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BACKGROUND OF THE INVENTION [0001] The invention relates to generation of responses to inbound EDI documents. [0002] A good deal of automation has been introduced for business-to-business electronic commerce systems using communication mechanisms such as EDI. However, in light of the fact that many users of such systems are required to perform a larger volume of transactions in any one working period, there is a requirement to introduce a greater deal of automation and reduce human interfacing time for performing transactions. [0003] The invention addresses this need. SUMMARY OF THE INVENTION [0004] According to the invention, there is provided a method of processing an inbound transaction document sent by a trading partner to a user in an electronic commerce system, the method comprising the steps of: [0005] receiving the inbound document at an interface for communication with trading partners; [0006] routing the inbound document to a mailbox of the user; [0007] automatically determining a set of candidate reply transaction documents associated with the inbound document; [0008] displaying a link to each candidate reply transaction document of said set adjacent to a header of the inbound document in a screen of a mailbox application for the user; [0009] receiving a user selection of a reply transaction document from said candidate set; [0010] parsing the inbound document to determine transaction data relevant to the selected reply document; [0011] automatically populating the selected reply document with said transaction data; [0012] generating a user edit screen displaying the automatically-populated selected transaction reply document, receiving a user input of additional transaction data, and writing said additional data to the reply document; and [0013] transmitting the reply document. [0014] In one embodiment, the system determines the set of candidate reply transaction documents by performing a look-up to a database indexed with the inbound document sender and addressee and the inbound document type. [0015] In another embodiment, the system determines the set of candidate reply transaction documents by operation of a translation engine: [0016] checking the inbound documents for compliance with a standard model, [0017] sending a negative functional acknowledgement to the trading partner or rejecting the inbound document if the compliance check is negative. [0018] In a one embodiment, the inbound document is parsed by a translation engine of the system translating the inbound document into a pre-populated selected reply document. [0019] In another embodiment, the translation engine writes the pre-populated selected reply document to a set of data structures in memory, and a mail engine of the system creates a pre-populated HTML reply document for rendering within a browser. [0020] In one embodiment, the additional data is inputted to the system with use of a tool for appending data to fields. [0021] In another embodiment, the additional data is inputted to the system with use of a tool for replacing automatically populated data. [0022] According to another aspect, the invention provides an electronic commerce system comprising means for performing a method as set out above. BRIEF DESCRIPTION OF THE DRAWINGS [0023] The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings in which: [0024] FIGS. 1 ( a ) and 1 ( b ) are together a flow diagram illustrating initialisation and real time document processing operations; [0025] [0025]FIG. 2 is a screen shot for an EDI document mailbox; and [0026] [0026]FIG. 3 is a screen shot illustrating a document generated by the system, in response to user interaction at the mailbox. DETAILED DESCRIPTION OF THE INVENTION [0027] Referring to FIGS. 1 ( a ) and 1 ( b ) an initialisation process 1 and a real time document processing process 20 are described. These processes are carried out by an EDI business-to-business automation system to reduce the extent of paperwork for conducting business, allow for transactions to be processed more speedily, and to make communication between trading partners more effective. [0028] In a step 2 of the initialisation process 1 , the system sets up a user profile in a database 3 . This includes: [0029] User logon ID [0030] Password [0031] EDI Address [0032] Company Information [0033] Company Name [0034] Address [0035] City/Town [0036] State/Province [0037] Postal Code [0038] Country [0039] Contact Information [0040] Contact First / Last Name [0041] Contact Address Information (same items as for Company Information) [0042] Phone Number / Phone Extension [0043] Fax Number [0044] E-mail Address [0045] Billing Information [0046] Billing Address Information (same items as for Company Information) [0047] Billing Subscription Type (i.e. Subscription Option (e.g. Monthly, Annually, Pay As You Go)). [0048] A setting (on/off) for automatic e-mail notification of documents received into mailbox. (By default, users are e-mailed when documents arrive in their mailbox. They have the ability to turn this feature off). [0049] Customised features such as custom folders and options for back-office integration. [0050] A trading partner (T/P) profile is set up in step 4 in a database 5 . This includes: [0051] EDI Address of the Trading Partner (TP) [0052] Company Information (as listed above) [0053] Contact Information (as listed above) [0054] EDI Transaction set information indicating the mandatory transaction sets that are to be traded between the partners. [0055] Trading relationship information that defines the limits of electronic trading between the partners (for example, “I can only send an Invoice to a trading partner, but I can not send a Purchase Order to the trading partner”). [0056] In step 6 , the system sets up inbound transaction documents, by either selecting from a database 7 of standard documents or by manually inputting text for new documents. Customised documents are saved to a database 8 . [0057] Outbound documents (from the user's perspective) are set up in page 9 . Again standard documents may be chosen or new ones created. [0058] In step 10 , the user then inputs to the system association of an outbound document for reply to each inbound document. These associations are indexed on the user profile ID and the trading partner profile ID. User profile and relationship data is audited and backed up. [0059] The real time process 20 is initiated with a step 21 in which an inbound document is received from one of the trading partners for which there is a profile stored in the database 5 . The sender and receiver addresses we identified in step 22 and are used in step 23 to perform a reply document look-up in the databases 5 and 8 . This look-up retrieves a list of the outbound reply transaction documents associated with the received inbound document. These documents are written to memory in step 24 . [0060] In more detail, the inbound document's interchange envelope is parsed to determine the type of EDI standard (protocol) that is used (e.g. ANSI, EDIFACT, or TRADACOMS). After this determination, the system sends an appropriate “standard model” and the inbound document to a compliance check function of a translation engine. A standard model is used to denote how a standard is syntactically formatted/delimited, and contains the accepted code lists for elements within the transaction set. [0061] The system uses the engine to compliance check the inbound document. If not compliant, the system will either send a negative functional acknowledgement back to the sending trading partner or completely reject the interchange. Which of these are done is specific to the EDI standard (protocol). [0062] If the system is configured for automatic real time notification of the user the remaining steps are initiated automatically. However, the system may be configured for generation of a reply only when the user requests viewing of an “inbox”, as in the illustrated embodiment in step 31 . [0063] Referring also to FIGS. 2 and 3, in this embodiment the system in step 32 displays a set of six inbound document headers. All of the documents relate to orders, and there is a unique identifier for each document. The sender is also indicated, as is the date. However, in addition, the system also displays automatically the candidate transaction reply documents determined in steps 23 and 24 to be available and appropriate for replies to the inbound documents. A HTML option is displayed for every possible transaction in the transaction set, for every displayed inbound document. In this example, the options have a header “Reply With” and the set comprises: [0064] “Orders Acknowledgement”, and [0065] “Invoice”. [0066] Thus, to generate a reply to an inbound document, the user only needs to click on the selected reply document in step 33 . The system then invokes the translation engine, giving it the inbound document and a translation model. The translation model is used to instruct the translation engine how to translate the inbound document into the target reply document. These instructions explain what data is pertinent from the inbound document, together with any computational or conditional operations. The translation (indicated in step 34 ) involves parsing the inbound document. After the translation, the system loads the newly-created outbound document from disk into a set of data structures in memory. [0067] A browser of the system then reads the data from the data structures and dynamically creates the pre-populated HTML document in step 35 , and it is rendered within the user's browser in step 36 . The end user may then change the contents of the document if necessary, and finally, send it to their trading partner. [0068] An example reply document is shown in FIG. 3. This is pre-populated with data drawn from the source document, determined in the parsing step 34 . The prepopulated data is in this example: [0069] Invoice type, [0070] user location, [0071] trading partner name and address, and [0072] user VAT Registration No. [0073] In step 37 the data is amended/augmented with use of tools having “Append” and “Remove” icons. These functions allow for the addition / removal of data to/from the transaction reply. These functions are particularly useful when human intervention is necessary to make changes within a document based on consequences at that point in time (for example “I will bill the trading partner for all items except item X”. Examples of data that can be added or removed are: [0074] Individual Line Items within a purchase order. [0075] Data narratives (descriptions about aspects of line items or other data within the transaction set). [0076] In the case of TRADACOMS EDI standards, addition or removal of an order within a set of orders. [0077] The finalised reply document is transmitted in step 38 . [0078] It will be appreciated that the invention provides for a very large extent of automation, thus minimising human error and allowing transactions to be more quickly processed. [0079] The invention thus provides the advantage of the user being presented with the appropriate available transaction set without the need to enter menus and manually “drill down” through a hierarchy. Only a single mouse or keyboard user input to select the transaction is required. Also, the document data is correct because it is selected by the system and so is not prone to human error. [0080] The invention is not limited to the embodiments described but may alternatively be varied in construction and detail. The reply document may be automatically populated together with all documents of the candidate set before user selection.
A business-to-business electronic commerce system receives inbound documents. As part of the step of sending to an addressee's mailbox, the system automatically determines candidate reply transaction documents appropriate and available to each inbound document. A HTML link is displayed for each available reply next to inbound document header data. Upon clicking of a selected reply from the candidate set the system automatically populates the selected reply document and prompts a user to complete.
Identify and summarize the most critical technical features from the given patent document.
[ "BACKGROUND OF THE INVENTION [0001] The invention relates to generation of responses to inbound EDI documents.", "[0002] A good deal of automation has been introduced for business-to-business electronic commerce systems using communication mechanisms such as EDI.", "However, in light of the fact that many users of such systems are required to perform a larger volume of transactions in any one working period, there is a requirement to introduce a greater deal of automation and reduce human interfacing time for performing transactions.", "[0003] The invention addresses this need.", "SUMMARY OF THE INVENTION [0004] According to the invention, there is provided a method of processing an inbound transaction document sent by a trading partner to a user in an electronic commerce system, the method comprising the steps of: [0005] receiving the inbound document at an interface for communication with trading partners;", "[0006] routing the inbound document to a mailbox of the user;", "[0007] automatically determining a set of candidate reply transaction documents associated with the inbound document;", "[0008] displaying a link to each candidate reply transaction document of said set adjacent to a header of the inbound document in a screen of a mailbox application for the user;", "[0009] receiving a user selection of a reply transaction document from said candidate set;", "[0010] parsing the inbound document to determine transaction data relevant to the selected reply document;", "[0011] automatically populating the selected reply document with said transaction data;", "[0012] generating a user edit screen displaying the automatically-populated selected transaction reply document, receiving a user input of additional transaction data, and writing said additional data to the reply document;", "and [0013] transmitting the reply document.", "[0014] In one embodiment, the system determines the set of candidate reply transaction documents by performing a look-up to a database indexed with the inbound document sender and addressee and the inbound document type.", "[0015] In another embodiment, the system determines the set of candidate reply transaction documents by operation of a translation engine: [0016] checking the inbound documents for compliance with a standard model, [0017] sending a negative functional acknowledgement to the trading partner or rejecting the inbound document if the compliance check is negative.", "[0018] In a one embodiment, the inbound document is parsed by a translation engine of the system translating the inbound document into a pre-populated selected reply document.", "[0019] In another embodiment, the translation engine writes the pre-populated selected reply document to a set of data structures in memory, and a mail engine of the system creates a pre-populated HTML reply document for rendering within a browser.", "[0020] In one embodiment, the additional data is inputted to the system with use of a tool for appending data to fields.", "[0021] In another embodiment, the additional data is inputted to the system with use of a tool for replacing automatically populated data.", "[0022] According to another aspect, the invention provides an electronic commerce system comprising means for performing a method as set out above.", "BRIEF DESCRIPTION OF THE DRAWINGS [0023] The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings in which: [0024] FIGS. 1 ( a ) and 1 ( b ) are together a flow diagram illustrating initialisation and real time document processing operations;", "[0025] [0025 ]FIG. 2 is a screen shot for an EDI document mailbox;", "and [0026] [0026 ]FIG. 3 is a screen shot illustrating a document generated by the system, in response to user interaction at the mailbox.", "DETAILED DESCRIPTION OF THE INVENTION [0027] Referring to FIGS. 1 ( a ) and 1 ( b ) an initialisation process 1 and a real time document processing process 20 are described.", "These processes are carried out by an EDI business-to-business automation system to reduce the extent of paperwork for conducting business, allow for transactions to be processed more speedily, and to make communication between trading partners more effective.", "[0028] In a step 2 of the initialisation process 1 , the system sets up a user profile in a database 3 .", "This includes: [0029] User logon ID [0030] Password [0031] EDI Address [0032] Company Information [0033] Company Name [0034] Address [0035] City/Town [0036] State/Province [0037] Postal Code [0038] Country [0039] Contact Information [0040] Contact First / Last Name [0041] Contact Address Information (same items as for Company Information) [0042] Phone Number / Phone Extension [0043] Fax Number [0044] E-mail Address [0045] Billing Information [0046] Billing Address Information (same items as for Company Information) [0047] Billing Subscription Type (i.e. Subscription Option (e.g. Monthly, Annually, Pay As You Go)).", "[0048] A setting (on/off) for automatic e-mail notification of documents received into mailbox.", "(By default, users are e-mailed when documents arrive in their mailbox.", "They have the ability to turn this feature off).", "[0049] Customised features such as custom folders and options for back-office integration.", "[0050] A trading partner (T/P) profile is set up in step 4 in a database 5 .", "This includes: [0051] EDI Address of the Trading Partner (TP) [0052] Company Information (as listed above) [0053] Contact Information (as listed above) [0054] EDI Transaction set information indicating the mandatory transaction sets that are to be traded between the partners.", "[0055] Trading relationship information that defines the limits of electronic trading between the partners (for example, “I can only send an Invoice to a trading partner, but I can not send a Purchase Order to the trading partner”).", "[0056] In step 6 , the system sets up inbound transaction documents, by either selecting from a database 7 of standard documents or by manually inputting text for new documents.", "Customised documents are saved to a database 8 .", "[0057] Outbound documents (from the user's perspective) are set up in page 9 .", "Again standard documents may be chosen or new ones created.", "[0058] In step 10 , the user then inputs to the system association of an outbound document for reply to each inbound document.", "These associations are indexed on the user profile ID and the trading partner profile ID.", "User profile and relationship data is audited and backed up.", "[0059] The real time process 20 is initiated with a step 21 in which an inbound document is received from one of the trading partners for which there is a profile stored in the database 5 .", "The sender and receiver addresses we identified in step 22 and are used in step 23 to perform a reply document look-up in the databases 5 and 8 .", "This look-up retrieves a list of the outbound reply transaction documents associated with the received inbound document.", "These documents are written to memory in step 24 .", "[0060] In more detail, the inbound document's interchange envelope is parsed to determine the type of EDI standard (protocol) that is used (e.g. ANSI, EDIFACT, or TRADACOMS).", "After this determination, the system sends an appropriate “standard model”", "and the inbound document to a compliance check function of a translation engine.", "A standard model is used to denote how a standard is syntactically formatted/delimited, and contains the accepted code lists for elements within the transaction set.", "[0061] The system uses the engine to compliance check the inbound document.", "If not compliant, the system will either send a negative functional acknowledgement back to the sending trading partner or completely reject the interchange.", "Which of these are done is specific to the EDI standard (protocol).", "[0062] If the system is configured for automatic real time notification of the user the remaining steps are initiated automatically.", "However, the system may be configured for generation of a reply only when the user requests viewing of an “inbox”, as in the illustrated embodiment in step 31 .", "[0063] Referring also to FIGS. 2 and 3, in this embodiment the system in step 32 displays a set of six inbound document headers.", "All of the documents relate to orders, and there is a unique identifier for each document.", "The sender is also indicated, as is the date.", "However, in addition, the system also displays automatically the candidate transaction reply documents determined in steps 23 and 24 to be available and appropriate for replies to the inbound documents.", "A HTML option is displayed for every possible transaction in the transaction set, for every displayed inbound document.", "In this example, the options have a header “Reply With”", "and the set comprises: [0064] “Orders Acknowledgement”, and [0065] “Invoice.”", "[0066] Thus, to generate a reply to an inbound document, the user only needs to click on the selected reply document in step 33 .", "The system then invokes the translation engine, giving it the inbound document and a translation model.", "The translation model is used to instruct the translation engine how to translate the inbound document into the target reply document.", "These instructions explain what data is pertinent from the inbound document, together with any computational or conditional operations.", "The translation (indicated in step 34 ) involves parsing the inbound document.", "After the translation, the system loads the newly-created outbound document from disk into a set of data structures in memory.", "[0067] A browser of the system then reads the data from the data structures and dynamically creates the pre-populated HTML document in step 35 , and it is rendered within the user's browser in step 36 .", "The end user may then change the contents of the document if necessary, and finally, send it to their trading partner.", "[0068] An example reply document is shown in FIG. 3. This is pre-populated with data drawn from the source document, determined in the parsing step 34 .", "The prepopulated data is in this example: [0069] Invoice type, [0070] user location, [0071] trading partner name and address, and [0072] user VAT Registration No. [0073] In step 37 the data is amended/augmented with use of tools having “Append”", "and “Remove”", "icons.", "These functions allow for the addition / removal of data to/from the transaction reply.", "These functions are particularly useful when human intervention is necessary to make changes within a document based on consequences at that point in time (for example “I will bill the trading partner for all items except item X.”", "Examples of data that can be added or removed are: [0074] Individual Line Items within a purchase order.", "[0075] Data narratives (descriptions about aspects of line items or other data within the transaction set).", "[0076] In the case of TRADACOMS EDI standards, addition or removal of an order within a set of orders.", "[0077] The finalised reply document is transmitted in step 38 .", "[0078] It will be appreciated that the invention provides for a very large extent of automation, thus minimising human error and allowing transactions to be more quickly processed.", "[0079] The invention thus provides the advantage of the user being presented with the appropriate available transaction set without the need to enter menus and manually “drill down”", "through a hierarchy.", "Only a single mouse or keyboard user input to select the transaction is required.", "Also, the document data is correct because it is selected by the system and so is not prone to human error.", "[0080] The invention is not limited to the embodiments described but may alternatively be varied in construction and detail.", "The reply document may be automatically populated together with all documents of the candidate set before user selection." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of co-pending U.S. patent application Ser. No. 13/555,755, filed on Jul. 23, 2012, which is a continuation of U.S. patent application Ser. No. 12/554,043, filed on Sep. 4, 2009, which claims priority to U.S. Provisional Application No. 61/227,923, filed on Jul. 23, 2009, the disclosures of which are hereby incorporated by reference herein in their entireties. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable REFERENCE TO A SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX Not Applicable BACKGROUND OF THE INVENTION 1. Technical Field of the Invention The present invention provides a method and apparatus for implementing a non-blocking minimal spanning switch. 2. Background of the Invention Telecommunication systems require switching networks to transmit data signals, or messages, from one point of the network to another point of the network. Many systems often employ the Clos Network, a type of switch network, for data transfer. The Clos Network is a multi-stage switch network, where each stage consists of a crossbar or crossbar switch. The system can be arranged into three stages: the ingress stage; the middle stage; and the egress stage. A total of n inputs are allowed into the ingress stage, where n=the total number of data input signals which are transmitted into the total crossbar connections (r) of the ingress stage for any other stage). The data input into the ingress stage is subsequently output from the ingress stage; a total of m outputs are allowed, where m=the total number of data output signals which are transmitted out of the ingress stage and m=the total number of crossbar connections located in the middle stage. One connection is provided to allow the data from the (n−1) data inputs of the ingress stage to be transmitted out of the ingress stage and into the middle stage, and one connection is provided to allow this data to be transmitted out of the middle stage and into the egress stage. The classic Clos Network switch fabric is illustrated in FIG. 7 . Charles Clos further defines a Strict-Sense Non-Blocking Clos Network, where unused ingress crossbar connections are connected to unused egress crossbar connections, where m≧(2n−1). In a typical three stage Clos Network, to guarantee the connection of n connections, (2n−1) crossbar connections are required in the middle stage; with (n−1) data inputs active in the ingress stage crossbar connections, and another (n−1) data inputs potentially active in the egress stage crossbar connections, (2n−2) crossbar connections are required in the middle stage to allow the connection, where (n−1)+(n−1)=(2n−2). However, as (2n−2) crossbar connections may be unable to provide every necessary connection, an extra crossbar is provided to ensure Strict-Sense Non-Blocking, with (2n−1) middle stage crossbar connections. (2n−1) middle stage crossbar connections would consume a large amount of resources, but in a Clos Network, m≧(2n−1) is necessary to maintain Strict-Sense Non-. Blocking. When implementing a Clos Network which does not adhere to m≧(2n−1), the data connections may need to be re-routed in order to establish new connections, and such re-routing would result in interrupted or blocked connections, i.e., dropped telephone connections. One method of minimizing the number of crossbar connections in the middle stage is through the use of a Non-Blocking Minimal Spanning Switch, When using a Non-Blocking Minimal Spanning Switch system, the connections between the ingress stage, middle stage and egress stage are symmetrical, with n ingress stage crossbar connections, n middle stage crossbar connections and n egress stage crossbar connections, This is achieved through the use of multiple sub-switches located in each stage; as an example a 4×4 switch including two input crossbar connections and two output crossbar connections are used. In a Non-Blocking Minimal Spanning Switch system, any data input signal input to any ingress location may be output from any egress location provided there is an open connection and an open path; however, signals can be blocked when they arrive from the ingress stage to the middle stage where the sub-switch locations are already in use, requiring other signals to be re-routed to ensure transmission, Such re-routing of signals is undesirable; the signals being transmitted are already carrying data, thus re-routing the data signal would again result in interrupted or blocked connections, i.e., dropped telephone connections. Therefore, a method of re-routing the data signals transmitted through switching fabrics, without causing such interruptions, is required. SUMMARY OF THE INVENTION The present invention discloses a novel Strict-Sense Minimal Spanning Non-Blocking Architecture for use in frame-based data communications networks, providing the ability to re-route a telecommunications connection without interrupting the data signal. To maximize efficiency, the amount of logic duplicated on each data stream is minimized through the use of a n framer system, where n=the total number of framers in the system. In addition, n=the total number of data input signals which are transmitted into the crossbar connections (r) of the system. In the present invention, a “framer”refers to a machine which recognizes inherent framing patterns in transmitted data which occurs at predictable intervals. In the n framer system, each of the n bit streams enters n framers at a crossbar connection, and the n framers subsequently determine the inherent framing patterns within the transmitted data which are necessary for re-alignment. From these inherent framing patterns, the n framers can derive an arbitrary frame start signal, or the “start of frame.” The start of frame, as derived by the n framers, indicates to the n framers to write the transmitted data into a specific, but arbitrary location(s) of buffers. These arbitrary locations of n butfery ocprcunnt the offsetting bit location in each of the n buffers where the n framers are to start writing the transmitted data to allow the data to be written into the n buffers in a re-aligned fashion. A multiplexer can then read out the realigned data from the n buffers and select from any of the re-aligned data signals to provide a single data output signal. In an illustrative embodiment of the invention, the n incoming data input signals are transmitted to n framers, where each of the n incoming data input signals are divided into d data signals, where d can be any arbitrary and user-definable amount of data signals. This provides a total of x internal data signals, as n×d=x. The x internal data signals are then written into a specific, but arbitrary location(s) of x buffers. A multiplexer can then read out the realigned data from the x uffers and select one, single data output signal; i.e., each crossbar connection has one data output signal, therefore m crossbar connections have m data output signals. Through this method, each crossbar connection of the switch will output the exact same data in each of the m data output signals. Therefore, when any of m crossbar connections (where m=the total number of data output signals switches from one sub-switch to another sub-switch, no interruption occurs; as the data on each sub-switch within a crossbar connection is identical, any connection can be successfully used by the switch. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram illustrating four inputs and one output of a switch (prior art). FIG. 2 is a block diagram illustrating the basic structure of a 4×4 switch (prior art). FIG. 3 is a block diagram illustrating four data signals input into a 4×4 switch (prior art). FIG. 4 is a block diagram illustrating four data inputs and one data output in accordance with an illustrative embodiment of the present invention. FIG. 5 is a block diagram illustrating the internal circuitry of each sub-switch in accordance with an illustrative embodiment of the present invention. FIG. 6 is a block diagram illustrating four data signals input to four crossbar connections and four data signals output from the four crossbar connections in accordance with an illustrative embodiment of the present invention. FIG. 7 is a block diagram illustrating a simplified version of the classic Cloy Network switch fabric (prior art). DETAILED DESCRIPTION OF THE INVENTION An illustrative embodiment of the invention employs a n framer system as applied to a 4×4 switch, The crossbar connections employed triay be Field Programmable Gate Arrays (FPGAs) or any other logic circuitry element. It should be noted that this example is provided for illustrative purposes only and is not meant to limit the scope of the invention, as any size switch can be accommodated. In the 4×4 switch, each of the crossbar connections m has four separate data input locations and one single data output location, This is illustrated in FIG, 1 , where four data input signals A, B, C and D enter a single crossbar connection m( 1 ), where multiplexer ( 1 ) selects one of data input signals A, B, C and D and subsequently outputs the signal from the system through the single data output location; this is illustrated as data output signal W. As illustrated in FIG. 2 , the 4×4 switch is composed of four crossbar connections, m( 1 ), m( 2 ), m( 3 ) and m( 4 ). The input of the four data input signals A, B, C and D into the 4×4 switch is illustrated in FIG. 3 , where each of the four data input signals A, B, C and D are input into each of the four crossbar connections, m( 1 ), m( 2 ), m( 3 ) and m( 4 ); the four data input signals A, B, C and D transmitted into each of the four crossbar connections, m( 1 ), m( 2 ), m( 3 ) and m( 4 ) provides a total of 16 data inputs to the 4×4 switch. However, each of multiplexers 1 ( 1 ), 1 ( 2 ), 1 ( 3 ) and 1 ( 4 ), located in crossbar connections, m( 1 ), m( 2 ), m( 3 ) and m( 4 ), respectively, select from the four data inputs to provide one data output for each of crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ), for a total of four data output signals, W, X, Y and Z. As illustrated in FIG. 3 , data output signal W is output from m( 1 ), data output signal X is output from m( 2 ), data output signal Y is output from m( 3 ), and data output signal Z is output from m( 4 ). FIG. 4 provides an illustrative embodiment of the Strict-Sense Minimal Spanning Non-Blocking Architecture applied to a 4×4 switch system. As illustrated, each of data input signals A, B, C and D are fed into their respective data input locations of crossbar connection m( 1 ). Please note that each of data input signals A, B, C and D are likewise fed into respective data input locations of crossbar connections m( 2 ), ( 3 ) and m( 4 ), as the internal circuitry of the crossbar connection m( 1 ) is identical to the internal circuitry of m( 2 ), m( 3 ) a d m( 4 ); thus FIG. 4 can be considered as representation of any of crossbar connections m. As illustrated in FIG. 4 , the data input to each of data input locations A, B, C and D enters one of framers ( 2 ). The framers ( 2 ) are able to recognize the start of frame, or the first byte of the frame. Framers ( 2 ) detect the start of frame in the incoming data by identifying the Frame Alignment Signal (FAS), an inherent and repeating framing pattern. With the start of frame known, the four data input signals A, B, C and D can be written into buffers ( 3 ) in a re-aligned fashion, writing the start of frame, or any other common starting byte, into a first common and specific location of each of buffers ( 3 ), despite any difference in the arrival times for each of data input signals A, B, C and D. Multiplexer 1 ( 1 ) can now read data out of a second common and specific location of each of buffers ( 3 ). Please note that these common first and second locations in each of buffers ( 3 ) can be any arbitrary and user-definable data locations. A pointer from multiplexer 1 ( 1 ) reads the re-aligned data out of the second common and specific location of each of buffers ( 3 ), ensuring that re-aligned and skew-free data is read from the buffers, despite any difference in arrival times between data input signals A, B, C and D. Multiplexer 1 ( 1 ) now selects from the data input signals A, B, C and D to provide a single data output, W. The full 4×4 switch is illustrated in FIG. 6 , where the four data input signals A, B, C and D, are input into each of the four crossbar connections m( 1 ), m( 2 ), ( 3 ) and m( 4 ). Once the data is selected from the four input signals of each of the four crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ) via the internal circuitry illustrated in FIG. 4 , one data signal is output from each of the four crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ), for a total of four data signals output from the system. This is illustrated in FIG. 6 , where the four data output signals, W, X, Y and Z, are input into each of the four crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ). Each of the data output signals, W, X, Y and Z will carry identical data, thus any of crossbar connections m( 1 ), m( 2 ), m( 3 ) or ( 4 ) may be chosen to make a connection. DETAILED DESCRIPTION OF AN ILLUSTRATIVE EMBODIMENT OF THE INVENTION FIG. 5 illustrates a further illustrative embodiment of the present invention, employing a trunk framing system, where a trunk lane allows for one or more logical lanes in a single trunk lane. This illustrative embodiment of the invention is provided for illustrative purposes only and is not meant to limit the scope of the invention, as the invention may be applied to time switches or combinational space-time switches. The invention again employs a n framer system as applied to a 4×4 switch. The crossbar connections employed may be Field Programmable Gate Arrays (FPGAs) or any other logic circuitry element. It should be noted that this example is provided for illustrative purposes only and is not meant to limit the scope of the invention, as any size switch can be accommodated. As illustrated in FIG. 5 , trunk framers ( 7 ) receive the data input signals A, B, C and D, identify the start of frame, and therefore identify the frame alignment for each of data input signals A, B, C and D. With the framing pattern identified, de-multiplexers ( 8 ) divide each of trunk lanes A, B, C and D into four logical lanes ( 9 ), for a total of 16 logical lanes ( 9 ) in the system. Therefore, in a 4×4 switch, 64 logical lanes would exist within the 4 crossbar connections, As illustrated, with the start of frame known, each of the 16 logical lanes ( 9 ) within a single crossbar connection can be written into one of buffers ( 5 ) in a re-aligned fashion, with the start of frame, or any other common starting byte, written into a first common and specific location of each of buffers ( 5 ), despite any difference in the arrival times for each of the 16 logical lanes ( 9 ). The data from each of the logical lanes ( 9 ) remains buffered in buffers ( 5 ) until multiplexer ( 6 ) sends a pointer to each of the 16 buffers ( 5 ) to read data out of a second common and specific location of each of buffers ( 5 ). Again, this ensures that multiplexer ( 6 ) reads out re-aligned and skew-free data from each of buffers ( 6 ), despite any difference in arrival times between data input signals A, B, C and D, or any timing differences between logical lanes ( 9 ). Multiplexer ( 6 ) now selects from the 16 logical lanes ( 9 ) to provide a single data output, W. Through using this Strict-Sense Minimal Spanning Non-Blocking Architecture, the present invention ensures that each of the four crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ) output the exact same data in each of the four data output signals, W, X, Y and Z, respectively. Therefore, when the 4×4 switch switches from one of crossbar connections m( 1 ), m( 2 ), m( 3 ) or m( 4 ), to any other of crossbar connections m( 1 ), m( 2 ), m( 3 ) or m( 4 ), no interruption occurs; the data on each crossbar connection m( 1 ), ( 2 ), m( 3 ) and m( 4 ) is identical, thus any connection can be used for the switch. This allows for the use of a m=n Non-Blocking Minimal Spanning Switch, where n=the total number of data input signals and m=the total number of data output signals and m=the number of crossbar connections in each switch, while eliminating the possibility of data interrupts.
The present invention discloses an apparatus to implement a m=n Non-Blocking Minimal Spanning Switch, where n=the total number of data input signals and m=the total number of data output signals and m=the number of crossbar connections in each switch. Data is input to the switch as a plurality of frames, whereby each crossbar connection contains a framer which detects framing patterns in the data. Skewed data is re-aligned and buffered so that the data output by each crossbar connection is equal and identical, thus any crossbar connection may be used to ensure a connection, eliminating the possibility of data interrupts.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of co-pending U.S. patent application Ser.", "No. 13/555,755, filed on Jul. 23, 2012, which is a continuation of U.S. patent application Ser.", "No. 12/554,043, filed on Sep. 4, 2009, which claims priority to U.S. Provisional Application No. 61/227,923, filed on Jul. 23, 2009, the disclosures of which are hereby incorporated by reference herein in their entireties.", "STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable REFERENCE TO A SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX Not Applicable BACKGROUND OF THE INVENTION 1.", "Technical Field of the Invention The present invention provides a method and apparatus for implementing a non-blocking minimal spanning switch.", "Background of the Invention Telecommunication systems require switching networks to transmit data signals, or messages, from one point of the network to another point of the network.", "Many systems often employ the Clos Network, a type of switch network, for data transfer.", "The Clos Network is a multi-stage switch network, where each stage consists of a crossbar or crossbar switch.", "The system can be arranged into three stages: the ingress stage;", "the middle stage;", "and the egress stage.", "A total of n inputs are allowed into the ingress stage, where n=the total number of data input signals which are transmitted into the total crossbar connections (r) of the ingress stage for any other stage).", "The data input into the ingress stage is subsequently output from the ingress stage;", "a total of m outputs are allowed, where m=the total number of data output signals which are transmitted out of the ingress stage and m=the total number of crossbar connections located in the middle stage.", "One connection is provided to allow the data from the (n−1) data inputs of the ingress stage to be transmitted out of the ingress stage and into the middle stage, and one connection is provided to allow this data to be transmitted out of the middle stage and into the egress stage.", "The classic Clos Network switch fabric is illustrated in FIG. 7 .", "Charles Clos further defines a Strict-Sense Non-Blocking Clos Network, where unused ingress crossbar connections are connected to unused egress crossbar connections, where m≧(2n−1).", "In a typical three stage Clos Network, to guarantee the connection of n connections, (2n−1) crossbar connections are required in the middle stage;", "with (n−1) data inputs active in the ingress stage crossbar connections, and another (n−1) data inputs potentially active in the egress stage crossbar connections, (2n−2) crossbar connections are required in the middle stage to allow the connection, where (n−1)+(n−1)=(2n−2).", "However, as (2n−2) crossbar connections may be unable to provide every necessary connection, an extra crossbar is provided to ensure Strict-Sense Non-Blocking, with (2n−1) middle stage crossbar connections.", "(2n−1) middle stage crossbar connections would consume a large amount of resources, but in a Clos Network, m≧(2n−1) is necessary to maintain Strict-Sense Non-.", "Blocking.", "When implementing a Clos Network which does not adhere to m≧(2n−1), the data connections may need to be re-routed in order to establish new connections, and such re-routing would result in interrupted or blocked connections, i.e., dropped telephone connections.", "One method of minimizing the number of crossbar connections in the middle stage is through the use of a Non-Blocking Minimal Spanning Switch, When using a Non-Blocking Minimal Spanning Switch system, the connections between the ingress stage, middle stage and egress stage are symmetrical, with n ingress stage crossbar connections, n middle stage crossbar connections and n egress stage crossbar connections, This is achieved through the use of multiple sub-switches located in each stage;", "as an example a 4×4 switch including two input crossbar connections and two output crossbar connections are used.", "In a Non-Blocking Minimal Spanning Switch system, any data input signal input to any ingress location may be output from any egress location provided there is an open connection and an open path;", "however, signals can be blocked when they arrive from the ingress stage to the middle stage where the sub-switch locations are already in use, requiring other signals to be re-routed to ensure transmission, Such re-routing of signals is undesirable;", "the signals being transmitted are already carrying data, thus re-routing the data signal would again result in interrupted or blocked connections, i.e., dropped telephone connections.", "Therefore, a method of re-routing the data signals transmitted through switching fabrics, without causing such interruptions, is required.", "SUMMARY OF THE INVENTION The present invention discloses a novel Strict-Sense Minimal Spanning Non-Blocking Architecture for use in frame-based data communications networks, providing the ability to re-route a telecommunications connection without interrupting the data signal.", "To maximize efficiency, the amount of logic duplicated on each data stream is minimized through the use of a n framer system, where n=the total number of framers in the system.", "In addition, n=the total number of data input signals which are transmitted into the crossbar connections (r) of the system.", "In the present invention, a “framer”refers to a machine which recognizes inherent framing patterns in transmitted data which occurs at predictable intervals.", "In the n framer system, each of the n bit streams enters n framers at a crossbar connection, and the n framers subsequently determine the inherent framing patterns within the transmitted data which are necessary for re-alignment.", "From these inherent framing patterns, the n framers can derive an arbitrary frame start signal, or the “start of frame.”", "The start of frame, as derived by the n framers, indicates to the n framers to write the transmitted data into a specific, but arbitrary location(s) of buffers.", "These arbitrary locations of n butfery ocprcunnt the offsetting bit location in each of the n buffers where the n framers are to start writing the transmitted data to allow the data to be written into the n buffers in a re-aligned fashion.", "A multiplexer can then read out the realigned data from the n buffers and select from any of the re-aligned data signals to provide a single data output signal.", "In an illustrative embodiment of the invention, the n incoming data input signals are transmitted to n framers, where each of the n incoming data input signals are divided into d data signals, where d can be any arbitrary and user-definable amount of data signals.", "This provides a total of x internal data signals, as n×d=x.", "The x internal data signals are then written into a specific, but arbitrary location(s) of x buffers.", "A multiplexer can then read out the realigned data from the x uffers and select one, single data output signal;", "i.e., each crossbar connection has one data output signal, therefore m crossbar connections have m data output signals.", "Through this method, each crossbar connection of the switch will output the exact same data in each of the m data output signals.", "Therefore, when any of m crossbar connections (where m=the total number of data output signals switches from one sub-switch to another sub-switch, no interruption occurs;", "as the data on each sub-switch within a crossbar connection is identical, any connection can be successfully used by the switch.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram illustrating four inputs and one output of a switch (prior art).", "FIG. 2 is a block diagram illustrating the basic structure of a 4×4 switch (prior art).", "FIG. 3 is a block diagram illustrating four data signals input into a 4×4 switch (prior art).", "FIG. 4 is a block diagram illustrating four data inputs and one data output in accordance with an illustrative embodiment of the present invention.", "FIG. 5 is a block diagram illustrating the internal circuitry of each sub-switch in accordance with an illustrative embodiment of the present invention.", "FIG. 6 is a block diagram illustrating four data signals input to four crossbar connections and four data signals output from the four crossbar connections in accordance with an illustrative embodiment of the present invention.", "FIG. 7 is a block diagram illustrating a simplified version of the classic Cloy Network switch fabric (prior art).", "DETAILED DESCRIPTION OF THE INVENTION An illustrative embodiment of the invention employs a n framer system as applied to a 4×4 switch, The crossbar connections employed triay be Field Programmable Gate Arrays (FPGAs) or any other logic circuitry element.", "It should be noted that this example is provided for illustrative purposes only and is not meant to limit the scope of the invention, as any size switch can be accommodated.", "In the 4×4 switch, each of the crossbar connections m has four separate data input locations and one single data output location, This is illustrated in FIG, 1 , where four data input signals A, B, C and D enter a single crossbar connection m( 1 ), where multiplexer ( 1 ) selects one of data input signals A, B, C and D and subsequently outputs the signal from the system through the single data output location;", "this is illustrated as data output signal W. As illustrated in FIG. 2 , the 4×4 switch is composed of four crossbar connections, m( 1 ), m( 2 ), m( 3 ) and m( 4 ).", "The input of the four data input signals A, B, C and D into the 4×4 switch is illustrated in FIG. 3 , where each of the four data input signals A, B, C and D are input into each of the four crossbar connections, m( 1 ), m( 2 ), m( 3 ) and m( 4 );", "the four data input signals A, B, C and D transmitted into each of the four crossbar connections, m( 1 ), m( 2 ), m( 3 ) and m( 4 ) provides a total of 16 data inputs to the 4×4 switch.", "However, each of multiplexers 1 ( 1 ), 1 ( 2 ), 1 ( 3 ) and 1 ( 4 ), located in crossbar connections, m( 1 ), m( 2 ), m( 3 ) and m( 4 ), respectively, select from the four data inputs to provide one data output for each of crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ), for a total of four data output signals, W, X, Y and Z. As illustrated in FIG. 3 , data output signal W is output from m( 1 ), data output signal X is output from m( 2 ), data output signal Y is output from m( 3 ), and data output signal Z is output from m( 4 ).", "FIG. 4 provides an illustrative embodiment of the Strict-Sense Minimal Spanning Non-Blocking Architecture applied to a 4×4 switch system.", "As illustrated, each of data input signals A, B, C and D are fed into their respective data input locations of crossbar connection m( 1 ).", "Please note that each of data input signals A, B, C and D are likewise fed into respective data input locations of crossbar connections m( 2 ), ( 3 ) and m( 4 ), as the internal circuitry of the crossbar connection m( 1 ) is identical to the internal circuitry of m( 2 ), m( 3 ) a d m( 4 );", "thus FIG. 4 can be considered as representation of any of crossbar connections m. As illustrated in FIG. 4 , the data input to each of data input locations A, B, C and D enters one of framers ( 2 ).", "The framers ( 2 ) are able to recognize the start of frame, or the first byte of the frame.", "Framers ( 2 ) detect the start of frame in the incoming data by identifying the Frame Alignment Signal (FAS), an inherent and repeating framing pattern.", "With the start of frame known, the four data input signals A, B, C and D can be written into buffers ( 3 ) in a re-aligned fashion, writing the start of frame, or any other common starting byte, into a first common and specific location of each of buffers ( 3 ), despite any difference in the arrival times for each of data input signals A, B, C and D. Multiplexer 1 ( 1 ) can now read data out of a second common and specific location of each of buffers ( 3 ).", "Please note that these common first and second locations in each of buffers ( 3 ) can be any arbitrary and user-definable data locations.", "A pointer from multiplexer 1 ( 1 ) reads the re-aligned data out of the second common and specific location of each of buffers ( 3 ), ensuring that re-aligned and skew-free data is read from the buffers, despite any difference in arrival times between data input signals A, B, C and D. Multiplexer 1 ( 1 ) now selects from the data input signals A, B, C and D to provide a single data output, W. The full 4×4 switch is illustrated in FIG. 6 , where the four data input signals A, B, C and D, are input into each of the four crossbar connections m( 1 ), m( 2 ), ( 3 ) and m( 4 ).", "Once the data is selected from the four input signals of each of the four crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ) via the internal circuitry illustrated in FIG. 4 , one data signal is output from each of the four crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ), for a total of four data signals output from the system.", "This is illustrated in FIG. 6 , where the four data output signals, W, X, Y and Z, are input into each of the four crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ).", "Each of the data output signals, W, X, Y and Z will carry identical data, thus any of crossbar connections m( 1 ), m( 2 ), m( 3 ) or ( 4 ) may be chosen to make a connection.", "DETAILED DESCRIPTION OF AN ILLUSTRATIVE EMBODIMENT OF THE INVENTION FIG. 5 illustrates a further illustrative embodiment of the present invention, employing a trunk framing system, where a trunk lane allows for one or more logical lanes in a single trunk lane.", "This illustrative embodiment of the invention is provided for illustrative purposes only and is not meant to limit the scope of the invention, as the invention may be applied to time switches or combinational space-time switches.", "The invention again employs a n framer system as applied to a 4×4 switch.", "The crossbar connections employed may be Field Programmable Gate Arrays (FPGAs) or any other logic circuitry element.", "It should be noted that this example is provided for illustrative purposes only and is not meant to limit the scope of the invention, as any size switch can be accommodated.", "As illustrated in FIG. 5 , trunk framers ( 7 ) receive the data input signals A, B, C and D, identify the start of frame, and therefore identify the frame alignment for each of data input signals A, B, C and D. With the framing pattern identified, de-multiplexers ( 8 ) divide each of trunk lanes A, B, C and D into four logical lanes ( 9 ), for a total of 16 logical lanes ( 9 ) in the system.", "Therefore, in a 4×4 switch, 64 logical lanes would exist within the 4 crossbar connections, As illustrated, with the start of frame known, each of the 16 logical lanes ( 9 ) within a single crossbar connection can be written into one of buffers ( 5 ) in a re-aligned fashion, with the start of frame, or any other common starting byte, written into a first common and specific location of each of buffers ( 5 ), despite any difference in the arrival times for each of the 16 logical lanes ( 9 ).", "The data from each of the logical lanes ( 9 ) remains buffered in buffers ( 5 ) until multiplexer ( 6 ) sends a pointer to each of the 16 buffers ( 5 ) to read data out of a second common and specific location of each of buffers ( 5 ).", "Again, this ensures that multiplexer ( 6 ) reads out re-aligned and skew-free data from each of buffers ( 6 ), despite any difference in arrival times between data input signals A, B, C and D, or any timing differences between logical lanes ( 9 ).", "Multiplexer ( 6 ) now selects from the 16 logical lanes ( 9 ) to provide a single data output, W. Through using this Strict-Sense Minimal Spanning Non-Blocking Architecture, the present invention ensures that each of the four crossbar connections m( 1 ), m( 2 ), m( 3 ) and m( 4 ) output the exact same data in each of the four data output signals, W, X, Y and Z, respectively.", "Therefore, when the 4×4 switch switches from one of crossbar connections m( 1 ), m( 2 ), m( 3 ) or m( 4 ), to any other of crossbar connections m( 1 ), m( 2 ), m( 3 ) or m( 4 ), no interruption occurs;", "the data on each crossbar connection m( 1 ), ( 2 ), m( 3 ) and m( 4 ) is identical, thus any connection can be used for the switch.", "This allows for the use of a m=n Non-Blocking Minimal Spanning Switch, where n=the total number of data input signals and m=the total number of data output signals and m=the number of crossbar connections in each switch, while eliminating the possibility of data interrupts." ]
REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. application Ser. No. 098,699 filed Sept. 18, 1987, now abandoned, entitled "Pilfer Proofing System For Electric Utility Meter Box" which is a continuation-in-part of U.S. application Ser. No. 694,368 filed Jan. 24, 1985, entitled "Pilfer Proofing System And Method For Electric Utility Meter Box", now U.S. Pat. No. 4,615,113 which is a division of U.S. application Ser. No. 526,236 filed Aug. 25, 1983, now U.S. Pat. No. 4,505,530 which, in turn, is a division of U.S. application Ser. No. 170,205 filed Aug. 18, 1980, now U.S. Pat. No. 4,404,521, all of which are incorporated herein by reference. BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION In the above-referenced patent application and U.S. Pat. No. 4,404,521, 4,505,530, and 4,615,113 there is disclosed a pilfer proofing system and method for electric utility meter boxes which adapts existing ringless-type meter boxes to locking ring-type meter boxes without disconnecting the box from the incoming power lines. An objective of the present invention is to provide an improved pilfer proofing system that does not require the serviceman to drill any holes and which is faster and easier to install than the system disclosed in the above patents while retaining the key feature of being able to install the pilfer proofing system and convert the ringless-type meter boxes to a locking ring-type meter box without disconnecting the box from the incoming power lines e.g., while the meter box is electrified. According to this invention, a plug-in meter contact terminal block set adaptor as disclosed and claimed in the above U.S. Pat. No. 4,505,530 is used to carry an embedded metal bar which is secured to a pair of short meter stop clamp bars so as to expeditiously properly position the clamp bars behind the meter stops. A feature of the present invention is that the clamp bars, in one preferred embodiment, have bifurcated ends which slide under "Tee"-type meter stops, and also are coated with an electrical grade epoxy or PVC insulation. The bifurcation of the ends of the clamp bars provides a four point contact system for clamping the cover to the meter box and thereby enhances the security of the system, while at the same time, enlarging the types and range of meter boxes which can be safely, easily and quickly pilfer proofed by the invention at very low cost. A cast aluminum ring having an end adapted to abut the meter stop in the same way that the conventional meter abuts the meter stops, passes through the meter opening in the meter box cover to engage the meter stops and a pair of inwardly projecting lugs, integrally molded with the ring, are provided with elongated slots or holes through which pass locking bolts which engage threaded bores in the locking clamps. While the aluminum ring may be coated with an insulating coating, it is also grounded to the metal box. In another embodiment, the ring is a molded plastic element. When the bolts passing through the elongated slots in the cast aluminum ring are tightened, the meter stops are securely clamped between the metal clamp bars and the inner-most end of the annular ring. In the case of the bifurcated clamp bar ends, the end bifurcation may project under the cover edge at the meter opening so the clamp action may include that portion of the cover bounding the meter opening. The ring is provided with an enlarged annular flange which completely seals the opening in the meter box cover to prevent any surreptitious access thereto and a locating tab and set screw facilitate positioning the ring in place in the cover. Then the meter is plugged into the terminal block adaptor set and the locking ring or sealing band is applied over the shoulder of the meter itself and a locking flange on the cast annular ring to thereby lock and seal the meter to the projecting meter collar and flange. The operation can be done fast (about 3 minutes) and inexpensively, and there are no screws or drilling required to perform the installation. As noted above, the bifurcated clamp bar ends provide a four point contact with the meter stops and/or the edge of the meter box. Moreover, no special tools are required for installation, which can be done on a "live" meter box (no time is spent disconnecting service to the pole). Accordingly, the basic objective of the invention is to provide an improved pilfer proofing apparatus and method following the teachings of the above-identified related applications, which can be installed by the serviceman fast and inexpensively with only a screwdriver. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, advantages and features of the invention will become more apparent when considered in conjunction with the following specification and accompanying drawings wherein: FIG. 1 is an exploded perspective view of a pilfer proof meter box incorporating the invention, FIG. 2 is a section line through a portion of the meter box showing the clamping or locking end of the adaptor components to the meter stops, FIG. 3 is a top plan view of the insulated carrier for the contact block socket adaptor assembly, FIG. 4 is a sectional view on lines 4--4 of FIG. 3, FIG. 5 is a plan view of the adaptor, FIG. 6 is a side view thereof, FIG. 7a is a top plan view of clamp bars, and FIG. 7b is a side elevational view thereof, FIG. 8 is a perspective view of the male-female elements carried by the contact set block adaptors, FIG. 9 is a top plan view of a bifurcated chamber which can be used for meter boxes having "Tee"-type meter stops, FIG. 10 is a sectional view on lines 10--10 of FIG. 9, FIG. 11 is a perspective view showing how the bifurcated clamp bar slides under the "Tee"-type meter stop, and FIG. 12 is an exploded view showing the installation with the bifurcated clamp bars. DETAILED DESCRIPTION OF THE INVENTION In the exploded perspective view of FIG. 1, an existing sheet metal meter box 10 has an input power cable 13 passing through gland 12 on the top 11 of box 10 with the electrical cables connected to the female contact jaws 16 and 17 of terminal block set 18 mounted on commercial base of box 10. Power to the user, which may be a home or commercial establishment, is supplied through conductors 19 which pass through a bottom gland 20 in the bottom 21 of box 10. With the meter 23 plugged-in with its upper male contacts 24 received in the female terminals 16 and 17 and the lower male terminals 25 plugged into the lower female terminals 26 [and 27] of the terminal block set 15, electrical power flows in through the conductor cable 13 through meter 23 and out through cable 19 to the user. The meter box cover 25 has an upper edge 25U sliding under a peripheral flange 26 on the top of box 10. Depending flanges or skirts 27 which fit over and closes off the edges of the two sidewalls and bottom wall of the meter box enclosure 10. Service to a customer may be terminated for various reasons. Various forms of insulated disconnect sleeves DS, as disclosed in U.S. Pat. No. 2,643,362 and 3,528,049, may be placed on the load sides of the male contact blades so that when the meter is plugged into the female sockets 16, 17 of the terminal block set 18, the customer will be prevented from receiving electrical power. In the usual case, prior to fitting the cover plate 25 onto the meter box 10, the meter unit 23 which has the rearwardly projecting contact blades 24,24 and 25,25 is plugged into the female contact jaws 16, 17 and 26, 27 in the terminal block set 18 as described above. A pair of meter stops 26 and 27 are secured to the sidewalls of meter box 10 by rivots or, preferably by welding. An annular shoulder 28 is formed at the base of glass cover 21 and a corresponding raised shoulder 25S is formed in the cover 25 so that when the cover 20 is fitted on the box 10, the glass meter cover 23 projects through the opening bounded by the flange 29 and annular shoulder 25S engages shoulder 28 to thereby retain the meter in place. A tongue 30 is secured to the bottom wall of meter box 10, and projects through a slot 31 in cover 25. A slide 32 secured to cover 25 has a projecting tongue 33 which has an aperture 34 which aligns with an aperture 35 in tongue 30. Slide 32 is positioned so that the two apertures 34 and 35 align and a safety seal (not shown) is used to provide an indication of tampering. As noted in the above related patents and related applications, in the past, those electric utility customers who have a proclivity to pilfer electricity have found it very easy to tamper with the safety seal (making it appear as if no tampering had taken place or easily disclaiming responsibility for the tampering) and easily gain access to the meter and tamper with same in various ways so as to bypass the meter and thereby inaccurately portray their actual electricity usage. In order to avoid this tampering, the invention utilizes essentially three components: I. a terminal block adaptor 40, II. a pair of clamp bars 50L and 50R having bifurcated ends, and III. an annular locking flange assembly 70. The contact terminal block adaptor 40 is similar in all major respects to the contact terminal block adaptor disclosed in the above-mentioned Fennell patents. The contact block adaptor 40 includes a molded insulating plastic carrier 40C (FIG. 3; FIG. 4) which has a central pocket portion 83 in which is received a steel bar 84 that has a pair of bored and tapped holes 85-1, 85-2 aligned with holes 86-1 and 86-2 in the base of the pocket 83. A pair of clamp brackets 50L and 50R (shown in detail in FIGS. 7a and 7b) are secured in position on the bottom of pocket 83 by screw fasteners 87-1, 87-2 which pass through elongated slots 88-1 and 88-2, holes 86-1 and 86-2 and in threaded engagement with bored and tapped holes 85-1 and 85-2 to thereby adjustably mount brackets 50L and 50R on the adaptor 40. Brackets 50L and 50R have a shape such that their outermost ends 50LO and 50RO fit behind meter stops 26 and 27, respectively with a short straight section carrying a threaded and tapped holes 50LT and 50RT, the purpose of which will be described more fully hereafter. Since one of the prime objectives of the invention is to be able to pilfer proof a box while it is still connected to the line without danger to the serviceman, the upper female contacts 82, 83 in the adaptor 40 are protected by a safety shield 90 (FIG. 8) which in conjunction with walls or barriers W insulates these "hot" (electrically) conductor elements during the pilfer proofing operation. Safety shield 90 (which is functionally similar to the safety shield shown in the above related patents) has a pair of non-conductive blade members 90B for frictionally retaining the shield in place in the hot conductor elements while the clamp brackets 50L and 50R are being installed in the manner described above. The plastic cover or cap 90 in this case can be similar in construction to the meter disconnect device disclosed in U.S. Pat. No. 3,614,708 and has a handle H thereon for safe and easy removal of cover 90 after the installation of the pilfer proofing adaptations. The clamp brackets 50L and 50R are installed after the adaptor has been plugged through the opening 16-0 in cover plate 16. It is an aspect and feature of this invention that the cover 16 can remain in place during all or a portion of the modification of the meter box to pilfer proof same. Of course, since it is a ringless type meter box, the cover must be removed in order to unplug the meter from the terminal block set. After the clamp brackets 50L and 50R have been installed with the legs or arms thereof positioned behind the meter stop brackets 26 and 27, a cast aluminum ring 70 having a first annulus portion 110-1 which rests upon meter stops 26 and 27, an annular flange 72 which abuts on the outer annular rib 25S of cover 25 and thus seals this space against surreptitious entry, and at outer annular ring 73 of smaller diameter than flange 70 for engagement with the base of the meter 20 so that the clamping ring 90 can be applied thereto. A tab 74-T is integrally formed with the ring 70 projects downwardly on the inside behind the cover 25 and a threaded screw 75 threadably engaged with tapped hole 75 has a shank portion 74-1 which projects behind the front surface of panel 25 to thereby serve as an additional positioning element for ring 70. The inner periphery of the ring at the 3 and 9 o'clock positions thereof (FIG. 5) is provided with a pair of internally projecting lugs 77-L and 77-R which have elongated slots 78-L and 78-R through which long bolts 79-L and 79-R (FIG. 2) pass to threadably engage with threaded and tapped holes 50-LO and 50-RO in clamp bars 50L and 50R, respectively, so that when these bolts are tightened, the meter stop brackets 26 and 27 are tightly clamped between the lower edge of ring 70 and the legs of the clamp bars 50 as shown clearly in FIG. 2. Meter cover 25 is thus secured against surreptitious opening and when the meter is in place there are no exposed screws or other fasteners which would permit easy access by those with a proclivity to pilfer electricity. After the securely tightening of these screws, the screws 87L and 87R may then be tightened by screwdriver or a coin. After this is done, the protective safety shield 90 is removed and the meter then can be plugged into the female socket elements of the adaptor 40 and the locking ring 100 then clamp to the ring 75. As noted above, if the customer is to be prevented from using electricity from the utility, a pair of insulated sleeves disconnects may be placed on the load side of the meter made connectors so that when the meter is replaced, the insulation sleeves prevent current flow to the customer. As shown in FIG. 8, the female-male contacts are formed of a single copper bar which has been folded approximate the center to form the male prongs 40MP which pass through slits 40S of insulating molded carriers 40 and within the lateral ends of wall W. A spring clip 40SC is inserted between the legs 40L1 and 40L2 such that the spring bearing points 40BP1 and 50BP2 bear on contact legs 40L3 and 40L4. When the male contacts 24,24 and 25,25 of the meter are inserted into the contact 40 and force the legs 40L3 and 40L4 apart, the spring clip is loaded and maintain a uniform pressure and avoids hot spots, etc. A spring pin SP passes through a hole 40H in the male plug side to retain the male/female plug in place; wall W provides some support for this male/female plug element. The locking ring or sealing ring 90 is applied over the shoulder on the glass cover of the meter and the locking flange 73 to thereby lock and seal the meter to the projecting collar 72 in flange 73. Thus, the meter cannot be removed without a key and/or otherwise damaging the unit to gain access to the meter and thereby pilfer electricity. The locking ring and its locking elements are conventional and are fully disclosed in Mylious Pat. No. 2,071,936. These devices include case hardened steel materials to resist cutting and hacksawing and in addition to accepting pad locks and other type of hard locking devices can also accept lead wire safety seals and the like for soft forms of protection. It will be appreciated that the objects of the invention have been satisfied in that no screw holes are required to be drilled for installation purposes and installation can take place in a short number of minutes because all that is required is (1) the removal of the meter and the ringless box cover, (2) insertion of the contact block adaptor with the protective covers in place, (3) attachment of the metal clamping bars to the adaptor, (4) replace the ringless box cover and position the cast aluminum ring 70 and secure same to the metal bars by the screws, (5) remove the protective covers from the female socket elements, (6) replace the meter (with or without the insulated disconnect sleeves DS), and (7) install the locking band. In some ringless meter boxes, the meter stop has a "Tee" shape (sometimes referred to as "Tee-type" meter stops. Referring to FIGS. 8 and 9, the bifurcated clamp bars 50BF have a flat body portion 190 which has an elongated slot 88BF through which screws or bolts 87-1 or 87-2 pass for engagements with threaded bore holes 85-1 or 85-2, respectively, in the steel bar 84 which is embedded in the insulated recess 83. The elongated slots 88BF permit the easy adjustment of the bifurcated clamp bars. The clamp bars are provided with a short angulated shank portion 191 and a common leg 192 which has a threaded perforation 50BF. Perforations 50BF are adapted to receive bolts 87L and 87R, respectively, passing through lug 72L and 72R on the locking ring collar 70. Bifurcation legs 193 and 194, respectively are joined to leg 192 by short extending members 195 and 196, respectively. The lengths of bifurcation legs 193 and 194 are such that they project outwardly and may be slid under the arms 197, 198 of the Tee-type meter stop 199. The arms 197 and 198 are secured by rivots 200 to the side edges or vertical ribs 201, 202 of meter box 11 and may actually slide under the edges or vertical ribs 201, 202. The clamp bars have an insulating coating 210 which is an electrical grade of an epoxy or PVC insulation 210 and which extends into and encloses the side openings of the slots 88BF and hole 50BF, it being appreciated that hole 50BF has a threaded opening which is for the purpose of receiving clamp screws 87L and 87R. As illustrated in the exploded view of FIG. 12, clamp screws 87L and 87R pass through openings in lugs in the locking ring and threadably engage with threaded holes 50BF so that when these clamping bolts 87 are tightened by a screwdriver, for example, the clamp bars bifurcated ends 193, 194 are spaced apart and bear at two spaced points on the undersides of the Tee legs 197, 198 and the edges 201 and 202 to more uniformly draw the annular flange 72 of the locking ring 70 tightly against the peripheral portions of cover 27 bounding meter opening 25S so as to tightly clamp the cover 27 shut with meter box 11. The meter then may be installed with or without the insulating sleeve disconnects and locked to the meter box with the locking ring 90. The locking ring 90 differs slightly from the locking ring shown in FIG. 1 in that the lock projects outwardly. However, both locking rings are commercially available for use with the present invention. Thus, the spacing of the bifurcated ends essentially provides a four-point engagement of the anchor bars with the meter stops and vertical edges of the meter box thereby providing a more balanced and improved securement and clamping of the cover and locking collar to the meter box per se. In addition, the insulating coating provides added safety to the installer as well as insurance against accidental contact of the internal metal parts with the "live" or "hot" wires to the anchor bars and thence to the meter box and meter box cover therefor and is a form of double insulation of the external metal parts relative to the pilfer proofing components added by this invention. While the invention has been particularly designed for pilfer proofing electric utility boxes while they are still connected to the electrical system, it will be appreciated that they can be applied to boxes prior to installation as a conversion kit. While there has been illustrated and described a preferred embodiment of the invention, it will be apparent to those skilled in the art that many modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims:
A pilfer proofing system for electric meter boxes having a meter base box which carries a plug-in terminal block set and a meter box cover having an opening through which a plug-in meter passes to engage contact female or socket terminals in a terminal block set. A contact terminal block adaptor carrying insulating cages frictionaly retained in the female socket terminal of the contact block set springs are included in the female socket terminals to assure continuous electrical contact and avoid hot spots. The meter box has a pair of lateral meter stops which are clamped between one end of an annular, cast aluminum ring and a pair of insulated, bifurcated clamp bars positioned behind the meter stops which, in turn, are secured to a common metal bar housed in a recess in the adaptor. The illustrate clamp bars have bifurcated ends which more evenly distributes the mechanical forces to the meter box by providing a plurality of distributed contact or load distribution points instead of one. An annular flange on the aluminum ring seals the edges of the existing opening in the meter cover thereby preventing surreptitious access to the interior of the meter box housing and, at the same time, clamping the rest of the meter cover securely to the box with the bifurcated clamp bars providing the plurality of distributed contact points.
Condense the core contents of the given document.
[ "REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. application Ser.", "No. 098,699 filed Sept.", "18, 1987, now abandoned, entitled "Pilfer Proofing System For Electric Utility Meter Box"", "which is a continuation-in-part of U.S. application Ser.", "No. 694,368 filed Jan. 24, 1985, entitled "Pilfer Proofing System And Method For Electric Utility Meter Box", now U.S. Pat. No. 4,615,113 which is a division of U.S. application Ser.", "No. 526,236 filed Aug. 25, 1983, now U.S. Pat. No. 4,505,530 which, in turn, is a division of U.S. application Ser.", "No. 170,205 filed Aug. 18, 1980, now U.S. Pat. No. 4,404,521, all of which are incorporated herein by reference.", "BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION In the above-referenced patent application and U.S. Pat. No. 4,404,521, 4,505,530, and 4,615,113 there is disclosed a pilfer proofing system and method for electric utility meter boxes which adapts existing ringless-type meter boxes to locking ring-type meter boxes without disconnecting the box from the incoming power lines.", "An objective of the present invention is to provide an improved pilfer proofing system that does not require the serviceman to drill any holes and which is faster and easier to install than the system disclosed in the above patents while retaining the key feature of being able to install the pilfer proofing system and convert the ringless-type meter boxes to a locking ring-type meter box without disconnecting the box from the incoming power lines e.g., while the meter box is electrified.", "According to this invention, a plug-in meter contact terminal block set adaptor as disclosed and claimed in the above U.S. Pat. No. 4,505,530 is used to carry an embedded metal bar which is secured to a pair of short meter stop clamp bars so as to expeditiously properly position the clamp bars behind the meter stops.", "A feature of the present invention is that the clamp bars, in one preferred embodiment, have bifurcated ends which slide under "Tee"-type meter stops, and also are coated with an electrical grade epoxy or PVC insulation.", "The bifurcation of the ends of the clamp bars provides a four point contact system for clamping the cover to the meter box and thereby enhances the security of the system, while at the same time, enlarging the types and range of meter boxes which can be safely, easily and quickly pilfer proofed by the invention at very low cost.", "A cast aluminum ring having an end adapted to abut the meter stop in the same way that the conventional meter abuts the meter stops, passes through the meter opening in the meter box cover to engage the meter stops and a pair of inwardly projecting lugs, integrally molded with the ring, are provided with elongated slots or holes through which pass locking bolts which engage threaded bores in the locking clamps.", "While the aluminum ring may be coated with an insulating coating, it is also grounded to the metal box.", "In another embodiment, the ring is a molded plastic element.", "When the bolts passing through the elongated slots in the cast aluminum ring are tightened, the meter stops are securely clamped between the metal clamp bars and the inner-most end of the annular ring.", "In the case of the bifurcated clamp bar ends, the end bifurcation may project under the cover edge at the meter opening so the clamp action may include that portion of the cover bounding the meter opening.", "The ring is provided with an enlarged annular flange which completely seals the opening in the meter box cover to prevent any surreptitious access thereto and a locating tab and set screw facilitate positioning the ring in place in the cover.", "Then the meter is plugged into the terminal block adaptor set and the locking ring or sealing band is applied over the shoulder of the meter itself and a locking flange on the cast annular ring to thereby lock and seal the meter to the projecting meter collar and flange.", "The operation can be done fast (about 3 minutes) and inexpensively, and there are no screws or drilling required to perform the installation.", "As noted above, the bifurcated clamp bar ends provide a four point contact with the meter stops and/or the edge of the meter box.", "Moreover, no special tools are required for installation, which can be done on a "live"", "meter box (no time is spent disconnecting service to the pole).", "Accordingly, the basic objective of the invention is to provide an improved pilfer proofing apparatus and method following the teachings of the above-identified related applications, which can be installed by the serviceman fast and inexpensively with only a screwdriver.", "BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, advantages and features of the invention will become more apparent when considered in conjunction with the following specification and accompanying drawings wherein: FIG. 1 is an exploded perspective view of a pilfer proof meter box incorporating the invention, FIG. 2 is a section line through a portion of the meter box showing the clamping or locking end of the adaptor components to the meter stops, FIG. 3 is a top plan view of the insulated carrier for the contact block socket adaptor assembly, FIG. 4 is a sectional view on lines 4--4 of FIG. 3, FIG. 5 is a plan view of the adaptor, FIG. 6 is a side view thereof, FIG. 7a is a top plan view of clamp bars, and FIG. 7b is a side elevational view thereof, FIG. 8 is a perspective view of the male-female elements carried by the contact set block adaptors, FIG. 9 is a top plan view of a bifurcated chamber which can be used for meter boxes having "Tee"-type meter stops, FIG. 10 is a sectional view on lines 10--10 of FIG. 9, FIG. 11 is a perspective view showing how the bifurcated clamp bar slides under the "Tee"-type meter stop, and FIG. 12 is an exploded view showing the installation with the bifurcated clamp bars.", "DETAILED DESCRIPTION OF THE INVENTION In the exploded perspective view of FIG. 1, an existing sheet metal meter box 10 has an input power cable 13 passing through gland 12 on the top 11 of box 10 with the electrical cables connected to the female contact jaws 16 and 17 of terminal block set 18 mounted on commercial base of box 10.", "Power to the user, which may be a home or commercial establishment, is supplied through conductors 19 which pass through a bottom gland 20 in the bottom 21 of box 10.", "With the meter 23 plugged-in with its upper male contacts 24 received in the female terminals 16 and 17 and the lower male terminals 25 plugged into the lower female terminals 26 [and 27] of the terminal block set 15, electrical power flows in through the conductor cable 13 through meter 23 and out through cable 19 to the user.", "The meter box cover 25 has an upper edge 25U sliding under a peripheral flange 26 on the top of box 10.", "Depending flanges or skirts 27 which fit over and closes off the edges of the two sidewalls and bottom wall of the meter box enclosure 10.", "Service to a customer may be terminated for various reasons.", "Various forms of insulated disconnect sleeves DS, as disclosed in U.S. Pat. No. 2,643,362 and 3,528,049, may be placed on the load sides of the male contact blades so that when the meter is plugged into the female sockets 16, 17 of the terminal block set 18, the customer will be prevented from receiving electrical power.", "In the usual case, prior to fitting the cover plate 25 onto the meter box 10, the meter unit 23 which has the rearwardly projecting contact blades 24,24 and 25,25 is plugged into the female contact jaws 16, 17 and 26, 27 in the terminal block set 18 as described above.", "A pair of meter stops 26 and 27 are secured to the sidewalls of meter box 10 by rivots or, preferably by welding.", "An annular shoulder 28 is formed at the base of glass cover 21 and a corresponding raised shoulder 25S is formed in the cover 25 so that when the cover 20 is fitted on the box 10, the glass meter cover 23 projects through the opening bounded by the flange 29 and annular shoulder 25S engages shoulder 28 to thereby retain the meter in place.", "A tongue 30 is secured to the bottom wall of meter box 10, and projects through a slot 31 in cover 25.", "A slide 32 secured to cover 25 has a projecting tongue 33 which has an aperture 34 which aligns with an aperture 35 in tongue 30.", "Slide 32 is positioned so that the two apertures 34 and 35 align and a safety seal (not shown) is used to provide an indication of tampering.", "As noted in the above related patents and related applications, in the past, those electric utility customers who have a proclivity to pilfer electricity have found it very easy to tamper with the safety seal (making it appear as if no tampering had taken place or easily disclaiming responsibility for the tampering) and easily gain access to the meter and tamper with same in various ways so as to bypass the meter and thereby inaccurately portray their actual electricity usage.", "In order to avoid this tampering, the invention utilizes essentially three components: I. a terminal block adaptor 40, II.", "a pair of clamp bars 50L and 50R having bifurcated ends, and III.", "an annular locking flange assembly 70.", "The contact terminal block adaptor 40 is similar in all major respects to the contact terminal block adaptor disclosed in the above-mentioned Fennell patents.", "The contact block adaptor 40 includes a molded insulating plastic carrier 40C (FIG.", "FIG. 4) which has a central pocket portion 83 in which is received a steel bar 84 that has a pair of bored and tapped holes 85-1, 85-2 aligned with holes 86-1 and 86-2 in the base of the pocket 83.", "A pair of clamp brackets 50L and 50R (shown in detail in FIGS. 7a and 7b) are secured in position on the bottom of pocket 83 by screw fasteners 87-1, 87-2 which pass through elongated slots 88-1 and 88-2, holes 86-1 and 86-2 and in threaded engagement with bored and tapped holes 85-1 and 85-2 to thereby adjustably mount brackets 50L and 50R on the adaptor 40.", "Brackets 50L and 50R have a shape such that their outermost ends 50LO and 50RO fit behind meter stops 26 and 27, respectively with a short straight section carrying a threaded and tapped holes 50LT and 50RT, the purpose of which will be described more fully hereafter.", "Since one of the prime objectives of the invention is to be able to pilfer proof a box while it is still connected to the line without danger to the serviceman, the upper female contacts 82, 83 in the adaptor 40 are protected by a safety shield 90 (FIG.", "8) which in conjunction with walls or barriers W insulates these "hot"", "(electrically) conductor elements during the pilfer proofing operation.", "Safety shield 90 (which is functionally similar to the safety shield shown in the above related patents) has a pair of non-conductive blade members 90B for frictionally retaining the shield in place in the hot conductor elements while the clamp brackets 50L and 50R are being installed in the manner described above.", "The plastic cover or cap 90 in this case can be similar in construction to the meter disconnect device disclosed in U.S. Pat. No. 3,614,708 and has a handle H thereon for safe and easy removal of cover 90 after the installation of the pilfer proofing adaptations.", "The clamp brackets 50L and 50R are installed after the adaptor has been plugged through the opening 16-0 in cover plate 16.", "It is an aspect and feature of this invention that the cover 16 can remain in place during all or a portion of the modification of the meter box to pilfer proof same.", "Of course, since it is a ringless type meter box, the cover must be removed in order to unplug the meter from the terminal block set.", "After the clamp brackets 50L and 50R have been installed with the legs or arms thereof positioned behind the meter stop brackets 26 and 27, a cast aluminum ring 70 having a first annulus portion 110-1 which rests upon meter stops 26 and 27, an annular flange 72 which abuts on the outer annular rib 25S of cover 25 and thus seals this space against surreptitious entry, and at outer annular ring 73 of smaller diameter than flange 70 for engagement with the base of the meter 20 so that the clamping ring 90 can be applied thereto.", "A tab 74-T is integrally formed with the ring 70 projects downwardly on the inside behind the cover 25 and a threaded screw 75 threadably engaged with tapped hole 75 has a shank portion 74-1 which projects behind the front surface of panel 25 to thereby serve as an additional positioning element for ring 70.", "The inner periphery of the ring at the 3 and 9 o'clock positions thereof (FIG.", "5) is provided with a pair of internally projecting lugs 77-L and 77-R which have elongated slots 78-L and 78-R through which long bolts 79-L and 79-R (FIG.", "2) pass to threadably engage with threaded and tapped holes 50-LO and 50-RO in clamp bars 50L and 50R, respectively, so that when these bolts are tightened, the meter stop brackets 26 and 27 are tightly clamped between the lower edge of ring 70 and the legs of the clamp bars 50 as shown clearly in FIG. 2. Meter cover 25 is thus secured against surreptitious opening and when the meter is in place there are no exposed screws or other fasteners which would permit easy access by those with a proclivity to pilfer electricity.", "After the securely tightening of these screws, the screws 87L and 87R may then be tightened by screwdriver or a coin.", "After this is done, the protective safety shield 90 is removed and the meter then can be plugged into the female socket elements of the adaptor 40 and the locking ring 100 then clamp to the ring 75.", "As noted above, if the customer is to be prevented from using electricity from the utility, a pair of insulated sleeves disconnects may be placed on the load side of the meter made connectors so that when the meter is replaced, the insulation sleeves prevent current flow to the customer.", "As shown in FIG. 8, the female-male contacts are formed of a single copper bar which has been folded approximate the center to form the male prongs 40MP which pass through slits 40S of insulating molded carriers 40 and within the lateral ends of wall W. A spring clip 40SC is inserted between the legs 40L1 and 40L2 such that the spring bearing points 40BP1 and 50BP2 bear on contact legs 40L3 and 40L4.", "When the male contacts 24,24 and 25,25 of the meter are inserted into the contact 40 and force the legs 40L3 and 40L4 apart, the spring clip is loaded and maintain a uniform pressure and avoids hot spots, etc.", "A spring pin SP passes through a hole 40H in the male plug side to retain the male/female plug in place;", "wall W provides some support for this male/female plug element.", "The locking ring or sealing ring 90 is applied over the shoulder on the glass cover of the meter and the locking flange 73 to thereby lock and seal the meter to the projecting collar 72 in flange 73.", "Thus, the meter cannot be removed without a key and/or otherwise damaging the unit to gain access to the meter and thereby pilfer electricity.", "The locking ring and its locking elements are conventional and are fully disclosed in Mylious Pat. No. 2,071,936.", "These devices include case hardened steel materials to resist cutting and hacksawing and in addition to accepting pad locks and other type of hard locking devices can also accept lead wire safety seals and the like for soft forms of protection.", "It will be appreciated that the objects of the invention have been satisfied in that no screw holes are required to be drilled for installation purposes and installation can take place in a short number of minutes because all that is required is (1) the removal of the meter and the ringless box cover, (2) insertion of the contact block adaptor with the protective covers in place, (3) attachment of the metal clamping bars to the adaptor, (4) replace the ringless box cover and position the cast aluminum ring 70 and secure same to the metal bars by the screws, (5) remove the protective covers from the female socket elements, (6) replace the meter (with or without the insulated disconnect sleeves DS), and (7) install the locking band.", "In some ringless meter boxes, the meter stop has a "Tee"", "shape (sometimes referred to as "Tee-type"", "meter stops.", "Referring to FIGS. 8 and 9, the bifurcated clamp bars 50BF have a flat body portion 190 which has an elongated slot 88BF through which screws or bolts 87-1 or 87-2 pass for engagements with threaded bore holes 85-1 or 85-2, respectively, in the steel bar 84 which is embedded in the insulated recess 83.", "The elongated slots 88BF permit the easy adjustment of the bifurcated clamp bars.", "The clamp bars are provided with a short angulated shank portion 191 and a common leg 192 which has a threaded perforation 50BF.", "Perforations 50BF are adapted to receive bolts 87L and 87R, respectively, passing through lug 72L and 72R on the locking ring collar 70.", "Bifurcation legs 193 and 194, respectively are joined to leg 192 by short extending members 195 and 196, respectively.", "The lengths of bifurcation legs 193 and 194 are such that they project outwardly and may be slid under the arms 197, 198 of the Tee-type meter stop 199.", "The arms 197 and 198 are secured by rivots 200 to the side edges or vertical ribs 201, 202 of meter box 11 and may actually slide under the edges or vertical ribs 201, 202.", "The clamp bars have an insulating coating 210 which is an electrical grade of an epoxy or PVC insulation 210 and which extends into and encloses the side openings of the slots 88BF and hole 50BF, it being appreciated that hole 50BF has a threaded opening which is for the purpose of receiving clamp screws 87L and 87R.", "As illustrated in the exploded view of FIG. 12, clamp screws 87L and 87R pass through openings in lugs in the locking ring and threadably engage with threaded holes 50BF so that when these clamping bolts 87 are tightened by a screwdriver, for example, the clamp bars bifurcated ends 193, 194 are spaced apart and bear at two spaced points on the undersides of the Tee legs 197, 198 and the edges 201 and 202 to more uniformly draw the annular flange 72 of the locking ring 70 tightly against the peripheral portions of cover 27 bounding meter opening 25S so as to tightly clamp the cover 27 shut with meter box 11.", "The meter then may be installed with or without the insulating sleeve disconnects and locked to the meter box with the locking ring 90.", "The locking ring 90 differs slightly from the locking ring shown in FIG. 1 in that the lock projects outwardly.", "However, both locking rings are commercially available for use with the present invention.", "Thus, the spacing of the bifurcated ends essentially provides a four-point engagement of the anchor bars with the meter stops and vertical edges of the meter box thereby providing a more balanced and improved securement and clamping of the cover and locking collar to the meter box per se.", "In addition, the insulating coating provides added safety to the installer as well as insurance against accidental contact of the internal metal parts with the "live"", "or "hot"", "wires to the anchor bars and thence to the meter box and meter box cover therefor and is a form of double insulation of the external metal parts relative to the pilfer proofing components added by this invention.", "While the invention has been particularly designed for pilfer proofing electric utility boxes while they are still connected to the electrical system, it will be appreciated that they can be applied to boxes prior to installation as a conversion kit.", "While there has been illustrated and described a preferred embodiment of the invention, it will be apparent to those skilled in the art that many modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims:" ]
RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 12/399,893 filed Mar. 6, 2009, titled “TRANSPORTATION DEVICE WITH PIVOTING AXLE”, which claims benefit under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 61/064,458, filed Mar. 6, 2008, entitled “TRANSPORTATION DEVICE WITH PIVOTING AXLE”, the entireties of which are hereby incorporated by reference herein and made a part of this specification. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to conveyances including skateboards, scooters, roller skates, as well as low profile skateboards, low profile roller skates, and other forms of conveyances. Some embodiments can include skateboards having a unitary platform with one or more inclined planar surfaces that serve as bearing surfaces for steerable axles and wheels. 2. Description of the Related Art There is a great deal of prior art describing various human powered platforms that can be turned by tilting the platform about an axis parallel to the direction of travel. For these devices, when the rider tilts the platform from side to side, one or two sets of wheels are induced to turn about an axis which is not parallel with the ground. In this way, skateboarders “lean into the turn in a way that facilitates balance during turns. Both skateboards and roller skates may include this type of tilt-based turning. In order to mechanically link tilting of the platform with turning of the wheels about a vertical axis, skateboards include a device called a truck. Conventional skateboard trucks are formed from metal or plastic, and are bulky, and usually contain four primary-components: a truck hanger, a base plate, a kingpin, and bushings. These trucks are conventionally located under the horizontal platform that the rider stands on, and the wheels are also usually located underneath the platform. Examples of a conventional skateboard truck include the Randal R-II, or the Destructo Mid Raw 5.0 Skateboard Truck. In the past, some skateboards have been designed to be used and then conveniently and easily carried with the user when the user is not riding the skateboard. Various features have been designed to meet this portability objective: skateboards that are of low weight, are foldable, are collapsible, or are readily disassembled. However, these skateboards have employed, for the most part, conventional trucks. Collapsible push scooters including those with lowered platforms are popular. Some of these have relatively short distance between the road surface and top of the riding platform. These scooters are typically made from metal, and although the steering handle collapses and folds, they are still bulky and cumbersome when in their most compact position. There are also a variety of skateboards available with lowered decks so that the rider can push the skateboard more readily. Therefore there is a need for conveyances with improved steering systems, including those that are lighter, more compact, and assembled from fewer parts. SUMMARY OF THE INVENTION Accordingly, in a first aspect, the invention provides a device for transportation comprising a platform comprising a ride surface upon which a rider may place a foot to ride the device in a direction of travel on the ground, so that the ride surface is an upper surface in use, the platform having a length extending in that direction and a forward portion and a rearward portion; a pair of wheels adjacent either the forward portion or the rearward portion and at least one wheel adjacent the other portion; an axle extending between the pair of wheels and located in an axle mounting system attached to the platform; the axle mounting system comprising an axle bearing surface and a pivot member having a pivot surface, the axle bearing surface and the pivot surface being inclined towards each other and each of the axle bearing surface and the pivot surface being inclined with respect to the ride surface, the pivot surface creating a pivot about which the axle can pivot to provide, in use, a turning function for the device and the axle bearing surface extending transversely to said length and providing a surface that supports the axle during said pivoting of the axle and turning of the device. Typically the axle mounting system is attached to and below the platform. Then, the axle bearing surface and pivot surface, in such preferred embodiments, are inclined towards each other towards the platform. In one embodiment, the axle bearing surface is located or extends adjacent each of the pair of wheels. This is to extend support to just inboard of the wheels, which in some embodiments are outside the perimeter of the foot of a rider. This reduces the bending stresses on the axle, and reduces the weight of the board. Thus, in one embodiment, the axle bearing surface has a length substantially the same as the length of the portion of the axle between the wheels. In one embodiment, the pivot member surface opposes the axle bearing surface. In one embodiment, the pivot member comprises a portion having a substantially triangular cross-section. In one embodiment, the surface of the pivot member is curved. In one embodiment, the axle bearing surface comprises a substantially planar portion. In one embodiment, the axle bearing surface comprises a curved portion. In one embodiment, the axle bearing surface comprises two or more substantially planar portions. In one embodiment, the location of the contact portion on the surface of the pivot member changes as the axle pivots about the pivot surface. In one embodiment, the location of the contact portion on the surface of the pivot member changes as the axle pivots about the pivot member surface, and the contact portions on the surface of the pivot member defined as the axle pivots describe a curve substantially parallel to a vertex of an angle between the surface of the pivot member and the bearing surface. In one embodiment, the bearing surface is a discontinuous surface. In one embodiment, the surface of the pivot member is a discontinuous surface. In one embodiment, the device further comprises a spring or spring like structure contacting the axle, and opposing the axle bearing surface. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a portion having a radius of curvature of about 140 to about 170 mm. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a central portion having a first radius of curvature, a first outboard portion having a second radius of curvature, and a second outboard portion having a third radius of curvature. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a central portion having a first radius of curvature, a first outboard portion having a second radius of curvature, and a second outboard portion having a third radius of curvature, wherein the first radius of curvature is greater than the second or third radii of curvature. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a central portion having a first radius of curvature, a first outboard portion having a second radius of curvature, and a second outboard portion having a third radius of curvature, wherein the first radius of curvature is greater than either of the outboard radii, the outboard radii preferably being equal to one another. Typically, the radius of curvature of the curved pivot member, whether as a constant curve, or the average radii of such multiple radii, is about 5 to 10 inches, preferably about 6-8 inches. In one embodiment, the angle between the pivot member surface and the axle bearing surface is about 70 to about 110°. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a central portion having a first radius of curvature, a first outboard portion having a second radius of curvature, and a second outboard portion having a third radius of curvature, wherein the first outboard portion and the second outboard portion are on opposite sides of the central portion. In one embodiment, the angle between the surface of the pivot member and the bearing surface measured at a central portion of the pivot member is different from the angle measured at an outboard portion of the pivot member. In one embodiment, the pair of wheels is adjacent the forward portion. In one embodiment, the pair of wheels is adjacent the rearward portion. In one embodiment, the platform has a top surface defining a first plane, the axle bearing surface forming an angle with a second plane parallel to the first plane being about 26 to about 45 degrees. In one embodiment, the platform has a top surface defining a first plane, the axle bearing surface forming an angle with a second plane parallel to the first plane being about 26 to 45 degrees, more preferably about 30 to about 40 degrees. In another embodiment, a method is presented for turning a transportation device, the method comprising pivoting an axle about a pivot member surface, wherein the pivot member surface contacts the axle and is disposed at an angle to a bearing surface and has a fixed position in relation to the bearing surface, the pivot member surface opposing the bearing surface and the bearing surface slidably contacting the axle, the axle extending between a pair of wheels positioned adjacent a forward portion or rearward portion of a ride surface suitable for placement of a rider's foot thereupon and the ride surface having at least one wheel adjacent the other portion of the ride surface. In another embodiment, there is provided a device for transportation comprising a platform upon which a rider may place a foot to ride the device in a direction of travel on the ground or similar surface, the platform having a length extending in that direction and a forward portion and a rearward portion; a pair of wheels adjacent either the forward portion or the rearward portion and at least one wheel adjacent the other portion; an axle extending between the pair of wheels and located in an axle mounting system attached to the platform, the axle being configured to pivot on an inclined surface, so that when a user leans to turn he device the platform tilts into the turn direction and the center of the top surface of the platform increases in altitude as the axle moves on the inclined surface to establishes a new position thereon. The inclined axle bearing surface may the other characteristics described herein. Preferably, the axle mounting system is attached to the underside of the platform. The device may further comprise a member about which the axle pivots as the axle moves on the inclined surface. The pivot member may a curved surface and/or the other characteristics described herein. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more fully understood from the following detailed description thereof taken in connection with the accompanying drawings, which form part of this application, and in which: FIG. 1 shows a perspective view of the underside of the skateboard with a rider's shoe placed in the riding position. FIG. 2 shows a perspective view of the front of the skateboard with the rider's shoe placed in the riding position. FIG. 3 shows a perspective view of the skateboard with the front left wheel removed to reveal the integral truck assembly. The primary elements of this truck are the inclined axle bearing surface 38 , the axle, 36 , the compression springs 44 R and 44 L, the pivot member 40 , and the axle retention device 45 . FIG. 4 shows a perspective view of the skateboard indicating how the integral truck produces a linkage between tilting of the platform about an axis parallel to the principle direction of travel and turning of the axis about an axis normal to the inclined axle bearing surface 38 . FIG. 5 shows a perspective view of a skateboard molded from a thermoplastic, with weight reduction features found in typical thermoplastic moldings, and molded flanges on the top surface of the platform intended to increase its resistance to bending about an axis parallel with the rear axle 50 . FIG. 6 shows a perspective view of a deadman's brake assembly, with the fender 48 partially cut away. FIG. 7 shows a perspective view of the axle 36 including a retention ring 64 L inboard from the left wheel that is used in conjunction with a second ring adjacent to the right wheel 64 R to keep the axle 36 from sliding parallel to its axis. FIG. 8 a shows a side view of a deadman's brake that is formed as an integral part of the unitary skateboard platform with this brake engaged to contact a wheel to stop the motion of the skateboard. FIG. 8 b shows a side view of the deadman's brake with the brake disengaged from the wheel by the application of a force F 2 to the brake by the application of pressure downward by the user's foot. FIG. 8 c shows a top view of this brake formed as an integral part of the unitary skateboard platform. FIG. 9 shows a perspective view of a skateboard an elastic strap 68 fastened to the underside of the platform. It also shows two partial front fenders 70 R and 70 L that are rigidly fixed to the foot support platform 32 to prevent the rider's foot from contacting the front wheels 34 R and 34 L. FIG. 10 shows a perspective view of a skateboard with the elastic strap 68 wrapped around the rider's shoe to held the shoe firmly to the top of the skateboard. FIG. 11 shows a view of a skateboard truck with an extended pivot member 80 , creating a gravity spring to provide forces that tend to restore the axle to the position normal to the centerline 82 of the skateboard. FIG. 12 shows the motion of the axle during a tilt induced turn, with the extended pivot member 80 . The point of contact between the axle 36 , and the extended pivot member 80 (the “pivot point”) shifts towards the wheel on the inside of the turn, where the term “inside” is defined in the conventional way. FIG. 13 shows a view of a non-planar inclined axle bearing surface comprising of two parts with differing slopes 88 A and 88 B. FIG. 14 shows a curved extended pivot member 90 . FIG. 15 shows an overmolded axle block 92 . This version of the axle block includes an integral curved extended pivot member that engages with the surface 39 , and a smooth planar section that is flush with the inclined axle bearing surface 38 . FIG. 16 shows the axle and curved pivot member. FIG. 17 is a front view of the skateboard showing the relative position of wheels and axle to the foot support platform. FIG. 18A is an oblique bottom view showing the curved pivot member and axle bearing surface. FIG. 18B is a side view showing the relative orientation of the curved pivot member and axle bearing surface to the ground. FIG. 19A is an oblique top view of one embodiment of the device showing the brake actuator and the fenders. FIG. 19B is a bottom view of one embodiment showing discontinuous surfaces for the axle bearing surface and the pivot member. FIG. 20A is an oblique bottom view of one embodiment showing discontinuous axle bearing and pivot member surfaces, vertex, and fenders. FIG. 20B is a side view of one embodiment showing relative angles of the angle between the pivot member surface and the bearing surface. FIG. 21 is a diagram of the device showing the components of the normal ray. FIG. 22 is a bottom view of the device showing the change in contact portion for different turning positions of the axle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The following description and examples illustrate some exemplary embodiments of the disclosed invention in detail. Those of skill in the art will recognize that there are numerous variations and modifications of this invention that are encompassed by its scope. Accordingly, the description of a certain exemplary embodiment should not be deemed to limit the scope of the present invention. In addition, the Figures are not to scale and some features may be exaggerated or minimized to show details of particular elements while related elements may have been eliminated to prevent obscuring other aspects. Generally speaking, the systems described herein are directed to wheeled conveyances including, for example, low profile wheeled conveyances, such as skateboards, scooters, kick scooters and/or roller skates. Referring to the Figures, some embodiments of the conveyance disclosed herein include a foot support platform 32 having an integral, full-width or partial-width inclined axle bearing surface 38 which supports a transverse axle 36 . In one embodiment, the inclined axle bearing surface 38 can be a planar surface and can form an angle of between about 10° and about 70° with the horizontal plane, said plane being defined as parallel to the travel surface depending, for example, on the steering responsiveness required. The axle 38 supports a pair of wheels 34 R and 34 L. The inclined axle bearing surface 38 supports the axle 36 across all or part of its span between the wheels 34 R and 34 L, but in some embodiments, said surface 38 can support the axle 36 in the regions adjacent to the wheels 34 R and 34 L and can reduce the bending moment applied to the axle. The wheels 34 R and 34 L can be conventional skateboard or roller skate or in-line skate or scooter wheels or other types of wheels, and in some embodiments a pair of roller or plain bearings, not depicted in these figures, can be located between the solid body of the wheel and the axle. The axle mayor may not rotate about its own longitudinal axis when the skateboard moves, and the wheels rotate. The axle can be offset from the center of the wheel in a vertical and/or horizontal direction, such as is shown in FIG. 17 . The wheels 34 R and 34 L may be retained at a specific location along the length of the axle 36 by any conventional means commonly used, including those used for skateboard, roller skate, in-line skate, or scooter wheels, but other methods can be used as well. The method of retention is not depicted here. A pair of compression springs 44 R and 44 L can be compressed by the axle 36 against a spring bearing surface 39 that can be an integral part or added part of the foot support platform. These springs may be rubber blocks, cell springs, leaf springs or any other type of member capable of supporting compression parallel to the surface of the inclined axle bearing surface 38 and perpendicular to the axle 36 . The compression springs serve to restore the axle to a position perpendicular to the long axis of the conveyance 82 (see FIG. 11 ), when no torque is applied by the user about said axis 82 . The compression springs therefore function to keep the conveyance running in a straight line or particular direction unless the user deliberately tilts the conveyance to make a turn or change the direction. In some embodiments, a turning bias can be built into the conveyance, such as by adjustment of the compression springs, the axle bearing surface or the pivot member design or position, such as to correct for an off-balance load, sloped travel surface, etc. or to favor, cause, or build-in a turning condition to the conveyance. In some embodiments, tension springs can be used in place of or in combination with compression springs. Suitable locations for tension springs include in front of and below the axle instead of the compression springs 44 R and 44 L. A pivoting axis 43 may be formed by the inclusion of a pivot member 40 formed in the shape of a triangular prism, or some other shape, including those which have a ridge configured to contact the axle. In some embodiments, springs for different rider weights, ability level, size, or performance can be provided with or separate from the conveyance for tuning the operation of the conveyance, or for other reasons, such as maintenance. In some embodiments, the spring response on operability can be adjusted, such as by including provision to adjust the lateral position of the springs on the spring bearing surface 39 . In some embodiments, a single rear wheel 46 can be supported by an axle 50 inserted through holes or indentations in the foot support platform, and retained by any conventional means. The wheel 46 can be positioned between the platform forks 49 R and 49 L and retained in an appropriate position by suitable methods including spacers, axle design features (such as interference fit, bumps, indentations, protuberances, etc.), nuts, etc. It is also possible to mold suitable spacers or other suitable features as part of the foot support platform 32 . In other embodiments, a single wheel, similar to that described for the rear can be utilized in the front with a system comprising an axle and inclined axle bearing surface, as described herein, in the rear, or a system comprising an axle and inclined axle bearing surface, as described herein, in both the front and the rear. A fender 48 can be included as part of a foot support platform to cover a single wheel 46 or a pair of wheels. The fender 48 could be molded as part of a foot support platform in a single molding operation, and can have sufficient rigidity to serve as a rest platform for a rider's ground engaging foot (the “pushing foot”). At the same time, the fender 48 could be designed with sufficient flexibility that it could engage the wheel to serve as a friction brake when a rider's weight was transferred from the front foot to the rear foot to press down substantially on said fender 48 . In some embodiments, fenders can be utilized, such as by molding as part of the foot support platform 32 or otherwise, for example to prevent the rider's foot from engaging the rotating wheels 34 R and 34 L. Partial front fenders 70 R and 70 L are shown in FIG. 9 and FIG. 10 . In some embodiments, fenders or partial fenders can prevent the axle from being unduly loaded in bending in the event that the user inadvertently stepped on the conveyance while it was upside down on the ground. An optional deadman's brake assembly can be composed from an angled lever 58 , a torsion spring 60 a depression 61 in the foot support platform body 32 and an axle 62 . If the user steps-off or falls off the conveyance, the torsion spring 60 presses the rear part of the angled lever 58 against the rear wheel 46 and slows or stops the conveyance Instead of using a torsion spring 60 , a compression spring may be inserted between the depression 61 in the foot support platform body 32 and the angled lever 58 to provide the deadman's brake action An alternative version of an optional deadman's brake is formed as an integral part of the foot support platform in order to reduce the number of parts and simplify assembly. For example, the brake 66 can be formed so that in the unstressed state it protrudes above the plane of the conveyance platform 32 and engages the rear wheel 46 as depicted in FIG. 8A . When the rider presses down on the brake 66 with his heel, then the brake shoe 66 disengages from the rear wheel 46 as depicted in FIG. 8B . In some embodiments, an axle bearing surface 38 can be positioned at an angle to a pivot member 40 , 80 or 90 . The bearing surface can be monoplanar as shown in FIG. 1 , or multiplanar or curved, as shown in FIG. 13 . In various embodiments, the curved or multiplanar character can be in a direction parallel to the long axis of the axle, at an angle to the long axis of the axle, or both parallel and at an angle to the long axis of the axle. In some embodiments, the axle bearing surface can extend substantially from one end of the axle to the other or from one wheel to the other. In some embodiments, the axle bearing surface can extend for a different distance over the length of the axle, such as 90% of the distance between the ends of the axle or the distance between the wheels, or for about 80% or for about 70% or for about 60% or for about 50% or for about 40% or for about 30% or for about 20% or less. As the extent of the axle bearing surface decreases, the axle can be made stronger, such as through dimensioning of the axle or through the selection of the materials used for the axle. Also, as the extent of the bearing surface decreases, the bearing surface can be made stronger, such as by selection of materials used for its construction. In some embodiments, the axle bearing surface can be removable, such as for replacement due to wear or to change the turning characteristics of the device, or for some other reasons including cosmetic. In some embodiments, the pivot member or its contact surface with the axle can be removable, such as for replacement due to wear or to change the turning characteristics of the device, or for some other reasons including cosmetic. Different shapes as well as materials and material hardness/resilience can be utilized for the bearing surface and the pivot member and pivot member surface, as desired such as for different turning or performance characteristics. The pivot member 40 can have a narrow contact region for contacting the axle, such as with a triangular cross-section as shown in FIG. 1 , or some other shape that presents a narrow or sharp surface to the axle. Suitable other shapes include those having a cross-section related to or including a square, rectangle, pentagon, teardrop, round or other shape. The narrow or sharp surface can also be truncated. In some embodiments, the pivot member can be a protruding portion from another part, such as the foot support platform a base structure, or another part. In one embodiment, as shown in FIG. 11 , the pivot member 40 defining a single pivot axis 43 is replaced with an extended pivot member 80 . The extended pivot member 80 is shaped so that the point or area of contact between the axle and the pivot member 80 shifts towards the inside of the turn, when the conveyance is tilted as depicted in FIG. 12 . A curved version of the extended pivot member 90 is depicted in FIG. 14 . Another version of a curved extended pivot member is shown in FIG. 16 , where the extended pivot member 90 has a curved face convex away from one end of the foot support platform. This curved face approaches or intersects the axle bearing surface 38 along a curved line 94 , where the ends of the curved line 94 curve upward and toward one end of the foot support platform 32 . In some embodiments, the pivot member 90 and the axle bearing surface 38 can be separated somewhat, such as with a gap or an intervening material, wherein the intervening material is flush, protrudes out, or is recessed from the surface of the pivot member 90 and/or the axle bearing surface 38 . In operation, when the rider leans or otherwise causes a turn, the foot support platform 32 will tip, with one edge of the foot support platform 32 moving toward the axle 36 , and the other edge moving away from the axle 36 . As the foot support platform 32 tips, the axle 36 shifts its contact zone 107 with the pivot member 90 to a new zone closer to the edge of the foot support platform on the side where the edge of the foot support platform 32 moved toward the axle, as shown in FIG. 22 . This axle movement results in the axle 36 pivoting with a component of the pivoting in a plane substantially parallel to plane of the travel surface or the top of the foot support platform 51 , with the wheel 34 R or 34 L at one end of the axle moving forward and the wheel 34 L or 34 R on the other end of the axle moving rearward, in relation to the direction of travel, causing a turning effect. Depending on the location and orientation of the axle bearing surface 38 and the pivot member 40 or 80 or 90 , the direction and magnitude of the turning effect can be varied, such as to be more sensitive, less sensitive, to turn in the direction of leaning or compression of the foot support platform 32 toward the axle 36 or away from the direction of leaning or compression of the foot support platform 32 toward the axle 36 . When the rider shifts position to move in a different direction, the contact zone 107 of the axle 36 with the pivot member 80 or 90 will shift as well, with the axle 36 contacting different points along the pivot member 80 or 90 related to the curved line 94 interface of the pivot member 80 or 90 and the axle bearing surface 38 . In FIG. 18A , an embodiment of a curved extended pivot member 80 having an approximately constant radius of curvature is shown. In other embodiments, the curved extended pivot member 90 can have a variable radius of curvature, such as with the central portion having a larger (flatter) radius of curvature than the outboard portions. Such a variable curvature can be advantageous, for example, in providing increased straight line stability, with minor shifts by a rider causing only small shifts in the axle position, while still allowing sharp turns. Suitable amounts of curvature include radii of about 80 to about 300 millimeters, while some embodiments can have radii of about 110 to about 220 mm or about 120 to about 180 mm, with some special embodiments having even higher or lower amounts of curvature. Suitable degrees of curvature can relate to the angle the bearing surface 38 forms with the horizontal plane, the sharpness of the turn desired, the dimensions of the foot support platform 32 , the size of the rider, etc. In FIG. 18B , the angular relationship of one embodiment of a curved extended pivot member 90 to an axle bearing surface 38 is shown. The included angle between the axle bearing surface 38 and the curved extended pivot member 40 can be any suitable angle, including angles of about 45 to about 135°. In some embodiments, the angle can be about 75 to about 110°, or about 85 to 95°. The angle between the axle bearing surface 38 and the horizontal plane 93 , can be about 10 to about 70°. In some embodiments, this angle can be about 20° to about 50°, or about 20° to about 40°, or about 25° to about 35°. Changes to either of these angles can provide the ability to, for example, adjust the turning response of the device as desired. In another embodiment, as illustrated in FIG. 13 , a pivot member with a ridge axle contact area is used, but the inclined axle bearing surface is no longer planar 88 A and 88 B. The mode of action will be described later in this document. In some embodiments, a non-planar inclined axle bearing surface can be combined with an extended pivot member or a curved extended pivot member. In some embodiments, the face of the extended pivot member or curved extended pivot member which has the axle contact area can be curved in both a horizontal and a vertical direction. In various embodiments, the nonplanar surface can be made of or approximate a number of planar surfaces, or it can be continually curved. In some embodiments, pivot member 40 is not included for the integral truck to function in the intended way. In the absence of a fixed pivoting axis 43 , the axle will float on the springs 44 R and 44 L, providing a compliant suspension. In some embodiments, the pivot member can be a pin or a rod. In some embodiments, the pivot member can contact the exterior of the axle, such as at a round, flat, grooved, dimpled, indented, etc. portion of the axle or covering; in some embodiments, the pivot member can contact the interior of the axle, such as in a hole; and in some embodiments, the pivot member can contact the interior and exterior of the axle. In some embodiments, the axle 36 can include a covering over at least a portion of its surface, and the pivot member can contact the exterior or interior of the covering portion of the axle 36 . The pivot member can be a pin protruding from the center of the axle 36 at a right angle or another angle to the axle, said pin can protrude into a hole or cavity formed in a middle portion of the inclined axle bearing surface 38 . In some embodiments, different locations for the pin in the axle, the axle bearing surface, or both, for various reasons including to modify the ride characteristics of the conveyance, to facilitate construction or assembly, etc. In some embodiments, more than one pin can be utilized. In some embodiments, the bearing surface can be a continuous or a discontinuous surface. Suitable discontinuous surfaces include those made up of a number of separated surfaces or surfaces interconnected with a different material or a recessed material. Individual surfaces can be made of like or unlike materials. Individual surfaces can be flat, curved, circular, rectangular, regular, a regular, interlocking, non-interlocking, or any other suitable shape as desired. In some embodiments, the surface of the pivot member can be a continuous or discontinuous surface as well. In some embodiments a continuous bearing surface can be utilized with a pivot member having a discontinuous surface, or a discontinuous bearing surface can be utilized with a pivot member having a continuous surface, or both the bearing surface and the surface of the pivot member can be either continuous or discontinuous. In some embodiments, the pivot member or the bearing surface can be made up of a series of individual parts, such as in the form of ridges protruding from a support material or a separate part. Examples of discontinuous faces on the axle bearing surface and the pivot member surface are shown in FIGS. 19B , 20 A and 22 . In FIG. 20A for example, the axle bearing surfaces and pivot members surfaces are formed by an opened cell network performed by a plurality of struts, which are chosen of a spacing and thickness of material sufficient to withstand relevant forces from the axle. FIGS. 20A and 22 show an extended curved surface 122 arranged symmetrically across the longitudinal access of the conveyance. As shown, the pivot surface extends a substantial proportion of the width of the device in this area. In these figures remaining in that area is shown in recessed portions 124 and 125 . In some embodiments, the device may have one or more handles attached to or formed therein. Such handles can aid in riding the device or performing maneuvers and/or can be used to attach pulling cords and the like. Preferably the forward end or front end of the device has an handle. The rear of the device may also have a handle, for example as is shown in FIGS. 19A , 19 B, ( 120 , 121 ). In some embodiments, the pivot member can be disposed at an angle to the bearing surface, such as where the bearing surface and the surface of the pivot member intersect at the vertex 106 of an angle, as shown in FIG. 20A . In one embodiment, the pivot member can be disposed at an angle to the bearing surface with a gap between the surface of the pivot member and the bearing surface, such as where a continuation of the pivot member surface or the bearing surface could intersect with the other. In one embodiment, additional material can be interposed between the surface of the pivot member and the bearing surface, such as in the vicinity of the vertex of the angle. In some embodiments, the entire pivot member and the bearing surface can be separated such as by a gap or by intervening material. In some embodiments, as shown in FIG. 21 , the surface of the pivot member can be located such that a ray 101 originating from a contact zone 107 of the axle 36 with the surface of the pivot member 90 , normal to the axle and passing through the axle centerline 105 (“normal ray”) has a component 102 substantially parallel to the direction of travel 104 . In some embodiments, the surface of the pivot member can oppose the bearing surface, such as where a normal ray intersects the bearing surface or intersects with a plane that would be an extension of an edge of the bearing surface or a plane that includes it is parallel to a portion of the bearing surface that contacts the axle. In FIG. 15 , an overmolded axle block 92 is depicted. This may be a simple rectangular prism used in conjunction with the springs and/or pivots described previously, or may incorporate an extended pivot member section as illustrated, including optional curved and non-curved portions. The axle block 92 can be integral to the axle, or assembled to the axle. The mode of action of the axle support unit with an inclined axle bearing support surface 38 is in some embodiments will now be described. In FIG. 4 , when a downward force 52 is imposed on the left front side of the platform, or a compressive force between the axle support unit and the axle, the left front wheel 34 L is forced rearward or forward, depending for example on the location and orientation of the inclined bearing surface 38 and the pivot member 40 or 80 or 90 , by the inclined axle bearing surface 38 that supports it, inducing a turn to the left or right, provided that the platform or board leans into the turn. As the downward or compressive force 52 is imposed, at least a portion of the axle 36 slides across the inclined axle bearing surface 38 and the axle pivots, a component of the rotation lying in a plane substantially parallel to the top surface of the foot support platform 32 . In some embodiments, an outboard portion of the axle 36 slides across the bearing surface. If the axle includes a covering, spacer, etc. which contacts the axle bearing surface 38 , the covering, spacer, etc. portion of the axle 36 will slide across the surface. The sliding motion can be described in some embodiments as an arc, a displacement, or a combination of an arc and a displacement. Hence the design can be set-up so the rider leans left and turns left, into his lean, facilitating a balancing and turning action similar to that of a conventional skateboard, or in some applications, he turns right when he leans left. In the drawings, the conveyance is represented as a three-wheeled device, with a single rear wheel, but it should be understood that the single rear wheel may be replaced by a second integral truck and wheel assembly which is the minor image of the front truck and wheel assembly about a plane whose normal vector is the long axis of the conveyance 82 . In some three-wheeled embodiments, the fender 48 , can serve as a platform for the rider to rest his pushing foot, when coasting down a hill for example. A four-wheeled device, can include a cantilevered beam, fixed with respect to the main riding platform and preferably molded as part of a foot support platform, protruding from the rear end of the foot support platform, behind the rider's heel, and can include such features as fender and brakes as desired. The rear fender 48 can be made to be flexible or compliant, so that with heavier pressure from the foot resting on it, it could serve as a brake by deforming and engaging with the rotating rear wheel 46 below it. An integral leaf spring could be formed in the elastic material of the fender to facilitate this motion. The entire fender could also be made to pivot around an axis parallel to but not coaxial with the rear axle, where resistance to pivoting would be supplied by a spring. In various embodiments, the fender would not engage the wheel with moderate pressure exerted by resting the rider's pushing foot during coasting, but would engage with heavier pressure applied by transferring weight to the pushing foot if the user wished to stop the conveyance. Resistance to the fender pivoting action could be applied by a torsion spring, or a rigid lever arm combined with a tension or compression spring. The compression springs 44 R and 44 L can be attached to the platform with an adhesive or adhesive tape, or can be retained in a slot or cavity molded or cut in the spring bearing surface 39 . The product may be provided with a set of springs of differing stiffuesses to accommodate riders of various weights. Such a set of springs may be color coded. Although the springs 44 R and 44 L in the various figures provided are depicted in a somewhat central location for clarity, in practice it would be advantageous to position them as close to the wheels 34 R and 34 L as possible, to minimize the bending moment on the axle 36 . Another method of providing variable resistance to turning can include placing the springs 44 R and 44 L in a slot formed in the spring bearing surface 39 , where the position of the springs along the axle 36 could be adjusted. If the springs 44 R and 44 L are moved towards the center of the spring bearing surface 39 (and closer to each other) the resistance to pivoting of the axle can be reduced, which might be desirable for a lighter rider. With the springs in wider positions (farther from each other), the resistance to pivoting of the axle can be increased, which might be desirable for a heavier rider. Higher resistance to pivoting can occur with the springs located directly adjacent to the wheels, 34 R and 34 L. However, a tradeoff can also be made with softer springs in a wider position to achieve similar or less resistance to pivoting as stronger springs in a narrower position. In this embodiment, it can be advantageous to have the springs seated in a slot formed in the spring bearing surface 39 , with sufficient friction to look them in place when the conveyance was in use, but sufficient clearance so that they could be shifted along said slot to adjust the turning resistance of the conveyance. Frequently in this description the full-width or partial-width inclined axle bearing surface 38 is described as formed as an integral part of the platform, however, it should be understood that even where the inclined axle bearing surface 38 is shown as full-width in all the drawings, the inclined bearing surface 38 can be narrower and can provide support to the axle 36 near the wheels, away from the wheels, or both near and away from the wheel, and the support for the axle can be continuous, or at discrete points over at least a portion of the length of the axle. Variations of these aspects of the design can provide additional benefits such as reducing the bending moment experienced by the axle over that experienced by axles in other designs. In some embodiments, the reduced bending moment of the axle 36 means that the axle can be of smaller diameter and lower cost and weight. In some embodiments, the inclined axle bearing surface 38 maybe cut away or not in contact with the axle 36 in the central part of the platform 32 , near the pivot member 40 or 80 or 90 . Further, the inclined axle bearing surface 38 is at various points shown and described as part of a unitary body, such as can be produced by injection molding the platform 32 and inclined axle bearing surface 38 in one shot from a suitable thermoplastic. However, it should be readily apparent that the inclined axle bearing surface 38 could be molded or formed from a different material and snapped or fastened to the main platform body 32 . For example, it may be desirable to have an inserted surface with low friction and/or high wear resistance. In addition, the body and/or platform can be made from multiple pieces and then assembled. It should be noted, however, that a unitary construction can have advantages of a higher resistance to bending than some other designs, and thus may be preferred in some cases, and can result in reduced the weight and cost, including fabrication costs of the conveyance while maintaining an adequate bending stiffness of the platform 32 . In one embodiment, leaf springs are integrally formed as part of the spring bearing surface 39 of the foot support platform 32 and replace springs 44 R and 44 L. This embodiment is dependent on the body of the unitary platform being constructed of a resilient, elastic material. In some embodiments, the platform can be attached to the rider's shoe such as with a flexible or semi-rigid strap 68 fastened to the body 32 somewhere between the front and rear wheels. Such a strap, lace or other attachment may be quickly fastened to itself with, for example, Velcro® on top of the rider's shoe, or otherwise. In some embodiments, a Velcro® patch or other releasable engagement means could be added to the sole of the rider's shoe to engage with its counterpart attached to the platform of the conveyance. In some embodiments, a special set of shoes with slots molded in their soles to engage a tab to be molded in the upper surface of the conveyance, or to provide engagement for a binding system such as is used for bicycles, skis, snowboards, etc. can be used. In some embodiments, various other attachment systems or devices can be used, such as those used for attaching a roller skate, ski, snowboard, water ski, or other conveyance to a shoe, boot, or foot may also be employed. A deadman's brake assembly is depicted in FIG. 6 , where the rear fender 48 has been cut-away for clarity. The torsion spring 60 causes the angled lever 58 to engage the rear wheel and slow or stop the conveyance when the rider falls or steps off. The point of contact of the angled lever with the wheel is designated the “friction pad.” When the rider is riding the conveyance, his or her heel can engage the front part of the angled lever 58 forcing it into a depression 61 formed in the platform 32 and disengaging it from the rear wheel 46 , allowing the conveyance to roll unimpeded. The angled lever 58 can be supported by an axle 62 . The torsion spring 60 could be replaced with a compression spring (coil, rubber, etc.) located, for example, between the horizontal portion of the angled lever 58 and the floor of the depression 61 in the platform body 32 . In FIG. 8 , an embodiment of a deadman's brake assembly in which the angled lever is replaced by a tab that is formed as an integral part of the platform 32 is depicted. This embodiment has the body of the foot support platform 32 being constructed of a resilient, elastic material that can deform elastically when the user's foot depresses the tab. In another embodiment, a material such as polypropylene, into which a living hinge can be molded could be used, with an optional secondary spring to provide at least a portion of the force that the deadman's brake applies to the wheel. The axle 36 , can be prevented from sliding side to side relative to the longitudinal axis 82 of the platform 32 . This may be accomplished in various ways. In one embodiment, a cylindrical pin is welded to the axle or screwed into a cavity in the axle such that the central axis of the cylindrical pin passes through a central area of the axle. Said pin protrudes from the axle, and fits in a hole formed in a corresponding portion of the inclined axle bearing surface 38 . In some embodiments, the pin can function as a pivot member 40 . In another embodiment, the axle can be positioned by two disks 64 L and 64 R fastened at a fixed axial position to the axle 36 between the wheels 34 L arid 34 R and the outermost edges of the inclined axle bearing surface 38 of the platform 32 , as depicted in FIG. 7 . When the rider is riding the conveyance and exerting a downward force on the platform, the axle can be held in its vertical location relative to the foot support platform 32 and the axle bearing surface 38 by the balance of forces; since the ground exerts an upward force on the axle through the wheels. In some embodiments it can also desirable to provide a means of retaining the axle in position relative to the inclined axle bearing surface 38 if the rider picks the conveyance off the ground. For example, in FIG. 3 , a rod 45 has been inserted in a hole drilled in the pivot member 40 . This rod 45 wraps underneath the axle 36 , and can, for example, hold the axle securely against the inclined axle bearing surface 38 or otherwise prevent the axle from falling off. In another example, as shown in FIG. 16 , a pin 94 passes through the axle 36 and a slot or hole 91 in the axle bearing surface 38 . Preferably, the slot will allow sufficient travel for the axle to move and turn in response to the efforts made by a rider to turn. A retention means could also be built into the compression springs 44 R and 44 L by having a protuberance in the springs hook around the underside of the axle. Alternatively, a band of the material of which the unitary platform 32 is constructed (not depicted) passing underneath the axle may be molded as an integral part of the unitary platform. It should be noted that the various retention devices shown can be used with the various pivot members and axle bearing surfaces described herein. In some embodiments, the axle 36 can be a solid or unitary cylinder. In some embodiments, the axle 36 can be non-solid, multi-piece, or a shape other than a cylinder. The axle can have any other cross-sectional shape, including square, rectangular, variable, etc., and the axle can be hollow, multi-part, a single piece, etc. In some embodiments, the axle can have one or more holes, cavities, indentations, extensions, protrusions or other shape features, such as for receiving a spring, a pin, an axle retention device, etc. or for other purpose, such as to contact a bearing surface or a pivot member. In some embodiments, a second material, such as a polymer or aluminum composition can be molded over the axle to form an axle block 92 in the region between the wheels 34 R and 34 L. Alternatively, the axle block may be a formed from a single material, with cylindrical axle segments formed from a second material or the same material protruding from either end. In either case, the axle block 92 could include a flat plane to sit flush on the inclined axle bearing surface 38 , or another shaped surface that can interface with a similar or matched surface of the axle bearing surface 38 , which in some embodiments can reduce wear on these surfaces. In some embodiments various features needed to retain the axle 36 and wheels laterally and vertically could be readily molded into the axle block. For example, a central locating pin transverse to the axle, or locating washers 64 L (and 64 R, not depicted) may be molded as part of the axle block. In some embodiments, the axle could be fitted with bearings or bushings near the wheels so that said bearings or bushings provide rolling contact with the inclined axle bearing surface 38 , in order to, for example, modify the steering response or reduce the wear and, friction associated with sliding of the axle 38 on the inclined axle bearing surface 38 . In some embodiments, sliding contact can be reduced or eliminated. Bearings can be used to support the axle at a more central position, or only at a position just inside the wheels, or additional bearings or wider or multi-race bearings can be use to provide support along more of the axle's width. In FIG. 15 , an overmolded axle block 92 is depicted. In some embodiments, this can be a simple rectangular prism used in conjunction with the springs and/or pivots described previously, or may incorporate an extended pivot member section as illustrated, including optional curved and non-curved portions. In some embodiments, a narrow surface similar to a pivot member 40 can be incorporated into an axle block or a broad surface similar to an extended pivot member 80 or a curved extended pivot member 90 . The axle block 92 can be integral to the axle, or assembled to the axle. In some embodiments, a substantial portion of a conveyance can be molded out of a plastic material or a thermoplastic fiber reinforced thermoplastic composite as a single piece or as a small number of pieces for assembly, such as, the foot support platform 32 , the rear fender 48 , the inclined axle bearing surface 38 , the pivot member 4 G, any special means for retaining the compression springs 44 L and 44 R, the deadman's brake 60 , and other features could all be molded in a single injection molding operation. In some embodiments, all or a portion of the parts can be produced separately. In some embodiments, some of these parts can be left out, for example the rear fender 48 , the deadman's brake 60 , or other features or combinations of features as desired. Such molding can result in reduces cost and/or reduced weight of the conveyance. In some embodiments, features can be designed to simultaneously increase the stiffness and strength of the conveyance, while reducing the cost and amount of material, used. In FIG. 5 , examples of molded-in cavities 54 are depicted. Variations of the design of molded-in cavities are possible, such as are used in the production of various items including those found in the lower leg assembly of a pedestal office chair, where said assembly was molded from a thermoplastic. In some embodiments, an extended flanges 56 on the central portion of the platform 32 in FIG. 5 can be incorporated, for example, to increase the bending stiffness of the foot support platform 32 about an-axis parallel to the rear axle. In some embodiments, portions of the device can be made from wood, metal, or some other appropriate material having appropriate characteristics of weight, stiffness and durability. In some embodiments, all or portions of the device can be machined, such as out of plastic, fiber reinforced plastic, metal, or wood. In some embodiments, parts can be cast or stamped out of metal. Suitable metal for construction of the device include steels and alloys of steel, nickel and/or chromium containing materials, aluminum, titanium, copper, brass, bronze, etc. In some embodiments, a lighter material can be utilized for a portion of the device and a harder or more durable material for another portion. Elastomers can be utilized for portions of the device as well. In some embodiments, a gravity or centrifugal force can be utilized to provide assistance in recovering the conveyance from a turn. A gravity or centrifugal force can be used in conjunction with springs, such as coil, leaf, elastomer, etc, or they can be used without springs. The recovery from turning can be induced without springs by, for example, ensuring that as the axle pivoted, the central portion of the foot support platform 32 was forced away from the axle (See FIG. 4 ). This case, the central portion of the foot support platform 32 would be forced to increase in altitude as the conveyance was tilted and the axle pivoted. (In this document, altitude is defined as the distance from the road surface, or a plane having an analogous relationship to the wheels as a road surface, along an axis normal to the road surface or plane.) The central portion of the foot support platform 32 would normally be at a lower altitude from the road surface or analogous plane, and its altitude would increase if the axle pivoted in either direction. A similar position restoring force can be provided by the centrifugal force experienced while turning the conveyance. This linkage between the pivoting action, and an altitude increase of the foot support platform is referred herein as a “gravity spring”, regardless of how it is accomplished. A gravity spring provides a restorative force to return the axle to its normal position substantially perpendicular to the centerline of the skateboard, and the skateboard travels in a substantially straight line unless the rider applies a torque about the centerline by leaning. Benefits with a gravity spring can include in some embodiments self-adjustment of a turn restorative force to the weight of a rider or load, reduced number of parts for construction of the conveyance, and elimination of parts subject to breakage or wear and requiring repair or replacement. First, the turn restorative force tending to return the front axle to its normal position relative to the long axis of the conveyance 82 with a gravity spring can be related to the weight of the user, potentially rendering one set of parts suitable for riders having a range of weights. Second, the need for springs is eliminated, reducing the number of parts used in manufacturing and assembling the conveyance, and eliminating springs or bushings that can break or wear out. In one embodiment, a gravity spring is made by using an elongated pivot member 80 or 90 rather than a single pivot point, as depicted in FIGS. 11 , 12 , 14 , 16 , 17 , 18 A and 18 B. In this method, the inclined axle bearing surface 38 can be planar, as in previously described embodiments, or otherwise, and the pivot member 80 or 90 is shaped so that as a compressive force is applied between the axle bearing surface 38 and the axle 36 , such as when the rider leans or shifts his weight, the pivot point (or point of contact between the axle 38 and the pivot member 80 or 90 ) shifts towards the wheel closest to the compressive force. This shift causes the axle to rotate in a plane parallel to the travel surface (i.e. turn). In some embodiments, the rotation of the axle can cause a turn in the direction of the lean or shift in weight as depicted in FIG. 12 . Since the pivot point is closer to the inside wheel (for this discussion, a system of lean left/turn left is assumed, but in some other embodiments, as with other parts of this description, this assumption can be reversed, as understood by one having skill in the art), as the axle 36 pivots, the rearward motion of the inside wheel is less than the forward motion of the outside wheel. Since the axle 36 is in contact with the inclined axle bearing surface 38 , the inside wheel moves towards the top surface 51 of the foot support platform 32 by an amount less than the distance that the outside wheel moves away from the top surface 51 of the-foot support platform 32 . The net result is that the distance between the central portion of the axle 36 and the nearest point on the top surface of the foot support platform 51 is increased when the axle 36 pivots, elevating the foot support platform and the rider. The center of the axle in the gravity spring, shifts down the axle bearing plane, moving it farther away from the top surface of the board, increasing the altitude of the deck, and providing a restorative force. The rider or load is closest to the road when the front axle 36 is perpendicular to the long axis of the conveyance 82 , and at least a portion of his foot or the load is elevated whenever the conveyance tilts and the axle pivots in either direction. This contributes to the desired gravity spring effect that induces the conveyance to level out so that it travels in a substantially straight line unless the rider supplies a torque around the long axis 82 of the conveyance. The magnitude of the centering force imposed by the gravity spring can depend on the width and shape of the pivot member, the angle of the inclined axle bearing surface, as well as other factors. For simplicity, a simple rectangular extended pivot member 80 is shown in FIGS. 11-12 , but this block could be rounded off, as long as pivoting of the axle 36 away from its position perpendicular to the long axis of the conveyance 82 produces a shift in the central portion of the foot support platform 32 away from the axle 36 . A suitable curved extended pivot member is depicted in FIG. 14 . Additional embodiments of curved extended pivot members are provided in FIGS. 16 , 17 , 18 A and 18 B. In some embodiments, an extended pivot member 80 or 90 can be attached to the axle 36 instead of molding it as part of, or fixing it rigidly to, a stationary part such as a portion of the foot support platform 32 or the spring bearing surface 39 . In some such embodiments, the spring bearing surface 39 or other portion that the axle block 92 interfaces with could he planar, and an axle block could be overmolded on the axle as described previously. The extended pivot member could be molded into the central region of the axle block 92 , and bear against the spring bearing surface 39 . Such an arrangement is depicted in FIG. 15 . Another embodiment of a gravity spring includes constructing the inclined axle bearing surface 38 to have a non-planar bearing surface as depicted in FIG. 13 . In this embodiment, the inclined axle bearing surface is curved or segmented ( 88 A and 88 B), and the slope of the rear part of the surface 88 B is less than the slope of the front part of the surface 88 A, where the slope is measured by the angle between the plane and the top surface 51 of the foot support platform 32 , however in some embodiments, the slopes of these two portions can be reversed, with the slope of the rear part of the surface 88 B being greater than the slope of the front part of the surface 88 A. In addition, other embodiments can have a greater number of differently sloped surfaces on the inclined axle bearing surface 38 , or a curved surface or a variably curved surface where the radius of curvature changes along the surface. As the axle is induced to pivot by tilting the platform about its long axis 82 , the inside wheel moves closer to the top surface 51 of the foot support platform 32 along the lesser slope of the rear part of the inclined axle bearing surface 88 B. (Here the terms “inside” and “outside” refer to the conventional definitions of the inside and outside of the turn.) Meanwhile the outside wheel moves farther from the top-surface 51 of the foot-support platform 32 along the greater slope of the forward part of the inclined axle bearing surface 88 A. Because of this, the outside wheel moves away from the top surface 51 by more than the inside wheel moves towards said top surface 51 , and the altitude of the center of the top surface 51 of the foot support platform increases. The inclined axle bearing surface can frequently be shaped so that the altitude of the center of the top surface of the foot support platform is lowest when the axle 36 is perpendicular to the long axis of the conveyance 82 or the altitude of the center of mass of the foot support platform 32 is lowest when the axle 36 is in its normal position, not influenced by an induced tilt of the foot support platform 32 . This creates a gravity-spring that causes the conveyance-to travel in a substantially straight line (or the conveyance's normal direction of travel) if it is not deliberately tilted around its long axis 82 through the application of torque by the rider. In some embodiments, the inclined axle bearing surface 88 can have a complex curvature designed to facilitate keeping most of the axle in contact with the inclined axle bearing surface 88 , regardless of the degree of pivot, which can have a larger slope towards the front of the conveyance, and a lesser slope towards the rear with a gravity spring unit mounted in the front portion of the conveyance and a larger slope towards the rear of the conveyance and a lesser slope towards the front with a gravity spring unit mounted in the rear portion of the conveyance. In some embodiments, a gravity-spring unit can be combined with a set of compression springs 44 R and 44 to create a combined force to restore the conveyance to substantially straight fine motion (or other normal travel direction as designed into the unit). The foregoing description of the preferred embodiments of the invention has been presented to illustrate the principles of the invention and not to limit the invention to the particular embodiment illustrated. It is intended that the scope of the invention be defined by all of the embodiments encompassed within the following claims and their equivalents. All references cited herein, including but not limited to published and unpublished applications, patents, and literature references, and also including but not limited to the references listed in the Appendix, are incorporated herein by reference in their entirety and are hereby made a part of this specification. To the extent publications and patents or patent applications incorporated by reference contradict the disclosure contained in the specification, the specification is intended to supersede and/or take precedence over any such contradictory material. The term “comprising” as used herein is synonymous with “including,” “containing,” or “characterized by,” and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. All numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth herein are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of any claims in any application claiming priority to the present application, each numerical parameter should be construed in light of the number of significant digits and ordinary rounding approaches. The above description discloses several methods and materials of the present invention. This invention is susceptible to modifications in the methods and materials, as well as alterations in the fabrication methods and equipment. Such modifications will become apparent to those skilled in the art from a consideration of this disclosure or practice of the invention disclosed herein. Consequently, it is not intended that this invention be limited to the specific embodiments disclosed herein, but that it cover all modifications and alternatives coming within the true scope and spirit of the invention.
Devices and methods of transport are disclosed. Various embodiments include structural aspects related to steering and changing the direction of conveyances including features which utilize leaning or shifting of weight as part of turning.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser.", "No. 12/399,893 filed Mar. 6, 2009, titled “TRANSPORTATION DEVICE WITH PIVOTING AXLE”, which claims benefit under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 61/064,458, filed Mar. 6, 2008, entitled “TRANSPORTATION DEVICE WITH PIVOTING AXLE”, the entireties of which are hereby incorporated by reference herein and made a part of this specification.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to conveyances including skateboards, scooters, roller skates, as well as low profile skateboards, low profile roller skates, and other forms of conveyances.", "Some embodiments can include skateboards having a unitary platform with one or more inclined planar surfaces that serve as bearing surfaces for steerable axles and wheels.", "Description of the Related Art There is a great deal of prior art describing various human powered platforms that can be turned by tilting the platform about an axis parallel to the direction of travel.", "For these devices, when the rider tilts the platform from side to side, one or two sets of wheels are induced to turn about an axis which is not parallel with the ground.", "In this way, skateboarders “lean into the turn in a way that facilitates balance during turns. Both skateboards and roller skates may include this type of tilt-based turning. In order to mechanically link tilting of the platform with turning of the wheels about a vertical axis, skateboards include a device called a truck. Conventional skateboard trucks are formed from metal or plastic, and are bulky, and usually contain four primary-components: a truck hanger, a base plate, a kingpin, and bushings. These trucks are conventionally located under the horizontal platform that the rider stands on, and the wheels are also usually located underneath the platform. Examples of a conventional skateboard truck include the Randal R-II, or the Destructo Mid Raw 5.0 Skateboard Truck. In the past, some skateboards have been designed to be used and then conveniently and easily carried with the user when the user is not riding the skateboard. Various features have been designed to meet this portability objective: skateboards that are of low weight, are foldable, are collapsible, or are readily disassembled. However, these skateboards have employed, for the most part, conventional trucks. Collapsible push scooters including those with lowered platforms are popular. Some of these have relatively short distance between the road surface and top of the riding platform. These scooters are typically made from metal, and although the steering handle collapses and folds, they are still bulky and cumbersome when in their most compact position. There are also a variety of skateboards available with lowered decks so that the rider can push the skateboard more readily. Therefore there is a need for conveyances with improved steering systems, including those that are lighter, more compact, and assembled from fewer parts. SUMMARY OF THE INVENTION Accordingly, in a first aspect, the invention provides a device for transportation comprising a platform comprising a ride surface upon which a rider may place a foot to ride the device in a direction of travel on the ground, so that the ride surface is an upper surface in use, the platform having a length extending in that direction and a forward portion and a rearward portion;", "a pair of wheels adjacent either the forward portion or the rearward portion and at least one wheel adjacent the other portion;", "an axle extending between the pair of wheels and located in an axle mounting system attached to the platform;", "the axle mounting system comprising an axle bearing surface and a pivot member having a pivot surface, the axle bearing surface and the pivot surface being inclined towards each other and each of the axle bearing surface and the pivot surface being inclined with respect to the ride surface, the pivot surface creating a pivot about which the axle can pivot to provide, in use, a turning function for the device and the axle bearing surface extending transversely to said length and providing a surface that supports the axle during said pivoting of the axle and turning of the device. Typically the axle mounting system is attached to and below the platform. Then, the axle bearing surface and pivot surface, in such preferred embodiments, are inclined towards each other towards the platform. In one embodiment, the axle bearing surface is located or extends adjacent each of the pair of wheels. This is to extend support to just inboard of the wheels, which in some embodiments are outside the perimeter of the foot of a rider. This reduces the bending stresses on the axle, and reduces the weight of the board. Thus, in one embodiment, the axle bearing surface has a length substantially the same as the length of the portion of the axle between the wheels. In one embodiment, the pivot member surface opposes the axle bearing surface. In one embodiment, the pivot member comprises a portion having a substantially triangular cross-section. In one embodiment, the surface of the pivot member is curved. In one embodiment, the axle bearing surface comprises a substantially planar portion. In one embodiment, the axle bearing surface comprises a curved portion. In one embodiment, the axle bearing surface comprises two or more substantially planar portions. In one embodiment, the location of the contact portion on the surface of the pivot member changes as the axle pivots about the pivot surface. In one embodiment, the location of the contact portion on the surface of the pivot member changes as the axle pivots about the pivot member surface, and the contact portions on the surface of the pivot member defined as the axle pivots describe a curve substantially parallel to a vertex of an angle between the surface of the pivot member and the bearing surface. In one embodiment, the bearing surface is a discontinuous surface. In one embodiment, the surface of the pivot member is a discontinuous surface. In one embodiment, the device further comprises a spring or spring like structure contacting the axle, and opposing the axle bearing surface. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a portion having a radius of curvature of about 140 to about 170 mm. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a central portion having a first radius of curvature, a first outboard portion having a second radius of curvature, and a second outboard portion having a third radius of curvature. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a central portion having a first radius of curvature, a first outboard portion having a second radius of curvature, and a second outboard portion having a third radius of curvature, wherein the first radius of curvature is greater than the second or third radii of curvature. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a central portion having a first radius of curvature, a first outboard portion having a second radius of curvature, and a second outboard portion having a third radius of curvature, wherein the first radius of curvature is greater than either of the outboard radii, the outboard radii preferably being equal to one another. Typically, the radius of curvature of the curved pivot member, whether as a constant curve, or the average radii of such multiple radii, is about 5 to 10 inches, preferably about 6-8 inches. In one embodiment, the angle between the pivot member surface and the axle bearing surface is about 70 to about 110°. In one embodiment, the surface of the pivot member is curved, and the curved surface of the pivot member comprises a central portion having a first radius of curvature, a first outboard portion having a second radius of curvature, and a second outboard portion having a third radius of curvature, wherein the first outboard portion and the second outboard portion are on opposite sides of the central portion. In one embodiment, the angle between the surface of the pivot member and the bearing surface measured at a central portion of the pivot member is different from the angle measured at an outboard portion of the pivot member. In one embodiment, the pair of wheels is adjacent the forward portion. In one embodiment, the pair of wheels is adjacent the rearward portion. In one embodiment, the platform has a top surface defining a first plane, the axle bearing surface forming an angle with a second plane parallel to the first plane being about 26 to about 45 degrees. In one embodiment, the platform has a top surface defining a first plane, the axle bearing surface forming an angle with a second plane parallel to the first plane being about 26 to 45 degrees, more preferably about 30 to about 40 degrees. In another embodiment, a method is presented for turning a transportation device, the method comprising pivoting an axle about a pivot member surface, wherein the pivot member surface contacts the axle and is disposed at an angle to a bearing surface and has a fixed position in relation to the bearing surface, the pivot member surface opposing the bearing surface and the bearing surface slidably contacting the axle, the axle extending between a pair of wheels positioned adjacent a forward portion or rearward portion of a ride surface suitable for placement of a rider's foot thereupon and the ride surface having at least one wheel adjacent the other portion of the ride surface. In another embodiment, there is provided a device for transportation comprising a platform upon which a rider may place a foot to ride the device in a direction of travel on the ground or similar surface, the platform having a length extending in that direction and a forward portion and a rearward portion;", "a pair of wheels adjacent either the forward portion or the rearward portion and at least one wheel adjacent the other portion;", "an axle extending between the pair of wheels and located in an axle mounting system attached to the platform, the axle being configured to pivot on an inclined surface, so that when a user leans to turn he device the platform tilts into the turn direction and the center of the top surface of the platform increases in altitude as the axle moves on the inclined surface to establishes a new position thereon. The inclined axle bearing surface may the other characteristics described herein. Preferably, the axle mounting system is attached to the underside of the platform. The device may further comprise a member about which the axle pivots as the axle moves on the inclined surface. The pivot member may a curved surface and/or the other characteristics described herein. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more fully understood from the following detailed description thereof taken in connection with the accompanying drawings, which form part of this application, and in which: FIG. 1 shows a perspective view of the underside of the skateboard with a rider's shoe placed in the riding position. FIG. 2 shows a perspective view of the front of the skateboard with the rider's shoe placed in the riding position. FIG. 3 shows a perspective view of the skateboard with the front left wheel removed to reveal the integral truck assembly. The primary elements of this truck are the inclined axle bearing surface 38 , the axle, 36 , the compression springs 44 R and 44 L, the pivot member 40 , and the axle retention device 45 . FIG. 4 shows a perspective view of the skateboard indicating how the integral truck produces a linkage between tilting of the platform about an axis parallel to the principle direction of travel and turning of the axis about an axis normal to the inclined axle bearing surface 38 . FIG. 5 shows a perspective view of a skateboard molded from a thermoplastic, with weight reduction features found in typical thermoplastic moldings, and molded flanges on the top surface of the platform intended to increase its resistance to bending about an axis parallel with the rear axle 50 . FIG. 6 shows a perspective view of a deadman's brake assembly, with the fender 48 partially cut away. FIG. 7 shows a perspective view of the axle 36 including a retention ring 64 L inboard from the left wheel that is used in conjunction with a second ring adjacent to the right wheel 64 R to keep the axle 36 from sliding parallel to its axis. FIG. 8 a shows a side view of a deadman's brake that is formed as an integral part of the unitary skateboard platform with this brake engaged to contact a wheel to stop the motion of the skateboard. FIG. 8 b shows a side view of the deadman's brake with the brake disengaged from the wheel by the application of a force F 2 to the brake by the application of pressure downward by the user's foot. FIG. 8 c shows a top view of this brake formed as an integral part of the unitary skateboard platform. FIG. 9 shows a perspective view of a skateboard an elastic strap 68 fastened to the underside of the platform. It also shows two partial front fenders 70 R and 70 L that are rigidly fixed to the foot support platform 32 to prevent the rider's foot from contacting the front wheels 34 R and 34 L. FIG. 10 shows a perspective view of a skateboard with the elastic strap 68 wrapped around the rider's shoe to held the shoe firmly to the top of the skateboard. FIG. 11 shows a view of a skateboard truck with an extended pivot member 80 , creating a gravity spring to provide forces that tend to restore the axle to the position normal to the centerline 82 of the skateboard. FIG. 12 shows the motion of the axle during a tilt induced turn, with the extended pivot member 80 . The point of contact between the axle 36 , and the extended pivot member 80 (the “pivot point”) shifts towards the wheel on the inside of the turn, where the term “inside”", "is defined in the conventional way.", "FIG. 13 shows a view of a non-planar inclined axle bearing surface comprising of two parts with differing slopes 88 A and 88 B. FIG. 14 shows a curved extended pivot member 90 .", "FIG. 15 shows an overmolded axle block 92 .", "This version of the axle block includes an integral curved extended pivot member that engages with the surface 39 , and a smooth planar section that is flush with the inclined axle bearing surface 38 .", "FIG. 16 shows the axle and curved pivot member.", "FIG. 17 is a front view of the skateboard showing the relative position of wheels and axle to the foot support platform.", "FIG. 18A is an oblique bottom view showing the curved pivot member and axle bearing surface.", "FIG. 18B is a side view showing the relative orientation of the curved pivot member and axle bearing surface to the ground.", "FIG. 19A is an oblique top view of one embodiment of the device showing the brake actuator and the fenders.", "FIG. 19B is a bottom view of one embodiment showing discontinuous surfaces for the axle bearing surface and the pivot member.", "FIG. 20A is an oblique bottom view of one embodiment showing discontinuous axle bearing and pivot member surfaces, vertex, and fenders.", "FIG. 20B is a side view of one embodiment showing relative angles of the angle between the pivot member surface and the bearing surface.", "FIG. 21 is a diagram of the device showing the components of the normal ray.", "FIG. 22 is a bottom view of the device showing the change in contact portion for different turning positions of the axle.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The following description and examples illustrate some exemplary embodiments of the disclosed invention in detail.", "Those of skill in the art will recognize that there are numerous variations and modifications of this invention that are encompassed by its scope.", "Accordingly, the description of a certain exemplary embodiment should not be deemed to limit the scope of the present invention.", "In addition, the Figures are not to scale and some features may be exaggerated or minimized to show details of particular elements while related elements may have been eliminated to prevent obscuring other aspects.", "Generally speaking, the systems described herein are directed to wheeled conveyances including, for example, low profile wheeled conveyances, such as skateboards, scooters, kick scooters and/or roller skates.", "Referring to the Figures, some embodiments of the conveyance disclosed herein include a foot support platform 32 having an integral, full-width or partial-width inclined axle bearing surface 38 which supports a transverse axle 36 .", "In one embodiment, the inclined axle bearing surface 38 can be a planar surface and can form an angle of between about 10° and about 70° with the horizontal plane, said plane being defined as parallel to the travel surface depending, for example, on the steering responsiveness required.", "The axle 38 supports a pair of wheels 34 R and 34 L. The inclined axle bearing surface 38 supports the axle 36 across all or part of its span between the wheels 34 R and 34 L, but in some embodiments, said surface 38 can support the axle 36 in the regions adjacent to the wheels 34 R and 34 L and can reduce the bending moment applied to the axle.", "The wheels 34 R and 34 L can be conventional skateboard or roller skate or in-line skate or scooter wheels or other types of wheels, and in some embodiments a pair of roller or plain bearings, not depicted in these figures, can be located between the solid body of the wheel and the axle.", "The axle mayor may not rotate about its own longitudinal axis when the skateboard moves, and the wheels rotate.", "The axle can be offset from the center of the wheel in a vertical and/or horizontal direction, such as is shown in FIG. 17 .", "The wheels 34 R and 34 L may be retained at a specific location along the length of the axle 36 by any conventional means commonly used, including those used for skateboard, roller skate, in-line skate, or scooter wheels, but other methods can be used as well.", "The method of retention is not depicted here.", "A pair of compression springs 44 R and 44 L can be compressed by the axle 36 against a spring bearing surface 39 that can be an integral part or added part of the foot support platform.", "These springs may be rubber blocks, cell springs, leaf springs or any other type of member capable of supporting compression parallel to the surface of the inclined axle bearing surface 38 and perpendicular to the axle 36 .", "The compression springs serve to restore the axle to a position perpendicular to the long axis of the conveyance 82 (see FIG. 11 ), when no torque is applied by the user about said axis 82 .", "The compression springs therefore function to keep the conveyance running in a straight line or particular direction unless the user deliberately tilts the conveyance to make a turn or change the direction.", "In some embodiments, a turning bias can be built into the conveyance, such as by adjustment of the compression springs, the axle bearing surface or the pivot member design or position, such as to correct for an off-balance load, sloped travel surface, etc.", "or to favor, cause, or build-in a turning condition to the conveyance.", "In some embodiments, tension springs can be used in place of or in combination with compression springs.", "Suitable locations for tension springs include in front of and below the axle instead of the compression springs 44 R and 44 L. A pivoting axis 43 may be formed by the inclusion of a pivot member 40 formed in the shape of a triangular prism, or some other shape, including those which have a ridge configured to contact the axle.", "In some embodiments, springs for different rider weights, ability level, size, or performance can be provided with or separate from the conveyance for tuning the operation of the conveyance, or for other reasons, such as maintenance.", "In some embodiments, the spring response on operability can be adjusted, such as by including provision to adjust the lateral position of the springs on the spring bearing surface 39 .", "In some embodiments, a single rear wheel 46 can be supported by an axle 50 inserted through holes or indentations in the foot support platform, and retained by any conventional means.", "The wheel 46 can be positioned between the platform forks 49 R and 49 L and retained in an appropriate position by suitable methods including spacers, axle design features (such as interference fit, bumps, indentations, protuberances, etc.), nuts, etc.", "It is also possible to mold suitable spacers or other suitable features as part of the foot support platform 32 .", "In other embodiments, a single wheel, similar to that described for the rear can be utilized in the front with a system comprising an axle and inclined axle bearing surface, as described herein, in the rear, or a system comprising an axle and inclined axle bearing surface, as described herein, in both the front and the rear.", "A fender 48 can be included as part of a foot support platform to cover a single wheel 46 or a pair of wheels.", "The fender 48 could be molded as part of a foot support platform in a single molding operation, and can have sufficient rigidity to serve as a rest platform for a rider's ground engaging foot (the “pushing foot”).", "At the same time, the fender 48 could be designed with sufficient flexibility that it could engage the wheel to serve as a friction brake when a rider's weight was transferred from the front foot to the rear foot to press down substantially on said fender 48 .", "In some embodiments, fenders can be utilized, such as by molding as part of the foot support platform 32 or otherwise, for example to prevent the rider's foot from engaging the rotating wheels 34 R and 34 L. Partial front fenders 70 R and 70 L are shown in FIG. 9 and FIG. 10 .", "In some embodiments, fenders or partial fenders can prevent the axle from being unduly loaded in bending in the event that the user inadvertently stepped on the conveyance while it was upside down on the ground.", "An optional deadman's brake assembly can be composed from an angled lever 58 , a torsion spring 60 a depression 61 in the foot support platform body 32 and an axle 62 .", "If the user steps-off or falls off the conveyance, the torsion spring 60 presses the rear part of the angled lever 58 against the rear wheel 46 and slows or stops the conveyance Instead of using a torsion spring 60 , a compression spring may be inserted between the depression 61 in the foot support platform body 32 and the angled lever 58 to provide the deadman's brake action An alternative version of an optional deadman's brake is formed as an integral part of the foot support platform in order to reduce the number of parts and simplify assembly.", "For example, the brake 66 can be formed so that in the unstressed state it protrudes above the plane of the conveyance platform 32 and engages the rear wheel 46 as depicted in FIG. 8A .", "When the rider presses down on the brake 66 with his heel, then the brake shoe 66 disengages from the rear wheel 46 as depicted in FIG. 8B .", "In some embodiments, an axle bearing surface 38 can be positioned at an angle to a pivot member 40 , 80 or 90 .", "The bearing surface can be monoplanar as shown in FIG. 1 , or multiplanar or curved, as shown in FIG. 13 .", "In various embodiments, the curved or multiplanar character can be in a direction parallel to the long axis of the axle, at an angle to the long axis of the axle, or both parallel and at an angle to the long axis of the axle.", "In some embodiments, the axle bearing surface can extend substantially from one end of the axle to the other or from one wheel to the other.", "In some embodiments, the axle bearing surface can extend for a different distance over the length of the axle, such as 90% of the distance between the ends of the axle or the distance between the wheels, or for about 80% or for about 70% or for about 60% or for about 50% or for about 40% or for about 30% or for about 20% or less.", "As the extent of the axle bearing surface decreases, the axle can be made stronger, such as through dimensioning of the axle or through the selection of the materials used for the axle.", "Also, as the extent of the bearing surface decreases, the bearing surface can be made stronger, such as by selection of materials used for its construction.", "In some embodiments, the axle bearing surface can be removable, such as for replacement due to wear or to change the turning characteristics of the device, or for some other reasons including cosmetic.", "In some embodiments, the pivot member or its contact surface with the axle can be removable, such as for replacement due to wear or to change the turning characteristics of the device, or for some other reasons including cosmetic.", "Different shapes as well as materials and material hardness/resilience can be utilized for the bearing surface and the pivot member and pivot member surface, as desired such as for different turning or performance characteristics.", "The pivot member 40 can have a narrow contact region for contacting the axle, such as with a triangular cross-section as shown in FIG. 1 , or some other shape that presents a narrow or sharp surface to the axle.", "Suitable other shapes include those having a cross-section related to or including a square, rectangle, pentagon, teardrop, round or other shape.", "The narrow or sharp surface can also be truncated.", "In some embodiments, the pivot member can be a protruding portion from another part, such as the foot support platform a base structure, or another part.", "In one embodiment, as shown in FIG. 11 , the pivot member 40 defining a single pivot axis 43 is replaced with an extended pivot member 80 .", "The extended pivot member 80 is shaped so that the point or area of contact between the axle and the pivot member 80 shifts towards the inside of the turn, when the conveyance is tilted as depicted in FIG. 12 .", "A curved version of the extended pivot member 90 is depicted in FIG. 14 .", "Another version of a curved extended pivot member is shown in FIG. 16 , where the extended pivot member 90 has a curved face convex away from one end of the foot support platform.", "This curved face approaches or intersects the axle bearing surface 38 along a curved line 94 , where the ends of the curved line 94 curve upward and toward one end of the foot support platform 32 .", "In some embodiments, the pivot member 90 and the axle bearing surface 38 can be separated somewhat, such as with a gap or an intervening material, wherein the intervening material is flush, protrudes out, or is recessed from the surface of the pivot member 90 and/or the axle bearing surface 38 .", "In operation, when the rider leans or otherwise causes a turn, the foot support platform 32 will tip, with one edge of the foot support platform 32 moving toward the axle 36 , and the other edge moving away from the axle 36 .", "As the foot support platform 32 tips, the axle 36 shifts its contact zone 107 with the pivot member 90 to a new zone closer to the edge of the foot support platform on the side where the edge of the foot support platform 32 moved toward the axle, as shown in FIG. 22 .", "This axle movement results in the axle 36 pivoting with a component of the pivoting in a plane substantially parallel to plane of the travel surface or the top of the foot support platform 51 , with the wheel 34 R or 34 L at one end of the axle moving forward and the wheel 34 L or 34 R on the other end of the axle moving rearward, in relation to the direction of travel, causing a turning effect.", "Depending on the location and orientation of the axle bearing surface 38 and the pivot member 40 or 80 or 90 , the direction and magnitude of the turning effect can be varied, such as to be more sensitive, less sensitive, to turn in the direction of leaning or compression of the foot support platform 32 toward the axle 36 or away from the direction of leaning or compression of the foot support platform 32 toward the axle 36 .", "When the rider shifts position to move in a different direction, the contact zone 107 of the axle 36 with the pivot member 80 or 90 will shift as well, with the axle 36 contacting different points along the pivot member 80 or 90 related to the curved line 94 interface of the pivot member 80 or 90 and the axle bearing surface 38 .", "In FIG. 18A , an embodiment of a curved extended pivot member 80 having an approximately constant radius of curvature is shown.", "In other embodiments, the curved extended pivot member 90 can have a variable radius of curvature, such as with the central portion having a larger (flatter) radius of curvature than the outboard portions.", "Such a variable curvature can be advantageous, for example, in providing increased straight line stability, with minor shifts by a rider causing only small shifts in the axle position, while still allowing sharp turns.", "Suitable amounts of curvature include radii of about 80 to about 300 millimeters, while some embodiments can have radii of about 110 to about 220 mm or about 120 to about 180 mm, with some special embodiments having even higher or lower amounts of curvature.", "Suitable degrees of curvature can relate to the angle the bearing surface 38 forms with the horizontal plane, the sharpness of the turn desired, the dimensions of the foot support platform 32 , the size of the rider, etc.", "In FIG. 18B , the angular relationship of one embodiment of a curved extended pivot member 90 to an axle bearing surface 38 is shown.", "The included angle between the axle bearing surface 38 and the curved extended pivot member 40 can be any suitable angle, including angles of about 45 to about 135°.", "In some embodiments, the angle can be about 75 to about 110°, or about 85 to 95°.", "The angle between the axle bearing surface 38 and the horizontal plane 93 , can be about 10 to about 70°.", "In some embodiments, this angle can be about 20° to about 50°, or about 20° to about 40°, or about 25° to about 35°.", "Changes to either of these angles can provide the ability to, for example, adjust the turning response of the device as desired.", "In another embodiment, as illustrated in FIG. 13 , a pivot member with a ridge axle contact area is used, but the inclined axle bearing surface is no longer planar 88 A and 88 B. The mode of action will be described later in this document.", "In some embodiments, a non-planar inclined axle bearing surface can be combined with an extended pivot member or a curved extended pivot member.", "In some embodiments, the face of the extended pivot member or curved extended pivot member which has the axle contact area can be curved in both a horizontal and a vertical direction.", "In various embodiments, the nonplanar surface can be made of or approximate a number of planar surfaces, or it can be continually curved.", "In some embodiments, pivot member 40 is not included for the integral truck to function in the intended way.", "In the absence of a fixed pivoting axis 43 , the axle will float on the springs 44 R and 44 L, providing a compliant suspension.", "In some embodiments, the pivot member can be a pin or a rod.", "In some embodiments, the pivot member can contact the exterior of the axle, such as at a round, flat, grooved, dimpled, indented, etc.", "portion of the axle or covering;", "in some embodiments, the pivot member can contact the interior of the axle, such as in a hole;", "and in some embodiments, the pivot member can contact the interior and exterior of the axle.", "In some embodiments, the axle 36 can include a covering over at least a portion of its surface, and the pivot member can contact the exterior or interior of the covering portion of the axle 36 .", "The pivot member can be a pin protruding from the center of the axle 36 at a right angle or another angle to the axle, said pin can protrude into a hole or cavity formed in a middle portion of the inclined axle bearing surface 38 .", "In some embodiments, different locations for the pin in the axle, the axle bearing surface, or both, for various reasons including to modify the ride characteristics of the conveyance, to facilitate construction or assembly, etc.", "In some embodiments, more than one pin can be utilized.", "In some embodiments, the bearing surface can be a continuous or a discontinuous surface.", "Suitable discontinuous surfaces include those made up of a number of separated surfaces or surfaces interconnected with a different material or a recessed material.", "Individual surfaces can be made of like or unlike materials.", "Individual surfaces can be flat, curved, circular, rectangular, regular, a regular, interlocking, non-interlocking, or any other suitable shape as desired.", "In some embodiments, the surface of the pivot member can be a continuous or discontinuous surface as well.", "In some embodiments a continuous bearing surface can be utilized with a pivot member having a discontinuous surface, or a discontinuous bearing surface can be utilized with a pivot member having a continuous surface, or both the bearing surface and the surface of the pivot member can be either continuous or discontinuous.", "In some embodiments, the pivot member or the bearing surface can be made up of a series of individual parts, such as in the form of ridges protruding from a support material or a separate part.", "Examples of discontinuous faces on the axle bearing surface and the pivot member surface are shown in FIGS. 19B , 20 A and 22 .", "In FIG. 20A for example, the axle bearing surfaces and pivot members surfaces are formed by an opened cell network performed by a plurality of struts, which are chosen of a spacing and thickness of material sufficient to withstand relevant forces from the axle.", "FIGS. 20A and 22 show an extended curved surface 122 arranged symmetrically across the longitudinal access of the conveyance.", "As shown, the pivot surface extends a substantial proportion of the width of the device in this area.", "In these figures remaining in that area is shown in recessed portions 124 and 125 .", "In some embodiments, the device may have one or more handles attached to or formed therein.", "Such handles can aid in riding the device or performing maneuvers and/or can be used to attach pulling cords and the like.", "Preferably the forward end or front end of the device has an handle.", "The rear of the device may also have a handle, for example as is shown in FIGS. 19A , 19 B, ( 120 , 121 ).", "In some embodiments, the pivot member can be disposed at an angle to the bearing surface, such as where the bearing surface and the surface of the pivot member intersect at the vertex 106 of an angle, as shown in FIG. 20A .", "In one embodiment, the pivot member can be disposed at an angle to the bearing surface with a gap between the surface of the pivot member and the bearing surface, such as where a continuation of the pivot member surface or the bearing surface could intersect with the other.", "In one embodiment, additional material can be interposed between the surface of the pivot member and the bearing surface, such as in the vicinity of the vertex of the angle.", "In some embodiments, the entire pivot member and the bearing surface can be separated such as by a gap or by intervening material.", "In some embodiments, as shown in FIG. 21 , the surface of the pivot member can be located such that a ray 101 originating from a contact zone 107 of the axle 36 with the surface of the pivot member 90 , normal to the axle and passing through the axle centerline 105 (“normal ray”) has a component 102 substantially parallel to the direction of travel 104 .", "In some embodiments, the surface of the pivot member can oppose the bearing surface, such as where a normal ray intersects the bearing surface or intersects with a plane that would be an extension of an edge of the bearing surface or a plane that includes it is parallel to a portion of the bearing surface that contacts the axle.", "In FIG. 15 , an overmolded axle block 92 is depicted.", "This may be a simple rectangular prism used in conjunction with the springs and/or pivots described previously, or may incorporate an extended pivot member section as illustrated, including optional curved and non-curved portions.", "The axle block 92 can be integral to the axle, or assembled to the axle.", "The mode of action of the axle support unit with an inclined axle bearing support surface 38 is in some embodiments will now be described.", "In FIG. 4 , when a downward force 52 is imposed on the left front side of the platform, or a compressive force between the axle support unit and the axle, the left front wheel 34 L is forced rearward or forward, depending for example on the location and orientation of the inclined bearing surface 38 and the pivot member 40 or 80 or 90 , by the inclined axle bearing surface 38 that supports it, inducing a turn to the left or right, provided that the platform or board leans into the turn.", "As the downward or compressive force 52 is imposed, at least a portion of the axle 36 slides across the inclined axle bearing surface 38 and the axle pivots, a component of the rotation lying in a plane substantially parallel to the top surface of the foot support platform 32 .", "In some embodiments, an outboard portion of the axle 36 slides across the bearing surface.", "If the axle includes a covering, spacer, etc.", "which contacts the axle bearing surface 38 , the covering, spacer, etc.", "portion of the axle 36 will slide across the surface.", "The sliding motion can be described in some embodiments as an arc, a displacement, or a combination of an arc and a displacement.", "Hence the design can be set-up so the rider leans left and turns left, into his lean, facilitating a balancing and turning action similar to that of a conventional skateboard, or in some applications, he turns right when he leans left.", "In the drawings, the conveyance is represented as a three-wheeled device, with a single rear wheel, but it should be understood that the single rear wheel may be replaced by a second integral truck and wheel assembly which is the minor image of the front truck and wheel assembly about a plane whose normal vector is the long axis of the conveyance 82 .", "In some three-wheeled embodiments, the fender 48 , can serve as a platform for the rider to rest his pushing foot, when coasting down a hill for example.", "A four-wheeled device, can include a cantilevered beam, fixed with respect to the main riding platform and preferably molded as part of a foot support platform, protruding from the rear end of the foot support platform, behind the rider's heel, and can include such features as fender and brakes as desired.", "The rear fender 48 can be made to be flexible or compliant, so that with heavier pressure from the foot resting on it, it could serve as a brake by deforming and engaging with the rotating rear wheel 46 below it.", "An integral leaf spring could be formed in the elastic material of the fender to facilitate this motion.", "The entire fender could also be made to pivot around an axis parallel to but not coaxial with the rear axle, where resistance to pivoting would be supplied by a spring.", "In various embodiments, the fender would not engage the wheel with moderate pressure exerted by resting the rider's pushing foot during coasting, but would engage with heavier pressure applied by transferring weight to the pushing foot if the user wished to stop the conveyance.", "Resistance to the fender pivoting action could be applied by a torsion spring, or a rigid lever arm combined with a tension or compression spring.", "The compression springs 44 R and 44 L can be attached to the platform with an adhesive or adhesive tape, or can be retained in a slot or cavity molded or cut in the spring bearing surface 39 .", "The product may be provided with a set of springs of differing stiffuesses to accommodate riders of various weights.", "Such a set of springs may be color coded.", "Although the springs 44 R and 44 L in the various figures provided are depicted in a somewhat central location for clarity, in practice it would be advantageous to position them as close to the wheels 34 R and 34 L as possible, to minimize the bending moment on the axle 36 .", "Another method of providing variable resistance to turning can include placing the springs 44 R and 44 L in a slot formed in the spring bearing surface 39 , where the position of the springs along the axle 36 could be adjusted.", "If the springs 44 R and 44 L are moved towards the center of the spring bearing surface 39 (and closer to each other) the resistance to pivoting of the axle can be reduced, which might be desirable for a lighter rider.", "With the springs in wider positions (farther from each other), the resistance to pivoting of the axle can be increased, which might be desirable for a heavier rider.", "Higher resistance to pivoting can occur with the springs located directly adjacent to the wheels, 34 R and 34 L. However, a tradeoff can also be made with softer springs in a wider position to achieve similar or less resistance to pivoting as stronger springs in a narrower position.", "In this embodiment, it can be advantageous to have the springs seated in a slot formed in the spring bearing surface 39 , with sufficient friction to look them in place when the conveyance was in use, but sufficient clearance so that they could be shifted along said slot to adjust the turning resistance of the conveyance.", "Frequently in this description the full-width or partial-width inclined axle bearing surface 38 is described as formed as an integral part of the platform, however, it should be understood that even where the inclined axle bearing surface 38 is shown as full-width in all the drawings, the inclined bearing surface 38 can be narrower and can provide support to the axle 36 near the wheels, away from the wheels, or both near and away from the wheel, and the support for the axle can be continuous, or at discrete points over at least a portion of the length of the axle.", "Variations of these aspects of the design can provide additional benefits such as reducing the bending moment experienced by the axle over that experienced by axles in other designs.", "In some embodiments, the reduced bending moment of the axle 36 means that the axle can be of smaller diameter and lower cost and weight.", "In some embodiments, the inclined axle bearing surface 38 maybe cut away or not in contact with the axle 36 in the central part of the platform 32 , near the pivot member 40 or 80 or 90 .", "Further, the inclined axle bearing surface 38 is at various points shown and described as part of a unitary body, such as can be produced by injection molding the platform 32 and inclined axle bearing surface 38 in one shot from a suitable thermoplastic.", "However, it should be readily apparent that the inclined axle bearing surface 38 could be molded or formed from a different material and snapped or fastened to the main platform body 32 .", "For example, it may be desirable to have an inserted surface with low friction and/or high wear resistance.", "In addition, the body and/or platform can be made from multiple pieces and then assembled.", "It should be noted, however, that a unitary construction can have advantages of a higher resistance to bending than some other designs, and thus may be preferred in some cases, and can result in reduced the weight and cost, including fabrication costs of the conveyance while maintaining an adequate bending stiffness of the platform 32 .", "In one embodiment, leaf springs are integrally formed as part of the spring bearing surface 39 of the foot support platform 32 and replace springs 44 R and 44 L. This embodiment is dependent on the body of the unitary platform being constructed of a resilient, elastic material.", "In some embodiments, the platform can be attached to the rider's shoe such as with a flexible or semi-rigid strap 68 fastened to the body 32 somewhere between the front and rear wheels.", "Such a strap, lace or other attachment may be quickly fastened to itself with, for example, Velcro® on top of the rider's shoe, or otherwise.", "In some embodiments, a Velcro® patch or other releasable engagement means could be added to the sole of the rider's shoe to engage with its counterpart attached to the platform of the conveyance.", "In some embodiments, a special set of shoes with slots molded in their soles to engage a tab to be molded in the upper surface of the conveyance, or to provide engagement for a binding system such as is used for bicycles, skis, snowboards, etc.", "can be used.", "In some embodiments, various other attachment systems or devices can be used, such as those used for attaching a roller skate, ski, snowboard, water ski, or other conveyance to a shoe, boot, or foot may also be employed.", "A deadman's brake assembly is depicted in FIG. 6 , where the rear fender 48 has been cut-away for clarity.", "The torsion spring 60 causes the angled lever 58 to engage the rear wheel and slow or stop the conveyance when the rider falls or steps off.", "The point of contact of the angled lever with the wheel is designated the “friction pad.”", "When the rider is riding the conveyance, his or her heel can engage the front part of the angled lever 58 forcing it into a depression 61 formed in the platform 32 and disengaging it from the rear wheel 46 , allowing the conveyance to roll unimpeded.", "The angled lever 58 can be supported by an axle 62 .", "The torsion spring 60 could be replaced with a compression spring (coil, rubber, etc.) located, for example, between the horizontal portion of the angled lever 58 and the floor of the depression 61 in the platform body 32 .", "In FIG. 8 , an embodiment of a deadman's brake assembly in which the angled lever is replaced by a tab that is formed as an integral part of the platform 32 is depicted.", "This embodiment has the body of the foot support platform 32 being constructed of a resilient, elastic material that can deform elastically when the user's foot depresses the tab.", "In another embodiment, a material such as polypropylene, into which a living hinge can be molded could be used, with an optional secondary spring to provide at least a portion of the force that the deadman's brake applies to the wheel.", "The axle 36 , can be prevented from sliding side to side relative to the longitudinal axis 82 of the platform 32 .", "This may be accomplished in various ways.", "In one embodiment, a cylindrical pin is welded to the axle or screwed into a cavity in the axle such that the central axis of the cylindrical pin passes through a central area of the axle.", "Said pin protrudes from the axle, and fits in a hole formed in a corresponding portion of the inclined axle bearing surface 38 .", "In some embodiments, the pin can function as a pivot member 40 .", "In another embodiment, the axle can be positioned by two disks 64 L and 64 R fastened at a fixed axial position to the axle 36 between the wheels 34 L arid 34 R and the outermost edges of the inclined axle bearing surface 38 of the platform 32 , as depicted in FIG. 7 .", "When the rider is riding the conveyance and exerting a downward force on the platform, the axle can be held in its vertical location relative to the foot support platform 32 and the axle bearing surface 38 by the balance of forces;", "since the ground exerts an upward force on the axle through the wheels.", "In some embodiments it can also desirable to provide a means of retaining the axle in position relative to the inclined axle bearing surface 38 if the rider picks the conveyance off the ground.", "For example, in FIG. 3 , a rod 45 has been inserted in a hole drilled in the pivot member 40 .", "This rod 45 wraps underneath the axle 36 , and can, for example, hold the axle securely against the inclined axle bearing surface 38 or otherwise prevent the axle from falling off.", "In another example, as shown in FIG. 16 , a pin 94 passes through the axle 36 and a slot or hole 91 in the axle bearing surface 38 .", "Preferably, the slot will allow sufficient travel for the axle to move and turn in response to the efforts made by a rider to turn.", "A retention means could also be built into the compression springs 44 R and 44 L by having a protuberance in the springs hook around the underside of the axle.", "Alternatively, a band of the material of which the unitary platform 32 is constructed (not depicted) passing underneath the axle may be molded as an integral part of the unitary platform.", "It should be noted that the various retention devices shown can be used with the various pivot members and axle bearing surfaces described herein.", "In some embodiments, the axle 36 can be a solid or unitary cylinder.", "In some embodiments, the axle 36 can be non-solid, multi-piece, or a shape other than a cylinder.", "The axle can have any other cross-sectional shape, including square, rectangular, variable, etc.", ", and the axle can be hollow, multi-part, a single piece, etc.", "In some embodiments, the axle can have one or more holes, cavities, indentations, extensions, protrusions or other shape features, such as for receiving a spring, a pin, an axle retention device, etc.", "or for other purpose, such as to contact a bearing surface or a pivot member.", "In some embodiments, a second material, such as a polymer or aluminum composition can be molded over the axle to form an axle block 92 in the region between the wheels 34 R and 34 L. Alternatively, the axle block may be a formed from a single material, with cylindrical axle segments formed from a second material or the same material protruding from either end.", "In either case, the axle block 92 could include a flat plane to sit flush on the inclined axle bearing surface 38 , or another shaped surface that can interface with a similar or matched surface of the axle bearing surface 38 , which in some embodiments can reduce wear on these surfaces.", "In some embodiments various features needed to retain the axle 36 and wheels laterally and vertically could be readily molded into the axle block.", "For example, a central locating pin transverse to the axle, or locating washers 64 L (and 64 R, not depicted) may be molded as part of the axle block.", "In some embodiments, the axle could be fitted with bearings or bushings near the wheels so that said bearings or bushings provide rolling contact with the inclined axle bearing surface 38 , in order to, for example, modify the steering response or reduce the wear and, friction associated with sliding of the axle 38 on the inclined axle bearing surface 38 .", "In some embodiments, sliding contact can be reduced or eliminated.", "Bearings can be used to support the axle at a more central position, or only at a position just inside the wheels, or additional bearings or wider or multi-race bearings can be use to provide support along more of the axle's width.", "In FIG. 15 , an overmolded axle block 92 is depicted.", "In some embodiments, this can be a simple rectangular prism used in conjunction with the springs and/or pivots described previously, or may incorporate an extended pivot member section as illustrated, including optional curved and non-curved portions.", "In some embodiments, a narrow surface similar to a pivot member 40 can be incorporated into an axle block or a broad surface similar to an extended pivot member 80 or a curved extended pivot member 90 .", "The axle block 92 can be integral to the axle, or assembled to the axle.", "In some embodiments, a substantial portion of a conveyance can be molded out of a plastic material or a thermoplastic fiber reinforced thermoplastic composite as a single piece or as a small number of pieces for assembly, such as, the foot support platform 32 , the rear fender 48 , the inclined axle bearing surface 38 , the pivot member 4 G, any special means for retaining the compression springs 44 L and 44 R, the deadman's brake 60 , and other features could all be molded in a single injection molding operation.", "In some embodiments, all or a portion of the parts can be produced separately.", "In some embodiments, some of these parts can be left out, for example the rear fender 48 , the deadman's brake 60 , or other features or combinations of features as desired.", "Such molding can result in reduces cost and/or reduced weight of the conveyance.", "In some embodiments, features can be designed to simultaneously increase the stiffness and strength of the conveyance, while reducing the cost and amount of material, used.", "In FIG. 5 , examples of molded-in cavities 54 are depicted.", "Variations of the design of molded-in cavities are possible, such as are used in the production of various items including those found in the lower leg assembly of a pedestal office chair, where said assembly was molded from a thermoplastic.", "In some embodiments, an extended flanges 56 on the central portion of the platform 32 in FIG. 5 can be incorporated, for example, to increase the bending stiffness of the foot support platform 32 about an-axis parallel to the rear axle.", "In some embodiments, portions of the device can be made from wood, metal, or some other appropriate material having appropriate characteristics of weight, stiffness and durability.", "In some embodiments, all or portions of the device can be machined, such as out of plastic, fiber reinforced plastic, metal, or wood.", "In some embodiments, parts can be cast or stamped out of metal.", "Suitable metal for construction of the device include steels and alloys of steel, nickel and/or chromium containing materials, aluminum, titanium, copper, brass, bronze, etc.", "In some embodiments, a lighter material can be utilized for a portion of the device and a harder or more durable material for another portion.", "Elastomers can be utilized for portions of the device as well.", "In some embodiments, a gravity or centrifugal force can be utilized to provide assistance in recovering the conveyance from a turn.", "A gravity or centrifugal force can be used in conjunction with springs, such as coil, leaf, elastomer, etc, or they can be used without springs.", "The recovery from turning can be induced without springs by, for example, ensuring that as the axle pivoted, the central portion of the foot support platform 32 was forced away from the axle (See FIG. 4 ).", "This case, the central portion of the foot support platform 32 would be forced to increase in altitude as the conveyance was tilted and the axle pivoted.", "(In this document, altitude is defined as the distance from the road surface, or a plane having an analogous relationship to the wheels as a road surface, along an axis normal to the road surface or plane.) The central portion of the foot support platform 32 would normally be at a lower altitude from the road surface or analogous plane, and its altitude would increase if the axle pivoted in either direction.", "A similar position restoring force can be provided by the centrifugal force experienced while turning the conveyance.", "This linkage between the pivoting action, and an altitude increase of the foot support platform is referred herein as a “gravity spring”, regardless of how it is accomplished.", "A gravity spring provides a restorative force to return the axle to its normal position substantially perpendicular to the centerline of the skateboard, and the skateboard travels in a substantially straight line unless the rider applies a torque about the centerline by leaning.", "Benefits with a gravity spring can include in some embodiments self-adjustment of a turn restorative force to the weight of a rider or load, reduced number of parts for construction of the conveyance, and elimination of parts subject to breakage or wear and requiring repair or replacement.", "First, the turn restorative force tending to return the front axle to its normal position relative to the long axis of the conveyance 82 with a gravity spring can be related to the weight of the user, potentially rendering one set of parts suitable for riders having a range of weights.", "Second, the need for springs is eliminated, reducing the number of parts used in manufacturing and assembling the conveyance, and eliminating springs or bushings that can break or wear out.", "In one embodiment, a gravity spring is made by using an elongated pivot member 80 or 90 rather than a single pivot point, as depicted in FIGS. 11 , 12 , 14 , 16 , 17 , 18 A and 18 B. In this method, the inclined axle bearing surface 38 can be planar, as in previously described embodiments, or otherwise, and the pivot member 80 or 90 is shaped so that as a compressive force is applied between the axle bearing surface 38 and the axle 36 , such as when the rider leans or shifts his weight, the pivot point (or point of contact between the axle 38 and the pivot member 80 or 90 ) shifts towards the wheel closest to the compressive force.", "This shift causes the axle to rotate in a plane parallel to the travel surface (i.e. turn).", "In some embodiments, the rotation of the axle can cause a turn in the direction of the lean or shift in weight as depicted in FIG. 12 .", "Since the pivot point is closer to the inside wheel (for this discussion, a system of lean left/turn left is assumed, but in some other embodiments, as with other parts of this description, this assumption can be reversed, as understood by one having skill in the art), as the axle 36 pivots, the rearward motion of the inside wheel is less than the forward motion of the outside wheel.", "Since the axle 36 is in contact with the inclined axle bearing surface 38 , the inside wheel moves towards the top surface 51 of the foot support platform 32 by an amount less than the distance that the outside wheel moves away from the top surface 51 of the-foot support platform 32 .", "The net result is that the distance between the central portion of the axle 36 and the nearest point on the top surface of the foot support platform 51 is increased when the axle 36 pivots, elevating the foot support platform and the rider.", "The center of the axle in the gravity spring, shifts down the axle bearing plane, moving it farther away from the top surface of the board, increasing the altitude of the deck, and providing a restorative force.", "The rider or load is closest to the road when the front axle 36 is perpendicular to the long axis of the conveyance 82 , and at least a portion of his foot or the load is elevated whenever the conveyance tilts and the axle pivots in either direction.", "This contributes to the desired gravity spring effect that induces the conveyance to level out so that it travels in a substantially straight line unless the rider supplies a torque around the long axis 82 of the conveyance.", "The magnitude of the centering force imposed by the gravity spring can depend on the width and shape of the pivot member, the angle of the inclined axle bearing surface, as well as other factors.", "For simplicity, a simple rectangular extended pivot member 80 is shown in FIGS. 11-12 , but this block could be rounded off, as long as pivoting of the axle 36 away from its position perpendicular to the long axis of the conveyance 82 produces a shift in the central portion of the foot support platform 32 away from the axle 36 .", "A suitable curved extended pivot member is depicted in FIG. 14 .", "Additional embodiments of curved extended pivot members are provided in FIGS. 16 , 17 , 18 A and 18 B. In some embodiments, an extended pivot member 80 or 90 can be attached to the axle 36 instead of molding it as part of, or fixing it rigidly to, a stationary part such as a portion of the foot support platform 32 or the spring bearing surface 39 .", "In some such embodiments, the spring bearing surface 39 or other portion that the axle block 92 interfaces with could he planar, and an axle block could be overmolded on the axle as described previously.", "The extended pivot member could be molded into the central region of the axle block 92 , and bear against the spring bearing surface 39 .", "Such an arrangement is depicted in FIG. 15 .", "Another embodiment of a gravity spring includes constructing the inclined axle bearing surface 38 to have a non-planar bearing surface as depicted in FIG. 13 .", "In this embodiment, the inclined axle bearing surface is curved or segmented ( 88 A and 88 B), and the slope of the rear part of the surface 88 B is less than the slope of the front part of the surface 88 A, where the slope is measured by the angle between the plane and the top surface 51 of the foot support platform 32 , however in some embodiments, the slopes of these two portions can be reversed, with the slope of the rear part of the surface 88 B being greater than the slope of the front part of the surface 88 A. In addition, other embodiments can have a greater number of differently sloped surfaces on the inclined axle bearing surface 38 , or a curved surface or a variably curved surface where the radius of curvature changes along the surface.", "As the axle is induced to pivot by tilting the platform about its long axis 82 , the inside wheel moves closer to the top surface 51 of the foot support platform 32 along the lesser slope of the rear part of the inclined axle bearing surface 88 B. (Here the terms “inside”", "and “outside”", "refer to the conventional definitions of the inside and outside of the turn.) Meanwhile the outside wheel moves farther from the top-surface 51 of the foot-support platform 32 along the greater slope of the forward part of the inclined axle bearing surface 88 A. Because of this, the outside wheel moves away from the top surface 51 by more than the inside wheel moves towards said top surface 51 , and the altitude of the center of the top surface 51 of the foot support platform increases.", "The inclined axle bearing surface can frequently be shaped so that the altitude of the center of the top surface of the foot support platform is lowest when the axle 36 is perpendicular to the long axis of the conveyance 82 or the altitude of the center of mass of the foot support platform 32 is lowest when the axle 36 is in its normal position, not influenced by an induced tilt of the foot support platform 32 .", "This creates a gravity-spring that causes the conveyance-to travel in a substantially straight line (or the conveyance's normal direction of travel) if it is not deliberately tilted around its long axis 82 through the application of torque by the rider.", "In some embodiments, the inclined axle bearing surface 88 can have a complex curvature designed to facilitate keeping most of the axle in contact with the inclined axle bearing surface 88 , regardless of the degree of pivot, which can have a larger slope towards the front of the conveyance, and a lesser slope towards the rear with a gravity spring unit mounted in the front portion of the conveyance and a larger slope towards the rear of the conveyance and a lesser slope towards the front with a gravity spring unit mounted in the rear portion of the conveyance.", "In some embodiments, a gravity-spring unit can be combined with a set of compression springs 44 R and 44 to create a combined force to restore the conveyance to substantially straight fine motion (or other normal travel direction as designed into the unit).", "The foregoing description of the preferred embodiments of the invention has been presented to illustrate the principles of the invention and not to limit the invention to the particular embodiment illustrated.", "It is intended that the scope of the invention be defined by all of the embodiments encompassed within the following claims and their equivalents.", "All references cited herein, including but not limited to published and unpublished applications, patents, and literature references, and also including but not limited to the references listed in the Appendix, are incorporated herein by reference in their entirety and are hereby made a part of this specification.", "To the extent publications and patents or patent applications incorporated by reference contradict the disclosure contained in the specification, the specification is intended to supersede and/or take precedence over any such contradictory material.", "The term “comprising”", "as used herein is synonymous with “including,” “containing,” or “characterized by,” and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps.", "All numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification are to be understood as being modified in all instances by the term “about.”", "Accordingly, unless indicated to the contrary, the numerical parameters set forth herein are approximations that may vary depending upon the desired properties sought to be obtained.", "At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of any claims in any application claiming priority to the present application, each numerical parameter should be construed in light of the number of significant digits and ordinary rounding approaches.", "The above description discloses several methods and materials of the present invention.", "This invention is susceptible to modifications in the methods and materials, as well as alterations in the fabrication methods and equipment.", "Such modifications will become apparent to those skilled in the art from a consideration of this disclosure or practice of the invention disclosed herein.", "Consequently, it is not intended that this invention be limited to the specific embodiments disclosed herein, but that it cover all modifications and alternatives coming within the true scope and spirit of the invention." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Continuation application of U.S. application Ser. No. 10/832,768, filed Apr. 27, 2004, which is a continuation of U.S. application Ser. No. 09/954,364, filed Sep. 17, 2001, issued as U.S. Pat. No. 6,746,479, which is a Continuation of U.S. application Ser. No. 09/389,832, filed Sep. 3, 1999, issued as U.S. Pat. No. 6,334,870, which is a continuation of U.S. application Ser. No. 08/846,164, filed Apr. 25, 1997, issued as U.S. Pat. No. 6,033,433, the contents of which are hereby incorporated by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to stents of improved configuration which incorporate spiral articulations which unwind to form bracing structures or scaffolding upon expansion. 2. Brief Description of the Prior Art Stents are radially expandable endoprosthesis which are typically intravascular implants capable of being implanted transluminally and enlarged radially after being introduced percutaneously. They have also been implanted in urinary tracts and bile ducts. They are used to reinforce body vessels and to prevent restenosis following angioplasty in the vascular system. They may be self-expanding or expanded by an internal radial force, such as when mounted on a balloon. In the past, stents have assumed many configurations and been made of many materials, including metals and plastic. Ordinary metals such as stainless steel have been used as have shape memory metals such as nitinol and the like. Stents have also been made of biodegradable plastic materials. They have been formed from wire, tube stock, etc. SUMMARY OF THE INVENTION This invention provides a new configuration for stents which may be adapted by all of the various types of prior art stents referred to hereinabove. There are numerous advantages to the new configuration. It limits recoil and adds resistance to compression for the expanded stent, among other things. It is longitudinally flexible in both the unexpanded and expanded conditions. It has several embodiments. An important part of the new configuration includes a spiral or spiral-like structure comprised of joined elements which are coiled or bent and which unwind, uncoil or unbend to a more or less straightened condition on expansion of the stent. Such structures are hereinafter referred to collectively as spirals, spirals or spiral-like structures. These structures provide regions of low strain in the stent during expansion. These elements may be joined to each other or to any radially expansive members of any kind, annular serpentine members being preferred. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a flat view of one pattern embodiment of a stent configuration of the invention (unexpanded); FIG. 2 is a detail of a portion of FIG. 1 ; FIG. 3 is an end view of a stent of the FIG. 1 pattern according to the invention showing it in tubular configuration; FIG. 4 is a showing of a stent in the embodiment of the preceding Figures in perspective and in an unexpanded configuration; FIG. 5 is a showing of the stent of FIG. 4 fully expanded with details of the front and rear of the stent; FIGS. 6 , 7 and 8 are showings of the stent of FIG. 4 in various stages of expansion with only details of the front of the stent shown for simplicity; FIG. 9 is a plan view showing another embodiment of the invention; FIG. 10 is a showing of a modified embodiment; FIG. 11 is a showing of another embodiment; FIG. 12 is a detail of a portion of FIG. 11 ; FIG. 13 is a showing of the stent of FIGS. 11 and 12 in an expanded configuration; FIG. 14 is a showing of another embodiment; FIG. 15 is a showing of still another embodiment; FIG. 16 is a showing of yet another embodiment; FIG. 17 is a showing of still another embodiment; FIGS. 18-28 show various spiral-like arrangements of the invention; FIG. 29 shows another embodiment of the invention; FIG. 30 shows yet another embodiment; and FIG. 31 shows still another embodiment of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One preferred embodiment of the invention is illustrated in FIGS. 1-8 . It comprises a metal tube-like structure 10 as best shown in FIGS. 3 and 4 , such as nitinol or stainless steel, which has been etched or laser cut to the configuration shown in the plan view of FIGS. 1 and 2 and in a short version as shown in FIG. 4 . The configuration is made up of a series of serpentine annular expandable elements or segments 12 which form loops 14 to allow for radial annular expansion. Segments 12 may be other configurations but serpentine is preferred. Elements 12 are interconnected by pairs of elongated members 13 a and 13 b which are attached at one end to successive loops 14 of a segment 12 and which are joined at their other ends to adjacent pairs of elongated members 13 a and 13 b , as best seen in detail in FIG. 2 . Members 13 a and 13 b are preferably of narrower gauge than members 12 and are joined together in a coiled or spiral arrangement as shown generally at 16 . Spiral 16 forms a structure about which members 13 may uncoil or unwind in a counterclockwise direction or clockwise direction to a substantially straight condition, depending on the spiral winding direction, upon radial expansion of members 12 . In this embodiment spirals 16 are formed in alternate wound structures so that some unwind in one direction and some in the other direction. Of course, in any embodiment the spirals can be formed so that they all unwind in one direction, either clockwise or counterclockwise and they may have more or fewer members 13 . Also, more or less spirals may be included between the segments. The unwinding is accompanied by a straightening action with respect to members 13 as is described in more detail in connection with FIGS. 4-8 . It can be seen from FIGS. 4 through 8 that the resultant configuration in an expanded stent of this configuration is comprised of a plurality of cells, the perimeter of each of which is defined by a pair of members or struts defined by the loop portion 14 of segment 12 and a pair of members or struts 13 . The cells are joined at 16 as best seen in FIG. 8 . More specifically the cells are of two kinds as shown in FIG. 8 . A first pair of cells are A and B made up of a segment 12 and two struts 13 a for cell A or 13 b for cell B. A second pair of cells are C and D made up of an inward loop portion 14 of segment 12 and a strut 13 a and a strut 13 b for cells C and D. When a stent of the invention, such as that shown in FIGS. 1-4 undergoes expansion, such as from the embodiment of FIG. 4 , it will appear as shown in FIG. 5 in the fully expanded condition. FIG. 5 shows the stent in perspective. The unwinding action which the coil elements 16 undergo upon stent expansion is best seen in FIGS. 6-8 which show only the front side surface of the stent for simplicity and clarity. As radial expansion begins (seen in FIG. 6 ) it can be appreciated that the spiral elements 16 undergo an unwinding or straightening action by a pulling force on all of the members 13 . Specifically, as expansion occurs, elements 13 undergo a straightening action as can be seen in the early stages of expansion in FIG. 6 . Upon further expansion (seen in FIG. 7 ), spirals 16 undergo further unwinding, i.e., elements 13 undergo further straightening. Finally in FIG. 8 , substantial full expansion provides substantially straightened elements 13 which in that condition limit stent recoil and increase the resistance to compression of the stent. FIG. 9 shows a modified embodiment in which elements 13 a and 13 b contact segment 12 at the end of its loops 14 . Also note in this embodiment that the spirals 16 are all wound in the same direction. FIG. 10 shows an embodiment of the invention in which the spiral members 13 are more bent and less curvilinear but still form a spiral-like configuration 16 . The remainder of the configuration is similar to that of FIG. 9 . In FIG. 10 , elongate members 13 are shown prior to expansion of the stent. When the stent is expanded, members 13 unwind counter-clockwise and straighten somewhat. At full expansion members 13 straighten still further and straighten substantially so as to provide resistance to compression of the stent and low recoil. The expanded configuration displays a cell configuration similar to that seen in FIG. 8 . Other embodiments are shown in subsequent Figures with different spiral arrangements. For example, the embodiment of FIGS. 11-13 shows coiled arrangements 16 which are wound in the same direction and elements 13 attached at the end of loops 14 while some adjacent spirals between segments are interconnected by members 15 . FIG. 14 shows some elements 13 in a spiral 16 contacting the end of loops 14 and some contacting segment 12 proper. Also, some adjacent spirals are interconnected by members 17 . FIG. 15 shows a flattened or elongated spiral arrangement 16 and elements 12 are angled with respect to the longitudinal axis of the stent. In previous embodiments, these elements or segments have been arranged parallel to the axis or horizontal. Elongated spirals as in FIG. 13 and spirals of previous Figures may be mixed together. (Not shown). In the embodiments already discussed, annular expandable segments such as segments 12 are interspersed with spiral arrangements 16 . However, as can be seen in FIG. 16 , at least a substantial portion or all of the stent body can be merely comprised of spiral arrangements 16 connected to each other. Actually, all of the body may consist of spirals. In this embodiment, the elements 13 interconnect between spirals over substantially the entire body of the stent. Optionally, the ends may include segments 12 as shown. The embodiment shown in FIG. 17 shows segments 12 alternately angled in opposite directions and with legs thereof of different length and elements 13 contacting the segments at different locations, i.e., as at the loop portion 14 and at the segment portion proper. FIGS. 18-28 demonstrate examples of what is meant by the terms spiral and spiral-like herein. Of course, additional members may be included in the spirals. FIG. 29 shows segments 12 in a configuration other than the annular serpentine configuration of previous Figures. FIG. 30 shows alternate segments 12 in serpentine annular configuration interconnected by double rows of interconnected coil configurations 16 . FIG. 31 is included to demonstrate that spirals 16 may be included on the ends of a stent 10 . While this invention may be embodied in many different forms, there are described in detail herein specific preferred embodiments of the invention. This description is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated. The above Examples and disclosure are intended to be illustrative and not exhaustive. These examples and description will suggest many variations and alternatives to one of ordinary skill in this art. All these alternatives and variations are intended to be included within the scope of the attached claims. Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the claims attached hereto.
The invention is directed to an expandable stent which is longitudinally flexible in both the unexpanded and expanded conditions. The stent includes spiral structures which at least partially unwind upon expansion of the stent to limit stent recoil. Regions of low strain in the stent during expansion are provided by the spiral structures.
Identify and summarize the most critical features from the given passage.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Continuation application of U.S. application Ser.", "No. 10/832,768, filed Apr. 27, 2004, which is a continuation of U.S. application Ser.", "No. 09/954,364, filed Sep. 17, 2001, issued as U.S. Pat. No. 6,746,479, which is a Continuation of U.S. application Ser.", "No. 09/389,832, filed Sep. 3, 1999, issued as U.S. Pat. No. 6,334,870, which is a continuation of U.S. application Ser.", "No. 08/846,164, filed Apr. 25, 1997, issued as U.S. Pat. No. 6,033,433, the contents of which are hereby incorporated by reference.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention This invention relates to stents of improved configuration which incorporate spiral articulations which unwind to form bracing structures or scaffolding upon expansion.", "Brief Description of the Prior Art Stents are radially expandable endoprosthesis which are typically intravascular implants capable of being implanted transluminally and enlarged radially after being introduced percutaneously.", "They have also been implanted in urinary tracts and bile ducts.", "They are used to reinforce body vessels and to prevent restenosis following angioplasty in the vascular system.", "They may be self-expanding or expanded by an internal radial force, such as when mounted on a balloon.", "In the past, stents have assumed many configurations and been made of many materials, including metals and plastic.", "Ordinary metals such as stainless steel have been used as have shape memory metals such as nitinol and the like.", "Stents have also been made of biodegradable plastic materials.", "They have been formed from wire, tube stock, etc.", "SUMMARY OF THE INVENTION This invention provides a new configuration for stents which may be adapted by all of the various types of prior art stents referred to hereinabove.", "There are numerous advantages to the new configuration.", "It limits recoil and adds resistance to compression for the expanded stent, among other things.", "It is longitudinally flexible in both the unexpanded and expanded conditions.", "It has several embodiments.", "An important part of the new configuration includes a spiral or spiral-like structure comprised of joined elements which are coiled or bent and which unwind, uncoil or unbend to a more or less straightened condition on expansion of the stent.", "Such structures are hereinafter referred to collectively as spirals, spirals or spiral-like structures.", "These structures provide regions of low strain in the stent during expansion.", "These elements may be joined to each other or to any radially expansive members of any kind, annular serpentine members being preferred.", "BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a flat view of one pattern embodiment of a stent configuration of the invention (unexpanded);", "FIG. 2 is a detail of a portion of FIG. 1 ;", "FIG. 3 is an end view of a stent of the FIG. 1 pattern according to the invention showing it in tubular configuration;", "FIG. 4 is a showing of a stent in the embodiment of the preceding Figures in perspective and in an unexpanded configuration;", "FIG. 5 is a showing of the stent of FIG. 4 fully expanded with details of the front and rear of the stent;", "FIGS. 6 , 7 and 8 are showings of the stent of FIG. 4 in various stages of expansion with only details of the front of the stent shown for simplicity;", "FIG. 9 is a plan view showing another embodiment of the invention;", "FIG. 10 is a showing of a modified embodiment;", "FIG. 11 is a showing of another embodiment;", "FIG. 12 is a detail of a portion of FIG. 11 ;", "FIG. 13 is a showing of the stent of FIGS. 11 and 12 in an expanded configuration;", "FIG. 14 is a showing of another embodiment;", "FIG. 15 is a showing of still another embodiment;", "FIG. 16 is a showing of yet another embodiment;", "FIG. 17 is a showing of still another embodiment;", "FIGS. 18-28 show various spiral-like arrangements of the invention;", "FIG. 29 shows another embodiment of the invention;", "FIG. 30 shows yet another embodiment;", "and FIG. 31 shows still another embodiment of the invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One preferred embodiment of the invention is illustrated in FIGS. 1-8 .", "It comprises a metal tube-like structure 10 as best shown in FIGS. 3 and 4 , such as nitinol or stainless steel, which has been etched or laser cut to the configuration shown in the plan view of FIGS. 1 and 2 and in a short version as shown in FIG. 4 .", "The configuration is made up of a series of serpentine annular expandable elements or segments 12 which form loops 14 to allow for radial annular expansion.", "Segments 12 may be other configurations but serpentine is preferred.", "Elements 12 are interconnected by pairs of elongated members 13 a and 13 b which are attached at one end to successive loops 14 of a segment 12 and which are joined at their other ends to adjacent pairs of elongated members 13 a and 13 b , as best seen in detail in FIG. 2 .", "Members 13 a and 13 b are preferably of narrower gauge than members 12 and are joined together in a coiled or spiral arrangement as shown generally at 16 .", "Spiral 16 forms a structure about which members 13 may uncoil or unwind in a counterclockwise direction or clockwise direction to a substantially straight condition, depending on the spiral winding direction, upon radial expansion of members 12 .", "In this embodiment spirals 16 are formed in alternate wound structures so that some unwind in one direction and some in the other direction.", "Of course, in any embodiment the spirals can be formed so that they all unwind in one direction, either clockwise or counterclockwise and they may have more or fewer members 13 .", "Also, more or less spirals may be included between the segments.", "The unwinding is accompanied by a straightening action with respect to members 13 as is described in more detail in connection with FIGS. 4-8 .", "It can be seen from FIGS. 4 through 8 that the resultant configuration in an expanded stent of this configuration is comprised of a plurality of cells, the perimeter of each of which is defined by a pair of members or struts defined by the loop portion 14 of segment 12 and a pair of members or struts 13 .", "The cells are joined at 16 as best seen in FIG. 8 .", "More specifically the cells are of two kinds as shown in FIG. 8 .", "A first pair of cells are A and B made up of a segment 12 and two struts 13 a for cell A or 13 b for cell B. A second pair of cells are C and D made up of an inward loop portion 14 of segment 12 and a strut 13 a and a strut 13 b for cells C and D. When a stent of the invention, such as that shown in FIGS. 1-4 undergoes expansion, such as from the embodiment of FIG. 4 , it will appear as shown in FIG. 5 in the fully expanded condition.", "FIG. 5 shows the stent in perspective.", "The unwinding action which the coil elements 16 undergo upon stent expansion is best seen in FIGS. 6-8 which show only the front side surface of the stent for simplicity and clarity.", "As radial expansion begins (seen in FIG. 6 ) it can be appreciated that the spiral elements 16 undergo an unwinding or straightening action by a pulling force on all of the members 13 .", "Specifically, as expansion occurs, elements 13 undergo a straightening action as can be seen in the early stages of expansion in FIG. 6 .", "Upon further expansion (seen in FIG. 7 ), spirals 16 undergo further unwinding, i.e., elements 13 undergo further straightening.", "Finally in FIG. 8 , substantial full expansion provides substantially straightened elements 13 which in that condition limit stent recoil and increase the resistance to compression of the stent.", "FIG. 9 shows a modified embodiment in which elements 13 a and 13 b contact segment 12 at the end of its loops 14 .", "Also note in this embodiment that the spirals 16 are all wound in the same direction.", "FIG. 10 shows an embodiment of the invention in which the spiral members 13 are more bent and less curvilinear but still form a spiral-like configuration 16 .", "The remainder of the configuration is similar to that of FIG. 9 .", "In FIG. 10 , elongate members 13 are shown prior to expansion of the stent.", "When the stent is expanded, members 13 unwind counter-clockwise and straighten somewhat.", "At full expansion members 13 straighten still further and straighten substantially so as to provide resistance to compression of the stent and low recoil.", "The expanded configuration displays a cell configuration similar to that seen in FIG. 8 .", "Other embodiments are shown in subsequent Figures with different spiral arrangements.", "For example, the embodiment of FIGS. 11-13 shows coiled arrangements 16 which are wound in the same direction and elements 13 attached at the end of loops 14 while some adjacent spirals between segments are interconnected by members 15 .", "FIG. 14 shows some elements 13 in a spiral 16 contacting the end of loops 14 and some contacting segment 12 proper.", "Also, some adjacent spirals are interconnected by members 17 .", "FIG. 15 shows a flattened or elongated spiral arrangement 16 and elements 12 are angled with respect to the longitudinal axis of the stent.", "In previous embodiments, these elements or segments have been arranged parallel to the axis or horizontal.", "Elongated spirals as in FIG. 13 and spirals of previous Figures may be mixed together.", "(Not shown).", "In the embodiments already discussed, annular expandable segments such as segments 12 are interspersed with spiral arrangements 16 .", "However, as can be seen in FIG. 16 , at least a substantial portion or all of the stent body can be merely comprised of spiral arrangements 16 connected to each other.", "Actually, all of the body may consist of spirals.", "In this embodiment, the elements 13 interconnect between spirals over substantially the entire body of the stent.", "Optionally, the ends may include segments 12 as shown.", "The embodiment shown in FIG. 17 shows segments 12 alternately angled in opposite directions and with legs thereof of different length and elements 13 contacting the segments at different locations, i.e., as at the loop portion 14 and at the segment portion proper.", "FIGS. 18-28 demonstrate examples of what is meant by the terms spiral and spiral-like herein.", "Of course, additional members may be included in the spirals.", "FIG. 29 shows segments 12 in a configuration other than the annular serpentine configuration of previous Figures.", "FIG. 30 shows alternate segments 12 in serpentine annular configuration interconnected by double rows of interconnected coil configurations 16 .", "FIG. 31 is included to demonstrate that spirals 16 may be included on the ends of a stent 10 .", "While this invention may be embodied in many different forms, there are described in detail herein specific preferred embodiments of the invention.", "This description is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated.", "The above Examples and disclosure are intended to be illustrative and not exhaustive.", "These examples and description will suggest many variations and alternatives to one of ordinary skill in this art.", "All these alternatives and variations are intended to be included within the scope of the attached claims.", "Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the claims attached hereto." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation under 35 USC §120 of U.S. application Ser. No. 10/662,989 filed Sep. 15, 2003 now U.S. Pat. No. 7,422,008 (the “second application”), which is itself a continuation under 35 USC §120 of U.S. application Ser. No. 10/646,358 filed Aug. 22, 2003 now abandoned (the “first application”). The entireties of these prior applications are incorporated by reference herein. This application is also related to U.S. application Ser. No. 10/793,131 filed Mar. 4, 2004 (now U.S. Pat. No. 7,320,318, issued Jan. 22, 2008), which is itself a continuation-in-part under 35 USC §120 of the aforementioned second application (U.S. application Ser. No. 10/662,989 filed Sep. 15, 2003). BACKGROUND OF THE INVENTION The invention is generally related to bow string releases and is specifically directed to a strap for a release. Bow string releases are well known in the industry. Typically, a bow string release is designed to engage and lock a bow string in a mechanical sear for allowing the archer to pull the bow to its maximum draw. A trigger mechanism is then used to unlock the sear mechanism and release the string to fire the arrow. As is typical, most bow string releases are secured to the wrist of the archer, permitting the release to be held in an at ready position while freeing the fingers of the hand for other tasks. Also, by attaching the release to the archer at the wrist area, the amount of strain on the hand is greatly decreased when high draw weight bows are utilized, which is typical in archery hunting and archery tournaments. Many various straps and harnesses are available for bow string releases. An example of a widely accepted V-type strap is shown in U.S. Pat. No. 4,831,997 entitled: Wrist Strap, issued to Greene, on May 23, 1989. The strap has two ends that are placed around the wrist and then attached to secure the release strap and release to the wrist of the archer. One mechanism to couple the strap about the archer's wrist is to provide a receiver on a first end of the strap. The archer then must manipulate the second end of the strap through the receiver, and then place a pin on the receiver through a hole provided on the second end of the strap, similar to operation of a belt worn around a waist. Many currently available straps for bow string releases are difficult for the archer to couple about their wrist. This is because the strap remains proximal to the archer's shooting hand, preventing the archer from using their shooting hand to assist the archer's off-hand in manipulating the strap. It has proven difficult for archers to one-handedly manipulate the second end of the strap through the receiver, and then place the pin on the receiver through the hole provided on the second end of the strap. Additionally, repeated placement of the pin on the receiver through the hole provided on the second end of the strap causes the hole to stretch during repeated drawing of the bow during use. This stretch causes the hole on the second end of the strap to disadvantageously expand. SUMMARY OF THE INVENTION This invention relates to an improved strap for a bow string release. According to preferred embodiments of the present invention, the strap has two ends, a first end and a second end. The first end of the strap is provided with a receiver for receiving a tab that is coupled with the second end of the strap. Preferably, the tab on the second end of the strap is sized to allow the archer to place the tab of the second end through the receiver of the first end of the strap, and have the tab of the second end selectively remain through the receiver of the first end of the strap. This allows the archer to have the ability to have the second end of the strap already started through the receiver of the first end of the strap, easing the way in which archers couple the strap to their wrist. According to another aspect of the present invention, the strap is constructed in multi-layer fashion, a first padded layer that provides comfortable contact with the archer's skin, among other benefits, and a second non-stretchable layer that provides the strap with a robust design that prevents the strap from stretching, and prevents holes in the strap from expanding through repeated use, among other benefits. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a preferred embodiment of a strap for a bow string release. FIG. 2 is a perspective view of a preferred embodiment of a strap for a bow string release, the strap coupled about an archer's wrist, the strap in an open position. FIG. 3 is a perspective view of a preferred embodiment of a strap for a bow string release, the strap coupled about an archer's wrist, the strap in a semiclosed (or open) position. FIG. 4 is a perspective view of a preferred embodiment of a strap for a bow string release, the strap coupled about an archer's wrist, the strap in a closed position. FIG. 5 is a perspective view of a preferred embodiment of a strap for a bow string release, the strap coupled about an archer's wrist, the strap in a closed position, and a tab of the strap in a restrained position. DESCRIPTION OF THE PREFERRED EMBODIMENT Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention that may be embodied in other specific structure. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims. Referring now to FIG. 1 , a perspective view of a preferred embodiment of a strap 12 for a bow string release 10 is shown. The strap 12 has two ends, a first end 20 and a second end 22 . It is noted that reference to either the first end 20 or the second end 22 refers generally to the last segments of the strap 12 , not to the absolute extremities of the strap 12 . The first end of the strap 12 is provided with a receiver 42 for receiving a tab 30 that is coupled with the second end 22 of the strap 12 . Preferably, the tab on the second end 22 of the strap 12 is sized to allow the archer to place the tab 30 of the second end 22 through the receiver 42 of the first end 20 of the strap 12 , and have the tab 30 of the second end 22 selectively remain through the receiver 42 of the first end 20 of the strap 12 . This allows the archer to have the ability to have the second end 22 of the strap 12 already started through the receiver 42 of the first end 20 of the strap 12 , easing the way in which archers couple the strap 12 to their wrist. It is understood that the first end may refer to either end of the strap, as long as the strap has two ends. It is preferable to shape the tab 30 as a triangle, as shown, in order to ease folding of the tab 30 to fit through the receiver 42 , although other shapes may be readily used. The receiver 42 is coupled with a receiver pin 46 which can be inserted into holes 40 on the strap 12 , belt fashion. The receiver 42 also preferably has a receiver roller 48 to facilitate sliding of the second end of the strap 22 through the receiver 42 . It should be understood that other means for maintaining the second end 22 in a semi-closed position relative to said first end 20 may be used, such as a hook and loop attachment. Still referring to FIG. 1 , but also shown in FIGS. 2-6 , according to another aspect of the present invention, the strap 12 is constructed in multi-layer fashion, a first preferably padded layer 24 that provides 15 comfortable contact with the archer's skin. A second non-stretchable layer 26 prevents the strap 12 from stretching, and also advantageously prevents holes 40 in the strap 12 from expanding through repeated use and placing of a pulling load on the holes 40 by a receiver pin 46 . Preferably, the second layer 26 is formed with a nylon ballistic material. Optionally, a third layer 28 is provided on the outermost portion of the strap 12 , the third layer 28 preferably formed from a material such as leather to give the strap 12 an appealing appearance. Common techniques for fabric coupling include sewing and adhesives, although any suitable coupling mechanism can be used. The shape of the strap 12 is shown in a V-shaped pattern, although the strap 12 can take on other configurations to suit the archer's wrist. Referring now to FIG. 2 , the strap 12 is shown coupled about an archer's wrist, the strap 12 in an open position as shown. In this open position, the second end of the strap 22 has been withdrawn from the receiver 42 by flexing the tab 30 to decrease its effective width from its ordinary strap width 32 , which is preferably greater than the width 44 of the receiver, until the strap width 32 is decreased by folding or otherwise, as shown in FIG. 2 . It is believed that archers will prefer to keep the strap 12 in a semi-open position when the release is not in use, as described with relation to FIG. 1 , in order to avoid having to manipulate the second end 22 of the strap 12 through the receiver 42 . Referring now to FIG. 3 , the strap 12 is shown in a semi-open position. In this position, the archer has initially placed his wrist into the strap 12 , but has not yet coupled the receiver pin 46 into any one of the holes 40 (not visible in FIG. 3 ). Referring now to FIG. 4 , the strap 12 is shown in a closed position. In this position, the archer has initially placed his wrist into the strap 12 , and has now coupled the receiver pin 46 into any one of the holes 40 to secure the strap about the wrist. Referring now to FIG. 5 , the strap 12 is shown coupled about an archer's wrist, the strap in a closed position as described in relation to FIG. 5 , and the tab 30 of the strap 12 in a restrained position. In this restrained condition, a portion of the second end of the strap 22 , preferably the elastic member 36 , has been placed into clip 60 . The first end of the strap 20 has a clip 60 coupled to the strap 12 by a clip receiver strap 62 . The clip receiver strap 62 preferably allows the clip 60 to slide laterally to engage the tab 30 for a wide variety of wrist sizes, and to keep the second end 30 of the strap 22 relatively secured to the strap 12 itself. The clip 60 is also shown in a second position 60 ′ although the clip 60 preferably has the capability to slide along a range of lengths along the receiver strap 62 . The elastic member 36 enables the second end of the strap 22 to be restrained, yet avoids the receiver pin 46 from being inadvertently withdrawn from a hole 40 , as could be possible with an archer having a large wrist size. It is understood that alternative embodiments of the present invention could also be employed to selectively maintain the second end 22 of the strap 12 through first end 20 of the strap, said alternative embodiments not shown in the drawings. This could be accomplished by having a piece of cord fasted to the 10 second end 22 , and then weaving the cord through the receiver. Alternatively, an elastic member could be coupled with the first end 20 , and then coupled with the second end 22 . The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.
A strap for a bow string release is provided to form a semi-closed (or open) hand receiving condition wrist strap for facilitating quick attachment and detachment of the strap to the wrist. The strap facilitates one-handed coupling about an archer's wrist by selectively maintaining the semi-closed (or semi-open) hand receiving condition so that the archer does not have to manually insert a first end of the strap through a second end of the strap.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation under 35 USC §120 of U.S. application Ser.", "No. 10/662,989 filed Sep. 15, 2003 now U.S. Pat. No. 7,422,008 (the “second application”), which is itself a continuation under 35 USC §120 of U.S. application Ser.", "No. 10/646,358 filed Aug. 22, 2003 now abandoned (the “first application”).", "The entireties of these prior applications are incorporated by reference herein.", "This application is also related to U.S. application Ser.", "No. 10/793,131 filed Mar. 4, 2004 (now U.S. Pat. No. 7,320,318, issued Jan. 22, 2008), which is itself a continuation-in-part under 35 USC §120 of the aforementioned second application (U.S. application Ser.", "No. 10/662,989 filed Sep. 15, 2003).", "BACKGROUND OF THE INVENTION The invention is generally related to bow string releases and is specifically directed to a strap for a release.", "Bow string releases are well known in the industry.", "Typically, a bow string release is designed to engage and lock a bow string in a mechanical sear for allowing the archer to pull the bow to its maximum draw.", "A trigger mechanism is then used to unlock the sear mechanism and release the string to fire the arrow.", "As is typical, most bow string releases are secured to the wrist of the archer, permitting the release to be held in an at ready position while freeing the fingers of the hand for other tasks.", "Also, by attaching the release to the archer at the wrist area, the amount of strain on the hand is greatly decreased when high draw weight bows are utilized, which is typical in archery hunting and archery tournaments.", "Many various straps and harnesses are available for bow string releases.", "An example of a widely accepted V-type strap is shown in U.S. Pat. No. 4,831,997 entitled: Wrist Strap, issued to Greene, on May 23, 1989.", "The strap has two ends that are placed around the wrist and then attached to secure the release strap and release to the wrist of the archer.", "One mechanism to couple the strap about the archer's wrist is to provide a receiver on a first end of the strap.", "The archer then must manipulate the second end of the strap through the receiver, and then place a pin on the receiver through a hole provided on the second end of the strap, similar to operation of a belt worn around a waist.", "Many currently available straps for bow string releases are difficult for the archer to couple about their wrist.", "This is because the strap remains proximal to the archer's shooting hand, preventing the archer from using their shooting hand to assist the archer's off-hand in manipulating the strap.", "It has proven difficult for archers to one-handedly manipulate the second end of the strap through the receiver, and then place the pin on the receiver through the hole provided on the second end of the strap.", "Additionally, repeated placement of the pin on the receiver through the hole provided on the second end of the strap causes the hole to stretch during repeated drawing of the bow during use.", "This stretch causes the hole on the second end of the strap to disadvantageously expand.", "SUMMARY OF THE INVENTION This invention relates to an improved strap for a bow string release.", "According to preferred embodiments of the present invention, the strap has two ends, a first end and a second end.", "The first end of the strap is provided with a receiver for receiving a tab that is coupled with the second end of the strap.", "Preferably, the tab on the second end of the strap is sized to allow the archer to place the tab of the second end through the receiver of the first end of the strap, and have the tab of the second end selectively remain through the receiver of the first end of the strap.", "This allows the archer to have the ability to have the second end of the strap already started through the receiver of the first end of the strap, easing the way in which archers couple the strap to their wrist.", "According to another aspect of the present invention, the strap is constructed in multi-layer fashion, a first padded layer that provides comfortable contact with the archer's skin, among other benefits, and a second non-stretchable layer that provides the strap with a robust design that prevents the strap from stretching, and prevents holes in the strap from expanding through repeated use, among other benefits.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a preferred embodiment of a strap for a bow string release.", "FIG. 2 is a perspective view of a preferred embodiment of a strap for a bow string release, the strap coupled about an archer's wrist, the strap in an open position.", "FIG. 3 is a perspective view of a preferred embodiment of a strap for a bow string release, the strap coupled about an archer's wrist, the strap in a semiclosed (or open) position.", "FIG. 4 is a perspective view of a preferred embodiment of a strap for a bow string release, the strap coupled about an archer's wrist, the strap in a closed position.", "FIG. 5 is a perspective view of a preferred embodiment of a strap for a bow string release, the strap coupled about an archer's wrist, the strap in a closed position, and a tab of the strap in a restrained position.", "DESCRIPTION OF THE PREFERRED EMBODIMENT Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention that may be embodied in other specific structure.", "While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.", "Referring now to FIG. 1 , a perspective view of a preferred embodiment of a strap 12 for a bow string release 10 is shown.", "The strap 12 has two ends, a first end 20 and a second end 22 .", "It is noted that reference to either the first end 20 or the second end 22 refers generally to the last segments of the strap 12 , not to the absolute extremities of the strap 12 .", "The first end of the strap 12 is provided with a receiver 42 for receiving a tab 30 that is coupled with the second end 22 of the strap 12 .", "Preferably, the tab on the second end 22 of the strap 12 is sized to allow the archer to place the tab 30 of the second end 22 through the receiver 42 of the first end 20 of the strap 12 , and have the tab 30 of the second end 22 selectively remain through the receiver 42 of the first end 20 of the strap 12 .", "This allows the archer to have the ability to have the second end 22 of the strap 12 already started through the receiver 42 of the first end 20 of the strap 12 , easing the way in which archers couple the strap 12 to their wrist.", "It is understood that the first end may refer to either end of the strap, as long as the strap has two ends.", "It is preferable to shape the tab 30 as a triangle, as shown, in order to ease folding of the tab 30 to fit through the receiver 42 , although other shapes may be readily used.", "The receiver 42 is coupled with a receiver pin 46 which can be inserted into holes 40 on the strap 12 , belt fashion.", "The receiver 42 also preferably has a receiver roller 48 to facilitate sliding of the second end of the strap 22 through the receiver 42 .", "It should be understood that other means for maintaining the second end 22 in a semi-closed position relative to said first end 20 may be used, such as a hook and loop attachment.", "Still referring to FIG. 1 , but also shown in FIGS. 2-6 , according to another aspect of the present invention, the strap 12 is constructed in multi-layer fashion, a first preferably padded layer 24 that provides 15 comfortable contact with the archer's skin.", "A second non-stretchable layer 26 prevents the strap 12 from stretching, and also advantageously prevents holes 40 in the strap 12 from expanding through repeated use and placing of a pulling load on the holes 40 by a receiver pin 46 .", "Preferably, the second layer 26 is formed with a nylon ballistic material.", "Optionally, a third layer 28 is provided on the outermost portion of the strap 12 , the third layer 28 preferably formed from a material such as leather to give the strap 12 an appealing appearance.", "Common techniques for fabric coupling include sewing and adhesives, although any suitable coupling mechanism can be used.", "The shape of the strap 12 is shown in a V-shaped pattern, although the strap 12 can take on other configurations to suit the archer's wrist.", "Referring now to FIG. 2 , the strap 12 is shown coupled about an archer's wrist, the strap 12 in an open position as shown.", "In this open position, the second end of the strap 22 has been withdrawn from the receiver 42 by flexing the tab 30 to decrease its effective width from its ordinary strap width 32 , which is preferably greater than the width 44 of the receiver, until the strap width 32 is decreased by folding or otherwise, as shown in FIG. 2 .", "It is believed that archers will prefer to keep the strap 12 in a semi-open position when the release is not in use, as described with relation to FIG. 1 , in order to avoid having to manipulate the second end 22 of the strap 12 through the receiver 42 .", "Referring now to FIG. 3 , the strap 12 is shown in a semi-open position.", "In this position, the archer has initially placed his wrist into the strap 12 , but has not yet coupled the receiver pin 46 into any one of the holes 40 (not visible in FIG. 3 ).", "Referring now to FIG. 4 , the strap 12 is shown in a closed position.", "In this position, the archer has initially placed his wrist into the strap 12 , and has now coupled the receiver pin 46 into any one of the holes 40 to secure the strap about the wrist.", "Referring now to FIG. 5 , the strap 12 is shown coupled about an archer's wrist, the strap in a closed position as described in relation to FIG. 5 , and the tab 30 of the strap 12 in a restrained position.", "In this restrained condition, a portion of the second end of the strap 22 , preferably the elastic member 36 , has been placed into clip 60 .", "The first end of the strap 20 has a clip 60 coupled to the strap 12 by a clip receiver strap 62 .", "The clip receiver strap 62 preferably allows the clip 60 to slide laterally to engage the tab 30 for a wide variety of wrist sizes, and to keep the second end 30 of the strap 22 relatively secured to the strap 12 itself.", "The clip 60 is also shown in a second position 60 ′ although the clip 60 preferably has the capability to slide along a range of lengths along the receiver strap 62 .", "The elastic member 36 enables the second end of the strap 22 to be restrained, yet avoids the receiver pin 46 from being inadvertently withdrawn from a hole 40 , as could be possible with an archer having a large wrist size.", "It is understood that alternative embodiments of the present invention could also be employed to selectively maintain the second end 22 of the strap 12 through first end 20 of the strap, said alternative embodiments not shown in the drawings.", "This could be accomplished by having a piece of cord fasted to the 10 second end 22 , and then weaving the cord through the receiver.", "Alternatively, an elastic member could be coupled with the first end 20 , and then coupled with the second end 22 .", "The foregoing is considered as illustrative only of the principles of the invention.", "Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described.", "While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims." ]
RELATED APPLICATIONS [0001] This application claims priority to Taiwan Application Serial Number 102105857, filed Feb. 20, 2013, which is herein incorporated by reference. BACKGROUND [0002] 1. Field of Invention [0003] The present invention relates to a light emitting module. More particularly, the present invention relates to a light-emitting module having an optical convergent element. [0004] 2. Description of Related Art [0005] Light sources used in modern lighting devices normally includes incandescent light, halogen light, fluorescent light, cold cathode fluorescent lighting (CCFL), light emitting diode (LED) and so on. Once the light sources have been made, it is hard to modify their color temperature and color rendering. General incandescent light bulbs have good color temperature and color rendering, but suffer a relatively short lifetime and low luminous efficiency. Compare with incandescent lamps, halogen lamps have improved the shortcoming of lifetime and luminous efficiency, but have problems about high heat generation and ultraviolet. In addition, traditional lighting devices with the application of an incandescent principle have limitations of high heat generation, and fixed color temperature and color rendering after they leave the factory. As to the CCFL, it has problems about environment protection because containing mercury, and also has the problems about insufficient color temperature and color rendering. [0006] In recent years, the LED has the predominance of other traditional lighting sources because of its merits of small volume, long lifetime, short reaction time, and the environmental protection without contamination problem about e.g. thermal radiation, mercury and other toxic substance. Two approaches are used in the industry now to emit white LED light, in which one is to combine different wavelength emitting LED chips, and another is using wavelength division converting materials, like semiconductor, phosphor or dye, cooperate with a monochromatic light LED. [0007] However, the emergent LED lighting sources still cannot totally replace traditional lighting sources. The main reason is that the commercialized LED lighting production lacking of the feature to present consistent color temperature accurately, so that inevitably having color temperature differences between the productions. A remote phosphor technique has been provided to solve the non-consistent color temperature problem. However, because the usage of the phosphor in remote phosphor is more than traditional LED, using this technique on fluorescent tube need large area of phosphor, and made high raise in cost inevitably. SUMMARY [0008] In this regard, one embodiment of the present invention provides a light emitting module, so as to mainly apply an optical convergence component to converge the light beams emitted by the light-emitting element in the light emitting module. As such, the required area phosphor is decreased. [0009] To reach the abovementioned purpose, according to one embodiment of the present invention, a light emitting module includes a light-emitting unit, an optical convergent element, and a wave converting element. The light-emitting unit includes a light-emitting element. In which the light-emitting element emits a first light in wavelength λ 1 , and the optical convergent element disposed in a light path of the first light from the light-emitting element, making the first light in wavelength λ 1 converge to a specific area. After passing through the optical convergent element, the first light becomes a second light in wavelength λ 1 of the specific area. The wave converting element is disposed in a light path of the second light from the optical convergent element, and the wave converting element having a wave converting material and an incident plane, making the second light in wavelength λ 1 , after entering the incident plane and the wavelength converting element, be converted to a third light in wavelength λ 2 . [0010] In some embodiments of the present invention, the light-emitting unit also have a reflecting element, surrounding the abovementioned light-emitting unit and directing the first light in the wavelength λ 1 emitted from the light-emitting element to be reflected first by the reflecting element, and then to enter the optical convergent element. [0011] In some embodiments of the present invention, the light emitting module, further including a diffusion element, disposed on the top of the emitting direction of the third light in wavelength λ 2 , to uniformly diffuse and receive the third light in wavelength λ 2 , which passing through the wavelength converting element. [0012] In some embodiments of the present invention, the area of the incident plane for the wavelength converting element, substantially equal to the specific area of the second light in the wavelength λ 1 , which comes from the optical convergent element. [0013] In some embodiments of the present invention, the wavelength converting element includes: a body; and at least one wavelength converting material, which is separated in the body in a uniform or patterned or laminar way. [0014] In some embodiments of the present invention, the wavelength converting material is one selected from the group consisting of phosphor, dye, pigments, quantum dots (QDs) and combinations thereof. [0015] In some embodiments of the present invention, the phosphor is a phosphor that is capable of emitting visible light; and base on one embodiment of the invention, a light color of the visible light emitted from the phosphor is one selected from the group consisting of red, green, blue and combinations thereof. [0016] In some embodiments of the present invention, the light-emitting element is a light emitting diode chip. According to one embodiment of the invention, the light emitting diode chip is an ultraviolet light chip or a blue light chip. [0017] In some embodiments of the present invention, the optical convergent element is a condensing lens. Following one embodiment of the invention, condensing lens can be one selected from the group consisting of a convex lens, spherical lens, hemispherical lens, spherocylinder lens, cylindrical lens, molded lens, Fresnel lens and combinations thereof. And in another embodiment of the invention, the convex lens is selected from the group consisting of plane-convex lens, double-convex lens, concave-convex lens and combinations thereof. [0018] In some embodiments of the present invention, the light emitting module further includes encapsulating glue, covering the abovementioned light-emitting element. [0019] By the abovementioned embodiments of the present invention, the area of the incident plane used on the wavelength converting element for lens can be reduced effectively. In other words, it can save the wavelength converting material effectively. [0020] It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed. BRIEF DESCRIPTION OF THE DRAWINGS [0021] The invention can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows: [0022] FIG. 1 is a schematic diagram of light emitting module; and [0023] FIG. 2 is a schematic diagram of light emitting module; and [0024] FIG. 3 is a schematic diagram of light emitting module; and [0025] FIG. 4A is a schematic diagram of light emitting module using in a strip lamp; and [0026] FIG. 4B is a schematic diagram of light emitting module using in a strip lamp according to one embodiment of this invention. DETAILED DESCRIPTION [0027] Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. [0028] FIG. 1 is a schematic diagram of light emitting module according to one embodiment of this invention. As shown in FIG. 1 , the light emitting module of this embodiment includes a light-emitting unit, an optical convergent element 104 and a wavelength converting element 106 . In which, the light-emitting unit includes a light-emitting element 102 . The light-emitting element 102 emits a first light 103 with wavelength λ 1 , passing through an optical convergent element 104 , which disposed in a light path of the first light 103 from the light-emitting element 102 , making the first light 103 in wavelength λ 1 converge to a specific area, and the first light 104 becomes a second light 105 in wavelength λ 1 . The second light 105 emits from the optical convergent element 104 , irradiating on an incident plane of the wavelength converting element 106 . Having a wavelength converting material in the wavelength converting element 106 makes the second light 105 in wavelength λ 1 , after entering the incident plane and the wavelength converting element 106 , be converted to a third light 107 in wavelength λ 2 . [0029] According to one embodiment of the present invention, the light-emitting element 102 includes a light emitting diode chip, mounted on a substrate 108 . The surface of substrate 108 , which the light emitting diode chip mounted, can coat a retro-reflective material layer on it, or the substrate 108 is made by retro-reflective material. In which, the light emitting diode chip may be an ultraviolet light chip or a blue light chip. [0030] According to one embodiment of the present invention, the area of the incident plane on the wavelength converting element 106 , essentially equal to the specific area of the second light 105 in wavelength λ 1 , which comes from the optical convergent element 104 . [0031] According to one embodiment of the present invention, the wavelength converting element 106 includes a body and at least one wavelength converting material, which is separated in the body in a uniform or graphical or laminar way. [0032] According to one embodiment of the present invention, the light emitting module includes a diffusion element, which is disposed on the top of the emitting direction of the third light 107 in wavelength λ 2 , in order to diffuse, unify and receive the third light 107 in wavelength λ 2 , which passing through the wavelength converting element. [0033] According to one embodiment of the present invention, the optical convergent element 104 is a condensing lens. In some embodiments of the present invention, the condensing lens is selected from the group consisting of a convex lens, spherical lens, hemispherical lens, spherocylinder lens, cylindrical lens, molded lens, Fresnel lens and combinations thereof. In another embodiment, convex lens is selected from the group consisting of plane-convex lens, double-convex lens, concave-convex lens and combinations thereof. [0034] FIG. 2 depicts a schematic diagram of light emitting module according to one embodiment of this invention. As shown in FIG. 2 , the light emitting module in the embodiment includes a light unit, an optical convergence element 204 , a reflecting element 209 and a wavelength converting element 206 . The light unit contains a light-emitting element 202 . The light-emitting element 202 emits a first light 203 in wavelength λ 1 . The first light 203 in wavelength λ 1 is first reflected by the reflecting element 209 , changing the optical pathway, and then passing through the optical convergence element 204 . After passing through the optical convergence element 204 , the first light 203 in wavelength λ 1 is converged to a specific area and becoming a second light 205 in wavelength λ 1 . The second light 205 is first emitted from the optical convergence element 204 , then irradiate on an incident plane of a wavelength converting element 206 , which includes a wavelength converting material, after passing through the wavelength converting element 206 , the second light 205 in wavelength λ 1 is converted to a third light 207 in wavelength λ 2 . [0035] According to one embodiment of the present invention, the light-emitting element 202 includes a light emitting diode chip, mounted on a substrate 208 . The surface of substrate 208 , which the light emitting diode chip mounted, can coat a retro-reflective material layer on it, or the substrate 208 is made by retro-reflective material. [0036] According to one embodiment of the present invention, the area of the incident plane on the wavelength converting element 206 , essentially equal to the specific area of the second light 205 in wavelength λ 1 , which comes from the optical convergent element 204 . [0037] According to one embodiment of the present invention, the wavelength converting element 206 includes a body and at least one wavelength converting material, which is separated in the body in a uniform or graphical or laminar way. [0038] According to one embodiment of the present invention, the light emitting module includes a diffusion element, which is disposed on the top of the emitting direction of the third light 207 in wavelength λ 2 , in order to diffuse, unify and receive the third light 207 in wavelength λ 2 , which passing through the wavelength converting element. [0039] According to one embodiment of the present invention, the optical convergent element 204 is a condensing lens. In some embodiments of the present invention, the condensing lens is selected from the group consisting of a convex lens, spherical lens, hemispherical lens, spherocylinder lens, cylindrical lens, molded lens, Fresnel lens and combinations thereof. In another embodiment, convex lens is selected from the group consisting of plane-convex lens, double-convex lens, concave-convex lens and combinations thereof. [0040] FIG. 3 depicts a schematic drawing of light emitting module according to one embodiment of this invention. As shown in FIG. 3 , the light emitting module in the embodiment includes a light unit, an optical convergence lens array 304 , a reflecting substrate 308 and a wavelength converting element array 306 . In which, the light unit includes a light emitting diode chip array 302 . In one embodiment of the present invention, every light emitting diode chip array 302 includes encapsulating glue covering every light emitting diode chips. Refer to FIG. 1 and FIG. 2 , the light emitting diode chip array 302 emits first light in wavelength λ 1 , then the first light in wavelength λ 1 passing through the optical convergence lens array 304 . The first light is converged to a specific area and becoming a second light in wavelength λ 1 , after passing through the optical convergence lens array 304 . The second light is first emitted from the optical convergence lens array 304 , then irradiate on the incident plane of the wavelength converting element array 306 . [0041] Because the wavelength converting element array 306 includes a wavelength converting material, after entering the incident plane and passing through the wavelength converting element array 306 , the second light in wavelength λ 1 is converted to a third light in wavelength λ 2 . Then, the third light after being received and passing through wavelength converting element array 306 , entering a diffusion element 310 to diffuse and unify the third light. [0042] FIG. 4A and FIG. 4B depict schematic diagrams of light emitting module using in a strip lamp according to one embodiment of this invention. FIG. 4B is a cross-sectional view of strip lamp 400 plane A in FIG. 4A . [0043] As shown in FIG. 4B , the strip lamp 400 includes a light-emitting unit, an optical convergent lens 404 , an optical reflecting element 408 and a strip-shape wavelength converting element 406 . Abovementioned light-emitting unit includes a plurality of light emitting diodes 402 arranged in lines. Refer to FIG. 1 and FIG. 2 , a plurality of light emitting diode chips emit first light, then the first light in wavelength λ 1 passing through the optical convergence lens 404 . The first light is converged to a specific area and becoming a second light in wavelength λ 1 , after passing through the optical convergence lens 404 . The optical convergence lens 404 is on the top of the light emitting diode chips, covering all the irradiation range with the emission angle of the light emitting diode chips 402 . For example, the emission angle of the light emitting diode chip 402 can be 120 degrees, and the optical convergence lens 404 can cover the irradiation range for at least 120 degree for the light emitting diode chip 402 . After that, the second light irradiate on the incident plane of the strip-shape wavelength converting element 406 , after being emitted from the optical convergence lens 404 . [0044] Because the strip-shape wavelength converting element 406 includes a wavelength converting material, after entering the incident plane and passing through the strip-shape wavelength converting element 406 , the second light in wavelength λ 1 is converted to a third light in wavelength λ 2 . Then, the third light after being received and passing through the strip-shape wavelength converting element 406 , entering a diffusion lens 409 to diffuse and unify the third light. [0045] In some embodiments, the light emitting diode chip 402 may be a light emitting diode chip which emits blue or ultraviolet light in wavelength λ 1 . The strip-shape wavelength converting element 406 can contain a wavelength converting material, which convert λ 1 to λ 2 , where λ 2 is larger than λ 1 . To be specific, the light emitting diode chip 402 emits a light having wavelength λ 1 (e.g., short wavelength light like ultraviolet light or blue light), which can excite the wavelength converting element, making the light having wavelength λ 1 (e.g., ultraviolet light or blue light) convert to a light having wavelength λ 2 (e.g., red light, green light or yellow light) after passing through the strip-shape wavelength converting element 406 . [0046] For example, when the light emitting diode chip 402 emits ultraviolet light, the wavelength converting element can emit phosphor, which is selected from the group consisting of red color, green color, blue color, and combinations thereof, to convert the ultraviolet light to the different color emergent light. In one embodiment of the invention, the wavelength converting material is selected from the group consisting of phosphor, dye, pigments, quantum dots (QDs) and combinations thereof. [0047] Although the present invention has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein. [0048] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims.
A light emitting module includes a light-emitting unit, a wavelength converting element and an optical convergent element for partially or totally converting the wavelength of incident light. The light-emitting unit includes a light-emitting element which emits a first light, the wavelength converting element and an optical convergent element disposed in a light path of the first light from the light-emitting element, such that the first light is converted into a particular light at a specific area with a reduced beam diameter after passing through the optical convergent element and before entering the wavelength converting element.
Identify the most important claim in the given context and summarize it
[ "RELATED APPLICATIONS [0001] This application claims priority to Taiwan Application Serial Number 102105857, filed Feb. 20, 2013, which is herein incorporated by reference.", "BACKGROUND [0002] 1.", "Field of Invention [0003] The present invention relates to a light emitting module.", "More particularly, the present invention relates to a light-emitting module having an optical convergent element.", "[0004] 2.", "Description of Related Art [0005] Light sources used in modern lighting devices normally includes incandescent light, halogen light, fluorescent light, cold cathode fluorescent lighting (CCFL), light emitting diode (LED) and so on.", "Once the light sources have been made, it is hard to modify their color temperature and color rendering.", "General incandescent light bulbs have good color temperature and color rendering, but suffer a relatively short lifetime and low luminous efficiency.", "Compare with incandescent lamps, halogen lamps have improved the shortcoming of lifetime and luminous efficiency, but have problems about high heat generation and ultraviolet.", "In addition, traditional lighting devices with the application of an incandescent principle have limitations of high heat generation, and fixed color temperature and color rendering after they leave the factory.", "As to the CCFL, it has problems about environment protection because containing mercury, and also has the problems about insufficient color temperature and color rendering.", "[0006] In recent years, the LED has the predominance of other traditional lighting sources because of its merits of small volume, long lifetime, short reaction time, and the environmental protection without contamination problem about e.g. thermal radiation, mercury and other toxic substance.", "Two approaches are used in the industry now to emit white LED light, in which one is to combine different wavelength emitting LED chips, and another is using wavelength division converting materials, like semiconductor, phosphor or dye, cooperate with a monochromatic light LED.", "[0007] However, the emergent LED lighting sources still cannot totally replace traditional lighting sources.", "The main reason is that the commercialized LED lighting production lacking of the feature to present consistent color temperature accurately, so that inevitably having color temperature differences between the productions.", "A remote phosphor technique has been provided to solve the non-consistent color temperature problem.", "However, because the usage of the phosphor in remote phosphor is more than traditional LED, using this technique on fluorescent tube need large area of phosphor, and made high raise in cost inevitably.", "SUMMARY [0008] In this regard, one embodiment of the present invention provides a light emitting module, so as to mainly apply an optical convergence component to converge the light beams emitted by the light-emitting element in the light emitting module.", "As such, the required area phosphor is decreased.", "[0009] To reach the abovementioned purpose, according to one embodiment of the present invention, a light emitting module includes a light-emitting unit, an optical convergent element, and a wave converting element.", "The light-emitting unit includes a light-emitting element.", "In which the light-emitting element emits a first light in wavelength λ 1 , and the optical convergent element disposed in a light path of the first light from the light-emitting element, making the first light in wavelength λ 1 converge to a specific area.", "After passing through the optical convergent element, the first light becomes a second light in wavelength λ 1 of the specific area.", "The wave converting element is disposed in a light path of the second light from the optical convergent element, and the wave converting element having a wave converting material and an incident plane, making the second light in wavelength λ 1 , after entering the incident plane and the wavelength converting element, be converted to a third light in wavelength λ 2 .", "[0010] In some embodiments of the present invention, the light-emitting unit also have a reflecting element, surrounding the abovementioned light-emitting unit and directing the first light in the wavelength λ 1 emitted from the light-emitting element to be reflected first by the reflecting element, and then to enter the optical convergent element.", "[0011] In some embodiments of the present invention, the light emitting module, further including a diffusion element, disposed on the top of the emitting direction of the third light in wavelength λ 2 , to uniformly diffuse and receive the third light in wavelength λ 2 , which passing through the wavelength converting element.", "[0012] In some embodiments of the present invention, the area of the incident plane for the wavelength converting element, substantially equal to the specific area of the second light in the wavelength λ 1 , which comes from the optical convergent element.", "[0013] In some embodiments of the present invention, the wavelength converting element includes: a body;", "and at least one wavelength converting material, which is separated in the body in a uniform or patterned or laminar way.", "[0014] In some embodiments of the present invention, the wavelength converting material is one selected from the group consisting of phosphor, dye, pigments, quantum dots (QDs) and combinations thereof.", "[0015] In some embodiments of the present invention, the phosphor is a phosphor that is capable of emitting visible light;", "and base on one embodiment of the invention, a light color of the visible light emitted from the phosphor is one selected from the group consisting of red, green, blue and combinations thereof.", "[0016] In some embodiments of the present invention, the light-emitting element is a light emitting diode chip.", "According to one embodiment of the invention, the light emitting diode chip is an ultraviolet light chip or a blue light chip.", "[0017] In some embodiments of the present invention, the optical convergent element is a condensing lens.", "Following one embodiment of the invention, condensing lens can be one selected from the group consisting of a convex lens, spherical lens, hemispherical lens, spherocylinder lens, cylindrical lens, molded lens, Fresnel lens and combinations thereof.", "And in another embodiment of the invention, the convex lens is selected from the group consisting of plane-convex lens, double-convex lens, concave-convex lens and combinations thereof.", "[0018] In some embodiments of the present invention, the light emitting module further includes encapsulating glue, covering the abovementioned light-emitting element.", "[0019] By the abovementioned embodiments of the present invention, the area of the incident plane used on the wavelength converting element for lens can be reduced effectively.", "In other words, it can save the wavelength converting material effectively.", "[0020] It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed.", "BRIEF DESCRIPTION OF THE DRAWINGS [0021] The invention can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows: [0022] FIG. 1 is a schematic diagram of light emitting module;", "and [0023] FIG. 2 is a schematic diagram of light emitting module;", "and [0024] FIG. 3 is a schematic diagram of light emitting module;", "and [0025] FIG. 4A is a schematic diagram of light emitting module using in a strip lamp;", "and [0026] FIG. 4B is a schematic diagram of light emitting module using in a strip lamp according to one embodiment of this invention.", "DETAILED DESCRIPTION [0027] Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings.", "Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.", "[0028] FIG. 1 is a schematic diagram of light emitting module according to one embodiment of this invention.", "As shown in FIG. 1 , the light emitting module of this embodiment includes a light-emitting unit, an optical convergent element 104 and a wavelength converting element 106 .", "In which, the light-emitting unit includes a light-emitting element 102 .", "The light-emitting element 102 emits a first light 103 with wavelength λ 1 , passing through an optical convergent element 104 , which disposed in a light path of the first light 103 from the light-emitting element 102 , making the first light 103 in wavelength λ 1 converge to a specific area, and the first light 104 becomes a second light 105 in wavelength λ 1 .", "The second light 105 emits from the optical convergent element 104 , irradiating on an incident plane of the wavelength converting element 106 .", "Having a wavelength converting material in the wavelength converting element 106 makes the second light 105 in wavelength λ 1 , after entering the incident plane and the wavelength converting element 106 , be converted to a third light 107 in wavelength λ 2 .", "[0029] According to one embodiment of the present invention, the light-emitting element 102 includes a light emitting diode chip, mounted on a substrate 108 .", "The surface of substrate 108 , which the light emitting diode chip mounted, can coat a retro-reflective material layer on it, or the substrate 108 is made by retro-reflective material.", "In which, the light emitting diode chip may be an ultraviolet light chip or a blue light chip.", "[0030] According to one embodiment of the present invention, the area of the incident plane on the wavelength converting element 106 , essentially equal to the specific area of the second light 105 in wavelength λ 1 , which comes from the optical convergent element 104 .", "[0031] According to one embodiment of the present invention, the wavelength converting element 106 includes a body and at least one wavelength converting material, which is separated in the body in a uniform or graphical or laminar way.", "[0032] According to one embodiment of the present invention, the light emitting module includes a diffusion element, which is disposed on the top of the emitting direction of the third light 107 in wavelength λ 2 , in order to diffuse, unify and receive the third light 107 in wavelength λ 2 , which passing through the wavelength converting element.", "[0033] According to one embodiment of the present invention, the optical convergent element 104 is a condensing lens.", "In some embodiments of the present invention, the condensing lens is selected from the group consisting of a convex lens, spherical lens, hemispherical lens, spherocylinder lens, cylindrical lens, molded lens, Fresnel lens and combinations thereof.", "In another embodiment, convex lens is selected from the group consisting of plane-convex lens, double-convex lens, concave-convex lens and combinations thereof.", "[0034] FIG. 2 depicts a schematic diagram of light emitting module according to one embodiment of this invention.", "As shown in FIG. 2 , the light emitting module in the embodiment includes a light unit, an optical convergence element 204 , a reflecting element 209 and a wavelength converting element 206 .", "The light unit contains a light-emitting element 202 .", "The light-emitting element 202 emits a first light 203 in wavelength λ 1 .", "The first light 203 in wavelength λ 1 is first reflected by the reflecting element 209 , changing the optical pathway, and then passing through the optical convergence element 204 .", "After passing through the optical convergence element 204 , the first light 203 in wavelength λ 1 is converged to a specific area and becoming a second light 205 in wavelength λ 1 .", "The second light 205 is first emitted from the optical convergence element 204 , then irradiate on an incident plane of a wavelength converting element 206 , which includes a wavelength converting material, after passing through the wavelength converting element 206 , the second light 205 in wavelength λ 1 is converted to a third light 207 in wavelength λ 2 .", "[0035] According to one embodiment of the present invention, the light-emitting element 202 includes a light emitting diode chip, mounted on a substrate 208 .", "The surface of substrate 208 , which the light emitting diode chip mounted, can coat a retro-reflective material layer on it, or the substrate 208 is made by retro-reflective material.", "[0036] According to one embodiment of the present invention, the area of the incident plane on the wavelength converting element 206 , essentially equal to the specific area of the second light 205 in wavelength λ 1 , which comes from the optical convergent element 204 .", "[0037] According to one embodiment of the present invention, the wavelength converting element 206 includes a body and at least one wavelength converting material, which is separated in the body in a uniform or graphical or laminar way.", "[0038] According to one embodiment of the present invention, the light emitting module includes a diffusion element, which is disposed on the top of the emitting direction of the third light 207 in wavelength λ 2 , in order to diffuse, unify and receive the third light 207 in wavelength λ 2 , which passing through the wavelength converting element.", "[0039] According to one embodiment of the present invention, the optical convergent element 204 is a condensing lens.", "In some embodiments of the present invention, the condensing lens is selected from the group consisting of a convex lens, spherical lens, hemispherical lens, spherocylinder lens, cylindrical lens, molded lens, Fresnel lens and combinations thereof.", "In another embodiment, convex lens is selected from the group consisting of plane-convex lens, double-convex lens, concave-convex lens and combinations thereof.", "[0040] FIG. 3 depicts a schematic drawing of light emitting module according to one embodiment of this invention.", "As shown in FIG. 3 , the light emitting module in the embodiment includes a light unit, an optical convergence lens array 304 , a reflecting substrate 308 and a wavelength converting element array 306 .", "In which, the light unit includes a light emitting diode chip array 302 .", "In one embodiment of the present invention, every light emitting diode chip array 302 includes encapsulating glue covering every light emitting diode chips.", "Refer to FIG. 1 and FIG. 2 , the light emitting diode chip array 302 emits first light in wavelength λ 1 , then the first light in wavelength λ 1 passing through the optical convergence lens array 304 .", "The first light is converged to a specific area and becoming a second light in wavelength λ 1 , after passing through the optical convergence lens array 304 .", "The second light is first emitted from the optical convergence lens array 304 , then irradiate on the incident plane of the wavelength converting element array 306 .", "[0041] Because the wavelength converting element array 306 includes a wavelength converting material, after entering the incident plane and passing through the wavelength converting element array 306 , the second light in wavelength λ 1 is converted to a third light in wavelength λ 2 .", "Then, the third light after being received and passing through wavelength converting element array 306 , entering a diffusion element 310 to diffuse and unify the third light.", "[0042] FIG. 4A and FIG. 4B depict schematic diagrams of light emitting module using in a strip lamp according to one embodiment of this invention.", "FIG. 4B is a cross-sectional view of strip lamp 400 plane A in FIG. 4A .", "[0043] As shown in FIG. 4B , the strip lamp 400 includes a light-emitting unit, an optical convergent lens 404 , an optical reflecting element 408 and a strip-shape wavelength converting element 406 .", "Abovementioned light-emitting unit includes a plurality of light emitting diodes 402 arranged in lines.", "Refer to FIG. 1 and FIG. 2 , a plurality of light emitting diode chips emit first light, then the first light in wavelength λ 1 passing through the optical convergence lens 404 .", "The first light is converged to a specific area and becoming a second light in wavelength λ 1 , after passing through the optical convergence lens 404 .", "The optical convergence lens 404 is on the top of the light emitting diode chips, covering all the irradiation range with the emission angle of the light emitting diode chips 402 .", "For example, the emission angle of the light emitting diode chip 402 can be 120 degrees, and the optical convergence lens 404 can cover the irradiation range for at least 120 degree for the light emitting diode chip 402 .", "After that, the second light irradiate on the incident plane of the strip-shape wavelength converting element 406 , after being emitted from the optical convergence lens 404 .", "[0044] Because the strip-shape wavelength converting element 406 includes a wavelength converting material, after entering the incident plane and passing through the strip-shape wavelength converting element 406 , the second light in wavelength λ 1 is converted to a third light in wavelength λ 2 .", "Then, the third light after being received and passing through the strip-shape wavelength converting element 406 , entering a diffusion lens 409 to diffuse and unify the third light.", "[0045] In some embodiments, the light emitting diode chip 402 may be a light emitting diode chip which emits blue or ultraviolet light in wavelength λ 1 .", "The strip-shape wavelength converting element 406 can contain a wavelength converting material, which convert λ 1 to λ 2 , where λ 2 is larger than λ 1 .", "To be specific, the light emitting diode chip 402 emits a light having wavelength λ 1 (e.g., short wavelength light like ultraviolet light or blue light), which can excite the wavelength converting element, making the light having wavelength λ 1 (e.g., ultraviolet light or blue light) convert to a light having wavelength λ 2 (e.g., red light, green light or yellow light) after passing through the strip-shape wavelength converting element 406 .", "[0046] For example, when the light emitting diode chip 402 emits ultraviolet light, the wavelength converting element can emit phosphor, which is selected from the group consisting of red color, green color, blue color, and combinations thereof, to convert the ultraviolet light to the different color emergent light.", "In one embodiment of the invention, the wavelength converting material is selected from the group consisting of phosphor, dye, pigments, quantum dots (QDs) and combinations thereof.", "[0047] Although the present invention has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible.", "Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.", "[0048] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention.", "In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims." ]
FIELD OF THE INVENTION [0001] This invention relates to a method and an apparatus for converting solid combustible waste materials, such as paper, cardboard, food, plastics, textiles, wood and the like, into fine particles which form a highly efficient fuel when fed directly into a combustion reactor, particularly such as a plasma arc waste destruction furnace. BACKGROUND OF THE INVENTION [0002] Typically, combustible solid waste is introduced into a thermal treatment furnace, such as an incinerator, in its original form or after being reduced in size by a shredder-type device. The moisture content of the waste particles is usually “as-received” and the smallest practical size achieved by a conventional shredder is several centimetres. [0003] Efforts have also been made in the past to convert waste materials, such as waste paper products, into useful forms, including fuel. One such method is disclosed in U.S. Pat. No. 4,123,489 where paper waste is processed by a rotary cutter which includes a knife cylinder having a plurality of blades for cutting the waste paper products fed into the machine into smaller pieces or particles. The cutter includes a recutter screen having a surface cooperating with the periphery of the rotating knife cylinder, providing sizing openings for further reducing the size of the pieces of paper waste. The pieces passing through the recutter screen are cut to a maximum of ⅛ inch by 2 inches which makes the material suitable for various purposes, including feeding into the die cavity of a pelletizing machine to form high quality, relatively dust-free pellets of paper material, that can be used as a fuel. Such pellets, however, do not constitute a very efficient fuel since their surface to mass ratio is not very high. [0004] There is thus a need for the conversion of solid combustible waste into a highly efficient fuel that can be readily used, for example, in a plasma fired eductor or any other combustion reactor. OBJECTS AND SUMMARY OF THE INVENTION [0005] It is an object of the present invention to provide a method and an apparatus for the conversion of combustible waste into highly efficient fuel. [0006] It is a further object to provide a solid fuel stream from such waste, which will easily burn in a plasma furnace or other combustion reactor or incinerator. [0007] Other objects and advantages of the invention will be apparent from the following description thereof. [0008] The invention, reported herein, is based on the concept of converting waste into a fuel for efficient combustion in a thermal treatment system. A fuel, for the purpose of this invention, is defined as a combustible material which has been milled to dramatically increase its surface area to mass ratio and dried to a moisture content of less than 5% by weight. [0009] The waste treatment system of the present invention subjects combustible waste, which includes materials such as paper, cardboard, food, plastics, textiles and wood, to size reducing steps achieved by suitable size reducing equipment leading to a finely pulverized product. The final pulverized product is in the form of fine particles or fibers having a high surface to mass ratio [0010] Such particles, which usually have a diameter of 15 μm or less, are fed pneumatically to a desired type of combustion reactor without any intermediate transformation into pellets or the like. This direct conveying of the fine particles into a combustion reactor, such as an incinerator or a waste treatment furnace, or a high-efficiency plasma-fired eductor of a plasma arc waste destruction system, allows them to gasify rapidly when exposed to the high heat of the reactor (about 1000° C. or higher), thus significantly increasing combustion efficiency. [0011] In essence, in accordance with the present invention, a stream of solid combustible waste is converted into a solid fuel stream consisting of finely pulverized waste material which is then fed into a combustion reactor operating at high temperature adapted to rapidly gasify the finely pulverized material. BRIEF DESCRIPTION OF THE DRAWINGS [0012] The invention will be further described with reference to the appended drawings in which: [0013] FIG. 1 is a schematic block diagram, illustrating the operation of an embodiment of the present invention; and [0014] FIG. 2 is a perspective view of equipment used within the apparatus producing the operation illustrated in FIG. 1 . DETAILED DESCRIPTION [0015] A preferred embodiment of the invention is illustrated in FIG. 1 . According to this embodiment, waste can be subjected at 10 to pulping followed by water removal and/or at 12 to shredding followed by metal extraction. Pulping, mainly of food waste, is carried out in a pulper where the size of the particles is reduced to a size suitable for milling into fine particles, which is usually to less than ½ cm. Following the pulper, water is removed to yield an extracted pulped product containing a predetermined amount of solids, e.g. approximately 50% solids, by weight. [0016] Mixed waste, including paper, cardboard, food, plastic, wood and textile wastes, is subjected at 12 to size reduction and extraction of any metal that may be present in such waste. This can be done, for instance, in a shredder where the size of such waste is reduced to small pieces suitable for milling into fine particles, for example of about 2.5 cm in size. [0017] Once the waste materials have been reduced at 10 and/or 12 to a size suitable for milling, they are subjected to milling at 14 where the size of the waste is pulverized to fine fibers or particles, preferably having a diameter of about 15 μm or less, and the moisture content is reduced in the mill from about 50% to less than 5% by weight, which represents an essentially dry condition. Such fine particles have a high surface to mass ratio and form a highly efficient fuel. Air is added to the mill to act as a carrier for the pulverized waste which can then be pneumatically fed through conduit 16 to a combustion reactor 18 , which can be an incinerator, a plasma treatment furnace, a plasma fired eductor, or the like. [0018] FIG. 2 illustrates the equipment suitable for the purposes of the present invention. Pulper 20 is provided to treat primarily food waste, but which may also contain some paper, cardboard and other pulpable materials. In this pulper, the waste is normally reduced to a size of less than 0.5 cm and the slurry exiting the pulper by conduit 22 and containing approximately 1% by weight of solids, enters a water extractor 24 where water is removed by mechanical means to yield a product in the from of pressed pulp that contains approximately 50% solids by weight. This pressed pulp is then fed onto conveyor 26 and from this conveyor to a hopper/mixer 28 where it is kept in admixture with other waste materials coming from a shredder 30 . [0019] Mixed waste, which may contain paper, cardboard, food, plastics, wood and textiles, is fed into the shredder 30 where its size is reduced to a degree suitable for milling into fine particles, for example in the neighbourhood of 2.5 cm. Such shredded waste is then conveyed via a suitable conveyor 32 to a metal extractor 34 which eliminates any metallic matter that may have been present in such waste. This can be done by passing the shredded waste through a suitable screen that will catch larger metallic pieces as well as by using magnets to remove magnetic materials and other suitable means. From the metal extractor 34 , the shredded waste is fed to the conveyor 26 to be mixed with pressed pulp. This conveyor 26 is normally an auger with cut and folded flights which mixes the material as it is conveyed to the hopper/mixer 28 . The mixed waste is metered from the hopper/mixer 28 into a mill 35 via a rotary valve 36 . In the mill 35 , the size of the waste is reduced to fine fibers or particles, preferably of about 15 μm or less in diameter and the moisture content is reduced from about 50% to about 4% by weight. The mechanical work performed by the mill 35 in pulverizing the waste, also performs the drying of the waste. Air is added to the mill 35 via conduit 38 to act as a carrier for the pulverized waste which is then fed pneumatically via conduit 40 to a combustion reactor 42 . In this case, the combustion reactor 42 consists of a plasma arc waste destruction system and the pulverized waste is fed into the plasma-fired eductor 44 at the inlet thereof The pulverized waste is fully combusted in this system to produce CO 2 and H 2 O at the outlet 46 . [0020] The invention is not limited to the specific embodiments described above, and includes various modifications obvious to those skilled in the art, without departing from the scope of the following claims.
Solid combustible waste materials are converted into highly efficient fuel by subjecting such materials to size reduction in suitable size-reducing equipment. The last piece of the equipment is a mill which pulverizes the waste materials into fine particles having a high surface to mass ratio and forming a highly efficient fuel when these particles are directly injected into a combustion reactor operating at high temperature.
Provide a concise summary of the essential information conveyed in the given context.
[ "FIELD OF THE INVENTION [0001] This invention relates to a method and an apparatus for converting solid combustible waste materials, such as paper, cardboard, food, plastics, textiles, wood and the like, into fine particles which form a highly efficient fuel when fed directly into a combustion reactor, particularly such as a plasma arc waste destruction furnace.", "BACKGROUND OF THE INVENTION [0002] Typically, combustible solid waste is introduced into a thermal treatment furnace, such as an incinerator, in its original form or after being reduced in size by a shredder-type device.", "The moisture content of the waste particles is usually “as-received”", "and the smallest practical size achieved by a conventional shredder is several centimetres.", "[0003] Efforts have also been made in the past to convert waste materials, such as waste paper products, into useful forms, including fuel.", "One such method is disclosed in U.S. Pat. No. 4,123,489 where paper waste is processed by a rotary cutter which includes a knife cylinder having a plurality of blades for cutting the waste paper products fed into the machine into smaller pieces or particles.", "The cutter includes a recutter screen having a surface cooperating with the periphery of the rotating knife cylinder, providing sizing openings for further reducing the size of the pieces of paper waste.", "The pieces passing through the recutter screen are cut to a maximum of ⅛ inch by 2 inches which makes the material suitable for various purposes, including feeding into the die cavity of a pelletizing machine to form high quality, relatively dust-free pellets of paper material, that can be used as a fuel.", "Such pellets, however, do not constitute a very efficient fuel since their surface to mass ratio is not very high.", "[0004] There is thus a need for the conversion of solid combustible waste into a highly efficient fuel that can be readily used, for example, in a plasma fired eductor or any other combustion reactor.", "OBJECTS AND SUMMARY OF THE INVENTION [0005] It is an object of the present invention to provide a method and an apparatus for the conversion of combustible waste into highly efficient fuel.", "[0006] It is a further object to provide a solid fuel stream from such waste, which will easily burn in a plasma furnace or other combustion reactor or incinerator.", "[0007] Other objects and advantages of the invention will be apparent from the following description thereof.", "[0008] The invention, reported herein, is based on the concept of converting waste into a fuel for efficient combustion in a thermal treatment system.", "A fuel, for the purpose of this invention, is defined as a combustible material which has been milled to dramatically increase its surface area to mass ratio and dried to a moisture content of less than 5% by weight.", "[0009] The waste treatment system of the present invention subjects combustible waste, which includes materials such as paper, cardboard, food, plastics, textiles and wood, to size reducing steps achieved by suitable size reducing equipment leading to a finely pulverized product.", "The final pulverized product is in the form of fine particles or fibers having a high surface to mass ratio [0010] Such particles, which usually have a diameter of 15 μm or less, are fed pneumatically to a desired type of combustion reactor without any intermediate transformation into pellets or the like.", "This direct conveying of the fine particles into a combustion reactor, such as an incinerator or a waste treatment furnace, or a high-efficiency plasma-fired eductor of a plasma arc waste destruction system, allows them to gasify rapidly when exposed to the high heat of the reactor (about 1000° C. or higher), thus significantly increasing combustion efficiency.", "[0011] In essence, in accordance with the present invention, a stream of solid combustible waste is converted into a solid fuel stream consisting of finely pulverized waste material which is then fed into a combustion reactor operating at high temperature adapted to rapidly gasify the finely pulverized material.", "BRIEF DESCRIPTION OF THE DRAWINGS [0012] The invention will be further described with reference to the appended drawings in which: [0013] FIG. 1 is a schematic block diagram, illustrating the operation of an embodiment of the present invention;", "and [0014] FIG. 2 is a perspective view of equipment used within the apparatus producing the operation illustrated in FIG. 1 .", "DETAILED DESCRIPTION [0015] A preferred embodiment of the invention is illustrated in FIG. 1 .", "According to this embodiment, waste can be subjected at 10 to pulping followed by water removal and/or at 12 to shredding followed by metal extraction.", "Pulping, mainly of food waste, is carried out in a pulper where the size of the particles is reduced to a size suitable for milling into fine particles, which is usually to less than ½ cm.", "Following the pulper, water is removed to yield an extracted pulped product containing a predetermined amount of solids, e.g. approximately 50% solids, by weight.", "[0016] Mixed waste, including paper, cardboard, food, plastic, wood and textile wastes, is subjected at 12 to size reduction and extraction of any metal that may be present in such waste.", "This can be done, for instance, in a shredder where the size of such waste is reduced to small pieces suitable for milling into fine particles, for example of about 2.5 cm in size.", "[0017] Once the waste materials have been reduced at 10 and/or 12 to a size suitable for milling, they are subjected to milling at 14 where the size of the waste is pulverized to fine fibers or particles, preferably having a diameter of about 15 μm or less, and the moisture content is reduced in the mill from about 50% to less than 5% by weight, which represents an essentially dry condition.", "Such fine particles have a high surface to mass ratio and form a highly efficient fuel.", "Air is added to the mill to act as a carrier for the pulverized waste which can then be pneumatically fed through conduit 16 to a combustion reactor 18 , which can be an incinerator, a plasma treatment furnace, a plasma fired eductor, or the like.", "[0018] FIG. 2 illustrates the equipment suitable for the purposes of the present invention.", "Pulper 20 is provided to treat primarily food waste, but which may also contain some paper, cardboard and other pulpable materials.", "In this pulper, the waste is normally reduced to a size of less than 0.5 cm and the slurry exiting the pulper by conduit 22 and containing approximately 1% by weight of solids, enters a water extractor 24 where water is removed by mechanical means to yield a product in the from of pressed pulp that contains approximately 50% solids by weight.", "This pressed pulp is then fed onto conveyor 26 and from this conveyor to a hopper/mixer 28 where it is kept in admixture with other waste materials coming from a shredder 30 .", "[0019] Mixed waste, which may contain paper, cardboard, food, plastics, wood and textiles, is fed into the shredder 30 where its size is reduced to a degree suitable for milling into fine particles, for example in the neighbourhood of 2.5 cm.", "Such shredded waste is then conveyed via a suitable conveyor 32 to a metal extractor 34 which eliminates any metallic matter that may have been present in such waste.", "This can be done by passing the shredded waste through a suitable screen that will catch larger metallic pieces as well as by using magnets to remove magnetic materials and other suitable means.", "From the metal extractor 34 , the shredded waste is fed to the conveyor 26 to be mixed with pressed pulp.", "This conveyor 26 is normally an auger with cut and folded flights which mixes the material as it is conveyed to the hopper/mixer 28 .", "The mixed waste is metered from the hopper/mixer 28 into a mill 35 via a rotary valve 36 .", "In the mill 35 , the size of the waste is reduced to fine fibers or particles, preferably of about 15 μm or less in diameter and the moisture content is reduced from about 50% to about 4% by weight.", "The mechanical work performed by the mill 35 in pulverizing the waste, also performs the drying of the waste.", "Air is added to the mill 35 via conduit 38 to act as a carrier for the pulverized waste which is then fed pneumatically via conduit 40 to a combustion reactor 42 .", "In this case, the combustion reactor 42 consists of a plasma arc waste destruction system and the pulverized waste is fed into the plasma-fired eductor 44 at the inlet thereof The pulverized waste is fully combusted in this system to produce CO 2 and H 2 O at the outlet 46 .", "[0020] The invention is not limited to the specific embodiments described above, and includes various modifications obvious to those skilled in the art, without departing from the scope of the following claims." ]
CROSS REFERENCE TO RELATED APPLICATIONS [0001] The present application claims the benefit of U.S. provisional patent application Ser. No. 60/909,779, filed Apr. 3, 2007 the entire disclosure of which is incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] Night vision systems include image intensification, thermal imaging, and fusion monoculars, binoculars, and goggles, whether hand-held, weapon mounted, or helmet mounted. Standard night vision systems are typically equipped with one or more image intensifier tubes to allow an operator to see visible wavelengths of radiation (approximately 400 nm to approximately 900 nm). They work by collecting the tiny amounts of light, including the lower portion of the infrared light spectrum, that are present but may be imperceptible to our eyes, and amplifying it to the point that an operator can easily observe the image through an eyepiece. These devices have been used by soldier and law enforcement personnel to see in low light conditions, for example at night or in caves and darkened buildings. A drawback to night vision goggles is that they cannot see through smoke and heavy sand storms and cannot see a person hidden under camouflage. [0003] Infrared thermal imagers allow an operator to see people and objects because they emit thermal energy. These devices operate by capturing the upper portion of the infrared light spectrum, which is emitted as heat by objects instead of simply reflected as light. Hotter objects, such as warm bodies, emit more of this wavelength than cooler objects like trees or buildings. Since the primary source of infrared radiation is heat or thermal radiation, any object that has a temperature radiates in the infrared. One advantage of infrared sensors is that they are less attenuated by smoke and dust and a drawback is that they typically do not have sufficient resolution and sensitivity to provide acceptable imagery of the scene. [0004] Fusion systems have been developed that combine image intensification with infrared sensing. The image intensification information and the infrared information are fused together to provide a fused image that provides benefits over just image intensification or just infrared sensing. BRIEF DESCRIPTION OF THE DRAWINGS [0005] For a better understanding of the invention, together with other objects, features and advantages, reference should be made to the following detailed description which should be read in conjunction with the following figures wherein like numerals represent like parts: [0006] FIG. 1 is an isometric view of a fusion night vision system consistent with an embodiment of the invention. [0007] FIG. 2 is a block diagram of the fusion night vision system of FIG. 1 . [0008] FIG. 3 is a plot of misregistration of pixels due to parallax as a function of distance to target for the fusion night vision system of FIG. 1 . [0009] FIG. 4 is a block diagram of a parallax correction circuit consistent with an embodiment of the invention. [0010] FIG. 5 is a block diagram of a horizontal/vertical feature filter circuit consistent with an embodiment of the invention. [0011] FIG. 6A is a schematic of a mechanical range finder consistent with an embodiment of the invention. [0012] FIG. 6B is a switch state diagram for the range finder of FIG. 6A consistent with an embodiment of the invention. [0013] FIG. 6C is a coarse parallax correction look-up table consistent with an embodiment of the invention. [0014] FIG. 7A is an image of a scene from a first sensor of the fusion night vision system of FIG. 1 . [0015] FIG. 7B is the output of the image of FIG. 7A after passing though a horizontal/vertical feature filter circuit consistent with an embodiment of the invention. [0016] FIG. 7C is the output of the image of FIG. 7B after passing though a binary filter circuit consistent with an embodiment of the invention. [0017] FIG. 7D is an image of a scene from a second sensor of the fusion night vision system of FIG. 1 . [0018] FIG. 7E is the output of the image of FIG. 7D after passing though a horizontal/vertical feature filter circuit consistent with an embodiment of the invention. [0019] FIG. 7F is the output of the image of FIG. 7E after passing though a binary filter circuit consistent with an embodiment of the invention. [0020] FIG. 7G is a fused image viewable through an eyepiece of the fusion night vision system of FIG. 1 . [0021] FIG. 8 is a plot of number of matching points versus translation useful in the parallax correction circuit of FIG. 4 consistent with an embodiment of the invention. [0022] FIG. 9 is a fusion alignment flow chart consistent with an embodiment of the invention. DETAILED DESCRIPTION [0023] FIG. 1 is an isometric view and FIG. 2 is a block diagram of a fusion night vision system 100 consistent with an embodiment of the invention. The night vision system electronics and optics may be housed in a housing 102 which may be mounted on a weapon 112 to aid in identifying a threat and aiming of the weapon. The night vision system 100 may have a first sensor 204 located behind first objective optics 104 and a second sensor 208 located behind second objective optics 106 . The first sensor 204 may be configured to image scene information in a first range of wavelengths (7,000 nm-14,000 nm) and the second sensor 208 may be configured to image scene information from a second range of wavelengths (400 nm to 900 nm). The first sensor 204 may be an uncooled microbolometer focal plane array sensitive to long wave infrared radiation and the second sensor may be a digital image intensification (DI 2 ) device such as the electron bombarded active pixel sensor (EBAPS) sensitive to shorter wavelength radiation. Each sensor 204 , 208 may have a two-dimensional array of detector elements that is translated into electric impulses that are communicated to signal processing electronics 202 . The signal processing electronics 202 may then translate the electric impulses into data for a display 220 for viewing through an eyepiece optics 108 . Other sensor/detector technologies including cooled long wave or mid wave infrared focal plane array, digital image intensification tube, a charge-coupled device (CCD) or complementary metal oxide semiconductor (CMOS) imager, or short wave infrared InGaAs array may be used without departing from the invention. [0024] The system may have one or more actuators 110 for controlling system operation. Although the objective optics are shown spaced in the horizontal direction, they may be spaced in the vertical direction or a combination of vertical and horizontal without departing from the invention. Although the fusion night vision device is shown as a monocular, it may be binocular or biocular without departing from the invention. Although the fusion night vision system is shown as being weapon mountable, it may be helmet mounted or handheld without departing from the invention. [0025] The fusion night vision system 100 may have the optical axis OA 1 of the first objective optics 104 physically offset a fixed distance “D” from the optical axis OA 2 of the second objective optics 106 . The optical axes of the first and second objective optics 104 , 106 are typically factory aligned such that the image from the first sensor is fused and is aligned with the image from the second sensor for viewing by an operator as a unified image in the display 220 through the eyepiece 108 when the object/target being viewed is at a predetermined distance, typically aligned at infinity. At distances different from the predetermined distance, parallax can cause a misalignment of the two images as viewed in the eyepiece. The parallax problem may exist if the objective optics 104 , 106 are offset in the horizontal as well as the vertical directions. The eyepiece 108 may have one or more ocular lenses for magnifying and/or focusing the fused image. The display 220 may be a miniature flat panel display, for example an organic light emitting diode (OLED) microdisplay or a liquid crystal display (LCD). [0026] FIG. 3 is a plot of misregistration of pixels due to parallax as a function of distance to target for the fusion night vision system 100 . The plot shows that for the system 100 with the optical axes OA 1 , OA 2 of objective optics 104 , 106 spaced by 1.6″, the image from the first sensor will be misregistered with the image from the second sensor in the display 220 by more than ten (10) pixels at a distance to target of less than 25 meters. The system 100 may reduce the misregistration using a coarse correction based on the position of one or both of the movable focus rings 104 A, 106 A and a fine correction based upon an autoalignment circuit. The system 100 may shift the position of the image from each sensor an equal and opposite number of pixels prior to fusion and display in order to maintain boresight of the system 100 to the weapon 112 . Shifting one of the images one more, or one less, pixel than the other image prior to fusion and display may be done without departing from the invention. Alternatively, the system 100 may reduce misregistration using just the autoalignment circuit, i.e without the coarse correction. [0027] Scene information from the first sensor 204 may enter an analog to digital conversion circuit 206 before entering signal processing electronics 202 and scene information from the second sensor 208 may enter the signal processing electronics 202 in digital form directly. Batteries 214 may provide power to a low voltage power supply and controller 212 which provides conditioned power distributed throughout the system. The signal processing electronics 202 may include a digital processing circuit 202 A, a display formatter circuit 202 B, and a parallax correction circuit 202 C. [0028] FIG. 4 is a block diagram of the parallax correction circuit 202 C consistent with an embodiment of the invention. The parallax correction circuit 202 C may be part of the digital processing circuit 202 A. The first sensor 204 may be a microbolometer array with 320×240 pixels and generate an output 402 and the second sensor 208 may be an EBAPS device with 1280×1024 pixels and generate an output 404 . An interpolation circuit 406 may scale/interpolate the output from the first sensor 204 so it is approximately the same size in number of pixels as the output from the second sensor 208 . The output from the interpolation circuit 406 and the second sensor 208 may be directed to an alignment filter 408 and respective first and second pixel shift circuits 412 , 414 . The alignment filter 408 may first pass the scene information from the first sensor 204 and the second sensor 208 through a horizontal/vertical feature filter circuit 408 A to define edges in the scene information and then through a second filter 408 B that converts the output of the horizontal/vertical feature filter circuit 408 A to a binary output. Edges may be defined as pixel intensity discontinuities or localized intensity gradients within an image. Edges may help characterize an object boundary and therefore may be useful for detection of objects in a scene. Known edge detection circuits are disclosed in Fundamentals of Digital Image Processing authored by Anil K. Jain and published by Prentice-Hall, Inc., and are incorporated herein by reference in their entirety. For each image originating from the first sensor 204 and the second sensor 208 , the horizontal/vertical feature filter circuit 408 A may produce an image of edges and the second filter 408 B may convert the image into a binary map of edges with each pixel location assigned a value of one (1) or zero (0) based upon the edge intensity. Any pixel at the output of the horizontal/vertical feature filter circuit 408 A with pixel value equal to or above a predetermined positive threshold (for example +16 with an 8-bit bipolar image) or equal to or below a predetermined negative threshold (for example −16 with an 8-bit bipolar image) may be assigned to a value of one (1) by the binary filter 408 B. Any pixel at the output of the horizontal/vertical feature filter circuit 408 A with pixel value between the predetermined positive and negative threshold may be assigned the value of zero (0) by the binary filter 408 B. The binary edge map of 1's and 0's produced at the binary filter output for each image originating from the first sensor 204 and the second sensor 208 is temporarily stored within the buffer memory 430 accessible by the alignment correlation circuit 410 . [0029] The alignment correlation circuit 410 accesses the binary edge maps held within the buffer memory 430 and may use a coarse alignment estimate based on “rough” distance to target information to speed up processing. The “rough” distance to target information may be provided by a mechanical range finder 432 or other means including input by the user. [0030] FIG. 5 is a block diagram of the horizontal/vertical feature filter circuit 408 A consistent with the invention. The horizontal/vertical feature filter circuit 408 A may include a multi-row, multi-column buffer 520 and a multi-row, multi-column convolver 522 and a multi-row, multi-column convolution kernel 524 . Other values in the convolution kernel 524 may be used without departing from the invention. Although the convolver is shown as being 5×5, other sized convolver with extent smaller or larger may be used without departing from the invention, for example a 3×3, 7×7 or 9×9 convolver may be used. Although the convolution kernel 524 as shown is designed to locate vertical features within an image (as may be used for systems with horizontal placement of the objective optics 104 , 106 ) it should be readily apparent that by transposing the kernel 90° the filter will perform equally well in locating horizontal image features (as may be used for systems with vertical placement of the objective optics 104 , 106 ) without departing from the invention. [0031] A mechanical range finder may require the operator to focus one of the focus rings 104 A, 106 A on a target and a linear or rotational position sensor could be used to determine the distance to target (see FIGS. 6A-6C and discussed in further detail below). Alternatively, a mechanical circuit may include a linear or rotary potentiometer mechanically coupled to one of the focus rings 104 A, 106 A. In an alternative embodiment, the system may accept inputs from a user regarding the distance to target. The input may be received through a near/far actuator or a menu selection. The system may be designed so the operator selects the far mode when the object being viewed is greater than 100 meters away and the operator selects the near mode when the object being viewed is less than 100 meters away. Distances other than 100 meters may be chosen without departing from the invention. The fusion night vision system may also incorporate multiple distance choices, for example close, less than 25 meters; mid range, 25-50 meters; long range, 50-100 meters; real long range, greater than 100 meters without departing from the invention. [0032] The alignment correlation circuit 410 may receive the distance to target information from the mechanical range finder 432 to establish a coarse estimate of the amount of image shift required. Using the coarse estimate as an initial starting point the alignment correlation circuit 410 may then compare the binary maps held within buffer memory 430 , corresponding to the location of object edges in the images produced by the first sensor 204 and the second sensor 208 , to determine a fine alignment estimate. The alignment correlation circuit 410 may start the comparison of the binary edge maps shifted relative to each other based on the coarse estimate and then translate them left or right until a best match is found. A best match may be found when the number of matching pixels within the edge maps is highest, i.e. the peak of the correlation function, for the pixel shift attempted. For each increment in image shift, the alignment correlation circuit 410 may calculate the corresponding value of the correlation function by summing over all pixel locations the result of performing a pixel-by-pixel logical “and” operation between the two binary maps under evaluation with the net result being a count of all pixel locations for which a value of one (1) is present in both binary edge maps. Alternatively, the alignment correlation circuit 410 may use only a central portion of the binary maps without departing from the invention. [0033] For the example shown in FIG. 8 , the alignment correlation circuit has determined that the image from the first sensor should be shifted left (minus) three (3) pixels relative to the image from the second sensor as indicated by the peak in the correlation function as plotted. It should be readily apparent to those skilled in the art that a correlation circuit based upon a logical “nor” operation would produce equally valid results without departing from the invention if the use of 0's and 1's within the binary edge maps were interchanged. [0034] The output of the alignment correlation circuit 410 may instruct the first pixel shift circuit 412 to shift the interpolated output from the first sensor 204 to the left one (1) pixel and the second pixel shift circuit 414 to shift the output from the second sensor 208 to the right two (2) pixels where the sum total shift in pixels is equal to the sum of the coarse and fine alignment estimates. The outputs of the pixel shift circuits 412 , 414 may be inputted into an image combiner 416 to combine the two images into a single fused image outputted to the display formatter 202 B. An image combiner 416 may be a circuit that adds or fuses, in analog or digital form, the image from the first sensor 204 with the image from the second sensor 208 or may employ a more complex circuit designed for image fusion such as the Acadia processor from Pyramid Vision. [0035] FIG. 6A is a schematic of a mechanical range finder, FIG. 6B is a switch state diagram, and FIG. 6C is a look up table consistent with the invention. Sensors SW 1 , SW 2 , for example Hall effect switches, may be located in the housing 102 adjacent a rotatable or translatable focus ring 104 A, 106 A that surrounds the objective optics 104 , 106 . The user can rotate or translate the focus ring 104 A, 106 A clockwise or counter-clockwise from near N to far F as the user attempts to focus on a target. As the focus ring 104 A, 106 A is rotated, the state of the sensors SW 1 , SW 2 may be read by a processor 620 . The processor 620 may be part of the low voltage power supply and controller 212 or may be part of the signal processing electronics 202 . A series of magnets 652 in close proximity, or a single arcuate magnet, may be coupled to the focus ring 104 A, 106 A in an arcuate path. The magnets 652 may be located in holes formed in the focus ring 104 A, 106 A. The location and spacing of the sensors relative to the magnets may depend on the angular rotation of the focus ring 104 A, 106 A from near N to far F. The location of the sensors SW 1 , SW 2 and the magnet(s) 652 may also be swapped without departing from the invention. [0036] FIG. 6C is a coarse parallax correction look-up table consistent with the invention. As the distance to target changes, the processor 620 may provide the corresponding estimate for coarse alignment in pixels of image shift to the alignment correlation circuit 410 . For example, when a target is approximately 75 meters away, the range finder 432 may send a signal to the alignment correlation circuit 410 that the images need to be shifted by a nominal amount of five (5) pixels in total. [0037] FIG. 7A is an image of a scene from the first sensor of the fusion night vision system 100 ; FIG. 7D is an image of the same scene from the second sensor of the fusion night vision system 100 ; and FIG. 7G is a fused/combined image viewable through the eyepiece 108 of the fusion night vision system 100 . The fused image provides more scene information than either of the individual images. In FIG. 7D , an antenna 702 is viewable with the second sensor 208 but not with the first sensor 204 and in the FIG. 7A the doorway of the trailer is viewable with the first sensor 204 but not the second sensor 208 . FIG. 7G shows the fused image in which the antenna 702 and the trailer doorway 704 are viewable. FIG. 7B shows the output of the horizontal/vertical feature filter circuit 408 A and FIG. 7C shows the output of the binary filter 408 B for the first sensor 204 . FIG. 7E shows the output of the horizontal/vertical feature filter circuit 408 A and FIG. 7F shows the output of the binary filter 408 B for the second sensor 208 . [0038] Certain embodiments of the invention can be implemented in hardware, software, firmware, or a combination thereof. In one embodiment, the parallax correction circuit is implemented in software or firmware that is stored in a memory and that is executable by a suitable instruction execution system. If implemented in hardware, as in an alternative embodiment, the circuits can be implemented with any or a combination of the following technologies, which are well known in the art: a discrete logic circuit(s) having logic gates for implementing logic functions upon data signals, an application specific integrated circuit (ASIC) having appropriate combinational logic gates, a programmable logic device (PLD), a field programmable gate array (FPGA), etc. [0039] FIG. 9 is a fusion alignment flow chart consistent with an embodiment of the invention. The first sensor acquires data representative of a scene at block 902 and the second sensor acquires data representative of the same scene at block 912 . The output of the first sensor is received by the first shift pixel circuit at block 920 and the horizontal/vertical feature filter circuit at block 904 and output of the second sensor is received by the second shift pixel circuit at block 922 and the horizontal/vertical feature filter circuit at block 914 . The horizontal/vertical feature filter circuit filters the data from each sensor to define edges and then outputs the data from the first sensor to the binary filter at block 906 and the data from the second sensor to the binary filter at block 916 . The binary filter converts each pixel to one of two unique values (e.g. 0 and 1). The outputs of the binary filter circuits (binary edge maps) are then inputted to the buffer memory at block 908 . The alignment correlation circuit at block 909 may then start the comparison by translating the binary edge maps temporarily stored within the buffer memory and corresponding to images from the first and the second sensors left and right about the coarse align position until a best match is found. The alignment correlation circuit then instructs the pixel shift circuits how many pixels to move the image and in which direction at block 920 , 922 . After the first and second images are shifted (if necessary), the images are combined in a combiner at block 910 and outputted to the display formatter. [0040] Although several embodiments of the invention have been described in detail herein, the invention is not limited hereto. It will be appreciated by those having ordinary skill in the art that various modifications can be made without materially departing from the novel and advantageous teachings of the invention. Accordingly, the embodiments disclosed herein are by way of example. It is to be understood that the scope of the invention is not to be limited thereby.
A fusion night vision system corrects for parallax error by comparing an image from a first sensor with an image from a second sensor.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "CROSS REFERENCE TO RELATED APPLICATIONS [0001] The present application claims the benefit of U.S. provisional patent application Ser.", "No. 60/909,779, filed Apr. 3, 2007 the entire disclosure of which is incorporated herein by reference.", "BACKGROUND OF THE INVENTION [0002] Night vision systems include image intensification, thermal imaging, and fusion monoculars, binoculars, and goggles, whether hand-held, weapon mounted, or helmet mounted.", "Standard night vision systems are typically equipped with one or more image intensifier tubes to allow an operator to see visible wavelengths of radiation (approximately 400 nm to approximately 900 nm).", "They work by collecting the tiny amounts of light, including the lower portion of the infrared light spectrum, that are present but may be imperceptible to our eyes, and amplifying it to the point that an operator can easily observe the image through an eyepiece.", "These devices have been used by soldier and law enforcement personnel to see in low light conditions, for example at night or in caves and darkened buildings.", "A drawback to night vision goggles is that they cannot see through smoke and heavy sand storms and cannot see a person hidden under camouflage.", "[0003] Infrared thermal imagers allow an operator to see people and objects because they emit thermal energy.", "These devices operate by capturing the upper portion of the infrared light spectrum, which is emitted as heat by objects instead of simply reflected as light.", "Hotter objects, such as warm bodies, emit more of this wavelength than cooler objects like trees or buildings.", "Since the primary source of infrared radiation is heat or thermal radiation, any object that has a temperature radiates in the infrared.", "One advantage of infrared sensors is that they are less attenuated by smoke and dust and a drawback is that they typically do not have sufficient resolution and sensitivity to provide acceptable imagery of the scene.", "[0004] Fusion systems have been developed that combine image intensification with infrared sensing.", "The image intensification information and the infrared information are fused together to provide a fused image that provides benefits over just image intensification or just infrared sensing.", "BRIEF DESCRIPTION OF THE DRAWINGS [0005] For a better understanding of the invention, together with other objects, features and advantages, reference should be made to the following detailed description which should be read in conjunction with the following figures wherein like numerals represent like parts: [0006] FIG. 1 is an isometric view of a fusion night vision system consistent with an embodiment of the invention.", "[0007] FIG. 2 is a block diagram of the fusion night vision system of FIG. 1 .", "[0008] FIG. 3 is a plot of misregistration of pixels due to parallax as a function of distance to target for the fusion night vision system of FIG. 1 .", "[0009] FIG. 4 is a block diagram of a parallax correction circuit consistent with an embodiment of the invention.", "[0010] FIG. 5 is a block diagram of a horizontal/vertical feature filter circuit consistent with an embodiment of the invention.", "[0011] FIG. 6A is a schematic of a mechanical range finder consistent with an embodiment of the invention.", "[0012] FIG. 6B is a switch state diagram for the range finder of FIG. 6A consistent with an embodiment of the invention.", "[0013] FIG. 6C is a coarse parallax correction look-up table consistent with an embodiment of the invention.", "[0014] FIG. 7A is an image of a scene from a first sensor of the fusion night vision system of FIG. 1 .", "[0015] FIG. 7B is the output of the image of FIG. 7A after passing though a horizontal/vertical feature filter circuit consistent with an embodiment of the invention.", "[0016] FIG. 7C is the output of the image of FIG. 7B after passing though a binary filter circuit consistent with an embodiment of the invention.", "[0017] FIG. 7D is an image of a scene from a second sensor of the fusion night vision system of FIG. 1 .", "[0018] FIG. 7E is the output of the image of FIG. 7D after passing though a horizontal/vertical feature filter circuit consistent with an embodiment of the invention.", "[0019] FIG. 7F is the output of the image of FIG. 7E after passing though a binary filter circuit consistent with an embodiment of the invention.", "[0020] FIG. 7G is a fused image viewable through an eyepiece of the fusion night vision system of FIG. 1 .", "[0021] FIG. 8 is a plot of number of matching points versus translation useful in the parallax correction circuit of FIG. 4 consistent with an embodiment of the invention.", "[0022] FIG. 9 is a fusion alignment flow chart consistent with an embodiment of the invention.", "DETAILED DESCRIPTION [0023] FIG. 1 is an isometric view and FIG. 2 is a block diagram of a fusion night vision system 100 consistent with an embodiment of the invention.", "The night vision system electronics and optics may be housed in a housing 102 which may be mounted on a weapon 112 to aid in identifying a threat and aiming of the weapon.", "The night vision system 100 may have a first sensor 204 located behind first objective optics 104 and a second sensor 208 located behind second objective optics 106 .", "The first sensor 204 may be configured to image scene information in a first range of wavelengths (7,000 nm-14,000 nm) and the second sensor 208 may be configured to image scene information from a second range of wavelengths (400 nm to 900 nm).", "The first sensor 204 may be an uncooled microbolometer focal plane array sensitive to long wave infrared radiation and the second sensor may be a digital image intensification (DI 2 ) device such as the electron bombarded active pixel sensor (EBAPS) sensitive to shorter wavelength radiation.", "Each sensor 204 , 208 may have a two-dimensional array of detector elements that is translated into electric impulses that are communicated to signal processing electronics 202 .", "The signal processing electronics 202 may then translate the electric impulses into data for a display 220 for viewing through an eyepiece optics 108 .", "Other sensor/detector technologies including cooled long wave or mid wave infrared focal plane array, digital image intensification tube, a charge-coupled device (CCD) or complementary metal oxide semiconductor (CMOS) imager, or short wave infrared InGaAs array may be used without departing from the invention.", "[0024] The system may have one or more actuators 110 for controlling system operation.", "Although the objective optics are shown spaced in the horizontal direction, they may be spaced in the vertical direction or a combination of vertical and horizontal without departing from the invention.", "Although the fusion night vision device is shown as a monocular, it may be binocular or biocular without departing from the invention.", "Although the fusion night vision system is shown as being weapon mountable, it may be helmet mounted or handheld without departing from the invention.", "[0025] The fusion night vision system 100 may have the optical axis OA 1 of the first objective optics 104 physically offset a fixed distance “D”", "from the optical axis OA 2 of the second objective optics 106 .", "The optical axes of the first and second objective optics 104 , 106 are typically factory aligned such that the image from the first sensor is fused and is aligned with the image from the second sensor for viewing by an operator as a unified image in the display 220 through the eyepiece 108 when the object/target being viewed is at a predetermined distance, typically aligned at infinity.", "At distances different from the predetermined distance, parallax can cause a misalignment of the two images as viewed in the eyepiece.", "The parallax problem may exist if the objective optics 104 , 106 are offset in the horizontal as well as the vertical directions.", "The eyepiece 108 may have one or more ocular lenses for magnifying and/or focusing the fused image.", "The display 220 may be a miniature flat panel display, for example an organic light emitting diode (OLED) microdisplay or a liquid crystal display (LCD).", "[0026] FIG. 3 is a plot of misregistration of pixels due to parallax as a function of distance to target for the fusion night vision system 100 .", "The plot shows that for the system 100 with the optical axes OA 1 , OA 2 of objective optics 104 , 106 spaced by 1.6″, the image from the first sensor will be misregistered with the image from the second sensor in the display 220 by more than ten (10) pixels at a distance to target of less than 25 meters.", "The system 100 may reduce the misregistration using a coarse correction based on the position of one or both of the movable focus rings 104 A, 106 A and a fine correction based upon an autoalignment circuit.", "The system 100 may shift the position of the image from each sensor an equal and opposite number of pixels prior to fusion and display in order to maintain boresight of the system 100 to the weapon 112 .", "Shifting one of the images one more, or one less, pixel than the other image prior to fusion and display may be done without departing from the invention.", "Alternatively, the system 100 may reduce misregistration using just the autoalignment circuit, i.e without the coarse correction.", "[0027] Scene information from the first sensor 204 may enter an analog to digital conversion circuit 206 before entering signal processing electronics 202 and scene information from the second sensor 208 may enter the signal processing electronics 202 in digital form directly.", "Batteries 214 may provide power to a low voltage power supply and controller 212 which provides conditioned power distributed throughout the system.", "The signal processing electronics 202 may include a digital processing circuit 202 A, a display formatter circuit 202 B, and a parallax correction circuit 202 C. [0028] FIG. 4 is a block diagram of the parallax correction circuit 202 C consistent with an embodiment of the invention.", "The parallax correction circuit 202 C may be part of the digital processing circuit 202 A. The first sensor 204 may be a microbolometer array with 320×240 pixels and generate an output 402 and the second sensor 208 may be an EBAPS device with 1280×1024 pixels and generate an output 404 .", "An interpolation circuit 406 may scale/interpolate the output from the first sensor 204 so it is approximately the same size in number of pixels as the output from the second sensor 208 .", "The output from the interpolation circuit 406 and the second sensor 208 may be directed to an alignment filter 408 and respective first and second pixel shift circuits 412 , 414 .", "The alignment filter 408 may first pass the scene information from the first sensor 204 and the second sensor 208 through a horizontal/vertical feature filter circuit 408 A to define edges in the scene information and then through a second filter 408 B that converts the output of the horizontal/vertical feature filter circuit 408 A to a binary output.", "Edges may be defined as pixel intensity discontinuities or localized intensity gradients within an image.", "Edges may help characterize an object boundary and therefore may be useful for detection of objects in a scene.", "Known edge detection circuits are disclosed in Fundamentals of Digital Image Processing authored by Anil K. Jain and published by Prentice-Hall, Inc., and are incorporated herein by reference in their entirety.", "For each image originating from the first sensor 204 and the second sensor 208 , the horizontal/vertical feature filter circuit 408 A may produce an image of edges and the second filter 408 B may convert the image into a binary map of edges with each pixel location assigned a value of one (1) or zero (0) based upon the edge intensity.", "Any pixel at the output of the horizontal/vertical feature filter circuit 408 A with pixel value equal to or above a predetermined positive threshold (for example +16 with an 8-bit bipolar image) or equal to or below a predetermined negative threshold (for example −16 with an 8-bit bipolar image) may be assigned to a value of one (1) by the binary filter 408 B. Any pixel at the output of the horizontal/vertical feature filter circuit 408 A with pixel value between the predetermined positive and negative threshold may be assigned the value of zero (0) by the binary filter 408 B. The binary edge map of 1's and 0's produced at the binary filter output for each image originating from the first sensor 204 and the second sensor 208 is temporarily stored within the buffer memory 430 accessible by the alignment correlation circuit 410 .", "[0029] The alignment correlation circuit 410 accesses the binary edge maps held within the buffer memory 430 and may use a coarse alignment estimate based on “rough”", "distance to target information to speed up processing.", "The “rough”", "distance to target information may be provided by a mechanical range finder 432 or other means including input by the user.", "[0030] FIG. 5 is a block diagram of the horizontal/vertical feature filter circuit 408 A consistent with the invention.", "The horizontal/vertical feature filter circuit 408 A may include a multi-row, multi-column buffer 520 and a multi-row, multi-column convolver 522 and a multi-row, multi-column convolution kernel 524 .", "Other values in the convolution kernel 524 may be used without departing from the invention.", "Although the convolver is shown as being 5×5, other sized convolver with extent smaller or larger may be used without departing from the invention, for example a 3×3, 7×7 or 9×9 convolver may be used.", "Although the convolution kernel 524 as shown is designed to locate vertical features within an image (as may be used for systems with horizontal placement of the objective optics 104 , 106 ) it should be readily apparent that by transposing the kernel 90° the filter will perform equally well in locating horizontal image features (as may be used for systems with vertical placement of the objective optics 104 , 106 ) without departing from the invention.", "[0031] A mechanical range finder may require the operator to focus one of the focus rings 104 A, 106 A on a target and a linear or rotational position sensor could be used to determine the distance to target (see FIGS. 6A-6C and discussed in further detail below).", "Alternatively, a mechanical circuit may include a linear or rotary potentiometer mechanically coupled to one of the focus rings 104 A, 106 A. In an alternative embodiment, the system may accept inputs from a user regarding the distance to target.", "The input may be received through a near/far actuator or a menu selection.", "The system may be designed so the operator selects the far mode when the object being viewed is greater than 100 meters away and the operator selects the near mode when the object being viewed is less than 100 meters away.", "Distances other than 100 meters may be chosen without departing from the invention.", "The fusion night vision system may also incorporate multiple distance choices, for example close, less than 25 meters;", "mid range, 25-50 meters;", "long range, 50-100 meters;", "real long range, greater than 100 meters without departing from the invention.", "[0032] The alignment correlation circuit 410 may receive the distance to target information from the mechanical range finder 432 to establish a coarse estimate of the amount of image shift required.", "Using the coarse estimate as an initial starting point the alignment correlation circuit 410 may then compare the binary maps held within buffer memory 430 , corresponding to the location of object edges in the images produced by the first sensor 204 and the second sensor 208 , to determine a fine alignment estimate.", "The alignment correlation circuit 410 may start the comparison of the binary edge maps shifted relative to each other based on the coarse estimate and then translate them left or right until a best match is found.", "A best match may be found when the number of matching pixels within the edge maps is highest, i.e. the peak of the correlation function, for the pixel shift attempted.", "For each increment in image shift, the alignment correlation circuit 410 may calculate the corresponding value of the correlation function by summing over all pixel locations the result of performing a pixel-by-pixel logical “and”", "operation between the two binary maps under evaluation with the net result being a count of all pixel locations for which a value of one (1) is present in both binary edge maps.", "Alternatively, the alignment correlation circuit 410 may use only a central portion of the binary maps without departing from the invention.", "[0033] For the example shown in FIG. 8 , the alignment correlation circuit has determined that the image from the first sensor should be shifted left (minus) three (3) pixels relative to the image from the second sensor as indicated by the peak in the correlation function as plotted.", "It should be readily apparent to those skilled in the art that a correlation circuit based upon a logical “nor”", "operation would produce equally valid results without departing from the invention if the use of 0's and 1's within the binary edge maps were interchanged.", "[0034] The output of the alignment correlation circuit 410 may instruct the first pixel shift circuit 412 to shift the interpolated output from the first sensor 204 to the left one (1) pixel and the second pixel shift circuit 414 to shift the output from the second sensor 208 to the right two (2) pixels where the sum total shift in pixels is equal to the sum of the coarse and fine alignment estimates.", "The outputs of the pixel shift circuits 412 , 414 may be inputted into an image combiner 416 to combine the two images into a single fused image outputted to the display formatter 202 B. An image combiner 416 may be a circuit that adds or fuses, in analog or digital form, the image from the first sensor 204 with the image from the second sensor 208 or may employ a more complex circuit designed for image fusion such as the Acadia processor from Pyramid Vision.", "[0035] FIG. 6A is a schematic of a mechanical range finder, FIG. 6B is a switch state diagram, and FIG. 6C is a look up table consistent with the invention.", "Sensors SW 1 , SW 2 , for example Hall effect switches, may be located in the housing 102 adjacent a rotatable or translatable focus ring 104 A, 106 A that surrounds the objective optics 104 , 106 .", "The user can rotate or translate the focus ring 104 A, 106 A clockwise or counter-clockwise from near N to far F as the user attempts to focus on a target.", "As the focus ring 104 A, 106 A is rotated, the state of the sensors SW 1 , SW 2 may be read by a processor 620 .", "The processor 620 may be part of the low voltage power supply and controller 212 or may be part of the signal processing electronics 202 .", "A series of magnets 652 in close proximity, or a single arcuate magnet, may be coupled to the focus ring 104 A, 106 A in an arcuate path.", "The magnets 652 may be located in holes formed in the focus ring 104 A, 106 A. The location and spacing of the sensors relative to the magnets may depend on the angular rotation of the focus ring 104 A, 106 A from near N to far F. The location of the sensors SW 1 , SW 2 and the magnet(s) 652 may also be swapped without departing from the invention.", "[0036] FIG. 6C is a coarse parallax correction look-up table consistent with the invention.", "As the distance to target changes, the processor 620 may provide the corresponding estimate for coarse alignment in pixels of image shift to the alignment correlation circuit 410 .", "For example, when a target is approximately 75 meters away, the range finder 432 may send a signal to the alignment correlation circuit 410 that the images need to be shifted by a nominal amount of five (5) pixels in total.", "[0037] FIG. 7A is an image of a scene from the first sensor of the fusion night vision system 100 ;", "FIG. 7D is an image of the same scene from the second sensor of the fusion night vision system 100 ;", "and FIG. 7G is a fused/combined image viewable through the eyepiece 108 of the fusion night vision system 100 .", "The fused image provides more scene information than either of the individual images.", "In FIG. 7D , an antenna 702 is viewable with the second sensor 208 but not with the first sensor 204 and in the FIG. 7A the doorway of the trailer is viewable with the first sensor 204 but not the second sensor 208 .", "FIG. 7G shows the fused image in which the antenna 702 and the trailer doorway 704 are viewable.", "FIG. 7B shows the output of the horizontal/vertical feature filter circuit 408 A and FIG. 7C shows the output of the binary filter 408 B for the first sensor 204 .", "FIG. 7E shows the output of the horizontal/vertical feature filter circuit 408 A and FIG. 7F shows the output of the binary filter 408 B for the second sensor 208 .", "[0038] Certain embodiments of the invention can be implemented in hardware, software, firmware, or a combination thereof.", "In one embodiment, the parallax correction circuit is implemented in software or firmware that is stored in a memory and that is executable by a suitable instruction execution system.", "If implemented in hardware, as in an alternative embodiment, the circuits can be implemented with any or a combination of the following technologies, which are well known in the art: a discrete logic circuit(s) having logic gates for implementing logic functions upon data signals, an application specific integrated circuit (ASIC) having appropriate combinational logic gates, a programmable logic device (PLD), a field programmable gate array (FPGA), etc.", "[0039] FIG. 9 is a fusion alignment flow chart consistent with an embodiment of the invention.", "The first sensor acquires data representative of a scene at block 902 and the second sensor acquires data representative of the same scene at block 912 .", "The output of the first sensor is received by the first shift pixel circuit at block 920 and the horizontal/vertical feature filter circuit at block 904 and output of the second sensor is received by the second shift pixel circuit at block 922 and the horizontal/vertical feature filter circuit at block 914 .", "The horizontal/vertical feature filter circuit filters the data from each sensor to define edges and then outputs the data from the first sensor to the binary filter at block 906 and the data from the second sensor to the binary filter at block 916 .", "The binary filter converts each pixel to one of two unique values (e.g. 0 and 1).", "The outputs of the binary filter circuits (binary edge maps) are then inputted to the buffer memory at block 908 .", "The alignment correlation circuit at block 909 may then start the comparison by translating the binary edge maps temporarily stored within the buffer memory and corresponding to images from the first and the second sensors left and right about the coarse align position until a best match is found.", "The alignment correlation circuit then instructs the pixel shift circuits how many pixels to move the image and in which direction at block 920 , 922 .", "After the first and second images are shifted (if necessary), the images are combined in a combiner at block 910 and outputted to the display formatter.", "[0040] Although several embodiments of the invention have been described in detail herein, the invention is not limited hereto.", "It will be appreciated by those having ordinary skill in the art that various modifications can be made without materially departing from the novel and advantageous teachings of the invention.", "Accordingly, the embodiments disclosed herein are by way of example.", "It is to be understood that the scope of the invention is not to be limited thereby." ]
FIELD OF THE DISCLOSURE [0001] This disclosure relates generally to mattresses and, more specifically, to a modular mattress system designed for ease of manufacturing and shipping by the manufacturer, and for ease of feature selection, handling and assembly or installation by the consumer. BACKGROUND OF THE DISCLOSURE [0002] In the retail mattress market, there are various ways in which a consumer may purchase a mattress and box spring set, referred to hereafter as a mattress set. A mattress set may be purchased, for example, by visiting a retail store, by placing a telephone order to a retailer, or by placing an order over an internet website. In each of these purchasing instances, the specific size of the mattress set, and possibly the firmness of the mattress set and the type of padding layer covering the mattress, may be specified by the consumer. If the mattress set is being delivered to and assembled at the consumer's living space, then additional fees may be charged for such services. These may be flat fees or may vary based on, e.g., the size of the mattress set being delivered and distance from the warehouse to the consumer's living space. [0003] The mattress industry promotes certain standard bed sizes, as follows: Crib size is 28 inches wide by 52 inches long; Twin size is 38 inches by 75 inches; Full (“Double”) size is 53 inches by 75 inches; Queen size is 60 inches by 80 inches; King size is 76 inches by 80 inches; and California King size is 72 inches by 84 inches. Mattress firmness may typically be specified as soft, medium, or firm, with other firmness options available depending upon the manufacturer. Along with industry-standard regular mattress padding layers, manufacturers may also offer other options such as a “pillow top” surface consisting of a two to four-inch-thick cushion of soft material, or a “memory foam” surface designed to minimize stress that a mattress will exert upon the sleeper's body. [0004] For mattress sets ordered via the internet, the consumer may specify the size, firmness, and padding layer covering the mattress by choosing these features using their computer in a point-and-click manner with their mouse devices. Other features, such as fabric pattern, frame type, etc., may be available for the consumer to choose as well. Additionally, the consumer may need to input other information such as the address to which the mattress set will be delivered, payment information, and other delivery and assembly particulars (e.g., major intersections, acceptable delivery times, stairway configurations, elevator dimensions, or other potential physical obstacles for delivery personnel to consider). [0005] Following mattress set specification and an online purchase transaction, the mattress set may then be shipped from the website's local warehouse via truck to the consumer's house and assembled by the delivery crew. Each component of the mattress set, i.e., a mattress and a box spring, is typically wrapped in a plastic sheathing, which will be removed by the delivery crew upon installation. The disposal of the consumer's old mattress set is often subject to the purchase agreement. Some companies may offer to discard the old mattress sets (for a disposal fee or free of charge) or move them to another location within the customer's living space. Other times, the consumer may be expected to dispose of their old set. [0006] For mattress sets purchased via telephone, typically only the specific size and possibly the firmness of the mattress and style of the mattress padding layer may be specified by the consumer. These purchases usually occur on the local level, where consumers call either a local telephone number or perhaps a toll-free number and a local company delivers and assembles the mattress set. [0007] For those mattress sets purchased directly (in person) from a retailer, the specific size, the firmness of the mattress set, and the style of the mattress padding layer may be specified by the consumer. The consumer interacts with the sales staff to determine exactly which features are important to him or her in order to make an informed decision, and at the time of purchase, arrangements are typically made for home delivery and assembly. [0008] Consumers who purchase mattress sets hope to get many years of service out of them. In order to prolong the useable life of a mattress, the industry suggests rotating and flipping the mattress on a regular basis. This is done to promote reasonable wear patterns since most mattresses are manufactured using series of tightly grouped coil springs. These springs can fatigue or develop a “memory” if they are subject to the same bodily forces on a regular basis, as may occur from a consumer sleeping in the same position each night. The bigger the mattress set, the more difficult it becomes for the consumer to flip the mattress. For many mattress sets larger than twin size, it can be difficult, if not impossible, for one person (particularly an elderly person) to flip the mattress. In many instances, consumers will forego this industry-recommended flipping procedure and thus may reduce the useable life of their mattress. Continued use of a mattress past its useful life frequently leads to discomfort, poor sleep, and back problems. [0009] When a mattress set is installed in a consumer's living space, that may be the last time that the consumer has help available to handle their mattress set. The consumer may be incapable of moving the mattress in order to flip it, to clean under the bed, or to rearrange the layout of their living space. [0010] Over its useable life, the fabric cover of a mattress may also become stained or otherwise contaminated and may need to be cleaned. Since mattresses are rather thick and soft, they have a tendency to absorb any applied cleaning solution. This absorption may make difficult the thorough drying of the surface of the mattress. Stain removers are also not very effective. Machine washing or dry cleaning of just the fabric cover of a mattress would be preferable, but is not possible with a conventional mattress, as the fabric cover is not removable. The manner in which these and other shortcomings of conventional mattresses are overcome is described in the following Summary of the Disclosure and Detailed Description of the Preferred Embodiments. SUMMARY OF THE DISCLOSURE [0011] A modular mattress system is disclosed in which the spring structure of a typical marketplace coil spring mattress is divided into segments of grouped coil springs, hereafter referenced as mattress blocks, that may be tightly compressed, shipped to a consumer via common delivery channels in packaging that can be received by a consumer, brought into their living space, and easily assembled by the consumer without assistance. The modular mattress system of the present disclosure, when assembled, has the same external appearance as a conventional mattress and offers a premium sleep surface comparable or superior to most conventional coil spring mattresses. [0012] A modular mattress system includes mattress blocks that have the same vertical cross-sectional appearance as that of a standard coil spring mattress. Each mattress block includes a plurality of rows and columns of resilient coil springs, which coil springs may or may not be individually wrapped. The rectangular array of springs is contained in a thin shell which shell may, by way of example only, be a woven or non-woven fabric. Mattress blocks may be manufactured in various sizes that, when assembled together and secured in an appropriate fabric cover with a selected layering of foam material above the mattress blocks, create a standard size mattress such as a Twin size mattress, Queen size mattress, or other size mattress. [0013] Due to their coil spring structure and thin shell, all the mattress blocks necessary for assembly of a mattress of a given standard size may be compressed, such as in an air evacuable storage bag or similar packaging material using, for example, an industrial vacuum cleaner. [0014] A fabric mattress cover may be provided with each modular mattress system. This fabric mattress cover may include two fabric layers (one top and one bottom) with each layer having the same length and width as that of the associated final mattress size. These mattress cover pieces may be joined together with other fabric to cover the sides of the final mattress configuration. A selectively securable seam, such as a zipper, may be provided preferably along three sides of the bottom layer of the mattress cover in order to allow access to the interior of the fabric mattress cover for insertion or removal of the mattress blocks. It is recognized that other securement means, such as Velcro™ hook-and-loop fasteners, snaps, or buttons, may alternatively be used to provide a selectively securable seam to open or close the fabric mattress cover. For assembly, mattress blocks are arranged in an open mattress cover. During assembly by the consumer, the mattress cover is preferably upside down, with the top layer spread out on the floor or box spring. If desired, one or more foam (or similar) layers of padding is supplied to cover the arranged mattress blocks. Once the internal structure of the mattress system is arranged according to the consumer's final desired configuration, the mattress cover is closed and the mattress is ready to be turned right side up, with the selectively securable seam concealed from sight. [0015] Mattress blocks may be provided in various degrees of firmness, including but not limited to soft, medium, and hard. In a coil spring mattress, the stiffness of the coils is a significant factor in determining the final firmness experienced by the consumer. The stiffer the coils, the firmer the mattress will feel to the consumer. The firmness of mattress blocks employed in a mattress of the present disclosure may be specified by the consumer, and indicia and/or color coding of the exterior of the mattress blocks may be used to differentiate mattress blocks of different firmness. Though each individual mattress block will be of uniform firmness throughout the entire block, blocks of different firmness may be assembled together in the final mattress configuration to achieve a mattress having regions of varying firmness. For example, the consumer may choose a different firmness for the mattress block supporting the back than for the mattress block supporting the head, or for different sides of the mattress, so sleepers having different stiffness preferences can share the same mattress while satisfying their individual, distinct mattress support preferences. [0016] The firmness of the modular mattress system at any point, as felt by the consumer, is a combination of the firmness of not only the mattress blocks, but also of the firmness of its other components. Thus, foam pad firmness and fabric mattress cover firmness may also factor into the overall firmness of the modular mattress system. BRIEF DESCRIPTION OF THE DRAWINGS [0017] FIG. 1 is a perspective view of a mattress block, including an array of resilient coil springs; [0018] FIG. 2 is a top plan view of a mattress block, partially cut away, exposing an array of resilient coil springs; [0019] FIG. 3 is a side cut away view of a mattress block, exposing a plurality of resilient coil springs; [0020] FIG. 4 is a side cut away view of a single resilient coil spring and its cloth wrapping; [0021] FIG. 5 is a perspective view of an open fabric mattress cover and its selectively securable seam; [0022] FIG. 6 is a perspective view of a foam pad of a modular mattress system of the present disclosure; [0023] FIG. 7 is a perspective view of a plurality of mattress blocks of a modular mattress system of the present disclosure; [0024] FIG. 8 is a perspective view of a foam pad and a plurality of mattress blocks, as installed in an unsecured fabric mattress cover; [0025] FIG. 9 is a perspective view of an underside of a modular mattress system, showing a bottom layer of the fabric mattress cover of FIG. 8 after securement of the bottom layer of the fabric mattress cover over the plurality of mattress blocks; [0026] FIG. 10 is a perspective view of a modular mattress system, as set into its final assembled position, with a selectively securable seam of the fabric mattress cover hidden underneath; [0027] FIG. 11 is a perspective view of a fabric mattress cover with its selectively securable seam unsecured, and its bottom layer displayed in the foreground; [0028] FIG. 12 is a perspective view of a foam pad; [0029] FIG. 13 is a perspective view of a plurality of mattress blocks; [0030] FIG. 14 is a perspective view of a foam pad and a plurality of mattress blocks, as placed directly on the exposed bottom layer of the unsecured fabric mattress cover of FIG. 11 ; [0031] FIG. 15 is a perspective view of the modular mattress system shown in FIG. 14 , after securement of the selectively securable seam of the fabric mattress cover; [0032] FIG. 16 is a comparative illustration of the standard mattress sizes (in inches) produced for the retail mattress industry; [0033] FIG. 17 is a top plan view of a modular mattress system; with fabric mattress cover, foam pad, and mattress block covering material cut away, exposing arrays of resilient coil springs of each mattress block; [0034] FIG. 18 is a top plan view of a modular mattress system; with fabric mattress cover, foam pad, and mattress block covering material cut away, exposing arrays of resilient coil springs of each mattress block arranged in a different configuration from the configuration of mattress blocks shown in FIG. 17 ; [0035] FIG. 19 is a perspective view, partially cut away, of a plurality of mattress blocks, as installed in an unsecured fabric mattress cover, exposing a single coil spring within one of the mattress blocks, and portion of a foam pad; [0036] FIG. 20 is a perspective view of an open fabric mattress cover; [0037] FIG. 21 is a perspective view of a washer and; [0038] FIG. 22 is a flowchart of a process of the present disclosure for ordering, packaging, and distributing a modular mattress system; [0039] FIG. 23 is a perspective View of a plurality of mattress blocks, a foam pad, and a fabric mattress cover for a modular mattress system of the present disclosure; [0040] FIG. 24 is a perspective view of a plurality of mattress blocks, a foam pad, and a fabric mattress cover, as gathered together in preparation for compressing and shipping; [0041] FIG. 25 is a perspective view of the plurality of mattress blocks, the foam pad, and the fabric mattress cover of FIG. 24 , in a stacked arrangement, along with an air evacuable bag large enough to enclose these modular mattress system components; [0042] FIG. 26 is a perspective view of the stacked plurality of mattress blocks, foam pad, and fabric mattress cover enclosed within the air evacuable bag of FIG. 25 , with the air evacuable bag being attached to an industrial vacuum cleaner; [0043] FIG. 27 is perspective view of a compressed plurality of mattress blocks, foam pad, and fabric mattress cover enclosed within an air evacuable bag, from which air has been removed by an industrial vacuum cleaner; and [0044] FIG. 28 is a flowchart of a possible life cycle of a modular mattress system of the present disclosure in which components of the modular mattress system are compressed within an air evacuable bag and shipped from a manufacturer to a consumer, and after the useful life of the modular mattress system, the components are recompressed into the air evacuable bag for disposal in the trash, facilitating transportation and minimizing the space ultimately occupied by the modular mattress system in a landfill. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0045] Having reference to the drawings, where like reference numbers comprise like elements, there is shown in FIG. 1 and FIG. 2 a mattress block, generally denoted by reference number 10 . The mattress block 10 includes a covering material 12 which encloses an array of resilient coil springs 14 , with each coil spring 14 preferably surrounded by a compressible cloth wrapping 16 . FIG. 3 shows a cross-sectional view of the mattress block 10 , including an array of coil springs 14 , each surrounded by a cloth wrapping 16 , all enclosed within covering material 12 . FIG. 4 shows a cross-sectional view of a typical coil spring 14 surrounded by its cloth wrapping 16 . [0046] Each coil spring 14 , with its cloth wrapping 16 , is designed to move independently of any other coil spring 14 . The coil springs 14 are tightly packed adjacent to one another within covering material 12 such that no gap or crease is felt between rows or columns of the coil springs 14 . For any given size of mattress block 10 , the smaller the diameter of each coil spring 14 , the more coil springs 14 may be packed into the mattress block 10 . Generally, in mattress design, the more springs that can be inserted into a given size mattress, the better that mattress may be in conforming to the body shape of the sleeper. The same holds true for the mattress block 10 design of the present disclosure. [0047] FIGS. 5-10 show an embodiment of a modular mattress system 22 of the disclosure, which may include a fabric mattress cover 24 , a foam pad 28 , and a plurality of mattress blocks 10 . FIG. 5 shows a fabric mattress cover 24 which may include a top layer 24 A, a bottom layer 24 B, and at least one sidewall 24 C. A selectively securable seam 26 , such as a zipper, is provided along the intersection of the bottom layer 24 B and at least one sidewall 24 C of the fabric mattress cover 24 , in order to allow access to its interior space for inserting and removing mattress blocks 10 (see FIG. 2C ). FIG. 6 shows a foam pad 28 which may be inserted into the open fabric mattress cover 24 of FIG. 5 to create the first layer of padding experienced by the consumer, which may lie underneath the top layer 24 A of the fabric mattress cover 24 . [0048] The second layer of the mattress interior, within the fabric mattress cover 24 , may be created by a plurality of mattress blocks 10 , as shown in FIGS. 7 and 8 . FIG. 8 shows both the foam pad 28 and the mattress blocks 10 installed in an open fabric mattress cover 24 . FIG. 9 shows the fabric mattress cover 24 secured in the closed position (enclosing the foam pad 28 and the mattress blocks 10 ) through the use of the selectively securable seam 26 . Upon securement of the selectively securable seam 26 , the modular mattress system 22 may be flipped over as shown in FIG. 2F , such that the selectively securable seam 26 is hidden from view, underneath the modular mattress system 22 , as shown in FIG. 2G . [0049] Advantageously, not only is there no gap or crease felt between rows or columns of the coil springs 14 of a given mattress block 10 , but because the covering material 12 is sufficiently thin, no gap or crease is created or felt between adjacent mattress blocks 10 . The only way a person lying on the mattress of the modular mattress system 22 might feel that the mattress includes different mattress blocks 10 would be in situations where mattress blocks 10 of different firmness are arranged in the modular mattress system 22 , as described below. [0050] FIGS. 11-15 show an alternative way in which a modular mattress system 22 may be assembled, without the need to flip the mattress over upon completion of assembly. FIG. 11 shows an open fabric mattress cover 24 . FIG. 12 and FIG. 13 show the insertable components, a foam pad 28 and mattress blocks 10 , respectively. FIG. 14 shows the mattress blocks 10 abutting the top layer 24 A of the fabric mattress cover 24 , and the foam pad 28 abutting the mattress blocks 10 . Also visible is the selectively securable seam 26 . FIG. 15 shows the modular mattress system 22 , after the fabric mattress cover 24 has been pulled downward over the foam pad 28 and the mattress blocks 10 (see FIG. 3D ) and secured with the selectively securable seam 26 . This selectively securable seam 26 is hidden away from view along the edge of the bottom layer 24 B of the fabric mattress cover 24 of the modular mattress system 22 . [0051] FIG. 16 shows a comparison of the relative sizes of mattresses which the mattress industry promotes as standard. Mattress sizes 29 range from a Crib size of 28 inches wide by 52 inches on the small end to a King size of 76 inches wide by 80 inches long. The main component of the modular mattress system 22 of this disclosure is the mattress block 10 . Mattress blocks 10 may be combined within the modular mattress system 22 in order to create the standard sizes as shown in FIG. 4 , as well as other non-standard mattress sizes, as necessary. Certain standard mattress sizes 29 may be replicated using a plurality of mattress blocks 10 of the same size or of varying sizes. The number of mattress blocks 10 needed and their size may best be determined by the manufacturer, in order to balance the comfort of the sleeper with the cost or ease of manufacturing and supplying the mattress blocks 10 , for example. [0052] A consumer may purchase a conventional coil spring mattress with a given firmness, such as soft or firm, that is uniform throughout the mattress. The firmness is typically consistent across the entire mattress, from the area where a consumer's head would rest down through the area where their feet would rest. However, a consumer may purchase a modular mattress system 22 of the present disclosure, in which they advantageously may specify variable firmness levels of mattress blocks 10 , and/or foam pad 28 layers. [0053] FIGS. 17 and 18 show a top view of mattress blocks 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 positioned in a modular mattress system 22 . Any foam pad 28 that may have been covering the mattress blocks 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 has been removed, along with the fabric mattress cover 24 . FIG. 17 shows a modular mattress system 22 in which mattress blocks 30 , 32 , 34 , 36 are each made of an array of coil springs 14 having a first stiffness, corresponding, for instance, to a desired firmness. Also shown are mattress blocks 38 , 40 , 42 , 44 , each made of an array of coil springs 14 having a second stiffness, for example, to provide relatively less support. Correspondingly, the consumer who sleeps on this modular mattress system 22 may have a different firmness supporting their head and back as compared to the firmness supporting the lower portion of their body. [0054] Similarly, FIG. 18 shows a modular mattress system 22 in which mattress blocks 30 , 32 , 34 , 36 are each made of an array of coil springs 14 having a first stiffness, corresponding, for instance, to a desired firmness. Also shown are mattress blocks 38 , 40 , 42 , 44 , each made of an array of coil springs 14 having a second stiffness, for example, to provide relatively less support. Thus, the person who sleeps on the left side (as viewed from above) of this modular mattress system 22 may have one consistent firmness (more firm) supporting their entire body as compared to the person who sleeps on the right side, who will have a different firmness (less firm) supporting their entire body. [0055] Another way in which the firmness of the sleeping surface of the modular mattress system 22 may be varied is in the selection of the foam pad 28 that may be used to cover the mattress blocks 10 . Consumers may specify that foam pads 28 of different uniform firmness be included in the modular mattress system 22 that they purchase. For example, a consumer may specify that all of the mattress blocks 10 used in their modular mattress system 22 be of the same firmness, but that they be given two foam pads 28 with their order. One foam pad 28 may satisfy the firmness requirement of the person who sleeps on the right side of the bed and covers the mattress blocks 10 that support that person; and another foam pad 28 may satisfy the firmness requirement of a second person who sleeps on the left side of the bed and covers their supporting mattress blocks 10 . [0056] The firmness felt by a person at any given point on the surface of the modular mattress system 22 is primarily a combination of the stiffness of the foam pad 28 at that point, along with the stiffness of the mattress block 10 and the stiffness of the fabric mattress cover 24 at that point, given by the equation: [0000] 1 /k foam pad +1 /k mattress block +1 /k fabric mattress cover =1 /k total [0057] In this equation, the constant “k” represents the stiffness of the foam pad 28 , the mattress block 10 , the fabric mattress cover 24 , or the total, i.e. combined, stiffness. Therefore, the firmness felt by the consumer at any point on the modular mattress system 22 may be achieved by varying the firmness of the foam pad 28 , by varying the firmness of the mattress blocks 10 , by varying the firmness of the fabric mattress cover 24 , or by varying some combination of these components 28 , 10 , 24 . For example, a desired firmness for the area that supports a person's head may be achieved through the use of a “firm” mattress block(s) 10 and a “soft” foam pad 28 , or similarly, by using a “soft” mattress block 10 along with a “firm” foam pad 28 covering it. Similar firmnesses may be achieved in different ways. Manufacturers could use this principle to help them balance their inventories of foam pads 28 , mattress blocks 10 , and fabric mattress covers 24 , as modular mattress systems 22 are specified and ordered by consumers. [0058] Consumers may be offered the option to order modular mattress system 22 components, such as mattress blocks 10 , foam pads 28 , and fabric mattress covers 24 , as replacement parts for components that they may have been damaged, destroyed or lost. The purchase of replacement component parts has not been practical for damaged conventional coil spring mattresses, so they are often discarded in their entirety, and new mattress sets purchased. With the modular mattress system 22 of the present disclosure, consumers may also be given an opportunity to purchase replacement parts such as foam pads 28 or individual mattress blocks 10 if they desire to change the firmness of their modular mattress system 22 , for example, if they are pregnant or suffered a particular bodily injury such that they would benefit from a change in the firmness of a portion of their mattress. [0059] An important procedure for extending the life of a conventional inner coil spring mattress is the industry-recommended act of turning the mattress over at manufacturer-recommended intervals. In other words, flipping the mattress every six months, for example, may minimize the development of wear patterns in the array of resilient coil springs 14 . For the modular mattress system 22 of the present disclosure, this procedure may be simplified. There may be no more struggling on the part of an individual consumer to lift and turn over their one-piece mattress. Since the modular mattress system 22 includes a plurality of mattress blocks 10 of separate arrays of coil springs 14 , when flipping of the mattress is desired, the consumer need only open the selectively securable seam 26 of the fabric mattress cover 24 , remove, flip, and replace each individual mattress block 10 , then re-secure the selectively securable seam 26 . [0060] As seen again in FIGS. 17 and 18 , all mattress blocks 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 are exposed upon opening of the fabric mattress cover 24 and any extra layers of foam pad 28 . The consumer then simply flips each mattress block 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 over and then reassembles the fabric mattress cover 24 and any layers of foam pad 28 that were temporarily removed to gain access to the mattress blocks 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 . [0061] As an aid to the consumer, as well as manufacturing and warehouse personnel, each mattress block 10 may display a label, tag, or some other sort of indicia which identifies characteristics such as firmness, size, date of manufacture, country of origin, etc. Also present may be information regarding the manufacturer-recommended procedure for flipping the mattress blocks 10 at certain intervals. Similar information may be displayed on other modular mattress system 22 components such as foam pads 28 and fabric mattress covers 24 . [0062] Another important feature which distinguishes the modular mattress system 22 disclosed herein from a conventional mattress is shown in FIGS. 19-22 . FIG. 19 shows the modular mattress system 22 with the selectively securable seam 26 of its fabric mattress cover 24 unsecured, exposing a plurality of mattress blocks 10 . FIG. 20 shows the fabric mattress cover 24 alone, after the mattress blocks 10 and any foam pad 28 have been removed. As represented in FIG. 21 , a consumer may place this fabric mattress cover 24 directly into a residential or commercial washer 25 and dryer 27 , for cleaning and drying purposes. The fabric mattress cover 24 is designed to withstand repeated cleaning and drying cycles. In order for a consumer to clean and dry a conventional mattress, a cleaning solution would need to be applied to the mattress and the subsequent wet area would need to be either air dried or, perhaps, fan dried. This procedure may be considered tedious, especially for an entire mattress. The ability for this fabric mattress cover 24 to be so easily removed from the mattress system 22 so as to be independently cleaned and dried may be considered especially desirable for incontinent individuals, those who provide assistance to them, and parents of children who are bedwetters. [0063] Turning to FIG. 22 , various methods of specifying, ordering, and distributing a modular mattress system 22 are also within the scope of the present disclosure. A consumer may specify and order a modular mattress system 22 by going to a retail store 60 , placing a telephone call 62 , or by using the internet 64 . In all cases, the consumer may choose among such modular mattress system 22 characteristics as size, firmness of individual mattress blocks 10 , fabric mattress cover 24 exterior color, fabric mattress cover 24 exterior pattern, type of foam pad 28 used over or under the mattress blocks 10 , type of selectively securable seam 26 used in securing the fabric mattress cover 24 , etc. At the same time the consumer may specify such delivery details as the method of delivery and the timeframe. When ordering a conventional coil spring mattress, consumers may be able to choose only a few characteristics such as size, overall firmness, type of foam padding used for the mattress and the delivery details. Regarding a conventional mattress set delivery, the consumer may also be concerned with the extra step of having delivery personnel come into their residence and assemble the mattress set, whereas with the mattress system 22 of the present disclosure, with its comparatively easy assembly, no such extra step is required. [0064] FIG. 22 is a flow-chart diagram of a ordering, packaging, and distributing a modular mattress system 22 . A consumer may order their new modular mattress system 22 via a retail store 60 , the telephone 62 , or the internet 64 . In each case, the consumer's order may be entered into an order processing computer or CPU 66 , which may forward information regarding the components necessary to build the specific modular mattress system 22 ordered, to the appropriate warehouse personnel for fulfillment. The order picker 68 may then obtain the warehouse stocked components necessary to fulfill the specified order. Each of these stocked components may be stored in different but convenient supplies, such as a mattress block supply 70 , a mattress pad supply 72 , and a fabric mattress cover supply 74 . When all components have been gathered together, personnel may take an appropriately-sized air evacuable bag 78 and place the components into this bag 78 . They may then proceed to use an industrial vacuum source 78 to remove air from the bag 78 in order to compress the contents into a shippable size. It will be appreciated that all or part of the order-taking, packaging, and distributing process may be automated, such as by use of conveyor or robotic technology. [0065] Individual components of the modular mattress system 22 , such as mattress blocks 10 , foam pads 28 , and fabric mattress covers 24 , occupy less volume than complete coil spring mattress sets and are considerably lighter in weight as well. The compact size of the components of the modular mattress system 22 should be beneficial in reducing the number of personnel, and the size and complexity of the storage and handling equipment needed along the entire supply chain, as compared to that of the conventional coil spring mattress. Fewer manufacturing personnel, warehouse personnel, retail stocking personnel, and delivery personnel, along with the need for less rugged, and thus cheaper, storage and handling equipment may increase the profit margins for those companies along the modular mattress system 22 supply chain. [0066] Since modular mattress systems 22 may require fewer and less expensive resources to stock, handle, and ship them, as compared to the resources needed for conventional coil spring mattress sets, more companies may be interested in selling modular mattress systems 22 . These companies may include those specializing in internet sales 60 , retail stores 62 , and catalog merchandisers specializing in telephone sales 64 . [0067] Since the modular mattress system 22 may include mattress blocks 10 of arrays of resilient coil springs 14 , along with a fabric mattress cover 24 and a foam pad 28 , all of these components are compressible when surrounded by an appropriately-sized air evacuable bag 78 and air is removed from the bag 78 . The bulky nature of a conventional coil spring mattress precludes this method of vacuum packaging for ease of shipping. As indicated in FIG. 22 , after air is removed from the air evacuable bag 78 and the contents are compressed, the bag 78 may then be placed into an appropriately-sized shipping container 80 , such as a cardboard box. This box may then be sealed, staged for shipment, and then shipped to the consumer via selected delivery channels. Since the shipping container 80 may be of a manageable size and weight, the consumer is able without assistance to receive the shipment, bring the shipping container 80 into his or her residence, and unpack the air evacuable bag 78 . The consumer may then proceed to open the air evacuable bag 78 according to the instructions enclosed. When the air evacuable bag 78 is opened, the compressed contents of the bag 78 will expand back to their original specifications, and will be ready for assembly into the modular mattress system 22 . Even when expanded, the mattress blocks 10 and other components of the mattress system 22 are sufficiently small and manageable for the individual to move the mattress to any desired location before assembly, avoiding the problems associated with negotiating conventional mattresses through corridors, around tight corners, up or down stairways, or into elevators with low ceilings. [0068] For retail store 60 transactions, consumers may opt to purchase a modular mattress system 22 and transport it home by themselves. To transport a conventional coil spring mattress set typically requires at least two people to place the mattress set into a vehicle large enough to contain it, or in many instances, to secure the mattress set on top of the vehicle, exposing the mattress to outside elements. The bulkiness of the mattress set, whether inside or on top of the vehicle, may obstruct the mirrors and windows of the driver, and may distract the attention of the driver or other drivers, thus increasing risks while driving. Since a modular mattress system 22 includes components which individually occupy much less volume than complete conventional coil spring mattress sets, and are correspondingly lighter in weight; the average consumer, without assistance, may be able to pack the components of the modular mattress system 22 into their vehicle in a safe configuration, and transport them home without incident. The mattress systems of the present disclosure occupy so little space when compressed for transport that a number of the mattress systems 22 may be transported inside a single compact size vehicle. [0069] The vacuum packaging procedure for the components of a sample modular mattress system 22 is shown in FIGS. 23-27 . FIG. 23 shows the components as a plurality of mattress blocks 10 , along with a fabric mattress cover 24 , and a foam pad 28 . FIG. 24 shows these components 10 , 24 , 28 gathered together and then reoriented (see FIG. 25 ) into a vertical stacked arrangement, with the appropriately-sized air evacuable bag 78 to enclose them located adjacently. FIG. 26 shows the vertically stacked components 10 , 24 , 28 enclosed within the air evacuable bag 78 , with this air evacuable bag 78 attached to an industrial vacuum source 79 . FIG. 27 shows the air evacuable bag 78 after air has been removed from it, and it has been disconnected from the vacuum source 78 , with its contents compressed into a shippable size. Within this air evacuable bag 78 is the compressed modular mattress system 22 , which is ready to place into a shipping container 80 and ship 82 to the consumer 84 . [0070] FIG. 28 represents a potential life cycle for the modular mattress system 22 as vacuum packaged in an air evacuable bag 78 . For this particular sample modular mattress system 22 , it may be shipped from the manufacturer 86 to the storage warehouse 88 in an air evacuable bag 78 , and stored in the warehouse 88 in that manner. It may then be pulled from the shelves of the warehouse 88 and shipped to a consumer 90 . The consumer 90 may unpack, assemble, and use the modular mattress system 22 at their residence for its useful lifespan, and then the consumer 90 may disassemble the mattress into its components and place the components back into the air evacuable bag 78 in which they originally came (or obtain a replacement air evacuable bag 78 if the original has been damaged, disposed of, or misplaced). The consumer 90 may evacuate the air within the air evacuable bag 78 once more (with their own vacuum cleaner) and place the air evacuable bag 78 into the trash 92 . The air evacuable bag 78 containing the compressed modular mattress system 22 may then be delivered to the landfill 94 , advantageously occupying substantially less space than a conventional mattress. [0071] While various embodiments of modular mattress systems 22 have been described herein, it is recognized that this disclosure is not limited to these embodiments. Variations may be made thereto which are still within the scope of the appended claims.
A modular mattress system having at least one mattress block which includes an array of resilient coil springs, along with a foam pad, and a washable/dryable fabric mattress cover. The components of the modular mattress system are compressible into an air evacuable bag for purposes of storing, shipping, and disposal. The size, firmness, type of foam pad, pattern and color of the fabric mattress cover, and type of securable seam available for the fabric mattress cover used in the modular mattress system may be specified by the consumer. Mattress size ranges from Crib size through King size, with custom sizes available as well. Various methods of specifying, ordering, and distributing the modular mattress system are detailed. The care, maintenance, assembly and usage of the modular mattress system are discussed.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "FIELD OF THE DISCLOSURE [0001] This disclosure relates generally to mattresses and, more specifically, to a modular mattress system designed for ease of manufacturing and shipping by the manufacturer, and for ease of feature selection, handling and assembly or installation by the consumer.", "BACKGROUND OF THE DISCLOSURE [0002] In the retail mattress market, there are various ways in which a consumer may purchase a mattress and box spring set, referred to hereafter as a mattress set.", "A mattress set may be purchased, for example, by visiting a retail store, by placing a telephone order to a retailer, or by placing an order over an internet website.", "In each of these purchasing instances, the specific size of the mattress set, and possibly the firmness of the mattress set and the type of padding layer covering the mattress, may be specified by the consumer.", "If the mattress set is being delivered to and assembled at the consumer's living space, then additional fees may be charged for such services.", "These may be flat fees or may vary based on, e.g., the size of the mattress set being delivered and distance from the warehouse to the consumer's living space.", "[0003] The mattress industry promotes certain standard bed sizes, as follows: Crib size is 28 inches wide by 52 inches long;", "Twin size is 38 inches by 75 inches;", "Full (“Double”) size is 53 inches by 75 inches;", "Queen size is 60 inches by 80 inches;", "King size is 76 inches by 80 inches;", "and California King size is 72 inches by 84 inches.", "Mattress firmness may typically be specified as soft, medium, or firm, with other firmness options available depending upon the manufacturer.", "Along with industry-standard regular mattress padding layers, manufacturers may also offer other options such as a “pillow top”", "surface consisting of a two to four-inch-thick cushion of soft material, or a “memory foam”", "surface designed to minimize stress that a mattress will exert upon the sleeper's body.", "[0004] For mattress sets ordered via the internet, the consumer may specify the size, firmness, and padding layer covering the mattress by choosing these features using their computer in a point-and-click manner with their mouse devices.", "Other features, such as fabric pattern, frame type, etc.", ", may be available for the consumer to choose as well.", "Additionally, the consumer may need to input other information such as the address to which the mattress set will be delivered, payment information, and other delivery and assembly particulars (e.g., major intersections, acceptable delivery times, stairway configurations, elevator dimensions, or other potential physical obstacles for delivery personnel to consider).", "[0005] Following mattress set specification and an online purchase transaction, the mattress set may then be shipped from the website's local warehouse via truck to the consumer's house and assembled by the delivery crew.", "Each component of the mattress set, i.e., a mattress and a box spring, is typically wrapped in a plastic sheathing, which will be removed by the delivery crew upon installation.", "The disposal of the consumer's old mattress set is often subject to the purchase agreement.", "Some companies may offer to discard the old mattress sets (for a disposal fee or free of charge) or move them to another location within the customer's living space.", "Other times, the consumer may be expected to dispose of their old set.", "[0006] For mattress sets purchased via telephone, typically only the specific size and possibly the firmness of the mattress and style of the mattress padding layer may be specified by the consumer.", "These purchases usually occur on the local level, where consumers call either a local telephone number or perhaps a toll-free number and a local company delivers and assembles the mattress set.", "[0007] For those mattress sets purchased directly (in person) from a retailer, the specific size, the firmness of the mattress set, and the style of the mattress padding layer may be specified by the consumer.", "The consumer interacts with the sales staff to determine exactly which features are important to him or her in order to make an informed decision, and at the time of purchase, arrangements are typically made for home delivery and assembly.", "[0008] Consumers who purchase mattress sets hope to get many years of service out of them.", "In order to prolong the useable life of a mattress, the industry suggests rotating and flipping the mattress on a regular basis.", "This is done to promote reasonable wear patterns since most mattresses are manufactured using series of tightly grouped coil springs.", "These springs can fatigue or develop a “memory”", "if they are subject to the same bodily forces on a regular basis, as may occur from a consumer sleeping in the same position each night.", "The bigger the mattress set, the more difficult it becomes for the consumer to flip the mattress.", "For many mattress sets larger than twin size, it can be difficult, if not impossible, for one person (particularly an elderly person) to flip the mattress.", "In many instances, consumers will forego this industry-recommended flipping procedure and thus may reduce the useable life of their mattress.", "Continued use of a mattress past its useful life frequently leads to discomfort, poor sleep, and back problems.", "[0009] When a mattress set is installed in a consumer's living space, that may be the last time that the consumer has help available to handle their mattress set.", "The consumer may be incapable of moving the mattress in order to flip it, to clean under the bed, or to rearrange the layout of their living space.", "[0010] Over its useable life, the fabric cover of a mattress may also become stained or otherwise contaminated and may need to be cleaned.", "Since mattresses are rather thick and soft, they have a tendency to absorb any applied cleaning solution.", "This absorption may make difficult the thorough drying of the surface of the mattress.", "Stain removers are also not very effective.", "Machine washing or dry cleaning of just the fabric cover of a mattress would be preferable, but is not possible with a conventional mattress, as the fabric cover is not removable.", "The manner in which these and other shortcomings of conventional mattresses are overcome is described in the following Summary of the Disclosure and Detailed Description of the Preferred Embodiments.", "SUMMARY OF THE DISCLOSURE [0011] A modular mattress system is disclosed in which the spring structure of a typical marketplace coil spring mattress is divided into segments of grouped coil springs, hereafter referenced as mattress blocks, that may be tightly compressed, shipped to a consumer via common delivery channels in packaging that can be received by a consumer, brought into their living space, and easily assembled by the consumer without assistance.", "The modular mattress system of the present disclosure, when assembled, has the same external appearance as a conventional mattress and offers a premium sleep surface comparable or superior to most conventional coil spring mattresses.", "[0012] A modular mattress system includes mattress blocks that have the same vertical cross-sectional appearance as that of a standard coil spring mattress.", "Each mattress block includes a plurality of rows and columns of resilient coil springs, which coil springs may or may not be individually wrapped.", "The rectangular array of springs is contained in a thin shell which shell may, by way of example only, be a woven or non-woven fabric.", "Mattress blocks may be manufactured in various sizes that, when assembled together and secured in an appropriate fabric cover with a selected layering of foam material above the mattress blocks, create a standard size mattress such as a Twin size mattress, Queen size mattress, or other size mattress.", "[0013] Due to their coil spring structure and thin shell, all the mattress blocks necessary for assembly of a mattress of a given standard size may be compressed, such as in an air evacuable storage bag or similar packaging material using, for example, an industrial vacuum cleaner.", "[0014] A fabric mattress cover may be provided with each modular mattress system.", "This fabric mattress cover may include two fabric layers (one top and one bottom) with each layer having the same length and width as that of the associated final mattress size.", "These mattress cover pieces may be joined together with other fabric to cover the sides of the final mattress configuration.", "A selectively securable seam, such as a zipper, may be provided preferably along three sides of the bottom layer of the mattress cover in order to allow access to the interior of the fabric mattress cover for insertion or removal of the mattress blocks.", "It is recognized that other securement means, such as Velcro™ hook-and-loop fasteners, snaps, or buttons, may alternatively be used to provide a selectively securable seam to open or close the fabric mattress cover.", "For assembly, mattress blocks are arranged in an open mattress cover.", "During assembly by the consumer, the mattress cover is preferably upside down, with the top layer spread out on the floor or box spring.", "If desired, one or more foam (or similar) layers of padding is supplied to cover the arranged mattress blocks.", "Once the internal structure of the mattress system is arranged according to the consumer's final desired configuration, the mattress cover is closed and the mattress is ready to be turned right side up, with the selectively securable seam concealed from sight.", "[0015] Mattress blocks may be provided in various degrees of firmness, including but not limited to soft, medium, and hard.", "In a coil spring mattress, the stiffness of the coils is a significant factor in determining the final firmness experienced by the consumer.", "The stiffer the coils, the firmer the mattress will feel to the consumer.", "The firmness of mattress blocks employed in a mattress of the present disclosure may be specified by the consumer, and indicia and/or color coding of the exterior of the mattress blocks may be used to differentiate mattress blocks of different firmness.", "Though each individual mattress block will be of uniform firmness throughout the entire block, blocks of different firmness may be assembled together in the final mattress configuration to achieve a mattress having regions of varying firmness.", "For example, the consumer may choose a different firmness for the mattress block supporting the back than for the mattress block supporting the head, or for different sides of the mattress, so sleepers having different stiffness preferences can share the same mattress while satisfying their individual, distinct mattress support preferences.", "[0016] The firmness of the modular mattress system at any point, as felt by the consumer, is a combination of the firmness of not only the mattress blocks, but also of the firmness of its other components.", "Thus, foam pad firmness and fabric mattress cover firmness may also factor into the overall firmness of the modular mattress system.", "BRIEF DESCRIPTION OF THE DRAWINGS [0017] FIG. 1 is a perspective view of a mattress block, including an array of resilient coil springs;", "[0018] FIG. 2 is a top plan view of a mattress block, partially cut away, exposing an array of resilient coil springs;", "[0019] FIG. 3 is a side cut away view of a mattress block, exposing a plurality of resilient coil springs;", "[0020] FIG. 4 is a side cut away view of a single resilient coil spring and its cloth wrapping;", "[0021] FIG. 5 is a perspective view of an open fabric mattress cover and its selectively securable seam;", "[0022] FIG. 6 is a perspective view of a foam pad of a modular mattress system of the present disclosure;", "[0023] FIG. 7 is a perspective view of a plurality of mattress blocks of a modular mattress system of the present disclosure;", "[0024] FIG. 8 is a perspective view of a foam pad and a plurality of mattress blocks, as installed in an unsecured fabric mattress cover;", "[0025] FIG. 9 is a perspective view of an underside of a modular mattress system, showing a bottom layer of the fabric mattress cover of FIG. 8 after securement of the bottom layer of the fabric mattress cover over the plurality of mattress blocks;", "[0026] FIG. 10 is a perspective view of a modular mattress system, as set into its final assembled position, with a selectively securable seam of the fabric mattress cover hidden underneath;", "[0027] FIG. 11 is a perspective view of a fabric mattress cover with its selectively securable seam unsecured, and its bottom layer displayed in the foreground;", "[0028] FIG. 12 is a perspective view of a foam pad;", "[0029] FIG. 13 is a perspective view of a plurality of mattress blocks;", "[0030] FIG. 14 is a perspective view of a foam pad and a plurality of mattress blocks, as placed directly on the exposed bottom layer of the unsecured fabric mattress cover of FIG. 11 ;", "[0031] FIG. 15 is a perspective view of the modular mattress system shown in FIG. 14 , after securement of the selectively securable seam of the fabric mattress cover;", "[0032] FIG. 16 is a comparative illustration of the standard mattress sizes (in inches) produced for the retail mattress industry;", "[0033] FIG. 17 is a top plan view of a modular mattress system;", "with fabric mattress cover, foam pad, and mattress block covering material cut away, exposing arrays of resilient coil springs of each mattress block;", "[0034] FIG. 18 is a top plan view of a modular mattress system;", "with fabric mattress cover, foam pad, and mattress block covering material cut away, exposing arrays of resilient coil springs of each mattress block arranged in a different configuration from the configuration of mattress blocks shown in FIG. 17 ;", "[0035] FIG. 19 is a perspective view, partially cut away, of a plurality of mattress blocks, as installed in an unsecured fabric mattress cover, exposing a single coil spring within one of the mattress blocks, and portion of a foam pad;", "[0036] FIG. 20 is a perspective view of an open fabric mattress cover;", "[0037] FIG. 21 is a perspective view of a washer and;", "[0038] FIG. 22 is a flowchart of a process of the present disclosure for ordering, packaging, and distributing a modular mattress system;", "[0039] FIG. 23 is a perspective View of a plurality of mattress blocks, a foam pad, and a fabric mattress cover for a modular mattress system of the present disclosure;", "[0040] FIG. 24 is a perspective view of a plurality of mattress blocks, a foam pad, and a fabric mattress cover, as gathered together in preparation for compressing and shipping;", "[0041] FIG. 25 is a perspective view of the plurality of mattress blocks, the foam pad, and the fabric mattress cover of FIG. 24 , in a stacked arrangement, along with an air evacuable bag large enough to enclose these modular mattress system components;", "[0042] FIG. 26 is a perspective view of the stacked plurality of mattress blocks, foam pad, and fabric mattress cover enclosed within the air evacuable bag of FIG. 25 , with the air evacuable bag being attached to an industrial vacuum cleaner;", "[0043] FIG. 27 is perspective view of a compressed plurality of mattress blocks, foam pad, and fabric mattress cover enclosed within an air evacuable bag, from which air has been removed by an industrial vacuum cleaner;", "and [0044] FIG. 28 is a flowchart of a possible life cycle of a modular mattress system of the present disclosure in which components of the modular mattress system are compressed within an air evacuable bag and shipped from a manufacturer to a consumer, and after the useful life of the modular mattress system, the components are recompressed into the air evacuable bag for disposal in the trash, facilitating transportation and minimizing the space ultimately occupied by the modular mattress system in a landfill.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0045] Having reference to the drawings, where like reference numbers comprise like elements, there is shown in FIG. 1 and FIG. 2 a mattress block, generally denoted by reference number 10 .", "The mattress block 10 includes a covering material 12 which encloses an array of resilient coil springs 14 , with each coil spring 14 preferably surrounded by a compressible cloth wrapping 16 .", "FIG. 3 shows a cross-sectional view of the mattress block 10 , including an array of coil springs 14 , each surrounded by a cloth wrapping 16 , all enclosed within covering material 12 .", "FIG. 4 shows a cross-sectional view of a typical coil spring 14 surrounded by its cloth wrapping 16 .", "[0046] Each coil spring 14 , with its cloth wrapping 16 , is designed to move independently of any other coil spring 14 .", "The coil springs 14 are tightly packed adjacent to one another within covering material 12 such that no gap or crease is felt between rows or columns of the coil springs 14 .", "For any given size of mattress block 10 , the smaller the diameter of each coil spring 14 , the more coil springs 14 may be packed into the mattress block 10 .", "Generally, in mattress design, the more springs that can be inserted into a given size mattress, the better that mattress may be in conforming to the body shape of the sleeper.", "The same holds true for the mattress block 10 design of the present disclosure.", "[0047] FIGS. 5-10 show an embodiment of a modular mattress system 22 of the disclosure, which may include a fabric mattress cover 24 , a foam pad 28 , and a plurality of mattress blocks 10 .", "FIG. 5 shows a fabric mattress cover 24 which may include a top layer 24 A, a bottom layer 24 B, and at least one sidewall 24 C. A selectively securable seam 26 , such as a zipper, is provided along the intersection of the bottom layer 24 B and at least one sidewall 24 C of the fabric mattress cover 24 , in order to allow access to its interior space for inserting and removing mattress blocks 10 (see FIG. 2C ).", "FIG. 6 shows a foam pad 28 which may be inserted into the open fabric mattress cover 24 of FIG. 5 to create the first layer of padding experienced by the consumer, which may lie underneath the top layer 24 A of the fabric mattress cover 24 .", "[0048] The second layer of the mattress interior, within the fabric mattress cover 24 , may be created by a plurality of mattress blocks 10 , as shown in FIGS. 7 and 8 .", "FIG. 8 shows both the foam pad 28 and the mattress blocks 10 installed in an open fabric mattress cover 24 .", "FIG. 9 shows the fabric mattress cover 24 secured in the closed position (enclosing the foam pad 28 and the mattress blocks 10 ) through the use of the selectively securable seam 26 .", "Upon securement of the selectively securable seam 26 , the modular mattress system 22 may be flipped over as shown in FIG. 2F , such that the selectively securable seam 26 is hidden from view, underneath the modular mattress system 22 , as shown in FIG. 2G .", "[0049] Advantageously, not only is there no gap or crease felt between rows or columns of the coil springs 14 of a given mattress block 10 , but because the covering material 12 is sufficiently thin, no gap or crease is created or felt between adjacent mattress blocks 10 .", "The only way a person lying on the mattress of the modular mattress system 22 might feel that the mattress includes different mattress blocks 10 would be in situations where mattress blocks 10 of different firmness are arranged in the modular mattress system 22 , as described below.", "[0050] FIGS. 11-15 show an alternative way in which a modular mattress system 22 may be assembled, without the need to flip the mattress over upon completion of assembly.", "FIG. 11 shows an open fabric mattress cover 24 .", "FIG. 12 and FIG. 13 show the insertable components, a foam pad 28 and mattress blocks 10 , respectively.", "FIG. 14 shows the mattress blocks 10 abutting the top layer 24 A of the fabric mattress cover 24 , and the foam pad 28 abutting the mattress blocks 10 .", "Also visible is the selectively securable seam 26 .", "FIG. 15 shows the modular mattress system 22 , after the fabric mattress cover 24 has been pulled downward over the foam pad 28 and the mattress blocks 10 (see FIG. 3D ) and secured with the selectively securable seam 26 .", "This selectively securable seam 26 is hidden away from view along the edge of the bottom layer 24 B of the fabric mattress cover 24 of the modular mattress system 22 .", "[0051] FIG. 16 shows a comparison of the relative sizes of mattresses which the mattress industry promotes as standard.", "Mattress sizes 29 range from a Crib size of 28 inches wide by 52 inches on the small end to a King size of 76 inches wide by 80 inches long.", "The main component of the modular mattress system 22 of this disclosure is the mattress block 10 .", "Mattress blocks 10 may be combined within the modular mattress system 22 in order to create the standard sizes as shown in FIG. 4 , as well as other non-standard mattress sizes, as necessary.", "Certain standard mattress sizes 29 may be replicated using a plurality of mattress blocks 10 of the same size or of varying sizes.", "The number of mattress blocks 10 needed and their size may best be determined by the manufacturer, in order to balance the comfort of the sleeper with the cost or ease of manufacturing and supplying the mattress blocks 10 , for example.", "[0052] A consumer may purchase a conventional coil spring mattress with a given firmness, such as soft or firm, that is uniform throughout the mattress.", "The firmness is typically consistent across the entire mattress, from the area where a consumer's head would rest down through the area where their feet would rest.", "However, a consumer may purchase a modular mattress system 22 of the present disclosure, in which they advantageously may specify variable firmness levels of mattress blocks 10 , and/or foam pad 28 layers.", "[0053] FIGS. 17 and 18 show a top view of mattress blocks 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 positioned in a modular mattress system 22 .", "Any foam pad 28 that may have been covering the mattress blocks 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 has been removed, along with the fabric mattress cover 24 .", "FIG. 17 shows a modular mattress system 22 in which mattress blocks 30 , 32 , 34 , 36 are each made of an array of coil springs 14 having a first stiffness, corresponding, for instance, to a desired firmness.", "Also shown are mattress blocks 38 , 40 , 42 , 44 , each made of an array of coil springs 14 having a second stiffness, for example, to provide relatively less support.", "Correspondingly, the consumer who sleeps on this modular mattress system 22 may have a different firmness supporting their head and back as compared to the firmness supporting the lower portion of their body.", "[0054] Similarly, FIG. 18 shows a modular mattress system 22 in which mattress blocks 30 , 32 , 34 , 36 are each made of an array of coil springs 14 having a first stiffness, corresponding, for instance, to a desired firmness.", "Also shown are mattress blocks 38 , 40 , 42 , 44 , each made of an array of coil springs 14 having a second stiffness, for example, to provide relatively less support.", "Thus, the person who sleeps on the left side (as viewed from above) of this modular mattress system 22 may have one consistent firmness (more firm) supporting their entire body as compared to the person who sleeps on the right side, who will have a different firmness (less firm) supporting their entire body.", "[0055] Another way in which the firmness of the sleeping surface of the modular mattress system 22 may be varied is in the selection of the foam pad 28 that may be used to cover the mattress blocks 10 .", "Consumers may specify that foam pads 28 of different uniform firmness be included in the modular mattress system 22 that they purchase.", "For example, a consumer may specify that all of the mattress blocks 10 used in their modular mattress system 22 be of the same firmness, but that they be given two foam pads 28 with their order.", "One foam pad 28 may satisfy the firmness requirement of the person who sleeps on the right side of the bed and covers the mattress blocks 10 that support that person;", "and another foam pad 28 may satisfy the firmness requirement of a second person who sleeps on the left side of the bed and covers their supporting mattress blocks 10 .", "[0056] The firmness felt by a person at any given point on the surface of the modular mattress system 22 is primarily a combination of the stiffness of the foam pad 28 at that point, along with the stiffness of the mattress block 10 and the stiffness of the fabric mattress cover 24 at that point, given by the equation: [0000] 1 /k foam pad +1 /k mattress block +1 /k fabric mattress cover =1 /k total [0057] In this equation, the constant “k”", "represents the stiffness of the foam pad 28 , the mattress block 10 , the fabric mattress cover 24 , or the total, i.e. combined, stiffness.", "Therefore, the firmness felt by the consumer at any point on the modular mattress system 22 may be achieved by varying the firmness of the foam pad 28 , by varying the firmness of the mattress blocks 10 , by varying the firmness of the fabric mattress cover 24 , or by varying some combination of these components 28 , 10 , 24 .", "For example, a desired firmness for the area that supports a person's head may be achieved through the use of a “firm”", "mattress block(s) 10 and a “soft”", "foam pad 28 , or similarly, by using a “soft”", "mattress block 10 along with a “firm”", "foam pad 28 covering it.", "Similar firmnesses may be achieved in different ways.", "Manufacturers could use this principle to help them balance their inventories of foam pads 28 , mattress blocks 10 , and fabric mattress covers 24 , as modular mattress systems 22 are specified and ordered by consumers.", "[0058] Consumers may be offered the option to order modular mattress system 22 components, such as mattress blocks 10 , foam pads 28 , and fabric mattress covers 24 , as replacement parts for components that they may have been damaged, destroyed or lost.", "The purchase of replacement component parts has not been practical for damaged conventional coil spring mattresses, so they are often discarded in their entirety, and new mattress sets purchased.", "With the modular mattress system 22 of the present disclosure, consumers may also be given an opportunity to purchase replacement parts such as foam pads 28 or individual mattress blocks 10 if they desire to change the firmness of their modular mattress system 22 , for example, if they are pregnant or suffered a particular bodily injury such that they would benefit from a change in the firmness of a portion of their mattress.", "[0059] An important procedure for extending the life of a conventional inner coil spring mattress is the industry-recommended act of turning the mattress over at manufacturer-recommended intervals.", "In other words, flipping the mattress every six months, for example, may minimize the development of wear patterns in the array of resilient coil springs 14 .", "For the modular mattress system 22 of the present disclosure, this procedure may be simplified.", "There may be no more struggling on the part of an individual consumer to lift and turn over their one-piece mattress.", "Since the modular mattress system 22 includes a plurality of mattress blocks 10 of separate arrays of coil springs 14 , when flipping of the mattress is desired, the consumer need only open the selectively securable seam 26 of the fabric mattress cover 24 , remove, flip, and replace each individual mattress block 10 , then re-secure the selectively securable seam 26 .", "[0060] As seen again in FIGS. 17 and 18 , all mattress blocks 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 are exposed upon opening of the fabric mattress cover 24 and any extra layers of foam pad 28 .", "The consumer then simply flips each mattress block 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 over and then reassembles the fabric mattress cover 24 and any layers of foam pad 28 that were temporarily removed to gain access to the mattress blocks 30 , 32 , 34 , 36 , 38 , 40 , 42 , 44 .", "[0061] As an aid to the consumer, as well as manufacturing and warehouse personnel, each mattress block 10 may display a label, tag, or some other sort of indicia which identifies characteristics such as firmness, size, date of manufacture, country of origin, etc.", "Also present may be information regarding the manufacturer-recommended procedure for flipping the mattress blocks 10 at certain intervals.", "Similar information may be displayed on other modular mattress system 22 components such as foam pads 28 and fabric mattress covers 24 .", "[0062] Another important feature which distinguishes the modular mattress system 22 disclosed herein from a conventional mattress is shown in FIGS. 19-22 .", "FIG. 19 shows the modular mattress system 22 with the selectively securable seam 26 of its fabric mattress cover 24 unsecured, exposing a plurality of mattress blocks 10 .", "FIG. 20 shows the fabric mattress cover 24 alone, after the mattress blocks 10 and any foam pad 28 have been removed.", "As represented in FIG. 21 , a consumer may place this fabric mattress cover 24 directly into a residential or commercial washer 25 and dryer 27 , for cleaning and drying purposes.", "The fabric mattress cover 24 is designed to withstand repeated cleaning and drying cycles.", "In order for a consumer to clean and dry a conventional mattress, a cleaning solution would need to be applied to the mattress and the subsequent wet area would need to be either air dried or, perhaps, fan dried.", "This procedure may be considered tedious, especially for an entire mattress.", "The ability for this fabric mattress cover 24 to be so easily removed from the mattress system 22 so as to be independently cleaned and dried may be considered especially desirable for incontinent individuals, those who provide assistance to them, and parents of children who are bedwetters.", "[0063] Turning to FIG. 22 , various methods of specifying, ordering, and distributing a modular mattress system 22 are also within the scope of the present disclosure.", "A consumer may specify and order a modular mattress system 22 by going to a retail store 60 , placing a telephone call 62 , or by using the internet 64 .", "In all cases, the consumer may choose among such modular mattress system 22 characteristics as size, firmness of individual mattress blocks 10 , fabric mattress cover 24 exterior color, fabric mattress cover 24 exterior pattern, type of foam pad 28 used over or under the mattress blocks 10 , type of selectively securable seam 26 used in securing the fabric mattress cover 24 , etc.", "At the same time the consumer may specify such delivery details as the method of delivery and the timeframe.", "When ordering a conventional coil spring mattress, consumers may be able to choose only a few characteristics such as size, overall firmness, type of foam padding used for the mattress and the delivery details.", "Regarding a conventional mattress set delivery, the consumer may also be concerned with the extra step of having delivery personnel come into their residence and assemble the mattress set, whereas with the mattress system 22 of the present disclosure, with its comparatively easy assembly, no such extra step is required.", "[0064] FIG. 22 is a flow-chart diagram of a ordering, packaging, and distributing a modular mattress system 22 .", "A consumer may order their new modular mattress system 22 via a retail store 60 , the telephone 62 , or the internet 64 .", "In each case, the consumer's order may be entered into an order processing computer or CPU 66 , which may forward information regarding the components necessary to build the specific modular mattress system 22 ordered, to the appropriate warehouse personnel for fulfillment.", "The order picker 68 may then obtain the warehouse stocked components necessary to fulfill the specified order.", "Each of these stocked components may be stored in different but convenient supplies, such as a mattress block supply 70 , a mattress pad supply 72 , and a fabric mattress cover supply 74 .", "When all components have been gathered together, personnel may take an appropriately-sized air evacuable bag 78 and place the components into this bag 78 .", "They may then proceed to use an industrial vacuum source 78 to remove air from the bag 78 in order to compress the contents into a shippable size.", "It will be appreciated that all or part of the order-taking, packaging, and distributing process may be automated, such as by use of conveyor or robotic technology.", "[0065] Individual components of the modular mattress system 22 , such as mattress blocks 10 , foam pads 28 , and fabric mattress covers 24 , occupy less volume than complete coil spring mattress sets and are considerably lighter in weight as well.", "The compact size of the components of the modular mattress system 22 should be beneficial in reducing the number of personnel, and the size and complexity of the storage and handling equipment needed along the entire supply chain, as compared to that of the conventional coil spring mattress.", "Fewer manufacturing personnel, warehouse personnel, retail stocking personnel, and delivery personnel, along with the need for less rugged, and thus cheaper, storage and handling equipment may increase the profit margins for those companies along the modular mattress system 22 supply chain.", "[0066] Since modular mattress systems 22 may require fewer and less expensive resources to stock, handle, and ship them, as compared to the resources needed for conventional coil spring mattress sets, more companies may be interested in selling modular mattress systems 22 .", "These companies may include those specializing in internet sales 60 , retail stores 62 , and catalog merchandisers specializing in telephone sales 64 .", "[0067] Since the modular mattress system 22 may include mattress blocks 10 of arrays of resilient coil springs 14 , along with a fabric mattress cover 24 and a foam pad 28 , all of these components are compressible when surrounded by an appropriately-sized air evacuable bag 78 and air is removed from the bag 78 .", "The bulky nature of a conventional coil spring mattress precludes this method of vacuum packaging for ease of shipping.", "As indicated in FIG. 22 , after air is removed from the air evacuable bag 78 and the contents are compressed, the bag 78 may then be placed into an appropriately-sized shipping container 80 , such as a cardboard box.", "This box may then be sealed, staged for shipment, and then shipped to the consumer via selected delivery channels.", "Since the shipping container 80 may be of a manageable size and weight, the consumer is able without assistance to receive the shipment, bring the shipping container 80 into his or her residence, and unpack the air evacuable bag 78 .", "The consumer may then proceed to open the air evacuable bag 78 according to the instructions enclosed.", "When the air evacuable bag 78 is opened, the compressed contents of the bag 78 will expand back to their original specifications, and will be ready for assembly into the modular mattress system 22 .", "Even when expanded, the mattress blocks 10 and other components of the mattress system 22 are sufficiently small and manageable for the individual to move the mattress to any desired location before assembly, avoiding the problems associated with negotiating conventional mattresses through corridors, around tight corners, up or down stairways, or into elevators with low ceilings.", "[0068] For retail store 60 transactions, consumers may opt to purchase a modular mattress system 22 and transport it home by themselves.", "To transport a conventional coil spring mattress set typically requires at least two people to place the mattress set into a vehicle large enough to contain it, or in many instances, to secure the mattress set on top of the vehicle, exposing the mattress to outside elements.", "The bulkiness of the mattress set, whether inside or on top of the vehicle, may obstruct the mirrors and windows of the driver, and may distract the attention of the driver or other drivers, thus increasing risks while driving.", "Since a modular mattress system 22 includes components which individually occupy much less volume than complete conventional coil spring mattress sets, and are correspondingly lighter in weight;", "the average consumer, without assistance, may be able to pack the components of the modular mattress system 22 into their vehicle in a safe configuration, and transport them home without incident.", "The mattress systems of the present disclosure occupy so little space when compressed for transport that a number of the mattress systems 22 may be transported inside a single compact size vehicle.", "[0069] The vacuum packaging procedure for the components of a sample modular mattress system 22 is shown in FIGS. 23-27 .", "FIG. 23 shows the components as a plurality of mattress blocks 10 , along with a fabric mattress cover 24 , and a foam pad 28 .", "FIG. 24 shows these components 10 , 24 , 28 gathered together and then reoriented (see FIG. 25 ) into a vertical stacked arrangement, with the appropriately-sized air evacuable bag 78 to enclose them located adjacently.", "FIG. 26 shows the vertically stacked components 10 , 24 , 28 enclosed within the air evacuable bag 78 , with this air evacuable bag 78 attached to an industrial vacuum source 79 .", "FIG. 27 shows the air evacuable bag 78 after air has been removed from it, and it has been disconnected from the vacuum source 78 , with its contents compressed into a shippable size.", "Within this air evacuable bag 78 is the compressed modular mattress system 22 , which is ready to place into a shipping container 80 and ship 82 to the consumer 84 .", "[0070] FIG. 28 represents a potential life cycle for the modular mattress system 22 as vacuum packaged in an air evacuable bag 78 .", "For this particular sample modular mattress system 22 , it may be shipped from the manufacturer 86 to the storage warehouse 88 in an air evacuable bag 78 , and stored in the warehouse 88 in that manner.", "It may then be pulled from the shelves of the warehouse 88 and shipped to a consumer 90 .", "The consumer 90 may unpack, assemble, and use the modular mattress system 22 at their residence for its useful lifespan, and then the consumer 90 may disassemble the mattress into its components and place the components back into the air evacuable bag 78 in which they originally came (or obtain a replacement air evacuable bag 78 if the original has been damaged, disposed of, or misplaced).", "The consumer 90 may evacuate the air within the air evacuable bag 78 once more (with their own vacuum cleaner) and place the air evacuable bag 78 into the trash 92 .", "The air evacuable bag 78 containing the compressed modular mattress system 22 may then be delivered to the landfill 94 , advantageously occupying substantially less space than a conventional mattress.", "[0071] While various embodiments of modular mattress systems 22 have been described herein, it is recognized that this disclosure is not limited to these embodiments.", "Variations may be made thereto which are still within the scope of the appended claims." ]
CROSS-REFERENCES TO RELATED APPLICATIONS This application is a continuation of U.S. application Ser. No. 10/581,329, filed Aug. 30, 2006, now U.S. Pat. No. 7,572,322, which is hereby incorporated by reference in its entirety, and which is a National Stage filing of International Application PCT/EP2004/010036, filed Sep. 9, 2004, claiming priority to German Application No. DE 103 56 776.3, filed Dec. 2, 2003, entitled “PLASMA-TREATED SURFACES FOR ADSORPTION FILTER MATERIALS”. The application claims priority to PCT/EP2004/010036 and to German Application No DE 103 56 776.3 and both references are expressly incorporated by reference herein, in their entirety. BACKGROUND OF THE INVENTION The present invention relates to plasma-treated textile surfaces for use in adsorptive filtering materials. More particularly, the present invention relates to an adsorptive filtering material having protective function against chemical poisons, in particular chemical warfare agents and chemical noxiants, as classified and disclosed herein, in particular for the production of protective materials, such as protective suits, protective gloves, protective shoes, protective covers (for example to transport casualties) and the like, in particular for NBC deployment, and also to the aforementioned protective materials produced using this adsorptive filtering material. There are a whole series of entities which are absorbed by the skin and lead to serious physical harm. Examples include the blister agent Hd (yellow cross) and the nerve gas sarin. People liable to come into contact with such poisons have to wear a suitable protective suit or be protected against these poisons by suitable protective materials. There are in principle three types of protective suits: the air- and water-vapor-impervious protective suits which are equipped with a layer of rubber impervious to chemical poisons and which very rapidly lead to a build-up of heat; the air- and water-vapor-pervious protective suits which offer the highest wear comfort; and finally protective suits which are equipped with a membrane which allows water vapor but not the aforementioned poisons through. NBC protective clothing is thus traditionally produced either from completely impermeable systems (for example suits composed of butyl rubber) or permeable, adsorptive filtering systems based on activated carbon (in pulverulent, fibrous or spherulous form). Protective suits against chemical warfare agents that are intended for prolonged use under a wide variety of conditions must not lead to a build-up of heat for the wearer. Air-pervious materials are therefore used in the main. The air-pervious, permeable protective suits generally possess an adsorbing layer comprising activated carbon which binds the chemical poisons very durably, so that even badly contaminated suits do not pose any danger to the wearer. The great advantage of this system is that the activated carbon is accessible on the inside as well as the outside, so that poisons which have succeeded in penetrating at damaged or otherwise unproof locations are very rapidly adsorbed. However, under extreme conditions, for example when a drop of a thickened poison impinges from a considerable height onto a somewhat open location on the outer material and is able to strike through to the activated carbon, the carbon layer may locally not be up to its task for a brief period. The present invention therefore has for its object to provide an adsorptive filtering or protective material which at least substantially avoids the prior art disadvantages described above and which is especially useful for the production of NBC protective materials, such as protective suits, protective gloves, protective shoes, protective covers and the like. This object is achieved in the realm of the present invention by an adsorptive filtering material as disclosed and claimed herein. Further, advantageous refinements of the adsorptive filtering material according to the preferred embodiment of the present invention are disclosed and claimed herein. The present invention further provides for the use of the present invention's adsorptive filtering material for producing protective materials of any kind, in particular for producing protective suits, protective gloves, protective shoes and protective covers, preferably for NBC deployment, and also the thus produced protective materials of the aforementioned kind themselves. According to a first aspect of the present invention there is accordingly provided an adsorptive filtering material which provides protection against chemical poisons, in particular chemical warfare agents and chemical noxiants, and has a preferably plural layered construction, the layered construction comprising at least one, in particular sheetlike (i.e. flat-shaped), supporting layer having two opposite sides and an adsorbing layer associated to the supporting layer and based on a material capable of adsorbing chemical poisons, wherein the surface of at least one of the two sides of the supporting layer is modified by plasma treatment. This is because Applicant has found that, surprisingly, the properties, in particular the protective or adsorptive performance, of adsorptive filtering materials can be decisively influenced and improved when the supporting layer, which is customarily present in adsorptive filtering materials of this kind, is modified at its surfaces by means of plasma treatment. Plasma treatment provides a way of specifically adjusting the surface properties, such as surface constitution (for example roughness) and surface reactivities (for example hydrophilicity or hydrophobicity on the one hand or oleophilicity or oleophobicity on the other). The fundamental idea of the present invention is thus to endow adsorptive filtering materials having a preferably plural layered construction with an enhanced protective function against chemical poisons, in particular chemical warfare agents and chemical noxiants, by the surface properties of the supporting materials, or supporting layers, customarily present in adsorptive filtering materials of this kind being modified by plasma treatment and thereby being appropriately adapted or optimized to the particular application requirements. Further advantages, properties, aspects and features of the present invention will be apparent from the following description of preferred operative examples and as depicted in the drawings. BRIEF SUMMARY An adsorptive filtering material for providing protection against chemical poisons, in particular chemical warfare agents and chemical noxiants, according to one embodiment of the present invention, preferably includes a plural layered construction, comprising at least one supporting layer having two opposite sides and an adsorbing layer associated to the supporting layer and based on a material capable of adsorbing chemical poisons, wherein the surface of at least one of the two sides of the supporting layer is modified by plasma treatment. One object of the present invention is to provide an improved adsorption filter material. Related objects and advantages of the present invention will be apparent from the following description. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1A shows a schematic section through the layered construction of an adsorptive filtering material according to a preferred operative example of the present invention where the adsorbing layer is formed by discrete fragments of adsorbent. FIG. 1B is a schematic section through the layered construction of an adsorptive filtering material according to a further preferred operative example of the present invention as per an alternative embodiment where the adsorbing layer is configured as a continuous layer of an activated carbon fiber sheetlike fabric. FIG. 2 shows a schematic section through the layered construction of an absorptive filtering material according to another preferred operative example of the invention as per a further embodiment. DETAILED DESCRIPTION For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. FIGS. 1A and 1B each show a schematic section through the layered construction 2 of a present invention adsorptive filtering material 1 . The present invention's adsorptive filtering material 1 , which is equipped with a protective function against chemical poisons, in particular chemical warfare agents and chemical noxiants, preferably comprises a plural layered construction 2 comprising at least one, in particular sheetlike, supporting layer 3 having two opposite sides 3 ′, 3 ″ and also an adsorbing layer 4 associated to the supporting layer 3 and based on a material capable of adsorbing chemical poisons. The surface of at least one of the two sides 3 ′, 3 ″ of the supporting layer 3 is modified by plasma treatment; the surface properties of the supporting layer or material 3 are thereby specifically modifiable or adjustable. As is evident from FIGS. 1A and 1B , the present invention's adsorptive filtering material 1 may further comprise at least one further, in particular sheetlike, supporting layer 5 having two opposite sides 5 ′, 5 ″. In general, the second supporting layer 5 is disposed on that side of adsorbing layer 4 which is opposite the first supporting layer 3 . The surface of at least one of the two sides 5 ′, 5 ″ of the second supporting layer 5 may similarly be modified by plasma treatment. As used herein, the term “plasma treatment” comprises every conventional method for plasma-treating supporting layers or supporting materials, in particular textile supporting layers or supporting materials, which is suitable in the realm of the present invention. Plasma is often referred to as the fourth state of matter. When a solid material is supplied with energy, it may become a liquid and, if still further energy is supplied in that state, the liquid can become a gas. When, finally, yet additional energy of the right kind is introduced, the gas can dissociate and turn into a plasma. Plasmas exist in a multiplicity of phenomena. Plasmas of very high energy and temperature are not employable in industry, in particular not for the treatment of surfaces of supporting layers. The plasma treatment contemplated by the present invention therefore utilizes in particular low pressure or vacuum processes, so that the temperature of the plasma is only minimally above the ambient temperature (so-called low temperature or cold gas plasma). This is accomplished in particular by employing a suitable energy variety and selection of a suitable gas atmosphere, and this is within the realm of the expertise of any person skilled in the art. Without wishing to be bound by a specific theory, it is believed that a plasma treatment is accompanied by various mutually competing molecular processes or reactions capable of modifying the surface or surfaces of the supporting layer or material 3 and/or of the supporting layer or material 5 , namely first by ablation (=removal of surface material by vaporization, occasionally also referred to by the synonyms of etching or plasma etching), secondly by crosslinking (=chemical bonding together of two or more polymeric chains) and thirdly by activation (=replacement of atoms in the surface by chemical groups from the plasma). These three aforementioned reactions are influenced and controlled by the gas chemistry and the operating variables (pressure, temperature, energy input, treatment time, etc.) in any one plasma-treating system. The plasma which is preferably used according to the present invention is a low temperature plasma, in particular a cold gas plasma, in particular with temperatures below 60° C., preferably below 50° C., in order that the surface to be modified is not damaged or destroyed. To achieve such low temperatures, it is customary to operate at reduced pressure or in vacuo, in particular at pressures from 0.0001 to 100 Torr and preferably from 0.001 to 10 Torr. Useful plasma-forming gases include inorganic and/or organic gases or gas mixtures, for example based on nitrogen oxides, carbon oxides, noble gases, nitrogen, oxygen, ozone and/or chlorous gases. This will be known per se to one skilled in the art. To plasma-treat the surface or surfaces to be modified, the surface or surfaces are exposed to the plasma for a sufficient period to obtain the desired surficial properties. This may be done for example by introducing the supporting layer or layers 3 and/or 5 into an appropriate plasma vacuum chamber and then allowing the plasma to act for a sufficient period on the corresponding surface or surfaces to be modified. By selecting suitable operating parameters (pressure, temperature, energy input, treatment time, selection of gases, etc.), which will be familiar per se to one skilled in the art, the surface can then be modified in the desired manner. To generate the plasma, the plasma-forming gases are generally exposed to a high frequency energy (for example in the range from 40 kHz to 3 GHz) to dissociate the plasma-forming gases into a plasma which subsequently acts on the surface to be modified. The pressure conditions, treatment time, temperature, gas selection and energy frequencies are all interrelated variables which one skilled in the art is able on the basis of his or her expertise as a person skilled in the art to specifically adjust or select with regard to the modification to be carried out. In general, the plasma treatment is carried out directly at the surface or surfaces 3 ′, 3 ″, 5 ′, 5 ″ of the supporting layers 3 and 5 respectively. But it is similarly possible for the plasma treatment to be carried out only indirectly at the surface or surfaces 3 ′, 3 ″, 5 ′, 5 ″ of the supporting layers 3 and 5 respectively by initially applying a polymeric or polymerizable film to the surface or surfaces to be treated and then crosslinking or curing the polymeric or polymerizable film by plasma treatment; polymeric or polymerizable films useful for the present invention include for example films of silicones, in particular silicone oils, or organopolysiloxanes. The plasma treatment makes it possible to specifically adjust the surface properties of the supporting layers 3 and 5 , for example the surface constitution (for example roughness) or surface reactivities. For example, by increasing the roughness it is possible to specifically increase the bonding power of adhesives to secure the adsorbing layer 4 to the supporting layer 3 or 5 . By increasing or reducing surface reactivity, it is possible for example to specifically achieve hydrophilic/hydrophobic or oleophilic/oleophobic properties for the surfaces, for example in order to obtain repellency with regard to chemical poisons, for example organic chemicals, or better or worse water-wettability. For example, an increased surficial reactivity can be experimentally characterized in terms of water wettability, i.e., the ability of a liquid, in particular water, to spread out over and penetrate into a surface. Water wettability can be measured in terms of the contact angle between the liquid, in particular water, and the surface by using reference liquids having known properties; the relationship between contact angle and surface energy/surface reactivity is direct, i.e., the contact angle decreases with the surface energy/reactivity. When the present invention's adsorptive filtering material 1 is used for example in NBC protective materials, for example in NBC protective suits, the plasma treatment can be used to modify the surface reactivity of the surface of at least one of the two sides 3 ′, 3 ″ of the supporting layer 3 on the one hand and of the surface of at least one of the two sides 5 ′, 5 ″ of the supporting layer 5 on the other to have contrary properties. The plasma treatment is used to enhance the surface reactivity of the surface of at least one of the two sides 3 ′, 3 ″ of the supporting layer 3 and reduce the surface reactivity of the surface of at least one of the two sides 5 ′, 5 ″ of the supporting layer 5 , or vice versa. For example, the plasma treatment can be used to make the surfaces of the supporting layers 3 and 5 hydrophilic or hydrophobic or else oleophilic or oleophobic. Similarly, the plasma-treated surfaces of the supporting layer 3 or 5 can be made acidic or alkaline. When the present invention's adsorptive filtering material 1 is used for example in NBC protective materials, in particular NBC protective suits, that side 3 ′ of supporting layer 3 which, in the use state of the adsorptive filtering material 1 , faces outward can be made oleophobic in order that organic chemicals may be rejected, whereas the surface of at least one of the two sides 5 ′, 5 ″ of supporting layer 5 , which faces the body side in the use state, can be made hydrophilic in order that perspiration may be better taken up and be more efficiently transported away from the body in the outward direction. The supporting layers 3 and 5 may be preferably air-pervious textile materials. Examples thereof are textile sheetlike structures of any kind, examples being wovens, formed-loop knits, drawn-loop knits, nonwoven scrims, textile composites, batts and nonwovens. The supporting layers 3 and 5 consist in general of preferably air-pervious textile materials which comprise or consist of polymeric/synthetic, preferably thermoplastic, fibers. This is necessary in order that the surfaces may be directly modified by plasma treatment. Examples of polymeric/synthetic textile fibers are polyacrylic (PAN), polyamides (PA), such as nylon 6 and nylon 66, polyesters (PES), polyolefins, in particular polyethylene (PE) and polypropylene (PP), polyvinyl alcohol (PVA1), polyvinyl chloride (CLF), polyvinylidene chloride (CLF), acetate (CA), triacetate (CTA), aramid (AR), elastane (EL), elastodiene (ED), fluoro (PTFE), rubber (LA), carbon (CF), viscose (CV) and also mixtures of the aforementioned fiber varieties. The parenthetical abbreviations are codes defined in German standard specification DIN 60001-4: 1991-08. The supporting layers 3 and 5 may consist of the aforementioned synthetic/polymeric fibrous materials or comprise these in a certain proportion (as for example in the case of blend materials composed of natural and synthetic/polymeric textile fibers). In the case of textile materials composed of purely natural textile fibers, plasma modification is made possible by prior application of a polymeric or polymerizable film, as described above. In a particularly preferred embodiment of the present invention's adsorptive filtering material 1 , at least one of the two supporting layers 3 , 5 is a PA-PES textile sheetlike structure, in particular a PA-PES batt, or is a sheetlike structure including PES fibers and is in particular a PES-cellulose textile sheetlike structure. In a preferred embodiment, the supporting layer 3 or 5 , which in the use state of the adsorptive filtering material 1 faces a noxiant source, is preferably made oleophobic on its side 3 ′ or 5 ′ facing the noxiant source, by plasma treatment, in order that droplets of organic chemical substances may be more efficiently repelled, and the supporting layer 5 or 3 , which in the use state of the adsorptive filtering material 1 faces away from a noxiant source, is preferably made hydrophilic on its side 5 ′ or 3 ′ facing away from the noxiant source, by plasma treatment, in order that moisture (for example perspiration) may be more efficiently transported away. Plasma treatment thus makes it possible to specifically modify/change the surface properties of the supporting layers 3 , 5 . Thus, the surfaces may as described in detail above be rendered for example hydrophilic or hydrophobic, oleophilic or oleophobic, acidic or alkaline, rough or smooth, etc. It is possible in particular for the two sides of the textile composite of the present invention's adsorptive filtering material 1 to be subjected to different plasma treatments and different surficial properties to be achieved on both sides. For instance, one side can be rendered hydrophilic and the other hydrophobic. The adsorbing layer 4 is generally configured as a separate layer. It is possible nonetheless to integrate the adsorbing layer 4 in the supporting layer 3 and/or 5 , so that the adsorbing layer 4 is part of the supporting layer 3 and/or 5 (as for example in the case of a PU foam laden with activated carbon). In general, however, a separate adsorbing layer 4 is preferable. As described above, the adsorbing layer 4 comprises a material capable of adsorbing chemical poisons, in particular chemical warfare agents and/or chemical noxiants. It is in particular an adsorptive filtering material based on activated carbon. Nonetheless, other adsorptive materials can be utilized, examples being molecular sieves, ion exchangers, zeolites, silica gels, etc. But activated carbon is particularly preferred for the purposes of the present invention. The adsorbing layer 4 may be secured to the supporting layer 3 and/or 5 , in particular durably secured (for example by adhering, stapling, sewing, welding or the like), more preferably by adhering (for example with a thermoplastic adhesive, for example an, in particular, moisture-crosslinking polyurethane reactive adhesive), in which case the adhesive has advantageously been applied merely discontinuously and preferably dotwise to the supporting layer 3 and/or 5 . As FIG. 1A shows, the adsorbing layer 4 in one embodiment may be discontinuous. In this case, the adsorbing layer 4 will comprise discrete adsorptive fragments capable of adsorbing chemical poisons and based on activated carbon in particular, preferably in the form of activated carbon particles and/or activated carbon fibers. Advantageously, the adsorbing layer 4 preferably comprises the discrete particles of activated carbon preferably in granule form (“granulocarbon”) or in spherical form (“spherulocarbon”), the average diameter of the activated carbon particles being less than 1.0 mm, in particular less than 0.5 mm, preferably less than 0.4 mm, but at least 0.1 mm. The activated carbon particles can be present in an amount of 5 to 500 g/m 2 , in particular 10 to 400 g/m 2 , preferably 20 to 300 g/m 2 , more preferably 25 to 250 g/m 2 . Advantageously, the internal surface areas (BET) of the activated carbon particles are at least 800 m 2 /g, in particular at least 900 m 2 /g, preferably at least 1,000 m 2 /g and are preferably in the range from 800 to 1,500 m 2 /g. To obtain a particularly good compressive strength, it is of advantage when the activated carbon particles have a burst pressure per individual activated carbon particle, in particular activated carbon granule or spherule, of at least 5 newton, in particular at least 10 newton, and the burst pressure can be up to 20 newton or more. In an alternative embodiment, depicted in FIG. 1B , the adsorbing layer 4 may also comprise activated carbon fibers, in particular in the form of an activated carbon sheetlike structure. Suitable activated carbon sheetlike structures have a basis weight of 20 to 200 g/m 2 , in particular 30 to 150 g/m 2 and preferably 50 to 120 g/m 2 . The activated carbon sheetlike structure can be in particular a woven, loop-formingly knit, nonwoven-scrim or composited activated carbon fabric, in particular on the basis of carbonized and activated cellulose and/or on the basis of a carbonized and activated acrylonitrile. To increase the adsorptive efficiency and performance, the adsorbent of the adsorbing layer 4 , in particular the activated carbon particles and/or the activated carbon fibers, may additionally be impregnated with at least one catalyst. Catalysts useful in this invention include for example enzymes and/or metal ions, preferably ions of copper, of silver, of cadmium, of platinum, of palladium, of zinc and/or of mercury. The amount of catalyst can vary within wide limits; it is generally in the range from 0.05% to 12% by weight, preferably in the range from 1% to 10% by weight and more preferably in the range from 2% to 8% by weight, based on the weight of the adsorbing layer 4 . It is further possible for the adsorptive filtering material 1 according to the present invention also to be equipped with at least one membrane 6 which retards the passage of chemical poisons or is at least essentially impervious to chemical poisons. Advantageously, this membrane 6 can be at least essentially water and air impervious, but water vapor pervious. The membrane 6 can be disposed between the first supporting layer 3 and the adsorbing layer 4 or else between the second supporting layer 5 and the adsorbing layer 4 . Advantageously, the membrane 6 is disposed such that, in the use state of the present invention's adsorptive filtering material 1 , it is disposed upstream of the adsorbing layer 4 , so that the chemical poisons initially encounter the membrane 6 . The membrane 6 may in general be a continuous, in particular uninterrupted or at most microporous membrane. The membrane 6 can be for example a membrane which is 1 to 500 μm thick, in particular 1 to 250 μm thick, preferably 1 to 100 μm and more preferably 1 to 50 μm thick, even more preferably 2.5 to 30 μm thick and most preferably 5 to 25 μm thick and comprises or consists of a plastic or a polymer. The plastic or polymer can be selected from the group of polyurethanes, polyetheramides, polyesteramides, polytetrafluoroethylenes and cellulose-based polymers and also derivatives of the aforementioned compounds. More preferably, the membrane 6 is a polyurethane-based membrane or an expanded, perhaps microporous membrane based on polytetrafluoroethylene. In a particular embodiment, the membrane 6 is a multilayered membrane laminate or a multilayered membrane composite, and the membrane laminate or composite may consist of at least two and preferably at least three mutually interbonded layers or plies. For example, the membrane laminate or composite may comprise a core layer based on a cellulose-based polymer and two outer layers bonded to the core layer in particular on the basis of a polyurethane, of a polyetheramide and/or of a polyesteramide, in which case the core layer based on a cellulose-based polymer can be constructed as a membrane from 1 to 100 μm, in particular from 5 to 50 μm and preferably from 10 to 20 μm in thickness and the two outer layers bonded to the core layer may each be constructed as a membrane from 1 to 100 μm, in particular from 5 to 50 μm and preferably from 5 to 10 μm in thickness. The particular configuration of the membrane 6 as a membrane laminate or composite makes it possible to combine various membrane materials each having different properties, in particular different water vapor transmission rates and/or permeation resistances to chemical poisons, with one another and thus achieve an optimization of the properties of the membrane 6 . For example, cellulose and cellulose derivatives are excellent barrier layer materials, in particular against chemical noxious or poisonous agents, examples being warfare agents (Hd etc.), and are not attacked or dissolved by these poisons; on the other hand, polyurethane-based materials inhibit any migration or diffusion of any plasticizers present in the cellulose layer and also muffle the rustling (due to the cellulose) which occurs in the course of use or wear. This is why it is preferable in this particular embodiment that in the case of a membrane laminate or composite where the core layer is formed on the basis of a cellulose-based polymer the two outer layers of the membrane 6 are formed by polyurethane layers. The presence of the membrane 6 , which in the use state of the present invention's adsorptive filtering material 1 is advantageously disposed upstream of the adsorbing layer 4 , has the effect that any chemical poisons, such as for example chemical warfare agents or chemical noxiants, which have succeeded in penetrating through the supporting layer 3 or 5 are unable to penetrate further into the material, in particular are unable to reach the adsorbing layer 4 at all or at least overwhelmingly so, so that the adsorptive capacity of the adsorbing layer 4 remains quasi inexhaustible. On the other hand, when the adsorptive filtering material 1 is used as an NBC protective suit, the presence of the membrane 6 provides an additional protection for the wearer of the adsorptive filtering material 1 or of the NBC protective suit, so that the result is an adsorptive filtering material 1 having so to speak twice the protective function against chemical poisons (namely on the one hand due to the blocking effect of the membrane 6 and on the other due to the adsorptive effect of the adsorbing layer 4 ). By equipping the present invention's filtering material with a specific membrane 6 which retards the passage of chemical poisons or is at least essentially impervious to chemical poisons, good decontaminability and regenerability is achieved for the present invention's adsorptive filtering material 1 at the same time. This is because any poisons which have succeeded in penetrating the supporting layers 3 and 5 and are present on the membrane 6 are readily removable off the membrane 6 through appropriate treatment processes, for example by rinsing down, for example with suitable decontaminating solutions which will be very well known for these purposes to one skilled in the art. Advantageously, the membrane 6 and thus the adsorptive filtering material 1 is constructed such that the membrane 6 /the absorptive filtering material 1 has a barrier effect with regard to chemical warfare agents, in particular bis[2-chloroethyl]sulfide (mustard gas, Hd, yellow cross), measured according to CRDEC-SP-84010, method 2.2, permitting permeation of at most 4 μg/cm 2 per 24 h, in particular at most 3.5 μg/cm 2 per 24 h, preferably at most 3.0 μg/cm 2 per 24 h and more preferably at most 2.5 μg/cm 2 per 24 h when membrane 6 is 50 μm thick. To increase the wear comfort, in particular the breathability, the membrane 6 , when measured at 25° C. and at a thickness of 50 μm, has a high water vapor transmission rate of at least 12.5 l/m 2 per 24 h, in particular at least 17.5 l/m 2 per 24 h, preferably at least 20 l/m 2 per 24 h or more (measured by the inverted cup method of ASTM E 96 and at 25° C.). For further details concerning the measurement of the water vapor transmission rate [WVTR] cf. also McCullough et al. “A comparison of standard methods for measuring water vapour permeability of fabrics” in Meas. Sci. Technology [Measurements Science and Technology] 14, 1402-1408, August 2003. This ensures a particularly high wear comfort. Owing to the multiplicity of layers 3 , 4 , 5 and 6 of the layered construction 2 , the water vapor transmission rate of the adsorptive filtering material 1 is as a whole—compared with membrane 6 alone—slightly lower; the water vapor transmission rate of the adsorptive filtering material 1 as a whole is nonetheless very high, amounting to at least 10 l/m 2 per 24 h, in particular at least 15 l/m 2 per 24 h and preferably at least 17.5 l/m 2 per 24 h when membrane 6 is 50 μm thick (at 25° C.). For reasons of breathability, the membrane 6 should have a low water vapor transmission resistance R et under steady state conditions—measured according to DIN EN 31 092: 1993 of February 1994 (“Textiles—Physiological Effects, Measurement of Heat and Water Vapor Transmission Resistance under steady state Conditions [sweating guarded-hotplate test]” or according to the equivalent international standard ISO 11 092)—at 35° C. of at most 25 (m 2 ·pascal)/watt, in particular at most 20 (m 2 ·pascal)/watt, preferably at most 13 (m 2 ·pascal)/watt, when membrane 6 is 50 μm thick. Owing to the multiplicity of layers 3 , 4 , 5 and 6 of the layered construction 2 , the water vapor transmission resistance R et of the adsorptive filtering material 1 as a whole—compared with membrane 6 alone—is slightly higher; in general, the water vapor transmission resistance R et of the adsorptive filtering material 1 as a whole is at most 30 (m 2 ·pascal)/watt, in particular at most 25 (m 2 ·pascal)/watt and preferably at most 20 (m 2 ·pascal)/watt when membrane 6 is 50 μm thick. The membrane 6 should in addition be at most only minimally water absorptive/swellable; a minimal water absorptivity/swellability enhances the wear comfort. More particularly, the swellability/water absorbency of membrane 6 should be at most 35%, in particular at most 25% and preferably at most 20%, based on membrane 6 's own weight. In addition, the membrane 6 should be at least essentially impervious to liquids, in particular water, and/or to aerosols, or at least retard their transmission. To achieve an at most minimal swellability, the membrane 6 should have no or essentially no strongly hydrophilic groups. For the purposes of minimal swelling, however, the membrane 6 may comprise weakly hydrophilic groups (for example polyether groups) or a but small number of more strongly hydrophilic groups. The use of so-called breathable membranes 6 , i.e., of, in particular, water-vapor-pervious but liquid-impervious membranes 6 , in particular in the form of thin films/foils makes it possible to achieve surprising improvements for NBC protective clothing, in particular when the adsorbing layer 4 is disposed so to speak behind the membrane 6 , i.e., downstream of membrane 6 in the use or worn state. In a very particular embodiment of the present invention, the membrane 6 can be self-adhesive, in particular heat-tacky, so that the membrane 6 can also serve as adhesive layer to secure the adsorbing layer 4 . FIG. 2 shows a present invention adsorptive filtering material 1 according to a particular refinement of the present invention. The adsorptive filtering material 1 of FIG. 2 comprises two supporting materials/layers 3 and 5 between which is disposed a sheetlike (i.e. flat-shaped) adsorbing layer based on an activated carbon fiber sheetlike (i.e. flat-shaped) structure 4 which a dotwise applied/printed adhesive 7 fixes to the supporting layers 3 and 5 . One of the two supporting layers 3 , 5 can be a PA-PES batt, while the other supporting layer of the pair can be a PES-cellulose textile sheetlike (i.e. flat-shaped) structure. One or more of the surfaces 3 ′, 3 ″, 5 ′ and/or 5 ″ of the supporting layers 3 and 5 respectively have been modified (for example hydrophobicized or hydrophilicized, oleophobicized or oleophilicized, roughened, made acidic or alkaline, etc.) by plasma treatment in accordance with the particular intended application. Such a material can be used for example in the production of NBC protective clothing. The individual layers 3 , 4 , 5 and 6 of the layered construction 2 may each be interbonded. The layered construction 2 then forms a composite/laminate. Alternatively, however, the individual layers 3 , 4 , 5 and 6 of the layered construction 2 may also be, at least some of them, placed on top of each other without bonding in between. This depends in each case on the intended application for the present invention's adsorptive filtering material 1 . The production of the present invention's absorptive filtering material 1 as a whole can be effected in a conventional manner. This will be known to those skilled in the arts of producing adsorptive filtering materials, so that no further details concerning this matter need to be discussed in this context. Altogether, the plasma modification of at least one of the surfaces 3 ′, 3 ″, 5 ′, 5 ″ of at least one of the supporting layers 3 and/or 5 results in a high-performance adsorptive filtering material 1 whose surface properties can be specifically adjusted by the plasma treatment. A hydrophilic modification, for example, provides improved water absorptivity, whereas an oleophobicization ensures improved repellency with regard to organic chemical poisons, in particular warfare agents or noxiants (for example when thickened drops of chemical poisons impinge on the supporting layers 3 and 5 ). An acidic or alkaline surficial modification, for example, is also a specific way of achieving a neutralization of certain poisons. Modifying the surfaces of the supporting layers 3 and 5 by plasma treatment thus offers a comprehensive way of specifically adjusting the surface properties of the supporting layers 3 and 5 of the present invention's adsorptive filtering material 1 over a wide range. For example, surface reactivities (for example hydrophilicity or hydrophobicity, oleophobicity or oleophilicity, etc.), surface roughnesses, acidic or alkaline properties and so on can be specifically adjusted/adapted to the particular application requirements. This decisively improves the protective efficiency of the present invention's adsorptive filtering material 1 . In particular, the two sides of the textile composite, i.e., of the adsorptive filtering material according to the present invention, may be subjected to different plasma treatments to achieve different surficial properties on the two sides. For example, one side may be made hydrophilic and the other hydrophobic. The supporting material's textile face, which is to be provided with adhesive or other coatings for example, is hydrophobicized for example. The material can then be used for extensive coatings or dotwise coatings. This ensures that coatings/dots of adhesive will optimally wet the textile face, so that good bonding is achieved coupled with minimal strikethrough of adhesive and dots of coating which remain firmly in place on the material. In this way, the necessary amounts for coatings and adhesive add-on can be economically optimized. Products are textile coatings by means of polyurethanes (so-called direct coatings), the lamination with films and breathable membranes, and also adsorptive filters with activated carbon, where in each case the side to be coated has been modified using plasma treatment. In principle, plasma treatment is advantageous in the production of all kinds of textile composites. Examples of adhesives used are moisture-crosslinking polyurethane reactive adhesives, High Solids® and polyurethane coatings. When the textile substrate to be coated is also worn in textiles as a liner side facing the body, it is sensible from the viewpoint of clothing comfort to make the inside surface hydrophilic in order that good removal of perspiration from the skin may be achieved. It is preferable in this context to use textile substrates composed of polyamide or polyester. Useful plasma-treating methods for the present invention include for example treatments by means of atmospheric plasma or high-vacuum plasma to mention but a few by way of example. As described above, the adsorptive filtering material of the present invention is useful for producing protective materials of any kind, in particular protective suits, protective gloves, protective shoes and protective covers. The present invention thus also provides for the use of the adsorptive filtering material of the present invention for the aforementioned protective materials and also the protective materials themselves which are produced using the adsorptive filtering material of the present invention, in particular protective suits, protective gloves, protective shoes and protective covers, preferably for NBC deployment. Further refinements, modifications and variations of the present invention will become apparent to and realizable by the ordinarily skilled after reading the description without their having to depart from the realm of the present invention. While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.
The invention relates to an adsorption filter material ( 1 ) that provides protection against chemical toxins, chemical weapons and pollutants, with a preferably multi-layer composite construction ( 2 ). The layer construction ( 2 ) includes at least one planar support layer ( 3 ) with two opposing sides ( 3′, 3″ ) and an adsorption layer ( 4 ), provided on the support layer ( 3 ) made from a material which adsorbs chemical toxins, the surface of at least one of the both sides ( 3′ and/or 3″ ) of the support layer ( 3 ) being modified by plasma treatment. The surface properties, in particular the surface finish and the surface reactivity can be adjusted and optimised to match the application by means of the plasma treatment.
Identify and summarize the most critical technical features from the given patent document.
[ "CROSS-REFERENCES TO RELATED APPLICATIONS This application is a continuation of U.S. application Ser.", "No. 10/581,329, filed Aug. 30, 2006, now U.S. Pat. No. 7,572,322, which is hereby incorporated by reference in its entirety, and which is a National Stage filing of International Application PCT/EP2004/010036, filed Sep. 9, 2004, claiming priority to German Application No. DE 103 56 776.3, filed Dec. 2, 2003, entitled “PLASMA-TREATED SURFACES FOR ADSORPTION FILTER MATERIALS.”", "The application claims priority to PCT/EP2004/010036 and to German Application No DE 103 56 776.3 and both references are expressly incorporated by reference herein, in their entirety.", "BACKGROUND OF THE INVENTION The present invention relates to plasma-treated textile surfaces for use in adsorptive filtering materials.", "More particularly, the present invention relates to an adsorptive filtering material having protective function against chemical poisons, in particular chemical warfare agents and chemical noxiants, as classified and disclosed herein, in particular for the production of protective materials, such as protective suits, protective gloves, protective shoes, protective covers (for example to transport casualties) and the like, in particular for NBC deployment, and also to the aforementioned protective materials produced using this adsorptive filtering material.", "There are a whole series of entities which are absorbed by the skin and lead to serious physical harm.", "Examples include the blister agent Hd (yellow cross) and the nerve gas sarin.", "People liable to come into contact with such poisons have to wear a suitable protective suit or be protected against these poisons by suitable protective materials.", "There are in principle three types of protective suits: the air- and water-vapor-impervious protective suits which are equipped with a layer of rubber impervious to chemical poisons and which very rapidly lead to a build-up of heat;", "the air- and water-vapor-pervious protective suits which offer the highest wear comfort;", "and finally protective suits which are equipped with a membrane which allows water vapor but not the aforementioned poisons through.", "NBC protective clothing is thus traditionally produced either from completely impermeable systems (for example suits composed of butyl rubber) or permeable, adsorptive filtering systems based on activated carbon (in pulverulent, fibrous or spherulous form).", "Protective suits against chemical warfare agents that are intended for prolonged use under a wide variety of conditions must not lead to a build-up of heat for the wearer.", "Air-pervious materials are therefore used in the main.", "The air-pervious, permeable protective suits generally possess an adsorbing layer comprising activated carbon which binds the chemical poisons very durably, so that even badly contaminated suits do not pose any danger to the wearer.", "The great advantage of this system is that the activated carbon is accessible on the inside as well as the outside, so that poisons which have succeeded in penetrating at damaged or otherwise unproof locations are very rapidly adsorbed.", "However, under extreme conditions, for example when a drop of a thickened poison impinges from a considerable height onto a somewhat open location on the outer material and is able to strike through to the activated carbon, the carbon layer may locally not be up to its task for a brief period.", "The present invention therefore has for its object to provide an adsorptive filtering or protective material which at least substantially avoids the prior art disadvantages described above and which is especially useful for the production of NBC protective materials, such as protective suits, protective gloves, protective shoes, protective covers and the like.", "This object is achieved in the realm of the present invention by an adsorptive filtering material as disclosed and claimed herein.", "Further, advantageous refinements of the adsorptive filtering material according to the preferred embodiment of the present invention are disclosed and claimed herein.", "The present invention further provides for the use of the present invention's adsorptive filtering material for producing protective materials of any kind, in particular for producing protective suits, protective gloves, protective shoes and protective covers, preferably for NBC deployment, and also the thus produced protective materials of the aforementioned kind themselves.", "According to a first aspect of the present invention there is accordingly provided an adsorptive filtering material which provides protection against chemical poisons, in particular chemical warfare agents and chemical noxiants, and has a preferably plural layered construction, the layered construction comprising at least one, in particular sheetlike (i.e. flat-shaped), supporting layer having two opposite sides and an adsorbing layer associated to the supporting layer and based on a material capable of adsorbing chemical poisons, wherein the surface of at least one of the two sides of the supporting layer is modified by plasma treatment.", "This is because Applicant has found that, surprisingly, the properties, in particular the protective or adsorptive performance, of adsorptive filtering materials can be decisively influenced and improved when the supporting layer, which is customarily present in adsorptive filtering materials of this kind, is modified at its surfaces by means of plasma treatment.", "Plasma treatment provides a way of specifically adjusting the surface properties, such as surface constitution (for example roughness) and surface reactivities (for example hydrophilicity or hydrophobicity on the one hand or oleophilicity or oleophobicity on the other).", "The fundamental idea of the present invention is thus to endow adsorptive filtering materials having a preferably plural layered construction with an enhanced protective function against chemical poisons, in particular chemical warfare agents and chemical noxiants, by the surface properties of the supporting materials, or supporting layers, customarily present in adsorptive filtering materials of this kind being modified by plasma treatment and thereby being appropriately adapted or optimized to the particular application requirements.", "Further advantages, properties, aspects and features of the present invention will be apparent from the following description of preferred operative examples and as depicted in the drawings.", "BRIEF SUMMARY An adsorptive filtering material for providing protection against chemical poisons, in particular chemical warfare agents and chemical noxiants, according to one embodiment of the present invention, preferably includes a plural layered construction, comprising at least one supporting layer having two opposite sides and an adsorbing layer associated to the supporting layer and based on a material capable of adsorbing chemical poisons, wherein the surface of at least one of the two sides of the supporting layer is modified by plasma treatment.", "One object of the present invention is to provide an improved adsorption filter material.", "Related objects and advantages of the present invention will be apparent from the following description.", "BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1A shows a schematic section through the layered construction of an adsorptive filtering material according to a preferred operative example of the present invention where the adsorbing layer is formed by discrete fragments of adsorbent.", "FIG. 1B is a schematic section through the layered construction of an adsorptive filtering material according to a further preferred operative example of the present invention as per an alternative embodiment where the adsorbing layer is configured as a continuous layer of an activated carbon fiber sheetlike fabric.", "FIG. 2 shows a schematic section through the layered construction of an absorptive filtering material according to another preferred operative example of the invention as per a further embodiment.", "DETAILED DESCRIPTION For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same.", "It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.", "FIGS. 1A and 1B each show a schematic section through the layered construction 2 of a present invention adsorptive filtering material 1 .", "The present invention's adsorptive filtering material 1 , which is equipped with a protective function against chemical poisons, in particular chemical warfare agents and chemical noxiants, preferably comprises a plural layered construction 2 comprising at least one, in particular sheetlike, supporting layer 3 having two opposite sides 3 ′, 3 ″ and also an adsorbing layer 4 associated to the supporting layer 3 and based on a material capable of adsorbing chemical poisons.", "The surface of at least one of the two sides 3 ′, 3 ″ of the supporting layer 3 is modified by plasma treatment;", "the surface properties of the supporting layer or material 3 are thereby specifically modifiable or adjustable.", "As is evident from FIGS. 1A and 1B , the present invention's adsorptive filtering material 1 may further comprise at least one further, in particular sheetlike, supporting layer 5 having two opposite sides 5 ′, 5 ″.", "In general, the second supporting layer 5 is disposed on that side of adsorbing layer 4 which is opposite the first supporting layer 3 .", "The surface of at least one of the two sides 5 ′, 5 ″ of the second supporting layer 5 may similarly be modified by plasma treatment.", "As used herein, the term “plasma treatment”", "comprises every conventional method for plasma-treating supporting layers or supporting materials, in particular textile supporting layers or supporting materials, which is suitable in the realm of the present invention.", "Plasma is often referred to as the fourth state of matter.", "When a solid material is supplied with energy, it may become a liquid and, if still further energy is supplied in that state, the liquid can become a gas.", "When, finally, yet additional energy of the right kind is introduced, the gas can dissociate and turn into a plasma.", "Plasmas exist in a multiplicity of phenomena.", "Plasmas of very high energy and temperature are not employable in industry, in particular not for the treatment of surfaces of supporting layers.", "The plasma treatment contemplated by the present invention therefore utilizes in particular low pressure or vacuum processes, so that the temperature of the plasma is only minimally above the ambient temperature (so-called low temperature or cold gas plasma).", "This is accomplished in particular by employing a suitable energy variety and selection of a suitable gas atmosphere, and this is within the realm of the expertise of any person skilled in the art.", "Without wishing to be bound by a specific theory, it is believed that a plasma treatment is accompanied by various mutually competing molecular processes or reactions capable of modifying the surface or surfaces of the supporting layer or material 3 and/or of the supporting layer or material 5 , namely first by ablation (=removal of surface material by vaporization, occasionally also referred to by the synonyms of etching or plasma etching), secondly by crosslinking (=chemical bonding together of two or more polymeric chains) and thirdly by activation (=replacement of atoms in the surface by chemical groups from the plasma).", "These three aforementioned reactions are influenced and controlled by the gas chemistry and the operating variables (pressure, temperature, energy input, treatment time, etc.) in any one plasma-treating system.", "The plasma which is preferably used according to the present invention is a low temperature plasma, in particular a cold gas plasma, in particular with temperatures below 60° C., preferably below 50° C., in order that the surface to be modified is not damaged or destroyed.", "To achieve such low temperatures, it is customary to operate at reduced pressure or in vacuo, in particular at pressures from 0.0001 to 100 Torr and preferably from 0.001 to 10 Torr.", "Useful plasma-forming gases include inorganic and/or organic gases or gas mixtures, for example based on nitrogen oxides, carbon oxides, noble gases, nitrogen, oxygen, ozone and/or chlorous gases.", "This will be known per se to one skilled in the art.", "To plasma-treat the surface or surfaces to be modified, the surface or surfaces are exposed to the plasma for a sufficient period to obtain the desired surficial properties.", "This may be done for example by introducing the supporting layer or layers 3 and/or 5 into an appropriate plasma vacuum chamber and then allowing the plasma to act for a sufficient period on the corresponding surface or surfaces to be modified.", "By selecting suitable operating parameters (pressure, temperature, energy input, treatment time, selection of gases, etc.), which will be familiar per se to one skilled in the art, the surface can then be modified in the desired manner.", "To generate the plasma, the plasma-forming gases are generally exposed to a high frequency energy (for example in the range from 40 kHz to 3 GHz) to dissociate the plasma-forming gases into a plasma which subsequently acts on the surface to be modified.", "The pressure conditions, treatment time, temperature, gas selection and energy frequencies are all interrelated variables which one skilled in the art is able on the basis of his or her expertise as a person skilled in the art to specifically adjust or select with regard to the modification to be carried out.", "In general, the plasma treatment is carried out directly at the surface or surfaces 3 ′, 3 ″, 5 ′, 5 ″ of the supporting layers 3 and 5 respectively.", "But it is similarly possible for the plasma treatment to be carried out only indirectly at the surface or surfaces 3 ′, 3 ″, 5 ′, 5 ″ of the supporting layers 3 and 5 respectively by initially applying a polymeric or polymerizable film to the surface or surfaces to be treated and then crosslinking or curing the polymeric or polymerizable film by plasma treatment;", "polymeric or polymerizable films useful for the present invention include for example films of silicones, in particular silicone oils, or organopolysiloxanes.", "The plasma treatment makes it possible to specifically adjust the surface properties of the supporting layers 3 and 5 , for example the surface constitution (for example roughness) or surface reactivities.", "For example, by increasing the roughness it is possible to specifically increase the bonding power of adhesives to secure the adsorbing layer 4 to the supporting layer 3 or 5 .", "By increasing or reducing surface reactivity, it is possible for example to specifically achieve hydrophilic/hydrophobic or oleophilic/oleophobic properties for the surfaces, for example in order to obtain repellency with regard to chemical poisons, for example organic chemicals, or better or worse water-wettability.", "For example, an increased surficial reactivity can be experimentally characterized in terms of water wettability, i.e., the ability of a liquid, in particular water, to spread out over and penetrate into a surface.", "Water wettability can be measured in terms of the contact angle between the liquid, in particular water, and the surface by using reference liquids having known properties;", "the relationship between contact angle and surface energy/surface reactivity is direct, i.e., the contact angle decreases with the surface energy/reactivity.", "When the present invention's adsorptive filtering material 1 is used for example in NBC protective materials, for example in NBC protective suits, the plasma treatment can be used to modify the surface reactivity of the surface of at least one of the two sides 3 ′, 3 ″ of the supporting layer 3 on the one hand and of the surface of at least one of the two sides 5 ′, 5 ″ of the supporting layer 5 on the other to have contrary properties.", "The plasma treatment is used to enhance the surface reactivity of the surface of at least one of the two sides 3 ′, 3 ″ of the supporting layer 3 and reduce the surface reactivity of the surface of at least one of the two sides 5 ′, 5 ″ of the supporting layer 5 , or vice versa.", "For example, the plasma treatment can be used to make the surfaces of the supporting layers 3 and 5 hydrophilic or hydrophobic or else oleophilic or oleophobic.", "Similarly, the plasma-treated surfaces of the supporting layer 3 or 5 can be made acidic or alkaline.", "When the present invention's adsorptive filtering material 1 is used for example in NBC protective materials, in particular NBC protective suits, that side 3 ′ of supporting layer 3 which, in the use state of the adsorptive filtering material 1 , faces outward can be made oleophobic in order that organic chemicals may be rejected, whereas the surface of at least one of the two sides 5 ′, 5 ″ of supporting layer 5 , which faces the body side in the use state, can be made hydrophilic in order that perspiration may be better taken up and be more efficiently transported away from the body in the outward direction.", "The supporting layers 3 and 5 may be preferably air-pervious textile materials.", "Examples thereof are textile sheetlike structures of any kind, examples being wovens, formed-loop knits, drawn-loop knits, nonwoven scrims, textile composites, batts and nonwovens.", "The supporting layers 3 and 5 consist in general of preferably air-pervious textile materials which comprise or consist of polymeric/synthetic, preferably thermoplastic, fibers.", "This is necessary in order that the surfaces may be directly modified by plasma treatment.", "Examples of polymeric/synthetic textile fibers are polyacrylic (PAN), polyamides (PA), such as nylon 6 and nylon 66, polyesters (PES), polyolefins, in particular polyethylene (PE) and polypropylene (PP), polyvinyl alcohol (PVA1), polyvinyl chloride (CLF), polyvinylidene chloride (CLF), acetate (CA), triacetate (CTA), aramid (AR), elastane (EL), elastodiene (ED), fluoro (PTFE), rubber (LA), carbon (CF), viscose (CV) and also mixtures of the aforementioned fiber varieties.", "The parenthetical abbreviations are codes defined in German standard specification DIN 60001-4: 1991-08.", "The supporting layers 3 and 5 may consist of the aforementioned synthetic/polymeric fibrous materials or comprise these in a certain proportion (as for example in the case of blend materials composed of natural and synthetic/polymeric textile fibers).", "In the case of textile materials composed of purely natural textile fibers, plasma modification is made possible by prior application of a polymeric or polymerizable film, as described above.", "In a particularly preferred embodiment of the present invention's adsorptive filtering material 1 , at least one of the two supporting layers 3 , 5 is a PA-PES textile sheetlike structure, in particular a PA-PES batt, or is a sheetlike structure including PES fibers and is in particular a PES-cellulose textile sheetlike structure.", "In a preferred embodiment, the supporting layer 3 or 5 , which in the use state of the adsorptive filtering material 1 faces a noxiant source, is preferably made oleophobic on its side 3 ′ or 5 ′ facing the noxiant source, by plasma treatment, in order that droplets of organic chemical substances may be more efficiently repelled, and the supporting layer 5 or 3 , which in the use state of the adsorptive filtering material 1 faces away from a noxiant source, is preferably made hydrophilic on its side 5 ′ or 3 ′ facing away from the noxiant source, by plasma treatment, in order that moisture (for example perspiration) may be more efficiently transported away.", "Plasma treatment thus makes it possible to specifically modify/change the surface properties of the supporting layers 3 , 5 .", "Thus, the surfaces may as described in detail above be rendered for example hydrophilic or hydrophobic, oleophilic or oleophobic, acidic or alkaline, rough or smooth, etc.", "It is possible in particular for the two sides of the textile composite of the present invention's adsorptive filtering material 1 to be subjected to different plasma treatments and different surficial properties to be achieved on both sides.", "For instance, one side can be rendered hydrophilic and the other hydrophobic.", "The adsorbing layer 4 is generally configured as a separate layer.", "It is possible nonetheless to integrate the adsorbing layer 4 in the supporting layer 3 and/or 5 , so that the adsorbing layer 4 is part of the supporting layer 3 and/or 5 (as for example in the case of a PU foam laden with activated carbon).", "In general, however, a separate adsorbing layer 4 is preferable.", "As described above, the adsorbing layer 4 comprises a material capable of adsorbing chemical poisons, in particular chemical warfare agents and/or chemical noxiants.", "It is in particular an adsorptive filtering material based on activated carbon.", "Nonetheless, other adsorptive materials can be utilized, examples being molecular sieves, ion exchangers, zeolites, silica gels, etc.", "But activated carbon is particularly preferred for the purposes of the present invention.", "The adsorbing layer 4 may be secured to the supporting layer 3 and/or 5 , in particular durably secured (for example by adhering, stapling, sewing, welding or the like), more preferably by adhering (for example with a thermoplastic adhesive, for example an, in particular, moisture-crosslinking polyurethane reactive adhesive), in which case the adhesive has advantageously been applied merely discontinuously and preferably dotwise to the supporting layer 3 and/or 5 .", "As FIG. 1A shows, the adsorbing layer 4 in one embodiment may be discontinuous.", "In this case, the adsorbing layer 4 will comprise discrete adsorptive fragments capable of adsorbing chemical poisons and based on activated carbon in particular, preferably in the form of activated carbon particles and/or activated carbon fibers.", "Advantageously, the adsorbing layer 4 preferably comprises the discrete particles of activated carbon preferably in granule form (“granulocarbon”) or in spherical form (“spherulocarbon”), the average diameter of the activated carbon particles being less than 1.0 mm, in particular less than 0.5 mm, preferably less than 0.4 mm, but at least 0.1 mm.", "The activated carbon particles can be present in an amount of 5 to 500 g/m 2 , in particular 10 to 400 g/m 2 , preferably 20 to 300 g/m 2 , more preferably 25 to 250 g/m 2 .", "Advantageously, the internal surface areas (BET) of the activated carbon particles are at least 800 m 2 /g, in particular at least 900 m 2 /g, preferably at least 1,000 m 2 /g and are preferably in the range from 800 to 1,500 m 2 /g.", "To obtain a particularly good compressive strength, it is of advantage when the activated carbon particles have a burst pressure per individual activated carbon particle, in particular activated carbon granule or spherule, of at least 5 newton, in particular at least 10 newton, and the burst pressure can be up to 20 newton or more.", "In an alternative embodiment, depicted in FIG. 1B , the adsorbing layer 4 may also comprise activated carbon fibers, in particular in the form of an activated carbon sheetlike structure.", "Suitable activated carbon sheetlike structures have a basis weight of 20 to 200 g/m 2 , in particular 30 to 150 g/m 2 and preferably 50 to 120 g/m 2 .", "The activated carbon sheetlike structure can be in particular a woven, loop-formingly knit, nonwoven-scrim or composited activated carbon fabric, in particular on the basis of carbonized and activated cellulose and/or on the basis of a carbonized and activated acrylonitrile.", "To increase the adsorptive efficiency and performance, the adsorbent of the adsorbing layer 4 , in particular the activated carbon particles and/or the activated carbon fibers, may additionally be impregnated with at least one catalyst.", "Catalysts useful in this invention include for example enzymes and/or metal ions, preferably ions of copper, of silver, of cadmium, of platinum, of palladium, of zinc and/or of mercury.", "The amount of catalyst can vary within wide limits;", "it is generally in the range from 0.05% to 12% by weight, preferably in the range from 1% to 10% by weight and more preferably in the range from 2% to 8% by weight, based on the weight of the adsorbing layer 4 .", "It is further possible for the adsorptive filtering material 1 according to the present invention also to be equipped with at least one membrane 6 which retards the passage of chemical poisons or is at least essentially impervious to chemical poisons.", "Advantageously, this membrane 6 can be at least essentially water and air impervious, but water vapor pervious.", "The membrane 6 can be disposed between the first supporting layer 3 and the adsorbing layer 4 or else between the second supporting layer 5 and the adsorbing layer 4 .", "Advantageously, the membrane 6 is disposed such that, in the use state of the present invention's adsorptive filtering material 1 , it is disposed upstream of the adsorbing layer 4 , so that the chemical poisons initially encounter the membrane 6 .", "The membrane 6 may in general be a continuous, in particular uninterrupted or at most microporous membrane.", "The membrane 6 can be for example a membrane which is 1 to 500 μm thick, in particular 1 to 250 μm thick, preferably 1 to 100 μm and more preferably 1 to 50 μm thick, even more preferably 2.5 to 30 μm thick and most preferably 5 to 25 μm thick and comprises or consists of a plastic or a polymer.", "The plastic or polymer can be selected from the group of polyurethanes, polyetheramides, polyesteramides, polytetrafluoroethylenes and cellulose-based polymers and also derivatives of the aforementioned compounds.", "More preferably, the membrane 6 is a polyurethane-based membrane or an expanded, perhaps microporous membrane based on polytetrafluoroethylene.", "In a particular embodiment, the membrane 6 is a multilayered membrane laminate or a multilayered membrane composite, and the membrane laminate or composite may consist of at least two and preferably at least three mutually interbonded layers or plies.", "For example, the membrane laminate or composite may comprise a core layer based on a cellulose-based polymer and two outer layers bonded to the core layer in particular on the basis of a polyurethane, of a polyetheramide and/or of a polyesteramide, in which case the core layer based on a cellulose-based polymer can be constructed as a membrane from 1 to 100 μm, in particular from 5 to 50 μm and preferably from 10 to 20 μm in thickness and the two outer layers bonded to the core layer may each be constructed as a membrane from 1 to 100 μm, in particular from 5 to 50 μm and preferably from 5 to 10 μm in thickness.", "The particular configuration of the membrane 6 as a membrane laminate or composite makes it possible to combine various membrane materials each having different properties, in particular different water vapor transmission rates and/or permeation resistances to chemical poisons, with one another and thus achieve an optimization of the properties of the membrane 6 .", "For example, cellulose and cellulose derivatives are excellent barrier layer materials, in particular against chemical noxious or poisonous agents, examples being warfare agents (Hd etc.), and are not attacked or dissolved by these poisons;", "on the other hand, polyurethane-based materials inhibit any migration or diffusion of any plasticizers present in the cellulose layer and also muffle the rustling (due to the cellulose) which occurs in the course of use or wear.", "This is why it is preferable in this particular embodiment that in the case of a membrane laminate or composite where the core layer is formed on the basis of a cellulose-based polymer the two outer layers of the membrane 6 are formed by polyurethane layers.", "The presence of the membrane 6 , which in the use state of the present invention's adsorptive filtering material 1 is advantageously disposed upstream of the adsorbing layer 4 , has the effect that any chemical poisons, such as for example chemical warfare agents or chemical noxiants, which have succeeded in penetrating through the supporting layer 3 or 5 are unable to penetrate further into the material, in particular are unable to reach the adsorbing layer 4 at all or at least overwhelmingly so, so that the adsorptive capacity of the adsorbing layer 4 remains quasi inexhaustible.", "On the other hand, when the adsorptive filtering material 1 is used as an NBC protective suit, the presence of the membrane 6 provides an additional protection for the wearer of the adsorptive filtering material 1 or of the NBC protective suit, so that the result is an adsorptive filtering material 1 having so to speak twice the protective function against chemical poisons (namely on the one hand due to the blocking effect of the membrane 6 and on the other due to the adsorptive effect of the adsorbing layer 4 ).", "By equipping the present invention's filtering material with a specific membrane 6 which retards the passage of chemical poisons or is at least essentially impervious to chemical poisons, good decontaminability and regenerability is achieved for the present invention's adsorptive filtering material 1 at the same time.", "This is because any poisons which have succeeded in penetrating the supporting layers 3 and 5 and are present on the membrane 6 are readily removable off the membrane 6 through appropriate treatment processes, for example by rinsing down, for example with suitable decontaminating solutions which will be very well known for these purposes to one skilled in the art.", "Advantageously, the membrane 6 and thus the adsorptive filtering material 1 is constructed such that the membrane 6 /the absorptive filtering material 1 has a barrier effect with regard to chemical warfare agents, in particular bis[2-chloroethyl]sulfide (mustard gas, Hd, yellow cross), measured according to CRDEC-SP-84010, method 2.2, permitting permeation of at most 4 μg/cm 2 per 24 h, in particular at most 3.5 μg/cm 2 per 24 h, preferably at most 3.0 μg/cm 2 per 24 h and more preferably at most 2.5 μg/cm 2 per 24 h when membrane 6 is 50 μm thick.", "To increase the wear comfort, in particular the breathability, the membrane 6 , when measured at 25° C. and at a thickness of 50 μm, has a high water vapor transmission rate of at least 12.5 l/m 2 per 24 h, in particular at least 17.5 l/m 2 per 24 h, preferably at least 20 l/m 2 per 24 h or more (measured by the inverted cup method of ASTM E 96 and at 25° C.).", "For further details concerning the measurement of the water vapor transmission rate [WVTR] cf.", "also McCullough et al.", "“A comparison of standard methods for measuring water vapour permeability of fabrics”", "in Meas.", "Sci.", "Technology [Measurements Science and Technology] 14, 1402-1408, August 2003.", "This ensures a particularly high wear comfort.", "Owing to the multiplicity of layers 3 , 4 , 5 and 6 of the layered construction 2 , the water vapor transmission rate of the adsorptive filtering material 1 is as a whole—compared with membrane 6 alone—slightly lower;", "the water vapor transmission rate of the adsorptive filtering material 1 as a whole is nonetheless very high, amounting to at least 10 l/m 2 per 24 h, in particular at least 15 l/m 2 per 24 h and preferably at least 17.5 l/m 2 per 24 h when membrane 6 is 50 μm thick (at 25° C.).", "For reasons of breathability, the membrane 6 should have a low water vapor transmission resistance R et under steady state conditions—measured according to DIN EN 31 092: 1993 of February 1994 (“Textiles—Physiological Effects, Measurement of Heat and Water Vapor Transmission Resistance under steady state Conditions [sweating guarded-hotplate test]”", "or according to the equivalent international standard ISO 11 092)—at 35° C. of at most 25 (m 2 ·pascal)/watt, in particular at most 20 (m 2 ·pascal)/watt, preferably at most 13 (m 2 ·pascal)/watt, when membrane 6 is 50 μm thick.", "Owing to the multiplicity of layers 3 , 4 , 5 and 6 of the layered construction 2 , the water vapor transmission resistance R et of the adsorptive filtering material 1 as a whole—compared with membrane 6 alone—is slightly higher;", "in general, the water vapor transmission resistance R et of the adsorptive filtering material 1 as a whole is at most 30 (m 2 ·pascal)/watt, in particular at most 25 (m 2 ·pascal)/watt and preferably at most 20 (m 2 ·pascal)/watt when membrane 6 is 50 μm thick.", "The membrane 6 should in addition be at most only minimally water absorptive/swellable;", "a minimal water absorptivity/swellability enhances the wear comfort.", "More particularly, the swellability/water absorbency of membrane 6 should be at most 35%, in particular at most 25% and preferably at most 20%, based on membrane 6 's own weight.", "In addition, the membrane 6 should be at least essentially impervious to liquids, in particular water, and/or to aerosols, or at least retard their transmission.", "To achieve an at most minimal swellability, the membrane 6 should have no or essentially no strongly hydrophilic groups.", "For the purposes of minimal swelling, however, the membrane 6 may comprise weakly hydrophilic groups (for example polyether groups) or a but small number of more strongly hydrophilic groups.", "The use of so-called breathable membranes 6 , i.e., of, in particular, water-vapor-pervious but liquid-impervious membranes 6 , in particular in the form of thin films/foils makes it possible to achieve surprising improvements for NBC protective clothing, in particular when the adsorbing layer 4 is disposed so to speak behind the membrane 6 , i.e., downstream of membrane 6 in the use or worn state.", "In a very particular embodiment of the present invention, the membrane 6 can be self-adhesive, in particular heat-tacky, so that the membrane 6 can also serve as adhesive layer to secure the adsorbing layer 4 .", "FIG. 2 shows a present invention adsorptive filtering material 1 according to a particular refinement of the present invention.", "The adsorptive filtering material 1 of FIG. 2 comprises two supporting materials/layers 3 and 5 between which is disposed a sheetlike (i.e. flat-shaped) adsorbing layer based on an activated carbon fiber sheetlike (i.e. flat-shaped) structure 4 which a dotwise applied/printed adhesive 7 fixes to the supporting layers 3 and 5 .", "One of the two supporting layers 3 , 5 can be a PA-PES batt, while the other supporting layer of the pair can be a PES-cellulose textile sheetlike (i.e. flat-shaped) structure.", "One or more of the surfaces 3 ′, 3 ″, 5 ′ and/or 5 ″ of the supporting layers 3 and 5 respectively have been modified (for example hydrophobicized or hydrophilicized, oleophobicized or oleophilicized, roughened, made acidic or alkaline, etc.) by plasma treatment in accordance with the particular intended application.", "Such a material can be used for example in the production of NBC protective clothing.", "The individual layers 3 , 4 , 5 and 6 of the layered construction 2 may each be interbonded.", "The layered construction 2 then forms a composite/laminate.", "Alternatively, however, the individual layers 3 , 4 , 5 and 6 of the layered construction 2 may also be, at least some of them, placed on top of each other without bonding in between.", "This depends in each case on the intended application for the present invention's adsorptive filtering material 1 .", "The production of the present invention's absorptive filtering material 1 as a whole can be effected in a conventional manner.", "This will be known to those skilled in the arts of producing adsorptive filtering materials, so that no further details concerning this matter need to be discussed in this context.", "Altogether, the plasma modification of at least one of the surfaces 3 ′, 3 ″, 5 ′, 5 ″ of at least one of the supporting layers 3 and/or 5 results in a high-performance adsorptive filtering material 1 whose surface properties can be specifically adjusted by the plasma treatment.", "A hydrophilic modification, for example, provides improved water absorptivity, whereas an oleophobicization ensures improved repellency with regard to organic chemical poisons, in particular warfare agents or noxiants (for example when thickened drops of chemical poisons impinge on the supporting layers 3 and 5 ).", "An acidic or alkaline surficial modification, for example, is also a specific way of achieving a neutralization of certain poisons.", "Modifying the surfaces of the supporting layers 3 and 5 by plasma treatment thus offers a comprehensive way of specifically adjusting the surface properties of the supporting layers 3 and 5 of the present invention's adsorptive filtering material 1 over a wide range.", "For example, surface reactivities (for example hydrophilicity or hydrophobicity, oleophobicity or oleophilicity, etc.), surface roughnesses, acidic or alkaline properties and so on can be specifically adjusted/adapted to the particular application requirements.", "This decisively improves the protective efficiency of the present invention's adsorptive filtering material 1 .", "In particular, the two sides of the textile composite, i.e., of the adsorptive filtering material according to the present invention, may be subjected to different plasma treatments to achieve different surficial properties on the two sides.", "For example, one side may be made hydrophilic and the other hydrophobic.", "The supporting material's textile face, which is to be provided with adhesive or other coatings for example, is hydrophobicized for example.", "The material can then be used for extensive coatings or dotwise coatings.", "This ensures that coatings/dots of adhesive will optimally wet the textile face, so that good bonding is achieved coupled with minimal strikethrough of adhesive and dots of coating which remain firmly in place on the material.", "In this way, the necessary amounts for coatings and adhesive add-on can be economically optimized.", "Products are textile coatings by means of polyurethanes (so-called direct coatings), the lamination with films and breathable membranes, and also adsorptive filters with activated carbon, where in each case the side to be coated has been modified using plasma treatment.", "In principle, plasma treatment is advantageous in the production of all kinds of textile composites.", "Examples of adhesives used are moisture-crosslinking polyurethane reactive adhesives, High Solids® and polyurethane coatings.", "When the textile substrate to be coated is also worn in textiles as a liner side facing the body, it is sensible from the viewpoint of clothing comfort to make the inside surface hydrophilic in order that good removal of perspiration from the skin may be achieved.", "It is preferable in this context to use textile substrates composed of polyamide or polyester.", "Useful plasma-treating methods for the present invention include for example treatments by means of atmospheric plasma or high-vacuum plasma to mention but a few by way of example.", "As described above, the adsorptive filtering material of the present invention is useful for producing protective materials of any kind, in particular protective suits, protective gloves, protective shoes and protective covers.", "The present invention thus also provides for the use of the adsorptive filtering material of the present invention for the aforementioned protective materials and also the protective materials themselves which are produced using the adsorptive filtering material of the present invention, in particular protective suits, protective gloves, protective shoes and protective covers, preferably for NBC deployment.", "Further refinements, modifications and variations of the present invention will become apparent to and realizable by the ordinarily skilled after reading the description without their having to depart from the realm of the present invention.", "While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected." ]
CROSS-REFERENCE TO RELATED APPLICATIONS The present disclosure is a divisional of U.S. patent application Ser. No. 10/812,626 (now U.S. Pat. No. 8,665,486), filed on Mar. 29, 2004. The entire disclosure of the application referenced above is incorporated herein by reference. FIELD Embodiments of the present invention relate generally to image data processing, and in particular, look-up tables used in image data processing. BACKGROUND Today, an ever-increasing number of mobile devices, such as PDAs and cellular telephones, are being outfitted with digital cameras and video recorders. Such digital cameras use sensors to which capture images in a digital data format, i.e., as bits; zeros and ones. Digital data processing involves manipulating these bits to enhance the resultant image, or for other purposes, such as convenient storage. There are numerous well-known image data processing operations that can be performed on digital image data. These include companding (reducing the bit-depth of the image data), gamma correction (compensating for brightness differences), sensor correction (compensating for sensor non-linearity), and illumination correction (compensating for changed illumination environment, e.g. inside or outside) to name a few. All of the data processing operations mentioned above may be implemented using a transfer function to describe the appropriate adjustment. A transfer function is merely a function that maps input values to output values according to a formula or curve. Transfer functions can be implemented in hardware as look-up tables (LUT) to increase processing speed. However, a full LUT representing all possible outputs of a transfer function takes up a lot of memory. One way to reduce the memory required to store the LUT is to have the LUT store only sample outputs of the transfer function. However, sampling the transfer function compromises accuracy and flexibility. BRIEF DESCRIPTION OF DRAWINGS Embodiments of the present invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements and in which: FIG. 1 is a block diagram of an image processing device according to one embodiment of the present invention; FIG. 2 is a block diagram of a transfer function module according to one embodiment of the present invention; FIG. 3 is a graph demonstrating two example transfer functions; FIG. 4 is a graph demonstrating partitioning a transfer function according to one embodiment of the present invention; FIG. 5 is a flow diagram of reprogramming a look-up table according to one embodiment of the present invention; and FIG. 6 is an architectural block diagram demonstrating image processing by an image processing device according to one embodiment of the present invention. DESCRIPTION Image Processing Device FIG. 1 shows an example generic image processing device (IPD) 100 in which embodiments of the present invention can be implemented. The IPD can be a digital camera (either one capable of only still photography, one capable of video capture, also known as a camcorder, or both), a cellular phone with imaging capabilities, a personal digital assistant (PDA) with imaging capabilities, a personal computer (PC), a mobile computer such as a laptop, or any other computing device with image processing capabilities. The IPD 100 need not poses image capturing capabilities, the image data can be fed from some source to the IPD 100 . In one embodiment, the IPD 100 includes a sensor 102 that can convert light into digital image data. The sensor 102 can be a Complementary Metal Oxide Semiconductor (CMOS) image sensor, a Charge Coupled Device (CCD)-type sensor, or any other sensor used for digital photography. The IPD 100 may further include any number of image data sources 104 , such as a processor or some memory that feeds image data onto the image data bus 106 . The image data bus 106 can carry image data output by the sensor 102 or other image data source 104 , in various formats, such as raw image data of any depth (e.g., 12 bit, 10 bit, 9 bit, 8 bit) or color space-specific pre-processed data, e.g., YcbCr or RGB data (8 bit). The image data can then undergo various image data processing. In one embodiment, if the image data is in a 9 or 10 bit format, the image data can be companded into an 8 bit format to increase processing speed, reduce the storage requirements, and decrease the memory bandwidth required to transfer the image to the targeted memory resources. A companding (compress-expand) operation can be performed using a transfer function. A transfer function maps inputs in the input range to outputs in the output range and describes the functioning of the appropriate system, in this case, the companding operation. The transfer function can be linear, but more often is represented by a curve. To increase processing speed, a transfer function can be represented by look-up table (LUT). A LUT can be an indexed data structure storing the outputs of the transfer function. The mapping of the transfer function can then be represented by an addressing scheme that maps the inputs to an index of the LUT, where the indexed output represents the output associated with the input by the transfer function. Transfer functions can also be used for gamma correction, compensating for sensor non-linearity, illumination correction, and various other image processing operations. In one embodiment, all required corrections can be implemented using a single transfer function. Thus, the image data from the image data bus 106 is further processed by the transfer function module (TFM) 108 , which maps the input image data to output image data according to a transfer function. Since transfer function can be used for various data processing operations, the TFM 108 has a generic name. However, in some embodiments, the TFM 108 could be referred to as a compand module, gamma correction module, and so on, according to specific functionality associated with the transfer function. In one embodiment, the image data is also observed by a histogram module 110 . The histogram module can tag colors and perform statistical analysis on the incoming image data to determine the appropriate transfer function to be used for the appropriate operations. Thus, in one embodiment, the histogram module 100 provides the information used to program the LUT(s) implementing the appropriate transfer function. How the appropriate transfer function is determined by the histogram module 110 is well understood by those skilled in the art. The IPD 100 can include various other components. In one embodiment, the IPD 100 includes a processor 112 controlling the operation of the IPD 100 , and a memory 114 to store an operating system and for storage to store the output of the TFM 108 . The IPD 100 can also have further processing modules 116 that process the image data further. The IPD 100 can also have a display 118 that can display the image data as an image to a user. The IPD 100 can also have various other components, such as a user interface, a radio transceiver, an audio input/output, and other hardware and software depending on the specific type of IPD 100 implemented. Transfer Functions Module One embodiment of the present invention is now described with reference to FIG. 2 . FIG. 2 shows an expanded view of the TFM 108 from FIG. 1 . The input of the TFM 108 is image data in any format, and the output of the TFM 108 is here generally referred to as transferred image data. This generic term is used, since in some embodiments, the output may be gamma corrected image data, companded image data, and so on. In one embodiment, the image data is first received by a color channel filter (CCF) 120 . The CCF 120 determines the color of the input data based on the image protocol being used. For example, for raw Bayer pattern RGB image data, the CCF 120 would know to expect red/green alternating for one image row, and green/blue alternating for the next image row. In one embodiment, the color of the input image data determines which LUT 124 to use. In FIG. 2 , there are three LUTs 124 shown for simplicity. The specific number of the LUTs depends, in one embodiment, on the number of colors (or other indicators such as hue or brightness) used by the color space of the image data. In one embodiment, the image data next enters the address module 122 . The address module 122 maps the image data to an index into the selected LUT 124 . In other words, the image data is used to address into the LUT 124 . The index, i.e., address, is mapped such that the LUT entry at the address is the output of the transfer function associated with the input image data. As mentioned above, in one embodiment, the LUT 124 does not contain all possible outputs in the output range of the transfer function. Instead, the transfer function is sampled. That is, the input range of the transfer function is divided into segments, and one sample input is chosen for each segment. For example, a sample input is chosen at every 6 th possible input over the input range. Then, the transfer function is calculated for these sample inputs, and these sample outputs can be stored in the LUT 124 . Some accuracy lost by sampling can be regained by passing sample output from the LUT 124 to an interpolation module 126 where some kind of interpolation can be performed to create an output value between two sample output values. Various interpolation techniques, including linear interpolation can be implemented by the interpolation module 126 . Look-Up Tables As discussed above, transfer functions are generally represented by a curve that maps the input range to the output range. When the curve is close to a straight line, i.e., has relatively low curvature, much of the accuracy lost by sampling can be regained using interpolation. However, when the curve is not straight or close to straight, i.e., has high curvature, interpolation cannot recapture some, or much, of the accuracy lost to sampling. The difference between high or low curvature can be dependent on error toleration factors, and can be expressed mathematically by the absolute value of the second order derivative of the transfer function. In one embodiment, a high curvature region is defined as one with an average curvature above a certain threshold, e.g., 5. Many real life transfer functions have both high-curvature and low-curvature portions, as shown in FIG. 3 . Since LUTs 124 are fixed in size, they can only store a certain number of samples. Since even a relatively few samples can accurately reflect the low-curvature regions of the transfer function, when used with interpolation, it can help accuracy to reallocate more of the fixed number of samples to the high-curvature regions of the transfer function. Thus, in one embodiment, the LUT 124 is re-programmable by the histogram module 110 to flexibly allocate more output samples to high-curvature regions. In one embodiment, the addressing scheme performed by the address module 122 takes account of this flexibility and properly maps the input image data to LUT addresses despite the flexibility of the LUT 124 . In one embodiment, the transfer function to be represented by the LUT 124 is divided into equal, or substantially equal regions over the input range. An embodiment using four quartile regions (or quartiles) is shown in FIG. 4 . Quartiles Q3 and Q4 are low curvature regions in which a low number of samples may be sufficient. However, quartiles Q1 and Q2 are higher-curvature regions, where accuracy can be significantly improved by using a more samples. The embodiments of the present invention are not limited to four such regions, more or less can be used as desired. One embodiment of re-programming the LUT 124 is now described with reference to FIG. 5 . In block 502 , a transfer function to be used for processing image data is generated. In one embodiment, this can be done according to known statistical methods. In block 504 , the input range of the transfer function is partitioned into regions. In one embodiment, the regions are substantially equal in size. There can be any number of regions. In three example embodiments there are two, four, and eight regions respectively. In block 506 , a determination is made as to whether any of the regions are high-curvature regions, as explained with reference to FIGS. 3 and 4 . In there are no high-curvature regions, the sample inputs are allocated uniformly across the various regions, in block 510 . However, if one or more regions are identified as high-curvature, then, in block 508 , more sample inputs are allocated to these high-curvature regions. In one embodiment, up to half (50 percent) of the regions can be designated as high-curvature. In one embodiment the number of input samples equals the number of possible entries in the LUT 124 . After all the input samples are allocated across the regions according to either block 508 or 510 , the transfer function is applied to the input samples, and the results (output samples) are used to populate the entries of the LUT 124 . Demonstrative Example One embodiment for a hardware implementation of the TFM 108 is now described with reference to FIG. 6 . In FIG. 6 , the image data from the image data bus 106 first passes through the CCF 120 . As described above, the CCF 120 determines the color of the image data and selects the appropriate LUT 124 based on this color. In this embodiment, the LUTs 124 are 48×8 bit tables, one for each color channel. Each 8-bit entry is an output sample of a transfer function implemented by the TFM 108 . In the embodiment shown in FIG. 6 , the CCF 120 also determines which quadrant the input image data belongs to. Depending on the quadrant, the CCF 120 divides the image data up into three fields, here referred descriptively as Q (quadrant), C (coarseness) and R (residue) fields. Non-descriptivelly, these fields can be referred to as first, second, and third parts or sections of the image data, respectively. Since there are four quadrants, two bits will identify the quadrant of the image data. Thus, the most significant two bits make up the Q field. The number of bits in the C field (here referred to as L Qi ) depends on the quadrant, and more specifically on how many samples were allocated to the particular quadrant. For example, if the input image data belongs to a quartile with 4 samples, the C field can have 2 bits. However, if the quartile has 8 samples, the C filed can have 3 bits. The bits not allocated to either Q or C fields are field R, the residual bits. The size of the R field depends on the size of the C field and the number of input bits in the image data. Multiplexer 128 uses the Q field to select the appropriate quartile pointer 130 , as indicated by the Q field. Upon the programming of the LUTs 124 , when the number of samples per quartile is set, the quartile pointers 130 are calculated, in one embodiment, as follows in Equations 1-4: Q 1-Pointer=base address of channel LUT  (Eq. 1) Q 2-Pointer=Q1-Pointer+2 L Q1   (Eq. 2) Q 3-Pointer= Q 1-Pointer+2 L Q1 +2 L Q2   (Eq. 3) Q 4-Pointer=Q1-Pointer+2 L Q1 +2 L Q2 +2 L Q3   (Eq. 4) where L Qi is the number of samples allocated to quartile number i. Thus, if the Q field places the input data image in quartile Q2, then multiplexer 128 selects the Q2-Pointer from the quartile pointers 130 . In one embodiment, multiplexer 132 selects the C field of the image data and merge 134 merges the selected quartile pointer with the C field to generate the index of the LUT entry. That is, the quartile pointer and the C field are combined to address into the selected LUT 124 . The entry corresponding the this index is referred to as E(i) in FIG. 6 . Next, interpolation is performed to produce the transferred image data. In one embodiment, the interpolation produces the result shown in Equation 5: Out ⁡ ( i ) = E ⁡ ( i ) + E ⁢ ( i + 1 ) - E ⁡ ( i ) 2 r · R ( Eq . ⁢ 5 ) where Out(i) is the output of the TFM 108 , i.e., the transferred image data, E(i+1) is the LUT entry after the indexed LUT entry, R is the binary value in the R field of the image data, and r is the number of bits in the R field. In one embodiment, arithmetic logic units 136 and 142 are used in conjunction with multiplier 138 and shift register 140 in the arrangement shown in FIG. 6 to perform the calculations required by Equation 5. General Matters Although the present system will be discussed with reference to various illustrated examples, these examples should not be read to limit the broader spirit and scope of the embodiments of the present invention. Some portions of the detailed description that follows are presented in terms of algorithms and symbolic representations of operations on data within a computer memory. These algorithmic descriptions and representations are the means used by those skilled in the computer science arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of operations or acts leading to a desired result. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers or the like. It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise, it will be appreciated that throughout the description of the embodiments of the present invention, use of terms such as “processing”, “computing”, “calculating”, “determining”, “displaying” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices. As indicated above, one embodiment of the present invention is instantiated in computer software, that is, computer readable instructions, which, when executed by one or more computer processors/systems, instruct the processors/systems to perform the designated actions. Such computer software may be resident in one or more computer readable media, such as hard drives, CD-ROMs, DVD-ROMs, read-only memory, read-write memory and so on. Such software may be distributed on one or more of these media, or may be made available for download across one or more computer networks (e.g., the Internet). Thus, a machine-readable medium includes any mechanism that provides (i.e., stores and/or transmits) information in a form accessible by a machine (e.g., a computer, network device, personal digital assistant, manufacturing tool, any device with a set of one or more processors, etc.). For example, a machine-accessible medium includes recordable/non-recordable media (e.g., read only memory (ROM); random access memory (RAM); magnetic disk storage media; optical storage media; flash memory devices; etc.), as well as electrical, optical, acoustical or other form of propagated signals (e.g., carrier waves, infrared signals, digital signals). Regardless of the format, the computer programming, rendering and processing techniques discussed herein are simply examples of the types of programming, rendering and processing techniques that may be used to implement aspects of the various embodiments of the present invention. These examples should in no way limit the embodiments of the present invention, which is best understood with reference to the claims that follow this description. Thus, an image processing device has been described. In the forgoing description, various specific values were given names, such as “image data” and “quartile pointer,” and various specific modules, such as the “interpolation module” and “transfer function module” have been described. However, these names are merely to describe and illustrate various aspects of the embodiments of the present invention, and in no way limit the scope of the embodiments of the present invention. Furthermore, various modules, such as the TFM 108 and the histogram module 110 in FIG. 1 , can be implemented as software or hardware modules, or without dividing their functionalities into modules at all. The embodiments of the present invention are not limited to any modular architecture either in software or in hardware, whether described above or not.
A system including an image data source and a transfer function module. The image data source is configured to provide image data. The transfer function module is configured to generate a transfer function to process the image data, define a first region of the transfer function, wherein a curvature of the transfer function in the first region is less than or equal to a threshold, define a second region of the transfer function, wherein a curvature of the transfer function in the second region is greater than the threshold, allocate a first number of sample inputs to the first region, allocate a second number of the sample inputs to the second region, wherein the second number is greater than the first number, map the sample inputs to sample outputs using the transfer function, and populate entries of a lookup table with the sample outputs.
Identify the most important claim in the given context and summarize it
[ "CROSS-REFERENCE TO RELATED APPLICATIONS The present disclosure is a divisional of U.S. patent application Ser.", "No. 10/812,626 (now U.S. Pat. No. 8,665,486), filed on Mar. 29, 2004.", "The entire disclosure of the application referenced above is incorporated herein by reference.", "FIELD Embodiments of the present invention relate generally to image data processing, and in particular, look-up tables used in image data processing.", "BACKGROUND Today, an ever-increasing number of mobile devices, such as PDAs and cellular telephones, are being outfitted with digital cameras and video recorders.", "Such digital cameras use sensors to which capture images in a digital data format, i.e., as bits;", "zeros and ones.", "Digital data processing involves manipulating these bits to enhance the resultant image, or for other purposes, such as convenient storage.", "There are numerous well-known image data processing operations that can be performed on digital image data.", "These include companding (reducing the bit-depth of the image data), gamma correction (compensating for brightness differences), sensor correction (compensating for sensor non-linearity), and illumination correction (compensating for changed illumination environment, e.g. inside or outside) to name a few.", "All of the data processing operations mentioned above may be implemented using a transfer function to describe the appropriate adjustment.", "A transfer function is merely a function that maps input values to output values according to a formula or curve.", "Transfer functions can be implemented in hardware as look-up tables (LUT) to increase processing speed.", "However, a full LUT representing all possible outputs of a transfer function takes up a lot of memory.", "One way to reduce the memory required to store the LUT is to have the LUT store only sample outputs of the transfer function.", "However, sampling the transfer function compromises accuracy and flexibility.", "BRIEF DESCRIPTION OF DRAWINGS Embodiments of the present invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements and in which: FIG. 1 is a block diagram of an image processing device according to one embodiment of the present invention;", "FIG. 2 is a block diagram of a transfer function module according to one embodiment of the present invention;", "FIG. 3 is a graph demonstrating two example transfer functions;", "FIG. 4 is a graph demonstrating partitioning a transfer function according to one embodiment of the present invention;", "FIG. 5 is a flow diagram of reprogramming a look-up table according to one embodiment of the present invention;", "and FIG. 6 is an architectural block diagram demonstrating image processing by an image processing device according to one embodiment of the present invention.", "DESCRIPTION Image Processing Device FIG. 1 shows an example generic image processing device (IPD) 100 in which embodiments of the present invention can be implemented.", "The IPD can be a digital camera (either one capable of only still photography, one capable of video capture, also known as a camcorder, or both), a cellular phone with imaging capabilities, a personal digital assistant (PDA) with imaging capabilities, a personal computer (PC), a mobile computer such as a laptop, or any other computing device with image processing capabilities.", "The IPD 100 need not poses image capturing capabilities, the image data can be fed from some source to the IPD 100 .", "In one embodiment, the IPD 100 includes a sensor 102 that can convert light into digital image data.", "The sensor 102 can be a Complementary Metal Oxide Semiconductor (CMOS) image sensor, a Charge Coupled Device (CCD)-type sensor, or any other sensor used for digital photography.", "The IPD 100 may further include any number of image data sources 104 , such as a processor or some memory that feeds image data onto the image data bus 106 .", "The image data bus 106 can carry image data output by the sensor 102 or other image data source 104 , in various formats, such as raw image data of any depth (e.g., 12 bit, 10 bit, 9 bit, 8 bit) or color space-specific pre-processed data, e.g., YcbCr or RGB data (8 bit).", "The image data can then undergo various image data processing.", "In one embodiment, if the image data is in a 9 or 10 bit format, the image data can be companded into an 8 bit format to increase processing speed, reduce the storage requirements, and decrease the memory bandwidth required to transfer the image to the targeted memory resources.", "A companding (compress-expand) operation can be performed using a transfer function.", "A transfer function maps inputs in the input range to outputs in the output range and describes the functioning of the appropriate system, in this case, the companding operation.", "The transfer function can be linear, but more often is represented by a curve.", "To increase processing speed, a transfer function can be represented by look-up table (LUT).", "A LUT can be an indexed data structure storing the outputs of the transfer function.", "The mapping of the transfer function can then be represented by an addressing scheme that maps the inputs to an index of the LUT, where the indexed output represents the output associated with the input by the transfer function.", "Transfer functions can also be used for gamma correction, compensating for sensor non-linearity, illumination correction, and various other image processing operations.", "In one embodiment, all required corrections can be implemented using a single transfer function.", "Thus, the image data from the image data bus 106 is further processed by the transfer function module (TFM) 108 , which maps the input image data to output image data according to a transfer function.", "Since transfer function can be used for various data processing operations, the TFM 108 has a generic name.", "However, in some embodiments, the TFM 108 could be referred to as a compand module, gamma correction module, and so on, according to specific functionality associated with the transfer function.", "In one embodiment, the image data is also observed by a histogram module 110 .", "The histogram module can tag colors and perform statistical analysis on the incoming image data to determine the appropriate transfer function to be used for the appropriate operations.", "Thus, in one embodiment, the histogram module 100 provides the information used to program the LUT(s) implementing the appropriate transfer function.", "How the appropriate transfer function is determined by the histogram module 110 is well understood by those skilled in the art.", "The IPD 100 can include various other components.", "In one embodiment, the IPD 100 includes a processor 112 controlling the operation of the IPD 100 , and a memory 114 to store an operating system and for storage to store the output of the TFM 108 .", "The IPD 100 can also have further processing modules 116 that process the image data further.", "The IPD 100 can also have a display 118 that can display the image data as an image to a user.", "The IPD 100 can also have various other components, such as a user interface, a radio transceiver, an audio input/output, and other hardware and software depending on the specific type of IPD 100 implemented.", "Transfer Functions Module One embodiment of the present invention is now described with reference to FIG. 2 .", "FIG. 2 shows an expanded view of the TFM 108 from FIG. 1 .", "The input of the TFM 108 is image data in any format, and the output of the TFM 108 is here generally referred to as transferred image data.", "This generic term is used, since in some embodiments, the output may be gamma corrected image data, companded image data, and so on.", "In one embodiment, the image data is first received by a color channel filter (CCF) 120 .", "The CCF 120 determines the color of the input data based on the image protocol being used.", "For example, for raw Bayer pattern RGB image data, the CCF 120 would know to expect red/green alternating for one image row, and green/blue alternating for the next image row.", "In one embodiment, the color of the input image data determines which LUT 124 to use.", "In FIG. 2 , there are three LUTs 124 shown for simplicity.", "The specific number of the LUTs depends, in one embodiment, on the number of colors (or other indicators such as hue or brightness) used by the color space of the image data.", "In one embodiment, the image data next enters the address module 122 .", "The address module 122 maps the image data to an index into the selected LUT 124 .", "In other words, the image data is used to address into the LUT 124 .", "The index, i.e., address, is mapped such that the LUT entry at the address is the output of the transfer function associated with the input image data.", "As mentioned above, in one embodiment, the LUT 124 does not contain all possible outputs in the output range of the transfer function.", "Instead, the transfer function is sampled.", "That is, the input range of the transfer function is divided into segments, and one sample input is chosen for each segment.", "For example, a sample input is chosen at every 6 th possible input over the input range.", "Then, the transfer function is calculated for these sample inputs, and these sample outputs can be stored in the LUT 124 .", "Some accuracy lost by sampling can be regained by passing sample output from the LUT 124 to an interpolation module 126 where some kind of interpolation can be performed to create an output value between two sample output values.", "Various interpolation techniques, including linear interpolation can be implemented by the interpolation module 126 .", "Look-Up Tables As discussed above, transfer functions are generally represented by a curve that maps the input range to the output range.", "When the curve is close to a straight line, i.e., has relatively low curvature, much of the accuracy lost by sampling can be regained using interpolation.", "However, when the curve is not straight or close to straight, i.e., has high curvature, interpolation cannot recapture some, or much, of the accuracy lost to sampling.", "The difference between high or low curvature can be dependent on error toleration factors, and can be expressed mathematically by the absolute value of the second order derivative of the transfer function.", "In one embodiment, a high curvature region is defined as one with an average curvature above a certain threshold, e.g., 5.", "Many real life transfer functions have both high-curvature and low-curvature portions, as shown in FIG. 3 .", "Since LUTs 124 are fixed in size, they can only store a certain number of samples.", "Since even a relatively few samples can accurately reflect the low-curvature regions of the transfer function, when used with interpolation, it can help accuracy to reallocate more of the fixed number of samples to the high-curvature regions of the transfer function.", "Thus, in one embodiment, the LUT 124 is re-programmable by the histogram module 110 to flexibly allocate more output samples to high-curvature regions.", "In one embodiment, the addressing scheme performed by the address module 122 takes account of this flexibility and properly maps the input image data to LUT addresses despite the flexibility of the LUT 124 .", "In one embodiment, the transfer function to be represented by the LUT 124 is divided into equal, or substantially equal regions over the input range.", "An embodiment using four quartile regions (or quartiles) is shown in FIG. 4 .", "Quartiles Q3 and Q4 are low curvature regions in which a low number of samples may be sufficient.", "However, quartiles Q1 and Q2 are higher-curvature regions, where accuracy can be significantly improved by using a more samples.", "The embodiments of the present invention are not limited to four such regions, more or less can be used as desired.", "One embodiment of re-programming the LUT 124 is now described with reference to FIG. 5 .", "In block 502 , a transfer function to be used for processing image data is generated.", "In one embodiment, this can be done according to known statistical methods.", "In block 504 , the input range of the transfer function is partitioned into regions.", "In one embodiment, the regions are substantially equal in size.", "There can be any number of regions.", "In three example embodiments there are two, four, and eight regions respectively.", "In block 506 , a determination is made as to whether any of the regions are high-curvature regions, as explained with reference to FIGS. 3 and 4 .", "In there are no high-curvature regions, the sample inputs are allocated uniformly across the various regions, in block 510 .", "However, if one or more regions are identified as high-curvature, then, in block 508 , more sample inputs are allocated to these high-curvature regions.", "In one embodiment, up to half (50 percent) of the regions can be designated as high-curvature.", "In one embodiment the number of input samples equals the number of possible entries in the LUT 124 .", "After all the input samples are allocated across the regions according to either block 508 or 510 , the transfer function is applied to the input samples, and the results (output samples) are used to populate the entries of the LUT 124 .", "Demonstrative Example One embodiment for a hardware implementation of the TFM 108 is now described with reference to FIG. 6 .", "In FIG. 6 , the image data from the image data bus 106 first passes through the CCF 120 .", "As described above, the CCF 120 determines the color of the image data and selects the appropriate LUT 124 based on this color.", "In this embodiment, the LUTs 124 are 48×8 bit tables, one for each color channel.", "Each 8-bit entry is an output sample of a transfer function implemented by the TFM 108 .", "In the embodiment shown in FIG. 6 , the CCF 120 also determines which quadrant the input image data belongs to.", "Depending on the quadrant, the CCF 120 divides the image data up into three fields, here referred descriptively as Q (quadrant), C (coarseness) and R (residue) fields.", "Non-descriptivelly, these fields can be referred to as first, second, and third parts or sections of the image data, respectively.", "Since there are four quadrants, two bits will identify the quadrant of the image data.", "Thus, the most significant two bits make up the Q field.", "The number of bits in the C field (here referred to as L Qi ) depends on the quadrant, and more specifically on how many samples were allocated to the particular quadrant.", "For example, if the input image data belongs to a quartile with 4 samples, the C field can have 2 bits.", "However, if the quartile has 8 samples, the C filed can have 3 bits.", "The bits not allocated to either Q or C fields are field R, the residual bits.", "The size of the R field depends on the size of the C field and the number of input bits in the image data.", "Multiplexer 128 uses the Q field to select the appropriate quartile pointer 130 , as indicated by the Q field.", "Upon the programming of the LUTs 124 , when the number of samples per quartile is set, the quartile pointers 130 are calculated, in one embodiment, as follows in Equations 1-4: Q 1-Pointer=base address of channel LUT (Eq.", "1) Q 2-Pointer=Q1-Pointer+2 L Q1 (Eq.", "2) Q 3-Pointer= Q 1-Pointer+2 L Q1 +2 L Q2 (Eq.", "3) Q 4-Pointer=Q1-Pointer+2 L Q1 +2 L Q2 +2 L Q3 (Eq.", "4) where L Qi is the number of samples allocated to quartile number i. Thus, if the Q field places the input data image in quartile Q2, then multiplexer 128 selects the Q2-Pointer from the quartile pointers 130 .", "In one embodiment, multiplexer 132 selects the C field of the image data and merge 134 merges the selected quartile pointer with the C field to generate the index of the LUT entry.", "That is, the quartile pointer and the C field are combined to address into the selected LUT 124 .", "The entry corresponding the this index is referred to as E(i) in FIG. 6 .", "Next, interpolation is performed to produce the transferred image data.", "In one embodiment, the interpolation produces the result shown in Equation 5: Out ⁡ ( i ) = E ⁡ ( i ) + E ⁢ ( i + 1 ) - E ⁡ ( i ) 2 r · R ( Eq .", "⁢ 5 ) where Out(i) is the output of the TFM 108 , i.e., the transferred image data, E(i+1) is the LUT entry after the indexed LUT entry, R is the binary value in the R field of the image data, and r is the number of bits in the R field.", "In one embodiment, arithmetic logic units 136 and 142 are used in conjunction with multiplier 138 and shift register 140 in the arrangement shown in FIG. 6 to perform the calculations required by Equation 5.", "General Matters Although the present system will be discussed with reference to various illustrated examples, these examples should not be read to limit the broader spirit and scope of the embodiments of the present invention.", "Some portions of the detailed description that follows are presented in terms of algorithms and symbolic representations of operations on data within a computer memory.", "These algorithmic descriptions and representations are the means used by those skilled in the computer science arts to most effectively convey the substance of their work to others skilled in the art.", "An algorithm is here, and generally, conceived to be a self-consistent sequence of operations or acts leading to a desired result.", "Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared and otherwise manipulated.", "It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers or the like.", "It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities.", "Unless specifically stated otherwise, it will be appreciated that throughout the description of the embodiments of the present invention, use of terms such as “processing”, “computing”, “calculating”, “determining”, “displaying”", "or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.", "As indicated above, one embodiment of the present invention is instantiated in computer software, that is, computer readable instructions, which, when executed by one or more computer processors/systems, instruct the processors/systems to perform the designated actions.", "Such computer software may be resident in one or more computer readable media, such as hard drives, CD-ROMs, DVD-ROMs, read-only memory, read-write memory and so on.", "Such software may be distributed on one or more of these media, or may be made available for download across one or more computer networks (e.g., the Internet).", "Thus, a machine-readable medium includes any mechanism that provides (i.e., stores and/or transmits) information in a form accessible by a machine (e.g., a computer, network device, personal digital assistant, manufacturing tool, any device with a set of one or more processors, etc.).", "For example, a machine-accessible medium includes recordable/non-recordable media (e.g., read only memory (ROM);", "random access memory (RAM);", "magnetic disk storage media;", "optical storage media;", "flash memory devices;", "etc.), as well as electrical, optical, acoustical or other form of propagated signals (e.g., carrier waves, infrared signals, digital signals).", "Regardless of the format, the computer programming, rendering and processing techniques discussed herein are simply examples of the types of programming, rendering and processing techniques that may be used to implement aspects of the various embodiments of the present invention.", "These examples should in no way limit the embodiments of the present invention, which is best understood with reference to the claims that follow this description.", "Thus, an image processing device has been described.", "In the forgoing description, various specific values were given names, such as “image data”", "and “quartile pointer,” and various specific modules, such as the “interpolation module”", "and “transfer function module”", "have been described.", "However, these names are merely to describe and illustrate various aspects of the embodiments of the present invention, and in no way limit the scope of the embodiments of the present invention.", "Furthermore, various modules, such as the TFM 108 and the histogram module 110 in FIG. 1 , can be implemented as software or hardware modules, or without dividing their functionalities into modules at all.", "The embodiments of the present invention are not limited to any modular architecture either in software or in hardware, whether described above or not." ]
CLAIM OF PRIORITY [0001] This application claims priority to an application entitled “ALIGNMENT APPARATUS FOR OPTICAL FIBER BLOCKS”, filed in the Korean Intellectual Property Office on Sep. 18, 2002 and assigned Serial No. 2002-56975, the contents of which are hereby incorporated by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to an optical communication device. More particularly, it relates to an alignment apparatus for connecting an optical fiber block to a planar optical wave-guide element. [0004] 2. Description of the Related Art [0005] In general, a planar optical wave-guide element has been used to divide many different wavelengths of optical signals advancing through a single optical path into respective single wavelengths of optical signals advancing through a plurality of optical paths. The planar optical wave-guide element includes at least one input terminal end and a plurality of output terminal ends so as to branch optical signals. There is included a core forming an optical wave-guide path between the input and output terminal ends to branch optical signals. The core is enclosed by a cladding material. Each of the input and output terminal ends is connected by an optical fiber, thus causing optical signals to be input or output. [0006] Typically, an optical fiber block is used to stably connect an optical fiber to the input or output terminal end of the planar optical wave-guide element. The optical block is adapted to arrange a single-cored optical fiber or a multiple-cored optical fiber into a V-shaped groove and then bond the optical fiber with an adhesive such as epoxy or the like, wherein the single-cored optical fiber has a single optical fiber strand, without an outer sheath on its terminal end, arranged into the V-shaped groove, but the multiple-cored optical fiber does generally take a ribbon form and has a plurality of optical fiber strands, without an outer sheath on its terminal end, arranged into the V-shaped groove. [0007] The optical fibers arranged on the optical fiber block as well as on the planar optical wave-guide element as mentioned above must be connected to each other with considerable precision. [0008] [0008]FIG. 1 is a perspective view of an alignment apparatus 100 for optical fiber blocks according to a conventional embodiment. FIG. 2 is a side view for describing the operation of the alignment apparatus 100 for optical fiber blocks shown in FIG. 1. As shown in FIGS. 1 and 2, an alignment apparatus 100 for optical fiber blocks in accordance with the conventional embodiment is mounted on an alignment driving actuator 190 and comprises a base plate 111 , a lower plate 113 , a upper plate 115 , a sliding table 117 , a jig 119 for locking an optical fiber block, a locking axle 127 , a locking driver 125 , and a displacement sensor 123 . [0009] The base plate 111 includes a first plate 111 a for mounting the alignment apparatus 100 for optical fiber blocks to the alignment driving actuator 190 , and a second plate 111 b extending in a direction perpendicular to the first plate 111 a . The lower plate 113 is mounted to the second plate 111 b. [0010] The lower plate 113 helps to guide the sliding table 117 to move horizontally in a forward or backward direction z, taking a folded form vertically extending from the opposite ends thereof so as not only to mount the locking driver 125 but also to restrict a movable range of the sliding table 117 . That is to say, the lower plate 113 is designed so that the movable range of the sliding table 117 is restricted by it and that both the locking driver 125 and the displacement sensor 123 are mounted to it. [0011] The sliding table 117 is intended to finely align an optical fiber block 101 which is locked to the jig 119 . When the optical fiber block 101 is locked to the jig 119 , the optical fiber block 101 is subjected to a resilient force from a certain resilient means 121 in a direction such that the optical fiber block 101 comes into a close contact to a corresponding counterpart component 102 such as the planar optical wave-guide element. The sliding table 117 is horizontally movable on the lower plate 113 and at the same time is subjected to restriction to the movable range thereof by the configuration of the lower plate 113 . [0012] The upper plate 115 is firmly mounted on the sliding table 117 so that it is possible for the upper plate to move together with the sliding table 117 . The upper plate 115 is also provided with the jig 119 . [0013] The jig 119 for locking the optical fiber block 101 includes a bracket 119 a for positioning the optical fiber block 101 and a holder 119 b for locking the optical fiber block 101 positioned by the bracket 119 a . The optical fiber block 101 positioned by the bracket 119 b is locked to protrude forward farther than both the lower plate 113 and the upper plate 115 . [0014] The locking axle 127 , the locking driver 125 and the displacement sensor 123 are installed on the folded part 113 a vertically extending from a rear end of the lower plate 113 . Therefore, the sliding table 117 is locked when displacement of the sliding table 117 aligns the optical fiber block 101 in the optimal position. That is to say, the optical fiber block 101 comes into close contact with the counterpart component, such as a planar optical wave-guide element or the like. An end surface of the optical fiber block 101 is aligned parallel to an end surface of the counterpart component. At this position, the sliding table 117 is located at a forefront while the optical fiber block 101 is aligned, whereby the position is sensed by the displacement sensor 123 . The locking driver 125 moves the locking axle 127 forward, and thereby locks the upper plate 115 . [0015] The alignment apparatus 100 for optical fiber blocks as mentioned above is mounted on the alignment driving actuator 190 . [0016] The alignment driving actuator 190 provides the optical fiber block 101 with three dimensional linear and rotational alignments in relation with a x-axis, a y-axis and a z-axis, respectively, wherein the linear alignments are performed along to the respective x-, y- and z-axes, i.e. in a left or right direction x, in an upward or downward direction y, and in a forward or backward direction z; whereas the rotational alignments are performed about the respective x-, y- and z-axes, i.e. in a x-axial rotational direction θx, in a y-axial rotational direction θy, and in a z-axial rotational direction θz. [0017] Referring to FIG. 2, the linear alignments of all the x-, y- and z-axes and the rotational alignment for the z-axis are performed by a lower driving actuator 191 . The rotational alignments of the x- and y-axes are performed by first and second upper driving actuators 197 and 199 . The lower driving actuator 191 first performs an approximate alignment first and then the upper driving actuators 197 and 199 perform a fine alignment. [0018] Also, for alignments of the three axial linear directions x, y and z, respectively, and three axial rotational directions θx, θy and θz, driving motors are required corresponding to each of the directions. Particularly, for respective fine alignments of the x and y axial rotational directions θx and θy, respectively, driving motors with high precision are required. [0019] Despite these high precision driving motors, the conventional alignment apparatus is flawed in that the motors perform alignment of the x- and y-axial rotational directions, θx and θy respectively, individually, resulting is poor alignment with respect to one another. Moreover, the bracket on which the optical fiber block is positioned is manufactured corresponding to the size of the optical fiber block. Consequently, the bracket should be replaced in order to align another optical fiber block on which another cored optical fiber is arranged. SUMMARY OF THE INVENTION [0020] Accordingly, there is a need to provide an alignment apparatus that can perform its intended purpose efficiently with more precision and less expense. [0021] According to one aspect of the invention, a jig that freely rotates about the axis running through the center of the fiber optic block is provided and serves as the alignment means about the y rotational axis, and further provides for simultaneous alignment of the x and y rotational axes providing a higher magnitude of precision. The jig eliminates the need for a separate driving motor for the alignment of the y rotational axis reducing the manufacturing cost of the apparatus. [0022] According to another aspect of the invention, a jig is provided with a supporting part that traverses on the holding part, thereby permitting the use of fiber optic blocks of different sizes on the same jig and decreasing manufacturing costs as only one jig is needed to perform the alignment for any size of fiber optic block. [0023] Accordingly, there is provided an alignment apparatus for optical fiber blocks for aligning a planar optical wave-guide element and an optical fiber block, comprising: a lower plate; a sliding table mounted on the lower plate capable of horizontal displacement on the lower plate; an upper plate mounted to the sliding table; and, a jig disposed on the upper plate and fixed to rotational means capable of rotation about the upper plate for holding the optical fiber block. BRIEF DESCRIPTION OF THE DRAWINGS [0024] The above and other features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: [0025] [0025]FIG. 1 is a perspective view of an alignment apparatus for optical fiber blocks according to a conventional embodiment; [0026] [0026]FIG. 2 is a side view for describing operation of the alignment apparatus for optical fiber blocks shown in FIG. 1; [0027] [0027]FIG. 3 is a perspective view of an alignment apparatus for optical fiber blocks according to a preferred embodiment of the present invention; [0028] [0028]FIG. 4 is a side view of the alignment apparatus for optical fiber blocks shown in FIG. 3; [0029] [0029]FIG. 5 is a perspective view showing a state in that a jig is eliminated from the alignment apparatus for optical fiber blocks shown in FIG. 3; [0030] [0030]FIG. 6 is a perspective view of a jig of the alignment apparatus for optical fiber blocks shown in FIG. 3; [0031] [0031]FIG. 7 is a perspective view of a bracket of the jig shown in FIG. 6; and, [0032] [0032]FIG. 8 is a side view for describing operation of the alignment apparatus for optical fiber blocks shown in FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0033] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. For the purposes of clarity and simplicity, a detailed description of known functions and configurations incorporated herein ill be omitted as they would obscure the invention in unnecessary detail. [0034] [0034]FIG. 3 is a perspective view of an alignment apparatus 200 for optical fiber blocks according to a preferred embodiment of the present invention. FIG. 4 is a side view of an alignment apparatus 200 for optical fiber blocks as shown in FIG. 3. As shown in FIGS. 3 and 4, an alignment apparatus 200 for optical fiber blocks according to a preferred embodiment of the present invention comprises a base plate 211 , a lower plate 213 , a sliding table 217 , an upper plate 215 , a jig 219 for locking an optical fiber block, a locking axle 227 , a locking driver 225 and a displacement sensor 223 . The alignment apparatus 200 is mounted on an alignment driving actuator 290 , as shown in FIG. 8. [0035] The base plate 211 extend vertically upward at one end where it is mounted to the alignment driving actuator 290 of the alignment apparatus 200 . The lower plate 213 is mounted to the base plate 211 . [0036] The lower plate 213 acts as a guide for the sliding table 217 to move horizontally thereon in a forward and backward direction z. Both ends of lower plate 213 protrude perpendicularly upward in direction y so that one end serves to mount the locking driver 225 , locking axle 227 , and the displacement sensor 223 therethrough. Another consequence of the lower plate 213 having such a configuration is to restrict the displacement of the sliding table 217 thereon. That is, the vertical ends act as stops or side walls for the sliding table 217 . The upper plate 215 is rigidly mounted on the sliding table 217 so that they are both displaced horizontally simultaneously with respect to the lower plate 213 . The upper plate 215 is constructed having an L-shape. It is fixed to the sliding table 217 so that one portion of the upper plate 215 lays flat on the top surface of the sliding table 217 and the other end is perpendicular to that portion and extends downward in a y direction so as to come between the sliding table 217 on one side and the locking axle 227 , the locking driver 225 , and displacement sensor 223 on the other side. The upper plate 215 is provided with the jig 219 attached thereon. [0037] A resilient means 221 for providing a resilient force upon the sliding table 217 is fitted between the side wall of the lower plate 213 having the locking driver 225 , locking axle 227 , and displacement sensor 223 mounted therethrough, and the portion of the upper plate 215 extending downward in a y direction. The resilient force acts on the upper plate in the z direction displacing the upper plate, the sliding table 217 , and the jig 219 in the same direction. Consequently, the optical fiber block 201 which is locked in the jig 219 comes into close contact with a corresponding counterpart component, for example the planar optical wave-guide element. [0038] As shown in FIG. 6, the jig 219 for locking the optical fiber block includes a bracket 219 a for positioning the optical fiber block 201 and a holder 219 b for locking the optical fiber block 201 positioned by the bracket 219 a . The jig 219 is mounted in a horizontal plane on the upper plate 215 so that the jig can rotate in a y-axial rotational direction θy. In one embodiment of this invention as shown in FIG. 5, a bearing 231 and a rotation shaft 233 are mounted in the upper plate 215 , as shown in FIG. 5. The bearing 231 is press-fitted into the upper plate 215 . The rotation shaft 233 is rotatably connected to the bearing 231 extending axially through the upper plate 215 . The rotation shaft 233 protrudes above the upper plate 215 . The jig 219 is mounted on the protruded end of the rotation shaft 233 . This feature eliminates the need for a precision driving motor to align the jig 219 about the y axis. The optical fiber block 201 is preferably locked on the bracket 219 a in a state such that the optical fiber block extends beyond the lower and upper plates 213 and 215 . [0039] In another embodiment of this invention as shown in FIG. 7, the bracket 219 a comprises a locking part 21 and a supporting part 23 . The locking part 21 provides a surface upon which the optical fiber block 201 is placed, while the supporting part 23 supports one end of the optical fiber block 201 . The size of an optical fiber block 201 varies depending on the number of optical fiber strand arranged on the optical fiber block 201 . Consequently, since the size of different optical fiber blocks 201 may vary, the supporting part 23 may shift its horizontal position on the locking part 21 accordingly to accommodate a range of sizes of optical fiber blocks 201 . This feature results in using one bracket 219 a for a range of optical fiber blocks 201 of different sizes. This eliminates the disadvantage of a conventional alignment apparatus for optical fiber blocks wherein the bracket must be replaced every time an optical fiber block of a different size is to be aligned. [0040] Describing the operation of the components of the alignment apparatus 200 for optical fiber blocks according to the embodiments of this invention, the resilient force applied by the resilient means 221 is applied against the portion of the upper plate 215 extending perpendicular to it. This force results in the linear displacement of the upper plate 215 . As the upper plate 215 is fixed to the jig by means of the rotation shaft 233 , the jig 219 is also displaced by the same magnitude in the z horizontal direction. The displacement of the upper plate 215 and jig 219 are restricted in all other linear directions due to the fact that the upper plate 215 is rigidly fixed to the sliding table which is constrained to displacement only in the linear z direction. As these components are displaced, the optical fiber block 201 loaded in the jig comes into close contact with the corresponding counterpart component, such as the planar optical wave-guide element. An end surface of the optical fiber block 101 is aligned parallel to an end surface of the counterpart component. There, the sliding table 217 is at maximum displacement. As the optical fiber block 201 comes into close contact with the counterpart component, the jig 219 pivots about the rotation shaft 233 aligning itself automatically. The optical fiber block 201 is aligned in the optimal position when the sliding table 217 is displaced to its maximum extent. Thereafter, the displacement sensor 223 senses this maximum displacement generating a signal causing the locking driver 225 to drive the locking axle 227 to lock the upper plate 215 in its current position. Consequently, the jig 219 is also prevented from further linear displacement thus preventing any further rotation about the rotation shaft 233 . [0041] In another embodiment of this invention, the jig 219 may be provided with a spherical member 229 positioned so that it comes into contact with the locking axle 227 when the locking driver 225 drives the locking axle 227 forward to lock the jig 219 in the optimum position. This spherical member 229 is to uniformly distribute a locking force upon the jig 219 when one end of the locking axle 227 comes into contact with it. In one embodiment of this invention and as shown in FIG. 5, two vertical pegs 240 extending vertically upwards in a y direction formed on the top surface of the top plate form the rotational limits that the jig 219 may rotate about the y axis. These pegs limit the rotation and act as stops for the jig 219 when the spherical member 229 come into contact with them. This assures that the spherical member 229 does not rotate outside the range where the locking axle 227 may come into contact with it when it is driven by the locking driver 225 . [0042] The alignment apparatus 200 for optical fiber blocks as described in the invention is mounted on the alignment driving actuator 290 that enables the jig 219 to pivot about a y rotational axis θy, so that the alignment apparatus does not require a separate driving motor for alignment in the y rotational axis θy, unlike the conventional alignment apparatus. [0043] The alignment driving actuator 290 requires three dimensional linear and rotational alignments in relation with a x-axis, a y-axis and a z-axis, respectively, where the linear alignments are performed along to the respective x-, y- and z-axes, i.e. in a left or right direction x, in an upward or downward direction y, and in a forward or backward direction z; whereas the rotational alignments are performed about the respective x-, y- and z-axes, i.e. about a x rotational axis Ox, about a y rotational axis θy, and about a z rotational axis θz. The linear alignments in all the x-, y- and z-axes and the rotational alignment about the z rotational axis are performed by a lower driving actuator 291 , and the rotational alignments to the x-axis is performed by an upper driving actuator 299 . [0044] To align the optical fiber block using the alignment apparatus 200 , the lower driving actuator 291 performs an approximate alignment first and then the upper driving actuator 299 performs a fine alignment. The alignment about the y rotational axis θy is automatically performed at the moment when the optical fiber block 201 contacts the counterpart component and the jig 219 rotates about the rotation shaft 233 . [0045] Opposingly, in the conventional alignment apparatus for optical fiber blocks 100 , the y axis of rotation θy is located on the rear side of the base plate 111 (see FIG. 1) and is spaced apart from the optical fiber block to a certain extent. Therefore, even a fine operation of the driving motor about the x rotational axis θx results in an increasing displacement of the optical fiber block because of the distance between the y axis of rotation θy and the optical fiber block. The conventional apparatus thus requires the driving motor to be operated with high precision. [0046] To the contrary, the alignment apparatus 200 for optical fiber blocks of this invention provides a y axis of rotation θy located through the position where the optical fiber block 201 is locked. This occurs due to the axis of the rotational shaft 233 that the jig 233 rotates about being located through the c enter of the optical fiber block 201 locked position. Therefore, it is easy to adjust a displacement of the optical fiber block 201 finely during the alignment of the optical fiber block. Moreover, it is possible to simultaneously perform the alignment about the y and x axes of rotation, θy and θx, because as a resilient force is applied in a direction in which the optical fiber block 201 contacts the counterpart component, the rotation shaft 233 and bearing 231 provide a rotational means for the jig. [0047] In the embodiments of the present invention as shown in FIG. 8, the following is a description of the procedure for aligning an optical fiber block using the alignment apparatus 200 for optical fiber blocks. The optical fiber block 201 is positioned on the alignment apparatus 200 , wherein the alignment apparatus 200 is mounted on the alignment driving actuator 290 . Here, the bracket 219 a is adjusted to accommodate the size of the optical fiber block 201 . When the optical fiber block 201 is positioned, the lower driving actuator 291 is operated to perform linear alignments initially for the x- and y-axial directions and the rotational alignment about the z rotational axis and then to advance the alignment apparatus 200 toward the counterpart component 202 , such as the planar wave-guide element, in the z-axial direction. [0048] When the alignment apparatus 200 advances coming into contact with the optical fiber block 201 , the lower driving actuator 291 causes the optical fiber block 201 to advance to a predetermined extent. As the optical fiber block 201 makes contact with the counterpart component, the resulting reaction force of the counterpart component 202 forces the jig 219 , upper plate 215 , and sliding table 217 in the opposite linear z direction relative to the displacement of the alignment apparatus 200 . It will be apparent that advancement of the alignment apparatus 200 by the lower driving actuator 291 should be limited to a displacement no greater than the maximum traveling range of the sliding table 217 on the lower plate 213 once the optical fiber block 201 makes contact with the counterpart component 202 . As the sliding table 217 , upper plate 215 , and jig 219 move in the opposite direction relative to the movement of the alignment apparatus 200 , a resilient force from the resilient means 221 acts upon the upper plate 215 and ultimately the jig 219 and the sliding table 217 as well. The reaction of the forces acting between the optical fiber block 201 and the counterpart component 202 causes the jig 219 to rotate about the y rotational axis θy. The jig 219 continues to rotate freely from the point when the optical fiber block 201 comes into contact with the counterpart component 202 until the point when the alignment is completed. [0049] After the alignment apparatus 200 is advanced to a proper position, the alignment about the x rotational axis θx is performed by the upper driving actuator 299 . At this point, the jig 219 also continues to rotate freely about the y rotational axis θy. This configuration efficiently provides for the precise and simultaneous alignment about both x and y axes rotational axes, θx and θy, without the need for an independent driving motor for alignment about the y axis of rotation. At such time when the optical fiber block 201 makes contact with the counterpart component, the displacement sensor 223 senses the position where the sliding table 217 is advanced to a maximum displacement., At such time the alignment of the optical fiber block 201 is complete and the locking driver 225 causes the locking axle 227 to be advanced. In one embodiment of this invention the locking axle 227 advances and makes contact with the upper plate 215 preventing any further linear movement of the upper plate 215 , sliding table 217 , and jig 219 . This also restricts the jig 219 from any further rotation about rotational shaft 233 . In another embodiment the locking axle 227 advances towards the spherical member 229 provided with the jig 219 . Once contact is made the spherical member locks the jig 219 in place preventing it from further advancement or rotation and also preventing further advancement of the upper plate 215 and sliding table 217 . [0050] While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
This invention relates to an alignment apparatus for aligning a planar optical wave-guide element and an optical fiber block wherein alignment can be completed with more precision and less expense than conventional methods. The alignment apparatus comprising a lower plate; a sliding table mounted on the lower plate capable of horizontal displacement on the lower plate; an upper plate mounted to the sliding table; and, a jig disposed on the upper plate and fixed to rotational means and capable of rotation about the upper plate for holding the optical fiber block.
Identify and summarize the most critical technical features from the given patent document.
[ "CLAIM OF PRIORITY [0001] This application claims priority to an application entitled “ALIGNMENT APPARATUS FOR OPTICAL FIBER BLOCKS”, filed in the Korean Intellectual Property Office on Sep. 18, 2002 and assigned Serial No. 2002-56975, the contents of which are hereby incorporated by reference.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] The present invention relates to an optical communication device.", "More particularly, it relates to an alignment apparatus for connecting an optical fiber block to a planar optical wave-guide element.", "[0004] 2.", "Description of the Related Art [0005] In general, a planar optical wave-guide element has been used to divide many different wavelengths of optical signals advancing through a single optical path into respective single wavelengths of optical signals advancing through a plurality of optical paths.", "The planar optical wave-guide element includes at least one input terminal end and a plurality of output terminal ends so as to branch optical signals.", "There is included a core forming an optical wave-guide path between the input and output terminal ends to branch optical signals.", "The core is enclosed by a cladding material.", "Each of the input and output terminal ends is connected by an optical fiber, thus causing optical signals to be input or output.", "[0006] Typically, an optical fiber block is used to stably connect an optical fiber to the input or output terminal end of the planar optical wave-guide element.", "The optical block is adapted to arrange a single-cored optical fiber or a multiple-cored optical fiber into a V-shaped groove and then bond the optical fiber with an adhesive such as epoxy or the like, wherein the single-cored optical fiber has a single optical fiber strand, without an outer sheath on its terminal end, arranged into the V-shaped groove, but the multiple-cored optical fiber does generally take a ribbon form and has a plurality of optical fiber strands, without an outer sheath on its terminal end, arranged into the V-shaped groove.", "[0007] The optical fibers arranged on the optical fiber block as well as on the planar optical wave-guide element as mentioned above must be connected to each other with considerable precision.", "[0008] [0008 ]FIG. 1 is a perspective view of an alignment apparatus 100 for optical fiber blocks according to a conventional embodiment.", "FIG. 2 is a side view for describing the operation of the alignment apparatus 100 for optical fiber blocks shown in FIG. 1. As shown in FIGS. 1 and 2, an alignment apparatus 100 for optical fiber blocks in accordance with the conventional embodiment is mounted on an alignment driving actuator 190 and comprises a base plate 111 , a lower plate 113 , a upper plate 115 , a sliding table 117 , a jig 119 for locking an optical fiber block, a locking axle 127 , a locking driver 125 , and a displacement sensor 123 .", "[0009] The base plate 111 includes a first plate 111 a for mounting the alignment apparatus 100 for optical fiber blocks to the alignment driving actuator 190 , and a second plate 111 b extending in a direction perpendicular to the first plate 111 a .", "The lower plate 113 is mounted to the second plate 111 b. [0010] The lower plate 113 helps to guide the sliding table 117 to move horizontally in a forward or backward direction z, taking a folded form vertically extending from the opposite ends thereof so as not only to mount the locking driver 125 but also to restrict a movable range of the sliding table 117 .", "That is to say, the lower plate 113 is designed so that the movable range of the sliding table 117 is restricted by it and that both the locking driver 125 and the displacement sensor 123 are mounted to it.", "[0011] The sliding table 117 is intended to finely align an optical fiber block 101 which is locked to the jig 119 .", "When the optical fiber block 101 is locked to the jig 119 , the optical fiber block 101 is subjected to a resilient force from a certain resilient means 121 in a direction such that the optical fiber block 101 comes into a close contact to a corresponding counterpart component 102 such as the planar optical wave-guide element.", "The sliding table 117 is horizontally movable on the lower plate 113 and at the same time is subjected to restriction to the movable range thereof by the configuration of the lower plate 113 .", "[0012] The upper plate 115 is firmly mounted on the sliding table 117 so that it is possible for the upper plate to move together with the sliding table 117 .", "The upper plate 115 is also provided with the jig 119 .", "[0013] The jig 119 for locking the optical fiber block 101 includes a bracket 119 a for positioning the optical fiber block 101 and a holder 119 b for locking the optical fiber block 101 positioned by the bracket 119 a .", "The optical fiber block 101 positioned by the bracket 119 b is locked to protrude forward farther than both the lower plate 113 and the upper plate 115 .", "[0014] The locking axle 127 , the locking driver 125 and the displacement sensor 123 are installed on the folded part 113 a vertically extending from a rear end of the lower plate 113 .", "Therefore, the sliding table 117 is locked when displacement of the sliding table 117 aligns the optical fiber block 101 in the optimal position.", "That is to say, the optical fiber block 101 comes into close contact with the counterpart component, such as a planar optical wave-guide element or the like.", "An end surface of the optical fiber block 101 is aligned parallel to an end surface of the counterpart component.", "At this position, the sliding table 117 is located at a forefront while the optical fiber block 101 is aligned, whereby the position is sensed by the displacement sensor 123 .", "The locking driver 125 moves the locking axle 127 forward, and thereby locks the upper plate 115 .", "[0015] The alignment apparatus 100 for optical fiber blocks as mentioned above is mounted on the alignment driving actuator 190 .", "[0016] The alignment driving actuator 190 provides the optical fiber block 101 with three dimensional linear and rotational alignments in relation with a x-axis, a y-axis and a z-axis, respectively, wherein the linear alignments are performed along to the respective x-, y- and z-axes, i.e. in a left or right direction x, in an upward or downward direction y, and in a forward or backward direction z;", "whereas the rotational alignments are performed about the respective x-, y- and z-axes, i.e. in a x-axial rotational direction θx, in a y-axial rotational direction θy, and in a z-axial rotational direction θz.", "[0017] Referring to FIG. 2, the linear alignments of all the x-, y- and z-axes and the rotational alignment for the z-axis are performed by a lower driving actuator 191 .", "The rotational alignments of the x- and y-axes are performed by first and second upper driving actuators 197 and 199 .", "The lower driving actuator 191 first performs an approximate alignment first and then the upper driving actuators 197 and 199 perform a fine alignment.", "[0018] Also, for alignments of the three axial linear directions x, y and z, respectively, and three axial rotational directions θx, θy and θz, driving motors are required corresponding to each of the directions.", "Particularly, for respective fine alignments of the x and y axial rotational directions θx and θy, respectively, driving motors with high precision are required.", "[0019] Despite these high precision driving motors, the conventional alignment apparatus is flawed in that the motors perform alignment of the x- and y-axial rotational directions, θx and θy respectively, individually, resulting is poor alignment with respect to one another.", "Moreover, the bracket on which the optical fiber block is positioned is manufactured corresponding to the size of the optical fiber block.", "Consequently, the bracket should be replaced in order to align another optical fiber block on which another cored optical fiber is arranged.", "SUMMARY OF THE INVENTION [0020] Accordingly, there is a need to provide an alignment apparatus that can perform its intended purpose efficiently with more precision and less expense.", "[0021] According to one aspect of the invention, a jig that freely rotates about the axis running through the center of the fiber optic block is provided and serves as the alignment means about the y rotational axis, and further provides for simultaneous alignment of the x and y rotational axes providing a higher magnitude of precision.", "The jig eliminates the need for a separate driving motor for the alignment of the y rotational axis reducing the manufacturing cost of the apparatus.", "[0022] According to another aspect of the invention, a jig is provided with a supporting part that traverses on the holding part, thereby permitting the use of fiber optic blocks of different sizes on the same jig and decreasing manufacturing costs as only one jig is needed to perform the alignment for any size of fiber optic block.", "[0023] Accordingly, there is provided an alignment apparatus for optical fiber blocks for aligning a planar optical wave-guide element and an optical fiber block, comprising: a lower plate;", "a sliding table mounted on the lower plate capable of horizontal displacement on the lower plate;", "an upper plate mounted to the sliding table;", "and, a jig disposed on the upper plate and fixed to rotational means capable of rotation about the upper plate for holding the optical fiber block.", "BRIEF DESCRIPTION OF THE DRAWINGS [0024] The above and other features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: [0025] [0025 ]FIG. 1 is a perspective view of an alignment apparatus for optical fiber blocks according to a conventional embodiment;", "[0026] [0026 ]FIG. 2 is a side view for describing operation of the alignment apparatus for optical fiber blocks shown in FIG. 1;", "[0027] [0027 ]FIG. 3 is a perspective view of an alignment apparatus for optical fiber blocks according to a preferred embodiment of the present invention;", "[0028] [0028 ]FIG. 4 is a side view of the alignment apparatus for optical fiber blocks shown in FIG. 3;", "[0029] [0029 ]FIG. 5 is a perspective view showing a state in that a jig is eliminated from the alignment apparatus for optical fiber blocks shown in FIG. 3;", "[0030] [0030 ]FIG. 6 is a perspective view of a jig of the alignment apparatus for optical fiber blocks shown in FIG. 3;", "[0031] [0031 ]FIG. 7 is a perspective view of a bracket of the jig shown in FIG. 6;", "and, [0032] [0032 ]FIG. 8 is a side view for describing operation of the alignment apparatus for optical fiber blocks shown in FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0033] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.", "For the purposes of clarity and simplicity, a detailed description of known functions and configurations incorporated herein ill be omitted as they would obscure the invention in unnecessary detail.", "[0034] [0034 ]FIG. 3 is a perspective view of an alignment apparatus 200 for optical fiber blocks according to a preferred embodiment of the present invention.", "FIG. 4 is a side view of an alignment apparatus 200 for optical fiber blocks as shown in FIG. 3. As shown in FIGS. 3 and 4, an alignment apparatus 200 for optical fiber blocks according to a preferred embodiment of the present invention comprises a base plate 211 , a lower plate 213 , a sliding table 217 , an upper plate 215 , a jig 219 for locking an optical fiber block, a locking axle 227 , a locking driver 225 and a displacement sensor 223 .", "The alignment apparatus 200 is mounted on an alignment driving actuator 290 , as shown in FIG. 8. [0035] The base plate 211 extend vertically upward at one end where it is mounted to the alignment driving actuator 290 of the alignment apparatus 200 .", "The lower plate 213 is mounted to the base plate 211 .", "[0036] The lower plate 213 acts as a guide for the sliding table 217 to move horizontally thereon in a forward and backward direction z. Both ends of lower plate 213 protrude perpendicularly upward in direction y so that one end serves to mount the locking driver 225 , locking axle 227 , and the displacement sensor 223 therethrough.", "Another consequence of the lower plate 213 having such a configuration is to restrict the displacement of the sliding table 217 thereon.", "That is, the vertical ends act as stops or side walls for the sliding table 217 .", "The upper plate 215 is rigidly mounted on the sliding table 217 so that they are both displaced horizontally simultaneously with respect to the lower plate 213 .", "The upper plate 215 is constructed having an L-shape.", "It is fixed to the sliding table 217 so that one portion of the upper plate 215 lays flat on the top surface of the sliding table 217 and the other end is perpendicular to that portion and extends downward in a y direction so as to come between the sliding table 217 on one side and the locking axle 227 , the locking driver 225 , and displacement sensor 223 on the other side.", "The upper plate 215 is provided with the jig 219 attached thereon.", "[0037] A resilient means 221 for providing a resilient force upon the sliding table 217 is fitted between the side wall of the lower plate 213 having the locking driver 225 , locking axle 227 , and displacement sensor 223 mounted therethrough, and the portion of the upper plate 215 extending downward in a y direction.", "The resilient force acts on the upper plate in the z direction displacing the upper plate, the sliding table 217 , and the jig 219 in the same direction.", "Consequently, the optical fiber block 201 which is locked in the jig 219 comes into close contact with a corresponding counterpart component, for example the planar optical wave-guide element.", "[0038] As shown in FIG. 6, the jig 219 for locking the optical fiber block includes a bracket 219 a for positioning the optical fiber block 201 and a holder 219 b for locking the optical fiber block 201 positioned by the bracket 219 a .", "The jig 219 is mounted in a horizontal plane on the upper plate 215 so that the jig can rotate in a y-axial rotational direction θy.", "In one embodiment of this invention as shown in FIG. 5, a bearing 231 and a rotation shaft 233 are mounted in the upper plate 215 , as shown in FIG. 5. The bearing 231 is press-fitted into the upper plate 215 .", "The rotation shaft 233 is rotatably connected to the bearing 231 extending axially through the upper plate 215 .", "The rotation shaft 233 protrudes above the upper plate 215 .", "The jig 219 is mounted on the protruded end of the rotation shaft 233 .", "This feature eliminates the need for a precision driving motor to align the jig 219 about the y axis.", "The optical fiber block 201 is preferably locked on the bracket 219 a in a state such that the optical fiber block extends beyond the lower and upper plates 213 and 215 .", "[0039] In another embodiment of this invention as shown in FIG. 7, the bracket 219 a comprises a locking part 21 and a supporting part 23 .", "The locking part 21 provides a surface upon which the optical fiber block 201 is placed, while the supporting part 23 supports one end of the optical fiber block 201 .", "The size of an optical fiber block 201 varies depending on the number of optical fiber strand arranged on the optical fiber block 201 .", "Consequently, since the size of different optical fiber blocks 201 may vary, the supporting part 23 may shift its horizontal position on the locking part 21 accordingly to accommodate a range of sizes of optical fiber blocks 201 .", "This feature results in using one bracket 219 a for a range of optical fiber blocks 201 of different sizes.", "This eliminates the disadvantage of a conventional alignment apparatus for optical fiber blocks wherein the bracket must be replaced every time an optical fiber block of a different size is to be aligned.", "[0040] Describing the operation of the components of the alignment apparatus 200 for optical fiber blocks according to the embodiments of this invention, the resilient force applied by the resilient means 221 is applied against the portion of the upper plate 215 extending perpendicular to it.", "This force results in the linear displacement of the upper plate 215 .", "As the upper plate 215 is fixed to the jig by means of the rotation shaft 233 , the jig 219 is also displaced by the same magnitude in the z horizontal direction.", "The displacement of the upper plate 215 and jig 219 are restricted in all other linear directions due to the fact that the upper plate 215 is rigidly fixed to the sliding table which is constrained to displacement only in the linear z direction.", "As these components are displaced, the optical fiber block 201 loaded in the jig comes into close contact with the corresponding counterpart component, such as the planar optical wave-guide element.", "An end surface of the optical fiber block 101 is aligned parallel to an end surface of the counterpart component.", "There, the sliding table 217 is at maximum displacement.", "As the optical fiber block 201 comes into close contact with the counterpart component, the jig 219 pivots about the rotation shaft 233 aligning itself automatically.", "The optical fiber block 201 is aligned in the optimal position when the sliding table 217 is displaced to its maximum extent.", "Thereafter, the displacement sensor 223 senses this maximum displacement generating a signal causing the locking driver 225 to drive the locking axle 227 to lock the upper plate 215 in its current position.", "Consequently, the jig 219 is also prevented from further linear displacement thus preventing any further rotation about the rotation shaft 233 .", "[0041] In another embodiment of this invention, the jig 219 may be provided with a spherical member 229 positioned so that it comes into contact with the locking axle 227 when the locking driver 225 drives the locking axle 227 forward to lock the jig 219 in the optimum position.", "This spherical member 229 is to uniformly distribute a locking force upon the jig 219 when one end of the locking axle 227 comes into contact with it.", "In one embodiment of this invention and as shown in FIG. 5, two vertical pegs 240 extending vertically upwards in a y direction formed on the top surface of the top plate form the rotational limits that the jig 219 may rotate about the y axis.", "These pegs limit the rotation and act as stops for the jig 219 when the spherical member 229 come into contact with them.", "This assures that the spherical member 229 does not rotate outside the range where the locking axle 227 may come into contact with it when it is driven by the locking driver 225 .", "[0042] The alignment apparatus 200 for optical fiber blocks as described in the invention is mounted on the alignment driving actuator 290 that enables the jig 219 to pivot about a y rotational axis θy, so that the alignment apparatus does not require a separate driving motor for alignment in the y rotational axis θy, unlike the conventional alignment apparatus.", "[0043] The alignment driving actuator 290 requires three dimensional linear and rotational alignments in relation with a x-axis, a y-axis and a z-axis, respectively, where the linear alignments are performed along to the respective x-, y- and z-axes, i.e. in a left or right direction x, in an upward or downward direction y, and in a forward or backward direction z;", "whereas the rotational alignments are performed about the respective x-, y- and z-axes, i.e. about a x rotational axis Ox, about a y rotational axis θy, and about a z rotational axis θz.", "The linear alignments in all the x-, y- and z-axes and the rotational alignment about the z rotational axis are performed by a lower driving actuator 291 , and the rotational alignments to the x-axis is performed by an upper driving actuator 299 .", "[0044] To align the optical fiber block using the alignment apparatus 200 , the lower driving actuator 291 performs an approximate alignment first and then the upper driving actuator 299 performs a fine alignment.", "The alignment about the y rotational axis θy is automatically performed at the moment when the optical fiber block 201 contacts the counterpart component and the jig 219 rotates about the rotation shaft 233 .", "[0045] Opposingly, in the conventional alignment apparatus for optical fiber blocks 100 , the y axis of rotation θy is located on the rear side of the base plate 111 (see FIG. 1) and is spaced apart from the optical fiber block to a certain extent.", "Therefore, even a fine operation of the driving motor about the x rotational axis θx results in an increasing displacement of the optical fiber block because of the distance between the y axis of rotation θy and the optical fiber block.", "The conventional apparatus thus requires the driving motor to be operated with high precision.", "[0046] To the contrary, the alignment apparatus 200 for optical fiber blocks of this invention provides a y axis of rotation θy located through the position where the optical fiber block 201 is locked.", "This occurs due to the axis of the rotational shaft 233 that the jig 233 rotates about being located through the c enter of the optical fiber block 201 locked position.", "Therefore, it is easy to adjust a displacement of the optical fiber block 201 finely during the alignment of the optical fiber block.", "Moreover, it is possible to simultaneously perform the alignment about the y and x axes of rotation, θy and θx, because as a resilient force is applied in a direction in which the optical fiber block 201 contacts the counterpart component, the rotation shaft 233 and bearing 231 provide a rotational means for the jig.", "[0047] In the embodiments of the present invention as shown in FIG. 8, the following is a description of the procedure for aligning an optical fiber block using the alignment apparatus 200 for optical fiber blocks.", "The optical fiber block 201 is positioned on the alignment apparatus 200 , wherein the alignment apparatus 200 is mounted on the alignment driving actuator 290 .", "Here, the bracket 219 a is adjusted to accommodate the size of the optical fiber block 201 .", "When the optical fiber block 201 is positioned, the lower driving actuator 291 is operated to perform linear alignments initially for the x- and y-axial directions and the rotational alignment about the z rotational axis and then to advance the alignment apparatus 200 toward the counterpart component 202 , such as the planar wave-guide element, in the z-axial direction.", "[0048] When the alignment apparatus 200 advances coming into contact with the optical fiber block 201 , the lower driving actuator 291 causes the optical fiber block 201 to advance to a predetermined extent.", "As the optical fiber block 201 makes contact with the counterpart component, the resulting reaction force of the counterpart component 202 forces the jig 219 , upper plate 215 , and sliding table 217 in the opposite linear z direction relative to the displacement of the alignment apparatus 200 .", "It will be apparent that advancement of the alignment apparatus 200 by the lower driving actuator 291 should be limited to a displacement no greater than the maximum traveling range of the sliding table 217 on the lower plate 213 once the optical fiber block 201 makes contact with the counterpart component 202 .", "As the sliding table 217 , upper plate 215 , and jig 219 move in the opposite direction relative to the movement of the alignment apparatus 200 , a resilient force from the resilient means 221 acts upon the upper plate 215 and ultimately the jig 219 and the sliding table 217 as well.", "The reaction of the forces acting between the optical fiber block 201 and the counterpart component 202 causes the jig 219 to rotate about the y rotational axis θy.", "The jig 219 continues to rotate freely from the point when the optical fiber block 201 comes into contact with the counterpart component 202 until the point when the alignment is completed.", "[0049] After the alignment apparatus 200 is advanced to a proper position, the alignment about the x rotational axis θx is performed by the upper driving actuator 299 .", "At this point, the jig 219 also continues to rotate freely about the y rotational axis θy.", "This configuration efficiently provides for the precise and simultaneous alignment about both x and y axes rotational axes, θx and θy, without the need for an independent driving motor for alignment about the y axis of rotation.", "At such time when the optical fiber block 201 makes contact with the counterpart component, the displacement sensor 223 senses the position where the sliding table 217 is advanced to a maximum displacement.", ", At such time the alignment of the optical fiber block 201 is complete and the locking driver 225 causes the locking axle 227 to be advanced.", "In one embodiment of this invention the locking axle 227 advances and makes contact with the upper plate 215 preventing any further linear movement of the upper plate 215 , sliding table 217 , and jig 219 .", "This also restricts the jig 219 from any further rotation about rotational shaft 233 .", "In another embodiment the locking axle 227 advances towards the spherical member 229 provided with the jig 219 .", "Once contact is made the spherical member locks the jig 219 in place preventing it from further advancement or rotation and also preventing further advancement of the upper plate 215 and sliding table 217 .", "[0050] While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims." ]
RELATED APPLICATION This application is a continuation-in-part of application Ser. No. 243,886, filed Sept. 13, 1988 now U.S. Pat. No. 4,885,655, which is a continuation-in-part of application Ser. No. 106,048, filed Sept. 7, 1987, now U.S. Pat. No. 4,841,404. BACKGROUND OF THE INVENTION In numerous installations, a water pump and the electric motor which operates the pump are submerged within the body of water from which water is pumped. In some water pump installations, a water pump and an electric driving motor may be located a considerable distance from the electric control unit which supplies electrical energy to the electric motor. In each water pump installation, there is a possibility that the supply of water at the pump may cease or a coupling between the driving electric motor and the water pump may break, or for some other reason the electric motor operates without pumping operation of the water pump. If the supply of water to the water pump ceases, the pump may be severely damaged if it is operated. If the coupling between the electric motor breaks or for some other reason the pump is operated without pumping action, a signal should be provided in regard to such a condition, and/or the motor should be deenergized. However, numerous electric motors which operate water pumps have no protection against a condition in which the motor is operating while the pump is not pumping water. Therefore, such installations endanger the electric motor. Also, most installations which include means for protection of a water pump employ a motor control unit which is attached to support structure and also employ a pump protective unit which is separately attached to the support structure adjacent the motor control unit. The pump protective unit is electrically connected to the motor control unit. Thus, there are at least two units mounted upon support structure. Electric wires from a source of electrical energy are connected to the protective unit. Then electric wires are extended from the pump protective unit to the motor control unit, and the wires are connected to the pump protective unit and to the motor control unit. Then, electric wires are extended from the motor control unit to the electric motor, and the wires are connected to the motor control unit and to the electric motor. Therefore, a plurality of units are mounted upon support structure and numerous electric wires are attached to the units and extend to and from the units and to the electric motor. U.S. Patents which show protective electrical circuitry are U.S. Pat. Nos. 2,953,722, 3,417,290, 3,519,910, 3,600,657, 3,727,103, 3,931,559, 3,953,777, 4,034,269, 4,091,433, 4,117,408, 4,286,925, 4,290,007, 4,420,787, 4,642,478, 4,703,387. However, none of these patents shows structure in which a protective unit, as a module, is readily attachable to a motor control unit to form a combined assembly, without the mounting of an additional unit upon support structure, and without the necessity of additional conventional wiring. It is an object of this invention to provide means and a method by which an electric motor control unit which is mounted upon support structure can be readily and easily equipped with pump protection means without the necessity of mounting a separate motor protective unit upon the support structure and without the necessity of attaching conventional electric wires between the motor protective unit and the motor control unit. Another object of this invention is to provide a pump protective unit which constitutes a module which is readily attachable to an electric motor control unit. Another object of this invention is to provide a plug-in type electric motor protective unit which is adapted to plug-in to an electric motor control unit which is mounted upon support structure whereby the two units become a single assembly, without the necessity for conventional mounting and without the necessity of conventional electric wires between the units. Other objects and advantages of this invention reside in the construction of parts, the combination thereof, the method of construction and assembly and the mode of use, as will become more apparent from the following description. SUMMARY OF THE INVENTION This invention pertains to an electric motor and to a fluid pump which is operated by the electric motor. The invention comprises an adapter or module which provides pump protection and which can be readily inserted into an electric motor control unit. The adapter or module of this invention includes pump protective electrical circuitry and includes plug-in elements for insertion of the pump protective circuitry into the electric motor control unit. Thus, a single assembly is created which serves both as pump protective means and as motor control means. The single assembly is created easily and readily, and the single assembly is adapted to be mounted upon support structure, and without connection of conventional electric wires between the units of the assembly. BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS FIG. 1 is a diagrammatic view illustrating a prior art type of installation in which a pump protective unit and an electric motor control unit are separately mounted upon support structure, and the pump protective unit and the motor control unit are electrically wired together and connected to an electric motor which operates a fluid pump. FIG. 2 is a perspective view showing a prior art electric motor control unit which has power input conductors and motor connection conductors connected thereto and which controls starting and stopping operation of an electric motor which operates a pump. FIG. 3 is a perspective exploded view, drawn on substantially the same scale as FIG. 2, illustrating the manner by which two parts of the prior art motor control unit of FIG. 2 are attached together, electrically and mechanically. FIG. 4 is an exploded perspective view, drawn on substantially the same scale as FIGS. 2 and 3, showing a pump protective unit of this invention. This view also shows the motor control unit of FIGS. 2 and 3 and illustrates the manner by which the pump protective unit of this invention is connected electrically and mechanically to the motor control unit of FIGS. 2 and 3 to form a single assembly which comprises the motor control unit and the pump protective unit. FIG. 5 is a perspective view, drawn on substantially the same scale as FIGS. 2, 3, and 4, illustrating a step in attachment of the pump protective unit to the motor control unit to form a single assembly. FIG. 6 is a perspective view, drawn on substantially the same scale as FIGS. 2-5, showing the pump protective unit and the motor control unit attached together electrically and mechanically as a single assembly. FlG. 7 is a diagrammatic wiring and connection view illustrating the manner in which two parts of the prior art electric motor control unit of FIGS. 2, and 3 are attached together electrically. FIG. 8 is a diagrammatic wiring and connection views illustrating the manner in which a pump protective unit of this invention is electrically connected to the motor control unit of FIGS. 1, 2, and 3 to provide a single assembly. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates a prior art assembly in which a pump protective unit 12 is connected to an electric motor control unit 14. The electric motor control unit 14 and the protective unit 12 are two separate units which are separately mounted upon support structure. The electric motor control unit 14 may be any suitable unit for energization and deenergization of an electric motor, such as an electric motor 16 which is connected to a fluid pump 18 for operation of the pump 18. The pump protective unit 12 includes protective circuitry for protection of the pump 18 and the electric motor 16 against a situation in which the pump 18 is not pumping liquid. As illustrated in FIG. 1, power supply wires 20, shown herein as L 1 and L 2 , are connected to the protective unit 12. Electric wires 22 are connected to the protective unit 12 and to the motor control unit 14 and extend therebetween. Electric wires 24 are attached to the motor control unit 14 and to the electric motor 16 and extend therebetween. The protective unit 12 deenergizes the motor control unit 14 if the protective unit 12 senses that the motor 16 is operating while the pump 18 is not pumping fluid. Thus, the liquid pump 18 and the electric motor 16 are protected against a situation in which the pump 18 is not pumping liquid. The arrangement illustrated in FIG. 1 is suitable for protection of the electric motor 16 and the liquid pump 18. However, as shown, the units 12 and 14 are separately mounted upon support means, and several electric wires 22 and 24 are connected therebetween and to the motor 16. Thus, installation of the units 12 and 14 and connection thereof to the motor 16 is involved and time consuming. Furthermore, space upon support structure is required for mounting both the protective unit 12 and the motor control unit 14. For these reasons, inter alia, numerous electric motor and pump installations do not include pump motor protective means. For example, FIGS. 2 and 3 show a motor control unit 30, to which power supply lines 32 are connected and from which wires 34 extend to an electric motor 36 which operates a fluid pump 37. The unit 30 of FIGS. 2 and 3 includes no pump protection means. The motor control unit 30 of FIGS. 2, 3, and 7 includes a base 30b and a cover 30c. Within the base 30b is a connection block 38. The power supply lines 32 (L 1 and L 2 ) are connected to terminals 39 of the connection block 38, and the wires 34 are connected to terminals 41 of the connection block 38 and extend from the base 30b. FIG. 3 illustrates the manner in which the parts of 30b and 30c of the motor control unit 30 are connected together mechanically and electrically. FIG. 7 illustrates the manner in which the parts 30b and 30c of the motor control unit 30 are connected together electrically. Mounted within the cover 3Oc of the motor control unit 30 are motor starter and control elements 40. Joined to the motor starter and control elements 40 are wires 42 and 43 which extend from the starter and control elements 40. The wires 42 are attached to terminals 45 of a connection block 44, and the wires 43 are connected to terminals 47 of the connection block 44. The connection block 44 includes protuberant blades 46 which are electrically and physically connected to the terminals 45. The connection block 44 includes blades 48 which are electrically and physically connected to the terminals 47. The blades 46 and 48 and the connection block 44 of the cover 30c are adapted to enter slotted openings or receptacles 50 and 52, respectively in the connection block 38 in the base 30b, as illustrated in FIGS. 3 and 7. In attaching the cover 30c to the base 30b of the prior art unit 30, the blades 46 of the connection block 44 are inserted into the slotted receptacles 50, and the blades 48 are inserted into the slotted receptacles 52 of the connection block 38 of the base 30b. As this electrical connection process occurs, the cover 30c is placed into engagement with the base 30b. Thus, the motor starter and control elements 40, which are electrically connected to the connection block 44, become electrically connected to the connection block 38 and to the wires 32 and 34 when the cover 30c is placed into engagement with the base 30b to enclose the base 30b. These electrical connections are illustrated diagrammatically in FIG. 7. For physical securing of the cover 30c to the base 30b a screw 54 attaches the cover 30c to the base 30b. When the base 30b is closed by the cover 30c, the motor control unit 30 has the appearance shown in FIG. 2, and there is no provision. For protection of the pump 37. This invention provides means by which a motor control unit, such as the motor control unit 30, is quickly and easily equipped with pump protection means. FIG5. 4 and 5 show a pump protective unit 60 of this invention. The pump protective unit 60 is shown as comprising a housing member 60A and a housing member 60B which are attached together in back-to-back relationship. However, the housing members 60A and 60B may comprise a single housing. The housing member 60A encloses pump protective circuitry 64 which is connected by electrical conductors 67, shown in FIG. 8, to protuberant blades 68 which are mounted upon a connection block 70, shown in FIGS. 4 and 8. Preferably, the pump protective unit 60 includes protective circuitry such as that disclosed in U.S. Pat. No. 4,420,787. The connection block 70 also has blades 74 to which are connected wires 76, shown in FIG. 8. The protective unit 60 also has a connection block 80, shown in FIGS. 5 and 8. The wires 76 are also connected to terminals 78 of the connection block 80. The terminals 78 are electrically and mechanically connected to slotted receptacles 84 in the terminal block 80. The pump protective circuitry and elements 64 are also connected by wires 87, shown in FIG. 8, to terminals 88 on the connection block 80. The terminals 88 are connected electrically and mechanically to slotted receptacles 90 in the connection block 80. The blades 68 of the connection block 70 of the protective unit 60 are adapted to be inserted into the slotted receptacles 52 in the connection block 38 of the base 30b. The blades 74 of the connection block 70 of the protective unit 60 are adapted to be inserted into the slotted receptacles 50 of the base 30b. The blades 46 and 48 of the connection block 44 of the cover 30c are adapted to be inserted into the slotted receptacles 84 and 90, respectively, of the connection block 80 of the protective unit 60. The blades 74 and 68 of the connection block 70 of the protective unit 60 are adapted to be inserted into the slotted receptacles 50 and 52, respectively of the connection block 38 of the base 30b. Thus, the protective unit 60 becomes a part of the motor control unit 30, and the combined units 60 and 30 have the appearance shown in FIG. 6 and function together as a single assembly, as illustrated in FIG. 4, 5, 6, and 8. As illustrated in FIG. 4, the screw 54 attaches the cover 30c of the motor control unit 30 to the protective unit 60, and a screw 92 attaches the protective unit 60 to the base 30b of the motor control unit 30. Thus, the protective unit 60 readily becomes a part of the motor control unit 30, without the necessity of additional mounting upon support structure and without the necessity of attaching additional wires in a conventional manner. Although the preferred embodiment of the electric motor control and protective assembly of this invention has been described, it will be understood that within the purview of this invention various changes may be made in the form, details, proportion and arrangement of elements, the combination thereof, and the mode and method of operation, which generally stated consist in an electric motor control and protective assembly and method of this invention within the scope of the appended claims.
A combination electric motor control and pump protective assembly in which a protective unit is readily inserted as a module into an existing motor control unit. The units which form the single combined assembly are electrically attached together by blade and socket members to which electrical devices are connected. Thus, a pump protective unit can be quickly and readily added to an existing motor control unit which is mounted upon support structure. Therefore, a motor control unit and a pump protective unit is quickly formed into a combined assembly upon existing support structure, without the mounting of an additional member upon support structure and without additional wiring.
Briefly summarize the invention's components and working principles as described in the document.
[ "RELATED APPLICATION This application is a continuation-in-part of application Ser.", "No. 243,886, filed Sept.", "13, 1988 now U.S. Pat. No. 4,885,655, which is a continuation-in-part of application Ser.", "No. 106,048, filed Sept.", "7, 1987, now U.S. Pat. No. 4,841,404.", "BACKGROUND OF THE INVENTION In numerous installations, a water pump and the electric motor which operates the pump are submerged within the body of water from which water is pumped.", "In some water pump installations, a water pump and an electric driving motor may be located a considerable distance from the electric control unit which supplies electrical energy to the electric motor.", "In each water pump installation, there is a possibility that the supply of water at the pump may cease or a coupling between the driving electric motor and the water pump may break, or for some other reason the electric motor operates without pumping operation of the water pump.", "If the supply of water to the water pump ceases, the pump may be severely damaged if it is operated.", "If the coupling between the electric motor breaks or for some other reason the pump is operated without pumping action, a signal should be provided in regard to such a condition, and/or the motor should be deenergized.", "However, numerous electric motors which operate water pumps have no protection against a condition in which the motor is operating while the pump is not pumping water.", "Therefore, such installations endanger the electric motor.", "Also, most installations which include means for protection of a water pump employ a motor control unit which is attached to support structure and also employ a pump protective unit which is separately attached to the support structure adjacent the motor control unit.", "The pump protective unit is electrically connected to the motor control unit.", "Thus, there are at least two units mounted upon support structure.", "Electric wires from a source of electrical energy are connected to the protective unit.", "Then electric wires are extended from the pump protective unit to the motor control unit, and the wires are connected to the pump protective unit and to the motor control unit.", "Then, electric wires are extended from the motor control unit to the electric motor, and the wires are connected to the motor control unit and to the electric motor.", "Therefore, a plurality of units are mounted upon support structure and numerous electric wires are attached to the units and extend to and from the units and to the electric motor.", "U.S. Patents which show protective electrical circuitry are U.S. Pat. Nos. 2,953,722, 3,417,290, 3,519,910, 3,600,657, 3,727,103, 3,931,559, 3,953,777, 4,034,269, 4,091,433, 4,117,408, 4,286,925, 4,290,007, 4,420,787, 4,642,478, 4,703,387.", "However, none of these patents shows structure in which a protective unit, as a module, is readily attachable to a motor control unit to form a combined assembly, without the mounting of an additional unit upon support structure, and without the necessity of additional conventional wiring.", "It is an object of this invention to provide means and a method by which an electric motor control unit which is mounted upon support structure can be readily and easily equipped with pump protection means without the necessity of mounting a separate motor protective unit upon the support structure and without the necessity of attaching conventional electric wires between the motor protective unit and the motor control unit.", "Another object of this invention is to provide a pump protective unit which constitutes a module which is readily attachable to an electric motor control unit.", "Another object of this invention is to provide a plug-in type electric motor protective unit which is adapted to plug-in to an electric motor control unit which is mounted upon support structure whereby the two units become a single assembly, without the necessity for conventional mounting and without the necessity of conventional electric wires between the units.", "Other objects and advantages of this invention reside in the construction of parts, the combination thereof, the method of construction and assembly and the mode of use, as will become more apparent from the following description.", "SUMMARY OF THE INVENTION This invention pertains to an electric motor and to a fluid pump which is operated by the electric motor.", "The invention comprises an adapter or module which provides pump protection and which can be readily inserted into an electric motor control unit.", "The adapter or module of this invention includes pump protective electrical circuitry and includes plug-in elements for insertion of the pump protective circuitry into the electric motor control unit.", "Thus, a single assembly is created which serves both as pump protective means and as motor control means.", "The single assembly is created easily and readily, and the single assembly is adapted to be mounted upon support structure, and without connection of conventional electric wires between the units of the assembly.", "BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS FIG. 1 is a diagrammatic view illustrating a prior art type of installation in which a pump protective unit and an electric motor control unit are separately mounted upon support structure, and the pump protective unit and the motor control unit are electrically wired together and connected to an electric motor which operates a fluid pump.", "FIG. 2 is a perspective view showing a prior art electric motor control unit which has power input conductors and motor connection conductors connected thereto and which controls starting and stopping operation of an electric motor which operates a pump.", "FIG. 3 is a perspective exploded view, drawn on substantially the same scale as FIG. 2, illustrating the manner by which two parts of the prior art motor control unit of FIG. 2 are attached together, electrically and mechanically.", "FIG. 4 is an exploded perspective view, drawn on substantially the same scale as FIGS. 2 and 3, showing a pump protective unit of this invention.", "This view also shows the motor control unit of FIGS. 2 and 3 and illustrates the manner by which the pump protective unit of this invention is connected electrically and mechanically to the motor control unit of FIGS. 2 and 3 to form a single assembly which comprises the motor control unit and the pump protective unit.", "FIG. 5 is a perspective view, drawn on substantially the same scale as FIGS. 2, 3, and 4, illustrating a step in attachment of the pump protective unit to the motor control unit to form a single assembly.", "FIG. 6 is a perspective view, drawn on substantially the same scale as FIGS. 2-5, showing the pump protective unit and the motor control unit attached together electrically and mechanically as a single assembly.", "FlG.", "7 is a diagrammatic wiring and connection view illustrating the manner in which two parts of the prior art electric motor control unit of FIGS. 2, and 3 are attached together electrically.", "FIG. 8 is a diagrammatic wiring and connection views illustrating the manner in which a pump protective unit of this invention is electrically connected to the motor control unit of FIGS. 1, 2, and 3 to provide a single assembly.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates a prior art assembly in which a pump protective unit 12 is connected to an electric motor control unit 14.", "The electric motor control unit 14 and the protective unit 12 are two separate units which are separately mounted upon support structure.", "The electric motor control unit 14 may be any suitable unit for energization and deenergization of an electric motor, such as an electric motor 16 which is connected to a fluid pump 18 for operation of the pump 18.", "The pump protective unit 12 includes protective circuitry for protection of the pump 18 and the electric motor 16 against a situation in which the pump 18 is not pumping liquid.", "As illustrated in FIG. 1, power supply wires 20, shown herein as L 1 and L 2 , are connected to the protective unit 12.", "Electric wires 22 are connected to the protective unit 12 and to the motor control unit 14 and extend therebetween.", "Electric wires 24 are attached to the motor control unit 14 and to the electric motor 16 and extend therebetween.", "The protective unit 12 deenergizes the motor control unit 14 if the protective unit 12 senses that the motor 16 is operating while the pump 18 is not pumping fluid.", "Thus, the liquid pump 18 and the electric motor 16 are protected against a situation in which the pump 18 is not pumping liquid.", "The arrangement illustrated in FIG. 1 is suitable for protection of the electric motor 16 and the liquid pump 18.", "However, as shown, the units 12 and 14 are separately mounted upon support means, and several electric wires 22 and 24 are connected therebetween and to the motor 16.", "Thus, installation of the units 12 and 14 and connection thereof to the motor 16 is involved and time consuming.", "Furthermore, space upon support structure is required for mounting both the protective unit 12 and the motor control unit 14.", "For these reasons, inter alia, numerous electric motor and pump installations do not include pump motor protective means.", "For example, FIGS. 2 and 3 show a motor control unit 30, to which power supply lines 32 are connected and from which wires 34 extend to an electric motor 36 which operates a fluid pump 37.", "The unit 30 of FIGS. 2 and 3 includes no pump protection means.", "The motor control unit 30 of FIGS. 2, 3, and 7 includes a base 30b and a cover 30c.", "Within the base 30b is a connection block 38.", "The power supply lines 32 (L 1 and L 2 ) are connected to terminals 39 of the connection block 38, and the wires 34 are connected to terminals 41 of the connection block 38 and extend from the base 30b.", "FIG. 3 illustrates the manner in which the parts of 30b and 30c of the motor control unit 30 are connected together mechanically and electrically.", "FIG. 7 illustrates the manner in which the parts 30b and 30c of the motor control unit 30 are connected together electrically.", "Mounted within the cover 3Oc of the motor control unit 30 are motor starter and control elements 40.", "Joined to the motor starter and control elements 40 are wires 42 and 43 which extend from the starter and control elements 40.", "The wires 42 are attached to terminals 45 of a connection block 44, and the wires 43 are connected to terminals 47 of the connection block 44.", "The connection block 44 includes protuberant blades 46 which are electrically and physically connected to the terminals 45.", "The connection block 44 includes blades 48 which are electrically and physically connected to the terminals 47.", "The blades 46 and 48 and the connection block 44 of the cover 30c are adapted to enter slotted openings or receptacles 50 and 52, respectively in the connection block 38 in the base 30b, as illustrated in FIGS. 3 and 7.", "In attaching the cover 30c to the base 30b of the prior art unit 30, the blades 46 of the connection block 44 are inserted into the slotted receptacles 50, and the blades 48 are inserted into the slotted receptacles 52 of the connection block 38 of the base 30b.", "As this electrical connection process occurs, the cover 30c is placed into engagement with the base 30b.", "Thus, the motor starter and control elements 40, which are electrically connected to the connection block 44, become electrically connected to the connection block 38 and to the wires 32 and 34 when the cover 30c is placed into engagement with the base 30b to enclose the base 30b.", "These electrical connections are illustrated diagrammatically in FIG. 7. For physical securing of the cover 30c to the base 30b a screw 54 attaches the cover 30c to the base 30b.", "When the base 30b is closed by the cover 30c, the motor control unit 30 has the appearance shown in FIG. 2, and there is no provision.", "For protection of the pump 37.", "This invention provides means by which a motor control unit, such as the motor control unit 30, is quickly and easily equipped with pump protection means.", "FIG5.", "4 and 5 show a pump protective unit 60 of this invention.", "The pump protective unit 60 is shown as comprising a housing member 60A and a housing member 60B which are attached together in back-to-back relationship.", "However, the housing members 60A and 60B may comprise a single housing.", "The housing member 60A encloses pump protective circuitry 64 which is connected by electrical conductors 67, shown in FIG. 8, to protuberant blades 68 which are mounted upon a connection block 70, shown in FIGS. 4 and 8.", "Preferably, the pump protective unit 60 includes protective circuitry such as that disclosed in U.S. Pat. No. 4,420,787.", "The connection block 70 also has blades 74 to which are connected wires 76, shown in FIG. 8. The protective unit 60 also has a connection block 80, shown in FIGS. 5 and 8.", "The wires 76 are also connected to terminals 78 of the connection block 80.", "The terminals 78 are electrically and mechanically connected to slotted receptacles 84 in the terminal block 80.", "The pump protective circuitry and elements 64 are also connected by wires 87, shown in FIG. 8, to terminals 88 on the connection block 80.", "The terminals 88 are connected electrically and mechanically to slotted receptacles 90 in the connection block 80.", "The blades 68 of the connection block 70 of the protective unit 60 are adapted to be inserted into the slotted receptacles 52 in the connection block 38 of the base 30b.", "The blades 74 of the connection block 70 of the protective unit 60 are adapted to be inserted into the slotted receptacles 50 of the base 30b.", "The blades 46 and 48 of the connection block 44 of the cover 30c are adapted to be inserted into the slotted receptacles 84 and 90, respectively, of the connection block 80 of the protective unit 60.", "The blades 74 and 68 of the connection block 70 of the protective unit 60 are adapted to be inserted into the slotted receptacles 50 and 52, respectively of the connection block 38 of the base 30b.", "Thus, the protective unit 60 becomes a part of the motor control unit 30, and the combined units 60 and 30 have the appearance shown in FIG. 6 and function together as a single assembly, as illustrated in FIG. 4, 5, 6, and 8.", "As illustrated in FIG. 4, the screw 54 attaches the cover 30c of the motor control unit 30 to the protective unit 60, and a screw 92 attaches the protective unit 60 to the base 30b of the motor control unit 30.", "Thus, the protective unit 60 readily becomes a part of the motor control unit 30, without the necessity of additional mounting upon support structure and without the necessity of attaching additional wires in a conventional manner.", "Although the preferred embodiment of the electric motor control and protective assembly of this invention has been described, it will be understood that within the purview of this invention various changes may be made in the form, details, proportion and arrangement of elements, the combination thereof, and the mode and method of operation, which generally stated consist in an electric motor control and protective assembly and method of this invention within the scope of the appended claims." ]
BACKGROUND OF THE INVENTION [0001] The present invention relates to an electric-control-type throttle apparatus for controlling the amount of intake air, used in an internal combustion engine. [0002] Japanese Patent Publication 177534/1996 discloses a throttle valve control apparatus including a throttle body, a throttle valve installed in the air intake path of the throttle body via a rotatable shaft, an actuator for driving the throttle valve via a plurality of gears, and a detection means for detecting the rotation angle of the throttle valve. [0003] The plurality of gears of this apparatus is composed of the first gear fixed to the shaft of the throttle valve, the third gear fixed to the rotation shaft of the motor used as the actuator, and the second gear between the first and third gears. This composition can increase the speed reducing ratio, which can finely control the opening of the throttle valve. [0004] Although the opening of the throttle valve can be finely controlled by obtaining a large gear ratio in the above-mentioned conventional throttle apparatus, it is not stated how to determine the characteristics of the motor, or the gear ratio with which the torque of the motor is transmitted to the throttle valve in order to realize the desired operation speed of the throttle valve. [0005] In the above conventional apparatus, the throttle valve is opened or closed by the motor. If the opening or closing of the throttle valve does not respond quickly to the motion of the acceleration pedal operated by a driver, the driver notices the gap between the operations performed by the driver itself and changes in the operational state of the internal engine. However, in the electric-control-type throttle apparatus, it is necessary to provide a force applying means for quickly returning the position of the throttle valve to the predetermined opening in the event of a problem with the fail-safe operation. Therefore, the operation speed of the throttle valve cannot easily be increased, and it is important to adequately determine the force from the force applying means, the performance of the motor, and the speed reducing ratio of the rotation speed of the motor to that of the throttle valve. [0006] If this conventional throttle apparatus is applied to a direct injection engine in which fuel is directly injected in each cylinder, the following problems will occur. [0007] In a conventionally used port injection engine in which fuel is injected into an air intake pipe, the engine is operated near the theoretical air to fuel ratio of 14.7. On the other hand, a direct injection engine is operated in a wide range of an air to fuel ratio of 14.7 (theoretical ratio) to more than 40 (superlean ratio). Fuel burning near the theoretical air to fuel ratio is called the uniform mixture charge burning state, and fuel burning at an air to fuel ratio higher than the theoretical ratio is called the stratified charge burning state. It is easy to realize the stratified charge burning state in a direct injection engine because fuel is directly injected into a cylinder. FIG. 12 is a diagram showing the relationship between the fuel burning modes and operation states of an engine. The stratified charge burning mode is performed below an engine rotation speed of approximately 3000 rpm. [0008] In implementing those burning modes, it is necessary to open the throttle valve wider in the stratified charge burning state than in the uniform mixture charge burning state. Therefore, when the operation of the engine is changed from the stratified charge burning state to the uniform mixture charge burning, the throttle valve is driven in the valve closing direction. FIG. 4A and FIG. 4B show changes in time of the actuating amount of an acceleration pedal and changes in time of the opening of the throttle valve corresponding to the changes of the actuating amount of the acceleration pedal, respectively. [0009] As shown in FIG. 4B, the throttle valve is widely opened in the stratified charge burning state, and it is driven once in the valve closing direction when the operation of the engine is switched to the uniform mixture charge burning state. If the time necessary for the switching operation is long, the switching operation between the two burning states cannot be smoothly carried out, and the output power of the engine rapidly changes. Consequently, a shock caused by the switching operation is transmitted to the passengers and the driver of the vehicle, which degrades both the operationality of the vehicle and the comfort of riding in the vehicle. [0010] On the other hand, if the throttle valve is driven at a high speed, it is also necessary to rotate the motor driving the throttle valve at a high speed. In these high speed operations, the higher speed the motor is rotated at, the larger the counter-electromotive force for braking the rotation of the throttle valve becomes. Therefore, there may be a large current that is beyond the permitted value for the switching elements used in a drive circuit for driving the motor. It is then necessary to use switching elements with the higher permitted current value for the drive circuit of the motor. However, switching elements with the required larger permitted current cannot be always acquired. Even though switching elements with the required larger permitted current can be acquired, such elements are very expensive and unsuitable for use in a vehicle. For another means for restricting the value of the current flowing in the drive circuit of the motor below the permitted current value, it is also possible to provide a current limiting circuit in the drive circuit. However, this means increases the production cost, and if the provided current limiting circuit breaks down, it is possible that the increased current cannot be kept below the permitted current value. Thus, this means does not offer a sufficient fail-safe function. SUMMARY OF THE INVENTION [0011] An objective of the present invention is to realize a highly reliable electric-control-type throttle apparatus capable of performing the usual opening and closing operations and offering a fail-safe function of securing the position of a throttle valve at which a vehicle can be safely driven at an appropriate operation speed even in the event of a failure of the motor for driving the throttle valve. [0012] The first feature of the present invention designed to attain the above objective is to provide an electric-control-type throttle apparatus including a motor, a speed reducing mechanism for reducing the rotation speed that is transmitted from the rotation speed of the motor, a throttle valve connected to the speed reducing mechanism, and a force applying means for applying force to the throttle valve towards returning the valve to its initial position, for adjusting the opening of the throttle valve by driving the motor; wherein the specification parameters of the motor, the speed reducing mechanism, and the force applying means have their values such that the operation time t from the minimum opening to the maximum opening of the throttle valve, which is determined by the following equation (1): t = π ( T max  N - T s ) J , ( 1 ) [0013] where T max =K m E/R m and T s : the preload of a return spring of the force applying means [Nm], T max : the torque of the motor [Nm], N: the speed reducing ratio, J: the equivalent moment of inertia [kgm 2 ], K m the torque constant [Nm/A], R m : the impedance of the motor [Ω], and E: the voltage applied to the motor [V], [0014] is shorter than a prescribed target operation time t★. [0015] The second feature of the present invention is that, in the above electric-control-type throttle apparatus of the first feature, the target operation time t★ is 80 ms. [0016] The third feature of the present invention is that, in the above electric-control-type throttle apparatus of the second feature, the values of the specification parameters are those at the temperature of 120° C. [0017] The fourth feature of the present invention is that, in the above electric-control-type throttle apparatus of the second feature, the applied voltage is approximately 13 V. [0018] The fifth feature of the present invention is that, in the above electric-control-type throttle apparatus of the second feature, the torque constant K m is 0.035±0.0035 Nm/A, the resistance of the motor R m is 1.6±0.1 Ω, and the speed reducing ratio N is from 9.8 to 10.8, preferably 10.3 at the temperature 20° C. [0019] The sixth feature of the present invention is that, in the above electric-control-type throttle apparatus of the fifth feature, the preload torque T s of the return spring is from 0.3 to 0.4 Nm, preferably 0.35 Nm. [0020] The seventh feature of the present invention is that, in the above electric-control-type throttle apparatus of the second feature, the torque constant K m is from 0.025 to 0.04 Nm/A, preferably from 0.03 to 0.037 Nm/A, and the resistance of the motor R m . is from 1.0 to 2.5 Ω, preferably from 1.3 to 2.2 Ω. [0021] The eighth feature of the present invention is that, in the above electric-control-type throttle apparatus of the first feature, the specification parameters have values such that a differential coefficient of the operation time t expressed by the equation (1) with respect to the speed reducing ratio N is positive. [0022] The ninth feature of the present invention is that, in the above electric-control-type throttle apparatus of the eighth feature, the speed reducing ratio N is from 9.8 to 10.8. [0023] The tenth feature of the present invention is that the above electric-control-type throttle apparatus of the first feature further includes a detector for detecting the applied voltage E, a means for measuring the counter-electromotive force induced in the motor, and a control unit for controlling the motor, wherein the control unit predicts changes in the value obtained by dividing the sum of the detected applied voltage E and the measured counter-electromotive force by the impedance R m of the motor, and controls the applied voltage so as not to flow current beyond the permitted current value in the circuit used for driving the motor. [0024] The eleventh feature of the present invention is to provide an electric-control-type throttle apparatus including a motor, a speed reducing mechanism for reducing the rotation speed that is transmitted from the rotation speed of the motor, a throttle valve connected to the speed reducing mechanism, and a force applying means for applying force to the throttle valve towards returning the valve to its initial position, and adjusting the opening of the throttle valve by driving the motor; wherein the specification parameters of the motor, and the force applying means have their values satisfying the following inequality (2): R m > ( E + K e  θ . m ) I lim , ( 2 ) [0025] where θ m =ι v ·N, and V m =K e θ m , and R m is the resistance of the motor [Ω], E: the voltage applied to the motor [V], K e : the induction voltage coefficient [V/rpm], θ m : the rotation speed of the motor [rpm], θ v : the rotation speed of the throttle valve [rpm], N: the speed reducing ratio, and V m : the counter-electromotive force induced in the motor. [0026] The twelfth feature of the present invention is that, in the above electric-control-type throttle apparatus of the eleventh feature, the applied voltage E is approximately 13 V, and the motor impedance R m is more than 1.2 Ω at 20° C. [0027] The thirteenth feature of the present invention is that the above electric-control-type throttle apparatus of the eleventh feature further includes a detector for detecting the applied voltage E and a control unit for controlling the motor, wherein the control unit predicts changes in the value of the right-hand side of the inequality (2) and controls the applied voltage E so as to always satisfy the inequality (2). [0028] The fourteenth feature of the present invention is that, in the above electric-control-type throttle apparatus of the first to thirteenth features, the throttle apparatus is used in a direct-injection combustion engine. BRIEF DESCRIPTION OF THE DRAWINGS [0029] [0029]FIG. 1 is a horizontal section of an electric-control-type throttle apparatus of an embodiment according to the present invention. [0030] [0030]FIG. 2 is an illustration showing the principle of a default mechanism. [0031] [0031]FIG. 3 is an illustration for showing the force applied to the shaft of a throttle valve by a return spring and a default spring. [0032] [0032]FIGS. 4A and 4B show operations of a throttle valve in an electric-control-type throttle apparatus, corresponding to changes in time of the actuating amount of an acceleration pedal. [0033] [0033]FIGS. 5A and 5B show the relationship between the operation time t, and the speed reducing ratio and temperature, respectively. [0034] [0034]FIG. 6 is a schematic diagram showing the composition of a direct-injection engine using an electric-control-type throttle apparatus. [0035] [0035]FIG. 7 is a diagram showing changes of the output power of a direct-injection engine when the fuel burning mode is switched. [0036] [0036]FIG. 8 is a front view of the electric-control-type throttle valve shown in FIG. 1, which is viewed from the direction of the shaft of the throttle valve. [0037] [0037]FIGS. 9A and 9B show a drive circuit for driving the motor and voltage pulse patterns applied to the drive circuit, respectively. [0038] [0038]FIG. 10 is a conceptual diagram showing a current flow path when voltage is applied to the motor to cause the torque in a direction inverse to that of the present rotation of the motor. [0039] [0039]FIG. 11 is a diagram for explaining the motion of the electric-control-type throttle apparatus. [0040] [0040]FIG. 12 is a diagram showing the relationship between the fuel burning modes and operation states of an engine. [0041] [0041]FIG. 13 shows a delay in the response of the intake air flow rate to a step change of the opening of a throttle valve. [0042] [0042]FIG. 14 shows the induced counter-electromotive force and the current flowing in the motor used in the electric-control-type throttle apparatus. [0043] [0043]FIG. 15 shows the relationship between the limit values of the motor resistance and the values of the torque constant under the condition of each value of the operation time of 80 ms, the necessary sticking release torque of 110 kgfmm, and the permitted current of 20 A, in which the equivalent moment J of inertia is set 0.0013 kgm 2 . DETAILED DESCRIPTION OF THE EMBODIMENTS [0044] Hereinafter, details of embodiments will be explained with reference to the drawings. [0045] [0045]FIG. 1 shows a horizontal section of an electric-control-type throttle apparatus of an embodiment according to the present invention, and FIG. 8 is a front view of a gear part in the electric-control-type throttle valve shown in FIG. 1, which is viewed from the direction of the shaft of the throttle valve. [0046] The electric-control-type throttle apparatus comprises a throttle body 101 including an air intake path and a motor 107 generating the torque, a motor shaft 105 of the motor 107 , a motor gear 106 fixed on the motor shaft 105 , a large intermediate gear 104 a engaged with the motor gear 106 , a small intermediate gear 104 b fixed on the motor shaft 105 coaxially with the large intermediate gear 104 a, a valve gear 103 engaged with the small intermediate gear 104 b, a valve shaft 108 on which the valve gear 103 is fixed, a throttle valve 102 screwed to the valve shaft 108 , and a default mechanism using a return spring 111 and a default spring 112 . [0047] Specification parameters determining the performance of the electric-control-type throttle apparatus are indicated as follows. The specification parameters concerning the motor 107 are the torque constant, the counter-electromotive (induction) voltage constant, the motor inductance, the motor resistances, the voltage applied to the motor 107 , etc. Moreover, the specification parameters concerning the mechanical composition are the moment of inertia, the speed reducing ratio (gear ratio), the preload torque of the return spring 111 , and so on. [0048] Furthermore, a throttle position sensor 110 for detecting the position of the throttle valve 102 is provided between the default mechanism and the throttle valve 102 . [0049] In order to reduce the rotation speed that is transmitted from the rotation speed of the motor 107 to the valve shaft 108 , it is necessary to make the pitch circle diameter of the motor gear 106 smaller than that of the large intermediate gear 104 engaged with the motor gear 106 . Also, it is necessary to make the pitch circle diameter of the small intermediate gear 104 b smaller than that of the valve gear 103 engaged with the small intermediate gear 104 b. Because the rotation angle of the throttle valve 102 is at most 90 degrees, it is sufficient that the valve gear 103 rotates for 90 degrees. Thus, the valve gear is formed as a fan shape. [0050] The large and small intermediate gears 104 a and 104 b are formed by shaping the respective tooth spaces in the same member. A hole is made in the center of the intermediate gears 104 a and 104 b, and an intermediate gear shaft 109 is press-fitted through the hole in the throttle body 101 . Moreover, in order to reduce the friction and backlashes in the intermediate gears 104 a and 104 b, a dry bearing is inserted between the intermediate gears 104 a and 104 b, and the intermediate gear shaft 109 . [0051] A flange is provided at the motor 107 vertically to the motor shaft 105 , and is fixed to the throttle body 101 with two screws. In this embodiment, the large intermediate gear 104 a is arranged in a position near the throttle body 101 on the intermediate gear shaft 109 so that the length of the motor shaft 105 is made as short as possible. By this arrangement, it is possible to use the motor shaft 105 of a small diameter because of the increased stiffness with the motor shaft 105 . Consequently, the moment of inertia can be decreased, which improves the response of the throttle apparatus. [0052] [0052]FIG. 2 is a illustration showing the principle of the default mechanism. In this figure, for simplicity of explanation, the principle is illustrated by imaging that the rotational motion of a lever 204 , the return spring 201 ( 111 ), and the default spring 202 ( 112 ) is converted to the linear motion. The lever 204 is connected to the valve shaft 108 , and is driven by the motor 107 . When the lever 204 is moved left, the throttle valve 102 is driven in the valve opening direction. The default mechanism maintains the throttle valve 102 at the predetermined position (called the default position) by using a pair of springs. The default position is set as the position of the throttle valve, such that the vehicle can start without over-speeding. The return spring 201 ( 111 ) is attached to a member 203 and the lever 204 is connected to the throttle shaft 108 . The default spring 202 ( 112 ) is attached to the member 203 and a body 205 . [0053] If the motor 107 stops, the lever 204 is pushed to the member 203 by the return spring 201 , and the member 203 is maintained at the default position by the default spring 202 . In the open-position range beyond the default position of the lever 204 , the member 203 touches the body 205 and stops there, and the force is applied to the lever 204 by the return spring 201 in the valve closing direction. On the other hand, in the closed-position range below the default position of the lever 204 , the force of the default spring 202 is applied to the throttle valve 102 via the lever 204 and the member 203 . [0054] [0054]FIG. 3 is an illustration for showing the torque applied to the valve shaft 108 of the throttle valve 102 by the default mechanism using the return spring 111 and the default spring 112 . The preload is applied to both the return spring 111 and the default spring 112 in advance. The optimal value therefore exists for each preload. If the preload is too large, it causes a long response time in the opening and closing operations of the throttle valve 102 , and if the preload is too small, the throttle valve 102 cannot return to the default position, which is due to air resistance and friction in the rotation. The preload of the return spring 111 is important for reliably returning the throttle valve 102 to the default position, and the force of 30-40 kgfmm is necessary for the preload. [0055] In the following, the operations of the electric-control-type throttle valve will be explained. [0056] When torque larger than the spring force of the default mechanism is applied to the valve shaft 108 by the motor 107 , the motor shaft 105 rotates, and the motor gear 106 and the large intermediate gear 104 a also rotate according to the rotation of the motor shaft 105 . Because the number of teeth on the motor gear 106 is less than that on the large intermediate gear 104 a, the rotation speed of the motor 107 is reduced. The small intermediate gear 104 b rotates together with the large intermediate gear 104 a, and transmits the torque to the valve gear 103 . Moreover, because the pitch circle diameter of the small intermediate gear 104 b is set smaller than that of the valve gear 103 , the rotation speed is further reduced. Thus, the rotation speed of the motor 107 is reduced by two steps, and is transmitted to the valve shaft 108 . [0057] [0057]FIG. 6 shows an example of the composition of a direct-injection engine using the electric-control-type throttle apparatus of the present invention. The electric-control-type throttle apparatus 61 is arranged at the upper stream side of a direct-injection engine 62 , in an air intake tube 67 . A control unit 63 for sending control signals to the motor 107 and driving the motor 107 is connected to the electric-control-type throttle apparatus 61 via a throttle harness 66 . [0058] The control unit 63 receives information from the engine 62 via an engine harness 64 , and from other parts of the vehicle via a harness 65 , and determines the target position of the throttle valve 102 . Moreover, the control unit 63 receives a position signal detected by the throttle position sensor 110 for detecting the position of the throttle valve 102 , and controls the position of the throttle valve 102 so as to follow the determined target position. [0059] A drive circuit 68 for adjusting the power fed to the motor 107 is incorporated in the control unit 63 ,. The drive circuit 8 uses the PWM method for controlling the torque generated by the motor 107 by feeding voltage pulses of the variable width to the motor 107 . Transistors or FETs (Field Effect Transistor) are used as switching elements to generate the voltage pulses, and the permitted current is assigned to those transistors. If a current larger than the permitted current flows in those switching elements of the transistors or FETs, the transistors possibly break down. [0060] In Table 1, specification parameters of the motor 107 and the gear ratio of the speed reducing mechanism in this embodiment are shown. By using the specification parameters shown in Table 1, it is possible to ensure that the response time of the electronic throttle apparatus is reduced and the overcurrent flowing in the drive circuit is also prevented. TABLE 1 20° C. 120° C. −30° C. Torque constant kgfmm/A 3.54 3.07 3.76 Nm/A 0.0347 0.0301 0.0368 Counter- V/krpm 3.65 3.18 3.92 electromotive force Motor impedance Ω 1.61 2.24 1.29 Preload of kgfmm 36 36 36 return spring Nm 0.353 0.353 0.353 Speed-reducing ratio — 10.27 10.27 10.27 [0061] These specification parameters are explained below. [0062] When the voltage is applied to a motor 107 , and the motor 107 begins to rotate, the motor 107 generates the induced voltage in the direction opposite that of the applied voltage, which is due to the power generating function which the motor 107 possesses. This induced voltage is called the counter-electromotive force, and is proportional to the rotation speed of the motor. Because the motor 107 used in the electric-control-type throttle apparatus is controlled so that the position of the throttle valve follows the target position, when the position approaches the target position, voltage is applied to the motor 107 to generate torque for the reverse rotation of the motor 107 so as to reduce the rotation speed of the motor 107 . In this operation of the motor 107 , the counter-electromotive force is further added to the applied voltage, and the overcurrent flow may occur in the drive circuit of the motor 107 . [0063] For example, FIG. 14 shows the induced counter-electromotive force and the current flow in the motor 107 used in the electric-control-type throttle apparatus. [0064] In FIGS. 9A and 9B respectively, a schematic diagram of the composition of the drive circuit 68 , and an example of the voltage pulse pattern applied to the switching elements are shown. Moreover, FIG. 10 shows the voltage generated at the motor 107 and the current flow in the switching elements of the drive circuit when the voltage is applied to the motor 107 to generate torque for the reverse rotation of the motor 107 . M 1 , M 2 , M 3 , and M 4 indicate the switching elements using FETS, and turn current fed to the motor 107 on or off. By turning on M 1 and M 4 (M 2 and M 3 being turned off), the motor 107 is rotated in the forward (valve opening) direction. On the other hand, in turning on M 2 and M 3 (M 1 and M 4 being turned off), the motor 107 is rotated in the reverse valve closing) direction. When the motor 107 rotates in the reverse direction, the counter-electromotive force of the motor 107 is generated in the direction in which the side A of the motor 107 is positive. In order to rapidly decelerate the reverse rotation speed of motor 107 , the voltage in the forward direction is applied to the motor 107 by turning on M 1 and M 4 as shown in FIG. 10. Consequently, the direction of the generated counter-electromotive force V m coincides with that of the applied voltage V b (E), and the current i m flows in M 1 and M 4 . The flowing current is larger by the amount of the current generated by the counter-electromotive force V m than the current generated by only the applied voltage V b . If the current i m exceeds the permitted value of the switching elements M 1 , M 2 , M 3 , and M 4 that is, the current i m is overcurrent, and the switching elements M 1 and M 4 possibly break down. [0065] In this embodiment, by adequately setting the impedance of the motor 107 , overcurrent flow in the drive circuit 68 and the motor 107 due to the counter-electromotive force can be prevented. [0066] The impedance of the motor 107 is determined so as to satisfy the above-described inequality (2). The inequality (2) is again described below. R m > ( E + K e  θ . m ) I lim , ( 2 ) [0067] where θ m =ι v ·N, and V m =K e θ m , and R m is the motor impedance [Ω], E: the voltage applied to the motor 107 [V], K e : the induction voltage constant [V/rpm], θ m : the rotation speed of the motor 107 [rpm], θ v : the rotation speed of the throttle valve 102 [rpm], N: the speed-reducing ratio, and V m the counter-electromotive force induced in the motor 107 . [0068] The right-hand side of the inequality (2) expresses the resistance obtained by dividing the sum of the applied voltage V b and the counter-electromotive force V m by the permitted current I lim . [0069] This impedance R m . is the impedance between A and B shown in FIG. 9A, that is, both terminals of the motor 107 , including not only the armature impedance of the motor 107 , but also the impedance of a choke coil used as a noise filter and the brush resistance. [0070] Furthermore, the resistance component of the impedance is obtained by measuring current flowing in the motor 107 when the voltage (13 V in this embodiment) is applied and the motor 107 has stalled. Hereafter, concerning the impedance of the motor 107 , the resistance component is mainly considered (R m is described as the resistance ). [0071] If the resistance R m does not satisfy the inequality (2), the resistance R m is an insufficient value, and the current flowing in the drive circuit 68 may exceed its permitted value. In determining the adequate value of the resistance R m , the right-hand side of the inequality (2) is conservatively estimated at the temperature of −30° C. at which the resistance R m has the minimal value in the assumed temperature range of the vehicle operation. That is, the right-hand side of the inequality (2) is estimated by using parameters expressing the characteristics of the motor 107 at the temperature −30° C. The rotation speed θ v is defined as the speed 187.5 rpm in rotating the throttle valve from 0 degree to 90 degree (π/2) by 80 ms. [0072] Furthermore, in this embodiment, the gear ratio N is 10.28, and the induction voltage constant K e is 3.92 V/krpm. The applied voltage E is almost 13 V, which is generated by a battery ordinarily used in a vehicle. Although the voltage of the battery is controlled so as to be in the range of 12.7-12.8 V, sometimes the power decreases below 10 V a vehicle is started, or in the dissipated state of the battery. Moreover, the voltage of the battery sometimes increases to over 16 V due to the malfunction of a battery voltage control apparatus. However, in estimating the right-hand side of the inequality (2), the voltage 13 V usually used in an engine of a vehicle is used. Also, as the permitted current of the switching elements in the drive circuit 68 of the motor 107 , 20 A is used. By substituting the above values into the right-hand side of the inequality (2), it is found that the resistance R m of more than 1.03 Ω satisfies the inequality (2). Furthermore, because it can occur by an error in production that the resistance R m takes a 5% lower value, and the induction voltage constant K e takes a 10% higher value than the nominal value, the right-hand side of the inequality (2) is estimated taking the above error into account. Thus, by using the increased value 4.31 V/krpm for the induction voltage constant K e, the resistance R m is estimated as a value higher than 1.12 Ω. Thus, in this embodiment, the resistance R m is conservatively set as 1.3 Ω. [0073] In the above-mentioned example, the operation time in which the throttle valve 102 is driven from the minimum opening to the maximum opening is set as 80 ms. In order to determine the resistance R m more precisely, the following method can be used. That is, the operation time t of the throttle valve 102 is obtained by using the above-described equation (1) (as the parameters expressing the characteristics of the motor 107 , their values at not 120° C. but −30° C. are used), and the resistance R m can be also determined with the rotation speed θ v of the valve 102 calculated by using the above-obtained operation time t. By using this method of determining the resistance R m , the breakdown of the switching elements in a drive circuit can be prevented even in an electric-control-type throttle apparatus in which the operation time t is much shorter than 80 ms. However, in the above method, because the parameters of the motor at −30° C. are used, it may occur that the determined resistance R m is too large at the operating temperature, which in turn decreases the current flowing in the motor 107 too much, and the output torque of the motor 107 becomes insufficient. Consequently, the response of the electric-control-type throttle apparatus deteriorates. Moreover, the delay effect of a control system is not considered in the equation (1). If the very quick response of the electric-control-type apparatus is intended, this delay effect cannot be neglected. [0074] Accordingly, it is more appropriate that the necessary resistance R m at 20° C. is determined with the inequality (2) by using the operation time t of the valve 102 , which is obtained by using the equation (1) in which the parameters expressing the characteristics of the motor 107 at 20° C. are used. As for the operation time t of 40 ms (375 rpm), it is seen in FIG. 5A that the adequate gear ratio N is about 10 at 20° C. Consequently, the resistance R m at 20° C., satisfying the inequality (2), is estimated as more than 1.35 Ω. Furthermore, by taking the error of the quantity production into account, it is preferable to set the resistance as more than 1.49 Ω. In this embodiment, the resistance R m at 20° C. is more conservatively set at 1.61 Ω. [0075] According to the above method of determining the resistance R m , the current flowing in the motor 107 and its drive circuit 68 is restricted so as not to exceed the permitted value, and it is possible to reduce the probability of the breakdown of the switching elements in the drive circuit 68 without using a complicated circuit or control method. [0076] Other methods in which the value of the right-hand side of the inequality (2) is always monitored and the applied voltage is controlled so as to satisfy the inequality (2) are also effective in preventing the breakdown of the switching elements. A system for implementing the above method is shown in FIG. 6. In one of the above methods, a control circuit 63 calculates the rotation speed of the motor 107 based on the change rate in time of the target opening, and monitors and predicts the value of the right-hand side of the inequality (2). Moreover, it controls the voltage applied to the motor 107 so as to satisfy the inequality (2). If the rotation speed of the motor 107 is high and the value of the right-hand side of the inequality (2) is predicted to exceed the value satisfying the inequality (2), the sum of the applied voltage V b (E) and the counter-electromotive force V m is decreased by decreasing the applied voltage, particularly when it begins to apply the reverse voltage to the motor 107 . In another one of the above methods, the voltage between the terminals A and B of the motor 107 (counter-electromotive force) is monitored, and the control circuit 63 always calculates the sum of the applied voltage V b (E) and the counter-electromotive force V m . Moreover, if the rotation speed of the motor 107 is high and the value of the right-hand side of the inequality (2) is predicted to exceed the value satisfying the inequality (2), the control circuit 63 stops applying the voltage to the motor 107 . In another of the above methods, the control circuit 63 always monitors the value obtained by dividing the sum of the applied voltage V b (E) and the counter-electromotive force V m by the resistance R m , and if the value is predicted to exceed the permitted current, the control circuit 63 stops applying voltage to the motor 107 briefly, and then start applying voltage to the motor 107 again. [0077] Each of the above-mentioned methods can be implemented by a simple circuit, and because it is not necessary to use a motor of a large resistance R m , the heat (joule heat) generated in the coils of the motor 107 can be reduced. Moreover, because it is possible to always flow current at a level near the permitted current, the operation time of a throttle valve 102 can also be reduced. [0078] As for the gear ratio, it is set as 10.28 in this embodiment. By using this gear ratio, it becomes possible not only to secure the stable response of the electric-control-type throttle apparatus, which is not affected by the dispersion in the characteristics of the motor 107 and the spring force of the default mechanism or by load torque changes due to the deposit on the throttle valve 102 , but also to operate the throttle valve 102 at a relatively high speed. [0079] Meanwhile, the gear ratio 10.28 is determined by the tooth numbers of the respective motor gear 106 , large intermediate gear 104 a, small intermediate gear 104 b, and valve gear 103 shown in FIG. 1 and FIG. 8. The respective tooth numbers are 21 , 65 , 22 , and 73 (this value is converted to the all-around tooth number) for motor gear 106 , the large intermediate gear 104 a, the small intermediate gear 104 b, and the valve gear 103 respectively. It is not always necessary to use those tooth numbers for implementing the present invention. Moreover, the target gear ratio cannot be always precisely realized. The reason is that the tooth number of a gear depends on the distance between the shaft of each gear and that of a gear or gear module neighboring the gear, and those distances are also restricted by the size of each gear. Therefore, it is practical to set the gear ratio in the range of 9.80 to 10.78, which is determined by taking the variation caused by one tooth in the teeth of each gear into account rather than to set the ratio at one value of 10.28. [0080] In the electric-control-type throttle apparatus, if the gear ratio is set low, it is difficult to stably operate the throttle apparatus because the spring force of the default mechanism becomes large relative to the torque of the motor 107 , which makes the change in the operation time sensitive to the change of the torque of the motor 107 . Furthermore, the equivalent moment of inertia of the throttle valve 102 to be driven by the motor 107 becomes relatively large, which degrades the response of the throttle apparatus. [0081] Conversely, if the gear ratio is set high, it takes more time to accelerate the motor 107 because it is necessary to rotate the motor 107 at a high speed in order to obtain the quick response of the throttle apparatus. Thus, the response of the throttle apparatus is deteriorated, which is not preferable for a direct-injection engine. [0082] [0082]FIG. 11 shows an illustration to explain the motion of the electric-control-type throttle apparatus. When the motor 107 generates the torque T m , the gears rotate and reduce the rotation speed that is transmitted from the rotation speed of the motor 107 to the valve shaft 108 by the degree of the ratio N, and rotates the throttle valve 102 to which the spring load T s is applied. Equations of motion in a system shown in FIG. 11 are expressed by the following equations (3): J     θ ¨ v + T s = T m  N      To = K m  I L m  I + R m  I + K e  N     θ . v = E } , ( 3 ) [0083] where To : the torque of the motor [Nm], K m : the torque constant [Nm/A], I: current flow in the motor [A], and L m : the inductance of the motor [H]. [0084] The above equations (3) express the mechanical motion, the torque generated in the motor, and the voltage relation, respectively. It is seen that smaller values of the moment of inertia J, the inductance L m , the resistance R m , and the preload torque T s of the return spring 111 move the throttle valve more quickly. Thus, the values of the torque constant K m , the induction voltage constant K e , and the gear ratio N should be optimized. [0085] The gear ratio N used in this embodiment is determined so as to realize the stable and quick operation of the electric-control-type throttle apparatus. To determine this gear ratio N, the equation (1) is used. The equation (1) is again described below. t = π ( T max  N - T s ) J , ( 1 ) [0086] where T max =K m E/R m and T s : the preload of the return spring 111 of the force applying means [Nm], T max : the torque of the motor 107 [Nm], N: the speed-reducing ratio, J:the equivalent moment of inertia [kgm 2 ], K m : the torque constant [Nm/A], R m : the resistance of the motor 107 [Ω], and E: the voltage applied to the motor 107 [V]. [0087] The equation (1) is obtained by neglecting both the inductance L m that slightly affects the motion of the system, and the transient effects in the motion of the motor 107 , assuming that the torque To approximately reaches the maximum value T max ; and by integrating the equations (3). Although the equation (1) is an approximate equation which does not include the delay effect of a control system, the response performance of the control system can be designed to be sufficiently quick if a mechanical system can be operated quickly enough. Therefore, in this embodiment, the equation (1) expresses a value close to the accurate operation time t of the throttle valve 102 . [0088] In estimating the operation time t by using the equation (1), it is assumed that the throttle valve 102 is rotated by the angle π/2 from the minimum opening to the maximum opening. Because the torque generated by the motor 107 decreases when the temperature of the motor 107 increases, the values at 120° C. concerning the parameters are used in the right-hand side of the equation (1) by assuming that this electric-control-type throttle apparatus is left in the environment of 120° C. for a long time and that the temperature of the apparatus reaches its equilibrium state. As the moment of inertia J, the equivalent moment is used: that is, the moment obtained by combining and converting the moment of inertia of the motor 107 and the moment of inertia of the respective gears into one lump of moment of inertia attached to the valve shaft 108 . Also, the value 13 V which is the voltage of an ordinarily used battery is used as the applied voltage, [0089] To realize the high speed operation of the electric-control-type throttle apparatus, it is desirable that the operation time t estimated by the equation (1) is less than 80 ms. Because the characteristics of the motor 107 cannot be freely changed, the operation time t is adjusted by changing the gear ratio N, based on the selected specification parameters of the motor 107 . In the following, the gear ratio (speed-reducing ratio) will be explained. FIG. 5A shows the relationship between the operation time t estimated by using the equation (1) and the gear ratio (speed-reducing ratio). From this figure, it is seen that the operation time t gradually changes in the range of the gear ratio N from 2.5 to 32. On the other hand, the operation time t rapidly changes below the gear ratio 2.5, and the stable operation of the throttle valve 102 becomes difficult because the spring load of the return spring 111 becomes relatively large. In the range of the gear ratio of 2.5 to 5, the change in the operation time t is sensitive to the change in the gear ratio. This situation is similar to the change in the load of the motor 102 . That is, the operation time t mainly changes relative to small changes in the load. Two dotted lines shown in FIG. 5A indicate the best and worst estimated operation times t when the induction voltage constant K e and the resistance R m of the motor at 120° C. change by 10% and 5%,respectively, which are caused by an error in the quantity production. From those lines, the change in the operation time t is sensitive also to changes in the characteristic parameters of the motor 107 below the gear ratio 5 . [0090] [0090]FIG. 5B shows changes in the operation time t corresponding to changes in the temperature at the gear ratios 3 and 10 . The gradient of the line at the gear ratio 3 is larger than that at the gear ratio 10 , that is, the change in the operation time t at the gear ratio 10 is less sensitive to a change in the temperature than that at the gear ratio 3 . The lower sensitivity to the temperature is more favorable for controlling the throttle apparatus because control becomes easier. Therefore, the control performance at the gear ratio 10 is superior to that at the gear ratio 3 . The specification parameters which change correspondingly with the change in the temperature are mainly the torque constant and the resistance of the motor 107 . Accordingly, if the temperature is high, the torque generated in the motor 107 is small, and vice versa. Furthermore, the change in the temperature can be replaced with the change in the torque generated in the motor. Consequently, it can be said that, at the small gear ratio, the change in the operation time t is large relative to the change in the torque generated by the motor 107 (the change in the temperature). Considering the small gear ration from another view point, because the small gear ratio means that the torque transmitted to the valve shaft 108 of the throttle valve 102 is small, it can be also said that the operation time t becomes sensitive to a change in the load applied to the valve shaft 108 if the gear ratio is small. Thus, the large gear ratio brings the stable operation time t, and is advantageous to the control of the electric-control-type throttle apparatus. In showing the dependency of the operation time t on the temperature in FIG. 5B, the values 3 and 10 of the gear ratio are selected as typical values. The gear ratio 3 is in the region of the negative gradient of lines expressing the dependency of the operation time on the gear ratio shown in FIG. 5A, and the gear ratio 10 is in the region of the positive gradient of those lines shown in FIG. 5A. As shown by the line at the gear ratio 3 in FIG. 5B, the tendency in which the operation time t largely changes along with the change in the temperature occurs in the negative region of those lines shown in FIG. 5A. Therefore, in determining the gear ratio, it is desirable to select the gear ratio in the region of the positive gradient of those lines in FIG. 5A, in which the operation time t is comparatively insensitive to the change in the temperature (namely, torque and load). [0091] In this embodiment, the gear ratio is determined within the range of the positive gradient of those lines shown in FIG. 5A. It is because, as mentioned above, the change in the operation time t is small relative to the change in the load or the change in the characteristics of the motor 107 in this region of the gear ratio and the stable operation of the throttle valve 102 can be maintained. [0092] By selecting the above-mentioned gear ratio, when the electric-control-type throttle valve of the present invention is applied to a direct-injection engine, it is possible to realize a quick response with only minimal changes in the output power of the engine even when switching the burning mode. [0093] In FIG. 7, output power changes in a direct-injection engine, which occur when switching the burning mode, are shown with respect to the operation time t. From this figure, it is seen that the output power changes when switching the burning mode are comparatively low in the range below the operation time of 80 ms. The reason will be explained in the following. [0094] The electric-control-type throttle apparatus 61 of this embodiment is arranged in the upper stream of the air intake pipe of the engine 62 as shown in FIG. 6. Therefore, even if the throttle valve 102 is driven rapidly, the actual flow rate of the intake air into the engine 62 is delayed by the volume of a manifold part from the exit of this throttle apparatus 61 to the entrance of the engine 62 . Thus, even if the throttle valve 102 is instantaneously driven from the fully open state to the fully closed state within, for example, 10 ms, the flow rate of the intake air into the engine 62 does not instantaneously become 0, but gradually decreases to 0. In FIG. 13, the change in the flow rate of the intake air in instantaneously opening the throttle valve 102 from the fully closed state to the fully open state is shown until the flow rate reaches the rated value 100%. The delay time τ depends on the ratio of the volume of the manifold part of the air intake pipe to the engine swept volume and the rotation speed N e of the engine 62 , and this delay time τ is obtained by the following equation (4): τ=120·V man /(V d ·N e )   (4), [0095] where V man : the volume of the manifold part from the exit of this throttle apparatus 61 to the entrance of the engine 62 [L], V d : the engine swept volume [L], and N e : the rotation speed of the engine 62 . [0096] The ratio of the V m /V d is generally about 0.8-1.5. The delay time τ is defined as the time at which the flow rate reaches the value of 63% of the rated flow rate, and the response time at which the flow rate effectively reaches 100% is defined as the time at which the dotted line connecting the original point and the point of 63% intersects the horizontal line of 100% in FIG. 13. The response times are calculated by varying the ratio V m /V d and the rotation speed N e . Results of the calculation are summarized in Table 2. [0097] Switching the burning mode in a direct-injection engine is carried out within the range of 2000 rpm to 3000 rpm. In this range, the minimum response time necessary for the flow rate to reach time under the conditions of Ne: 3000 rpm and the ratio V m /V d : 0.8 is 51 ms, and the maximum response time under the conditions of Ne: 2000 rpm and the ratio V m /V d : 1.5 is 143 ms. TABLE 2 Rotation The ratio of the air intake pipe volume to the speed N e of engine swept volume [V man /V d ] engine [rpm] 0.8  1.0 1.2 1.5 1000  0.152* 0.190 0.229 0.286 1500 0.102 0.127 0.152 0.190 2000 0.076 0.095 0.114 0.143 2500 0.061 0.076 0.091 0.114 3000 0.051 0.063 0.076 0.095 4000 0.038 0.048 0.057 0.071 5000 0.030 0.038 0.046 0.057 [0098] However, it is rare for the burning mode to be switched near the rotation speed 3000 rpm, and the ratio V m /V d is usually more than 1.0. Therefore, the operation time of the throttle valve 102 is preferably set less than 100 m when applying the throttle apparatus to a direct-injection engine in which the burning mode is switched near the rotation speed 2000 rpm. If the throttle apparatus can realize the operation time t of less than 80 ms, it can be applied to almost all direct-injection engine. In this embodiment, the ratio V m /V d is about 1.0, and the rotation speed when switching the burning mode is about 2500 rpm. By using the electric-control-type throttle apparatus, the operation time of 80 ms is almost equal to the response time of the flow rate in the lower stream region (manifold part) of the air intake pipe. Thus, because the flow rate of the intake air into the engine 62 can be controlled at a high speed, the change in the output power of the engine 62 can be reduced as shown in FIG. 7. [0099] Furthermore, in the electric-control-type throttle valve, it is a characteristic particular to this type of throttle apparatus that the throttle valve must be released from its sticking state due to the soil deposit caused by the adhesion of gum-state substances. Especially in this embodiment which does not use the pedal operation transmission mechanism in which the throttle valve 102 is directly driven by a wire connected to the acceleration pedal operated by a driver, the sticking state of the throttle valve 102 must be released by only the torque of the motor 107 . Although the sticking force varies depending on the operation environment of the throttle valve 102 , if the torque of more than 110 kgfmm can be applied to the shaft of the throttle valve 102 , this torque is sufficient to release almost all of the assumed sticking states. [0100] The excess quantity of the torque which can be applied to the valve shaft 108 beyond the preload torque of the return spring 111 at the default position of the throttle valve 102 is called the sticking release torque. That is, the sicking release torque is the difference between the torque applied to the valve shaft 108 by the motor 107 and the preload torque of the return spring 111 . The gum-state substances causing the sticking state of the throttle valve 102 are softened at a high temperature. On the other hand, because the maximum torque generated by the motor 107 increases when the temperature decreases, it is appropriate to estimate the sticking release torque at the ordinary temperature (20° C). Moreover, it is assumed that the sticking of the throttle valve 102 occurs during a long-term stoppage of the vehicle, for example, parking for a long time, which possibly causes the decrease of the voltage V b of the battery. Therefore, as the voltage V b of the battery, the value of 10 V is used to conservatively estimate the sticking release torque brought by the motor 107 . In this embodiment, the maximum torque generated by the motor 107 is 21.9 kgfmm at the applied voltage E of 10 V, the gear ratio N is 10.3, and the preload torque of the return spring 111 is 36 kgfmm. Therefore, the sticking release torque (190 kgfmm) applied to the valve shaft 108 is larger by about 80 kgfmm than the necessary sticking release torque 110 kgfmm. Therefore, the sticking release torque is sufficiently secured in this embodiment, and the electric-control-type throttle apparatus of this embodiment is powerful against the sticking of the throttle valve 102 , which improves the reliability the throttle apparatus. [0101] [0101]FIG. 15 shows the relationship between the limit values of the motor resistance R m and the values of the torque constant K m under the conditions of each value at the operation time of 80 ms, the necessary sticking release torque of 110 kgfmm, and the permitted current of 20 A. The equivalent moment of inertia J is set as 0.0013 kgm 2 . [0102] In FIG. 15, the solid line A indicates the upper limit values of the motor resistance R m such that the operation time of the throttle valve 102 is less than 80 ms. It is desirable to set the torque constant K m and the motor resistance R m as values in the lower side region of the line A. The solid line C indicates the lower limit values of the motor resistance R m such that the peak current flow in the motor 107 is less than the permitted current 20 A. Accordingly, it is desirable to set the torque constant K m and the motor resistance R m as values in the upper side region of the line C. Consequently, it is desirable to set the torque constant K m and the motor resistance R m as values in the region between the lines A and C. As to the torque constant K m , because the electromagnetic force of the motor 107 should be increased to satisfy the value of greater than 0.04 Nm/A, which increases its production cost and its size, the value of less than 0.04 Nm/A is desirable although it is possible to set the torque constant K m to a value of more than 0.04 Nm/A . On the other hand, if the torque constant K m is less than 0.025 Nm/A, it is necessary to have a large current flow in the motor 107 , and the influence of the production error of the motor resistance R m becomes relatively large. Therefore, the region surrounded by a pair of dotted lines and the line A and C is a desirable region to set the torque constant K m and the motor resistance R m . [0103] Furthermore, the upper limit values of the motor resistance R m such that the sticking release torque is more than 110 kgfmm are indicated by the line B in FIG. 15. In order to secure a sticking release torque of more than 110 kgfmm, it is necessary to set the torque constant K m and the motor resistance R m in the lower region of the line B. Thus, the shadowed region surrounded by a pair of dotted lines and the line A and C becomes a more appropriate region to set the torque constant K m and the motor resistance R m . In this embodiment, taking the error in the production into account, the torque constant K m and the motor resistance R m are set within 0.03-0.037 Nm/A and within 1.29-2.24 Ω, respectively. [0104] As a typical example of the specification parameters for the electric-control-type throttle apparatus, in this embodiment, the following values are set: that is, the torque constant K m of 0.035±0.0035 Nm/A, the motor resistance R m of 1.61±0.08 Ω, and the speed-reducing ratio N of 10.3 (9.8-10.8). Moreover, by setting the preload torque of the return spring 111 at 0.35 (0.3-0.4) Nm, the operational safety of the vehicle to which the electric-control-type throttle valve of the present invention is applied is secured because the position of the throttle valve 102 is automatically returned to the predetermined opening position even if the motor 107 fails. [0105] By using the electric-control-type throttle apparatus of the present invention, it is possible to operate the throttle valve 102 at a high speed, which can reduce the change in the output power of the engine 62 even when switching the burning mode from the stratified charge burning mode to the uniform mixture charge burning mode in the direct-injection engine. Furthermore, it is possible to prevent the overcurrent flow in the drive circuit 68 when operating the throttle valve 102 at a high speed that is, the burning of the switching elements in the drive circuit 68 can be prevented, which improves the fail-safe performance of the throttle apparatus. [0106] Although the voltage 13 V is used as the applied voltage E in the above embodiments, other values of the applied voltage E are applicable.
An electrically-controlled throttle valve apparatus includes a motor, a speed reducing mechanism for reducing rotation speed transmitted from the motor, a throttle valve connected to the speed reducing mechanism, and a force applying device applying force to the throttle valve in the direction of returning the valve to its initial position and adjusting the opening of the throttle valve by driving the motor. Parameters of the motor, the speed reducing mechanism, and the force applying device have values such that the operation time t from the minimum to the maximum throttle valve opening, which is determined by an evaluation equation obtained from equations of throttle valve motion, is less than a prescribed target throttle valve operation time t★. Furthermore, resistance and an induction voltage constant of the motor are determined to satisfy a constraint equation obtained based on Ohm's law.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "BACKGROUND OF THE INVENTION [0001] The present invention relates to an electric-control-type throttle apparatus for controlling the amount of intake air, used in an internal combustion engine.", "[0002] Japanese Patent Publication 177534/1996 discloses a throttle valve control apparatus including a throttle body, a throttle valve installed in the air intake path of the throttle body via a rotatable shaft, an actuator for driving the throttle valve via a plurality of gears, and a detection means for detecting the rotation angle of the throttle valve.", "[0003] The plurality of gears of this apparatus is composed of the first gear fixed to the shaft of the throttle valve, the third gear fixed to the rotation shaft of the motor used as the actuator, and the second gear between the first and third gears.", "This composition can increase the speed reducing ratio, which can finely control the opening of the throttle valve.", "[0004] Although the opening of the throttle valve can be finely controlled by obtaining a large gear ratio in the above-mentioned conventional throttle apparatus, it is not stated how to determine the characteristics of the motor, or the gear ratio with which the torque of the motor is transmitted to the throttle valve in order to realize the desired operation speed of the throttle valve.", "[0005] In the above conventional apparatus, the throttle valve is opened or closed by the motor.", "If the opening or closing of the throttle valve does not respond quickly to the motion of the acceleration pedal operated by a driver, the driver notices the gap between the operations performed by the driver itself and changes in the operational state of the internal engine.", "However, in the electric-control-type throttle apparatus, it is necessary to provide a force applying means for quickly returning the position of the throttle valve to the predetermined opening in the event of a problem with the fail-safe operation.", "Therefore, the operation speed of the throttle valve cannot easily be increased, and it is important to adequately determine the force from the force applying means, the performance of the motor, and the speed reducing ratio of the rotation speed of the motor to that of the throttle valve.", "[0006] If this conventional throttle apparatus is applied to a direct injection engine in which fuel is directly injected in each cylinder, the following problems will occur.", "[0007] In a conventionally used port injection engine in which fuel is injected into an air intake pipe, the engine is operated near the theoretical air to fuel ratio of 14.7.", "On the other hand, a direct injection engine is operated in a wide range of an air to fuel ratio of 14.7 (theoretical ratio) to more than 40 (superlean ratio).", "Fuel burning near the theoretical air to fuel ratio is called the uniform mixture charge burning state, and fuel burning at an air to fuel ratio higher than the theoretical ratio is called the stratified charge burning state.", "It is easy to realize the stratified charge burning state in a direct injection engine because fuel is directly injected into a cylinder.", "FIG. 12 is a diagram showing the relationship between the fuel burning modes and operation states of an engine.", "The stratified charge burning mode is performed below an engine rotation speed of approximately 3000 rpm.", "[0008] In implementing those burning modes, it is necessary to open the throttle valve wider in the stratified charge burning state than in the uniform mixture charge burning state.", "Therefore, when the operation of the engine is changed from the stratified charge burning state to the uniform mixture charge burning, the throttle valve is driven in the valve closing direction.", "FIG. 4A and FIG. 4B show changes in time of the actuating amount of an acceleration pedal and changes in time of the opening of the throttle valve corresponding to the changes of the actuating amount of the acceleration pedal, respectively.", "[0009] As shown in FIG. 4B, the throttle valve is widely opened in the stratified charge burning state, and it is driven once in the valve closing direction when the operation of the engine is switched to the uniform mixture charge burning state.", "If the time necessary for the switching operation is long, the switching operation between the two burning states cannot be smoothly carried out, and the output power of the engine rapidly changes.", "Consequently, a shock caused by the switching operation is transmitted to the passengers and the driver of the vehicle, which degrades both the operationality of the vehicle and the comfort of riding in the vehicle.", "[0010] On the other hand, if the throttle valve is driven at a high speed, it is also necessary to rotate the motor driving the throttle valve at a high speed.", "In these high speed operations, the higher speed the motor is rotated at, the larger the counter-electromotive force for braking the rotation of the throttle valve becomes.", "Therefore, there may be a large current that is beyond the permitted value for the switching elements used in a drive circuit for driving the motor.", "It is then necessary to use switching elements with the higher permitted current value for the drive circuit of the motor.", "However, switching elements with the required larger permitted current cannot be always acquired.", "Even though switching elements with the required larger permitted current can be acquired, such elements are very expensive and unsuitable for use in a vehicle.", "For another means for restricting the value of the current flowing in the drive circuit of the motor below the permitted current value, it is also possible to provide a current limiting circuit in the drive circuit.", "However, this means increases the production cost, and if the provided current limiting circuit breaks down, it is possible that the increased current cannot be kept below the permitted current value.", "Thus, this means does not offer a sufficient fail-safe function.", "SUMMARY OF THE INVENTION [0011] An objective of the present invention is to realize a highly reliable electric-control-type throttle apparatus capable of performing the usual opening and closing operations and offering a fail-safe function of securing the position of a throttle valve at which a vehicle can be safely driven at an appropriate operation speed even in the event of a failure of the motor for driving the throttle valve.", "[0012] The first feature of the present invention designed to attain the above objective is to provide an electric-control-type throttle apparatus including a motor, a speed reducing mechanism for reducing the rotation speed that is transmitted from the rotation speed of the motor, a throttle valve connected to the speed reducing mechanism, and a force applying means for applying force to the throttle valve towards returning the valve to its initial position, for adjusting the opening of the throttle valve by driving the motor;", "wherein the specification parameters of the motor, the speed reducing mechanism, and the force applying means have their values such that the operation time t from the minimum opening to the maximum opening of the throttle valve, which is determined by the following equation (1): t = π ( T max  N - T s ) J , ( 1 ) [0013] where T max =K m E/R m and T s : the preload of a return spring of the force applying means [Nm], T max : the torque of the motor [Nm], N: the speed reducing ratio, J: the equivalent moment of inertia [kgm 2 ], K m the torque constant [Nm/A], R m : the impedance of the motor [Ω], and E: the voltage applied to the motor [V], [0014] is shorter than a prescribed target operation time t★.", "[0015] The second feature of the present invention is that, in the above electric-control-type throttle apparatus of the first feature, the target operation time t★ is 80 ms.", "[0016] The third feature of the present invention is that, in the above electric-control-type throttle apparatus of the second feature, the values of the specification parameters are those at the temperature of 120° C. [0017] The fourth feature of the present invention is that, in the above electric-control-type throttle apparatus of the second feature, the applied voltage is approximately 13 V. [0018] The fifth feature of the present invention is that, in the above electric-control-type throttle apparatus of the second feature, the torque constant K m is 0.035±0.0035 Nm/A, the resistance of the motor R m is 1.6±0.1 Ω, and the speed reducing ratio N is from 9.8 to 10.8, preferably 10.3 at the temperature 20° C. [0019] The sixth feature of the present invention is that, in the above electric-control-type throttle apparatus of the fifth feature, the preload torque T s of the return spring is from 0.3 to 0.4 Nm, preferably 0.35 Nm.", "[0020] The seventh feature of the present invention is that, in the above electric-control-type throttle apparatus of the second feature, the torque constant K m is from 0.025 to 0.04 Nm/A, preferably from 0.03 to 0.037 Nm/A, and the resistance of the motor R m .", "is from 1.0 to 2.5 Ω, preferably from 1.3 to 2.2 Ω.", "[0021] The eighth feature of the present invention is that, in the above electric-control-type throttle apparatus of the first feature, the specification parameters have values such that a differential coefficient of the operation time t expressed by the equation (1) with respect to the speed reducing ratio N is positive.", "[0022] The ninth feature of the present invention is that, in the above electric-control-type throttle apparatus of the eighth feature, the speed reducing ratio N is from 9.8 to 10.8.", "[0023] The tenth feature of the present invention is that the above electric-control-type throttle apparatus of the first feature further includes a detector for detecting the applied voltage E, a means for measuring the counter-electromotive force induced in the motor, and a control unit for controlling the motor, wherein the control unit predicts changes in the value obtained by dividing the sum of the detected applied voltage E and the measured counter-electromotive force by the impedance R m of the motor, and controls the applied voltage so as not to flow current beyond the permitted current value in the circuit used for driving the motor.", "[0024] The eleventh feature of the present invention is to provide an electric-control-type throttle apparatus including a motor, a speed reducing mechanism for reducing the rotation speed that is transmitted from the rotation speed of the motor, a throttle valve connected to the speed reducing mechanism, and a force applying means for applying force to the throttle valve towards returning the valve to its initial position, and adjusting the opening of the throttle valve by driving the motor;", "wherein the specification parameters of the motor, and the force applying means have their values satisfying the following inequality (2): R m >", "( E + K e  θ .", "m ) I lim , ( 2 ) [0025] where θ m =ι v ·N, and V m =K e θ m , and R m is the resistance of the motor [Ω], E: the voltage applied to the motor [V], K e : the induction voltage coefficient [V/rpm], θ m : the rotation speed of the motor [rpm], θ v : the rotation speed of the throttle valve [rpm], N: the speed reducing ratio, and V m : the counter-electromotive force induced in the motor.", "[0026] The twelfth feature of the present invention is that, in the above electric-control-type throttle apparatus of the eleventh feature, the applied voltage E is approximately 13 V, and the motor impedance R m is more than 1.2 Ω at 20° C. [0027] The thirteenth feature of the present invention is that the above electric-control-type throttle apparatus of the eleventh feature further includes a detector for detecting the applied voltage E and a control unit for controlling the motor, wherein the control unit predicts changes in the value of the right-hand side of the inequality (2) and controls the applied voltage E so as to always satisfy the inequality (2).", "[0028] The fourteenth feature of the present invention is that, in the above electric-control-type throttle apparatus of the first to thirteenth features, the throttle apparatus is used in a direct-injection combustion engine.", "BRIEF DESCRIPTION OF THE DRAWINGS [0029] [0029 ]FIG. 1 is a horizontal section of an electric-control-type throttle apparatus of an embodiment according to the present invention.", "[0030] [0030 ]FIG. 2 is an illustration showing the principle of a default mechanism.", "[0031] [0031 ]FIG. 3 is an illustration for showing the force applied to the shaft of a throttle valve by a return spring and a default spring.", "[0032] [0032 ]FIGS. 4A and 4B show operations of a throttle valve in an electric-control-type throttle apparatus, corresponding to changes in time of the actuating amount of an acceleration pedal.", "[0033] [0033 ]FIGS. 5A and 5B show the relationship between the operation time t, and the speed reducing ratio and temperature, respectively.", "[0034] [0034 ]FIG. 6 is a schematic diagram showing the composition of a direct-injection engine using an electric-control-type throttle apparatus.", "[0035] [0035 ]FIG. 7 is a diagram showing changes of the output power of a direct-injection engine when the fuel burning mode is switched.", "[0036] [0036 ]FIG. 8 is a front view of the electric-control-type throttle valve shown in FIG. 1, which is viewed from the direction of the shaft of the throttle valve.", "[0037] [0037 ]FIGS. 9A and 9B show a drive circuit for driving the motor and voltage pulse patterns applied to the drive circuit, respectively.", "[0038] [0038 ]FIG. 10 is a conceptual diagram showing a current flow path when voltage is applied to the motor to cause the torque in a direction inverse to that of the present rotation of the motor.", "[0039] [0039 ]FIG. 11 is a diagram for explaining the motion of the electric-control-type throttle apparatus.", "[0040] [0040 ]FIG. 12 is a diagram showing the relationship between the fuel burning modes and operation states of an engine.", "[0041] [0041 ]FIG. 13 shows a delay in the response of the intake air flow rate to a step change of the opening of a throttle valve.", "[0042] [0042 ]FIG. 14 shows the induced counter-electromotive force and the current flowing in the motor used in the electric-control-type throttle apparatus.", "[0043] [0043 ]FIG. 15 shows the relationship between the limit values of the motor resistance and the values of the torque constant under the condition of each value of the operation time of 80 ms, the necessary sticking release torque of 110 kgfmm, and the permitted current of 20 A, in which the equivalent moment J of inertia is set 0.0013 kgm 2 .", "DETAILED DESCRIPTION OF THE EMBODIMENTS [0044] Hereinafter, details of embodiments will be explained with reference to the drawings.", "[0045] [0045 ]FIG. 1 shows a horizontal section of an electric-control-type throttle apparatus of an embodiment according to the present invention, and FIG. 8 is a front view of a gear part in the electric-control-type throttle valve shown in FIG. 1, which is viewed from the direction of the shaft of the throttle valve.", "[0046] The electric-control-type throttle apparatus comprises a throttle body 101 including an air intake path and a motor 107 generating the torque, a motor shaft 105 of the motor 107 , a motor gear 106 fixed on the motor shaft 105 , a large intermediate gear 104 a engaged with the motor gear 106 , a small intermediate gear 104 b fixed on the motor shaft 105 coaxially with the large intermediate gear 104 a, a valve gear 103 engaged with the small intermediate gear 104 b, a valve shaft 108 on which the valve gear 103 is fixed, a throttle valve 102 screwed to the valve shaft 108 , and a default mechanism using a return spring 111 and a default spring 112 .", "[0047] Specification parameters determining the performance of the electric-control-type throttle apparatus are indicated as follows.", "The specification parameters concerning the motor 107 are the torque constant, the counter-electromotive (induction) voltage constant, the motor inductance, the motor resistances, the voltage applied to the motor 107 , etc.", "Moreover, the specification parameters concerning the mechanical composition are the moment of inertia, the speed reducing ratio (gear ratio), the preload torque of the return spring 111 , and so on.", "[0048] Furthermore, a throttle position sensor 110 for detecting the position of the throttle valve 102 is provided between the default mechanism and the throttle valve 102 .", "[0049] In order to reduce the rotation speed that is transmitted from the rotation speed of the motor 107 to the valve shaft 108 , it is necessary to make the pitch circle diameter of the motor gear 106 smaller than that of the large intermediate gear 104 engaged with the motor gear 106 .", "Also, it is necessary to make the pitch circle diameter of the small intermediate gear 104 b smaller than that of the valve gear 103 engaged with the small intermediate gear 104 b. Because the rotation angle of the throttle valve 102 is at most 90 degrees, it is sufficient that the valve gear 103 rotates for 90 degrees.", "Thus, the valve gear is formed as a fan shape.", "[0050] The large and small intermediate gears 104 a and 104 b are formed by shaping the respective tooth spaces in the same member.", "A hole is made in the center of the intermediate gears 104 a and 104 b, and an intermediate gear shaft 109 is press-fitted through the hole in the throttle body 101 .", "Moreover, in order to reduce the friction and backlashes in the intermediate gears 104 a and 104 b, a dry bearing is inserted between the intermediate gears 104 a and 104 b, and the intermediate gear shaft 109 .", "[0051] A flange is provided at the motor 107 vertically to the motor shaft 105 , and is fixed to the throttle body 101 with two screws.", "In this embodiment, the large intermediate gear 104 a is arranged in a position near the throttle body 101 on the intermediate gear shaft 109 so that the length of the motor shaft 105 is made as short as possible.", "By this arrangement, it is possible to use the motor shaft 105 of a small diameter because of the increased stiffness with the motor shaft 105 .", "Consequently, the moment of inertia can be decreased, which improves the response of the throttle apparatus.", "[0052] [0052 ]FIG. 2 is a illustration showing the principle of the default mechanism.", "In this figure, for simplicity of explanation, the principle is illustrated by imaging that the rotational motion of a lever 204 , the return spring 201 ( 111 ), and the default spring 202 ( 112 ) is converted to the linear motion.", "The lever 204 is connected to the valve shaft 108 , and is driven by the motor 107 .", "When the lever 204 is moved left, the throttle valve 102 is driven in the valve opening direction.", "The default mechanism maintains the throttle valve 102 at the predetermined position (called the default position) by using a pair of springs.", "The default position is set as the position of the throttle valve, such that the vehicle can start without over-speeding.", "The return spring 201 ( 111 ) is attached to a member 203 and the lever 204 is connected to the throttle shaft 108 .", "The default spring 202 ( 112 ) is attached to the member 203 and a body 205 .", "[0053] If the motor 107 stops, the lever 204 is pushed to the member 203 by the return spring 201 , and the member 203 is maintained at the default position by the default spring 202 .", "In the open-position range beyond the default position of the lever 204 , the member 203 touches the body 205 and stops there, and the force is applied to the lever 204 by the return spring 201 in the valve closing direction.", "On the other hand, in the closed-position range below the default position of the lever 204 , the force of the default spring 202 is applied to the throttle valve 102 via the lever 204 and the member 203 .", "[0054] [0054 ]FIG. 3 is an illustration for showing the torque applied to the valve shaft 108 of the throttle valve 102 by the default mechanism using the return spring 111 and the default spring 112 .", "The preload is applied to both the return spring 111 and the default spring 112 in advance.", "The optimal value therefore exists for each preload.", "If the preload is too large, it causes a long response time in the opening and closing operations of the throttle valve 102 , and if the preload is too small, the throttle valve 102 cannot return to the default position, which is due to air resistance and friction in the rotation.", "The preload of the return spring 111 is important for reliably returning the throttle valve 102 to the default position, and the force of 30-40 kgfmm is necessary for the preload.", "[0055] In the following, the operations of the electric-control-type throttle valve will be explained.", "[0056] When torque larger than the spring force of the default mechanism is applied to the valve shaft 108 by the motor 107 , the motor shaft 105 rotates, and the motor gear 106 and the large intermediate gear 104 a also rotate according to the rotation of the motor shaft 105 .", "Because the number of teeth on the motor gear 106 is less than that on the large intermediate gear 104 a, the rotation speed of the motor 107 is reduced.", "The small intermediate gear 104 b rotates together with the large intermediate gear 104 a, and transmits the torque to the valve gear 103 .", "Moreover, because the pitch circle diameter of the small intermediate gear 104 b is set smaller than that of the valve gear 103 , the rotation speed is further reduced.", "Thus, the rotation speed of the motor 107 is reduced by two steps, and is transmitted to the valve shaft 108 .", "[0057] [0057 ]FIG. 6 shows an example of the composition of a direct-injection engine using the electric-control-type throttle apparatus of the present invention.", "The electric-control-type throttle apparatus 61 is arranged at the upper stream side of a direct-injection engine 62 , in an air intake tube 67 .", "A control unit 63 for sending control signals to the motor 107 and driving the motor 107 is connected to the electric-control-type throttle apparatus 61 via a throttle harness 66 .", "[0058] The control unit 63 receives information from the engine 62 via an engine harness 64 , and from other parts of the vehicle via a harness 65 , and determines the target position of the throttle valve 102 .", "Moreover, the control unit 63 receives a position signal detected by the throttle position sensor 110 for detecting the position of the throttle valve 102 , and controls the position of the throttle valve 102 so as to follow the determined target position.", "[0059] A drive circuit 68 for adjusting the power fed to the motor 107 is incorporated in the control unit 63 ,.", "The drive circuit 8 uses the PWM method for controlling the torque generated by the motor 107 by feeding voltage pulses of the variable width to the motor 107 .", "Transistors or FETs (Field Effect Transistor) are used as switching elements to generate the voltage pulses, and the permitted current is assigned to those transistors.", "If a current larger than the permitted current flows in those switching elements of the transistors or FETs, the transistors possibly break down.", "[0060] In Table 1, specification parameters of the motor 107 and the gear ratio of the speed reducing mechanism in this embodiment are shown.", "By using the specification parameters shown in Table 1, it is possible to ensure that the response time of the electronic throttle apparatus is reduced and the overcurrent flowing in the drive circuit is also prevented.", "TABLE 1 20° C. 120° C. −30° C. Torque constant kgfmm/A 3.54 3.07 3.76 Nm/A 0.0347 0.0301 0.0368 Counter- V/krpm 3.65 3.18 3.92 electromotive force Motor impedance Ω 1.61 2.24 1.29 Preload of kgfmm 36 36 36 return spring Nm 0.353 0.353 0.353 Speed-reducing ratio — 10.27 10.27 10.27 [0061] These specification parameters are explained below.", "[0062] When the voltage is applied to a motor 107 , and the motor 107 begins to rotate, the motor 107 generates the induced voltage in the direction opposite that of the applied voltage, which is due to the power generating function which the motor 107 possesses.", "This induced voltage is called the counter-electromotive force, and is proportional to the rotation speed of the motor.", "Because the motor 107 used in the electric-control-type throttle apparatus is controlled so that the position of the throttle valve follows the target position, when the position approaches the target position, voltage is applied to the motor 107 to generate torque for the reverse rotation of the motor 107 so as to reduce the rotation speed of the motor 107 .", "In this operation of the motor 107 , the counter-electromotive force is further added to the applied voltage, and the overcurrent flow may occur in the drive circuit of the motor 107 .", "[0063] For example, FIG. 14 shows the induced counter-electromotive force and the current flow in the motor 107 used in the electric-control-type throttle apparatus.", "[0064] In FIGS. 9A and 9B respectively, a schematic diagram of the composition of the drive circuit 68 , and an example of the voltage pulse pattern applied to the switching elements are shown.", "Moreover, FIG. 10 shows the voltage generated at the motor 107 and the current flow in the switching elements of the drive circuit when the voltage is applied to the motor 107 to generate torque for the reverse rotation of the motor 107 .", "M 1 , M 2 , M 3 , and M 4 indicate the switching elements using FETS, and turn current fed to the motor 107 on or off.", "By turning on M 1 and M 4 (M 2 and M 3 being turned off), the motor 107 is rotated in the forward (valve opening) direction.", "On the other hand, in turning on M 2 and M 3 (M 1 and M 4 being turned off), the motor 107 is rotated in the reverse valve closing) direction.", "When the motor 107 rotates in the reverse direction, the counter-electromotive force of the motor 107 is generated in the direction in which the side A of the motor 107 is positive.", "In order to rapidly decelerate the reverse rotation speed of motor 107 , the voltage in the forward direction is applied to the motor 107 by turning on M 1 and M 4 as shown in FIG. 10.", "Consequently, the direction of the generated counter-electromotive force V m coincides with that of the applied voltage V b (E), and the current i m flows in M 1 and M 4 .", "The flowing current is larger by the amount of the current generated by the counter-electromotive force V m than the current generated by only the applied voltage V b .", "If the current i m exceeds the permitted value of the switching elements M 1 , M 2 , M 3 , and M 4 that is, the current i m is overcurrent, and the switching elements M 1 and M 4 possibly break down.", "[0065] In this embodiment, by adequately setting the impedance of the motor 107 , overcurrent flow in the drive circuit 68 and the motor 107 due to the counter-electromotive force can be prevented.", "[0066] The impedance of the motor 107 is determined so as to satisfy the above-described inequality (2).", "The inequality (2) is again described below.", "R m >", "( E + K e  θ .", "m ) I lim , ( 2 ) [0067] where θ m =ι v ·N, and V m =K e θ m , and R m is the motor impedance [Ω], E: the voltage applied to the motor 107 [V], K e : the induction voltage constant [V/rpm], θ m : the rotation speed of the motor 107 [rpm], θ v : the rotation speed of the throttle valve 102 [rpm], N: the speed-reducing ratio, and V m the counter-electromotive force induced in the motor 107 .", "[0068] The right-hand side of the inequality (2) expresses the resistance obtained by dividing the sum of the applied voltage V b and the counter-electromotive force V m by the permitted current I lim .", "[0069] This impedance R m .", "is the impedance between A and B shown in FIG. 9A, that is, both terminals of the motor 107 , including not only the armature impedance of the motor 107 , but also the impedance of a choke coil used as a noise filter and the brush resistance.", "[0070] Furthermore, the resistance component of the impedance is obtained by measuring current flowing in the motor 107 when the voltage (13 V in this embodiment) is applied and the motor 107 has stalled.", "Hereafter, concerning the impedance of the motor 107 , the resistance component is mainly considered (R m is described as the resistance ).", "[0071] If the resistance R m does not satisfy the inequality (2), the resistance R m is an insufficient value, and the current flowing in the drive circuit 68 may exceed its permitted value.", "In determining the adequate value of the resistance R m , the right-hand side of the inequality (2) is conservatively estimated at the temperature of −30° C. at which the resistance R m has the minimal value in the assumed temperature range of the vehicle operation.", "That is, the right-hand side of the inequality (2) is estimated by using parameters expressing the characteristics of the motor 107 at the temperature −30° C. The rotation speed θ v is defined as the speed 187.5 rpm in rotating the throttle valve from 0 degree to 90 degree (π/2) by 80 ms.", "[0072] Furthermore, in this embodiment, the gear ratio N is 10.28, and the induction voltage constant K e is 3.92 V/krpm.", "The applied voltage E is almost 13 V, which is generated by a battery ordinarily used in a vehicle.", "Although the voltage of the battery is controlled so as to be in the range of 12.7-12.8 V, sometimes the power decreases below 10 V a vehicle is started, or in the dissipated state of the battery.", "Moreover, the voltage of the battery sometimes increases to over 16 V due to the malfunction of a battery voltage control apparatus.", "However, in estimating the right-hand side of the inequality (2), the voltage 13 V usually used in an engine of a vehicle is used.", "Also, as the permitted current of the switching elements in the drive circuit 68 of the motor 107 , 20 A is used.", "By substituting the above values into the right-hand side of the inequality (2), it is found that the resistance R m of more than 1.03 Ω satisfies the inequality (2).", "Furthermore, because it can occur by an error in production that the resistance R m takes a 5% lower value, and the induction voltage constant K e takes a 10% higher value than the nominal value, the right-hand side of the inequality (2) is estimated taking the above error into account.", "Thus, by using the increased value 4.31 V/krpm for the induction voltage constant K e, the resistance R m is estimated as a value higher than 1.12 Ω.", "Thus, in this embodiment, the resistance R m is conservatively set as 1.3 Ω.", "[0073] In the above-mentioned example, the operation time in which the throttle valve 102 is driven from the minimum opening to the maximum opening is set as 80 ms.", "In order to determine the resistance R m more precisely, the following method can be used.", "That is, the operation time t of the throttle valve 102 is obtained by using the above-described equation (1) (as the parameters expressing the characteristics of the motor 107 , their values at not 120° C. but −30° C. are used), and the resistance R m can be also determined with the rotation speed θ v of the valve 102 calculated by using the above-obtained operation time t. By using this method of determining the resistance R m , the breakdown of the switching elements in a drive circuit can be prevented even in an electric-control-type throttle apparatus in which the operation time t is much shorter than 80 ms.", "However, in the above method, because the parameters of the motor at −30° C. are used, it may occur that the determined resistance R m is too large at the operating temperature, which in turn decreases the current flowing in the motor 107 too much, and the output torque of the motor 107 becomes insufficient.", "Consequently, the response of the electric-control-type throttle apparatus deteriorates.", "Moreover, the delay effect of a control system is not considered in the equation (1).", "If the very quick response of the electric-control-type apparatus is intended, this delay effect cannot be neglected.", "[0074] Accordingly, it is more appropriate that the necessary resistance R m at 20° C. is determined with the inequality (2) by using the operation time t of the valve 102 , which is obtained by using the equation (1) in which the parameters expressing the characteristics of the motor 107 at 20° C. are used.", "As for the operation time t of 40 ms (375 rpm), it is seen in FIG. 5A that the adequate gear ratio N is about 10 at 20° C. Consequently, the resistance R m at 20° C., satisfying the inequality (2), is estimated as more than 1.35 Ω.", "Furthermore, by taking the error of the quantity production into account, it is preferable to set the resistance as more than 1.49 Ω.", "In this embodiment, the resistance R m at 20° C. is more conservatively set at 1.61 Ω.", "[0075] According to the above method of determining the resistance R m , the current flowing in the motor 107 and its drive circuit 68 is restricted so as not to exceed the permitted value, and it is possible to reduce the probability of the breakdown of the switching elements in the drive circuit 68 without using a complicated circuit or control method.", "[0076] Other methods in which the value of the right-hand side of the inequality (2) is always monitored and the applied voltage is controlled so as to satisfy the inequality (2) are also effective in preventing the breakdown of the switching elements.", "A system for implementing the above method is shown in FIG. 6. In one of the above methods, a control circuit 63 calculates the rotation speed of the motor 107 based on the change rate in time of the target opening, and monitors and predicts the value of the right-hand side of the inequality (2).", "Moreover, it controls the voltage applied to the motor 107 so as to satisfy the inequality (2).", "If the rotation speed of the motor 107 is high and the value of the right-hand side of the inequality (2) is predicted to exceed the value satisfying the inequality (2), the sum of the applied voltage V b (E) and the counter-electromotive force V m is decreased by decreasing the applied voltage, particularly when it begins to apply the reverse voltage to the motor 107 .", "In another one of the above methods, the voltage between the terminals A and B of the motor 107 (counter-electromotive force) is monitored, and the control circuit 63 always calculates the sum of the applied voltage V b (E) and the counter-electromotive force V m .", "Moreover, if the rotation speed of the motor 107 is high and the value of the right-hand side of the inequality (2) is predicted to exceed the value satisfying the inequality (2), the control circuit 63 stops applying the voltage to the motor 107 .", "In another of the above methods, the control circuit 63 always monitors the value obtained by dividing the sum of the applied voltage V b (E) and the counter-electromotive force V m by the resistance R m , and if the value is predicted to exceed the permitted current, the control circuit 63 stops applying voltage to the motor 107 briefly, and then start applying voltage to the motor 107 again.", "[0077] Each of the above-mentioned methods can be implemented by a simple circuit, and because it is not necessary to use a motor of a large resistance R m , the heat (joule heat) generated in the coils of the motor 107 can be reduced.", "Moreover, because it is possible to always flow current at a level near the permitted current, the operation time of a throttle valve 102 can also be reduced.", "[0078] As for the gear ratio, it is set as 10.28 in this embodiment.", "By using this gear ratio, it becomes possible not only to secure the stable response of the electric-control-type throttle apparatus, which is not affected by the dispersion in the characteristics of the motor 107 and the spring force of the default mechanism or by load torque changes due to the deposit on the throttle valve 102 , but also to operate the throttle valve 102 at a relatively high speed.", "[0079] Meanwhile, the gear ratio 10.28 is determined by the tooth numbers of the respective motor gear 106 , large intermediate gear 104 a, small intermediate gear 104 b, and valve gear 103 shown in FIG. 1 and FIG. 8. The respective tooth numbers are 21 , 65 , 22 , and 73 (this value is converted to the all-around tooth number) for motor gear 106 , the large intermediate gear 104 a, the small intermediate gear 104 b, and the valve gear 103 respectively.", "It is not always necessary to use those tooth numbers for implementing the present invention.", "Moreover, the target gear ratio cannot be always precisely realized.", "The reason is that the tooth number of a gear depends on the distance between the shaft of each gear and that of a gear or gear module neighboring the gear, and those distances are also restricted by the size of each gear.", "Therefore, it is practical to set the gear ratio in the range of 9.80 to 10.78, which is determined by taking the variation caused by one tooth in the teeth of each gear into account rather than to set the ratio at one value of 10.28.", "[0080] In the electric-control-type throttle apparatus, if the gear ratio is set low, it is difficult to stably operate the throttle apparatus because the spring force of the default mechanism becomes large relative to the torque of the motor 107 , which makes the change in the operation time sensitive to the change of the torque of the motor 107 .", "Furthermore, the equivalent moment of inertia of the throttle valve 102 to be driven by the motor 107 becomes relatively large, which degrades the response of the throttle apparatus.", "[0081] Conversely, if the gear ratio is set high, it takes more time to accelerate the motor 107 because it is necessary to rotate the motor 107 at a high speed in order to obtain the quick response of the throttle apparatus.", "Thus, the response of the throttle apparatus is deteriorated, which is not preferable for a direct-injection engine.", "[0082] [0082 ]FIG. 11 shows an illustration to explain the motion of the electric-control-type throttle apparatus.", "When the motor 107 generates the torque T m , the gears rotate and reduce the rotation speed that is transmitted from the rotation speed of the motor 107 to the valve shaft 108 by the degree of the ratio N, and rotates the throttle valve 102 to which the spring load T s is applied.", "Equations of motion in a system shown in FIG. 11 are expressed by the following equations (3): J   θ ¨ v + T s = T m  N  To = K m  I L m  I + R m  I + K e  N   θ .", "v = E } , ( 3 ) [0083] where To : the torque of the motor [Nm], K m : the torque constant [Nm/A], I: current flow in the motor [A], and L m : the inductance of the motor [H].", "[0084] The above equations (3) express the mechanical motion, the torque generated in the motor, and the voltage relation, respectively.", "It is seen that smaller values of the moment of inertia J, the inductance L m , the resistance R m , and the preload torque T s of the return spring 111 move the throttle valve more quickly.", "Thus, the values of the torque constant K m , the induction voltage constant K e , and the gear ratio N should be optimized.", "[0085] The gear ratio N used in this embodiment is determined so as to realize the stable and quick operation of the electric-control-type throttle apparatus.", "To determine this gear ratio N, the equation (1) is used.", "The equation (1) is again described below.", "t = π ( T max  N - T s ) J , ( 1 ) [0086] where T max =K m E/R m and T s : the preload of the return spring 111 of the force applying means [Nm], T max : the torque of the motor 107 [Nm], N: the speed-reducing ratio, J:the equivalent moment of inertia [kgm 2 ], K m : the torque constant [Nm/A], R m : the resistance of the motor 107 [Ω], and E: the voltage applied to the motor 107 [V].", "[0087] The equation (1) is obtained by neglecting both the inductance L m that slightly affects the motion of the system, and the transient effects in the motion of the motor 107 , assuming that the torque To approximately reaches the maximum value T max ;", "and by integrating the equations (3).", "Although the equation (1) is an approximate equation which does not include the delay effect of a control system, the response performance of the control system can be designed to be sufficiently quick if a mechanical system can be operated quickly enough.", "Therefore, in this embodiment, the equation (1) expresses a value close to the accurate operation time t of the throttle valve 102 .", "[0088] In estimating the operation time t by using the equation (1), it is assumed that the throttle valve 102 is rotated by the angle π/2 from the minimum opening to the maximum opening.", "Because the torque generated by the motor 107 decreases when the temperature of the motor 107 increases, the values at 120° C. concerning the parameters are used in the right-hand side of the equation (1) by assuming that this electric-control-type throttle apparatus is left in the environment of 120° C. for a long time and that the temperature of the apparatus reaches its equilibrium state.", "As the moment of inertia J, the equivalent moment is used: that is, the moment obtained by combining and converting the moment of inertia of the motor 107 and the moment of inertia of the respective gears into one lump of moment of inertia attached to the valve shaft 108 .", "Also, the value 13 V which is the voltage of an ordinarily used battery is used as the applied voltage, [0089] To realize the high speed operation of the electric-control-type throttle apparatus, it is desirable that the operation time t estimated by the equation (1) is less than 80 ms.", "Because the characteristics of the motor 107 cannot be freely changed, the operation time t is adjusted by changing the gear ratio N, based on the selected specification parameters of the motor 107 .", "In the following, the gear ratio (speed-reducing ratio) will be explained.", "FIG. 5A shows the relationship between the operation time t estimated by using the equation (1) and the gear ratio (speed-reducing ratio).", "From this figure, it is seen that the operation time t gradually changes in the range of the gear ratio N from 2.5 to 32.", "On the other hand, the operation time t rapidly changes below the gear ratio 2.5, and the stable operation of the throttle valve 102 becomes difficult because the spring load of the return spring 111 becomes relatively large.", "In the range of the gear ratio of 2.5 to 5, the change in the operation time t is sensitive to the change in the gear ratio.", "This situation is similar to the change in the load of the motor 102 .", "That is, the operation time t mainly changes relative to small changes in the load.", "Two dotted lines shown in FIG. 5A indicate the best and worst estimated operation times t when the induction voltage constant K e and the resistance R m of the motor at 120° C. change by 10% and 5%,respectively, which are caused by an error in the quantity production.", "From those lines, the change in the operation time t is sensitive also to changes in the characteristic parameters of the motor 107 below the gear ratio 5 .", "[0090] [0090 ]FIG. 5B shows changes in the operation time t corresponding to changes in the temperature at the gear ratios 3 and 10 .", "The gradient of the line at the gear ratio 3 is larger than that at the gear ratio 10 , that is, the change in the operation time t at the gear ratio 10 is less sensitive to a change in the temperature than that at the gear ratio 3 .", "The lower sensitivity to the temperature is more favorable for controlling the throttle apparatus because control becomes easier.", "Therefore, the control performance at the gear ratio 10 is superior to that at the gear ratio 3 .", "The specification parameters which change correspondingly with the change in the temperature are mainly the torque constant and the resistance of the motor 107 .", "Accordingly, if the temperature is high, the torque generated in the motor 107 is small, and vice versa.", "Furthermore, the change in the temperature can be replaced with the change in the torque generated in the motor.", "Consequently, it can be said that, at the small gear ratio, the change in the operation time t is large relative to the change in the torque generated by the motor 107 (the change in the temperature).", "Considering the small gear ration from another view point, because the small gear ratio means that the torque transmitted to the valve shaft 108 of the throttle valve 102 is small, it can be also said that the operation time t becomes sensitive to a change in the load applied to the valve shaft 108 if the gear ratio is small.", "Thus, the large gear ratio brings the stable operation time t, and is advantageous to the control of the electric-control-type throttle apparatus.", "In showing the dependency of the operation time t on the temperature in FIG. 5B, the values 3 and 10 of the gear ratio are selected as typical values.", "The gear ratio 3 is in the region of the negative gradient of lines expressing the dependency of the operation time on the gear ratio shown in FIG. 5A, and the gear ratio 10 is in the region of the positive gradient of those lines shown in FIG. 5A.", "As shown by the line at the gear ratio 3 in FIG. 5B, the tendency in which the operation time t largely changes along with the change in the temperature occurs in the negative region of those lines shown in FIG. 5A.", "Therefore, in determining the gear ratio, it is desirable to select the gear ratio in the region of the positive gradient of those lines in FIG. 5A, in which the operation time t is comparatively insensitive to the change in the temperature (namely, torque and load).", "[0091] In this embodiment, the gear ratio is determined within the range of the positive gradient of those lines shown in FIG. 5A.", "It is because, as mentioned above, the change in the operation time t is small relative to the change in the load or the change in the characteristics of the motor 107 in this region of the gear ratio and the stable operation of the throttle valve 102 can be maintained.", "[0092] By selecting the above-mentioned gear ratio, when the electric-control-type throttle valve of the present invention is applied to a direct-injection engine, it is possible to realize a quick response with only minimal changes in the output power of the engine even when switching the burning mode.", "[0093] In FIG. 7, output power changes in a direct-injection engine, which occur when switching the burning mode, are shown with respect to the operation time t. From this figure, it is seen that the output power changes when switching the burning mode are comparatively low in the range below the operation time of 80 ms.", "The reason will be explained in the following.", "[0094] The electric-control-type throttle apparatus 61 of this embodiment is arranged in the upper stream of the air intake pipe of the engine 62 as shown in FIG. 6. Therefore, even if the throttle valve 102 is driven rapidly, the actual flow rate of the intake air into the engine 62 is delayed by the volume of a manifold part from the exit of this throttle apparatus 61 to the entrance of the engine 62 .", "Thus, even if the throttle valve 102 is instantaneously driven from the fully open state to the fully closed state within, for example, 10 ms, the flow rate of the intake air into the engine 62 does not instantaneously become 0, but gradually decreases to 0.", "In FIG. 13, the change in the flow rate of the intake air in instantaneously opening the throttle valve 102 from the fully closed state to the fully open state is shown until the flow rate reaches the rated value 100%.", "The delay time τ depends on the ratio of the volume of the manifold part of the air intake pipe to the engine swept volume and the rotation speed N e of the engine 62 , and this delay time τ is obtained by the following equation (4): τ=120·V man /(V d ·N e ) (4), [0095] where V man : the volume of the manifold part from the exit of this throttle apparatus 61 to the entrance of the engine 62 [L], V d : the engine swept volume [L], and N e : the rotation speed of the engine 62 .", "[0096] The ratio of the V m /V d is generally about 0.8-1.5.", "The delay time τ is defined as the time at which the flow rate reaches the value of 63% of the rated flow rate, and the response time at which the flow rate effectively reaches 100% is defined as the time at which the dotted line connecting the original point and the point of 63% intersects the horizontal line of 100% in FIG. 13.", "The response times are calculated by varying the ratio V m /V d and the rotation speed N e .", "Results of the calculation are summarized in Table 2.", "[0097] Switching the burning mode in a direct-injection engine is carried out within the range of 2000 rpm to 3000 rpm.", "In this range, the minimum response time necessary for the flow rate to reach time under the conditions of Ne: 3000 rpm and the ratio V m /V d : 0.8 is 51 ms, and the maximum response time under the conditions of Ne: 2000 rpm and the ratio V m /V d : 1.5 is 143 ms.", "TABLE 2 Rotation The ratio of the air intake pipe volume to the speed N e of engine swept volume [V man /V d ] engine [rpm] 0.8 1.0 1.2 1.5 1000 0.152* 0.190 0.229 0.286 1500 0.102 0.127 0.152 0.190 2000 0.076 0.095 0.114 0.143 2500 0.061 0.076 0.091 0.114 3000 0.051 0.063 0.076 0.095 4000 0.038 0.048 0.057 0.071 5000 0.030 0.038 0.046 0.057 [0098] However, it is rare for the burning mode to be switched near the rotation speed 3000 rpm, and the ratio V m /V d is usually more than 1.0.", "Therefore, the operation time of the throttle valve 102 is preferably set less than 100 m when applying the throttle apparatus to a direct-injection engine in which the burning mode is switched near the rotation speed 2000 rpm.", "If the throttle apparatus can realize the operation time t of less than 80 ms, it can be applied to almost all direct-injection engine.", "In this embodiment, the ratio V m /V d is about 1.0, and the rotation speed when switching the burning mode is about 2500 rpm.", "By using the electric-control-type throttle apparatus, the operation time of 80 ms is almost equal to the response time of the flow rate in the lower stream region (manifold part) of the air intake pipe.", "Thus, because the flow rate of the intake air into the engine 62 can be controlled at a high speed, the change in the output power of the engine 62 can be reduced as shown in FIG. 7. [0099] Furthermore, in the electric-control-type throttle valve, it is a characteristic particular to this type of throttle apparatus that the throttle valve must be released from its sticking state due to the soil deposit caused by the adhesion of gum-state substances.", "Especially in this embodiment which does not use the pedal operation transmission mechanism in which the throttle valve 102 is directly driven by a wire connected to the acceleration pedal operated by a driver, the sticking state of the throttle valve 102 must be released by only the torque of the motor 107 .", "Although the sticking force varies depending on the operation environment of the throttle valve 102 , if the torque of more than 110 kgfmm can be applied to the shaft of the throttle valve 102 , this torque is sufficient to release almost all of the assumed sticking states.", "[0100] The excess quantity of the torque which can be applied to the valve shaft 108 beyond the preload torque of the return spring 111 at the default position of the throttle valve 102 is called the sticking release torque.", "That is, the sicking release torque is the difference between the torque applied to the valve shaft 108 by the motor 107 and the preload torque of the return spring 111 .", "The gum-state substances causing the sticking state of the throttle valve 102 are softened at a high temperature.", "On the other hand, because the maximum torque generated by the motor 107 increases when the temperature decreases, it is appropriate to estimate the sticking release torque at the ordinary temperature (20° C).", "Moreover, it is assumed that the sticking of the throttle valve 102 occurs during a long-term stoppage of the vehicle, for example, parking for a long time, which possibly causes the decrease of the voltage V b of the battery.", "Therefore, as the voltage V b of the battery, the value of 10 V is used to conservatively estimate the sticking release torque brought by the motor 107 .", "In this embodiment, the maximum torque generated by the motor 107 is 21.9 kgfmm at the applied voltage E of 10 V, the gear ratio N is 10.3, and the preload torque of the return spring 111 is 36 kgfmm.", "Therefore, the sticking release torque (190 kgfmm) applied to the valve shaft 108 is larger by about 80 kgfmm than the necessary sticking release torque 110 kgfmm.", "Therefore, the sticking release torque is sufficiently secured in this embodiment, and the electric-control-type throttle apparatus of this embodiment is powerful against the sticking of the throttle valve 102 , which improves the reliability the throttle apparatus.", "[0101] [0101 ]FIG. 15 shows the relationship between the limit values of the motor resistance R m and the values of the torque constant K m under the conditions of each value at the operation time of 80 ms, the necessary sticking release torque of 110 kgfmm, and the permitted current of 20 A. The equivalent moment of inertia J is set as 0.0013 kgm 2 .", "[0102] In FIG. 15, the solid line A indicates the upper limit values of the motor resistance R m such that the operation time of the throttle valve 102 is less than 80 ms.", "It is desirable to set the torque constant K m and the motor resistance R m as values in the lower side region of the line A. The solid line C indicates the lower limit values of the motor resistance R m such that the peak current flow in the motor 107 is less than the permitted current 20 A. Accordingly, it is desirable to set the torque constant K m and the motor resistance R m as values in the upper side region of the line C. Consequently, it is desirable to set the torque constant K m and the motor resistance R m as values in the region between the lines A and C. As to the torque constant K m , because the electromagnetic force of the motor 107 should be increased to satisfy the value of greater than 0.04 Nm/A, which increases its production cost and its size, the value of less than 0.04 Nm/A is desirable although it is possible to set the torque constant K m to a value of more than 0.04 Nm/A .", "On the other hand, if the torque constant K m is less than 0.025 Nm/A, it is necessary to have a large current flow in the motor 107 , and the influence of the production error of the motor resistance R m becomes relatively large.", "Therefore, the region surrounded by a pair of dotted lines and the line A and C is a desirable region to set the torque constant K m and the motor resistance R m .", "[0103] Furthermore, the upper limit values of the motor resistance R m such that the sticking release torque is more than 110 kgfmm are indicated by the line B in FIG. 15.", "In order to secure a sticking release torque of more than 110 kgfmm, it is necessary to set the torque constant K m and the motor resistance R m in the lower region of the line B. Thus, the shadowed region surrounded by a pair of dotted lines and the line A and C becomes a more appropriate region to set the torque constant K m and the motor resistance R m .", "In this embodiment, taking the error in the production into account, the torque constant K m and the motor resistance R m are set within 0.03-0.037 Nm/A and within 1.29-2.24 Ω, respectively.", "[0104] As a typical example of the specification parameters for the electric-control-type throttle apparatus, in this embodiment, the following values are set: that is, the torque constant K m of 0.035±0.0035 Nm/A, the motor resistance R m of 1.61±0.08 Ω, and the speed-reducing ratio N of 10.3 (9.8-10.8).", "Moreover, by setting the preload torque of the return spring 111 at 0.35 (0.3-0.4) Nm, the operational safety of the vehicle to which the electric-control-type throttle valve of the present invention is applied is secured because the position of the throttle valve 102 is automatically returned to the predetermined opening position even if the motor 107 fails.", "[0105] By using the electric-control-type throttle apparatus of the present invention, it is possible to operate the throttle valve 102 at a high speed, which can reduce the change in the output power of the engine 62 even when switching the burning mode from the stratified charge burning mode to the uniform mixture charge burning mode in the direct-injection engine.", "Furthermore, it is possible to prevent the overcurrent flow in the drive circuit 68 when operating the throttle valve 102 at a high speed that is, the burning of the switching elements in the drive circuit 68 can be prevented, which improves the fail-safe performance of the throttle apparatus.", "[0106] Although the voltage 13 V is used as the applied voltage E in the above embodiments, other values of the applied voltage E are applicable." ]
BACKGROUND OF THE INVENTION The disclosed invention is related to graphics display technology, and more specifically to methods for blending colors in a graphics processing unit. Color blending is a process which combines color channels and alpha channels from sources of image information in order to generate modified image information. One such method has been described by Thomas Porter and Tom Duff in “Compositing Digital Images”, Computer Graphics, 18(3), July 1984, 253-259. Blending is required in systems like computer-generated graphics, image fusion for visualisation, graphical user interfaces etc. and is usually part of a Graphics Processing Unit (GPU), i.e. of a device that can render graphic images to be displayed on computer screens. Image blending was used from the start of motion picture generations (U.S. Pat. No. 1,262,954). Blending was part of computer-based image processing since its origins (U.S. Pat. Nos. 4,384,338, 4,679,040, 4,827,344). Original blender implementations were based on image multiplexing at the output to a screen via analog circuitry or on software programmes running on standard processors. This method is suitable for applications where high-speed software processing resources are available or where there is no high-speed requirement for the generation of the output images, as is the case with photograph editing. In order to be able to process blending in real time systems, a hardware blender is required. Methods that implement blending in hardware have been proposed as described in the following paragraphs: One of the first architectures of a blending apparatus was suggested in U.S. Pat. No. 5,592,196. This apparatus includes instructions for implementing the blending functions. These instructions are included in tables which form a blending mode, making the method fast but not as flexible as a full programmable approach. A hardware implementation of blending targeted explicitly to 3D graphics has been disclosed in U.S. Pat. No. 5,754,185. This method did not include any programmability mechanism but rather defined blending mode via control signals. Another hardware implementation is described in U.S. Pat. No. 5,896,136. This description mentions a unit that implements blending equations by using an alpha channel of lower resolution than the RGB channels. In a structure described in U.S. Pat. No. 7,397,479 a method for providing programmable combination of pixel characteristics is disclosed. Methods for implementing programmable blending were disclosed with patent application US 2006/192788 and U.S. Pat. No. 7,973,797. In both cases, the instructions for blending are provided by a processing unit loading formula or operation descriptors as a sequence to be executed by the blending hardware. Blending in the above referenced cases is defined as the process of generating a target pixel fragment value (T) by combining various inputs: a said source pixel fragment (S), a said destination pixel fragment (D) and corresponding alpha values (A s , A d ) for the source and destination pixels. Depending on the blending mode a different function (f) is applied in order to calculate the target. For calculating the target (T=f(S, A s , D, A d )), an arithmetic and logical unit (ALU) is employed that uses the said inputs and the blending mode in order to produce the target value. For many blending modes, computing the formula in a single operation requires complex hardware. In order to minimize hardware using simpler operators, the outputs can re-enter the ALU a second time or more until the formula is calculated. During this iterative process the blender cannot receive new inputs, thus complex blending modes result in lower overall throughput of the GPU. One method to achieve higher throughput is to implement the ALU as a pipeline of at least two threads. If the input pixel fragments can be provided in a continuous flow, the pipeline can produce one output per each clock cycle. The current state of the art in color blending devices as described above provides fast and programmable functionality. Many different operations—from a predefined set—can be performed on sequences of pixel fragments, where each pixel is represented as a color (c, usually R,G,B) and alpha (α) combination. One shortcoming of current implementations is that they are best fit for systems where the locations of subsequent pixel fragments are more or less continuous. In a modern GPU system like the one shown in FIG. 2 , Shader 206 processing and communication to the main memory for reading and writing pixel fragments is a bottleneck. Thus, the system cannot generate a steady flow of continuous pixel fragments. Another limitation is that most current implementations operate on integer or fixed-point representations. This makes it harder to interface with floating-point pixel sources and frame buffers. Furthermore, this limits the dynamic range of color representation for each pixel fragment. Another limitation of most current solutions is that the programmability is constrained by a few predefined operators. In one case only (U.S. Pat. No. 7,973,797), the operation is guided by two instructions which can be configured by other entities in the GPU. A more flexible approach is required for full programmability, where any sequence of instructions including flow control can be provided as input in the form of a small program for the blender core. All existing implementations support the RGBA color scheme that is very common in computer graphics; each pixel fragment is represented by three color channels of Red, Green and Blue (RGB) and an Alpha channel (A). However, if one has to blend non-RGBA pixel fragments (for example pixels in YUVA representation commonly used in video and photography), there needs to be another step of color space conversion, consuming time and bandwidth. SUMMARY OF THE INVENTION The disclosed apparatus provides color blending functionality with fully programmable sequences of operations on the source and destination pixel fragments. The architecture of the device is based on the observation that modern graphics systems do not generate steady flow of pixel fragments, leaving the blender with unused processing capability. The disclosed blender takes advantage of this fact in order to multiplex in time many blending functions on different fragments of pixels. This is achieved by the multithreading capability of the blender core. The disclosed device is a blender which is build around arithmetic and logic units (ALUs) that implement a plurality of blending functions as defined by a sequence of instructions. The core of the said blender is capable of pipelining the instructions in order to achieve high throughput of results. Furthermore, the said blending core can handle instructions from a plurality of sequences and operate on a plurality of input streams. This feature of the said blending core provides for multithreaded operations, thus minimizing the time a blender has to wait for non-continuous pixel fragments to be fetched from a memory. The disclosed blending device consists of (a) circuitry that reads, reformats and aligns pixel fragments from two inputs, (b) a blending core that can execute threads of instruction sequences in order to generate a result and (c) an output selection and reformatting circuitry that produces the final output pixel fragments. In one embodiment, the disclosed apparatus will be able to run the following operations: Blending of source & destination pixel fragments according to alpha values and a chosen mode. Concurrent multithreaded processing of a plurality of pixel fragments with different blending functions applied to each pixel fragment. Implementation of a wide variety of blending modes including the ones defined in the Khronos group standards OpenGL and OpenVG, regardless if the input or output streams are premultiplied or non-premultiplied. Conversion from RGB to YUV color space and vice versa. Gamma/degamma color correction. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a typical minimal embedded system-on-chip with a graphics processing unit. FIG. 2 shows a top level block diagram of a graphical processing unit (GPU) that is implemented using the disclosed blending device. FIG. 3 shows a possible structure of the disclosed blending device. FIG. 4 contains a block diagram of a possible embodiment of the core multi-threaded blender. FIG. 5 shows the internal structure of the ALU blocks of FIG. 4 . FIG. 6 presents the structure of a possible embodiment of an operations pipeline. FIG. 7 presents some blending mode examples. FIG. 8 shows a possible structure for the instructions used by the blender. DETAILED DESCRIPTION OF THE INVENTION Usage Graphics Processing Units (GPUs) are increasingly required to perform a plurality of blending functions. When projecting glyphs or user interface items like icons, buttons or window frames over an image, or when combining images from different sources, or when drawing a 3D scene with items on the foreground and items on the background, or when translucent items are displayed, in all those cases a target pixel value on the display is the result of the combination of two input pixel fragments weighted by a value called the alpha of that pixel fragment. Some examples of blending modes are described in table 1, which are defined in the Qt application framework: TABLE 1 Blending mode examples Name Description Source Over/ The alpha of the source is used to blend the pixel on top of the Destination Over destination. Destination Over is the inverse of Source Over. Clear The pixels in the destination are cleared (set to fully transparent) independent of the source. Source/ The output is the source/destination pixel. Destination Source In/ The output is the source, where the alpha is reduced by that of Destination In the destination. Destination In is the inverse of Source In. Source Out/ The output is the source, where alpha is reduced by the inverse Destination Out of destination. Destination Out is the inverse of Source Out. Source Atop/ The source pixel is blended on top of the destination, with the Destination Atop alpha of the source pixel reduced by the alpha of the destination pixel. Destination Atop is the inverse of Source Atop. Xor The source, whose alpha is reduced with the inverse of the destination alpha, is merged with the destination, whose alpha is reduced by the inverse of the source alpha. Plus Both the alpha and color of the source and destination pixels are added together. Multiply The output is the source color multiplied by the destination.. Screen The source and destination colors are inverted and then multiplied. Overlay Multiplies or screens the colors depending on the destination color. The destination color is mixed with the source color to reflect the lightness or darkness of the destination. Darken The darker of the source and destination colors is selected. Lighten The lighter of the source and destination colors is selected. Color Dodge The destination color is brightened to reflect the source color. A black source color leaves the destination color unchanged. Color Burn The destination color is darkened to reflect the source color. A white source color leaves the destination color unchanged. Hard Light Multiplies or screens the colors depending on the source color. A light source color will lighten the destination color, whereas a dark source color will darken the destination color. Soft Light Darkens or lightens the colors depending on the source color. Similar to HardLight. Difference Subtracts the darker of the colors from the lighter. Painting with white inverts the destination color, whereas painting with black leaves the destination color unchanged. Exclusion Similar to Difference, but with a lower contrast. Painting with white inverts the destination color, whereas painting with black leaves the destination color unchanged. Source Or/And/ Does a bitwise OR/AND/XOR operation on the source and Xor Destination destination pixels (src OR dst). Not Source And Does a bitwise NOR operation on the source and destination Not Destination pixels ((NOT src) AND (NOT dst)). Other similar modes are also defined: ((NOT src) OR (NOT dst)), ((NOT src) XOR dst), (NOT src), ((NOT src) AND dst), (src AND (NOT dst)). The example diagram of FIG. 1 shows a typical system that performs graphics processing. The system connects all devices through a Bus Fabric 110 and is controlled by a Central Processing Unit (CPU) 102 . Graphics and Imaging functionality is performed in a Graphics Processing Unit (GPU) 200 . The program for the CPU and the GPU as well as the images handled by them are stored in a Memory 104 . The display of the system is updated through a Display Controller 106 . In one embodiment of the disclosed invention, the GPU and the display controller are connected through a direct link 108 for frame synchronization and bandwidth shaping. An abstract diagram of the GPU 200 from FIG. 1 is given in FIG. 2 . Connections to the CPU 212 and the Memory 214 are shown as direct links for simplicity, although they are typically implemented through a bus fabric. A Primitive Generator 204 block is used to create vectors, polygons, triangles, curves etc. as described in documents like U.S. Pat. No. 5,303,321. The core of the GPU is a processing unit, the Shader 206 , which calculates graphics functions in order to determine pixel fragment color and transparency values. One or more of said Shaders can exist in a GPU, each one dealing in parallel to the others with separate primitives or fragments. The output of the said Shader can be processed by units 208 that accelerate the generation of texture elements. Pixel fragments from the Shader are provided as input to a Blender 300 , which implements color/alpha blending. The Blender interfaces with the memory 214 for reading background image fragments and in order to store the blended output. Structure The disclosed apparatus is hereby described by reference to the block diagram of FIG. 3 . This block diagram shows the units that constitute the said blending device ( 300 in FIG. 2 ). The block diagram also shows connections between the units. The disclosed blending device operates on input streams of pixel fragments. One input is the stream of source fragments 302 which is typically provided by a Shader. If the blending mode requires that the output solely depends on the said incoming fragments, then the data simply enters the Source Reformat and clamping circuit 308 . If the decision is made 304 that a Destination Fragment is also required, then a request to the memory is issued 318 , and the operation waits until the said destination fragment is received 320 , and reformatted and clamped 306 . The two input streams come from different sources and need alignment 310 in order to be processed while maintaining spatial coherency. Processing is performed by the core 400 of the said blending device. The output of the core may have to be reformatted 312 if the target frame buffer uses a different pixel format. The same block 312 also performs color dithering in order to enhance the visual experience. When multiple outputs are generated, other circuitry 314 re-orders and aligns the pixel data so that they can be stored in the memory's frame buffer 316 . The core of the disclosed blending device is a Blender Core 400 which is multi-threaded. By allocating processing resources to more than one thread of execution, the blender core can multiplex in time a number of parallel blending operations, hiding the latency of arithmetic units, hiding the latency of reading fragments and sustaining throughput. FIG. 4 shows a possible embodiment of the said multi-threaded blender core. A brief description of the structure follows. The said blender core reads two aligned and appropriately preformatted pixel fragments, the source 404 and the destination 402 , consisting of color and alpha information for each input including possible stencil information in the alpha channel. The two inputs are maintained 406 until a processing slot in the arithmetic logic units becomes available. There are two arithmetic logic units ALUs, one for performing operations with the Alpha channel 430 and one for performing SIMD operations with the color channels 420 . The ALUs perform operations by reading a sequence of instructions from the Instruction Memory Contexts 410 . Multiple contexts exist in order to support multithreading. Each instruction sequence forms a small program that is executed by the disclosed blender core utilizing the operators in the said ALUs. The ALUs can also employ temporary data storage and look-up tables 408 to perform certain operations. The results from the blender core ALUs are selected 412 as defined in the instructions by the output circuitry and appropriately converted 414 to a suitable output pixel format, for example floating point (GL_RGBA32F, GL_RGBA16F), fixed point, RGB888, RGB565 etc. The output from the said blender core can be stalled based on a signal 108 from the display controller 106 , indicating high risk of data starvation which might lead to loss of visible frames. The internal structure of the ALUs of the disclosed blander core is shown in FIG. 5 . As stated, the inputs are pixel fragments formatted for blending. One is the source pixel fragment that consists of source color 502 and source alpha 504 . The second is the destination pixel fragment which consists of destination color 506 and destination alpha 508 . The output is a pixel fragment represented by its color channels 516 and its alpha 518 . The color ALU 420 in the diagram contains three parallel operation pipeline blocks 522 , 524 , 526 so that it can support up to three color channels. Other embodiments with less or more color channels are also possible. The output of each operation pipeline block can be fed back 510 to the ALU for a subsequent processing step or can be forwarded to one of a multitude of intermediate registers 528 , 529 . The Alpha ALU 430 contains one operation pipeline block 432 similar to the said operation pipeline blocks of the color ALU. The result is stored in a couple of intermediate registers 538 , 539 or fed back 510 to the inputs of the ALUs for the next step in the blending sequence. The output of the said color ALU is generated by combining or selecting 512 from the said two or more intermediate registers 528 , 529 and storing the result in the target pixel color 516 . The output of the said alpha ALU is generated by combining or selecting 514 from the said two intermediate registers 538 , 539 and storing the result in the target pixel alpha 518 . The detail of each ALU operation pipeline block is shown in a possible embodiment in FIG. 6 . The instructions are fetched for multiple threads from the instruction memory contexts 410 . A dedicated fetch logic circuitry 418 chooses one instruction from each active thread per clock and feeds them 660 to the internal pipeline stages of the ALU operation. The figure shows an example with four threads A, B, C and D. The first instruction from each thread —instr0— is already in the pipeline, the second instruction from each thread —instr1— is ready to be executed, and the following instructions—inst2, instr3, instr4—wait in the memory contexts. The first stage is instruction decode 622 which determines the type of instruction and the corresponding operator 632 that must be used. It is possible that the instruction op-code affects directly the next instruction that needs to be fetched, thus executing a non-conditional branch. This branch request 642 is reported to the instruction fetch logic 418 . Data are fetched 624 at the same clock cycle with instruction decode from the input port 610 of the ALU which can be connected to a previous output of the same or another ALU operations pipeline or to a temporary location in memory or to a look-up table. Fetched data are fed to the next pipeline stage via registers 634 . The core operators of each currently processed instruction are in the subsequent pipeline stages 626 , 628 , 630 . Operators include multiplication, addition, subtraction, logical operators, reciprocal and floor/ceiling. The result is stored in pipeline registers 636 , 638 , 640 and the flags 644 generated by the operation are reported to the instruction fetch logic. The described embodiment uses three pipeline stages for the operators; alternative implementations can include more or less stages to achieve an optimum trade-off between complexity, throughput, latency and number of threads that can be supported. The output from the last stage of the pipeline 640 is directly placed on the port of the ALU operations pipeline 650 . Depending on the op-code, the output can be fed back for a next instruction through the ALU or placed on the output register if processing of the specific data has finished. A possible embodiment of the disclosed invention will include an instruction code structured as: [OC: Op-code][DS: Destination][(S1: Source of input A][S2: Source of input B] and four or more such instructions will constitute a very long instruction word (VLIW) instruction for the entire blending core. This is further illustrated in FIG. 8 . The entire VLIW instruction 820 that goes through the operating units consists of three or more instructions for the color channel pipelines and one instruction for the alpha pipeline. In each VLIW instruction, operations for reading inputs, storing outputs, performing SIMD processing of the RGB channels and branching are combined. Each instruction consists of an op-code 810 , a destination descriptor 812 and two source descriptors 814 , 816 . The op-code 810 can be related to a set of mnemonics 830 for the supported operations. The disclosed blender device is fully programmable, supporting any possible blending function. Some basic blending operations that are supported are shown in FIG. 7 . The source 710 and the destination 720 are two input pixel fragments that can be blended in any of the shown manners. The disclosed blending device also supports the blending modes defined by OpenVG: TABLE 2 OpenVG Blending Modes Name color Function Source c src Source over Destination c src + (1 − α src )*c dst Destination over Source c src *(1 − α dst ) + c dst Source in Destination c src *a dst Destination in Source c dst *a src Multiply α src *c src *(1 − α dst ) + α dst *c dst *(1 − α src ) + α src *c src *α dst *c dst Screen α src *c src + α dst *c dst − α src *c src *α dst *c dst Darken min(α src *c src + α dst *c dst *(1 − α src ), α dst *c dst + α src *c src *(1 − α dst )) Lighten max(α src *c src + α dst *c dst *(1 − α src ), α dst *c dst + α src *c Src *(1 − α dst )) The disclosed blending device also supports the OpenGL blending modes, where the function is c=c src *F src +c dst *F dst : TABLE 3 Blending modes defined for OpenGL Name F src , F dst Zero (0, 0) One (1, 1) Source color (C src , α src ) One Minus Source color (1 − C src , 1 − α src ) Destination color (C dst , α dst ) One Minus Destination color (1 − C dst , 1 − α dst ) Source Alpha (α src , α src ) One Minus Source Alpha (1 − α src , 1 − α src ) Destination Alpha (α dst , α dst ) One Minus Destination Alpha (1 − α dst , 1 − α dst ) Source Alpha Saturate min(α src , 1 − α dst ) To illustrate the functionality of the said blending device, an example of a specific operation is presented. The example shows the instruction sequence for implementing a “Source Over” blending operation with non-premultiplied inputs, as defined by the formula: c src * α src + ( 1 - α src ) * c dst * α dst α src + ( 1 - α src ) * α dst The corresponding VLIW instructions are shown in the following listing. 1: MUL P0, Cs, As NOP LDR Pa, As MUL Pb, Ad, (1 − As) 2: MUL P1, Cd, ADD Pc, Pa, Pb NOP NOP (1 − As) 3: MUL P2, P1, Ad ADD P3, P0, P2 NOP RCP Pd, Pc 4: MUL P1, P3, Pd NOP OUT P1, Pa NOP The first VLIW instruction multiplies source color with source alpha c src *α src storing the result in an intermediate register P 0 , multiplies destination alpha with the inverse of source alpha (1−α src )*α dst and prepares the denominator α src +(1−α src )*α dst in a register Pc. The second instruction finds the reciprocal of Pc into a register Pd, and multiplies destination color c dst with (1−α src ) storing this in register P 1 . The third instruction multiplies P 1 with the destination alpha and adds P 0 and P 2 , the two parts of the nominator. The fourth VLIW line finalizes calculation by multiplying the nominator P 3 with the reciprocal of the denominator Pd. It also sends a command to the output selection blocks 512 , 514 to provide the results (P 1 and Pa) to the output of the blender on the following clock cycle. *Work that led to the development of this invention, was co-financed by Hellenic Funds and by the European Regional Development Fund (ERDF) under the Hellenic National Strategic Reference Framework (NSRF) 2007-2013, according to Contract no. MICRO2-035 of the Project “TSi-ThinkVG” within the Programme “Hellenic Technology Clusters in Microelectronics—Phase-2 Aid Measure”.
The disclosed invention provides a solution for the problem of blending colors in a graphics processing unit. The plurality of blending equations used in various graphics layers is performed with a programmable streaming processor. Multiple simultaneous threads are used to eliminate pipeline latency and memory stalls. Overlays of predefined blending modes are used to minimize the time instruction memory is updated. The processing unit includes: (a) an instruction memory (b) hardware context registers for each executing stream (c) pipelined arithmetic units of predefined precision, including support for floating point (d) units that convert multi-format data to and from floating point precision (e) Look-up tables for quick color space transformations.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "BACKGROUND OF THE INVENTION The disclosed invention is related to graphics display technology, and more specifically to methods for blending colors in a graphics processing unit.", "Color blending is a process which combines color channels and alpha channels from sources of image information in order to generate modified image information.", "One such method has been described by Thomas Porter and Tom Duff in “Compositing Digital Images”, Computer Graphics, 18(3), July 1984, 253-259.", "Blending is required in systems like computer-generated graphics, image fusion for visualisation, graphical user interfaces etc.", "and is usually part of a Graphics Processing Unit (GPU), i.e. of a device that can render graphic images to be displayed on computer screens.", "Image blending was used from the start of motion picture generations (U.S. Pat. No. 1,262,954).", "Blending was part of computer-based image processing since its origins (U.S. Pat. Nos. 4,384,338, 4,679,040, 4,827,344).", "Original blender implementations were based on image multiplexing at the output to a screen via analog circuitry or on software programmes running on standard processors.", "This method is suitable for applications where high-speed software processing resources are available or where there is no high-speed requirement for the generation of the output images, as is the case with photograph editing.", "In order to be able to process blending in real time systems, a hardware blender is required.", "Methods that implement blending in hardware have been proposed as described in the following paragraphs: One of the first architectures of a blending apparatus was suggested in U.S. Pat. No. 5,592,196.", "This apparatus includes instructions for implementing the blending functions.", "These instructions are included in tables which form a blending mode, making the method fast but not as flexible as a full programmable approach.", "A hardware implementation of blending targeted explicitly to 3D graphics has been disclosed in U.S. Pat. No. 5,754,185.", "This method did not include any programmability mechanism but rather defined blending mode via control signals.", "Another hardware implementation is described in U.S. Pat. No. 5,896,136.", "This description mentions a unit that implements blending equations by using an alpha channel of lower resolution than the RGB channels.", "In a structure described in U.S. Pat. No. 7,397,479 a method for providing programmable combination of pixel characteristics is disclosed.", "Methods for implementing programmable blending were disclosed with patent application US 2006/192788 and U.S. Pat. No. 7,973,797.", "In both cases, the instructions for blending are provided by a processing unit loading formula or operation descriptors as a sequence to be executed by the blending hardware.", "Blending in the above referenced cases is defined as the process of generating a target pixel fragment value (T) by combining various inputs: a said source pixel fragment (S), a said destination pixel fragment (D) and corresponding alpha values (A s , A d ) for the source and destination pixels.", "Depending on the blending mode a different function (f) is applied in order to calculate the target.", "For calculating the target (T=f(S, A s , D, A d )), an arithmetic and logical unit (ALU) is employed that uses the said inputs and the blending mode in order to produce the target value.", "For many blending modes, computing the formula in a single operation requires complex hardware.", "In order to minimize hardware using simpler operators, the outputs can re-enter the ALU a second time or more until the formula is calculated.", "During this iterative process the blender cannot receive new inputs, thus complex blending modes result in lower overall throughput of the GPU.", "One method to achieve higher throughput is to implement the ALU as a pipeline of at least two threads.", "If the input pixel fragments can be provided in a continuous flow, the pipeline can produce one output per each clock cycle.", "The current state of the art in color blending devices as described above provides fast and programmable functionality.", "Many different operations—from a predefined set—can be performed on sequences of pixel fragments, where each pixel is represented as a color (c, usually R,G,B) and alpha (α) combination.", "One shortcoming of current implementations is that they are best fit for systems where the locations of subsequent pixel fragments are more or less continuous.", "In a modern GPU system like the one shown in FIG. 2 , Shader 206 processing and communication to the main memory for reading and writing pixel fragments is a bottleneck.", "Thus, the system cannot generate a steady flow of continuous pixel fragments.", "Another limitation is that most current implementations operate on integer or fixed-point representations.", "This makes it harder to interface with floating-point pixel sources and frame buffers.", "Furthermore, this limits the dynamic range of color representation for each pixel fragment.", "Another limitation of most current solutions is that the programmability is constrained by a few predefined operators.", "In one case only (U.S. Pat. No. 7,973,797), the operation is guided by two instructions which can be configured by other entities in the GPU.", "A more flexible approach is required for full programmability, where any sequence of instructions including flow control can be provided as input in the form of a small program for the blender core.", "All existing implementations support the RGBA color scheme that is very common in computer graphics;", "each pixel fragment is represented by three color channels of Red, Green and Blue (RGB) and an Alpha channel (A).", "However, if one has to blend non-RGBA pixel fragments (for example pixels in YUVA representation commonly used in video and photography), there needs to be another step of color space conversion, consuming time and bandwidth.", "SUMMARY OF THE INVENTION The disclosed apparatus provides color blending functionality with fully programmable sequences of operations on the source and destination pixel fragments.", "The architecture of the device is based on the observation that modern graphics systems do not generate steady flow of pixel fragments, leaving the blender with unused processing capability.", "The disclosed blender takes advantage of this fact in order to multiplex in time many blending functions on different fragments of pixels.", "This is achieved by the multithreading capability of the blender core.", "The disclosed device is a blender which is build around arithmetic and logic units (ALUs) that implement a plurality of blending functions as defined by a sequence of instructions.", "The core of the said blender is capable of pipelining the instructions in order to achieve high throughput of results.", "Furthermore, the said blending core can handle instructions from a plurality of sequences and operate on a plurality of input streams.", "This feature of the said blending core provides for multithreaded operations, thus minimizing the time a blender has to wait for non-continuous pixel fragments to be fetched from a memory.", "The disclosed blending device consists of (a) circuitry that reads, reformats and aligns pixel fragments from two inputs, (b) a blending core that can execute threads of instruction sequences in order to generate a result and (c) an output selection and reformatting circuitry that produces the final output pixel fragments.", "In one embodiment, the disclosed apparatus will be able to run the following operations: Blending of source &", "destination pixel fragments according to alpha values and a chosen mode.", "Concurrent multithreaded processing of a plurality of pixel fragments with different blending functions applied to each pixel fragment.", "Implementation of a wide variety of blending modes including the ones defined in the Khronos group standards OpenGL and OpenVG, regardless if the input or output streams are premultiplied or non-premultiplied.", "Conversion from RGB to YUV color space and vice versa.", "Gamma/degamma color correction.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a typical minimal embedded system-on-chip with a graphics processing unit.", "FIG. 2 shows a top level block diagram of a graphical processing unit (GPU) that is implemented using the disclosed blending device.", "FIG. 3 shows a possible structure of the disclosed blending device.", "FIG. 4 contains a block diagram of a possible embodiment of the core multi-threaded blender.", "FIG. 5 shows the internal structure of the ALU blocks of FIG. 4 .", "FIG. 6 presents the structure of a possible embodiment of an operations pipeline.", "FIG. 7 presents some blending mode examples.", "FIG. 8 shows a possible structure for the instructions used by the blender.", "DETAILED DESCRIPTION OF THE INVENTION Usage Graphics Processing Units (GPUs) are increasingly required to perform a plurality of blending functions.", "When projecting glyphs or user interface items like icons, buttons or window frames over an image, or when combining images from different sources, or when drawing a 3D scene with items on the foreground and items on the background, or when translucent items are displayed, in all those cases a target pixel value on the display is the result of the combination of two input pixel fragments weighted by a value called the alpha of that pixel fragment.", "Some examples of blending modes are described in table 1, which are defined in the Qt application framework: TABLE 1 Blending mode examples Name Description Source Over/ The alpha of the source is used to blend the pixel on top of the Destination Over destination.", "Destination Over is the inverse of Source Over.", "Clear The pixels in the destination are cleared (set to fully transparent) independent of the source.", "Source/ The output is the source/destination pixel.", "Destination Source In/ The output is the source, where the alpha is reduced by that of Destination In the destination.", "Destination In is the inverse of Source In.", "Source Out/ The output is the source, where alpha is reduced by the inverse Destination Out of destination.", "Destination Out is the inverse of Source Out.", "Source Atop/ The source pixel is blended on top of the destination, with the Destination Atop alpha of the source pixel reduced by the alpha of the destination pixel.", "Destination Atop is the inverse of Source Atop.", "Xor The source, whose alpha is reduced with the inverse of the destination alpha, is merged with the destination, whose alpha is reduced by the inverse of the source alpha.", "Plus Both the alpha and color of the source and destination pixels are added together.", "Multiply The output is the source color multiplied by the destination..", "Screen The source and destination colors are inverted and then multiplied.", "Overlay Multiplies or screens the colors depending on the destination color.", "The destination color is mixed with the source color to reflect the lightness or darkness of the destination.", "Darken The darker of the source and destination colors is selected.", "Lighten The lighter of the source and destination colors is selected.", "Color Dodge The destination color is brightened to reflect the source color.", "A black source color leaves the destination color unchanged.", "Color Burn The destination color is darkened to reflect the source color.", "A white source color leaves the destination color unchanged.", "Hard Light Multiplies or screens the colors depending on the source color.", "A light source color will lighten the destination color, whereas a dark source color will darken the destination color.", "Soft Light Darkens or lightens the colors depending on the source color.", "Similar to HardLight.", "Difference Subtracts the darker of the colors from the lighter.", "Painting with white inverts the destination color, whereas painting with black leaves the destination color unchanged.", "Exclusion Similar to Difference, but with a lower contrast.", "Painting with white inverts the destination color, whereas painting with black leaves the destination color unchanged.", "Source Or/And/ Does a bitwise OR/AND/XOR operation on the source and Xor Destination destination pixels (src OR dst).", "Not Source And Does a bitwise NOR operation on the source and destination Not Destination pixels ((NOT src) AND (NOT dst)).", "Other similar modes are also defined: ((NOT src) OR (NOT dst)), ((NOT src) XOR dst), (NOT src), ((NOT src) AND dst), (src AND (NOT dst)).", "The example diagram of FIG. 1 shows a typical system that performs graphics processing.", "The system connects all devices through a Bus Fabric 110 and is controlled by a Central Processing Unit (CPU) 102 .", "Graphics and Imaging functionality is performed in a Graphics Processing Unit (GPU) 200 .", "The program for the CPU and the GPU as well as the images handled by them are stored in a Memory 104 .", "The display of the system is updated through a Display Controller 106 .", "In one embodiment of the disclosed invention, the GPU and the display controller are connected through a direct link 108 for frame synchronization and bandwidth shaping.", "An abstract diagram of the GPU 200 from FIG. 1 is given in FIG. 2 .", "Connections to the CPU 212 and the Memory 214 are shown as direct links for simplicity, although they are typically implemented through a bus fabric.", "A Primitive Generator 204 block is used to create vectors, polygons, triangles, curves etc.", "as described in documents like U.S. Pat. No. 5,303,321.", "The core of the GPU is a processing unit, the Shader 206 , which calculates graphics functions in order to determine pixel fragment color and transparency values.", "One or more of said Shaders can exist in a GPU, each one dealing in parallel to the others with separate primitives or fragments.", "The output of the said Shader can be processed by units 208 that accelerate the generation of texture elements.", "Pixel fragments from the Shader are provided as input to a Blender 300 , which implements color/alpha blending.", "The Blender interfaces with the memory 214 for reading background image fragments and in order to store the blended output.", "Structure The disclosed apparatus is hereby described by reference to the block diagram of FIG. 3 .", "This block diagram shows the units that constitute the said blending device ( 300 in FIG. 2 ).", "The block diagram also shows connections between the units.", "The disclosed blending device operates on input streams of pixel fragments.", "One input is the stream of source fragments 302 which is typically provided by a Shader.", "If the blending mode requires that the output solely depends on the said incoming fragments, then the data simply enters the Source Reformat and clamping circuit 308 .", "If the decision is made 304 that a Destination Fragment is also required, then a request to the memory is issued 318 , and the operation waits until the said destination fragment is received 320 , and reformatted and clamped 306 .", "The two input streams come from different sources and need alignment 310 in order to be processed while maintaining spatial coherency.", "Processing is performed by the core 400 of the said blending device.", "The output of the core may have to be reformatted 312 if the target frame buffer uses a different pixel format.", "The same block 312 also performs color dithering in order to enhance the visual experience.", "When multiple outputs are generated, other circuitry 314 re-orders and aligns the pixel data so that they can be stored in the memory's frame buffer 316 .", "The core of the disclosed blending device is a Blender Core 400 which is multi-threaded.", "By allocating processing resources to more than one thread of execution, the blender core can multiplex in time a number of parallel blending operations, hiding the latency of arithmetic units, hiding the latency of reading fragments and sustaining throughput.", "FIG. 4 shows a possible embodiment of the said multi-threaded blender core.", "A brief description of the structure follows.", "The said blender core reads two aligned and appropriately preformatted pixel fragments, the source 404 and the destination 402 , consisting of color and alpha information for each input including possible stencil information in the alpha channel.", "The two inputs are maintained 406 until a processing slot in the arithmetic logic units becomes available.", "There are two arithmetic logic units ALUs, one for performing operations with the Alpha channel 430 and one for performing SIMD operations with the color channels 420 .", "The ALUs perform operations by reading a sequence of instructions from the Instruction Memory Contexts 410 .", "Multiple contexts exist in order to support multithreading.", "Each instruction sequence forms a small program that is executed by the disclosed blender core utilizing the operators in the said ALUs.", "The ALUs can also employ temporary data storage and look-up tables 408 to perform certain operations.", "The results from the blender core ALUs are selected 412 as defined in the instructions by the output circuitry and appropriately converted 414 to a suitable output pixel format, for example floating point (GL_RGBA32F, GL_RGBA16F), fixed point, RGB888, RGB565 etc.", "The output from the said blender core can be stalled based on a signal 108 from the display controller 106 , indicating high risk of data starvation which might lead to loss of visible frames.", "The internal structure of the ALUs of the disclosed blander core is shown in FIG. 5 .", "As stated, the inputs are pixel fragments formatted for blending.", "One is the source pixel fragment that consists of source color 502 and source alpha 504 .", "The second is the destination pixel fragment which consists of destination color 506 and destination alpha 508 .", "The output is a pixel fragment represented by its color channels 516 and its alpha 518 .", "The color ALU 420 in the diagram contains three parallel operation pipeline blocks 522 , 524 , 526 so that it can support up to three color channels.", "Other embodiments with less or more color channels are also possible.", "The output of each operation pipeline block can be fed back 510 to the ALU for a subsequent processing step or can be forwarded to one of a multitude of intermediate registers 528 , 529 .", "The Alpha ALU 430 contains one operation pipeline block 432 similar to the said operation pipeline blocks of the color ALU.", "The result is stored in a couple of intermediate registers 538 , 539 or fed back 510 to the inputs of the ALUs for the next step in the blending sequence.", "The output of the said color ALU is generated by combining or selecting 512 from the said two or more intermediate registers 528 , 529 and storing the result in the target pixel color 516 .", "The output of the said alpha ALU is generated by combining or selecting 514 from the said two intermediate registers 538 , 539 and storing the result in the target pixel alpha 518 .", "The detail of each ALU operation pipeline block is shown in a possible embodiment in FIG. 6 .", "The instructions are fetched for multiple threads from the instruction memory contexts 410 .", "A dedicated fetch logic circuitry 418 chooses one instruction from each active thread per clock and feeds them 660 to the internal pipeline stages of the ALU operation.", "The figure shows an example with four threads A, B, C and D. The first instruction from each thread —instr0— is already in the pipeline, the second instruction from each thread —instr1— is ready to be executed, and the following instructions—inst2, instr3, instr4—wait in the memory contexts.", "The first stage is instruction decode 622 which determines the type of instruction and the corresponding operator 632 that must be used.", "It is possible that the instruction op-code affects directly the next instruction that needs to be fetched, thus executing a non-conditional branch.", "This branch request 642 is reported to the instruction fetch logic 418 .", "Data are fetched 624 at the same clock cycle with instruction decode from the input port 610 of the ALU which can be connected to a previous output of the same or another ALU operations pipeline or to a temporary location in memory or to a look-up table.", "Fetched data are fed to the next pipeline stage via registers 634 .", "The core operators of each currently processed instruction are in the subsequent pipeline stages 626 , 628 , 630 .", "Operators include multiplication, addition, subtraction, logical operators, reciprocal and floor/ceiling.", "The result is stored in pipeline registers 636 , 638 , 640 and the flags 644 generated by the operation are reported to the instruction fetch logic.", "The described embodiment uses three pipeline stages for the operators;", "alternative implementations can include more or less stages to achieve an optimum trade-off between complexity, throughput, latency and number of threads that can be supported.", "The output from the last stage of the pipeline 640 is directly placed on the port of the ALU operations pipeline 650 .", "Depending on the op-code, the output can be fed back for a next instruction through the ALU or placed on the output register if processing of the specific data has finished.", "A possible embodiment of the disclosed invention will include an instruction code structured as: [OC: Op-code][DS: Destination][(S1: Source of input A][S2: Source of input B] and four or more such instructions will constitute a very long instruction word (VLIW) instruction for the entire blending core.", "This is further illustrated in FIG. 8 .", "The entire VLIW instruction 820 that goes through the operating units consists of three or more instructions for the color channel pipelines and one instruction for the alpha pipeline.", "In each VLIW instruction, operations for reading inputs, storing outputs, performing SIMD processing of the RGB channels and branching are combined.", "Each instruction consists of an op-code 810 , a destination descriptor 812 and two source descriptors 814 , 816 .", "The op-code 810 can be related to a set of mnemonics 830 for the supported operations.", "The disclosed blender device is fully programmable, supporting any possible blending function.", "Some basic blending operations that are supported are shown in FIG. 7 .", "The source 710 and the destination 720 are two input pixel fragments that can be blended in any of the shown manners.", "The disclosed blending device also supports the blending modes defined by OpenVG: TABLE 2 OpenVG Blending Modes Name color Function Source c src Source over Destination c src + (1 − α src )*c dst Destination over Source c src *(1 − α dst ) + c dst Source in Destination c src *a dst Destination in Source c dst *a src Multiply α src *c src *(1 − α dst ) + α dst *c dst *(1 − α src ) + α src *c src *α dst *c dst Screen α src *c src + α dst *c dst − α src *c src *α dst *c dst Darken min(α src *c src + α dst *c dst *(1 − α src ), α dst *c dst + α src *c src *(1 − α dst )) Lighten max(α src *c src + α dst *c dst *(1 − α src ), α dst *c dst + α src *c Src *(1 − α dst )) The disclosed blending device also supports the OpenGL blending modes, where the function is c=c src *F src +c dst *F dst : TABLE 3 Blending modes defined for OpenGL Name F src , F dst Zero (0, 0) One (1, 1) Source color (C src , α src ) One Minus Source color (1 − C src , 1 − α src ) Destination color (C dst , α dst ) One Minus Destination color (1 − C dst , 1 − α dst ) Source Alpha (α src , α src ) One Minus Source Alpha (1 − α src , 1 − α src ) Destination Alpha (α dst , α dst ) One Minus Destination Alpha (1 − α dst , 1 − α dst ) Source Alpha Saturate min(α src , 1 − α dst ) To illustrate the functionality of the said blending device, an example of a specific operation is presented.", "The example shows the instruction sequence for implementing a “Source Over”", "blending operation with non-premultiplied inputs, as defined by the formula: c src * α src + ( 1 - α src ) * c dst * α dst α src + ( 1 - α src ) * α dst The corresponding VLIW instructions are shown in the following listing.", "1: MUL P0, Cs, As NOP LDR Pa, As MUL Pb, Ad, (1 − As) 2: MUL P1, Cd, ADD Pc, Pa, Pb NOP NOP (1 − As) 3: MUL P2, P1, Ad ADD P3, P0, P2 NOP RCP Pd, Pc 4: MUL P1, P3, Pd NOP OUT P1, Pa NOP The first VLIW instruction multiplies source color with source alpha c src *α src storing the result in an intermediate register P 0 , multiplies destination alpha with the inverse of source alpha (1−α src )*α dst and prepares the denominator α src +(1−α src )*α dst in a register Pc.", "The second instruction finds the reciprocal of Pc into a register Pd, and multiplies destination color c dst with (1−α src ) storing this in register P 1 .", "The third instruction multiplies P 1 with the destination alpha and adds P 0 and P 2 , the two parts of the nominator.", "The fourth VLIW line finalizes calculation by multiplying the nominator P 3 with the reciprocal of the denominator Pd.", "It also sends a command to the output selection blocks 512 , 514 to provide the results (P 1 and Pa) to the output of the blender on the following clock cycle.", "*Work that led to the development of this invention, was co-financed by Hellenic Funds and by the European Regional Development Fund (ERDF) under the Hellenic National Strategic Reference Framework (NSRF) 2007-2013, according to Contract no. MICRO2-035 of the Project “TSi-ThinkVG”", "within the Programme “Hellenic Technology Clusters in Microelectronics—Phase-2 Aid Measure.”" ]
This application claims the benefit of U.S. Provisional Application No. 60/054,860, filed on Aug. 6, 1997. BACKGROUND OF THE INVENTION A key step in the synthesis of the reverse transcriptase inhibitor, (-)-6-chloro-4-cyclopropylenthynyl-4-triflouromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one, also known as DMP-266, is the chiral addition to the 2-flouromethylcarbonyl-4-choloroanaline using cyclopropyl acetylene as a nucleophile, a chiral additive, a non-chiral additive, and an organic. The syntheses of DMP-266 and structurally similar reverse transcriptase inhibitors are disclosed in U.S. Pat. No. 5,519,021, and the corresponding PCT International Patent Application WO 95/20389, which published on Aug. 3, 1995. Additionally, the asymmetric synthesis of an enantiomeric benzoxazinone by a highly enantioselective acetylide addition and cyclization sequence has been described by Thompson, et al., Tetrahedron Letters 1995, 36, 8937-8940, as well as the PCT publication, WO 96/37457, which published on Nov. 28, 1996. Additionally, several applications have been filed which disclose various aspects of the synthesis of (-)-6-chloro-4-cyclopropylethynyl-4-triflouromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one, including: 1) a process for the preparation of cyclopropylacetylene by cyclizing 5-halo-1-pentyne published on Aug. 1, 1996 in PCT Publication No. WO 96/22955; 2) a process for making the chiral alcohol, U.S. Ser. No. 60/035,462, filed Jan. 14, 1997; 3) the chiral additive, U.S. Ser. No. 60/034,926, filed Jan. 10, 1997; 4) the cyclization reaction, U.S. Ser. No. 60/037,059, filed Feb. 12, 1997; 5) the anti-solvent crystallization procedure, Case No. 19905PV2 (U.S. Serial No. unknown), filed May 23, 1997. Several methods have been described in published literature for preparation of cyclopropylacetylene. C. E. Hudson and N. L. Bauld, J.A.C.S. 94:4, p.1158 (1972); J. Salaun, J.O.C. 41:7 p.1237 (1976); and W. Schoberth and M. Hanack, Synthesis (1972). p.703 disclose methods for the preparation of cyclopropylacetylene by dehydrohalogenating 1-cyclopropyl-1,1-dichloroethane. Miltzer, H. C. et al., Synthesis, 998 (1993) disclose a method for preparation of cyclopropylalkenes by halogenating an enolether, reacting the alkyl 1,2-dihaloether with propargyl magnesium bromide, and cyclizing to give a 2-alkoxy -1-ethynylcyclopropane. F. A. Carey and A. S. Court, J. Org. Chem., Vol. 37, No.12, (1972) p. 1926 disclose the use of a modified Wittig-Horner olefin synthesis for organcic transformations; D. J. Peterson, J. Org. Chem., Vol. 20C, No. 33, (1968) p. 780 describes the application of olfenation to make vinyl sulfides and H. Takeshita and T. Hatsui, J. Org. Chem., Vol. 43, No. 15, (1978) p. 3083 disclose the use of potassium 3-aminopropylamide in base-catalyzed prototropic reactions. As illustrated by the Scheme below, Schoberth, et al., describes a method which resulted in about a 42% yield of the cyclopropylacetylene. ##STR1## The instant invention discloses a more efficient process for the synthesis of this important substrate. SUMMARY OF THE INVENTION The present invention relates to a process for the preparation of cyclopropyl acetylene (CPA), represented by formula I: ##STR2## which comprises reacting thioanisole represented by formula II: ##STR3## wherein X is H, halo, CF 3 , or C 1-6 alkyl; in the presence of a base and a silylating agent, to a compound represented by formula III: ##STR4## wherein each R is independently a C 1-6 alkyl and X is described above; reacting a compound of formula III with a compound of formula IV: ##STR5## in the presence of a base to yield vinyl thioethers, represented by formula V and VI: ##STR6## reacting a compound of formula V and VI in the presence of potassium diaminopropane (KAPA) to yield cyclopropyl acetylene. This process is a more facile and efficient alternative to known synthetic pathways insofar as the entire scheme can be carried out in a single eaction vessel by sequential addition of the required reagents. DETAILED DESCRIPTION OF THE INVENTION The instant invention relates to a process for the preparation of cyclopropyl acetylene (CPA), represented by formula I: ##STR7## First, a solution of thioanisole, represented by formula II: ##STR8## wherein X is H, halo, CF 3 , or C 1-6 alkyl; is reacted in the presence of a base and a silylating agent to yield a compound represented by formula III: ##STR9## wherein X and R are described above, For purposes of this invention, the base employed is an alkyl lithium such as phenyl lithium, Butyl lithium (BuLi) or a potassium alkyl such as potassium methyl and the like, preferably BuLi and the silylating agent employed is selected from the group consisting of trialkylsilylchlorides, triakylsilyliodides and triflates such as trimethylsilylchloride, triethylsilylchloride, t-butyldimethylsilyl chloride, t-butyldiphenylsilylchloride, trimethylsilyltriflate, t-butyldimethylsilyltriflate, triethylsilyltriflate, triethylsilyliodide and the like, preferably trimethylsilylchloride (TMSCl). The solution of thioanisole, consisting of thioanisole and a protic solvent such as tetrahydrofuran (THF), is cooled to a temperature of about -100° C. to about -60° C., preferably -95° C. to about -70° C. before contact with the strong base. Upon contact with the base the solution is warmed to a temperature of about -5° C. to about 5° C., preferably about -2° C. to about 1° C. for approximately 10 minutes to about one hour and then cooled to a temperature of about -100° C. to about -60° C. preferably -95° C. to about -70° C. before contact with the silylating agent. After addition of the silyating agent the mixture is warmed to a temperature of about -5° C. to about 5° C., preferably about -2° C. to about 1° C. for approximately 10 minutes to about one hour. Next, Compound III is reacted with a compound of formula IV: ##STR10## in the presence of a base to yield vinyl thioethers, represented by formula V and VI: ##STR11## For purposes of this invention, the base employed is an alkyl lithium such as phenyl lithium, Butyl lithium (BuLi) or a potassium alkyl such potassium methyl and the like, preferably BuLi. The solution of Compound III is cooled to a temperature of about -100° C. to about -60° C., preferably -95° C. to about -70° C. before contact with compound IV. Finally, Compound V and VI are then reacted in the presence of potassium diaminopropane (KAPA) to yield the desired product, cyclopropyl acetylene (CPA). The term alkyl relates to lower alkyls such as methyl, ethyl, isopropyl, butyl, propyl and the like. The term halo relates to fluoro, chloro, iodo and bromo. CPA can be isolated, after aqueous quench of the reaction, by extraction into an organic solvent, such a s hexane or toluene. Alternatively, CPA can be isolated and purified by distillation. The reagents used in this process are either commercially available or may be prepared by synthetic methods commonly known in the art. KAPA may be generated from KH and diamino propane by methods known in the art. Some of the intermediate compounds synthesized in the present invention occur as geometric isomers. The processes of synthesizing all such isomers are included in the present invention. In another preferred aspect of this invention, Compound IV is cyclopropyl carboxaldehyde. The present invention is embodied by the following non-limiting example. EXAMPLE Reaction Scheme ##STR12## Procedure Step 1 A solution of thioanisole (4.7 g, 1.05 mmoles) in 19 ml of THF was cooled to -78° C. and a hexane solution of butyl lithium (14.5 ml 2.05 mmoles) was added and the solution was warmed to 0° C. for 30 minutes to complete anion formation. After this the solution was cooled to -78° C. and trimethylsilyl chloride (4 g, 1.03 mmoles) was added, followed by warming to 0° C. for 30 minutes. Step 2 The resulting mixture was cooled again to -78° C. before another portion of butyl lithium (14.4 ml, 2.05 mmole) was added. After warming and aging at 0° C. for 30 minutes, cyclopropyl carboxaldehyde(2.5 g, 1.0 mmole) was added at -78° C. The mixture was stirred overnight at room temperature and then quenched with 100 ml of water. The organic product was extracted with 40 ml of hexane followed by evaporation. The NMR spectrum indicated that a mixture of E and Z thiovinyl ethers 3 and 4 were produced. Alternatively, commercially available TMS thioanisole may be employed and the reaction initiated at Step 2 according to the following procedure: A solution of (phenylthiomethyl)trimethylsilane 2 ml (10 mmole) in THF(5 ml) was cooled to -78° C. and a hexane solution of butyllithium (4.5 ml ,2.25 mmole) was added. The solution was allowed to warm to room temperature, then it was cooled again to -78° C. and cyclopropane carboxaldehyde (0.75 ml, 10 mmole) was added dropwise. The reaction mixture was kept at -78° C. for an additional two hours and then it was allowed to warm to room temperature. The mixture was extracted with water and the solvent was removed to give an oil. The NMR spectrum of this mixture was identical with that of the product obtained for synthesized TMS thioanisole, as described above. This mixture was used without purification for the next step. Step 3 A solution of the mixture of the vinyl sulfides 3 and 4, from the previous reactions, (176 mg, 0.85 mm) in diaminopropane (1 ml) was cooled with ice and a solution of KAPA (potassium diaminopropane, 2 mmoles) in 2 ml of diaminopropane was added. After this the solution was allowed to stir at room temperature for 18 hr. A GC assay indicated that 41 mg cyclopropyl acetylene was produced in 62% yield.
An efficient and facile process for the preparation of cyclopropylacetylene from thioanisole and cyclopropyl substituted ketones or aldehydes is disclosed.
Briefly summarize the main idea's components and working principles as described in the context.
[ "This application claims the benefit of U.S. Provisional Application No. 60/054,860, filed on Aug. 6, 1997.", "BACKGROUND OF THE INVENTION A key step in the synthesis of the reverse transcriptase inhibitor, (-)-6-chloro-4-cyclopropylenthynyl-4-triflouromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one, also known as DMP-266, is the chiral addition to the 2-flouromethylcarbonyl-4-choloroanaline using cyclopropyl acetylene as a nucleophile, a chiral additive, a non-chiral additive, and an organic.", "The syntheses of DMP-266 and structurally similar reverse transcriptase inhibitors are disclosed in U.S. Pat. No. 5,519,021, and the corresponding PCT International Patent Application WO 95/20389, which published on Aug. 3, 1995.", "Additionally, the asymmetric synthesis of an enantiomeric benzoxazinone by a highly enantioselective acetylide addition and cyclization sequence has been described by Thompson, et al.", ", Tetrahedron Letters 1995, 36, 8937-8940, as well as the PCT publication, WO 96/37457, which published on Nov. 28, 1996.", "Additionally, several applications have been filed which disclose various aspects of the synthesis of (-)-6-chloro-4-cyclopropylethynyl-4-triflouromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one, including: 1) a process for the preparation of cyclopropylacetylene by cyclizing 5-halo-1-pentyne published on Aug. 1, 1996 in PCT Publication No. WO 96/22955;", "2) a process for making the chiral alcohol, U.S. Ser.", "No. 60/035,462, filed Jan. 14, 1997;", "3) the chiral additive, U.S. Ser.", "No. 60/034,926, filed Jan. 10, 1997;", "4) the cyclization reaction, U.S. Ser.", "No. 60/037,059, filed Feb. 12, 1997;", "5) the anti-solvent crystallization procedure, Case No. 19905PV2 (U.S. Serial No. unknown), filed May 23, 1997.", "Several methods have been described in published literature for preparation of cyclopropylacetylene.", "C. E. Hudson and N. L. Bauld, J.A.C.S.", "94:4, p[.", "].1158 (1972);", "J. Salaun, J.O.C. 41:7 p[.", "].1237 (1976);", "and W. Schoberth and M. Hanack, Synthesis (1972).", "p[.", "].703 disclose methods for the preparation of cyclopropylacetylene by dehydrohalogenating 1-cyclopropyl-1,1-dichloroethane.", "Miltzer, H. C. et al.", ", Synthesis, 998 (1993) disclose a method for preparation of cyclopropylalkenes by halogenating an enolether, reacting the alkyl 1,2-dihaloether with propargyl magnesium bromide, and cyclizing to give a 2-alkoxy -1-ethynylcyclopropane.", "F. A. Carey and A. S. Court, J. Org.", "Chem.", ", Vol. 37, No[.", "].12, (1972) p. 1926 disclose the use of a modified Wittig-Horner olefin synthesis for organcic transformations;", "D. J. Peterson, J. Org.", "Chem.", ", Vol. 20C, No. 33, (1968) p. 780 describes the application of olfenation to make vinyl sulfides and H. Takeshita and T. Hatsui, J. Org.", "Chem.", ", Vol. 43, No. 15, (1978) p. 3083 disclose the use of potassium 3-aminopropylamide in base-catalyzed prototropic reactions.", "As illustrated by the Scheme below, Schoberth, et al.", ", describes a method which resulted in about a 42% yield of the cyclopropylacetylene.", "##STR1## The instant invention discloses a more efficient process for the synthesis of this important substrate.", "SUMMARY OF THE INVENTION The present invention relates to a process for the preparation of cyclopropyl acetylene (CPA), represented by formula I: ##STR2## which comprises reacting thioanisole represented by formula II: ##STR3## wherein X is H, halo, CF 3 , or C 1-6 alkyl;", "in the presence of a base and a silylating agent, to a compound represented by formula III: ##STR4## wherein each R is independently a C 1-6 alkyl and X is described above;", "reacting a compound of formula III with a compound of formula IV: ##STR5## in the presence of a base to yield vinyl thioethers, represented by formula V and VI: ##STR6## reacting a compound of formula V and VI in the presence of potassium diaminopropane (KAPA) to yield cyclopropyl acetylene.", "This process is a more facile and efficient alternative to known synthetic pathways insofar as the entire scheme can be carried out in a single eaction vessel by sequential addition of the required reagents.", "DETAILED DESCRIPTION OF THE INVENTION The instant invention relates to a process for the preparation of cyclopropyl acetylene (CPA), represented by formula I: ##STR7## First, a solution of thioanisole, represented by formula II: ##STR8## wherein X is H, halo, CF 3 , or C 1-6 alkyl;", "is reacted in the presence of a base and a silylating agent to yield a compound represented by formula III: ##STR9## wherein X and R are described above, For purposes of this invention, the base employed is an alkyl lithium such as phenyl lithium, Butyl lithium (BuLi) or a potassium alkyl such as potassium methyl and the like, preferably BuLi and the silylating agent employed is selected from the group consisting of trialkylsilylchlorides, triakylsilyliodides and triflates such as trimethylsilylchloride, triethylsilylchloride, t-butyldimethylsilyl chloride, t-butyldiphenylsilylchloride, trimethylsilyltriflate, t-butyldimethylsilyltriflate, triethylsilyltriflate, triethylsilyliodide and the like, preferably trimethylsilylchloride (TMSCl).", "The solution of thioanisole, consisting of thioanisole and a protic solvent such as tetrahydrofuran (THF), is cooled to a temperature of about -100° C. to about -60° C., preferably -95° C. to about -70° C. before contact with the strong base.", "Upon contact with the base the solution is warmed to a temperature of about -5° C. to about 5° C., preferably about -2° C. to about 1° C. for approximately 10 minutes to about one hour and then cooled to a temperature of about -100° C. to about -60° C. preferably -95° C. to about -70° C. before contact with the silylating agent.", "After addition of the silyating agent the mixture is warmed to a temperature of about -5° C. to about 5° C., preferably about -2° C. to about 1° C. for approximately 10 minutes to about one hour.", "Next, Compound III is reacted with a compound of formula IV: ##STR10## in the presence of a base to yield vinyl thioethers, represented by formula V and VI: ##STR11## For purposes of this invention, the base employed is an alkyl lithium such as phenyl lithium, Butyl lithium (BuLi) or a potassium alkyl such potassium methyl and the like, preferably BuLi.", "The solution of Compound III is cooled to a temperature of about -100° C. to about -60° C., preferably -95° C. to about -70° C. before contact with compound IV.", "Finally, Compound V and VI are then reacted in the presence of potassium diaminopropane (KAPA) to yield the desired product, cyclopropyl acetylene (CPA).", "The term alkyl relates to lower alkyls such as methyl, ethyl, isopropyl, butyl, propyl and the like.", "The term halo relates to fluoro, chloro, iodo and bromo.", "CPA can be isolated, after aqueous quench of the reaction, by extraction into an organic solvent, such a s hexane or toluene.", "Alternatively, CPA can be isolated and purified by distillation.", "The reagents used in this process are either commercially available or may be prepared by synthetic methods commonly known in the art.", "KAPA may be generated from KH and diamino propane by methods known in the art.", "Some of the intermediate compounds synthesized in the present invention occur as geometric isomers.", "The processes of synthesizing all such isomers are included in the present invention.", "In another preferred aspect of this invention, Compound IV is cyclopropyl carboxaldehyde.", "The present invention is embodied by the following non-limiting example.", "EXAMPLE Reaction Scheme ##STR12## Procedure Step 1 A solution of thioanisole (4.7 g, 1.05 mmoles) in 19 ml of THF was cooled to -78° C. and a hexane solution of butyl lithium (14.5 ml 2.05 mmoles) was added and the solution was warmed to 0° C. for 30 minutes to complete anion formation.", "After this the solution was cooled to -78° C. and trimethylsilyl chloride (4 g, 1.03 mmoles) was added, followed by warming to 0° C. for 30 minutes.", "Step 2 The resulting mixture was cooled again to -78° C. before another portion of butyl lithium (14.4 ml, 2.05 mmole) was added.", "After warming and aging at 0° C. for 30 minutes, cyclopropyl carboxaldehyde(2.5 g, 1.0 mmole) was added at -78° C. The mixture was stirred overnight at room temperature and then quenched with 100 ml of water.", "The organic product was extracted with 40 ml of hexane followed by evaporation.", "The NMR spectrum indicated that a mixture of E and Z thiovinyl ethers 3 and 4 were produced.", "Alternatively, commercially available TMS thioanisole may be employed and the reaction initiated at Step 2 according to the following procedure: A solution of (phenylthiomethyl)trimethylsilane 2 ml (10 mmole) in THF(5 ml) was cooled to -78° C. and a hexane solution of butyllithium (4.5 ml ,2.25 mmole) was added.", "The solution was allowed to warm to room temperature, then it was cooled again to -78° C. and cyclopropane carboxaldehyde (0.75 ml, 10 mmole) was added dropwise.", "The reaction mixture was kept at -78° C. for an additional two hours and then it was allowed to warm to room temperature.", "The mixture was extracted with water and the solvent was removed to give an oil.", "The NMR spectrum of this mixture was identical with that of the product obtained for synthesized TMS thioanisole, as described above.", "This mixture was used without purification for the next step.", "Step 3 A solution of the mixture of the vinyl sulfides 3 and 4, from the previous reactions, (176 mg, 0.85 mm) in diaminopropane (1 ml) was cooled with ice and a solution of KAPA (potassium diaminopropane, 2 mmoles) in 2 ml of diaminopropane was added.", "After this the solution was allowed to stir at room temperature for 18 hr.", "A GC assay indicated that 41 mg cyclopropyl acetylene was produced in 62% yield." ]
CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 12/169,751, filed Jul. 9, 2008; which claims the benefit of U.S. Provisional Patent Application Nos. 60/948,587, filed Jul. 9, 2007, and 60/949,085, filed Jul. 11, 2007, the contents of which are hereby incorporated by reference herein in their entirety. FIELD OF INVENTION The present application is related to wireless communication systems. BACKGROUND A dual-mode or multi-mode wireless transmit/receive unit has dual or multiple radio transceivers, each designed to communicate on a particular radio access technology (RAT), such as 3rd Generation Partnership Project (3GPP) and non-3GPP systems. The handover process between 3GPP and non-3GPP systems may be slow due to the nature of the system configurations and operations. One problem occurs when a WTRU moves from one system to another as the WTRU is required to register and authenticate in the other system. A similar problem exists for session initiation protocol (SIP)-based Session Continuity processes between 3GPP and non-3GPP systems. When moving from one system to the other, the WTRU is required to register and authenticate in the other system before registering with internet protocol (IP) multimedia subsystem (IMS). Another problem may occur due to the 3GPP prohibition against simultaneous radio transceiver operation. A single WTRU cannot have a 3GPP radio transceiver and a non-3GPP radio transceiver active at the same time. In such cases, dual-mode or multi-mode radio transceivers need sophisticated control of the radio switching. SUMMARY The present invention is related to a method and apparatus for session continuity using pre-registration tunneling procedure. For session continuity, a tunnel is established between a wireless transmit/receive unit (WTRU) and a core network of a target system via a source system while the WTRU is still connected with the source system. An access procedure is performed toward the target system using the tunnel. A handover is performed from the source system to the target system once the access procedure is complete. For session initiation protocol (SIP) based handover, the access procedure includes SIP registration, authentication of the WTRU at the target system, and internet protocol (IP) configuration. The handover may be from a third generation partnership project (3GPP) system to a non-3GPP system, or vice versa. BRIEF DESCRIPTION OF THE DRAWINGS A more detailed understanding of the invention may be had from the following description of a preferred embodiment, given by way of example and to be understood in conjunction with the accompanying drawings wherein: FIG. 1 shows a block diagram of dual protocol stack configuration in a dual mode wireless transmit/receive unit (WTRU) in accordance with a first embodiment; FIG. 2 shows a block diagram of a dual protocol stack configuration in a dual mode WTRU supporting pre-registration SIP-based session continuity in accordance with a second embodiment; FIGS. 3A and 3B show a signal diagram of a pre-registration procedure for a 3GPP to non-3GPP handover in accordance with the first embodiment; FIGS. 4A and 4B show a signal diagram of a pre-registration procedure for a non-3GPP to 3GPP handover in accordance with the first embodiment; FIGS. 5A , 5 B and 5 C show a signaling diagram of pre-registration procedures for 3GPP to non-3GPP handover in accordance with the second embodiment; FIGS. 6A , 6 B and 6 C show a signaling diagram of pre-registration procedures for non-3GPP to 3GPP handover in accordance with the second embodiment; FIG. 7 shows dual stack operation in a multi-mode WTRU supporting pre-registration SIP-based session continuity for 3GPP to non-3GPP handover in accordance with the second embodiment; and FIG. 8 shows dual stack operation in a multi-mode WTRU supporting pre-registration SIP-based session continuity for non-3GPP to 3GPP handover in accordance with the second embodiment. DETAILED DESCRIPTION When referred to hereafter, the terminology “WTRU” includes but is not limited to a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, a cellular telephone, a personal digital assistant (PDA), a computer, or any other type of user device capable of operating in a wireless environment. When referred to hereafter, the terminology “base station” includes but is not limited to a Node-B, a site controller, an access point (AP), or any other type of interfacing device capable of operating in a wireless environment. By way of reference, as a WTRU moves from a system A to a system B, system A is defined as the handover source and system B is defined as the handover target. One mechanism to speed access procedures to a target system is to allow pre-registration and pre-authentication procedures to be performed by upper layers in a WTRU via the source system. The source system may identify the target system, establish a tunnel between the WTRU and the core target network, (e.g., Autonomous Registration (AR) or Access, Authentication and Accounting (AAA)), and instruct the WTRU to start access procedures for the target network. Upon successful completion of the access procedure, the source network may instruct the WTRU to switch, or handover, to the target network and turn off the radio connected to the source network. FIG. 1 is a block diagram of dual protocol layer stack in a dual mode WTRU 101 supporting pre-registration tunneling in accordance with a first embodiment. As shown in FIG. 1 , the WTRU 101 includes a non-3GPP protocol layer stack comprising an application layer 110 , a mobility management (MM) layer 111 , a radio resource control (RRC) and media access control (MAC) layer 112 , and a physical (PHY) layer 113 . The application layer 110 is coupled to the MM layer 111 by path 115 . The MM layer 111 is coupled to the RRC/MAC layer 112 by path 116 . Path 117 couples the RRC/MAC layer 112 to the PHY layer 113 . Similarly, a 3GPP protocol layer stack comprises an application layer 120 , a multimedia (MM) layer 121 , a radio resource control (RRC) and media access control (MAC) layer 122 , and a physical (PHY) layer 123 . The application layer 120 is coupled to the MM layer 121 by path 125 . The MM layer 121 is coupled to the RRC/MAC layer 122 by path 126 . Path 127 couples the RRC/MAC layer 122 to the PHY layer 123 . The dual protocol layer stack is further configured to include a path 141 , which cross connects the non-3GPP PHY layer 113 to the 3GPP RRC/MAC layer 122 . A path 131 couples the 3GPP PHY layer 123 to the non-3GPP RRC/MAC layer 112 . These paths 131 and 141 are used to establish tunneling between 3GPP and non-3GPP systems to facilitate 3GPP to non-3GPP handover. A controller 151 controls the signaling for handover and access procedures executed at the protocol stack layers shown in FIG. 1 . FIG. 2 is a block diagram of dual protocol layer stack in a dual mode WTRU 201 supporting pre-registration tunneling in accordance with a second embodiment. As shown in FIG. 2 , the WTRU 201 includes a non-3GPP protocol layer stack comprising an application layer 210 , a session management (SM) and mobility management (MM) layer 211 , a radio resource control (RRC) and media access control (MAC) layer 212 , and a physical (PHY) layer 213 . The application layer 210 is coupled to the SM and MM layer 211 by path 215 . The SM and MM layer 211 is coupled to the RRC/MAC layer 212 by path 216 . Path 217 couples the RRC/MAC layer 212 to the PHY layer 213 . Similarly, a 3GPP protocol layer stack comprises an application layer 220 , a SM and MM layer 221 , a radio resource control (RRC) and media access control (MAC) layer 222 , and a physical (PHY) layer 223 . The application layer 220 is coupled to the SM and MM layer 221 by path 225 . The SM and MM layer 221 is coupled to the RRC/MAC layer 222 by path 226 . Path 227 couples the RRC/MAC layer 222 to the PHY layer 223 . The dual protocol layer stack is further configured to include a path 241 , which cross connects the non-3GPP PHY layer 213 to the 3GPP RRC/MAC layer 222 . A path 231 couples the 3GPP PHY layer 223 to the non-3GPP RRC/MAC layer 212 . These paths 231 and 241 are used to establish tunneling between 3GPP and non-3GPP systems to facilitate 3GPP to non-3GPP handover. A controller 251 controls the signaling for handover and access procedures executed at the protocol stack layers shown in FIG. 2 . FIGS. 3A and 3B show a signal diagram for pre-registration procedure for a handover of a WTRU 301 from a 3GPP handover source 304 to a non-3GPP handover target 305 . A WTRU 301 includes a 3GPP radio transceiver 302 and a non-3GPP radio transceiver 303 for communication with a 3GPP core network (CN) 304 and a non-3GPP CN 305 . For simplicity, a dual mode WTRU 301 is shown, however the signaling described herein is valid for a multi-mode WTRU having multiple 3GPP and non-3GPP radio transceivers. While shown as direct signals from the WTRU 301 and CNs 303 , 304 , the signals may be relayed by a NodeB or a base station entity (not shown). The pre-registration begins with the 3GPP transceiver 302 receiving a 3GPP and non-3GPP measurement list 311 from 3GPP CN 304 . The measurement list 311 identifies the channel frequencies of candidate handover targets. At 312 , the WTRU 301 stores the list in an internal memory, and for periodically initiating channel measurements. The 3GPP transceiver 302 sends an initialization signal 313 to the non-3GPP transceiver 303 , along with a list of candidate non-3GPP handover targets 314 . At 315 , the non-3GPP transceiver 303 is activated for a period in order to perform measurement procedures, in which it monitors channels and performs measurements. The non-3GPP transceiver 303 sends measurement reports 316 of the monitored channels to the 3GPP transceiver 302 . When measurement procedures by the non-3GPP transceiver 303 are completed, it may be deactivated. At 317 , the 3GPP transceiver 302 combines the measurements it made with those made by the non-3GPP transceiver 303 , formulates combined measurement reports, and transmits the combined measurement reports to the 3GPP CN 304 . At 318 , the 3GPP CN 304 examines the combined measurement reports and handover (HO) criteria, and selects a handover target system for the WTRU 301 . The 3GPP CN 304 sends a signal 319 to the target non-3GPP CN 305 to initiate a handover direct tunnel, and the target non-3GPP CN 305 responds with a tunnel establishment acknowledgment signal 320 . The 3GPP CN 304 sends a signal 321 to the 3GPP transceiver 302 to initiate a handover direct tunnel. This signal 321 may include a non-3GPP tunnel endpoint identification (TEID). The 3GPP transceiver 302 sends the target ID 322 to the non-3GPP transceiver 303 . The non-3GPP transceiver sends its handover direct tunnel acknowledgment (ACK) 323 to the 3GPP transceiver 302 , which is then forwarded to the 3GPP CN 304 as signal 324 . The direct handover tunnel 325 is established between the non-3GPP target CN 305 and the non-3GPP transceiver 303 . The source 3GPP CN 304 sends a signal 326 to initiate a non-3GPP registration to the 3GPP transceiver 302 which is then forwarded as signal 327 to the non-3GPP transceiver 303 . The upper layers of the non-3GPP transceiver 303 perform pre-registration pre-authentication procedures, and send a non-3GPP registration request 328 , 329 via the 3GPP transceiver 302 to the non-3GPP target CN 305 . The 3GPP radio transceiver 302 and the non-3GPP target CN 305 then conduct authentication procedures 330 . Handover triggers 331 are communicated directly between the 3GPP CN 304 and non-3GPP CN 305 and the 3GPP CN 304 initiates handover with a signal 332 to the 3GPP transceiver 302 . The 3GPP transceiver 302 instructs the non-3GPP radio transceiver 303 to turn ON as signal 333 . With the non-3GPP radio transceiver 303 turned ON, it makes initial contact with the non-3GPP CN 305 and commences radio contact procedures 334 . The 3GPP radio transceiver 302 is turned OFF at 335 and the 3GPP CN 304 and non-3GPP CN 305 exchange handover complete and tunnel release signals 336 . FIG. 4 is a signal diagram for pre-registration procedure for a handover of a WTRU 401 from a non-3GPP handover source 404 to a 3GPP handover target 405 . A WTRU 401 includes a non-3GPP radio transceiver 402 and a 3GPP radio transceiver 403 for communication with a non-3GPP core network (CN) 404 and a 3GPP CN 405 . For simplicity, a dual mode WTRU 401 is shown, however the signaling described herein is valid for a multi-mode WTRU having multiple 3GPP and non-3GPP radio transceivers. While shown as direct signals between the WTRU 401 and CNs 403 , 404 , the signals may be relayed by a NodeB or a base station entity (not shown). The pre-registration begins with the non-3GPP transceiver 402 receiving a 3GPP and non-3GPP measurement list 411 from non-3GPP CN 404 . The measurement list 411 identifies the channel frequencies of candidate handover targets. At 412 , the WTRU 401 stores the list in an internal memory, and for periodically initiating channel measurements. The non-3GPP transceiver 402 sends an initialization signal 413 to the 3GPP transceiver 403 , along with a list of candidate 3GPP handover targets 414 . The 3GPP transceiver 403 is activated and monitors channels and performs measurements at 415 . The 3GPP transceiver 403 sends measurement reports 416 of the monitored channels to the non-3GPP transceiver 402 . The non-3GPP transceiver 402 combines the measurements it made with those made by the 3GPP transceiver 403 , formulates combined measurement reports, and transmits the combined measurement reports 417 to the non-3GPP CN 404 . At 418 , the non-3GPP CN 404 examines the combined measurement reports and selects a handover target system for the WTRU 401 . The non-3GPP CN 404 sends a signal 419 to the target 3GPP CN 405 to initiate a handover direct tunnel, and the target 3GPP CN 405 responds with a tunnel establishment acknowledgment signal 420 . The 3GPP non-CN 404 sends a signal 421 to the non-3GPP transceiver 402 to initiate a handover direct tunnel. This signal 421 may include a 3GPP tunnel endpoint identification (TEID). The non-3GPP transceiver 402 sends the target ID 422 to the 3GPP transceiver 403 . The 3GPP transceiver sends its handover direct tunnel acknowledgment (ACK) 423 to the non-3GPP transceiver 402 , which is then forwarded to the non-3GPP CN 404 as signal 424 . The direct handover tunnel 425 is established between the 3GPP target CN 405 and the 3GPP transceiver 403 . The source non-3GPP CN 404 sends a signal 426 to initiate a 3GPP registration to the non-3GPP transceiver 402 which is then forwarded as signal 427 to the 3GPP transceiver 403 . A 3GPP registration request 428 , 429 is sent from the 3GPP transceiver 403 via the non-3GPP transceiver 402 to the 3GPP target CN 405 . The non-3GPP radio transceiver 402 and the 3GPP target CN 405 then conduct authentication procedures 430 . Handover triggers 431 are communicated directly between the non-3GPP CN 404 and 3GPP CN 405 and the non-3GPP CN 404 initiates handover with a signal 432 to the non-3GPP transceiver 402 . The non-3GPP transceiver 402 instructs the non-3GPP radio transceiver 403 to turn ON with signal 433 . With the 3GPP radio transceiver 403 turned ON, it makes initial contact with the 3GPP CN 405 and commences radio contact procedures 434 . The non-3GPP radio transceiver 402 is turned OFF at 435 and the non-3GPP CN 404 and 3GPP CN 405 exchange handover complete and tunnel release signals 436 . FIGS. 5A , 5 B and 5 C show a signaling diagram of an SIP-based handover of a dual-mode WTRU 501 from a 3GPP source system to a non-3GPP target system. In order to speed the access procedures and hence the handover to the target system, pre-registration and pre-authentication procedures are allowed to be performed by the upper layers in the WTRU 501 of the target technology via the source system, including the IP configuration and connectivity establishment, and the SIP registration and connectivity establishment. In FIG. 5A , the WTRU 501 comprises a 3GPP radio transceiver 502 and a non-3GPP radio transceiver 503 . Also shown are a 3GPP source CN 504 and a non-3GPP target CN 505 . The core networks CN 504 and 505 may be implemented as an access router (AR), access service network (ASN), or authentication, authorization and accounting (AAA) entity. The non-3GPP target system may include for example 3GPP2, WiMAX, or WiFi. As shown in FIG. 5A , SIP connectivity 511 is already established between the 3GPP transceiver 502 and the 3GPP CN 504 and SIP connectivity 512 is already established between the 3GPP CN 504 and the internet protocol (IP) multimedia server (IMS) 506 . The pre-registration begins with the 3GPP transceiver 502 receiving a 3GPP and non-3GPP measurement list 513 from 3GPP CN 504 . The measurement list 513 identifies the channel frequencies of candidate handover targets. At 514 , the WTRU 501 stores the list in an internal memory, and for use in periodically initiating channel measurements. The 3GPP transceiver 502 sends an initialization signal 515 to the non-3GPP transceiver 503 , along with a list of candidate non-3GPP handover targets 516 . At 517 , the non-3GPP transceiver 503 monitors channels and performs measurements. The non-3GPP transceiver 503 sends measurement reports 518 of the monitored channels to the 3GPP transceiver 502 . The 3GPP transceiver 502 combines the measurements it made with those made by the non-3GPP transceiver 503 , formulates combined measurement reports, and transmits the combined measurement reports 519 to the 3GPP CN 504 . At 520 , the 3GPP CN 504 examines the combined measurement reports and selects a handover target system for the WTRU 501 . The 3GPP CN 504 sends a signal 521 ( FIG. 5B ) to the target non-3GPP CN 505 to initiate a handover direct tunnel, and the target non-3GPP CN 505 responds with a tunnel establishment acknowledgment signal 522 . The 3GPP CN 504 sends a signal 523 to the 3GPP transceiver 502 to initiate a handover direct tunnel. This signal 523 may include a non-3GPP tunnel endpoint identification (TEID). The 3GPP transceiver 502 sends the target ID 524 to the non-3GPP transceiver 503 . The non-3GPP transceiver sends its handover direct tunnel acknowledgment (ACK) 525 to the 3GPP transceiver 502 , which is then forwarded to the 3GPP CN 504 as signal 526 . The direct handover tunnel 527 is established between the non-3GPP target CN 505 and the non-3GPP transceiver 503 . The source 3GPP CN 504 sends a signal 528 to initiate a non-3GPP registration to the 3GPP transceiver 502 which is then forwarded as signal 529 to the non-3GPP transceiver 503 . A non-3GPP registration request 529 A is sent from the non-3GPP transceiver 503 to the 3GPP transceiver 502 , and forwarded as signal 530 to the non-3GPP target CN 505 . The registration request 529 A, 530 may include the TEID of the target CN 505 . The 3GPP radio transceiver 502 and the non-3GPP target CN 505 then conduct authentication procedures 531 . Signaling 532 occurs between different protocol stack layers of the 3GPP radio transceiver 502 and the non-3GPP transceiver 503 , where authorization information is exchanged to update the status of the protocol. If successful, then the process of establishing IP connection commences at 533 . The signaling 534 between the WTRU radio transceivers 502 , 503 for establishing IP connectivity is started by tunneling the non-3GPP IP configuration message to the 3GPP protocol stack along crossover path 241 . The 3GPP transceiver 502 establishes non-3GPP IP configuration procedures 535 with the non-3GPP CN 505 . IP configuration messages 536 , 537 are exchanged between the 3GPP transceiver 502 and the non-3GPP transceiver 503 , which may include the IP address of the IP gateway, IP type (e.g., IPv4 or IPv6) and the corresponding quality of signal (QoS) parameters. Additional information may also be sent in the signals 536 , 537 , including a list of Proxy Call State Control Function (P-CSCF) to support the non-3GPP radio transceiver 503 to configure its SIP connectivity. The IP configuration of the non-3GPP transceiver is complete at 538 . For a handover between a 3GPP system and a non-3GPP system, two different IP gateways are involved. One IP gateway is for 3GPP, which is connecting the IMS to the 3GPP transceiver 502 , and the other IP gateway is for establishing the IP connectivity over a non-3GPP system for the non-3GPP transceiver 503 . As shown in FIG. 5C , the SIP based handover signaling continues at 540 , where the non-3GPP transceiver 503 commences SIP registration procedures. Signals 541 - 544 are used to exchange SIP addresses and to perform P-CSCF discovery for connecting the SIP layer in the non-3GPP transceiver 503 to the IMS 506 via the Non-3GPP Core network. Signal 541 is exchanged between the 3GPP transceiver 502 and the non-3GPP transceiver 503 using the crossover path 241 . Signal 542 is sent over the 3GPP air interface from the 3GPP transceiver 602 PHY layer. Signal 543 is exchanged between the 3GPP CN 504 and the non-3GPP CN 505 and signal 544 is exchanged between the non-3GPP CN 505 and the IMS 506 . Acknowledgment signals 545 and 546 are sent between the appropriate protocol layer in the Non-3GPP transceiver 503 and the 3GPP transceiver 502 upon successful SIP registration. With the SIP registration of the non-3GPP transceiver 503 complete at 547 , SIP connectivity 548 and 549 is established between the non-3GPP transceiver 503 and the non-3GPP CN 505 , and between the non-3GPP CN 505 and the IMS 506 , respectively. The non-3GPP CN 505 informs the 3GPP CN 504 that handover is complete with signal 550 . The 3GPP transceiver 502 then performs SIP deregistration and IP release procedures 551 with the IMS 506 . The 3GPP transceiver 502 receives signal 552 from the 3GPP CN 504 indicating a handover complete, a radio switch OFF command and a release 3GPP radio access bearer (RAB) command. The 3GPP transceiver 502 informs the non-3GPP transceiver 503 that the handover is complete with signal 553 , and the non-3GPP radio transceiver 503 is activated ON. At 554 , the non-3GPP transceiver 503 commences non-3GPP RF connectivity procedures with the non-3GPP CN 505 . FIGS. 6A , 6 B and 6 C show a signaling diagram of an SIP-based handover of a dual-mode WTRU 601 from a non-3GPP source system to a 3GPP target system. In order to speed the access procedures and hence the handover to the target system, pre-registration and pre-authentication procedures are allowed to be performed by the upper layers in the WTRU 601 of the target technology via the source system, including the IP configuration and the SIP registration procedures. In FIG. 6A , the WTRU 601 comprises a 3GPP radio transceiver 602 and a non-3GPP radio transceiver 603 . Also shown are a 3GPP target CN 604 and a non-3GPP source CN 605 . The core networks CN 604 and 605 may be implemented as an access router (AR), access service network (ASN), or authentication, authorization and accounting (AAA) entity. The non-3GPP target system may include for example 3GPP2, WiMAX, or WiFi. As shown in FIG. 6A , SIP connectivity 611 is already established between the non-3GPP transceiver 603 and the non-3GPP CN 605 and SIP connectivity 612 is already established between the non-3GPP CN 604 and the IP multimedia server (IMS) 606 . The pre-registration begins with the 3GPP transceiver 603 receiving a 3GPP and non-3GPP measurement list 613 from non-3GPP CN 605 . The measurement list 613 identifies the channel frequencies of candidate handover targets. At 614 , the WTRU 601 stores the list in an internal memory, and for use in periodically initiating channel measurements. The non-3GPP transceiver 603 sends an initialization signal 615 to the 3GPP transceiver 602 , along with a list of candidate 3GPP handover targets 616 . At 617 , the 3GPP transceiver 602 monitors channels and performs measurements. The 3GPP transceiver 602 sends measurement reports 618 of the monitored channels to the non-3GPP transceiver 603 . The non-3GPP transceiver 603 combines the measurements it made with those made by the 3GPP transceiver 603 , formulates combined measurement reports, and transmits the combined measurement reports 619 to the non-3GPP CN 605 . At 620 , the non-3GPP CN 605 examines the combined measurement reports and selects a handover target system for the WTRU 601 . The non-3GPP CN 605 sends a signal 621 ( FIG. 6B ) to the target 3GPP CN 604 to initiate a handover direct tunnel, and the target 3GPP CN 604 responds with a tunnel establishment acknowledgment signal 622 . The non-3GPP CN 605 sends a signal 623 to the non-3GPP transceiver 603 to initiate a handover direct tunnel This signal 623 may include a 3GPP tunnel endpoint identification (TEID). The non-3GPP transceiver 603 sends the target ID 624 to the 3GPP transceiver 602 . The 3GPP transceiver 602 sends its handover direct tunnel acknowledgment (ACK) 625 to the non-3GPP transceiver 603 , which is then forwarded to the non-3GPP CN 605 as signal 626 . The direct handover tunnel 627 is established between the 3GPP target CN 604 and the 3GPP transceiver 602 . The source non-3GPP CN 605 sends a signal 628 to initiate a 3GPP registration to the non-3GPP transceiver 603 which is then forwarded as signal 629 to the 3GPP transceiver 602 . A 3GPP registration request 629 A is sent from the 3GPP transceiver 602 to the non-3GPP transceiver 603 and forwarded as signal 630 to the 3GPP target CN 604 . The registration request 629 A, 630 may include the TEID of the target CN 604 . The non-3GPP radio transceiver 603 and the 3GPP target CN 604 then conduct authentication procedures 631 . Signaling 632 occurs between different protocol stack layers of the 3GPP radio transceiver 602 and the non-3GPP transceiver 603 , where authorization information is exchanged to update the status of the protocol. If successful, then the process of establishing IP connection commences at 633 . The signaling 634 for IP connectivity is started by tunneling the 3GPP IP configuration message to the non-3GPP protocol stack along crossover path 231 . The non-3GPP transceiver 603 establishes 3GPP IP configuration procedures 635 with the 3GPP CN 604 . IP configuration messages 636 , 637 are exchanged between the 3GPP transceiver 602 and the non-3GPP transceiver 603 , which may include the IP address of the IP gateway, IP type (e.g., IPv4 or IPv6) and the corresponding quality of signal (QoS) parameters. Additional information may also be sent in the signals 636 , 637 , including a list of Proxy Call State Control Function (P-CSCF) to support the 3GPP radio transceiver 602 to configure its SIP connectivity. The IP configuration of the non-3GPP transceiver is complete at 638 . As shown in FIG. 6C , the SIP based handover signaling continues at 640 , where the 3GPP transceiver 602 commences SIP registration procedures. Signals 641 - 644 are used to exchange SIP addresses and to perform P-CSCF discovery for connecting the SIP layer in the 3GPP transceiver 602 to the IMS 606 via the 3GPP core network 604 . Signal 641 is exchanged between the 3GPP transceiver 602 upper layers and the non-3GPP transceiver 603 PHY layer using the crossover path 231 . Signal 642 is sent over the non-3GPP air interface from the non-3GPP transceiver 603 PHY layer to the non-3GPP CN 605 . Signal 643 is exchanged between the non-3GPP CN 605 and the 3GPP CN 604 and signal 644 is exchanged between the 3GPP CN 604 and the IMS 606 . Acknowledgment signals 645 and 646 are sent between the appropriate protocol layer in the Non-3GPP transceiver 603 and the 3GPP transceiver 602 upon successful SIP registration. With the SIP registration of the 3GPP transceiver 602 complete at 647 , SIP connectivity 648 and 649 is established between the 3GPP transceiver 602 and the 3GPP CN 604 , and between the 3GPP CN 604 and the IMS 606 , respectively. The 3GPP CN 604 informs the non-3GPP CN 605 that handover is complete with signal 650 . The non-3GPP transceiver 603 then performs SIP deregistration and IP release procedures 651 with the IMS 606 . The non-3GPP transceiver 603 receives signal 652 from the non-3GPP CN 605 indicating a handover complete, a radio switch OFF command and a release non-3GPP radio access bearer (RAB) command. The non-3GPP transceiver 603 informs the 3GPP transceiver 602 that the handover is complete with signal 653 , and the 3GPP radio transceiver 602 is activated ON. At 654 , the 3GPP transceiver 602 commences 3GPP RF connectivity procedures with the 3GPP CN 604 . FIGS. 7 and 8 show systematic block diagrams for the SIP based handover method described above. In FIG. 7 , communication links for a handover of WTRU 201 from a 3GPP source system to a non-3GPP target system is shown sequentially by signal paths 701 , 702 and 703 . Initially, the WTRU 201 is connected to the 3GPP source system on signal path 701 via an IMS 711 , a 3GPP CN 721 , and a 3GPP eNodeB (eNB) 722 that is in a wireless communication with the 3GPP PHY layer 223 . In order to prepare for handover to a non-3GPP target, a make-before-break path 702 is established to the non-3GPP transceiver protocol stack (i.e., SIP application layer 210 , SM and MM layer 211 , RRC and MAC layer 212 ) via the crossover path 241 between the 3GPP PHY layer 223 and non-3GPP RRC and MAC layer 212 . The communication path 702 allows the non-3GPP protocol stack to receive target system information via the active 3GPP source system using the 3GPP eNB 722 , the 3GPP CN 721 , which exchanges information with the target non-3GPP CN 731 , gateway (GW) 712 and IMS 711 . The communication path 702 is established when the WTRU 201 receives instructions from the source 3GPP system to start the access procedures toward the target system and to perform the sequence of access specific procedures (e.g., Attach, IP configuration, and SIP Registration). Upon successful completion of the access specific procedures and the SIP registration, the SIP connectivity is established as shown by communication path 703 between the non-3GPP protocol stack (i.e. layers 210 , 211 , 212 and PHY layer 213 ) and the non-3GPP radio access network (RAN) 732 , the non-3GPP CN 731 , the gateway (GW) 712 and IMS 711 . The WTRU 201 receives instructions from the 3GPP source system to switch (or handover) to the non-3GPP target system and turn off the radio on the 3GPP source system (i.e., turn OFF the 3GPP transceiver of WTRU 201 ), which terminates the communication links 701 and 702 . This ensures that the SIP based session is established to the non-3GPP target system. A WTRU controller 251 executes the access procedures and the handover procedures responsive to the received instructions from the 3GPP source system. In FIG. 8 , communication links for a handover of WTRU 201 from a non-3GPP source system to a 3GPP target system is shown sequentially by signal paths 801 , 802 and 803 . Initially, the WTRU 201 is connected to the non-3GPP source system on signal path 801 via an IMS 711 , a gateway (GW) 712 , a non-3GPP CN 731 , and a non-3GPP RAN 732 that is in a wireless communication with the non-3GPP PHY layer 213 . In order to prepare for handover to a 3GPP target system, a make-before-break path 802 is established between 3GPP target system to the 3GPP transceiver protocol stack (i.e., SIP application layer 220 , SM and MM layer 221 , RRC and MAC layer 222 ) via the crossover path 231 between the non-3GPP PHY layer 213 and non-3GPP RRC and MAC layer 222 . The communication path 802 allows the 3GPP protocol stack to receive target system information via the active non-3GPP source system using the non-3GPP RAN 732 , the non-3GPP CN 731 , which exchanges information with the target 3GPP CN 721 and IMS 711 . The communication path 802 is established when the WTRU 201 receives instructions from the source non-3GPP system to start the access procedures toward the 3GPP target system and to perform the sequence of access specific procedures (e.g., Attach, IP configuration, and SIP Registration). Upon successful completion of the access specific procedures and the SIP registration, the SIP connectivity is established as shown by communication path 803 between the 3GPP protocol stack (i.e. layers 220 , 221 , 222 and PHY layer 223 ) and the non-3GPP RAN 732 , followed by the non-3GPP CN 731 , the 3GPP CN 721 and IMS 711 . The WTRU 201 receives instructions from the 3GPP source system to switch (or handover) to the non-3GPP target system and turn off the radio on the 3GPP source system (i.e., turn OFF the non-3GPP transceiver of WTRU 201 ), which terminates the communication links 801 and 802 . This ensures that the SIP based session is established to the non-3GPP target system. A WTRU controller 251 executes the access procedures and the handover procedures responsive to the received instructions from the 3GPP source system. Although the features and elements of the present invention are described in the preferred embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the preferred embodiments or in various combinations with or without other features and elements of the present invention. The methods or flow charts provided in the present invention may be implemented in a computer program, software, or firmware tangibly embodied in a computer-readable storage medium for execution by a general purpose computer or a processor. Examples of computer-readable storage mediums include a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks, and digital versatile disks (DVDs). Suitable processors include, by way of example, a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits, any other type of integrated circuit (IC), and/or a state machine. A processor in association with software may be used to implement a radio frequency transceiver for use in a wireless transmit receive unit (WTRU), user equipment (UE), terminal, base station, radio network controller (RNC), or any host computer. The WTRU may be used in conjunction with modules, implemented in hardware and/or software, such as a camera, a video camera module, a videophone, a speakerphone, a vibration device, a speaker, a microphone, a television transceiver, a hands free headset, a keyboard, a Bluetooth® module, a frequency modulated (FM) radio unit, a liquid crystal display (LCD) display unit, an organic light-emitting diode (OLED) display unit, a digital music player, a media player, a video game player module, an Internet browser, and/or any wireless local area network (WLAN) module.
A method and apparatus for session continuity using pre-registration tunneling procedure are disclosed. For session continuity, a tunnel is established between a multi-mode wireless transmit/receive unit (WTRU) and a core network of a target system via a source system while the WTRU is still connected with the source system. An access procedure is performed toward the target system using the tunnel. A handover is the performed from the source system to the target system once the access procedure is complete. The access procedure includes session initiation protocol (SIP) registration, authentication of the WTRU at the target system, and internet protocol (IP) configuration. The handover may be from a third generation partnership project (3GPP) system to a non-3GPP system, or vice versa.
Condense the core contents of the given document.
[ "CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser.", "No. 12/169,751, filed Jul. 9, 2008;", "which claims the benefit of U.S. Provisional Patent Application Nos. 60/948,587, filed Jul. 9, 2007, and 60/949,085, filed Jul. 11, 2007, the contents of which are hereby incorporated by reference herein in their entirety.", "FIELD OF INVENTION The present application is related to wireless communication systems.", "BACKGROUND A dual-mode or multi-mode wireless transmit/receive unit has dual or multiple radio transceivers, each designed to communicate on a particular radio access technology (RAT), such as 3rd Generation Partnership Project (3GPP) and non-3GPP systems.", "The handover process between 3GPP and non-3GPP systems may be slow due to the nature of the system configurations and operations.", "One problem occurs when a WTRU moves from one system to another as the WTRU is required to register and authenticate in the other system.", "A similar problem exists for session initiation protocol (SIP)-based Session Continuity processes between 3GPP and non-3GPP systems.", "When moving from one system to the other, the WTRU is required to register and authenticate in the other system before registering with internet protocol (IP) multimedia subsystem (IMS).", "Another problem may occur due to the 3GPP prohibition against simultaneous radio transceiver operation.", "A single WTRU cannot have a 3GPP radio transceiver and a non-3GPP radio transceiver active at the same time.", "In such cases, dual-mode or multi-mode radio transceivers need sophisticated control of the radio switching.", "SUMMARY The present invention is related to a method and apparatus for session continuity using pre-registration tunneling procedure.", "For session continuity, a tunnel is established between a wireless transmit/receive unit (WTRU) and a core network of a target system via a source system while the WTRU is still connected with the source system.", "An access procedure is performed toward the target system using the tunnel.", "A handover is performed from the source system to the target system once the access procedure is complete.", "For session initiation protocol (SIP) based handover, the access procedure includes SIP registration, authentication of the WTRU at the target system, and internet protocol (IP) configuration.", "The handover may be from a third generation partnership project (3GPP) system to a non-3GPP system, or vice versa.", "BRIEF DESCRIPTION OF THE DRAWINGS A more detailed understanding of the invention may be had from the following description of a preferred embodiment, given by way of example and to be understood in conjunction with the accompanying drawings wherein: FIG. 1 shows a block diagram of dual protocol stack configuration in a dual mode wireless transmit/receive unit (WTRU) in accordance with a first embodiment;", "FIG. 2 shows a block diagram of a dual protocol stack configuration in a dual mode WTRU supporting pre-registration SIP-based session continuity in accordance with a second embodiment;", "FIGS. 3A and 3B show a signal diagram of a pre-registration procedure for a 3GPP to non-3GPP handover in accordance with the first embodiment;", "FIGS. 4A and 4B show a signal diagram of a pre-registration procedure for a non-3GPP to 3GPP handover in accordance with the first embodiment;", "FIGS. 5A , 5 B and 5 C show a signaling diagram of pre-registration procedures for 3GPP to non-3GPP handover in accordance with the second embodiment;", "FIGS. 6A , 6 B and 6 C show a signaling diagram of pre-registration procedures for non-3GPP to 3GPP handover in accordance with the second embodiment;", "FIG. 7 shows dual stack operation in a multi-mode WTRU supporting pre-registration SIP-based session continuity for 3GPP to non-3GPP handover in accordance with the second embodiment;", "and FIG. 8 shows dual stack operation in a multi-mode WTRU supporting pre-registration SIP-based session continuity for non-3GPP to 3GPP handover in accordance with the second embodiment.", "DETAILED DESCRIPTION When referred to hereafter, the terminology “WTRU”", "includes but is not limited to a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, a cellular telephone, a personal digital assistant (PDA), a computer, or any other type of user device capable of operating in a wireless environment.", "When referred to hereafter, the terminology “base station”", "includes but is not limited to a Node-B, a site controller, an access point (AP), or any other type of interfacing device capable of operating in a wireless environment.", "By way of reference, as a WTRU moves from a system A to a system B, system A is defined as the handover source and system B is defined as the handover target.", "One mechanism to speed access procedures to a target system is to allow pre-registration and pre-authentication procedures to be performed by upper layers in a WTRU via the source system.", "The source system may identify the target system, establish a tunnel between the WTRU and the core target network, (e.g., Autonomous Registration (AR) or Access, Authentication and Accounting (AAA)), and instruct the WTRU to start access procedures for the target network.", "Upon successful completion of the access procedure, the source network may instruct the WTRU to switch, or handover, to the target network and turn off the radio connected to the source network.", "FIG. 1 is a block diagram of dual protocol layer stack in a dual mode WTRU 101 supporting pre-registration tunneling in accordance with a first embodiment.", "As shown in FIG. 1 , the WTRU 101 includes a non-3GPP protocol layer stack comprising an application layer 110 , a mobility management (MM) layer 111 , a radio resource control (RRC) and media access control (MAC) layer 112 , and a physical (PHY) layer 113 .", "The application layer 110 is coupled to the MM layer 111 by path 115 .", "The MM layer 111 is coupled to the RRC/MAC layer 112 by path 116 .", "Path 117 couples the RRC/MAC layer 112 to the PHY layer 113 .", "Similarly, a 3GPP protocol layer stack comprises an application layer 120 , a multimedia (MM) layer 121 , a radio resource control (RRC) and media access control (MAC) layer 122 , and a physical (PHY) layer 123 .", "The application layer 120 is coupled to the MM layer 121 by path 125 .", "The MM layer 121 is coupled to the RRC/MAC layer 122 by path 126 .", "Path 127 couples the RRC/MAC layer 122 to the PHY layer 123 .", "The dual protocol layer stack is further configured to include a path 141 , which cross connects the non-3GPP PHY layer 113 to the 3GPP RRC/MAC layer 122 .", "A path 131 couples the 3GPP PHY layer 123 to the non-3GPP RRC/MAC layer 112 .", "These paths 131 and 141 are used to establish tunneling between 3GPP and non-3GPP systems to facilitate 3GPP to non-3GPP handover.", "A controller 151 controls the signaling for handover and access procedures executed at the protocol stack layers shown in FIG. 1 .", "FIG. 2 is a block diagram of dual protocol layer stack in a dual mode WTRU 201 supporting pre-registration tunneling in accordance with a second embodiment.", "As shown in FIG. 2 , the WTRU 201 includes a non-3GPP protocol layer stack comprising an application layer 210 , a session management (SM) and mobility management (MM) layer 211 , a radio resource control (RRC) and media access control (MAC) layer 212 , and a physical (PHY) layer 213 .", "The application layer 210 is coupled to the SM and MM layer 211 by path 215 .", "The SM and MM layer 211 is coupled to the RRC/MAC layer 212 by path 216 .", "Path 217 couples the RRC/MAC layer 212 to the PHY layer 213 .", "Similarly, a 3GPP protocol layer stack comprises an application layer 220 , a SM and MM layer 221 , a radio resource control (RRC) and media access control (MAC) layer 222 , and a physical (PHY) layer 223 .", "The application layer 220 is coupled to the SM and MM layer 221 by path 225 .", "The SM and MM layer 221 is coupled to the RRC/MAC layer 222 by path 226 .", "Path 227 couples the RRC/MAC layer 222 to the PHY layer 223 .", "The dual protocol layer stack is further configured to include a path 241 , which cross connects the non-3GPP PHY layer 213 to the 3GPP RRC/MAC layer 222 .", "A path 231 couples the 3GPP PHY layer 223 to the non-3GPP RRC/MAC layer 212 .", "These paths 231 and 241 are used to establish tunneling between 3GPP and non-3GPP systems to facilitate 3GPP to non-3GPP handover.", "A controller 251 controls the signaling for handover and access procedures executed at the protocol stack layers shown in FIG. 2 .", "FIGS. 3A and 3B show a signal diagram for pre-registration procedure for a handover of a WTRU 301 from a 3GPP handover source 304 to a non-3GPP handover target 305 .", "A WTRU 301 includes a 3GPP radio transceiver 302 and a non-3GPP radio transceiver 303 for communication with a 3GPP core network (CN) 304 and a non-3GPP CN 305 .", "For simplicity, a dual mode WTRU 301 is shown, however the signaling described herein is valid for a multi-mode WTRU having multiple 3GPP and non-3GPP radio transceivers.", "While shown as direct signals from the WTRU 301 and CNs 303 , 304 , the signals may be relayed by a NodeB or a base station entity (not shown).", "The pre-registration begins with the 3GPP transceiver 302 receiving a 3GPP and non-3GPP measurement list 311 from 3GPP CN 304 .", "The measurement list 311 identifies the channel frequencies of candidate handover targets.", "At 312 , the WTRU 301 stores the list in an internal memory, and for periodically initiating channel measurements.", "The 3GPP transceiver 302 sends an initialization signal 313 to the non-3GPP transceiver 303 , along with a list of candidate non-3GPP handover targets 314 .", "At 315 , the non-3GPP transceiver 303 is activated for a period in order to perform measurement procedures, in which it monitors channels and performs measurements.", "The non-3GPP transceiver 303 sends measurement reports 316 of the monitored channels to the 3GPP transceiver 302 .", "When measurement procedures by the non-3GPP transceiver 303 are completed, it may be deactivated.", "At 317 , the 3GPP transceiver 302 combines the measurements it made with those made by the non-3GPP transceiver 303 , formulates combined measurement reports, and transmits the combined measurement reports to the 3GPP CN 304 .", "At 318 , the 3GPP CN 304 examines the combined measurement reports and handover (HO) criteria, and selects a handover target system for the WTRU 301 .", "The 3GPP CN 304 sends a signal 319 to the target non-3GPP CN 305 to initiate a handover direct tunnel, and the target non-3GPP CN 305 responds with a tunnel establishment acknowledgment signal 320 .", "The 3GPP CN 304 sends a signal 321 to the 3GPP transceiver 302 to initiate a handover direct tunnel.", "This signal 321 may include a non-3GPP tunnel endpoint identification (TEID).", "The 3GPP transceiver 302 sends the target ID 322 to the non-3GPP transceiver 303 .", "The non-3GPP transceiver sends its handover direct tunnel acknowledgment (ACK) 323 to the 3GPP transceiver 302 , which is then forwarded to the 3GPP CN 304 as signal 324 .", "The direct handover tunnel 325 is established between the non-3GPP target CN 305 and the non-3GPP transceiver 303 .", "The source 3GPP CN 304 sends a signal 326 to initiate a non-3GPP registration to the 3GPP transceiver 302 which is then forwarded as signal 327 to the non-3GPP transceiver 303 .", "The upper layers of the non-3GPP transceiver 303 perform pre-registration pre-authentication procedures, and send a non-3GPP registration request 328 , 329 via the 3GPP transceiver 302 to the non-3GPP target CN 305 .", "The 3GPP radio transceiver 302 and the non-3GPP target CN 305 then conduct authentication procedures 330 .", "Handover triggers 331 are communicated directly between the 3GPP CN 304 and non-3GPP CN 305 and the 3GPP CN 304 initiates handover with a signal 332 to the 3GPP transceiver 302 .", "The 3GPP transceiver 302 instructs the non-3GPP radio transceiver 303 to turn ON as signal 333 .", "With the non-3GPP radio transceiver 303 turned ON, it makes initial contact with the non-3GPP CN 305 and commences radio contact procedures 334 .", "The 3GPP radio transceiver 302 is turned OFF at 335 and the 3GPP CN 304 and non-3GPP CN 305 exchange handover complete and tunnel release signals 336 .", "FIG. 4 is a signal diagram for pre-registration procedure for a handover of a WTRU 401 from a non-3GPP handover source 404 to a 3GPP handover target 405 .", "A WTRU 401 includes a non-3GPP radio transceiver 402 and a 3GPP radio transceiver 403 for communication with a non-3GPP core network (CN) 404 and a 3GPP CN 405 .", "For simplicity, a dual mode WTRU 401 is shown, however the signaling described herein is valid for a multi-mode WTRU having multiple 3GPP and non-3GPP radio transceivers.", "While shown as direct signals between the WTRU 401 and CNs 403 , 404 , the signals may be relayed by a NodeB or a base station entity (not shown).", "The pre-registration begins with the non-3GPP transceiver 402 receiving a 3GPP and non-3GPP measurement list 411 from non-3GPP CN 404 .", "The measurement list 411 identifies the channel frequencies of candidate handover targets.", "At 412 , the WTRU 401 stores the list in an internal memory, and for periodically initiating channel measurements.", "The non-3GPP transceiver 402 sends an initialization signal 413 to the 3GPP transceiver 403 , along with a list of candidate 3GPP handover targets 414 .", "The 3GPP transceiver 403 is activated and monitors channels and performs measurements at 415 .", "The 3GPP transceiver 403 sends measurement reports 416 of the monitored channels to the non-3GPP transceiver 402 .", "The non-3GPP transceiver 402 combines the measurements it made with those made by the 3GPP transceiver 403 , formulates combined measurement reports, and transmits the combined measurement reports 417 to the non-3GPP CN 404 .", "At 418 , the non-3GPP CN 404 examines the combined measurement reports and selects a handover target system for the WTRU 401 .", "The non-3GPP CN 404 sends a signal 419 to the target 3GPP CN 405 to initiate a handover direct tunnel, and the target 3GPP CN 405 responds with a tunnel establishment acknowledgment signal 420 .", "The 3GPP non-CN 404 sends a signal 421 to the non-3GPP transceiver 402 to initiate a handover direct tunnel.", "This signal 421 may include a 3GPP tunnel endpoint identification (TEID).", "The non-3GPP transceiver 402 sends the target ID 422 to the 3GPP transceiver 403 .", "The 3GPP transceiver sends its handover direct tunnel acknowledgment (ACK) 423 to the non-3GPP transceiver 402 , which is then forwarded to the non-3GPP CN 404 as signal 424 .", "The direct handover tunnel 425 is established between the 3GPP target CN 405 and the 3GPP transceiver 403 .", "The source non-3GPP CN 404 sends a signal 426 to initiate a 3GPP registration to the non-3GPP transceiver 402 which is then forwarded as signal 427 to the 3GPP transceiver 403 .", "A 3GPP registration request 428 , 429 is sent from the 3GPP transceiver 403 via the non-3GPP transceiver 402 to the 3GPP target CN 405 .", "The non-3GPP radio transceiver 402 and the 3GPP target CN 405 then conduct authentication procedures 430 .", "Handover triggers 431 are communicated directly between the non-3GPP CN 404 and 3GPP CN 405 and the non-3GPP CN 404 initiates handover with a signal 432 to the non-3GPP transceiver 402 .", "The non-3GPP transceiver 402 instructs the non-3GPP radio transceiver 403 to turn ON with signal 433 .", "With the 3GPP radio transceiver 403 turned ON, it makes initial contact with the 3GPP CN 405 and commences radio contact procedures 434 .", "The non-3GPP radio transceiver 402 is turned OFF at 435 and the non-3GPP CN 404 and 3GPP CN 405 exchange handover complete and tunnel release signals 436 .", "FIGS. 5A , 5 B and 5 C show a signaling diagram of an SIP-based handover of a dual-mode WTRU 501 from a 3GPP source system to a non-3GPP target system.", "In order to speed the access procedures and hence the handover to the target system, pre-registration and pre-authentication procedures are allowed to be performed by the upper layers in the WTRU 501 of the target technology via the source system, including the IP configuration and connectivity establishment, and the SIP registration and connectivity establishment.", "In FIG. 5A , the WTRU 501 comprises a 3GPP radio transceiver 502 and a non-3GPP radio transceiver 503 .", "Also shown are a 3GPP source CN 504 and a non-3GPP target CN 505 .", "The core networks CN 504 and 505 may be implemented as an access router (AR), access service network (ASN), or authentication, authorization and accounting (AAA) entity.", "The non-3GPP target system may include for example 3GPP2, WiMAX, or WiFi.", "As shown in FIG. 5A , SIP connectivity 511 is already established between the 3GPP transceiver 502 and the 3GPP CN 504 and SIP connectivity 512 is already established between the 3GPP CN 504 and the internet protocol (IP) multimedia server (IMS) 506 .", "The pre-registration begins with the 3GPP transceiver 502 receiving a 3GPP and non-3GPP measurement list 513 from 3GPP CN 504 .", "The measurement list 513 identifies the channel frequencies of candidate handover targets.", "At 514 , the WTRU 501 stores the list in an internal memory, and for use in periodically initiating channel measurements.", "The 3GPP transceiver 502 sends an initialization signal 515 to the non-3GPP transceiver 503 , along with a list of candidate non-3GPP handover targets 516 .", "At 517 , the non-3GPP transceiver 503 monitors channels and performs measurements.", "The non-3GPP transceiver 503 sends measurement reports 518 of the monitored channels to the 3GPP transceiver 502 .", "The 3GPP transceiver 502 combines the measurements it made with those made by the non-3GPP transceiver 503 , formulates combined measurement reports, and transmits the combined measurement reports 519 to the 3GPP CN 504 .", "At 520 , the 3GPP CN 504 examines the combined measurement reports and selects a handover target system for the WTRU 501 .", "The 3GPP CN 504 sends a signal 521 ( FIG. 5B ) to the target non-3GPP CN 505 to initiate a handover direct tunnel, and the target non-3GPP CN 505 responds with a tunnel establishment acknowledgment signal 522 .", "The 3GPP CN 504 sends a signal 523 to the 3GPP transceiver 502 to initiate a handover direct tunnel.", "This signal 523 may include a non-3GPP tunnel endpoint identification (TEID).", "The 3GPP transceiver 502 sends the target ID 524 to the non-3GPP transceiver 503 .", "The non-3GPP transceiver sends its handover direct tunnel acknowledgment (ACK) 525 to the 3GPP transceiver 502 , which is then forwarded to the 3GPP CN 504 as signal 526 .", "The direct handover tunnel 527 is established between the non-3GPP target CN 505 and the non-3GPP transceiver 503 .", "The source 3GPP CN 504 sends a signal 528 to initiate a non-3GPP registration to the 3GPP transceiver 502 which is then forwarded as signal 529 to the non-3GPP transceiver 503 .", "A non-3GPP registration request 529 A is sent from the non-3GPP transceiver 503 to the 3GPP transceiver 502 , and forwarded as signal 530 to the non-3GPP target CN 505 .", "The registration request 529 A, 530 may include the TEID of the target CN 505 .", "The 3GPP radio transceiver 502 and the non-3GPP target CN 505 then conduct authentication procedures 531 .", "Signaling 532 occurs between different protocol stack layers of the 3GPP radio transceiver 502 and the non-3GPP transceiver 503 , where authorization information is exchanged to update the status of the protocol.", "If successful, then the process of establishing IP connection commences at 533 .", "The signaling 534 between the WTRU radio transceivers 502 , 503 for establishing IP connectivity is started by tunneling the non-3GPP IP configuration message to the 3GPP protocol stack along crossover path 241 .", "The 3GPP transceiver 502 establishes non-3GPP IP configuration procedures 535 with the non-3GPP CN 505 .", "IP configuration messages 536 , 537 are exchanged between the 3GPP transceiver 502 and the non-3GPP transceiver 503 , which may include the IP address of the IP gateway, IP type (e.g., IPv4 or IPv6) and the corresponding quality of signal (QoS) parameters.", "Additional information may also be sent in the signals 536 , 537 , including a list of Proxy Call State Control Function (P-CSCF) to support the non-3GPP radio transceiver 503 to configure its SIP connectivity.", "The IP configuration of the non-3GPP transceiver is complete at 538 .", "For a handover between a 3GPP system and a non-3GPP system, two different IP gateways are involved.", "One IP gateway is for 3GPP, which is connecting the IMS to the 3GPP transceiver 502 , and the other IP gateway is for establishing the IP connectivity over a non-3GPP system for the non-3GPP transceiver 503 .", "As shown in FIG. 5C , the SIP based handover signaling continues at 540 , where the non-3GPP transceiver 503 commences SIP registration procedures.", "Signals 541 - 544 are used to exchange SIP addresses and to perform P-CSCF discovery for connecting the SIP layer in the non-3GPP transceiver 503 to the IMS 506 via the Non-3GPP Core network.", "Signal 541 is exchanged between the 3GPP transceiver 502 and the non-3GPP transceiver 503 using the crossover path 241 .", "Signal 542 is sent over the 3GPP air interface from the 3GPP transceiver 602 PHY layer.", "Signal 543 is exchanged between the 3GPP CN 504 and the non-3GPP CN 505 and signal 544 is exchanged between the non-3GPP CN 505 and the IMS 506 .", "Acknowledgment signals 545 and 546 are sent between the appropriate protocol layer in the Non-3GPP transceiver 503 and the 3GPP transceiver 502 upon successful SIP registration.", "With the SIP registration of the non-3GPP transceiver 503 complete at 547 , SIP connectivity 548 and 549 is established between the non-3GPP transceiver 503 and the non-3GPP CN 505 , and between the non-3GPP CN 505 and the IMS 506 , respectively.", "The non-3GPP CN 505 informs the 3GPP CN 504 that handover is complete with signal 550 .", "The 3GPP transceiver 502 then performs SIP deregistration and IP release procedures 551 with the IMS 506 .", "The 3GPP transceiver 502 receives signal 552 from the 3GPP CN 504 indicating a handover complete, a radio switch OFF command and a release 3GPP radio access bearer (RAB) command.", "The 3GPP transceiver 502 informs the non-3GPP transceiver 503 that the handover is complete with signal 553 , and the non-3GPP radio transceiver 503 is activated ON.", "At 554 , the non-3GPP transceiver 503 commences non-3GPP RF connectivity procedures with the non-3GPP CN 505 .", "FIGS. 6A , 6 B and 6 C show a signaling diagram of an SIP-based handover of a dual-mode WTRU 601 from a non-3GPP source system to a 3GPP target system.", "In order to speed the access procedures and hence the handover to the target system, pre-registration and pre-authentication procedures are allowed to be performed by the upper layers in the WTRU 601 of the target technology via the source system, including the IP configuration and the SIP registration procedures.", "In FIG. 6A , the WTRU 601 comprises a 3GPP radio transceiver 602 and a non-3GPP radio transceiver 603 .", "Also shown are a 3GPP target CN 604 and a non-3GPP source CN 605 .", "The core networks CN 604 and 605 may be implemented as an access router (AR), access service network (ASN), or authentication, authorization and accounting (AAA) entity.", "The non-3GPP target system may include for example 3GPP2, WiMAX, or WiFi.", "As shown in FIG. 6A , SIP connectivity 611 is already established between the non-3GPP transceiver 603 and the non-3GPP CN 605 and SIP connectivity 612 is already established between the non-3GPP CN 604 and the IP multimedia server (IMS) 606 .", "The pre-registration begins with the 3GPP transceiver 603 receiving a 3GPP and non-3GPP measurement list 613 from non-3GPP CN 605 .", "The measurement list 613 identifies the channel frequencies of candidate handover targets.", "At 614 , the WTRU 601 stores the list in an internal memory, and for use in periodically initiating channel measurements.", "The non-3GPP transceiver 603 sends an initialization signal 615 to the 3GPP transceiver 602 , along with a list of candidate 3GPP handover targets 616 .", "At 617 , the 3GPP transceiver 602 monitors channels and performs measurements.", "The 3GPP transceiver 602 sends measurement reports 618 of the monitored channels to the non-3GPP transceiver 603 .", "The non-3GPP transceiver 603 combines the measurements it made with those made by the 3GPP transceiver 603 , formulates combined measurement reports, and transmits the combined measurement reports 619 to the non-3GPP CN 605 .", "At 620 , the non-3GPP CN 605 examines the combined measurement reports and selects a handover target system for the WTRU 601 .", "The non-3GPP CN 605 sends a signal 621 ( FIG. 6B ) to the target 3GPP CN 604 to initiate a handover direct tunnel, and the target 3GPP CN 604 responds with a tunnel establishment acknowledgment signal 622 .", "The non-3GPP CN 605 sends a signal 623 to the non-3GPP transceiver 603 to initiate a handover direct tunnel This signal 623 may include a 3GPP tunnel endpoint identification (TEID).", "The non-3GPP transceiver 603 sends the target ID 624 to the 3GPP transceiver 602 .", "The 3GPP transceiver 602 sends its handover direct tunnel acknowledgment (ACK) 625 to the non-3GPP transceiver 603 , which is then forwarded to the non-3GPP CN 605 as signal 626 .", "The direct handover tunnel 627 is established between the 3GPP target CN 604 and the 3GPP transceiver 602 .", "The source non-3GPP CN 605 sends a signal 628 to initiate a 3GPP registration to the non-3GPP transceiver 603 which is then forwarded as signal 629 to the 3GPP transceiver 602 .", "A 3GPP registration request 629 A is sent from the 3GPP transceiver 602 to the non-3GPP transceiver 603 and forwarded as signal 630 to the 3GPP target CN 604 .", "The registration request 629 A, 630 may include the TEID of the target CN 604 .", "The non-3GPP radio transceiver 603 and the 3GPP target CN 604 then conduct authentication procedures 631 .", "Signaling 632 occurs between different protocol stack layers of the 3GPP radio transceiver 602 and the non-3GPP transceiver 603 , where authorization information is exchanged to update the status of the protocol.", "If successful, then the process of establishing IP connection commences at 633 .", "The signaling 634 for IP connectivity is started by tunneling the 3GPP IP configuration message to the non-3GPP protocol stack along crossover path 231 .", "The non-3GPP transceiver 603 establishes 3GPP IP configuration procedures 635 with the 3GPP CN 604 .", "IP configuration messages 636 , 637 are exchanged between the 3GPP transceiver 602 and the non-3GPP transceiver 603 , which may include the IP address of the IP gateway, IP type (e.g., IPv4 or IPv6) and the corresponding quality of signal (QoS) parameters.", "Additional information may also be sent in the signals 636 , 637 , including a list of Proxy Call State Control Function (P-CSCF) to support the 3GPP radio transceiver 602 to configure its SIP connectivity.", "The IP configuration of the non-3GPP transceiver is complete at 638 .", "As shown in FIG. 6C , the SIP based handover signaling continues at 640 , where the 3GPP transceiver 602 commences SIP registration procedures.", "Signals 641 - 644 are used to exchange SIP addresses and to perform P-CSCF discovery for connecting the SIP layer in the 3GPP transceiver 602 to the IMS 606 via the 3GPP core network 604 .", "Signal 641 is exchanged between the 3GPP transceiver 602 upper layers and the non-3GPP transceiver 603 PHY layer using the crossover path 231 .", "Signal 642 is sent over the non-3GPP air interface from the non-3GPP transceiver 603 PHY layer to the non-3GPP CN 605 .", "Signal 643 is exchanged between the non-3GPP CN 605 and the 3GPP CN 604 and signal 644 is exchanged between the 3GPP CN 604 and the IMS 606 .", "Acknowledgment signals 645 and 646 are sent between the appropriate protocol layer in the Non-3GPP transceiver 603 and the 3GPP transceiver 602 upon successful SIP registration.", "With the SIP registration of the 3GPP transceiver 602 complete at 647 , SIP connectivity 648 and 649 is established between the 3GPP transceiver 602 and the 3GPP CN 604 , and between the 3GPP CN 604 and the IMS 606 , respectively.", "The 3GPP CN 604 informs the non-3GPP CN 605 that handover is complete with signal 650 .", "The non-3GPP transceiver 603 then performs SIP deregistration and IP release procedures 651 with the IMS 606 .", "The non-3GPP transceiver 603 receives signal 652 from the non-3GPP CN 605 indicating a handover complete, a radio switch OFF command and a release non-3GPP radio access bearer (RAB) command.", "The non-3GPP transceiver 603 informs the 3GPP transceiver 602 that the handover is complete with signal 653 , and the 3GPP radio transceiver 602 is activated ON.", "At 654 , the 3GPP transceiver 602 commences 3GPP RF connectivity procedures with the 3GPP CN 604 .", "FIGS. 7 and 8 show systematic block diagrams for the SIP based handover method described above.", "In FIG. 7 , communication links for a handover of WTRU 201 from a 3GPP source system to a non-3GPP target system is shown sequentially by signal paths 701 , 702 and 703 .", "Initially, the WTRU 201 is connected to the 3GPP source system on signal path 701 via an IMS 711 , a 3GPP CN 721 , and a 3GPP eNodeB (eNB) 722 that is in a wireless communication with the 3GPP PHY layer 223 .", "In order to prepare for handover to a non-3GPP target, a make-before-break path 702 is established to the non-3GPP transceiver protocol stack (i.e., SIP application layer 210 , SM and MM layer 211 , RRC and MAC layer 212 ) via the crossover path 241 between the 3GPP PHY layer 223 and non-3GPP RRC and MAC layer 212 .", "The communication path 702 allows the non-3GPP protocol stack to receive target system information via the active 3GPP source system using the 3GPP eNB 722 , the 3GPP CN 721 , which exchanges information with the target non-3GPP CN 731 , gateway (GW) 712 and IMS 711 .", "The communication path 702 is established when the WTRU 201 receives instructions from the source 3GPP system to start the access procedures toward the target system and to perform the sequence of access specific procedures (e.g., Attach, IP configuration, and SIP Registration).", "Upon successful completion of the access specific procedures and the SIP registration, the SIP connectivity is established as shown by communication path 703 between the non-3GPP protocol stack (i.e. layers 210 , 211 , 212 and PHY layer 213 ) and the non-3GPP radio access network (RAN) 732 , the non-3GPP CN 731 , the gateway (GW) 712 and IMS 711 .", "The WTRU 201 receives instructions from the 3GPP source system to switch (or handover) to the non-3GPP target system and turn off the radio on the 3GPP source system (i.e., turn OFF the 3GPP transceiver of WTRU 201 ), which terminates the communication links 701 and 702 .", "This ensures that the SIP based session is established to the non-3GPP target system.", "A WTRU controller 251 executes the access procedures and the handover procedures responsive to the received instructions from the 3GPP source system.", "In FIG. 8 , communication links for a handover of WTRU 201 from a non-3GPP source system to a 3GPP target system is shown sequentially by signal paths 801 , 802 and 803 .", "Initially, the WTRU 201 is connected to the non-3GPP source system on signal path 801 via an IMS 711 , a gateway (GW) 712 , a non-3GPP CN 731 , and a non-3GPP RAN 732 that is in a wireless communication with the non-3GPP PHY layer 213 .", "In order to prepare for handover to a 3GPP target system, a make-before-break path 802 is established between 3GPP target system to the 3GPP transceiver protocol stack (i.e., SIP application layer 220 , SM and MM layer 221 , RRC and MAC layer 222 ) via the crossover path 231 between the non-3GPP PHY layer 213 and non-3GPP RRC and MAC layer 222 .", "The communication path 802 allows the 3GPP protocol stack to receive target system information via the active non-3GPP source system using the non-3GPP RAN 732 , the non-3GPP CN 731 , which exchanges information with the target 3GPP CN 721 and IMS 711 .", "The communication path 802 is established when the WTRU 201 receives instructions from the source non-3GPP system to start the access procedures toward the 3GPP target system and to perform the sequence of access specific procedures (e.g., Attach, IP configuration, and SIP Registration).", "Upon successful completion of the access specific procedures and the SIP registration, the SIP connectivity is established as shown by communication path 803 between the 3GPP protocol stack (i.e. layers 220 , 221 , 222 and PHY layer 223 ) and the non-3GPP RAN 732 , followed by the non-3GPP CN 731 , the 3GPP CN 721 and IMS 711 .", "The WTRU 201 receives instructions from the 3GPP source system to switch (or handover) to the non-3GPP target system and turn off the radio on the 3GPP source system (i.e., turn OFF the non-3GPP transceiver of WTRU 201 ), which terminates the communication links 801 and 802 .", "This ensures that the SIP based session is established to the non-3GPP target system.", "A WTRU controller 251 executes the access procedures and the handover procedures responsive to the received instructions from the 3GPP source system.", "Although the features and elements of the present invention are described in the preferred embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the preferred embodiments or in various combinations with or without other features and elements of the present invention.", "The methods or flow charts provided in the present invention may be implemented in a computer program, software, or firmware tangibly embodied in a computer-readable storage medium for execution by a general purpose computer or a processor.", "Examples of computer-readable storage mediums include a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks, and digital versatile disks (DVDs).", "Suitable processors include, by way of example, a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits, any other type of integrated circuit (IC), and/or a state machine.", "A processor in association with software may be used to implement a radio frequency transceiver for use in a wireless transmit receive unit (WTRU), user equipment (UE), terminal, base station, radio network controller (RNC), or any host computer.", "The WTRU may be used in conjunction with modules, implemented in hardware and/or software, such as a camera, a video camera module, a videophone, a speakerphone, a vibration device, a speaker, a microphone, a television transceiver, a hands free headset, a keyboard, a Bluetooth® module, a frequency modulated (FM) radio unit, a liquid crystal display (LCD) display unit, an organic light-emitting diode (OLED) display unit, a digital music player, a media player, a video game player module, an Internet browser, and/or any wireless local area network (WLAN) module." ]
BACKGROUND OF THE INVENTION [0001] This invention relates to a laminated display window, especially for a handheld electronic device, which is resistant to delamination. [0002] It is desirable to provide a glass display window in a handheld electronic device such a media player or a mobile telephone. A glass window is more resistant to scratching than most plastic windows, and may be more suitable for certain types of touch-sensitive displays. [0003] One way to mount a display window is to provide a lip on the window, so that the window fits into the opening of a bezel, while the bezel captures the lip to retain the window. However, it is difficult to create a glass window with such a lip. Whether the glass is molded with a lip, or ground from a larger piece of glass, there may be stresses in such a piece of glass that make it more susceptible to breakage, either in handling before assembly into the device, or if the assembled device is dropped. [0004] One alternative is to laminate the window glass to a larger transparent substrate, which may be another piece of glass or a suitable plastic. The edges of the larger substrate protrude beyond the edges of the window glass to form the desired lip. However, this alternative is not without other difficulties, including, in particular, the risk of delamination. [0005] Lamination is frequently accomplished using a clear adhesive. However, many adhesives, while having high shear strength, have lower peel strength. Thus, any event, such as dropping of the device, that tends to try to separate the layers at the edges may cause delamination by peeling. This is particularly true if the laminated window structure is deformed at its corner, where the peel strength is lowest. Delamination is undesirable because it may compromise the strength of the laminated window or introduce defects into the visible area of the window, or, if there is a greater degree of delamination, it may create a safety hazard. [0006] It would be desirable to be able to provide a laminated display window with increased resistance to delamination. SUMMARY OF THE INVENTION [0007] In accordance with the present invention, delamination resistance of a laminated display window is increased by reducing the susceptibility of the laminated layers to peel along the edge, in the corners, or both. Thus, in addition to whatever method is used to bond the layers to one another, an adhesive may be placed in the corners or along part or all of the periphery of the outer window layer where the lip formed by the lower layer protrudes. This adhesive strengthens the bonding along those edges or in those corners, resisting delamination. [0008] Preferably, where the adhesive is used along the periphery, a channel or chamfer may be formed in which the adhesive is placed. This gives the adhesive more surface area to which to bond, and also decreases the risk of oozing of displaced adhesive. The channel or chamfer may be formed in one of the layers, and preferably in the lower, larger layer, or in the surrounding structure of the handheld device, such as in the display bezel. [0009] In addition, holes or gaps may be formed in the lip adjacent the edges and/or corners of the window glass to provide strain relief. If the lip were to be deformed by an event, it would not, at least in the areas of the holes or gaps, pull on the interface between the layers, thereby avoiding peeling apart the layers. The percentage of the periphery in which such holes or gaps are formed should not be so large that the lip is unable to reliably perform its function of retaining the window in the bezel. Preferably, such holes or gaps are formed only in the corners, and in any event are not formed along more than about 33% of the periphery. [0010] In another embodiment, the strain relief gaps or holes may be used alone, without the additional adhesive around the periphery. [0011] Therefore, in accordance with the present invention, there is provided a laminated window assembly for a device. The assembly includes (a) a window layer of a first substantially transparent material and having a periphery, and (b) a lip-forming layer, larger than the window layer, of a second substantially transparent material. The lip-forming layer extends beyond the window layer to form a lip for engaging the device. A substantially transparent bonding layer bonds the window layer to the lip-forming layer. An adhesive bead bonds the window layer to the lip-forming layer along at least one portion of the periphery. Holes may be formed in the lip for strain relief, to help prevent deformation of the lip from delaminating the assembly. If such strain relief is provided, it may be used with or without the adhesive bead. [0012] A device incorporating such a window assembly also is provided. BRIEF DESCRIPTION OF THE DRAWINGS [0013] Further features of the invention, its nature and various advantages, will be apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which: [0014] FIG. 1 is a perspective view of a laminated display window in accordance with the present invention; [0015] FIG. 2 is a cross-sectional view, taken from line 2 - 2 of FIG. 1 , of the laminated display window of FIG. 1 ; [0016] FIG. 3 is a fragmentary cross-sectional view of a device in which the laminated display window according to the present invention is mounted; [0017] FIG. 4 is a schematic view showing placement of adhesive at the corners of the laminated display window according to a preferred embodiment of the present invention; [0018] FIG. 5 is a schematic view showing placement of adhesive around the periphery of the laminated display window according to the present invention; [0019] FIG. 6 is a fragmentary cross-sectional view showing provision of a channel in one layer of a laminated display window in accordance with an embodiment of the present invention; [0020] FIG. 7 is a fragmentary cross-sectional view showing provision of a channel in one layer of a laminated display window in accordance with another embodiment of the present invention; [0021] FIG. 8 is a fragmentary perspective view showing provision of a channel in a bezel adjacent the laminated display window in accordance with an embodiment of the present invention; [0022] FIG. 9 is a fragmentary cross-sectional view showing provision of a channel in a bezel adjacent the laminated display window in accordance with an embodiment of the present invention; and [0023] FIG. 10 is a fragmentary perspective view showing provision of strain relief in accordance with an embodiment of the present invention. DETAILED DESCRIPTION [0024] A laminated display window assembly 10 with which the present invention may be used is shown in FIGS. 1 and 2 . Assembly 10 includes a window layer 11 , and a larger lip-forming layer 12 which is bonded to layer 11 by bonding layer 20 . For the reasons stated above, window layer 11 preferably is made of glass, although it may be made from a plastic material, and particularly from a high-molecular-weight plastic material that has many of the desirable characteristics of glass, such as scratch resistance. Other scratch-resistant clear materials, such as sapphire or quart crystal, also may be used. [0025] Lip-forming layer 12 preferably is made from a plastic material, which is more resistant to breakage than glass, but could also be made from glass. Lip-forming layer 12 preferably is sufficiently larger than window layer 11 to form a lip 120 large enough to securely retain assembly 10 in the device in which it is used. [0026] Although both window layer 11 and lip-forming layer 12 are preferably clear, either or both may include printing or decoration on either of its respective surfaces. [0027] Bonding layer 20 could be any suitable clear bond. For example, if both layers are plastic materials, the two layers could be heat-bonded to one another. However, where, as is preferred, at least one layer is glass, then preferably bonding layer 20 is a clear adhesive, and in particular a clear pressure-sensitive adhesive, or a clear liquid adhesive. [0028] Window layer 11 may be a flat glass sheet, preferably between about 0.50 mm and about 0.75 mm in thickness. Suitable glass sheets are available from Asahi Glass Co. Ltd., of Tokyo, Japan, and may be ground if necessary to a desired thickness, although other glass sheets may be used. In some embodiments, the final thickness of window layer 11 may be either 0.55 mm or 0.70 mm. In these embodiments, lip-forming layer 12 may be a 0.30 mm polycarbonate sheet available from Mitsubishi Engineering Plastics Corporation, of Tokyo, Japan (part number MR05GH), although another material could be used, and it may have another thickness. Finally, in this embodiment, bonding layer 20 may be a clear pressure-sensitive adhesive available from 3M Company, of St. Paul, Minn. (part number 8167 or 9483), although another clear pressure-sensitive or liquid adhesive could be used. These are only exemplary and any combination of materials, thicknesses and adhesives providing the desired properties—i.e., strength, clarity, etc.—may be used. [0029] It should be noted in this regard that while any material used for window layer 11 or lip-forming layer 12 should be as scratch-resistant as possible, the provision of a scratch-resistant coating or “hard coat” may decrease the adhesion between layers 11 and 12 . Therefore, it may be desirable to omit such coatings on the mating faces of layers 11 and 12 , with the understanding that the risk of scratching prior to assembly would be increased unless extra care to avoid scratching is taken. [0030] The fragmentary cross-sectional view of FIG. 3 shows how window assembly 10 is retained in an exemplary device 30 . A bezel 31 , affixed to casing 32 , has an extension 310 that extends over lip 120 to retain assembly 10 . Beneath assembly 10 there may be a display module 33 (e.g., a liquid crystal display), while space 34 may contain other components of the device (circuitry, batteries, etc.). A gasket 35 may be provided between bezel 31 and module 33 . [0031] Although window layer 11 is shown as a single clear sheet that fits within the opening of bezel 31 , it may be desirable to include one or more separate pieces that serve a decorative or functional purpose. For the purposes of this description and the claims that follow, any such collection of multiple pieces bonded to lip-forming layer 12 and fitting within the opening in bezel 31 may be considered collectively as window layer 11 . [0032] In accordance with the present invention, the risk of delamination of window assembly 10 —e.g., in case of a drop event—may be reduced by providing additional adhesive at the edge of window layer 11 adjacent lip-forming layer 12 . In one preferred embodiment 40 shown in FIG. 4 , adhesive 41 is applied at the corners of window layer 11 , providing additional adhesion where the peel strength is lowest. At the other extreme, in another preferred embodiment 50 shown in FIG. 5 , a bead 51 of additional adhesive extends completely around the periphery of window layer 11 adjacent layer 12 . In an intermediate embodiment (not shown), a plurality of shorter beads of adhesive may be provided along selective stretches of the edge of window layer 11 —less than the complete periphery as in FIG. 5 , but more than just the corners as in FIG. 4 . A suitable adhesive may be DP460 epoxy adhesive available from 3M Company and sold under the trademark SCOTCH-WELD®. [0033] In two variants 60 , 70 of embodiment 50 , a channel may be provided in lip-forming layer 12 in which adhesive bead 51 is placed. This gives the adhesive more surface area to which to bond, and also decreases the risk of oozing of displaced adhesive. In embodiment 60 ( FIG. 6 ), channel 61 has an arcuate cross section, while in embodiment 70 ( FIG. 7 ), channel 71 has a rectangular cross section. To avoid compromising the integrity of lip 120 , the depth of channel 61 / 71 preferably should not exceed about one-half of the thickness of lip 120 . [0034] Instead of providing a channel in lip-forming layer 12 , the channel may be provided in device 30 , and particularly in the portion adjacent window assembly 10 , which in the embodiments shown is bezel 31 . In the fragmentary perspective view of FIG. 8 , looking from the underside of window assembly 10 and bezel 31 , with part of window assembly 10 cut away, a rectangular channel 80 can be seen in bezel 31 for receiving adhesive bead 51 . Channel 80 also is shown in phantom in FIG. 9 , which primarily shows the provision, as an alternative to channel 80 , of a chamfer 90 to receive adhesive bead 51 . [0035] In addition to, or instead of, providing adhesive 41 / 51 , the risk of delamination of window assembly 10 can be reduced by providing strain relief features to reduce the peel forces resulting from deformation of lip 120 . FIG. 10 shows the provision of a hole or gap 100 in lip 120 adjacent corner 110 . of window layer 11 . The effect of providing hole or gap 100 is that in the case of flexing of lip 120 , as indicated by arrows 101 , no force is transmitted to adhesive interface 20 in the area of hole or gap 100 . [0036] Thus, in the case of flexing as shown in FIG. 10 , although there is transmission of peeling forces at locations 102 adjacent hole or gap 100 , there is no transmission of peeling force at corner 110 , where peel strength is lowest. It should be noted, however, the holes or gaps 100 could be provided in one or more locations elsewhere along the periphery of window layer 11 , instead of, or in addition to, corners 110 . One limitation is that the total amount of holes or gaps 100 should not be so great as to compromise the structural integrity of lip 120 . Generally, for that reason, holes or gaps 100 should occupy no more than about 33% of the periphery of window layer 11 . [0037] As noted above, strain relief holes or gaps 100 could be used instead of, or in addition to, adhesive 41 / 51 to reduce the risk of delamination of window assembly 10 . It will be appreciated, however, that if both adhesive 41 / 51 and strain relief holes or gaps 100 are used, then adhesive preferably should not be placed in holes or gaps 100 , lest force be transmitted across holes or gaps 100 by the adhesive, defeating the strain relief function. Thus, if holes or gaps 100 are placed in corners 110 as in FIG. 10 , then embodiment 40 of FIG. 4 , where adhesive 41 is present in corners 110 , should not be used. [0038] Thus it is seen that a laminated display window with increased delamination resistance has been provided. It will be understood that the foregoing is only illustrative of the principles of the invention, and that various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention, and the present invention is limited only by the claims that follow.
A laminated window assembly for a device, such as a handheld electronic device (e.g., a media player or mobile telephone), includes a window layer that preferably is glass, and a larger, substantially transparent lip-forming layer to which it is laminated, preferably by a substantially clear adhesive. Additional adhesive preferably is placed at at least portions of the edge of the window layer adjacent the lip-forming layer, especially at the corners, to resist delamination. Holes preferably are formed in the lip—e.g., at the corners—to resist the lip-forming layer peeling apart from the window layer forming layer. The holes preferably make up at most about 33% of the periphery of the window layer.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "BACKGROUND OF THE INVENTION [0001] This invention relates to a laminated display window, especially for a handheld electronic device, which is resistant to delamination.", "[0002] It is desirable to provide a glass display window in a handheld electronic device such a media player or a mobile telephone.", "A glass window is more resistant to scratching than most plastic windows, and may be more suitable for certain types of touch-sensitive displays.", "[0003] One way to mount a display window is to provide a lip on the window, so that the window fits into the opening of a bezel, while the bezel captures the lip to retain the window.", "However, it is difficult to create a glass window with such a lip.", "Whether the glass is molded with a lip, or ground from a larger piece of glass, there may be stresses in such a piece of glass that make it more susceptible to breakage, either in handling before assembly into the device, or if the assembled device is dropped.", "[0004] One alternative is to laminate the window glass to a larger transparent substrate, which may be another piece of glass or a suitable plastic.", "The edges of the larger substrate protrude beyond the edges of the window glass to form the desired lip.", "However, this alternative is not without other difficulties, including, in particular, the risk of delamination.", "[0005] Lamination is frequently accomplished using a clear adhesive.", "However, many adhesives, while having high shear strength, have lower peel strength.", "Thus, any event, such as dropping of the device, that tends to try to separate the layers at the edges may cause delamination by peeling.", "This is particularly true if the laminated window structure is deformed at its corner, where the peel strength is lowest.", "Delamination is undesirable because it may compromise the strength of the laminated window or introduce defects into the visible area of the window, or, if there is a greater degree of delamination, it may create a safety hazard.", "[0006] It would be desirable to be able to provide a laminated display window with increased resistance to delamination.", "SUMMARY OF THE INVENTION [0007] In accordance with the present invention, delamination resistance of a laminated display window is increased by reducing the susceptibility of the laminated layers to peel along the edge, in the corners, or both.", "Thus, in addition to whatever method is used to bond the layers to one another, an adhesive may be placed in the corners or along part or all of the periphery of the outer window layer where the lip formed by the lower layer protrudes.", "This adhesive strengthens the bonding along those edges or in those corners, resisting delamination.", "[0008] Preferably, where the adhesive is used along the periphery, a channel or chamfer may be formed in which the adhesive is placed.", "This gives the adhesive more surface area to which to bond, and also decreases the risk of oozing of displaced adhesive.", "The channel or chamfer may be formed in one of the layers, and preferably in the lower, larger layer, or in the surrounding structure of the handheld device, such as in the display bezel.", "[0009] In addition, holes or gaps may be formed in the lip adjacent the edges and/or corners of the window glass to provide strain relief.", "If the lip were to be deformed by an event, it would not, at least in the areas of the holes or gaps, pull on the interface between the layers, thereby avoiding peeling apart the layers.", "The percentage of the periphery in which such holes or gaps are formed should not be so large that the lip is unable to reliably perform its function of retaining the window in the bezel.", "Preferably, such holes or gaps are formed only in the corners, and in any event are not formed along more than about 33% of the periphery.", "[0010] In another embodiment, the strain relief gaps or holes may be used alone, without the additional adhesive around the periphery.", "[0011] Therefore, in accordance with the present invention, there is provided a laminated window assembly for a device.", "The assembly includes (a) a window layer of a first substantially transparent material and having a periphery, and (b) a lip-forming layer, larger than the window layer, of a second substantially transparent material.", "The lip-forming layer extends beyond the window layer to form a lip for engaging the device.", "A substantially transparent bonding layer bonds the window layer to the lip-forming layer.", "An adhesive bead bonds the window layer to the lip-forming layer along at least one portion of the periphery.", "Holes may be formed in the lip for strain relief, to help prevent deformation of the lip from delaminating the assembly.", "If such strain relief is provided, it may be used with or without the adhesive bead.", "[0012] A device incorporating such a window assembly also is provided.", "BRIEF DESCRIPTION OF THE DRAWINGS [0013] Further features of the invention, its nature and various advantages, will be apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which: [0014] FIG. 1 is a perspective view of a laminated display window in accordance with the present invention;", "[0015] FIG. 2 is a cross-sectional view, taken from line 2 - 2 of FIG. 1 , of the laminated display window of FIG. 1 ;", "[0016] FIG. 3 is a fragmentary cross-sectional view of a device in which the laminated display window according to the present invention is mounted;", "[0017] FIG. 4 is a schematic view showing placement of adhesive at the corners of the laminated display window according to a preferred embodiment of the present invention;", "[0018] FIG. 5 is a schematic view showing placement of adhesive around the periphery of the laminated display window according to the present invention;", "[0019] FIG. 6 is a fragmentary cross-sectional view showing provision of a channel in one layer of a laminated display window in accordance with an embodiment of the present invention;", "[0020] FIG. 7 is a fragmentary cross-sectional view showing provision of a channel in one layer of a laminated display window in accordance with another embodiment of the present invention;", "[0021] FIG. 8 is a fragmentary perspective view showing provision of a channel in a bezel adjacent the laminated display window in accordance with an embodiment of the present invention;", "[0022] FIG. 9 is a fragmentary cross-sectional view showing provision of a channel in a bezel adjacent the laminated display window in accordance with an embodiment of the present invention;", "and [0023] FIG. 10 is a fragmentary perspective view showing provision of strain relief in accordance with an embodiment of the present invention.", "DETAILED DESCRIPTION [0024] A laminated display window assembly 10 with which the present invention may be used is shown in FIGS. 1 and 2 .", "Assembly 10 includes a window layer 11 , and a larger lip-forming layer 12 which is bonded to layer 11 by bonding layer 20 .", "For the reasons stated above, window layer 11 preferably is made of glass, although it may be made from a plastic material, and particularly from a high-molecular-weight plastic material that has many of the desirable characteristics of glass, such as scratch resistance.", "Other scratch-resistant clear materials, such as sapphire or quart crystal, also may be used.", "[0025] Lip-forming layer 12 preferably is made from a plastic material, which is more resistant to breakage than glass, but could also be made from glass.", "Lip-forming layer 12 preferably is sufficiently larger than window layer 11 to form a lip 120 large enough to securely retain assembly 10 in the device in which it is used.", "[0026] Although both window layer 11 and lip-forming layer 12 are preferably clear, either or both may include printing or decoration on either of its respective surfaces.", "[0027] Bonding layer 20 could be any suitable clear bond.", "For example, if both layers are plastic materials, the two layers could be heat-bonded to one another.", "However, where, as is preferred, at least one layer is glass, then preferably bonding layer 20 is a clear adhesive, and in particular a clear pressure-sensitive adhesive, or a clear liquid adhesive.", "[0028] Window layer 11 may be a flat glass sheet, preferably between about 0.50 mm and about 0.75 mm in thickness.", "Suitable glass sheets are available from Asahi Glass Co", "Ltd., of Tokyo, Japan, and may be ground if necessary to a desired thickness, although other glass sheets may be used.", "In some embodiments, the final thickness of window layer 11 may be either 0.55 mm or 0.70 mm.", "In these embodiments, lip-forming layer 12 may be a 0.30 mm polycarbonate sheet available from Mitsubishi Engineering Plastics Corporation, of Tokyo, Japan (part number MR05GH), although another material could be used, and it may have another thickness.", "Finally, in this embodiment, bonding layer 20 may be a clear pressure-sensitive adhesive available from 3M Company, of St. Paul, Minn.", "(part number 8167 or 9483), although another clear pressure-sensitive or liquid adhesive could be used.", "These are only exemplary and any combination of materials, thicknesses and adhesives providing the desired properties—i.e., strength, clarity, etc.", "—may be used.", "[0029] It should be noted in this regard that while any material used for window layer 11 or lip-forming layer 12 should be as scratch-resistant as possible, the provision of a scratch-resistant coating or “hard coat”", "may decrease the adhesion between layers 11 and 12 .", "Therefore, it may be desirable to omit such coatings on the mating faces of layers 11 and 12 , with the understanding that the risk of scratching prior to assembly would be increased unless extra care to avoid scratching is taken.", "[0030] The fragmentary cross-sectional view of FIG. 3 shows how window assembly 10 is retained in an exemplary device 30 .", "A bezel 31 , affixed to casing 32 , has an extension 310 that extends over lip 120 to retain assembly 10 .", "Beneath assembly 10 there may be a display module 33 (e.g., a liquid crystal display), while space 34 may contain other components of the device (circuitry, batteries, etc.).", "A gasket 35 may be provided between bezel 31 and module 33 .", "[0031] Although window layer 11 is shown as a single clear sheet that fits within the opening of bezel 31 , it may be desirable to include one or more separate pieces that serve a decorative or functional purpose.", "For the purposes of this description and the claims that follow, any such collection of multiple pieces bonded to lip-forming layer 12 and fitting within the opening in bezel 31 may be considered collectively as window layer 11 .", "[0032] In accordance with the present invention, the risk of delamination of window assembly 10 —e.g., in case of a drop event—may be reduced by providing additional adhesive at the edge of window layer 11 adjacent lip-forming layer 12 .", "In one preferred embodiment 40 shown in FIG. 4 , adhesive 41 is applied at the corners of window layer 11 , providing additional adhesion where the peel strength is lowest.", "At the other extreme, in another preferred embodiment 50 shown in FIG. 5 , a bead 51 of additional adhesive extends completely around the periphery of window layer 11 adjacent layer 12 .", "In an intermediate embodiment (not shown), a plurality of shorter beads of adhesive may be provided along selective stretches of the edge of window layer 11 —less than the complete periphery as in FIG. 5 , but more than just the corners as in FIG. 4 .", "A suitable adhesive may be DP460 epoxy adhesive available from 3M Company and sold under the trademark SCOTCH-WELD®.", "[0033] In two variants 60 , 70 of embodiment 50 , a channel may be provided in lip-forming layer 12 in which adhesive bead 51 is placed.", "This gives the adhesive more surface area to which to bond, and also decreases the risk of oozing of displaced adhesive.", "In embodiment 60 ( FIG. 6 ), channel 61 has an arcuate cross section, while in embodiment 70 ( FIG. 7 ), channel 71 has a rectangular cross section.", "To avoid compromising the integrity of lip 120 , the depth of channel 61 / 71 preferably should not exceed about one-half of the thickness of lip 120 .", "[0034] Instead of providing a channel in lip-forming layer 12 , the channel may be provided in device 30 , and particularly in the portion adjacent window assembly 10 , which in the embodiments shown is bezel 31 .", "In the fragmentary perspective view of FIG. 8 , looking from the underside of window assembly 10 and bezel 31 , with part of window assembly 10 cut away, a rectangular channel 80 can be seen in bezel 31 for receiving adhesive bead 51 .", "Channel 80 also is shown in phantom in FIG. 9 , which primarily shows the provision, as an alternative to channel 80 , of a chamfer 90 to receive adhesive bead 51 .", "[0035] In addition to, or instead of, providing adhesive 41 / 51 , the risk of delamination of window assembly 10 can be reduced by providing strain relief features to reduce the peel forces resulting from deformation of lip 120 .", "FIG. 10 shows the provision of a hole or gap 100 in lip 120 adjacent corner 110 .", "of window layer 11 .", "The effect of providing hole or gap 100 is that in the case of flexing of lip 120 , as indicated by arrows 101 , no force is transmitted to adhesive interface 20 in the area of hole or gap 100 .", "[0036] Thus, in the case of flexing as shown in FIG. 10 , although there is transmission of peeling forces at locations 102 adjacent hole or gap 100 , there is no transmission of peeling force at corner 110 , where peel strength is lowest.", "It should be noted, however, the holes or gaps 100 could be provided in one or more locations elsewhere along the periphery of window layer 11 , instead of, or in addition to, corners 110 .", "One limitation is that the total amount of holes or gaps 100 should not be so great as to compromise the structural integrity of lip 120 .", "Generally, for that reason, holes or gaps 100 should occupy no more than about 33% of the periphery of window layer 11 .", "[0037] As noted above, strain relief holes or gaps 100 could be used instead of, or in addition to, adhesive 41 / 51 to reduce the risk of delamination of window assembly 10 .", "It will be appreciated, however, that if both adhesive 41 / 51 and strain relief holes or gaps 100 are used, then adhesive preferably should not be placed in holes or gaps 100 , lest force be transmitted across holes or gaps 100 by the adhesive, defeating the strain relief function.", "Thus, if holes or gaps 100 are placed in corners 110 as in FIG. 10 , then embodiment 40 of FIG. 4 , where adhesive 41 is present in corners 110 , should not be used.", "[0038] Thus it is seen that a laminated display window with increased delamination resistance has been provided.", "It will be understood that the foregoing is only illustrative of the principles of the invention, and that various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention, and the present invention is limited only by the claims that follow." ]
This is a continuation of application Ser. No. 07/413,685, filed Sep. 28, 1989, now abandoned. BACKGROUND OF THE INVENTION This invention relates to medium-caliber automatic firearms with a high rate of firing, particularly but not exclusively intended for equipping aircraft, and featuring a belt-fed cylinder supplied via a star-shaped feed mechanism. Such firearms, which can be single- or dual-barrelled, are gun gas actuated and electrically energized. Automatic firearms of the type involved must be capable of delivering short bursts with a high rate of firing reached from the very first rounds in order to engage extremely swift targets with a satisfactory hit probability. Very high burst firing rates are achieved using a single multi-barrel gun or several single- or dual-barrel guns installed on a common platform. Named after their inventor, single multi-barrel guns are typically of the "Gatling" type. They feature n barrels associated with as many bolts housed in a gun rotor. SUMMARY OF THE INVENTION This invention applies to and optimizes the multiple gun configuration mentioned above which uses guns that are more compact and lighter, thus easier to install, than the Gatling type guns, while also being safer since a misfired cartridge will remain in the chamber and firing will merely stop. As a counterpart, and considering the current technology which will be summarized hereunder, the rate of firing of the most recent guns of this type remains limited to approximately 1,800 rpm. The object of the invention is a medium-caliber firearm with a high rate of firing, that is, in excess of 1,800 rpm and possibly up to or even grater than 2,500 rpm, attained from the very start of each burst. Sufficiently compact and light for being easily housed on board an aircraft, this firearm also is to be as safe and reliable as any other firearm of the same type that is currently available. With this aim in view, the firearm of the type defined in the preamble is typical, as per the invention, in that it includes a star drum subject to indexed motion, which is in line with and rotated by the cylinder. The the star wheel, whose motion is synchronized with that of the star drum, is parallel to and to the side of said star drum. A stripper located between the star wheel and the star drum separates the cartridges from the links where the ammunition belt comes out of said star wheel so that said cartridges are subsequently routed individually to said star drum and that said links are evacuated from the firearm. Provisions are made for ramming the cartridges into the successive chambers of the cylinder after said cartridges are individually lined up with each of said chambers by the star drum as the latter rotates in indexed fashion. This arrangement allows the rate of firing to be increased regardless of the cartridge length. In conventional firearms, the ammunition belt transmits directly from the star wheel to the cylinder where a pusher expels the cartridges from the links, said star wheel being in line with said cylinder. The ammunition belt thus can be considered as "running through" the firearm, which implies a significant travel of the slide, strong inertia forces and a delay for the cylinder to reach its maximum revolution speed. All these factors result in a relatively low rate of firing. On the contrary, as per the invention, combining the star wheel, the stripper and the star drum allows said pusher to be eliminated and makes the axial travel of the slide, whose primary purpose is to rotate the cylinder and said star drum, independent of the cartridge length. The slide travel therefore can be minimized, and the duration of each firing cycle considerably reduced. For example, considering a conventional 250 mm-long cartridge, the slide travel as per the invention can be on the order of 80 mm only, whereas in conventional firearms travel of the pusher(s) exceeds 300 mm (breech type) or 130 mm (cylinder type). The stripper is preferably set up so as to expel the cartridges radially rather than axially, thus providing for a shorter overall length of the firearm. According to a preferable arrangement, the star drum-star wheel coupling can be disconnected so that the cylinder can be emptied by firing the cartridges that load the chambers of said cylinder at the time of disconnection. The star drum-star wheel coupling preferably includes a gear #1 pinioned on the star drum and meshing with a gear #2 attached to the star wheel at least during normal operation of the firearm. A clutch mechanism then can be installed between gear #2 and the star wheel shaft. This clutch favorably consists of teeth on gear #2 and teeth on a sleeve that rotates with and slides longitudinally on the star wheel shaft. The sleeve translation is controlled so that the star wheel and the star drum can be disconnected by separating said teeth. According to another favorable arrangement as per the invention, the star drum-star wheel coupling incorporates a damping device preferably consisting of a torsion bar. Since the star wheel shaft is hollow, said torsion bar is favorably located inside said shaft between the latter and gear #2. Finally, a drive mechanism with limited angular travel can be inserted between said hollow shaft and gear #2. This embodiment eliminates excessive stresses on ammunition belt links and consequently reduces firearm jamming hazards. Finally, the firearm whose cylinder features at least seven chambers also is typical in that the mechanism which successively loads the cartridges into said chambers of said cylinder includes the following: a fixed helical track which successively acts on the base end of each cartridge in order to combine their indexed rotation on the star drum with an indexed translation inside said star drum so that said cartridges are carried from the position where they are initially introduced in said star drum up to their individual firing position in the cylinder chambers; and a reciprocating slide which is actuated by explosive gases and controls the indexed rotation of the cylinder. The additional embodiment above allows the rate of firing to be further increased. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be discussed in detail hereafter using the appended drawings to support the description. FIGS. 1 and 2 illustrate a single-barrel firearm as per the invention and are respectively a longitudinal section taken on the axis of the single barrel and of the cylinder, and a cross section taken on line II--II shown in FIG. 1. FIGS. 3 and 4 are respectively axial and cross sectional views that sketch the positions of the cylinder, star drum and helical track, FIG. 4 showing an enlarged detail of FIG. 2. FIG. 5 is a mapping of axial sections showing the successive positions of a cartridge at each interruption of the indexed rotation of the cylinder the star drum. FIGS. 6 through 11 explain the operation of the slide that drives the cylinder, FIG. 7 being a fragmentary section taken on line VII--VII in FIG. 6 and FIG. 10 being a section taken on line X--X in FIG. 9. FIGS. 12 and 13 illustrate the ejection mechanism for empty cases, FIG. 12 being an enlarged view of a detail in FIG. 13. FIGS. 14 and 15 illustrate the firearm feed system and are respectively an axial section with phantom parts and a cross section at a larger scale. FIGS. 16 through 19 illustrate the actuating mechanism of the ammunition feed system and are respectively an axial section and cross sections taken on lines XVII--XVII, XVIII--XVIII and XIX.XIX in FIG. 16. FIGS. 20 through 22 are sketched views illustrating the operation of a dual-barrel firearm devised as a variant of the mode depicted in FIGS. 1 through 19. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The firearm illustrated in FIGS. 1 and 2 includes: a cylinder 1 rotating about its axis 2 and housing seven chambers 3 which all are mutually parallel and evenly distributed over a cylindrical spindle having the same axis 2 as cylinder 1; a slide 4 whose back and forth motion is parallel to axis 2 and which actuates cylinder 1 through a helical groove 5 hollowed out in said slide 4 and in which groove 5 permanently protrude two rollers 6 out of the seven rollers that are evenly distributed over the cylinder 1 circumference, the axis of both rollers 6 being in a same plane perpendicular to axis 2 of cylinder 1; a piston 7 capable of pushing slide 4 in the direction of arrow X (FIG. 1) under the pressure of the explosion gases collected at each firing cycle from a single barrel 8 through hole 9, the axis of said barrel 8 being parallel to axis 2 of cylinder 1; recoil springs 10 whose role will be specified later on; a star drum 11 aft of cylinder 1 and in line with axis 2 of said cylinder 1, said star drum 11 being revolved by said cylinder 1 via claws 42 (FIG. 14) and interacting with a feed star wheel 12 whose shaft 58 is parallel to but offset to the side of said axis 2 of said cylinder 1 so as to convey cartridges 57 to said cylinder 1; a stripper 13 which extracts from links 47 the cartridges 57 supplied in belts 45; a helical track 14 which is fixed in relation to the frame 15 of the firearm and whose role will be specified later on. The helical track 14 winds around star drum 11 over an angle of approximately 195°. Although it was assumed so far that there were seven chambers 3, seven rollers 6 and seven hollow positions on star drum 11, it should be noted that their number could as well be slightly greater than seven. The lower limit value of seven was selected as a satisfactory trade-off aimed at reducing the inertia forces affecting the cylinder 1 and star drum 11 assembly when both snap from one stop to the next, while keeping the lateral size of said assembly within reasonable limits. FIGS. 3 through 5 depict the successive positions of cartridges 57 as they result from the rotation of cylinder 1, in the direction of arrow R, during a firing sequence. Acquisition of a cartridge 57 takes place at station A. The base of case 59 of said cartridge 57 then rests on helical track 14 which progressively introduces (via stations B, C, D and E) said cartridge 57 in the facing chamber 3 of cylinder 1, up to station F where said cartridge 57 is fired, the empty case 59 being ejected from station G. The firearm operation can be broken down as follows: When cartridge 57 is fired at station F, part of the explosive gases rush through hole 9 and slam slide 4 which FIG. 1 shows in fore neutral position. During slide 4 travel, the two rollers 6 engaged in groove 5 make cylinder 1 rotate. Said groove 5 incorporates two switching devices 16 (FIGS. 6 and 7) pivoting about pins 17 and determining the path of said rollers 6 according to the forward or rearward motion of said slide 4. It should be noted that the simultaneous use of two rollers 6 for generating the rotation of cylinder 1 is only dictated by reliability considerations concerning the mechanical strength of the axle of said rollers 6, since the firearm can operate satisfactorily with only one roller engaged. The switching devices 16 are attached to pinions 18 (FIG. 7) secured by pins 19 and meshing with a rack 20. Said rack 20 is driven by and travels back and forth with respect to slide 4 perpendicularly to the firearm axis. The direction and amplitude of rack 20 motion are determined by guide rails 21 and 22 which are parallel to the firearm axis and are fixed on frame 15; the ends 23 and 24 of rack 20 (FIGS. 8 and 9) come to rest alternately on said guide rails 21 and 22. In order to maintain the switching devices 16 in a fixed and determined position during the motions of slide 4, rack 20 is locked on either one of guide rails 21 and 22 by protruding slugs 25 (FIGS. 10 and 11) which retract when pushed in by shoulders 26 cut in studs 27 that are secured on frame 15 and whose side faces act as stops combined with slugs 25 so as to intermittently freeze the translation of rack 20. When a cartridge 57 is fired, slide 4 is slammed by piston 7 in the direction X (FIGS. 1 and 6) and drags rollers 6 whose interaction with groove 5 and switching devices 16 up to the aft neutral position of said slide 4 causes cylinder 1 to move one-fourteenth of a revolution. Owing to the kinetic energy built up in cylinder 1 and to the action of the recoil springs 10, slide 4 is propelled forward. During this forward travel, rack 20 moves sideways and makes the switching devices 16 pivot. In a single to and fro cycle, the active roller 6 travels from position a to position b (FIG. 6) and cylinder 1 moves one-seventh of a revolution, which brings a new cartridge 57 to firing station F and empty case 59 to ejection station G. If firing stops at this instant, the recoil springs 10 maintain slide 4 in the fore neutral position and the firearm is ready to resume firing. When travelling back and forth, slide 4 drives a saddle 29 (FIGS. 12 and 13) that carries two tracks 30 and 31 which alternately press on the two legs 32 and 33 of an ejector 34 that pivots about an axle 35 secured on the firearm frame 15, so that the tip 36 of said ejector 34 can engage the groove 60 cut in the base end of case 59 (FIG. 12). During the firing sequence and when slide 4 initiates its rearward travel, track 31 starts pressing on leg 33 of ejector 34 and makes said ejector pivot so that tip 36 is brought in the plane of groove 60 in the base end of case 59. Ejector 34 is maintained in same position by leg 33 which rests on face 37 of saddle 29 until cylinder 1 rotates and brings the empty case 59 against tip 36, at which time track 30 of said saddle 29 hits leg 32 of said ejector 34 following the motion of slide 4 toward the fore neutral position. The empty case 59 then is ejected in a chute 38 and ejector 34 resumes its initial position (FIG. 13). When slide 4 is in the fore neutral position, cylinder 1 is prevented from rotating by mortises 39 which catch tenons 40 (FIG. 14) so that chambers 3 are correctly positioned opposite the electric primer 41 whose design is well known in the art. When rotating, cylinder 1 makes star drum 11 revolve by means of coupling claws 42 (FIG. 14). Said star drum 11 has seven branches which are the walls of an equivalent number of receptacles facing the seven chambers 3 of cylinder 1, and also has on its aft side a pinion 43 which meshes with a pinion 44 (FIG. 16) coupled with star wheel 12 by means of a device that will be detailed later on using FIGS. 16 through 19. The cartridges, in the form of an ammunition belt (FIG. 15) whose links 47 are pulled by star wheel 12, come opposite the stripper 13 which is secured on frame 15. Said stripper 13 is a fork with two parallel prongs 48 which are forced under the lids 49 in links 47 and thus expel cartridges 57 radially instead of axially as is usually done in most medium-caliber firearms available today. After being freed from its link 47, the cartridge is guided by a bearing surface 50 which pushes said cartridge into the facing receptacle in star drum 11. The base of the cartridge case then rests axially against helical track 14 whose action combined with the rotation of cylinder 1 progressively pushes said cartridge home in its chamber 3 in a sequence that begins at station A and ends at station E of said cylinder 1 (FIGS. 4 and 5). Separated from its cartridge 57, empty link 47 then is evacuated and consequently never penetrates inside the firearm. This arrangement eliminates the jamming hazard which prevails when the ammunition belt runs through the firearm since empty links often break loose and jam the feed mechanism or even cause such heavy damage that said firearm is no longer serviceable. High rates of firing generate sharp pulls that stress the ammunition belt by jerks. Links 47 therefore are likely to be bent out of shape, which makes the belt lengthen and may cause feed problems. This is why star wheel 12 is fitted with a damping device which smoothens out the tensile forces and makes belt lengthening negligible. Said damping device (FIGS. 16 through 19) mainly consists of a torsion bar 51 located between the shaft 58 of star wheel 12 and the pinion 44 that drives said star wheel. As shown in FIGS. 16 and 17, said shaft 58 is hollow and said torsion bar 51 is mounted inside said shaft 58. Star wheel 12 can be easily disengaged at any time, should the firearm be unloaded, for example. This is achieved through a claw coupling that consists of a sliding sleeve 52 whose external face supports a cylindrical rack 53 meshing with a pinion 54 which can be partially rotated on either side (as illustrated by double-end arrow in FIG. 16) by a lever that is not shown. On the side facing pinion 44, said sleeve 52 has teeth 55 that can mesh with teeth 56 of said pinion 44 (as illustrated in the upper part of FIG. 16) and that can be disengaged when pinion 54 rotates (as illustrated in the bottom part of FIG. 16). For torsion bar 51 to play its damper role, a limited relative angular travel (FIG. 18) is made possible between hollow shaft 58 of star wheel 12, on which is fixed one end of torsion bar 51, and pinion 44, in the hub 61 of which is fixed the other end of said torsion bar 51 (FIG. 16). Hollow shaft 58 and hub 61 have claws 62 and 63, respectively (FIG. 18), which mutually mesh through the limited angular travel mentioned above. In order to prevent the damages incurred by a cartridge 57 being introduced into an already loaded chamber 3, the firearm incorporates an electrical safety device which is not illustrated herein. This device can be: either a mechanical contact pressed by the base end of a case as long as said case is not ejected, or a proximity sensor detecting the presence of a case. In both cases, the contact/sensor delivers an electrical signal that is interpreted by the electronic logic circuits of the firearm which may decide to stop firing, if required. No mechanical shock occurs during the process and, consequently, there is no risk of damage to the firearm. In order to cope with a possible misfiring, the firearm incorporates a multiple-action rearming device that is known to the art and can be of pyrotechnic type. Although all of the above relates to a single-barrel 8 firearm, a dual-barrel variant can be envisaged along the same principle of operation. Such a configuration could be beneficial if the firearm were to be used on board a vehicle with a large ammunition storage capacity, in which case barrel wear and heating would be lessened. Using a single feed system and a single ejector together with two firing systems, and on condition that the explosive gases collection be adapted, a dual-barrel firearm could fire through each barrel alternately. For example, in a ten-chamber cylinder revolving in direction R and illustrated in FIGS. 20 through 22, stations A and C correspond to barrel #1 and barrel #2 respectively, station J is where the empty case is ejected and station I is where cartridge introduction begins; stations marked with a cross are those housing a cartridge not yet fired. The first firing cycle is initiated by firing the cartridge at station C (FIG. 20), which makes cylinder 1 rotate by one-tenth of a revolution. FIG. 21 illustrates the configuration reached upon completion of the first firing cycle. The second firing cycle is initiated by firing the cartridge at station A, which makes cylinder 1 rotate by an additional one-tenth of a revolution. FIG. 22 illustrates the configuration reached upon completion of the second firing cycle, said configuration being identical with the initial one. The third firing cycle then is initiated by firing the cartridge at station C. The above demonstrates that a dual-barrel firearm operates by firing through each barrel alternately. It only requires an adaptation of the firing system which also must feature an adequate safety device so as to prevent both barrels from firing simultaneously, in which case the firearm operation would stop and mechanical parts would likely break down due to the additional stresses generated by said simultaneous firing. On the other hand, and considering the greater inertia of the cylinder, the design rate of firing can be reduced. As compared with medium-caliber firearms known today, the firearm as per the invention is particularly performing and attractive owing to the numerous innovative features and characteristics that it embodies: lateral cartridge-link separation combined with the helical feed track 14, which allows the rate of firing to be increased regardless of cartridge length, as explained earlier in the firearm description. maximum rate of firing available instantaneously, which means that the single-barrel firearm can fire 21 rounds within a 0.5 s burst, superior reliability through redundancy (two active rollers, fully positive extractor control, auxiliary rearming system in case of misfiring etc.) and through feed system design, ergonomics (left-hand or right-hand side ammunition feed, star wheel disengagement capability) combined with compactness and light weight (approximately 110 kg), which all make the firearm particularly suitable for use on board an aircraft, overall design resulting, as per the invention, in a firearm that is simply and easy to operate.
A medium caliber automatic firearm with a high firing rate including a star drum which revolves in indexed fashion and which is in line with and driven by a cylinder star wheel, whose rotation is synchronized with that of the star drum, is mounted to the side of and is parallel to the star drum. A stripper is mounted between the star wheel and the star drum in order to separate cartridges from links at a point where the ammunition belt comes out of the star wheel while allowing the links to be evacuated from the firearm. A mechanism is also included which introduces the cartridges into successive chambers of the cylinder, the cartridges being lined up with the chambers by a star drum as the latter rotates.
Briefly outline the background technology and the problem the invention aims to solve.
[ "This is a continuation of application Ser.", "No. 07/413,685, filed Sep. 28, 1989, now abandoned.", "BACKGROUND OF THE INVENTION This invention relates to medium-caliber automatic firearms with a high rate of firing, particularly but not exclusively intended for equipping aircraft, and featuring a belt-fed cylinder supplied via a star-shaped feed mechanism.", "Such firearms, which can be single- or dual-barrelled, are gun gas actuated and electrically energized.", "Automatic firearms of the type involved must be capable of delivering short bursts with a high rate of firing reached from the very first rounds in order to engage extremely swift targets with a satisfactory hit probability.", "Very high burst firing rates are achieved using a single multi-barrel gun or several single- or dual-barrel guns installed on a common platform.", "Named after their inventor, single multi-barrel guns are typically of the "Gatling"", "type.", "They feature n barrels associated with as many bolts housed in a gun rotor.", "SUMMARY OF THE INVENTION This invention applies to and optimizes the multiple gun configuration mentioned above which uses guns that are more compact and lighter, thus easier to install, than the Gatling type guns, while also being safer since a misfired cartridge will remain in the chamber and firing will merely stop.", "As a counterpart, and considering the current technology which will be summarized hereunder, the rate of firing of the most recent guns of this type remains limited to approximately 1,800 rpm.", "The object of the invention is a medium-caliber firearm with a high rate of firing, that is, in excess of 1,800 rpm and possibly up to or even grater than 2,500 rpm, attained from the very start of each burst.", "Sufficiently compact and light for being easily housed on board an aircraft, this firearm also is to be as safe and reliable as any other firearm of the same type that is currently available.", "With this aim in view, the firearm of the type defined in the preamble is typical, as per the invention, in that it includes a star drum subject to indexed motion, which is in line with and rotated by the cylinder.", "The the star wheel, whose motion is synchronized with that of the star drum, is parallel to and to the side of said star drum.", "A stripper located between the star wheel and the star drum separates the cartridges from the links where the ammunition belt comes out of said star wheel so that said cartridges are subsequently routed individually to said star drum and that said links are evacuated from the firearm.", "Provisions are made for ramming the cartridges into the successive chambers of the cylinder after said cartridges are individually lined up with each of said chambers by the star drum as the latter rotates in indexed fashion.", "This arrangement allows the rate of firing to be increased regardless of the cartridge length.", "In conventional firearms, the ammunition belt transmits directly from the star wheel to the cylinder where a pusher expels the cartridges from the links, said star wheel being in line with said cylinder.", "The ammunition belt thus can be considered as "running through"", "the firearm, which implies a significant travel of the slide, strong inertia forces and a delay for the cylinder to reach its maximum revolution speed.", "All these factors result in a relatively low rate of firing.", "On the contrary, as per the invention, combining the star wheel, the stripper and the star drum allows said pusher to be eliminated and makes the axial travel of the slide, whose primary purpose is to rotate the cylinder and said star drum, independent of the cartridge length.", "The slide travel therefore can be minimized, and the duration of each firing cycle considerably reduced.", "For example, considering a conventional 250 mm-long cartridge, the slide travel as per the invention can be on the order of 80 mm only, whereas in conventional firearms travel of the pusher(s) exceeds 300 mm (breech type) or 130 mm (cylinder type).", "The stripper is preferably set up so as to expel the cartridges radially rather than axially, thus providing for a shorter overall length of the firearm.", "According to a preferable arrangement, the star drum-star wheel coupling can be disconnected so that the cylinder can be emptied by firing the cartridges that load the chambers of said cylinder at the time of disconnection.", "The star drum-star wheel coupling preferably includes a gear #1 pinioned on the star drum and meshing with a gear #2 attached to the star wheel at least during normal operation of the firearm.", "A clutch mechanism then can be installed between gear #2 and the star wheel shaft.", "This clutch favorably consists of teeth on gear #2 and teeth on a sleeve that rotates with and slides longitudinally on the star wheel shaft.", "The sleeve translation is controlled so that the star wheel and the star drum can be disconnected by separating said teeth.", "According to another favorable arrangement as per the invention, the star drum-star wheel coupling incorporates a damping device preferably consisting of a torsion bar.", "Since the star wheel shaft is hollow, said torsion bar is favorably located inside said shaft between the latter and gear #2.", "Finally, a drive mechanism with limited angular travel can be inserted between said hollow shaft and gear #2.", "This embodiment eliminates excessive stresses on ammunition belt links and consequently reduces firearm jamming hazards.", "Finally, the firearm whose cylinder features at least seven chambers also is typical in that the mechanism which successively loads the cartridges into said chambers of said cylinder includes the following: a fixed helical track which successively acts on the base end of each cartridge in order to combine their indexed rotation on the star drum with an indexed translation inside said star drum so that said cartridges are carried from the position where they are initially introduced in said star drum up to their individual firing position in the cylinder chambers;", "and a reciprocating slide which is actuated by explosive gases and controls the indexed rotation of the cylinder.", "The additional embodiment above allows the rate of firing to be further increased.", "BRIEF DESCRIPTION OF THE DRAWINGS The invention will be discussed in detail hereafter using the appended drawings to support the description.", "FIGS. 1 and 2 illustrate a single-barrel firearm as per the invention and are respectively a longitudinal section taken on the axis of the single barrel and of the cylinder, and a cross section taken on line II--II shown in FIG. 1. FIGS. 3 and 4 are respectively axial and cross sectional views that sketch the positions of the cylinder, star drum and helical track, FIG. 4 showing an enlarged detail of FIG. 2. FIG. 5 is a mapping of axial sections showing the successive positions of a cartridge at each interruption of the indexed rotation of the cylinder the star drum.", "FIGS. 6 through 11 explain the operation of the slide that drives the cylinder, FIG. 7 being a fragmentary section taken on line VII--VII in FIG. 6 and FIG. 10 being a section taken on line X--X in FIG. 9. FIGS. 12 and 13 illustrate the ejection mechanism for empty cases, FIG. 12 being an enlarged view of a detail in FIG. 13.", "FIGS. 14 and 15 illustrate the firearm feed system and are respectively an axial section with phantom parts and a cross section at a larger scale.", "FIGS. 16 through 19 illustrate the actuating mechanism of the ammunition feed system and are respectively an axial section and cross sections taken on lines XVII--XVII, XVIII--XVIII and XIX.", "XIX in FIG. 16.", "FIGS. 20 through 22 are sketched views illustrating the operation of a dual-barrel firearm devised as a variant of the mode depicted in FIGS. 1 through 19.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The firearm illustrated in FIGS. 1 and 2 includes: a cylinder 1 rotating about its axis 2 and housing seven chambers 3 which all are mutually parallel and evenly distributed over a cylindrical spindle having the same axis 2 as cylinder 1;", "a slide 4 whose back and forth motion is parallel to axis 2 and which actuates cylinder 1 through a helical groove 5 hollowed out in said slide 4 and in which groove 5 permanently protrude two rollers 6 out of the seven rollers that are evenly distributed over the cylinder 1 circumference, the axis of both rollers 6 being in a same plane perpendicular to axis 2 of cylinder 1;", "a piston 7 capable of pushing slide 4 in the direction of arrow X (FIG.", "1) under the pressure of the explosion gases collected at each firing cycle from a single barrel 8 through hole 9, the axis of said barrel 8 being parallel to axis 2 of cylinder 1;", "recoil springs 10 whose role will be specified later on;", "a star drum 11 aft of cylinder 1 and in line with axis 2 of said cylinder 1, said star drum 11 being revolved by said cylinder 1 via claws 42 (FIG.", "14) and interacting with a feed star wheel 12 whose shaft 58 is parallel to but offset to the side of said axis 2 of said cylinder 1 so as to convey cartridges 57 to said cylinder 1;", "a stripper 13 which extracts from links 47 the cartridges 57 supplied in belts 45;", "a helical track 14 which is fixed in relation to the frame 15 of the firearm and whose role will be specified later on.", "The helical track 14 winds around star drum 11 over an angle of approximately 195°.", "Although it was assumed so far that there were seven chambers 3, seven rollers 6 and seven hollow positions on star drum 11, it should be noted that their number could as well be slightly greater than seven.", "The lower limit value of seven was selected as a satisfactory trade-off aimed at reducing the inertia forces affecting the cylinder 1 and star drum 11 assembly when both snap from one stop to the next, while keeping the lateral size of said assembly within reasonable limits.", "FIGS. 3 through 5 depict the successive positions of cartridges 57 as they result from the rotation of cylinder 1, in the direction of arrow R, during a firing sequence.", "Acquisition of a cartridge 57 takes place at station A. The base of case 59 of said cartridge 57 then rests on helical track 14 which progressively introduces (via stations B, C, D and E) said cartridge 57 in the facing chamber 3 of cylinder 1, up to station F where said cartridge 57 is fired, the empty case 59 being ejected from station G. The firearm operation can be broken down as follows: When cartridge 57 is fired at station F, part of the explosive gases rush through hole 9 and slam slide 4 which FIG. 1 shows in fore neutral position.", "During slide 4 travel, the two rollers 6 engaged in groove 5 make cylinder 1 rotate.", "Said groove 5 incorporates two switching devices 16 (FIGS.", "6 and 7) pivoting about pins 17 and determining the path of said rollers 6 according to the forward or rearward motion of said slide 4.", "It should be noted that the simultaneous use of two rollers 6 for generating the rotation of cylinder 1 is only dictated by reliability considerations concerning the mechanical strength of the axle of said rollers 6, since the firearm can operate satisfactorily with only one roller engaged.", "The switching devices 16 are attached to pinions 18 (FIG.", "7) secured by pins 19 and meshing with a rack 20.", "Said rack 20 is driven by and travels back and forth with respect to slide 4 perpendicularly to the firearm axis.", "The direction and amplitude of rack 20 motion are determined by guide rails 21 and 22 which are parallel to the firearm axis and are fixed on frame 15;", "the ends 23 and 24 of rack 20 (FIGS.", "8 and 9) come to rest alternately on said guide rails 21 and 22.", "In order to maintain the switching devices 16 in a fixed and determined position during the motions of slide 4, rack 20 is locked on either one of guide rails 21 and 22 by protruding slugs 25 (FIGS.", "10 and 11) which retract when pushed in by shoulders 26 cut in studs 27 that are secured on frame 15 and whose side faces act as stops combined with slugs 25 so as to intermittently freeze the translation of rack 20.", "When a cartridge 57 is fired, slide 4 is slammed by piston 7 in the direction X (FIGS.", "1 and 6) and drags rollers 6 whose interaction with groove 5 and switching devices 16 up to the aft neutral position of said slide 4 causes cylinder 1 to move one-fourteenth of a revolution.", "Owing to the kinetic energy built up in cylinder 1 and to the action of the recoil springs 10, slide 4 is propelled forward.", "During this forward travel, rack 20 moves sideways and makes the switching devices 16 pivot.", "In a single to and fro cycle, the active roller 6 travels from position a to position b (FIG.", "6) and cylinder 1 moves one-seventh of a revolution, which brings a new cartridge 57 to firing station F and empty case 59 to ejection station G. If firing stops at this instant, the recoil springs 10 maintain slide 4 in the fore neutral position and the firearm is ready to resume firing.", "When travelling back and forth, slide 4 drives a saddle 29 (FIGS.", "12 and 13) that carries two tracks 30 and 31 which alternately press on the two legs 32 and 33 of an ejector 34 that pivots about an axle 35 secured on the firearm frame 15, so that the tip 36 of said ejector 34 can engage the groove 60 cut in the base end of case 59 (FIG.", "12).", "During the firing sequence and when slide 4 initiates its rearward travel, track 31 starts pressing on leg 33 of ejector 34 and makes said ejector pivot so that tip 36 is brought in the plane of groove 60 in the base end of case 59.", "Ejector 34 is maintained in same position by leg 33 which rests on face 37 of saddle 29 until cylinder 1 rotates and brings the empty case 59 against tip 36, at which time track 30 of said saddle 29 hits leg 32 of said ejector 34 following the motion of slide 4 toward the fore neutral position.", "The empty case 59 then is ejected in a chute 38 and ejector 34 resumes its initial position (FIG.", "13).", "When slide 4 is in the fore neutral position, cylinder 1 is prevented from rotating by mortises 39 which catch tenons 40 (FIG.", "14) so that chambers 3 are correctly positioned opposite the electric primer 41 whose design is well known in the art.", "When rotating, cylinder 1 makes star drum 11 revolve by means of coupling claws 42 (FIG.", "14).", "Said star drum 11 has seven branches which are the walls of an equivalent number of receptacles facing the seven chambers 3 of cylinder 1, and also has on its aft side a pinion 43 which meshes with a pinion 44 (FIG.", "16) coupled with star wheel 12 by means of a device that will be detailed later on using FIGS. 16 through 19.", "The cartridges, in the form of an ammunition belt (FIG.", "15) whose links 47 are pulled by star wheel 12, come opposite the stripper 13 which is secured on frame 15.", "Said stripper 13 is a fork with two parallel prongs 48 which are forced under the lids 49 in links 47 and thus expel cartridges 57 radially instead of axially as is usually done in most medium-caliber firearms available today.", "After being freed from its link 47, the cartridge is guided by a bearing surface 50 which pushes said cartridge into the facing receptacle in star drum 11.", "The base of the cartridge case then rests axially against helical track 14 whose action combined with the rotation of cylinder 1 progressively pushes said cartridge home in its chamber 3 in a sequence that begins at station A and ends at station E of said cylinder 1 (FIGS.", "4 and 5).", "Separated from its cartridge 57, empty link 47 then is evacuated and consequently never penetrates inside the firearm.", "This arrangement eliminates the jamming hazard which prevails when the ammunition belt runs through the firearm since empty links often break loose and jam the feed mechanism or even cause such heavy damage that said firearm is no longer serviceable.", "High rates of firing generate sharp pulls that stress the ammunition belt by jerks.", "Links 47 therefore are likely to be bent out of shape, which makes the belt lengthen and may cause feed problems.", "This is why star wheel 12 is fitted with a damping device which smoothens out the tensile forces and makes belt lengthening negligible.", "Said damping device (FIGS.", "16 through 19) mainly consists of a torsion bar 51 located between the shaft 58 of star wheel 12 and the pinion 44 that drives said star wheel.", "As shown in FIGS. 16 and 17, said shaft 58 is hollow and said torsion bar 51 is mounted inside said shaft 58.", "Star wheel 12 can be easily disengaged at any time, should the firearm be unloaded, for example.", "This is achieved through a claw coupling that consists of a sliding sleeve 52 whose external face supports a cylindrical rack 53 meshing with a pinion 54 which can be partially rotated on either side (as illustrated by double-end arrow in FIG. 16) by a lever that is not shown.", "On the side facing pinion 44, said sleeve 52 has teeth 55 that can mesh with teeth 56 of said pinion 44 (as illustrated in the upper part of FIG. 16) and that can be disengaged when pinion 54 rotates (as illustrated in the bottom part of FIG. 16).", "For torsion bar 51 to play its damper role, a limited relative angular travel (FIG.", "18) is made possible between hollow shaft 58 of star wheel 12, on which is fixed one end of torsion bar 51, and pinion 44, in the hub 61 of which is fixed the other end of said torsion bar 51 (FIG.", "16).", "Hollow shaft 58 and hub 61 have claws 62 and 63, respectively (FIG.", "18), which mutually mesh through the limited angular travel mentioned above.", "In order to prevent the damages incurred by a cartridge 57 being introduced into an already loaded chamber 3, the firearm incorporates an electrical safety device which is not illustrated herein.", "This device can be: either a mechanical contact pressed by the base end of a case as long as said case is not ejected, or a proximity sensor detecting the presence of a case.", "In both cases, the contact/sensor delivers an electrical signal that is interpreted by the electronic logic circuits of the firearm which may decide to stop firing, if required.", "No mechanical shock occurs during the process and, consequently, there is no risk of damage to the firearm.", "In order to cope with a possible misfiring, the firearm incorporates a multiple-action rearming device that is known to the art and can be of pyrotechnic type.", "Although all of the above relates to a single-barrel 8 firearm, a dual-barrel variant can be envisaged along the same principle of operation.", "Such a configuration could be beneficial if the firearm were to be used on board a vehicle with a large ammunition storage capacity, in which case barrel wear and heating would be lessened.", "Using a single feed system and a single ejector together with two firing systems, and on condition that the explosive gases collection be adapted, a dual-barrel firearm could fire through each barrel alternately.", "For example, in a ten-chamber cylinder revolving in direction R and illustrated in FIGS. 20 through 22, stations A and C correspond to barrel #1 and barrel #2 respectively, station J is where the empty case is ejected and station I is where cartridge introduction begins;", "stations marked with a cross are those housing a cartridge not yet fired.", "The first firing cycle is initiated by firing the cartridge at station C (FIG.", "20), which makes cylinder 1 rotate by one-tenth of a revolution.", "FIG. 21 illustrates the configuration reached upon completion of the first firing cycle.", "The second firing cycle is initiated by firing the cartridge at station A, which makes cylinder 1 rotate by an additional one-tenth of a revolution.", "FIG. 22 illustrates the configuration reached upon completion of the second firing cycle, said configuration being identical with the initial one.", "The third firing cycle then is initiated by firing the cartridge at station C. The above demonstrates that a dual-barrel firearm operates by firing through each barrel alternately.", "It only requires an adaptation of the firing system which also must feature an adequate safety device so as to prevent both barrels from firing simultaneously, in which case the firearm operation would stop and mechanical parts would likely break down due to the additional stresses generated by said simultaneous firing.", "On the other hand, and considering the greater inertia of the cylinder, the design rate of firing can be reduced.", "As compared with medium-caliber firearms known today, the firearm as per the invention is particularly performing and attractive owing to the numerous innovative features and characteristics that it embodies: lateral cartridge-link separation combined with the helical feed track 14, which allows the rate of firing to be increased regardless of cartridge length, as explained earlier in the firearm description.", "maximum rate of firing available instantaneously, which means that the single-barrel firearm can fire 21 rounds within a 0.5 s burst, superior reliability through redundancy (two active rollers, fully positive extractor control, auxiliary rearming system in case of misfiring etc.) and through feed system design, ergonomics (left-hand or right-hand side ammunition feed, star wheel disengagement capability) combined with compactness and light weight (approximately 110 kg), which all make the firearm particularly suitable for use on board an aircraft, overall design resulting, as per the invention, in a firearm that is simply and easy to operate." ]
FIELD OF THE INVENTION [0001] The present invention relates generally to animal cage guards. More specifically, the invention relates to a simple, easy to use cage guard which conforms to the bottom and lower side portions of a cage to keep refuse in the cage while permitting relatively unobstructed viewing of the upper portions of the cage. BACKGROUND OF THE INVENTION [0002] Pet cages are typically a wire or barred cage with a floor. The wires or bars making up the sides of the cage are generally uncovered, because an unobstructed view of the animal is preferred. Although this type of design is advantageous for viewing the pet, it often leads to spillage of debris, food, and even unsanitary animal waste, as these substances are likely to pass through the bars or wires making up the sides of the cage. This creates a continuing duty on the part of the pet owner to clean the floors or walls of the area of the home where the cage is placed. [0003] One proposed prior art solution to this problem in the context of bird cages appears in U.S. Pat. No. 1,094,423 to Brandt, which generally teaches a fabric netting structure which attaches to a bird cage by a hook or the like, and which hangs loosely under the cage. Litter expelled from the cage is meant to be caught by the fabric underhanging the cage. This type of cage attachment has the disadvantage of being difficult to remove, difficult to clean, and is prone to accidental spillage. The accidental spillage can occur during cleaning, or debris might escape from the sides of the cage, missing the hanging attachment. [0004] Another proposed solution has been a rectangular attachment which wraps around or envelops the sides of a cage, and is held in place by Velcro or elastic. This design fails to fully solve the problem of debris being ejected from the cage and into the home environment, however, as there is a gap between the bottom and side of the cage allowing for leakage of debris, particularly liquids. [0005] Accordingly, there exists a need for an improved cage guard which minimizes or prevents unwanted matter from being dispelled from a pet cage. SUMMARY OF THE INVENTION [0006] The present invention solves the problems noted above by providing a cage guard which is durable, easy to use, and which conforms to both the lower sides and bottom of a pet cage. [0007] In one embodiment, the cage guard of the present invention comprises a flexible relatively nonporous bottom designed to conform and snugly fit the bottom of a pet cage. The bottom is attached or integrally formed with a flexible relatively nonporous lower side, which is adapted to conform and snugly fit to the lower sides of a pet cage. The relatively nonporous lower side is in turn attached or integrally formed with a relatively porous upper side which covers a portion of the sides of the cage above those covered by the relatively nonporous lower side. [0008] This design has the advantage of keeping debris from being ejected from lower portions of the cage or slipping through gaps to spill into the home environment. The nonporous lower side advantageously keeps very small particles, fluids and excretions within the cage. The relatively porous upper side permits easy viewing while keeping larger flying particles within the cage. The cage guard is secured to the cage by an elastomeric band attached to the porous upper side. The elastomeric band may extend along the entirety of the circumference of the porous upper side, or along less than the entirety provided that elastomeric band provides sufficient force radially inward to hold the cage guard in place. [0009] In another embodiment of the present invention, there is provided an animal cage guard which is composed of a flexible nonporous bottom attached directly to porous sides. The porous sides are provided with an elastomeric band along an at least an upper portion of the circumference of the porous sides to secure the cage guard to an animal cage. The bottom and porous sides are dimensioned such that they are capable of conforming to the shape of the lower portion of the cage. Consequently, this embodiment eliminates the nonporous lower side discussed above. [0010] Preferably, the materials used to manufacture the cage guard are machine washable. Moreover, in some embodiments, it may be desirable to waterproof the nonporous portions, particularly when used with animals likely to expel fluids from lower portions of the cage. [0011] The bottom is preferably constructed of a medium to heavy-weight fabric or fabric-like material, such as polycotton, burlap, polyester, polyester blends, trigger poplin, nylon, vinyl, and Gore-tex™. The nonporous lower side is preferably constructed of the same material as the bottom. The porous side is preferably constructed of a weaved material. For example, the porous side may be constructed of mesh netting, nylon tulle, or an elastic mesh. It is preferred that the porous side have a mesh gauge having apertures smaller than the largest particle which might be ejected from the cage. Depending upon the type of animal kept, the present inventor has found gauge of about 0.1 mm through 3 mm adequate, with 0.2-1 mm being preferred for birds. [0012] The elastomeric band used to secure the cage guard to the cage may take the form of an elastic band, a rubber band, or similar elastomeric structure known to those of skill in the art. Alternately, the elastomeric band may be eliminated where the porous upper sides are formed of elastomeric materials. [0013] In its preferred embodiment, the cage guard of the present invention is used with a bird cage. This is because birds tend to reside in the upper portions of their cages, and consequently, the nonporous side will not interfere with most of the viewing of the birds. BRIEF DESCRIPTION OF THE DRAWINGS [0014] [0014]FIG. 1 is a perspective view showing an animal cage employing the animal cage guard of the present invention on a cage having a square cross-sectional shape. [0015] [0015]FIG. 2 is a side view showing the animal cage guard of FIG. 1. [0016] [0016]FIG. 3 is a top view of the animal cage guard of FIG. 1. [0017] [0017]FIG. 4 is a bottom view of the animal cage guard of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0018] The animal cage guard of the present invention is a simple to use barrier which can be fitted to a variety of pet cages for the purpose of catching and holding debris or spillage from lower portions of the cage where such spillage is most likely. Furthermore, the cage guard of the present invention is easy to remove and clean. It conforms to the cage sides and bottom and therefore minimizes or eliminates gaps through which debris might otherwise slip through. This allows the owner to enjoy the pet without the mess and unsanitary conditions that might otherwise occur. In addition, the invention is simple and durable, and can be manufactured and sold at a reasonable cost. Although described in connection with square cage designs, it should be understood that the invention is not so limited, as it is easily adaptable to other shapes as well as sizes of cages. For example, the cage guard of the present invention may be used with cages having oval, triangular, pentagonal, hexagonal, or other geometrical cross-sectional configurations. The manner of adapting the present invention to the other embodiments will become apparent to those of skill in the art in view of the teachings herein. [0019] Furthermore, the cage guard of the present invention can be used for any animal cage which might have the problem of spillage from the lower sides. It is particularly advantageous for a bird cage, and particularly a hanging bird cage or a bird cage which rests on a surface. However, the cage guard can be used for a rodent, reptile, rabbit, or any other type of animal cage. [0020] An embodiment of cage guard 5 of the present invention is illustrated in FIGS. 1 - 4 . Referring to FIG. 1, cage guard 5 is shown fitted over cage 50 . Cage 50 may be any conventional wire or barred cage as known to those of skill in the art. As shown in FIG. 1, cage 50 has a square cross-sectional shape, and thus a square bottom. The sides and bottom of cage guard 5 conform to the lower outer dimensions of cage 50 , and particularly the bottom and lower sides of cage 50 , and thus have a square or cross-sectional shape, as shown in FIGS. 1 - 4 . By conform, it is meant that the inner surfaces of cage guard 5 substantially fit to and contact the outer bottom and lower side surfaces of cage 50 . In use, cage guard 5 is slipped over the bottom and sides of the cage 50 , and is held in place by means of elastomeric band 40 , as shown in FIG. 1. [0021] Cage guard 5 generally comprises a bottom 10 , a lower side 20 , a porous upper side 30 , and an elastomeric band 40 to secure cage guard 5 to the cage. As shown in FIG. 1, cage guard 5 functions to keep food and debris in the cage and to keep liquid and secretions inside the cage, because the lower side 20 is relatively nonporous, and prevents liquids and very small particles from being expelled, while the porous upper side 30 functions to deflect larger size refuse back into the lower portion of the cage, or into a “waste receptacle” defined by the sides and bottom portion 10 . Advantageously, the home or room in which the pet is kept will be free of debris and waste which would otherwise be expelled from the cage. [0022] Referring to FIGS. 1 - 4 , flexible bottom 10 is a particularly advantageous part of the present invention because it conforms to the cage and keeps debris from falling to the floor. The term flexible is used to mean that the material chosen for the bottom 10 is capable of conforming to the bottom of the selected cage. Bottom 10 is also preferably nonporous. The term nonporous is used to mean that the material used for bottom 10 does not have large openings or pores through which animal debris may pass. Bottom 10 may be constructed of materials which permit diffusion of gases through bottom 10 , such as air. Bottom 10 may also be constructed of materials that will pass liquids, although in most embodiments of the present invention, it is preferred that bottom 10 prevent or minimize liquid flow therethrough and thus be waterproofed. [0023] In a preferred embodiment, bottom 10 is selected in view of the type of refuse which a particular animal might expel from the bottom side portions of a cage. For example, birds tend to eject droppings and water from the bottom portions of their cages, and portion 10 is selected to prevent such refuse from being expelled. Particularly suitable materials for construction of bottom 10 include medium to heavy fabrics, either natural or synthetic. Such a fabric may include polycotton, burlap, polyester, polyester blends, trigger poplin, nylon, vinyl, denim, spandex, and waterproof materials such as GORETEX™, as well as other similar materials known to those of skill in the art. [0024] In some embodiments, it may be desirable to construct bottom 10 of waterproof materials. This embodiment is particularly advantageous where it is expected that water or other fluids may be expelled from the cage. When bottom 10 is constructed of waterproof materials and cage guard 5 is fitted over the cage, expelled liquids will be trapped within the region defined by the interior of bottom 10 and lower side 20 , which function as a waterproof waste receptacle. Bottom 10 may be waterproofed in a variety of ways. For example, bottom 10 may be treated chemically to waterproof it, or it may be constructed of waterproof materials. This may include the addition of a second layer of waterproof material lining bottom 10 and lower side 20 . Waterproof materials may include flexible plastics and other synthetics, as known to those of skill in the art. [0025] In the embodiment shown in FIGS. 1 - 4 , bottom 10 is attached to or integrally formed with lower side 20 . In a preferred embodiment, side portion 20 is relatively nonporous, and is preferably constructed of materials similar to those used for bottom 10 . Side 20 may also be constructed of translucent materials, such as plastics, to permit easier viewing of the lower portions of the cage. In some embodiments, it may also be desirable to construct bottom 10 out of different materials than lower side 20 . [0026] Bottom 10 is preferably be attached to nonporous lower side 20 in such a way that there is no gap therebetween. Such attachment may comprise sewing, fusing, or adhesively bonding the portions together, or other attachment means known to those of skill in the art. [0027] As is shown in FIGS. 1 - 4 , porous upper side 30 is attached to lower side 20 . Such attachment can be by any means known to those of skill in the art, and particularly those noted above. Porous side 30 of the present invention offers the ability to view the animal without obstruction which might be created by the nonporous sides if the nonporous sides are constructed of opaque materials. Porous side 30 also permits air to freely flow therethrough, for the enjoyment and health of the animal. Porous side 32 may have a variety of gauges. Gauge refers to the spaces or pores between the fibers of the mesh. The mesh is preferably a small enough gauge that excretions will be contained within the cage or it can be of a large mesh to allow for better viewing. Porous side 30 can be chosen in a variety of tightness of weave or gap such that it will keep different sized flying debris, or even excretions in the cage without obstructing the view. In one embodiment, porous side 30 is made up of a large weave fabric or net, having openings of from about 2 mm-3 mm. This size of opening would be sufficient to keep most cage debris from being ejected from the cage, such as a bird cage, but will not prevent liquids from being expelled. Porous side 30 is preferably made up of a material such as nylon mesh net or nylon tulle which is stiff yet flexible enough to fit to the sides of the cage. In some embodiments, porous side 30 may be constructed of elastomeric materials which secure cage guard 5 to the cage without need for band 40 . [0028] In one preferred embodiment the gauge of the porous side 30 is smaller than the smallest solid particle that may likely exit the cage at the particular point where the gauge is positioned. Thus, for example, if an animal tends to expel larger size refuse from upper portions of the cage and smaller size refuse from lower portions, the gauge of the lower portions may be selected to be smaller than that of the upper portions. Advantageously, the larger gauge of the upper portions facilitates viewing of the animal. Preferably, the porous side 30 is made of a material which is machine washable to allow for easy clean-up. [0029] Porous side portion 30 may have an elastomeric band 40 along a portion of the circumference of the porous side 30 or along the entire circumference. Band 40 secures cage guard 5 to cage 50 . Furthermore, band 40 is preferably selected to allow for easy removal and mounting of the cage guard, and to permit the side portions 20 and 30 to conform closely to the cage without gaps. [0030] Band 40 may be made of any substance that allows for the above conditions. One class of materials found suitable are elastomeric materials. These may include an elastic band, a rubber band, or spandex. Alternatively, separate band 40 may be eliminated if porous side 30 are made of a stretchable material which can, in and of itself, conform to the cage and hold the cage guard in place. [0031] In an alternate embodiment, lower side 20 is eliminated, and bottom 10 is attached directly to porous upper side 30 , such that the lower sides of the cage are encompassed within conforming porous upper side 30 . In this embodiment, porous side 30 may have lower regions of small gauge, as for example 2-3 inches along the bottom of a cage, and open regions with larger gauge. This embodiment is advantageous for pet cages housing pets which spend most of their time in lower portions of the cage, such as rodents, because the porous side 30 permits easier viewing of the pet. [0032] One unique advantage of the cage guard of the present invention is its ability to conform to the lower portions of the pet cage. As described above, this is accomplished by choosing materials which are flexible enough to be pulled over the cage, and by dimensioning the cage guard so that its cross-sectional shape and area are within a range sufficient to permit the cage guard to conform. For example, if a cage has a square cross-sectional shape with sides of 12 inches, bottom 10 preferably has a square cross-sectional shape, and sides of slightly larger than 12 inches. The height of sides 20 and 30 can be varied as needed to accommodate the animal kept. For birds, it is preferred that side 20 have a height of 2-5 inches, and side 30 a height of 5-10 inches, although these are not limiting values and can be varied as desired to optimize viewing enjoyment and still prevent waste expulsion. Where elastomeric band 40 is used, it is preferred that it have an unstretched circumference slightly smaller than the circumference of the cage, and stretched circumference larger than the circumference of the cage, so that a radial inward force is generated when the cage guard 5 is fixed on a cage, to hold the cage guard in place. [0033] Alternatively, the cage guard of the present invention may be of a different cross-sectional shape or larger area, but still conform to the cage by means of fasteners which can be adjusted to conform the cage guard to the cage. In one embodiment these additional fasteners can be velcro fasteners, positioned at points along the sides of the cage guard to eliminate slack. For example, Velcro hooks can be provided near the edges of the lower sides on upper sides, with the mating Velcro piece attached to the adjacent side near the edge, such that the two mating Velcro pieces can be secured to remove slack from the cage guard. Hooks, buttons, snap fasteners and the like might also be used in place of Velcro. These fasteners can be incorporated into various points of sides 20 and 30 to allow for tightening the sides 20 and 30 to the cage at the corners or elsewhere. [0034] The cage guard of the present invention can be constructed in such a way that it is inexpensive to produce yet durable. It can also be constructed in such a way that it is machine washable and thus easy to clean and keep sanitary. Lastly, it can be constructed in such a way that it will keep debris and excretions from exiting the cage and depositing on walls, floors, and furniture thus allowing the user to enjoy the animal without undue or unsanitary discomfort. [0035] From the foregoing description, additional advantages and novel features or alternatives will be apparent to one of skill in the art. [0036] It should be understood that changes may be made in the construction and in the combination and arrangement of the several parts, provided that such changes fall within the scope of the appended claims.
A cage guard which is adaptable to a variety of cage shapes and types is described in the present invention. The cage guard is a flexible form composed of a nonporous bottom portion, an optional nonporous side portion, a porous side portion, and means to secure the cage guard to a cage. The cage guard is produced in such a way that it conforms to the cage. This gives the cage guard the advantageous property of keeping debris and excretions inside the cage so the animal can be enjoyed in a clean, sanitary way.
Identify and summarize the most critical features from the given passage.
[ "FIELD OF THE INVENTION [0001] The present invention relates generally to animal cage guards.", "More specifically, the invention relates to a simple, easy to use cage guard which conforms to the bottom and lower side portions of a cage to keep refuse in the cage while permitting relatively unobstructed viewing of the upper portions of the cage.", "BACKGROUND OF THE INVENTION [0002] Pet cages are typically a wire or barred cage with a floor.", "The wires or bars making up the sides of the cage are generally uncovered, because an unobstructed view of the animal is preferred.", "Although this type of design is advantageous for viewing the pet, it often leads to spillage of debris, food, and even unsanitary animal waste, as these substances are likely to pass through the bars or wires making up the sides of the cage.", "This creates a continuing duty on the part of the pet owner to clean the floors or walls of the area of the home where the cage is placed.", "[0003] One proposed prior art solution to this problem in the context of bird cages appears in U.S. Pat. No. 1,094,423 to Brandt, which generally teaches a fabric netting structure which attaches to a bird cage by a hook or the like, and which hangs loosely under the cage.", "Litter expelled from the cage is meant to be caught by the fabric underhanging the cage.", "This type of cage attachment has the disadvantage of being difficult to remove, difficult to clean, and is prone to accidental spillage.", "The accidental spillage can occur during cleaning, or debris might escape from the sides of the cage, missing the hanging attachment.", "[0004] Another proposed solution has been a rectangular attachment which wraps around or envelops the sides of a cage, and is held in place by Velcro or elastic.", "This design fails to fully solve the problem of debris being ejected from the cage and into the home environment, however, as there is a gap between the bottom and side of the cage allowing for leakage of debris, particularly liquids.", "[0005] Accordingly, there exists a need for an improved cage guard which minimizes or prevents unwanted matter from being dispelled from a pet cage.", "SUMMARY OF THE INVENTION [0006] The present invention solves the problems noted above by providing a cage guard which is durable, easy to use, and which conforms to both the lower sides and bottom of a pet cage.", "[0007] In one embodiment, the cage guard of the present invention comprises a flexible relatively nonporous bottom designed to conform and snugly fit the bottom of a pet cage.", "The bottom is attached or integrally formed with a flexible relatively nonporous lower side, which is adapted to conform and snugly fit to the lower sides of a pet cage.", "The relatively nonporous lower side is in turn attached or integrally formed with a relatively porous upper side which covers a portion of the sides of the cage above those covered by the relatively nonporous lower side.", "[0008] This design has the advantage of keeping debris from being ejected from lower portions of the cage or slipping through gaps to spill into the home environment.", "The nonporous lower side advantageously keeps very small particles, fluids and excretions within the cage.", "The relatively porous upper side permits easy viewing while keeping larger flying particles within the cage.", "The cage guard is secured to the cage by an elastomeric band attached to the porous upper side.", "The elastomeric band may extend along the entirety of the circumference of the porous upper side, or along less than the entirety provided that elastomeric band provides sufficient force radially inward to hold the cage guard in place.", "[0009] In another embodiment of the present invention, there is provided an animal cage guard which is composed of a flexible nonporous bottom attached directly to porous sides.", "The porous sides are provided with an elastomeric band along an at least an upper portion of the circumference of the porous sides to secure the cage guard to an animal cage.", "The bottom and porous sides are dimensioned such that they are capable of conforming to the shape of the lower portion of the cage.", "Consequently, this embodiment eliminates the nonporous lower side discussed above.", "[0010] Preferably, the materials used to manufacture the cage guard are machine washable.", "Moreover, in some embodiments, it may be desirable to waterproof the nonporous portions, particularly when used with animals likely to expel fluids from lower portions of the cage.", "[0011] The bottom is preferably constructed of a medium to heavy-weight fabric or fabric-like material, such as polycotton, burlap, polyester, polyester blends, trigger poplin, nylon, vinyl, and Gore-tex™.", "The nonporous lower side is preferably constructed of the same material as the bottom.", "The porous side is preferably constructed of a weaved material.", "For example, the porous side may be constructed of mesh netting, nylon tulle, or an elastic mesh.", "It is preferred that the porous side have a mesh gauge having apertures smaller than the largest particle which might be ejected from the cage.", "Depending upon the type of animal kept, the present inventor has found gauge of about 0.1 mm through 3 mm adequate, with 0.2-1 mm being preferred for birds.", "[0012] The elastomeric band used to secure the cage guard to the cage may take the form of an elastic band, a rubber band, or similar elastomeric structure known to those of skill in the art.", "Alternately, the elastomeric band may be eliminated where the porous upper sides are formed of elastomeric materials.", "[0013] In its preferred embodiment, the cage guard of the present invention is used with a bird cage.", "This is because birds tend to reside in the upper portions of their cages, and consequently, the nonporous side will not interfere with most of the viewing of the birds.", "BRIEF DESCRIPTION OF THE DRAWINGS [0014] [0014 ]FIG. 1 is a perspective view showing an animal cage employing the animal cage guard of the present invention on a cage having a square cross-sectional shape.", "[0015] [0015 ]FIG. 2 is a side view showing the animal cage guard of FIG. 1. [0016] [0016 ]FIG. 3 is a top view of the animal cage guard of FIG. 1. [0017] [0017 ]FIG. 4 is a bottom view of the animal cage guard of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0018] The animal cage guard of the present invention is a simple to use barrier which can be fitted to a variety of pet cages for the purpose of catching and holding debris or spillage from lower portions of the cage where such spillage is most likely.", "Furthermore, the cage guard of the present invention is easy to remove and clean.", "It conforms to the cage sides and bottom and therefore minimizes or eliminates gaps through which debris might otherwise slip through.", "This allows the owner to enjoy the pet without the mess and unsanitary conditions that might otherwise occur.", "In addition, the invention is simple and durable, and can be manufactured and sold at a reasonable cost.", "Although described in connection with square cage designs, it should be understood that the invention is not so limited, as it is easily adaptable to other shapes as well as sizes of cages.", "For example, the cage guard of the present invention may be used with cages having oval, triangular, pentagonal, hexagonal, or other geometrical cross-sectional configurations.", "The manner of adapting the present invention to the other embodiments will become apparent to those of skill in the art in view of the teachings herein.", "[0019] Furthermore, the cage guard of the present invention can be used for any animal cage which might have the problem of spillage from the lower sides.", "It is particularly advantageous for a bird cage, and particularly a hanging bird cage or a bird cage which rests on a surface.", "However, the cage guard can be used for a rodent, reptile, rabbit, or any other type of animal cage.", "[0020] An embodiment of cage guard 5 of the present invention is illustrated in FIGS. 1 - 4 .", "Referring to FIG. 1, cage guard 5 is shown fitted over cage 50 .", "Cage 50 may be any conventional wire or barred cage as known to those of skill in the art.", "As shown in FIG. 1, cage 50 has a square cross-sectional shape, and thus a square bottom.", "The sides and bottom of cage guard 5 conform to the lower outer dimensions of cage 50 , and particularly the bottom and lower sides of cage 50 , and thus have a square or cross-sectional shape, as shown in FIGS. 1 - 4 .", "By conform, it is meant that the inner surfaces of cage guard 5 substantially fit to and contact the outer bottom and lower side surfaces of cage 50 .", "In use, cage guard 5 is slipped over the bottom and sides of the cage 50 , and is held in place by means of elastomeric band 40 , as shown in FIG. 1. [0021] Cage guard 5 generally comprises a bottom 10 , a lower side 20 , a porous upper side 30 , and an elastomeric band 40 to secure cage guard 5 to the cage.", "As shown in FIG. 1, cage guard 5 functions to keep food and debris in the cage and to keep liquid and secretions inside the cage, because the lower side 20 is relatively nonporous, and prevents liquids and very small particles from being expelled, while the porous upper side 30 functions to deflect larger size refuse back into the lower portion of the cage, or into a “waste receptacle”", "defined by the sides and bottom portion 10 .", "Advantageously, the home or room in which the pet is kept will be free of debris and waste which would otherwise be expelled from the cage.", "[0022] Referring to FIGS. 1 - 4 , flexible bottom 10 is a particularly advantageous part of the present invention because it conforms to the cage and keeps debris from falling to the floor.", "The term flexible is used to mean that the material chosen for the bottom 10 is capable of conforming to the bottom of the selected cage.", "Bottom 10 is also preferably nonporous.", "The term nonporous is used to mean that the material used for bottom 10 does not have large openings or pores through which animal debris may pass.", "Bottom 10 may be constructed of materials which permit diffusion of gases through bottom 10 , such as air.", "Bottom 10 may also be constructed of materials that will pass liquids, although in most embodiments of the present invention, it is preferred that bottom 10 prevent or minimize liquid flow therethrough and thus be waterproofed.", "[0023] In a preferred embodiment, bottom 10 is selected in view of the type of refuse which a particular animal might expel from the bottom side portions of a cage.", "For example, birds tend to eject droppings and water from the bottom portions of their cages, and portion 10 is selected to prevent such refuse from being expelled.", "Particularly suitable materials for construction of bottom 10 include medium to heavy fabrics, either natural or synthetic.", "Such a fabric may include polycotton, burlap, polyester, polyester blends, trigger poplin, nylon, vinyl, denim, spandex, and waterproof materials such as GORETEX™, as well as other similar materials known to those of skill in the art.", "[0024] In some embodiments, it may be desirable to construct bottom 10 of waterproof materials.", "This embodiment is particularly advantageous where it is expected that water or other fluids may be expelled from the cage.", "When bottom 10 is constructed of waterproof materials and cage guard 5 is fitted over the cage, expelled liquids will be trapped within the region defined by the interior of bottom 10 and lower side 20 , which function as a waterproof waste receptacle.", "Bottom 10 may be waterproofed in a variety of ways.", "For example, bottom 10 may be treated chemically to waterproof it, or it may be constructed of waterproof materials.", "This may include the addition of a second layer of waterproof material lining bottom 10 and lower side 20 .", "Waterproof materials may include flexible plastics and other synthetics, as known to those of skill in the art.", "[0025] In the embodiment shown in FIGS. 1 - 4 , bottom 10 is attached to or integrally formed with lower side 20 .", "In a preferred embodiment, side portion 20 is relatively nonporous, and is preferably constructed of materials similar to those used for bottom 10 .", "Side 20 may also be constructed of translucent materials, such as plastics, to permit easier viewing of the lower portions of the cage.", "In some embodiments, it may also be desirable to construct bottom 10 out of different materials than lower side 20 .", "[0026] Bottom 10 is preferably be attached to nonporous lower side 20 in such a way that there is no gap therebetween.", "Such attachment may comprise sewing, fusing, or adhesively bonding the portions together, or other attachment means known to those of skill in the art.", "[0027] As is shown in FIGS. 1 - 4 , porous upper side 30 is attached to lower side 20 .", "Such attachment can be by any means known to those of skill in the art, and particularly those noted above.", "Porous side 30 of the present invention offers the ability to view the animal without obstruction which might be created by the nonporous sides if the nonporous sides are constructed of opaque materials.", "Porous side 30 also permits air to freely flow therethrough, for the enjoyment and health of the animal.", "Porous side 32 may have a variety of gauges.", "Gauge refers to the spaces or pores between the fibers of the mesh.", "The mesh is preferably a small enough gauge that excretions will be contained within the cage or it can be of a large mesh to allow for better viewing.", "Porous side 30 can be chosen in a variety of tightness of weave or gap such that it will keep different sized flying debris, or even excretions in the cage without obstructing the view.", "In one embodiment, porous side 30 is made up of a large weave fabric or net, having openings of from about 2 mm-3 mm.", "This size of opening would be sufficient to keep most cage debris from being ejected from the cage, such as a bird cage, but will not prevent liquids from being expelled.", "Porous side 30 is preferably made up of a material such as nylon mesh net or nylon tulle which is stiff yet flexible enough to fit to the sides of the cage.", "In some embodiments, porous side 30 may be constructed of elastomeric materials which secure cage guard 5 to the cage without need for band 40 .", "[0028] In one preferred embodiment the gauge of the porous side 30 is smaller than the smallest solid particle that may likely exit the cage at the particular point where the gauge is positioned.", "Thus, for example, if an animal tends to expel larger size refuse from upper portions of the cage and smaller size refuse from lower portions, the gauge of the lower portions may be selected to be smaller than that of the upper portions.", "Advantageously, the larger gauge of the upper portions facilitates viewing of the animal.", "Preferably, the porous side 30 is made of a material which is machine washable to allow for easy clean-up.", "[0029] Porous side portion 30 may have an elastomeric band 40 along a portion of the circumference of the porous side 30 or along the entire circumference.", "Band 40 secures cage guard 5 to cage 50 .", "Furthermore, band 40 is preferably selected to allow for easy removal and mounting of the cage guard, and to permit the side portions 20 and 30 to conform closely to the cage without gaps.", "[0030] Band 40 may be made of any substance that allows for the above conditions.", "One class of materials found suitable are elastomeric materials.", "These may include an elastic band, a rubber band, or spandex.", "Alternatively, separate band 40 may be eliminated if porous side 30 are made of a stretchable material which can, in and of itself, conform to the cage and hold the cage guard in place.", "[0031] In an alternate embodiment, lower side 20 is eliminated, and bottom 10 is attached directly to porous upper side 30 , such that the lower sides of the cage are encompassed within conforming porous upper side 30 .", "In this embodiment, porous side 30 may have lower regions of small gauge, as for example 2-3 inches along the bottom of a cage, and open regions with larger gauge.", "This embodiment is advantageous for pet cages housing pets which spend most of their time in lower portions of the cage, such as rodents, because the porous side 30 permits easier viewing of the pet.", "[0032] One unique advantage of the cage guard of the present invention is its ability to conform to the lower portions of the pet cage.", "As described above, this is accomplished by choosing materials which are flexible enough to be pulled over the cage, and by dimensioning the cage guard so that its cross-sectional shape and area are within a range sufficient to permit the cage guard to conform.", "For example, if a cage has a square cross-sectional shape with sides of 12 inches, bottom 10 preferably has a square cross-sectional shape, and sides of slightly larger than 12 inches.", "The height of sides 20 and 30 can be varied as needed to accommodate the animal kept.", "For birds, it is preferred that side 20 have a height of 2-5 inches, and side 30 a height of 5-10 inches, although these are not limiting values and can be varied as desired to optimize viewing enjoyment and still prevent waste expulsion.", "Where elastomeric band 40 is used, it is preferred that it have an unstretched circumference slightly smaller than the circumference of the cage, and stretched circumference larger than the circumference of the cage, so that a radial inward force is generated when the cage guard 5 is fixed on a cage, to hold the cage guard in place.", "[0033] Alternatively, the cage guard of the present invention may be of a different cross-sectional shape or larger area, but still conform to the cage by means of fasteners which can be adjusted to conform the cage guard to the cage.", "In one embodiment these additional fasteners can be velcro fasteners, positioned at points along the sides of the cage guard to eliminate slack.", "For example, Velcro hooks can be provided near the edges of the lower sides on upper sides, with the mating Velcro piece attached to the adjacent side near the edge, such that the two mating Velcro pieces can be secured to remove slack from the cage guard.", "Hooks, buttons, snap fasteners and the like might also be used in place of Velcro.", "These fasteners can be incorporated into various points of sides 20 and 30 to allow for tightening the sides 20 and 30 to the cage at the corners or elsewhere.", "[0034] The cage guard of the present invention can be constructed in such a way that it is inexpensive to produce yet durable.", "It can also be constructed in such a way that it is machine washable and thus easy to clean and keep sanitary.", "Lastly, it can be constructed in such a way that it will keep debris and excretions from exiting the cage and depositing on walls, floors, and furniture thus allowing the user to enjoy the animal without undue or unsanitary discomfort.", "[0035] From the foregoing description, additional advantages and novel features or alternatives will be apparent to one of skill in the art.", "[0036] It should be understood that changes may be made in the construction and in the combination and arrangement of the several parts, provided that such changes fall within the scope of the appended claims." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a low noise level automotive internal combustion engine, and more particularly to the engine equipped with a bearing beam structure for supporting a crankshaft in a manner to improve the mechanical strength of the cylinder block. 2. Description of the Prior Art In connection with engine noise, noise emitted from a cylinder block skirt section and an oil pan is mainly caused by the vibration of a cylinder block itself. In order to reduce such vibration noise, it would appear sufficient to suppress the vibration, due to explosion torque, applied to a crankshaft by increasing the rigidity of the cylinder block. However, this unavoidably leads to an increase in cylinder block wall thickness and accordingly to a great increase in engine weight, thereby giving rise to new problems such as reduced fuel economy. In view of this, a variety of propositions have been made to improve the rigidity of the cylinder block while suppressing the increase in cylinder block weight. Of these propositions, attention has been paid to the employment of a bearing beam structure which securely connects a plurality of bearing caps for supporting the crankshaft, in order to improve the mechanical strength of bearing caps and engine parts associated with them. BRIEF SUMMARY OF THE INVENTION In accordance with the present invention, an internal combustion engine comprises a cylinder block which is rigidly connected to a transmission and has cylinder bores and bearing sections. A bearing beam structure is secured to the bottom part of the cylinder block and includes main bearing cap sections each of which associates with a cylinder block bearing section to rotatably support the journal of a crankshaft. The bearing beam structure further includes first and second beam sections which are disposed to securely connect the main bearing cap sections with each other. The first and second beam sections extend parallel with the axis of the crankshaft, and are located spaced from each other and along the respective opposite portions of each bearing cap section. The first and second beam sections are rigidly connected respectively through first and second connecting sections with the transmission. With the thus arranged engine, the bearing beam structure is prevented from vibrating in the crankshaft axis direction, while contributing to an improvement in rigidity of a whole power unit including the transmission, thereby effectively decreasing vibration noises emitted from various engine parts. BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of the internal combustion engine according to the present invention will be more appreciated from the following description taken in conjunction with the accompanying drawings in which like reference numerals and characters designate like parts and elements, in which: FIG. 1 is a front elevation of a conventional internal combustion engine; FIG. 2 is a vertical sectional view taken in the direction of arrows substantially along the line II--II of FIG. 1; FIG. 3 is a perspective view of a conventional bearing beam structure used in the engine of FIG. 1; FIG. 4 is a side elevation of a preferred embodiment of an internal combustion engine in accordance with the present invention; FIG. 5 is a cross-sectional view taken in the direction of arrows substantially along the line V--V of FIG. 4; and FIG. 6 is a cross-sectional view taken in the direction of arrows substantially along the line of VI--VI of FIG. 5. DETAILED DESCRIPTION OF THE INVENTION To facilitate understanding the invention, a brief reference will be made to an engine block 1 of a conventional automotive internal combustion engine, depicted in FIGS. 1 to 3. Referring to FIGS. 1 and 2, the engine block 1 includes a cylinder block 2, and a bearing beam structure 3 secured to the bottom part of the cylinder block 2 by means of bolts. The bearing beam structure 3 has a plurality of main bearing cap sections 4 each of which associates with a bearing sections 5 or a main bearing bulkhead of the cylinder block 2, as shown in FIG. 3. The thus associated bearing cap section 4 and cylinder block bearing section 5 rotatably support the journal of a crankshaft (not shown). The bearing cap sections 4 are securely or integrally connected with each other through a beam section 6 extending along the axis of the crankshaft, so that the rigidity of the cylinder block 2 can be increased. Therefore, the cylinder block 2 is improved in flexural rigidity against the flexural vibration indicated in phantom in FIG. 1, and the bearing cap sections 4 are also improved in flexural rigidity against the vibration in the axial direction of the crankshaft or in the forward-and-rearward direction. This vibration so acts on each bearing cap section as to cause it to come down. As discussed above, the cylinder block 2 and the bearing cap sections 4 are improved in their mechanical strength. However, it has been confirmed that a desired engine noise reduction cannot be attained. In this connection, my recent experiments have revealed that the lateral vibration of the cylinder block skirt section 7 is induced by the movements of bearing cap sections 4 and the bearing bulkheads 5 due to their torsional vibration around the crankshaft axis and flexural vibration in the right-and-left direction in plan or in the direction indicated by the arrows in FIG. 3. Such movements are combined with each other and excite the vibration of the cylinder block skirt section 7 and the engine oil pan. In order to suppress such vibrations, the above-mentioned conventional bearing beam structure 3 is not so effective and therefore is low in noise reduction effect for the weight increase thereof. In view of the above description of the automotive internal combustion engine provided with the conventional bearing beam structure, reference is now made to FIGS. 4 to 6, wherein a preferred embodiment of an internal combustion engine of the present invention is illustrated by the reference numeral 10. The engine 10 in this embodiment is for an automotive vehicle and comprises a cylinder block 12 which is formed with a plurality of cylinder barrels 14 each of which defines therein a cylinder bore (no numeral). The cylinder block 12 includes a skirt section 16 which is bulged outwardly and extends downwardly to define thereinside an upper part of a crankcase (no numeral). The skirt section 16 is integrally connected through a lower block deck 18 with the cylinder barrels 14. A plurality of main bearing bulkheads 20 are parallelly disposed inside of the the skirt section 16. Each bearing bulkhead 20 is located below and connected to a portion between the adjacent two cylinder barrels 14. The bearing bulkhead 20 is integrally connected at its top part with the lower block deck 18 and at its side parts with the inner wall of the skirt section 16. Each bearing bulkhead 20 is provided at its bottom central portion with a bearing section 22 for rotatably receiving the journal of a crankshaft (no numeral). A bearing beam structure 26 is securely connected to the bottom section of the cylinder block 12 and includes a plurality of main bearing cap sections 28. Each bearing cap section 28 is secured at its top portion onto each bearing bulkhead 20 by means of cap bolts 30 so as to associate with the bearing section 20a of the bearing bulkhead 20, thereby defining a cylindrical bore 24 in which the journal of the crankshaft is rotatably supported. In this instance, the bearing cap section 28 is generally rectangular as viewed from the direction of the axis of the crankshaft or of the bore 24. The bearing cap sections 28 are connected with each other through two beam sections or members 32A, 32B each of which is, in this instance, integral with the bearing cap sections 28. The two beam sections 32A, 32B extend parallel with the crankshaft axis, and are positioned respectively at and along the bottom opposite corners of the bottom portion of each bearing cap section 28 so that each beam section is perpendicular to each bearing cap. Additionally, the beam sections 32A, 32B are located symmetrical with each other with respect to a vertical plane (not shown) containing the crankshaft axis and parallel with the axes (not shown) of the cylinder bores. As best shown in FIG. 4, the cylinder block 12 is rigidly connected through an end plate 34 with a transmission 36. More specifically, the cylinder block skirt section 16 is integrally provided at its rear end part with oppositely disposed projections 16a which extend laterally outwardly. A bell housing 36a of the transmission 36 is connected at its upper-half with the cylinder block skirt section rear end through the skirt section projections 16a by means of bolts 38. Additionally, in this embodiment, the respective rear end of the beam sections 32A, 32B extend obliquely and downward to form extended or connecting sections 40A, 40B which are continuous from and integral with the beam sections 32A, 32B, respectively. The extended sections 40A, 40B are positioned generally symmetrical with each other relative to the vertical plane containing the crankshaft axis. Each extended section 40A, 40B has a contacting surface corresponding to the rear end surface of the cylinder block 12 to which the end plate 34 contacts, and therefore the extended section contacting surface also contacts the end plate 34. Each beam section 32A, 32B is rigidly connected through this extended section 40A, 40B with the lower part of the transmission bell housing 36a by means of bolts 42. Furthermore, in this instance, only the bearing cap section 28 positioned at the rear-most part of the bearing beam structure 26 is formed to be semicircular as viewed from the direction of the crankshaft axis and integrally provided along its outer periphery with a semicircular oil pan installation seat 44 to which an oil pan 46 is securely attached in order to form the crankcase which is completely closed at its rear-most end. The rear-most bearing cap section 28 is provided also with an oil seal installation seat 48 on which an oil seal for the crankshaft is securely supported or carried. With the thus arranged internal combustion engine, by virtue of the parallelly disposed beam sections 32A, 32B, the bearing cap sections 28 are increased in strength against its coming-down vibration in the crankshaft axis direction and the torsional strength around the crankshaft axis, and additionally improved in the flexural strength around the cylinder bore axis. This greatly suppresses the torsional vibration and the flexural vibration in the right-and-left direction of the main bearing bulkheads 20 rigidly connected with the bearing cap sections 28, thereby effectively preventing the cylinder block skirt section 16 from experiencing open-and-close vibration (membrance vibration). The vibration nodes of the cylinder block skirt exist in locations where the main bearing bulkhead 20 is connected to the cylinder block skirt section 16. Besides, the bearing beam structure 26 is rigidly connected at its lower part with the transmission 36, and therefore the bearing beam structure 26 is effectively prevented from vibration in the crankshaft axis direction or in the forward-and-rearward direction, thereby largely suppressing noise. Moreover, the cylinder block 12, the bearing beam structure 26 and the transmission 36 are rigidly connected with each other. As a result of these facts, in combination with the effect of the above-mentioned parallelly disposed beam sections 32A, 32B, the entire engine is remarkedly improved in rigidity, thereby effectively suppressing noise generation from the various parts of the engine. It is to be noted that the bearing beam structure 26 is connected to the transmission 36 through two foot-like sections (extended sections) 40A, 40B, which is particularly effective for suppressing the torsional vibration of the cylinder block 12. Thus, engine noise due the above-mentioned various vibrations is greatly lowered. Moreover, in this instance, since the oil pan installation seat 44 and the crankshaft oil seal installation seat 48 are formed integrally with the bearing beam structure 26, the construction of sealing devices are simplified, thereby facilitating machining and assembly operation. As is appreciated from the above, according to the present invention, the two parallelly disposed beam sections of the bearing beam structure extend to be connected with the transmission by means of bolt connection. Accordingly, the rigidity of the engine entire is further improved, thereby greatly reducing engine noise.
An internal combustion engine comprises a cylinder block rigidly connected to a transmission and having cylinder bores and bearing sections; and a bearing beam structure including main bearing cap sections each associating with each cylinder block bearing section to rotatably support a crankshaft, first and second beam sections securely connecting the main bearing cap sections with each other and extending parallelly with the crankshaft axis, the first and second beam sections being located spaced from each other and along the respective opposite side portions of each bearing cap section, and first and second connecting sections respectively integral with the first and second beam sections and being rigidly connected to the transmission, thereby preventing the bearing beam structure from its axial vibration while contributing to an improvement in rigidity of a power unit entire including the transmission.
Briefly summarize the main idea's components and working principles as described in the context.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention This invention relates to a low noise level automotive internal combustion engine, and more particularly to the engine equipped with a bearing beam structure for supporting a crankshaft in a manner to improve the mechanical strength of the cylinder block.", "Description of the Prior Art In connection with engine noise, noise emitted from a cylinder block skirt section and an oil pan is mainly caused by the vibration of a cylinder block itself.", "In order to reduce such vibration noise, it would appear sufficient to suppress the vibration, due to explosion torque, applied to a crankshaft by increasing the rigidity of the cylinder block.", "However, this unavoidably leads to an increase in cylinder block wall thickness and accordingly to a great increase in engine weight, thereby giving rise to new problems such as reduced fuel economy.", "In view of this, a variety of propositions have been made to improve the rigidity of the cylinder block while suppressing the increase in cylinder block weight.", "Of these propositions, attention has been paid to the employment of a bearing beam structure which securely connects a plurality of bearing caps for supporting the crankshaft, in order to improve the mechanical strength of bearing caps and engine parts associated with them.", "BRIEF SUMMARY OF THE INVENTION In accordance with the present invention, an internal combustion engine comprises a cylinder block which is rigidly connected to a transmission and has cylinder bores and bearing sections.", "A bearing beam structure is secured to the bottom part of the cylinder block and includes main bearing cap sections each of which associates with a cylinder block bearing section to rotatably support the journal of a crankshaft.", "The bearing beam structure further includes first and second beam sections which are disposed to securely connect the main bearing cap sections with each other.", "The first and second beam sections extend parallel with the axis of the crankshaft, and are located spaced from each other and along the respective opposite portions of each bearing cap section.", "The first and second beam sections are rigidly connected respectively through first and second connecting sections with the transmission.", "With the thus arranged engine, the bearing beam structure is prevented from vibrating in the crankshaft axis direction, while contributing to an improvement in rigidity of a whole power unit including the transmission, thereby effectively decreasing vibration noises emitted from various engine parts.", "BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of the internal combustion engine according to the present invention will be more appreciated from the following description taken in conjunction with the accompanying drawings in which like reference numerals and characters designate like parts and elements, in which: FIG. 1 is a front elevation of a conventional internal combustion engine;", "FIG. 2 is a vertical sectional view taken in the direction of arrows substantially along the line II--II of FIG. 1;", "FIG. 3 is a perspective view of a conventional bearing beam structure used in the engine of FIG. 1;", "FIG. 4 is a side elevation of a preferred embodiment of an internal combustion engine in accordance with the present invention;", "FIG. 5 is a cross-sectional view taken in the direction of arrows substantially along the line V--V of FIG. 4;", "and FIG. 6 is a cross-sectional view taken in the direction of arrows substantially along the line of VI--VI of FIG. 5. DETAILED DESCRIPTION OF THE INVENTION To facilitate understanding the invention, a brief reference will be made to an engine block 1 of a conventional automotive internal combustion engine, depicted in FIGS. 1 to 3.", "Referring to FIGS. 1 and 2, the engine block 1 includes a cylinder block 2, and a bearing beam structure 3 secured to the bottom part of the cylinder block 2 by means of bolts.", "The bearing beam structure 3 has a plurality of main bearing cap sections 4 each of which associates with a bearing sections 5 or a main bearing bulkhead of the cylinder block 2, as shown in FIG. 3. The thus associated bearing cap section 4 and cylinder block bearing section 5 rotatably support the journal of a crankshaft (not shown).", "The bearing cap sections 4 are securely or integrally connected with each other through a beam section 6 extending along the axis of the crankshaft, so that the rigidity of the cylinder block 2 can be increased.", "Therefore, the cylinder block 2 is improved in flexural rigidity against the flexural vibration indicated in phantom in FIG. 1, and the bearing cap sections 4 are also improved in flexural rigidity against the vibration in the axial direction of the crankshaft or in the forward-and-rearward direction.", "This vibration so acts on each bearing cap section as to cause it to come down.", "As discussed above, the cylinder block 2 and the bearing cap sections 4 are improved in their mechanical strength.", "However, it has been confirmed that a desired engine noise reduction cannot be attained.", "In this connection, my recent experiments have revealed that the lateral vibration of the cylinder block skirt section 7 is induced by the movements of bearing cap sections 4 and the bearing bulkheads 5 due to their torsional vibration around the crankshaft axis and flexural vibration in the right-and-left direction in plan or in the direction indicated by the arrows in FIG. 3. Such movements are combined with each other and excite the vibration of the cylinder block skirt section 7 and the engine oil pan.", "In order to suppress such vibrations, the above-mentioned conventional bearing beam structure 3 is not so effective and therefore is low in noise reduction effect for the weight increase thereof.", "In view of the above description of the automotive internal combustion engine provided with the conventional bearing beam structure, reference is now made to FIGS. 4 to 6, wherein a preferred embodiment of an internal combustion engine of the present invention is illustrated by the reference numeral 10.", "The engine 10 in this embodiment is for an automotive vehicle and comprises a cylinder block 12 which is formed with a plurality of cylinder barrels 14 each of which defines therein a cylinder bore (no numeral).", "The cylinder block 12 includes a skirt section 16 which is bulged outwardly and extends downwardly to define thereinside an upper part of a crankcase (no numeral).", "The skirt section 16 is integrally connected through a lower block deck 18 with the cylinder barrels 14.", "A plurality of main bearing bulkheads 20 are parallelly disposed inside of the the skirt section 16.", "Each bearing bulkhead 20 is located below and connected to a portion between the adjacent two cylinder barrels 14.", "The bearing bulkhead 20 is integrally connected at its top part with the lower block deck 18 and at its side parts with the inner wall of the skirt section 16.", "Each bearing bulkhead 20 is provided at its bottom central portion with a bearing section 22 for rotatably receiving the journal of a crankshaft (no numeral).", "A bearing beam structure 26 is securely connected to the bottom section of the cylinder block 12 and includes a plurality of main bearing cap sections 28.", "Each bearing cap section 28 is secured at its top portion onto each bearing bulkhead 20 by means of cap bolts 30 so as to associate with the bearing section 20a of the bearing bulkhead 20, thereby defining a cylindrical bore 24 in which the journal of the crankshaft is rotatably supported.", "In this instance, the bearing cap section 28 is generally rectangular as viewed from the direction of the axis of the crankshaft or of the bore 24.", "The bearing cap sections 28 are connected with each other through two beam sections or members 32A, 32B each of which is, in this instance, integral with the bearing cap sections 28.", "The two beam sections 32A, 32B extend parallel with the crankshaft axis, and are positioned respectively at and along the bottom opposite corners of the bottom portion of each bearing cap section 28 so that each beam section is perpendicular to each bearing cap.", "Additionally, the beam sections 32A, 32B are located symmetrical with each other with respect to a vertical plane (not shown) containing the crankshaft axis and parallel with the axes (not shown) of the cylinder bores.", "As best shown in FIG. 4, the cylinder block 12 is rigidly connected through an end plate 34 with a transmission 36.", "More specifically, the cylinder block skirt section 16 is integrally provided at its rear end part with oppositely disposed projections 16a which extend laterally outwardly.", "A bell housing 36a of the transmission 36 is connected at its upper-half with the cylinder block skirt section rear end through the skirt section projections 16a by means of bolts 38.", "Additionally, in this embodiment, the respective rear end of the beam sections 32A, 32B extend obliquely and downward to form extended or connecting sections 40A, 40B which are continuous from and integral with the beam sections 32A, 32B, respectively.", "The extended sections 40A, 40B are positioned generally symmetrical with each other relative to the vertical plane containing the crankshaft axis.", "Each extended section 40A, 40B has a contacting surface corresponding to the rear end surface of the cylinder block 12 to which the end plate 34 contacts, and therefore the extended section contacting surface also contacts the end plate 34.", "Each beam section 32A, 32B is rigidly connected through this extended section 40A, 40B with the lower part of the transmission bell housing 36a by means of bolts 42.", "Furthermore, in this instance, only the bearing cap section 28 positioned at the rear-most part of the bearing beam structure 26 is formed to be semicircular as viewed from the direction of the crankshaft axis and integrally provided along its outer periphery with a semicircular oil pan installation seat 44 to which an oil pan 46 is securely attached in order to form the crankcase which is completely closed at its rear-most end.", "The rear-most bearing cap section 28 is provided also with an oil seal installation seat 48 on which an oil seal for the crankshaft is securely supported or carried.", "With the thus arranged internal combustion engine, by virtue of the parallelly disposed beam sections 32A, 32B, the bearing cap sections 28 are increased in strength against its coming-down vibration in the crankshaft axis direction and the torsional strength around the crankshaft axis, and additionally improved in the flexural strength around the cylinder bore axis.", "This greatly suppresses the torsional vibration and the flexural vibration in the right-and-left direction of the main bearing bulkheads 20 rigidly connected with the bearing cap sections 28, thereby effectively preventing the cylinder block skirt section 16 from experiencing open-and-close vibration (membrance vibration).", "The vibration nodes of the cylinder block skirt exist in locations where the main bearing bulkhead 20 is connected to the cylinder block skirt section 16.", "Besides, the bearing beam structure 26 is rigidly connected at its lower part with the transmission 36, and therefore the bearing beam structure 26 is effectively prevented from vibration in the crankshaft axis direction or in the forward-and-rearward direction, thereby largely suppressing noise.", "Moreover, the cylinder block 12, the bearing beam structure 26 and the transmission 36 are rigidly connected with each other.", "As a result of these facts, in combination with the effect of the above-mentioned parallelly disposed beam sections 32A, 32B, the entire engine is remarkedly improved in rigidity, thereby effectively suppressing noise generation from the various parts of the engine.", "It is to be noted that the bearing beam structure 26 is connected to the transmission 36 through two foot-like sections (extended sections) 40A, 40B, which is particularly effective for suppressing the torsional vibration of the cylinder block 12.", "Thus, engine noise due the above-mentioned various vibrations is greatly lowered.", "Moreover, in this instance, since the oil pan installation seat 44 and the crankshaft oil seal installation seat 48 are formed integrally with the bearing beam structure 26, the construction of sealing devices are simplified, thereby facilitating machining and assembly operation.", "As is appreciated from the above, according to the present invention, the two parallelly disposed beam sections of the bearing beam structure extend to be connected with the transmission by means of bolt connection.", "Accordingly, the rigidity of the engine entire is further improved, thereby greatly reducing engine noise." ]
CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 10/490,973 filed Sep. 13, 2004. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not applicable. THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT Not applicable. REFERENCE TO SEQUENCE LISTING Not applicable. FIELD OF THE INVENTION The present invention is directed to radial block copolymer compositions and pressure-sensitive adhesive compositions based thereon. The pressure-sensitive adhesives are particularly useful in label and tape manufacture. BACKGROUND OF THE INVENTION Radial block copolymers are known and it is also known that during their manufacture up to 20 wt % of the diblock copolymers remain unreacted and are present as diblock copolymer material. These low diblock content radial copolymers have been proposed as components in pressure-sensitive adhesives, where they are used to make during label manufacture, a laminate of a face stock, pressure-sensitive adhesive layer, and a release liner, such as silicone-coated paper, which is passed through an apparatus that converts the laminate into commercially useful labels and label stock. The converting operation processes involve printing, die-cutting, and matrix stripping to leave labels on a release liner, marginal hole punching, perforating, fan folding, guillotining and the like. It is important that the cutting action breaks the face stock and adhesive layer, but does not indent the release liner. Producing a series of labels on a backing sheet involves cutting around the label and removing the material between two labels (the matrix) while leaving the label itself attached to the backing sheet. It is important that the die-cutting machine make a clean break at operating speeds. The adhesive with the copolymer of low diblock content is formulated to have the desired viscoelastic and adhesive properties so that it can be applied to the release liner or the face-stock back, and will remain on the label after stripping and will have the required adhesion. But these are properties that make the adhesive film difficult to cut or break. These properties make die-cutting difficult and inconsistent, causing the adhesive lends to form adhesive strings and deposits on the cutting blade. FIG. 1 illustrates a typical die-cutting process. Die-cutting involves cutting the laminate through to the release liner face. Other procedures involve cutting completely through the label laminate and include hole punching, perforating, and guillotining, particularly on flat sheets. The cost of converting a laminate into a finished product, such as a label, is a function of the various processing operations' rates. Line speed depends on whether a printing step is involved. If there is no printing as with, for example, computer labels, speeds can reach 300 meters/minute. If label printing is involved, then speeds of 50-100 meters/minute are typical. While the nature of all laminate layers impact convertibility cost, the adhesive layer can limit convertibility ease. The adhesive layer's viscoelastic nature causes this limitation—in particular its high elasticity prevents it from flowing away from the cut line during die-cutting and also promotes its transfer to cutting blades during cutting. High adhesive elasticity also causes adhesive stringiness, which hinders matrix stripping as the unwanted facing material is removed after die-cutting. High elasticity also promotes adhesive layer reconnection after the layer is severed. Achieving good convertibility does not necessarily coincide with achieving excellent adhesive performance. Adhesives must be formulated to fit needs, and important properties include peel adhesion, tack, shear, and viscosity at various temperatures and adhesion on various substrates such as polymers, papers, glasses, and steels. Good, general-purpose adhesives may exhibit poor convertibility simply because the adhesive is difficult to cleanly sever. The adhesive may stick to a die or blade. As previously discussed in label manufacture, die-cutting and matrix stripping operations occur at speeds from 5-300 meters per minute, typically 50-100 meters per minute, if printing is involved. Within a range of speeds, use of a particular adhesive may result in breaking the matrix despite the fact that successful matrix stripping can occur at speeds on either side of the breaking speed. One goal is to provide adhesive systems where the adhesive has good die-cutting performance and where the matrix can be successfully stripped over the entire operating speed range. Typical label adhesives are produced from acrylic polymer emulsions, which may be tackified by hydrocarbon or natural-resin tackifiers. While these have good die-cutting performance, they require handling large volumes of liquid and subsequent liquid removal. Accordingly, adhesives applied as hot melts would be preferred. At low temperature, acrylic-based adhesives perform poorer than hot-melt systems. Moreover, hot melts can be used at faster line application speeds in a broader temperature range, have more aggressive tack, and can be used under humid conditions. It is however important that the adhesive has desired theological properties both for processability such as coating and at end use temperature. Hot-melt pressure-sensitive adhesive systems are well known and consist of tackified thermoplastic elastomers such as styrenic block copolymers together with tackifying resin(s) and generally some plasticizing oil, an antioxidant and optionally fillers. Styrenic block copolymers containing polystyrene and polybutadiene blocks and/or polyisoprene blocks are particularly useful. These materials are generally available as pure triblocks, (sometimes referred to as SIS and SBS copolymers), and diblocks (sometimes referred to as SI and SB copolymers). The materials are also available as mixtures of diblock and triblock materials (sometimes referred to as SIS+SI and SIS+SB). Examples of these materials are the Vector materials marketed by Dexco and the Kraton D materials marketed by Kraton Polymers. Radial block copolymers have also been proposed. It is known to use diblock/triblock blends as the elastomeric component in hot-melt pressure-sensitive adhesives. It is further known that adhesive properties and viscosity can be controlled by varying the diblock-to-triblock ratio, varying the styrene content, varying the polymer molecular weight, and varying the block molecular weights within the polymers. The melt viscosity can also be controlled by the addition of plasticizing oils and varying the molecular weight of the polymers. Examples of materials that have been used are Kraton D 1113, containing 16% styrene and 56% diblock; Quintac 3433, marketed by Nippon Zeon, containing 55% diblock and 17% styrene; Vector 4114, containing 42% diblock and 17% styrene; and Vector 4113 containing 20% diblock and 17% styrene. Vector 4114 and Vector 4113 are Dexco products. While these materials have good adhesive properties when tackified and can be used in hot melts for label production, they do not have optimum die-cutting properties. Furthermore, their balance of adhesive properties is not optimum. U.S. Pat. No. 5,663,228 concerns improving label adhesive die-cuttability. But the proposed solution is different and more complicated than the present invention and requires the use of two particular block copolymer resins having certain glass-transition temperatures and the choice of a tackifying resin that, when mixed with the two particular block copolymers, increases the difference between the two block copolymers' glass transition temperatures. U.S. Pat. No. 5,663,228 also does not appreciate the importance of the adhesive's elastomeric behavior under die-cutting conditions. Examples of styrenic copolymers that are used in the adhesive mixtures of U.S. Pat. No. 5,663,228 are Finaprene 1205 available from AtoFina and Kraton 1107 available from Kraton Polymers. U.S. Pat. No. 5,412,032 concerns linear SIS triblock/diblock copolymers that can be used in labels to improve die-cutting. This is accomplished using block copolymers with a styrene content from 18 to 24 wt %, a polystyrene block molecular weight from 25,000 to 35,000 an overall molecular weight of above 280,000 up to 520,000 and a coupling efficiency of 20% to 40%. The coupling efficiency corresponds to the percentage of triblock material in the overall block copolymer. PCT Patent applications PCT/US01/20671 and PCT/US01/20609 describe the use of certain diblock/triblock blends and the use of tetrablock and pentablock copolymers in label adhesives to improve die-cutting performance. It is also known to use radial block copolymers in hot melt adhesives. For example, U.S. Pat. Nos. 5,194,500 and 5,750,607 relate to styrene-isoprene three-arm block copolymers and their use in adhesives. These three-arm radial copolymers are available as Kraton 1124 from Kraton Polymers and Quintac 3450 and Quintac 3460C from Nippon Zeon. International Patent Publications WO 92/20725 and WO 95/14727 are concerned with radial block copolymers comprising polystyrene block segments and diene block segments, the diene block segment is preferably predominately polyisoprene block containing a small amount of butadiene at the end of the diene block to ensure multi arm coupling. These publications also disclose the use of these polymers in hot melt adhesive systems. WO 92/20725 is primarily concerned with the use of such polymers in adhesives used in disposable articles. WO 95/14727 is concerned with achieving optimum balance between high holding power and low melt viscosity of the adhesives. European Patent Application 0798358 A1 is concerned with hot melt adhesives, particularly hot melt adhesives for labeling which have a reduced viscosity. The adhesives have a low diblock content and we have found that this results in an adhesive that is too cohesive and has high elasticity which is detrimental for die cuttability as is shown in Comparative Example 1 which is based on the radial polymer DPX-551 mentioned in European Patent Application 0798358 A1 as a suitable polymer for use in its adhesive formulations. The radial block copolymers of WO 95/14727 are characterised by the formula: (pS-pI-pB) n X  (1) wherein pS is polystyrene, pJ is polyisoprene, pB is polybutadiene, X is a residue of a multifunctional coupling agent used in the production of the radial block copolymer, and n is a number greater than or equal to 3 and representative of the number of branches appended to X. According to WO 95/14727 the number n is predominately 4. The molecular weight of the pS block of the radial block copolymer is between about 10,000 to about 15,000 g/mole, preferably from about 12,000 to about 14,000 g/mole. The pJ-pB block preferably has a total average number molecular weight (polystyrene equivalent molecular weight) ranging from about 40,000 to about 130,000 g/mole, preferably from about 50,000 to about 115,000 g/mole. The overall number average molecular weight (polystyrene equivalent) of the radial block copolymer ranges from about 200,000 to about 400,000 g/mole, preferably from about 225,000 to about 360,000 g/mole, and the polystyrene block pS component is present in an amount of at least about 14 to about 24 parts, preferably from about 15 to about 22 parts, per 100 parts by weight of the radial block copolymer. The radial block copolymers of WO 95/14727 are thus constituted of polystyrene block segments and polydiene block segments in accordance with formula (1). The copolymers may be random, tapered, block or a combination of these, provided that the polybutadiene segment acts as the terminus segment of the polydiene block so that it may react with the coupling agent. The other end block of the polymer is polystyrene. The pS segment is generally prepared by sequentially polymerizing styrene. In accordance with formula (1), isoprene is employed to make the pJ segments, the (pS-pJ) polymer chains being formed by sequential polymerization of isoprene with the pS. The pS-pJ-pB-Li polymer chains are then formed by the sequential polymerization of living pS-pI-Li polymer chains with butadiene. The radial or multiblock (pS-pI-pB) n X copolymers are correspondingly made by coupling the pS-pJ-pB-Li living polymer chains with a multi- or tetra-functional coupling agent, such as SiCl 4 . Thus, the styrene is polymerized to form pS, the isoprene is then introduced to form pS-pI, the butadiene is then introduced to form pS-pI-pB, and the pS-pJ-pB chains are then coupled with the tetrafunctional coupling agent to form the (pS-pI-pB) n X radial or multiblock polymer. The polymer is generally recovered as a solid such as a crumb, powder or pellet. In the pJ-pB segment of the (pS-pI-pB) n X polymer, the polyisoprene is present in an amount sufficient to impart predominantly polyisoprene characteristics, not butadiene or polybutadiene characteristics, to the polymer. Thus, in the pI-pB segments of the polymer, the weight amount of polyisoprene will exceed 50% of the total weight of diene in the polymer, i.e., pI/(pI+pB)>50 wt %. Conversely, the weight amount of butadiene or polybutadiene will be less than 50% of the total weight of diene in the polymer, i.e., pB/(pI+pB)<50 wt %. Preferably, the polybutadiene portion of the diene segment is less than 10%, most preferably less than 5%, based on the total weight of the (pI+pB), or diene component of the polymer. The small amount of butadiene at the end of the diene midblock is useful in that it enhances the coupling reaction in formation of the radial polymer, and results in a radial polymer with a higher number of branches. The radial polymers of WO 95/14727 are thus synthesized by first contacting styrene with an initiator, suitably, for example, a sec-butyllithium initiator, in the presence of an inert diluent, for example, cyclohexane. A living polymer is then formed, as represented, for example, by the simplified structure pS-Li. The living polystyrene polymer pS-Li is next reacted with an isoprene monomer; the resulting product being represented by the simplified structure pS-pI-Li. The living polymer pS-pJ-Li is then reacted with a small amount of butadiene monomer to produce a living polymer with the structure pS-pI-pB-Li, pB represents butadiene or polybutadiene. Coupling of the pS-pJ-pB-Li with the coupling agent produces a branched block copolymer with the structure (pS-pI-pB) n X. The radial polymer that is produced, using SiCl 4 as a coupling agent, will render (pS-pI-pB) n X polymer where n is predominantly 4, i.e. more than 50 wt % of the radial copolymer is four-arm. The butadiene need be added only in an amount necessary to assure that the ends of all of the pI segments of the polymer chains are provided with at least one molecule of butadiene, though as suggested the butadiene can be added in larger or smaller amounts. Coupling agents which may be used to produce the radial polymers of WO95/14727 include those possessing four sites reactive toward carbon-lithium bonds. Suitable coupling agents are those compositions of the formula X(L) n where X represents the coupling moiety residue, and L is suitable leaving group. Exemplary of coupling agents of this type are silicon halides, for example, SiCl 4 , or a silane compound where one or more of the halides is substituted by an alkoxy group, for example, tetramethoxysilane or tetraethoxysilane compounds, epoxy compounds, for example, epoxidised linseed oil, epoxidised soybean oil; acrylate multi esters, for example, pentaerythritol tetraacrylate; epoxy silanes, divinyl compounds, for example, divinyl benzene, and the like. In addition to polystyrene, other alkenyl aromatic hydrocarbon monomers, such as alkyl-substituted styrenes, alkoxy-substituted styrenes, 2-vinyl pyridine, 4-vinyl pyridine, vinyl naphthalene, alkyl-substituted vinyl naphthalenes and the like. For simplicity herein, the terms styrene, styrenic, polystyrene content- and polystyrene equivalent molecular weight as used in this application are intended to include these other alkenyl aromatic hydrocarbons. The isoprene polymerization technique is preferably such that the stereochemistry of the polymerisable monomer is adjusted so that predominantly cis-1,4-polyisoprene having a glass transition temperature of less than −50° C. as measured by differential scanning calorimetry at a 10° C. per minute temperature scan rate is produced. The radial block copolymers are preferably produced by solution anionic techniques, although they could be prepared using bulk, solution or emulsion techniques. Such techniques entail contacting the monomers to be polymerized simultaneously or sequentially with an organoalkali metal compound in a suitable solvent at a temperature within the range from about −100° C. to about 150° C., preferably at a temperature within the range from about 0° C. to about 100° C. Particularly effective anionic polymerization initiators are organolithium compounds having the general formula: RLi n wherein: R is an aliphatic, cycloaliphatic, aromatic or alkyl-substituted aromatic hydrocarbon radical having from 1 to about 20 carbon atoms; and n is an integer of 1 to 3. In general, any of the solvents known to be useful in the preparation of such polymers may be used. Suitable solvents include straight- and branched chain hydrocarbons such as pentane, hexane, heptane, octane and the like, as well as alkyl-substituted derivatives thereof, cycloaliphatic hydrocarbons such as cyclopentane, cyclohexane, cycloheptane and the like, as well as alkyl-substituted derivatives thereof, aromatic and alkyl-substituted aromatic hydrocarbons such as benzene, toluene, xylene and the like; hydrogenated aromatic hydrocarbons, such as tetralin, decalin and the like. Linear and cyclic ethers such as dimethyl ether, methyl ethyl ether, anisole, tetrahydrofuran and the like may be used in small amounts. During the coupling reaction involved in producing radial block copolymers not all the polymer will be coupled. The coupling efficiency of radial block copolymers is defined as the mass of coupled polymer divided by the mass of coupled polymer plus the mass of uncoupled polymer. The coupling efficiency herein refers to that of the original polymer not including any degradation fragments formed during processing. Thus, when producing the (pS-pI-pB) n X branched polymers, the coupling efficiency is shown as a percentage by the following relationship: mass ⁢ ⁢ of ⁢ ⁢ coupled ⁢ ⁢ polymer mass ⁢ ⁢ of ⁢ ⁢ ( uncoupled + coupled ) ⁢ ⁢ polymer × 100 ⁢ ⁢ ( % ) Coupling efficiency can be measured by an analytical method such as gel permeation chromatography. Coupling efficiency can be controlled by a number of methods. One method to reduce coupling efficiency is to add less than the stoichiometric amount of coupling agent required for complete coupling of the polymers. Another means of reducing coupling efficiency is by the premature addition of a terminator compound. These terminators, such as water or alcohol, react very quickly and can easily be employed to cut short complete coupling of the polymers. In addition, by performing the coupling reaction at elevated temperatures, such as above about 90° C., thermal termination of many of the living polymer groups (pS-pI-Li) occurs prior to coupling. The typical coupling conditions include a temperature of between about 65° C. to about 75° C. and sufficient pressure to maintain the reactants in a liquid phase. Following the coupling reaction or when the desired coupling efficiency has been obtained, any remaining uncoupled product is terminated such as by the addition of terminators, for example, water, alcohol or other reagents, for the purpose of removing the lithium radical forming the nucleus for the condensed polymer product. The product is then recovered such as by coagulation utilizing hot water or steam or both, or alternatively by the use of a devolatilizing extruder. Radial four arms block copolymers and their use in hot melt adhesives are also described in European Patent Application 1103577 A1 and U.S. Pat. No. 5,292,819. The three and four arms products of these patents and the commercially available materials suffer from the disadvantages that they do not have optimum theological properties for use in permanent label adhesives. We have found that they have a coupling efficiency greater than 60%, generally greater than 70% and accordingly contain less than 40 wt % of diblock copolymer. These polymers tend to have too high a tensile strength and are harder and too cohesive to be useful in adhesive formulations and in other applications such as sound deadening, shock absorption and polymer modification. We have now developed radial block copolymer compositions which overcome these problems. We have found that, unlike the known products, if the diblock copolymer content of a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer is above 40 wt % of the total block copolymer content, an adhesive system having improved theological and improved die-cutting performance with desirable adhesive properties may be obtained. Some or all of the diblock may be produced during the manufacture of the radial copolymer. Surprisingly, we found that die-cutting takes place at relatively low deformation rates and involves pushing the adhesive to the side of the line of cut rather than involving a sharp cutting action. In successful die-cutting, the adhesive must creep when subjected to cutting knife action, flow away from the cut point, and not reform over the cut line. The creep of the adhesive may be illustrated by assuming typical conditions of die-cutting operations, i.e. a machine line speed of 100 m/min, a rotating cylinder of 10 cm diameter, and face paper and adhesive layers with a thickness of 80 and 20 microns, respectively. Since the diameter of the rotating cylinder is much larger (by a factor 100) than the overall thickness to indent, the effective vertical motion is only 10 cm/s when the knife starts to indent the face paper, and only 2 cm/s when the adhesive itself is indented. The second aspect has been discovered with the help of finite-element simulations of the die-cutting process performed with Abacus Software. These showed that the adhesive is pushed away by the much stiffer face paper, well before the cutting knife starts to indent the adhesive layer. In other words, the adhesive layer flows under the pressure imparted by the cutting knife on the face stock, which covers the adhesive layer. In most instances, no direct contact between the knife and the adhesive layer occurs. FIG. 2 , is an illustration of a die-cut label during the die cutting process, in which 1 is the release paper, 2 the adhesive layer, 3 is the frontal paper and 4 is the die-cutting blade which is moving in an anticlockwise direction to make the cut. The simulation illustration shows how as the knife crushes and breaks through the paper, the adhesive layer is pushed away under the paper from the line of cut, but that the knife itself does not cut through the adhesive layer. Accordingly, the more readily the adhesives flow and the less elastic they are, the easier and cleaner the cut will be. Altogether, both the surprisingly low deformations rates involved in the die-cutting process, as well as the need for the adhesive layer to undergo permanent flow during die-cutting operations explains why water-based acrylic adhesives behave better than their triblock (for example, SBS or SIS) counterparts. These two systems provide good examples of good and bad die-cutting behavior respectively. Viscoelastic behavior of hot-melt adhesives at a given temperature is conveniently captured by the two dynamic moduli known as G′ and G″, the loss modulus G″ giving an indication of the viscous behavior, and the storage modulus G′ giving an indication of the elastic behavior. The ratio of G″ and G′ is known as the loss factor Tangent delta (Tan δ). The finding that the cutting mechanism pushes the adhesive away from the line of cut rather than performing a sharp cut, leads to the conclusion that the adhesive should be less elastic to enable it to permanently flow away from the line of cut at the cutting temperature, normally room temperature. Emphasis should be put on the low frequency behavior because of the surprisingly small values for the vertical velocity of the knife during die-cutting operations. Dynamic mechanical analysis of acrylics systems shows indeed that the storage modulus G′ continuously decreases with frequency, with no indication of a constant plateau at low frequencies. At the same time, there is a relatively high loss modulus G″ at low frequency, essentially overlaying with G′. This amplifies the tendency of the adhesive to undergo permanent deformation and flow under stress, as shown in FIG. 3 . On the other hand, similar analysis of previous pure triblock copolymer based adhesives shows a constant and relatively high plateau modulus G′ (>10,000 Pa) in the low frequency region, much higher than the loss modulus G″, reflecting the tendency for the adhesive to recover from deformation, which is undesirable for die-cutting. We have found that there is also a marginal difference at high frequency, between the behavior of acrylics and the systems of the present invention (glass transition region and glassy domain), especially in the glass transition location on the frequency axis. The theological behavior at these frequencies can be modified by changing the tackifier package, which is known to minimally influence die-cutting behavior. Accordingly, we have found that, to have good die-cutting performance, an adhesive based on radial copolymers should fulfill the following criteria: G′ at room temperature should decrease monotonically with frequency, at frequencies below the glass transition region (typically <10 rad/s), down to a constant storage modulus plateau at the lowest frequencies. The elastic modulus plateau should be lower than 8,000 Pa, preferably lower than 6,000 Pa, more preferably lower than 5,000 Pa, most preferably lower than 4,000 Pa, when measured at 20° C. G′ should intersect a value of 10,000 Pa at a frequency that is preferably higher than 0.001 rad/s; preferably higher than 0.01 rad/s more preferably higher than 0.05 rad/s; most preferably higher than 0.1 rad/s, when measured at 20° C. The loss factor Tan δ defined as the ratio G″/G′ preferably comprises between 0.2 and 1.3, more preferably between 0.2 and 1.0, more preferably 0.3 to 1.0, more preferably 0.4 to 1.0, most preferably 0.6 to 1.0, at the frequency at which the storage modulus intersects a value of 10,000 Pa, when measured at 20° C. We have found that, in addition to the improved adhesion performances, desirable die-cuttability properties may be achieved using an adhesive system containing a styrenic block copolymer which contains a radial block copolymer and at least 40 wt % of a diblock styrenic copolymer. BRIEF SUMMARY OF THE INVENTION The present invention therefore provides a radial block copolymer composition and a pressure-sensitive adhesive composition based thereon. The pressure-sensitive adhesive was found to exhibit excellent adhesive properties and convertibility. The adhesive provides the ability to achieve clean rupture of the adhesive layer in processing operations involving cutting through a face stock to the release liner of the laminate. At the same time the adhesive provides excellent adhesive properties at both ambient and reduced temperatures, in particular the adhesive has high shear performance thus increasing flexibility in formulation. The adhesive is particularly suitable for use in labels on both paper and synthetic substrates. The adhesive also has low melt viscosity and may be applied as a hot melt, at low temperature. Accordingly the present invention provides a mixture of radial styrenic block copolymer and styrenic diblock copolymer comprising from 60 wt % to 10 wt % of radial styrenic block copolymer and from 40 wt % to 90 wt % of styrenic diblock copolymer. In a preferred mixture the radial styrenic block copolymer consists of i) a polystyrene block segment and ii) a polyisoprene block segment having an end which comprises butadiene, wherein the block copolymer is characterised by the formula: (pS-pI-pB) n X pS being polystyrene, pJ being polyisoprene, pB being polybutadiene, X being the residue of a multifunctional coupling agent used in the production of the radial block copolymer and n being a number greater than or equal to 3 and representing the average number of branches appended to X, and further wherein the pS component is present in an amount of at least 10 parts to about 35 parts per 100 parts by weight of the radial block copolymer; and the weight amount of polybutadiene in the pI-pB segment being less than 50 wt %. We prefer that n is predominantly 4. We further prefer that the weight amount of polybutadiene in the pI-pB segment is less than 10 wt %. The present invention further provides an adhesive system comprising a tackifier and a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer comprising from 60 wt % to 10 wt % of the radial styrenic block copolymer and from 40 wt % to 90 wt % of the styrenic diblock copolymer. The invention further provides the use in an adhesive of a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer comprising from 60 wt % to 10 wt % of the radial styrenic block copolymer and from 40 wt % to 90 wt % of the styrenic diblock copolymer. In a preferred embodiment the radial block copolymer is predominantly a four-arms radial block copolymer, is made by the process described in WO 95/14727 and has the properties described above in relation to the polymers of WO 95/14727. The process used to manufacture the four arms copolymers, as described above, generally results in the production of a small amount, typically no more than 10 wt %, of a three-arms radial copolymer. In another preferred embodiment the radial block copolymer has a molecular weight (Mw) above 200,000 g/mole preferably above 240,000 g/mole. It is further preferred that the molecular weight be no greater than 500,000 g/mole, more preferably no greater than 400,000 g/mole. It is yet further preferred that the radial block copolymer be a four-arm copolymer of molecular weight from 240,000 g/mole to 500,000 g/mole, preferably to 400,000 g/mole, more preferably to 375,000 g/mole. The use of the adhesive systems of the present invention has been found to enable improved die-cuttability in the production of labels. The invention therefore further provides the use of a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer comprising 60 wt % to 10 wt % of the radial styrenic block copolymer and 40 wt % to 90 wt % of the styrenic diblock copolymer in label adhesives. Furthermore, we have found that the use of these copolymer mixtures provide adhesives with lower melt viscosity and higher shear resistance. The invention further provides an adhesive composition providing improved die-cuttability performance when used as a hot melt label adhesive of a mixture of a tackifier and a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer comprising 60 wt % to 10 wt % of the radial styrenic copolymer rubber and containing 40 wt % to 90 wt % of the styrenic diblock copolymer. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a typical die-cutting process. FIG. 2 shows a simulation of the die-cutting. FIG. 3 compares G′ of comparative Example 1, a standard hot melt pressure sensitive based on pure triblock copolymer and an acrylic based adhesive. FIG. 4 shows the dynamic rheological properties, where they are compared with those of Comparative Example 1. FIG. 5 shows the die-cutting performance of the adhesive of Example 4 as tested on a printing die cutting machine, and as compared with a commercial Hot Melt Pressure Sensitive formulation based on linear block copolymers having an overall diblock content of 75% and with an acrylic based adhesive. DETAILED DESCRIPTION OF THE INVENTION The radial copolymers of the present invention are preferably composed of polystyrenic block segments, polydiene block segments, suitably polyisoprene block, or a predominantly polyisoprene block containing a relatively small amount of polybutadiene. Four arms radial copolymers are preferred. The radial styrenic copolymers may be prepared by any suitable polymerisation technique such as living anionic polymerization. Such polymer synthesis is described in U.S. Pat. Nos. 5,292,819 and 5,399,627. Radial copolymers being the result of a coupling mechanism between two “living” prepolymers, do contain varying amount of diblocks. As a result such diblock molecular weight is identical to the molecular weight of each radial arm. The block copolymer compositions of the present invention may be produced by controlling the coupling efficiency of the coupling reaction so that at least 40 wt % of the diblock material remains uncoupled, that is to say a coupling efficiency of less than 60%. This may be achieved by using the manufacturing techniques described in WO 95/14727 as for example by reducing the amount of coupling agent that is used. Alternatively the block copolymer compositions may be obtained by blending additional diblock material into the radial block copolymer (which may already contain some unreacted diblock material) to obtain a mixture containing the desired level of diblock material. In the adhesives of the present invention the radial copolymer diblock copolymer mixture is preferably used as the only copolymer in the adhesive system. Alternatively however they may be mixed with other polymers, particularly other styrenic block copolymers such as diblock and triblock copolymers or mixtures thereof. The block copolymers of the invention are preferably of styrene and isoprene. In order to get good die-cutting performance, the vinyl aromatic hydrocarbon content (generally styrene) of both the radial block copolymer and the diblock copolymer should be at least 10, preferably at least 11, more preferably at least 12, more preferably at least 13, more preferably at least 14, and more preferably at least 15% by weight. Similarly, the vinyl aromatic hydrocarbon content should be at or below 35, preferably at or below 34, preferably at or below 33, preferably at or below 32, preferably at or below 31, preferably at or below 30, preferably at or below 29, preferably at or below 28, preferably at or below 27, preferably at or below 26, preferably at or below 25, preferably at or below 24, preferably at or below 23, more preferably at or below 22, preferably at or below 21, preferably at or below 20, most preferably at or below 19% by weight. Preferred ranges for the vinyl aromatic hydrocarbon content may combine any upper and any lower limit described herein. Using polymers with this vinyl aromatic content results in a good combination of theological, die-cutting and adhesive performance. Lower levels of vinyl aromatics results in weak polymers, which impart poor shear properties, and higher levels give stiff adhesives, which are not sufficiently pressure sensitive. Accordingly, the invention provides rubbers having the combination of structure and rheology that, inter alia, achieves a combination of good die-cutting and adhesive properties in systems which use pressure sensitive adhesives. The adhesives are preferably applied as hot melts. The preferred rubbers of the present invention have the following properties: i) an overall minimum styrene content greater than 10, preferably 12, most preferably 15 wt %; ii) an overall maximum styrene content of 35, preferably 27, more preferably 22 wt %; iii) a maximum “pure” radial copolymer content of at most 60 wt %, preferably at most 55%, more preferably at most 50%, more preferably at most 45%, more preferably at most 40%, more preferably at most 35%, most preferably at most 30% based on the total amount of block copolymer present; and iv) a minimum diblock copolymer content of at least 40 wt %, preferably at least 45 wt %, preferably at least 50 wt %, preferably at least 55 wt %, more preferably at least 60 wt %, most preferably at least 70 wt % based on the total amount of block copolymer present. The radial copolymers of the present invention are preferably styrenic four arms. Where the rubber contains block polymers in addition to those produced during the manufacture of the radial block copolymers, these are preferably styrene/isoprene block polymers, and it is preferred that the molecular weight of any added triblock material, particularly a SIS triblock material, is at least 50,000 g/mole, more preferably at least 100,000 g/mole, and at most 300,000 g/mole, particularly preferred is 150,000 to 200,000 g/mole. It is preferred that the molecular weight of any added diblock material, be at least 50,000 g/mole preferably at least 60,000 g/mole, more preferably 70,000 g/mole, most preferably at least 80,000 g/mole and at most 150,000 g/mole, preferably 140,000 g/mole, most preferably 110,000 g/mole. Where the styrene diblock material is a styrene-butadiene material, it is preferred that it has a molecular weight from 50,000 to 150,000 g/mole, preferably 65,000 to 130,000 g/mole, such as 65,000 to 110,000, most preferably 70,000 to 90,000 g/mole. In every embodiment the total diblock content must exceed 40 wt %. Preferred ranges for the molecular weights in this paragraph may combine any upper and any lower limited set out above. For purposes of this specification, molecular weight means peak molecular weight as measured by Gel Permeation Chromatography (sometimes known as size exclusion chromatography) on a polystyrene calibration basis. Commercially available polystyrene standards were used for calibration and the molecular weights of copolymers were corrected according to Runyon et al, J. Applied Polymer Science , Vol. 13 Page 359 (1969) and Tung, L H J. Applied Polymer Science , Vol. 24 Page 953 (1979). In the case of the preferred mixture of four arms radial copolymers and diblock copolymers, the molecular weight of the pure radial copolymers were calculated as 4 times the measured molecular weight of the diblock molecular weight i.e. calculated as four times the molecular weight of the diblock copolymer obtained during the polymerization reaction. The molecular weights of the radial copolymers quoted in this application therefore refer to the molecular weight of the pure radial copolymer. A Hewlett-Packard Model 1090 chromatograph with a 1047A refractive index detector was used. The chromatograph was equipped with four 300 mm×7.5 mm Polymer Laboratories SEC columns packed with five micron particles. These consisted of two columns with 10 5 angstrom pore size, one column with 10 4 angstrom pore size, and one with mixed pore sizes. The carrier solvent was HPLC grade tetrahydrofuran (THF) with a flow of 1 ml/min. Column and detector temperatures were 40° C., and run time was 45 minutes. Tackifier additives for use in the adhesives of this invention are chosen according to the nature of the particular rubber that is used. Most tackifiers may be used. Preferred tackifiers are resins from aliphatic petroleum derivative streams containing 5- or -6-carbon-atom dienes and mono-olefins. The tackifiers range from materials that are normally liquid at room temperature to those that are normally solid at room temperature. The resins typically contain 40 wt % or more of polymerized dienes. The dienes are typically piperylene and/or isoprene. Useful tackifiers include Escorez 1310 LC and Escorez 2520 manufactured by ExxonMobil Chemical, Piccotac 95 manufactured by Eastman Chemical, and the Wingtack resin family manufactured by Goodyear (with the numerical designation being the softening point) such as Wingtack 95, which is a solid resin having a softening point of about 95° C., and Wingtack 10, which is a liquid resin having a softening point of about 10° C. Other suitable tackifiers include resins such as aliphatic/aromatic resins, which may or may not be hydrogenated such as the products ECR 373 having a softening point of about 90° C., or Escorez 2520 having a softening point of about 20° C. manufactured by ExxonMobil Chemical. Hydrogenated polycyclic resins (typically dicyclopentadiene resins such as Escorez 5300, 5320, 5340 and 5380 manufactured by ExxonMobil Chemical) and the like may also be used. Hydrogenated polycyclic aromatic modified resins, such as Escorez 5690, 5600 and 5620, manufactured by ExxonMobil Chemical, may also be used. Hydrogenated aromatic resins wherein a very substantial portion, if not all, of the benzene rings are converted to cyclohexane rings (for example, the Regalrez family of resins manufactured by Eastman Chemical such as Regalrez 1018, 1033, 1065, 1078 and 1126 and Regalite R-100, and the Arkon family of resins from Arakawa Chemical such as Arkon P-85, P-100, P-115 and P-125) may also be used. Rosin, rosin esters, polyterpenes, and other tackifiers, which are compatible with the polyisoprene and polybutadiene phases and to some degree with the polystyrene end blocks, can also be added. All such tackifiers may be used in hydrogenated or unhydrogenated form. Other additives include plasticizing oils such as Shellflex 371, manufactured by Shell, Kaydol mineral oil, manufactured by Witco and Flexon 876 manufactured by ExxonMobil, which are soluble in both the polyisoprene and polybutadiene phases combine any upper and any lower limit. Typically the adhesives may contain from 5 to 20 wt %, preferably from 5 to 15 wt %, more preferably from 10 to 15 wt % of the plasticizing oil. Preferred ranges for the amount of plasticizing oil in this paragraph are set out above. Preferred ranges for the quantities set out in this paragraph may combine any upper and any lower limits set out above. The tackifier may be present from 50% by weight, preferably from 55%, more preferably from 60%, based on the total weight of tackifier and copolymers. It may be present at up to 80% by weight, preferably up to 75%, more preferably up to 70% by weight. Conversely, the block copolymers are present from 20%, preferably from 25%, more preferably from 30%, by weight based on the weight of the tackifier and the copolymers and up to 50%, preferably up to 45%, by weight based on the combined weight of the tackifier system and the copolymers. The resin additives are preferably a mixture of a normally solid tackifier such as Escorez 1310 LC and a normally liquid tackifier such as Wingtack 10 or Escorez 2520. Preferred ranges for the quantities set out in this paragraph may combine any upper and any lower limits set out above. Petroleum resins are well known and are generally produced by Friedel-Crafts or thermal polymerization of various feeds, which may be pure monomer feeds or refinery streams containing mixtures of various unsaturated materials. Generally speaking, the purer the feed the easier to polymerize. For example, pure styrene, pure α-methyl styrene and mixtures thereof are easier to polymerize than a C 8 /C 9 refinery stream. Similarly, pure or concentrated piperylene is easier to polymerize than C 4 to C 6 refinery streams. But these pure monomers are more expensive to produce than the refinery streams that are often byproducts of large volume refining. Aliphatic hydrocarbon resins can be prepared by cationic polymerization of a cracked petroleum feed containing C 4 , C 5 , and C 6 paraffins, olefins, and diolefins also referred to as “C 5 monomers”. These monomer streams are comprised of cationically polymerisable monomers such as butadiene, 1,3-pentadiene (piperylene) along with cyclopentene, pentene, 2-methyl-2-butene, 2-methyl-2-pentene, isoprene, cyclopentadiene, and dicyclopentadiene. The refining streams are purified usually by both fractionation and impurity removal to obtain these feeds. Polymerizations are catalyzed using Friedel-Crafts catalysts such as unsupported Lewis acids (for example, boron trifluoride (BF 3 ), complexes of boron trifluoride, aluminum trichloride (AICI 3 ), or alkyl-aluminum halides, particularly chloride). In addition to the reactive components, non-polymerisable components in the feed include saturated hydrocarbons, which can be co-distilled with the unsaturated components such as pentane, cyclopentane, or 2-methylpentane. This monomer feed can be co-polymerized with other C 4 or C 5 olefins or dimers. The feed should be purified (typically by fractionation) to remove unsaturated materials that adversely affect the polymerization reaction or cause undesirable color of the final resin (for example, isoprene). Generally, C 5 aliphatic hydrocarbon resins are synthesized using a piperylene concentrate stream that is fractionation-enriched to increase the piperylene content and to reduce the difficult-to-polymerize, olefin and diolefin content. Typically, the feed stream includes at least 20 wt %, preferably 30 wt %, more preferably 50 wt %, monomer and up to 80 wt %, preferably 70 wt %, more preferably 30 wt %, solvent. The solvent may be an aromatic solvent, such as toluene, xylenes, and aromatic petroleum solvents, or their mixtures. The solvent may include an aliphatic solvent. Mixtures of aromatic and aliphatic solvents may also be used. The solvent may also be recycled. The solvent may be a non-polymerisable feed component. The feedstream may include at least C 4 to C 6 monomers, in which cyclopentadiene and methylcyclopentadiene components may be removed from the feed stream by heating at a temperature between 100° C. and 160° C. and fractionally distilling. The monomers may include at least one of isobutylene, butadiene, 2-methyl-2-butene, 1-pentene, 2-methyl-1-pentene, 2-methyl-2-pentene, 2-pentene, cyclopentene, isoprene, cyclohexene, 1,3-pentadiene, 1,4-pentadiene, isoprene, 1,3-hexadiene, 1,4-hexadiene, cyclopentadiene, and dicyclopentadiene. In accordance with another aspect, the feed stream can include at least 30 wt %, preferably 50 wt %, of C 5 monomers, as described above and at least 5 wt %, preferably 15 wt % of a co-feed including at least one of pure monomer, C 9 monomers, and terpenes. Likewise, the feed stream can include up to 95 wt %, preferably 85 wt % of C 5 monomers, as described above and 70 wt %, preferably 50 wt %, of a co-feed including at least one of pure monomer, C 9 monomers, and terpenes. The feed may also contain an aromatic olefin. Preferred aromatic olefins are those such as styrene, indene, and their derivatives. Particularly preferred aromatic olefins include styrene, α-methylstyrene, β-methylstyrene, indene, substituted indenes, such as methylindenes, and vinyl toluenes. The aromatic olefins are typically present at levels of at least 1 wt %, and at up to 50 wt %, more preferably 30 wt %, even more preferably 10 wt %. Polymerizations may be continuous or batch processes. A batch process reaction time is usually at least 30 minutes, preferably 60 minutes, and no greater than 8 hours, preferably 4 hours at a reaction temperature. Polymerization temperatures range from −50° C. to 150° C., preferably −20° C. to 100° C. Temperature significantly affects resin properties. Higher-molecular-weight and high-softening-point resins are prepared at lower reaction temperatures. Polymerization may be stopped by removing the catalyst from the hydrocarbon resin, for example, by filtration. The hydrocarbon resin may be removed from a fixed bed reactor, which includes the catalyst. The hydrocarbon resin may be stripped to remove unreacted monomers, solvents, and low-molecular-weight oligomers. The unreacted monomers, solvents, and low-molecular-weight oligomers may be recycled. The monomer feed can be co-polymerized with C 4 or C 5 olefin or dimers as chain transfer agents. Up to 40 wt % preferably up to 20 wt % of chain transfer agents may be added to obtain resins with lower molecular weight and narrower molecular weight distributions than can be prepared using the monomer feed alone. Chain transfer agents terminate polymer chain growth such that polymer initiation sites regenerate. Components that behave as chain transfer agents in these reactions include but are not limited to isobutylene, 2-methyl-1-butene, 2-methyl-2-butene, or dimers or oligomers of these species. The chain transfer agent can be added to the reaction in pure form or diluted in a solvent. Preferred solvents are aromatic solvents—typically toluene, xylenes, or light aromatic petroleum solvents. These solvents can be used fresh or recycled from the process. The solvents generally contain less than 200 ppm water, preferably less than 100 ppm water, and most preferably less than 50 ppm water. Typically, the resulting resin has a number average molecular weight (Mn) of at least 400, a weight average molecular weight (Mw) of at least 500, a Z average molecular weight (Mz) of at least 700, and a polydispersity (PD) as measured by Mw/Mn of at least 1.5 where Mn, Mw, and Mz are determined by Gel permeation chromatography. Similarly, the resin has a number average molecular weight (Mn) up to 2,000, a weight average molecular weight (Mw) of up to 3500, a Z average molecular weight (Mz) of up to 15,000 and a polydispersity (PD) as measured by Mw/Mn up to 4. Where hydrogenated resins are used, the hydrogenation may be carried out via molten resin or resin solution-based processes by either batch wise or, more commonly, continuous processes. Supported monometallic and bimetallic catalysts based on group-6, -8, -9, -10 or -11 elements are typically used for hydrocarbon resin hydrogenation. Catalysts such as supported nickel (for example, nickel on alumina, nickel on charcoal, nickel on silica, nickel on kieselguhr, etc), supported palladium (for example, palladium on silica, palladium on charcoal, palladium on magnesium oxide, etc) and supported copper and/or zinc (for example, copper chromite on copper and/or manganese oxide, copper and zinc on alumina, etc.) are good hydrogenation catalysts. The support material typically consists of porous inorganic refractory oxides such as silica, magnesia, silica-magnesia, zirconia, silica-zirconia, titania, silica-titania, alumina, silica-alumina, alumina-silicate, etc, with supports containing γ-alumina being highly preferred. Preferably, the supports are essentially free of crystalline molecular sieve materials. Mixtures of the foregoing oxides are also contemplated, especially homogeneous mixtures. Among the useful support materials in the present invention are the supports disclosed in the U.S. Pat. Nos. 4,686,030, 4,846,961, 4,500,424, and 4,849,093. Preferred supports include alumina, silica, carbon, MgO, TiO 2 , ZrO 2 , FeO 3 or their mixtures. Any of the known processes for catalytically hydrogenating hydrocarbon resins can be used; particularly the processes of U.S. Pat. Nos. 5,171,793, 4,629,766, 5,502,104 and 4,328,090 and WO 95/12623. Generic hydrogenation conditions include reaction temperatures of 100° C.-350° C. and hydrogen pressures of 5 atmospheres (506 kPa)-300 atmospheres (30390 kPa), for example, 10 to 275 atm (1013 kPa to 27579 kPa). A preferred hydrogenation temperature is in the range 180° C. to 320° C. and a preferred pressure is in the range 15195 kPa to 20260 kPa hydrogen. The hydrogen-to-feed volume ratio to the reactor under standard conditions (25° C., 1 atm (101 kPa) pressure) typically can range from 20-200. For water-white resins 100-200 is preferred. Another suitable process for resin hydrogenation is described in EP 0082726. EP 0082726 describes hydrogenation of a catalytic or thermal petroleum resin using nickel-tungsten catalyst on a γ-alumina support where the hydrogen pressure is 1.47×10 7 -1.96×10 7 Pa and the temperature ranges from 250-330° C. Thermal hydrogenation is usually performed at 160° C. to 320° C., at a pressure of 9.8×10 5 to 11.7×10 5 Pa and for a period typically of 1.5 to 4 hours. After hydrogenation, the reactor mixture may be flashed and further separated to recover the resin. Steam distillation may be used to eliminate oligomers, preferably without exceeding 325° C. In a particularly preferred embodiment, the catalyst comprises nickel and/or cobalt on one or more of molybdenum, tungsten, alumina or silica supports. In a preferred embodiment, the amount of nickel oxide and/or cobalt oxide on the support ranges from 2 to 10 wt %. The amount of tungsten or molybdenum oxide on the support after preparation ranges from 5 to 25 wt %. Preferably, the catalyst contains 4 to 7 wt % nickel oxide and 18 to 22 wt % tungsten oxide. This process and suitable catalysts are described in greater detail in U.S. Pat. No. 5,820,749. In another preferred embodiment, the hydrogenation may be carried out using the process and catalysts described in U.S. Pat. No. 4,629,766. In particular, nickel-tungsten catalysts on γ-alumina are preferred. While the pressure-sensitive adhesive formulations of the present invention exhibit excellent low temperature and ambient temperature performance as well as good die-cutting performance, they may also enhance elevated temperature performance. This may be accomplished by cross-linking techniques such as the use of electron beam (EB) radiation and ultraviolet (UV) radiation and chemical cross-linking. If employed, tackifying additives should be substantially saturated so that all of the energy of cure goes into cross-linking of the adhesives' elastomeric components. The adhesive formulations may also contain additives well known in the art such as anti-block, anti-static, antioxidants, UV stabilizers, neutralizers, lubricants, surfactants, anti-nucleating agents and/or fillers. Preferred additives include silica, titanium dioxide, polydimethylsiloxane, talc, dyes, wax, calcium stearate, calcium carbonate, carbon black, barium sulphate and magnesium silicate. The adhesives of the invention may be used as pressure sensitive adhesives, hot melt adhesives or contact adhesives and used in applications such as tapes, labels, paper impregnation, hot-melt adhesives, including woodworking, packaging, bookbinding or disposables, sealants, rubber compounds, pipe wrapping, carpet backing, contact adhesives, road-marking or tire construction. They are particularly useful as hot-melt pressure sensitive adhesives used for labels where they impart improved die-cutting performance, and also improved adhesive properties, particularly improved shear performance. In the Examples which follow, the block copolymers used in the adhesive formulations were prepared by the process described in WO 95/14727 and the desired ratio of radial and diblock copolymers was obtained by varying the amount of coupling agent and/or by blending. The procedures for the preparation of the hot melt adhesive blends, and of the coatings as well as the testing of the adhesive performances were as follow. The hot melt pressure sensitive adhesives were prepared by mixing the block copolymers with the tackifying resins in a laboratory z blade mixer of 300 ml capacity, at a temperature of about 145° C. A small amount of phenolic antioxidant was added to the blend to prevent its degradation during the blending process. The total mixing time was about 70 minutes. The tackifiers used were Escorez 1310 and ECR 373 from ExxonMobil Chemical and Wingtack 10 from Goodyear. Final blend viscosity was evaluated with a Brookfield viscosimeter according to a procedure based on ASTM D 3236-88. The pressure sensitive adhesives were applied as a hot melt to a silicone coated paper at a coating weight of about 20 grams/sq meter, using an Acumeter laboratory coater with a slot die for extrusion of the molten adhesive at a temperature of 165° C. The lamination was done according to industry practice, by transfer coating from the silicone coater paper release substrate to an 80 g/sq meter vellum paper frontal substrate. The adhesive performances were evaluated according to test methods published by FINAT, P.O. Box 85612 NL-2508 CH, The Hague, for example, FTM 1 for the peel adhesion at 180 degree FTM 9 for the loop tack measurements FTM 7 for the shear resistance Migration was evaluated by comparing the whiteness of the paper frontal substrate after ageing at 60° C. and 70° C. for one and two weeks. The whiteness was evaluated with a Hunterlab spectrophotometer. Dynamic theological properties at 20° C. were determined on RDAII and SR-500 instruments manufactured by Rheometric Scientific, Piscataway, N.J. The former gives access to frequencies between 10 −2 to 100 rad.s −1 and temperatures lower than 20° C. (down to −70° C.) to reach the glassy region obtained at higher frequencies. The SR-500 instrument, which covers a frequency range between 10 −5 to 100 rad.s −1 at room temperature, was used for the terminal zone (lower frequencies). We used plate-plate geometry for all experiments. The diameter of the plate decreases from 25 mm to 5 mm as temperature decreases in order to maintain the actual rheometer torque between measurable limits. Frequency sweeps were carried out at deformation levels well within the linear viscoelastic region. In order to broaden the range of accessible experimental frequencies, time-temperature superposition was applied with care. Measurements in the range of frequencies 10 −5 to 10 +2 were made at 20° C. To reach higher frequencies experiments at lower temperature were performed and the measurements extrapolated to 20° C. To ensure that experiments were conducted on bubble-free specimens, samples were degassed overnight under primary vacuum at about 90° C. Disks of adequate diameter were then compression molded, at a temperature systematically lower than the mixing temperature. EXAMPLES The following Examples A and B illustrate the Production of High Diblock/Radial Block copolymer Mixtures via control of coupling efficiency. Example A To a 5-gallon stirred reactor under a nitrogen atmosphere were added 12.5 kg of cyclohexane solvent and 84.0 g of a 0.17 M solution of sec-butyl lithium in cyclohexane. The temperature of the reactor was brought to 75° C. and 339 g of styrene was added. Polymerization of the styrene was allowed to continue for 36 minutes. The reaction mixture was cooled to 57° C. and 1692 g of isoprene was added. The isoprene was allowed to polymerize for 46 minutes, during which the reaction temperature reached a maximum of 92° C. At the end of the 46 minutes, 10 grams of butadiene was added at 71° C. and it was allowed to polymerize for an additional 34 minutes. Then 1.0 g of 0.87 M SiCl 4 in cyclohexane was added all at once. The reaction was allowed to continue for another 26 minutes before the reaction was terminated by addition of 3.0 ml of isopropanol. The resulting polymer was analyzed by GPC, and found to contain 82.0% diblock and 18.0% coupled radial block polymer. The radial block copolymer had 84% four arms, 16% three arms and no detectable two arms material. The styrene content was 16.6 wt % and the molecular weight of the diblock was 78,150. Example B To a 5-gallon stirred reactor under a nitrogen atmosphere were added 12.5 kg of cyclohexane solvent and 79.1 g of a 0.17 M solution of sec-butyl lithium in cyclohexane. The temperature of the reactor was brought to 82° C. and 339 g of styrene was added. Polymerization of the styrene was allowed to continue for 37 minutes. The reaction mixture was cooled to 58° C. and 1692 g of isoprene was added. The isoprene was allowed to polymerize for 26 minutes, during which the reaction temperature reached a maximum of 95° C. At the end of the 26 minutes, 10 grams of butadiene was added at 71° C. and it was allowed to polymerize for an additional 43 minutes. Then 3.1 g of 0.87 M SiCl 4 in cyclohexane was added all at once. The reaction was allowed to continue for another 31 minutes before the reaction was terminated by addition of 3.0 ml of isopropanol. The resulting polymer was analyzed by GPC, and found to contain 49.1% diblock, about 1% polystyrene homopolymer and the remainder coupled radial block polymer. The radial block copolymer had 78% four-arm and 15% three-arm, with the remainder two-arm materials. The styrene content was 16.6 wt % and the molecular weight of the diblock was 80,125. The following additional Examples illustrate adhesive systems according to the present invention. Styrene-isoprene four arms radial block copolymers having different contents of styrene-isoprene diblock copolymers and similar overall styrene content were used in a hot melt formulation containing 31 wt % total of block copolymer, 27 wt % of Wingtack 10, and 42 wt % of Escorez 1310 to which was added 0.4 wt % of Irganox 1076. The resulting hot melts show the following characteristics: Comparative Example 1 Example 2 Example 3 Example 4 Example 5 Radial polymer molecular 268000 290800 328000 332000 300000 weight Diblock molecular weight 67000 72700 82000 83000 75000 Styrene content (wt %) 20.5 17 18 17.8 17 Diblock content (wt %) 31 60 70 76 88 Brookfield Viscosity 6200 4960 5650 4460 1560 (175° C. - mPa · s) 180° peel strength - N/25 mm Room temperature - glass 29 cf 33.5 af 34.1 pt 36 29.5 cf 3° C. - glass 22 pt 18 pt 24 pt 22.6 pt Room temperature - PE 20.5 af 21 af 27 cf + pt 26 26 cf + pt 3° C. - PE 18.5 pt 18.5 pt 25 pt 21 pt Loop Tack - N glass at room temperature 23.5 af 22 af 28.3 af 37 38 cf glass at 3° C. 15 pt 6.5 af 15 pt 0.7 af 17 pt Loop Tack - N Polyethylene at room 18 af 14 af 21.2 af 24 af 24 af temperature Polyethylene at 3° C. 6.5 j 16.5 j + pt 5.0 j 18 pt Shear - room temperature - hours Steel - 25 × 25 mm - 1 kg >175 85-170 cf >150 cf 22-150 cf 3 cf Migration - % reflection 1 week  60° C. 90 88.5 86.9 89.5 87 2 weeks 60° C. 87 84 84.2 89 87.5 1 week  70° C. 82.5 85 83.8 82 80 2 weeks 70° C. 80 77 80.6 68 79 Rheology Frequency where G′ = 1000 1 10 −1 1.7 10 −1 1.1 10 −1 1.7 10 −1 3 10 −1 Pa (rad/s) * Tan delta at frequency 1.3 0.56 0.97 0.7 1.22 where G′ = 10,000 Pa * pt means paper tear cf means cohesive failure af means adhesive failure j means jerking * when measured at 20° C. FIG. 3 compares G′ of comparative Example 1, a standard hot melt pressure sensitive based on pure triblock copolymer and an acrylic based adhesive. The HMPSA adhesives of this invention have low viscosity, high shear properties for radials up to 80% diblock content, associated with excellent tack and peel performances at room and low temperature. The dynamic rheological properties are shown in FIG. 4 , where they are compared with those of Comparative Example 1. As it can be seen, the plateau modulus at low frequencies is decreasing when the level of diblock in the radial copolymer is increasing. The systems of the present invention have much lower moduli than the product of comparative Example 1. G′ intersects a value of 10000 Pa at frequencies higher than 10 −3 rad/s. At such frequencies Tan delta varies preferably from 0.35 to 1.22, preferably 0.56 to 1.22, when measured at 20° C. The die-cutting performance of the adhesive of Example 4 was tested on a printing die-cutting machine, and was compared with a commercial Hot Melt Pressure Sensitive formulation based on linear block copolymers having an overall diblock content of 75% and with an acrylic based adhesive. The tests were performed using different types of die shapes. The results are shown in FIG. 5 . The results shown in FIG. 5 , demonstrate that the reduced elastic behavior as shown in FIG. 4 (lower plateau modulus, higher loss factor Tan delta) provide to hot melt pressure sensitive adhesives based on radial copolymer with high diblock content significantly better die-cutting performance than commercially available copolymer based adhesive formulations and is close to the die-cutting behavior of acrylic based adhesives. We have also found that the radial block copolymer mixtures of the present invention have lower tensile strength and are softer and tackier than the previous mixtures with lower diblock content. This renders the polymers useful in applications such as sound deadening, shock absorption and polymer modification.
Improved adhesives are provided through the use of styrenic radial block copolymers, containing at least 40 wt % diblock copolymers, the adhesives have improved adhesive properties and a reduced elastic behavior under die-cutting conditions. Compared to conventional linear block copolymers of similar molecular weight, radial copolymers offer higher holding power and lower melt viscosity for the adhesive. They therefore contribute to an improved balance between processability and end-use properties.
Briefly summarize the main idea's components and working principles as described in the context.
[ "CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser.", "No. 10/490,973 filed Sep. 13, 2004.", "STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not applicable.", "THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT Not applicable.", "REFERENCE TO SEQUENCE LISTING Not applicable.", "FIELD OF THE INVENTION The present invention is directed to radial block copolymer compositions and pressure-sensitive adhesive compositions based thereon.", "The pressure-sensitive adhesives are particularly useful in label and tape manufacture.", "BACKGROUND OF THE INVENTION Radial block copolymers are known and it is also known that during their manufacture up to 20 wt % of the diblock copolymers remain unreacted and are present as diblock copolymer material.", "These low diblock content radial copolymers have been proposed as components in pressure-sensitive adhesives, where they are used to make during label manufacture, a laminate of a face stock, pressure-sensitive adhesive layer, and a release liner, such as silicone-coated paper, which is passed through an apparatus that converts the laminate into commercially useful labels and label stock.", "The converting operation processes involve printing, die-cutting, and matrix stripping to leave labels on a release liner, marginal hole punching, perforating, fan folding, guillotining and the like.", "It is important that the cutting action breaks the face stock and adhesive layer, but does not indent the release liner.", "Producing a series of labels on a backing sheet involves cutting around the label and removing the material between two labels (the matrix) while leaving the label itself attached to the backing sheet.", "It is important that the die-cutting machine make a clean break at operating speeds.", "The adhesive with the copolymer of low diblock content is formulated to have the desired viscoelastic and adhesive properties so that it can be applied to the release liner or the face-stock back, and will remain on the label after stripping and will have the required adhesion.", "But these are properties that make the adhesive film difficult to cut or break.", "These properties make die-cutting difficult and inconsistent, causing the adhesive lends to form adhesive strings and deposits on the cutting blade.", "FIG. 1 illustrates a typical die-cutting process.", "Die-cutting involves cutting the laminate through to the release liner face.", "Other procedures involve cutting completely through the label laminate and include hole punching, perforating, and guillotining, particularly on flat sheets.", "The cost of converting a laminate into a finished product, such as a label, is a function of the various processing operations'", "rates.", "Line speed depends on whether a printing step is involved.", "If there is no printing as with, for example, computer labels, speeds can reach 300 meters/minute.", "If label printing is involved, then speeds of 50-100 meters/minute are typical.", "While the nature of all laminate layers impact convertibility cost, the adhesive layer can limit convertibility ease.", "The adhesive layer's viscoelastic nature causes this limitation—in particular its high elasticity prevents it from flowing away from the cut line during die-cutting and also promotes its transfer to cutting blades during cutting.", "High adhesive elasticity also causes adhesive stringiness, which hinders matrix stripping as the unwanted facing material is removed after die-cutting.", "High elasticity also promotes adhesive layer reconnection after the layer is severed.", "Achieving good convertibility does not necessarily coincide with achieving excellent adhesive performance.", "Adhesives must be formulated to fit needs, and important properties include peel adhesion, tack, shear, and viscosity at various temperatures and adhesion on various substrates such as polymers, papers, glasses, and steels.", "Good, general-purpose adhesives may exhibit poor convertibility simply because the adhesive is difficult to cleanly sever.", "The adhesive may stick to a die or blade.", "As previously discussed in label manufacture, die-cutting and matrix stripping operations occur at speeds from 5-300 meters per minute, typically 50-100 meters per minute, if printing is involved.", "Within a range of speeds, use of a particular adhesive may result in breaking the matrix despite the fact that successful matrix stripping can occur at speeds on either side of the breaking speed.", "One goal is to provide adhesive systems where the adhesive has good die-cutting performance and where the matrix can be successfully stripped over the entire operating speed range.", "Typical label adhesives are produced from acrylic polymer emulsions, which may be tackified by hydrocarbon or natural-resin tackifiers.", "While these have good die-cutting performance, they require handling large volumes of liquid and subsequent liquid removal.", "Accordingly, adhesives applied as hot melts would be preferred.", "At low temperature, acrylic-based adhesives perform poorer than hot-melt systems.", "Moreover, hot melts can be used at faster line application speeds in a broader temperature range, have more aggressive tack, and can be used under humid conditions.", "It is however important that the adhesive has desired theological properties both for processability such as coating and at end use temperature.", "Hot-melt pressure-sensitive adhesive systems are well known and consist of tackified thermoplastic elastomers such as styrenic block copolymers together with tackifying resin(s) and generally some plasticizing oil, an antioxidant and optionally fillers.", "Styrenic block copolymers containing polystyrene and polybutadiene blocks and/or polyisoprene blocks are particularly useful.", "These materials are generally available as pure triblocks, (sometimes referred to as SIS and SBS copolymers), and diblocks (sometimes referred to as SI and SB copolymers).", "The materials are also available as mixtures of diblock and triblock materials (sometimes referred to as SIS+SI and SIS+SB).", "Examples of these materials are the Vector materials marketed by Dexco and the Kraton D materials marketed by Kraton Polymers.", "Radial block copolymers have also been proposed.", "It is known to use diblock/triblock blends as the elastomeric component in hot-melt pressure-sensitive adhesives.", "It is further known that adhesive properties and viscosity can be controlled by varying the diblock-to-triblock ratio, varying the styrene content, varying the polymer molecular weight, and varying the block molecular weights within the polymers.", "The melt viscosity can also be controlled by the addition of plasticizing oils and varying the molecular weight of the polymers.", "Examples of materials that have been used are Kraton D 1113, containing 16% styrene and 56% diblock;", "Quintac 3433, marketed by Nippon Zeon, containing 55% diblock and 17% styrene;", "Vector 4114, containing 42% diblock and 17% styrene;", "and Vector 4113 containing 20% diblock and 17% styrene.", "Vector 4114 and Vector 4113 are Dexco products.", "While these materials have good adhesive properties when tackified and can be used in hot melts for label production, they do not have optimum die-cutting properties.", "Furthermore, their balance of adhesive properties is not optimum.", "U.S. Pat. No. 5,663,228 concerns improving label adhesive die-cuttability.", "But the proposed solution is different and more complicated than the present invention and requires the use of two particular block copolymer resins having certain glass-transition temperatures and the choice of a tackifying resin that, when mixed with the two particular block copolymers, increases the difference between the two block copolymers'", "glass transition temperatures.", "U.S. Pat. No. 5,663,228 also does not appreciate the importance of the adhesive's elastomeric behavior under die-cutting conditions.", "Examples of styrenic copolymers that are used in the adhesive mixtures of U.S. Pat. No. 5,663,228 are Finaprene 1205 available from AtoFina and Kraton 1107 available from Kraton Polymers.", "U.S. Pat. No. 5,412,032 concerns linear SIS triblock/diblock copolymers that can be used in labels to improve die-cutting.", "This is accomplished using block copolymers with a styrene content from 18 to 24 wt %, a polystyrene block molecular weight from 25,000 to 35,000 an overall molecular weight of above 280,000 up to 520,000 and a coupling efficiency of 20% to 40%.", "The coupling efficiency corresponds to the percentage of triblock material in the overall block copolymer.", "PCT Patent applications PCT/US01/20671 and PCT/US01/20609 describe the use of certain diblock/triblock blends and the use of tetrablock and pentablock copolymers in label adhesives to improve die-cutting performance.", "It is also known to use radial block copolymers in hot melt adhesives.", "For example, U.S. Pat. Nos. 5,194,500 and 5,750,607 relate to styrene-isoprene three-arm block copolymers and their use in adhesives.", "These three-arm radial copolymers are available as Kraton 1124 from Kraton Polymers and Quintac 3450 and Quintac 3460C from Nippon Zeon.", "International Patent Publications WO 92/20725 and WO 95/14727 are concerned with radial block copolymers comprising polystyrene block segments and diene block segments, the diene block segment is preferably predominately polyisoprene block containing a small amount of butadiene at the end of the diene block to ensure multi arm coupling.", "These publications also disclose the use of these polymers in hot melt adhesive systems.", "WO 92/20725 is primarily concerned with the use of such polymers in adhesives used in disposable articles.", "WO 95/14727 is concerned with achieving optimum balance between high holding power and low melt viscosity of the adhesives.", "European Patent Application 0798358 A1 is concerned with hot melt adhesives, particularly hot melt adhesives for labeling which have a reduced viscosity.", "The adhesives have a low diblock content and we have found that this results in an adhesive that is too cohesive and has high elasticity which is detrimental for die cuttability as is shown in Comparative Example 1 which is based on the radial polymer DPX-551 mentioned in European Patent Application 0798358 A1 as a suitable polymer for use in its adhesive formulations.", "The radial block copolymers of WO 95/14727 are characterised by the formula: (pS-pI-pB) n X (1) wherein pS is polystyrene, pJ is polyisoprene, pB is polybutadiene, X is a residue of a multifunctional coupling agent used in the production of the radial block copolymer, and n is a number greater than or equal to 3 and representative of the number of branches appended to X. According to WO 95/14727 the number n is predominately 4.", "The molecular weight of the pS block of the radial block copolymer is between about 10,000 to about 15,000 g/mole, preferably from about 12,000 to about 14,000 g/mole.", "The pJ-pB block preferably has a total average number molecular weight (polystyrene equivalent molecular weight) ranging from about 40,000 to about 130,000 g/mole, preferably from about 50,000 to about 115,000 g/mole.", "The overall number average molecular weight (polystyrene equivalent) of the radial block copolymer ranges from about 200,000 to about 400,000 g/mole, preferably from about 225,000 to about 360,000 g/mole, and the polystyrene block pS component is present in an amount of at least about 14 to about 24 parts, preferably from about 15 to about 22 parts, per 100 parts by weight of the radial block copolymer.", "The radial block copolymers of WO 95/14727 are thus constituted of polystyrene block segments and polydiene block segments in accordance with formula (1).", "The copolymers may be random, tapered, block or a combination of these, provided that the polybutadiene segment acts as the terminus segment of the polydiene block so that it may react with the coupling agent.", "The other end block of the polymer is polystyrene.", "The pS segment is generally prepared by sequentially polymerizing styrene.", "In accordance with formula (1), isoprene is employed to make the pJ segments, the (pS-pJ) polymer chains being formed by sequential polymerization of isoprene with the pS.", "The pS-pJ-pB-Li polymer chains are then formed by the sequential polymerization of living pS-pI-Li polymer chains with butadiene.", "The radial or multiblock (pS-pI-pB) n X copolymers are correspondingly made by coupling the pS-pJ-pB-Li living polymer chains with a multi- or tetra-functional coupling agent, such as SiCl 4 .", "Thus, the styrene is polymerized to form pS, the isoprene is then introduced to form pS-pI, the butadiene is then introduced to form pS-pI-pB, and the pS-pJ-pB chains are then coupled with the tetrafunctional coupling agent to form the (pS-pI-pB) n X radial or multiblock polymer.", "The polymer is generally recovered as a solid such as a crumb, powder or pellet.", "In the pJ-pB segment of the (pS-pI-pB) n X polymer, the polyisoprene is present in an amount sufficient to impart predominantly polyisoprene characteristics, not butadiene or polybutadiene characteristics, to the polymer.", "Thus, in the pI-pB segments of the polymer, the weight amount of polyisoprene will exceed 50% of the total weight of diene in the polymer, i.e., pI/(pI+pB)>50 wt %.", "Conversely, the weight amount of butadiene or polybutadiene will be less than 50% of the total weight of diene in the polymer, i.e., pB/(pI+pB)<50 wt %.", "Preferably, the polybutadiene portion of the diene segment is less than 10%, most preferably less than 5%, based on the total weight of the (pI+pB), or diene component of the polymer.", "The small amount of butadiene at the end of the diene midblock is useful in that it enhances the coupling reaction in formation of the radial polymer, and results in a radial polymer with a higher number of branches.", "The radial polymers of WO 95/14727 are thus synthesized by first contacting styrene with an initiator, suitably, for example, a sec-butyllithium initiator, in the presence of an inert diluent, for example, cyclohexane.", "A living polymer is then formed, as represented, for example, by the simplified structure pS-Li.", "The living polystyrene polymer pS-Li is next reacted with an isoprene monomer;", "the resulting product being represented by the simplified structure pS-pI-Li.", "The living polymer pS-pJ-Li is then reacted with a small amount of butadiene monomer to produce a living polymer with the structure pS-pI-pB-Li, pB represents butadiene or polybutadiene.", "Coupling of the pS-pJ-pB-Li with the coupling agent produces a branched block copolymer with the structure (pS-pI-pB) n X. The radial polymer that is produced, using SiCl 4 as a coupling agent, will render (pS-pI-pB) n X polymer where n is predominantly 4, i.e. more than 50 wt % of the radial copolymer is four-arm.", "The butadiene need be added only in an amount necessary to assure that the ends of all of the pI segments of the polymer chains are provided with at least one molecule of butadiene, though as suggested the butadiene can be added in larger or smaller amounts.", "Coupling agents which may be used to produce the radial polymers of WO95/14727 include those possessing four sites reactive toward carbon-lithium bonds.", "Suitable coupling agents are those compositions of the formula X(L) n where X represents the coupling moiety residue, and L is suitable leaving group.", "Exemplary of coupling agents of this type are silicon halides, for example, SiCl 4 , or a silane compound where one or more of the halides is substituted by an alkoxy group, for example, tetramethoxysilane or tetraethoxysilane compounds, epoxy compounds, for example, epoxidised linseed oil, epoxidised soybean oil;", "acrylate multi esters, for example, pentaerythritol tetraacrylate;", "epoxy silanes, divinyl compounds, for example, divinyl benzene, and the like.", "In addition to polystyrene, other alkenyl aromatic hydrocarbon monomers, such as alkyl-substituted styrenes, alkoxy-substituted styrenes, 2-vinyl pyridine, 4-vinyl pyridine, vinyl naphthalene, alkyl-substituted vinyl naphthalenes and the like.", "For simplicity herein, the terms styrene, styrenic, polystyrene content- and polystyrene equivalent molecular weight as used in this application are intended to include these other alkenyl aromatic hydrocarbons.", "The isoprene polymerization technique is preferably such that the stereochemistry of the polymerisable monomer is adjusted so that predominantly cis-1,4-polyisoprene having a glass transition temperature of less than −50° C. as measured by differential scanning calorimetry at a 10° C. per minute temperature scan rate is produced.", "The radial block copolymers are preferably produced by solution anionic techniques, although they could be prepared using bulk, solution or emulsion techniques.", "Such techniques entail contacting the monomers to be polymerized simultaneously or sequentially with an organoalkali metal compound in a suitable solvent at a temperature within the range from about −100° C. to about 150° C., preferably at a temperature within the range from about 0° C. to about 100° C. Particularly effective anionic polymerization initiators are organolithium compounds having the general formula: RLi n wherein: R is an aliphatic, cycloaliphatic, aromatic or alkyl-substituted aromatic hydrocarbon radical having from 1 to about 20 carbon atoms;", "and n is an integer of 1 to 3.", "In general, any of the solvents known to be useful in the preparation of such polymers may be used.", "Suitable solvents include straight- and branched chain hydrocarbons such as pentane, hexane, heptane, octane and the like, as well as alkyl-substituted derivatives thereof, cycloaliphatic hydrocarbons such as cyclopentane, cyclohexane, cycloheptane and the like, as well as alkyl-substituted derivatives thereof, aromatic and alkyl-substituted aromatic hydrocarbons such as benzene, toluene, xylene and the like;", "hydrogenated aromatic hydrocarbons, such as tetralin, decalin and the like.", "Linear and cyclic ethers such as dimethyl ether, methyl ethyl ether, anisole, tetrahydrofuran and the like may be used in small amounts.", "During the coupling reaction involved in producing radial block copolymers not all the polymer will be coupled.", "The coupling efficiency of radial block copolymers is defined as the mass of coupled polymer divided by the mass of coupled polymer plus the mass of uncoupled polymer.", "The coupling efficiency herein refers to that of the original polymer not including any degradation fragments formed during processing.", "Thus, when producing the (pS-pI-pB) n X branched polymers, the coupling efficiency is shown as a percentage by the following relationship: mass ⁢ ⁢ of ⁢ ⁢ coupled ⁢ ⁢ polymer mass ⁢ ⁢ of ⁢ ⁢ ( uncoupled + coupled ) ⁢ ⁢ polymer × 100 ⁢ ⁢ ( % ) Coupling efficiency can be measured by an analytical method such as gel permeation chromatography.", "Coupling efficiency can be controlled by a number of methods.", "One method to reduce coupling efficiency is to add less than the stoichiometric amount of coupling agent required for complete coupling of the polymers.", "Another means of reducing coupling efficiency is by the premature addition of a terminator compound.", "These terminators, such as water or alcohol, react very quickly and can easily be employed to cut short complete coupling of the polymers.", "In addition, by performing the coupling reaction at elevated temperatures, such as above about 90° C., thermal termination of many of the living polymer groups (pS-pI-Li) occurs prior to coupling.", "The typical coupling conditions include a temperature of between about 65° C. to about 75° C. and sufficient pressure to maintain the reactants in a liquid phase.", "Following the coupling reaction or when the desired coupling efficiency has been obtained, any remaining uncoupled product is terminated such as by the addition of terminators, for example, water, alcohol or other reagents, for the purpose of removing the lithium radical forming the nucleus for the condensed polymer product.", "The product is then recovered such as by coagulation utilizing hot water or steam or both, or alternatively by the use of a devolatilizing extruder.", "Radial four arms block copolymers and their use in hot melt adhesives are also described in European Patent Application 1103577 A1 and U.S. Pat. No. 5,292,819.", "The three and four arms products of these patents and the commercially available materials suffer from the disadvantages that they do not have optimum theological properties for use in permanent label adhesives.", "We have found that they have a coupling efficiency greater than 60%, generally greater than 70% and accordingly contain less than 40 wt % of diblock copolymer.", "These polymers tend to have too high a tensile strength and are harder and too cohesive to be useful in adhesive formulations and in other applications such as sound deadening, shock absorption and polymer modification.", "We have now developed radial block copolymer compositions which overcome these problems.", "We have found that, unlike the known products, if the diblock copolymer content of a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer is above 40 wt % of the total block copolymer content, an adhesive system having improved theological and improved die-cutting performance with desirable adhesive properties may be obtained.", "Some or all of the diblock may be produced during the manufacture of the radial copolymer.", "Surprisingly, we found that die-cutting takes place at relatively low deformation rates and involves pushing the adhesive to the side of the line of cut rather than involving a sharp cutting action.", "In successful die-cutting, the adhesive must creep when subjected to cutting knife action, flow away from the cut point, and not reform over the cut line.", "The creep of the adhesive may be illustrated by assuming typical conditions of die-cutting operations, i.e. a machine line speed of 100 m/min, a rotating cylinder of 10 cm diameter, and face paper and adhesive layers with a thickness of 80 and 20 microns, respectively.", "Since the diameter of the rotating cylinder is much larger (by a factor 100) than the overall thickness to indent, the effective vertical motion is only 10 cm/s when the knife starts to indent the face paper, and only 2 cm/s when the adhesive itself is indented.", "The second aspect has been discovered with the help of finite-element simulations of the die-cutting process performed with Abacus Software.", "These showed that the adhesive is pushed away by the much stiffer face paper, well before the cutting knife starts to indent the adhesive layer.", "In other words, the adhesive layer flows under the pressure imparted by the cutting knife on the face stock, which covers the adhesive layer.", "In most instances, no direct contact between the knife and the adhesive layer occurs.", "FIG. 2 , is an illustration of a die-cut label during the die cutting process, in which 1 is the release paper, 2 the adhesive layer, 3 is the frontal paper and 4 is the die-cutting blade which is moving in an anticlockwise direction to make the cut.", "The simulation illustration shows how as the knife crushes and breaks through the paper, the adhesive layer is pushed away under the paper from the line of cut, but that the knife itself does not cut through the adhesive layer.", "Accordingly, the more readily the adhesives flow and the less elastic they are, the easier and cleaner the cut will be.", "Altogether, both the surprisingly low deformations rates involved in the die-cutting process, as well as the need for the adhesive layer to undergo permanent flow during die-cutting operations explains why water-based acrylic adhesives behave better than their triblock (for example, SBS or SIS) counterparts.", "These two systems provide good examples of good and bad die-cutting behavior respectively.", "Viscoelastic behavior of hot-melt adhesives at a given temperature is conveniently captured by the two dynamic moduli known as G′ and G″, the loss modulus G″ giving an indication of the viscous behavior, and the storage modulus G′ giving an indication of the elastic behavior.", "The ratio of G″ and G′ is known as the loss factor Tangent delta (Tan δ).", "The finding that the cutting mechanism pushes the adhesive away from the line of cut rather than performing a sharp cut, leads to the conclusion that the adhesive should be less elastic to enable it to permanently flow away from the line of cut at the cutting temperature, normally room temperature.", "Emphasis should be put on the low frequency behavior because of the surprisingly small values for the vertical velocity of the knife during die-cutting operations.", "Dynamic mechanical analysis of acrylics systems shows indeed that the storage modulus G′ continuously decreases with frequency, with no indication of a constant plateau at low frequencies.", "At the same time, there is a relatively high loss modulus G″ at low frequency, essentially overlaying with G′.", "This amplifies the tendency of the adhesive to undergo permanent deformation and flow under stress, as shown in FIG. 3 .", "On the other hand, similar analysis of previous pure triblock copolymer based adhesives shows a constant and relatively high plateau modulus G′ (>10,000 Pa) in the low frequency region, much higher than the loss modulus G″, reflecting the tendency for the adhesive to recover from deformation, which is undesirable for die-cutting.", "We have found that there is also a marginal difference at high frequency, between the behavior of acrylics and the systems of the present invention (glass transition region and glassy domain), especially in the glass transition location on the frequency axis.", "The theological behavior at these frequencies can be modified by changing the tackifier package, which is known to minimally influence die-cutting behavior.", "Accordingly, we have found that, to have good die-cutting performance, an adhesive based on radial copolymers should fulfill the following criteria: G′ at room temperature should decrease monotonically with frequency, at frequencies below the glass transition region (typically <10 rad/s), down to a constant storage modulus plateau at the lowest frequencies.", "The elastic modulus plateau should be lower than 8,000 Pa, preferably lower than 6,000 Pa, more preferably lower than 5,000 Pa, most preferably lower than 4,000 Pa, when measured at 20° C. G′ should intersect a value of 10,000 Pa at a frequency that is preferably higher than 0.001 rad/s;", "preferably higher than 0.01 rad/s more preferably higher than 0.05 rad/s;", "most preferably higher than 0.1 rad/s, when measured at 20° C. The loss factor Tan δ defined as the ratio G″/G′ preferably comprises between 0.2 and 1.3, more preferably between 0.2 and 1.0, more preferably 0.3 to 1.0, more preferably 0.4 to 1.0, most preferably 0.6 to 1.0, at the frequency at which the storage modulus intersects a value of 10,000 Pa, when measured at 20° C. We have found that, in addition to the improved adhesion performances, desirable die-cuttability properties may be achieved using an adhesive system containing a styrenic block copolymer which contains a radial block copolymer and at least 40 wt % of a diblock styrenic copolymer.", "BRIEF SUMMARY OF THE INVENTION The present invention therefore provides a radial block copolymer composition and a pressure-sensitive adhesive composition based thereon.", "The pressure-sensitive adhesive was found to exhibit excellent adhesive properties and convertibility.", "The adhesive provides the ability to achieve clean rupture of the adhesive layer in processing operations involving cutting through a face stock to the release liner of the laminate.", "At the same time the adhesive provides excellent adhesive properties at both ambient and reduced temperatures, in particular the adhesive has high shear performance thus increasing flexibility in formulation.", "The adhesive is particularly suitable for use in labels on both paper and synthetic substrates.", "The adhesive also has low melt viscosity and may be applied as a hot melt, at low temperature.", "Accordingly the present invention provides a mixture of radial styrenic block copolymer and styrenic diblock copolymer comprising from 60 wt % to 10 wt % of radial styrenic block copolymer and from 40 wt % to 90 wt % of styrenic diblock copolymer.", "In a preferred mixture the radial styrenic block copolymer consists of i) a polystyrene block segment and ii) a polyisoprene block segment having an end which comprises butadiene, wherein the block copolymer is characterised by the formula: (pS-pI-pB) n X pS being polystyrene, pJ being polyisoprene, pB being polybutadiene, X being the residue of a multifunctional coupling agent used in the production of the radial block copolymer and n being a number greater than or equal to 3 and representing the average number of branches appended to X, and further wherein the pS component is present in an amount of at least 10 parts to about 35 parts per 100 parts by weight of the radial block copolymer;", "and the weight amount of polybutadiene in the pI-pB segment being less than 50 wt %.", "We prefer that n is predominantly 4.", "We further prefer that the weight amount of polybutadiene in the pI-pB segment is less than 10 wt %.", "The present invention further provides an adhesive system comprising a tackifier and a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer comprising from 60 wt % to 10 wt % of the radial styrenic block copolymer and from 40 wt % to 90 wt % of the styrenic diblock copolymer.", "The invention further provides the use in an adhesive of a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer comprising from 60 wt % to 10 wt % of the radial styrenic block copolymer and from 40 wt % to 90 wt % of the styrenic diblock copolymer.", "In a preferred embodiment the radial block copolymer is predominantly a four-arms radial block copolymer, is made by the process described in WO 95/14727 and has the properties described above in relation to the polymers of WO 95/14727.", "The process used to manufacture the four arms copolymers, as described above, generally results in the production of a small amount, typically no more than 10 wt %, of a three-arms radial copolymer.", "In another preferred embodiment the radial block copolymer has a molecular weight (Mw) above 200,000 g/mole preferably above 240,000 g/mole.", "It is further preferred that the molecular weight be no greater than 500,000 g/mole, more preferably no greater than 400,000 g/mole.", "It is yet further preferred that the radial block copolymer be a four-arm copolymer of molecular weight from 240,000 g/mole to 500,000 g/mole, preferably to 400,000 g/mole, more preferably to 375,000 g/mole.", "The use of the adhesive systems of the present invention has been found to enable improved die-cuttability in the production of labels.", "The invention therefore further provides the use of a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer comprising 60 wt % to 10 wt % of the radial styrenic block copolymer and 40 wt % to 90 wt % of the styrenic diblock copolymer in label adhesives.", "Furthermore, we have found that the use of these copolymer mixtures provide adhesives with lower melt viscosity and higher shear resistance.", "The invention further provides an adhesive composition providing improved die-cuttability performance when used as a hot melt label adhesive of a mixture of a tackifier and a mixture of a radial styrenic block copolymer and a styrenic diblock copolymer comprising 60 wt % to 10 wt % of the radial styrenic copolymer rubber and containing 40 wt % to 90 wt % of the styrenic diblock copolymer.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a typical die-cutting process.", "FIG. 2 shows a simulation of the die-cutting.", "FIG. 3 compares G′ of comparative Example 1, a standard hot melt pressure sensitive based on pure triblock copolymer and an acrylic based adhesive.", "FIG. 4 shows the dynamic rheological properties, where they are compared with those of Comparative Example 1.", "FIG. 5 shows the die-cutting performance of the adhesive of Example 4 as tested on a printing die cutting machine, and as compared with a commercial Hot Melt Pressure Sensitive formulation based on linear block copolymers having an overall diblock content of 75% and with an acrylic based adhesive.", "DETAILED DESCRIPTION OF THE INVENTION The radial copolymers of the present invention are preferably composed of polystyrenic block segments, polydiene block segments, suitably polyisoprene block, or a predominantly polyisoprene block containing a relatively small amount of polybutadiene.", "Four arms radial copolymers are preferred.", "The radial styrenic copolymers may be prepared by any suitable polymerisation technique such as living anionic polymerization.", "Such polymer synthesis is described in U.S. Pat. Nos. 5,292,819 and 5,399,627.", "Radial copolymers being the result of a coupling mechanism between two “living”", "prepolymers, do contain varying amount of diblocks.", "As a result such diblock molecular weight is identical to the molecular weight of each radial arm.", "The block copolymer compositions of the present invention may be produced by controlling the coupling efficiency of the coupling reaction so that at least 40 wt % of the diblock material remains uncoupled, that is to say a coupling efficiency of less than 60%.", "This may be achieved by using the manufacturing techniques described in WO 95/14727 as for example by reducing the amount of coupling agent that is used.", "Alternatively the block copolymer compositions may be obtained by blending additional diblock material into the radial block copolymer (which may already contain some unreacted diblock material) to obtain a mixture containing the desired level of diblock material.", "In the adhesives of the present invention the radial copolymer diblock copolymer mixture is preferably used as the only copolymer in the adhesive system.", "Alternatively however they may be mixed with other polymers, particularly other styrenic block copolymers such as diblock and triblock copolymers or mixtures thereof.", "The block copolymers of the invention are preferably of styrene and isoprene.", "In order to get good die-cutting performance, the vinyl aromatic hydrocarbon content (generally styrene) of both the radial block copolymer and the diblock copolymer should be at least 10, preferably at least 11, more preferably at least 12, more preferably at least 13, more preferably at least 14, and more preferably at least 15% by weight.", "Similarly, the vinyl aromatic hydrocarbon content should be at or below 35, preferably at or below 34, preferably at or below 33, preferably at or below 32, preferably at or below 31, preferably at or below 30, preferably at or below 29, preferably at or below 28, preferably at or below 27, preferably at or below 26, preferably at or below 25, preferably at or below 24, preferably at or below 23, more preferably at or below 22, preferably at or below 21, preferably at or below 20, most preferably at or below 19% by weight.", "Preferred ranges for the vinyl aromatic hydrocarbon content may combine any upper and any lower limit described herein.", "Using polymers with this vinyl aromatic content results in a good combination of theological, die-cutting and adhesive performance.", "Lower levels of vinyl aromatics results in weak polymers, which impart poor shear properties, and higher levels give stiff adhesives, which are not sufficiently pressure sensitive.", "Accordingly, the invention provides rubbers having the combination of structure and rheology that, inter alia, achieves a combination of good die-cutting and adhesive properties in systems which use pressure sensitive adhesives.", "The adhesives are preferably applied as hot melts.", "The preferred rubbers of the present invention have the following properties: i) an overall minimum styrene content greater than 10, preferably 12, most preferably 15 wt %;", "ii) an overall maximum styrene content of 35, preferably 27, more preferably 22 wt %;", "iii) a maximum “pure”", "radial copolymer content of at most 60 wt %, preferably at most 55%, more preferably at most 50%, more preferably at most 45%, more preferably at most 40%, more preferably at most 35%, most preferably at most 30% based on the total amount of block copolymer present;", "and iv) a minimum diblock copolymer content of at least 40 wt %, preferably at least 45 wt %, preferably at least 50 wt %, preferably at least 55 wt %, more preferably at least 60 wt %, most preferably at least 70 wt % based on the total amount of block copolymer present.", "The radial copolymers of the present invention are preferably styrenic four arms.", "Where the rubber contains block polymers in addition to those produced during the manufacture of the radial block copolymers, these are preferably styrene/isoprene block polymers, and it is preferred that the molecular weight of any added triblock material, particularly a SIS triblock material, is at least 50,000 g/mole, more preferably at least 100,000 g/mole, and at most 300,000 g/mole, particularly preferred is 150,000 to 200,000 g/mole.", "It is preferred that the molecular weight of any added diblock material, be at least 50,000 g/mole preferably at least 60,000 g/mole, more preferably 70,000 g/mole, most preferably at least 80,000 g/mole and at most 150,000 g/mole, preferably 140,000 g/mole, most preferably 110,000 g/mole.", "Where the styrene diblock material is a styrene-butadiene material, it is preferred that it has a molecular weight from 50,000 to 150,000 g/mole, preferably 65,000 to 130,000 g/mole, such as 65,000 to 110,000, most preferably 70,000 to 90,000 g/mole.", "In every embodiment the total diblock content must exceed 40 wt %.", "Preferred ranges for the molecular weights in this paragraph may combine any upper and any lower limited set out above.", "For purposes of this specification, molecular weight means peak molecular weight as measured by Gel Permeation Chromatography (sometimes known as size exclusion chromatography) on a polystyrene calibration basis.", "Commercially available polystyrene standards were used for calibration and the molecular weights of copolymers were corrected according to Runyon et al, J. Applied Polymer Science , Vol. 13 Page 359 (1969) and Tung, L H J. Applied Polymer Science , Vol. 24 Page 953 (1979).", "In the case of the preferred mixture of four arms radial copolymers and diblock copolymers, the molecular weight of the pure radial copolymers were calculated as 4 times the measured molecular weight of the diblock molecular weight i.e. calculated as four times the molecular weight of the diblock copolymer obtained during the polymerization reaction.", "The molecular weights of the radial copolymers quoted in this application therefore refer to the molecular weight of the pure radial copolymer.", "A Hewlett-Packard Model 1090 chromatograph with a 1047A refractive index detector was used.", "The chromatograph was equipped with four 300 mm×7.5 mm Polymer Laboratories SEC columns packed with five micron particles.", "These consisted of two columns with 10 5 angstrom pore size, one column with 10 4 angstrom pore size, and one with mixed pore sizes.", "The carrier solvent was HPLC grade tetrahydrofuran (THF) with a flow of 1 ml/min.", "Column and detector temperatures were 40° C., and run time was 45 minutes.", "Tackifier additives for use in the adhesives of this invention are chosen according to the nature of the particular rubber that is used.", "Most tackifiers may be used.", "Preferred tackifiers are resins from aliphatic petroleum derivative streams containing 5- or -6-carbon-atom dienes and mono-olefins.", "The tackifiers range from materials that are normally liquid at room temperature to those that are normally solid at room temperature.", "The resins typically contain 40 wt % or more of polymerized dienes.", "The dienes are typically piperylene and/or isoprene.", "Useful tackifiers include Escorez 1310 LC and Escorez 2520 manufactured by ExxonMobil Chemical, Piccotac 95 manufactured by Eastman Chemical, and the Wingtack resin family manufactured by Goodyear (with the numerical designation being the softening point) such as Wingtack 95, which is a solid resin having a softening point of about 95° C., and Wingtack 10, which is a liquid resin having a softening point of about 10° C. Other suitable tackifiers include resins such as aliphatic/aromatic resins, which may or may not be hydrogenated such as the products ECR 373 having a softening point of about 90° C., or Escorez 2520 having a softening point of about 20° C. manufactured by ExxonMobil Chemical.", "Hydrogenated polycyclic resins (typically dicyclopentadiene resins such as Escorez 5300, 5320, 5340 and 5380 manufactured by ExxonMobil Chemical) and the like may also be used.", "Hydrogenated polycyclic aromatic modified resins, such as Escorez 5690, 5600 and 5620, manufactured by ExxonMobil Chemical, may also be used.", "Hydrogenated aromatic resins wherein a very substantial portion, if not all, of the benzene rings are converted to cyclohexane rings (for example, the Regalrez family of resins manufactured by Eastman Chemical such as Regalrez 1018, 1033, 1065, 1078 and 1126 and Regalite R-100, and the Arkon family of resins from Arakawa Chemical such as Arkon P-85, P-100, P-115 and P-125) may also be used.", "Rosin, rosin esters, polyterpenes, and other tackifiers, which are compatible with the polyisoprene and polybutadiene phases and to some degree with the polystyrene end blocks, can also be added.", "All such tackifiers may be used in hydrogenated or unhydrogenated form.", "Other additives include plasticizing oils such as Shellflex 371, manufactured by Shell, Kaydol mineral oil, manufactured by Witco and Flexon 876 manufactured by ExxonMobil, which are soluble in both the polyisoprene and polybutadiene phases combine any upper and any lower limit.", "Typically the adhesives may contain from 5 to 20 wt %, preferably from 5 to 15 wt %, more preferably from 10 to 15 wt % of the plasticizing oil.", "Preferred ranges for the amount of plasticizing oil in this paragraph are set out above.", "Preferred ranges for the quantities set out in this paragraph may combine any upper and any lower limits set out above.", "The tackifier may be present from 50% by weight, preferably from 55%, more preferably from 60%, based on the total weight of tackifier and copolymers.", "It may be present at up to 80% by weight, preferably up to 75%, more preferably up to 70% by weight.", "Conversely, the block copolymers are present from 20%, preferably from 25%, more preferably from 30%, by weight based on the weight of the tackifier and the copolymers and up to 50%, preferably up to 45%, by weight based on the combined weight of the tackifier system and the copolymers.", "The resin additives are preferably a mixture of a normally solid tackifier such as Escorez 1310 LC and a normally liquid tackifier such as Wingtack 10 or Escorez 2520.", "Preferred ranges for the quantities set out in this paragraph may combine any upper and any lower limits set out above.", "Petroleum resins are well known and are generally produced by Friedel-Crafts or thermal polymerization of various feeds, which may be pure monomer feeds or refinery streams containing mixtures of various unsaturated materials.", "Generally speaking, the purer the feed the easier to polymerize.", "For example, pure styrene, pure α-methyl styrene and mixtures thereof are easier to polymerize than a C 8 /C 9 refinery stream.", "Similarly, pure or concentrated piperylene is easier to polymerize than C 4 to C 6 refinery streams.", "But these pure monomers are more expensive to produce than the refinery streams that are often byproducts of large volume refining.", "Aliphatic hydrocarbon resins can be prepared by cationic polymerization of a cracked petroleum feed containing C 4 , C 5 , and C 6 paraffins, olefins, and diolefins also referred to as “C 5 monomers.”", "These monomer streams are comprised of cationically polymerisable monomers such as butadiene, 1,3-pentadiene (piperylene) along with cyclopentene, pentene, 2-methyl-2-butene, 2-methyl-2-pentene, isoprene, cyclopentadiene, and dicyclopentadiene.", "The refining streams are purified usually by both fractionation and impurity removal to obtain these feeds.", "Polymerizations are catalyzed using Friedel-Crafts catalysts such as unsupported Lewis acids (for example, boron trifluoride (BF 3 ), complexes of boron trifluoride, aluminum trichloride (AICI 3 ), or alkyl-aluminum halides, particularly chloride).", "In addition to the reactive components, non-polymerisable components in the feed include saturated hydrocarbons, which can be co-distilled with the unsaturated components such as pentane, cyclopentane, or 2-methylpentane.", "This monomer feed can be co-polymerized with other C 4 or C 5 olefins or dimers.", "The feed should be purified (typically by fractionation) to remove unsaturated materials that adversely affect the polymerization reaction or cause undesirable color of the final resin (for example, isoprene).", "Generally, C 5 aliphatic hydrocarbon resins are synthesized using a piperylene concentrate stream that is fractionation-enriched to increase the piperylene content and to reduce the difficult-to-polymerize, olefin and diolefin content.", "Typically, the feed stream includes at least 20 wt %, preferably 30 wt %, more preferably 50 wt %, monomer and up to 80 wt %, preferably 70 wt %, more preferably 30 wt %, solvent.", "The solvent may be an aromatic solvent, such as toluene, xylenes, and aromatic petroleum solvents, or their mixtures.", "The solvent may include an aliphatic solvent.", "Mixtures of aromatic and aliphatic solvents may also be used.", "The solvent may also be recycled.", "The solvent may be a non-polymerisable feed component.", "The feedstream may include at least C 4 to C 6 monomers, in which cyclopentadiene and methylcyclopentadiene components may be removed from the feed stream by heating at a temperature between 100° C. and 160° C. and fractionally distilling.", "The monomers may include at least one of isobutylene, butadiene, 2-methyl-2-butene, 1-pentene, 2-methyl-1-pentene, 2-methyl-2-pentene, 2-pentene, cyclopentene, isoprene, cyclohexene, 1,3-pentadiene, 1,4-pentadiene, isoprene, 1,3-hexadiene, 1,4-hexadiene, cyclopentadiene, and dicyclopentadiene.", "In accordance with another aspect, the feed stream can include at least 30 wt %, preferably 50 wt %, of C 5 monomers, as described above and at least 5 wt %, preferably 15 wt % of a co-feed including at least one of pure monomer, C 9 monomers, and terpenes.", "Likewise, the feed stream can include up to 95 wt %, preferably 85 wt % of C 5 monomers, as described above and 70 wt %, preferably 50 wt %, of a co-feed including at least one of pure monomer, C 9 monomers, and terpenes.", "The feed may also contain an aromatic olefin.", "Preferred aromatic olefins are those such as styrene, indene, and their derivatives.", "Particularly preferred aromatic olefins include styrene, α-methylstyrene, β-methylstyrene, indene, substituted indenes, such as methylindenes, and vinyl toluenes.", "The aromatic olefins are typically present at levels of at least 1 wt %, and at up to 50 wt %, more preferably 30 wt %, even more preferably 10 wt %.", "Polymerizations may be continuous or batch processes.", "A batch process reaction time is usually at least 30 minutes, preferably 60 minutes, and no greater than 8 hours, preferably 4 hours at a reaction temperature.", "Polymerization temperatures range from −50° C. to 150° C., preferably −20° C. to 100° C. Temperature significantly affects resin properties.", "Higher-molecular-weight and high-softening-point resins are prepared at lower reaction temperatures.", "Polymerization may be stopped by removing the catalyst from the hydrocarbon resin, for example, by filtration.", "The hydrocarbon resin may be removed from a fixed bed reactor, which includes the catalyst.", "The hydrocarbon resin may be stripped to remove unreacted monomers, solvents, and low-molecular-weight oligomers.", "The unreacted monomers, solvents, and low-molecular-weight oligomers may be recycled.", "The monomer feed can be co-polymerized with C 4 or C 5 olefin or dimers as chain transfer agents.", "Up to 40 wt % preferably up to 20 wt % of chain transfer agents may be added to obtain resins with lower molecular weight and narrower molecular weight distributions than can be prepared using the monomer feed alone.", "Chain transfer agents terminate polymer chain growth such that polymer initiation sites regenerate.", "Components that behave as chain transfer agents in these reactions include but are not limited to isobutylene, 2-methyl-1-butene, 2-methyl-2-butene, or dimers or oligomers of these species.", "The chain transfer agent can be added to the reaction in pure form or diluted in a solvent.", "Preferred solvents are aromatic solvents—typically toluene, xylenes, or light aromatic petroleum solvents.", "These solvents can be used fresh or recycled from the process.", "The solvents generally contain less than 200 ppm water, preferably less than 100 ppm water, and most preferably less than 50 ppm water.", "Typically, the resulting resin has a number average molecular weight (Mn) of at least 400, a weight average molecular weight (Mw) of at least 500, a Z average molecular weight (Mz) of at least 700, and a polydispersity (PD) as measured by Mw/Mn of at least 1.5 where Mn, Mw, and Mz are determined by Gel permeation chromatography.", "Similarly, the resin has a number average molecular weight (Mn) up to 2,000, a weight average molecular weight (Mw) of up to 3500, a Z average molecular weight (Mz) of up to 15,000 and a polydispersity (PD) as measured by Mw/Mn up to 4.", "Where hydrogenated resins are used, the hydrogenation may be carried out via molten resin or resin solution-based processes by either batch wise or, more commonly, continuous processes.", "Supported monometallic and bimetallic catalysts based on group-6, -8, -9, -10 or -11 elements are typically used for hydrocarbon resin hydrogenation.", "Catalysts such as supported nickel (for example, nickel on alumina, nickel on charcoal, nickel on silica, nickel on kieselguhr, etc), supported palladium (for example, palladium on silica, palladium on charcoal, palladium on magnesium oxide, etc) and supported copper and/or zinc (for example, copper chromite on copper and/or manganese oxide, copper and zinc on alumina, etc.) are good hydrogenation catalysts.", "The support material typically consists of porous inorganic refractory oxides such as silica, magnesia, silica-magnesia, zirconia, silica-zirconia, titania, silica-titania, alumina, silica-alumina, alumina-silicate, etc, with supports containing γ-alumina being highly preferred.", "Preferably, the supports are essentially free of crystalline molecular sieve materials.", "Mixtures of the foregoing oxides are also contemplated, especially homogeneous mixtures.", "Among the useful support materials in the present invention are the supports disclosed in the U.S. Pat. Nos. 4,686,030, 4,846,961, 4,500,424, and 4,849,093.", "Preferred supports include alumina, silica, carbon, MgO, TiO 2 , ZrO 2 , FeO 3 or their mixtures.", "Any of the known processes for catalytically hydrogenating hydrocarbon resins can be used;", "particularly the processes of U.S. Pat. Nos. 5,171,793, 4,629,766, 5,502,104 and 4,328,090 and WO 95/12623.", "Generic hydrogenation conditions include reaction temperatures of 100° C.-350° C. and hydrogen pressures of 5 atmospheres (506 kPa)-300 atmospheres (30390 kPa), for example, 10 to 275 atm (1013 kPa to 27579 kPa).", "A preferred hydrogenation temperature is in the range 180° C. to 320° C. and a preferred pressure is in the range 15195 kPa to 20260 kPa hydrogen.", "The hydrogen-to-feed volume ratio to the reactor under standard conditions (25° C., 1 atm (101 kPa) pressure) typically can range from 20-200.", "For water-white resins 100-200 is preferred.", "Another suitable process for resin hydrogenation is described in EP 0082726.", "EP 0082726 describes hydrogenation of a catalytic or thermal petroleum resin using nickel-tungsten catalyst on a γ-alumina support where the hydrogen pressure is 1.47×10 7 -1.96×10 7 Pa and the temperature ranges from 250-330° C. Thermal hydrogenation is usually performed at 160° C. to 320° C., at a pressure of 9.8×10 5 to 11.7×10 5 Pa and for a period typically of 1.5 to 4 hours.", "After hydrogenation, the reactor mixture may be flashed and further separated to recover the resin.", "Steam distillation may be used to eliminate oligomers, preferably without exceeding 325° C. In a particularly preferred embodiment, the catalyst comprises nickel and/or cobalt on one or more of molybdenum, tungsten, alumina or silica supports.", "In a preferred embodiment, the amount of nickel oxide and/or cobalt oxide on the support ranges from 2 to 10 wt %.", "The amount of tungsten or molybdenum oxide on the support after preparation ranges from 5 to 25 wt %.", "Preferably, the catalyst contains 4 to 7 wt % nickel oxide and 18 to 22 wt % tungsten oxide.", "This process and suitable catalysts are described in greater detail in U.S. Pat. No. 5,820,749.", "In another preferred embodiment, the hydrogenation may be carried out using the process and catalysts described in U.S. Pat. No. 4,629,766.", "In particular, nickel-tungsten catalysts on γ-alumina are preferred.", "While the pressure-sensitive adhesive formulations of the present invention exhibit excellent low temperature and ambient temperature performance as well as good die-cutting performance, they may also enhance elevated temperature performance.", "This may be accomplished by cross-linking techniques such as the use of electron beam (EB) radiation and ultraviolet (UV) radiation and chemical cross-linking.", "If employed, tackifying additives should be substantially saturated so that all of the energy of cure goes into cross-linking of the adhesives'", "elastomeric components.", "The adhesive formulations may also contain additives well known in the art such as anti-block, anti-static, antioxidants, UV stabilizers, neutralizers, lubricants, surfactants, anti-nucleating agents and/or fillers.", "Preferred additives include silica, titanium dioxide, polydimethylsiloxane, talc, dyes, wax, calcium stearate, calcium carbonate, carbon black, barium sulphate and magnesium silicate.", "The adhesives of the invention may be used as pressure sensitive adhesives, hot melt adhesives or contact adhesives and used in applications such as tapes, labels, paper impregnation, hot-melt adhesives, including woodworking, packaging, bookbinding or disposables, sealants, rubber compounds, pipe wrapping, carpet backing, contact adhesives, road-marking or tire construction.", "They are particularly useful as hot-melt pressure sensitive adhesives used for labels where they impart improved die-cutting performance, and also improved adhesive properties, particularly improved shear performance.", "In the Examples which follow, the block copolymers used in the adhesive formulations were prepared by the process described in WO 95/14727 and the desired ratio of radial and diblock copolymers was obtained by varying the amount of coupling agent and/or by blending.", "The procedures for the preparation of the hot melt adhesive blends, and of the coatings as well as the testing of the adhesive performances were as follow.", "The hot melt pressure sensitive adhesives were prepared by mixing the block copolymers with the tackifying resins in a laboratory z blade mixer of 300 ml capacity, at a temperature of about 145° C. A small amount of phenolic antioxidant was added to the blend to prevent its degradation during the blending process.", "The total mixing time was about 70 minutes.", "The tackifiers used were Escorez 1310 and ECR 373 from ExxonMobil Chemical and Wingtack 10 from Goodyear.", "Final blend viscosity was evaluated with a Brookfield viscosimeter according to a procedure based on ASTM D 3236-88.", "The pressure sensitive adhesives were applied as a hot melt to a silicone coated paper at a coating weight of about 20 grams/sq meter, using an Acumeter laboratory coater with a slot die for extrusion of the molten adhesive at a temperature of 165° C. The lamination was done according to industry practice, by transfer coating from the silicone coater paper release substrate to an 80 g/sq meter vellum paper frontal substrate.", "The adhesive performances were evaluated according to test methods published by FINAT, P.O. Box 85612 NL-2508 CH, The Hague, for example, FTM 1 for the peel adhesion at 180 degree FTM 9 for the loop tack measurements FTM 7 for the shear resistance Migration was evaluated by comparing the whiteness of the paper frontal substrate after ageing at 60° C. and 70° C. for one and two weeks.", "The whiteness was evaluated with a Hunterlab spectrophotometer.", "Dynamic theological properties at 20° C. were determined on RDAII and SR-500 instruments manufactured by Rheometric Scientific, Piscataway, N.J. The former gives access to frequencies between 10 −2 to 100 rad.", "s −1 and temperatures lower than 20° C. (down to −70° C.) to reach the glassy region obtained at higher frequencies.", "The SR-500 instrument, which covers a frequency range between 10 −5 to 100 rad.", "s −1 at room temperature, was used for the terminal zone (lower frequencies).", "We used plate-plate geometry for all experiments.", "The diameter of the plate decreases from 25 mm to 5 mm as temperature decreases in order to maintain the actual rheometer torque between measurable limits.", "Frequency sweeps were carried out at deformation levels well within the linear viscoelastic region.", "In order to broaden the range of accessible experimental frequencies, time-temperature superposition was applied with care.", "Measurements in the range of frequencies 10 −5 to 10 +2 were made at 20° C. To reach higher frequencies experiments at lower temperature were performed and the measurements extrapolated to 20° C. To ensure that experiments were conducted on bubble-free specimens, samples were degassed overnight under primary vacuum at about 90° C. Disks of adequate diameter were then compression molded, at a temperature systematically lower than the mixing temperature.", "EXAMPLES The following Examples A and B illustrate the Production of High Diblock/Radial Block copolymer Mixtures via control of coupling efficiency.", "Example A To a 5-gallon stirred reactor under a nitrogen atmosphere were added 12.5 kg of cyclohexane solvent and 84.0 g of a 0.17 M solution of sec-butyl lithium in cyclohexane.", "The temperature of the reactor was brought to 75° C. and 339 g of styrene was added.", "Polymerization of the styrene was allowed to continue for 36 minutes.", "The reaction mixture was cooled to 57° C. and 1692 g of isoprene was added.", "The isoprene was allowed to polymerize for 46 minutes, during which the reaction temperature reached a maximum of 92° C. At the end of the 46 minutes, 10 grams of butadiene was added at 71° C. and it was allowed to polymerize for an additional 34 minutes.", "Then 1.0 g of 0.87 M SiCl 4 in cyclohexane was added all at once.", "The reaction was allowed to continue for another 26 minutes before the reaction was terminated by addition of 3.0 ml of isopropanol.", "The resulting polymer was analyzed by GPC, and found to contain 82.0% diblock and 18.0% coupled radial block polymer.", "The radial block copolymer had 84% four arms, 16% three arms and no detectable two arms material.", "The styrene content was 16.6 wt % and the molecular weight of the diblock was 78,150.", "Example B To a 5-gallon stirred reactor under a nitrogen atmosphere were added 12.5 kg of cyclohexane solvent and 79.1 g of a 0.17 M solution of sec-butyl lithium in cyclohexane.", "The temperature of the reactor was brought to 82° C. and 339 g of styrene was added.", "Polymerization of the styrene was allowed to continue for 37 minutes.", "The reaction mixture was cooled to 58° C. and 1692 g of isoprene was added.", "The isoprene was allowed to polymerize for 26 minutes, during which the reaction temperature reached a maximum of 95° C. At the end of the 26 minutes, 10 grams of butadiene was added at 71° C. and it was allowed to polymerize for an additional 43 minutes.", "Then 3.1 g of 0.87 M SiCl 4 in cyclohexane was added all at once.", "The reaction was allowed to continue for another 31 minutes before the reaction was terminated by addition of 3.0 ml of isopropanol.", "The resulting polymer was analyzed by GPC, and found to contain 49.1% diblock, about 1% polystyrene homopolymer and the remainder coupled radial block polymer.", "The radial block copolymer had 78% four-arm and 15% three-arm, with the remainder two-arm materials.", "The styrene content was 16.6 wt % and the molecular weight of the diblock was 80,125.", "The following additional Examples illustrate adhesive systems according to the present invention.", "Styrene-isoprene four arms radial block copolymers having different contents of styrene-isoprene diblock copolymers and similar overall styrene content were used in a hot melt formulation containing 31 wt % total of block copolymer, 27 wt % of Wingtack 10, and 42 wt % of Escorez 1310 to which was added 0.4 wt % of Irganox 1076.", "The resulting hot melts show the following characteristics: Comparative Example 1 Example 2 Example 3 Example 4 Example 5 Radial polymer molecular 268000 290800 328000 332000 300000 weight Diblock molecular weight 67000 72700 82000 83000 75000 Styrene content (wt %) 20.5 17 18 17.8 17 Diblock content (wt %) 31 60 70 76 88 Brookfield Viscosity 6200 4960 5650 4460 1560 (175° C. - mPa · s) 180° peel strength - N/25 mm Room temperature - glass 29 cf 33.5 af 34.1 pt 36 29.5 cf 3° C. - glass 22 pt 18 pt 24 pt 22.6 pt Room temperature - PE 20.5 af 21 af 27 cf + pt 26 26 cf + pt 3° C. - PE 18.5 pt 18.5 pt 25 pt 21 pt Loop Tack - N glass at room temperature 23.5 af 22 af 28.3 af 37 38 cf glass at 3° C. 15 pt 6.5 af 15 pt 0.7 af 17 pt Loop Tack - N Polyethylene at room 18 af 14 af 21.2 af 24 af 24 af temperature Polyethylene at 3° C. 6.5 j 16.5 j + pt 5.0 j 18 pt Shear - room temperature - hours Steel - 25 × 25 mm - 1 kg >175 85-170 cf >150 cf 22-150 cf 3 cf Migration - % reflection 1 week 60° C. 90 88.5 86.9 89.5 87 2 weeks 60° C. 87 84 84.2 89 87.5 1 week 70° C. 82.5 85 83.8 82 80 2 weeks 70° C. 80 77 80.6 68 79 Rheology Frequency where G′ = 1000 1 10 −1 1.7 10 −1 1.1 10 −1 1.7 10 −1 3 10 −1 Pa (rad/s) * Tan delta at frequency 1.3 0.56 0.97 0.7 1.22 where G′ = 10,000 Pa * pt means paper tear cf means cohesive failure af means adhesive failure j means jerking * when measured at 20° C. FIG. 3 compares G′ of comparative Example 1, a standard hot melt pressure sensitive based on pure triblock copolymer and an acrylic based adhesive.", "The HMPSA adhesives of this invention have low viscosity, high shear properties for radials up to 80% diblock content, associated with excellent tack and peel performances at room and low temperature.", "The dynamic rheological properties are shown in FIG. 4 , where they are compared with those of Comparative Example 1.", "As it can be seen, the plateau modulus at low frequencies is decreasing when the level of diblock in the radial copolymer is increasing.", "The systems of the present invention have much lower moduli than the product of comparative Example 1.", "G′ intersects a value of 10000 Pa at frequencies higher than 10 −3 rad/s.", "At such frequencies Tan delta varies preferably from 0.35 to 1.22, preferably 0.56 to 1.22, when measured at 20° C. The die-cutting performance of the adhesive of Example 4 was tested on a printing die-cutting machine, and was compared with a commercial Hot Melt Pressure Sensitive formulation based on linear block copolymers having an overall diblock content of 75% and with an acrylic based adhesive.", "The tests were performed using different types of die shapes.", "The results are shown in FIG. 5 .", "The results shown in FIG. 5 , demonstrate that the reduced elastic behavior as shown in FIG. 4 (lower plateau modulus, higher loss factor Tan delta) provide to hot melt pressure sensitive adhesives based on radial copolymer with high diblock content significantly better die-cutting performance than commercially available copolymer based adhesive formulations and is close to the die-cutting behavior of acrylic based adhesives.", "We have also found that the radial block copolymer mixtures of the present invention have lower tensile strength and are softer and tackier than the previous mixtures with lower diblock content.", "This renders the polymers useful in applications such as sound deadening, shock absorption and polymer modification." ]
PRIORITY CLAIM This patent is a continuation-in-part of U.S. patent application Ser. No. 14/183,134 entitled “GAS REFRACTION COMPENSATION FOR LASER-SUSTAINED PLASMA BULBS” filed Feb. 18, 2014, which claims priority to U.S. Provisional Patent Application No. 61/767,917 filed Feb. 22, 2013, which are incorporated herein by reference. BACKGROUND 1. Field of the Invention The present invention relates to laser-sustained plasma illuminator systems. More particularly, the invention relates to systems and methods for compensating for optical aberrations to optimize plasma performance and UV light collection. 2. Description of Related Art Plasmas sustained by lasers have shapes defined by the laser light intensity distribution near the laser focus. The laser light intensity distribution may be a function of optical aberrations (e.g., how well the light is focused in the plasma cell). Many optical aberrations present in typical laser-sustained plasma illuminator systems are aberrations introduced by an enclosure (e.g., a bulb) used to contain the gas and the plasma. Such bulb-introduced aberrations may be significant optical aberrations, especially for plasmas sustained by lasers operating in the near IR range (wavelengths of about 1000 nm). These significant optical aberrations may result in large size plasmas, the inability to control the bulb envelope, and/or irreproducible plasma shapes. FIG. 1 depicts different plasma shapes resulting from various optical abberrations of a pump beam in different bulbs. Shape 100 results from a pump beam with significant aberrations. These significant aberrations produce a conventional shaped plasma for shape 100 . Shape 102 results from a pump beam with less aberrations. These fewer aberrations may produce a spherical shaped plasma for shape 102 . Shape 104 results from a pump beam with the fewest aberrations. Shape 104 may be the smallest and brightest plasma shape of the three shapes depicted in FIG. 1 because of the fewest aberrations (e.g., shape 104 may be a “compensated” plasma shape or plasma shape that results after compensating for aberrations). Aberrations may become particularly large when a high NA (numerical aperture) is used for pumping the plasma. Large pump laser NAs are used as light sources in many current laser-sustained plasma illuminator systems. U.S. Pat. No. 7,705,331 to Kirk et al., which is incorporated by reference as if fully set forth herein, describes an example of a high NA system. FIG. 2 depicts an example of a laser-sustained light source with a high NA. Light source 200 may include laser 202 , turn mirror 204 , cold mirror 206 , homogenizer 208 , filters 210 , ellipse 212 , and enclosure 214 . Enclosure 214 may be, for example, a bulb. Ignition cable 216 may be coupled to enclosure 214 . Plasma 217 may be generated inside enclosure 214 at or near a focal point of ellipse 212 . As shown in FIG. 2 , light from laser 202 (e.g., light 218 ) may be reflected off ellipse 212 and focused in the middle of enclosure 214 at plasma 217 . Broad-band UV light (e.g., light 220 ) from homogenizer 208 may be reflected by cold mirror 206 , reflected off ellipse 212 , and focused in the middle of enclosure 214 at plasma 217 . Light passing through enclosure 214 may be used to excite and/or sustain plasma 217 inside the enclosure. Plasma 217 inside enclosure 214 may provide light for illumination of a specimen for a process performed on the specimen (e.g., an inspection process performed on the specimen). As shown in FIG. 2 , light passing through enclosure 214 may have a high NA. In addition to the aberrations introduced by the enclosure itself, the refractive index of the gas inside the enclosure is another source of aberrations in the system. Gas related aberrations may be especially significant in high-pressure enclosures. FIG. 3 depicts images taken of a bulb at different pressures of Xe (xenon) in the bulb. As shown in FIG. 3 , aberrations seen from the bulb increase with increasing pressure. U.S. Pub. Pat. Appl. Nos. 2007/0228288 and 2007/0228300 to Smith, each of which is incorporated by reference as if fully set forth herein, disclose one method of compensating for aberrations introduced by the refractive index of the walls of the enclosure by modifying the shape of the reflector (e.g., a reflective ellipse). Modifying the shape of the reflector, however, can only account for aberrations from reproducible enclosure shapes. Modifying reflector shapes for each individual enclosure shape and/or different fill pressures is difficult to impractical to implement for most laser-sustained plasma illuminator systems. SUMMARY In certain embodiments, a laser-sustained plasma illuminator system includes at least one laser light source to provide light. At least one reflector focuses the light from the laser light source at a focal point of the reflector. An enclosure substantially filled with a gas is positioned at or near the focal point of the reflector. The light from the laser light source at least partially sustains a plasma contained in the enclosure. The enclosure has at least one wall with at least one property that is varied. The at least one property of the wall may be varied to compensate for optical aberrations in the system. In some embodiments, a thickness of the wall is varied. In some embodiments, a refractive index of the wall is varied. In certain embodiments, a method for compensating for optical aberrations in a laser-sustained plasma illuminator system includes providing an enclosure for containing a plasma to the laser-sustained plasma illuminator system. The enclosure may have at least one wall with at least one property that is varied to compensate for optical aberrations in the system. In certain embodiments, a laser-sustained plasma illuminator system includes at least one laser light source to provide light. At least one reflector focuses the light from the laser light source at a focal point of the reflector. An enclosure may include two or more different materials and be substantially filled with a gas positioned at or near the focal point of the reflector. The light from the at least one laser light source at least partially sustains a plasma contained in the enclosure. The enclosure has at least one wall formed from the two or more different materials with at least one property of the wall being varied. BRIEF DESCRIPTION OF THE DRAWINGS Features and advantages of the methods and apparatus of the present invention will be more fully appreciated by reference to the following detailed description of presently preferred but nonetheless illustrative embodiments in accordance with the present invention when taken in conjunction with the accompanying drawings in which: FIG. 1 depicts different plasma shapes resulting from various optical abberrations of a pump beam in different bulbs. FIG. 2 depicts an example of a laser-sustained light source with a high numerical aperture (NA). FIG. 3 depicts images taken of a bulb at different pressures of Xe (xenon) in the bulb. FIG. 4A depicts an embodiment of an ideal enclosure with no compensation needed. FIG. 4B depicts an embodiment of an enclosure with shape induced aberrations and no compensation. FIG. 4C depicts an embodiment of an enclosure with walls having varying thickness to compensate for enclosure shape aberrations. FIG. 4D depicts an embodiment of an enclosure with walls having varying refractive index to compensate for enclosure shape aberrations. FIG. 4E depicts an embodiment of an enclosure made of two different materials. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. The drawings may not be to scale. It should be understood that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but to the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. DETAILED DESCRIPTION OF EMBODIMENTS One or more properties of a wall of an enclosure (e.g., a bulb) may be varied (e.g. adjusted) to compensate for optical aberrations such as shape aberrations in the enclosure and/or aberrations induced by the gas refractive index (e.g., fill pressure aberrations). In certain embodiments, the wall thickness of the enclosure is adjusted to compensate for optical aberrations. FIG. 4A depicts an embodiment of an ideal enclosure with no compensation needed. Enclosure 400 A has no aberrations in shape and no gas induced aberrations. Thus, all light from pump laser 402 is focused at plasma 404 . FIG. 4B depicts an embodiment of an enclosure with shape induced aberrations and no compensation. Enclosure 400 B has shape aberrations that, without compensation, cause some light from pump laser 402 to not be focused at plasma 404 (e.g., light 406 ). FIG. 4C depicts an embodiment of an enclosure with walls having varying thickness to compensate for enclosure shape aberrations. Enclosure 400 C has walls 408 with varying thickness. The varying thickness of walls 408 compensates for any enclosure shape aberrations and/or fill pressure aberrations to focus light from pump laser 402 at plasma 404 . For example, as shown in FIG. 4C , light 406 is now focused at plasma 404 . In certain embodiments, enclosure 400 C is a bulb. The bulb may be, for example, a lamp made of glass (fused silica) using a bulb-specific manufacturing process. In some embodiments, enclosure 400 C is any other type of enclosure, vessel, or container that encloses/contains gas and has walls made of a transparent material. Enclosure 400 C may be an enclosure made of glass, quartz, sapphire, CaF 2 , MgF 2 , or similar materials with proper sealing to enclose/contain a gas. For example, enclosure 400 C may be a tube or cell made of glass with sealing to enclose a gas. In certain embodiments, the thickness variation in walls 408 (e.g., the shape of the walls as defined by changes in the wall thickness along a section of the wall) is defined based on the shape of the envelope of enclosure 400 C and/or the gas fill pressure of the enclosure. Varying the thickness of the walls of enclosures (e.g., walls 408 of enclosure 400 C) to compensate for aberrations in the enclosures (e.g., enclosure wall thickness compensation) allows a single uncompensated reflector to be used for all types of enclosures with varying shapes and/or fill pressures. Thus, a laser-sustained plasma illuminator system using enclosures with enclosure wall thickness compensation may have improved performance and/or improved cost efficiency compared to typical current laser-sustained plasma illuminator systems (e.g., systems using modified reflector shapes for aberration compensation). In some embodiments, enclosure wall thickness compensation is used to compensate for aberrations in the collected light path (e.g., the path of light before the light enters the enclosure or the path of light from the light source (laser) through focusing optics (such as mirrors and/or reflectors). In some embodiments, enclosure wall thickness compensation is used to introduce a controlled amount of aberration into a laser-sustained plasma illuminator system. For example, wall thickness may be varied to provide a controlled amount of aberration to optimize plasma performance in the laser-sustained plasma illuminator system. In some embodiments, enclosure wall thickness compensation is used in combination with other compensation methods. Combining enclosure wall thickness compensation with other compensation methods may provide higher levels of control of aberrations in a laser-sustained plasma illuminator system. For example, in one embodiment, enclosure wall thickness may be varied in combination with the shape of the enclosure. In some embodiments, enclosure wall thickness compensation is combined with compensation using modified reflector shapes to provide greater control of the shape of the plasma. In certain embodiments, the refractive index of the enclosure is adjusted to compensate for optical aberrations. FIG. 4D depicts an embodiment of an enclosure with walls having varying refractive index to compensate for enclosure shape aberrations. Enclosure 400 D may be a bulb or any other type of enclosure, vessel, or container that encloses/contains gas and has walls made of a transparent material as described above. Enclosure 400 D may be an enclosure made of glass, quartz, sapphire, CaF 2 , MgF 2 , or similar materials with proper sealing to enclose/contain a gas. In certain embodiments, enclosure 400 D includes walls 408 ′ with varying refractive index. Varying the refractive index of walls 408 ′ compensates for any enclosure shape aberrations and/or fill pressure aberrations to focus light from pump laser 402 at plasma 404 . For example, as shown in FIG. 4D , light 406 is focused at plasma 404 . In some embodiments, the refractive index of walls 408 ′ of enclosure 400 D is varied by varying (e.g. altering) the chemical content of materials used in the walls. For example, one or more materials used in walls 408 ′ may be doped to alter the chemical content (or composition) of the walls. The dopant(s) concentration in walls 408 ′ may be varied to provide a tailored or controlled refractive index profile in the walls. For example, the dopant concentration may provide one or more abrupt transitions (changes) in refractive index in walls 408 ′ or the dopant concentration may provide a gradual change in refractive index in the walls. In some embodiments, the refractive index of walls 408 ′ of enclosure 400 D is varied by varying (e.g. altering) a structure (e.g., physical and/or chemical structure) of the walls. For example, the structure of walls 408 ′ may be changed (altered) to be more or less porous to vary the refractive index of the walls. In some embodiments, the refractive index of walls 408 ′ of enclosure 400 D is varied by varying a temperature along the walls. For example, differences in temperature along walls 408 ′ may provide different refractive indices along the walls depending on the material used for the walls. In some embodiments, walls 408 ′ have selected (e.g., patterned) absorption along the walls to vary the temperature along the walls. In some embodiments, walls 408 ′ have selected (e.g., patterned) cooling flow along the walls to vary the temperature along the walls. In certain embodiments, an enclosure (such as enclosure 400 C or enclosure 400 D described above) is formed by combining two or more different materials. The combination of two or more different materials may be used to form an enclosure with varying wall thickness (e.g., enclosure 400 C) or an enclosure with varying refractive index (e.g., enclosure 400 D). For example, the refractive index of walls 408 ′ of enclosure 400 D may be varied by combining two or more different refractive index materials to form the walls of the enclosure. FIG. 4E depicts an embodiment of enclosure 400 D′ made of two different materials. Enclosure 400 D′ includes walls 408 ″. Walls 408 ″ may include two different materials 410 A, 410 B. In certain embodiments, material 410 A has a different refractive index from material 410 B. The different refractive indices of materials 410 A, 410 B may provide a varying refractive index in walls 408 ″ of enclosure 400 D′. In certain embodiments, enclosure 400 D′ is formed by coupling, connecting, or attaching together two or more enclosures made of the different materials (e.g., materials 410 A, 410 B) to form the enclosure. For example, a first enclosure may include material 410 A and a second enclosure may include material 410 B and enclosure 400 D′ is formed by coupling together the first enclosure and the second enclosure. In some embodiments, the enclosures of the different materials are concentric enclosures such as concentric cylindrical enclosures. It is to be understood the invention is not limited to particular systems described which may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. As used in this specification, the singular forms “a”, “an” and “the” include plural referents unless the content clearly indicates otherwise. Thus, for example, reference to “a wall” includes a combination of two or more walls and reference to “a gas” includes mixtures of gases. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims.
A laser-sustained plasma illuminator system includes at least one laser light source to provide light. At least one reflector focuses the light from the laser light source at a focal point of the reflector. An enclosure substantially filled with a gas is positioned at or near the focal point of the reflector. The light from the laser light source at least partially sustains a plasma contained in the enclosure. The enclosure has at least one wall with at least one property that is varied to compensate for optical aberrations in the system.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "PRIORITY CLAIM This patent is a continuation-in-part of U.S. patent application Ser.", "No. 14/183,134 entitled “GAS REFRACTION COMPENSATION FOR LASER-SUSTAINED PLASMA BULBS”", "filed Feb. 18, 2014, which claims priority to U.S. Provisional Patent Application No. 61/767,917 filed Feb. 22, 2013, which are incorporated herein by reference.", "BACKGROUND 1.", "Field of the Invention The present invention relates to laser-sustained plasma illuminator systems.", "More particularly, the invention relates to systems and methods for compensating for optical aberrations to optimize plasma performance and UV light collection.", "Description of Related Art Plasmas sustained by lasers have shapes defined by the laser light intensity distribution near the laser focus.", "The laser light intensity distribution may be a function of optical aberrations (e.g., how well the light is focused in the plasma cell).", "Many optical aberrations present in typical laser-sustained plasma illuminator systems are aberrations introduced by an enclosure (e.g., a bulb) used to contain the gas and the plasma.", "Such bulb-introduced aberrations may be significant optical aberrations, especially for plasmas sustained by lasers operating in the near IR range (wavelengths of about 1000 nm).", "These significant optical aberrations may result in large size plasmas, the inability to control the bulb envelope, and/or irreproducible plasma shapes.", "FIG. 1 depicts different plasma shapes resulting from various optical abberrations of a pump beam in different bulbs.", "Shape 100 results from a pump beam with significant aberrations.", "These significant aberrations produce a conventional shaped plasma for shape 100 .", "Shape 102 results from a pump beam with less aberrations.", "These fewer aberrations may produce a spherical shaped plasma for shape 102 .", "Shape 104 results from a pump beam with the fewest aberrations.", "Shape 104 may be the smallest and brightest plasma shape of the three shapes depicted in FIG. 1 because of the fewest aberrations (e.g., shape 104 may be a “compensated”", "plasma shape or plasma shape that results after compensating for aberrations).", "Aberrations may become particularly large when a high NA (numerical aperture) is used for pumping the plasma.", "Large pump laser NAs are used as light sources in many current laser-sustained plasma illuminator systems.", "U.S. Pat. No. 7,705,331 to Kirk et al.", ", which is incorporated by reference as if fully set forth herein, describes an example of a high NA system.", "FIG. 2 depicts an example of a laser-sustained light source with a high NA.", "Light source 200 may include laser 202 , turn mirror 204 , cold mirror 206 , homogenizer 208 , filters 210 , ellipse 212 , and enclosure 214 .", "Enclosure 214 may be, for example, a bulb.", "Ignition cable 216 may be coupled to enclosure 214 .", "Plasma 217 may be generated inside enclosure 214 at or near a focal point of ellipse 212 .", "As shown in FIG. 2 , light from laser 202 (e.g., light 218 ) may be reflected off ellipse 212 and focused in the middle of enclosure 214 at plasma 217 .", "Broad-band UV light (e.g., light 220 ) from homogenizer 208 may be reflected by cold mirror 206 , reflected off ellipse 212 , and focused in the middle of enclosure 214 at plasma 217 .", "Light passing through enclosure 214 may be used to excite and/or sustain plasma 217 inside the enclosure.", "Plasma 217 inside enclosure 214 may provide light for illumination of a specimen for a process performed on the specimen (e.g., an inspection process performed on the specimen).", "As shown in FIG. 2 , light passing through enclosure 214 may have a high NA.", "In addition to the aberrations introduced by the enclosure itself, the refractive index of the gas inside the enclosure is another source of aberrations in the system.", "Gas related aberrations may be especially significant in high-pressure enclosures.", "FIG. 3 depicts images taken of a bulb at different pressures of Xe (xenon) in the bulb.", "As shown in FIG. 3 , aberrations seen from the bulb increase with increasing pressure.", "U.S. Pub.", "Pat. Appl.", "Nos. 2007/0228288 and 2007/0228300 to Smith, each of which is incorporated by reference as if fully set forth herein, disclose one method of compensating for aberrations introduced by the refractive index of the walls of the enclosure by modifying the shape of the reflector (e.g., a reflective ellipse).", "Modifying the shape of the reflector, however, can only account for aberrations from reproducible enclosure shapes.", "Modifying reflector shapes for each individual enclosure shape and/or different fill pressures is difficult to impractical to implement for most laser-sustained plasma illuminator systems.", "SUMMARY In certain embodiments, a laser-sustained plasma illuminator system includes at least one laser light source to provide light.", "At least one reflector focuses the light from the laser light source at a focal point of the reflector.", "An enclosure substantially filled with a gas is positioned at or near the focal point of the reflector.", "The light from the laser light source at least partially sustains a plasma contained in the enclosure.", "The enclosure has at least one wall with at least one property that is varied.", "The at least one property of the wall may be varied to compensate for optical aberrations in the system.", "In some embodiments, a thickness of the wall is varied.", "In some embodiments, a refractive index of the wall is varied.", "In certain embodiments, a method for compensating for optical aberrations in a laser-sustained plasma illuminator system includes providing an enclosure for containing a plasma to the laser-sustained plasma illuminator system.", "The enclosure may have at least one wall with at least one property that is varied to compensate for optical aberrations in the system.", "In certain embodiments, a laser-sustained plasma illuminator system includes at least one laser light source to provide light.", "At least one reflector focuses the light from the laser light source at a focal point of the reflector.", "An enclosure may include two or more different materials and be substantially filled with a gas positioned at or near the focal point of the reflector.", "The light from the at least one laser light source at least partially sustains a plasma contained in the enclosure.", "The enclosure has at least one wall formed from the two or more different materials with at least one property of the wall being varied.", "BRIEF DESCRIPTION OF THE DRAWINGS Features and advantages of the methods and apparatus of the present invention will be more fully appreciated by reference to the following detailed description of presently preferred but nonetheless illustrative embodiments in accordance with the present invention when taken in conjunction with the accompanying drawings in which: FIG. 1 depicts different plasma shapes resulting from various optical abberrations of a pump beam in different bulbs.", "FIG. 2 depicts an example of a laser-sustained light source with a high numerical aperture (NA).", "FIG. 3 depicts images taken of a bulb at different pressures of Xe (xenon) in the bulb.", "FIG. 4A depicts an embodiment of an ideal enclosure with no compensation needed.", "FIG. 4B depicts an embodiment of an enclosure with shape induced aberrations and no compensation.", "FIG. 4C depicts an embodiment of an enclosure with walls having varying thickness to compensate for enclosure shape aberrations.", "FIG. 4D depicts an embodiment of an enclosure with walls having varying refractive index to compensate for enclosure shape aberrations.", "FIG. 4E depicts an embodiment of an enclosure made of two different materials.", "While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.", "The drawings may not be to scale.", "It should be understood that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but to the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.", "DETAILED DESCRIPTION OF EMBODIMENTS One or more properties of a wall of an enclosure (e.g., a bulb) may be varied (e.g. adjusted) to compensate for optical aberrations such as shape aberrations in the enclosure and/or aberrations induced by the gas refractive index (e.g., fill pressure aberrations).", "In certain embodiments, the wall thickness of the enclosure is adjusted to compensate for optical aberrations.", "FIG. 4A depicts an embodiment of an ideal enclosure with no compensation needed.", "Enclosure 400 A has no aberrations in shape and no gas induced aberrations.", "Thus, all light from pump laser 402 is focused at plasma 404 .", "FIG. 4B depicts an embodiment of an enclosure with shape induced aberrations and no compensation.", "Enclosure 400 B has shape aberrations that, without compensation, cause some light from pump laser 402 to not be focused at plasma 404 (e.g., light 406 ).", "FIG. 4C depicts an embodiment of an enclosure with walls having varying thickness to compensate for enclosure shape aberrations.", "Enclosure 400 C has walls 408 with varying thickness.", "The varying thickness of walls 408 compensates for any enclosure shape aberrations and/or fill pressure aberrations to focus light from pump laser 402 at plasma 404 .", "For example, as shown in FIG. 4C , light 406 is now focused at plasma 404 .", "In certain embodiments, enclosure 400 C is a bulb.", "The bulb may be, for example, a lamp made of glass (fused silica) using a bulb-specific manufacturing process.", "In some embodiments, enclosure 400 C is any other type of enclosure, vessel, or container that encloses/contains gas and has walls made of a transparent material.", "Enclosure 400 C may be an enclosure made of glass, quartz, sapphire, CaF 2 , MgF 2 , or similar materials with proper sealing to enclose/contain a gas.", "For example, enclosure 400 C may be a tube or cell made of glass with sealing to enclose a gas.", "In certain embodiments, the thickness variation in walls 408 (e.g., the shape of the walls as defined by changes in the wall thickness along a section of the wall) is defined based on the shape of the envelope of enclosure 400 C and/or the gas fill pressure of the enclosure.", "Varying the thickness of the walls of enclosures (e.g., walls 408 of enclosure 400 C) to compensate for aberrations in the enclosures (e.g., enclosure wall thickness compensation) allows a single uncompensated reflector to be used for all types of enclosures with varying shapes and/or fill pressures.", "Thus, a laser-sustained plasma illuminator system using enclosures with enclosure wall thickness compensation may have improved performance and/or improved cost efficiency compared to typical current laser-sustained plasma illuminator systems (e.g., systems using modified reflector shapes for aberration compensation).", "In some embodiments, enclosure wall thickness compensation is used to compensate for aberrations in the collected light path (e.g., the path of light before the light enters the enclosure or the path of light from the light source (laser) through focusing optics (such as mirrors and/or reflectors).", "In some embodiments, enclosure wall thickness compensation is used to introduce a controlled amount of aberration into a laser-sustained plasma illuminator system.", "For example, wall thickness may be varied to provide a controlled amount of aberration to optimize plasma performance in the laser-sustained plasma illuminator system.", "In some embodiments, enclosure wall thickness compensation is used in combination with other compensation methods.", "Combining enclosure wall thickness compensation with other compensation methods may provide higher levels of control of aberrations in a laser-sustained plasma illuminator system.", "For example, in one embodiment, enclosure wall thickness may be varied in combination with the shape of the enclosure.", "In some embodiments, enclosure wall thickness compensation is combined with compensation using modified reflector shapes to provide greater control of the shape of the plasma.", "In certain embodiments, the refractive index of the enclosure is adjusted to compensate for optical aberrations.", "FIG. 4D depicts an embodiment of an enclosure with walls having varying refractive index to compensate for enclosure shape aberrations.", "Enclosure 400 D may be a bulb or any other type of enclosure, vessel, or container that encloses/contains gas and has walls made of a transparent material as described above.", "Enclosure 400 D may be an enclosure made of glass, quartz, sapphire, CaF 2 , MgF 2 , or similar materials with proper sealing to enclose/contain a gas.", "In certain embodiments, enclosure 400 D includes walls 408 ′ with varying refractive index.", "Varying the refractive index of walls 408 ′ compensates for any enclosure shape aberrations and/or fill pressure aberrations to focus light from pump laser 402 at plasma 404 .", "For example, as shown in FIG. 4D , light 406 is focused at plasma 404 .", "In some embodiments, the refractive index of walls 408 ′ of enclosure 400 D is varied by varying (e.g. altering) the chemical content of materials used in the walls.", "For example, one or more materials used in walls 408 ′ may be doped to alter the chemical content (or composition) of the walls.", "The dopant(s) concentration in walls 408 ′ may be varied to provide a tailored or controlled refractive index profile in the walls.", "For example, the dopant concentration may provide one or more abrupt transitions (changes) in refractive index in walls 408 ′ or the dopant concentration may provide a gradual change in refractive index in the walls.", "In some embodiments, the refractive index of walls 408 ′ of enclosure 400 D is varied by varying (e.g. altering) a structure (e.g., physical and/or chemical structure) of the walls.", "For example, the structure of walls 408 ′ may be changed (altered) to be more or less porous to vary the refractive index of the walls.", "In some embodiments, the refractive index of walls 408 ′ of enclosure 400 D is varied by varying a temperature along the walls.", "For example, differences in temperature along walls 408 ′ may provide different refractive indices along the walls depending on the material used for the walls.", "In some embodiments, walls 408 ′ have selected (e.g., patterned) absorption along the walls to vary the temperature along the walls.", "In some embodiments, walls 408 ′ have selected (e.g., patterned) cooling flow along the walls to vary the temperature along the walls.", "In certain embodiments, an enclosure (such as enclosure 400 C or enclosure 400 D described above) is formed by combining two or more different materials.", "The combination of two or more different materials may be used to form an enclosure with varying wall thickness (e.g., enclosure 400 C) or an enclosure with varying refractive index (e.g., enclosure 400 D).", "For example, the refractive index of walls 408 ′ of enclosure 400 D may be varied by combining two or more different refractive index materials to form the walls of the enclosure.", "FIG. 4E depicts an embodiment of enclosure 400 D′ made of two different materials.", "Enclosure 400 D′ includes walls 408 ″.", "Walls 408 ″ may include two different materials 410 A, 410 B. In certain embodiments, material 410 A has a different refractive index from material 410 B. The different refractive indices of materials 410 A, 410 B may provide a varying refractive index in walls 408 ″ of enclosure 400 D′.", "In certain embodiments, enclosure 400 D′ is formed by coupling, connecting, or attaching together two or more enclosures made of the different materials (e.g., materials 410 A, 410 B) to form the enclosure.", "For example, a first enclosure may include material 410 A and a second enclosure may include material 410 B and enclosure 400 D′ is formed by coupling together the first enclosure and the second enclosure.", "In some embodiments, the enclosures of the different materials are concentric enclosures such as concentric cylindrical enclosures.", "It is to be understood the invention is not limited to particular systems described which may, of course, vary.", "It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.", "As used in this specification, the singular forms “a”, “an”", "and “the”", "include plural referents unless the content clearly indicates otherwise.", "Thus, for example, reference to “a wall”", "includes a combination of two or more walls and reference to “a gas”", "includes mixtures of gases.", "Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description.", "Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention.", "It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments.", "Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention.", "Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims." ]
BACKGROUND OF THE INVENTION The invention relates to an apparatus for cooling and/or warming articles, in particular edible products in the confectionery sector. In many industrial sectors, articles are produced which, following manufacture, have to be cooled or heated. For temperature-control processes of this type there are a large number of apparatuses and methods. In the present case, it is primarily edible products from the confectionery sector whose temperature is to be controlled, that is to say, for example, pralines produced by the one-shot process, which consist of a filling surrounded by a chocolate coating. In this case, what is primarily concerned is that the cooling should be carried out as quickly as possible following manufacture and uniformly from all sides, in order that the edible products maintain their shape. Hitherto, only a few suitable apparatuses have been used for this purpose and are also generally of very complicated construction. It is an object of the present invention to provide an apparatus of the abovementioned type with which the quickest possible temperature control of the articles can be carried out in a simple way, the intention being for the temperature control also to be carried out as far as possible from all sides. SUMMARY OF THE INVENTION The foregoing object is achieved by providing an apparatus for cooling and/or heating articles comprising a housing having a conveyor inlet and a conveyor outlet; at least one cylinder disposed in the housing, the at least one cylinder defining an interior chamber and having at one end thereby provided with one of a air heating means and air cooling means at the other end thereof closure means for closing the cylinder; and a conveyor for passing the articles through the housing and around the at least one cylinder from the conveyor inlet to the conveyor outlet, the conveyor being disposed along a helical path around the at least one cylinder wherein the at least one cylinder is provided with air flow springs feeding air from the interior chamber to the articles. The helical conveyor has the great advantage that it is able to move the products whose temperature is to be controlled continuously past the air openings, so that the articles whose temperature is to be controlled are acted on continuously with cooling or warming air. For this purpose, the obvious thing is for the air openings likewise to be arranged helically in the cylinder, to be specific with a pitch which corresponds approximately to the pitch of the helical conveyor. Added to this is the fact that the air openings are preferably arranged to be offset in relation to one another, so that the products whose temperature is to be controlled are acted on continuously by air, although no continuous slot is formed in the cylinder. In order to produce the cooling or the heating, a cooling or heating element and an appropriate fan should preferably be arranged directly in the cylinder. Of course, both elements could also be located outside the cylinder but the integration of the two elements into the cylinder permits a significantly more compact construction. Although quite good temperature control of the edible products is already carried out with the arrangement of one cylinder and the helical conveyor, in a preferred exemplary embodiment of the invention a first cylinder is to be assigned a second cylinder having corresponding air openings described above. In this case, the helical conveyor is arranged in such a way that it wraps around the second cylinder in the opposite direction to the first cylinder. This means that the helical conveyor rises in the first cylinder and falls in the second cylinder. The significant advantage of the invention resides in the fact that, as a result of reversing the direction of rotation of the helical conveyor, the edible products are acted on by the temperature-control medium from one side in the one cylinder and are acted on from the other side in the other cylinder. The edible products are therefore acted on from all sides with cooling or warming air, so that the temperature control is carried out very uniformly. An essential part of the helical conveyor is a guide track, on which a chain which is connected to a drive runs. The chain is configured in such a way that the edible products whose temperature is to be controlled rest on it and can be transported by it. Should it prove to be expedient, the chain or individual chain links can be covered with appropriate non-slip material. In a preferred exemplary embodiment, the chain comprises a large number of wing-like chain links, which are connected to one another by joints. The joints are configured in such a way that it is made possible for the chain to run around a curve. This means, in a simple exemplary embodiment, that the individual chain links are connected to one another via connecting pins which pass through a double tapered hole in a chain link. This double tapered hole allows the chain links mobility on all sides in relation to one another. In order to save as much height as possible in the individual levels of the helical conveyor, and therefore to be able to construct the entire apparatus with a lower height, it proves to be expedient to arrange the chain with two mutually oppositely rotating horizontal drive gear wheels in each case. These drive gear wheels are arranged, for example, in the guide track itself or pass through the latter and mesh with corresponding bearing points on the chain links, these bearing points preferably having rounded tooth flanks. These bearing points are also assigned guide tabs, which ensure that the drive gear wheels remain meshed with the tooth flanks of the chain links even when running around a curve. A plurality of drive gear wheel pairs of this type are preferably provided over the height of the helical conveyor, in each case arranged level by level. The drive gear wheels of each level are preferably driven by a common drive belt, a drive chain or the like, which is in turn connected to a drive wheel. The drive wheels on one side of a helical conveyor are connected to one another via a drive rod, which is driven by a single motor drive. In addition, the chain runs with its chain links in rail sections of a guide track, which in each case comprises a supporting layer and a sliding layer. Since both the chain links and the guide track are preferably composed of plastic, the sliding layer should be matched to the plastic of the chain links in such a way that as few wear phenomena as possible occur and, on the other hand, it is possible for the chain links to slide without difficulty. For the purpose of guiding the chain links, the guide track has a groove, which is preferably undercut, the joint of the chain link sliding in the undercut. Overall, the groove has a cross section shaped similarly to an inverted T. In order to be able to compensate for production tolerances, thermal expansion and different pitches, the rail sections are preferably not fixed continuously to a machine frame, but only at one end. At the other end, they engage with a tongue in a recess in a following rail section, so that, for example, as a result allowance can be made for thermal expansion in a simple way. Overall, the apparatus is extremely suitable for controlling the temperature of articles and satisfies the abovementioned object without difficulty. In particular, it requires very little maintenance and manages with only a few drives. BRIEF DESCRIPTION OF THE DRAWINGS Further advantages, features and details of the invention emerge from the following description of preferred exemplary embodiments and with reference to the drawing, in which: FIG. 1 shows a schematic side view of an apparatus according to the invention for cooling and/or warming articles; FIG. 2 shows a plan view of the apparatus according to FIG. 1; FIG. 3 shows a partial section through part of the apparatus according to FIG. 1; FIG. 4 shows a perspective illustration of part of a guide track; FIG. 5 shows a plan view of a chain link according to the invention; FIG. 6 shows a side view of the chain link according to FIG. 5; FIG. 7 shows a plan view of parts of the drive for a chain; FIG. 8 shows a plan view of parts of the drive for the apparatus according to FIG. 1 . DETAILED DESCRIPTION An apparatus for cooling and/or warming articles (not specifically shown), such as pallets on which there are edible products from the confectionery sector, has two cylinders 1 and 2 . These cylinders 1 and 2 are composed, for example, of a sheet-metal outer and have air openings 3 , the appropriate air openings being indicated only on the cylinder 2 . However, these openings appear to the same extent on cylinder 1 as well. The air openings 3 are arranged helically and offset in relation to one another, as can be seen in the case of cylinder 2 . The pitch of the helical arrangement corresponds approximately to that of a helical conveyor 4 , which can be seen better in FIG. 2 . This helical conveyor 4 has an inlet 5 and an outlet 6 . Between these, it wraps first around the cylinder 2 in helical paths 7 and 8 , the helical paths 7 rising. After that, it wraps around the cylinder 1 in the opposite direction, the helical paths 8 falling. At the highest point of the helical conveyor 4 there is a straight reversal piece 9 . FIG. 3 shows, in cross section, essentially two tracks 7 / 8 which belong to the helical conveyor 4 and are located one above another. On the inside, a portion of the cylinder 1 / 2 can be seen. On the outside, an outer wall is indicated as part of a machine frame 11 . Between the outer wall and the cylinder 1 / 2 there are supporting arms 12 , on which rail sections 13 of a guide track (not shown specifically) rest. The rail sections 13 are shown in more detail in FIG. 4, but only indicated in part in FIG. 3 . They essentially comprise a sliding layer 14 and a supporting layer 15 in each case. Both are preferably manufactured from plastic, the sliding layer 14 being composed of a plastic which exhibits little wear, but permits chain links (described later) to slide. The sliding layer 14 is divided into two and has a guide slot 16 , in which the chain (described later) is guided. Together with the supporting layer 15 , it forms an undercut groove 17 , the undercut groove 17 having, in cross section, the shape of an inverted T. In FIG. 4, two fastening bolts 18 . 1 and 18 . 2 are used to indicate the fact that the rail section 13 is fixed at one end. Fixing is carried out, for example, to a supporting arm 12 . At the other end, a tongue 19 projects from the end face of the rail section 13 , and, in the position of use, engages in an appropriately shaped recess 20 in the following rail section. This arrangement ensures that not only are fit inaccuracies accommodated, but that it is also possible to make allowance for any thermal expansion. In addition, length differences can be compensated for by smaller or greater pitches. The aforementioned chain 21 comprises a large number of chain links 23 connected to one another via joints 22 (see FIGS. 5 and 6 ). Both sides of the joint 22 are adjoined in each case by a wing 24 . 1 and 24 . 2 . In order to avoid the possibility that supported pallets will slip, in particular in the case of relatively great pitches, each wing 24 . 1 and 24 . 2 can be covered with an anti-slip strip 25 . 1 and 25 . 2 , respectively. It is sufficient for this anti-slip strip 25 . 1 and 25 . 2 to be composed of a somewhat softer plastic. Each joint 22 has a double tapered hole 26 , which is arranged in a projection with which the chain link 23 engages in a recess 27 in a following chain link. This recess 27 is bounded at the sides by two bearing strips 28 . 1 and 28 . 2 , through each of which a hole 29 . 1 and 29 . 2 passes. A bearing pin (not specifically shown) can be placed through the holes 29 . 1 and 29 . 2 and through the double tapered hole 26 , and connects two chain links to each other. The double taper 26 ensures that the chain links 23 can also run around curves. At the sides, approximately parallel to the wings 24 . 1 and 24 . 2 , guide tabs 31 . 1 and 31 . 2 in each case project from the bearing strips 28 . 1 and 28 . 2 . These guide tabs 31 . 1 and 31 . 2 can be seen better in FIG. 7 . They engage over the respective bearing strip 28 . 1 and 28 . 2 , which is illustrated only dashed in FIG. 7 . Each bearing strip 28 . 1 and 28 . 2 forms a rounded tooth flank 32 to be acted on by a tooth 33 of a drive gear wheel 34 . 1 and 34 . 2 , respectively. When the chain is running straight ahead, as shown in FIG. 7, two successive bearing strips 28 . 1 and 28 . 3 have a distance a from each other which is greater than the width b of a tooth 33 . By this means, it is possible for the chain 21 to be taken out of the engagement with the drive gear wheels 34 . 1 and 34 . 2 . When running around a curve, however, the guide tabs 31 . 1 and 31 . 2 engage over the respective teeth 33 which are just acting on the tooth flanks 32 . By this means, it is made impossible for the chain to jump out of its drive. FIG. 8 also shows that the two drive gear wheels 34 . 1 and 34 . 2 are driven only by one drive chain 35 . For this purpose, the drive chain 35 wraps around the drive gear wheels 34 . 1 and 34 . 2 in the manner shown, so that the drive gear wheels 34 . 1 and 34 . 2 can rotate in opposite directions. In addition, the drive chain 35 is further assigned two gear mechanisms or tensioning wheels 36 . 1 and 36 . 2 . The drive is provided via a drive wheel 37 , which is located on the machine frame 11 . It can be seen from FIG. 3 that the drive wheels 37 . 1 and 37 . 2 of one level of the helical conveyor 4 are connected to each other via a drive rod 38 in each case. This drive rod 38 is an output shaft of a motor (not specifically shown). Between the individual drive wheels 37 . 1 and 37 . 2 there are still further bearing points 39 . 1 and 39 . 2 . The functioning of the present invention is as follows: For the purpose of cooling, for example, a pallet with edible products from the confectionery sector is put onto the helical conveyor 4 at the inlet 5 . At the same time, fans 40 and cooling elements 41 in the cylinders 1 and 2 are set operating, as a result of which air is conveyed upward in the interior of the cylinder 1 / 2 . Since each cylinder 1 and 2 is covered at the top, the cooling air escapes from the air openings 3 at the sides and there encounters the pallets, which are moved past the air openings 3 . On the helical track 7 of the cylinder 2 , the pallets are cooled first from one side and, on the helical track 8 of the cylinder 1 , are cooled on the other side. Having been cooled, they pass to the outlet 6 .
A device for cooling and/or heating objects, in particular edible cakes and pastries, has a cylinder into which air is blown and flows out of holes. The cylinder is associated to a spiral conveyor upon which the objects can be carried past their holes.
Briefly describe the main idea outlined in the provided context.
[ "BACKGROUND OF THE INVENTION The invention relates to an apparatus for cooling and/or warming articles, in particular edible products in the confectionery sector.", "In many industrial sectors, articles are produced which, following manufacture, have to be cooled or heated.", "For temperature-control processes of this type there are a large number of apparatuses and methods.", "In the present case, it is primarily edible products from the confectionery sector whose temperature is to be controlled, that is to say, for example, pralines produced by the one-shot process, which consist of a filling surrounded by a chocolate coating.", "In this case, what is primarily concerned is that the cooling should be carried out as quickly as possible following manufacture and uniformly from all sides, in order that the edible products maintain their shape.", "Hitherto, only a few suitable apparatuses have been used for this purpose and are also generally of very complicated construction.", "It is an object of the present invention to provide an apparatus of the abovementioned type with which the quickest possible temperature control of the articles can be carried out in a simple way, the intention being for the temperature control also to be carried out as far as possible from all sides.", "SUMMARY OF THE INVENTION The foregoing object is achieved by providing an apparatus for cooling and/or heating articles comprising a housing having a conveyor inlet and a conveyor outlet;", "at least one cylinder disposed in the housing, the at least one cylinder defining an interior chamber and having at one end thereby provided with one of a air heating means and air cooling means at the other end thereof closure means for closing the cylinder;", "and a conveyor for passing the articles through the housing and around the at least one cylinder from the conveyor inlet to the conveyor outlet, the conveyor being disposed along a helical path around the at least one cylinder wherein the at least one cylinder is provided with air flow springs feeding air from the interior chamber to the articles.", "The helical conveyor has the great advantage that it is able to move the products whose temperature is to be controlled continuously past the air openings, so that the articles whose temperature is to be controlled are acted on continuously with cooling or warming air.", "For this purpose, the obvious thing is for the air openings likewise to be arranged helically in the cylinder, to be specific with a pitch which corresponds approximately to the pitch of the helical conveyor.", "Added to this is the fact that the air openings are preferably arranged to be offset in relation to one another, so that the products whose temperature is to be controlled are acted on continuously by air, although no continuous slot is formed in the cylinder.", "In order to produce the cooling or the heating, a cooling or heating element and an appropriate fan should preferably be arranged directly in the cylinder.", "Of course, both elements could also be located outside the cylinder but the integration of the two elements into the cylinder permits a significantly more compact construction.", "Although quite good temperature control of the edible products is already carried out with the arrangement of one cylinder and the helical conveyor, in a preferred exemplary embodiment of the invention a first cylinder is to be assigned a second cylinder having corresponding air openings described above.", "In this case, the helical conveyor is arranged in such a way that it wraps around the second cylinder in the opposite direction to the first cylinder.", "This means that the helical conveyor rises in the first cylinder and falls in the second cylinder.", "The significant advantage of the invention resides in the fact that, as a result of reversing the direction of rotation of the helical conveyor, the edible products are acted on by the temperature-control medium from one side in the one cylinder and are acted on from the other side in the other cylinder.", "The edible products are therefore acted on from all sides with cooling or warming air, so that the temperature control is carried out very uniformly.", "An essential part of the helical conveyor is a guide track, on which a chain which is connected to a drive runs.", "The chain is configured in such a way that the edible products whose temperature is to be controlled rest on it and can be transported by it.", "Should it prove to be expedient, the chain or individual chain links can be covered with appropriate non-slip material.", "In a preferred exemplary embodiment, the chain comprises a large number of wing-like chain links, which are connected to one another by joints.", "The joints are configured in such a way that it is made possible for the chain to run around a curve.", "This means, in a simple exemplary embodiment, that the individual chain links are connected to one another via connecting pins which pass through a double tapered hole in a chain link.", "This double tapered hole allows the chain links mobility on all sides in relation to one another.", "In order to save as much height as possible in the individual levels of the helical conveyor, and therefore to be able to construct the entire apparatus with a lower height, it proves to be expedient to arrange the chain with two mutually oppositely rotating horizontal drive gear wheels in each case.", "These drive gear wheels are arranged, for example, in the guide track itself or pass through the latter and mesh with corresponding bearing points on the chain links, these bearing points preferably having rounded tooth flanks.", "These bearing points are also assigned guide tabs, which ensure that the drive gear wheels remain meshed with the tooth flanks of the chain links even when running around a curve.", "A plurality of drive gear wheel pairs of this type are preferably provided over the height of the helical conveyor, in each case arranged level by level.", "The drive gear wheels of each level are preferably driven by a common drive belt, a drive chain or the like, which is in turn connected to a drive wheel.", "The drive wheels on one side of a helical conveyor are connected to one another via a drive rod, which is driven by a single motor drive.", "In addition, the chain runs with its chain links in rail sections of a guide track, which in each case comprises a supporting layer and a sliding layer.", "Since both the chain links and the guide track are preferably composed of plastic, the sliding layer should be matched to the plastic of the chain links in such a way that as few wear phenomena as possible occur and, on the other hand, it is possible for the chain links to slide without difficulty.", "For the purpose of guiding the chain links, the guide track has a groove, which is preferably undercut, the joint of the chain link sliding in the undercut.", "Overall, the groove has a cross section shaped similarly to an inverted T. In order to be able to compensate for production tolerances, thermal expansion and different pitches, the rail sections are preferably not fixed continuously to a machine frame, but only at one end.", "At the other end, they engage with a tongue in a recess in a following rail section, so that, for example, as a result allowance can be made for thermal expansion in a simple way.", "Overall, the apparatus is extremely suitable for controlling the temperature of articles and satisfies the abovementioned object without difficulty.", "In particular, it requires very little maintenance and manages with only a few drives.", "BRIEF DESCRIPTION OF THE DRAWINGS Further advantages, features and details of the invention emerge from the following description of preferred exemplary embodiments and with reference to the drawing, in which: FIG. 1 shows a schematic side view of an apparatus according to the invention for cooling and/or warming articles;", "FIG. 2 shows a plan view of the apparatus according to FIG. 1;", "FIG. 3 shows a partial section through part of the apparatus according to FIG. 1;", "FIG. 4 shows a perspective illustration of part of a guide track;", "FIG. 5 shows a plan view of a chain link according to the invention;", "FIG. 6 shows a side view of the chain link according to FIG. 5;", "FIG. 7 shows a plan view of parts of the drive for a chain;", "FIG. 8 shows a plan view of parts of the drive for the apparatus according to FIG. 1 .", "DETAILED DESCRIPTION An apparatus for cooling and/or warming articles (not specifically shown), such as pallets on which there are edible products from the confectionery sector, has two cylinders 1 and 2 .", "These cylinders 1 and 2 are composed, for example, of a sheet-metal outer and have air openings 3 , the appropriate air openings being indicated only on the cylinder 2 .", "However, these openings appear to the same extent on cylinder 1 as well.", "The air openings 3 are arranged helically and offset in relation to one another, as can be seen in the case of cylinder 2 .", "The pitch of the helical arrangement corresponds approximately to that of a helical conveyor 4 , which can be seen better in FIG. 2 .", "This helical conveyor 4 has an inlet 5 and an outlet 6 .", "Between these, it wraps first around the cylinder 2 in helical paths 7 and 8 , the helical paths 7 rising.", "After that, it wraps around the cylinder 1 in the opposite direction, the helical paths 8 falling.", "At the highest point of the helical conveyor 4 there is a straight reversal piece 9 .", "FIG. 3 shows, in cross section, essentially two tracks 7 / 8 which belong to the helical conveyor 4 and are located one above another.", "On the inside, a portion of the cylinder 1 / 2 can be seen.", "On the outside, an outer wall is indicated as part of a machine frame 11 .", "Between the outer wall and the cylinder 1 / 2 there are supporting arms 12 , on which rail sections 13 of a guide track (not shown specifically) rest.", "The rail sections 13 are shown in more detail in FIG. 4, but only indicated in part in FIG. 3 .", "They essentially comprise a sliding layer 14 and a supporting layer 15 in each case.", "Both are preferably manufactured from plastic, the sliding layer 14 being composed of a plastic which exhibits little wear, but permits chain links (described later) to slide.", "The sliding layer 14 is divided into two and has a guide slot 16 , in which the chain (described later) is guided.", "Together with the supporting layer 15 , it forms an undercut groove 17 , the undercut groove 17 having, in cross section, the shape of an inverted T. In FIG. 4, two fastening bolts 18 .", "1 and 18 .", "2 are used to indicate the fact that the rail section 13 is fixed at one end.", "Fixing is carried out, for example, to a supporting arm 12 .", "At the other end, a tongue 19 projects from the end face of the rail section 13 , and, in the position of use, engages in an appropriately shaped recess 20 in the following rail section.", "This arrangement ensures that not only are fit inaccuracies accommodated, but that it is also possible to make allowance for any thermal expansion.", "In addition, length differences can be compensated for by smaller or greater pitches.", "The aforementioned chain 21 comprises a large number of chain links 23 connected to one another via joints 22 (see FIGS. 5 and 6 ).", "Both sides of the joint 22 are adjoined in each case by a wing 24 .", "1 and 24 .", "2 .", "In order to avoid the possibility that supported pallets will slip, in particular in the case of relatively great pitches, each wing 24 .", "1 and 24 .", "2 can be covered with an anti-slip strip 25 .", "1 and 25 .", "2 , respectively.", "It is sufficient for this anti-slip strip 25 .", "1 and 25 .", "2 to be composed of a somewhat softer plastic.", "Each joint 22 has a double tapered hole 26 , which is arranged in a projection with which the chain link 23 engages in a recess 27 in a following chain link.", "This recess 27 is bounded at the sides by two bearing strips 28 .", "1 and 28 .", "2 , through each of which a hole 29 .", "1 and 29 .", "2 passes.", "A bearing pin (not specifically shown) can be placed through the holes 29 .", "1 and 29 .", "2 and through the double tapered hole 26 , and connects two chain links to each other.", "The double taper 26 ensures that the chain links 23 can also run around curves.", "At the sides, approximately parallel to the wings 24 .", "1 and 24 .", "2 , guide tabs 31 .", "1 and 31 .", "2 in each case project from the bearing strips 28 .", "1 and 28 .", "2 .", "These guide tabs 31 .", "1 and 31 .", "2 can be seen better in FIG. 7 .", "They engage over the respective bearing strip 28 .", "1 and 28 .", "2 , which is illustrated only dashed in FIG. 7 .", "Each bearing strip 28 .", "1 and 28 .", "2 forms a rounded tooth flank 32 to be acted on by a tooth 33 of a drive gear wheel 34 .", "1 and 34 .", "2 , respectively.", "When the chain is running straight ahead, as shown in FIG. 7, two successive bearing strips 28 .", "1 and 28 .", "3 have a distance a from each other which is greater than the width b of a tooth 33 .", "By this means, it is possible for the chain 21 to be taken out of the engagement with the drive gear wheels 34 .", "1 and 34 .", "2 .", "When running around a curve, however, the guide tabs 31 .", "1 and 31 .", "2 engage over the respective teeth 33 which are just acting on the tooth flanks 32 .", "By this means, it is made impossible for the chain to jump out of its drive.", "FIG. 8 also shows that the two drive gear wheels 34 .", "1 and 34 .", "2 are driven only by one drive chain 35 .", "For this purpose, the drive chain 35 wraps around the drive gear wheels 34 .", "1 and 34 .", "2 in the manner shown, so that the drive gear wheels 34 .", "1 and 34 .", "2 can rotate in opposite directions.", "In addition, the drive chain 35 is further assigned two gear mechanisms or tensioning wheels 36 .", "1 and 36 .", "2 .", "The drive is provided via a drive wheel 37 , which is located on the machine frame 11 .", "It can be seen from FIG. 3 that the drive wheels 37 .", "1 and 37 .", "2 of one level of the helical conveyor 4 are connected to each other via a drive rod 38 in each case.", "This drive rod 38 is an output shaft of a motor (not specifically shown).", "Between the individual drive wheels 37 .", "1 and 37 .", "2 there are still further bearing points 39 .", "1 and 39 .", "2 .", "The functioning of the present invention is as follows: For the purpose of cooling, for example, a pallet with edible products from the confectionery sector is put onto the helical conveyor 4 at the inlet 5 .", "At the same time, fans 40 and cooling elements 41 in the cylinders 1 and 2 are set operating, as a result of which air is conveyed upward in the interior of the cylinder 1 / 2 .", "Since each cylinder 1 and 2 is covered at the top, the cooling air escapes from the air openings 3 at the sides and there encounters the pallets, which are moved past the air openings 3 .", "On the helical track 7 of the cylinder 2 , the pallets are cooled first from one side and, on the helical track 8 of the cylinder 1 , are cooled on the other side.", "Having been cooled, they pass to the outlet 6 ." ]
BACKGROUND OF THE INVENTION This invention relates to an improved temperature regulating device or thermostat and in particular it relates to a miniature electric thermostat used to regulate or control the temperature of a clothes iron or similar heater systems. Current practice in thermostats of this type is to compose the thermostat of a sandwich of ceramic insulators, metal switch elements and a metal bracket. Ceramics are required for the stability of high temperatures, especially for non-periodic excursions of high temperature sometimes occuring during initial calibration. The construction necessitates many separate pieces and an assembly technique that is difficult to automate. Current practice also is to build into clothes irons or other similar appliances, a separate over-temperature "one shot" type switch to limit the maximum temperature of the appliance. This is a safety feature, and in current practice the temperature control thermostat and over-temperature are two separate controls mounted at different places in the appliance. BRIEF SUMMARY OF THE INVENTION The object of the present invention is to provide an improved assembly which will be more readily manufactured and applied to a clothes iron or the like and will act both to control the temperature of the sole plate of the iron as well as safeguarding against any over heating which is not controlled by the thermostat. The invention comprises an assembly which integrates the temperature control thermostat and the over-temperature switch and is fabricated with an easy-to-assemble "bracket" of organic or plastic material in place of a sandwich, or stack of ceramic insulators, the proposed combination using high temperature plastic for the bracket, but has the advantage that an integral over-temperature switch limits the maximum temperature that the plastic of the bracket would be exposed to, assuring additional stability. The thermostat itself may be a creep or snap type, and the over-temperature switch is preferably a bimetal type, or a "change-of-phase type" such as an eutectic device, or other one shot device. In some applications a manually resettable over-temperature device could be used. DESCRIPTION OF THE DRAWINGS To enable the invention to be fully understood an embodiment thereof will now be described with reference to the accompanying drawings in which; FIG. 1 in side elevation a thermostatic switch according to the invention, FIG. 2 a transverse section to show the general arrangement of the components, FIG. 3 is a plan, and FIG. 4 an elevation showing the switch from the side opposite to that shown in FIG. 1. DESCRIPTION OF THE PREFERRED EMBODIMENTS According to a preferred embodiment as shown in the drawings, the temperature regulating device of the invention comprises a bracket 1 formed of a desired, low-cost, temperature-resisting organic or plastic material. The bracket is mounted by means of a rivet 1a or other conventional means (shown in broken lines in FIG. 2) on a clothes iron 23 having a sole plate 24 (shown in broken lines in FIG. 1). The sole plate is adapted to be heated in conventional manner by a heating element (shown diagrammatically at 25 in FIG. 3) energized from a power source (shown diagrammatically by the line terminal 26 in FIG. 3). The bracket carries a thermally-responsive bimetallic strip 2 so that when the bracket is mounted on the iron, the bimetallic strip directly contacts the sole plate 24 and is adapted to flex in response to change in sole plate temperature. A conventional switch blade 3 is fixed at one end 4 to the bracket 1 and has a central tongue part 3.1. A pin 22 is secured to the bimetallic strip and is adapted to transfer a force representative of the sole plate temperature to the tongue 3.1 as the bimetallic strip flexes. The opposite free end of the switch blade 3 is also in engagement with a temperature adjusting means 5. The temperature adjusting means comprises a shaft 6 which is rotatable in the bracket 1 and which has a cam 7 associated with a cam surface 8 on the bracket so that rotation of the shaft adjusts application of a force to the free end of the switch blade by the screw 14. The shaft 6 is hollow and the screw 14 is rotatably adjustable therein independent of rotation of the shaft 6. A conventional snap action blade 12 which is adapted to be overbalanced by its loading blade 13 in conventional manner is secured at one end to the free end of the switch blade 3 and has its loading blade secured to the tongue 3.1 of the switch blade in conventional manner. A contact 9 is carried on the snap action blade 12 to be engaged and disengaged with a contact 20 carried on another switch blade 21 which is also mounted on the bracket 1. A contact 16 is supported insulatedly on the bracket 1 and a terminal 18 is connected to the contact 16. A terminal 19 is also provided on the switch blade 3. The temperature regulating device of the invention also includes an additional thermally responsive means for protecting the clothes iron or other appliance against occurrence of an over-temperature condition. In the preferred embodiment shown in the drawings, a tail portion 15 on the switch blade 21 is normally biased to move away from the contact 16 but is urged into a closed circuit position engaging the contact 16 by action of a fusible link pin 17 as indicated by the broken line 15a in FIG. 4. The fusible link pin is slidable in the bracket 1 and is adapted to engage the sole plate of the clothes iron when the bracket 1 is mounted on the iron thereby to press the fusible link pin end 17.1 flush with the bottom of the bracket as indicated by the dotted line 17a in FIG. 4, whereby the tail portion 15 of the blade 21 is engaged with the contact 16. The end 17.1 of the fusible link pin engages the sole plate 24 in closely spaced relation to the bimetallic strip 21. The end portion 17.1 of the pin is formed of a metal material or the like having a melting point selected to melt when a predetermined over-temperature condition occurs in the sole plate, that over-temperature level being selected to prevent damage to the organic bracket material when that over-temperature condition occurs. In that arrangement, the contacts 9 and 20 are normally engaged in a closed circuit position as shown in FIG. 2 for energizing the heater element 25 from the power source 26. Rotation of shaft 6 selects the temperature adjusting force applied to switch blade 3 and selects the operating temperature of the iron so that flexing of the bimetallic strip 2 in response to occurrence of the selected operating temperature in the sole plate causes snap-acting movement of the blade 12 to separate contact 9 from contact 20 to deenergize the heater. When the sole plate then cools, bimetallic strip movement reengages the contacts to reenergize the heater. Adjustment of the screw 14 permits calibration of those temperature regulating means. However, when a predetermined over-temperature condition occurs in the sole plate due to a fault condition or the like, the end 17.1 of the fusible link pin melts in prompt response to the over-temperature condition to permit the tail portion 15 of the blade 21 to move away from contact 16 in response to its normal bias to interrupt the heater energy circuit, thereby to protect the organic material of the mounting bracket from damage due to the over-temperature condition. The advantages of this construction are: (1) The clothes iron assembler would only mount, connect and calibrate a single control thermostat bracket over-temperature switch unit; thus eliminating assembly, mounting and connecting a separate over-temperature switch. (2) The thermostat/over-temperature unit would inherently allow the temperature control thermostat and the over-temperature switch to sense the appliance temperature at nearly the same location. This would offer better overall control and simpler calibration of the over-temperature device (current practice is to mount the over-temperature switch in a location remote from the control thermostat). (3) The overall cost would be less for the appliance manufacturer. (4) The plastic bracket on the temperature control thermostat could allow the use of a low cost cam type means for achieving temperature adjustment. Present designs using metal brackets use expensive screw mechanisms for achieving temperature adjustment. The present assembly therefore further reduces the cost. It should be understood that although particular embodiments have been described by way of illustrating the invention, this invention includes all modifications and equivalents of the disclosed embodiments falling within the scope of the appended claims.
A thermally responsive control especially for a clothes iron combines an adjustable, temperature-regulating thermostat and an over-temperature control for limiting maximum temperature levels on a plastic mounting bracket where the over-temperature control also protects the mounting bracket against damage from overheating.
Summarize the patent document, focusing on the invention's functionality and advantages.
[ "BACKGROUND OF THE INVENTION This invention relates to an improved temperature regulating device or thermostat and in particular it relates to a miniature electric thermostat used to regulate or control the temperature of a clothes iron or similar heater systems.", "Current practice in thermostats of this type is to compose the thermostat of a sandwich of ceramic insulators, metal switch elements and a metal bracket.", "Ceramics are required for the stability of high temperatures, especially for non-periodic excursions of high temperature sometimes occuring during initial calibration.", "The construction necessitates many separate pieces and an assembly technique that is difficult to automate.", "Current practice also is to build into clothes irons or other similar appliances, a separate over-temperature "one shot"", "type switch to limit the maximum temperature of the appliance.", "This is a safety feature, and in current practice the temperature control thermostat and over-temperature are two separate controls mounted at different places in the appliance.", "BRIEF SUMMARY OF THE INVENTION The object of the present invention is to provide an improved assembly which will be more readily manufactured and applied to a clothes iron or the like and will act both to control the temperature of the sole plate of the iron as well as safeguarding against any over heating which is not controlled by the thermostat.", "The invention comprises an assembly which integrates the temperature control thermostat and the over-temperature switch and is fabricated with an easy-to-assemble "bracket"", "of organic or plastic material in place of a sandwich, or stack of ceramic insulators, the proposed combination using high temperature plastic for the bracket, but has the advantage that an integral over-temperature switch limits the maximum temperature that the plastic of the bracket would be exposed to, assuring additional stability.", "The thermostat itself may be a creep or snap type, and the over-temperature switch is preferably a bimetal type, or a "change-of-phase type"", "such as an eutectic device, or other one shot device.", "In some applications a manually resettable over-temperature device could be used.", "DESCRIPTION OF THE DRAWINGS To enable the invention to be fully understood an embodiment thereof will now be described with reference to the accompanying drawings in which;", "FIG. 1 in side elevation a thermostatic switch according to the invention, FIG. 2 a transverse section to show the general arrangement of the components, FIG. 3 is a plan, and FIG. 4 an elevation showing the switch from the side opposite to that shown in FIG. 1. DESCRIPTION OF THE PREFERRED EMBODIMENTS According to a preferred embodiment as shown in the drawings, the temperature regulating device of the invention comprises a bracket 1 formed of a desired, low-cost, temperature-resisting organic or plastic material.", "The bracket is mounted by means of a rivet 1a or other conventional means (shown in broken lines in FIG. 2) on a clothes iron 23 having a sole plate 24 (shown in broken lines in FIG. 1).", "The sole plate is adapted to be heated in conventional manner by a heating element (shown diagrammatically at 25 in FIG. 3) energized from a power source (shown diagrammatically by the line terminal 26 in FIG. 3).", "The bracket carries a thermally-responsive bimetallic strip 2 so that when the bracket is mounted on the iron, the bimetallic strip directly contacts the sole plate 24 and is adapted to flex in response to change in sole plate temperature.", "A conventional switch blade 3 is fixed at one end 4 to the bracket 1 and has a central tongue part 3.1.", "A pin 22 is secured to the bimetallic strip and is adapted to transfer a force representative of the sole plate temperature to the tongue 3.1 as the bimetallic strip flexes.", "The opposite free end of the switch blade 3 is also in engagement with a temperature adjusting means 5.", "The temperature adjusting means comprises a shaft 6 which is rotatable in the bracket 1 and which has a cam 7 associated with a cam surface 8 on the bracket so that rotation of the shaft adjusts application of a force to the free end of the switch blade by the screw 14.", "The shaft 6 is hollow and the screw 14 is rotatably adjustable therein independent of rotation of the shaft 6.", "A conventional snap action blade 12 which is adapted to be overbalanced by its loading blade 13 in conventional manner is secured at one end to the free end of the switch blade 3 and has its loading blade secured to the tongue 3.1 of the switch blade in conventional manner.", "A contact 9 is carried on the snap action blade 12 to be engaged and disengaged with a contact 20 carried on another switch blade 21 which is also mounted on the bracket 1.", "A contact 16 is supported insulatedly on the bracket 1 and a terminal 18 is connected to the contact 16.", "A terminal 19 is also provided on the switch blade 3.", "The temperature regulating device of the invention also includes an additional thermally responsive means for protecting the clothes iron or other appliance against occurrence of an over-temperature condition.", "In the preferred embodiment shown in the drawings, a tail portion 15 on the switch blade 21 is normally biased to move away from the contact 16 but is urged into a closed circuit position engaging the contact 16 by action of a fusible link pin 17 as indicated by the broken line 15a in FIG. 4. The fusible link pin is slidable in the bracket 1 and is adapted to engage the sole plate of the clothes iron when the bracket 1 is mounted on the iron thereby to press the fusible link pin end 17.1 flush with the bottom of the bracket as indicated by the dotted line 17a in FIG. 4, whereby the tail portion 15 of the blade 21 is engaged with the contact 16.", "The end 17.1 of the fusible link pin engages the sole plate 24 in closely spaced relation to the bimetallic strip 21.", "The end portion 17.1 of the pin is formed of a metal material or the like having a melting point selected to melt when a predetermined over-temperature condition occurs in the sole plate, that over-temperature level being selected to prevent damage to the organic bracket material when that over-temperature condition occurs.", "In that arrangement, the contacts 9 and 20 are normally engaged in a closed circuit position as shown in FIG. 2 for energizing the heater element 25 from the power source 26.", "Rotation of shaft 6 selects the temperature adjusting force applied to switch blade 3 and selects the operating temperature of the iron so that flexing of the bimetallic strip 2 in response to occurrence of the selected operating temperature in the sole plate causes snap-acting movement of the blade 12 to separate contact 9 from contact 20 to deenergize the heater.", "When the sole plate then cools, bimetallic strip movement reengages the contacts to reenergize the heater.", "Adjustment of the screw 14 permits calibration of those temperature regulating means.", "However, when a predetermined over-temperature condition occurs in the sole plate due to a fault condition or the like, the end 17.1 of the fusible link pin melts in prompt response to the over-temperature condition to permit the tail portion 15 of the blade 21 to move away from contact 16 in response to its normal bias to interrupt the heater energy circuit, thereby to protect the organic material of the mounting bracket from damage due to the over-temperature condition.", "The advantages of this construction are: (1) The clothes iron assembler would only mount, connect and calibrate a single control thermostat bracket over-temperature switch unit;", "thus eliminating assembly, mounting and connecting a separate over-temperature switch.", "(2) The thermostat/over-temperature unit would inherently allow the temperature control thermostat and the over-temperature switch to sense the appliance temperature at nearly the same location.", "This would offer better overall control and simpler calibration of the over-temperature device (current practice is to mount the over-temperature switch in a location remote from the control thermostat).", "(3) The overall cost would be less for the appliance manufacturer.", "(4) The plastic bracket on the temperature control thermostat could allow the use of a low cost cam type means for achieving temperature adjustment.", "Present designs using metal brackets use expensive screw mechanisms for achieving temperature adjustment.", "The present assembly therefore further reduces the cost.", "It should be understood that although particular embodiments have been described by way of illustrating the invention, this invention includes all modifications and equivalents of the disclosed embodiments falling within the scope of the appended claims." ]
FIELD OF THE INVENTION The invention relates to a method for handling core parts for providing a core pack or stack, in which after being removed from a core shooting machine, the core parts are stacked together in a stacker to form a core stack, introduced into a dipping bath and then supplied in particular in positionally correct manner to a casting machine, as well as to an apparatus for handling core parts for providing a ready-to-cast core pack or stack, with a reception means for receiving the cores from a core shooting machine, an adhesion device, a stacker for joining together the core stack and a dipping means. BACKGROUND OF THE INVENTION Cores and moulds for producing castings are formed from individual core parts, which are assembled to form an overall core. For this purpose the individual core parts are individually produced in a core shooting machine and are subsequently assembled by adhesion to form the core stack. Adhesive application and joining together were initially carried out manually. An automatic apparatus in the form of a core stacking machine for the assembly of ready-to-cast core stacks is proposed in DE-OS 35 26 295 including a removal means for discharging the cores from the core shooting machine, a pivoting means for the joint pivoting up of the still separate cores, an adhesive application system, a stacking means for joining together the core stack and a dipping means. For the joint swinging or pivoting of the cores, the pivoting means has a parallel guide, so that the initially horizontally juxtaposed cores, on pivoting in the vertical direction, are super-imposed with their regions to be interconnected. For this purpose the pivoting means has lateral clamping means for the cores, which act on corresponding reception means, which must be constructed on the cores during the manufacture of the cores, for example, hexagonal shoulders. The cores are then kept spaced in the vertical direction. The adhesion means has spray nozzles which can be pivoted between the cores and which can simultaneously be pivoted between the core parts and simultaneously position all the adhesion points. Thus, corresponding adhesion nozzles must be provided for the core part and must be located at a predetermined distance and with a predetermined arrangement on the core part for positioning the adhesion points and which can at the best be adapted by complicated reequipping measures on different types of core parts. After positioning the adhesion points the lifting device engages below the bottom core part and initially raises the same and then, by the bottom core part the other core parts and simultaneously the clamping means release the core parts. The thus formed core stack is pressed together under a certain pressure and subsequently moved to a dipping unit with a dipping tank, where the core stack is placed on a dipping table and immersed with the latter into the dipping liquid. While an apparatus of the aforementioned type operates in a satisfactory manner the proposed apparatus can only process predetermined core parts for predetermined core stacks, unless extensive reequipping and modification measures are taken. In addition, there is a considerable moment of inertia through the pivoting of the spaced core parts, so that high rotary forces must be expended. Finally, the individual core parts are fixed to a relatively marked extent by the clamping means and the reciprocal relative positioning given by the clamping means is maintained even after placing on the lifting means. Thus, as a result of the necessary tolerance during the manufacture of the core parts, the core parts may not be readily assembled and may instead by subject to damage at the fitting points. SUMMARY OF THE INVENTION The aim underlying the present invention resides in providing a method and an apparatus for handling core parts for providing a ready-to-cast core stack which, while avoiding the aforementioned disadvantages encountered in the prior art and providing kinematic improvements, particularly ensuring a secure, reliable assembly of the individual core parts without any damage to the core parts. According to invention, in the case of a method of the aforementioned type, the stacker is exclusively linearly raised in successive manner in each case an upper core part or an already assembled core part stack and that a lower core part is kept floating by an air cushion, while the raised core part or core part stack is placed on the lower core part for assembly. An inventive apparatus solves the problem in that the reception means for the core parts has a pallet for receiving the core parts and that the receptacles have air outlets connected to a compressed air source for producing the air cushion carrying the core parts. As a result of the exclusively linear movement of the initially not yet interconnected individual core parts, the high torques necessary in the prior art are no longer required. This is made possible by the fact that a pallet displaceable on a linear conveyor with individual receptacles for the individual core parts can be used and which merely have to be replaced for adapting to different core parts for the production of core stacks for different objects to be cast, such as different engines. Apart from this possibility of horizontal displaceability, a contribution is particularly made by the air cushion to a problem and complication-free assembly of the individual core parts to form the core stack. The lower core floats on the air cushion and is movable on all sides, so that if a core or already formed core part stack is placed upon from above, the lower core part can adapt with its assembly contours. The variability of the use possibilities is also increased by providing an adhesive spray nozzle movable and pivotable in different directions and which successively controls the individual adhesion points. There are no nozzles provided with rigid relative spacings from the outset and which are only adapted to specific core parts and which require reequipping for dealing with other such parts. According to preferred developments, prior to the dipping into a dipping tank of the core stacks in the stacker, the core stack are initially rotated by at least 90° about a first horizontal rotational axis into a transfer position for a core manipulator and then by 180° about a horizontal axis at right angles to the first horizontal rotational axis over the dipping tank. Prior to the pivoting about the first horizontal rotation axis by 90°, the core stack is rotated about a vertical axis. In addition, in the transfer position, the core stack is rotated about a further axis opposite to the rotation by 90° about the vertical axis. Or prior to the transfer to the carry-away gripper the core stack is rotated by 90° about a vertical axis. Through this movement sequence, as a result of the different movements and movement possibilities, a high adaptability to different types of core parts and core stacks to be produced therefrom is achieved, quite independently from where action has to take place on the corresponding core parts or stacks, in which position they must be dipped in the dipping tank or the dipping bath therein, so that the degassing openings for the core stack are not also dipped into the liquid and also quite independently of where and in which position action takes place on the assembled core stack for conveying away in order to supply it to the casting means. In a preferred development, the inventive apparatus is characterized by vertically movable grippers pivotable about a vertical axis for receiving individual core parts or partly assembled core stacks and/or placing initially raised core parts or partly assembled core stacks on a core part still in its receptacle on the slide and carried by the air cushion. The inventive apparatus is preferably constructed in such a way that the adhesion means has a triaxially movable adhesion head with a pivotable adhesive spray nozzle, so that all the given adhesion points on a core part can be controlled and that the stacker is followed by a core manipulator, which is movable horizontally along a rail to the stacker and is movable by the upper of two gripper arms acting vertically on the core stack between the said arms to the stacker and which is pivotable about a horizontal axis for conveying the core stack to the dipping unit. The invention leads to the assembly of core stacks which are centrifuged after dipping and need only be dried in a further stage for obtaining casting resistance. A fundamental idea of the invention is to provide an apparatus for the assembly of the most varied mould or core stacks for different parts to be cast, such as different engine blocks, particularly if the individual mould or core stacks or individual mould and core parts have to be arranged and aligned differently during assembly and machining. BRIEF DESCRIPTION OF THE DRAWINGS Further advantages and features of the invention can be gathered from the claims and description of embodiments with reference to the attached drawings, wherein: FIG. 1 is a schematic view of a preferred development of the inventive apparatus for handling core parts for providing a ready-to-cast core stack; FIG. 2 a first embodiment of a method for cores for a six-cylinder engine; FIG. 3 a second inventive embodiment of the present invention; FIG. 4 is a further inventive embodiment of the method of the present invention; and FIG. 5 an embodiment of the method according to the present invention for core parts for a four-cylinder engine. DETAILED DESCRIPTION The inventive apparatus is provided for taking over core parts produced in a core shooting machine 1 and which are to be processed to form a ready-to-cast core stack. As shown in FIG. 1 a tool 2 of the core shooting machine 1 holds the core parts 3 after manufacturing of the core parts 3, with the core parts 3 being brought by the tool 2 into the position shown in FIG. 1. For this purpose, the tool 2 of the core shooting machine 1 is optionally rotated about a horizontal axis A. In the position shown in FIG. 1 the core parts 3 are held by the tool 2 above receptacles 4 of a pallet 6 of the apparatus. The pallet 6 is positioned on a slide 7, which is linearly displaceable on a conveyor 8. The receptacles 4 for the core parts 3 have air ducts and outlets 9. The air ducts and outlets 9 can be connected with an air pressure source for the purpose to be explained more fully hereinbelow. A stacker 11 is provided above the conveyor 8, with the stacker 11, including grippers 12 adapted to carry out a substantially horizontal gripping movement and adapted to be pivotable about a vertical axis B. The stacker 11 also has an adhesion means 13 with an adhesion head 14, which is provided with an adhesive spray nozzle 6. The adhesion head 14 can be vertically lowered along the arrow b and can be moved horizontally both in the plate plane and at right angles thereto. The spray nozzle 16 can also be pivoted to all sides, so as to be able reach any point of a core part moved under it and is provided with adhesive at any desired angle and in any direction. A core manipulator 17 is connected to the stacker 11, with the core manipulator 17 including two linearly movable grippers 18, provided with gripping disks 19, pivotable about the axis C. The grippers 18 can be pivoted about a horizontal axis D, arranged symmetrically between the grippers 18 in the illustrated position and about a vertical axis of rotation E. A dipping means 21 is connected to the core manipulator 17 with the dipping means 21 having a dipping tank 22 and a dipping table 23, located on a vertically displaceable arm 24 and adapted to be lowered into the dipping tank 22. The apparatus also has a centrifugal manipulator 26 and a carry-away gripper 27 connected thereto. The core parts 3, individually designated K1, K2, K3 and K4 (FIG. 4), are placed on their corresponding receptacles 4 on the pallet 6 by the lowering of the tool 2 in the direction of the arrow A. For this purpose, the receptacles 4 or the pallet 6 can have holders acting on the core parts 3, when the core parts 3 are merely frictionally held in the tool 2, so as to be able to hold the core parts 3 on the receptacles 4 when the tool 2 is raised again thereby enabling the core parts 3 to be separated from the tool 2. The tool 2 could also be provided with ejectors to eject the core parts 3. Subsequently the slide 7 moves along the conveyor 8 up to the core part K1 below the stacker 11, while the following core part K2 simultaneously passes below the adhesion means 13. The core part K1 is raised by the grippers 12 from the stacker 11. Simultaneously, the spray nozzle 16 provides adhesive to the surface of the core part K2 located below it, namely at the intended points. The slide 7 then moves far enough back to ensure that the core part K2 is positioned below the gripper 12 and then the gripper, with the core part K1, is lowered. Simultaneously, the core part K2 is slightly raised by compressed air supplied through the air ducts and outlets and is maintained in a raised position on a thus formed air cushion, and, optionally, beforehand, the grippers engaging on the core parts 3 are loosened for the removal of the latter/core parts 3. The grippers 12 and the core part K1, held by the grippers 12 are then lowered to such an extent that the core part K1 with its contours formed on the lower surface and adapted to that of the core part K2 engages in accurately fitting manner in core part K2. Through the location of the core part K2 on the air cushion, the core part K2 can be oriented in accordance with the lowered core part K1, without interference by the holding means. This avoids any damage due to interengaging contours of the two core parts as a result of any slight displacement. The grippers 12 are then detached from the core part K1 and are further lowered until reaching a level of the core part K2. The grippers 12 are laterally applied to the core part K2 and raise the core part stack of core parts K1 and K2. The other parts, here K3 and K4, are then provided in the described manner with adhesive and connected to the core part pack to form the final overall core stack 15. In a manner described in DE-OS 35 26 265, when the grippers act on the bottom core part K4, a pressure cylinder with a control device can act on the top of the core stack 15, in order to further compress the core parts 3, in addition to their own weight, so as to ensure a good adhesion action. After producing the overall core stack 15 in the described manner, the core stack 15 is pivoted by the stacker 11 about the vertical axis B by 90°, so that subsequently the upper gripper 18 of the core manipulator 17 passes between the grippers 12 of the stacker 11 and can act together with its lower counterpart on the core stack 15 from both above and below. Following the gripping action of gripper 18, the stack is released by the grippers 12. The core manipulator 17 moves back along a rail 20 out of the area of the stacker 11, pivots the gripper 18 about the axis D and then about the axis E, so that the core stack 15 is held by the gripper 18 in position 15'. Optionally, the disks 19 can be pivoted, if for example, the core stack 15' is to be dipped in the dipping bath pivoted by 180°. The alignment is dependent upon the position of the air ducts and outlets 9 on the core stack 15 or 15' and through which the air in the core stack 15 escapes on casting. These air ducts and outlets 9 must not be dipped into the dipping bath. The core stack 15' is above the dipping tank 22 in a position where it is laterally held by the grippers 18, so that the dipping table 23 is moved against the downwardly directed side and can receive the core stack 15. The grippers 18 release the core stack 15' and pivot the core stack 15' back into the position shown in FIG. 1. By a lifting mechanism the dipping table 18 is immersed so far in the dipping tank 22 and the dipping bath therein such that the core stack 15 is largely immersed in the dipping tank 22, but the air ducts and gas outlets 9 are not immersed, so that no dipping bath liquid can pass through the same into the core stack 15. After adequate immersion, the dipping table 23 is raised until the core stack 15' has again passed out of the dipping tank 22 into its position above the same in FIG. 1. The core stack 15 is here gripped by the centrifugal manipulator 26, which propels around the core stack 15 within a paste protected by trickling or dripping walls or the like, so that the dipping liquid is centrifuged off and drops back into the dipping tank 22. The level of the dipping tank 22 is kept constant by overflows and a pumping mechanism. After centrifuging, the centrifugal manipulator 26 conveys the core stack 15 into position 15", with the core stack 15' being optionally aligned in a desired manner, that is, the core stack 15' is rotated by, for example, 90° into the illustrated position, so that the carry-away grippers 27 laterally engage on the core stack 15' and can then convey the core stack 15' away for intermediate storage or directly for casting. The process sequence is shown in detail in FIGS. 2 to 5 for core parts for producing different engines. FIG. 2 only shows three core parts 3, designated K1 to K3. Prior to placing on the receptacle 4 of the pallet 6, the core parts K1-K3 are pivoted about a horizontal axis by 90° by the tool 2. After placing the core parts K1-K3 on the receptacles 4, the core parts K1-K3 are moved to the left by the pallet 6 and, in this position, the core part K1 is in the vicinity of the stacker 11 (FIG. 1) and the core part K2 below the spray nozzle 16. The core part K1 is then gripped by the grippers 12 of the stacker 11. Unlike in FIG. 1, in the present embodiment, in the viewing direction, one of the grippers 12 is upstream of the core part K1 and a further gripper, downstream thereof. The core stack 15 is then formed in the above-described manner, is taken over by core manipulator 17 and, due to the position of the gripper 12 of the stacker 11, is not previously restricted by the vertical axis B, because the grippers 12 are in a position in which the upper of the grippers 18 can act between them and on the core stack 15. FIG. 2 shows the pivoting of the core stack 15 by the core manipulator 17 about the axis D and the raising of the core stack 15 into the position 15' above the dipping tank 22 by pivoting about the axis E. Dipping takes place in the above-described manner. After removal from the dipping tank 22 the core stack 15 is again pivoted by 180° about the axis F so that it can be conveyed away. In FIG. 3 the sequence is the same as that in FIG. 1 and, in addition to the sequence of FIG. 2 merely has a pivoting of the grippers 12; therefore, the core stack 15 is pivoted about the axis B so that the upper end of the grippers 18 can engage between the grippers 12 for taking over the core stack 15. This is due to the fact that the grippers 12, in FIG. 2, act on the core part K1, etc. in the plate plane and not at right angles, as in FIG. 2. The process sequence of FIG. 4 fundamentally corresponds to that of FIG. 3. Additionally the core stack 15 is pivoted about the vertical axis D by 90° by the disks 19 on the grippers 18 of the core manipulator 17, to ensure that on dipping into the dipping tank 22, the core stack 2 gas outlets 15 air and are directed 9 in and upward direction and are not immersed in the dipping tank 22. This is due to the fact that the individual core parts are here produced in a different position in the core shooting machine than in the case of the core parts for the process sequence of FIG. 3. In the process sequence of FIG. 5 for the core parts of a four cylinder engine, the above-described method step is not put into effect. In addition to the method steps described relative to FIG. 3, prior to transfer to the carry-away grippers 27, the core stack 15 is pivoted again by 90° about a vertical axis by the core manipulator 17, so that the grippers 27 can act in the correct way and convey away the core stack 15". Otherwise the process sequence is as in FIG. 3.
A method and apparatus for improving kinematic characteristics and for obtaining greater variability with respect to the use possibilities when handling core parts for providing a read-to-cast core stack, wherein, following a removal from a core shooting machine, the core parts are assembled at a stacker to form a core stack, introduced into a dipping bath and subsequently supplied in a correct position to a casting machine. The stacker, successively stacks in each case an upper core or an already assembled core part stack, with the upper core part or the already assembled core part stack being exclusively linearly raised and, in each case, a lower core part is held in a floating manner by an air cushion, whereas the raised core part or core part stack is lowered onto the lower core part for assembly.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "FIELD OF THE INVENTION The invention relates to a method for handling core parts for providing a core pack or stack, in which after being removed from a core shooting machine, the core parts are stacked together in a stacker to form a core stack, introduced into a dipping bath and then supplied in particular in positionally correct manner to a casting machine, as well as to an apparatus for handling core parts for providing a ready-to-cast core pack or stack, with a reception means for receiving the cores from a core shooting machine, an adhesion device, a stacker for joining together the core stack and a dipping means.", "BACKGROUND OF THE INVENTION Cores and moulds for producing castings are formed from individual core parts, which are assembled to form an overall core.", "For this purpose the individual core parts are individually produced in a core shooting machine and are subsequently assembled by adhesion to form the core stack.", "Adhesive application and joining together were initially carried out manually.", "An automatic apparatus in the form of a core stacking machine for the assembly of ready-to-cast core stacks is proposed in DE-OS 35 26 295 including a removal means for discharging the cores from the core shooting machine, a pivoting means for the joint pivoting up of the still separate cores, an adhesive application system, a stacking means for joining together the core stack and a dipping means.", "For the joint swinging or pivoting of the cores, the pivoting means has a parallel guide, so that the initially horizontally juxtaposed cores, on pivoting in the vertical direction, are super-imposed with their regions to be interconnected.", "For this purpose the pivoting means has lateral clamping means for the cores, which act on corresponding reception means, which must be constructed on the cores during the manufacture of the cores, for example, hexagonal shoulders.", "The cores are then kept spaced in the vertical direction.", "The adhesion means has spray nozzles which can be pivoted between the cores and which can simultaneously be pivoted between the core parts and simultaneously position all the adhesion points.", "Thus, corresponding adhesion nozzles must be provided for the core part and must be located at a predetermined distance and with a predetermined arrangement on the core part for positioning the adhesion points and which can at the best be adapted by complicated reequipping measures on different types of core parts.", "After positioning the adhesion points the lifting device engages below the bottom core part and initially raises the same and then, by the bottom core part the other core parts and simultaneously the clamping means release the core parts.", "The thus formed core stack is pressed together under a certain pressure and subsequently moved to a dipping unit with a dipping tank, where the core stack is placed on a dipping table and immersed with the latter into the dipping liquid.", "While an apparatus of the aforementioned type operates in a satisfactory manner the proposed apparatus can only process predetermined core parts for predetermined core stacks, unless extensive reequipping and modification measures are taken.", "In addition, there is a considerable moment of inertia through the pivoting of the spaced core parts, so that high rotary forces must be expended.", "Finally, the individual core parts are fixed to a relatively marked extent by the clamping means and the reciprocal relative positioning given by the clamping means is maintained even after placing on the lifting means.", "Thus, as a result of the necessary tolerance during the manufacture of the core parts, the core parts may not be readily assembled and may instead by subject to damage at the fitting points.", "SUMMARY OF THE INVENTION The aim underlying the present invention resides in providing a method and an apparatus for handling core parts for providing a ready-to-cast core stack which, while avoiding the aforementioned disadvantages encountered in the prior art and providing kinematic improvements, particularly ensuring a secure, reliable assembly of the individual core parts without any damage to the core parts.", "According to invention, in the case of a method of the aforementioned type, the stacker is exclusively linearly raised in successive manner in each case an upper core part or an already assembled core part stack and that a lower core part is kept floating by an air cushion, while the raised core part or core part stack is placed on the lower core part for assembly.", "An inventive apparatus solves the problem in that the reception means for the core parts has a pallet for receiving the core parts and that the receptacles have air outlets connected to a compressed air source for producing the air cushion carrying the core parts.", "As a result of the exclusively linear movement of the initially not yet interconnected individual core parts, the high torques necessary in the prior art are no longer required.", "This is made possible by the fact that a pallet displaceable on a linear conveyor with individual receptacles for the individual core parts can be used and which merely have to be replaced for adapting to different core parts for the production of core stacks for different objects to be cast, such as different engines.", "Apart from this possibility of horizontal displaceability, a contribution is particularly made by the air cushion to a problem and complication-free assembly of the individual core parts to form the core stack.", "The lower core floats on the air cushion and is movable on all sides, so that if a core or already formed core part stack is placed upon from above, the lower core part can adapt with its assembly contours.", "The variability of the use possibilities is also increased by providing an adhesive spray nozzle movable and pivotable in different directions and which successively controls the individual adhesion points.", "There are no nozzles provided with rigid relative spacings from the outset and which are only adapted to specific core parts and which require reequipping for dealing with other such parts.", "According to preferred developments, prior to the dipping into a dipping tank of the core stacks in the stacker, the core stack are initially rotated by at least 90° about a first horizontal rotational axis into a transfer position for a core manipulator and then by 180° about a horizontal axis at right angles to the first horizontal rotational axis over the dipping tank.", "Prior to the pivoting about the first horizontal rotation axis by 90°, the core stack is rotated about a vertical axis.", "In addition, in the transfer position, the core stack is rotated about a further axis opposite to the rotation by 90° about the vertical axis.", "Or prior to the transfer to the carry-away gripper the core stack is rotated by 90° about a vertical axis.", "Through this movement sequence, as a result of the different movements and movement possibilities, a high adaptability to different types of core parts and core stacks to be produced therefrom is achieved, quite independently from where action has to take place on the corresponding core parts or stacks, in which position they must be dipped in the dipping tank or the dipping bath therein, so that the degassing openings for the core stack are not also dipped into the liquid and also quite independently of where and in which position action takes place on the assembled core stack for conveying away in order to supply it to the casting means.", "In a preferred development, the inventive apparatus is characterized by vertically movable grippers pivotable about a vertical axis for receiving individual core parts or partly assembled core stacks and/or placing initially raised core parts or partly assembled core stacks on a core part still in its receptacle on the slide and carried by the air cushion.", "The inventive apparatus is preferably constructed in such a way that the adhesion means has a triaxially movable adhesion head with a pivotable adhesive spray nozzle, so that all the given adhesion points on a core part can be controlled and that the stacker is followed by a core manipulator, which is movable horizontally along a rail to the stacker and is movable by the upper of two gripper arms acting vertically on the core stack between the said arms to the stacker and which is pivotable about a horizontal axis for conveying the core stack to the dipping unit.", "The invention leads to the assembly of core stacks which are centrifuged after dipping and need only be dried in a further stage for obtaining casting resistance.", "A fundamental idea of the invention is to provide an apparatus for the assembly of the most varied mould or core stacks for different parts to be cast, such as different engine blocks, particularly if the individual mould or core stacks or individual mould and core parts have to be arranged and aligned differently during assembly and machining.", "BRIEF DESCRIPTION OF THE DRAWINGS Further advantages and features of the invention can be gathered from the claims and description of embodiments with reference to the attached drawings, wherein: FIG. 1 is a schematic view of a preferred development of the inventive apparatus for handling core parts for providing a ready-to-cast core stack;", "FIG. 2 a first embodiment of a method for cores for a six-cylinder engine;", "FIG. 3 a second inventive embodiment of the present invention;", "FIG. 4 is a further inventive embodiment of the method of the present invention;", "and FIG. 5 an embodiment of the method according to the present invention for core parts for a four-cylinder engine.", "DETAILED DESCRIPTION The inventive apparatus is provided for taking over core parts produced in a core shooting machine 1 and which are to be processed to form a ready-to-cast core stack.", "As shown in FIG. 1 a tool 2 of the core shooting machine 1 holds the core parts 3 after manufacturing of the core parts 3, with the core parts 3 being brought by the tool 2 into the position shown in FIG. 1. For this purpose, the tool 2 of the core shooting machine 1 is optionally rotated about a horizontal axis A. In the position shown in FIG. 1 the core parts 3 are held by the tool 2 above receptacles 4 of a pallet 6 of the apparatus.", "The pallet 6 is positioned on a slide 7, which is linearly displaceable on a conveyor 8.", "The receptacles 4 for the core parts 3 have air ducts and outlets 9.", "The air ducts and outlets 9 can be connected with an air pressure source for the purpose to be explained more fully hereinbelow.", "A stacker 11 is provided above the conveyor 8, with the stacker 11, including grippers 12 adapted to carry out a substantially horizontal gripping movement and adapted to be pivotable about a vertical axis B. The stacker 11 also has an adhesion means 13 with an adhesion head 14, which is provided with an adhesive spray nozzle 6.", "The adhesion head 14 can be vertically lowered along the arrow b and can be moved horizontally both in the plate plane and at right angles thereto.", "The spray nozzle 16 can also be pivoted to all sides, so as to be able reach any point of a core part moved under it and is provided with adhesive at any desired angle and in any direction.", "A core manipulator 17 is connected to the stacker 11, with the core manipulator 17 including two linearly movable grippers 18, provided with gripping disks 19, pivotable about the axis C. The grippers 18 can be pivoted about a horizontal axis D, arranged symmetrically between the grippers 18 in the illustrated position and about a vertical axis of rotation E. A dipping means 21 is connected to the core manipulator 17 with the dipping means 21 having a dipping tank 22 and a dipping table 23, located on a vertically displaceable arm 24 and adapted to be lowered into the dipping tank 22.", "The apparatus also has a centrifugal manipulator 26 and a carry-away gripper 27 connected thereto.", "The core parts 3, individually designated K1, K2, K3 and K4 (FIG.", "4), are placed on their corresponding receptacles 4 on the pallet 6 by the lowering of the tool 2 in the direction of the arrow A. For this purpose, the receptacles 4 or the pallet 6 can have holders acting on the core parts 3, when the core parts 3 are merely frictionally held in the tool 2, so as to be able to hold the core parts 3 on the receptacles 4 when the tool 2 is raised again thereby enabling the core parts 3 to be separated from the tool 2.", "The tool 2 could also be provided with ejectors to eject the core parts 3.", "Subsequently the slide 7 moves along the conveyor 8 up to the core part K1 below the stacker 11, while the following core part K2 simultaneously passes below the adhesion means 13.", "The core part K1 is raised by the grippers 12 from the stacker 11.", "Simultaneously, the spray nozzle 16 provides adhesive to the surface of the core part K2 located below it, namely at the intended points.", "The slide 7 then moves far enough back to ensure that the core part K2 is positioned below the gripper 12 and then the gripper, with the core part K1, is lowered.", "Simultaneously, the core part K2 is slightly raised by compressed air supplied through the air ducts and outlets and is maintained in a raised position on a thus formed air cushion, and, optionally, beforehand, the grippers engaging on the core parts 3 are loosened for the removal of the latter/core parts 3.", "The grippers 12 and the core part K1, held by the grippers 12 are then lowered to such an extent that the core part K1 with its contours formed on the lower surface and adapted to that of the core part K2 engages in accurately fitting manner in core part K2.", "Through the location of the core part K2 on the air cushion, the core part K2 can be oriented in accordance with the lowered core part K1, without interference by the holding means.", "This avoids any damage due to interengaging contours of the two core parts as a result of any slight displacement.", "The grippers 12 are then detached from the core part K1 and are further lowered until reaching a level of the core part K2.", "The grippers 12 are laterally applied to the core part K2 and raise the core part stack of core parts K1 and K2.", "The other parts, here K3 and K4, are then provided in the described manner with adhesive and connected to the core part pack to form the final overall core stack 15.", "In a manner described in DE-OS 35 26 265, when the grippers act on the bottom core part K4, a pressure cylinder with a control device can act on the top of the core stack 15, in order to further compress the core parts 3, in addition to their own weight, so as to ensure a good adhesion action.", "After producing the overall core stack 15 in the described manner, the core stack 15 is pivoted by the stacker 11 about the vertical axis B by 90°, so that subsequently the upper gripper 18 of the core manipulator 17 passes between the grippers 12 of the stacker 11 and can act together with its lower counterpart on the core stack 15 from both above and below.", "Following the gripping action of gripper 18, the stack is released by the grippers 12.", "The core manipulator 17 moves back along a rail 20 out of the area of the stacker 11, pivots the gripper 18 about the axis D and then about the axis E, so that the core stack 15 is held by the gripper 18 in position 15'.", "Optionally, the disks 19 can be pivoted, if for example, the core stack 15'", "is to be dipped in the dipping bath pivoted by 180°.", "The alignment is dependent upon the position of the air ducts and outlets 9 on the core stack 15 or 15'", "and through which the air in the core stack 15 escapes on casting.", "These air ducts and outlets 9 must not be dipped into the dipping bath.", "The core stack 15'", "is above the dipping tank 22 in a position where it is laterally held by the grippers 18, so that the dipping table 23 is moved against the downwardly directed side and can receive the core stack 15.", "The grippers 18 release the core stack 15'", "and pivot the core stack 15'", "back into the position shown in FIG. 1. By a lifting mechanism the dipping table 18 is immersed so far in the dipping tank 22 and the dipping bath therein such that the core stack 15 is largely immersed in the dipping tank 22, but the air ducts and gas outlets 9 are not immersed, so that no dipping bath liquid can pass through the same into the core stack 15.", "After adequate immersion, the dipping table 23 is raised until the core stack 15'", "has again passed out of the dipping tank 22 into its position above the same in FIG. 1. The core stack 15 is here gripped by the centrifugal manipulator 26, which propels around the core stack 15 within a paste protected by trickling or dripping walls or the like, so that the dipping liquid is centrifuged off and drops back into the dipping tank 22.", "The level of the dipping tank 22 is kept constant by overflows and a pumping mechanism.", "After centrifuging, the centrifugal manipulator 26 conveys the core stack 15 into position 15", with the core stack 15'", "being optionally aligned in a desired manner, that is, the core stack 15'", "is rotated by, for example, 90° into the illustrated position, so that the carry-away grippers 27 laterally engage on the core stack 15'", "and can then convey the core stack 15'", "away for intermediate storage or directly for casting.", "The process sequence is shown in detail in FIGS. 2 to 5 for core parts for producing different engines.", "FIG. 2 only shows three core parts 3, designated K1 to K3.", "Prior to placing on the receptacle 4 of the pallet 6, the core parts K1-K3 are pivoted about a horizontal axis by 90° by the tool 2.", "After placing the core parts K1-K3 on the receptacles 4, the core parts K1-K3 are moved to the left by the pallet 6 and, in this position, the core part K1 is in the vicinity of the stacker 11 (FIG.", "1) and the core part K2 below the spray nozzle 16.", "The core part K1 is then gripped by the grippers 12 of the stacker 11.", "Unlike in FIG. 1, in the present embodiment, in the viewing direction, one of the grippers 12 is upstream of the core part K1 and a further gripper, downstream thereof.", "The core stack 15 is then formed in the above-described manner, is taken over by core manipulator 17 and, due to the position of the gripper 12 of the stacker 11, is not previously restricted by the vertical axis B, because the grippers 12 are in a position in which the upper of the grippers 18 can act between them and on the core stack 15.", "FIG. 2 shows the pivoting of the core stack 15 by the core manipulator 17 about the axis D and the raising of the core stack 15 into the position 15'", "above the dipping tank 22 by pivoting about the axis E. Dipping takes place in the above-described manner.", "After removal from the dipping tank 22 the core stack 15 is again pivoted by 180° about the axis F so that it can be conveyed away.", "In FIG. 3 the sequence is the same as that in FIG. 1 and, in addition to the sequence of FIG. 2 merely has a pivoting of the grippers 12;", "therefore, the core stack 15 is pivoted about the axis B so that the upper end of the grippers 18 can engage between the grippers 12 for taking over the core stack 15.", "This is due to the fact that the grippers 12, in FIG. 2, act on the core part K1, etc.", "in the plate plane and not at right angles, as in FIG. 2. The process sequence of FIG. 4 fundamentally corresponds to that of FIG. 3. Additionally the core stack 15 is pivoted about the vertical axis D by 90° by the disks 19 on the grippers 18 of the core manipulator 17, to ensure that on dipping into the dipping tank 22, the core stack 2 gas outlets 15 air and are directed 9 in and upward direction and are not immersed in the dipping tank 22.", "This is due to the fact that the individual core parts are here produced in a different position in the core shooting machine than in the case of the core parts for the process sequence of FIG. 3. In the process sequence of FIG. 5 for the core parts of a four cylinder engine, the above-described method step is not put into effect.", "In addition to the method steps described relative to FIG. 3, prior to transfer to the carry-away grippers 27, the core stack 15 is pivoted again by 90° about a vertical axis by the core manipulator 17, so that the grippers 27 can act in the correct way and convey away the core stack 15".", "Otherwise the process sequence is as in FIG. 3." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention pertains to a humanoid detector and a method of detecting a humanoid within a surveillance area using the humanoid detector. 2. Description of the Related Art Human body detection apparatuses detect humanoid intruders in a surveillance area. The surveillance area is an area of interest that is being surveyed to detect intruders. Human body detection apparatuses may also be useful in combination with air conditioning, or lighting, control apparatuses that automatically control air conditioning, or lighting, according to whether or not a human being is present in an area. A first type of human body detection apparatus is a pyroelectric infrared sensor that detects a human body by detecting a temperature change in a field of view. This type of sensor relies upon a fact that a human body temperature is higher than an ambient temperature. Thus, when a high-temperature object (i.e., the object's internal temperature is greater than ambient temperature) enters a field of view of a pyroelectric infrared sensor, the object radiates infrared rays that are incident on the pyroelectric infrared sensor causing the sensor to generate a voltage. A human body detection apparatus containing such a pyroelectric infrared sensor is preset with a threshold voltage for deciding whether or not an object which enters the field of view is a human body. That is, when the voltage generated by the pyroelectric infrared sensor exceeds the threshold voltage, the object is presumed to be a human body. The pyroelectric infrared sensor in a conventional human body detection apparatus is an infrared point sensor, and it cannot generate an infrared image. Therefore, a conventional human body detection apparatus that exclusively uses a pyroelectric infrared sensor cannot determine a size of an object that is radiating the infrared rays. Further, a human detection apparatus that exclusively uses a pyroelectric infrared sensor often cannot distinguish between incident infrared rays radiated by a human body versus those radiated by a small animal. Accordingly, such sensors have the problem of erroneously detecting small animals as human intruders. A second type of prior art human body detection apparatus uses a pyroelectric infrared image sensor. Such infrared image sensors can reduce the aforesaid erroneous detection of small animals as humanoid intruders by detecting the size of the subject based on the infrared image. However, a pyroelectric infrared image sensor is expensive as compared to an infrared point sensor. Also, a lens for an infrared image sensor is very expensive as compared to a lens for a visible light image sensor. Accordingly, the cost of a human body detector that contains a pyroelectric infrared image sensor is more expensive than other types of human body detectors. Also, miniaturizing a human body detection apparatus that contains a pyroelectric infrared image sensor is more difficult than with other detectors, such as those using infrared point sensors or visible light image sensors. A third type of human body detection apparatus contains a visible light image sensor that detects a moving body by comparing a continuously generated image. Upon detection of the moving body, this type of detection apparatus determines a size of the detected body and, if the body complies with predetermined parameters, decides that the body is humanoid. However, this type of human body detection apparatus can produce erroneous results when any large-body motion is detected, such as a curtain that is swayed by the wind. There are monitoring devices that have a pyroelectric infrared sensor for sensing infrared radiation to detect intruders and a visible light image sensor for recording image data of the surveillance area when a temperature difference is detected by the infrared sensor. But these monitoring devices merely record the image generated by the imaging element and do not use image information to electronically decide whether the body that caused the infrared radiation is humanoid. Thus, image recording occurs even if a small animal intrudes into the surveillance area, so long as the animal is large enough to trigger the infrared sensor's threshold setting. SUMMARY OF THE INVENTION The present invention solves the above-noted deficiencies of the prior art by providing a high-performance human body detector that is relatively inexpensive and more accurate than prior art detection apparatuses that rely on pyroelectric infrared image sensors and that is relatively more accurate and reliable than prior art detection apparatuses that rely on pyroelectric infrared point sensors or visible light image sensors. The human body detector of the present invention includes a moving body detection sensor that detects a moving body using a visible light image in combination with an infrared sensor. In preferred embodiments, the visible light sensor provides a signal to a human body detection circuit. The human body detection circuit then analyzes the size of the detected moving body and decides whether the moving body is of a size substantially equivalent to a human body size. The human body detection circuit also analyzes the infrared radiation detected by the infrared sensor to determine if the detected infrared radiation is substantially equivalent to infrared radiation of a human body. If the detection circuit determines that the size of the moving body is substantially human-size and the detected infrared radiation is above a threshold value, then the detection circuit decides that the intruder is human. Accordingly, the human body detector of the present invention reliably reduces erroneous detection as compared to a human body detection apparatus of the prior art that includes only a moving body detection sensor or only an infrared sensor. Also, the infrared sensor of the present invention need not generate an infrared image. Thus, the present invention may incorporate an infrared image sensor having very few pixels that does not generate an infrared image (for example, an infrared image sensor consisting of only four pixels in a 2×2 matrix). Such infrared image sensors are relatively inexpensive as compared to infrared image sensors that have a large plurality of pixels, which are required to generate an infrared image. Thus, the human body detector of the present invention can achieve low cost and small size as compared to a human body detection apparatus provided with an infrared image sensor that generates an infrared image. Preferably, the moving body detection sensor of the present invention is a visible light image sensor that detects a moving body by repeatedly imaging a field of view (i.e., a surveillance area). The moving body sensor generates a stream of sequential electrical signals corresponding to incident light on the sensor and compares those successive electrical signals and generates a difference signal that indicates whether or not a change occurred within the field of view. Also, in preferred embodiments, the human body detector of the present invention is arranged so that the infrared sensor and visible light image sensor share at least part of the same field of view. In preferred embodiments, the human body detection apparatus of the present invention is further characterized in that the human body detection circuit decides that the moving body is a human body if a level of infrared radiation, or a change in the level of infrared radiation, that is detected by the infrared sensor reaches or exceeds a predetermined value during a predetermined time interval after the size of the moving body reaches or exceeds a predetermined size. Alternatively, the human body detection circuit may decide that the subject is humanoid if the size of the subject exceeds a predetermined size during a particular time interval after the infrared level, or change in the infrared level, detected by the infrared sensor reaches or exceeds a predetermined value. Generally the time until a moving body detection sensor detects a moving body is different from the time until an infrared sensor detects the predetermined infrared level, or the change in the infrared level. Also, there may be instances in which the level of infrared radiation, or the change in the level of infrared radiation, reaches or exceeds the predetermined value because a part of a human being with a high temperature, such as an uncovered face or hands, enters the infrared sensor's field of view, but the size of the moving body does not reach or exceed the predetermined size because only a small portion of the human body has entered the field of view. Therefore, the first moment of confirmation that the size of a moving body has reached or exceeded the predetermined size and the first moment of confirmation that the infrared level, or the change in the infrared level, has reached or exceeded the predetermined value do not always coincide, and a time lag between detection signals can occur. The human body detector of the present invention can eliminate errors due to this sort of time lag by holding the respective signals at a high level (indicating that the size has reached the predetermined size, or the infrared radiation level has reached the predetermined value) for a preselected time interval. Preferably, the human body detector of the present invention uses a pyroelectric infrared sensor. Human body detectors are often installed in difficult access locations, such as high places, where replacement is not easy. Therefore, a pyroelectric infrared sensor, which has better durability than a cooled-type infrared sensor whose life is limited by the cooling device, is desirable. A pyroelectric infrared sensor is also preferred because it provides a signal indicating an amount of change only when the level of infrared radiation changes. Thus, such a sensor is more suitable for a human body detection apparatus than an infrared sensor which detects the absolute level of infrared radiation. The human body detector of the present invention may further include an alarm generation circuit that generates an alarm if the decision circuit decides that the moving body is a human being. Alternatively, the present invention may include other intrusion indicators that are triggered when the decision circuit decides that a moving body in the field of view is a human body. In preferred embodiments, the human body detection method of the present invention detects a moving body using a visible light image to measure a size of the moving body and an infrared sensor to detect an infrared radiation level, or a change in the infrared radiation level, within a field of view. The method further includes comparing the size of the moving body to a predetermined body size and comparing the amount, or change in the amount, of infrared radiation to a predetermined value to determine that the subject body is humanoid. Such combination of body size and infrared radiation in a surveillance field, provides a unique method of providing a reliable indication of a humanoid presence in the surveillance field. The human body detection method of the present invention reduces erroneous detection as compared to prior art human body detection methods which only detect the size of a moving body, or the amount of infrared rays or the amount of change in infrared rays. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic drawing of a preferred embodiment of the present invention showing a humanoid detector receiving incident light and infrared rays from an exemplary surveillance area. FIG. 2 is a schematic circuit diagram showing a general structure of a visible light image sensor of the present invention. FIG. 3 is a timing diagram showing the signal traces generated in the process of detecting an intruder. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention are described with reference to FIGS. 1-3. In FIG. 1, an intruder detection apparatus 1 is provided with detection head 2, infrared sensor read circuit 3, image sensor read circuit 4, decision circuit 5, and alarm generation circuit 6. Detection head 2 includes an infrared sensor 10 (preferably, a pyroelectric infrared point sensor), infrared lens 11 30 disposed in front of the infrared sensor 10, visible light image sensor 12 (preferably, a visible light image sensor for moving body detection), and visible light lens 13 disposed in front of the visible light image sensor 12. Infrared sensor 10 is connected to infrared sensor read circuit 3 via a cable 21. Similarly, visible light image sensor 12 is connected to the image sensor read circuit 4 via a cable 22. Infrared sensor read circuit 3 is connected to decision circuit 5 via a cable 23, and image sensor read circuit 4 is connected to decision circuit 5 via a cable 24. Decision circuit 5 is connected to alarm generation circuit 6 via a cable 25. Furthermore, detection head 2 is situated at a location where it can receive infrared rays 31 and visible light 32 generated from a subject 30 located within a monitoring, or surveillance, area (not numbered). In FIG. 1, the subject 30 is represented as a humanoid. The positions of the infrared sensor 10 and visible light image sensor 12 are arranged so that their field of view is shared and encompasses the detection area. FIG. 2 is a schematic circuit diagram showing a preferred embodiment of the visible light image sensor 12. In FIG. 2, a plurality of pixels 100 is disposed in a matrix. (For clarity, the plurality of pixels is shown as four pixels arranged in a 2×2 matrix. Preferred embodiments of the visible light image sensor would comprise many more pixels.) A vertical read line 102 is provided for each column of pixels 100 and is shown aligned in the vertical direction. The vertical read lines 102 are connected to respective transistors QX in pixel 100 and respective difference detection circuits 104. Each pixel 100 includes a photodiode PD that generates an electric charge corresponding to incident light. A junction-type field effect transistor QA, which outputs an electric signal equivalent to the charge generated by photodiode PD when in communication with the photodiode PD via switching MOS transistor QT. Transistor QT connects or isolates photodiode PD and transistor QA in response to signals φTGm (where "m" is a row number corresponding to the position of a pixel being read) from a vertical scan circuit 106. A reset transistor QP discharges charges that accumulate in a gate region of transistor QA. Switching MOS transistor QX connects or isolates vertical read line 102 and transistor QA. The respective difference detection circuits 104 comprise switching MOS transistors QR and QS, capacitors CR and CS, which store charges corresponding to the electrical signals output at a different times from pixel 100. The difference detection circuits 104 also include a comparison circuit XA, which compares the charges stored in capacitors CR and CS as described in detail below. FIG. 3 is a timing diagram showing signals that are generated in the course of detecting an intruder. Next, the operation of this embodiment is explained with reference to the figures. Preferably, infrared sensor 10 is a pyroelectric infrared point sensor. The sensor supplies infrared sensor read circuit 3 with an electrical signal corresponding to changes in the level of infrared radiation that passes through infrared lens 11 and are incident on the sensor. Infrared sensor read circuit 3 decides whether or not the electrical signal supplied from infrared sensor 10 has reached or exceeded a predetermined value, and generates a binary signal indicating its decision result (hereinafter "infrared signal"), and supplies it to the decision circuit 5. A comparator is suitable as the infrared sensor read circuit 3. The comparator compares a signal from the infrared sensor to a predetermined value stored in the comparator and provides the infrared signal that indicates whether the infrared sensor signal is bigger than the predetermined value. Furthermore, in FIG. 3, at timing trace (a), the periods t1-t2 and t7-t8 in which the infrared signal is at a high level, indicate a state in which the electrical signal supplied from infrared sensor 10 has reached or exceeded the predetermined value. That is, during these periods the sensor has detected a subject in the surveillance area (e.g., humanoid or small animal) with a temperature (infrared radiation) that is higher than the surroundings. Meanwhile, visible light image sensor 12 detects a difference between two consecutive frames at the pixel unit, and supplies image sensor read circuit 4 with a binary signal indicating whether or not the difference has reached or exceeded a predetermined value (hereinafter "difference signal"), and correlates it with each pixel. Here the process of generating a difference signal by visible light image sensor 12 shall be explained. First, at visible light image sensor 12 the optical image obtained from visible light lens 13 is focused on the photoelectric conversion face, where it is photoelectrically converted by photodiode PD in each pixel 100. Timing signals provided by the vertical scan circuit 106 control a transfer of signals from photodiode PD. The signal charge generated by photodiode PD by this sort of photoelectric conversion is transferred to the gate of transistor QA when transistor QT in pixel 100 is made conductive by timing signal φTG2 (in the case of pixel 100 located at row 2). If transistor QT is subsequently made nonconductive, transistor QA's gate region becomes floating, and the aforesaid signal charge from PD is held by a parasitic capacitance effect. That is, transistor QA's gate region stores the signal charge generated by photodiode PD and temporarily holds it. For lexicographic reasons, a definition of "previous frame" and "current frame" is provided. A "frame" is a set of signals from the plurality of pixels that are read in sequence. In the preferred embodiment of FIG. 2, signals corresponding to one row of pixels 100 are simultaneously transferred to vertical read lines 102 and transferred to difference detection circuits 104. Then the next row of pixels in the scanning sequence is read by transferring that row of pixel signals to the vertical read lines 102. After all the rows in the sequence have been read, a frame is complete. A subsequent frame is then read by repeating the sequence of reading the pixels row-by-row. After an initial frame is read (e.g., the first signal after starting the system), a legacy signal, or charge, from a previous frame remains on a gate region of the transistor QA until a current frame is to be read. Accordingly, the terms "previous frame" and "current frame" refer to frames of pixels read in sequence. Thus, in the following description a signal charge for the previous frame is already stored in transistor QA's gate region and a signal charge for a current frame is newly generated by photodiode PD and is transferred to QA after the previous frame's signal is transferred to capacitor CR, as described below. In this state, transistor QX in pixel 100 and transistor QR in difference detection circuit 104 are made conductive and a source follower effect operates on transistor QA, and the charge corresponding to the signal charge for the immediately previous frame stored in transistor QA's gate region charges capacitor CR in difference detection circuit 104 via vertical read line 102. Transistor QP in pixel 100 is made conductive and the signal charge stored in transistor QA's gate region is discharged and initialized. Then, transistor QT in pixel 100 is made conductive and the signal charge for the current frame newly generated by photodiode PD is transferred to transistor QA. Transistor QX in pixel 100 and transistor QS in difference detection circuit 104 are made conductive and a source follower effect operates on transistor QA, and the signal charge for the current frame transferred to transistor QA's gate charges capacitor CS in difference detection circuit 104 via vertical read line 102. That is, the charge corresponding to the signal charge for the immediately previous frame is stored in capacitor CR in difference detection circuit 104, and the charge corresponding to the signal charge for the current frame is stored in capacitor CS. Also, the signal charge for the current frame transferred to pixel 100's transistor QA gate is held in transistor QA's gate region, and in the next frame is used as the signal charge for the previous frame. Comparison circuit XA obtains an absolute value for the difference between the signal voltages corresponding to the charges on capacitors CR and CS, which represent the incident light on photodiode PD in previous and current frames, respectively. Thus, if CR and CS are different, a change in luminescence has occurred in the surveillance area. Comparison circuit XA compares the voltages on capacitors CR and CS and outputs a binary signal indicating "1" (a signal level indicating that change occurred) if the absolute value reaches or exceeds a predetermined value. Conversely, comparison circuit XA outputs a signal indicating "0" (a signal level indicating that change has not occurred) if the absolute value is less than the predetermined value. The signal output from comparison circuit XA in this manner (equivalent to a difference signal) is sequentially output from the image sensor 12 via a horizontal scanning circuit 108. In this manner the difference signal output from visible light image sensor 12 is supplied to image sensor read circuit 4 via cable 22. Based on the difference signal supplied from visible light image sensor 12, image sensor read circuit 4 calculates the number of pixels in a region that includes the portion where change occurred (hereinafter "number of moving body pixels"), and calculates a size of the moving body according to the number of moving body pixels and an optical magnification and a distance from the detection head 2 to the subject 30. And, based on the moving body size thus calculated, the image sensor read circuit 4 decides whether or not the moving body is approximately the size of a human body and generates a binary signal that indicates the decision result (hereinafter "moving body signal") and supplies the moving body signal to the decision circuit 5. For example, in a situation in which a 400,000 pixel image sensor is used as the visible light image sensor 12 and the optical magnification and distance from detection head 2 to the subject are set so that the detection area is three square meters, the area equivalent to one pixel is 0.225 cm 2 . If one assumes that the approximate size of a human body is 150×40 cm and that the size of a small animal is approximately 10×5 cm, then the size of a human body is equivalent to about 27,000 pixels and the size of a small animal is equivalent to about 200 pixels. Therefore, the image sensor read circuit 4 should decide that a moving body within the detection area is about the size of a human body if the number of moving body pixels exceeds 2,000, or so, pixels. Incidentally, in FIG. 3, at timing trace (c), the periods during which the moving body signal is at a high level (i.e., t4-t5 and t9-t10) indicate that a moving body about the same size as a human body is present in the detection area. Based on the infrared signal supplied from the infrared sensor read circuit 3 and the moving body signal supplied from the image sensor read circuit 4, detection circuit 5 decides whether or not an intruder (equivalent to a moving human body) is present, and generates a signal indicating that decision result (hereinafter "decision signal"). The process of generating a decision signal by decision circuit 5 is described. First, when the infrared signal supplied from infrared sensor read circuit 3 is at a high level, thus indicating that a subject having a greater infrared radiation as compared to the surroundings has entered the detection area, decision circuit 5 holds the infrared signal in a high level state for a predetermined period of time (the periods equivalent to t1-t3 and t7-t11 in FIG. 3). Also, when the moving body signal supplied from the image sensor read circuit 4 is at a high level, thus indicating that a moving body about the same size as a human body is present in the detection area, the decision circuit 5 holds the moving body signal in a high level state for a predetermined period of time (the periods t4-t6 and t9-t12 in FIG. 3). When the infrared signal after holding (shown as trace (b) in FIG. 3) and the moving body signal after holding (trace (d) in FIG. 3) are both at a high level (time interval t9-t11 in FIG. 3), the decision circuit 5 generates a high level signal (indicating that an intruder is present) as the decision signal. That is, the interval during which the infrared signal and the moving body signal both go high, as in time intervals t9-t11 in FIG. 3, the decision signal is made high to indicate that a human being has intruded into the detection area. At the moment that the decision signal generated by decision circuit goes high, alarm generation circuit 6 may be arranged to generate an alarm indicating that an intruder has been detected. Furthermore, the interval during which an alarm is generated is not limited to the interval during which the decision signal is at a high level. For example, this period may be from the moment the decision signal temporarily goes high until an alarm stop switch (not shown in drawings) is operated. Alternatively, the decision signal may also be used to operated other systems such as video recording devices or video monitors. As stated, in preferred embodiments, the infrared signal and moving body signal are held for a predetermined time interval. In a preferred embodiment, the visible light image sensor 12 generates a difference signal every 1/30th of a second (approximately once every 33ms), whereas the hold period for the infrared sensor 10 is about 100 ms. Therefore, there is little possibility of the infrared signal (FIG. 3, trace (a)) and the moving body signal (FIG. 3, trace (c)) both going high simultaneously unless the signals are held high for a predetermined time interval after they are triggered high by detection of infrared rays or image size, respectively. Also, there can be instances in which the amount of change in infrared rays exceeds the predetermined value because some portion of a human being such as a face or hands, which are typically exposed and thus have higher infrared radiation as compared to clothed body portions, enters the field of view of the infrared sensor 10, but the size of the detected moving body (face or hands) does not yet exceed the predetermined size. When more of the subject body enters the field of view, the change in infrared radiation may be below the predetermined value, but the subject image size is now greater than its respective predetermined value. However, because both signals are not exceeding their respective predetermined values, the decision signal remains low indicating no intruder. This situation could lead to a failure to detect an intruder. Thus, occurrences of the aforesaid detection failures can be reduced by holding the infrared signal and the moving body signal high for a predetermined time interval after they are triggered high by detection of infrared rays (amount or change in amount) and image size, respectively. However, erroneous detection may also occur if the hold period is too long. A preferred hold period is approximately a few seconds. The decision signal is at a low level, indicating no intruder, in the period during which only the infrared signal is high (FIG. 3, time intervals t1-t3) and in the period during which only the moving body signal is high (FIG. 3, time intervals t4-t6). Thus, an intruder indication does not occur, or is unlikely, when the subject detected is a small animal or a moving body whose temperature is about the same as its surroundings (for example, a swaying curtain). The intruder detector of the present invention permits the respective fields of view of the infrared sensor 10 and the visible light image sensor 12 to be arranged so as to include all of the detection/surveillance area, so that intruders can be detected with good accuracy. The intruder detector of the present invention includes the visible light image sensor 12 for generating the difference signal. Thus, the detector of the present invention does not need peripheral circuits such as an A/D conversion circuit, image memory, and image processing circuit that are mandatory in the case of many prior art detection apparatuses that are equipped with a visible light image sensor for generating simple image data. The embodiments describe above include a pyroelectric infrared point sensor for detecting infrared radiation amounts or changes. However, an inexpensive infrared image sensor having few pixels, (for example, four pixels in a 2×2 matrix) is also suitable for detecting subjects that have a temperature that is higher than its surroundings. Also, this embodiment decides the size of a moving body using the number of moving body pixels, but other methods may be suitable to decide the size of the moving body. For example, a method that uses the number of pixels that change or a method that extracts the edge portion of the moving body by analyzing difference signals. Other methods are also suitable. In addition, in this embodiment infrared sensor 10 and visible light image sensor 12 have a common field of view and their position is adjusted in advance to include all of the detection area. But, for example, when the infrared sensor field of view and the visible light image sensor field of view are narrower than the detection area, it is possible to detect an object having a higher temperature than its surroundings within the detection area using a plurality of infrared sensors with different fields of view, and combine the field of view of a visible light image sensor with the field of view of an infrared sensor which detected an object having a higher temperature than the surroundings. In other alternative embodiments, a difference signal may be generated by comparison of images. For example, the output of a visible light image sensor that generates simple image data may be converted by an A/D converter, and the image data for two consecutive frames may be stored in an image memory. Then the difference between two consecutive frames at the pixel unit may be detected using the digital image data held in the image memory, thereby generating a difference signal. In alternative embodiments, the fields of view of the infrared sensor 10 and the visible light image sensor 12 are not identical or overlapping. For example, if the field of view of the infrared sensor 10 and the field of view of the visible light image sensor 12 are adjacent and the separation between each sensor's field of view is small, the system may decide whether or not the conditions of a high infrared radiation subject and a humanoid sized subject are the same subject by adjusting the time period during which the infrared signal is held at a high level or the time period during which the moving body signal is held at a high level, or both. In another alternative embodiment, the detection of an object of higher temperature than its surroundings may be detected by using a thermal-type infrared sensor such as a pyrometer. In addition, the intruder detector of the present invention generates a difference signal based on a visible light optical image. Thus, preferred embodiments are suitable for detecting an intruder during the day. However, alternative embodiments of the invention can detect an intruder at night by illuminating the detection area with near-infrared light (for example, near 800 nm), to which visible light image sensor 12 is sensitive. In the above-described embodiments, the image sensor read circuit 4, decision circuit 5, and alarm generation circuit 6 are portrayed as discrete circuits. Alternatively, the image sensor drive circuit 4, decision circuit 5, and alarm generation circuit 6 may be fabricated as integrated circuits. Furthermore, because of miniaturization in semiconductor chip technology, preferably these circuits are fabricated on a single integrated circuit. The present invention encourages miniaturization and cost reduction by making it possible to detect a moving body using a simple circuit structure without providing peripheral circuits such as an A/D conversion circuit, image memory, and image processing circuits. Thus, this invention makes it possible to reduce erroneous detection as compared to an intruder detection apparatus equipped with a visible light image sensor or pyroelectric-type infrared point sensor alone. Further, this invention can maintain a low cost as compared to an intruder detection apparatus equipped with an infrared image sensor. Furthermore, the present invention eliminates the time lag between the first moment of confirmation that the size of a moving body has reached or exceeded the specified size and the first moment of confirmation that the amount of infrared rays or the amount of change in infrared rays within the detection area due to the moving body has reached or exceeded the specified value. This method thus reduces detection failures. In the image sensor of the present invention, the difference detection circuit 104 compares pixel signals of current and previous frames. As described, the pixel signals are successive signals, that are time sequenced pixel signals that are provided to the difference detection circuit one after another. However, other sequences are also suitable and may be employed to reduce the size of the image signal (not the size of the detected image) or increase the system speed. Thus, a current frame pixel signal may be compared to a pixel signal from several frames earlier. This may be less accurate, but may nonetheless be suitable in some applications. This specification sets forth the best mode for carrying out the invention as known at the time of filing the patent application and provides sufficient information to enable a person skilled in the art to make and use the invention. The specification further describes preferred materials, shapes, configurations and arrangements of parts for making a using the invention. However, other such materials, shapes, configurations, and arrangements may by used and it is intended that the scope of the invention shall only be limited by the language of the claims and the law of the land as pertains to valid U.S. patents.
A humanoid detector for detecting a humanoid in a surveillance area that substantially reduces false intruder indications by having two types of sensors that provide two types of information of the surveillance area, is disclosed. A first sensor detects light images and determines a size of a moving object within the surveillance area and compares the size of detected moving objects to a threshold size to reduce intruder detection caused by small animals. A second sensor detects infrared radiation from the surveillance area provides a detected infrared radiation signal. A decision circuit receives the sensor signals and provides a decision signal that indicates a human intruder in the surveillance area when, simultaneously, the size of the moving body is greater than that of a small animal and the detected infrared radiation indicates that the moving body is a heat producing body. In order to compensate for differences in the sensors and to account for different physical properties in the surveillance area, the decision circuit holds high an intruder signal for a predetermined time from each sensor. Thus, if a signal occurs that indicates a moving body is larger than a small animal, that signal is held for a predetermined time interval and if a signal indicates a sufficient increase in the infrared radiation occurs while the moving body signal is being held, then the decision circuit determines that a human intruder has entered the surveillance area. The decision signal may be used to trigger an audible or visible indication.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention pertains to a humanoid detector and a method of detecting a humanoid within a surveillance area using the humanoid detector.", "Description of the Related Art Human body detection apparatuses detect humanoid intruders in a surveillance area.", "The surveillance area is an area of interest that is being surveyed to detect intruders.", "Human body detection apparatuses may also be useful in combination with air conditioning, or lighting, control apparatuses that automatically control air conditioning, or lighting, according to whether or not a human being is present in an area.", "A first type of human body detection apparatus is a pyroelectric infrared sensor that detects a human body by detecting a temperature change in a field of view.", "This type of sensor relies upon a fact that a human body temperature is higher than an ambient temperature.", "Thus, when a high-temperature object (i.e., the object's internal temperature is greater than ambient temperature) enters a field of view of a pyroelectric infrared sensor, the object radiates infrared rays that are incident on the pyroelectric infrared sensor causing the sensor to generate a voltage.", "A human body detection apparatus containing such a pyroelectric infrared sensor is preset with a threshold voltage for deciding whether or not an object which enters the field of view is a human body.", "That is, when the voltage generated by the pyroelectric infrared sensor exceeds the threshold voltage, the object is presumed to be a human body.", "The pyroelectric infrared sensor in a conventional human body detection apparatus is an infrared point sensor, and it cannot generate an infrared image.", "Therefore, a conventional human body detection apparatus that exclusively uses a pyroelectric infrared sensor cannot determine a size of an object that is radiating the infrared rays.", "Further, a human detection apparatus that exclusively uses a pyroelectric infrared sensor often cannot distinguish between incident infrared rays radiated by a human body versus those radiated by a small animal.", "Accordingly, such sensors have the problem of erroneously detecting small animals as human intruders.", "A second type of prior art human body detection apparatus uses a pyroelectric infrared image sensor.", "Such infrared image sensors can reduce the aforesaid erroneous detection of small animals as humanoid intruders by detecting the size of the subject based on the infrared image.", "However, a pyroelectric infrared image sensor is expensive as compared to an infrared point sensor.", "Also, a lens for an infrared image sensor is very expensive as compared to a lens for a visible light image sensor.", "Accordingly, the cost of a human body detector that contains a pyroelectric infrared image sensor is more expensive than other types of human body detectors.", "Also, miniaturizing a human body detection apparatus that contains a pyroelectric infrared image sensor is more difficult than with other detectors, such as those using infrared point sensors or visible light image sensors.", "A third type of human body detection apparatus contains a visible light image sensor that detects a moving body by comparing a continuously generated image.", "Upon detection of the moving body, this type of detection apparatus determines a size of the detected body and, if the body complies with predetermined parameters, decides that the body is humanoid.", "However, this type of human body detection apparatus can produce erroneous results when any large-body motion is detected, such as a curtain that is swayed by the wind.", "There are monitoring devices that have a pyroelectric infrared sensor for sensing infrared radiation to detect intruders and a visible light image sensor for recording image data of the surveillance area when a temperature difference is detected by the infrared sensor.", "But these monitoring devices merely record the image generated by the imaging element and do not use image information to electronically decide whether the body that caused the infrared radiation is humanoid.", "Thus, image recording occurs even if a small animal intrudes into the surveillance area, so long as the animal is large enough to trigger the infrared sensor's threshold setting.", "SUMMARY OF THE INVENTION The present invention solves the above-noted deficiencies of the prior art by providing a high-performance human body detector that is relatively inexpensive and more accurate than prior art detection apparatuses that rely on pyroelectric infrared image sensors and that is relatively more accurate and reliable than prior art detection apparatuses that rely on pyroelectric infrared point sensors or visible light image sensors.", "The human body detector of the present invention includes a moving body detection sensor that detects a moving body using a visible light image in combination with an infrared sensor.", "In preferred embodiments, the visible light sensor provides a signal to a human body detection circuit.", "The human body detection circuit then analyzes the size of the detected moving body and decides whether the moving body is of a size substantially equivalent to a human body size.", "The human body detection circuit also analyzes the infrared radiation detected by the infrared sensor to determine if the detected infrared radiation is substantially equivalent to infrared radiation of a human body.", "If the detection circuit determines that the size of the moving body is substantially human-size and the detected infrared radiation is above a threshold value, then the detection circuit decides that the intruder is human.", "Accordingly, the human body detector of the present invention reliably reduces erroneous detection as compared to a human body detection apparatus of the prior art that includes only a moving body detection sensor or only an infrared sensor.", "Also, the infrared sensor of the present invention need not generate an infrared image.", "Thus, the present invention may incorporate an infrared image sensor having very few pixels that does not generate an infrared image (for example, an infrared image sensor consisting of only four pixels in a 2×2 matrix).", "Such infrared image sensors are relatively inexpensive as compared to infrared image sensors that have a large plurality of pixels, which are required to generate an infrared image.", "Thus, the human body detector of the present invention can achieve low cost and small size as compared to a human body detection apparatus provided with an infrared image sensor that generates an infrared image.", "Preferably, the moving body detection sensor of the present invention is a visible light image sensor that detects a moving body by repeatedly imaging a field of view (i.e., a surveillance area).", "The moving body sensor generates a stream of sequential electrical signals corresponding to incident light on the sensor and compares those successive electrical signals and generates a difference signal that indicates whether or not a change occurred within the field of view.", "Also, in preferred embodiments, the human body detector of the present invention is arranged so that the infrared sensor and visible light image sensor share at least part of the same field of view.", "In preferred embodiments, the human body detection apparatus of the present invention is further characterized in that the human body detection circuit decides that the moving body is a human body if a level of infrared radiation, or a change in the level of infrared radiation, that is detected by the infrared sensor reaches or exceeds a predetermined value during a predetermined time interval after the size of the moving body reaches or exceeds a predetermined size.", "Alternatively, the human body detection circuit may decide that the subject is humanoid if the size of the subject exceeds a predetermined size during a particular time interval after the infrared level, or change in the infrared level, detected by the infrared sensor reaches or exceeds a predetermined value.", "Generally the time until a moving body detection sensor detects a moving body is different from the time until an infrared sensor detects the predetermined infrared level, or the change in the infrared level.", "Also, there may be instances in which the level of infrared radiation, or the change in the level of infrared radiation, reaches or exceeds the predetermined value because a part of a human being with a high temperature, such as an uncovered face or hands, enters the infrared sensor's field of view, but the size of the moving body does not reach or exceed the predetermined size because only a small portion of the human body has entered the field of view.", "Therefore, the first moment of confirmation that the size of a moving body has reached or exceeded the predetermined size and the first moment of confirmation that the infrared level, or the change in the infrared level, has reached or exceeded the predetermined value do not always coincide, and a time lag between detection signals can occur.", "The human body detector of the present invention can eliminate errors due to this sort of time lag by holding the respective signals at a high level (indicating that the size has reached the predetermined size, or the infrared radiation level has reached the predetermined value) for a preselected time interval.", "Preferably, the human body detector of the present invention uses a pyroelectric infrared sensor.", "Human body detectors are often installed in difficult access locations, such as high places, where replacement is not easy.", "Therefore, a pyroelectric infrared sensor, which has better durability than a cooled-type infrared sensor whose life is limited by the cooling device, is desirable.", "A pyroelectric infrared sensor is also preferred because it provides a signal indicating an amount of change only when the level of infrared radiation changes.", "Thus, such a sensor is more suitable for a human body detection apparatus than an infrared sensor which detects the absolute level of infrared radiation.", "The human body detector of the present invention may further include an alarm generation circuit that generates an alarm if the decision circuit decides that the moving body is a human being.", "Alternatively, the present invention may include other intrusion indicators that are triggered when the decision circuit decides that a moving body in the field of view is a human body.", "In preferred embodiments, the human body detection method of the present invention detects a moving body using a visible light image to measure a size of the moving body and an infrared sensor to detect an infrared radiation level, or a change in the infrared radiation level, within a field of view.", "The method further includes comparing the size of the moving body to a predetermined body size and comparing the amount, or change in the amount, of infrared radiation to a predetermined value to determine that the subject body is humanoid.", "Such combination of body size and infrared radiation in a surveillance field, provides a unique method of providing a reliable indication of a humanoid presence in the surveillance field.", "The human body detection method of the present invention reduces erroneous detection as compared to prior art human body detection methods which only detect the size of a moving body, or the amount of infrared rays or the amount of change in infrared rays.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic drawing of a preferred embodiment of the present invention showing a humanoid detector receiving incident light and infrared rays from an exemplary surveillance area.", "FIG. 2 is a schematic circuit diagram showing a general structure of a visible light image sensor of the present invention.", "FIG. 3 is a timing diagram showing the signal traces generated in the process of detecting an intruder.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention are described with reference to FIGS. 1-3.", "In FIG. 1, an intruder detection apparatus 1 is provided with detection head 2, infrared sensor read circuit 3, image sensor read circuit 4, decision circuit 5, and alarm generation circuit 6.", "Detection head 2 includes an infrared sensor 10 (preferably, a pyroelectric infrared point sensor), infrared lens 11 30 disposed in front of the infrared sensor 10, visible light image sensor 12 (preferably, a visible light image sensor for moving body detection), and visible light lens 13 disposed in front of the visible light image sensor 12.", "Infrared sensor 10 is connected to infrared sensor read circuit 3 via a cable 21.", "Similarly, visible light image sensor 12 is connected to the image sensor read circuit 4 via a cable 22.", "Infrared sensor read circuit 3 is connected to decision circuit 5 via a cable 23, and image sensor read circuit 4 is connected to decision circuit 5 via a cable 24.", "Decision circuit 5 is connected to alarm generation circuit 6 via a cable 25.", "Furthermore, detection head 2 is situated at a location where it can receive infrared rays 31 and visible light 32 generated from a subject 30 located within a monitoring, or surveillance, area (not numbered).", "In FIG. 1, the subject 30 is represented as a humanoid.", "The positions of the infrared sensor 10 and visible light image sensor 12 are arranged so that their field of view is shared and encompasses the detection area.", "FIG. 2 is a schematic circuit diagram showing a preferred embodiment of the visible light image sensor 12.", "In FIG. 2, a plurality of pixels 100 is disposed in a matrix.", "(For clarity, the plurality of pixels is shown as four pixels arranged in a 2×2 matrix.", "Preferred embodiments of the visible light image sensor would comprise many more pixels.) A vertical read line 102 is provided for each column of pixels 100 and is shown aligned in the vertical direction.", "The vertical read lines 102 are connected to respective transistors QX in pixel 100 and respective difference detection circuits 104.", "Each pixel 100 includes a photodiode PD that generates an electric charge corresponding to incident light.", "A junction-type field effect transistor QA, which outputs an electric signal equivalent to the charge generated by photodiode PD when in communication with the photodiode PD via switching MOS transistor QT.", "Transistor QT connects or isolates photodiode PD and transistor QA in response to signals φTGm (where "m"", "is a row number corresponding to the position of a pixel being read) from a vertical scan circuit 106.", "A reset transistor QP discharges charges that accumulate in a gate region of transistor QA.", "Switching MOS transistor QX connects or isolates vertical read line 102 and transistor QA.", "The respective difference detection circuits 104 comprise switching MOS transistors QR and QS, capacitors CR and CS, which store charges corresponding to the electrical signals output at a different times from pixel 100.", "The difference detection circuits 104 also include a comparison circuit XA, which compares the charges stored in capacitors CR and CS as described in detail below.", "FIG. 3 is a timing diagram showing signals that are generated in the course of detecting an intruder.", "Next, the operation of this embodiment is explained with reference to the figures.", "Preferably, infrared sensor 10 is a pyroelectric infrared point sensor.", "The sensor supplies infrared sensor read circuit 3 with an electrical signal corresponding to changes in the level of infrared radiation that passes through infrared lens 11 and are incident on the sensor.", "Infrared sensor read circuit 3 decides whether or not the electrical signal supplied from infrared sensor 10 has reached or exceeded a predetermined value, and generates a binary signal indicating its decision result (hereinafter "infrared signal"), and supplies it to the decision circuit 5.", "A comparator is suitable as the infrared sensor read circuit 3.", "The comparator compares a signal from the infrared sensor to a predetermined value stored in the comparator and provides the infrared signal that indicates whether the infrared sensor signal is bigger than the predetermined value.", "Furthermore, in FIG. 3, at timing trace (a), the periods t1-t2 and t7-t8 in which the infrared signal is at a high level, indicate a state in which the electrical signal supplied from infrared sensor 10 has reached or exceeded the predetermined value.", "That is, during these periods the sensor has detected a subject in the surveillance area (e.g., humanoid or small animal) with a temperature (infrared radiation) that is higher than the surroundings.", "Meanwhile, visible light image sensor 12 detects a difference between two consecutive frames at the pixel unit, and supplies image sensor read circuit 4 with a binary signal indicating whether or not the difference has reached or exceeded a predetermined value (hereinafter "difference signal"), and correlates it with each pixel.", "Here the process of generating a difference signal by visible light image sensor 12 shall be explained.", "First, at visible light image sensor 12 the optical image obtained from visible light lens 13 is focused on the photoelectric conversion face, where it is photoelectrically converted by photodiode PD in each pixel 100.", "Timing signals provided by the vertical scan circuit 106 control a transfer of signals from photodiode PD.", "The signal charge generated by photodiode PD by this sort of photoelectric conversion is transferred to the gate of transistor QA when transistor QT in pixel 100 is made conductive by timing signal φTG2 (in the case of pixel 100 located at row 2).", "If transistor QT is subsequently made nonconductive, transistor QA's gate region becomes floating, and the aforesaid signal charge from PD is held by a parasitic capacitance effect.", "That is, transistor QA's gate region stores the signal charge generated by photodiode PD and temporarily holds it.", "For lexicographic reasons, a definition of "previous frame"", "and "current frame"", "is provided.", "A "frame"", "is a set of signals from the plurality of pixels that are read in sequence.", "In the preferred embodiment of FIG. 2, signals corresponding to one row of pixels 100 are simultaneously transferred to vertical read lines 102 and transferred to difference detection circuits 104.", "Then the next row of pixels in the scanning sequence is read by transferring that row of pixel signals to the vertical read lines 102.", "After all the rows in the sequence have been read, a frame is complete.", "A subsequent frame is then read by repeating the sequence of reading the pixels row-by-row.", "After an initial frame is read (e.g., the first signal after starting the system), a legacy signal, or charge, from a previous frame remains on a gate region of the transistor QA until a current frame is to be read.", "Accordingly, the terms "previous frame"", "and "current frame"", "refer to frames of pixels read in sequence.", "Thus, in the following description a signal charge for the previous frame is already stored in transistor QA's gate region and a signal charge for a current frame is newly generated by photodiode PD and is transferred to QA after the previous frame's signal is transferred to capacitor CR, as described below.", "In this state, transistor QX in pixel 100 and transistor QR in difference detection circuit 104 are made conductive and a source follower effect operates on transistor QA, and the charge corresponding to the signal charge for the immediately previous frame stored in transistor QA's gate region charges capacitor CR in difference detection circuit 104 via vertical read line 102.", "Transistor QP in pixel 100 is made conductive and the signal charge stored in transistor QA's gate region is discharged and initialized.", "Then, transistor QT in pixel 100 is made conductive and the signal charge for the current frame newly generated by photodiode PD is transferred to transistor QA.", "Transistor QX in pixel 100 and transistor QS in difference detection circuit 104 are made conductive and a source follower effect operates on transistor QA, and the signal charge for the current frame transferred to transistor QA's gate charges capacitor CS in difference detection circuit 104 via vertical read line 102.", "That is, the charge corresponding to the signal charge for the immediately previous frame is stored in capacitor CR in difference detection circuit 104, and the charge corresponding to the signal charge for the current frame is stored in capacitor CS.", "Also, the signal charge for the current frame transferred to pixel 100's transistor QA gate is held in transistor QA's gate region, and in the next frame is used as the signal charge for the previous frame.", "Comparison circuit XA obtains an absolute value for the difference between the signal voltages corresponding to the charges on capacitors CR and CS, which represent the incident light on photodiode PD in previous and current frames, respectively.", "Thus, if CR and CS are different, a change in luminescence has occurred in the surveillance area.", "Comparison circuit XA compares the voltages on capacitors CR and CS and outputs a binary signal indicating "1"", "(a signal level indicating that change occurred) if the absolute value reaches or exceeds a predetermined value.", "Conversely, comparison circuit XA outputs a signal indicating "0"", "(a signal level indicating that change has not occurred) if the absolute value is less than the predetermined value.", "The signal output from comparison circuit XA in this manner (equivalent to a difference signal) is sequentially output from the image sensor 12 via a horizontal scanning circuit 108.", "In this manner the difference signal output from visible light image sensor 12 is supplied to image sensor read circuit 4 via cable 22.", "Based on the difference signal supplied from visible light image sensor 12, image sensor read circuit 4 calculates the number of pixels in a region that includes the portion where change occurred (hereinafter "number of moving body pixels"), and calculates a size of the moving body according to the number of moving body pixels and an optical magnification and a distance from the detection head 2 to the subject 30.", "And, based on the moving body size thus calculated, the image sensor read circuit 4 decides whether or not the moving body is approximately the size of a human body and generates a binary signal that indicates the decision result (hereinafter "moving body signal") and supplies the moving body signal to the decision circuit 5.", "For example, in a situation in which a 400,000 pixel image sensor is used as the visible light image sensor 12 and the optical magnification and distance from detection head 2 to the subject are set so that the detection area is three square meters, the area equivalent to one pixel is 0.225 cm 2 .", "If one assumes that the approximate size of a human body is 150×40 cm and that the size of a small animal is approximately 10×5 cm, then the size of a human body is equivalent to about 27,000 pixels and the size of a small animal is equivalent to about 200 pixels.", "Therefore, the image sensor read circuit 4 should decide that a moving body within the detection area is about the size of a human body if the number of moving body pixels exceeds 2,000, or so, pixels.", "Incidentally, in FIG. 3, at timing trace (c), the periods during which the moving body signal is at a high level (i.e., t4-t5 and t9-t10) indicate that a moving body about the same size as a human body is present in the detection area.", "Based on the infrared signal supplied from the infrared sensor read circuit 3 and the moving body signal supplied from the image sensor read circuit 4, detection circuit 5 decides whether or not an intruder (equivalent to a moving human body) is present, and generates a signal indicating that decision result (hereinafter "decision signal").", "The process of generating a decision signal by decision circuit 5 is described.", "First, when the infrared signal supplied from infrared sensor read circuit 3 is at a high level, thus indicating that a subject having a greater infrared radiation as compared to the surroundings has entered the detection area, decision circuit 5 holds the infrared signal in a high level state for a predetermined period of time (the periods equivalent to t1-t3 and t7-t11 in FIG. 3).", "Also, when the moving body signal supplied from the image sensor read circuit 4 is at a high level, thus indicating that a moving body about the same size as a human body is present in the detection area, the decision circuit 5 holds the moving body signal in a high level state for a predetermined period of time (the periods t4-t6 and t9-t12 in FIG. 3).", "When the infrared signal after holding (shown as trace (b) in FIG. 3) and the moving body signal after holding (trace (d) in FIG. 3) are both at a high level (time interval t9-t11 in FIG. 3), the decision circuit 5 generates a high level signal (indicating that an intruder is present) as the decision signal.", "That is, the interval during which the infrared signal and the moving body signal both go high, as in time intervals t9-t11 in FIG. 3, the decision signal is made high to indicate that a human being has intruded into the detection area.", "At the moment that the decision signal generated by decision circuit goes high, alarm generation circuit 6 may be arranged to generate an alarm indicating that an intruder has been detected.", "Furthermore, the interval during which an alarm is generated is not limited to the interval during which the decision signal is at a high level.", "For example, this period may be from the moment the decision signal temporarily goes high until an alarm stop switch (not shown in drawings) is operated.", "Alternatively, the decision signal may also be used to operated other systems such as video recording devices or video monitors.", "As stated, in preferred embodiments, the infrared signal and moving body signal are held for a predetermined time interval.", "In a preferred embodiment, the visible light image sensor 12 generates a difference signal every 1/30th of a second (approximately once every 33ms), whereas the hold period for the infrared sensor 10 is about 100 ms.", "Therefore, there is little possibility of the infrared signal (FIG.", "3, trace (a)) and the moving body signal (FIG.", "3, trace (c)) both going high simultaneously unless the signals are held high for a predetermined time interval after they are triggered high by detection of infrared rays or image size, respectively.", "Also, there can be instances in which the amount of change in infrared rays exceeds the predetermined value because some portion of a human being such as a face or hands, which are typically exposed and thus have higher infrared radiation as compared to clothed body portions, enters the field of view of the infrared sensor 10, but the size of the detected moving body (face or hands) does not yet exceed the predetermined size.", "When more of the subject body enters the field of view, the change in infrared radiation may be below the predetermined value, but the subject image size is now greater than its respective predetermined value.", "However, because both signals are not exceeding their respective predetermined values, the decision signal remains low indicating no intruder.", "This situation could lead to a failure to detect an intruder.", "Thus, occurrences of the aforesaid detection failures can be reduced by holding the infrared signal and the moving body signal high for a predetermined time interval after they are triggered high by detection of infrared rays (amount or change in amount) and image size, respectively.", "However, erroneous detection may also occur if the hold period is too long.", "A preferred hold period is approximately a few seconds.", "The decision signal is at a low level, indicating no intruder, in the period during which only the infrared signal is high (FIG.", "3, time intervals t1-t3) and in the period during which only the moving body signal is high (FIG.", "3, time intervals t4-t6).", "Thus, an intruder indication does not occur, or is unlikely, when the subject detected is a small animal or a moving body whose temperature is about the same as its surroundings (for example, a swaying curtain).", "The intruder detector of the present invention permits the respective fields of view of the infrared sensor 10 and the visible light image sensor 12 to be arranged so as to include all of the detection/surveillance area, so that intruders can be detected with good accuracy.", "The intruder detector of the present invention includes the visible light image sensor 12 for generating the difference signal.", "Thus, the detector of the present invention does not need peripheral circuits such as an A/D conversion circuit, image memory, and image processing circuit that are mandatory in the case of many prior art detection apparatuses that are equipped with a visible light image sensor for generating simple image data.", "The embodiments describe above include a pyroelectric infrared point sensor for detecting infrared radiation amounts or changes.", "However, an inexpensive infrared image sensor having few pixels, (for example, four pixels in a 2×2 matrix) is also suitable for detecting subjects that have a temperature that is higher than its surroundings.", "Also, this embodiment decides the size of a moving body using the number of moving body pixels, but other methods may be suitable to decide the size of the moving body.", "For example, a method that uses the number of pixels that change or a method that extracts the edge portion of the moving body by analyzing difference signals.", "Other methods are also suitable.", "In addition, in this embodiment infrared sensor 10 and visible light image sensor 12 have a common field of view and their position is adjusted in advance to include all of the detection area.", "But, for example, when the infrared sensor field of view and the visible light image sensor field of view are narrower than the detection area, it is possible to detect an object having a higher temperature than its surroundings within the detection area using a plurality of infrared sensors with different fields of view, and combine the field of view of a visible light image sensor with the field of view of an infrared sensor which detected an object having a higher temperature than the surroundings.", "In other alternative embodiments, a difference signal may be generated by comparison of images.", "For example, the output of a visible light image sensor that generates simple image data may be converted by an A/D converter, and the image data for two consecutive frames may be stored in an image memory.", "Then the difference between two consecutive frames at the pixel unit may be detected using the digital image data held in the image memory, thereby generating a difference signal.", "In alternative embodiments, the fields of view of the infrared sensor 10 and the visible light image sensor 12 are not identical or overlapping.", "For example, if the field of view of the infrared sensor 10 and the field of view of the visible light image sensor 12 are adjacent and the separation between each sensor's field of view is small, the system may decide whether or not the conditions of a high infrared radiation subject and a humanoid sized subject are the same subject by adjusting the time period during which the infrared signal is held at a high level or the time period during which the moving body signal is held at a high level, or both.", "In another alternative embodiment, the detection of an object of higher temperature than its surroundings may be detected by using a thermal-type infrared sensor such as a pyrometer.", "In addition, the intruder detector of the present invention generates a difference signal based on a visible light optical image.", "Thus, preferred embodiments are suitable for detecting an intruder during the day.", "However, alternative embodiments of the invention can detect an intruder at night by illuminating the detection area with near-infrared light (for example, near 800 nm), to which visible light image sensor 12 is sensitive.", "In the above-described embodiments, the image sensor read circuit 4, decision circuit 5, and alarm generation circuit 6 are portrayed as discrete circuits.", "Alternatively, the image sensor drive circuit 4, decision circuit 5, and alarm generation circuit 6 may be fabricated as integrated circuits.", "Furthermore, because of miniaturization in semiconductor chip technology, preferably these circuits are fabricated on a single integrated circuit.", "The present invention encourages miniaturization and cost reduction by making it possible to detect a moving body using a simple circuit structure without providing peripheral circuits such as an A/D conversion circuit, image memory, and image processing circuits.", "Thus, this invention makes it possible to reduce erroneous detection as compared to an intruder detection apparatus equipped with a visible light image sensor or pyroelectric-type infrared point sensor alone.", "Further, this invention can maintain a low cost as compared to an intruder detection apparatus equipped with an infrared image sensor.", "Furthermore, the present invention eliminates the time lag between the first moment of confirmation that the size of a moving body has reached or exceeded the specified size and the first moment of confirmation that the amount of infrared rays or the amount of change in infrared rays within the detection area due to the moving body has reached or exceeded the specified value.", "This method thus reduces detection failures.", "In the image sensor of the present invention, the difference detection circuit 104 compares pixel signals of current and previous frames.", "As described, the pixel signals are successive signals, that are time sequenced pixel signals that are provided to the difference detection circuit one after another.", "However, other sequences are also suitable and may be employed to reduce the size of the image signal (not the size of the detected image) or increase the system speed.", "Thus, a current frame pixel signal may be compared to a pixel signal from several frames earlier.", "This may be less accurate, but may nonetheless be suitable in some applications.", "This specification sets forth the best mode for carrying out the invention as known at the time of filing the patent application and provides sufficient information to enable a person skilled in the art to make and use the invention.", "The specification further describes preferred materials, shapes, configurations and arrangements of parts for making a using the invention.", "However, other such materials, shapes, configurations, and arrangements may by used and it is intended that the scope of the invention shall only be limited by the language of the claims and the law of the land as pertains to valid U.S. patents." ]
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to an organic electroluminescent device, and in particular, to an organic electroluminescent device comprising a luminous layer provided between a first electrode and a second electrode, and a reflective layer provided on the first electrode side for reflecting light emitted from the luminous layer and emitting the light from the second electrode side. [0003] 2. Description of the Related Art [0004] Organic electroluminescent devices (organic EL devices) generally have a structure where an organic layer that includes a luminous layer having a thickness of approximately several tens of nm to several hundreds of nm is sandwiched between an electrode having reflecting properties and an electrode having translucence. In such organic EL devices, light that has been emitted from the luminous layer interferes in the device structure before being emitted to the outside. Conventionally, it has been attempted to use such interference to increase the luminous efficiency. [0005] Japanese Unexamined Patent Publication 2002-289358 proposes a technology where interference between light that has been emitted from a luminous layer in the direction toward an electrode having translucence and light that has been emitted in the direction toward an electrode having reflecting properties is used to increase the luminous efficiency by setting the distance between the light-emitting position and the reflective layer to such a distance that emitted light has such a wavelength as to resonate. [0006] In Japanese Unexamined Patent Publication 2000-243573, reflection from the interface between an electrode having translucence and a substrate is also taken into consideration, and the distance between the light-emitting position and an electrode having reflecting properties, and the distance between the light-emitting position and the interface between the electrode having translucence and the substrate are both defined. [0007] In the pamphlet of International PCT Patent Publication WO01/039554, interference caused by multiple reflection of light between an electrode having translucency and an electrode having reflecting properties is used to increase the luminous efficiency, by setting the film thickness between the electrode having translucence and the electrode having reflecting properties to such a thickness that light having a desired wavelength resonates. [0008] In all of the above described prior art technologies, interference of emitted light is used to increase the luminous efficiency. [0009] Meanwhile, there is a problem with light that has been emitted from an organic EL device, such that the color tone varies depending on the view angle. Conventionally, the use interference of emitted light in order to reduce such change in the color tone depending on the view angle has not been considered. [0010] In addition, interference as that described above occurs inside organic EL devices having a white luminous layer, and therefore, it is preferable for the light-emitting position to be in proximity to the reflective layer, preferably a distance of no greater than 80 nm, in order for white light having components of a wide range of wavelengths to be emitted efficiently. However, when the light-emitting position is at a distance from the reflective layer, making the distance between the two greater, it becomes difficult for white light having a wide range of spectra to be emitted by means of interference. [0011] Japanese Unexamined Patent Publication 2004-79421 discloses that the distance between the light-emitting position and a reflective layer, and the distance between the light-emitting position and the interface between an electrode having translucence and an external layer are defined, and thereby, an efficient device having excellent white chromaticity can be gained. SUMMARY OF THE INVENTION [0012] A first object of the present invention is to provide an organic EL device which can reduce the change in the color tone depending on the view angle. [0013] A second object of the present invention is to provide an organic EL device which can gain excellent white chromaticity. [0014] The present invention provides an organic electroluminescent device comprising: a luminous layer provided between a first electrode and a second electrode; and a reflective layer provided on the first electrode side for reflecting light emitted from the luminous layer and emitting the light from said second electrode side; wherein an optical distance L 1 between a light-emitting position of the luminous layer and the reflective layer is determined so as to allow the light with wavelength λ, which is center wavelength of the emitted light to be taken out, to increase in intensity as a result of interference, and wherein an optical distance L 2 between a reflective interface at the device end portion on the second electrode side and the reflective layer is determined so as to allow the light with wavelength λ to decrease in intensity as a result of interference. [0015] According to the present invention, the optical distance L 1 between the light-emitting position of the luminous layer and the reflective layer is an optical distance for allowing the light having the center wavelength λ to increase in intensity as a result of interference, and the optical distance L 2 between the reflective interface of the device end portion on the second electrode side and the reflective layer is an optical distance for allowing light having the wavelength λ to decrease in intensity as a result of interference. In the following, interference of light caused by the optical distance L 1 is referred to as “first interference,” and interference of light caused by the optical distance L 2 is referred to as “second interference.” [0016] The first interference and the second interference of the present invention are described in reference to FIG. 2 . [0017] In the organic EL device shown in FIG. 2 , a reflective layer 34 is formed on top of a substrate 37 , and a first electrode 31 is provided on top of the reflective layer 34 . An organic layer 38 that includes a luminous layer is provided on top of the first electrode 31 . In the present embodiment, the luminous layer in the organic layer 38 is formed by making a host material contain a dopant material. The position of light emission 33 a in the organic layer 38 generally differs depending on the carrier transportability of the host material in the luminous layer. According to the present invention, in the case where the host material of the luminous layer has electron transportability, the interface between the luminous layer and the hole transport layer becomes the light-emitting position 33 a. In addition, in the case where the host material of the luminous layer has hole transportability, the interface between the electron transport layer and the luminous layer becomes the light-emitting position 33 a. In the case where the luminous layer has both properties of electron transportability and hole transportability, so-called bipolar transportability, the center area in the direction of the thickness of the luminous layer becomes the light-emitting position 33 a. [0018] A second electrode 32 is provided on top of the organic layer 38 . In the present embodiment, the second electrode 32 is the top layer of the device, and there is a layer of air above the second electrode 32 . [0019] L 1 is the optical distance between the light-emitting position 33 a and the reflective layer 34 , and L 2 is the optical distance between the upper end portion 32 a of the second electrode 32 and the reflective layer 34 . The outside of the second electrode 32 is a layer of air, and reflection occurs from the interface between the second electrode 32 and the layer of air, due to the difference in the index of refraction between the second electrode 32 and the layer of air. Accordingly, the upper end portion 32 a of the second electrode 32 becomes the reflective interface of the device end portion. [0020] The first interference 40 occurs as interference between light 41 that is emitted from the light-emitting position 33 a toward the second electrode 32 side, and light 42 which is emitted from the light-emitting position 33 a toward the first electrode 31 side, and is reflected from the reflective layer 34 so as to be emitted to the second electrode 32 side. [0021] The second interference 50 is interference which occurs as a result of multiple reflection of light 51 that has been emitted from the light-emitting position 33 a, which is reflection of light from the interface 32 a between the second electrode 32 and the layer of air and reflection of light from the reflective layer 34 . [0022] The first interference 40 depends on the optical distance L 1 between the light-emitting position 33 a and the reflective layer 34 . In addition, the second interference 50 depends on the optical distance L 2 between the reflective interface 32 a of the device end portion and the reflective layer 34 . [0023] The efficiency of light emission from the device is influenced both by the above described first interference 40 and the second interference 50 . [0024] Here, in order to describe the change in the color tone depending on the view angle, which has conventionally been a problem, the first interference and the second interference are examined, taking the view angle into consideration. FIG. 3 is a diagram showing a view angle θ. As shown in FIG. 3 , in the case where the view angle is θ, the conditions for resonance between the first interference and the second interference can be represented by the following formulas (6) and (7). 2 L 1 cos θ−λ φ 1 /2 π=m λ   (6) 2 L 2 cos θ−λ(φ 1 +φ 2 )/2 π=m λ   (7) [0025] Here, m is a natural number, including 0, L 1 is the optical distance between the light-emitting position and the reflective layer, L 2 is the optical distance between the reflective interface of the device end portion and the reflective layer, λ is a resonant wavelength, φ 1 is the phase shift when light is reflected from the reflective layer, and φ 2 is the phase shift when light is reflected from the reflective interface of the device end portion. [0026] As is clear from the above described formulas (6) and (7), the resonant wavelength between the first interference and the second interference shifts to the shorter wavelength side as the view angle θ increases. The taking-out efficiency is the sum of both effects; the first interference and the second interference, and this also shifts to the shorter wavelength side when the view angel increases. [0027] FIG. 4 is a graph illustrating a state where the wavelengths of light that is emitted from the device have shifted to the shorter wavelength side as the view angle increases. It can be seen in the spectrum A having a small half value width, as shown in FIG. 4 , that change in the color tone and brightness is greater when the view angle increases and the wavelengths shift to the shorter wavelength side. In contrast it can be seen in the spectrum B having a large half value width that change in the color tone and brightness is small even when the view angle increases and the wavelengths shift to the shorter wavelength side. The present invention provides a spectrum where the taking-out efficiency where the half value width is large in manner described above, and the peak of the spectrum is flat, and thereby, change in the color tone and brightness due to change in the view angle becomes small. In the following, how the present invention can provide taking-out efficiency where the half value width is large and the peak is flat in the manner described above is described. [0028] In the present invention, L 1 is an optical distance for allowing light having the wavelength λ to increase in intensity by means of interference. Accordingly, the first interference is interference for making light having the wavelength λ resonate. Meanwhile, L 2 is an optical distance for allowing light having the wavelength λ to decrease in intensity by means of interference. Therefore, the second interference makes light having the wavelength λ non-resonant, and is interference having respective resonant wavelengths on the shorter wavelength side and on the longer wavelength side of λ. The actual taking-out efficiency is affected both by the first interference and the second interference, and therefore, when these are added, the taking-out efficiency forms a flat spectrum having a large half value width. Accordingly, the present invention provides a flat spectrum for the taking-out efficiency having a large half value width, for example, the spectrum B shown in FIG. 4 . Accordingly, as described above, change in the color tone and brightness depending on the view angle can be reduced. [0029] According to the present invention, in the case where the luminous layer is a monochrome luminous layer, it is preferable for the optical distances L 1 and L 2 to satisfy the following formulas (1) to (5). 2 L 1 −λ 1 φ 1 /2 π=mλ 1   (1) 2 L 2 −λ 2 (φ 1 +φ 2 )/2π=( n+ ½)λ 2   (2) λ f −30<λ<λ f +80   (3) λ−15<λ 1 <λ+15   (4) λ−15<λ 2 <λ+15   (5) [0030] (unit for λ: nm) [0031] Here, m and n are natural numbers, L 1 is the optical distance between the light-emitting position and the reflective layer, L 2 is the optical distance between the reflective interface of the device end portion and the reflective layer, λ f is the fluorescence peak wavelength of the luminous layer, φ 1 is the phase shift when light is reflected from the reflective layer, and φ 2 is the phase shift when light is reflected from the reflective interface of the device end portion. [0032] φ 1 can be represented by the following formula when the index of refraction of the first electrode is n e , the index of refraction of the reflective layer is n m , and the extinction coefficient of the reflective layer is k m . φ 1 =tan −1 {2 n e k m /( n e 2 −n m 2 −k m 2 )} [0033] Here, when 2n e k m /(n e 2 −n m 2 −k m 2 )>0, 0<φ 1 <π/2, and when 2n e k m /(n e 2 −n m 2 −k m 2 )<0, π/2<φ 1 <π. [0034] In addition, φ 2 is 0 when the index of refraction of the second electrode is greater than that of the layer outside of the device, and is π when the index of refraction of the second electrode is smaller than that of the layer outside of the device. [0035] In the above described formula (3), the lower limit value of λ is λ f −30, and the upper limit value of λ is λ f +80, where the upper limit value is wider because the fact that the spectrum of taking-out efficiency shifts to the shorter wavelength side when the view angle increases is taken into consideration. [0036] In the present invention, “monochrome” means a color other than white, and colors such as blue, green, red and orange can be cited as examples. [0037] According to the present invention, in the case where the luminous layer is a white light-emitting layer, it is preferable for the optical distances L 1 and L 2 to satisfy the following formulas (1) to (5). 2 L 1 −λ 1 φ 1 /2 π=mλ 1   (1) 2 L 2 −λ 2 (φ 1 +φ 2 )/2π=( n+ ½)λ 2   (2) λ f −30<λ<λ f +80   (3) λ−15<λ 1 <λ+15   (4) λ−15<λ 2 <λ+15   (5) λ f −30<λ<λ f +80   (3) λ−15<λ 1 <λ+15   (4) λ−15<λ 2 <λ+15   (5) [0038] (unit for λ: nm) [0039] Here, m and n are natural numbers, L 1 is the optical distance between the light-emitting position and the reflective layer, L 2 is the optical distance between the reflective interface of the device end portion and the reflective layer, λ is the center wavelength in the range of wavelengths of white light for emission, φ 1 is the phase shift when light is reflected from the reflective layer, and φ 2 is the phase shift when light is reflected from the reflective interface of the device end portion. [0040] φ 1 can be represented by the following formula when the index of refraction of the first electrode is n e , the index of refraction of the reflective layer is n m , and the extinction coefficient of the reflective layer is k m . φ 1 =tan −1 {2 n e k m /( n e 2 −n m 2 −k m 2 )} [0041] Here, when 2n e k m /(n e 2 −n m 2 −k m 2 )>0, 0<φ 1 <π/2, and when 2n e k m /(n e 2 −n m 2 −k m 2 )<0, π/2<φ 1 <π. [0042] In addition, φ 2 is 0 when the index of refraction of the second electrode is greater than that of the layer outside of the device, and is π when the index of refraction of the second electrode is smaller than that of the layer outside of the device. [0043] In general, the second electrode is an electrode having translucence, and therefore, is formed of a thin layer of a conductive metal oxide or a metal thin film. Accordingly, in the case where the outside of the second electrode is a layer of air, a layer of resin or a layer of glass, the interface between the second electrode and this external layer becomes a reflective interface. On the other hand, in the case where an inorganic protective layer or the like is provided outside of the second electrode, the difference in the index of refraction between the second electrode and the inorganic protective layer is small, and therefore, in some cases, the outside of the second electrode does not become a reflective interface. In such a case, the outside of the inorganic protective layer becomes the reflective interface. [0044] According to the present invention, as described above, the light-emitting position from the luminous layer is the interface between the luminous layer and the layer that is adjacent to the luminous layer on the first electrode side (for example, the hole transport layer) in the case where the host material of the luminous layer has electron transportability, and is the interface between the luminous layer and the layer that is adjacent to the luminous layer on the second electrode side (for example, the electron transport layer) in the case where the host material of the luminous layer has hole transportability. [0045] According to the present invention, it is preferable for the thickness of the metal layer to be no greater than 5 nm in the case where a metal layer is provided between the organic layer that includes the luminous layer and the second electrode. The thickness of the metal layer is made to be no greater than 5 nm, and thereby, the effects of the reflection of light from this metal layer on the first interference and the second interference can be reduced. [0046] According to the present invention, it is preferable for the luminous layer to be formed of a host material and a dopant material. As the host material of the luminous layer, anthracene derivatives, aluminum complexes, rubrene derivatives, aryl amine derivatives and the like can be cited. According to the present invention, the luminous layer may be formed of two layers, where, for example, a blue light-emitting layer and an orange light-emitting layer are laminated, or may be formed of only one layer in the case where the luminous layer is a white light-emitting layer. [0047] As for the dopant material, a singlet luminous material may be used, or a triplet luminous material may be used. In order to gain high efficiency of light emission, it is preferable to use a triplet luminous material which is a phosphorescent material. As the singlet luminous material, perylene derivatives, coumarin derivatives, anthracene derivatives, tetracene derivatives, stilbene derivatives and the like can be cited. In addition, as the triplet luminous material (phosphorecent material), iridium complexes, platinum complexes and the like can be cited. [0048] According to the present invention, an organic layer other than the luminous layer may be provided. As the organic layer, carrier transport layers, such as hole transport layers and electron transport layers can be cited. As the material having hole transportability that is used for the hole transport layer, aryl amine derivatives and the like can be cited. In addition, as the material having electron transportability that is used for the electron transport layer, perylene derivatives, anthraquinone derivatives, anthracene derivatives, rubrene derivatives and the like can be cited. [0049] According to the present invention, the second electrode is generally formed of an electrode having translucence. As this electrode having translucence, translucent conductive metal oxide, such as ITO (indium tin oxide), IZO (indium zinc oxide) and tin oxide, can be cited. [0050] According to the present invention, the first electrode may be formed of an electrode having translucence, such as a conductive metal oxide, in the same manner as with the second electrode, or may be formed of a metal thin film or the like. In the case where the first electrode is formed of a metal thin film, it may also be used as the reflective layer according to the present invention. [0051] According to the present invention, the reflective layer is not particularly limited, as long as it can reflect light, and is generally formed of a metal thin film. As the metal thin film, Ag, Al, Mo, Cr and the like can be cited. Though the film thickness of the reflective layer is not particularly limited, it is generally preferable for it to be within a range from 100 nm to 300 nm. [0052] An organic electroluminescent display according to the present invention is provided with an organic electroluminescent device having a device structure that is sandwiched between an anode and a cathode, an active matrix driving substrate where active devices for supplying a display signal which corresponds to each display pixel to the organic electroluminescent device, and a translucent sealing substrate that is provided so as to face the active matrix driving substrate, which is a top emission type organic electroluminescent display where the organic electroluminescent device is placed between the active matrix driving substrate and the sealing substrate, and the electrode, which is either the cathode or the anode, and provided on the sealing substrate side is a translucent electrode, characterized in that the organic electroluminescent device is an organic electroluminescent device according to the above described present invention. [0053] A color filter of which the color tone is of the same type as the color of the emitted light may be placed between the sealing substrate and the organic electroluminescent device. A color filter of which the color tone is of the same type as the emitted light is used, and thereby, the change in the color tone depending on the view angle can further be reduced, and furthermore, a luminous display device of which the dependency on the view angle is small can be gained. [0054] The organic electroluminescent display according to the present invention is a top emission type display, and therefore, light that is emitted from the organic electroluminescent device is emitted from the sealing substrate on the side opposite to the side where the active matrix is provided. Generally, an active matrix circuit is formed by laminating a number of layers, and in the case of a bottom emission type, emitted light is attenuated due to the existence of this active matrix circuit, but the organic electroluminescent display according to the present invention is of a top emission type, and therefore, light can be emitted without being influenced by this active matrix circuit. In particular, the organic electroluminescent device according to the present invention has a number of luminous units, and the top emission type has fewer films through which emitted light transmits, in comparison with bottom emission types, and therefore, freedom of design for controlling attenuation of emitted light and narrowing of the view angle of emitted light by means of interference of light is increased. [0055] According to the present invention, the spectrum of the efficiency of light emission from the device can be made to be a flat spectrum having a large half value width. Accordingly, the change in the color tone depending on the view angle and the change in the brightness can be reduced, and thus, a luminous display of which the dependency on the view angle is small can be gained. [0056] In addition, in the case where the luminous layer is a white light-emitting layer, light can be emitted approximately evenly throughout the entirety of the wide range of wavelengths of white. Accordingly, emission of white light having excellent chromaticity can be gained. BRIEF DESCRIPTION OF THE DRAWINGS [0057] FIG. 1 is a schematic cross sectional diagram showing an organic EL device according to one embodiment of the present invention; [0058] FIG. 2 is a schematic cross sectional diagram illustrating the first interference and the second interference according to the present invention; [0059] FIG. 3 is a schematic diagram showing the view angle θ; [0060] FIG. 4 is a graph showing the change in spectrum of the taking-out efficiency depending on the view angle; [0061] FIG. 5 is a graph showing the results of simulation of the taking-out efficiency in an organic EL device according to Comparative Example 1; [0062] FIG. 6 is a graph showing the change in spectrum of emitted light depending on the view angle in the organic EL device according to Comparative Example 1; [0063] FIG. 7 is a graph showing the results of simulation of the taking-out efficiency in an organic EL device according to Example 1; [0064] FIG. 8 is a graph showing the change in spectrum of emitted light depending on the view angle in the organic EL device according to Example 1; [0065] FIG. 9 is a graph showing the actual taking-out efficiency in Example 1 and Comparative Example 1; [0066] FIG. 10 is a schematic cross sectional diagram showing an organic EL device according to another embodiment of the present invention; [0067] FIG. 11 is a graph showing the results of simulation of the taking-out efficiency in an organic EL device according to Example 2; [0068] FIG. 12 is a graph showing the results of simulation of the taking-out efficiency in an organic EL device according to Comparative Example 2; [0069] FIG. 13 is a graph showing the change in spectrum of emitted light in the organic EL devices of Example 2 and Comparative Example 2; [0070] FIG. 14 is a graph showing the actual taking-out efficiency in Example 2 and Comparative Example 2; [0071] FIG. 15 is a cross sectional diagram showing a bottom emission type organic EL display using an organic EL device according to an embodiment of the present invention; and [0072] FIG. 16 is a cross sectional diagram showing an organic EL display according to an embodiment of the present invention. DESCRIPTION OF PREFERRED EMBODIMENTS [0073] In the following, the embodiments of the present invention are more concretely described, but the present invention is not limited to these embodiments. EXAMPLE 1 [0074] An organic EL device having the device structure shown in FIG. 1 was fabricated. As shown in FIG. 1 , a reflective layer 34 (having a film thickness of 100 nm) was formed of Ag on top of a glass substrate 37 , a first electrode 31 (having a film thickness of 65 nm) was formed of ITO (indium tin oxide) on top of this, and a hole transport layer 35 (having a film thickness of 120 nm) was formed on top of this. [0075] A green light-emitting layer 33 (having a film thickness of 40 nm) was formed on top of the hole transport layer 35 , and an electron transport layer 36 (having a film thickness of 15 nm) was formed on top of this. A second electrode 32 was formed on top of the electron transport layer 36 . The second electrode 32 was formed of IZO (indium zinc oxide) (having a film thickness of 140 nm). An Li layer (having a film thickness of 0.3 nm) and an Au layer (having a film thickness of 1.5 nm) were formed as metal layers between the second electrode 32 and the electron transport layer 36 . Accordingly, an Li layer/Au layer/IZO layer was formed on top of the electron transport layer 36 . [0076] The green light-emitting layer was formed using TBADN as the host material, and 2 weight % of C545T was made to be contained as the dopant material. [0077] TBADN is 2-tertiary-butyl-9,10-di(2-naphthyl) anthracene, and has the following structure. C545T has the following structure. [0078] The hole transport layer 5 was formed of NPB. NPB is N, N′-di(naphthacene-1-yl)-N,N′-diphenyl benzidine, and has the following structure. [0079] The electron transport layer 6 was formed of BCP. BCP is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, and has the following structure. Comparative Example 1 [0080] An organic EL device according to Comparative Example 1 was fabricated in the same manner as in the above described Example 1, except that the film thickness of IZO was changed from 140 nm in the above described Example 1 to 70 nm. [0081] [Calculation of Resonant Wavelengths λ 1 and λ 2 ] [0082] The resonant wavelength λ 1 resulting from the first interference in Example 1 and Comparative Example 1, and resonant wavelength λ 2 resulting from the second interference were calculated using the formulas (1) and (2). The results of calculation are shown in Table 1. Here, the optical constants, such as the index of refraction n and the extinction coefficient k, are dependent on the wavelength, and therefore, the optical constants for a wavelength of 520 nm as shown in Table 2, were used for λ 1 and λ 2 of Example 1, the optical constants for a wavelength of 540 nm were used for λ 1 of Comparative Example 1, and the optical constants for a wavelength of 640 nm were used for λ 2 of Comparative Example 1 for calculation. Here, 520 nm, 540 nm and 640 nm were respectively estimated from the approximate values of λ 1 and λ 2 , which were separately calculated. More precise calculation can be carried out through simulation using a computer. [0083] The fluorescence peak wavelength λ f of the luminous layer was 500 nm. TABLE 1 λ 1 λ 2 Ex. 1 531 nm 514 nm Comp. 528 nm 621 nm Ex. 1 [0084] TABLE 2 n(Organic n(Ag) k(Ag) n(ITO) Layer) n(IZO) 520 nm 0.0524 3.05 2.04 1.81 2.04 540 nm 0.0542 3.23 2.03 1.81 2.03 640 nm 0.066 4.11 1.97 1.78 1.97 [0085] In Comparative Example 1, the fluorescence peak wavelength λ f of the luminous layer was 500 nm, λ 1 was 528 nm, and λ 2 was 621 nm. As is clear from the above described formulas (3) and (5), λ 2 deviates from the range of the present invention, and it is clear that the organic EL device of Comparative Example 1 is out of the scope of the present invention. [0086] FIG. 5 is a graph showing the results of simulation of the taking-out efficiency in Comparative Example 1. As is clear from FIG. 5 , both the first interference and the second interference show a large taking-out efficiency in a green region, and as a result of this, the total taking-out efficiency forms a spectrum of the taking-out efficiency having a maximum in the vicinity of 520 nm, which is green, and a small half value width. As described above, the spectrum of this taking-out efficiency shifts to the shorter wavelength side when the view angle increases. FIG. 6 shows the spectrum of light emitted from this device at view angles of 0°, 30° and 60°. In Comparative Example 1, the half value width of the spectrum of the taking-out efficiency is small, and therefore, as shown in FIG. 6 , when the view angle increases, the color of the emitted light greatly changes. [0087] The actual taking-out efficiency is gained by dividing the spectra of FIG. 6 by the spectra of light emitted from the inside of the device, and the results are shown in FIG. 9 . Here, as for the spectra of the light emitted from the inside, spectra gained from an organic EL device where the reflective layer did not contain Ag and the structure of remaining portions was the same was used. In the case where there was no reflective layer, the effects of interference were small, and the luminescence can be considered to be approximately equal to the internal luminescence. [0088] It can be seen, as shown in FIG. 6 , that the actual taking-out efficiency in the comparative example is approximately equal to the simulation, and has a small half value width. [0089] In Example 1, the fluorescence peak wavelength λ f of the luminous layer is 500 nm, λ 1 is 531 nm, and λ 2 is 514 nm, which is within the range of the present invention. FIG. 7 is a graph showing the results of simulation of the taking-out efficiency in this example. As is clear from FIG. 7 , in the first interference, the taking-out efficiency in the green region is high, and in the second interference, the taking-out efficiency in blue and red is high. The total taking-out efficiency from this device is influenced by these two interferences, and a high taking-out efficiency can be gained throughout the entirety of a wide wavelength region, as shown in FIG. 7 . [0090] FIG. 8 is a graph showing spectra of light emitted from this device at a view angle of 0°, 30° and 60°. It can be seen, as is clear from FIG. 8 , that the color of emitted light barely changes depending on the view angle. The actual taking-out efficiency can be gained by dividing the spectrum at the view angle of 0° shown in FIG. 8 by the internal luminescence. [0091] FIG. 9 shows the actual taking-out efficiency in the example. It can be seen, as is clear from FIG. 9 , that, the taking-out efficiency from the device of the example is approximately constant throughout a wide range of wavelengths. Table 3 shows the color tone and the change in the brightness (the brightness is 100% when the view angle is 0°) of the organic EL devices of Example 1 and Comparative Example 1 at view angles of 0°, 30° and 60°. TABLE 3 View Angle 0° 30° 60° Ex. 1 Chromaticity (0.256, 0.596) (0.267, 0.592) (0.228, 0.628) (x, y) Brightness % 100 100   85.3 Comp. Chromaticity (0.217, 0.696) (0.161, 0.679) (0.133, 0.535) Ex. 1 (x, y) Brightness % 100 94.5 49.2 [0092] It can be seen, as is clear from the results shown in Table 3, that the change in the color tone and brightness depending on the view angle has been reduced in the organic EL device of Example 1 in comparison with Comparative Example 1. EXAMPLE 2 [0093] An organic EL device having the device structure shown in FIG. 10 was fabricated. As shown in FIG. 10 , a reflective layer 34 (having a film thickness of 100 nm) was formed of Ag on top of a glass substrate 37 , a first electrode 31 (having a film thickness of 65 nm) was formed of ITO (indium tin oxide) on top of this, and a hole transport layer 35 (having a film thickness of 100 nm) was formed on top of this. [0094] An orange light-emitting layer 33 c (having a film thickness of 15 nm) and a blue light-emitting layer 33 b (having a film thickness of 25 nm) were formed in this order on top of the hole transport layer 35 . A white light-emitting layer 33 was formed of the blue light-emitting layer 33 b and the orange light-emitting layer 33 c, and an electron transport layer 36 (having a film thickness of 10 nm) was formed on top of this white light-emitting layer 33 . A second electrode 32 was formed on top of the electron transport layer 36 . The second electrode 32 was formed of IZO (indium zinc oxide) (having a film thickness of 30 nm). An Li layer (having a film thickness of 0.3 nm) and an Au layer (having a film thickness of 1.5 nm) were formed as metal layers between the second electrode 32 and the electron transport layer 36 . Accordingly, an Li layer/Au layer/IZO layer was formed on top of the electron transport layer 36 . [0095] In the present example, the white light-emitting layer 33 is formed of a blue light-emitting layer 33 b and an orange light-emitting layer 33 c, and therefore, the interface between the blue light-emitting layer 33 b and the orange light-emitting layer 33 c becomes the light-emitting position 33 a. [0096] The orange light-emitting layer 33 c was formed using NPB as the host material, and 3 weight % of DBZR was made to be contained as a dopant material. [0097] DBzR is 5,12-bis{4-(6-methyl benzothiazole-2-yl) phenyl}-6,11-diphenyl naphthacene, and has the following structure. [0098] The blue light-emitting layer 33 b was formed using TBADN as the host material, and 2 weight % of TBP was made to be contained as a dopant material. [0099] TBP is 2,5,8,11-tetra-tertiary-butyl perylene, and has the following structure. [0100] The hole transport layer 35 is formed of NPB. [0101] The electron transport layer 36 is formed of BCP. Comparative Example 2 [0102] The organic EL device of Comparative Example 2 was fabricated in the same manner as in the above described Example 2, except that the film thickness of the hole transport layer 35 was made to be 45 nm, the film thickness of the orange light-emitting layer 33 c was made to be 30 nm, and the film thickness of the blue light-emitting layer was made to be 40 nm in the above described Example 2. [0103] [Calculation of Resonant Wavelengths λ 1 and λ 2 ] [0104] The resonant wavelength λ 1 resulting from the first interference and the resonant wavelength λ 2 resulting from the second interference in Example 2 and Comparative Example 2 were calculated using the formulas (1) and (2). The results of calculation are shown in Table 4. Here, the optical constants, such as the index of refraction n and the extinction coefficient k, depend on the wavelength, and therefore, the optical constants for a wavelength of 525 nm shown in Table 5 were used for λ 1 and λ 2 of Example 2, the optical constants for a wavelength of 440 nm were used for λ 1 in Comparative Example 2, and the optical constants for a wavelength of 480 nm were used for λ 2 of Comparative Example 2 for calculation. Here, 525 nm, 440 nm and 480 nm were respectively estimated from the values of λ 1 and λ 2 , which were separately calculated. More precise calculation can be carried out through simulation using a computer. TABLE 4 λ 1 λ 2 Ex. 2 522 nm 516 nm Comp. 440 nm 478 nm Ex. 2 [0105] TABLE 5 n(Organic n(Ag) k(Ag) n(ITO) Layer) n(IZO) 525 nm 0.0528 3.09 2.04 1.82 2.04 480 nm 0.0522 2.51 2.06 1.84 2.06 440 nm 0.0559 2.32 2.09 1.89 2.09 [0106] In Example 2, when the center wavelength λ of the range wavelengths of white light for emission is 520 nm, λ 1 is 522 nm, and λ 2 is 516 nm, which is within the range of the present invention. [0107] FIG. 11 shows the results of simulation of the taking-out efficiency in a visible light range in Example 2. As shown in FIG. 11 , in the first interference, the taking-out efficiency in the green range in the vicinity of 520 nm is high, and in the second interference, the taking-out efficiency in blue and red is high. The total taking-out efficiency from this device is influenced by both of these two interferences, and as a result, is an taking-out efficiency which is approximately even throughout a wide visible light range. Accordingly, as shown in FIG. 13 , white light is emitted from the device of Example 2, and the chromaticity was (0.32, 0.42). The division of the spectra, shown in FIG. 13 , by the spectra of light emitted from the inside of the device becomes the actual taking-out efficiency. FIG. 14 shows the actual taking-out efficiency in Example 2. Here, as for the spectra of the internal luminescence, spectra that were gained from a device where the reflective layer does not contain Ag and the structure of other portions is the same were used. In the case where there is no reflective layer, the effects of interference are small, and the luminescence can be considered to be approximately equal to the internal luminescence. As shown in FIG. 14 , the effects of emission having a large width were gained in the actual experiment, in the same manner as in the simulation of FIG. 11 . [0108] In Comparative Example 2, when the center wavelength λ of the range of wavelengths of white light for emission is 520 nm, λ 1 is 440 nm and λ 2 is 478 nm. As is clear from the formula (4) and the formula (5), λ 1 and λ 2 are out of the range of the present invention, and therefore, it is clear that the organic EL device of Comparative Example 2 is out of the scope of the present invention. [0109] FIG. 12 is a graph showing the results of simulation of the taking-out efficiency in Comparative Example 2. As is clear from FIG. 12 , the total taking-out efficiency becomes higher in the short wavelength region. Accordingly, as shown in FIG. 13 , light having an intense blue component was emitted from this device of Comparative Example 2, and white light having good chromaticity was not gained. Here, the chromaticity was (0.18, 0.28). [0110] FIG. 14 shows the taking-out efficiency that was gained from the experiment of the device of Comparative Example 2. As is clear from FIG. 14 , Comparative Example 2 also provides spectra where the taking-out efficiency in the short wavelength region is high, in the same manner as the results of simulation shown in FIG. 12 . [0111] As described above, it can be seen that white light having good chromaticity can be gained according to the invention. [0112] FIG. 15 is a cross sectional diagram showing an organic EL display that is provided with the organic EL device according to an embodiment of the present invention. In this organic EL display, light emission in each pixel is driven using a TFT as an active device. Here, a diode or the like can also be used as an active device. In addition, a color filter is provided to this organic EL device. This organic EL display is a bottom emission type display which emits light to the underside of a substrate 1 for display, as shown by the arrow. [0113] In reference to FIG. 15 , a first insulating layer 2 is provided on top of the substrate 1 that is made of a translucent substrate, such as glass. The first insulating layer 2 is formed of, for example, SiO 2 and SiN x . A channel region 20 is formed of a polysilicon layer on top of the first insulating layer 2 . A drain electrode 21 and a source electrode 23 are formed on top of the channel region 20 , and in addition, a gate electrode 22 is provided between the drain electrode 21 and the source electrode 23 via a second insulating layer 3 . A fourth insulating layer 4 is provided on top of the gate electrode 22 . The second insulating layer 3 is formed of, for example, SiN x and SiO 2 , and the third insulating layer 4 is formed of SiO 2 and SiN x . [0114] A fourth insulating layer 5 is formed on top of the third insulating layer 4 . The fourth insulating layer 5 is formed of, for example, SiN x . A color filter layer 7 is provided in the portion of a pixel region on top of the fourth insulating layer 5 . A first flattened film 6 is provided on top of the color filter layer 7 . A through hole is formed in the first flattened film 6 above the drain electrode 21 , and a hole injection electrode 8 which is formed of ITO (indium-tin oxide) on top of the first flattened film 6 is introduced into the through hole. A hole injection layer 10 is formed on top of the hole injection electrode (anode) 8 in the pixel region. A second flattened film 9 is formed in portions other than the pixel region. [0115] A monochrome light-emitting device layer 11 according to the present invention is provided on top of the hole injection layer 10 . An electron transport layer 12 is provided on top of the light-emitting device layer 11 , and an electron injection electrode (cathode) 13 is provided on top of the electron transport layer 12 . [0116] As described above, the organic EL device of the present embodiment is formed in such a manner that a hole injection electrode (anode) 8 , a hole injection layer 10 , a light-emitting device layer 11 having the structure according to the present invention, an electron transport layer 12 and an electron injection electrode (cathode) 13 are laminated on top of a pixel region. [0117] Light of a predetermined color is emitted from the light-emitting device layer 11 . This light is emitted to the outside through the substrate 1 . On the side of light emission, a color filter layer 7 is provided. In the case where the light-emitting device layer 11 emits monochrome light, a color filter layer 7 of which the color tone is of the same type as the color of light emitted from the light-emitting device layer 11 is provided as the color filter layer 7 , and thereby, the color of the emitted light can be adjusted by means of the color filter layer 7 , and thus, the change in the color tone depending on the view angle can further be reduced, by providing the color filter layer 7 , because the color provided by the color filter layer 7 does not depend on the view angle. In the case where the light-emitting device layer 11 emits white light, a color filter such as R (red), G (green) or B (blue) is provided as the color filter layer 7 . [0118] FIG. 16 is a cross sectional diagram showing an organic EL display according to another embodiment of the present invention. The organic EL display of the present embodiment is a top emission type organic EL display which emits light upward from a substrate 1 for display, as illustrated by the arrow. [0119] The portions from the substrate 1 to the anode 8 are fabricated in approximately the same manner as in the embodiment shown in FIG. 15 . Here, the color filter layer 7 is not provided on top of the fourth insulating layer 5 , but rather, is placed above the organic EL device. Concretely, a color filter layer 7 is attached to a translucent sealing substrate 10 made of glass or the like, and an over-coating layer 15 is coated on top of this, and this is pasted to the top of the anode 8 via a translucent adhesive layer 14 , and thereby, the color filter layer 7 is attached. In addition, in the present embodiment, the position of the anode and the cathode is switched from that in the embodiment shown in FIG. 15 . [0120] As the anode 8 , a transparent electrode is formed by, for example, laminating ITO of which the film thickness is approximately 100 nm and silver of which the film thickness is approximately 20 nm. As for the cathode 13 , a reflective electrode is formed as, for example, a thin film of aluminum, chrome or silver having a film thickness of approximately 100 nm. The over-coating layer 15 is formed of an acryl resin or the like so as to have thickness of approximately 1 μm. The color filter layer 7 may be of a pigment type, or may be of a dye type. The thickness thereof is approximately 1 μm. [0121] Light of a predetermined color that has been emitted from the light-emitting device layer 11 is emitted to the outside through the sealing substrate 16 . On the emission side, a color filter layer 7 is provided, and as described above, the change in the color tone depending on the view angle can further be reduced. The organic EL display of the present embodiment is of the top emission type, and therefore, the regions where thin film transistors are provided can be used as pixel regions, and thus, the color filter layer 7 is provided in a range that is wider than that of the embodiment shown in FIG. 15 . The light-emitting device layer 11 is formed of an organic EL device according to the present invention, and is a light-emitting device layer having high efficiency of light emission, and a wider region can be used as a pixel region according to the present embodiment, and therefore, advantages of the light-emitting device layer having high efficiency of light emission can sufficiently be exploited. In addition, the formation of the light-emitting device layer having a number of luminous units can be carried out without taking the influence of the active matrix into consideration, and therefore, freedom of design can be increased. [0122] Though a glass plate is used as a sealing substrate in the above described embodiment, the sealing substrate is not limited to a glass plate according to the present invention, but rather, films, for example, oxide films, such as SiO 2 , and nitride films, such as SiN x , can also be used as the sealing substrate. In this case, a sealing substrate in film form can be formed directly on the device, and therefore, it becomes unnecessary to provide a translucent adhesive layer.
An electroluminescent device comprising: a luminous layer provided between a first electrode and a second electrode; and a reflective layer provided on the first electrode side for reflecting light emitted from the luminous layer and emitting the light from said second electrode side; wherein an optical distance L 1 between a light-emitting position of the luminous layer and the reflective layer is determined so as to allow the light with wavelength λ, which is center wavelength of the emitted light to be taken out, to increase in intensity as a result of interference, and wherein an optical distance L 2 between a reflective interface at the device end portion on the second electrode side and the reflective layer is determined so as to allow the light with wavelength λ to decrease in intensity as a result of interference.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "BACKGROUND OF THE INVENTION [0001] 1.", "Field of the Invention [0002] The present invention relates to an organic electroluminescent device, and in particular, to an organic electroluminescent device comprising a luminous layer provided between a first electrode and a second electrode, and a reflective layer provided on the first electrode side for reflecting light emitted from the luminous layer and emitting the light from the second electrode side.", "[0003] 2.", "Description of the Related Art [0004] Organic electroluminescent devices (organic EL devices) generally have a structure where an organic layer that includes a luminous layer having a thickness of approximately several tens of nm to several hundreds of nm is sandwiched between an electrode having reflecting properties and an electrode having translucence.", "In such organic EL devices, light that has been emitted from the luminous layer interferes in the device structure before being emitted to the outside.", "Conventionally, it has been attempted to use such interference to increase the luminous efficiency.", "[0005] Japanese Unexamined Patent Publication 2002-289358 proposes a technology where interference between light that has been emitted from a luminous layer in the direction toward an electrode having translucence and light that has been emitted in the direction toward an electrode having reflecting properties is used to increase the luminous efficiency by setting the distance between the light-emitting position and the reflective layer to such a distance that emitted light has such a wavelength as to resonate.", "[0006] In Japanese Unexamined Patent Publication 2000-243573, reflection from the interface between an electrode having translucence and a substrate is also taken into consideration, and the distance between the light-emitting position and an electrode having reflecting properties, and the distance between the light-emitting position and the interface between the electrode having translucence and the substrate are both defined.", "[0007] In the pamphlet of International PCT Patent Publication WO01/039554, interference caused by multiple reflection of light between an electrode having translucency and an electrode having reflecting properties is used to increase the luminous efficiency, by setting the film thickness between the electrode having translucence and the electrode having reflecting properties to such a thickness that light having a desired wavelength resonates.", "[0008] In all of the above described prior art technologies, interference of emitted light is used to increase the luminous efficiency.", "[0009] Meanwhile, there is a problem with light that has been emitted from an organic EL device, such that the color tone varies depending on the view angle.", "Conventionally, the use interference of emitted light in order to reduce such change in the color tone depending on the view angle has not been considered.", "[0010] In addition, interference as that described above occurs inside organic EL devices having a white luminous layer, and therefore, it is preferable for the light-emitting position to be in proximity to the reflective layer, preferably a distance of no greater than 80 nm, in order for white light having components of a wide range of wavelengths to be emitted efficiently.", "However, when the light-emitting position is at a distance from the reflective layer, making the distance between the two greater, it becomes difficult for white light having a wide range of spectra to be emitted by means of interference.", "[0011] Japanese Unexamined Patent Publication 2004-79421 discloses that the distance between the light-emitting position and a reflective layer, and the distance between the light-emitting position and the interface between an electrode having translucence and an external layer are defined, and thereby, an efficient device having excellent white chromaticity can be gained.", "SUMMARY OF THE INVENTION [0012] A first object of the present invention is to provide an organic EL device which can reduce the change in the color tone depending on the view angle.", "[0013] A second object of the present invention is to provide an organic EL device which can gain excellent white chromaticity.", "[0014] The present invention provides an organic electroluminescent device comprising: a luminous layer provided between a first electrode and a second electrode;", "and a reflective layer provided on the first electrode side for reflecting light emitted from the luminous layer and emitting the light from said second electrode side;", "wherein an optical distance L 1 between a light-emitting position of the luminous layer and the reflective layer is determined so as to allow the light with wavelength λ, which is center wavelength of the emitted light to be taken out, to increase in intensity as a result of interference, and wherein an optical distance L 2 between a reflective interface at the device end portion on the second electrode side and the reflective layer is determined so as to allow the light with wavelength λ to decrease in intensity as a result of interference.", "[0015] According to the present invention, the optical distance L 1 between the light-emitting position of the luminous layer and the reflective layer is an optical distance for allowing the light having the center wavelength λ to increase in intensity as a result of interference, and the optical distance L 2 between the reflective interface of the device end portion on the second electrode side and the reflective layer is an optical distance for allowing light having the wavelength λ to decrease in intensity as a result of interference.", "In the following, interference of light caused by the optical distance L 1 is referred to as “first interference,” and interference of light caused by the optical distance L 2 is referred to as “second interference.”", "[0016] The first interference and the second interference of the present invention are described in reference to FIG. 2 .", "[0017] In the organic EL device shown in FIG. 2 , a reflective layer 34 is formed on top of a substrate 37 , and a first electrode 31 is provided on top of the reflective layer 34 .", "An organic layer 38 that includes a luminous layer is provided on top of the first electrode 31 .", "In the present embodiment, the luminous layer in the organic layer 38 is formed by making a host material contain a dopant material.", "The position of light emission 33 a in the organic layer 38 generally differs depending on the carrier transportability of the host material in the luminous layer.", "According to the present invention, in the case where the host material of the luminous layer has electron transportability, the interface between the luminous layer and the hole transport layer becomes the light-emitting position 33 a. In addition, in the case where the host material of the luminous layer has hole transportability, the interface between the electron transport layer and the luminous layer becomes the light-emitting position 33 a. In the case where the luminous layer has both properties of electron transportability and hole transportability, so-called bipolar transportability, the center area in the direction of the thickness of the luminous layer becomes the light-emitting position 33 a. [0018] A second electrode 32 is provided on top of the organic layer 38 .", "In the present embodiment, the second electrode 32 is the top layer of the device, and there is a layer of air above the second electrode 32 .", "[0019] L 1 is the optical distance between the light-emitting position 33 a and the reflective layer 34 , and L 2 is the optical distance between the upper end portion 32 a of the second electrode 32 and the reflective layer 34 .", "The outside of the second electrode 32 is a layer of air, and reflection occurs from the interface between the second electrode 32 and the layer of air, due to the difference in the index of refraction between the second electrode 32 and the layer of air.", "Accordingly, the upper end portion 32 a of the second electrode 32 becomes the reflective interface of the device end portion.", "[0020] The first interference 40 occurs as interference between light 41 that is emitted from the light-emitting position 33 a toward the second electrode 32 side, and light 42 which is emitted from the light-emitting position 33 a toward the first electrode 31 side, and is reflected from the reflective layer 34 so as to be emitted to the second electrode 32 side.", "[0021] The second interference 50 is interference which occurs as a result of multiple reflection of light 51 that has been emitted from the light-emitting position 33 a, which is reflection of light from the interface 32 a between the second electrode 32 and the layer of air and reflection of light from the reflective layer 34 .", "[0022] The first interference 40 depends on the optical distance L 1 between the light-emitting position 33 a and the reflective layer 34 .", "In addition, the second interference 50 depends on the optical distance L 2 between the reflective interface 32 a of the device end portion and the reflective layer 34 .", "[0023] The efficiency of light emission from the device is influenced both by the above described first interference 40 and the second interference 50 .", "[0024] Here, in order to describe the change in the color tone depending on the view angle, which has conventionally been a problem, the first interference and the second interference are examined, taking the view angle into consideration.", "FIG. 3 is a diagram showing a view angle θ.", "As shown in FIG. 3 , in the case where the view angle is θ, the conditions for resonance between the first interference and the second interference can be represented by the following formulas (6) and (7).", "2 L 1 cos θ−λ φ 1 /2 π=m λ (6) 2 L 2 cos θ−λ(φ 1 +φ 2 )/2 π=m λ (7) [0025] Here, m is a natural number, including 0, L 1 is the optical distance between the light-emitting position and the reflective layer, L 2 is the optical distance between the reflective interface of the device end portion and the reflective layer, λ is a resonant wavelength, φ 1 is the phase shift when light is reflected from the reflective layer, and φ 2 is the phase shift when light is reflected from the reflective interface of the device end portion.", "[0026] As is clear from the above described formulas (6) and (7), the resonant wavelength between the first interference and the second interference shifts to the shorter wavelength side as the view angle θ increases.", "The taking-out efficiency is the sum of both effects;", "the first interference and the second interference, and this also shifts to the shorter wavelength side when the view angel increases.", "[0027] FIG. 4 is a graph illustrating a state where the wavelengths of light that is emitted from the device have shifted to the shorter wavelength side as the view angle increases.", "It can be seen in the spectrum A having a small half value width, as shown in FIG. 4 , that change in the color tone and brightness is greater when the view angle increases and the wavelengths shift to the shorter wavelength side.", "In contrast it can be seen in the spectrum B having a large half value width that change in the color tone and brightness is small even when the view angle increases and the wavelengths shift to the shorter wavelength side.", "The present invention provides a spectrum where the taking-out efficiency where the half value width is large in manner described above, and the peak of the spectrum is flat, and thereby, change in the color tone and brightness due to change in the view angle becomes small.", "In the following, how the present invention can provide taking-out efficiency where the half value width is large and the peak is flat in the manner described above is described.", "[0028] In the present invention, L 1 is an optical distance for allowing light having the wavelength λ to increase in intensity by means of interference.", "Accordingly, the first interference is interference for making light having the wavelength λ resonate.", "Meanwhile, L 2 is an optical distance for allowing light having the wavelength λ to decrease in intensity by means of interference.", "Therefore, the second interference makes light having the wavelength λ non-resonant, and is interference having respective resonant wavelengths on the shorter wavelength side and on the longer wavelength side of λ.", "The actual taking-out efficiency is affected both by the first interference and the second interference, and therefore, when these are added, the taking-out efficiency forms a flat spectrum having a large half value width.", "Accordingly, the present invention provides a flat spectrum for the taking-out efficiency having a large half value width, for example, the spectrum B shown in FIG. 4 .", "Accordingly, as described above, change in the color tone and brightness depending on the view angle can be reduced.", "[0029] According to the present invention, in the case where the luminous layer is a monochrome luminous layer, it is preferable for the optical distances L 1 and L 2 to satisfy the following formulas (1) to (5).", "2 L 1 −λ 1 φ 1 /2 π=mλ 1 (1) 2 L 2 −λ 2 (φ 1 +φ 2 )/2π=( n+ ½)λ 2 (2) λ f −30<λ<λ f +80 (3) λ−15<λ 1 <λ+15 (4) λ−15<λ 2 <λ+15 (5) [0030] (unit for λ: nm) [0031] Here, m and n are natural numbers, L 1 is the optical distance between the light-emitting position and the reflective layer, L 2 is the optical distance between the reflective interface of the device end portion and the reflective layer, λ f is the fluorescence peak wavelength of the luminous layer, φ 1 is the phase shift when light is reflected from the reflective layer, and φ 2 is the phase shift when light is reflected from the reflective interface of the device end portion.", "[0032] φ 1 can be represented by the following formula when the index of refraction of the first electrode is n e , the index of refraction of the reflective layer is n m , and the extinction coefficient of the reflective layer is k m .", "φ 1 =tan −1 {2 n e k m /( n e 2 −n m 2 −k m 2 )} [0033] Here, when 2n e k m /(n e 2 −n m 2 −k m 2 )>0, 0<φ 1 <π/2, and when 2n e k m /(n e 2 −n m 2 −k m 2 )<0, π/2<φ 1 <π.", "[0034] In addition, φ 2 is 0 when the index of refraction of the second electrode is greater than that of the layer outside of the device, and is π when the index of refraction of the second electrode is smaller than that of the layer outside of the device.", "[0035] In the above described formula (3), the lower limit value of λ is λ f −30, and the upper limit value of λ is λ f +80, where the upper limit value is wider because the fact that the spectrum of taking-out efficiency shifts to the shorter wavelength side when the view angle increases is taken into consideration.", "[0036] In the present invention, “monochrome”", "means a color other than white, and colors such as blue, green, red and orange can be cited as examples.", "[0037] According to the present invention, in the case where the luminous layer is a white light-emitting layer, it is preferable for the optical distances L 1 and L 2 to satisfy the following formulas (1) to (5).", "2 L 1 −λ 1 φ 1 /2 π=mλ 1 (1) 2 L 2 −λ 2 (φ 1 +φ 2 )/2π=( n+ ½)λ 2 (2) λ f −30<λ<λ f +80 (3) λ−15<λ 1 <λ+15 (4) λ−15<λ 2 <λ+15 (5) λ f −30<λ<λ f +80 (3) λ−15<λ 1 <λ+15 (4) λ−15<λ 2 <λ+15 (5) [0038] (unit for λ: nm) [0039] Here, m and n are natural numbers, L 1 is the optical distance between the light-emitting position and the reflective layer, L 2 is the optical distance between the reflective interface of the device end portion and the reflective layer, λ is the center wavelength in the range of wavelengths of white light for emission, φ 1 is the phase shift when light is reflected from the reflective layer, and φ 2 is the phase shift when light is reflected from the reflective interface of the device end portion.", "[0040] φ 1 can be represented by the following formula when the index of refraction of the first electrode is n e , the index of refraction of the reflective layer is n m , and the extinction coefficient of the reflective layer is k m .", "φ 1 =tan −1 {2 n e k m /( n e 2 −n m 2 −k m 2 )} [0041] Here, when 2n e k m /(n e 2 −n m 2 −k m 2 )>0, 0<φ 1 <π/2, and when 2n e k m /(n e 2 −n m 2 −k m 2 )<0, π/2<φ 1 <π.", "[0042] In addition, φ 2 is 0 when the index of refraction of the second electrode is greater than that of the layer outside of the device, and is π when the index of refraction of the second electrode is smaller than that of the layer outside of the device.", "[0043] In general, the second electrode is an electrode having translucence, and therefore, is formed of a thin layer of a conductive metal oxide or a metal thin film.", "Accordingly, in the case where the outside of the second electrode is a layer of air, a layer of resin or a layer of glass, the interface between the second electrode and this external layer becomes a reflective interface.", "On the other hand, in the case where an inorganic protective layer or the like is provided outside of the second electrode, the difference in the index of refraction between the second electrode and the inorganic protective layer is small, and therefore, in some cases, the outside of the second electrode does not become a reflective interface.", "In such a case, the outside of the inorganic protective layer becomes the reflective interface.", "[0044] According to the present invention, as described above, the light-emitting position from the luminous layer is the interface between the luminous layer and the layer that is adjacent to the luminous layer on the first electrode side (for example, the hole transport layer) in the case where the host material of the luminous layer has electron transportability, and is the interface between the luminous layer and the layer that is adjacent to the luminous layer on the second electrode side (for example, the electron transport layer) in the case where the host material of the luminous layer has hole transportability.", "[0045] According to the present invention, it is preferable for the thickness of the metal layer to be no greater than 5 nm in the case where a metal layer is provided between the organic layer that includes the luminous layer and the second electrode.", "The thickness of the metal layer is made to be no greater than 5 nm, and thereby, the effects of the reflection of light from this metal layer on the first interference and the second interference can be reduced.", "[0046] According to the present invention, it is preferable for the luminous layer to be formed of a host material and a dopant material.", "As the host material of the luminous layer, anthracene derivatives, aluminum complexes, rubrene derivatives, aryl amine derivatives and the like can be cited.", "According to the present invention, the luminous layer may be formed of two layers, where, for example, a blue light-emitting layer and an orange light-emitting layer are laminated, or may be formed of only one layer in the case where the luminous layer is a white light-emitting layer.", "[0047] As for the dopant material, a singlet luminous material may be used, or a triplet luminous material may be used.", "In order to gain high efficiency of light emission, it is preferable to use a triplet luminous material which is a phosphorescent material.", "As the singlet luminous material, perylene derivatives, coumarin derivatives, anthracene derivatives, tetracene derivatives, stilbene derivatives and the like can be cited.", "In addition, as the triplet luminous material (phosphorecent material), iridium complexes, platinum complexes and the like can be cited.", "[0048] According to the present invention, an organic layer other than the luminous layer may be provided.", "As the organic layer, carrier transport layers, such as hole transport layers and electron transport layers can be cited.", "As the material having hole transportability that is used for the hole transport layer, aryl amine derivatives and the like can be cited.", "In addition, as the material having electron transportability that is used for the electron transport layer, perylene derivatives, anthraquinone derivatives, anthracene derivatives, rubrene derivatives and the like can be cited.", "[0049] According to the present invention, the second electrode is generally formed of an electrode having translucence.", "As this electrode having translucence, translucent conductive metal oxide, such as ITO (indium tin oxide), IZO (indium zinc oxide) and tin oxide, can be cited.", "[0050] According to the present invention, the first electrode may be formed of an electrode having translucence, such as a conductive metal oxide, in the same manner as with the second electrode, or may be formed of a metal thin film or the like.", "In the case where the first electrode is formed of a metal thin film, it may also be used as the reflective layer according to the present invention.", "[0051] According to the present invention, the reflective layer is not particularly limited, as long as it can reflect light, and is generally formed of a metal thin film.", "As the metal thin film, Ag, Al, Mo, Cr and the like can be cited.", "Though the film thickness of the reflective layer is not particularly limited, it is generally preferable for it to be within a range from 100 nm to 300 nm.", "[0052] An organic electroluminescent display according to the present invention is provided with an organic electroluminescent device having a device structure that is sandwiched between an anode and a cathode, an active matrix driving substrate where active devices for supplying a display signal which corresponds to each display pixel to the organic electroluminescent device, and a translucent sealing substrate that is provided so as to face the active matrix driving substrate, which is a top emission type organic electroluminescent display where the organic electroluminescent device is placed between the active matrix driving substrate and the sealing substrate, and the electrode, which is either the cathode or the anode, and provided on the sealing substrate side is a translucent electrode, characterized in that the organic electroluminescent device is an organic electroluminescent device according to the above described present invention.", "[0053] A color filter of which the color tone is of the same type as the color of the emitted light may be placed between the sealing substrate and the organic electroluminescent device.", "A color filter of which the color tone is of the same type as the emitted light is used, and thereby, the change in the color tone depending on the view angle can further be reduced, and furthermore, a luminous display device of which the dependency on the view angle is small can be gained.", "[0054] The organic electroluminescent display according to the present invention is a top emission type display, and therefore, light that is emitted from the organic electroluminescent device is emitted from the sealing substrate on the side opposite to the side where the active matrix is provided.", "Generally, an active matrix circuit is formed by laminating a number of layers, and in the case of a bottom emission type, emitted light is attenuated due to the existence of this active matrix circuit, but the organic electroluminescent display according to the present invention is of a top emission type, and therefore, light can be emitted without being influenced by this active matrix circuit.", "In particular, the organic electroluminescent device according to the present invention has a number of luminous units, and the top emission type has fewer films through which emitted light transmits, in comparison with bottom emission types, and therefore, freedom of design for controlling attenuation of emitted light and narrowing of the view angle of emitted light by means of interference of light is increased.", "[0055] According to the present invention, the spectrum of the efficiency of light emission from the device can be made to be a flat spectrum having a large half value width.", "Accordingly, the change in the color tone depending on the view angle and the change in the brightness can be reduced, and thus, a luminous display of which the dependency on the view angle is small can be gained.", "[0056] In addition, in the case where the luminous layer is a white light-emitting layer, light can be emitted approximately evenly throughout the entirety of the wide range of wavelengths of white.", "Accordingly, emission of white light having excellent chromaticity can be gained.", "BRIEF DESCRIPTION OF THE DRAWINGS [0057] FIG. 1 is a schematic cross sectional diagram showing an organic EL device according to one embodiment of the present invention;", "[0058] FIG. 2 is a schematic cross sectional diagram illustrating the first interference and the second interference according to the present invention;", "[0059] FIG. 3 is a schematic diagram showing the view angle θ;", "[0060] FIG. 4 is a graph showing the change in spectrum of the taking-out efficiency depending on the view angle;", "[0061] FIG. 5 is a graph showing the results of simulation of the taking-out efficiency in an organic EL device according to Comparative Example 1;", "[0062] FIG. 6 is a graph showing the change in spectrum of emitted light depending on the view angle in the organic EL device according to Comparative Example 1;", "[0063] FIG. 7 is a graph showing the results of simulation of the taking-out efficiency in an organic EL device according to Example 1;", "[0064] FIG. 8 is a graph showing the change in spectrum of emitted light depending on the view angle in the organic EL device according to Example 1;", "[0065] FIG. 9 is a graph showing the actual taking-out efficiency in Example 1 and Comparative Example 1;", "[0066] FIG. 10 is a schematic cross sectional diagram showing an organic EL device according to another embodiment of the present invention;", "[0067] FIG. 11 is a graph showing the results of simulation of the taking-out efficiency in an organic EL device according to Example 2;", "[0068] FIG. 12 is a graph showing the results of simulation of the taking-out efficiency in an organic EL device according to Comparative Example 2;", "[0069] FIG. 13 is a graph showing the change in spectrum of emitted light in the organic EL devices of Example 2 and Comparative Example 2;", "[0070] FIG. 14 is a graph showing the actual taking-out efficiency in Example 2 and Comparative Example 2;", "[0071] FIG. 15 is a cross sectional diagram showing a bottom emission type organic EL display using an organic EL device according to an embodiment of the present invention;", "and [0072] FIG. 16 is a cross sectional diagram showing an organic EL display according to an embodiment of the present invention.", "DESCRIPTION OF PREFERRED EMBODIMENTS [0073] In the following, the embodiments of the present invention are more concretely described, but the present invention is not limited to these embodiments.", "EXAMPLE 1 [0074] An organic EL device having the device structure shown in FIG. 1 was fabricated.", "As shown in FIG. 1 , a reflective layer 34 (having a film thickness of 100 nm) was formed of Ag on top of a glass substrate 37 , a first electrode 31 (having a film thickness of 65 nm) was formed of ITO (indium tin oxide) on top of this, and a hole transport layer 35 (having a film thickness of 120 nm) was formed on top of this.", "[0075] A green light-emitting layer 33 (having a film thickness of 40 nm) was formed on top of the hole transport layer 35 , and an electron transport layer 36 (having a film thickness of 15 nm) was formed on top of this.", "A second electrode 32 was formed on top of the electron transport layer 36 .", "The second electrode 32 was formed of IZO (indium zinc oxide) (having a film thickness of 140 nm).", "An Li layer (having a film thickness of 0.3 nm) and an Au layer (having a film thickness of 1.5 nm) were formed as metal layers between the second electrode 32 and the electron transport layer 36 .", "Accordingly, an Li layer/Au layer/IZO layer was formed on top of the electron transport layer 36 .", "[0076] The green light-emitting layer was formed using TBADN as the host material, and 2 weight % of C545T was made to be contained as the dopant material.", "[0077] TBADN is 2-tertiary-butyl-9,10-di(2-naphthyl) anthracene, and has the following structure.", "C545T has the following structure.", "[0078] The hole transport layer 5 was formed of NPB.", "NPB is N, N′-di(naphthacene-1-yl)-N,N′-diphenyl benzidine, and has the following structure.", "[0079] The electron transport layer 6 was formed of BCP.", "BCP is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, and has the following structure.", "Comparative Example 1 [0080] An organic EL device according to Comparative Example 1 was fabricated in the same manner as in the above described Example 1, except that the film thickness of IZO was changed from 140 nm in the above described Example 1 to 70 nm.", "[0081] [Calculation of Resonant Wavelengths λ 1 and λ 2 ] [0082] The resonant wavelength λ 1 resulting from the first interference in Example 1 and Comparative Example 1, and resonant wavelength λ 2 resulting from the second interference were calculated using the formulas (1) and (2).", "The results of calculation are shown in Table 1.", "Here, the optical constants, such as the index of refraction n and the extinction coefficient k, are dependent on the wavelength, and therefore, the optical constants for a wavelength of 520 nm as shown in Table 2, were used for λ 1 and λ 2 of Example 1, the optical constants for a wavelength of 540 nm were used for λ 1 of Comparative Example 1, and the optical constants for a wavelength of 640 nm were used for λ 2 of Comparative Example 1 for calculation.", "Here, 520 nm, 540 nm and 640 nm were respectively estimated from the approximate values of λ 1 and λ 2 , which were separately calculated.", "More precise calculation can be carried out through simulation using a computer.", "[0083] The fluorescence peak wavelength λ f of the luminous layer was 500 nm.", "TABLE 1 λ 1 λ 2 Ex.", "1 531 nm 514 nm Comp.", "528 nm 621 nm Ex.", "1 [0084] TABLE 2 n(Organic n(Ag) k(Ag) n(ITO) Layer) n(IZO) 520 nm 0.0524 3.05 2.04 1.81 2.04 540 nm 0.0542 3.23 2.03 1.81 2.03 640 nm 0.066 4.11 1.97 1.78 1.97 [0085] In Comparative Example 1, the fluorescence peak wavelength λ f of the luminous layer was 500 nm, λ 1 was 528 nm, and λ 2 was 621 nm.", "As is clear from the above described formulas (3) and (5), λ 2 deviates from the range of the present invention, and it is clear that the organic EL device of Comparative Example 1 is out of the scope of the present invention.", "[0086] FIG. 5 is a graph showing the results of simulation of the taking-out efficiency in Comparative Example 1.", "As is clear from FIG. 5 , both the first interference and the second interference show a large taking-out efficiency in a green region, and as a result of this, the total taking-out efficiency forms a spectrum of the taking-out efficiency having a maximum in the vicinity of 520 nm, which is green, and a small half value width.", "As described above, the spectrum of this taking-out efficiency shifts to the shorter wavelength side when the view angle increases.", "FIG. 6 shows the spectrum of light emitted from this device at view angles of 0°, 30° and 60°.", "In Comparative Example 1, the half value width of the spectrum of the taking-out efficiency is small, and therefore, as shown in FIG. 6 , when the view angle increases, the color of the emitted light greatly changes.", "[0087] The actual taking-out efficiency is gained by dividing the spectra of FIG. 6 by the spectra of light emitted from the inside of the device, and the results are shown in FIG. 9 .", "Here, as for the spectra of the light emitted from the inside, spectra gained from an organic EL device where the reflective layer did not contain Ag and the structure of remaining portions was the same was used.", "In the case where there was no reflective layer, the effects of interference were small, and the luminescence can be considered to be approximately equal to the internal luminescence.", "[0088] It can be seen, as shown in FIG. 6 , that the actual taking-out efficiency in the comparative example is approximately equal to the simulation, and has a small half value width.", "[0089] In Example 1, the fluorescence peak wavelength λ f of the luminous layer is 500 nm, λ 1 is 531 nm, and λ 2 is 514 nm, which is within the range of the present invention.", "FIG. 7 is a graph showing the results of simulation of the taking-out efficiency in this example.", "As is clear from FIG. 7 , in the first interference, the taking-out efficiency in the green region is high, and in the second interference, the taking-out efficiency in blue and red is high.", "The total taking-out efficiency from this device is influenced by these two interferences, and a high taking-out efficiency can be gained throughout the entirety of a wide wavelength region, as shown in FIG. 7 .", "[0090] FIG. 8 is a graph showing spectra of light emitted from this device at a view angle of 0°, 30° and 60°.", "It can be seen, as is clear from FIG. 8 , that the color of emitted light barely changes depending on the view angle.", "The actual taking-out efficiency can be gained by dividing the spectrum at the view angle of 0° shown in FIG. 8 by the internal luminescence.", "[0091] FIG. 9 shows the actual taking-out efficiency in the example.", "It can be seen, as is clear from FIG. 9 , that, the taking-out efficiency from the device of the example is approximately constant throughout a wide range of wavelengths.", "Table 3 shows the color tone and the change in the brightness (the brightness is 100% when the view angle is 0°) of the organic EL devices of Example 1 and Comparative Example 1 at view angles of 0°, 30° and 60°.", "TABLE 3 View Angle 0° 30° 60° Ex.", "1 Chromaticity (0.256, 0.596) (0.267, 0.592) (0.228, 0.628) (x, y) Brightness % 100 100 85.3 Comp.", "Chromaticity (0.217, 0.696) (0.161, 0.679) (0.133, 0.535) Ex.", "1 (x, y) Brightness % 100 94.5 49.2 [0092] It can be seen, as is clear from the results shown in Table 3, that the change in the color tone and brightness depending on the view angle has been reduced in the organic EL device of Example 1 in comparison with Comparative Example 1.", "EXAMPLE 2 [0093] An organic EL device having the device structure shown in FIG. 10 was fabricated.", "As shown in FIG. 10 , a reflective layer 34 (having a film thickness of 100 nm) was formed of Ag on top of a glass substrate 37 , a first electrode 31 (having a film thickness of 65 nm) was formed of ITO (indium tin oxide) on top of this, and a hole transport layer 35 (having a film thickness of 100 nm) was formed on top of this.", "[0094] An orange light-emitting layer 33 c (having a film thickness of 15 nm) and a blue light-emitting layer 33 b (having a film thickness of 25 nm) were formed in this order on top of the hole transport layer 35 .", "A white light-emitting layer 33 was formed of the blue light-emitting layer 33 b and the orange light-emitting layer 33 c, and an electron transport layer 36 (having a film thickness of 10 nm) was formed on top of this white light-emitting layer 33 .", "A second electrode 32 was formed on top of the electron transport layer 36 .", "The second electrode 32 was formed of IZO (indium zinc oxide) (having a film thickness of 30 nm).", "An Li layer (having a film thickness of 0.3 nm) and an Au layer (having a film thickness of 1.5 nm) were formed as metal layers between the second electrode 32 and the electron transport layer 36 .", "Accordingly, an Li layer/Au layer/IZO layer was formed on top of the electron transport layer 36 .", "[0095] In the present example, the white light-emitting layer 33 is formed of a blue light-emitting layer 33 b and an orange light-emitting layer 33 c, and therefore, the interface between the blue light-emitting layer 33 b and the orange light-emitting layer 33 c becomes the light-emitting position 33 a. [0096] The orange light-emitting layer 33 c was formed using NPB as the host material, and 3 weight % of DBZR was made to be contained as a dopant material.", "[0097] DBzR is 5,12-bis{4-(6-methyl benzothiazole-2-yl) phenyl}-6,11-diphenyl naphthacene, and has the following structure.", "[0098] The blue light-emitting layer 33 b was formed using TBADN as the host material, and 2 weight % of TBP was made to be contained as a dopant material.", "[0099] TBP is 2,5,8,11-tetra-tertiary-butyl perylene, and has the following structure.", "[0100] The hole transport layer 35 is formed of NPB.", "[0101] The electron transport layer 36 is formed of BCP.", "Comparative Example 2 [0102] The organic EL device of Comparative Example 2 was fabricated in the same manner as in the above described Example 2, except that the film thickness of the hole transport layer 35 was made to be 45 nm, the film thickness of the orange light-emitting layer 33 c was made to be 30 nm, and the film thickness of the blue light-emitting layer was made to be 40 nm in the above described Example 2.", "[0103] [Calculation of Resonant Wavelengths λ 1 and λ 2 ] [0104] The resonant wavelength λ 1 resulting from the first interference and the resonant wavelength λ 2 resulting from the second interference in Example 2 and Comparative Example 2 were calculated using the formulas (1) and (2).", "The results of calculation are shown in Table 4.", "Here, the optical constants, such as the index of refraction n and the extinction coefficient k, depend on the wavelength, and therefore, the optical constants for a wavelength of 525 nm shown in Table 5 were used for λ 1 and λ 2 of Example 2, the optical constants for a wavelength of 440 nm were used for λ 1 in Comparative Example 2, and the optical constants for a wavelength of 480 nm were used for λ 2 of Comparative Example 2 for calculation.", "Here, 525 nm, 440 nm and 480 nm were respectively estimated from the values of λ 1 and λ 2 , which were separately calculated.", "More precise calculation can be carried out through simulation using a computer.", "TABLE 4 λ 1 λ 2 Ex.", "2 522 nm 516 nm Comp.", "440 nm 478 nm Ex.", "2 [0105] TABLE 5 n(Organic n(Ag) k(Ag) n(ITO) Layer) n(IZO) 525 nm 0.0528 3.09 2.04 1.82 2.04 480 nm 0.0522 2.51 2.06 1.84 2.06 440 nm 0.0559 2.32 2.09 1.89 2.09 [0106] In Example 2, when the center wavelength λ of the range wavelengths of white light for emission is 520 nm, λ 1 is 522 nm, and λ 2 is 516 nm, which is within the range of the present invention.", "[0107] FIG. 11 shows the results of simulation of the taking-out efficiency in a visible light range in Example 2.", "As shown in FIG. 11 , in the first interference, the taking-out efficiency in the green range in the vicinity of 520 nm is high, and in the second interference, the taking-out efficiency in blue and red is high.", "The total taking-out efficiency from this device is influenced by both of these two interferences, and as a result, is an taking-out efficiency which is approximately even throughout a wide visible light range.", "Accordingly, as shown in FIG. 13 , white light is emitted from the device of Example 2, and the chromaticity was (0.32, 0.42).", "The division of the spectra, shown in FIG. 13 , by the spectra of light emitted from the inside of the device becomes the actual taking-out efficiency.", "FIG. 14 shows the actual taking-out efficiency in Example 2.", "Here, as for the spectra of the internal luminescence, spectra that were gained from a device where the reflective layer does not contain Ag and the structure of other portions is the same were used.", "In the case where there is no reflective layer, the effects of interference are small, and the luminescence can be considered to be approximately equal to the internal luminescence.", "As shown in FIG. 14 , the effects of emission having a large width were gained in the actual experiment, in the same manner as in the simulation of FIG. 11 .", "[0108] In Comparative Example 2, when the center wavelength λ of the range of wavelengths of white light for emission is 520 nm, λ 1 is 440 nm and λ 2 is 478 nm.", "As is clear from the formula (4) and the formula (5), λ 1 and λ 2 are out of the range of the present invention, and therefore, it is clear that the organic EL device of Comparative Example 2 is out of the scope of the present invention.", "[0109] FIG. 12 is a graph showing the results of simulation of the taking-out efficiency in Comparative Example 2.", "As is clear from FIG. 12 , the total taking-out efficiency becomes higher in the short wavelength region.", "Accordingly, as shown in FIG. 13 , light having an intense blue component was emitted from this device of Comparative Example 2, and white light having good chromaticity was not gained.", "Here, the chromaticity was (0.18, 0.28).", "[0110] FIG. 14 shows the taking-out efficiency that was gained from the experiment of the device of Comparative Example 2.", "As is clear from FIG. 14 , Comparative Example 2 also provides spectra where the taking-out efficiency in the short wavelength region is high, in the same manner as the results of simulation shown in FIG. 12 .", "[0111] As described above, it can be seen that white light having good chromaticity can be gained according to the invention.", "[0112] FIG. 15 is a cross sectional diagram showing an organic EL display that is provided with the organic EL device according to an embodiment of the present invention.", "In this organic EL display, light emission in each pixel is driven using a TFT as an active device.", "Here, a diode or the like can also be used as an active device.", "In addition, a color filter is provided to this organic EL device.", "This organic EL display is a bottom emission type display which emits light to the underside of a substrate 1 for display, as shown by the arrow.", "[0113] In reference to FIG. 15 , a first insulating layer 2 is provided on top of the substrate 1 that is made of a translucent substrate, such as glass.", "The first insulating layer 2 is formed of, for example, SiO 2 and SiN x .", "A channel region 20 is formed of a polysilicon layer on top of the first insulating layer 2 .", "A drain electrode 21 and a source electrode 23 are formed on top of the channel region 20 , and in addition, a gate electrode 22 is provided between the drain electrode 21 and the source electrode 23 via a second insulating layer 3 .", "A fourth insulating layer 4 is provided on top of the gate electrode 22 .", "The second insulating layer 3 is formed of, for example, SiN x and SiO 2 , and the third insulating layer 4 is formed of SiO 2 and SiN x .", "[0114] A fourth insulating layer 5 is formed on top of the third insulating layer 4 .", "The fourth insulating layer 5 is formed of, for example, SiN x .", "A color filter layer 7 is provided in the portion of a pixel region on top of the fourth insulating layer 5 .", "A first flattened film 6 is provided on top of the color filter layer 7 .", "A through hole is formed in the first flattened film 6 above the drain electrode 21 , and a hole injection electrode 8 which is formed of ITO (indium-tin oxide) on top of the first flattened film 6 is introduced into the through hole.", "A hole injection layer 10 is formed on top of the hole injection electrode (anode) 8 in the pixel region.", "A second flattened film 9 is formed in portions other than the pixel region.", "[0115] A monochrome light-emitting device layer 11 according to the present invention is provided on top of the hole injection layer 10 .", "An electron transport layer 12 is provided on top of the light-emitting device layer 11 , and an electron injection electrode (cathode) 13 is provided on top of the electron transport layer 12 .", "[0116] As described above, the organic EL device of the present embodiment is formed in such a manner that a hole injection electrode (anode) 8 , a hole injection layer 10 , a light-emitting device layer 11 having the structure according to the present invention, an electron transport layer 12 and an electron injection electrode (cathode) 13 are laminated on top of a pixel region.", "[0117] Light of a predetermined color is emitted from the light-emitting device layer 11 .", "This light is emitted to the outside through the substrate 1 .", "On the side of light emission, a color filter layer 7 is provided.", "In the case where the light-emitting device layer 11 emits monochrome light, a color filter layer 7 of which the color tone is of the same type as the color of light emitted from the light-emitting device layer 11 is provided as the color filter layer 7 , and thereby, the color of the emitted light can be adjusted by means of the color filter layer 7 , and thus, the change in the color tone depending on the view angle can further be reduced, by providing the color filter layer 7 , because the color provided by the color filter layer 7 does not depend on the view angle.", "In the case where the light-emitting device layer 11 emits white light, a color filter such as R (red), G (green) or B (blue) is provided as the color filter layer 7 .", "[0118] FIG. 16 is a cross sectional diagram showing an organic EL display according to another embodiment of the present invention.", "The organic EL display of the present embodiment is a top emission type organic EL display which emits light upward from a substrate 1 for display, as illustrated by the arrow.", "[0119] The portions from the substrate 1 to the anode 8 are fabricated in approximately the same manner as in the embodiment shown in FIG. 15 .", "Here, the color filter layer 7 is not provided on top of the fourth insulating layer 5 , but rather, is placed above the organic EL device.", "Concretely, a color filter layer 7 is attached to a translucent sealing substrate 10 made of glass or the like, and an over-coating layer 15 is coated on top of this, and this is pasted to the top of the anode 8 via a translucent adhesive layer 14 , and thereby, the color filter layer 7 is attached.", "In addition, in the present embodiment, the position of the anode and the cathode is switched from that in the embodiment shown in FIG. 15 .", "[0120] As the anode 8 , a transparent electrode is formed by, for example, laminating ITO of which the film thickness is approximately 100 nm and silver of which the film thickness is approximately 20 nm.", "As for the cathode 13 , a reflective electrode is formed as, for example, a thin film of aluminum, chrome or silver having a film thickness of approximately 100 nm.", "The over-coating layer 15 is formed of an acryl resin or the like so as to have thickness of approximately 1 μm.", "The color filter layer 7 may be of a pigment type, or may be of a dye type.", "The thickness thereof is approximately 1 μm.", "[0121] Light of a predetermined color that has been emitted from the light-emitting device layer 11 is emitted to the outside through the sealing substrate 16 .", "On the emission side, a color filter layer 7 is provided, and as described above, the change in the color tone depending on the view angle can further be reduced.", "The organic EL display of the present embodiment is of the top emission type, and therefore, the regions where thin film transistors are provided can be used as pixel regions, and thus, the color filter layer 7 is provided in a range that is wider than that of the embodiment shown in FIG. 15 .", "The light-emitting device layer 11 is formed of an organic EL device according to the present invention, and is a light-emitting device layer having high efficiency of light emission, and a wider region can be used as a pixel region according to the present embodiment, and therefore, advantages of the light-emitting device layer having high efficiency of light emission can sufficiently be exploited.", "In addition, the formation of the light-emitting device layer having a number of luminous units can be carried out without taking the influence of the active matrix into consideration, and therefore, freedom of design can be increased.", "[0122] Though a glass plate is used as a sealing substrate in the above described embodiment, the sealing substrate is not limited to a glass plate according to the present invention, but rather, films, for example, oxide films, such as SiO 2 , and nitride films, such as SiN x , can also be used as the sealing substrate.", "In this case, a sealing substrate in film form can be formed directly on the device, and therefore, it becomes unnecessary to provide a translucent adhesive layer." ]
TECHNICAL FIELD This invention relates to molecular sieves and, more particularly, to yttrium silicate molecular sieves. BACKGROUND OF THE INVENTION The term "molecular sieve" refers to a wide variety of positive ion containing crystalline materials of both natural and synthetic varieties which exhibit the property of acting as sieves on a molecular scale. A major class of molecular sieves are crystalline aluminosilicates, although other crystalline materials are included in the broad definition. Examples of such other crystalline materials include coal, special active carbons, porous glass, microporous beryllium oxide powders, and layer silicates modified by exchange with organic cations. See, D. W. Breck, "Zeolite Molecular Sieves: Structure, Chemistry, and Use", John Wiley & Sons, 1974. Zeolites are crystalline, hydrated, framework aluminosilicates which are based on a three-dimensional network of AlO 4 and SiO 4 tetrahedra linked to each other by sharing all of the oxygens. Zeolites may be represented by the empirical formula M.sub.2/n O.Al.sub.2 O.sub.3.xSiO.sub.2.yH.sub.2 O wherein, x is generally equal to or greater than 2 since AlO 4 tetrahedra are joined only to SiO 4 tetrahedra, and n is the cation valence. The framework contains channels and interconnected voids which are occupied by the cation, M, and water molecules. The cations may be mobile and exchangeable to varying degrees by other cations. Intracrystalline zeolitic water in many zeolites is removed continuously and reversibly. In many other zeolites, mineral and synthetic, cation exchange or dehydration may produce structural changes in the framework. Ammonium and alkylammonium cations may be incorporated in synthetic zeolites, e.g., NH 4 , CH 3 NH 3 , (CH 3 ) 2 NH 2 , (CH 3 ) 3 NH, and (CH 3 ) 4 N. In some synthetic zeolites, aluminum cations may be substituted by gallium ions and silicon ions by germanium or phosphorus ions. The latter necessitates a modification of the structural formula. The structural formula of a zeolite is best expressed for the crystallographic unit cell as: M x/n [(AlO 2 ) x (SiO 2 ) y ].wH 2 O where M is the cation of valence n, w is the number of water molecules and the ratio y/x usually has values of 1-100 depending upon the structure. The sum (x+y) is the total number of tetrahedra in the unit cell. The complex within the [] represents the framework composition. The zeolites described in the patent literature and published journals are designated by letters or other convenient symbols. Exemplary of these materials are Zeolite A (U.S. Pat. No. 2,882,243), Zeolite X (U.S. Pat. No. 2,882,244), Zeolite Y (U.S. Pat. No. 3,130,007), Zeolite ZSM-5 (U.S. Pat. No. 3,702,886), Zeolite ZSM-11 (U.S. Pat. No. 3,708,979), and Zeolite ZSM-12 (U.S. Pat. No. 3,832,449). Although there are 34 species of zeolite minerals and about 100 types of synthetic zeolites, only a few have been found to have practical significance. Many of the zeolites, after dehydration, ae permeated by very small channel systems which are not interpenetrating and which may contain serious diffusion blocks. In other cases dehydration irreversibly disturbs the framework structure and the positions of metal cations, so that the structure partially collapses and dehydration is not completely reversible. To be efficiently used as a molecular sieve, the structure of the zeolite after complete dehydration must remain intact. There has been considerable interest in developing metallosilicates other than aluminosilicates which exhibit molecular sieve characteristics. For example, U.S. Pat. Nos. 3,329,480 and 3,329,481 disclose crystalline zircano-silicates and titano-silicates, respectively. U.S. Pat. No. 3,329,384 discloses Group IV-B metallosilicates. U.S. Pat. Nos. 4,208,305, 4,238,315 and 4,337,176 disclose iron silicates. U.S. Pat. No. 4,329,328 discloses zinco-, stanno-, and titano-silicates. European patent application Nos. 0 038 682 and 0 044 740 disclose cobalt silicates. European Patent Application No. 0 050 525 discloses nickel silicate. U.K. Patent Application No. GB 2,024,790 A discloses a silica-based material which has been modified with one or more elements which have entered the crystalline lattice of the silica in place of silicon atoms of the silica or in the form of salts of bisilicic or polysilicic acids. The elements identified as being suitable for making such silica-based materials are chromium, beryllium, titanium, vanadium, manganese, iron, cobalt, zinc, zirconium, rhodium, silver, tin, antimony and boron. U.S. Pat. No. 4,299,808 discloses chromosilicates formed by reacting an aqueous mixture of an oxide of silicon, a compound of chromium, a hydroxide of an alkali or an alkaline earth metal, and an alkylammonium cation or a precursor of an alkylammonium cation. U.S. Pat. Nos. 4,192,778 and 4,339,354 relate to a rare earth metal containing silicates. The former patent discloses rare earth exchanged zeolites of the faujasite type in which the equivalent of Na is less than 0.1 and the rare earth is at least 0.9 equivalents per gram atom of aluminum. The latter patent discloses a catalyst comprising a crystalline aluminosilicate such as zeolite Y, an inorganic matrix, and discrete particles of alumina, the catalyst having specified alkali metal and rare earth metal contents. U.S. Pat. No. 3,769,386 discloses zeolitic alumino-metallosilicates crystallized from an aqueous reaction mixture containing Na 2 O, SiO 2 , Al 2 O 3 and R 2/n wherein R is Mg, Ca, Y, Fe, Co, Ni or a rare earth metal and n is the valence of R. There remains a need for suitable metallosilicates that exhibit molecular sieve character, are stable at temperatures in excess of about 400° C., have relatively uniform pore sizes and are capable of desorbing an adsorbed phase without significant change in crystal structure. There is also a need for a relatively simplified method for making such metallosilicates. SUMMARY OF THE INVENTION The present invention relates to yttrium silicates which exhibit molecular sieve character, are stable at temperatures in excess of about 400° C., have relatively uniform pore sizes, and are capable of desorbing an adsorbed phase without significant change in crystal structure. The invention also relates to a relatively simplified method for making such yttrium silicates. Broadly stated, the present invention contemplates the provision of a molecular sieve comprising a complex represented in terms of mole ratios of oxides as follows: aA.sub.2 O:Y.sub.2 O.sub.3 :bSiO.sub.2 :cH.sub.2 O wherein A is an alkali metal; a is a number ranging from about 0.5 to about 20; b is a number ranging from about 2 to about 400; and c is a number ranging from about 1 to about 500. The invention further provides for a method for preparing a molecular sieving yttrium silicate comprising maintaining a mixture of a source of silicon, a source of yttrium, a source of alkali metal and water at a temperature in the range of about 50° C. to about 350° C. for an effective period of time to provide said yttrium silicate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The molecular sieving yttrium silicates provided in accordance with the invention are complexes represented in terms of mole ratios of oxides by the formula aA.sub.2 O:Y.sub.2 O.sub.3 :bSiO.sub.2 :cH.sub.2 O wherein A is an alkali metal, preferably sodium, a is a number ranging from about 0.5 to about 20, preferably from about 0.8 to about 10; b is a number ranging from about 2 to about 400, preferably from about 3 to about 200; and c is a number ranging from about 1 to about 500, preferably from about 1 to about 200. These yttrium silicates exhibit two different general structures. One of the structures exhibits the following significant distinguishing lines among the reflections in the x-ray diffraction pattern, and is a preferred material formed when the Si/Y ratio is less than about six in the recovered solid. TABLE I______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.30 ± 0.40 s6.22 ± 0.15 s5.54 ± 0.15 w-m3.55 ± 0.08 w3.09 ± 0.06 s2.99 ± 0.05 s2.83 ± 0.04 w2.76 ± 0.03 w-m2.41 ± 0.03 w2.22 ± 0.03 w2.17 ± 0.02 w2.01 ± 0.02 w______________________________________ The other structure generally forms when the Si/Y ratio in the recovered solid is greater than about six. This material exhibits at least the following distinguishing lines among the reflections in its x-ray diffraction pattern: TABLE II______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.30 ± 0.50 m7.06 ± 0.15 vs6.57 ± 0.15 m6.08 ± 0.15 w5.83 ± 0.10 w4.80 ± 0.10 m4.48 ± 0.08 m3.74 ± 0.08 w3.48 ± 0.06 w3.09 ± 0.05 m2.99 ± 0.05 m-s2.90 ± 0.04 w-m2.73 ± 0.04 m2.16 ± 0.03 w______________________________________ These general patterns of significant x-ray reflections can also be attributed to the calcined and ion exchange forms of the yttrium silicates, although minor line shifts usually occur in the materials when these processes are performed. The values were determined by standard techniques. The relative intensities are given in terms of symbols: vs=very strong; s=strong; m=medium; w=weak; and vw=very weak. All x-ray patterns are obtained using standard x-ray powder diffraction techniques. The radiation source is a standard intensity, copper target, x-ray tube operated at 40 Kv and 20 ma. The diffraction pattern from the K alpha radiation is suitably recorded by an x-ray spectrometer scintillation counter, plus height analyzer and strip chart recorder. Flat compressed powder samples are scanned at 1° per minute, using a two second time constant. Interplanar spacings (d) are obtained from the position if the diffraction peaks expressed as 2θ where θ is the Bragg angle as observed on the strip chart. Intensities are determined from the heights of diffraction peaks after subtracting background. As will be understood by those skilled in the art, the determination of the parameter 2θ, irrespective of the technique employed, is subject to both human and mechanical error, which in combination, can improve an uncertainty of about 0.4° on each reported value of 2θ. This uncertainty is, of course, also manifested in the reported values of the d-spacings, which are calculated from the 2θ values. This impression is general throughout the art and is not sufficient to preclude the differentiation of the present crystalline materials from each other and from the compositions of the prior art. In a preferred embodiment of the invention, the mixture provided for in the process of the invention for making the yttrium silicates is preferably prepared in three steps. First, the silicon source is mixed in water to provide a first mixture. This first mixture is preferably in the form of a colloidal dispersion. Second, the yttrium source is mixed with water to provide a second mixture. This second mixture is usually in the form of a dispersion or solution. Third, these first and second mixtures are mixed together to form a gel. The source of alkali metal is added to the gel with stirring. The Si to yttrium mole ratio is preferably in the range of about 1 to about 200, more preferably about 2 to about 30. The OH-- to Y mole ratio is preferably in the range of about 1 to about 25. The H 2 O to Y mole ratio is preferably in the range of about 50 to about 2500. The alkali metal to Y mole ratio is preferably in the range of about 1 to about 25, more preferably about 3 to about 20. The silicon source can be any source that provides silicon oxide, hydroxide or alkoxide. Such sources include silica gel, silicic acid, silica sol and the silicates. Included within the silicates are the alkali and alkaline earth metal silicates with sodium silicate and potassium silicate being preferred. The alkoxides include those alkoxides of up to about 10, preferably up to about 6 carbon atoms. The silica sols are aqueous colloidal dispersions containing colloidal silica particles. The solids content of these colloidal dispersions generally ranges up to about 70% by weight, and is preferably in the range of about 5% to about 50%. These dispersions usually include an effective amount of an anionic (e.g., acetate, halogen, etc.) or cationic (e.g., alkali metal, ammonium, etc.) stabilizing agent to stabilize the dispersion. Generally the level of addition of such stabilizing agents is up to about 10% by weight of the solids in the dispersion. A commercially available silica sol that is particularly useful is Ludox AS-30 which is a product of DuPont identified as an ammonium stabilized silica sol containing 30% by weight silica. The yttrium source can be any compound that provides trivalent yttrium. These compounds include oxides, hydroxides, inorganic salts (e.g., nitrates, sulfates, halides, carbonates, silicates, and the like) as well as the organic salts, (e.g., acetates, formates, butyrates, propionates, benzylates and the like). Yttrium chloride, yttrium chloride hydrate, and yttrium oxide are preferred. The alkali metal source can be any metal compound that provides the desired alkali metal cation. These compounds include the oxides, hydroxides, inorganic salts (e.g., nitrates, halides, sulfates, carbonates, silicates, and the like) as well as the organic salts, (e.g., acetates, formates, butyrates, propionates, benzylates and the like). Sodium hydroxide is preferred. In the method of the present invention for making the yttrium silicates, the mixture containing water, the source of silicon, the yttrium source, and the alkali metal source is preferably thoroughly mixed and then placed in a reactor. The reactor is preferably an enclosed reactor (e.g., a static bomb style reactor). The contents are heated to a temperature in the range of preferably about 50° C. to about 350° C., more preferably about 100° C. to about 200° C., under autogeneous pressure for an effective period of time to provide the desired molecular sieving yttrium silicate, preferably for about one hour to about 30 days, more preferably about 6 hours to about 14 days. The contents of the reactor are then allowed to cool to room temperature. The crystalline solids are separated from the mother liquor and washed thoroughly with water. Separation can be effected by conventional filtration techniques. The crystalline solids are then allowed to dry in air, such solids being the desired molecular sieving yttrium silicates of the invention. The yttrium silicates of the invention can be ion exchanged with an ammonium salt or a salt of a catalytically active metal. The salt of the catalytically active metal is preferably the salt of a Group VIII, IB or IIB metal, with zinc, copper, nickel, cobalt and iron being preferred. The anionic portions of these salts include the nitrates, phosphates, sulfates, acetates and halides. The cation exchange procedure employed herein is entirely conventional. Briefly, the yttrium silicate and the ammonium salt or salt of catalytically active metal are dispersed in water for an effective period of time and at a sufficient temperature to provide the desired ion-exchanged yttrium silicate. Preferably the yttrium silicate and the salt are so dispersed for a few minutes to several hours, preferably about one to about ten hours, and maintained at about room temperature to about the boiling point of the water. The ion-exchanged yttrium silicate is then filtered and washed. Optionally, the ion-exchanged yttrium silicates can be heat treated in an inert, oxidizing or reducing atmosphere using the following heat treating procedures to convert the ion-exchanged species to a more active form. The heat treating procedure is conducted at a temperature of about 200° C. to about 900° C., preferably about 300° C. to about 600° C. The time period for this heat treating step is dependent upon the mass of material being treated. Preferably the heat treating step is conducted for at least about 30 minutes, but this time period can be more or less than 30 minutes depending upon the mass of material being treated. The inert atmosphere is preferably nitrogen, argon, helium or neon. The reducing atmosphere is hydrogen or a mixture of hydrogen and one of the above-indicated insert gases. The reducing atmosphere can contain from about 1% to about 100% hydrogen, preferably about 1% to about 20% hydrogen, with the remainder being inert gas. The oxidizing atmosphere can be oxygen or a mixture of oxygen and one of the above-indicated inert gases. The oxidizing atmosphere can contain from about 1% to about 100% oxygen, preferably from about 1% to about 20% oxygen with the remainder being inert as. A preferred oxidizing atmosphere is air. In order to further illustrate the present invention, the following examples are provided. Unless otherwise indicated, in the following examples as well as throughout the specification and in the claims, all parts and percentages are by weight, and all temperatures are in degrees centrigrade. EXAMPLE 1 0.985 grams of yttrium chloride hydrate were dissolved in 2 grams of water. This solution was mixed with 1.3 grams of Ludox AS-30 and stirred. 1.5 grams of a 50% sodium hydroxide solution diluted in 2 grams of water were added to the mixture. The mixture was stirred until a uniform gel was formed. The Si/Y mole ratio was about 2. The Na/Y mole ratio was about 5.9. The H 2 O/Y mole ratio was about 70. The mixture was charged to a Teflon lined static bomb reactor. The reactor was placed in an oven at 170° C. for 12 days. The reactor was removed from the oven and cooled. The product was removed from the reactor, filtered, washed with distilled water and dried. Elemental analysis and the determination of the loss on ignition (LOI) to 1000° C. for the recovered solid resulted in the following formulation on an oxide basis: 0.9Na.sub.2 O:Y.sub.2 O.sub.3 :3.1SiO.sub.2 :2.6H.sub.2 O The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.42 s9.56 w6.22 m5.82 w5.64 w4.79 w3.76 w3.55 w3.09 s3.08 s2.99 s2.88 w2.82 m2.76 w2.69 w2.41 w2.26 w2.22 w2.06 w2.01 w______________________________________ EXAMPLE 2 0.492 grams of yttrium chloride hydrate were dissolved in 2 grams of water. This solution was mixed with 1.3 grams of Ludox AS-30 and stirred. 1.5 grams of a 50% sodium hydroxide solution diluted in 2 grams of water were added to the mixture. The mixture was stirred until a uniform gel was formed. The Si/Y mole ratio was about 4. The Na/Y mole ratio was about 11.6. The H 2 O/Y mole ratio was about 132. The mixture was charged to a Teflon lined static bomb reactor. The reactor was placed in an oven at 170° C. for 12 days. The reactor was removed from the oven and cooled. The product was removed from the reactor, filtered, washed with distilled water and dried. Elemental analysis and the determination of the LOI to 1000° C. for the recovered solid resulted in the following formulation on an oxide basis: 1.4Na.sub.2 O:Y.sub.2 O.sub.3 :4.7SiO.sub.2 :3.6H.sub.2 O The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.34 vs6.20 s5.54 w4.80 w3.52 w3.09 s2.99 s2.84 m2.76 m2.41 w2.23 w2.16 w2.06 w2.01 w______________________________________ EXAMPLE 3 9.75 grams of yttrium chloride hydrate were dissolved in 450 grams of water to provide a first mixture. 97.5 grams of Ludox AS-30 were diluted with 525 grams of water to provide a second mixture. The first and second mixtures were mixed together and stirred. 45 grams of a 50% sodium hydroxide solution diluted in 225 grams of water were added to the mixture. The mixture was stirred until a uniform gel was formed. The Si/Y mole ratio was about 15.2. The Na/Y mole ratio was about 17.5. The H 2 O/Y mole ratio was about 2050. The mixture was charged to a Teflon lined static bomb reactor. The reactor was placed in an oven at 170° C. for 4 days. The reactor was removed from the oven and cooled. The product was removed from the reactor, filtered, washed with distilled water and dried. Elemental analysis and the determination of the LOI to 1000° C. for the recovered solid resulted in the following formulation on an oxide basis: 2.7Na.sub.2 O:Y.sub.2 O.sub.3 :14.8SiO.sub.2 :10.1H.sub.2 O The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.38 m7.07 vs6.60 m6.08 w5.83 w4.80 m4.48 m3.74 w3.50 w3.40 m3.10 m3.00 m2.90 w2.74 m2.64 w2.56 w2.34 w2.15 w______________________________________ EXAMPLE 4 0.492 grams of yttrium chloride hydrate were dissolved in one gram of water. This solution was mixed with 1.3 grams of Ludox AS-30 and stirred. One gram of a 50% sodium hydroxide solution diluted in one gram of water was added to the mixture. The mixture was stirred until a uniform gel was formed. The Si/Y mole ratio was about 4. The Na/Y mole ratio was about 7.7. The H 2 O/Y mole ratio was about 65. The mixture was charged to a Teflon lined static bomb reactor. The reactor was placed in an oven at 170° C. for 4 days. The reactor was removed from the oven and cooled. The product was removed from the reactor, filtered, washed with distilled water and dried. The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation ) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.40 s9.64 w6.19 m5.63 w3.58 m3.09 s3.08 s2.98 s2.88 s2.83 m2.75 m2.68 w2.41 w2.27 w2.22 w2.18 w2.10 w2.02 w______________________________________ EXAMPLE 5 0.06 grams of yttrium chloride hydrate were dissolved in 3.75 grams of water. This solution was mixted with 3.9 grams of Ludox AS-30 and stirred. 1.5 grams of a 50% sodium hydroxide solution diluted in 3.75 grams of water were added to the mixture. The mixture was stirred until a uniform gel was formed. The Si/Y mole ratio was about 98. The Na/Y mole ratio was about 95. The H 2 O/Y mole ratio was about 2100. The mixture was charged to a Teflon lined static bomb reactor. The reactor was placed in an oven at 170° C. for 5 days. The reactor was removed from the oven and cooled. The product was removed from the reactor, filtered, washed with distilled water and dried. The x-ray diffraction pattern of this dired product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.60 m7.01 s6.57 m5.85 w5.63 w4.77 w4.48 w3.69 w3.46 w3.09 w2.98 s2.73 w2.15 w______________________________________ EXAMPLE 6 Ion-exchanged yttrium silicates were prepared by placing 0.5 gram of the product of Example 3 in each of three flasks containing 20 ml of 0.1M solutions of NH 4 Cl, KCl, and CaCl 2 , respectively. The mixtures were stirred for 24 hours. The solids were recovered by filtration and washed with distilled water and dried. The ion exchange, filter, recover and wash sequence was repeated two additional times for each of the samples. The recovered NH 4 + exchanged material was analyzed for N, Na, Y, and Si, and is represented by the following formula on an anhydrous, oxide basis: 2.0(NH.sub.4).sub.2 O:0.7Na.sub.2 O:Y.sub.2 O.sub.3 :14.8SiO.sub.2 The recovered K+ exchanged material was analyzed for K, Na, Y, and Si, and is represented by the following formula on an anyhdrous, oxide basis: 1.2K.sub.2 O:1.5Na.sub.2 O:Y.sub.2 O.sub.3 :14.8SiO.sub.2 The recovered Ca 2+ exchanged material was analyzed for Ca, Na, Y, and Si, and is represented by the following formula on an anhydrous basis: 2.6CaO:0.1Na.sub.2 O:Y.sub.2 O.sub.3 :14.8SiO.sub.2 EXAMPLE 7 One gram of the product of Example 1 was placed in 25 ml of a 0.1M CaCl 2 solution and stirred for 24 hours. The solid was recovered by filtration, washed thoroughly with distilled water and dried. The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.12 vs9.41 m6.17 w5.43 m4.79 w3.67 w3.48 m3.08 s3.04 s2.97 s2.76 m2.40 w2.22 m2.09 w1.99 w______________________________________ EXAMPLE 8 One gram of the product of Example 3 was placed in 25 ml of a 0.1M CaCl 2 solution and stirred for 24 hours. The solid was recovered by filtration, washed thoroughly with distilled water and dried. The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.18 s7.03 vs6.55 s5.98 w5.76 w4.78 m4.44 m3.72 w3.50 m3.39 m3.09 s2.99 s2.96 s2.89 m2.74 m2.63 w2.54 w2.15 w______________________________________ EXAMPLE 9 One gram of the product of Example 4 was placed in 25 ml of a 0.1M CaCl 2 solution and stirred for 24 hours. The solid was recovered by filtration, washed thoroughly with distilled water and dried. The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.46 s6.20 m5.48 m3.87 w3.66 w3.48 w3.09 s3.06 s2.99 s2.80 m2.74 m2.51 w2.41 w2.29 w2.14 w2.10 w2.00 w______________________________________ EXAMPLE 10 0.100 gram of the solid prepared in Example 1 was placed in the quartz pan of McBain-Bakr balance. The system was evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample. Adsorption studies with both oxygen and n-hexane to determine adsorption properties of the molecular sieve were conducted. Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C. Adsorbed______________________________________Oxygen 19.7 3.46 -196 0.5Oxygen 96.6 3.46 -196 1.4n-hexane 46 4.3 23 1.2______________________________________ EXAMPLE 11 0.100 gram of the solid prepared in Example 7 was placed in the quartz pan of a McBain-Bakr balance. The system was then evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample. Adsorption studies with both oxygen and n-hexane to determine adsorption properties of the molecular sieve were conducted. Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C. Adsorbed______________________________________Oxygen 13 3.46 -196 0.87Oxygen 97 3.46 -196 1.37n-hexane 50.6 4.3 23 0.2______________________________________ EXAMPLE 12 0.100 gram of the solid prepared in Example 7 was placed in the quartz pan of a McBain-Bakr balance. The system was then evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample. Adsorption studies with both oxygen and n-hexane to determine adsorption properties of the molecular sieve were conducted. Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C. Adsorbed______________________________________Oxygen 19.7 3.46 -196 1.17Oxygen 96.6 3.46 -196 2.6n-hexane 46 4.3 24 1.86______________________________________ EXAMPLE 13 0.100 gram of the solid prepared in Example 9 was placed in the quartz pan of a McBain-Bakr balance. The system was then evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample. Adsorption studies with both oxygen and n-hexane to determine adsorption properties of the molecular sieve were conducted. Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C. Adsorbed______________________________________Oxygen 13 3.46 -196 3.65Oxygen 97 3.46 -196 7.0n-hexane 28.3 4.3 24 2.6n-hexane 50.6 4.3 24 4.0______________________________________ EXAMPLE 14 0.100 gram of the solid prepared in Example 8 was placed in the quartz pan of a McBain-Bakr balance. The system was then evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample. Adsorption studies with both oxygen and the n-hexane to determine adsorption properties of the molecular sieve were conducted. Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C. Adsorbed______________________________________Oxygen 13 3.46 -196 0.87Oxygen 97 3.46 -196 1.37n-hexane 50.6 4.3 23 0.2______________________________________ EXAMPLE 15 0.5 gram of the product prepared in Example 8 was placed in a porcelain crucible and heated to 400° C. in air and maintained at that temperature for four hours to provide a calcined product. The crucible was cooled and the product recovered. The x-ray diffraction pattern of this calcined product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.10 s7.02 s6.56 s6.01 m5.79 m4.78 w4.45 m3.72 w3.49 m3.38 m3.16 w3.09 m2.99 s2.88 m2.74 m2.63 w2.54 w2.15 w______________________________________ EXAMPLE 16 0.5 gram of the product prepared in Example 2 was placed in a porcelain crucible and heated to 400° C. in air and maintained at that temperature for four hours to provide a calcined product. The crucible was cooled and the product recovered. The x-ray diffraction pattern of this calcined product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.21 s9.35 w6.19 m5.59 w3.56 m3.08 s3.06 s2.99 s2.86 m2.81 m2.74 w2.69 w2.40 w2.27 w2.22 w2.16 w2.08 w2.01 w______________________________________ EXAMPLE 17 0.5 gram of the product prepared in Example 3 was placed in a porcelain crucible and heated to 400° C. in air and maintained at that temperature for four hours to provide a calcined product. The crucible was cooled and the product recovered. The x-ray diffraction pattern of this calcined product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.03 m6.98 s6.53 s6.01 w5.79 m4.77 w4.46 m3.70 m3.48 m3.38 m3.16 w3.09 m2.98 s2.89 m2.84 w2.73 m2.63 w2.56 w2.16 w______________________________________ While the invention has been explained in relation to its preferred embodiments, it is to be understood that various modifications thereof will become apparent to those skilled in the art upon reading the specification. Therefore, it is to be understood that the invention disclosed herein is intended to cover such modifications as fall within the scope of the appended claims.
A yttrium-silicate molecular sieve is disclosed which comprises a complex represented in terms of mole ratios of oxides as follows: aA.sub.2 O:Y.sub.2 O.sub.3 :bSiO.sub.2 :cH.sub.2 O wherein A is an alkali metal; a is a number ranging from about 0.5 to about 20; b is a number ranging from about 2 to about 400; and c is a number ranging from about 1 to about 500.
Briefly summarize the invention's components and working principles as described in the document.
[ "TECHNICAL FIELD This invention relates to molecular sieves and, more particularly, to yttrium silicate molecular sieves.", "BACKGROUND OF THE INVENTION The term "molecular sieve"", "refers to a wide variety of positive ion containing crystalline materials of both natural and synthetic varieties which exhibit the property of acting as sieves on a molecular scale.", "A major class of molecular sieves are crystalline aluminosilicates, although other crystalline materials are included in the broad definition.", "Examples of such other crystalline materials include coal, special active carbons, porous glass, microporous beryllium oxide powders, and layer silicates modified by exchange with organic cations.", "See, D. W. Breck, "Zeolite Molecular Sieves: Structure, Chemistry, and Use", John Wiley &", "Sons, 1974.", "Zeolites are crystalline, hydrated, framework aluminosilicates which are based on a three-dimensional network of AlO 4 and SiO 4 tetrahedra linked to each other by sharing all of the oxygens.", "Zeolites may be represented by the empirical formula M.sub[.", "].2/n O.Al.", "sub[.", "].2 O.sub[.", "].3.", "xSiO.", "sub[.", "].2.", "yH.", "sub[.", "].2 O wherein, x is generally equal to or greater than 2 since AlO 4 tetrahedra are joined only to SiO 4 tetrahedra, and n is the cation valence.", "The framework contains channels and interconnected voids which are occupied by the cation, M, and water molecules.", "The cations may be mobile and exchangeable to varying degrees by other cations.", "Intracrystalline zeolitic water in many zeolites is removed continuously and reversibly.", "In many other zeolites, mineral and synthetic, cation exchange or dehydration may produce structural changes in the framework.", "Ammonium and alkylammonium cations may be incorporated in synthetic zeolites, e.g., NH 4 , CH 3 NH 3 , (CH 3 ) 2 NH 2 , (CH 3 ) 3 NH, and (CH 3 ) 4 N. In some synthetic zeolites, aluminum cations may be substituted by gallium ions and silicon ions by germanium or phosphorus ions.", "The latter necessitates a modification of the structural formula.", "The structural formula of a zeolite is best expressed for the crystallographic unit cell as: M x/n [(AlO 2 ) x (SiO 2 ) y ].", "wH 2 O where M is the cation of valence n, w is the number of water molecules and the ratio y/x usually has values of 1-100 depending upon the structure.", "The sum (x+y) is the total number of tetrahedra in the unit cell.", "The complex within the [] represents the framework composition.", "The zeolites described in the patent literature and published journals are designated by letters or other convenient symbols.", "Exemplary of these materials are Zeolite A (U.S. Pat. No. 2,882,243), Zeolite X (U.S. Pat. No. 2,882,244), Zeolite Y (U.S. Pat. No. 3,130,007), Zeolite ZSM-5 (U.S. Pat. No. 3,702,886), Zeolite ZSM-11 (U.S. Pat. No. 3,708,979), and Zeolite ZSM-12 (U.S. Pat. No. 3,832,449).", "Although there are 34 species of zeolite minerals and about 100 types of synthetic zeolites, only a few have been found to have practical significance.", "Many of the zeolites, after dehydration, ae permeated by very small channel systems which are not interpenetrating and which may contain serious diffusion blocks.", "In other cases dehydration irreversibly disturbs the framework structure and the positions of metal cations, so that the structure partially collapses and dehydration is not completely reversible.", "To be efficiently used as a molecular sieve, the structure of the zeolite after complete dehydration must remain intact.", "There has been considerable interest in developing metallosilicates other than aluminosilicates which exhibit molecular sieve characteristics.", "For example, U.S. Pat. Nos. 3,329,480 and 3,329,481 disclose crystalline zircano-silicates and titano-silicates, respectively.", "U.S. Pat. No. 3,329,384 discloses Group IV-B metallosilicates.", "U.S. Pat. Nos. 4,208,305, 4,238,315 and 4,337,176 disclose iron silicates.", "U.S. Pat. No. 4,329,328 discloses zinco-, stanno-, and titano-silicates.", "European patent application Nos. 0 038 682 and 0 044 740 disclose cobalt silicates.", "European Patent Application No. 0 050 525 discloses nickel silicate.", "U.K. Patent Application No. GB 2,024,790 A discloses a silica-based material which has been modified with one or more elements which have entered the crystalline lattice of the silica in place of silicon atoms of the silica or in the form of salts of bisilicic or polysilicic acids.", "The elements identified as being suitable for making such silica-based materials are chromium, beryllium, titanium, vanadium, manganese, iron, cobalt, zinc, zirconium, rhodium, silver, tin, antimony and boron.", "U.S. Pat. No. 4,299,808 discloses chromosilicates formed by reacting an aqueous mixture of an oxide of silicon, a compound of chromium, a hydroxide of an alkali or an alkaline earth metal, and an alkylammonium cation or a precursor of an alkylammonium cation.", "U.S. Pat. Nos. 4,192,778 and 4,339,354 relate to a rare earth metal containing silicates.", "The former patent discloses rare earth exchanged zeolites of the faujasite type in which the equivalent of Na is less than 0.1 and the rare earth is at least 0.9 equivalents per gram atom of aluminum.", "The latter patent discloses a catalyst comprising a crystalline aluminosilicate such as zeolite Y, an inorganic matrix, and discrete particles of alumina, the catalyst having specified alkali metal and rare earth metal contents.", "U.S. Pat. No. 3,769,386 discloses zeolitic alumino-metallosilicates crystallized from an aqueous reaction mixture containing Na 2 O, SiO 2 , Al 2 O 3 and R 2/n wherein R is Mg, Ca, Y, Fe, Co, Ni or a rare earth metal and n is the valence of R. There remains a need for suitable metallosilicates that exhibit molecular sieve character, are stable at temperatures in excess of about 400° C., have relatively uniform pore sizes and are capable of desorbing an adsorbed phase without significant change in crystal structure.", "There is also a need for a relatively simplified method for making such metallosilicates.", "SUMMARY OF THE INVENTION The present invention relates to yttrium silicates which exhibit molecular sieve character, are stable at temperatures in excess of about 400° C., have relatively uniform pore sizes, and are capable of desorbing an adsorbed phase without significant change in crystal structure.", "The invention also relates to a relatively simplified method for making such yttrium silicates.", "Broadly stated, the present invention contemplates the provision of a molecular sieve comprising a complex represented in terms of mole ratios of oxides as follows: aA.", "sub[.", "].2 O:Y.", "sub[.", "].2 O.sub[.", "].3 :bSiO.", "sub[.", "].2 :cH.", "sub[.", "].2 O wherein A is an alkali metal;", "a is a number ranging from about 0.5 to about 20;", "b is a number ranging from about 2 to about 400;", "and c is a number ranging from about 1 to about 500.", "The invention further provides for a method for preparing a molecular sieving yttrium silicate comprising maintaining a mixture of a source of silicon, a source of yttrium, a source of alkali metal and water at a temperature in the range of about 50° C. to about 350° C. for an effective period of time to provide said yttrium silicate.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The molecular sieving yttrium silicates provided in accordance with the invention are complexes represented in terms of mole ratios of oxides by the formula aA.", "sub[.", "].2 O:Y.", "sub[.", "].2 O.sub[.", "].3 :bSiO.", "sub[.", "].2 :cH.", "sub[.", "].2 O wherein A is an alkali metal, preferably sodium, a is a number ranging from about 0.5 to about 20, preferably from about 0.8 to about 10;", "b is a number ranging from about 2 to about 400, preferably from about 3 to about 200;", "and c is a number ranging from about 1 to about 500, preferably from about 1 to about 200.", "These yttrium silicates exhibit two different general structures.", "One of the structures exhibits the following significant distinguishing lines among the reflections in the x-ray diffraction pattern, and is a preferred material formed when the Si/Y ratio is less than about six in the recovered solid.", "TABLE I______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.30 ± 0.40 s6.22 ± 0.15 s5.54 ± 0.15 w-m3.55 ± 0.08 w3.09 ± 0.06 s2.99 ± 0.05 s2.83 ± 0.04 w2.76 ± 0.03 w-m2.41 ± 0.03 w2.22 ± 0.03 w2.17 ± 0.02 w2.01 ± 0.02 w______________________________________ The other structure generally forms when the Si/Y ratio in the recovered solid is greater than about six.", "This material exhibits at least the following distinguishing lines among the reflections in its x-ray diffraction pattern: TABLE II______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.30 ± 0.50 m7.06 ± 0.15 vs6.57 ± 0.15 m6.08 ± 0.15 w5.83 ± 0.10 w4.80 ± 0.10 m4.48 ± 0.08 m3.74 ± 0.08 w3.48 ± 0.06 w3.09 ± 0.05 m2.99 ± 0.05 m-s2.90 ± 0.04 w-m2.73 ± 0.04 m2.16 ± 0.03 w______________________________________ These general patterns of significant x-ray reflections can also be attributed to the calcined and ion exchange forms of the yttrium silicates, although minor line shifts usually occur in the materials when these processes are performed.", "The values were determined by standard techniques.", "The relative intensities are given in terms of symbols: vs=very strong;", "s=strong;", "m=medium;", "w=weak;", "and vw=very weak.", "All x-ray patterns are obtained using standard x-ray powder diffraction techniques.", "The radiation source is a standard intensity, copper target, x-ray tube operated at 40 Kv and 20 ma.", "The diffraction pattern from the K alpha radiation is suitably recorded by an x-ray spectrometer scintillation counter, plus height analyzer and strip chart recorder.", "Flat compressed powder samples are scanned at 1° per minute, using a two second time constant.", "Interplanar spacings (d) are obtained from the position if the diffraction peaks expressed as 2θ where θ is the Bragg angle as observed on the strip chart.", "Intensities are determined from the heights of diffraction peaks after subtracting background.", "As will be understood by those skilled in the art, the determination of the parameter 2θ, irrespective of the technique employed, is subject to both human and mechanical error, which in combination, can improve an uncertainty of about 0.4° on each reported value of 2θ.", "This uncertainty is, of course, also manifested in the reported values of the d-spacings, which are calculated from the 2θ values.", "This impression is general throughout the art and is not sufficient to preclude the differentiation of the present crystalline materials from each other and from the compositions of the prior art.", "In a preferred embodiment of the invention, the mixture provided for in the process of the invention for making the yttrium silicates is preferably prepared in three steps.", "First, the silicon source is mixed in water to provide a first mixture.", "This first mixture is preferably in the form of a colloidal dispersion.", "Second, the yttrium source is mixed with water to provide a second mixture.", "This second mixture is usually in the form of a dispersion or solution.", "Third, these first and second mixtures are mixed together to form a gel.", "The source of alkali metal is added to the gel with stirring.", "The Si to yttrium mole ratio is preferably in the range of about 1 to about 200, more preferably about 2 to about 30.", "The OH-- to Y mole ratio is preferably in the range of about 1 to about 25.", "The H 2 O to Y mole ratio is preferably in the range of about 50 to about 2500.", "The alkali metal to Y mole ratio is preferably in the range of about 1 to about 25, more preferably about 3 to about 20.", "The silicon source can be any source that provides silicon oxide, hydroxide or alkoxide.", "Such sources include silica gel, silicic acid, silica sol and the silicates.", "Included within the silicates are the alkali and alkaline earth metal silicates with sodium silicate and potassium silicate being preferred.", "The alkoxides include those alkoxides of up to about 10, preferably up to about 6 carbon atoms.", "The silica sols are aqueous colloidal dispersions containing colloidal silica particles.", "The solids content of these colloidal dispersions generally ranges up to about 70% by weight, and is preferably in the range of about 5% to about 50%.", "These dispersions usually include an effective amount of an anionic (e.g., acetate, halogen, etc.) or cationic (e.g., alkali metal, ammonium, etc.) stabilizing agent to stabilize the dispersion.", "Generally the level of addition of such stabilizing agents is up to about 10% by weight of the solids in the dispersion.", "A commercially available silica sol that is particularly useful is Ludox AS-30 which is a product of DuPont identified as an ammonium stabilized silica sol containing 30% by weight silica.", "The yttrium source can be any compound that provides trivalent yttrium.", "These compounds include oxides, hydroxides, inorganic salts (e.g., nitrates, sulfates, halides, carbonates, silicates, and the like) as well as the organic salts, (e.g., acetates, formates, butyrates, propionates, benzylates and the like).", "Yttrium chloride, yttrium chloride hydrate, and yttrium oxide are preferred.", "The alkali metal source can be any metal compound that provides the desired alkali metal cation.", "These compounds include the oxides, hydroxides, inorganic salts (e.g., nitrates, halides, sulfates, carbonates, silicates, and the like) as well as the organic salts, (e.g., acetates, formates, butyrates, propionates, benzylates and the like).", "Sodium hydroxide is preferred.", "In the method of the present invention for making the yttrium silicates, the mixture containing water, the source of silicon, the yttrium source, and the alkali metal source is preferably thoroughly mixed and then placed in a reactor.", "The reactor is preferably an enclosed reactor (e.g., a static bomb style reactor).", "The contents are heated to a temperature in the range of preferably about 50° C. to about 350° C., more preferably about 100° C. to about 200° C., under autogeneous pressure for an effective period of time to provide the desired molecular sieving yttrium silicate, preferably for about one hour to about 30 days, more preferably about 6 hours to about 14 days.", "The contents of the reactor are then allowed to cool to room temperature.", "The crystalline solids are separated from the mother liquor and washed thoroughly with water.", "Separation can be effected by conventional filtration techniques.", "The crystalline solids are then allowed to dry in air, such solids being the desired molecular sieving yttrium silicates of the invention.", "The yttrium silicates of the invention can be ion exchanged with an ammonium salt or a salt of a catalytically active metal.", "The salt of the catalytically active metal is preferably the salt of a Group VIII, IB or IIB metal, with zinc, copper, nickel, cobalt and iron being preferred.", "The anionic portions of these salts include the nitrates, phosphates, sulfates, acetates and halides.", "The cation exchange procedure employed herein is entirely conventional.", "Briefly, the yttrium silicate and the ammonium salt or salt of catalytically active metal are dispersed in water for an effective period of time and at a sufficient temperature to provide the desired ion-exchanged yttrium silicate.", "Preferably the yttrium silicate and the salt are so dispersed for a few minutes to several hours, preferably about one to about ten hours, and maintained at about room temperature to about the boiling point of the water.", "The ion-exchanged yttrium silicate is then filtered and washed.", "Optionally, the ion-exchanged yttrium silicates can be heat treated in an inert, oxidizing or reducing atmosphere using the following heat treating procedures to convert the ion-exchanged species to a more active form.", "The heat treating procedure is conducted at a temperature of about 200° C. to about 900° C., preferably about 300° C. to about 600° C. The time period for this heat treating step is dependent upon the mass of material being treated.", "Preferably the heat treating step is conducted for at least about 30 minutes, but this time period can be more or less than 30 minutes depending upon the mass of material being treated.", "The inert atmosphere is preferably nitrogen, argon, helium or neon.", "The reducing atmosphere is hydrogen or a mixture of hydrogen and one of the above-indicated insert gases.", "The reducing atmosphere can contain from about 1% to about 100% hydrogen, preferably about 1% to about 20% hydrogen, with the remainder being inert gas.", "The oxidizing atmosphere can be oxygen or a mixture of oxygen and one of the above-indicated inert gases.", "The oxidizing atmosphere can contain from about 1% to about 100% oxygen, preferably from about 1% to about 20% oxygen with the remainder being inert as.", "A preferred oxidizing atmosphere is air.", "In order to further illustrate the present invention, the following examples are provided.", "Unless otherwise indicated, in the following examples as well as throughout the specification and in the claims, all parts and percentages are by weight, and all temperatures are in degrees centrigrade.", "EXAMPLE 1 0.985 grams of yttrium chloride hydrate were dissolved in 2 grams of water.", "This solution was mixed with 1.3 grams of Ludox AS-30 and stirred.", "1.5 grams of a 50% sodium hydroxide solution diluted in 2 grams of water were added to the mixture.", "The mixture was stirred until a uniform gel was formed.", "The Si/Y mole ratio was about 2.", "The Na/Y mole ratio was about 5.9.", "The H 2 O/Y mole ratio was about 70.", "The mixture was charged to a Teflon lined static bomb reactor.", "The reactor was placed in an oven at 170° C. for 12 days.", "The reactor was removed from the oven and cooled.", "The product was removed from the reactor, filtered, washed with distilled water and dried.", "Elemental analysis and the determination of the loss on ignition (LOI) to 1000° C. for the recovered solid resulted in the following formulation on an oxide basis: 0.9Na.", "sub[.", "].2 O:Y.", "sub[.", "].2 O.sub[.", "].3 :3.1SiO.", "sub[.", "].2 :2.6H.", "sub[.", "].2 O The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.42 s9.56 w6.22 m5.82 w5.64 w4.79 w3.76 w3.55 w3.09 s3.08 s2.99 s2.88 w2.82 m2.76 w2.69 w2.41 w2.26 w2.22 w2.06 w2.01 w______________________________________ EXAMPLE 2 0.492 grams of yttrium chloride hydrate were dissolved in 2 grams of water.", "This solution was mixed with 1.3 grams of Ludox AS-30 and stirred.", "1.5 grams of a 50% sodium hydroxide solution diluted in 2 grams of water were added to the mixture.", "The mixture was stirred until a uniform gel was formed.", "The Si/Y mole ratio was about 4.", "The Na/Y mole ratio was about 11.6.", "The H 2 O/Y mole ratio was about 132.", "The mixture was charged to a Teflon lined static bomb reactor.", "The reactor was placed in an oven at 170° C. for 12 days.", "The reactor was removed from the oven and cooled.", "The product was removed from the reactor, filtered, washed with distilled water and dried.", "Elemental analysis and the determination of the LOI to 1000° C. for the recovered solid resulted in the following formulation on an oxide basis: 1.4Na.", "sub[.", "].2 O:Y.", "sub[.", "].2 O.sub[.", "].3 :4.7SiO.", "sub[.", "].2 :3.6H.", "sub[.", "].2 O The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.34 vs6.20 s5.54 w4.80 w3.52 w3.09 s2.99 s2.84 m2.76 m2.41 w2.23 w2.16 w2.06 w2.01 w______________________________________ EXAMPLE 3 9.75 grams of yttrium chloride hydrate were dissolved in 450 grams of water to provide a first mixture.", "97.5 grams of Ludox AS-30 were diluted with 525 grams of water to provide a second mixture.", "The first and second mixtures were mixed together and stirred.", "45 grams of a 50% sodium hydroxide solution diluted in 225 grams of water were added to the mixture.", "The mixture was stirred until a uniform gel was formed.", "The Si/Y mole ratio was about 15.2.", "The Na/Y mole ratio was about 17.5.", "The H 2 O/Y mole ratio was about 2050.", "The mixture was charged to a Teflon lined static bomb reactor.", "The reactor was placed in an oven at 170° C. for 4 days.", "The reactor was removed from the oven and cooled.", "The product was removed from the reactor, filtered, washed with distilled water and dried.", "Elemental analysis and the determination of the LOI to 1000° C. for the recovered solid resulted in the following formulation on an oxide basis: 2.7Na.", "sub[.", "].2 O:Y.", "sub[.", "].2 O.sub[.", "].3 :14.8SiO.", "sub[.", "].2 :10.1H.", "sub[.", "].2 O The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.38 m7.07 vs6.60 m6.08 w5.83 w4.80 m4.48 m3.74 w3.50 w3.40 m3.10 m3.00 m2.90 w2.74 m2.64 w2.56 w2.34 w2.15 w______________________________________ EXAMPLE 4 0.492 grams of yttrium chloride hydrate were dissolved in one gram of water.", "This solution was mixed with 1.3 grams of Ludox AS-30 and stirred.", "One gram of a 50% sodium hydroxide solution diluted in one gram of water was added to the mixture.", "The mixture was stirred until a uniform gel was formed.", "The Si/Y mole ratio was about 4.", "The Na/Y mole ratio was about 7.7.", "The H 2 O/Y mole ratio was about 65.", "The mixture was charged to a Teflon lined static bomb reactor.", "The reactor was placed in an oven at 170° C. for 4 days.", "The reactor was removed from the oven and cooled.", "The product was removed from the reactor, filtered, washed with distilled water and dried.", "The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation ) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.40 s9.64 w6.19 m5.63 w3.58 m3.09 s3.08 s2.98 s2.88 s2.83 m2.75 m2.68 w2.41 w2.27 w2.22 w2.18 w2.10 w2.02 w______________________________________ EXAMPLE 5 0.06 grams of yttrium chloride hydrate were dissolved in 3.75 grams of water.", "This solution was mixted with 3.9 grams of Ludox AS-30 and stirred.", "1.5 grams of a 50% sodium hydroxide solution diluted in 3.75 grams of water were added to the mixture.", "The mixture was stirred until a uniform gel was formed.", "The Si/Y mole ratio was about 98.", "The Na/Y mole ratio was about 95.", "The H 2 O/Y mole ratio was about 2100.", "The mixture was charged to a Teflon lined static bomb reactor.", "The reactor was placed in an oven at 170° C. for 5 days.", "The reactor was removed from the oven and cooled.", "The product was removed from the reactor, filtered, washed with distilled water and dried.", "The x-ray diffraction pattern of this dired product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.60 m7.01 s6.57 m5.85 w5.63 w4.77 w4.48 w3.69 w3.46 w3.09 w2.98 s2.73 w2.15 w______________________________________ EXAMPLE 6 Ion-exchanged yttrium silicates were prepared by placing 0.5 gram of the product of Example 3 in each of three flasks containing 20 ml of 0.1M solutions of NH 4 Cl, KCl, and CaCl 2 , respectively.", "The mixtures were stirred for 24 hours.", "The solids were recovered by filtration and washed with distilled water and dried.", "The ion exchange, filter, recover and wash sequence was repeated two additional times for each of the samples.", "The recovered NH 4 + exchanged material was analyzed for N, Na, Y, and Si, and is represented by the following formula on an anhydrous, oxide basis: 2.0(NH.", "sub[.", "].4).", "sub[.", "].2 O:0.7Na.", "sub[.", "].2 O:Y.", "sub[.", "].2 O.sub[.", "].3 :14.8SiO.", "sub[.", "].2 The recovered K+ exchanged material was analyzed for K, Na, Y, and Si, and is represented by the following formula on an anyhdrous, oxide basis: 1.2K.", "sub[.", "].2 O:1.5Na.", "sub[.", "].2 O:Y.", "sub[.", "].2 O.sub[.", "].3 :14.8SiO.", "sub[.", "].2 The recovered Ca 2+ exchanged material was analyzed for Ca, Na, Y, and Si, and is represented by the following formula on an anhydrous basis: 2.6CaO:0.1Na.", "sub[.", "].2 O:Y.", "sub[.", "].2 O.sub[.", "].3 :14.8SiO.", "sub[.", "].2 EXAMPLE 7 One gram of the product of Example 1 was placed in 25 ml of a 0.1M CaCl 2 solution and stirred for 24 hours.", "The solid was recovered by filtration, washed thoroughly with distilled water and dried.", "The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.12 vs9.41 m6.17 w5.43 m4.79 w3.67 w3.48 m3.08 s3.04 s2.97 s2.76 m2.40 w2.22 m2.09 w1.99 w______________________________________ EXAMPLE 8 One gram of the product of Example 3 was placed in 25 ml of a 0.1M CaCl 2 solution and stirred for 24 hours.", "The solid was recovered by filtration, washed thoroughly with distilled water and dried.", "The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.18 s7.03 vs6.55 s5.98 w5.76 w4.78 m4.44 m3.72 w3.50 m3.39 m3.09 s2.99 s2.96 s2.89 m2.74 m2.63 w2.54 w2.15 w______________________________________ EXAMPLE 9 One gram of the product of Example 4 was placed in 25 ml of a 0.1M CaCl 2 solution and stirred for 24 hours.", "The solid was recovered by filtration, washed thoroughly with distilled water and dried.", "The x-ray diffraction pattern of this dried product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.46 s6.20 m5.48 m3.87 w3.66 w3.48 w3.09 s3.06 s2.99 s2.80 m2.74 m2.51 w2.41 w2.29 w2.14 w2.10 w2.00 w______________________________________ EXAMPLE 10 0.100 gram of the solid prepared in Example 1 was placed in the quartz pan of McBain-Bakr balance.", "The system was evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample.", "Adsorption studies with both oxygen and n-hexane to determine adsorption properties of the molecular sieve were conducted.", "Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C.", "Adsorbed______________________________________Oxygen 19.7 3.46 -196 0.5Oxygen 96.6 3.46 -196 1.4n-hexane 46 4.3 23 1.2______________________________________ EXAMPLE 11 0.100 gram of the solid prepared in Example 7 was placed in the quartz pan of a McBain-Bakr balance.", "The system was then evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample.", "Adsorption studies with both oxygen and n-hexane to determine adsorption properties of the molecular sieve were conducted.", "Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C.", "Adsorbed______________________________________Oxygen 13 3.46 -196 0.87Oxygen 97 3.46 -196 1.37n-hexane 50.6 4.3 23 0.2______________________________________ EXAMPLE 12 0.100 gram of the solid prepared in Example 7 was placed in the quartz pan of a McBain-Bakr balance.", "The system was then evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample.", "Adsorption studies with both oxygen and n-hexane to determine adsorption properties of the molecular sieve were conducted.", "Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C.", "Adsorbed______________________________________Oxygen 19.7 3.46 -196 1.17Oxygen 96.6 3.46 -196 2.6n-hexane 46 4.3 24 1.86______________________________________ EXAMPLE 13 0.100 gram of the solid prepared in Example 9 was placed in the quartz pan of a McBain-Bakr balance.", "The system was then evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample.", "Adsorption studies with both oxygen and n-hexane to determine adsorption properties of the molecular sieve were conducted.", "Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C.", "Adsorbed______________________________________Oxygen 13 3.46 -196 3.65Oxygen 97 3.46 -196 7.0n-hexane 28.3 4.3 24 2.6n-hexane 50.6 4.3 24 4.0______________________________________ EXAMPLE 14 0.100 gram of the solid prepared in Example 8 was placed in the quartz pan of a McBain-Bakr balance.", "The system was then evacuated (10 -5 torr) and the sample chamber was heated for 18 hours at 200° C. to remove adsorbed species from the sample.", "Adsorption studies with both oxygen and the n-hexane to determine adsorption properties of the molecular sieve were conducted.", "Representative data from these experiments appears in the following table: ______________________________________Pressure Kinetic Temperature Weight %(torr) Diameters (A) °C.", "Adsorbed______________________________________Oxygen 13 3.46 -196 0.87Oxygen 97 3.46 -196 1.37n-hexane 50.6 4.3 23 0.2______________________________________ EXAMPLE 15 0.5 gram of the product prepared in Example 8 was placed in a porcelain crucible and heated to 400° C. in air and maintained at that temperature for four hours to provide a calcined product.", "The crucible was cooled and the product recovered.", "The x-ray diffraction pattern of this calcined product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.10 s7.02 s6.56 s6.01 m5.79 m4.78 w4.45 m3.72 w3.49 m3.38 m3.16 w3.09 m2.99 s2.88 m2.74 m2.63 w2.54 w2.15 w______________________________________ EXAMPLE 16 0.5 gram of the product prepared in Example 2 was placed in a porcelain crucible and heated to 400° C. in air and maintained at that temperature for four hours to provide a calcined product.", "The crucible was cooled and the product recovered.", "The x-ray diffraction pattern of this calcined product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________11.21 s9.35 w6.19 m5.59 w3.56 m3.08 s3.06 s2.99 s2.86 m2.81 m2.74 w2.69 w2.40 w2.27 w2.22 w2.16 w2.08 w2.01 w______________________________________ EXAMPLE 17 0.5 gram of the product prepared in Example 3 was placed in a porcelain crucible and heated to 400° C. in air and maintained at that temperature for four hours to provide a calcined product.", "The crucible was cooled and the product recovered.", "The x-ray diffraction pattern of this calcined product exhibited the following significant lines (Cu K alpha radiation) (w=weak, m=medium, s=strong, vs=very strong): ______________________________________Interplanar RelativeSpacing d(A) Intensity______________________________________12.03 m6.98 s6.53 s6.01 w5.79 m4.77 w4.46 m3.70 m3.48 m3.38 m3.16 w3.09 m2.98 s2.89 m2.84 w2.73 m2.63 w2.56 w2.16 w______________________________________ While the invention has been explained in relation to its preferred embodiments, it is to be understood that various modifications thereof will become apparent to those skilled in the art upon reading the specification.", "Therefore, it is to be understood that the invention disclosed herein is intended to cover such modifications as fall within the scope of the appended claims." ]
The present invention relates to the control and safety devices of a domestic pressure cooker. BACKGROUND OF THE INVENTION ES-2053186 (EP-0489012) discloses a pressure cooker of the type with two superimposed handles, the lid one and the pan one, which has a safety device actuated by means of an operating button that slides towards a locking member provided with a pin which engages in an outward bent rim of the pan. The locking pin is held engaged by means of the force of a coaxial spring. A valve stem lifted by the pressure in the pan stops the locking member from being retracted, so the lid cannot be turned as long as there is any residual pressure in the pan. The locking device also prevents the pressurizing of the cooker in the event of the two handles not being aligned properly because in that case the locking member cannot be moved forwards to engage with the pan. To open the cooker after cooking, the valve stem drops under its own weight from its lock position and the operating button can then be retracted, the lid handle disengages from the pan and the lid can be turned for opening. The locking member of the known device is housed inside the lid handle and it is L-shaped with the long arm arranged horizontally, which obstructs the valve stem in the "release", condition and prevents it from rising. DE-2705712 discloses a lid locking device on a pressure cooker comprising an actuating button and a mechanism for transmitting the movement to the locking member, which is pivoting. DE-3623546-A discloses a pressure cooker with a safety device housed in the handle, which has a vertical sliding pushbutton provided with a return spring and a mechanism for stopping the lid from turning through the assistance of a valve cone for pressurizing the cooker pan. The lock actuating member pivots under the pressure of the pushbutton, and it has two ends, one of which engages on the pan rim so that the lid is left free to turn, while the other end is connected directly to the valve cone, for raising it from its seat and the consequent depressurizing of the pan. SUMMARY OF THE INVENTION The object of the present invention is a domestic pressure cooker with a safety device to stop the lid from turning and prevent the opening of the cooker as long as residual pressure remains, as defined in the claims. The pressure cooker is the upper and lower superimposed radial handle type, which has an actuating button with vertical movement in the lid handle and a mechanism with a horizontally sliding locking member operated by the button, which, with the assistance of a valve body that rises, prevents the lid from turning as long as there is any residual pressure in the pan. The safety device prevents the pressurizing of the pan, until the two handles are perfectly aligned one above the other. The operation that is carried out by means of the button and the locking mechanism according to the invention, both for locking the lid to prevent it turning and for releasing it, is the same in both cases, since in either operation the button will push the locking member in the direction opposite to the direction it was moved in the previous operation. The button always remains up after performing a locking or releasing operation, and its vertical movement is achieved with a light pressure of the finger and it is converted afterwards into simple horizontal translational movement of the locking member by means of a pivoting transmission member linked to the button. The lid turn locked condition is identified by a visible rod, which is raised by the action of the locking member. The locking member also incorporates a vertical stop plate, to prevent releasing backward movement, with the assistance of the excess pressure safety valve body, utilizing the fact that this is raised above the lid of the cooker, while it also includes a retractable catch, which prevents the movement of the locking member for the pressurizing of the pan, until the two handles are fully superimposed. The configuration of the pushbutton, of the locking member and of the pivoting transmission member simplify the construction of the safety device, assembled in this way with three moulded plastic pieces and housed wholly in the lid handle, without any of them protruding. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial sectional view of the pressure cooker with a safety device to prevent the opening of the cooker, according to the invention. FIG. 2 is a sectional view of the safety device according to II--II of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION With reference to FIGS. 1 and 2, a preferred embodiment of the pressure cooker according to the invention comprises the cooking pan 2, the cooker lid 3, an upper lid handle 4 and a lower pan handle 5, and a safety device that locks the opening of the cooker, which comprises a built-in locking mechanism in the lid handle 4, a residual pressure valve 7, and a rod 8 indicating the locked condition of the cooker. The locking mechanism 6 comprises an operating pushbutton 9, a locking member 10, a rocker 17 for transmitting the movement of the button 9 to the locking member 10 and a catch 11, which assures that handles 4 and 5 are fully superimposed. The locking member 10 is housed in an internal cavity 4' in the upper handle 4, and it is shaped in the form of a double "L", with a vertical arm 10b and two horizontal arms 10a and 10c, front and rear respectively, extending radially from the vertical arm 10b each in the opposite direction to the other, and in addition it has a tab 10d issuing from the bottom of the vertical arm 10b in direction towards the pan. The catch 11 is retractable within a front projection 10f of the locking member, and it has an internal spring which keeps it jutting out, thereby preventing the locking member from being moved. Now the valve 7 cannot be lifted and the steam will escape via an outer discharge duct 16. The condition required to carry out the locking operation is that, after completing the lock turn of the lid 3 to start cooking, the handles 4 and 5 are aligned and catch 11, being pressed by a surface jutting out from the lower handle 5, is retracted, while in the meantime it can push the locking member 10 forward. The tab 10d will now move forward with the locking member 10, which is pushed by button 9 to interlock with the horizontal bent rim 2a of the pan and thereby assures the locking of the lid 3. The condition of the safety device shown in the figure is that of the cooker with the lid locked but still not pressurized, ready for the start of cooking. The raised stem 8 indicates the lock condition. The valve body 7, which passes through a hole in the lid 3, is still dropped, but it can now be raised according to arrow 15 by steam pressure and it will seal this lid hole in the steam discharge duct. When the valve body remains up 7, its end is housed in a recess 14 in the front arm 10a of the locking member, behind a vertical stop plate incorporated into the latter, which comes up against the raised valve body 7, thereby preventing the locking member 10 from being retracted for release. The stem 8, which emerges from the upper handle 4 to indicate the lock actuated condition, is supported on the sloping base of a surface cavity 10e in the front arm 10a. The condition required to execute the operation to release the lid 3 after cooking is that the valve 7 has dropped due to absence of pressure in the pan 2. The user presses the button 9 according to the arrow 12, and the locking member 10 is retracted to occupy a position 23, represented in FIG. 1 as a dotted line, disengaging the tab 10d, so that the lid handle 4 is thereby free to turn. The rocker 17 for transmitting the movement, as shown in FIG. 2, is housed in a cavity 9' in the button and converts the vertical movement 12 of the button 9 into horizontal travel of the locking member 10. The rocker 17 has an inverted U-shape and its vertical arms are kept outside the contour of the button 9 and they pivot around its horizontal spindle 18 supported in a guide in the button 9. These lateral arms of the rocker 17 terminate in two horizontal pads 19 projecting outwards. The rear arm 10c of the locking member has a surface in the form of a ramp 20 on which the two lateral pads 19 of the rocker make contact when the button 9 is pressed to lock the lid or to release it. The ramp 20 has a crest and an opposing sloping surface on either side, forming two end cavities 22 and 22' where the pads 19 rest and on which they exert pressure to move the locking member 10 in one direction or the other. After an operation is carried out, the button 9 is kept up away from the locking member, as shown in FIGS. 1 and 2, by the force of a vertical coil spring resting on the bottom 24 of the internal cavity 4' of the upper handle. The vertical downward movement according to arrow 12 of the button 9 brings about the contact of the rocker pads 19 with the ramp 20, with the result that they slip towards the surface 22' of the rear cavity of the ramp and they push the locking member 10 outwards to disengage tab 10d. When pressed down for the opposing operation, the button 9 forces the rocker 17 to pivot to the opposite side until the pads 19 occupy the front cavity 22 of the ramp, and they push the locking member 10 towards the pan to engage the tab 10d. The valve body 7 is dropped and the vertical partition 13 encounters no impediment to its forward movement towards the pan 2. The indicator rod 8 climbs the sloping surface 10e and becomes visible.
A pressure cooker with a safety device to prevent the lid from turning includes a lid handle and a cooking pan handle. The safety device is built-in to the lid handle, and includes a locking mechanism, a vertical sliding pushbutton that actuates a locking member, a residual pressure valve, and a cooker closed condition indicator rod. The pushbutton exerts pressure on a rocker, which moves the locking member horizontally over two opposing slope ramps in the surface of the locking member.
Identify and summarize the most critical features from the given passage.
[ "The present invention relates to the control and safety devices of a domestic pressure cooker.", "BACKGROUND OF THE INVENTION ES-2053186 (EP-0489012) discloses a pressure cooker of the type with two superimposed handles, the lid one and the pan one, which has a safety device actuated by means of an operating button that slides towards a locking member provided with a pin which engages in an outward bent rim of the pan.", "The locking pin is held engaged by means of the force of a coaxial spring.", "A valve stem lifted by the pressure in the pan stops the locking member from being retracted, so the lid cannot be turned as long as there is any residual pressure in the pan.", "The locking device also prevents the pressurizing of the cooker in the event of the two handles not being aligned properly because in that case the locking member cannot be moved forwards to engage with the pan.", "To open the cooker after cooking, the valve stem drops under its own weight from its lock position and the operating button can then be retracted, the lid handle disengages from the pan and the lid can be turned for opening.", "The locking member of the known device is housed inside the lid handle and it is L-shaped with the long arm arranged horizontally, which obstructs the valve stem in the "release", condition and prevents it from rising.", "DE-2705712 discloses a lid locking device on a pressure cooker comprising an actuating button and a mechanism for transmitting the movement to the locking member, which is pivoting.", "DE-3623546-A discloses a pressure cooker with a safety device housed in the handle, which has a vertical sliding pushbutton provided with a return spring and a mechanism for stopping the lid from turning through the assistance of a valve cone for pressurizing the cooker pan.", "The lock actuating member pivots under the pressure of the pushbutton, and it has two ends, one of which engages on the pan rim so that the lid is left free to turn, while the other end is connected directly to the valve cone, for raising it from its seat and the consequent depressurizing of the pan.", "SUMMARY OF THE INVENTION The object of the present invention is a domestic pressure cooker with a safety device to stop the lid from turning and prevent the opening of the cooker as long as residual pressure remains, as defined in the claims.", "The pressure cooker is the upper and lower superimposed radial handle type, which has an actuating button with vertical movement in the lid handle and a mechanism with a horizontally sliding locking member operated by the button, which, with the assistance of a valve body that rises, prevents the lid from turning as long as there is any residual pressure in the pan.", "The safety device prevents the pressurizing of the pan, until the two handles are perfectly aligned one above the other.", "The operation that is carried out by means of the button and the locking mechanism according to the invention, both for locking the lid to prevent it turning and for releasing it, is the same in both cases, since in either operation the button will push the locking member in the direction opposite to the direction it was moved in the previous operation.", "The button always remains up after performing a locking or releasing operation, and its vertical movement is achieved with a light pressure of the finger and it is converted afterwards into simple horizontal translational movement of the locking member by means of a pivoting transmission member linked to the button.", "The lid turn locked condition is identified by a visible rod, which is raised by the action of the locking member.", "The locking member also incorporates a vertical stop plate, to prevent releasing backward movement, with the assistance of the excess pressure safety valve body, utilizing the fact that this is raised above the lid of the cooker, while it also includes a retractable catch, which prevents the movement of the locking member for the pressurizing of the pan, until the two handles are fully superimposed.", "The configuration of the pushbutton, of the locking member and of the pivoting transmission member simplify the construction of the safety device, assembled in this way with three moulded plastic pieces and housed wholly in the lid handle, without any of them protruding.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial sectional view of the pressure cooker with a safety device to prevent the opening of the cooker, according to the invention.", "FIG. 2 is a sectional view of the safety device according to II--II of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION With reference to FIGS. 1 and 2, a preferred embodiment of the pressure cooker according to the invention comprises the cooking pan 2, the cooker lid 3, an upper lid handle 4 and a lower pan handle 5, and a safety device that locks the opening of the cooker, which comprises a built-in locking mechanism in the lid handle 4, a residual pressure valve 7, and a rod 8 indicating the locked condition of the cooker.", "The locking mechanism 6 comprises an operating pushbutton 9, a locking member 10, a rocker 17 for transmitting the movement of the button 9 to the locking member 10 and a catch 11, which assures that handles 4 and 5 are fully superimposed.", "The locking member 10 is housed in an internal cavity 4'", "in the upper handle 4, and it is shaped in the form of a double "L", with a vertical arm 10b and two horizontal arms 10a and 10c, front and rear respectively, extending radially from the vertical arm 10b each in the opposite direction to the other, and in addition it has a tab 10d issuing from the bottom of the vertical arm 10b in direction towards the pan.", "The catch 11 is retractable within a front projection 10f of the locking member, and it has an internal spring which keeps it jutting out, thereby preventing the locking member from being moved.", "Now the valve 7 cannot be lifted and the steam will escape via an outer discharge duct 16.", "The condition required to carry out the locking operation is that, after completing the lock turn of the lid 3 to start cooking, the handles 4 and 5 are aligned and catch 11, being pressed by a surface jutting out from the lower handle 5, is retracted, while in the meantime it can push the locking member 10 forward.", "The tab 10d will now move forward with the locking member 10, which is pushed by button 9 to interlock with the horizontal bent rim 2a of the pan and thereby assures the locking of the lid 3.", "The condition of the safety device shown in the figure is that of the cooker with the lid locked but still not pressurized, ready for the start of cooking.", "The raised stem 8 indicates the lock condition.", "The valve body 7, which passes through a hole in the lid 3, is still dropped, but it can now be raised according to arrow 15 by steam pressure and it will seal this lid hole in the steam discharge duct.", "When the valve body remains up 7, its end is housed in a recess 14 in the front arm 10a of the locking member, behind a vertical stop plate incorporated into the latter, which comes up against the raised valve body 7, thereby preventing the locking member 10 from being retracted for release.", "The stem 8, which emerges from the upper handle 4 to indicate the lock actuated condition, is supported on the sloping base of a surface cavity 10e in the front arm 10a.", "The condition required to execute the operation to release the lid 3 after cooking is that the valve 7 has dropped due to absence of pressure in the pan 2.", "The user presses the button 9 according to the arrow 12, and the locking member 10 is retracted to occupy a position 23, represented in FIG. 1 as a dotted line, disengaging the tab 10d, so that the lid handle 4 is thereby free to turn.", "The rocker 17 for transmitting the movement, as shown in FIG. 2, is housed in a cavity 9'", "in the button and converts the vertical movement 12 of the button 9 into horizontal travel of the locking member 10.", "The rocker 17 has an inverted U-shape and its vertical arms are kept outside the contour of the button 9 and they pivot around its horizontal spindle 18 supported in a guide in the button 9.", "These lateral arms of the rocker 17 terminate in two horizontal pads 19 projecting outwards.", "The rear arm 10c of the locking member has a surface in the form of a ramp 20 on which the two lateral pads 19 of the rocker make contact when the button 9 is pressed to lock the lid or to release it.", "The ramp 20 has a crest and an opposing sloping surface on either side, forming two end cavities 22 and 22'", "where the pads 19 rest and on which they exert pressure to move the locking member 10 in one direction or the other.", "After an operation is carried out, the button 9 is kept up away from the locking member, as shown in FIGS. 1 and 2, by the force of a vertical coil spring resting on the bottom 24 of the internal cavity 4'", "of the upper handle.", "The vertical downward movement according to arrow 12 of the button 9 brings about the contact of the rocker pads 19 with the ramp 20, with the result that they slip towards the surface 22'", "of the rear cavity of the ramp and they push the locking member 10 outwards to disengage tab 10d.", "When pressed down for the opposing operation, the button 9 forces the rocker 17 to pivot to the opposite side until the pads 19 occupy the front cavity 22 of the ramp, and they push the locking member 10 towards the pan to engage the tab 10d.", "The valve body 7 is dropped and the vertical partition 13 encounters no impediment to its forward movement towards the pan 2.", "The indicator rod 8 climbs the sloping surface 10e and becomes visible." ]
PRIORITY This application claims priority under 35 U.S.C. §119(a) to a Korean Patent Application filed in the Korean Intellectual Property Office on Dec. 28, 2006 and assigned Ser. No. 2006-137082, the disclosure of which is incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a method and apparatus for modulating symbols in a wireless communication system, and in particular, to a method and apparatus for efficiently modulating symbols in an Orthogonal Frequency Division Multiplexing (OFDM) system, and a transmitter using the same. 2. Description of the Related Art With the ongoing development of the communication industry and the increasing user demands for packet services, there is an increasing need for communication systems that are capable of efficiently providing the packet services. The conventional communication networks, as they have been developed to mainly provide voice services, have narrower data transmission bandwidths and higher service charges. To solve these problems, extensive research is being conducted on Orthogonal Frequency Division Multiplexing (OFDM), which is the typical example of the broadband packet transmission scheme. OFDM, the typical multi-carrier transmission scheme of overlapping multiple orthogonal subcarriers, converts a serial input symbol stream into parallel streams and modulates each of the parallel streams with multiple orthogonal subcarriers before transmission. It is known that the OFDM scheme can provide an efficient platform for high-speed data transmission using its robustness against multipath fading. The Orthogonal Frequency Division Multiple Access (OFDMA) system recently attracting public attention, which is an OFDM-based multiple access system, divides the frequency domain into subchannels each having a plurality of subcarriers, and allocates the subchannels to the users individually to perform resource allocation taking both the time and frequency domains into account, thereby accommodating multiple users with the limited frequency resources. Herein, the use of the term “OFDM system” will be construed to include the OFDMA system. The OFDM scheme, as it divides an input data stream into N S subcarriers before transmission, can reduce N S times the relative multipath spread for the symbol period by increasing the symbol interval N S times. Because transmission of the OFDM symbols is processed on a block-by-block basis, while the OFDM symbols are transmitted over multiple paths, the currently transmitted OFDM symbol may receive interference from the previously transmitted OFDM symbol. As is well known, a scheme for inserting a guard interval between consecutive blocks is used to efficiently cancel the inter-OFDM symbol interference, or Inter-Symbol Interference (ISI). The guard interval is selected to be longer than the expected delay spread so that the multipath component from a previous OFDM symbol will not interfere with a current OFDM symbol. For the OFDM symbols, a Cyclic Prefix (CP) insertion scheme for copying a partial interval of an OFDM symbol and cyclically-concatenating the copy to the guard interval is used to prevent Inter-Channel Interference (ICI). The ‘CP insertion’ refers to an operation of copying a block of, for example, a length N CP at the back of an OFDM symbol and filling the guard interval with the copied block. Even though a subcarrier delay occurs by the CP insertion, an integer period is maintained in a Fast Fourier Transform (FFT) interval, guaranteeing the orthogonality, and only a phase rotation caused by the delay occurs, making it possible to prevent the ICI. In the OFDM system, a symbol modulation scheme parallel-converts serial input data into a number of parallel data streams equal to the number of subcarriers, and modulates each of the parallel-converted data streams with its associated subcarrier. Subcarrier modulation/demodulation can be realized by Discrete Fourier Transform (DFT) and Inverse Discrete Fourier Transform (IDFT). Because the DFT and IDFT have the higher hardware complexity and the higher calculation, they can be realized using Fast Fourier Transform (FFT) and Inverse Fast Fourier Transform (IFFT) algorithms, respectively, to perform the high-speed operation while reducing the complexity and the calculation. The CP insertion is performed in a symbol modulation process of the OFDM system, and for the CP insertion, an output of IFFT is stored in a buffer of a transmitter. In this way, for the CP insertion, the modulation process of the OFDM symbol should store the IFFT output in the buffer until the samples disposed at the back of the IFFT output are output, inevitably causing a delay. In addition, for hardware, there is a need for a buffer for storing all the output of the IFFT. Therefore, a reduction in the delay and the required buffer capacity (or required buffer size), if possible, can improve performance of the transmitter in the OFDM system. That is, for the performance improvement of the transmitter in the OFDM system, there is a need for an apparatus and method capable of reducing the delay and the required buffer capacity. SUMMARY OF THE INVENTION An aspect of the present invention is to address at least the problems and/or disadvantages described herein and to provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide a symbol modulation method and apparatus capable of reducing the delay occurring in a transmitter of an OFDM system, and a transmitter using the same. Another aspect of the present invention is to provide a symbol modulation method and apparatus capable of reducing the buffer size required in a transmitter of an OFDM system, and a transmitter using the same. According to one aspect of the present invention, there is provided a method for modulating a symbol in a transmitter of an Orthogonal Frequency Division Multiplexing (OFDM) system. The symbol modulation method includes multiplying an input stream of an Inverse Fast Fourier Transform (IFFT) unit by a Twiddling factor for circular-shifting the input stream of the IFFT unit by a Cyclic Prefix (CP) length; performing IFFT on the input stream of the IFFT unit, which is multiplied by the Twiddling factor; buffering data corresponding to the CP length beginning from a front of an output stream of the IFFT unit; and generating an OFDM symbol by forward-copying the buffered data to a back of the output stream of the IFFT unit. According to another aspect of the present invention, there is provided an apparatus for modulating a symbol in a transmitter of an Orthogonal Frequency Division Multiplexing (OFDM) system. The symbol modulation method includes a Twiddling factor generator for generating a Twiddling factor used for circular-shifting frequency-domain data by a Cyclic Prefix (CP) length, the frequency-domain data undergoing Inverse Fast Fourier Transform (IFFT); a multiplier for multiplying the frequency-domain data by the Twiddling factor; an IFFT unit for performing IFFT on the frequency-domain data multiplied by the Twiddling factor; and a CP inserter for buffering the IFFT-transformed output stream beginning from a forefront thereof by a CP length, and adding the buffered stream to a back of the output stream. BRIEF DESCRIPTION OF THE DRAWINGS The above and other aspects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which: FIG. 1 illustrates reverse CP copying performed in a general OFDM system; FIG. 2 illustrates a structure of a general OFDM symbol modulator; FIG. 3 illustrates a Signal Flow Graph (SFG) in a Decimation-In-Frequency (DIF) IFFT; FIG. 4 illustrates an SFG in a DIT IFFT; FIG. 5 illustrates the concept of forward CP copying according to an embodiment of the present invention; FIG. 6 illustrates a structure of a transmission apparatus in an OFDM system according to a first embodiment of the present invention; FIG. 7 illustrates a structure of an OFDM symbol modulation apparatus according to the first embodiment of the present invention; FIG. 8 illustrates an OFDM symbol modulation method according to the first embodiment of the present invention; FIG. 9 illustrates a structure of a transmission apparatus in an OFDM system according to a second embodiment of the present invention; FIG. 10 illustrates a structure of an OFDM symbol modulation apparatus according to the second embodiment of the present invention; FIG. 11 illustrates an OFDM symbol modulation method according to the second embodiment of the present invention; FIG. 12 illustrates a structure of an OFDM symbol modulation apparatus according to a third embodiment of the present invention; and FIG. 13 illustrates an OFDM symbol modulation method according to the third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the annexed drawings. In the following description, a detailed description of known functions and configurations incorporated herein has been omitted for clarity and conciseness. A transmitter of an OFDM system includes an OFDM symbol modulator for modulating bit data into an OFDM symbol. The OFDM symbol modulator inserts a CP for ISI prevention into an IFFT output, and buffers the IFFT output in the CP insertion process. The increase in the required buffer capacity and/or the delay occurring during CP insertion in the OFDM symbol modulator are caused by the samples of an IFFT output corresponding to the CP being output at the back of an N FFT -symbol stream in terms of time. Therefore, the present invention provides a technology for allowing the samples corresponding to the CP to be output from the beginning of an N FFT -symbol stream output from IFFT, thereby reducing the required buffer capacity and also preventing the delay occurring during CP insertion. In addition, the present invention provides a technology for performing bit-reversed (re)ordering for CP insertion at the front stage of IFFT in a parallel way, thereby further reducing the delay occurring during CP insertion. For a better understanding of the present invention, a detailed description will now be made of (i) the type of an FFT algorithm applied to the general OFDM symbol modulator, (ii) the reasons why the delay occurs during CP insertion, and (iii) the reasons why more than two buffers are required for the general OFDM symbol modulator. First, DFT and IDFT are defined by Equation (1) and Equation (2), respectively. X ( k )=Σ n=0 N−1 x ( n )exp(− j 2 πnk/N )  (1) x ⁡ ( n ) = 1 N ⁢ ∑ k = 0 N - 1 ⁢ X ⁡ ( k ) ⁢ exp ⁡ ( j2π ⁢ ⁢ nk ⁢ / ⁢ N ) ( 2 ) Actually, the DFT and IDFT are realized using an FFT algorithm to perform high-speed operations while reducing the hardware calculations. A size N FFT of the FFT is equal to the total number N s of subcarriers. The FFT algorithm can be classified into a Decimation-In-Frequency (DIF) scheme and Decimation-In-Time (DIT) scheme. During the actual hardware design of the FFT, to reduce the hardware complexity, it is preferable to use a Pipeline FFT rather than realizing the FFT in a parallel way according to a Signal Flow Graph (SFG) of the FFT. The Pipeline FFT is chiefly used for an application field requiring high performance. This is because the Pipeline FFT, compared to the FFT realized according to the SFG, has lower hardware complexity, has a regular FFT architecture, has simpler control, and enables serial input and serial output. As shown in FIG. 1 , for OFDM symbol modulation, the general OFDM/OFDMA scheme reverse-copies the back 107 of a total of N FFT samples output from IFFT back to the forefront (or head) of IFFT output 103 , and attaches the copy to a guard interval 105 . The CP copied to the guard interval 105 uses N CP samples in the backmost portion of the OFDM symbol 101 . The general OFDM symbol modulator that uses the reverse copy scheme for CP insertion has the structure of FIG. 2 . In the DIF scheme-based IFFT 201 (hereinafter referred to as ‘DIF IFFT’) shown in FIG. 2 , while the input bits are ordered, the output bits are bit-reversed ordered. On the contrary, in the DIT scheme-based IFFT (hereinafter referred to as ‘DIT IFFT’), while the input bits are bit-reversed ordered, the output bits are ordered. This is because of the butterfly structure of the IFFT. For example, when the total number of N FFT samples of the IFFT is 8, DIF SFG is as shown in FIG. 3 and DIT SFG is as shown in FIG. 4 . In FIGS. 3 and 4 , reference numerals 301 and 401 indicate inputs of DIF IFFT and DIT IFFT, respectively, and reference numerals 303 and 403 indicate outputs of DIF IFFT and DIT IFFT, respectively. It can be appreciated that for DIF IFFT, the output bits are bit-reversed ordered as shown in FIG. 3 , and for DIT IFFT, the input bits are bit-reversed ordered as shown in FIG. 4 . Therefore, the OFDM symbol modulator needs a bit-reversed ordering unit 203 for reordering the bit data bit-reversed ordered at one of input/output ends of IFFT as shown in FIG. 2 . The ‘bit-reversed ordering’ refers to an operation in which when a number n is expressed in binary format, bits of the binary number are ordered in a reverse order as shown in Table 1. For example, for input bits ‘001’, their bit-reversed ordered output bits are ‘100’. TABLE 1 Bit reversed order Bit reversed order Order (decimal) Order (binary) (binary) (decimal) 0 000 000 0 1 001 100 4 2 010 010 2 3 011 110 6 4 100 001 1 5 101 101 5 6 110 011 3 7 111 111 7 Turning back to the description of FIG. 2 , because the inputs of DIF IFFT are allowed to be sequentially input to DIF IFFT but the outputs are output from DIF IFFT after undergoing bit-reversed ordering, there is a need for an IFFT output memory for bit reordering, and the output memory is prepared in the bit-reversed ordering unit 203 . Similarly, because the inputs of DIT IFFT are input to DIT IFFT after undergoing bit-reversed ordering, there is a need for an IFFT input memory for bit-reversed ordering. To this end, a bit-reversed ordering unit (not shown) serving as the input memory is prepared in the front stage of the DIT IFFT. A CP inserter 205 of FIG. 2 , because it should reverse-copy N CP samples at the back of an IFFT output, needs at least two buffers (memories) having an OFDM symbol size. In the conventional scheme, to complete one OFDM symbol, a delay occurs until N CP samples are output at the back of an IFFT output, and a total of N FFT samples of the IFFT output are stored in a first symbol buffer 205 c in the CP inserter 205 . In terms of the delay, because for reverse copy, the CP inserter 205 cannot output data to the next block until the data of N FFT samples are input to the buffer, the time delay corresponding to the N FFT samples occurs. Because the CP insertion process occurs every symbol interval, data input from the IFFT 201 and data output to a filter (not shown), or the next stage, should be simultaneously performed in the CP inserter 205 . Therefore, the OFDM symbol modulator 200 of FIG. 2 needs at least two buffers having the size of the IFFT 201 , such as the first symbol buffer 205 c for receiving the data output from the IFFT 201 and a second symbol buffer 205 d for outputting the data to the filter, and first and second switches 205 a and 205 b each switch inputs and outputs to/from the first and second symbol buffers 205 c and 205 d . That is, in the input/output scheme applied in FIG. 2 , while the first symbol buffer 205 c is filled up, data of the second symbol buffer 205 d is output and switched by the first and second symbol buffers 205 c and 205 d in the next symbol interval. As described above, the output end of DIF IFFT needs an operation of bit-reordering the output bit stream, and the input end of DIT IFFT needs an operation of bit-reordering the input bit stream. The two methods both need a buffer for bit reordering, and in terms of the delay, the OFDM symbol modulator cannot output the data to the next block until the data of N FFT IFFT samples is received, causing the time delay corresponding to the N FFT sample. As to the reason why the required buffer capacity and the delay happens, when the conventional CP insertion scheme is used, the samples corresponding to the CP are output at the back of an N FFT -symbol stream in terms of time. Therefore, in order to add the CP, it is necessary to buffer the entire IFFT output stream, and further, it is necessary to copy samples corresponding to the CP in the entire IFFT output stream and reverse-add the copied samples. In addition, the bit-reversed ordering process is needed for the inputting/outputting of the IFFT, causing the time delay. Therefore, proposed herein is a new scheme for allowing the value corresponding to the CP to be output beginning from the front of a total of N FFT samples during the output of the IFFT, thereby reducing the delay occurring during CP insertion and the required buffer capacity. If the bit-reversed ordering performed during the inputting/outputting of the IFFT is performed in parallel, the delay occurring during CP insertion and the required buffer capacity can be further reduced, and the hardware complexity can also be reduced. With reference to FIGS. 5 to 13 , a detailed description will now be made of embodiments of the present invention. The embodiments of the present invention will be described in light of 3 viewpoints. After the basic concept of the present invention is first described with reference to FIG. 5 , a first embodiment for forward-copying a CP for an output of the DIT IFFT to thereby reduce the required buffer capacity and the delay occurring during CP insertion will be described with reference to FIGS. 6 to 8 . Thereafter, a second embodiment for parallel-performing not only the forward CP copying but also the bit-reversed ordering required at the input/output ends of the DIT IFFT to thereby further reduce the delay occurring during CP insertion and the required buffer capacity will be described with reference to FIGS. 9 to 11 , and a third embodiment for performing forward CP copying on the output of the DIF IFFT to thereby reduce the required buffer capacity and the delay occurring during CP insertion will be described with reference to FIGS. 12 and 13 . FIG. 5 illustrates the concept of forward CP copying according to an embodiment of the present invention. IFFT, a realization algorithm designed to quickly perform the IDFT calculation fast, follows all the basic characteristics of the IDFT. For example, the intact circular shift characteristic and periodicity of the IDFT can be applied even in the IFFT. The circular shift characteristic and periodicity of the IDFT are as follows. Equation (3) indicates the circular shift characteristic of the IDFT, and Equation (4) indicates the periodicity of the IDFT. X[k]=X[k+N]   (3) where N denotes the number of points of the IDFT. y[n]=x [( n−m )mod N ] Y[k]=W N −mk X[k],m εZ, 0 ≦n≦N   (4) where W N n denotes a Twiddling factor for the DFT calculation, and W N n =exp(j2πn/N). If the characteristics of Equation (3) and Equation (4) are applied to the IFFT-based OFDM modulation process, the result of Equation (5) can be derived. If ⁢ ⁢ F - 1 ⁡ ( X ⁡ [ k ] ) = x ⁡ [ n ] , then ⁢ ⁢ F - 1 ⁡ ( W N FFT - kN CP * X ⁡ [ k ] ) = ⁢ F - 1 ⁡ ( exp ⁡ ( j2π ⁢ ⁢ N CP / N FFT ) * X ⁡ [ k ] ) = ⁢ x ⁡ [ ( n - N CP ) ⁢ ⁢ mod ⁢ ⁢ N FFT ] = ⁢ x ⁡ [ ( n - N CP + N FFT ) ⁢ ⁢ mod ⁢ ⁢ N FFT ] ( 5 ) where F 1 denotes the IFFT calculation, and k and n denote index values of an input stream and an output stream of the IFFT, respectively, and have an integer value between 0 to N FFT −1. Further, N CP denotes a length of a CP sample, and N FFT denotes an FFT size and is equal to the number of subcarriers. When the IFFT is performed by multiplying the input stream of the IFFT by a Twiddling factor corresponding to the length of a CP sample, the output of the IFFT undergoes circular rotation (or circular shift). In addition, when a value N CP is applied to the circular shift as shown in Equation (5), it is possible to obtain the result that the part corresponding to the CP value is first output from the IFFT and the remaining values are output following the corresponding part. As a result, when compared to the conventional scheme, the CP that should be copied last is first output by circular shift. Therefore, with the use of Equation (5), it is possible to forward-copy the CP part from the front of an IFFT output as shown in FIG. 5 . In FIG. 5 , an output 503 of the IFFT is assumed to be circular-shifted by a sample length N CP of a CP interval using the Twiddling factor. Under this assumption, the present invention first buffers the front of an OFDM symbol 501 where data of a CP interval 507 in the entire output 503 of the IFFT is located. Thereafter, if the output 503 of the IFFT is completed, the invention forward-copies the buffered data of the CP interval 507 and attaches it to the back 505 of the OFDM symbol. By circular-rotating the IFFT output by the CP interval using the Twiddling factor and then forward-copying the result as described above, the new scheme can insert a CP into an OFDM symbol without buffering all samples of the IFFT output like that of the conventional scheme described in FIG. 1 , thereby contributing to a reduction in the buffer capacity (or buffer size) required for the OFDM symbol modulator. In addition, the new scheme can perform CP insertion without waiting until all samples of IFFT are buffered like that of the conventional scheme, thereby contributing to a reduction in the delay occurring during CP insertion. A detailed description will now be made of the first embodiment to the third embodiment of the present invention, all of which use the forward CP copying. First Embodiment FIG. 6 illustrates a structure of a transmission apparatus in an OFDM system according to the first embodiment of the present invention. A transmission apparatus 600 of FIG. 6 includes an encoder 601 , a mapper 603 , a subcarrier allocator 605 , a scrambling code generator 607 , a multiplier 609 , an OFDM symbol modulator 611 , a filter 613 , a Digital-to-Analog Converter (DAC) 615 , a Radio Frequency (RF) processor 617 , and an antenna 619 . Among the elements of FIG. 6 , the remaining elements except for the OFDM symbol modulator 611 are equal to the corresponding elements of the general OFDM transmitter for encoding bit data, performing symbol mapping thereon, allocating subcarriers to the mapped data, spreading scrambling codes by multiplying, filtering an OFDM symbol, and transmitting it with a radio signal, so a detailed description thereof will be omitted herein. The OFDM symbol modulator 611 not only performs IFFT on the input data but also performs forward CP copying thereon according to the present invention in the CP insertion process. FIG. 7 illustrates a structure of an OFDM symbol modulation apparatus according to the first embodiment of the present invention. The apparatus shown in FIG. 7 indicates the OFDM symbol modulator 611 of FIG. 6 . The apparatus of FIG. 7 is an embodiment using DIT IFFT 707 , which performs forward CP copying in such a manner that input bits of the IFFT undergo bit-reversed ordering. In FIG. 7 , a Twiddling factor generator 701 sequentially outputs Twiddling factors that should be multiplied by data X[k] in the frequency domain by a multiplier 703 . According to the characteristics of the Twiddling factors, the number of Twiddling factors that should be generated depending on the value k of the input data X[k] is limited to, for example, N FFT /N CP where N FFT denotes the total number (or length) of samples of an IFFT output, and N CP denotes the number (or length) of samples of a CP interval. If indexes of the limited number of Twiddling factors are defined as a ‘Twiddling factor number’, the Twiddling factor multiplied by the input bits according to the Twiddling factor number is expressed as Equation (6). Twiddling factor (Twiddling factor number)=exp(− j 2π*Twiddling factor number* N CP /N FFT )  (6) In addition, the Twiddling factor number according to the index k of the input data X[k] has a relationship of Equation (7). Twiddling factor number( k )=( k mod( N FFT /N CP )), k= 0,1,2 , . . . N FFT −1  (7) For example, if a CP length is assumed to be ⅛ of the FFT size like in the WiMAX standard, the number of Twiddling factor numbers is limited to 8, and the Twiddling factors that should be multiplied according to the 8 Twiddling factor numbers are as shown in Table 2. TABLE 2 Index Twiddling factor number Twiddling factor If(k mod 8) = 0 0 1 If(k mod 8) = 1 1 1 2 ⁢ ( - 1 - i ) If(k mod 8) = 2 2 −i If(k mod 8) = 3 3 1 2 ⁢ ( 1 - i ) If(k mod 8) = 4 4 −1 If(k mod 8) = 5 5 1 2 ⁢ ( - 1 + i ) If(k mod 8) = 6 6 i If(k mod 8) = 7 7 1 2 ⁢ ( 1 + i ) The Twiddling factor multiplied by an input stream to IFFT 707 in the multiplier 703 of FIG. 7 is set such that an output of IFFT 707 is circular-shifted by a length of a CP sample. A bit-reversed ordering unit 705 bit-reversed orders an IFFT input multiplied by the Twiddling factor, and the IFFT 707 performs IFFT according to the DIT scheme. Here, an IFFT output, compared to the general IFFT output, is the data circular-shifted by a sample length N CP of the CP interval. A CP inserter 709 of FIG. 7 includes first and second switches 709 a and 709 b , and a CP buffer 709 c . The first switch 709 a performs switching so as to store the data of only the CP interval in the CP buffer 709 c at the front of an IFFT output stream while outputting an IFFT output to the second switch 709 b . The second switch 709 b performs switching so as to output the IFFT output delivered from the first switch 709 a to a filter (indicated by reference numeral 613 of FIG. 6 ), or the next stage, and after the output of IFFT 707 is completed in the corresponding block, outputs the data stored in the CP buffer 709 c to the filter 613 following the corresponding output. The switching and buffering operation of the CP inserter 709 can be performed by an undepicted controller. FIG. 8 illustrates an OFDM symbol modulation method according to the first embodiment of the present invention. The method of FIG. 8 will be described with reference to FIG. 7 . In step 801 , a Twiddling factor generator 701 generates a Twiddling factor for forward CP copying, and multiplies the generated Twiddling factor by a transmission signal being input to an IFFT 707 by means of a multiplier 703 . In step 803 , a bit-reversed ordering unit 705 bit-reverse orders the transmission signal multiplied by the Twiddling factor, and outputs the resulting transmission signal to the IFFT 707 . In step 805 , the IFFT 707 performs the DIT IFFT on the bit-reversed ordered transmission signal, and outputs the IFFT data circular—shifted by a CP length. A CP inserter 709 buffers a CP part at the front of the IFFT output in step 807 , and attaches the buffered CP part to the back of the IFFT output in step 809 . According to the first embodiment, the new scheme can insert a CP into an OFDM symbol without the need for buffering all of the samples of the IFFT output like that of the conventional scheme, and can also perform CP insertion without waiting until all samples of the IFFT are buffered. When the DIT IFFT is used as described in the first embodiment, it is possible to parallel-perform the bit-reversed ordering and circular shift required in the IFFT input at the front stage of IFFT. In this case, the IFFT output can be used. Next, the second embodiment will propose a scheme of performing bit-reversed ordering and circular shift for an IFFT input at the front stage of IFFT. Second Embodiment FIG. 9 illustrates a structure of a transmission apparatus in an OFDM system according to the second embodiment of the present invention. A transmission apparatus 900 of FIG. 9 includes an encoder 901 , a mapper 903 , a subcarrier allocator 905 , a scrambling code generator 907 , a Twiddling factor generator 909 , a multiplier 910 , an OFDM symbol modulator 911 , a filter 913 , a DAC 915 , an RF processor 917 , and an antenna 919 . In the transmission apparatus of FIG. 9 , its basic operation of encoding bit data, performing symbol mapping thereon, allocating subcarriers to the mapped data, spreading scrambling codes by multiplying, filtering an OFDM symbol, and transmitting it with a radio signal is equal to the operation of the general OFDM transmitter, so a detailed description thereof will be omitted herein. However, according to the present invention, the transmission apparatus of FIG. 9 includes, at the front stage of the OFDM symbol modulator 911 , the Twiddling factor generator 909 for generating Twiddling factors for circular shift, and further includes bit-reversed ordering units 905 a , 907 a and 909 a for bit-reversed ordering outputs of the subcarrier allocator 905 , the scrambling code generator 907 and the Twiddling factor generator 909 , respectively. Among the bit-reversed ordering units 905 a , 907 a and 909 a , the bit-reversed ordering unit 907 a included in the scrambling code generator 907 and the bit-reversed ordering unit 909 a included in the Twiddling factor generator 909 may not be needed in the actual configuration, because the scrambling code generator 907 can be designed such that it generates scrambling codes to be multiplied by the bit-reversed ordered transmission signal during the generation of the scrambling codes. Similarly, the Twiddling factor generator 909 can also be configured such that it generates Twiddling factors to be multiplied by the bit-reversed ordered transmission signal during the generation of the Twiddling factors. The OFDM symbol modulator 911 performs the IFFT on the input data and also performs the forward CP copying on the input data in the CP insertion process according to the present invention. By parallel-performing forward CP copying and bit-reversed ordering on the transmission signal being input to the IFFT at the front stage of the OFDM symbol modulator 911 according to the second embodiment of FIG. 2 , the new scheme can further reduce the buffer capacity required in the OFDM symbol modulator 911 and the delay occurring during CP insertion. In the general OFDM transmitter, because the element such as the subcarrier allocator 905 already has an internal buffer for performing its corresponding operation, the inclusion of the bit-reversed ordering unit 905 a in FIG. 9 may not need a separate memory for bit-reversed ordering of the transmission signal, because the OFDM transmitter only needs to simply bit-reverse order an allocation address for the input data during subcarrier allocation. To this end, for subcarrier allocation, the subcarrier allocator 905 of FIG. 9 can use the allocation scheme in which bit-reversed ordering for input data has already been reflected. Equation (8) defines an allocation algorithm where the bit-reversed ordering for input data has already been reflected in the subcarrier allocator 905 of FIG. 9 . Allocated data ( k ′)=bit reversed (Allocated data ( k )), k =0,1,2 , . . . ,N FFT −1 where k ′=bit reversed( k ), k′= 0,1,2, . . . N FFT −1  (8) Similarly, the multiplier 910 where the Twiddling factors are multiplied can be designed using the existing multiplier (indicated by reference numeral 609 of FIG. 6 ) where the scrambling codes are multiplied. In the second embodiment of FIG. 9 , because the data bit-reversed ordered by the subcarrier allocator 905 is output, the scrambling code generator 907 and the Twiddling factor generator 909 also output the scrambling codes and the Twiddling factors, respectively, in which the bit-reversed ordering has already been reflected according to the following method. The bit-reversed ordering method for the Twiddling factor will first be described. While the Twiddling factor number based on the index k of the Twiddling factor can be expressed as Equation (7) in the first embodiment, the Twiddling factor number of the bit-reversed ordering-reflected Twiddling factor can be expressed as Equation (9) for the index k′ of the bit-reversed ordered input data. Twiddling factor number( k ′)=bit reversed(round( k′/N CP )) where k ′=bit reversed( k ), k′= 0,1,2, . . . , N FFT −1  (9) where ‘round’ refers to a rounding operator. The Twiddling factor determined according to the Twiddling factor number in Equation (9) is equal to that determined before the bit-reversed ordering is applied, and is determined as shown in Equation (6). For example, if a ratio of N FFT to N CP is 8:1 like in the WiMAX standard, the Twiddling factors generated by the Twiddling factor generator 909 of FIG. 9 according to the index k′ of the bit-reversed ordered input data are as shown in Table 3. TABLE 3 k′ (bit reversed reordering index) Twiddling factor number Twiddling factor 0~N CP − 1 0  1 N CP ~2 * N CP − 1 4 −1 2 * N CP ~3 * N CP − 1 2 −i 3 * N CP ~4 * N CP − 1 6  i 4 * N CP ~5 * N CP − 1 1 1 2 ⁢ ( - 1 - i ) 5 * N CP ~6 * N CP − 1 5 1 2 ⁢ ( - 1 + i ) 6 * N CP ~7 * N CP − 1 3 1 2 ⁢ ( 1 - i ) 7 * N CP ~8 * N CP − 1 7 1 2 ⁢ ( 1 + i ) The scrambling codes generated by the scrambling code generator 907 of FIG. 9 are also bit-reversed ordered and then multiplied by the bit-reversed ordered input data, and a description of the bit-reversed ordering method will be described below. The bit-reversed ordering method can previously generate scrambling codes according to the index k′ of the bit-reversed ordered data using the corresponding scrambling seed, and store the generated scrambling codes in the memory for later use. That is, the bit-reversed ordering units 905 a , 907 a and 909 a of FIG. 9 can be realized by means of the memories used by the subcarrier allocator 905 , the scrambling code generator 907 and the Twiddling factor generator 909 , respectively. As to the memory used by the scrambling code generator 907 , it can be understood that because the scrambling code is 1-bit data, its required memory capacity is very low. The scrambling codes are output in order of bit-reversed ordering made according to Equation (10). Scrambling code( k ′)=bit reversed(scrambling code(scrambling seed, k )), k= 0,1,2 , . . . N FFT −1 where k ′=bit reversed( k ), k′= 0,1,2 , . . . ,N FFT −1  (10) FIG. 10 illustrates a structure of an OFDM symbol modulation apparatus according to the second embodiment of the present invention. The apparatus shown in FIG. 10 indicates the OFDM symbol modulator 911 of FIG. 9 . In the OFDM symbol modulation apparatus 1000 of FIG. 10 , the input data is received after it underwent bit-reversed ordering in a parallel way at its front stage as described above. IFFT 1001 performs IFFT on the bit-reversed ordered input data according to the DIT scheme. The IFFT output, compared to the general IFFT output, is the data circular-shifted by a sample length N CP of a CP interval. A CP inserter 1003 of FIG. 10 includes first and second switches 1003 a and 1003 b , and a CP buffer 1003 c , and its operation is equal to that of the CP inserter 709 of FIG. 7 , so a detailed description thereof will be omitted. FIG. 11 illustrates an OFDM symbol modulation method according to the second embodiment of the present invention. The method of FIG. 11 will be described with reference to FIG. 10 . In step 1101 , a front stage of IFFT 1001 multiplies the bit-reversed ordered input transmission signal by a Twiddling factor for forward CP copying. Thereafter, in step 1103 , the IFFT 1001 performs the DIT IFFT on the bit-reversed ordered transmission signal, and outputs the IFFT data circular-shifted by a CP length. A CP inserter 1003 buffers a CP part at the front of the IFFT output in step 1105 , and attaches the buffered CP part to the back of the IFFT output in step 1107 . According to the second embodiment, the new scheme can insert a CP into an OFDM symbol without the need of buffering all of the samples of the IFFT output like that of the conventional scheme, and can also perform CP insertion without waiting until all of the samples of the IFFT are buffered. In addition, the new scheme can perform bit-reversed ordering and circular shift on the IFFT input at the front stage of the IFFT, contributing to a further reduction in the required buffer capacity and the delay. Although the foregoing description of the first embodiment and the second embodiment is directed to the case where the present invention is applied to the DIT IFFT, the third embodiment will propose a scheme of performing forward CP copying for the DIF IFFT, thereby contributing to a reduction in the required buffer capacity and the delay during CP insertion. Third Embodiment In the third embodiment, the OFDM transmission apparatus can use the intact structure of FIG. 9 described in the first embodiment, after simply modifying only the structure of the OFDM symbol modulator as shown in FIG. 12 . FIG. 12 illustrates a structure of an OFDM symbol modulation apparatus according to the third embodiment of the present invention. In the OFDM symbol modulation apparatus 1200 of FIG. 12 , a Twiddling factor generator 1201 sequentially outputs Twiddling factors that should be multiplied by the frequency-domain data by means of a multiplier 1203 . Here, the Twiddling factors are generated in the manner described in the first embodiment. The Twiddling factor multiplied by the input stream of IFFT 1205 is set such that the output of IFFT 1205 is circular-shifted by a length of a CP sample. However, while the first embodiment bit-reversed orders an input of the IFFT using the DIT IFFT, the third embodiment uses the DIF IFFT for the bit-reversed ordering, so the input of the IFFT is directly input to the IFFT 1205 without undergoing the bit-reversed ordering process. In FIG. 12 , the IFFT 1205 performs the IFFT according to the DIF scheme. Here, the IFFT output, compared to the general IFFT output, is the data circular-shifted by a sample length N CP of a CP interval. A bit-reversed ordering unit 1207 bit-reversed orders the circular-shifted IFFT output. A CP inserter 1209 of FIG. 12 includes first and second switches 1209 a and 1209 b , and a CP buffer 1209 c , and its operation is equal to that of the CP inserter 709 of FIG. 7 , so a detailed description thereof will be omitted. FIG. 13 illustrates an OFDM symbol modulation method according to the third embodiment of the present invention. The method of FIG. 13 will be described with reference to FIG. 12 . In step 1301 , a Twiddling factor generator 1201 generates a Twiddling factor for forward CP copying, and multiplies the generated Twiddling factor by a transmission signal being input to IFFT 1205 by means of a multiplier 1203 . In step 1303 , the IFFT 1205 performs the DIF IFFT, and outputs the IFFT data circular-shifted by a CP length. In step 1305 , a bit-reversed ordering unit 1207 bit-reversed orders the circular-shifted IFFT output, and outputs the result to a CP inserter 1209 . As for the DIF IFFT, its output undergoes bit-reversed ordering before being output. Therefore, if the bit-reversed ordering unit 1207 performs bit-reversed ordering in step 1305 , the IFFT output is reordered in its original bit order. Thereafter, the CP inserter 1209 buffers a CP part at the front of an IFFT output in step 1307 , and attaches the buffered CP part to the back of the IFFT output in step 1309 . According to the first embodiment to the third embodiment of the present invention, because the value corresponding to a CP in an IFFT output is output from the beginning, the new scheme can immediately forward the value output from the IFFT to the next stage without the need to store all of the samples of an OFDM symbol in the buffer. Therefore, the new scheme, compared to the conventional OFDM symbol modulation scheme, can reduce the delay by an N FFT -sample length. In addition, the conventional scheme, as it should store the entire OFDM symbol, uses at least two N FFT -size buffers for the CP inserter, whereas the new OFDM symbol modulation scheme proposed by the present invention can reduce the required buffer capacity because the CP inserter uses only one CP-size buffer as the new scheme needs only to store in the CP buffer the value corresponding to the first CP interval in the IFFT output. For example, assuming that 1024-point FFT and a 128-sample CP are used and the number of IFFT input/output bits is 16 for each of the I and Q channels, the buffer reduction ratio required for the OFDM symbol modulator is as follows: Conventional IFFT Output Buffer Decrement=1024 samples*32 bits*2=65536 bits CP Buffer Increment=128 samples*32 bits*1=4096 bits Scrambler Buffer Increment=1024 samples*1 bit*1=1024 bits Buffer (Memory) Decrement Ratio=(4096+1024−65536)/65536=92% Decrement As a result, the proposed scheme, compared to the conventional scheme, can reduce about 92% of the required buffer capacity. As is apparent from the foregoing description, the present invention can reduce the delay and the required buffer capacity occurring in the OFDM transmitter that performs CP insertion in the OFDM symbol modulation process, thereby contributing to improvement of the performance of the OFDM transmitter. In addition, the present invention can reduce the data transmission preparation time at the OFDM transmitter, thus contributing to an increase in the timing margin and a decrease in the hardware complexity of the transmitter. While the invention has been shown and described with reference to a certain preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
A method for modulating a symbol in a transmitter of an Orthogonal Frequency Division Multiplexing (OFDM) system. The symbol modulation method includes multiplying an input stream of an Inverse Fast Fourier Transform (IFFT) unit by a Twiddling factor for circular-shifting the input stream of the IFFT unit by a Cyclic Prefix (CP) length; performing IFFT on the input stream of the IFFT unit, which is multiplied by the Twiddling factor; buffering data corresponding to the CP length beginning from a front of an output stream of the IFFT unit; and generating an OFDM symbol by forward-copying the buffered data to a back of the output stream of the IFFT unit.
Summarize the key points of the given patent document.
[ "PRIORITY This application claims priority under 35 U.S.C. §119(a) to a Korean Patent Application filed in the Korean Intellectual Property Office on Dec. 28, 2006 and assigned Ser.", "No. 2006-137082, the disclosure of which is incorporated herein by reference.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates generally to a method and apparatus for modulating symbols in a wireless communication system, and in particular, to a method and apparatus for efficiently modulating symbols in an Orthogonal Frequency Division Multiplexing (OFDM) system, and a transmitter using the same.", "Description of the Related Art With the ongoing development of the communication industry and the increasing user demands for packet services, there is an increasing need for communication systems that are capable of efficiently providing the packet services.", "The conventional communication networks, as they have been developed to mainly provide voice services, have narrower data transmission bandwidths and higher service charges.", "To solve these problems, extensive research is being conducted on Orthogonal Frequency Division Multiplexing (OFDM), which is the typical example of the broadband packet transmission scheme.", "OFDM, the typical multi-carrier transmission scheme of overlapping multiple orthogonal subcarriers, converts a serial input symbol stream into parallel streams and modulates each of the parallel streams with multiple orthogonal subcarriers before transmission.", "It is known that the OFDM scheme can provide an efficient platform for high-speed data transmission using its robustness against multipath fading.", "The Orthogonal Frequency Division Multiple Access (OFDMA) system recently attracting public attention, which is an OFDM-based multiple access system, divides the frequency domain into subchannels each having a plurality of subcarriers, and allocates the subchannels to the users individually to perform resource allocation taking both the time and frequency domains into account, thereby accommodating multiple users with the limited frequency resources.", "Herein, the use of the term “OFDM system”", "will be construed to include the OFDMA system.", "The OFDM scheme, as it divides an input data stream into N S subcarriers before transmission, can reduce N S times the relative multipath spread for the symbol period by increasing the symbol interval N S times.", "Because transmission of the OFDM symbols is processed on a block-by-block basis, while the OFDM symbols are transmitted over multiple paths, the currently transmitted OFDM symbol may receive interference from the previously transmitted OFDM symbol.", "As is well known, a scheme for inserting a guard interval between consecutive blocks is used to efficiently cancel the inter-OFDM symbol interference, or Inter-Symbol Interference (ISI).", "The guard interval is selected to be longer than the expected delay spread so that the multipath component from a previous OFDM symbol will not interfere with a current OFDM symbol.", "For the OFDM symbols, a Cyclic Prefix (CP) insertion scheme for copying a partial interval of an OFDM symbol and cyclically-concatenating the copy to the guard interval is used to prevent Inter-Channel Interference (ICI).", "The ‘CP insertion’ refers to an operation of copying a block of, for example, a length N CP at the back of an OFDM symbol and filling the guard interval with the copied block.", "Even though a subcarrier delay occurs by the CP insertion, an integer period is maintained in a Fast Fourier Transform (FFT) interval, guaranteeing the orthogonality, and only a phase rotation caused by the delay occurs, making it possible to prevent the ICI.", "In the OFDM system, a symbol modulation scheme parallel-converts serial input data into a number of parallel data streams equal to the number of subcarriers, and modulates each of the parallel-converted data streams with its associated subcarrier.", "Subcarrier modulation/demodulation can be realized by Discrete Fourier Transform (DFT) and Inverse Discrete Fourier Transform (IDFT).", "Because the DFT and IDFT have the higher hardware complexity and the higher calculation, they can be realized using Fast Fourier Transform (FFT) and Inverse Fast Fourier Transform (IFFT) algorithms, respectively, to perform the high-speed operation while reducing the complexity and the calculation.", "The CP insertion is performed in a symbol modulation process of the OFDM system, and for the CP insertion, an output of IFFT is stored in a buffer of a transmitter.", "In this way, for the CP insertion, the modulation process of the OFDM symbol should store the IFFT output in the buffer until the samples disposed at the back of the IFFT output are output, inevitably causing a delay.", "In addition, for hardware, there is a need for a buffer for storing all the output of the IFFT.", "Therefore, a reduction in the delay and the required buffer capacity (or required buffer size), if possible, can improve performance of the transmitter in the OFDM system.", "That is, for the performance improvement of the transmitter in the OFDM system, there is a need for an apparatus and method capable of reducing the delay and the required buffer capacity.", "SUMMARY OF THE INVENTION An aspect of the present invention is to address at least the problems and/or disadvantages described herein and to provide at least the advantages described below.", "Accordingly, an aspect of the present invention is to provide a symbol modulation method and apparatus capable of reducing the delay occurring in a transmitter of an OFDM system, and a transmitter using the same.", "Another aspect of the present invention is to provide a symbol modulation method and apparatus capable of reducing the buffer size required in a transmitter of an OFDM system, and a transmitter using the same.", "According to one aspect of the present invention, there is provided a method for modulating a symbol in a transmitter of an Orthogonal Frequency Division Multiplexing (OFDM) system.", "The symbol modulation method includes multiplying an input stream of an Inverse Fast Fourier Transform (IFFT) unit by a Twiddling factor for circular-shifting the input stream of the IFFT unit by a Cyclic Prefix (CP) length;", "performing IFFT on the input stream of the IFFT unit, which is multiplied by the Twiddling factor;", "buffering data corresponding to the CP length beginning from a front of an output stream of the IFFT unit;", "and generating an OFDM symbol by forward-copying the buffered data to a back of the output stream of the IFFT unit.", "According to another aspect of the present invention, there is provided an apparatus for modulating a symbol in a transmitter of an Orthogonal Frequency Division Multiplexing (OFDM) system.", "The symbol modulation method includes a Twiddling factor generator for generating a Twiddling factor used for circular-shifting frequency-domain data by a Cyclic Prefix (CP) length, the frequency-domain data undergoing Inverse Fast Fourier Transform (IFFT);", "a multiplier for multiplying the frequency-domain data by the Twiddling factor;", "an IFFT unit for performing IFFT on the frequency-domain data multiplied by the Twiddling factor;", "and a CP inserter for buffering the IFFT-transformed output stream beginning from a forefront thereof by a CP length, and adding the buffered stream to a back of the output stream.", "BRIEF DESCRIPTION OF THE DRAWINGS The above and other aspects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which: FIG. 1 illustrates reverse CP copying performed in a general OFDM system;", "FIG. 2 illustrates a structure of a general OFDM symbol modulator;", "FIG. 3 illustrates a Signal Flow Graph (SFG) in a Decimation-In-Frequency (DIF) IFFT;", "FIG. 4 illustrates an SFG in a DIT IFFT;", "FIG. 5 illustrates the concept of forward CP copying according to an embodiment of the present invention;", "FIG. 6 illustrates a structure of a transmission apparatus in an OFDM system according to a first embodiment of the present invention;", "FIG. 7 illustrates a structure of an OFDM symbol modulation apparatus according to the first embodiment of the present invention;", "FIG. 8 illustrates an OFDM symbol modulation method according to the first embodiment of the present invention;", "FIG. 9 illustrates a structure of a transmission apparatus in an OFDM system according to a second embodiment of the present invention;", "FIG. 10 illustrates a structure of an OFDM symbol modulation apparatus according to the second embodiment of the present invention;", "FIG. 11 illustrates an OFDM symbol modulation method according to the second embodiment of the present invention;", "FIG. 12 illustrates a structure of an OFDM symbol modulation apparatus according to a third embodiment of the present invention;", "and FIG. 13 illustrates an OFDM symbol modulation method according to the third embodiment of the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the annexed drawings.", "In the following description, a detailed description of known functions and configurations incorporated herein has been omitted for clarity and conciseness.", "A transmitter of an OFDM system includes an OFDM symbol modulator for modulating bit data into an OFDM symbol.", "The OFDM symbol modulator inserts a CP for ISI prevention into an IFFT output, and buffers the IFFT output in the CP insertion process.", "The increase in the required buffer capacity and/or the delay occurring during CP insertion in the OFDM symbol modulator are caused by the samples of an IFFT output corresponding to the CP being output at the back of an N FFT -symbol stream in terms of time.", "Therefore, the present invention provides a technology for allowing the samples corresponding to the CP to be output from the beginning of an N FFT -symbol stream output from IFFT, thereby reducing the required buffer capacity and also preventing the delay occurring during CP insertion.", "In addition, the present invention provides a technology for performing bit-reversed (re)ordering for CP insertion at the front stage of IFFT in a parallel way, thereby further reducing the delay occurring during CP insertion.", "For a better understanding of the present invention, a detailed description will now be made of (i) the type of an FFT algorithm applied to the general OFDM symbol modulator, (ii) the reasons why the delay occurs during CP insertion, and (iii) the reasons why more than two buffers are required for the general OFDM symbol modulator.", "First, DFT and IDFT are defined by Equation (1) and Equation (2), respectively.", "X ( k )=Σ n=0 N−1 x ( n )exp(− j 2 πnk/N ) (1) x ⁡ ( n ) = 1 N ⁢ ∑ k = 0 N - 1 ⁢ X ⁡ ( k ) ⁢ exp ⁡ ( j2π ⁢ ⁢ nk ⁢ / ⁢ N ) ( 2 ) Actually, the DFT and IDFT are realized using an FFT algorithm to perform high-speed operations while reducing the hardware calculations.", "A size N FFT of the FFT is equal to the total number N s of subcarriers.", "The FFT algorithm can be classified into a Decimation-In-Frequency (DIF) scheme and Decimation-In-Time (DIT) scheme.", "During the actual hardware design of the FFT, to reduce the hardware complexity, it is preferable to use a Pipeline FFT rather than realizing the FFT in a parallel way according to a Signal Flow Graph (SFG) of the FFT.", "The Pipeline FFT is chiefly used for an application field requiring high performance.", "This is because the Pipeline FFT, compared to the FFT realized according to the SFG, has lower hardware complexity, has a regular FFT architecture, has simpler control, and enables serial input and serial output.", "As shown in FIG. 1 , for OFDM symbol modulation, the general OFDM/OFDMA scheme reverse-copies the back 107 of a total of N FFT samples output from IFFT back to the forefront (or head) of IFFT output 103 , and attaches the copy to a guard interval 105 .", "The CP copied to the guard interval 105 uses N CP samples in the backmost portion of the OFDM symbol 101 .", "The general OFDM symbol modulator that uses the reverse copy scheme for CP insertion has the structure of FIG. 2 .", "In the DIF scheme-based IFFT 201 (hereinafter referred to as ‘DIF IFFT’) shown in FIG. 2 , while the input bits are ordered, the output bits are bit-reversed ordered.", "On the contrary, in the DIT scheme-based IFFT (hereinafter referred to as ‘DIT IFFT’), while the input bits are bit-reversed ordered, the output bits are ordered.", "This is because of the butterfly structure of the IFFT.", "For example, when the total number of N FFT samples of the IFFT is 8, DIF SFG is as shown in FIG. 3 and DIT SFG is as shown in FIG. 4 .", "In FIGS. 3 and 4 , reference numerals 301 and 401 indicate inputs of DIF IFFT and DIT IFFT, respectively, and reference numerals 303 and 403 indicate outputs of DIF IFFT and DIT IFFT, respectively.", "It can be appreciated that for DIF IFFT, the output bits are bit-reversed ordered as shown in FIG. 3 , and for DIT IFFT, the input bits are bit-reversed ordered as shown in FIG. 4 .", "Therefore, the OFDM symbol modulator needs a bit-reversed ordering unit 203 for reordering the bit data bit-reversed ordered at one of input/output ends of IFFT as shown in FIG. 2 .", "The ‘bit-reversed ordering’ refers to an operation in which when a number n is expressed in binary format, bits of the binary number are ordered in a reverse order as shown in Table 1.", "For example, for input bits ‘001’, their bit-reversed ordered output bits are ‘100’.", "TABLE 1 Bit reversed order Bit reversed order Order (decimal) Order (binary) (binary) (decimal) 0 000 000 0 1 001 100 4 2 010 010 2 3 011 110 6 4 100 001 1 5 101 101 5 6 110 011 3 7 111 111 7 Turning back to the description of FIG. 2 , because the inputs of DIF IFFT are allowed to be sequentially input to DIF IFFT but the outputs are output from DIF IFFT after undergoing bit-reversed ordering, there is a need for an IFFT output memory for bit reordering, and the output memory is prepared in the bit-reversed ordering unit 203 .", "Similarly, because the inputs of DIT IFFT are input to DIT IFFT after undergoing bit-reversed ordering, there is a need for an IFFT input memory for bit-reversed ordering.", "To this end, a bit-reversed ordering unit (not shown) serving as the input memory is prepared in the front stage of the DIT IFFT.", "A CP inserter 205 of FIG. 2 , because it should reverse-copy N CP samples at the back of an IFFT output, needs at least two buffers (memories) having an OFDM symbol size.", "In the conventional scheme, to complete one OFDM symbol, a delay occurs until N CP samples are output at the back of an IFFT output, and a total of N FFT samples of the IFFT output are stored in a first symbol buffer 205 c in the CP inserter 205 .", "In terms of the delay, because for reverse copy, the CP inserter 205 cannot output data to the next block until the data of N FFT samples are input to the buffer, the time delay corresponding to the N FFT samples occurs.", "Because the CP insertion process occurs every symbol interval, data input from the IFFT 201 and data output to a filter (not shown), or the next stage, should be simultaneously performed in the CP inserter 205 .", "Therefore, the OFDM symbol modulator 200 of FIG. 2 needs at least two buffers having the size of the IFFT 201 , such as the first symbol buffer 205 c for receiving the data output from the IFFT 201 and a second symbol buffer 205 d for outputting the data to the filter, and first and second switches 205 a and 205 b each switch inputs and outputs to/from the first and second symbol buffers 205 c and 205 d .", "That is, in the input/output scheme applied in FIG. 2 , while the first symbol buffer 205 c is filled up, data of the second symbol buffer 205 d is output and switched by the first and second symbol buffers 205 c and 205 d in the next symbol interval.", "As described above, the output end of DIF IFFT needs an operation of bit-reordering the output bit stream, and the input end of DIT IFFT needs an operation of bit-reordering the input bit stream.", "The two methods both need a buffer for bit reordering, and in terms of the delay, the OFDM symbol modulator cannot output the data to the next block until the data of N FFT IFFT samples is received, causing the time delay corresponding to the N FFT sample.", "As to the reason why the required buffer capacity and the delay happens, when the conventional CP insertion scheme is used, the samples corresponding to the CP are output at the back of an N FFT -symbol stream in terms of time.", "Therefore, in order to add the CP, it is necessary to buffer the entire IFFT output stream, and further, it is necessary to copy samples corresponding to the CP in the entire IFFT output stream and reverse-add the copied samples.", "In addition, the bit-reversed ordering process is needed for the inputting/outputting of the IFFT, causing the time delay.", "Therefore, proposed herein is a new scheme for allowing the value corresponding to the CP to be output beginning from the front of a total of N FFT samples during the output of the IFFT, thereby reducing the delay occurring during CP insertion and the required buffer capacity.", "If the bit-reversed ordering performed during the inputting/outputting of the IFFT is performed in parallel, the delay occurring during CP insertion and the required buffer capacity can be further reduced, and the hardware complexity can also be reduced.", "With reference to FIGS. 5 to 13 , a detailed description will now be made of embodiments of the present invention.", "The embodiments of the present invention will be described in light of 3 viewpoints.", "After the basic concept of the present invention is first described with reference to FIG. 5 , a first embodiment for forward-copying a CP for an output of the DIT IFFT to thereby reduce the required buffer capacity and the delay occurring during CP insertion will be described with reference to FIGS. 6 to 8 .", "Thereafter, a second embodiment for parallel-performing not only the forward CP copying but also the bit-reversed ordering required at the input/output ends of the DIT IFFT to thereby further reduce the delay occurring during CP insertion and the required buffer capacity will be described with reference to FIGS. 9 to 11 , and a third embodiment for performing forward CP copying on the output of the DIF IFFT to thereby reduce the required buffer capacity and the delay occurring during CP insertion will be described with reference to FIGS. 12 and 13 .", "FIG. 5 illustrates the concept of forward CP copying according to an embodiment of the present invention.", "IFFT, a realization algorithm designed to quickly perform the IDFT calculation fast, follows all the basic characteristics of the IDFT.", "For example, the intact circular shift characteristic and periodicity of the IDFT can be applied even in the IFFT.", "The circular shift characteristic and periodicity of the IDFT are as follows.", "Equation (3) indicates the circular shift characteristic of the IDFT, and Equation (4) indicates the periodicity of the IDFT.", "X[k]=X[k+N] (3) where N denotes the number of points of the IDFT.", "y[n]=x [( n−m )mod N ] Y[k]=W N −mk X[k],m εZ, 0 ≦n≦N (4) where W N n denotes a Twiddling factor for the DFT calculation, and W N n =exp(j2πn/N).", "If the characteristics of Equation (3) and Equation (4) are applied to the IFFT-based OFDM modulation process, the result of Equation (5) can be derived.", "If ⁢ ⁢ F - 1 ⁡ ( X ⁡ [ k ] ) = x ⁡ [ n ] , then ⁢ ⁢ F - 1 ⁡ ( W N FFT - kN CP * X ⁡ [ k ] ) = ⁢ F - 1 ⁡ ( exp ⁡ ( j2π ⁢ ⁢ N CP / N FFT ) * X ⁡ [ k ] ) = ⁢ x ⁡ [ ( n - N CP ) ⁢ ⁢ mod ⁢ ⁢ N FFT ] = ⁢ x ⁡ [ ( n - N CP + N FFT ) ⁢ ⁢ mod ⁢ ⁢ N FFT ] ( 5 ) where F 1 denotes the IFFT calculation, and k and n denote index values of an input stream and an output stream of the IFFT, respectively, and have an integer value between 0 to N FFT −1.", "Further, N CP denotes a length of a CP sample, and N FFT denotes an FFT size and is equal to the number of subcarriers.", "When the IFFT is performed by multiplying the input stream of the IFFT by a Twiddling factor corresponding to the length of a CP sample, the output of the IFFT undergoes circular rotation (or circular shift).", "In addition, when a value N CP is applied to the circular shift as shown in Equation (5), it is possible to obtain the result that the part corresponding to the CP value is first output from the IFFT and the remaining values are output following the corresponding part.", "As a result, when compared to the conventional scheme, the CP that should be copied last is first output by circular shift.", "Therefore, with the use of Equation (5), it is possible to forward-copy the CP part from the front of an IFFT output as shown in FIG. 5 .", "In FIG. 5 , an output 503 of the IFFT is assumed to be circular-shifted by a sample length N CP of a CP interval using the Twiddling factor.", "Under this assumption, the present invention first buffers the front of an OFDM symbol 501 where data of a CP interval 507 in the entire output 503 of the IFFT is located.", "Thereafter, if the output 503 of the IFFT is completed, the invention forward-copies the buffered data of the CP interval 507 and attaches it to the back 505 of the OFDM symbol.", "By circular-rotating the IFFT output by the CP interval using the Twiddling factor and then forward-copying the result as described above, the new scheme can insert a CP into an OFDM symbol without buffering all samples of the IFFT output like that of the conventional scheme described in FIG. 1 , thereby contributing to a reduction in the buffer capacity (or buffer size) required for the OFDM symbol modulator.", "In addition, the new scheme can perform CP insertion without waiting until all samples of IFFT are buffered like that of the conventional scheme, thereby contributing to a reduction in the delay occurring during CP insertion.", "A detailed description will now be made of the first embodiment to the third embodiment of the present invention, all of which use the forward CP copying.", "First Embodiment FIG. 6 illustrates a structure of a transmission apparatus in an OFDM system according to the first embodiment of the present invention.", "A transmission apparatus 600 of FIG. 6 includes an encoder 601 , a mapper 603 , a subcarrier allocator 605 , a scrambling code generator 607 , a multiplier 609 , an OFDM symbol modulator 611 , a filter 613 , a Digital-to-Analog Converter (DAC) 615 , a Radio Frequency (RF) processor 617 , and an antenna 619 .", "Among the elements of FIG. 6 , the remaining elements except for the OFDM symbol modulator 611 are equal to the corresponding elements of the general OFDM transmitter for encoding bit data, performing symbol mapping thereon, allocating subcarriers to the mapped data, spreading scrambling codes by multiplying, filtering an OFDM symbol, and transmitting it with a radio signal, so a detailed description thereof will be omitted herein.", "The OFDM symbol modulator 611 not only performs IFFT on the input data but also performs forward CP copying thereon according to the present invention in the CP insertion process.", "FIG. 7 illustrates a structure of an OFDM symbol modulation apparatus according to the first embodiment of the present invention.", "The apparatus shown in FIG. 7 indicates the OFDM symbol modulator 611 of FIG. 6 .", "The apparatus of FIG. 7 is an embodiment using DIT IFFT 707 , which performs forward CP copying in such a manner that input bits of the IFFT undergo bit-reversed ordering.", "In FIG. 7 , a Twiddling factor generator 701 sequentially outputs Twiddling factors that should be multiplied by data X[k] in the frequency domain by a multiplier 703 .", "According to the characteristics of the Twiddling factors, the number of Twiddling factors that should be generated depending on the value k of the input data X[k] is limited to, for example, N FFT /N CP where N FFT denotes the total number (or length) of samples of an IFFT output, and N CP denotes the number (or length) of samples of a CP interval.", "If indexes of the limited number of Twiddling factors are defined as a ‘Twiddling factor number’, the Twiddling factor multiplied by the input bits according to the Twiddling factor number is expressed as Equation (6).", "Twiddling factor (Twiddling factor number)=exp(− j 2π*Twiddling factor number* N CP /N FFT ) (6) In addition, the Twiddling factor number according to the index k of the input data X[k] has a relationship of Equation (7).", "Twiddling factor number( k )=( k mod( N FFT /N CP )), k= 0,1,2 , .", "N FFT −1 (7) For example, if a CP length is assumed to be ⅛ of the FFT size like in the WiMAX standard, the number of Twiddling factor numbers is limited to 8, and the Twiddling factors that should be multiplied according to the 8 Twiddling factor numbers are as shown in Table 2.", "TABLE 2 Index Twiddling factor number Twiddling factor If(k mod 8) = 0 0 1 If(k mod 8) = 1 1 1 2 ⁢ ( - 1 - i ) If(k mod 8) = 2 2 −i If(k mod 8) = 3 3 1 2 ⁢ ( 1 - i ) If(k mod 8) = 4 4 −1 If(k mod 8) = 5 5 1 2 ⁢ ( - 1 + i ) If(k mod 8) = 6 6 i If(k mod 8) = 7 7 1 2 ⁢ ( 1 + i ) The Twiddling factor multiplied by an input stream to IFFT 707 in the multiplier 703 of FIG. 7 is set such that an output of IFFT 707 is circular-shifted by a length of a CP sample.", "A bit-reversed ordering unit 705 bit-reversed orders an IFFT input multiplied by the Twiddling factor, and the IFFT 707 performs IFFT according to the DIT scheme.", "Here, an IFFT output, compared to the general IFFT output, is the data circular-shifted by a sample length N CP of the CP interval.", "A CP inserter 709 of FIG. 7 includes first and second switches 709 a and 709 b , and a CP buffer 709 c .", "The first switch 709 a performs switching so as to store the data of only the CP interval in the CP buffer 709 c at the front of an IFFT output stream while outputting an IFFT output to the second switch 709 b .", "The second switch 709 b performs switching so as to output the IFFT output delivered from the first switch 709 a to a filter (indicated by reference numeral 613 of FIG. 6 ), or the next stage, and after the output of IFFT 707 is completed in the corresponding block, outputs the data stored in the CP buffer 709 c to the filter 613 following the corresponding output.", "The switching and buffering operation of the CP inserter 709 can be performed by an undepicted controller.", "FIG. 8 illustrates an OFDM symbol modulation method according to the first embodiment of the present invention.", "The method of FIG. 8 will be described with reference to FIG. 7 .", "In step 801 , a Twiddling factor generator 701 generates a Twiddling factor for forward CP copying, and multiplies the generated Twiddling factor by a transmission signal being input to an IFFT 707 by means of a multiplier 703 .", "In step 803 , a bit-reversed ordering unit 705 bit-reverse orders the transmission signal multiplied by the Twiddling factor, and outputs the resulting transmission signal to the IFFT 707 .", "In step 805 , the IFFT 707 performs the DIT IFFT on the bit-reversed ordered transmission signal, and outputs the IFFT data circular—shifted by a CP length.", "A CP inserter 709 buffers a CP part at the front of the IFFT output in step 807 , and attaches the buffered CP part to the back of the IFFT output in step 809 .", "According to the first embodiment, the new scheme can insert a CP into an OFDM symbol without the need for buffering all of the samples of the IFFT output like that of the conventional scheme, and can also perform CP insertion without waiting until all samples of the IFFT are buffered.", "When the DIT IFFT is used as described in the first embodiment, it is possible to parallel-perform the bit-reversed ordering and circular shift required in the IFFT input at the front stage of IFFT.", "In this case, the IFFT output can be used.", "Next, the second embodiment will propose a scheme of performing bit-reversed ordering and circular shift for an IFFT input at the front stage of IFFT.", "Second Embodiment FIG. 9 illustrates a structure of a transmission apparatus in an OFDM system according to the second embodiment of the present invention.", "A transmission apparatus 900 of FIG. 9 includes an encoder 901 , a mapper 903 , a subcarrier allocator 905 , a scrambling code generator 907 , a Twiddling factor generator 909 , a multiplier 910 , an OFDM symbol modulator 911 , a filter 913 , a DAC 915 , an RF processor 917 , and an antenna 919 .", "In the transmission apparatus of FIG. 9 , its basic operation of encoding bit data, performing symbol mapping thereon, allocating subcarriers to the mapped data, spreading scrambling codes by multiplying, filtering an OFDM symbol, and transmitting it with a radio signal is equal to the operation of the general OFDM transmitter, so a detailed description thereof will be omitted herein.", "However, according to the present invention, the transmission apparatus of FIG. 9 includes, at the front stage of the OFDM symbol modulator 911 , the Twiddling factor generator 909 for generating Twiddling factors for circular shift, and further includes bit-reversed ordering units 905 a , 907 a and 909 a for bit-reversed ordering outputs of the subcarrier allocator 905 , the scrambling code generator 907 and the Twiddling factor generator 909 , respectively.", "Among the bit-reversed ordering units 905 a , 907 a and 909 a , the bit-reversed ordering unit 907 a included in the scrambling code generator 907 and the bit-reversed ordering unit 909 a included in the Twiddling factor generator 909 may not be needed in the actual configuration, because the scrambling code generator 907 can be designed such that it generates scrambling codes to be multiplied by the bit-reversed ordered transmission signal during the generation of the scrambling codes.", "Similarly, the Twiddling factor generator 909 can also be configured such that it generates Twiddling factors to be multiplied by the bit-reversed ordered transmission signal during the generation of the Twiddling factors.", "The OFDM symbol modulator 911 performs the IFFT on the input data and also performs the forward CP copying on the input data in the CP insertion process according to the present invention.", "By parallel-performing forward CP copying and bit-reversed ordering on the transmission signal being input to the IFFT at the front stage of the OFDM symbol modulator 911 according to the second embodiment of FIG. 2 , the new scheme can further reduce the buffer capacity required in the OFDM symbol modulator 911 and the delay occurring during CP insertion.", "In the general OFDM transmitter, because the element such as the subcarrier allocator 905 already has an internal buffer for performing its corresponding operation, the inclusion of the bit-reversed ordering unit 905 a in FIG. 9 may not need a separate memory for bit-reversed ordering of the transmission signal, because the OFDM transmitter only needs to simply bit-reverse order an allocation address for the input data during subcarrier allocation.", "To this end, for subcarrier allocation, the subcarrier allocator 905 of FIG. 9 can use the allocation scheme in which bit-reversed ordering for input data has already been reflected.", "Equation (8) defines an allocation algorithm where the bit-reversed ordering for input data has already been reflected in the subcarrier allocator 905 of FIG. 9 .", "Allocated data ( k ′)=bit reversed (Allocated data ( k )), k =0,1,2 , .", ",N FFT −1 where k ′=bit reversed( k ), k′= 0,1,2, .", "N FFT −1 (8) Similarly, the multiplier 910 where the Twiddling factors are multiplied can be designed using the existing multiplier (indicated by reference numeral 609 of FIG. 6 ) where the scrambling codes are multiplied.", "In the second embodiment of FIG. 9 , because the data bit-reversed ordered by the subcarrier allocator 905 is output, the scrambling code generator 907 and the Twiddling factor generator 909 also output the scrambling codes and the Twiddling factors, respectively, in which the bit-reversed ordering has already been reflected according to the following method.", "The bit-reversed ordering method for the Twiddling factor will first be described.", "While the Twiddling factor number based on the index k of the Twiddling factor can be expressed as Equation (7) in the first embodiment, the Twiddling factor number of the bit-reversed ordering-reflected Twiddling factor can be expressed as Equation (9) for the index k′ of the bit-reversed ordered input data.", "Twiddling factor number( k ′)=bit reversed(round( k′/N CP )) where k ′=bit reversed( k ), k′= 0,1,2, .", ", N FFT −1 (9) where ‘round’ refers to a rounding operator.", "The Twiddling factor determined according to the Twiddling factor number in Equation (9) is equal to that determined before the bit-reversed ordering is applied, and is determined as shown in Equation (6).", "For example, if a ratio of N FFT to N CP is 8:1 like in the WiMAX standard, the Twiddling factors generated by the Twiddling factor generator 909 of FIG. 9 according to the index k′ of the bit-reversed ordered input data are as shown in Table 3.", "TABLE 3 k′ (bit reversed reordering index) Twiddling factor number Twiddling factor 0~N CP − 1 0 1 N CP ~2 * N CP − 1 4 −1 2 * N CP ~3 * N CP − 1 2 −i 3 * N CP ~4 * N CP − 1 6 i 4 * N CP ~5 * N CP − 1 1 1 2 ⁢ ( - 1 - i ) 5 * N CP ~6 * N CP − 1 5 1 2 ⁢ ( - 1 + i ) 6 * N CP ~7 * N CP − 1 3 1 2 ⁢ ( 1 - i ) 7 * N CP ~8 * N CP − 1 7 1 2 ⁢ ( 1 + i ) The scrambling codes generated by the scrambling code generator 907 of FIG. 9 are also bit-reversed ordered and then multiplied by the bit-reversed ordered input data, and a description of the bit-reversed ordering method will be described below.", "The bit-reversed ordering method can previously generate scrambling codes according to the index k′ of the bit-reversed ordered data using the corresponding scrambling seed, and store the generated scrambling codes in the memory for later use.", "That is, the bit-reversed ordering units 905 a , 907 a and 909 a of FIG. 9 can be realized by means of the memories used by the subcarrier allocator 905 , the scrambling code generator 907 and the Twiddling factor generator 909 , respectively.", "As to the memory used by the scrambling code generator 907 , it can be understood that because the scrambling code is 1-bit data, its required memory capacity is very low.", "The scrambling codes are output in order of bit-reversed ordering made according to Equation (10).", "Scrambling code( k ′)=bit reversed(scrambling code(scrambling seed, k )), k= 0,1,2 , .", "N FFT −1 where k ′=bit reversed( k ), k′= 0,1,2 , .", ",N FFT −1 (10) FIG. 10 illustrates a structure of an OFDM symbol modulation apparatus according to the second embodiment of the present invention.", "The apparatus shown in FIG. 10 indicates the OFDM symbol modulator 911 of FIG. 9 .", "In the OFDM symbol modulation apparatus 1000 of FIG. 10 , the input data is received after it underwent bit-reversed ordering in a parallel way at its front stage as described above.", "IFFT 1001 performs IFFT on the bit-reversed ordered input data according to the DIT scheme.", "The IFFT output, compared to the general IFFT output, is the data circular-shifted by a sample length N CP of a CP interval.", "A CP inserter 1003 of FIG. 10 includes first and second switches 1003 a and 1003 b , and a CP buffer 1003 c , and its operation is equal to that of the CP inserter 709 of FIG. 7 , so a detailed description thereof will be omitted.", "FIG. 11 illustrates an OFDM symbol modulation method according to the second embodiment of the present invention.", "The method of FIG. 11 will be described with reference to FIG. 10 .", "In step 1101 , a front stage of IFFT 1001 multiplies the bit-reversed ordered input transmission signal by a Twiddling factor for forward CP copying.", "Thereafter, in step 1103 , the IFFT 1001 performs the DIT IFFT on the bit-reversed ordered transmission signal, and outputs the IFFT data circular-shifted by a CP length.", "A CP inserter 1003 buffers a CP part at the front of the IFFT output in step 1105 , and attaches the buffered CP part to the back of the IFFT output in step 1107 .", "According to the second embodiment, the new scheme can insert a CP into an OFDM symbol without the need of buffering all of the samples of the IFFT output like that of the conventional scheme, and can also perform CP insertion without waiting until all of the samples of the IFFT are buffered.", "In addition, the new scheme can perform bit-reversed ordering and circular shift on the IFFT input at the front stage of the IFFT, contributing to a further reduction in the required buffer capacity and the delay.", "Although the foregoing description of the first embodiment and the second embodiment is directed to the case where the present invention is applied to the DIT IFFT, the third embodiment will propose a scheme of performing forward CP copying for the DIF IFFT, thereby contributing to a reduction in the required buffer capacity and the delay during CP insertion.", "Third Embodiment In the third embodiment, the OFDM transmission apparatus can use the intact structure of FIG. 9 described in the first embodiment, after simply modifying only the structure of the OFDM symbol modulator as shown in FIG. 12 .", "FIG. 12 illustrates a structure of an OFDM symbol modulation apparatus according to the third embodiment of the present invention.", "In the OFDM symbol modulation apparatus 1200 of FIG. 12 , a Twiddling factor generator 1201 sequentially outputs Twiddling factors that should be multiplied by the frequency-domain data by means of a multiplier 1203 .", "Here, the Twiddling factors are generated in the manner described in the first embodiment.", "The Twiddling factor multiplied by the input stream of IFFT 1205 is set such that the output of IFFT 1205 is circular-shifted by a length of a CP sample.", "However, while the first embodiment bit-reversed orders an input of the IFFT using the DIT IFFT, the third embodiment uses the DIF IFFT for the bit-reversed ordering, so the input of the IFFT is directly input to the IFFT 1205 without undergoing the bit-reversed ordering process.", "In FIG. 12 , the IFFT 1205 performs the IFFT according to the DIF scheme.", "Here, the IFFT output, compared to the general IFFT output, is the data circular-shifted by a sample length N CP of a CP interval.", "A bit-reversed ordering unit 1207 bit-reversed orders the circular-shifted IFFT output.", "A CP inserter 1209 of FIG. 12 includes first and second switches 1209 a and 1209 b , and a CP buffer 1209 c , and its operation is equal to that of the CP inserter 709 of FIG. 7 , so a detailed description thereof will be omitted.", "FIG. 13 illustrates an OFDM symbol modulation method according to the third embodiment of the present invention.", "The method of FIG. 13 will be described with reference to FIG. 12 .", "In step 1301 , a Twiddling factor generator 1201 generates a Twiddling factor for forward CP copying, and multiplies the generated Twiddling factor by a transmission signal being input to IFFT 1205 by means of a multiplier 1203 .", "In step 1303 , the IFFT 1205 performs the DIF IFFT, and outputs the IFFT data circular-shifted by a CP length.", "In step 1305 , a bit-reversed ordering unit 1207 bit-reversed orders the circular-shifted IFFT output, and outputs the result to a CP inserter 1209 .", "As for the DIF IFFT, its output undergoes bit-reversed ordering before being output.", "Therefore, if the bit-reversed ordering unit 1207 performs bit-reversed ordering in step 1305 , the IFFT output is reordered in its original bit order.", "Thereafter, the CP inserter 1209 buffers a CP part at the front of an IFFT output in step 1307 , and attaches the buffered CP part to the back of the IFFT output in step 1309 .", "According to the first embodiment to the third embodiment of the present invention, because the value corresponding to a CP in an IFFT output is output from the beginning, the new scheme can immediately forward the value output from the IFFT to the next stage without the need to store all of the samples of an OFDM symbol in the buffer.", "Therefore, the new scheme, compared to the conventional OFDM symbol modulation scheme, can reduce the delay by an N FFT -sample length.", "In addition, the conventional scheme, as it should store the entire OFDM symbol, uses at least two N FFT -size buffers for the CP inserter, whereas the new OFDM symbol modulation scheme proposed by the present invention can reduce the required buffer capacity because the CP inserter uses only one CP-size buffer as the new scheme needs only to store in the CP buffer the value corresponding to the first CP interval in the IFFT output.", "For example, assuming that 1024-point FFT and a 128-sample CP are used and the number of IFFT input/output bits is 16 for each of the I and Q channels, the buffer reduction ratio required for the OFDM symbol modulator is as follows: Conventional IFFT Output Buffer Decrement=1024 samples*32 bits*2=65536 bits CP Buffer Increment=128 samples*32 bits*1=4096 bits Scrambler Buffer Increment=1024 samples*1 bit*1=1024 bits Buffer (Memory) Decrement Ratio=(4096+1024−65536)/65536=92% Decrement As a result, the proposed scheme, compared to the conventional scheme, can reduce about 92% of the required buffer capacity.", "As is apparent from the foregoing description, the present invention can reduce the delay and the required buffer capacity occurring in the OFDM transmitter that performs CP insertion in the OFDM symbol modulation process, thereby contributing to improvement of the performance of the OFDM transmitter.", "In addition, the present invention can reduce the data transmission preparation time at the OFDM transmitter, thus contributing to an increase in the timing margin and a decrease in the hardware complexity of the transmitter.", "While the invention has been shown and described with reference to a certain preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims." ]
This application is a continuation of U.S. patent application Ser. No. 430,080 filed Nov. 1, 1989 entitled LIGHT CONTROL WITH COLOR ENHANCEMENT now U.S. Pat. No. 5,054,902 which was a continuation of Ser. No. 921,312 (now abandoned) filed Oct. 21, 1986 as a continuation of Ser. No. 223,840 (now abandoned) filed Jan. 9, 1981 which was a continuation of Ser. No. 645,262 (now abandoned) filed Dec. 29, 1975 each of these patent applications being titled LIGHT CONTROL WITH COLOR ENHANCEMENT. BACKGROUND OF THE INVENTION The invention relates to the enhancement of color by means of the optical interference effects which are produced by thin films. Interference phenomena in connection with thin films are well known. A summary of some of these phenomena is set forth in an article in the Scientific American entitled "Optical Interference Coatings", December 1970, pages 59-75. Although the article starts with a display of various colors in a colored illustration and includes references to certain color effects produced in nature by thin films such as oil slicks, soap films, oyster shells, and peacock feathers, the various scientific uses of optical interference coatings described in the article do not include the conscious production of visual color effects. A major use of optical coatings is the production of reflection or non-reflection across the visible spectrum. Thus anti-reflection coatings are used on lenses, and multiple reflective coatings are used in dielectric mirrors. Applications requiring enhancement at a particular wavelength have an analytical rather than a visual purpose and require the maximum reflectivity possible, such as the laser and the Fabry-Perot interferometer. Although the Plumbicon tube separates light into primary colors, these are not viewed, but produce signals for transmission to a receiver via megacycle carrier waves. Moreover, not only do these prior scientific uses of optical interference films have no visual purpose, but the way in which the films are used to achieve a particular effect is such that, once adjusted for this effect, the optical device in question can no longer be adjusted to control other parameters. Various methods have also been used to alter the spectral transmission and other characteristics (absorption, color etc.) of materials such as glasses or plastics in order to make them useful as sunglasses, either as light absorbers to reduce and/or control the amount and nature of light reaching the eye, or for cosmetic reasons. These methods have included coloring the basic materials, adding a colored layer over the surface, adding a neutral filter to one or more surfaces, adding a polarizing material, etc. However, the application of interference films to provide interference colors has not normally been used for such purposes. Such colors, although observed by many investigators, have not been used in general for cosmetic purposes because of difficulties in obtaining "predetermined" colors and because the colors lacked "depth", particularly on the transparent or partly absorbing substrates that are used for sunglasses and similar purposes. It is the purpose of this invention to show how such colors can be obtained having "depth" or color "density" under controlled conditions. In addition, this invention shows that such "high depth" colors can be obtained under conditions which allow the user to control the amount and nature of light transmitted to and through the substrate. This invention will also show how the latter control of the transmitted light can also be obtained while having "low depth" coloring. In fact, any practical degree and/or combination of color depth and transmitted light control can be obtained by proper use of the present invention. In conventional optical techniques, interference films are commonly used to fabricate band-pass light filters and to "increase" (as distinct from the invention's effect, which is always to decrease the transmitted light, as in the case of sunglasses and other light reducing devices) the amount of transmitted light (for lenses, binoculars, etc.) through their use as so-called quarter-wavelength anti-reflection filters, the latter being a simple form of the former. As discussed below, since any film of "optical" thickness λ/4 (λ being the wavelength of the radiation) is effective only around one value of λ (or specific functions thereof), the application of such films having λ values in the visible range causes the reflected and transmitted light components to be colored, even when the incident light is white, as is usually the case for sunglasses, windows etc. By choosing film thicknesses properly, one can get a wide spectrum of reflected colors (the color of the transmitted light being the spectrum of the incident light, normally white, minus the reflected and absorbed components). This technique has not normally been used as a "coloring" mechanism primarily because of difficulties in controlling the color and very importantly because of the lack of intensity or color depth when used on transparent or partly absorbing substrates. In fact, such colors are normally observed only as a necessary adjunct to other factors such as the need for an anti-reflection filter on binoculars. The lack of color depth (pastel shading in general) is acceptable for some purposes (e.g. lightly tinted sunglasses) but is not adequate for others. Another reason why interference techniques have not been put to widespread commercial use is the need to put such films on the outside of the lens (or window etc.) for best cosmetic effect or function. In practice, this means the films themselves must be quite hard or must be covered with another harder (normally transparent) film or layer to prevent scratching or other attack, thereby complicating the manufacturing process. The use of interference films has therefore been primarily restricted to optical instruments (binoculars, spectrometers, etc.) and techniques (band pass filters, etc.) where such factors are relatively unimportant because of the care which the optical components receive and/or the undesirability of or lack of need for coloration. In fact, in many scientific instruments which use interference effects for measurement purposes, monochromatic light must be used at some stage to provide the necessary operation. For most such purposes, conventional interference techniques are adequate. However, in the case of plastic eyeglass lenses (both prescription and sunglass) there is a need for a coloring technique which can provide vivid cosmetic colors and also give protection to the soft plastic surface while providing the light reflection and/or absorption necessary to perform a worthwhile sunglass function. Similar applications exist in plastic windows, plastic decorator panels or building materials, etc. and also for other substrate materials (e.g. glass) in special applications (decorator panels or functional windows, etc.) Other applications will be obvious to those skilled in the art who become familiar with this invention. Some of such applications may simply require a color effect without the need to adjust other parameters such as light transmission. For example, such applications as plastic wall panels protected against scratching, costume jewelry, decorative dishes, bottles, and the like may incorporate the principles of the invention simply for a coloring effect. In these applications, the interference coloring film must usually be extremely well bonded, to a degree not normally achieved with standard deposition techniques. Although any "appropriate" process capable of attaching the required materials in the "required" form to the substrate surface may be used in applying this invention, the invention itself has been demonstrated using ion beam sputtering and ion beam implantation sputtering techniques. The former is disclosed, for example, in U.S. Pat. No. 3,472,751. The latter is disclosed in my Disclosure Document No. 032867, filed Jun. 5, 1974, and can be used to deposit very tightly bonded, durable films on plastics and other difficult substrates, the film of deposited material commonly, but not necessarily, being harder than the substrate material. SUMMARY OF THE INVENTION The invention deals with transparent solids such as windows, eyeglasses, etc., (and, in certain embodiments, coloring effects on solids whether transparent or not, such as wall panels, costume jewelry, etc.) and provides means for enhancing color of light incident upon the transparent solid while at the same time permitting further control of the radiation transmitted and reflected over a wide spectrum. The invention makes use of the discovery that the color of the reflected or the transmitted light may be enhanced in a way which does not materially affect the bulk of the visible light passing through or reflected by the transparent solid. In accordance with the invention color enhancement is achieved by interference between light reflected from a semi-reflecting layer on the transparent solid and light reflected from the outer surface of a dielectric layer which is hermetically sealed over the semi-reflecting layer. The reflectivity at each of these surfaces need not be particularly large since color enhancement is achieved by a differential effect whereby the eye detects either the prominence of constructive interference at a particular band of wavelengths over the background radiation, or the color effect produced when a band-width of light is removed from the reflective light by destructive interference. In each case the bulk of the radiation is not affected by the interference phenomena, so that the light transmitted through, reflected by, or absorbed in the transparent solid may still be controlled by varying the thickness of the semi-reflecting layer and by other means. BRIEF DESCRIPTION OF THE DRAWING The invention may best be understood from the following detailed description thereof, having reference to the accompanying drawings, in which FIG. 1 is a diagrammatic sectional view of a series of layers arranged in accordance with the invention; FIG. 2 is a view similar to that of FIG. 1 showing the transmission and reflection of light rays incident upon a glass layer in air; FIGS. 3(a)-3(c) are a series of graphs showing the effect of superimposition of waves; FIG. 4 is a view similar to that of FIG. 2 wherein the glass layer is supported upon a plastic substrate; FIGS. 5(a) and 5(b) are a series of views similar to that of FIG. 2 showing the reflection of light rays incident upon a highly reflecting layer; FIGS. 6(a) and 6(b) are a series of views similar to those of FIG. 5 showing the reflection of light rays incident upon a semireflecting layer in accordance with the invention; and FIG. 7 is a view similar to those of FIG. 6 wherein glass of a relatively high index of refraction is used. DESCRIPTION OF PREFERRED EMBODIMENTS The primary aspect of this invention is the means of obtaining on suitable substrates, optical layers which with reflected light, i.e. to the viewer on the side of the incident light, have a "colored" metallic appearance as opposed to the conventional neutral metallic appearance normally used in sunglasses, mirrors, etc. A second aspect is the means to obtain optical layers which control the characteristics of the visible light and/or other radiation reaching a viewer on the opposite side of the substrate from the incident visible light and/or other radiation (hereinafter collectively referred to as radiation), while simultaneously controlling the "color" of the composite structure as viewed by an observer on the side of the substrate upon which the radiation is originally incident. A third aspect is to "control" the transmitted radiation and colors as in the second aspect above while simultaneously controlling the amount and type of incident radiation which is absorbed in the original substrate, by controlling the amount of incident radiation which is reflected away from the substrate direction. A fourth aspect is to obtain the functions above while simultaneously protecting the underlying substrate and deposited material from mechanical and/or chemical attack. The physical arrangement required in accordance with the invention to obtain all of the above functions is shown in FIG. 1. The important feature of this arrangement is the combination of a partially-reflecting or so called semi-reflecting (reflectivity being less than a highly polished or deposited "opaque" metal layer and more than a low reflectivity substrate such as clear glass or plastic) layer 1 and a layer 2 of transparent or "partially" absorbing material (such as clear or colored glass, respectively) with index of refraction and thickness appropriate to obtain the desired features of the invention. How this combination differs from conventional interference methods and how it works in practice are described below. If necessary, a second layer 3 of transparent or partially absorbing material can be put over the interference layer 2 to provide additional protection and/or coloring effects in conjunction with those due to the interference layer. The semi-reflecting layer 1 is itself supported on a suitable underlying substrate 4. The operation of this invention and the differences with respect to previous methods can best be understood by comparison with classical optical theory and practices related to interference effects due to thin films. This can be done in stages as shown in FIGS. 2-6. The incident light may be incident at any angle θ from 0° to 90°. However, in the following discussion, unless stated otherwise the light is considered to be incident normal to the surface (i.e. θ=0°) to simplify and clarify the description of the invention. The light rays in FIGS. 2, 4, 5, and 6 are shown at an angle θ≠0° for purposes of ray identification and only the reflected rays of interest are shown. The corresponding transmitted rays are the incident rays minus the reflected component. If the substrate medium is absorbing (e.g. colored glass) the final transmitted ray would also be minus the absorbed component. Unless otherwise stated, all dielectric materials shown are non-absorbing and are assumed to have indices of refraction that are constant across the visible spectrum. The first element in defining the invention is a simple very thin (e.g. <10,000 Å thick) film 5 of glass suspended in an air medium as shown in FIG. 2. This is analogous to the classical soap film in which interference colors are observed corresponding to discrete film thicknesses t. In general, there is a phase change of ±π if a light wave travelling in a medium with a given index of refraction is reflected at the interface with a medium having a higher index of refraction and the phase change is 0 if the reflecting medium has a lower index of refraction than the original medium. This assumption is not rigorously true for many cases of reflection at the boundary of two different media, for example at many air-metal interfaces, but is adequate and convenient for purposes of explanation. It is valid for the air-glass-air case shown in FIG. 2. Exact phase changes of 0 or ±π are used below in discussing all of the interfaces in FIGS. 2, 4, 5 and 6 and where this can lead to appreciable difference in operation of the invention, it is discussed. In no event does the divergence from a rigorous treatment alter the basic concepts of the invention. Since there is a phase change of ±π at the first interface in FIG. 2 and 0 at the second, it can be shown that the first ray reflected from the air-glass interface is reinforced through constructive interference effects at wavelength λ c given by ##EQU1## where t≡thickness of glass n g ≡index of refraction of glass θ≡angle of incidence For θ=0, cos θ=1 and equation (1) becomes ##EQU2## (All subsequent formulae and discussions assume θ=0) Reflectivity at the interface between two non-absorbing media is given by the formula ##EQU3## where n o ≡index of refraction of first medium; in this case, air. n g ≡index of refraction of second medium; in this case, glass. For n o =1(air) and n g =1.46(fused silica) R=3.5% Unless otherwise noted it is assumed for purposes of discussion that the reflectivity is the same at all λ's of interest, i.e. n g is constant across the spectrum of interest. From FIG. 2 it is seen that the component (R 1 ) reflected from the first air-glass interface has an intensity of 3.5% of the original ray. The remaining 96.5% of the original ray is reflected from the rear glass-air interface with an intensity relative to the original ray of 96.5%×3.5%=3.38%. At the front surface this internal ray is again reflected (reflectivity=3.5%) with an intensity relative to the original ray of 3.38%×3.5%=0.118% and the remaining 3.38%×96.5%=3.26% emerges as the second component (R 2 ). The part of the first internal ray (0.118% of original intensity) which is rereflected at the front surface, will be rereflected from the back surface with an intensity of 0.118%×3.5%=0.00413% and will emerge through the front surface as R 3 having an intensity of 0.00413%×96.5%=0.0040% after an addition 3.5% loss through reflection at the front surface. The internal reflections continue with corresponding decreases in the intensity of the rays R 4 , R 5 . . . emerging through the front surface. If the first internally reflected ray R 2 is in phase with the originally reflected ray R 1 upon emerging as given by equation (3), the second internally reflected ray (R 3 after emerging) is out of phase since the total additional path length is a 1/2 integral number of wavelengths long and there is no additional phase change at either the front or rear internal reflections. The third internally reflected ray (R 4 after emerging) is in phase etc. R 1 and R 2 are in phase and of much larger magnitude than the other rays, resulting in an enhancement of the color at the particular wavelength involved (assuming glass thickness t corresponding to constructive interference at visible wavelengths λ c ). A rough approximation is a doubling of the energy reflected at λ c as given by equation (3) and shown (for the first two rays R 1 and R 2 ) in FIG 3(a). At other wavelengths near the coherent wavelength, the amplitudes can be partially reinforced as in FIG. 3(b) where it is assumed that R 2 is roughly 36° out of phase with R 1 . If, however, R 1 and R 2 are π or near π out of phase as in FIG. 3(c), there can be almost complete annihilation of the reflected components at that wavelength. The wavelengths λ D for maximum out of phase destructive interference is given by: ##EQU4## Whether major constructive and destructive interference effects can occur simultaneously in the same film and to what extent is primarily a function of the film thickness and is discussed below. The net result with respect to the film is an apparent color corresponding to wavelengths around λ c (if constructive interference dominates) or at that color that remains after that corresponding to wavelengths around λ D are removed (if destructive interference dominates). These colors for this type of film can be reasonably intense if the film is not exposed to a lot of white light incident on the rear surface. Since the transmitted light is the complement of the reflected light, if there were white light incident on the rear surface of intensity level 100% of that incident on the front surface, the two wave trains would tend to complement each other and produce white light as viewed from either side. However, if most of the light is incident on the front surface, the "differential" effect on the reflected light can be quite significant leading to relatively intense coloring. For example, if only constructive interference occurs, those wavelengths near λ C will have an intensity level of R 1 +R 2 -R 3 +R 4 etc.≡I c ≈R 1 +R 2 =3.5+3.26=6.76% while those at wavelengths far removed from λ c , where R 2 is half in phase and half out of phase with R 1 will have an intensity I B roughly equal to that of R 1 , i.e. approximately 3.5%. A convenient measure of the differential level of the constructive color component above background is the difference between the enhanced intensity I c and the random background intensity I B , divided by the random background intensity I B . For the case under consideration this is approximately ##EQU5## if only the reflected components are considered. In practice, some white light is incident on the rear surface and the differential effect is much less than this. It should be noted that the structure shown in FIG. 2, although producing vivid coloring, is not adequate for most practical purposes because of the thinness of the glass layer involved. It should also be noted that the coloring effects are due to the ability of the eye to observe and evaluate the "relative" amplitudes of the various components of the light entering the eye, so that the greater the differential height of the coherent λ C (for example above) "above background", the deeper or more vivid will be the apparent color. Although the above discussion consists primarily of an analysis of observed facts and in that sense is trivial, it is important to a clear understanding of the present invention as discussed below. FIG. 4 gives the next stage in understanding the invention and shows a glass film 5 of index of refraction n g intimately attached by some method to a plastic substrate material 6 having index of refraction n p where n p ≳n g and both media are non-absorbing. (The materials chosen here and in subsequent stages of the development are arbitrary and could be replaced with other "suitable" materials without altering the basic explanation.) In this case there is a phase change of ±π upon reflection at the front surface and "another" phase change of ±π upon reflection at the glass-plastic interface. The condition for constructive interference of the first internally reflected ray R 2 with the initial reflected ray R 1 , in this case is given by; ##EQU6## The condition for destructive interference is given by; ##EQU7## However, in this case the amount of light reflected from the glass-plastic interface, as given by equation (3) for n g =1.46 and n p =1.54(plastic) is only 0.071%×96.5%=0.0686% of the incident light with the emerging component R 2 only 0.0686%×96.5%=0.0662%. The plastic substrate 6 is assumed to be very thick since it must provide support, and so there are no interference effects due to reflection at the rear plastic-air interface. This additional light of R 2 , even if satisfying equation (5), will therefore produce a differential effect of only 0.066/3.5=0.019 or 1.9% above background. Such combinations of materials therefore have only a very slightly observable coloring. In such a case white light penetrating from the back surface also tends strongly to wash out any net coloration since almost all of the white light incident on the back surface will emerge from the front as white light, raising the background level to approximately 100%. It should be noted that in this case, if R 1 and R 2 are in phase, R 3 will be out of phase; i.e. will destructively interfere with R 1 and R 2 because of the additional ±π phase change at the second reflection at the glass-plastic interface. The additional path length in the glass is, of course, an integral number of wavelengths since that is the condition for the first internally reflected ray R 2 to be in phase with R 1 . The third internally reflected ray R 4 is in phase, and the fourth R 5 out of phase etc. This factor is unimportant for the case shown in FIG. 4 because of the small reflectivities and intensities involved, but is important in the new elements involved in the present invention. Next consider a simple highly polished opaque reflecting metal layer 7 as in FIG. 5(a) (e.g. vacuum deposited Al on glass) with a reflectivity assumed for discussion to be 90% (normally higher) and flat across the visible spectrum. The reflectivity for such an opaque absorbing medium with light incident from a dielectric of index of refraction n o is given by: ##EQU8## where n m ≡index of refraction of metal k m ≡extinction coefficient for metal which reduces to ##EQU9## For some metals such as Al where the relative values of n m and k m are appropriate across the spectrum (visible) the reflectivity remains fairly flat and the reflected light has a neutral gray pure metallic appearance. For other metals such as Cu, the relative values of n m and k m are such that R varies across the visible spectrum (e.g. for evaporated Cu, R≈58% at 4,500 Å and R≈96% at 7,000 Å). For the example given, the Cu therefore appears by reflected light to be reddish since more of the red end of the spectrum is reflected. As discussed later, this factor is also used in controlling coloration using the present invention. Returning to FIG. 5(a) the situation is quite simple with only those rays reflected from the first surface being viewed by the observer (i.e. a simple front surface mirror). If, however, the metal is covered by a thin layer (such as that shown at 8 in FIG. 5(b)) of glass, or other appropriate medium, the situation changes to that shown in FIG. 5(b) where again the "initial" reflected ray is only 3.5% of the incident energy. A phase change of ±π is assumed at the glass-metal interface. In a more rigorous treatment the phase change ρ is given by: ##EQU10## where the symbols have the meanings previously given. For many glass-metal combinations ρ is near π, while for others it can vary by significant factors. This divergence from an exact π phase change on reflection has little effect on the present invention since its effect is to slightly shift the value of the thickness t required for constructive or destructive interference at a given wavelength, through the addition of an error factor viz. (for constructive interference) ##EQU11## In practising the invention, as discussed below, one simply adjusts t to compensate for the Δt p error (if significant). A similar correction exists for variations in reflectivity but is of no consequence to the present invention since it is basically an angle of incidence correction to reflectivity and we are primarily concerned with normal incidence. As shown by equation (1) and similar formulae, constructive and destructive interference coloring effects will be apparent at non-normal angles of incidence which will vary from those at normal incidence, but this has no effect on the practice of the invention. Referring to FIG. 5 (b), for phase change of ±π, the first internally reflected ray R 2 is in phase with R 1 at λ c given by equation (5) and has an intensity of (100-3.5)%×90%×(100-3.5)%=96.5%×90%×96.5%=83.81% of the original intensity. R 3 is out of phase with R 1 and R 2 and has an intensity of 96.5%×90%×3.5%×90%×96.5%=2.64%. R 4 is in phase with an intensity of 96.5%×90%×3.5%×90%×3.5%×90%×96.5%=0.083%. The sum of R 1 , R 2 , R 3 and R 4 (ignoring higher components) is therefore 3.5+83.81-2.64+0.083=84.75% One cannot readily state what the reflected amplitudes are for wavelengths other than the coherent value since they depend critically on wavelength, materials etc. However, in general, considering R 2 as the primary ray because of its intensity, (R 1 +R 4 ) and R 3 will tend to cancel because of the corresponding phase differences so that the intensity variation cannot be greater than approximately 83.81±[(3.50+0.083)-2.64]=84.75 to 82.87 As a rough approximation, the maximum differential effect is given by the value for λ c minus the lowest value above, i.e. I c =84.75, I B =82.87 and ##EQU12## A special case can occur if the thickness t is such (see later discussion) that destructive interference at λ D can occur simultaneously with constructive interference at λ c . Should such occur, R 2 , R 3 and R 4 for λ D are all in phase with each other and out of phase with R 1 since each additional internal reflection traversal adds 2π to the phase (additional half wavelength due to path length plus π phase change at glass-metal interface). The amplitude for this value of λ D is given by (83.81+2.64+0.083)-3.5=83.03% which gives less than the maximum differential effect calculated above for "random" wavelengths. Interference colors on such highly reflecting metal surfaces therefore tend to be weak or washed out to the eye because of the small differential intensities involved. With the foregoing as background, the operation of the present invention may be readily understood. Consider the situation shown in FIG. 6(a) where the arrangement is the same as that in FIG. 5 (b) except that the metal layer 9 is only 20% reflecting (again assumed flat across the visible spectrum). For a thickness t corresponding to constructive interference at λ c , the intensities and phases of the reflected rays are R 1 =3.5% (initial), R 2 =18.62% (constructive), R 3 =0.13% (destructive) with the higher orders being insignificant. The total reflected intensity at λ c is therefore 3.5+18.62-0.13=22% In general, for other "normal" wavelengths the effects of R 1 and R 3 may be approximated (considering R 2 as the main reflected ray) by assuming that they will add half their difference in intensity to R 2 (i.e. 1/2(3.5-0.13)=1.69%) so that the total intensity R 1 +R 2 +R 3 may be estimated as 18.62+1.69=20.31. The differential effect for λ c above these wavelengths is therefore ##EQU13## compared to the -2.2% found for the opaque reflecting metal case shown in FIG. 5(b). More importantly, if a simultaneous destructive interference occurs at λ D at the same value of t, the minimum amplitude is given by (R 2 +R 3 )-R 1 or (18.62+0.13)-3.50=15.25% In this case the differential effect ##EQU14## or 44% above background which is roughly 20 times that found for the opaque reflecting metal (90%) situation in FIG. 5(b). For comparison, FIG. 6(b) shows the values for a 30% reflecting layer 10. In this case the intensity at λ c is given by (R 1 +R 2 )-R 3 . Since R 1 =3.5%, R 2 =96.5%×30%×96.5%=27.94% and R 3 =96.5%×30%×3.5%×30%×96.5%=0.29%, then the intensity is 3.50+27.94-0.29=31.15% at λ c ; 27.94+1/2(3.5-0.29)=29.54% for an average noncoherent λ A ; and (27.94+0.29)-3.50=24.75% for a destructively interfering λ D . The differential effects are therefore ##EQU15## These are considerably smaller than for the 20% reflecting layer case but are still much larger than the ≈2.2% found for the 90% reflecting case or for the simple glass on plastic case. One of the basic elements of this invention is therefore the adjustment of the thickness of the dielectric medium (glass in examples) used as an interference layer, and the reflectivity of the semi-reflecting metal layer to enhance and/or optimize the differential coloring effect. If one goes to reflectivities less than 20% the effect is enhanced still more, with, for example, the differential effect (both λ c and λ D occurring simultaneously) being >100 at 10% reflectivity. At higher reflectivities than 30%, the effect, of course, decreases in intensity. In examples given, SiO 2 (n=1.46) has been used as the interference dielectric since this material has been extensively used in demonstrating the invention. The differential effect can be increased still further, however, by using other dielectrics having higher values of n, thereby affecting the reflectivities (particularly at the front surface) and ultimately the differential effect. Consider FIG. 7 which gives the situation comparable to that shown in FIG. 6(a) (20% reflecting metal) but with TiO 2 having n=2.60 replacing the SiO 2 as the interference medium. In such a case R 1 =19.753% by equation (3), R 2 =80.247%×20%×80.247%=12.8792%, and R 3 =80.247%×20%×19.753%×20%×80.247%=0.5088%. Considering only R 1 , R 2 and R 3 the enhanced intensity I c =(R 1 +R 2 )-R 3 =(19.753+12.8792)-0.5088=32.1234 and the background intensity I B =R 1 -(R 2 +R 3 )=19.753-(12.8792+0.5088)=6.3650. The maximum differential effect is given by ##EQU16## which is nearly a factor of 10 greater than in the 20% reflecting SiO 2 dielectric case. One could therefore reduce the reflectivity of the metal even more to allow much more of the light to penetrate to the inside while still maintaining a very strong coloring effect. (The limiting factor will be the increased reflectivity at the glass plastic interface as the metal is made less dense and the relative index of the glass and plastic becomes larger leading to increased reflectivity. Exact values depend on a given application and materials). The maximum effects, of course, exist when the sum of R 1 and R 2 is much greater than their difference as in the above TiO 2 case. In general, this occurs when the index of refraction of the dielectric has a relatively (compared to SiO 2 ) high value. Another example is Si 3 N 4 which has n=2.03 resulting in a maximum differential effect of 503%. Other materials such as SiO (n=1.95) and Al 2 O 3 (n=1.76) will have coloring effects which are more pronounced than those of SiO 2 and others will be apparent to those skilled in the art. The choice of material depends on the particular application. In the discussions which follow, the SiO 2 situation is the one which is considered in all cases. For the non-opaque, semi-reflecting metal cases, white light incident upon and penetrating through the rear surface and emerging through the front tends to decrease the effect. The major decrease is due to an increase in the background level since interference effects that occur in the thin glass layer (i.e. interference effects between light reflected at plastic-metal interface and that reflected at glass-air interface) will be non-coherent with those occurring due to light incident on the front and even if occurring will have a much smaller effect due to the much higher background. The latter results because the transmitted light differential effect is the complement of the reflected light effect and is superimposed on a much higher background (80% of light reaching plastic-metal interface minus 3.5% reflected at glass-air interface). Considering only the increase in background, if white light of intensity 100% of I(intensity of white light on front surface) is incident on the rear surface in the 20% reflectivity (metal) case, approximately 74.5% (after three reflective losses at various interfaces) will exit through the front surface. The effect in the maximum differential case (λ c +λ D simultaneously) is a reduction from 44% to a value of ##EQU17## Although in a practical embodiment of the invention (e.g. use as sunglasses) there is much less than 100% of I coming through the rear surface, even in the worst case of 100% of I the differential effect is much greater than that obtained (˜2.2%) for a 90% reflecting layer case. This negative effect of white light penetrating through the rear surface can be partly negated by having the substrate (plastic in example) made of visible light absorbing material. If, for example, the plastic in the 20% reflecting case were of a thickness and absorptivity A to be 50% absorbing in the visible, white light of intensity I entering through the rear surface would have an intensity of 0.371(1×0.965×0.5×0.8×0.965) on exiting through the front surface and the maximum differential effect (λ c +λ D simultaneously) would be ##EQU18## In the real case of sunglass use, the light entering through the rear is much less, say 20% of I maximum, being only that going around the frames and reflected off the skin. For this value the maximum differential effect equals approximately 22% for the non-absorbing substrate use and 29.8% for the 50% absorbing substrate case. Since the thickness t of the interference medium (glass in example), the reflectivity R of the reflecting metal; the absorptivity A of the substrate material and the ratios thereof are infinitely variable, within the limits of minimal reflectivity (no metal) and no absorption (clear substrates) and maximum reflection (opaque polished or evaporated metal) and maximum absorption (highly absorbing substrate), the color and/or intensity of the structure as viewed by an observer on the front or incident surface and that of the light reaching a viewer behind the rear surface (wearer for sunglasses) can be varied over an extremely broad range. In the practical embodiment of the invention, this allows the user to reduce the light reaching the inside viewer to a desirable level, e.g. 30% of neutral or near neutral shading for a sunglass wearer, while obtaining the desired color and intensity level for an external viewer. It has been demonstrated in practising the invention that neutral shading can be obtained by having a substrate having neutral absorption at the proper level. This can be used to overcome or wash out coloring effects due to light coming from the front surface (non-reflected) which is the complement of that reflected and is therefore colored, although of much less effective density than the reflected component because of the much higher background (˜74% of light being transmitted in 20% reflecting and non-absorbing substrate case). The light reaching the inside receiver can also, of course, be colored if desired. A, R and t etc. may be adjusted to yield other values of external coloring and intensity etc. for other purposes, e.g. for office windows. For this use, in one test of the invention the absorbing substrates were of glasses manufactured by PPG Industries, Inc. under the names solarbronze, solargray and solarex. The metal layer reflectivity was adjusted to reduce the light level penetrating to the inside to a comfortable level while maintaining the neutral characteristics (particularly for solarbronze or solargray) and changing the color as viewed from the outside to that desired but for this purpose deliberately of less intensity than in the normal sunglass case. However, it should be noted that all ranges of values for external color intensity and transmitted light intensity may be used for any and all applications. Of course, in a limited number of embodiments of the invention (such as wall panels, etc.) the transmitted light intensity may be of no consequence. A very important factor that is observed in the practical embodiment of the invention is that the colors so formed have an extremely metallic appearance; i.e. a metallic nature similar to that obtained with a highly polished metal reflector such as Al, but with deep color shading resulting in a striking "colored metallic" appearance. This occurs because the differential effect primarily results from reflection at a very thin layer in the same way that reflection results at the surface of a neutral metal reflector. The resulting radiation is therefore space as well as time coherent and the eye perceives that the light emanates from a restricted layer or layers. (This is in contrast, for example, to absorbing glasses which have a color due to absorption and reemission of radiation at many spatially separated atomic layers in the glass and which therefore do not have a metallic appearance). This factor when optimized by proper use of the present invention gives a recognizable and distinctive appearance when A, R and t etc. are chosen for vivid coloring. The practice of the invention can best be understood and mastered by a full appreciation of the effect of using a partially-reflecting metal layer as discussed previously in conjunction with Table I which gives the colors observed by previous investigators (Pliskin and Conrad-IBM Journal, January 1964) for thermally grown films of SiO 2 on polished (i.e. opaque maximum reflecting) slices of silicon. The latter is the case normally observed previously, where the coloration is not enhanced nor has a strong metallic appearance as in the present invention. Similar, but not exactly the same, colors were observed in the practical demonstrations of the present invention. Exact coloring depends on the metal used as the reflecting layer and varies in each case. Table I has been prepared specifically for this invention to explain the colors obtained and to show detailed operation. It gives the calculated wavelengths for constructive interference ##EQU19## and destructive interference ##EQU20## in association with the colors observed by Pliskin and Conrad. Note that the value of t given is the real value, not the optical thickness tn g and the λ c 's and λ D 's having effects in the visible are outlined. At 500 Å, there is no visible wavelength λ c or λ D at which interference effects should occur if the glass (SiO 2 ) has an index of refraction of ˜1.46 (used for calculating Table 1). The tan color observed by Pliskin and Conrad can be explained by the following considerations. If the SiO 2 is oxygen deficient and has an appreciable proportion of SiO having an index of refraction of 1.95 (or other oxygen-deficient SiO x compounds) as can occur at the interface for thin thermally grown SiO 2 layers on Si, the λ D for destructive interference (m=o) is 3,900 Å which is above the edge for optical interference (˜3,800 Å) in the visible. Some of the violet component will be removed from the reflected light under these conditions, so that the remaining reflected light has a tan appearance or color as observed by Pliskin and Conrad. However, for n=1.46 which is obtained if the silicon is deposited by ion beam sputtering or ion beam implantation sputtering techniques, no tan color is apparent when layers of 500 Å thickness are deposited on highly reflective metal layers such as opaque ion beam sputtered Al on smooth glass or plastic substrates. Such layers, if hermetic as in the ion beam sputtering case, can be used to protect the reflecting metal against corrosion etc. without altering its optical characteristics at wavelengths longer than ˜3,000 Å. This has been clearly demonstrated for the present invention. If the thickness is increased to 700 Å, λ D becomes 4,088 Å, moving the removed (i.e. destructively interfered) component farther towards the blue, producing a brown appearance. At 1,000 Å, λ D is 5,840 Å which is in the yellow part or middle of the spectrum. Both ends of the spectrum therefore show up in the reflected light which is dark violet to red-violet. At t=1,200 Å the red end of the spectrum is removed and the reflected light centers around the blue region. These results are confirmed by Pliskin and Conrad's observations, and one can assume that for these thicker layers the problem of oxygen deficiency at the interface is relatively less severe. At approximately 1,300 Å thick, a new effect occurs; i.e. "constructive" interference at 3,800 Å with the first corresponding value in the table being a λ c of 4,380 Å for t=1,500 Å. For this value of t, the coloring is primarily due to constructive interference rather than destructive effects so the reflected light has a color (light blue) dominated by λ c . In fact the royal blue observed at 1,200 Å probably has a constructive component in the deep violet due to the spread around λ c (see FIG. 3(b)) and the extension of enhancement effects to higher and lower values of λ than the precise value λ c . In addition, because of the spatial as well as time coherent nature of the reflected light, it assumes a metallic appearance which is also observed at t=1,700 Å and 2,000 Å. However, these effects for opaque maximum reflecting substrates as in the Pliskin and Conrad case are very small and disappear at larger values of t, but are very prominent and continue throughout the large values of t if the present invention is practised to produce large differential effects as discussed previously. Also beginning at t=2,000 Å is a definite simultaneous occurrence of λ c and λ D . At t=2,200, λ c =6,424 Å while λ D =4,283 Å so the reflected light is enhanced around λ c and has a decreased value around λ D , the resulting color being a combination of the two effects, or gold with slight yellow orange for this example. Using the present invention, the enhancement of the color through the differential effect plus the spatially coherent nature of the reflected light results in a "strong" metallic appearance for all colors corresponding to thicknesses greater than 1,300 Å. This metallic appearance and strong coloration continue until the thickness is such that there are so many interference effects occuring simultaneously at different λ c 's and λ D 's (i.e. for different values of m-see Table 1) that the resulting reflected light again tends to white (e.g. in Table 1, for t=15, 400 Å, there are 6 λ c 's corresponding to m=6, 7, 8, 9, 10 & 11 and 6 λ D 's corresponding to m=6, 7, 8, 9, 10 and 11). Above >15,000 Å the interference colors become hard to observe on opaque maximum reflecting substrates although still easily observed on the partially-reflecting substrates of the present invention because of the color enhancement. From Table 1, one can also see that for the values of t which would be used in practising the invention, there are values of λ c and λ D corresponding to effects in the IR (infrared) and UV (ultraviolet) regions of the spectrum. Such effects are discussed below in connection with an important variation on the invention. Table 1 allows the user to choose the correct values of t to practise and optimize the effects of the present invention when used in conjunction with appropriate reflectivity calculations. No precise format can be given for the latter since it depends on factors (e.g. light levels, color density, means of depositing materials etc.) which must be chosen for a given application. The most enhanced colorations are obtained for one or two orders of λ c combined with one or two orders of λ D which in general applies for t between 1,500 Å and 6,000 Å. This is not rigid, since the coloration depends on other factors such as reflectivity, absorption in the substrate, type of reflecting metal etc. but serves as a guideline for easiest practice of the invention. SiO 2 layers of this thickness are also found to supply adequate chemical and mechanical protection for the underlying metal and/or plastic in many applications (e.g. sunglasses or windows). Another variation which can be used to extend the range of colors obtained by the present invention is to use an absorbing dielectric medium for the interference dielectric, on the front surface. The color thus obtained is a combination of the interference effect and the absorption and reemission effects in the interference dielectric. It should also be noted that light penetrating from the rear through an absorbing substrate will affect the coloring to an extent depending on the intensity of the rear light and the color of the absorbing substrate. The latter may be used to modify the color or to "mute" the metallic effect in applications such as office building windows. Another variation is to choose the partially-reflecting metal from those that do not have near constant reflectivity across the visible spectrum but which have varying R. An example is copper which has a reflectivity of ˜58% at 4,500Å and ˜97% at 7,000Å. This difference in reflectivity can be used further to enhance certain colors, e.g. red tones, because of their obvious enhancement of the differential effect due to the difference in reflectivity. Gold, nickel, and brass are other examples of such metals or alloys. Others will be obvious to those skilled in the art. A most important variation of the invention is obtained by extending its application to other wavelengths outside of the visible, in particular into the infrared (IR) region. This is of special importance for windows designed to reduce or control the amount of radiant heat (from sun, atmosphere, or other hot sources such as other buildings etc.) entering the building in order to conserve energy by reducing the air conditioning load. In order to optimize this saving, it is desirable that any optical layers used to reflect or reject the incident IR radiation be on the outside surface of the window. If applied to the inside, much of the incident IR radiation will be absorbed in the glass itself, either on the first pass through or on the second pass after reflection, thereby heating up the glass. Much of this heat in the glass is then transferred into the interior of the building by convection currents of the internal air or by reradiation at longer λ's. Applied to the outside, such reflecting layers are therefore more effective in summer but are still effective in preventing heat losses in winter since the IR energy radiated by internal objects will either be absorbed in the glass, and partially returned to the room by convection etc., or for the portion that passes through the glass to the metal layer, will be reflected back and absorbed in the glass or returned to the room. With the present invention, this control of the IR radiation entering or leaving the inside of the building can be effected while still controlling the visible light entering the building and also the external and internal coloring effects. This capability results from the longer wavelengths of the IR radiation. By reducing the thickness of the partially reflecting metal layer, one can control the amount of visible light entering the building for lighting needs (e.g.≈50% of incident light for R≈20% and 40% absorbing substrate), while achieving the condition for optimizing color effects as discussed previously, and maintaining a high IR reflectivity. In demonstrating this invention, it has been demonstrated that this combination can be achieved if the partially-reflecting metal is one of inherently high IR reflectivity which is put down by a technique or process (such as ion beam sputtering) which provides uniform dispersion of the metal without appreciable agglomeration. At thicknesses where the layer looks relatively open to visible λ's, the same partially-reflecting layer looks relatively opaque to the IR λ's since their size is such that they intercept more of the metal atoms on the average, leading to increased reflection. In practice, visible reflectivities have been reduced to the 20-50% range in the visible, while maintaining the IR reflectivity at >70% and as high as 95% in the near (e.g. 2.5μ) and far IR (e.g. >10μ). An important region for control of heat load on buildings is below 2.5μ for air conditioning requirements (most of heat incident from outside) since the terrestrial solar spectrum is such that approximately half of the sun's radiation is in the visible and half in the near IR (below 2.5μ). However, the buildings also receive longer wavelength (4-100 microns with maximum intensity near 10 microns) radiation from the atmosphere which also exerts a heat load. For winter conditions, where one wants to prevent radiation of heat from internal bodies with temperatures of ˜25°-30° C., the far IR characterized is important since the peak of the black body radiation spectrum for a body at 28° C. is approximately at 10μ. It is therefore desirable that the reflectivity be high across the IR spectrum. This has been demonstrated with the present invention using Cu or brass as the reflecting metal, both of which have higher reflectivity at the longer visible λ's than at the shorter end of the spectrum. The value of reflectivity can thus be adjusted to give relatively high IR reflectivity, including the region from 8,000 Å up to 2.5μ (25,000 Å) while keeping the average visible light reflectivity low. Other materials such as Au and Ag etc. may be used to achieve the desired function but are relatively expensive and for many application methods difficult to deal with. As evident from Table 1 and discussed previously, interference effects also occur in the IR as well as in the visible for interference layers of interest for coloring effects. These interference effects in the IR are, however, of much less importance since the IR reflectivity is high (for properly chosen metal layer) with or without interference effects, and differential effects are relatively unimportant. In demonstrating the present invention, ion beam sputtering and ion beam implantation sputtering have been used. However, any process that is capable of putting down the necessary materials in the necessary form may be used without affecting the operation of the invention. The deposition technique used in demonstrating the invention can also put down materials such as Au or Ag on both glass and/or plastic as well as other materials without intermediate or bonding layers, as required with many other techniques (e.g. evaporation). This is important in achieving the correct degree of reflectivity for proper operation of the invention. More importantly, it is of utmost necessity that the glass interference layer over the metal layer protect the metal layer from chemical (environmental) and mechancial (cleaning etc.) attack as well as providing the necessary interference function. This is only possible if the glass is impervious to chemical vapors or liquids in very thin layers, is mechanically hard and is of optical quality. Ion beam sputtered fused SiO 2 has been used to demonstrate the invention since it meets all of these requirements because of its unique characteristics. However, any other method of applying the interference glass with the necessary characteristics will result in successful operation of the invention. It is important that the glass layer be applied immediately over the metal layer and in such a manner that the metal does not oxidize or otherwise alter its reflecting state. If, for example, the metal is a freshly deposited layer of Cu, and it is exposed to air or O 2 for an appreciable time before the hermetic interference layer (or equivalent) is applied, the Cu will oxidize and the reflectivity will decrease, affecting the visible coloration, reflected and transmitted light intensities and IR rejection capability. If the glass is not hermetic, the characteristics of the structure will degrade with time. Au is not subject to severe degradation but is relatively expensive and for some application techniques difficult to apply. Application of the hermetic seal immediately over the reflecting layer can be used to provide very thin (500 Å or less) non-colored protective layers if the applied glass is impervious to chemical attack in thin layers. As discussed previously, the coloration observed by Pliskin and Conrad at 500 Å may be due to inadequate characteristics of the glass layer. The use of such thin layers avoids the expense of applying thick layers (>2μ) to eliminate interference color effects. This innovation has been demonstrated and is of importance for protecting front surface mirrors while maintaining optical characteristics, for applications such as optical instrument mirrors and concentrators for energy conservation and generation systems, for hermetically sealing solar cells for terrestrial applications etc. Another variation of the present invention is its use on plastic substrates, both absorbing and non-absorbing at visible λ's, to provide IR rejection. Whereas glass substrates, in many practical areas of interest such as sunglasses, absorb some of the incident IR, plastics in general do not. Thus wearers of plastic sunglasses are subjected to IR heating of the eye, leading to drying out of the membranes and irritation, even if the glasses are adequate for visible radiation purposes. The present invention avoids this effect through rejection of undesirable IR radiation while controlling visible light and coloring effects at desirable levels. With the metal applied as a thicker highly reflecting opaque layer, "plastics" can also be used as excellent visible plus IR mirrors and concentrators etc. for solar energy generation and conservation systems, with the metal layer protected by a thin (˜500 Å) hermetic and mechanical seal as discussed previously. These effects have been demonstrated. Still another variation of the invention is its use to produce coloring effects in wall panels, etc. without regard to transmission properties. Having thus described the principles of the invention, together with several illustrative embodiments thereof, it is to be understood that, although specific terms are employed, they are used in a generic and descriptive sense and not for purposes of limitation, the scope of the invention being set forth in the following claims. TABLE 1__________________________________________________________________________Color__________________________________________________________________________Tan 500Brown 700Dark Violet to Red-Violet 1,000Royal Blue 1,200Light Blue to Metallic Blue 1,500Metallic to very light Yellow-Green 1,700Light Gold on Yellow - slightly metallic 2,000Gold with slight yellow-orange 2,200Orange to Melon 2,500Red-Violet 2,700Blue to Violet-Blue 3,000Blue 3,100Blue to Blue-Green 3,200Light Green 3,400Green to Yellow-Green 3,500Yellow-Green 3,600Green-Yellow 3,700Yellow 3,900Light Orange 4,100Carnation Pink 4,200Violet-Red 4,400Red-Violet 4,600Violet 4,700Blue-Violet 4,800Blue 4,900Blue-Green 5,000Green (broad) 5,200Yellow-Green 5,400Green-Yellow 5,600Yellow to "Yellowish" 5,700Light Orange on Yellow to Pink borderline 5,800Carnation Pink 6,000Violet-Red 6,300Bluish (borderline violet to bluegreen - appears greyish) 6,800Blue-Green to Green (quite broad) 7,200"Yellowish" 7,700Orange (rather broad for Orange) 8,000Salmon 8,200Dull, light red-violet 8,500Violet 8,600Blue-Violet 8,700Blue 8,900Blue-Green 9,200Dull Yellow-Green 9,500Yellow to "Yellowish" 9,700Orange 9,900Carnation Pink 10,000Violet-Red 10,200Red-Violet 10,500Violet 10,600Blue-Violet 10,700Green 11,000Yellow-Green 11,100Green 11,200Violet 11,800Red-Violet 11,900Violet-Red 12,100Carnation Pink to Salmon 12,400Orange 12,500"Yellowish" 12,800SkyBlue to Green-Blue 13,200Orange 14,000Violet 14,500Blue-Violet 14,600Blue 15,000Dull Yellow-Green 15,400__________________________________________________________________________λ.sub.ct (A)m = 1234567891011__________________________________________________________________________ ##STR1## ##STR2## ##STR3## ##STR4## ##STR5## ##STR6## ##STR7##__________________________________________________________________________λ.sub.Dt (Å)m = 01234567891011__________________________________________________________________________ ##STR8## ##STR9## ##STR10## ##STR11## ##STR12## ##STR13## ##STR14##__________________________________________________________________________
A window achieves broad band infrared reflection with a thin reflective layer and a clear interference coating on its outside surface. Color viewed from outside is enhanced by varying the thickness of the interference coating, while the window still exhibits neutral color to transmitted light. The reflective layer is formed of a metal such as copper, gold or copper alloy to provide enhanced IR reflection extending beyond ten microns. The metal is preferably deposited without agglomeration, and with uniformity that permits high and neutral transmission of visible light.
Briefly describe the main invention outlined in the provided context.
[ "This application is a continuation of U.S. patent application Ser.", "No. 430,080 filed Nov. 1, 1989 entitled LIGHT CONTROL WITH COLOR ENHANCEMENT now U.S. Pat. No. 5,054,902 which was a continuation of Ser.", "No. 921,312 (now abandoned) filed Oct. 21, 1986 as a continuation of Ser.", "No. 223,840 (now abandoned) filed Jan. 9, 1981 which was a continuation of Ser.", "No. 645,262 (now abandoned) filed Dec. 29, 1975 each of these patent applications being titled LIGHT CONTROL WITH COLOR ENHANCEMENT.", "BACKGROUND OF THE INVENTION The invention relates to the enhancement of color by means of the optical interference effects which are produced by thin films.", "Interference phenomena in connection with thin films are well known.", "A summary of some of these phenomena is set forth in an article in the Scientific American entitled "Optical Interference Coatings", December 1970, pages 59-75.", "Although the article starts with a display of various colors in a colored illustration and includes references to certain color effects produced in nature by thin films such as oil slicks, soap films, oyster shells, and peacock feathers, the various scientific uses of optical interference coatings described in the article do not include the conscious production of visual color effects.", "A major use of optical coatings is the production of reflection or non-reflection across the visible spectrum.", "Thus anti-reflection coatings are used on lenses, and multiple reflective coatings are used in dielectric mirrors.", "Applications requiring enhancement at a particular wavelength have an analytical rather than a visual purpose and require the maximum reflectivity possible, such as the laser and the Fabry-Perot interferometer.", "Although the Plumbicon tube separates light into primary colors, these are not viewed, but produce signals for transmission to a receiver via megacycle carrier waves.", "Moreover, not only do these prior scientific uses of optical interference films have no visual purpose, but the way in which the films are used to achieve a particular effect is such that, once adjusted for this effect, the optical device in question can no longer be adjusted to control other parameters.", "Various methods have also been used to alter the spectral transmission and other characteristics (absorption, color etc.) of materials such as glasses or plastics in order to make them useful as sunglasses, either as light absorbers to reduce and/or control the amount and nature of light reaching the eye, or for cosmetic reasons.", "These methods have included coloring the basic materials, adding a colored layer over the surface, adding a neutral filter to one or more surfaces, adding a polarizing material, etc.", "However, the application of interference films to provide interference colors has not normally been used for such purposes.", "Such colors, although observed by many investigators, have not been used in general for cosmetic purposes because of difficulties in obtaining "predetermined"", "colors and because the colors lacked "depth", particularly on the transparent or partly absorbing substrates that are used for sunglasses and similar purposes.", "It is the purpose of this invention to show how such colors can be obtained having "depth"", "or color "density"", "under controlled conditions.", "In addition, this invention shows that such "high depth"", "colors can be obtained under conditions which allow the user to control the amount and nature of light transmitted to and through the substrate.", "This invention will also show how the latter control of the transmitted light can also be obtained while having "low depth"", "coloring.", "In fact, any practical degree and/or combination of color depth and transmitted light control can be obtained by proper use of the present invention.", "In conventional optical techniques, interference films are commonly used to fabricate band-pass light filters and to "increase"", "(as distinct from the invention's effect, which is always to decrease the transmitted light, as in the case of sunglasses and other light reducing devices) the amount of transmitted light (for lenses, binoculars, etc.) through their use as so-called quarter-wavelength anti-reflection filters, the latter being a simple form of the former.", "As discussed below, since any film of "optical"", "thickness λ/4 (λ being the wavelength of the radiation) is effective only around one value of λ (or specific functions thereof), the application of such films having λ values in the visible range causes the reflected and transmitted light components to be colored, even when the incident light is white, as is usually the case for sunglasses, windows etc.", "By choosing film thicknesses properly, one can get a wide spectrum of reflected colors (the color of the transmitted light being the spectrum of the incident light, normally white, minus the reflected and absorbed components).", "This technique has not normally been used as a "coloring"", "mechanism primarily because of difficulties in controlling the color and very importantly because of the lack of intensity or color depth when used on transparent or partly absorbing substrates.", "In fact, such colors are normally observed only as a necessary adjunct to other factors such as the need for an anti-reflection filter on binoculars.", "The lack of color depth (pastel shading in general) is acceptable for some purposes (e.g. lightly tinted sunglasses) but is not adequate for others.", "Another reason why interference techniques have not been put to widespread commercial use is the need to put such films on the outside of the lens (or window etc.) for best cosmetic effect or function.", "In practice, this means the films themselves must be quite hard or must be covered with another harder (normally transparent) film or layer to prevent scratching or other attack, thereby complicating the manufacturing process.", "The use of interference films has therefore been primarily restricted to optical instruments (binoculars, spectrometers, etc.) and techniques (band pass filters, etc.) where such factors are relatively unimportant because of the care which the optical components receive and/or the undesirability of or lack of need for coloration.", "In fact, in many scientific instruments which use interference effects for measurement purposes, monochromatic light must be used at some stage to provide the necessary operation.", "For most such purposes, conventional interference techniques are adequate.", "However, in the case of plastic eyeglass lenses (both prescription and sunglass) there is a need for a coloring technique which can provide vivid cosmetic colors and also give protection to the soft plastic surface while providing the light reflection and/or absorption necessary to perform a worthwhile sunglass function.", "Similar applications exist in plastic windows, plastic decorator panels or building materials, etc.", "and also for other substrate materials (e.g. glass) in special applications (decorator panels or functional windows, etc.) Other applications will be obvious to those skilled in the art who become familiar with this invention.", "Some of such applications may simply require a color effect without the need to adjust other parameters such as light transmission.", "For example, such applications as plastic wall panels protected against scratching, costume jewelry, decorative dishes, bottles, and the like may incorporate the principles of the invention simply for a coloring effect.", "In these applications, the interference coloring film must usually be extremely well bonded, to a degree not normally achieved with standard deposition techniques.", "Although any "appropriate"", "process capable of attaching the required materials in the "required"", "form to the substrate surface may be used in applying this invention, the invention itself has been demonstrated using ion beam sputtering and ion beam implantation sputtering techniques.", "The former is disclosed, for example, in U.S. Pat. No. 3,472,751.", "The latter is disclosed in my Disclosure Document No. 032867, filed Jun. 5, 1974, and can be used to deposit very tightly bonded, durable films on plastics and other difficult substrates, the film of deposited material commonly, but not necessarily, being harder than the substrate material.", "SUMMARY OF THE INVENTION The invention deals with transparent solids such as windows, eyeglasses, etc.", ", (and, in certain embodiments, coloring effects on solids whether transparent or not, such as wall panels, costume jewelry, etc.) and provides means for enhancing color of light incident upon the transparent solid while at the same time permitting further control of the radiation transmitted and reflected over a wide spectrum.", "The invention makes use of the discovery that the color of the reflected or the transmitted light may be enhanced in a way which does not materially affect the bulk of the visible light passing through or reflected by the transparent solid.", "In accordance with the invention color enhancement is achieved by interference between light reflected from a semi-reflecting layer on the transparent solid and light reflected from the outer surface of a dielectric layer which is hermetically sealed over the semi-reflecting layer.", "The reflectivity at each of these surfaces need not be particularly large since color enhancement is achieved by a differential effect whereby the eye detects either the prominence of constructive interference at a particular band of wavelengths over the background radiation, or the color effect produced when a band-width of light is removed from the reflective light by destructive interference.", "In each case the bulk of the radiation is not affected by the interference phenomena, so that the light transmitted through, reflected by, or absorbed in the transparent solid may still be controlled by varying the thickness of the semi-reflecting layer and by other means.", "BRIEF DESCRIPTION OF THE DRAWING The invention may best be understood from the following detailed description thereof, having reference to the accompanying drawings, in which FIG. 1 is a diagrammatic sectional view of a series of layers arranged in accordance with the invention;", "FIG. 2 is a view similar to that of FIG. 1 showing the transmission and reflection of light rays incident upon a glass layer in air;", "FIGS. 3(a)-3(c) are a series of graphs showing the effect of superimposition of waves;", "FIG. 4 is a view similar to that of FIG. 2 wherein the glass layer is supported upon a plastic substrate;", "FIGS. 5(a) and 5(b) are a series of views similar to that of FIG. 2 showing the reflection of light rays incident upon a highly reflecting layer;", "FIGS. 6(a) and 6(b) are a series of views similar to those of FIG. 5 showing the reflection of light rays incident upon a semireflecting layer in accordance with the invention;", "and FIG. 7 is a view similar to those of FIG. 6 wherein glass of a relatively high index of refraction is used.", "DESCRIPTION OF PREFERRED EMBODIMENTS The primary aspect of this invention is the means of obtaining on suitable substrates, optical layers which with reflected light, i.e. to the viewer on the side of the incident light, have a "colored"", "metallic appearance as opposed to the conventional neutral metallic appearance normally used in sunglasses, mirrors, etc.", "A second aspect is the means to obtain optical layers which control the characteristics of the visible light and/or other radiation reaching a viewer on the opposite side of the substrate from the incident visible light and/or other radiation (hereinafter collectively referred to as radiation), while simultaneously controlling the "color"", "of the composite structure as viewed by an observer on the side of the substrate upon which the radiation is originally incident.", "A third aspect is to "control"", "the transmitted radiation and colors as in the second aspect above while simultaneously controlling the amount and type of incident radiation which is absorbed in the original substrate, by controlling the amount of incident radiation which is reflected away from the substrate direction.", "A fourth aspect is to obtain the functions above while simultaneously protecting the underlying substrate and deposited material from mechanical and/or chemical attack.", "The physical arrangement required in accordance with the invention to obtain all of the above functions is shown in FIG. 1. The important feature of this arrangement is the combination of a partially-reflecting or so called semi-reflecting (reflectivity being less than a highly polished or deposited "opaque"", "metal layer and more than a low reflectivity substrate such as clear glass or plastic) layer 1 and a layer 2 of transparent or "partially"", "absorbing material (such as clear or colored glass, respectively) with index of refraction and thickness appropriate to obtain the desired features of the invention.", "How this combination differs from conventional interference methods and how it works in practice are described below.", "If necessary, a second layer 3 of transparent or partially absorbing material can be put over the interference layer 2 to provide additional protection and/or coloring effects in conjunction with those due to the interference layer.", "The semi-reflecting layer 1 is itself supported on a suitable underlying substrate 4.", "The operation of this invention and the differences with respect to previous methods can best be understood by comparison with classical optical theory and practices related to interference effects due to thin films.", "This can be done in stages as shown in FIGS. 2-6.", "The incident light may be incident at any angle θ from 0° to 90°.", "However, in the following discussion, unless stated otherwise the light is considered to be incident normal to the surface (i.e. θ=0°) to simplify and clarify the description of the invention.", "The light rays in FIGS. 2, 4, 5, and 6 are shown at an angle θ≠0° for purposes of ray identification and only the reflected rays of interest are shown.", "The corresponding transmitted rays are the incident rays minus the reflected component.", "If the substrate medium is absorbing (e.g. colored glass) the final transmitted ray would also be minus the absorbed component.", "Unless otherwise stated, all dielectric materials shown are non-absorbing and are assumed to have indices of refraction that are constant across the visible spectrum.", "The first element in defining the invention is a simple very thin (e.g. <10,000 Å thick) film 5 of glass suspended in an air medium as shown in FIG. 2. This is analogous to the classical soap film in which interference colors are observed corresponding to discrete film thicknesses t. In general, there is a phase change of ±π if a light wave travelling in a medium with a given index of refraction is reflected at the interface with a medium having a higher index of refraction and the phase change is 0 if the reflecting medium has a lower index of refraction than the original medium.", "This assumption is not rigorously true for many cases of reflection at the boundary of two different media, for example at many air-metal interfaces, but is adequate and convenient for purposes of explanation.", "It is valid for the air-glass-air case shown in FIG. 2. Exact phase changes of 0 or ±π are used below in discussing all of the interfaces in FIGS. 2, 4, 5 and 6 and where this can lead to appreciable difference in operation of the invention, it is discussed.", "In no event does the divergence from a rigorous treatment alter the basic concepts of the invention.", "Since there is a phase change of ±π at the first interface in FIG. 2 and 0 at the second, it can be shown that the first ray reflected from the air-glass interface is reinforced through constructive interference effects at wavelength λ c given by ##EQU1## where t≡thickness of glass n g ≡index of refraction of glass θ≡angle of incidence For θ=0, cos θ=1 and equation (1) becomes ##EQU2## (All subsequent formulae and discussions assume θ=0) Reflectivity at the interface between two non-absorbing media is given by the formula ##EQU3## where n o ≡index of refraction of first medium;", "in this case, air.", "n g ≡index of refraction of second medium;", "in this case, glass.", "For n o =1(air) and n g =1.46(fused silica) R=3.5% Unless otherwise noted it is assumed for purposes of discussion that the reflectivity is the same at all λ's of interest, i.e. n g is constant across the spectrum of interest.", "From FIG. 2 it is seen that the component (R 1 ) reflected from the first air-glass interface has an intensity of 3.5% of the original ray.", "The remaining 96.5% of the original ray is reflected from the rear glass-air interface with an intensity relative to the original ray of 96.5%×3.5%=3.38%.", "At the front surface this internal ray is again reflected (reflectivity=3.5%) with an intensity relative to the original ray of 3.38%×3.5%=0.118% and the remaining 3.38%×96.5%=3.26% emerges as the second component (R 2 ).", "The part of the first internal ray (0.118% of original intensity) which is rereflected at the front surface, will be rereflected from the back surface with an intensity of 0.118%×3.5%=0.00413% and will emerge through the front surface as R 3 having an intensity of 0.00413%×96.5%=0.0040% after an addition 3.5% loss through reflection at the front surface.", "The internal reflections continue with corresponding decreases in the intensity of the rays R 4 , R 5 .", "emerging through the front surface.", "If the first internally reflected ray R 2 is in phase with the originally reflected ray R 1 upon emerging as given by equation (3), the second internally reflected ray (R 3 after emerging) is out of phase since the total additional path length is a 1/2 integral number of wavelengths long and there is no additional phase change at either the front or rear internal reflections.", "The third internally reflected ray (R 4 after emerging) is in phase etc.", "R 1 and R 2 are in phase and of much larger magnitude than the other rays, resulting in an enhancement of the color at the particular wavelength involved (assuming glass thickness t corresponding to constructive interference at visible wavelengths λ c ).", "A rough approximation is a doubling of the energy reflected at λ c as given by equation (3) and shown (for the first two rays R 1 and R 2 ) in FIG 3(a).", "At other wavelengths near the coherent wavelength, the amplitudes can be partially reinforced as in FIG. 3(b) where it is assumed that R 2 is roughly 36° out of phase with R 1 .", "If, however, R 1 and R 2 are π or near π out of phase as in FIG. 3(c), there can be almost complete annihilation of the reflected components at that wavelength.", "The wavelengths λ D for maximum out of phase destructive interference is given by: ##EQU4## Whether major constructive and destructive interference effects can occur simultaneously in the same film and to what extent is primarily a function of the film thickness and is discussed below.", "The net result with respect to the film is an apparent color corresponding to wavelengths around λ c (if constructive interference dominates) or at that color that remains after that corresponding to wavelengths around λ D are removed (if destructive interference dominates).", "These colors for this type of film can be reasonably intense if the film is not exposed to a lot of white light incident on the rear surface.", "Since the transmitted light is the complement of the reflected light, if there were white light incident on the rear surface of intensity level 100% of that incident on the front surface, the two wave trains would tend to complement each other and produce white light as viewed from either side.", "However, if most of the light is incident on the front surface, the "differential"", "effect on the reflected light can be quite significant leading to relatively intense coloring.", "For example, if only constructive interference occurs, those wavelengths near λ C will have an intensity level of R 1 +R 2 -R 3 +R 4 etc.", "≡I c ≈R 1 +R 2 =3.5+3.26=6.76% while those at wavelengths far removed from λ c , where R 2 is half in phase and half out of phase with R 1 will have an intensity I B roughly equal to that of R 1 , i.e. approximately 3.5%.", "A convenient measure of the differential level of the constructive color component above background is the difference between the enhanced intensity I c and the random background intensity I B , divided by the random background intensity I B .", "For the case under consideration this is approximately ##EQU5## if only the reflected components are considered.", "In practice, some white light is incident on the rear surface and the differential effect is much less than this.", "It should be noted that the structure shown in FIG. 2, although producing vivid coloring, is not adequate for most practical purposes because of the thinness of the glass layer involved.", "It should also be noted that the coloring effects are due to the ability of the eye to observe and evaluate the "relative"", "amplitudes of the various components of the light entering the eye, so that the greater the differential height of the coherent λ C (for example above) "above background", the deeper or more vivid will be the apparent color.", "Although the above discussion consists primarily of an analysis of observed facts and in that sense is trivial, it is important to a clear understanding of the present invention as discussed below.", "FIG. 4 gives the next stage in understanding the invention and shows a glass film 5 of index of refraction n g intimately attached by some method to a plastic substrate material 6 having index of refraction n p where n p ≳n g and both media are non-absorbing.", "(The materials chosen here and in subsequent stages of the development are arbitrary and could be replaced with other "suitable"", "materials without altering the basic explanation.) In this case there is a phase change of ±π upon reflection at the front surface and "another"", "phase change of ±π upon reflection at the glass-plastic interface.", "The condition for constructive interference of the first internally reflected ray R 2 with the initial reflected ray R 1 , in this case is given by;", "##EQU6## The condition for destructive interference is given by;", "##EQU7## However, in this case the amount of light reflected from the glass-plastic interface, as given by equation (3) for n g =1.46 and n p =1.54(plastic) is only 0.071%×96.5%=0.0686% of the incident light with the emerging component R 2 only 0.0686%×96.5%=0.0662%.", "The plastic substrate 6 is assumed to be very thick since it must provide support, and so there are no interference effects due to reflection at the rear plastic-air interface.", "This additional light of R 2 , even if satisfying equation (5), will therefore produce a differential effect of only 0.066/3.5=0.019 or 1.9% above background.", "Such combinations of materials therefore have only a very slightly observable coloring.", "In such a case white light penetrating from the back surface also tends strongly to wash out any net coloration since almost all of the white light incident on the back surface will emerge from the front as white light, raising the background level to approximately 100%.", "It should be noted that in this case, if R 1 and R 2 are in phase, R 3 will be out of phase;", "i.e. will destructively interfere with R 1 and R 2 because of the additional ±π phase change at the second reflection at the glass-plastic interface.", "The additional path length in the glass is, of course, an integral number of wavelengths since that is the condition for the first internally reflected ray R 2 to be in phase with R 1 .", "The third internally reflected ray R 4 is in phase, and the fourth R 5 out of phase etc.", "This factor is unimportant for the case shown in FIG. 4 because of the small reflectivities and intensities involved, but is important in the new elements involved in the present invention.", "Next consider a simple highly polished opaque reflecting metal layer 7 as in FIG. 5(a) (e.g. vacuum deposited Al on glass) with a reflectivity assumed for discussion to be 90% (normally higher) and flat across the visible spectrum.", "The reflectivity for such an opaque absorbing medium with light incident from a dielectric of index of refraction n o is given by: ##EQU8## where n m ≡index of refraction of metal k m ≡extinction coefficient for metal which reduces to ##EQU9## For some metals such as Al where the relative values of n m and k m are appropriate across the spectrum (visible) the reflectivity remains fairly flat and the reflected light has a neutral gray pure metallic appearance.", "For other metals such as Cu, the relative values of n m and k m are such that R varies across the visible spectrum (e.g. for evaporated Cu, R≈58% at 4,500 Å and R≈96% at 7,000 Å).", "For the example given, the Cu therefore appears by reflected light to be reddish since more of the red end of the spectrum is reflected.", "As discussed later, this factor is also used in controlling coloration using the present invention.", "Returning to FIG. 5(a) the situation is quite simple with only those rays reflected from the first surface being viewed by the observer (i.e. a simple front surface mirror).", "If, however, the metal is covered by a thin layer (such as that shown at 8 in FIG. 5(b)) of glass, or other appropriate medium, the situation changes to that shown in FIG. 5(b) where again the "initial"", "reflected ray is only 3.5% of the incident energy.", "A phase change of ±π is assumed at the glass-metal interface.", "In a more rigorous treatment the phase change ρ is given by: ##EQU10## where the symbols have the meanings previously given.", "For many glass-metal combinations ρ is near π, while for others it can vary by significant factors.", "This divergence from an exact π phase change on reflection has little effect on the present invention since its effect is to slightly shift the value of the thickness t required for constructive or destructive interference at a given wavelength, through the addition of an error factor viz.", "(for constructive interference) ##EQU11## In practising the invention, as discussed below, one simply adjusts t to compensate for the Δt p error (if significant).", "A similar correction exists for variations in reflectivity but is of no consequence to the present invention since it is basically an angle of incidence correction to reflectivity and we are primarily concerned with normal incidence.", "As shown by equation (1) and similar formulae, constructive and destructive interference coloring effects will be apparent at non-normal angles of incidence which will vary from those at normal incidence, but this has no effect on the practice of the invention.", "Referring to FIG. 5 (b), for phase change of ±π, the first internally reflected ray R 2 is in phase with R 1 at λ c given by equation (5) and has an intensity of (100-3.5)%×90%×(100-3.5)%=96.5%×90%×96.5%=83.81% of the original intensity.", "R 3 is out of phase with R 1 and R 2 and has an intensity of 96.5%×90%×3.5%×90%×96.5%=2.64%.", "R 4 is in phase with an intensity of 96.5%×90%×3.5%×90%×3.5%×90%×96.5%=0.083%.", "The sum of R 1 , R 2 , R 3 and R 4 (ignoring higher components) is therefore 3.5+83.81-2.64+0.083=84.75% One cannot readily state what the reflected amplitudes are for wavelengths other than the coherent value since they depend critically on wavelength, materials etc.", "However, in general, considering R 2 as the primary ray because of its intensity, (R 1 +R 4 ) and R 3 will tend to cancel because of the corresponding phase differences so that the intensity variation cannot be greater than approximately 83.81±[(3.50+0.083)-2.64]=84.75 to 82.87 As a rough approximation, the maximum differential effect is given by the value for λ c minus the lowest value above, i.e. I c =84.75, I B =82.87 and ##EQU12## A special case can occur if the thickness t is such (see later discussion) that destructive interference at λ D can occur simultaneously with constructive interference at λ c .", "Should such occur, R 2 , R 3 and R 4 for λ D are all in phase with each other and out of phase with R 1 since each additional internal reflection traversal adds 2π to the phase (additional half wavelength due to path length plus π phase change at glass-metal interface).", "The amplitude for this value of λ D is given by (83.81+2.64+0.083)-3.5=83.03% which gives less than the maximum differential effect calculated above for "random"", "wavelengths.", "Interference colors on such highly reflecting metal surfaces therefore tend to be weak or washed out to the eye because of the small differential intensities involved.", "With the foregoing as background, the operation of the present invention may be readily understood.", "Consider the situation shown in FIG. 6(a) where the arrangement is the same as that in FIG. 5 (b) except that the metal layer 9 is only 20% reflecting (again assumed flat across the visible spectrum).", "For a thickness t corresponding to constructive interference at λ c , the intensities and phases of the reflected rays are R 1 =3.5% (initial), R 2 =18.62% (constructive), R 3 =0.13% (destructive) with the higher orders being insignificant.", "The total reflected intensity at λ c is therefore 3.5+18.62-0.13=22% In general, for other "normal"", "wavelengths the effects of R 1 and R 3 may be approximated (considering R 2 as the main reflected ray) by assuming that they will add half their difference in intensity to R 2 (i.e. 1/2(3.5-0.13)=1.69%) so that the total intensity R 1 +R 2 +R 3 may be estimated as 18.62+1.69=20.31.", "The differential effect for λ c above these wavelengths is therefore ##EQU13## compared to the -2.2% found for the opaque reflecting metal case shown in FIG. 5(b).", "More importantly, if a simultaneous destructive interference occurs at λ D at the same value of t, the minimum amplitude is given by (R 2 +R 3 )-R 1 or (18.62+0.13)-3.50=15.25% In this case the differential effect ##EQU14## or 44% above background which is roughly 20 times that found for the opaque reflecting metal (90%) situation in FIG. 5(b).", "For comparison, FIG. 6(b) shows the values for a 30% reflecting layer 10.", "In this case the intensity at λ c is given by (R 1 +R 2 )-R 3 .", "Since R 1 =3.5%, R 2 =96.5%×30%×96.5%=27.94% and R 3 =96.5%×30%×3.5%×30%×96.5%=0.29%, then the intensity is 3.50+27.94-0.29=31.15% at λ c ;", "27.94+1/2(3.5-0.29)=29.54% for an average noncoherent λ A ;", "and (27.94+0.29)-3.50=24.75% for a destructively interfering λ D .", "The differential effects are therefore ##EQU15## These are considerably smaller than for the 20% reflecting layer case but are still much larger than the ≈2.2% found for the 90% reflecting case or for the simple glass on plastic case.", "One of the basic elements of this invention is therefore the adjustment of the thickness of the dielectric medium (glass in examples) used as an interference layer, and the reflectivity of the semi-reflecting metal layer to enhance and/or optimize the differential coloring effect.", "If one goes to reflectivities less than 20% the effect is enhanced still more, with, for example, the differential effect (both λ c and λ D occurring simultaneously) being >100 at 10% reflectivity.", "At higher reflectivities than 30%, the effect, of course, decreases in intensity.", "In examples given, SiO 2 (n=1.46) has been used as the interference dielectric since this material has been extensively used in demonstrating the invention.", "The differential effect can be increased still further, however, by using other dielectrics having higher values of n, thereby affecting the reflectivities (particularly at the front surface) and ultimately the differential effect.", "Consider FIG. 7 which gives the situation comparable to that shown in FIG. 6(a) (20% reflecting metal) but with TiO 2 having n=2.60 replacing the SiO 2 as the interference medium.", "In such a case R 1 =19.753% by equation (3), R 2 =80.247%×20%×80.247%=12.8792%, and R 3 =80.247%×20%×19.753%×20%×80.247%=0.5088%.", "Considering only R 1 , R 2 and R 3 the enhanced intensity I c =(R 1 +R 2 )-R 3 =(19.753+12.8792)-0.5088=32.1234 and the background intensity I B =R 1 -(R 2 +R 3 )=19.753-(12.8792+0.5088)=6.3650.", "The maximum differential effect is given by ##EQU16## which is nearly a factor of 10 greater than in the 20% reflecting SiO 2 dielectric case.", "One could therefore reduce the reflectivity of the metal even more to allow much more of the light to penetrate to the inside while still maintaining a very strong coloring effect.", "(The limiting factor will be the increased reflectivity at the glass plastic interface as the metal is made less dense and the relative index of the glass and plastic becomes larger leading to increased reflectivity.", "Exact values depend on a given application and materials).", "The maximum effects, of course, exist when the sum of R 1 and R 2 is much greater than their difference as in the above TiO 2 case.", "In general, this occurs when the index of refraction of the dielectric has a relatively (compared to SiO 2 ) high value.", "Another example is Si 3 N 4 which has n=2.03 resulting in a maximum differential effect of 503%.", "Other materials such as SiO (n=1.95) and Al 2 O 3 (n=1.76) will have coloring effects which are more pronounced than those of SiO 2 and others will be apparent to those skilled in the art.", "The choice of material depends on the particular application.", "In the discussions which follow, the SiO 2 situation is the one which is considered in all cases.", "For the non-opaque, semi-reflecting metal cases, white light incident upon and penetrating through the rear surface and emerging through the front tends to decrease the effect.", "The major decrease is due to an increase in the background level since interference effects that occur in the thin glass layer (i.e. interference effects between light reflected at plastic-metal interface and that reflected at glass-air interface) will be non-coherent with those occurring due to light incident on the front and even if occurring will have a much smaller effect due to the much higher background.", "The latter results because the transmitted light differential effect is the complement of the reflected light effect and is superimposed on a much higher background (80% of light reaching plastic-metal interface minus 3.5% reflected at glass-air interface).", "Considering only the increase in background, if white light of intensity 100% of I(intensity of white light on front surface) is incident on the rear surface in the 20% reflectivity (metal) case, approximately 74.5% (after three reflective losses at various interfaces) will exit through the front surface.", "The effect in the maximum differential case (λ c +λ D simultaneously) is a reduction from 44% to a value of ##EQU17## Although in a practical embodiment of the invention (e.g. use as sunglasses) there is much less than 100% of I coming through the rear surface, even in the worst case of 100% of I the differential effect is much greater than that obtained (˜2.2%) for a 90% reflecting layer case.", "This negative effect of white light penetrating through the rear surface can be partly negated by having the substrate (plastic in example) made of visible light absorbing material.", "If, for example, the plastic in the 20% reflecting case were of a thickness and absorptivity A to be 50% absorbing in the visible, white light of intensity I entering through the rear surface would have an intensity of 0.371(1×0.965×0.5×0.8×0.965) on exiting through the front surface and the maximum differential effect (λ c +λ D simultaneously) would be ##EQU18## In the real case of sunglass use, the light entering through the rear is much less, say 20% of I maximum, being only that going around the frames and reflected off the skin.", "For this value the maximum differential effect equals approximately 22% for the non-absorbing substrate use and 29.8% for the 50% absorbing substrate case.", "Since the thickness t of the interference medium (glass in example), the reflectivity R of the reflecting metal;", "the absorptivity A of the substrate material and the ratios thereof are infinitely variable, within the limits of minimal reflectivity (no metal) and no absorption (clear substrates) and maximum reflection (opaque polished or evaporated metal) and maximum absorption (highly absorbing substrate), the color and/or intensity of the structure as viewed by an observer on the front or incident surface and that of the light reaching a viewer behind the rear surface (wearer for sunglasses) can be varied over an extremely broad range.", "In the practical embodiment of the invention, this allows the user to reduce the light reaching the inside viewer to a desirable level, e.g. 30% of neutral or near neutral shading for a sunglass wearer, while obtaining the desired color and intensity level for an external viewer.", "It has been demonstrated in practising the invention that neutral shading can be obtained by having a substrate having neutral absorption at the proper level.", "This can be used to overcome or wash out coloring effects due to light coming from the front surface (non-reflected) which is the complement of that reflected and is therefore colored, although of much less effective density than the reflected component because of the much higher background (˜74% of light being transmitted in 20% reflecting and non-absorbing substrate case).", "The light reaching the inside receiver can also, of course, be colored if desired.", "A, R and t etc.", "may be adjusted to yield other values of external coloring and intensity etc.", "for other purposes, e.g. for office windows.", "For this use, in one test of the invention the absorbing substrates were of glasses manufactured by PPG Industries, Inc. under the names solarbronze, solargray and solarex.", "The metal layer reflectivity was adjusted to reduce the light level penetrating to the inside to a comfortable level while maintaining the neutral characteristics (particularly for solarbronze or solargray) and changing the color as viewed from the outside to that desired but for this purpose deliberately of less intensity than in the normal sunglass case.", "However, it should be noted that all ranges of values for external color intensity and transmitted light intensity may be used for any and all applications.", "Of course, in a limited number of embodiments of the invention (such as wall panels, etc.) the transmitted light intensity may be of no consequence.", "A very important factor that is observed in the practical embodiment of the invention is that the colors so formed have an extremely metallic appearance;", "i.e. a metallic nature similar to that obtained with a highly polished metal reflector such as Al, but with deep color shading resulting in a striking "colored metallic"", "appearance.", "This occurs because the differential effect primarily results from reflection at a very thin layer in the same way that reflection results at the surface of a neutral metal reflector.", "The resulting radiation is therefore space as well as time coherent and the eye perceives that the light emanates from a restricted layer or layers.", "(This is in contrast, for example, to absorbing glasses which have a color due to absorption and reemission of radiation at many spatially separated atomic layers in the glass and which therefore do not have a metallic appearance).", "This factor when optimized by proper use of the present invention gives a recognizable and distinctive appearance when A, R and t etc.", "are chosen for vivid coloring.", "The practice of the invention can best be understood and mastered by a full appreciation of the effect of using a partially-reflecting metal layer as discussed previously in conjunction with Table I which gives the colors observed by previous investigators (Pliskin and Conrad-IBM Journal, January 1964) for thermally grown films of SiO 2 on polished (i.e. opaque maximum reflecting) slices of silicon.", "The latter is the case normally observed previously, where the coloration is not enhanced nor has a strong metallic appearance as in the present invention.", "Similar, but not exactly the same, colors were observed in the practical demonstrations of the present invention.", "Exact coloring depends on the metal used as the reflecting layer and varies in each case.", "Table I has been prepared specifically for this invention to explain the colors obtained and to show detailed operation.", "It gives the calculated wavelengths for constructive interference ##EQU19## and destructive interference ##EQU20## in association with the colors observed by Pliskin and Conrad.", "Note that the value of t given is the real value, not the optical thickness tn g and the λ c 's and λ D 's having effects in the visible are outlined.", "At 500 Å, there is no visible wavelength λ c or λ D at which interference effects should occur if the glass (SiO 2 ) has an index of refraction of ˜1.46 (used for calculating Table 1).", "The tan color observed by Pliskin and Conrad can be explained by the following considerations.", "If the SiO 2 is oxygen deficient and has an appreciable proportion of SiO having an index of refraction of 1.95 (or other oxygen-deficient SiO x compounds) as can occur at the interface for thin thermally grown SiO 2 layers on Si, the λ D for destructive interference (m=o) is 3,900 Å which is above the edge for optical interference (˜3,800 Å) in the visible.", "Some of the violet component will be removed from the reflected light under these conditions, so that the remaining reflected light has a tan appearance or color as observed by Pliskin and Conrad.", "However, for n=1.46 which is obtained if the silicon is deposited by ion beam sputtering or ion beam implantation sputtering techniques, no tan color is apparent when layers of 500 Å thickness are deposited on highly reflective metal layers such as opaque ion beam sputtered Al on smooth glass or plastic substrates.", "Such layers, if hermetic as in the ion beam sputtering case, can be used to protect the reflecting metal against corrosion etc.", "without altering its optical characteristics at wavelengths longer than ˜3,000 Å.", "This has been clearly demonstrated for the present invention.", "If the thickness is increased to 700 Å, λ D becomes 4,088 Å, moving the removed (i.e. destructively interfered) component farther towards the blue, producing a brown appearance.", "At 1,000 Å, λ D is 5,840 Å which is in the yellow part or middle of the spectrum.", "Both ends of the spectrum therefore show up in the reflected light which is dark violet to red-violet.", "At t=1,200 Å the red end of the spectrum is removed and the reflected light centers around the blue region.", "These results are confirmed by Pliskin and Conrad's observations, and one can assume that for these thicker layers the problem of oxygen deficiency at the interface is relatively less severe.", "At approximately 1,300 Å thick, a new effect occurs;", "i.e. "constructive"", "interference at 3,800 Å with the first corresponding value in the table being a λ c of 4,380 Å for t=1,500 Å.", "For this value of t, the coloring is primarily due to constructive interference rather than destructive effects so the reflected light has a color (light blue) dominated by λ c .", "In fact the royal blue observed at 1,200 Å probably has a constructive component in the deep violet due to the spread around λ c (see FIG. 3(b)) and the extension of enhancement effects to higher and lower values of λ than the precise value λ c .", "In addition, because of the spatial as well as time coherent nature of the reflected light, it assumes a metallic appearance which is also observed at t=1,700 Å and 2,000 Å.", "However, these effects for opaque maximum reflecting substrates as in the Pliskin and Conrad case are very small and disappear at larger values of t, but are very prominent and continue throughout the large values of t if the present invention is practised to produce large differential effects as discussed previously.", "Also beginning at t=2,000 Å is a definite simultaneous occurrence of λ c and λ D .", "At t=2,200, λ c =6,424 Å while λ D =4,283 Å so the reflected light is enhanced around λ c and has a decreased value around λ D , the resulting color being a combination of the two effects, or gold with slight yellow orange for this example.", "Using the present invention, the enhancement of the color through the differential effect plus the spatially coherent nature of the reflected light results in a "strong"", "metallic appearance for all colors corresponding to thicknesses greater than 1,300 Å.", "This metallic appearance and strong coloration continue until the thickness is such that there are so many interference effects occuring simultaneously at different λ c 's and λ D 's (i.e. for different values of m-see Table 1) that the resulting reflected light again tends to white (e.g. in Table 1, for t=15, 400 Å, there are 6 λ c 's corresponding to m=6, 7, 8, 9, 10 &", "11 and 6 λ D 's corresponding to m=6, 7, 8, 9, 10 and 11).", "Above >15,000 Å the interference colors become hard to observe on opaque maximum reflecting substrates although still easily observed on the partially-reflecting substrates of the present invention because of the color enhancement.", "From Table 1, one can also see that for the values of t which would be used in practising the invention, there are values of λ c and λ D corresponding to effects in the IR (infrared) and UV (ultraviolet) regions of the spectrum.", "Such effects are discussed below in connection with an important variation on the invention.", "Table 1 allows the user to choose the correct values of t to practise and optimize the effects of the present invention when used in conjunction with appropriate reflectivity calculations.", "No precise format can be given for the latter since it depends on factors (e.g. light levels, color density, means of depositing materials etc.) which must be chosen for a given application.", "The most enhanced colorations are obtained for one or two orders of λ c combined with one or two orders of λ D which in general applies for t between 1,500 Å and 6,000 Å.", "This is not rigid, since the coloration depends on other factors such as reflectivity, absorption in the substrate, type of reflecting metal etc.", "but serves as a guideline for easiest practice of the invention.", "SiO 2 layers of this thickness are also found to supply adequate chemical and mechanical protection for the underlying metal and/or plastic in many applications (e.g. sunglasses or windows).", "Another variation which can be used to extend the range of colors obtained by the present invention is to use an absorbing dielectric medium for the interference dielectric, on the front surface.", "The color thus obtained is a combination of the interference effect and the absorption and reemission effects in the interference dielectric.", "It should also be noted that light penetrating from the rear through an absorbing substrate will affect the coloring to an extent depending on the intensity of the rear light and the color of the absorbing substrate.", "The latter may be used to modify the color or to "mute"", "the metallic effect in applications such as office building windows.", "Another variation is to choose the partially-reflecting metal from those that do not have near constant reflectivity across the visible spectrum but which have varying R. An example is copper which has a reflectivity of ˜58% at 4,500Å and ˜97% at 7,000Å.", "This difference in reflectivity can be used further to enhance certain colors, e.g. red tones, because of their obvious enhancement of the differential effect due to the difference in reflectivity.", "Gold, nickel, and brass are other examples of such metals or alloys.", "Others will be obvious to those skilled in the art.", "A most important variation of the invention is obtained by extending its application to other wavelengths outside of the visible, in particular into the infrared (IR) region.", "This is of special importance for windows designed to reduce or control the amount of radiant heat (from sun, atmosphere, or other hot sources such as other buildings etc.) entering the building in order to conserve energy by reducing the air conditioning load.", "In order to optimize this saving, it is desirable that any optical layers used to reflect or reject the incident IR radiation be on the outside surface of the window.", "If applied to the inside, much of the incident IR radiation will be absorbed in the glass itself, either on the first pass through or on the second pass after reflection, thereby heating up the glass.", "Much of this heat in the glass is then transferred into the interior of the building by convection currents of the internal air or by reradiation at longer λ's.", "Applied to the outside, such reflecting layers are therefore more effective in summer but are still effective in preventing heat losses in winter since the IR energy radiated by internal objects will either be absorbed in the glass, and partially returned to the room by convection etc.", ", or for the portion that passes through the glass to the metal layer, will be reflected back and absorbed in the glass or returned to the room.", "With the present invention, this control of the IR radiation entering or leaving the inside of the building can be effected while still controlling the visible light entering the building and also the external and internal coloring effects.", "This capability results from the longer wavelengths of the IR radiation.", "By reducing the thickness of the partially reflecting metal layer, one can control the amount of visible light entering the building for lighting needs (e.g.≈50% of incident light for R≈20% and 40% absorbing substrate), while achieving the condition for optimizing color effects as discussed previously, and maintaining a high IR reflectivity.", "In demonstrating this invention, it has been demonstrated that this combination can be achieved if the partially-reflecting metal is one of inherently high IR reflectivity which is put down by a technique or process (such as ion beam sputtering) which provides uniform dispersion of the metal without appreciable agglomeration.", "At thicknesses where the layer looks relatively open to visible λ's, the same partially-reflecting layer looks relatively opaque to the IR λ's since their size is such that they intercept more of the metal atoms on the average, leading to increased reflection.", "In practice, visible reflectivities have been reduced to the 20-50% range in the visible, while maintaining the IR reflectivity at >70% and as high as 95% in the near (e.g. 2.5μ) and far IR (e.g. >10μ).", "An important region for control of heat load on buildings is below 2.5μ for air conditioning requirements (most of heat incident from outside) since the terrestrial solar spectrum is such that approximately half of the sun's radiation is in the visible and half in the near IR (below 2.5μ).", "However, the buildings also receive longer wavelength (4-100 microns with maximum intensity near 10 microns) radiation from the atmosphere which also exerts a heat load.", "For winter conditions, where one wants to prevent radiation of heat from internal bodies with temperatures of ˜25°-30° C., the far IR characterized is important since the peak of the black body radiation spectrum for a body at 28° C. is approximately at 10μ.", "It is therefore desirable that the reflectivity be high across the IR spectrum.", "This has been demonstrated with the present invention using Cu or brass as the reflecting metal, both of which have higher reflectivity at the longer visible λ's than at the shorter end of the spectrum.", "The value of reflectivity can thus be adjusted to give relatively high IR reflectivity, including the region from 8,000 Å up to 2.5μ (25,000 Å) while keeping the average visible light reflectivity low.", "Other materials such as Au and Ag etc.", "may be used to achieve the desired function but are relatively expensive and for many application methods difficult to deal with.", "As evident from Table 1 and discussed previously, interference effects also occur in the IR as well as in the visible for interference layers of interest for coloring effects.", "These interference effects in the IR are, however, of much less importance since the IR reflectivity is high (for properly chosen metal layer) with or without interference effects, and differential effects are relatively unimportant.", "In demonstrating the present invention, ion beam sputtering and ion beam implantation sputtering have been used.", "However, any process that is capable of putting down the necessary materials in the necessary form may be used without affecting the operation of the invention.", "The deposition technique used in demonstrating the invention can also put down materials such as Au or Ag on both glass and/or plastic as well as other materials without intermediate or bonding layers, as required with many other techniques (e.g. evaporation).", "This is important in achieving the correct degree of reflectivity for proper operation of the invention.", "More importantly, it is of utmost necessity that the glass interference layer over the metal layer protect the metal layer from chemical (environmental) and mechancial (cleaning etc.) attack as well as providing the necessary interference function.", "This is only possible if the glass is impervious to chemical vapors or liquids in very thin layers, is mechanically hard and is of optical quality.", "Ion beam sputtered fused SiO 2 has been used to demonstrate the invention since it meets all of these requirements because of its unique characteristics.", "However, any other method of applying the interference glass with the necessary characteristics will result in successful operation of the invention.", "It is important that the glass layer be applied immediately over the metal layer and in such a manner that the metal does not oxidize or otherwise alter its reflecting state.", "If, for example, the metal is a freshly deposited layer of Cu, and it is exposed to air or O 2 for an appreciable time before the hermetic interference layer (or equivalent) is applied, the Cu will oxidize and the reflectivity will decrease, affecting the visible coloration, reflected and transmitted light intensities and IR rejection capability.", "If the glass is not hermetic, the characteristics of the structure will degrade with time.", "Au is not subject to severe degradation but is relatively expensive and for some application techniques difficult to apply.", "Application of the hermetic seal immediately over the reflecting layer can be used to provide very thin (500 Å or less) non-colored protective layers if the applied glass is impervious to chemical attack in thin layers.", "As discussed previously, the coloration observed by Pliskin and Conrad at 500 Å may be due to inadequate characteristics of the glass layer.", "The use of such thin layers avoids the expense of applying thick layers (>2μ) to eliminate interference color effects.", "This innovation has been demonstrated and is of importance for protecting front surface mirrors while maintaining optical characteristics, for applications such as optical instrument mirrors and concentrators for energy conservation and generation systems, for hermetically sealing solar cells for terrestrial applications etc.", "Another variation of the present invention is its use on plastic substrates, both absorbing and non-absorbing at visible λ's, to provide IR rejection.", "Whereas glass substrates, in many practical areas of interest such as sunglasses, absorb some of the incident IR, plastics in general do not.", "Thus wearers of plastic sunglasses are subjected to IR heating of the eye, leading to drying out of the membranes and irritation, even if the glasses are adequate for visible radiation purposes.", "The present invention avoids this effect through rejection of undesirable IR radiation while controlling visible light and coloring effects at desirable levels.", "With the metal applied as a thicker highly reflecting opaque layer, "plastics"", "can also be used as excellent visible plus IR mirrors and concentrators etc.", "for solar energy generation and conservation systems, with the metal layer protected by a thin (˜500 Å) hermetic and mechanical seal as discussed previously.", "These effects have been demonstrated.", "Still another variation of the invention is its use to produce coloring effects in wall panels, etc.", "without regard to transmission properties.", "Having thus described the principles of the invention, together with several illustrative embodiments thereof, it is to be understood that, although specific terms are employed, they are used in a generic and descriptive sense and not for purposes of limitation, the scope of the invention being set forth in the following claims.", "TABLE 1__________________________________________________________________________Color__________________________________________________________________________Tan 500Brown 700Dark Violet to Red-Violet 1,000Royal Blue 1,200Light Blue to Metallic Blue 1,500Metallic to very light Yellow-Green 1,700Light Gold on Yellow - slightly metallic 2,000Gold with slight yellow-orange 2,200Orange to Melon 2,500Red-Violet 2,700Blue to Violet-Blue 3,000Blue 3,100Blue to Blue-Green 3,200Light Green 3,400Green to Yellow-Green 3,500Yellow-Green 3,600Green-Yellow 3,700Yellow 3,900Light Orange 4,100Carnation Pink 4,200Violet-Red 4,400Red-Violet 4,600Violet 4,700Blue-Violet 4,800Blue 4,900Blue-Green 5,000Green (broad) 5,200Yellow-Green 5,400Green-Yellow 5,600Yellow to "Yellowish"", "5,700Light Orange on Yellow to Pink borderline 5,800Carnation Pink 6,000Violet-Red 6,300Bluish (borderline violet to bluegreen - appears greyish) 6,800Blue-Green to Green (quite broad) 7,200"Yellowish"", "7,700Orange (rather broad for Orange) 8,000Salmon 8,200Dull, light red-violet 8,500Violet 8,600Blue-Violet 8,700Blue 8,900Blue-Green 9,200Dull Yellow-Green 9,500Yellow to "Yellowish"", "9,700Orange 9,900Carnation Pink 10,000Violet-Red 10,200Red-Violet 10,500Violet 10,600Blue-Violet 10,700Green 11,000Yellow-Green 11,100Green 11,200Violet 11,800Red-Violet 11,900Violet-Red 12,100Carnation Pink to Salmon 12,400Orange 12,500"Yellowish"", "12,800SkyBlue to Green-Blue 13,200Orange 14,000Violet 14,500Blue-Violet 14,600Blue 15,000Dull Yellow-Green 15,400__________________________________________________________________________λ.", "sub.", "ct (A)m = 1234567891011__________________________________________________________________________ ##STR1## ##STR2## ##STR3## ##STR4## ##STR5## ##STR6## ##STR7##__________________________________________________________________________λ.", "sub.", "Dt (Å)m = 01234567891011__________________________________________________________________________ ##STR8## ##STR9## ##STR10## ##STR11## ##STR12## ##STR13## ##STR14##__________________________________________________________________________" ]
This is a divisional application of Ser. No. 08/309,341, filed Sep. 20, 1994, now U.S. Pat. No. 5,594,119, the contents of which are incorporated herein by reference in their entirety. FIELD OF THE INVENTION The present invention relates to a gene encoding a fungal vacuolar protease. In particular, the invention relates to a carboxypeptidase gene of a filamentous ascomycete or deuteromycete fungus, such as those of the genus Aspergillus. BACKGROUND OF THE INVENTION The fungal vacuole is an acidic organelle that contains many hydrolases, including several proteases, and is essentially equivalent to the mammalian lysosome. Several of the hydrolases have been identified and characterized in one or more species of fungi, particularly in yeast; these include protease A (PEP4 or PrA), protease B (PrB), aminopeptidase (APE), dipeptidyl aminopeptidase B (DPAP B), carboxypeptidase Y (CPY), and carboxypeptidase S (CPS). Most of the vacuolar hydrolases are glycoproteins which are synthesized as inactive precursors. In fact, all the aforementioned proteases with the exception of APE have signal peptides that lead to transit through the secretory pathway. In the late golgi, vacuolar proteins are sorted from secretory proteins and eventually delivered to the vacuole. In addition to a signal peptide, most vacuolar proteins also have a propeptide which is cleaved upon delivery to the vacuole to generate the mature active enzyme. It has been demonstrated that the amino acid information in PrA and CPY required for vacuolar targeting is present within the propeptide (Johnson et al., Cell 48: 875-885, 1987; Rothman et al. PNAS USA 83: 3248-3252, 1989; Valls et al., Cell 48: 887-897, 1989; Valls et al. J. Cell Biol. 111: 361-368, 1987). For CPY a string of four amino acid residues (QRPL) has been shown to be required for localization to the vacuole (Valls et al., J. Cell Biol. 111: 361-368, 1990). Once delivered to the vacuole, proteinase A (pep4) cleaves the propeptide of CPY and PrB leading to the activation of the proteases (Ammerer et al., Mol. Cell. Biol. 6: 2490-2499, 1986; Woolford et al., Mol. Cell. Biol. 6: 2500-2510, 1986). In S. cerevisiae, three classes of mutants which mislocalize or missort vacuolar proteins have been identified (Bankaitis et al., PNAS USA 83: 9075-9079, 1986; Robinson et al., Mol. Cell. Biol., 8: 4936-4948, 1988; Rothman et al., EMBO J. 8: 2057-2065, 1989; Rothman and Stevens, Cell 47: 1041-1051, 1986). These mutants are called rids or vacuolar protein sorting mutants. Several of these mutants are isolated using a selection based on the observation that overexpression of a vacuolar protease due to a high copy number on a plasmid leads to a secretion of vacuolar proteases (Stevens et al., J. Cell Biol. 102: 1551-1557, 1986; Rothman et al, PNAS USA 83: 3248-3242, 1986). This suggests that it is possible to saturate the sorting machinery within the late golgi. In S. cerevisiae, it has also been demonstrated that strains deleted for PEP4, CPY and PrB produce higher levels of heterologous proteins due to a decrease in proteolysis of the desired product. Therefore, the vacuolar proteases in question are important from a commercial point of view because many of the fungi which produce them are used for recombinant production of heterologous proteins. The presence of these proteases in fermentation is undesirable, in that they can degrade the protein of interest, thereby significantly reducing yield. Elimination of the function of any given protease is facilitated by the disruption or deletion of the gene encoding it; however, doing so first requires identification and isolation of the corresponding gene in the host species of interest. As noted above, a few such genes have been isolated from various yeast strains; however, the genes encoding vacuolar proteases in the filamentous ascomycetes or deuteromycetes are less well known. For example, PEPC (Frederick et al., Gene 125: 57-64, 1993) and PEPE (Jarai et al., Gene 145: 171-178, 1994) genes coding for two other vacuolar proteases from Aspergilus niger have been isolated. PEPC codes for a proteinase B(PrB) homologue, and PEPE codes for a proteinase A homologue. The gene PEP4 from Neurospora crassa coding for a PrA homologue has also been cloned (Bowman, 17th Fungal Genetics Conference, 1993). For the first time herein is described the gene encoding a vacuolar CPY from a filamentous ascomycete or deuteromycete. SUMMARY OF THE INVENTION The present invention relates to a nucleic acid construct comprising a sequence encoding a filamentous ascomycete or deuteromycete carboxypeptidase Y, as well as the recombinantly produced protein encoded thereby. As used herein, "nucleic acid construct" is intended to indicate any nucleic acid molecule of cDNA, genomic DNA, synthetic DNA or RNA origin. The term "construct" is intended to indicated a nucleic acid segment which may be single-or double-stranded, and which may be isolated in complete or partial form from a naturally occurring gene or which has been modified to contain segments of DNA which are combined and juxtaposed in a manner which would not otherwise exist in nature. The construct may optionally contain other nucleic acid segments. In a preferred embodiment, the sequence encodes a carboxypeptidase of the genus Aspergillus. The invention also provides a method for producing a non-carboxypeptidase-producing filamentous ascomycete or deuteromycete cell, which comprises disrupting or deleting the carboxypeptidase gene so as to prevent the expression of a functional enzyme, or treating the gene by classical mutagenesis using physical or chemical treatments to generate cells which are reduced or lacking in their ability to produce CPY. In addition, the invention also encompasses a filamentous ascomycete or deuteromycete which is unable to produce a functional carboxypeptidase enzyme, or which produces the carboxypeptidase in reduced amounts relative to the amount produced by the wild-type strain. Such organisms provide the basis for an improved method of recombinant protein production, wherein the carboxypeptidase-deficient microorganism is transformed with the nucleic acid construct encoding the protein of interest, and cultured under conditions conducive to the expression of the protein. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 illustrates the DNA sequence and translation of the A. niger Bo-1 genomic CPY clone. FIG. 2 illustrates the DNA sequence and translation of A. niger SFAG 2 CPY cDNA. The predicted site for signal peptidase cleavage and the N-terminus of mature CPY are indicated. FIG. 3 illustrates the construct used in disruption CPY. DETAILED DESCRIPTION OF THE INVENTION Attempts to isolate an Aspergillus carboxypeptidase Y are initiated by designing a series of degenerate oligonucleotides, using the sequences of S. cerevisiae CPY, Penicillium janthinellum carboxypeptidase S1 (Svedsen et al., FEBS 333: 39-43, 1993, and malt carboxypeptidase-MIII (S.o slashed.rensen et al., Carlsberg Res. Commun. 54: 193-202, 1993). The oligonucleotide sequences are provided the examples below. These sequences are used as primers in various combinations in a PCR reaction using Aspergillus niger strain Bo-1 genomic DNA as a template. Two of the reactions (with primers 1-1 and 2-1; and 1-2 and 2-2) yield an 1100 bp amplification product, which is subcloned and sequenced, but none of the subclones has significant homology to CPY to be identified as the gene of interest. Further PCR reactions with primers 3-1, 3-2, 4-1, 4-2, 2-1 and 2-2 are then made. In two of the reactions (primers 4-1 and 2-1; and 4-2 and 2-1) a 600 bp amplification product is obtained. This product is subcloned and 11 of the subclones sequenced; nine of these subclones are identical, and have homology to carboxypeptidaseY genes from other sources. The insert from one of the subclones is used to probe A. niger genomic DNA; hybridization with single bands is observed with BamHI. HindIII, and SalI digests, suggesting that a single CPY gene exists in A. niger. Hybridizations are done at 65° C. in 1.5×SSPE, 1.0% SDS, 0.5% non-fat milk and 200 μg/ml salmon sperm DNA. An A. niger genomic DNA bank in EMBL4 is prepared and probed with the PCR CPY-derived gene fragment ( 32 P-labeled), in order to isolate a full length gene. Out of approximately 28,000 plaques, 11 positives are picked; nine of these still hybridize with the probe after purification. A 5.5 HindIII fragment common to a majority of these clones is identified as the A. niger CPY gene. This fragment is subcloned and sequenced; the sequence of the fragment, including the CPY coding region and predicted amino acid sequence, is provided in FIG. 1. Subsequently, a cDNA bank from a different A. niger strain is also screened. At least one full-length clone is identified from this library as well. This clone is sequenced and the sequence is depicted in FIG. 2. Both DNA sequences predict a CPY precursor of 557 amino acids in length. Based on a comparison with the homologous gene from S. cerevisiae, CPY from A. niger appears to have a pre-propeptide of 137 or 138 amino acids. The gene contains one intron of 61 base pairs. A comparison of the two A. niger sequences will show some difference in amino acid sequence, which presumably reflects the different strains from which the genomic and cDNA clones are isolated. A comparison with the amino acid sequences of the corresponding CPY genes of S. cerevisiae and C. albicans shows a 65% and 66% identity, respectively. The present invention is not limited to the use of the sequences disclosed in FIGS. 1 and 2. First, the invention also encompasses nucleotide sequences which produce the same amino acid sequence as depicted in FIG. 1 or 2, but differ by virtue of the degeneracy of the genetic code. In addition, the difference in amino acid sequence shown for two strains of the same species shows that variation within the sequence of a single species is tolerated, and using the techniques described herein, such variants can readily be identified. Therefore, when "A. niger" is referred to in this context, it will be understood to encompass all such variations. In particular, the invention also encompasses any variant nucleotide sequence, and the protein encoded thereby, which protein retains at least about an 80%, preferably about 85%, and most preferably at least about 90-95% homology with the amino acid sequence depicted in FIG. 1 or 2, and which qualitatively retains the activity of the sequence described herein. Useful variants within the categories defined above include, for example, ones in which conservative amino acid substitutions have been made, which substitutions do not significantly affect the activity of the protein. By conservative substitution is meant that amino acids of the same class may be substituted by any other of that class. For example, the nonpolar aliphatic residues Ala, Val, Leu, and Ile may be interchanged, as may be the basic residues Lys and Arg, or the acidic residues Asp and Glu. Similarly, Ser and Thr are conservative substitutions for each other, as are Asn and Gln. In addition, the isolated gene provides a means for isolating homologous genes from other filamentous ascomycetes or deuteromycetes, such as other Aspergillus species, e.g., A. oryzae, A. foetidus, A. japonicus, A. aculeatus, or A. nidulans. Other non-Aspergillus filamentous ascomycete species include Fusarium species, such as F. graminearum, F. oxysporum, F. solani, F. culmorum (or corresponding teleomorphs) Neurospora crassa, Trichoderma reesei, T. viridae, T. harzianum, T. longibranchiatum, Penicillium janthinellum, P. notatum, P. chrysogenum, P. camemberti, P. roqueforti, Humicola insolen, H. grisea var. thermoidea, H. lanuginosa, Scytalidium thermophilum, Myceliophthora thermophila, and Thielavia terrestris. The gene, or an oligonucleotide based thereon, can be used as probes in southern hybridization to isolate homologous genes of these other species. In particular, such probes can be used under low to high stringency conditions (for example, prehybridization and hybridization at 42° C. in 5×SSPE, 0.3% SDS, 200 μg/ml sheared and denatured salmon sperm DNA, and either 50, 35 or 25% formamide for high, medium and low stringencies, respectively) for hybridization with the genomic or cDNA of the species of interest, following standard southern blotting procedures, in order to identify and isolate the corresponding CPY gene therein. A PCR reaction using the degenerate probes mentioned herein and genomic DNA or first-strand cDNA from a filamentous fungus may also yield a CPY-specific product which could then be used as a probe to clone the corresponding genomic or cDNA. The present gene is particularly useful in the creation of carboxypeptidase-deficient mutants of filamentous ascomycetes such as Aspergillus. This can be achieved in a number of ways. In one method, as described in further detail below, a selectable marker is cloned into the middle of the CPY gene. The disrupted fragment is then released from the parental plasmid using restriction enzymes. The linearized DNA fragment is used to transform the chosen host cell. In the host cell, the homologous ends pair with the host cell chromosome, and the homologous recombination results in a chromosomal gene replacement. Useful selectable markers for use with fungal cell hosts include amdS, pyrG, argB, niaD, sC, and hygB. Alternately, a two-step process can be employed using a two-way selectable marker. In such a process, a plasmid containing a truncated CPY gene and the selectable marker gene is digested with a restriction enzyme which cuts once within the the CPY fragment in order to target integration to the CPY locus during transformation. The transformants are then grown on media which will select for the loss of the selectable marker gene, e.g., when the marker is pyrG, the medium may contain 5-fluorootic acid. The loss of the selectable gene usually occurs by a recombination between the wild type CPY and the introduced truncated CPY gene. Approximately 50% of the resulting strain should have only the truncated CPY gene while the other 50% will contain only the wild type gene. Such methods are described in Rothstein, Meth. Enzymol. 194, 281-301, 1991. The CPY-deficient mutants so created are particularly useful in the expression of heterologous protein. By "heterologous protein" in the present context is meant a protein which is not native to the host cell, a native protein in which modifications have been made to alter the native sequence, or a native protein whose expression is quantitatively altered as a result of a manipulation of the host cell by recombinant DNA techniques. Also encompassed within this term are native proteins for which expression in the mutants involves the use of genetic elements not native to the host cell, or use of native elements which have been manipulated to function in a manner not normally seen in the host cell. As already noted, the production of proteases by a chosen host cell can severely limit the yield of the desired protein by degrading the product before it can be recovered. The elimination or reduction in the amount of CPY produced by a host can therefore substantially increase the yield of any given protein, and can render an otherwise commercially unsuitable host cell commercially feasible for recombinant protein production. In a preferred embodiment, the CPY deficient cells produce at least 25% less, preferably at least 50% less, and most preferably at least 70% less CPY, up to total loss of CPY function, than the corresponding wild-type strain. The mutant fungal cells of the present invention can be used in recombinant protein production in the same manner as the wild-type strains. Those skilled in the art will readily recognize routine variations from the specific embodiments described herein which are useful in adapting the methodology to the strains noted above. A gene of interest can be expressed, in active form, using an expression vector. A useful expression vector contains an element that permits stable integration of the vector into the host cell genome or autonomous replication of the vector in a host cell independent of the genome of the host cell, and preferably one or more phenotypic markers which permit easy selection of transformed host cells. The expression vector may also include control sequences encoding a promoter, ribosome binding site, translation initiation signal, and, optionally, a repressor gene or various activator genes. To permit the secretion of the expressed protein, nucleotides encoding a signal sequence may be inserted prior to the coding sequence of the gene. For expression under the direction of control sequences, a gene to be used according to the invention is operably linked to the control sequences in the proper reading frame. The expression vector may be any vector which may conveniently be subjected to recombinant DNA procedures, and the choice of vector will typically depend on the host cell into which it is to be introduced. In a preferred embodiment of the present invention, the host cell is a strain of the genus Aspergillus. Thus, the vector may be an autonomously replicating vector, i.e. a vector which exists as an extrachromosomal entity, the replication of which is independent of chromosomal replication, e.g. a plasmid, or an extrachromosomal element, minichromosome or an artificial chromosome. Alternatively, the vector may be one which, when introduced into a host cell, is integrated into the host cell genome and replicated together with the chromosome(s) into which it has been integrated. In the vector, the sequence of the gene of interest should be operably connected to a suitable promoter sequence. The promoter may be any DNA sequence which shows transcriptional activity in the host cell of choice and may be derived from genes encoding proteins either homologous or heterologous to the host cell. For transcription in a fungal host, examples of useful promoters are those derived from the gene encoding A. oryzae TAKA amylase, Rhizomucor miehei aspartic proteinase, A. niger neutral α-amylase, A. niger acid stable α-amylase, A. niger or A. awamori glucoamylase (glaA), Rhizomucor miehei lipase, A. oryzae alkaline protease, A. oryzae triose phosphate isomerase or A. nidulans acetamidase. Preferred are the TAKA-amylase and glaA promoters. The expression vector of the invention may also comprise a suitable transcription terminator and, in eukaryotes, polyadenylation sequences operably connected to the DNA sequence encoding the heterologous gene sequence. Termination and polyadenylation sequences may suitably be derived from the same sources as the promoter. The vector may further comprise a DNA sequence enabling the vector to replicate in the host cell in question. Examples of such sequences are the origins of replication of plasmids pUC19, pACYC177, pUB110, pE194, pAMB1 and pIJ702. The vector may also comprise a selectable marker, e.g. a gene the product of which complements a defect in the host cell, or one which confers antibiotic resistance such as ampicillin, kanamycin, chloramphenicol or tetracycline resistance. Examples of Aspergillus selection markers include amdS, pyrG, argB, niaD, sC, and hygB, a marker giving rise to hygromycin resistance. Preferred for use in an Aspergillus host cell are the amdS and pyrG markers of A. nidulans or A. oryzae. Furthermore, selection may be accomplished by co-transformation, e.g. as described in WO 91/17243. It is generally preferred that the expression gives rise to a product which is extracellular. The protein of interest may thus comprise a preregion permitting secretion of the expressed protein into the culture medium. If desirable, this preregion may be native to the protein of the invention or substituted with a different preregion or signal sequence, conveniently accomplished by substitution of the DNA sequences encoding the respective preregions. For example, the preregion may be derived from a glucoamylase or an amylase gene from an Aspergillus species, an amylase gene from a Bacillus species, a lipase or proteinase gene from Rhizomucor miehei, the gene for the α-factor from Saccharomyces cerevisiae or the calf preprochymosin gene. Particularly preferred, when the host is a fungal cell, is the preregion for A. oryzae TAKA amylase, A. niger neutral amylase, the maltogenic amylase form Bacillus NCIB 11837, B. stearothermophilus α-amylase, or Bacillus licheniformis subtilisin. An effective signal sequence is the A. oryzae TAKA amylase signal, the Rhizomucor miehei aspartic proteinase signal and the Rhizomucor miehei lipase signal. The procedures used to ligate the DNA construct of the invention, the promoter, terminator and other elements, respectively, and to insert them into suitable vectors containing the information necessary for replication, are well known to persons skilled in the art (cf., for instance, Sambrook et al. Molecular Cloning, 1989). The CPY-deficient mutants can be used to express any prokaryotic or eukaryotic protein of interest, and are preferably used to express eukaryotic proteins. Of particular interest for these cells is their use in expression of fungal enzymes such as catalase, laccase, phenoloxidase, oxidase, oxidoreductases, cellulase, xylanase, peroxidase, lipase, hydrolase, esterase, cutinase, protease and other proteolytic enzymes, aminopeptidase, carboxypeptidase, phytase, lyase, pectinase and other pectinolytic enzymes, amylase, glucoamylase, α-galactosidase, β-galactosidase, α-glucosidase, β-glucosidase, mannosidase, isomerase, invertase, transferase, ribonuclease, chitinase, and deoxyribonuclease. It will be understood by those skilled in the art that the term "fungal enzymes" includes not only native fungal enzymes, but also those fungal enzymes which have been modified by amino acid substitutions, deletions, additions, or other modifications which may be made to enhance activity, thermostability, pH tolerance and the like. The mutants can also be used to express heterologous proteins of pharmaceutical interest Such as hormones, growth factors, receptors, and the like. The invention will be further illustrated by the following non-limiting examples. EXAMPLES I. Isolation of the Aspergillus niger CPY Gene A. Materials and Methods i. Strains The following biological materials are used in the procedures described below. Escherichia coli K802 (ek4-(nrca), mcrB, hsdR2, galK2, GalT22, supE44, metB1; E. coli SOLR(E14-(mcrA)Δ(mcrCB-hsdSMR-mr r )171, sbcC, recB, recJ, uvrC, umuC::Tn5(kan r ), lac, gyrA96, relA1, thi-1, endA1, λ R F'proABlacI q ZΔM15!Su - , E. coli JM101supE, thi-1, Δ(lacproAB), F'traD36, proAB, lacI q ZΔM15!, E. coli XL-1 Blue recA1, endA1, gyrA96, thi-1, hsdR17, supE44, relA1, lac, F'proAB, lacI q ZΔM15, Tn10(tet R )!, Aspergillus niger Bo-1, A. niger SFAG-2. ii. PCR amplification PCR reactions are run using standard protocols with annealing steps done at 45° C. A. niger Bo-1 genomic DNA is used as template and the following degenerate oligonucleotides are used. Primer 1-1(94-282)-GGIGGICCIGGITGYTC Primer 1-2(94-283)-GGIGGICCIGGITGYAG Primer 2-1(94-284)-CCIAGCCARTTRCADAT Primer 2-2(94-285)-CCYAACCARTTRCADAT Primer 3-1(94-331)-GTIGGITTYTCITAYTCIGG Primer 3-2(94-332)-GTIGGITTYAGYTAYAGYGG Primer 4-1(94-329)-GARTCITAYGCIGGICAYTA Primer 2-1(94-330)-GARAGYTAYGCIGGICAYTA In the above primers, I stands for inosine, Y for C or T, R for A or G, and D for A, G or T. iii. Subcloning PCR products PCR products are subcloned for sequencing using the TA Cloning Kit (Invitrogen) following the manufacturer's protocols. iv. In vivo excision from Lambda Zap II From the CPY cDNA Lambda Zap clones, a plasmid is rescued containing the cDNA inserts in a pBluescript SK-vector by passage through the E. coli strain SOLR following the protocols provided by Stratagene. v. DNA sequencing Nucleotide sequencing is determined using TAQ polymerase cycle-sequencing with fluorescent labeled nucleotides. The sequencing reactions are electrophoresed on an Applied Biosystems automatic DNA sequencer (Model 363A, version 1.2.0). The following CPY specific primers are used, in addition to the M13 reverse (-48) and M13 (-20) forward primers (Sanger et al., J. Mol. Biol. 143: 163-178): ______________________________________94-376 TCGCTGCCAGTCTATGATTGA94-377 ACATCAACCGCAACTTCCTCT94-378 TTGCCAATGAGAACGGACTGC94-379 CGCACTTACCACGGACATCAT94-503 CAAGCATCCTCAAACTATCGT94-504 GAGACGCATGAAGGTGAAGTT94-505 GCCGTCCCTCCCTTCCAGCAG94-506 GTGCCGACGGGTTCTCCAAGC94-507 GCAGCGAGGAAGAGCGTTGTC94-510 GGGTCATTCTCGGGGTCATTG94-511 GACCCCGAGAATGACCCTGTT94-512 GTAGGGCTTCATCCAGTCACC94-513 TCTCACCGTTCTCACCAGTAA94-514 TCCCTCCCCAAGAAGCACAAC94-528 AGCGTCTGGGTTACTGGTGAG94-529 AAGATCGGCCAGGTCAAGTCC94-530 GAGACGGTGGTAGGGCTTCAT94-531 AACGTCGGTTACTCTTACAGC94-532 GTQGTCGGGGCGGCGGTTGTG94-533 TGTTTGAAGAAGAGGGTAAGC94-575 CGCTGCTACTTGATTTTTCTA94-576 CTCAGCGCCAACAGCCTCAAT94-577 ACCTGCAGTCCGTTCTTATTG94-634 TGCGATCGATTCATTCTCATC94-635 GGAGTAACCGACATTGACAGG94-636 CCTGTCAATGTCGGTTACTCC94-637 GTCCCATGGCAACTTCACCTT94-646 CTTCTCACCGTTCTCACCAGT94-647 CGAGACTCGAAGAACCCTAAG______________________________________ B. Results Using A. niger Bo-1 genomic DNA as template PCR reactions are done using various combinations of the CPY specific degenerate oligonucleotides, primers 1-1, 1-2, 2-1, and 2-2 (FIG. 1). All reactions are done using one cycle at 95° C. for 5 minutes, 45° C. for 1 minute and 72° C. for 2 minutes followed by 25 cycles at 95° C. for 1 minute, 45° C. for one minute and 72° C. for 2 minutes. Aliquots (10 μl) of the reactions were electrophoresed on an agarose gel, and in two of the reactions, one with primers 1-2 and 2-1 and one with primers 1-2 and 2-2, an amplification product of approximately 1100 bp is the major species. The predicted size of a product using these oligonucleotide combinations assuming there are no introns within the gene is 900 bp. the 1100 bp amplification product is subcloned and sequenced using the forward and reverse primers. Seven of the subclones are sequenced; however, none of them by homology code for CPY. PCR reactions using various combinations of primers 3-1, 3-2, 4-1, 4-2, 2-1 and 2-2 are run using the same conditions as above. Aliquots are electrophoresed on an agarose gel, and in two of the reactions, one with primers 4-1 and 2-1 and one with primers 4-2 and 2-1, an amplification product of approximately 600 bp is the major species. The expected size for this amplification product based on homology to other carboxypeptidases is 600 bp. The 600 bp amplification product is subcloned and the DNA sequence is determined for 11 of the subclones Using the forward and reverse primers. Nine of the 11 subclones, based on identity of 69% to S. cerevisiae, code for CPY from A. niger. All 9 are identical to one another suggesting there is only one gene for carboxypeptidase in A. niger. The subclone containing the A. niger CPY PCR product of 600 bp is designated pDSY17. A Southern blot of A. niger Bo-1 genomic DNA is probed with the insert from pDSY17. The probe is radiolabeled using a nick-translation kit from Gibco-BRL. Hybridization conditions used are 60° C. in 1.5×SSPE, 1% SDS, 0.5% nonfat milk and 200 μg/ml salmon sperm DNA. The blot is washed at 65° C. for 15 minutes twice in 0.2×SSC, 1% SDS and 0.1% Na pyrophosphate. In the BamHI, HindIII and SAlI digests, single bands of approximately 10, 5.5 and 7 kb, respectively hybridize to the CPY probe. In order to isolate the full gene for CPY, a genomic bank in EMBL4 of A. niger Bo-1 containing approximately 26,000 recombinants is probed with the PCR-derived CPY gene fragment, radiolabeled with the Gibco-BRL nick translation kit. Approximately 28,000 plaques are lifted to filters and probed. Eleven positives from these plates are picked. After purification, 9 of the primary clones still hybridized with the CPY probe. DNA is isolated from the 9 clones, and restriction digests are done in order to begin characterizing them. From the restriction patterns, 7 of the 9 are identical. The other two clones are unique. From Southern digests of the clones, it is determined that 8 of the 9 have the same HindIII fragment of approximately 5.5 kb which hybridizes to the CPY probe. The clone which does not contain the same HindIII fragment contains a larger (>12 kb) HindIII fragment which hybridizes to the CPY probe. The Common HindIII fragment is subcloned for DNA sequencing. The genomic DNA sequence and predicted amino acid sequence is shown in FIG. 1. A cDNA bank in Lambda ZAPII (Stratagene) of A. niger SFAG-2 is also screened. Approximately 42,000 plaques are lifted to filter and probed with the CPY probe as above, and 112 of these plaques appear to hybridize under the stringent conditions defined above. Twenty of the initial positives are picked and rescreened, and upon purification, 18 still hybridize with the CPY probe. From 4 of the positive clones, DNA is isolated using the in vivo excision protocol provided with the Lambda zap kit. The rescued plasmids are digested with EcoRI and electrophoresed on an agarose gel to determine the sizes of the inserts. Two of the clones (2-1 and 3-2) appear to have large enough inserts to contain the full length cDNA for CPY, and each contains two EcoRI fragments of approximately 1700 and 250 bp. The predicted size for a full length cDNA is approximately 1600 bp. The other two cDNA clones (2-2 and 2-4) have smaller inserts; however, they all contain the 250 bp EcoRI fragment. Partial DNA sequences of clones 3-2 and 2-2 are determined, and 3-2 contains the full-length cDNA while clone 2-2 is truncated at the 5' end by about 200 bp. The complete cDNA sequence is determined on both strands (FIG. 2). The cDNA is predicted to code for a CPY precursor of 557 amino acids in length. To date most of the nucleotide differences found between the cDNA and genomic clones are within the wobble which is not surprising since they come from two different A. niger strains. Based on an alignment with CPY from S. cerevisiae, CPY from A. niger appears to have both a signal peptide and a propeptide and the mature CPY protein is either 419 or 420 amino acids in length. A. niger CPY has approximately 65% and 66% identity to CPY from the yeasts S. cerevisiae and C. albicans (Mukhtar et al., Gene 121: 173-177, 1992), respectively. II. Preparation of a CPY-Deficient Mutant In order to create an A. niger strain deleted for CPY, a construct in whichthe A. oryzae pyrG gene is inserted into the coding region of CPY is made (FIG. 3). An ˜6.5 kb HindIII fragment containing almost the entire gene of CPY and ˜6 kb downstream of the gene is subcloned into a pKS+ (Stratagene) derivative in which the PstI site has been destroyed. The resulting recombinant is digested with PstI to delete an 815 bp fragment from the CPY coding region, and the overhangs created by digestion with PstI are blunted by the addition of T4 DNA polymerase and all 4 dNTPs. The resulting blunt-end vector is ligated to an ˜3.8 kb blunt-end fragment obtained by digestion with HindIII followed by a fill-reaction using Klenow fragment. The final construct in which the CPY gene has the pyrG inserted is digested with HindIII to create a linear fragment which is used to transform an A. niger pyrG strain selecting for growth on minimal medium plates. Transformants are screened by Southern blotting to determine which strains contain a disrupted CPY gene. The transformants are further analyzed by Western blotting to look for the absence of CPY intracellularly. Once a strain is identified as containing a disruption of CPY, the effect on heterologous protein is determined. Deposit of Biological Materials The following biological materials have been deposited on Sep. 13, 1994 in Agricultural Research Service Culture Collection (NRRL) 1815 North University Street, Peoria, Ill. 61664. ______________________________________Cell line Accession No.______________________________________E. coli containing NRRL B-21326pDSY23 (EMCC #0120)______________________________________ __________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 4(2) INFORMATION FOR SEQ ID NO: 1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 2068 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: double(D) TOPOLOGY: linear(ii) MOLECULE TYPE: Genomic DNA(vi) ORIGINAL SOURCE:(A) ORGANISM: Aspergillus niger(ix) FEATURE:(A) NAME/KEY: intron(B) LOCATION: 572..632(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: join (571..633)(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 1:TCCTCTGCCTACTCATCCCATCACCATCTCAATTCATACCGCCCCCGTGGGGTTTCAGCA60CCAATGAGAGTCCTTCCAGCTGCTATGCTGGTTGGAGCGGCCACGGCG108MetArgValLeuProAlaAlaMetLeuValGlyAlaAlaThrAla151015GCCGTTCCTCCCTTCCAGCAGGTCCTTGGAGGTAACGGTGCCAAGCAC156AlaValProProPheGlnGlnValLeuGlyGlyAsnGlyAlaLysHis202530GGTGCCGACCATGCGGCCGAGGTCCCTGCGGATCACAGTGCCGACGGG204GlyAlaAspHisAlaAlaGluValProAlaAspHisSerAlaAspGly354045TTCTCCAAGCCGCTGCACGCATTCCAGGAGGAGCTGAAGTCTCTCTCT252PheSerLysProLeuHisAlaPheGlnGluGluLeuLysSerLeuSer505560GACGAGGCTCGTAAGCTTTGGGATGAGGTGGCCAGCTTCTTCCCGGAG300AspGluAlaArgLysLeuTrpAspGluValAlaSerPhePheProGlu657075AGCATGGATCAGAACCCTCTCTTTTCCCTCCCCAAGAAGCACAACCGC348SerMetAspGlnAsnProLeuPheSerLeuProLysLysHisAsnArg80859095CGTCCCGACTCGCACTGGGACCACATCGTCCGCGGCTCCGACGTTCAG396ArgProAspSerHisTrpAspHisIleValArgGlySerAspValGln100105110AGCGTCTGGGTCACTGGTGAGAACGGTGAGAAGGAGCGCGAGGTCGAT444SerValTrpValThrGlyGluAsnGlyGluLysGluArgGluValAsp115120125GGCAAGCTGGAAGCCTATGATCTCAGGGTCAAGAAGACCGATCCTGGC492GlyLysLeuGluAlaTyrAspLeuArgValLysLysThrAspProGly130135140TCTCTTGGCATCGACCCCGGCGTGAAGCAGTACACCGGTTATCTCGAT540SerLeuGlyIleAspProGlyValLysGlnTyrThrGlyTyrLeuAsp145150155GACAACGAGAATGATAAGCATTTGTTCTACGTAAGCACACCTTGGTTCAA590AspAsnGluAsnAspLysHisLeuPheTyr160165GATCACGCTTTTTATATGCTCTGGATATCTAACGCAACTTAGTGGTTCTTCGAG644TrpPhePheGlu170TCTCGCAATGACCCCGAGAATGATCCCGTTGTTCTGTGGCTGAACGGT692SerArgAsnAspProGluAsnAspProValValLeuTrpLeuAsnGly175180185GGCCCTGGGTGCTCTTCCCTCACCGGTCTCTTCATGGAGCTTGGCCCT740GlyProGlyCysSerSerLeuThrGlyLeuPheMetGluLeuGlyPro190195200205AGCAGCATCAACAAGAAGATCCAGCCGGTCTACAATGACTACGCTTGG788SerSerIleAsnLysLysIleGlnProValTyrAsnAspTyrAlaTrp210215220AACTCCAACGCGTCCGTGATCTTCCTTGACCAGCCTGTCAATGTCGGT836AsnSerAsnAlaSerValIlePheLeuAspGlnProValAsnValGly225230235TACTCCTACAGTAACTCTGCTGTCAGCGACACGGTCGCTGCTGGCAAG884TyrSerTyrSerAsnSerAlaValSerAspThrValAlaAlaGlyLys240245250GACGTCTATGCCTTGCTTACCCTCTTCTTCAAACAATTCCCCGAGTAT932AspValTyrAlaLeuLeuThrLeuPhePheLysGlnPheProGluTyr255260265GCTAAGCAGGACTTCCACATTGCCGGTGAATCTTATGCTGGTCACTAT980AlaLysGlnAspPheHisIleAlaGlyGluSerTyrAlaGlyHisTyr270275280285ATCCCCGTCTTCGCTTCGGAGATCCTGTCTCACAAGAAGCGCAACATC1028IleProValPheAlaSerGluIleLeuSerHisLysLysArgAsnIle290295300AACCTGCAGTCCGTTCTCATTGGCAACGGTCTCACCGACGGATACACC1076AsnLeuGlnSerValLeuIleGlyAsnGlyLeuThrAspGlyTyrThr305310315CAGTACGAGTACTACCGTCCCATGGCCTGCGGTGACGGCGGTTACCCA1124GlnTyrGluTyrTyrArgProMetAlaCysGlyAspGlyGlyTyrPro320325330GCTGTCTTGGACGAGAGCTCCTGCCAGTCCATGGACAACGCTCTTCCT1172AlaValLeuAspGluSerSerCysGlnSerMetAspAsnAlaLeuPro335340345CGCTGCCAGTCTATGATTGAGTCTTGCTACAGTTCCGAGAGCGCTTGG1220ArgCysGlnSerMetIleGluSerCysTyrSerSerGluSerAlaTrp350355360365GTTTGTGTCCCGGCCTCCATCTACTGTAACAACGCCCTCCTTGCCCCT1268ValCysValProAlaSerIleTyrCysAsnAsnAlaLeuLeuAlaPro370375380TACCAGCGCACTGGGCAGAACGTCTATGATGTCCGTGGTAAGTGCGAG1316TyrGlnArgThrGlyGlnAsnValTyrAspValArgGlyLysCysGlu385390395GATAGCTCTAACCTTTGCTACTCGGCTATGGGCTACGTCAGCGACTAC1364AspSerSerAsnLeuCysTyrSerAlaMetGlyTyrValSerAspTyr400405410CTGAACAAGCCCGAAGTCATCGAGGCTGTTGGCGCTGAGGTCAACGGC1412LeuAsnLysProGluValIleGluAlaValGlyAlaGluValAsnGly415420425TACGACTCGTGCAACTTTGACATCAACCGCAACTTCCTCTTCCACGGT1460TyrAspSerCysAsnPheAspIleAsnArgAsnPheLeuPheHisGly430435440445GACTGGATGAAGCCCTACCACCGCCTCGTTCCGGGACTCCTGGAGCAG1508AspTrpMetLysProTyrHisArgLeuValProGlyLeuLeuGluGln450455460ATCCCTGTCTTGATCTATGCCGGTGATGCTGATTTCATTTGCAACTGG1556IleProValLeuIleTyrAlaGlyAspAlaAspPheIleCysAsnTrp465470475CTGGGCAACAAGGCCTGGACTGAAGCCCTGGAGTGGCCCGGACAGGCT1604LeuGlyAsnLysAlaTrpThrGluAlaLeuGluTrpProGlyGlnAla480485490GAATATGCCTCCGCTGAGCTGGAGGATCTGGTCATTGTCGACAATGAG1652GluTyrAlaSerAlaGluLeuGluAspLeuValIleValAspAsnGlu495500505CACACGGGCAAGAAGATTGGCCAGGTTAAGTCCCATGGCAACTTCACC1700HisThrGlyLysLysIleGlyGlnValLysSerHisGlyAsnPheThr510515520525TTCATGCGTCTCTATGGTGGTGGCCACATGGTCCCGATGGACCAGCCC1748PheMetArgLeuTyrGlyGlyGlyHisMetValProMetAspGlnPro530535540GAGTCGAGTCTCGAGTTCTTCAACCGCTGGTTGGGAGGTGAATGGTTC1796GluSerSerLeuGluPhePheAsnArgTrpLeuGlyGlyGluTrpPhe545550555TAAAGACGTGCTACCACCGCATATAGACTTTCTGGTCATTTCGGTGACACTGC1849AGATATGTTTCTTAACGATAGTTTGAGCATGCTTGTCAATGCCCACTAGTCCCGATCCTT1909ATATGTTGCATGGTATCTATGAGTTTTGTCACTATAGTGCATTATACATGTGTACTTCGT1969ATGAGAATGAATCGATCGCATTTACACGCATATAAATAGTACCCACCTCCGCCTGGACAT2029GAATTAGGCCCGGCCAGTCGTTTACATACAGTGCTAGAA2068(2) INFORMATION FOR SEQ ID NO: 2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 557 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(vi) ORIGINAL SOURCE:(A) ORGANISM: Aspergillus Niger(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 2:MetArgValLeuProAlaAlaMetLeuValGlyAlaAlaThrAlaAla151015ValProProPheGlnGlnValLeuGlyGlyAsnGlyAlaLysHisGly202530AlaAspHisAlaAlaGluValProAlaAspHisSerAlaAspGlyPhe354045SerLysProLeuHisAlaPheGlnGluGluLeuLysSerLeuSerAsp505560GluAlaArgLysLeuTrpAspGluValAlaSerPhePheProGluSer65707580MetAspGlnAsnProLeuPheSerLeuProLysLysHisAsnArgArg859095ProAspSerHisTrpAspHisIleValArgGlySerAspValGlnSer100105110ValTrpValThrGlyGluAsnGlyGluLysGluArgGluValAspGly115120125LysLeuGluAlaTyrAspLeuArgValLysLysThrAspProGlySer130135140LeuGlyIleAspProGlyValLysGlnTyrThrGlyTyrLeuAspAsp145150155160AsnGluAsnAspLysHisLeuPheTyrTrpPhePheGluSerArgAsn165170175AspProGluAsnAspProValValLeuTrpLeuAsnGlyGlyProGly180185190CysSerSerLeuThrGlyLeuPheMetGluLeuGlyProSerSerIle195200205AsnLysLysIleGlnProValTyrAsnAspTyrAlaTrpAsnSerAsn210215220AlaSerValIlePheLeuAspGlnProValAsnValGlyTyrSerTyr225230235240SerAsnSerAlaValSerAspThrValAlaAlaGlyLysAspValTyr245250255AlaLeuLeuThrLeuPhePheLysGlnPheProGluTyrAlaLysGln260265270AspPheHisIleAlaGlyGluSerTyrAlaGlyHisTyrIleProVal275280285PheAlaSerGluIleLeuSerHisLysLysArgAsnIleAsnLeuGln290295300SerValLeuIleGlyAsnGlyLeuThrAspGlyTyrThrGlnTyrGlu305310315320TyrTyrArgProMetAlaCysGlyAspGlyGlyTyrProAlaValLeu325330335AspGluSerSerCysGlnSerMetAspAsnAlaLeuProArgCysGln340345350SerMetIleGluSerCysTyrSerSerGluSerAlaTrpValCysVal355360365ProAlaSerIleTyrCysAsnAsnAlaLeuLeuAlaProTyrGlnArg370375380ThrGlyGlnAsnValTyrAspValArgGlyLysCysGluAspSerSer385390395400AsnLeuCysTyrSerAlaMetGlyTyrValSerAspTyrLeuAsnLys405410415ProGluValIleGluAlaValGlyAlaGluValAsnGlyTyrAspSer420425430CysAsnPheAspIleAsnArgAsnPheLeuPheHisGlyAspTrpMet435440445LysProTyrHisArgLeuValProGlyLeuLeuGluGlnIleProVal450455460LeuIleTyrAlaGlyAspAlaAspPheIleCysAsnTrpLeuGlyAsn465470475480LysAlaTrpThrGluAlaLeuGluTrpProGlyGlnAlaGluTyrAla485490495SerAlaGluLeuGluAspLeuValIleValAspAsnGluHisThrGly500505510LysLysIleGlyGlnValLysSerHisGlyAsnPheThrPheMetArg515520525LeuTyrGlyGlyGlyHisMetValProMetAspGlnProGluSerSer530535540LeuGluPhePheAsnArgTrpLeuGlyGlyGluTrpPhe545550555(2) INFORMATION FOR SEQ ID NO: 3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 2002 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: double(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(vi) ORIGINAL SOURCE:(A) ORGANISM: Aspergillus niger(ix) FEATURE:(A) NAME/KEY: intron(B) LOCATION: 349..411(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: join (348..412)(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 3:GCGGCCGCTGCTACTTGCTTTTTCTAATTTGATACTTTTGTGTCCGTACCGTACCTTCCA60GACCGCAAGGTACCCATCCTCTACCTACTCATCCCATCATCATCTCGATTTCATACCAAC120CCCGTTGGGTTTCAACACAATGAGAGTTCTTCCAGCTGCTATGCTGGTTGGA172MetArgValLeuProAlaAlaMetLeuValGly1510GCGGGCACTGCGGCCGTCCCTCCCTTCCAGCAGGTCCTTGGAGGTAAC220AlaGlyThrAlaAlaValProProPheGlnGlnValLeuGlyGlyAsn152025GGTGCCAAGCACGGTGCCGACCATGCGGCCGAGGTCCCTGCGGATCAC268GlyAlaLysHisGlyAlaAspHisAlaAlaGluValProAlaAspHis303540AGTGCCGACGGGTTCTCCAAGCCGCTGCACGCATTCCAGGAGGAGCTG316SerAlaAspGlyPheSerLysProLeuHisAlaPheGlnGluGluLeu455055AAGTCTCTCTCTGATGAGGCTCGTAAGCTCTGGGATGAGGTTGCTAGC364LysSerLeuSerAspGluAlaArgLysLeuTrpAspGluValAlaSer60657075TTCTTCCCGGAGAGCATGGATCAGAACCCTCTCTTCTCCCTCCCCAAG412PhePheProGluSerMetAspGlnAsnProLeuPheSerLeuProLys808590AAGCACAACCGCCGCCCCGACCACCACTGGGACCACATCGTCCGCGGC460LysHisAsnArgArgProAspHisHisTrpAspHisIleValArgGly95100105TCCGACGTTCAGAGCGTCTGGGTTACTGGTGAGAACGGTGAGAAGGAG508SerAspValGlnSerValTrpValThrGlyGluAsnGlyGluLysGlu110115120CGTGAGGTCGATGGCAAGCTGGAAGCCTATGATCTCAGGGTCAAGAAG556ArgGluValAspGlyLysLeuGluAlaTyrAspLeuArgValLysLys125130135ACCGATCCTAGCTCTCTTGGCATCGACCCTGGCGTAAAGCAGTACACC604ThrAspProSerSerLeuGlyIleAspProGlyValLysGlnTyrThr140145150155GGTTATCTCGATGACAACGAGAACGACAAGCATCTGTTCTACTGGTTC652GlyTyrLeuAspAspAsnGluAsnAspLysHisLeuPheTyrTrpPhe160165170TTCGAGTCTCGCAATGACCCCGAGAATGACCCTGTTGTTCTGTGGCTG700PheGluSerArgAsnAspProGluAsnAspProValValLeuTrpLeu175180185AACGGTGGCCCTGGATGCTCTTCCCTCACCGGTCTTTTCATGGAGCTC748AsnGlyGlyProGlyCysSerSerLeuThrGlyLeuPheMetGluLeu190195200GGCCCTAGCAGCATCAACAAGAAGATCCAGCCGGTCTACAACGACTAC796GlyProSerSerIleAsnLysLysIleGlnProValTyrAsnAspTyr205210215GCTTGGAACTCCAACGCGTCCGTGATCTTCCTTGACCAGCCTGTCAAC844AlaTrpAsnSerAsnAlaSerValIlePheLeuAspGlnProValAsn220225230235GTCGGTTACTCTTACAGCAACTCTGCTGTCAGCGACACCGTTGCTGCT892ValGlyTyrSerTyrSerAsnSerAlaValSerAspThrValAlaAla240245250GGCAAGGACGTCTATGCCTTGCTTACCCTCTTCTTCAAACAATTCCCC940GlyLysAspValTyrAlaLeuLeuThrLeuPhePheLysGlnPhePro255260265GAGTATGCCAAGCAGGACTTCCACATTGCCGGTGAATCCTATGCTGGT988GluTyrAlaLysGlnAspPheHisIleAlaGlyGluSerTyrAlaGly270275280CACTATATCCCCGTCTTTGCTTCGGAGATTTTGTCTCACAAGAAGCGC1036HisTyrIleProValPheAlaSerGluIleLeuSerHisLysLysArg285290295AACATCAACCTGCAGTCCGTTCTTATTGGCAACGGTCTCACCGACGGT1084AsnIleAsnLeuGlnSerValLeuIleGlyAsnGlyLeuThrAspGly300305310315CTCACTCAGTACGAGTACTACCGTCCCATGGCCTGTGGTGACGGTGGT1132LeuThrGlnTyrGluTyrTyrArgProMetAlaCysGlyAspGlyGly320325330TACCCAGCTGTCTTGGACGAGGGCTCCTGCCAGGCCATGGACAACGCC1180TyrProAlaValLeuAspGluGlySerCysGlnAlaMetAspAsnAla335340345CTTCCTCGCTGCCAGTCTATGATTGAGTCTTGCTATAGTTCCGAGAGC1228LeuProArgCysGlnSerMetIleGluSerCysTyrSerSerGluSer350355360GCTTGGGTTTGTGTCCCGGCCTCCATCTACTGTAACAACGCCCTCCTT1276AlaTrpValCysValProAlaSerIleTyrCysAsnAsnAlaLeuLeu365370375GCCCCTTACCAGCGCACCGGACAGAACGTCTACGATGTTCGTGGTAAG1324AlaProTyrGlnArgThrGlyGlnAsnValTyrAspValArgGlyLys380385390395TGCGAGGATAGCTCCAACCTCTGCTACTCGGCCATGGGCTACGTCAGC1372CysGluAspSerSerAsnLeuCysTyrSerAlaMetGlyTyrValSer400405410GACTACCTGAACAAGACCGAGGTCATTGAGGCTGTTGGCGCTGAGGTC1420AspTyrLeuAsnLysThrGluValIleGluAlaValGlyAlaGluVal415420425AACGGCTACGACTCGTGCAACTTTGACATCAACCGCAACTTCCTCTTC1468AsnGlyTyrAspSerCysAsnPheAspIleAsnArgAsnPheLeuPhe430435440CACGGTGACTGGATGAAGCCCTACCACCGTCTCGTTCCGGGACTCCTG1516HisGlyAspTrpMetLysProTyrHisArgLeuValProGlyLeuLeu445450455GAGCAGATCCCTGTCCTGATCTACGCTGGTGACGCCGATTTCATCTGC1564GluGlnIleProValLeuIleTyrAlaGlyAspAlaAspPheIleCys460465470475AACTGGCTGGGCAACAAGGCCTGGACTGAAGCCCTTGAGTGGCCCGGA1612AsnTrpLeuGlyAsnLysAlaTrpThrGluAlaLeuGluTrpProGly480485490CAGGCTGAATATGCCTCCGCTAAGCTGGAGGACCTGGTCGTGGTCGAG1660GlnAlaGluTyrAlaSerAlaLysLeuGluAspLeuValValValGlu495500505AATGAGCACAAGGGCAAGAAGATCGGCCAGGTCAAGTCCCATGGCAAC1708AsnGluHisLysGlyLysLysIleGlyGlnValLysSerHisGlyAsn510515520TTCACCTTCATGCGTCTCTATGGCGGTGGCCACATGGTCCCGATGGAC1756PheThrPheMetArgLeuTyrGlyGlyGlyHisMetValProMetAsp525530535CAACCCGAGTCGAGTCTTGAATTCTTCAACCGCTGGTTGGGAGGTGAA1804GlnProGluSerSerLeuGluPhePheAsnArgTrpLeuGlyGlyGlu540545550555TGGTTTTAAAGACGTGCTATCACCGCATATAGACTTTCCGGTCATTTCGGTGACACTGC1863TrpPheAGATATGTTTCTTAACGATAGTTTGAGGATGCTTGTCAATGCCCACTAATCCCGAGCCTT1923ATGTTACATGGTATCTATGAGTTTGTCATTATAGTGCATTATGCATTTGTACTCCGTACG1983AGAATGAATCAGCGGCCGC2002(2) INFORMATION FOR SEQ ID NO: 4:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 557 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(vi) ORIGINAL SOURCE:(A) ORGANISM: Aspergillus Niger(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 4:MetArgValLeuProAlaAlaMetLeuValGlyAlaGlyThrAlaAla151015ValProProPheGlnGlnValLeuGlyGlyAsnGlyAlaLysHisGly202530AlaAspHisAlaAlaGluValProAlaAspHisSerAlaAspGlyPhe354045SerLysProLeuHisAlaPheGlnGluGluLeuLysSerLeuSerAsp505560GluAlaArgLysLeuTrpAspGluValAlaSerPhePheProGluSer65707580MetAspGlnAsnProLeuPheSerLeuProLysLysHisAsnArgArg859095ProAspHisHisTrpAspHisIleValArgGlySerAspValGlnSer100105110ValTrpValThrGlyGluAsnGlyGluLysGluArgGluValAspGly115120125LysLeuGluAlaTyrAspLeuArgValLysLysThrAspProSerSer130135140LeuGlyIleAspProGlyValLysGlnTyrThrGlyTyrLeuAspAsp145150155160AsnGluAsnAspLysHisLeuPheTyrTrpPhePheGluSerArgAsn165170175AspProGluAsnAspProValValLeuTrpLeuAsnGlyGlyProGly180185190CysSerSerLeuThrGlyLeuPheMetGluLeuGlyProSerSerIle195200205AsnLysLysIleGlnProValTyrAsnAspTyrAlaTrpAsnSerAsn210215220AlaSerValIlePheLeuAspGlnProValAsnValGlyTyrSerTyr225230235240SerAsnSerAlaValSerAspThrValAlaAlaGlyLysAspValTyr245250255AlaLeuLeuThrLeuPhePheLysGlnPheProGluTyrAlaLysGln260265270AspPheHisIleAlaGlyGluSerTyrAlaGlyHisTyrIleProVal275280285PheAlaSerGluIleLeuSerHisLysLysArgAsnIleAsnLeuGln290295300SerValLeuIleGlyAsnGlyLeuThrAspGlyLeuThrGlnTyrGlu305310315320TyrTyrArgProMetAlaCysGlyAspGlyGlyTyrProAlaValLeu325330335AspGluGlySerCysGlnAlaMetAspAsnAlaLeuProArgCysGln340345350SerMetIleGluSerCysTyrSerSerGluSerAlaTrpValCysVal355360365ProAlaSerIleTyrCysAsnAsnAlaLeuLeuAlaProTyrGlnArg370375380ThrGlyGlnAsnValTyrAspValArgGlyLysCysGluAspSerSer385390395400AsnLeuCysTyrSerAlaMetGlyTyrValSerAspTyrLeuAsnLys405410415ThrGluValIleGluAlaValGlyAlaGluValAsnGlyTyrAspSer420425430CysAsnPheAspIleAsnArgAsnPheLeuPheHisGlyAspTrpMet435440445LysProTyrHisArgLeuValProGlyLeuLeuGluGlnIleProVal450455460LeuIleTyrAlaGlyAspAlaAspPheIleCysAsnTrpLeuGlyAsn465470475480LysAlaTrpThrGluAlaLeuGluTrpProGlyGlnAlaGluTyrAla485490495SerAlaLysLeuGluAspLeuValValValGluAsnGluHisLysGly500505510LysLysIleGlyGlnValLysSerHisGlyAsnPheThrPheMetArg515520525LeuTyrGlyGlyGlyHisMetValProMetAspGlnProGluSerSer530535540LeuGluPhePheAsnArgTrpLeuGlyGlyGluTrpPhe545550555__________________________________________________________________________
The present invention relates to a gene encoding an ascomycete or deuteromycete carboxypeptidase Y gene, and host cells modified so as to produce reduced amounts of carboxypeptidase.
Condense the core contents of the given document.
[ "This is a divisional application of Ser.", "No. 08/309,341, filed Sep. 20, 1994, now U.S. Pat. No. 5,594,119, the contents of which are incorporated herein by reference in their entirety.", "FIELD OF THE INVENTION The present invention relates to a gene encoding a fungal vacuolar protease.", "In particular, the invention relates to a carboxypeptidase gene of a filamentous ascomycete or deuteromycete fungus, such as those of the genus Aspergillus.", "BACKGROUND OF THE INVENTION The fungal vacuole is an acidic organelle that contains many hydrolases, including several proteases, and is essentially equivalent to the mammalian lysosome.", "Several of the hydrolases have been identified and characterized in one or more species of fungi, particularly in yeast;", "these include protease A (PEP4 or PrA), protease B (PrB), aminopeptidase (APE), dipeptidyl aminopeptidase B (DPAP B), carboxypeptidase Y (CPY), and carboxypeptidase S (CPS).", "Most of the vacuolar hydrolases are glycoproteins which are synthesized as inactive precursors.", "In fact, all the aforementioned proteases with the exception of APE have signal peptides that lead to transit through the secretory pathway.", "In the late golgi, vacuolar proteins are sorted from secretory proteins and eventually delivered to the vacuole.", "In addition to a signal peptide, most vacuolar proteins also have a propeptide which is cleaved upon delivery to the vacuole to generate the mature active enzyme.", "It has been demonstrated that the amino acid information in PrA and CPY required for vacuolar targeting is present within the propeptide (Johnson et al.", ", Cell 48: 875-885, 1987;", "Rothman et al.", "PNAS USA 83: 3248-3252, 1989;", "Valls et al.", ", Cell 48: 887-897, 1989;", "Valls et al.", "J. Cell Biol.", "111: 361-368, 1987).", "For CPY a string of four amino acid residues (QRPL) has been shown to be required for localization to the vacuole (Valls et al.", ", J. Cell Biol.", "111: 361-368, 1990).", "Once delivered to the vacuole, proteinase A (pep4) cleaves the propeptide of CPY and PrB leading to the activation of the proteases (Ammerer et al.", ", Mol.", "Cell.", "Biol.", "6: 2490-2499, 1986;", "Woolford et al.", ", Mol.", "Cell.", "Biol.", "6: 2500-2510, 1986).", "In S. cerevisiae, three classes of mutants which mislocalize or missort vacuolar proteins have been identified (Bankaitis et al.", ", PNAS USA 83: 9075-9079, 1986;", "Robinson et al.", ", Mol.", "Cell.", "Biol.", ", 8: 4936-4948, 1988;", "Rothman et al.", ", EMBO J. 8: 2057-2065, 1989;", "Rothman and Stevens, Cell 47: 1041-1051, 1986).", "These mutants are called rids or vacuolar protein sorting mutants.", "Several of these mutants are isolated using a selection based on the observation that overexpression of a vacuolar protease due to a high copy number on a plasmid leads to a secretion of vacuolar proteases (Stevens et al.", ", J. Cell Biol.", "102: 1551-1557, 1986;", "Rothman et al, PNAS USA 83: 3248-3242, 1986).", "This suggests that it is possible to saturate the sorting machinery within the late golgi.", "In S. cerevisiae, it has also been demonstrated that strains deleted for PEP4, CPY and PrB produce higher levels of heterologous proteins due to a decrease in proteolysis of the desired product.", "Therefore, the vacuolar proteases in question are important from a commercial point of view because many of the fungi which produce them are used for recombinant production of heterologous proteins.", "The presence of these proteases in fermentation is undesirable, in that they can degrade the protein of interest, thereby significantly reducing yield.", "Elimination of the function of any given protease is facilitated by the disruption or deletion of the gene encoding it;", "however, doing so first requires identification and isolation of the corresponding gene in the host species of interest.", "As noted above, a few such genes have been isolated from various yeast strains;", "however, the genes encoding vacuolar proteases in the filamentous ascomycetes or deuteromycetes are less well known.", "For example, PEPC (Frederick et al.", ", Gene 125: 57-64, 1993) and PEPE (Jarai et al.", ", Gene 145: 171-178, 1994) genes coding for two other vacuolar proteases from Aspergilus niger have been isolated.", "PEPC codes for a proteinase B(PrB) homologue, and PEPE codes for a proteinase A homologue.", "The gene PEP4 from Neurospora crassa coding for a PrA homologue has also been cloned (Bowman, 17th Fungal Genetics Conference, 1993).", "For the first time herein is described the gene encoding a vacuolar CPY from a filamentous ascomycete or deuteromycete.", "SUMMARY OF THE INVENTION The present invention relates to a nucleic acid construct comprising a sequence encoding a filamentous ascomycete or deuteromycete carboxypeptidase Y, as well as the recombinantly produced protein encoded thereby.", "As used herein, "nucleic acid construct"", "is intended to indicate any nucleic acid molecule of cDNA, genomic DNA, synthetic DNA or RNA origin.", "The term "construct"", "is intended to indicated a nucleic acid segment which may be single-or double-stranded, and which may be isolated in complete or partial form from a naturally occurring gene or which has been modified to contain segments of DNA which are combined and juxtaposed in a manner which would not otherwise exist in nature.", "The construct may optionally contain other nucleic acid segments.", "In a preferred embodiment, the sequence encodes a carboxypeptidase of the genus Aspergillus.", "The invention also provides a method for producing a non-carboxypeptidase-producing filamentous ascomycete or deuteromycete cell, which comprises disrupting or deleting the carboxypeptidase gene so as to prevent the expression of a functional enzyme, or treating the gene by classical mutagenesis using physical or chemical treatments to generate cells which are reduced or lacking in their ability to produce CPY.", "In addition, the invention also encompasses a filamentous ascomycete or deuteromycete which is unable to produce a functional carboxypeptidase enzyme, or which produces the carboxypeptidase in reduced amounts relative to the amount produced by the wild-type strain.", "Such organisms provide the basis for an improved method of recombinant protein production, wherein the carboxypeptidase-deficient microorganism is transformed with the nucleic acid construct encoding the protein of interest, and cultured under conditions conducive to the expression of the protein.", "BRIEF DESCRIPTION OF THE FIGURES FIG. 1 illustrates the DNA sequence and translation of the A. niger Bo-1 genomic CPY clone.", "FIG. 2 illustrates the DNA sequence and translation of A. niger SFAG 2 CPY cDNA.", "The predicted site for signal peptidase cleavage and the N-terminus of mature CPY are indicated.", "FIG. 3 illustrates the construct used in disruption CPY.", "DETAILED DESCRIPTION OF THE INVENTION Attempts to isolate an Aspergillus carboxypeptidase Y are initiated by designing a series of degenerate oligonucleotides, using the sequences of S. cerevisiae CPY, Penicillium janthinellum carboxypeptidase S1 (Svedsen et al.", ", FEBS 333: 39-43, 1993, and malt carboxypeptidase-MIII (S.", "o slashed.", "rensen et al.", ", Carlsberg Res.", "Commun.", "54: 193-202, 1993).", "The oligonucleotide sequences are provided the examples below.", "These sequences are used as primers in various combinations in a PCR reaction using Aspergillus niger strain Bo-1 genomic DNA as a template.", "Two of the reactions (with primers 1-1 and 2-1;", "and 1-2 and 2-2) yield an 1100 bp amplification product, which is subcloned and sequenced, but none of the subclones has significant homology to CPY to be identified as the gene of interest.", "Further PCR reactions with primers 3-1, 3-2, 4-1, 4-2, 2-1 and 2-2 are then made.", "In two of the reactions (primers 4-1 and 2-1;", "and 4-2 and 2-1) a 600 bp amplification product is obtained.", "This product is subcloned and 11 of the subclones sequenced;", "nine of these subclones are identical, and have homology to carboxypeptidaseY genes from other sources.", "The insert from one of the subclones is used to probe A. niger genomic DNA;", "hybridization with single bands is observed with BamHI.", "HindIII, and SalI digests, suggesting that a single CPY gene exists in A. niger.", "Hybridizations are done at 65° C. in 1.5×SSPE, 1.0% SDS, 0.5% non-fat milk and 200 μg/ml salmon sperm DNA.", "An A. niger genomic DNA bank in EMBL4 is prepared and probed with the PCR CPY-derived gene fragment ( 32 P-labeled), in order to isolate a full length gene.", "Out of approximately 28,000 plaques, 11 positives are picked;", "nine of these still hybridize with the probe after purification.", "A 5.5 HindIII fragment common to a majority of these clones is identified as the A. niger CPY gene.", "This fragment is subcloned and sequenced;", "the sequence of the fragment, including the CPY coding region and predicted amino acid sequence, is provided in FIG. 1. Subsequently, a cDNA bank from a different A. niger strain is also screened.", "At least one full-length clone is identified from this library as well.", "This clone is sequenced and the sequence is depicted in FIG. 2. Both DNA sequences predict a CPY precursor of 557 amino acids in length.", "Based on a comparison with the homologous gene from S. cerevisiae, CPY from A. niger appears to have a pre-propeptide of 137 or 138 amino acids.", "The gene contains one intron of 61 base pairs.", "A comparison of the two A. niger sequences will show some difference in amino acid sequence, which presumably reflects the different strains from which the genomic and cDNA clones are isolated.", "A comparison with the amino acid sequences of the corresponding CPY genes of S. cerevisiae and C. albicans shows a 65% and 66% identity, respectively.", "The present invention is not limited to the use of the sequences disclosed in FIGS. 1 and 2.", "First, the invention also encompasses nucleotide sequences which produce the same amino acid sequence as depicted in FIG. 1 or 2, but differ by virtue of the degeneracy of the genetic code.", "In addition, the difference in amino acid sequence shown for two strains of the same species shows that variation within the sequence of a single species is tolerated, and using the techniques described herein, such variants can readily be identified.", "Therefore, when "A.", "niger"", "is referred to in this context, it will be understood to encompass all such variations.", "In particular, the invention also encompasses any variant nucleotide sequence, and the protein encoded thereby, which protein retains at least about an 80%, preferably about 85%, and most preferably at least about 90-95% homology with the amino acid sequence depicted in FIG. 1 or 2, and which qualitatively retains the activity of the sequence described herein.", "Useful variants within the categories defined above include, for example, ones in which conservative amino acid substitutions have been made, which substitutions do not significantly affect the activity of the protein.", "By conservative substitution is meant that amino acids of the same class may be substituted by any other of that class.", "For example, the nonpolar aliphatic residues Ala, Val, Leu, and Ile may be interchanged, as may be the basic residues Lys and Arg, or the acidic residues Asp and Glu.", "Similarly, Ser and Thr are conservative substitutions for each other, as are Asn and Gln.", "In addition, the isolated gene provides a means for isolating homologous genes from other filamentous ascomycetes or deuteromycetes, such as other Aspergillus species, e.g., A. oryzae, A. foetidus, A. japonicus, A. aculeatus, or A. nidulans.", "Other non-Aspergillus filamentous ascomycete species include Fusarium species, such as F. graminearum, F. oxysporum, F. solani, F. culmorum (or corresponding teleomorphs) Neurospora crassa, Trichoderma reesei, T. viridae, T. harzianum, T. longibranchiatum, Penicillium janthinellum, P. notatum, P. chrysogenum, P. camemberti, P. roqueforti, Humicola insolen, H. grisea var.", "thermoidea, H. lanuginosa, Scytalidium thermophilum, Myceliophthora thermophila, and Thielavia terrestris.", "The gene, or an oligonucleotide based thereon, can be used as probes in southern hybridization to isolate homologous genes of these other species.", "In particular, such probes can be used under low to high stringency conditions (for example, prehybridization and hybridization at 42° C. in 5×SSPE, 0.3% SDS, 200 μg/ml sheared and denatured salmon sperm DNA, and either 50, 35 or 25% formamide for high, medium and low stringencies, respectively) for hybridization with the genomic or cDNA of the species of interest, following standard southern blotting procedures, in order to identify and isolate the corresponding CPY gene therein.", "A PCR reaction using the degenerate probes mentioned herein and genomic DNA or first-strand cDNA from a filamentous fungus may also yield a CPY-specific product which could then be used as a probe to clone the corresponding genomic or cDNA.", "The present gene is particularly useful in the creation of carboxypeptidase-deficient mutants of filamentous ascomycetes such as Aspergillus.", "This can be achieved in a number of ways.", "In one method, as described in further detail below, a selectable marker is cloned into the middle of the CPY gene.", "The disrupted fragment is then released from the parental plasmid using restriction enzymes.", "The linearized DNA fragment is used to transform the chosen host cell.", "In the host cell, the homologous ends pair with the host cell chromosome, and the homologous recombination results in a chromosomal gene replacement.", "Useful selectable markers for use with fungal cell hosts include amdS, pyrG, argB, niaD, sC, and hygB.", "Alternately, a two-step process can be employed using a two-way selectable marker.", "In such a process, a plasmid containing a truncated CPY gene and the selectable marker gene is digested with a restriction enzyme which cuts once within the the CPY fragment in order to target integration to the CPY locus during transformation.", "The transformants are then grown on media which will select for the loss of the selectable marker gene, e.g., when the marker is pyrG, the medium may contain 5-fluorootic acid.", "The loss of the selectable gene usually occurs by a recombination between the wild type CPY and the introduced truncated CPY gene.", "Approximately 50% of the resulting strain should have only the truncated CPY gene while the other 50% will contain only the wild type gene.", "Such methods are described in Rothstein, Meth.", "Enzymol.", "194, 281-301, 1991.", "The CPY-deficient mutants so created are particularly useful in the expression of heterologous protein.", "By "heterologous protein"", "in the present context is meant a protein which is not native to the host cell, a native protein in which modifications have been made to alter the native sequence, or a native protein whose expression is quantitatively altered as a result of a manipulation of the host cell by recombinant DNA techniques.", "Also encompassed within this term are native proteins for which expression in the mutants involves the use of genetic elements not native to the host cell, or use of native elements which have been manipulated to function in a manner not normally seen in the host cell.", "As already noted, the production of proteases by a chosen host cell can severely limit the yield of the desired protein by degrading the product before it can be recovered.", "The elimination or reduction in the amount of CPY produced by a host can therefore substantially increase the yield of any given protein, and can render an otherwise commercially unsuitable host cell commercially feasible for recombinant protein production.", "In a preferred embodiment, the CPY deficient cells produce at least 25% less, preferably at least 50% less, and most preferably at least 70% less CPY, up to total loss of CPY function, than the corresponding wild-type strain.", "The mutant fungal cells of the present invention can be used in recombinant protein production in the same manner as the wild-type strains.", "Those skilled in the art will readily recognize routine variations from the specific embodiments described herein which are useful in adapting the methodology to the strains noted above.", "A gene of interest can be expressed, in active form, using an expression vector.", "A useful expression vector contains an element that permits stable integration of the vector into the host cell genome or autonomous replication of the vector in a host cell independent of the genome of the host cell, and preferably one or more phenotypic markers which permit easy selection of transformed host cells.", "The expression vector may also include control sequences encoding a promoter, ribosome binding site, translation initiation signal, and, optionally, a repressor gene or various activator genes.", "To permit the secretion of the expressed protein, nucleotides encoding a signal sequence may be inserted prior to the coding sequence of the gene.", "For expression under the direction of control sequences, a gene to be used according to the invention is operably linked to the control sequences in the proper reading frame.", "The expression vector may be any vector which may conveniently be subjected to recombinant DNA procedures, and the choice of vector will typically depend on the host cell into which it is to be introduced.", "In a preferred embodiment of the present invention, the host cell is a strain of the genus Aspergillus.", "Thus, the vector may be an autonomously replicating vector, i.e. a vector which exists as an extrachromosomal entity, the replication of which is independent of chromosomal replication, e.g. a plasmid, or an extrachromosomal element, minichromosome or an artificial chromosome.", "Alternatively, the vector may be one which, when introduced into a host cell, is integrated into the host cell genome and replicated together with the chromosome(s) into which it has been integrated.", "In the vector, the sequence of the gene of interest should be operably connected to a suitable promoter sequence.", "The promoter may be any DNA sequence which shows transcriptional activity in the host cell of choice and may be derived from genes encoding proteins either homologous or heterologous to the host cell.", "For transcription in a fungal host, examples of useful promoters are those derived from the gene encoding A. oryzae TAKA amylase, Rhizomucor miehei aspartic proteinase, A. niger neutral α-amylase, A. niger acid stable α-amylase, A. niger or A. awamori glucoamylase (glaA), Rhizomucor miehei lipase, A. oryzae alkaline protease, A. oryzae triose phosphate isomerase or A. nidulans acetamidase.", "Preferred are the TAKA-amylase and glaA promoters.", "The expression vector of the invention may also comprise a suitable transcription terminator and, in eukaryotes, polyadenylation sequences operably connected to the DNA sequence encoding the heterologous gene sequence.", "Termination and polyadenylation sequences may suitably be derived from the same sources as the promoter.", "The vector may further comprise a DNA sequence enabling the vector to replicate in the host cell in question.", "Examples of such sequences are the origins of replication of plasmids pUC19, pACYC177, pUB110, pE194, pAMB1 and pIJ702.", "The vector may also comprise a selectable marker, e.g. a gene the product of which complements a defect in the host cell, or one which confers antibiotic resistance such as ampicillin, kanamycin, chloramphenicol or tetracycline resistance.", "Examples of Aspergillus selection markers include amdS, pyrG, argB, niaD, sC, and hygB, a marker giving rise to hygromycin resistance.", "Preferred for use in an Aspergillus host cell are the amdS and pyrG markers of A. nidulans or A. oryzae.", "Furthermore, selection may be accomplished by co-transformation, e.g. as described in WO 91/17243.", "It is generally preferred that the expression gives rise to a product which is extracellular.", "The protein of interest may thus comprise a preregion permitting secretion of the expressed protein into the culture medium.", "If desirable, this preregion may be native to the protein of the invention or substituted with a different preregion or signal sequence, conveniently accomplished by substitution of the DNA sequences encoding the respective preregions.", "For example, the preregion may be derived from a glucoamylase or an amylase gene from an Aspergillus species, an amylase gene from a Bacillus species, a lipase or proteinase gene from Rhizomucor miehei, the gene for the α-factor from Saccharomyces cerevisiae or the calf preprochymosin gene.", "Particularly preferred, when the host is a fungal cell, is the preregion for A. oryzae TAKA amylase, A. niger neutral amylase, the maltogenic amylase form Bacillus NCIB 11837, B. stearothermophilus α-amylase, or Bacillus licheniformis subtilisin.", "An effective signal sequence is the A. oryzae TAKA amylase signal, the Rhizomucor miehei aspartic proteinase signal and the Rhizomucor miehei lipase signal.", "The procedures used to ligate the DNA construct of the invention, the promoter, terminator and other elements, respectively, and to insert them into suitable vectors containing the information necessary for replication, are well known to persons skilled in the art (cf.", ", for instance, Sambrook et al.", "Molecular Cloning, 1989).", "The CPY-deficient mutants can be used to express any prokaryotic or eukaryotic protein of interest, and are preferably used to express eukaryotic proteins.", "Of particular interest for these cells is their use in expression of fungal enzymes such as catalase, laccase, phenoloxidase, oxidase, oxidoreductases, cellulase, xylanase, peroxidase, lipase, hydrolase, esterase, cutinase, protease and other proteolytic enzymes, aminopeptidase, carboxypeptidase, phytase, lyase, pectinase and other pectinolytic enzymes, amylase, glucoamylase, α-galactosidase, β-galactosidase, α-glucosidase, β-glucosidase, mannosidase, isomerase, invertase, transferase, ribonuclease, chitinase, and deoxyribonuclease.", "It will be understood by those skilled in the art that the term "fungal enzymes"", "includes not only native fungal enzymes, but also those fungal enzymes which have been modified by amino acid substitutions, deletions, additions, or other modifications which may be made to enhance activity, thermostability, pH tolerance and the like.", "The mutants can also be used to express heterologous proteins of pharmaceutical interest Such as hormones, growth factors, receptors, and the like.", "The invention will be further illustrated by the following non-limiting examples.", "EXAMPLES I. Isolation of the Aspergillus niger CPY Gene A. Materials and Methods i. Strains The following biological materials are used in the procedures described below.", "Escherichia coli K802 (ek4-(nrca), mcrB, hsdR2, galK2, GalT22, supE44, metB1;", "E. coli SOLR(E14-(mcrA)Δ(mcrCB-hsdSMR-mr r )171, sbcC, recB, recJ, uvrC, umuC::Tn5(kan r ), lac, gyrA96, relA1, thi-1, endA1, λ R F'proABlacI q ZΔM15!", "Su - , E. coli JM101supE, thi-1, Δ(lacproAB), F'traD36, proAB, lacI q ZΔM15!", ", E. coli XL-1 Blue recA1, endA1, gyrA96, thi-1, hsdR17, supE44, relA1, lac, F'proAB, lacI q ZΔM15, Tn10(tet R )!", ", Aspergillus niger Bo-1, A. niger SFAG-2.", "ii.", "PCR amplification PCR reactions are run using standard protocols with annealing steps done at 45° C. A. niger Bo-1 genomic DNA is used as template and the following degenerate oligonucleotides are used.", "Primer 1-1(94-282)-GGIGGICCIGGITGYTC Primer 1-2(94-283)-GGIGGICCIGGITGYAG Primer 2-1(94-284)-CCIAGCCARTTRCADAT Primer 2-2(94-285)-CCYAACCARTTRCADAT Primer 3-1(94-331)-GTIGGITTYTCITAYTCIGG Primer 3-2(94-332)-GTIGGITTYAGYTAYAGYGG Primer 4-1(94-329)-GARTCITAYGCIGGICAYTA Primer 2-1(94-330)-GARAGYTAYGCIGGICAYTA In the above primers, I stands for inosine, Y for C or T, R for A or G, and D for A, G or T. iii.", "Subcloning PCR products PCR products are subcloned for sequencing using the TA Cloning Kit (Invitrogen) following the manufacturer's protocols.", "iv.", "In vivo excision from Lambda Zap II From the CPY cDNA Lambda Zap clones, a plasmid is rescued containing the cDNA inserts in a pBluescript SK-vector by passage through the E. coli strain SOLR following the protocols provided by Stratagene.", "v. DNA sequencing Nucleotide sequencing is determined using TAQ polymerase cycle-sequencing with fluorescent labeled nucleotides.", "The sequencing reactions are electrophoresed on an Applied Biosystems automatic DNA sequencer (Model 363A, version 1.2[.", "].0).", "The following CPY specific primers are used, in addition to the M13 reverse (-48) and M13 (-20) forward primers (Sanger et al.", ", J. Mol.", "Biol.", "143: 163-178): ______________________________________94-376 TCGCTGCCAGTCTATGATTGA94-377 ACATCAACCGCAACTTCCTCT94-378 TTGCCAATGAGAACGGACTGC94-379 CGCACTTACCACGGACATCAT94-503 CAAGCATCCTCAAACTATCGT94-504 GAGACGCATGAAGGTGAAGTT94-505 GCCGTCCCTCCCTTCCAGCAG94-506 GTGCCGACGGGTTCTCCAAGC94-507 GCAGCGAGGAAGAGCGTTGTC94-510 GGGTCATTCTCGGGGTCATTG94-511 GACCCCGAGAATGACCCTGTT94-512 GTAGGGCTTCATCCAGTCACC94-513 TCTCACCGTTCTCACCAGTAA94-514 TCCCTCCCCAAGAAGCACAAC94-528 AGCGTCTGGGTTACTGGTGAG94-529 AAGATCGGCCAGGTCAAGTCC94-530 GAGACGGTGGTAGGGCTTCAT94-531 AACGTCGGTTACTCTTACAGC94-532 GTQGTCGGGGCGGCGGTTGTG94-533 TGTTTGAAGAAGAGGGTAAGC94-575 CGCTGCTACTTGATTTTTCTA94-576 CTCAGCGCCAACAGCCTCAAT94-577 ACCTGCAGTCCGTTCTTATTG94-634 TGCGATCGATTCATTCTCATC94-635 GGAGTAACCGACATTGACAGG94-636 CCTGTCAATGTCGGTTACTCC94-637 GTCCCATGGCAACTTCACCTT94-646 CTTCTCACCGTTCTCACCAGT94-647 CGAGACTCGAAGAACCCTAAG______________________________________ B. Results Using A. niger Bo-1 genomic DNA as template PCR reactions are done using various combinations of the CPY specific degenerate oligonucleotides, primers 1-1, 1-2, 2-1, and 2-2 (FIG.", "1).", "All reactions are done using one cycle at 95° C. for 5 minutes, 45° C. for 1 minute and 72° C. for 2 minutes followed by 25 cycles at 95° C. for 1 minute, 45° C. for one minute and 72° C. for 2 minutes.", "Aliquots (10 μl) of the reactions were electrophoresed on an agarose gel, and in two of the reactions, one with primers 1-2 and 2-1 and one with primers 1-2 and 2-2, an amplification product of approximately 1100 bp is the major species.", "The predicted size of a product using these oligonucleotide combinations assuming there are no introns within the gene is 900 bp.", "the 1100 bp amplification product is subcloned and sequenced using the forward and reverse primers.", "Seven of the subclones are sequenced;", "however, none of them by homology code for CPY.", "PCR reactions using various combinations of primers 3-1, 3-2, 4-1, 4-2, 2-1 and 2-2 are run using the same conditions as above.", "Aliquots are electrophoresed on an agarose gel, and in two of the reactions, one with primers 4-1 and 2-1 and one with primers 4-2 and 2-1, an amplification product of approximately 600 bp is the major species.", "The expected size for this amplification product based on homology to other carboxypeptidases is 600 bp.", "The 600 bp amplification product is subcloned and the DNA sequence is determined for 11 of the subclones Using the forward and reverse primers.", "Nine of the 11 subclones, based on identity of 69% to S. cerevisiae, code for CPY from A. niger.", "All 9 are identical to one another suggesting there is only one gene for carboxypeptidase in A. niger.", "The subclone containing the A. niger CPY PCR product of 600 bp is designated pDSY17.", "A Southern blot of A. niger Bo-1 genomic DNA is probed with the insert from pDSY17.", "The probe is radiolabeled using a nick-translation kit from Gibco-BRL.", "Hybridization conditions used are 60° C. in 1.5×SSPE, 1% SDS, 0.5% nonfat milk and 200 μg/ml salmon sperm DNA.", "The blot is washed at 65° C. for 15 minutes twice in 0.2×SSC, 1% SDS and 0.1% Na pyrophosphate.", "In the BamHI, HindIII and SAlI digests, single bands of approximately 10, 5.5 and 7 kb, respectively hybridize to the CPY probe.", "In order to isolate the full gene for CPY, a genomic bank in EMBL4 of A. niger Bo-1 containing approximately 26,000 recombinants is probed with the PCR-derived CPY gene fragment, radiolabeled with the Gibco-BRL nick translation kit.", "Approximately 28,000 plaques are lifted to filters and probed.", "Eleven positives from these plates are picked.", "After purification, 9 of the primary clones still hybridized with the CPY probe.", "DNA is isolated from the 9 clones, and restriction digests are done in order to begin characterizing them.", "From the restriction patterns, 7 of the 9 are identical.", "The other two clones are unique.", "From Southern digests of the clones, it is determined that 8 of the 9 have the same HindIII fragment of approximately 5.5 kb which hybridizes to the CPY probe.", "The clone which does not contain the same HindIII fragment contains a larger (>12 kb) HindIII fragment which hybridizes to the CPY probe.", "The Common HindIII fragment is subcloned for DNA sequencing.", "The genomic DNA sequence and predicted amino acid sequence is shown in FIG. 1. A cDNA bank in Lambda ZAPII (Stratagene) of A. niger SFAG-2 is also screened.", "Approximately 42,000 plaques are lifted to filter and probed with the CPY probe as above, and 112 of these plaques appear to hybridize under the stringent conditions defined above.", "Twenty of the initial positives are picked and rescreened, and upon purification, 18 still hybridize with the CPY probe.", "From 4 of the positive clones, DNA is isolated using the in vivo excision protocol provided with the Lambda zap kit.", "The rescued plasmids are digested with EcoRI and electrophoresed on an agarose gel to determine the sizes of the inserts.", "Two of the clones (2-1 and 3-2) appear to have large enough inserts to contain the full length cDNA for CPY, and each contains two EcoRI fragments of approximately 1700 and 250 bp.", "The predicted size for a full length cDNA is approximately 1600 bp.", "The other two cDNA clones (2-2 and 2-4) have smaller inserts;", "however, they all contain the 250 bp EcoRI fragment.", "Partial DNA sequences of clones 3-2 and 2-2 are determined, and 3-2 contains the full-length cDNA while clone 2-2 is truncated at the 5'", "end by about 200 bp.", "The complete cDNA sequence is determined on both strands (FIG.", "2).", "The cDNA is predicted to code for a CPY precursor of 557 amino acids in length.", "To date most of the nucleotide differences found between the cDNA and genomic clones are within the wobble which is not surprising since they come from two different A. niger strains.", "Based on an alignment with CPY from S. cerevisiae, CPY from A. niger appears to have both a signal peptide and a propeptide and the mature CPY protein is either 419 or 420 amino acids in length.", "A. niger CPY has approximately 65% and 66% identity to CPY from the yeasts S. cerevisiae and C. albicans (Mukhtar et al.", ", Gene 121: 173-177, 1992), respectively.", "II.", "Preparation of a CPY-Deficient Mutant In order to create an A. niger strain deleted for CPY, a construct in whichthe A. oryzae pyrG gene is inserted into the coding region of CPY is made (FIG.", "3).", "An ˜6.5 kb HindIII fragment containing almost the entire gene of CPY and ˜6 kb downstream of the gene is subcloned into a pKS+ (Stratagene) derivative in which the PstI site has been destroyed.", "The resulting recombinant is digested with PstI to delete an 815 bp fragment from the CPY coding region, and the overhangs created by digestion with PstI are blunted by the addition of T4 DNA polymerase and all 4 dNTPs.", "The resulting blunt-end vector is ligated to an ˜3.8 kb blunt-end fragment obtained by digestion with HindIII followed by a fill-reaction using Klenow fragment.", "The final construct in which the CPY gene has the pyrG inserted is digested with HindIII to create a linear fragment which is used to transform an A. niger pyrG strain selecting for growth on minimal medium plates.", "Transformants are screened by Southern blotting to determine which strains contain a disrupted CPY gene.", "The transformants are further analyzed by Western blotting to look for the absence of CPY intracellularly.", "Once a strain is identified as containing a disruption of CPY, the effect on heterologous protein is determined.", "Deposit of Biological Materials The following biological materials have been deposited on Sep. 13, 1994 in Agricultural Research Service Culture Collection (NRRL) 1815 North University Street, Peoria, Ill.", "61664.", "______________________________________Cell line Accession No.______________________________________E.", "coli containing NRRL B-21326pDSY23 (EMCC #0120)______________________________________ __________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 4(2) INFORMATION FOR SEQ ID NO: 1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 2068 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: double(D) TOPOLOGY: linear(ii) MOLECULE TYPE: Genomic DNA(vi) ORIGINAL SOURCE:(A) ORGANISM: Aspergillus niger(ix) FEATURE:(A) NAME/KEY: intron(B) LOCATION: 572.", "].632(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: join (571.", "].633)(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 1:TCCTCTGCCTACTCATCCCATCACCATCTCAATTCATACCGCCCCCGTGGGGTTTCAGCA60CCAATGAGAGTCCTTCCAGCTGCTATGCTGGTTGGAGCGGCCACGGCG108MetArgValLeuProAlaAlaMetLeuValGlyAlaAlaThrAla151015GCCGTTCCTCCCTTCCAGCAGGTCCTTGGAGGTAACGGTGCCAAGCAC156AlaValProProPheGlnGlnValLeuGlyGlyAsnGlyAlaLysHis202530GGTGCCGACCATGCGGCCGAGGTCCCTGCGGATCACAGTGCCGACGGG204GlyAlaAspHisAlaAlaGluValProAlaAspHisSerAlaAspGly354045TTCTCCAAGCCGCTGCACGCATTCCAGGAGGAGCTGAAGTCTCTCTCT252PheSerLysProLeuHisAlaPheGlnGluGluLeuLysSerLeuSer505560GACGAGGCTCGTAAGCTTTGGGATGAGGTGGCCAGCTTCTTCCCGGAG300AspGluAlaArgLysLeuTrpAspGluValAlaSerPhePheProGlu657075AGCATGGATCAGAACCCTCTCTTTTCCCTCCCCAAGAAGCACAACCGC348SerMetAspGlnAsnProLeuPheSerLeuProLysLysHisAsnArg80859095CGTCCCGACTCGCACTGGGACCACATCGTCCGCGGCTCCGACGTTCAG396ArgProAspSerHisTrpAspHisIleValArgGlySerAspValGln100105110AGCGTCTGGGTCACTGGTGAGAACGGTGAGAAGGAGCGCGAGGTCGAT444SerValTrpValThrGlyGluAsnGlyGluLysGluArgGluValAsp115120125GGCAAGCTGGAAGCCTATGATCTCAGGGTCAAGAAGACCGATCCTGGC492GlyLysLeuGluAlaTyrAspLeuArgValLysLysThrAspProGly130135140TCTCTTGGCATCGACCCCGGCGTGAAGCAGTACACCGGTTATCTCGAT540SerLeuGlyIleAspProGlyValLysGlnTyrThrGlyTyrLeuAsp145150155GACAACGAGAATGATAAGCATTTGTTCTACGTAAGCACACCTTGGTTCAA590AspAsnGluAsnAspLysHisLeuPheTyr160165GATCACGCTTTTTATATGCTCTGGATATCTAACGCAACTTAGTGGTTCTTCGAG644TrpPhePheGlu170TCTCGCAATGACCCCGAGAATGATCCCGTTGTTCTGTGGCTGAACGGT692SerArgAsnAspProGluAsnAspProValValLeuTrpLeuAsnGly175180185GGCCCTGGGTGCTCTTCCCTCACCGGTCTCTTCATGGAGCTTGGCCCT740GlyProGlyCysSerSerLeuThrGlyLeuPheMetGluLeuGlyPro190195200205AGCAGCATCAACAAGAAGATCCAGCCGGTCTACAATGACTACGCTTGG788SerSerIleAsnLysLysIleGlnProValTyrAsnAspTyrAlaTrp210215220AACTCCAACGCGTCCGTGATCTTCCTTGACCAGCCTGTCAATGTCGGT836AsnSerAsnAlaSerValIlePheLeuAspGlnProValAsnValGly225230235TACTCCTACAGTAACTCTGCTGTCAGCGACACGGTCGCTGCTGGCAAG884TyrSerTyrSerAsnSerAlaValSerAspThrValAlaAlaGlyLys240245250GACGTCTATGCCTTGCTTACCCTCTTCTTCAAACAATTCCCCGAGTAT932AspValTyrAlaLeuLeuThrLeuPhePheLysGlnPheProGluTyr255260265GCTAAGCAGGACTTCCACATTGCCGGTGAATCTTATGCTGGTCACTAT980AlaLysGlnAspPheHisIleAlaGlyGluSerTyrAlaGlyHisTyr270275280285ATCCCCGTCTTCGCTTCGGAGATCCTGTCTCACAAGAAGCGCAACATC1028IleProValPheAlaSerGluIleLeuSerHisLysLysArgAsnIle290295300AACCTGCAGTCCGTTCTCATTGGCAACGGTCTCACCGACGGATACACC1076AsnLeuGlnSerValLeuIleGlyAsnGlyLeuThrAspGlyTyrThr305310315CAGTACGAGTACTACCGTCCCATGGCCTGCGGTGACGGCGGTTACCCA1124GlnTyrGluTyrTyrArgProMetAlaCysGlyAspGlyGlyTyrPro320325330GCTGTCTTGGACGAGAGCTCCTGCCAGTCCATGGACAACGCTCTTCCT1172AlaValLeuAspGluSerSerCysGlnSerMetAspAsnAlaLeuPro335340345CGCTGCCAGTCTATGATTGAGTCTTGCTACAGTTCCGAGAGCGCTTGG1220ArgCysGlnSerMetIleGluSerCysTyrSerSerGluSerAlaTrp350355360365GTTTGTGTCCCGGCCTCCATCTACTGTAACAACGCCCTCCTTGCCCCT1268ValCysValProAlaSerIleTyrCysAsnAsnAlaLeuLeuAlaPro370375380TACCAGCGCACTGGGCAGAACGTCTATGATGTCCGTGGTAAGTGCGAG1316TyrGlnArgThrGlyGlnAsnValTyrAspValArgGlyLysCysGlu385390395GATAGCTCTAACCTTTGCTACTCGGCTATGGGCTACGTCAGCGACTAC1364AspSerSerAsnLeuCysTyrSerAlaMetGlyTyrValSerAspTyr400405410CTGAACAAGCCCGAAGTCATCGAGGCTGTTGGCGCTGAGGTCAACGGC1412LeuAsnLysProGluValIleGluAlaValGlyAlaGluValAsnGly415420425TACGACTCGTGCAACTTTGACATCAACCGCAACTTCCTCTTCCACGGT1460TyrAspSerCysAsnPheAspIleAsnArgAsnPheLeuPheHisGly430435440445GACTGGATGAAGCCCTACCACCGCCTCGTTCCGGGACTCCTGGAGCAG1508AspTrpMetLysProTyrHisArgLeuValProGlyLeuLeuGluGln450455460ATCCCTGTCTTGATCTATGCCGGTGATGCTGATTTCATTTGCAACTGG1556IleProValLeuIleTyrAlaGlyAspAlaAspPheIleCysAsnTrp465470475CTGGGCAACAAGGCCTGGACTGAAGCCCTGGAGTGGCCCGGACAGGCT1604LeuGlyAsnLysAlaTrpThrGluAlaLeuGluTrpProGlyGlnAla480485490GAATATGCCTCCGCTGAGCTGGAGGATCTGGTCATTGTCGACAATGAG1652GluTyrAlaSerAlaGluLeuGluAspLeuValIleValAspAsnGlu495500505CACACGGGCAAGAAGATTGGCCAGGTTAAGTCCCATGGCAACTTCACC1700HisThrGlyLysLysIleGlyGlnValLysSerHisGlyAsnPheThr510515520525TTCATGCGTCTCTATGGTGGTGGCCACATGGTCCCGATGGACCAGCCC1748PheMetArgLeuTyrGlyGlyGlyHisMetValProMetAspGlnPro530535540GAGTCGAGTCTCGAGTTCTTCAACCGCTGGTTGGGAGGTGAATGGTTC1796GluSerSerLeuGluPhePheAsnArgTrpLeuGlyGlyGluTrpPhe545550555TAAAGACGTGCTACCACCGCATATAGACTTTCTGGTCATTTCGGTGACACTGC1849AGATATGTTTCTTAACGATAGTTTGAGCATGCTTGTCAATGCCCACTAGTCCCGATCCTT1909ATATGTTGCATGGTATCTATGAGTTTTGTCACTATAGTGCATTATACATGTGTACTTCGT1969ATGAGAATGAATCGATCGCATTTACACGCATATAAATAGTACCCACCTCCGCCTGGACAT2029GAATTAGGCCCGGCCAGTCGTTTACATACAGTGCTAGAA2068(2) INFORMATION FOR SEQ ID NO: 2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 557 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(vi) ORIGINAL SOURCE:(A) ORGANISM: Aspergillus Niger(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 2:MetArgValLeuProAlaAlaMetLeuValGlyAlaAlaThrAlaAla151015ValProProPheGlnGlnValLeuGlyGlyAsnGlyAlaLysHisGly202530AlaAspHisAlaAlaGluValProAlaAspHisSerAlaAspGlyPhe354045SerLysProLeuHisAlaPheGlnGluGluLeuLysSerLeuSerAsp505560GluAlaArgLysLeuTrpAspGluValAlaSerPhePheProGluSer65707580MetAspGlnAsnProLeuPheSerLeuProLysLysHisAsnArgArg859095ProAspSerHisTrpAspHisIleValArgGlySerAspValGlnSer100105110ValTrpValThrGlyGluAsnGlyGluLysGluArgGluValAspGly115120125LysLeuGluAlaTyrAspLeuArgValLysLysThrAspProGlySer130135140LeuGlyIleAspProGlyValLysGlnTyrThrGlyTyrLeuAspAsp145150155160AsnGluAsnAspLysHisLeuPheTyrTrpPhePheGluSerArgAsn165170175AspProGluAsnAspProValValLeuTrpLeuAsnGlyGlyProGly180185190CysSerSerLeuThrGlyLeuPheMetGluLeuGlyProSerSerIle195200205AsnLysLysIleGlnProValTyrAsnAspTyrAlaTrpAsnSerAsn210215220AlaSerValIlePheLeuAspGlnProValAsnValGlyTyrSerTyr225230235240SerAsnSerAlaValSerAspThrValAlaAlaGlyLysAspValTyr245250255AlaLeuLeuThrLeuPhePheLysGlnPheProGluTyrAlaLysGln260265270AspPheHisIleAlaGlyGluSerTyrAlaGlyHisTyrIleProVal275280285PheAlaSerGluIleLeuSerHisLysLysArgAsnIleAsnLeuGln290295300SerValLeuIleGlyAsnGlyLeuThrAspGlyTyrThrGlnTyrGlu305310315320TyrTyrArgProMetAlaCysGlyAspGlyGlyTyrProAlaValLeu325330335AspGluSerSerCysGlnSerMetAspAsnAlaLeuProArgCysGln340345350SerMetIleGluSerCysTyrSerSerGluSerAlaTrpValCysVal355360365ProAlaSerIleTyrCysAsnAsnAlaLeuLeuAlaProTyrGlnArg370375380ThrGlyGlnAsnValTyrAspValArgGlyLysCysGluAspSerSer385390395400AsnLeuCysTyrSerAlaMetGlyTyrValSerAspTyrLeuAsnLys405410415ProGluValIleGluAlaValGlyAlaGluValAsnGlyTyrAspSer420425430CysAsnPheAspIleAsnArgAsnPheLeuPheHisGlyAspTrpMet435440445LysProTyrHisArgLeuValProGlyLeuLeuGluGlnIleProVal450455460LeuIleTyrAlaGlyAspAlaAspPheIleCysAsnTrpLeuGlyAsn465470475480LysAlaTrpThrGluAlaLeuGluTrpProGlyGlnAlaGluTyrAla485490495SerAlaGluLeuGluAspLeuValIleValAspAsnGluHisThrGly500505510LysLysIleGlyGlnValLysSerHisGlyAsnPheThrPheMetArg515520525LeuTyrGlyGlyGlyHisMetValProMetAspGlnProGluSerSer530535540LeuGluPhePheAsnArgTrpLeuGlyGlyGluTrpPhe545550555(2) INFORMATION FOR SEQ ID NO: 3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 2002 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: double(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(vi) ORIGINAL SOURCE:(A) ORGANISM: Aspergillus niger(ix) FEATURE:(A) NAME/KEY: intron(B) LOCATION: 349.", "].411(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: join (348.", "].412)(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 3:GCGGCCGCTGCTACTTGCTTTTTCTAATTTGATACTTTTGTGTCCGTACCGTACCTTCCA60GACCGCAAGGTACCCATCCTCTACCTACTCATCCCATCATCATCTCGATTTCATACCAAC120CCCGTTGGGTTTCAACACAATGAGAGTTCTTCCAGCTGCTATGCTGGTTGGA172MetArgValLeuProAlaAlaMetLeuValGly1510GCGGGCACTGCGGCCGTCCCTCCCTTCCAGCAGGTCCTTGGAGGTAAC220AlaGlyThrAlaAlaValProProPheGlnGlnValLeuGlyGlyAsn152025GGTGCCAAGCACGGTGCCGACCATGCGGCCGAGGTCCCTGCGGATCAC268GlyAlaLysHisGlyAlaAspHisAlaAlaGluValProAlaAspHis303540AGTGCCGACGGGTTCTCCAAGCCGCTGCACGCATTCCAGGAGGAGCTG316SerAlaAspGlyPheSerLysProLeuHisAlaPheGlnGluGluLeu455055AAGTCTCTCTCTGATGAGGCTCGTAAGCTCTGGGATGAGGTTGCTAGC364LysSerLeuSerAspGluAlaArgLysLeuTrpAspGluValAlaSer60657075TTCTTCCCGGAGAGCATGGATCAGAACCCTCTCTTCTCCCTCCCCAAG412PhePheProGluSerMetAspGlnAsnProLeuPheSerLeuProLys808590AAGCACAACCGCCGCCCCGACCACCACTGGGACCACATCGTCCGCGGC460LysHisAsnArgArgProAspHisHisTrpAspHisIleValArgGly95100105TCCGACGTTCAGAGCGTCTGGGTTACTGGTGAGAACGGTGAGAAGGAG508SerAspValGlnSerValTrpValThrGlyGluAsnGlyGluLysGlu110115120CGTGAGGTCGATGGCAAGCTGGAAGCCTATGATCTCAGGGTCAAGAAG556ArgGluValAspGlyLysLeuGluAlaTyrAspLeuArgValLysLys125130135ACCGATCCTAGCTCTCTTGGCATCGACCCTGGCGTAAAGCAGTACACC604ThrAspProSerSerLeuGlyIleAspProGlyValLysGlnTyrThr140145150155GGTTATCTCGATGACAACGAGAACGACAAGCATCTGTTCTACTGGTTC652GlyTyrLeuAspAspAsnGluAsnAspLysHisLeuPheTyrTrpPhe160165170TTCGAGTCTCGCAATGACCCCGAGAATGACCCTGTTGTTCTGTGGCTG700PheGluSerArgAsnAspProGluAsnAspProValValLeuTrpLeu175180185AACGGTGGCCCTGGATGCTCTTCCCTCACCGGTCTTTTCATGGAGCTC748AsnGlyGlyProGlyCysSerSerLeuThrGlyLeuPheMetGluLeu190195200GGCCCTAGCAGCATCAACAAGAAGATCCAGCCGGTCTACAACGACTAC796GlyProSerSerIleAsnLysLysIleGlnProValTyrAsnAspTyr205210215GCTTGGAACTCCAACGCGTCCGTGATCTTCCTTGACCAGCCTGTCAAC844AlaTrpAsnSerAsnAlaSerValIlePheLeuAspGlnProValAsn220225230235GTCGGTTACTCTTACAGCAACTCTGCTGTCAGCGACACCGTTGCTGCT892ValGlyTyrSerTyrSerAsnSerAlaValSerAspThrValAlaAla240245250GGCAAGGACGTCTATGCCTTGCTTACCCTCTTCTTCAAACAATTCCCC940GlyLysAspValTyrAlaLeuLeuThrLeuPhePheLysGlnPhePro255260265GAGTATGCCAAGCAGGACTTCCACATTGCCGGTGAATCCTATGCTGGT988GluTyrAlaLysGlnAspPheHisIleAlaGlyGluSerTyrAlaGly270275280CACTATATCCCCGTCTTTGCTTCGGAGATTTTGTCTCACAAGAAGCGC1036HisTyrIleProValPheAlaSerGluIleLeuSerHisLysLysArg285290295AACATCAACCTGCAGTCCGTTCTTATTGGCAACGGTCTCACCGACGGT1084AsnIleAsnLeuGlnSerValLeuIleGlyAsnGlyLeuThrAspGly300305310315CTCACTCAGTACGAGTACTACCGTCCCATGGCCTGTGGTGACGGTGGT1132LeuThrGlnTyrGluTyrTyrArgProMetAlaCysGlyAspGlyGly320325330TACCCAGCTGTCTTGGACGAGGGCTCCTGCCAGGCCATGGACAACGCC1180TyrProAlaValLeuAspGluGlySerCysGlnAlaMetAspAsnAla335340345CTTCCTCGCTGCCAGTCTATGATTGAGTCTTGCTATAGTTCCGAGAGC1228LeuProArgCysGlnSerMetIleGluSerCysTyrSerSerGluSer350355360GCTTGGGTTTGTGTCCCGGCCTCCATCTACTGTAACAACGCCCTCCTT1276AlaTrpValCysValProAlaSerIleTyrCysAsnAsnAlaLeuLeu365370375GCCCCTTACCAGCGCACCGGACAGAACGTCTACGATGTTCGTGGTAAG1324AlaProTyrGlnArgThrGlyGlnAsnValTyrAspValArgGlyLys380385390395TGCGAGGATAGCTCCAACCTCTGCTACTCGGCCATGGGCTACGTCAGC1372CysGluAspSerSerAsnLeuCysTyrSerAlaMetGlyTyrValSer400405410GACTACCTGAACAAGACCGAGGTCATTGAGGCTGTTGGCGCTGAGGTC1420AspTyrLeuAsnLysThrGluValIleGluAlaValGlyAlaGluVal415420425AACGGCTACGACTCGTGCAACTTTGACATCAACCGCAACTTCCTCTTC1468AsnGlyTyrAspSerCysAsnPheAspIleAsnArgAsnPheLeuPhe430435440CACGGTGACTGGATGAAGCCCTACCACCGTCTCGTTCCGGGACTCCTG1516HisGlyAspTrpMetLysProTyrHisArgLeuValProGlyLeuLeu445450455GAGCAGATCCCTGTCCTGATCTACGCTGGTGACGCCGATTTCATCTGC1564GluGlnIleProValLeuIleTyrAlaGlyAspAlaAspPheIleCys460465470475AACTGGCTGGGCAACAAGGCCTGGACTGAAGCCCTTGAGTGGCCCGGA1612AsnTrpLeuGlyAsnLysAlaTrpThrGluAlaLeuGluTrpProGly480485490CAGGCTGAATATGCCTCCGCTAAGCTGGAGGACCTGGTCGTGGTCGAG1660GlnAlaGluTyrAlaSerAlaLysLeuGluAspLeuValValValGlu495500505AATGAGCACAAGGGCAAGAAGATCGGCCAGGTCAAGTCCCATGGCAAC1708AsnGluHisLysGlyLysLysIleGlyGlnValLysSerHisGlyAsn510515520TTCACCTTCATGCGTCTCTATGGCGGTGGCCACATGGTCCCGATGGAC1756PheThrPheMetArgLeuTyrGlyGlyGlyHisMetValProMetAsp525530535CAACCCGAGTCGAGTCTTGAATTCTTCAACCGCTGGTTGGGAGGTGAA1804GlnProGluSerSerLeuGluPhePheAsnArgTrpLeuGlyGlyGlu540545550555TGGTTTTAAAGACGTGCTATCACCGCATATAGACTTTCCGGTCATTTCGGTGACACTGC1863TrpPheAGATATGTTTCTTAACGATAGTTTGAGGATGCTTGTCAATGCCCACTAATCCCGAGCCTT1923ATGTTACATGGTATCTATGAGTTTGTCATTATAGTGCATTATGCATTTGTACTCCGTACG1983AGAATGAATCAGCGGCCGC2002(2) INFORMATION FOR SEQ ID NO: 4:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 557 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(vi) ORIGINAL SOURCE:(A) ORGANISM: Aspergillus Niger(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 4:MetArgValLeuProAlaAlaMetLeuValGlyAlaGlyThrAlaAla151015ValProProPheGlnGlnValLeuGlyGlyAsnGlyAlaLysHisGly202530AlaAspHisAlaAlaGluValProAlaAspHisSerAlaAspGlyPhe354045SerLysProLeuHisAlaPheGlnGluGluLeuLysSerLeuSerAsp505560GluAlaArgLysLeuTrpAspGluValAlaSerPhePheProGluSer65707580MetAspGlnAsnProLeuPheSerLeuProLysLysHisAsnArgArg859095ProAspHisHisTrpAspHisIleValArgGlySerAspValGlnSer100105110ValTrpValThrGlyGluAsnGlyGluLysGluArgGluValAspGly115120125LysLeuGluAlaTyrAspLeuArgValLysLysThrAspProSerSer130135140LeuGlyIleAspProGlyValLysGlnTyrThrGlyTyrLeuAspAsp145150155160AsnGluAsnAspLysHisLeuPheTyrTrpPhePheGluSerArgAsn165170175AspProGluAsnAspProValValLeuTrpLeuAsnGlyGlyProGly180185190CysSerSerLeuThrGlyLeuPheMetGluLeuGlyProSerSerIle195200205AsnLysLysIleGlnProValTyrAsnAspTyrAlaTrpAsnSerAsn210215220AlaSerValIlePheLeuAspGlnProValAsnValGlyTyrSerTyr225230235240SerAsnSerAlaValSerAspThrValAlaAlaGlyLysAspValTyr245250255AlaLeuLeuThrLeuPhePheLysGlnPheProGluTyrAlaLysGln260265270AspPheHisIleAlaGlyGluSerTyrAlaGlyHisTyrIleProVal275280285PheAlaSerGluIleLeuSerHisLysLysArgAsnIleAsnLeuGln290295300SerValLeuIleGlyAsnGlyLeuThrAspGlyLeuThrGlnTyrGlu305310315320TyrTyrArgProMetAlaCysGlyAspGlyGlyTyrProAlaValLeu325330335AspGluGlySerCysGlnAlaMetAspAsnAlaLeuProArgCysGln340345350SerMetIleGluSerCysTyrSerSerGluSerAlaTrpValCysVal355360365ProAlaSerIleTyrCysAsnAsnAlaLeuLeuAlaProTyrGlnArg370375380ThrGlyGlnAsnValTyrAspValArgGlyLysCysGluAspSerSer385390395400AsnLeuCysTyrSerAlaMetGlyTyrValSerAspTyrLeuAsnLys405410415ThrGluValIleGluAlaValGlyAlaGluValAsnGlyTyrAspSer420425430CysAsnPheAspIleAsnArgAsnPheLeuPheHisGlyAspTrpMet435440445LysProTyrHisArgLeuValProGlyLeuLeuGluGlnIleProVal450455460LeuIleTyrAlaGlyAspAlaAspPheIleCysAsnTrpLeuGlyAsn465470475480LysAlaTrpThrGluAlaLeuGluTrpProGlyGlnAlaGluTyrAla485490495SerAlaLysLeuGluAspLeuValValValGluAsnGluHisLysGly500505510LysLysIleGlyGlnValLysSerHisGlyAsnPheThrPheMetArg515520525LeuTyrGlyGlyGlyHisMetValProMetAspGlnProGluSerSer530535540LeuGluPhePheAsnArgTrpLeuGlyGlyGluTrpPhe545550555__________________________________________________________________________" ]
TECHNICAL FIELD The invention relates to handling session information for use on a Web, and more particularly to a method of inheriting the session information when a browser side is cooperatively directed from an original server site to another site and then restored to the original site. BACKGROUND OF THE INVENTION In recent years, along with the spread of businesses using the Web (World Wide Web) technologies, some applications have been developed in the form in which a plurality of Web sites provide cooperative services. For example, there is a scenario in which a user moves from a Web site of an insurance company to a site of a bank where the user receives a loan on security of one's insurance to make a payment, and then returns to the Web site of the insurance company again to continue the operation. In a great number of application scenarios, when the user moves from site A to site B and then returns to site A (assumed A′), it is necessary that the session information be inherited from A to A′. Usually, the session information is stored in a memory or database on the server side, and a server application can access the session information for each user with the session ID transmitted from the browser as a key. The session ID is transmitted from the server to the browser in establishing a first session, and held as a cookie on the browser side. However, in a Web application system constructed in combination with a load balancing server and an authentication server for a Single-Sign On (enabling all the permissible functions for a server or directory having the access right by making the user authentication once), there are some cases where the above session inheriting scheme may not operate. FIG. 6 is a diagram showing an exemplary configuration in which this problem may possibly occur. In an example of FIG. 6 , a self-company site (site A) 201 , the other company site (site B) 211 , and a browser 221 are connected via the Internet 231 . In this self company site 201 , an authentication server 202 of reverse proxy type (controlling all the accesses via a proxy server for security purposes) and a load balancing server 203 are combined, in which a first Web application server 204 and a second Web application server 205 are shown as the application servers allocated to the load balancing server 203 . It is assumed here that the authentication server 202 that accepts a request through the Internet 231 has an IP address of 9.100.1.1, and the first Web application server 204 and the second Web application server 205 that perform the actual processes have the IP addresses 192.168.0.1 and 192.168.0.2, respectively. The load balancing server 203 dispatches any one of three cluster addresses (virtual addresses accepted by the load balancing server 203 ) 192.168.1.0, 192.168.1.1 and 192.168.1.2 in accordance with the predetermined rules. FIG. 7 is a table for listing rules of dispatching each cluster address. Herein, the virtual cluster address 192.168.1.0 is dispatched to real address 192.168.0.1 and 192.168.0.2 uniformly for every HTTP request as a rule. Also, the virtual cluster address 192.168.1.1 is dispatched to 192.168.0.1 as a rule, or to 192.168.0.2 when it is determined that the real address 192.168.0.1 is down. Moreover, the virtual cluster address 192.168.1.2 is dispatched to 192.168.0.2 as a rule, or to 192.168.0.1 when it is determined that the real address 192.168.0.2 is down. The address 9.100.1.1 of authentication server 202 is a public IP address. By pre-negotiation, or any desirable means, browser 211 also knows the URLs 9.100.1.1/cluster0, 9.100.1.1/cluster1 and 9.100.1.1/cluster2. These URLs are translated to site A's internal IP addresses 192.168.1.0, 192.168.1.1 and 192.168.1.2, respectively by the authentication server (reverse-proxy). And then requests to these internal addresses are all handled by the load balancer and dispatched to the back-end Web servers 192.168.0.1 or 192.168.0.2 as dispatching rules of each internal address. The URL 9.100.1.1/cluster0 is used for initial load-balancing, and requests to that URL are dispatched to Web servers 192.168.0.1 or 192.168.0.2 as load balancing suggests. The URLs 9.100.1.1/cluster1 and 9.100.1.1/cluster2 are used to fix the target Web server to maintain “sticky” sessions, and they directly access Web server 192.168.0.1 and 192.168.0.2, respectively (except when the target server is down). The URLs 9.100.1.1/cluster1 and 9.100.1.1/cluster2 are returned to the client in the form of an embedded URL link by the Web server that handled the client's first request and established the session. Whether a client uses cluster1 or cluster2 depends on which Web server handled the client's first request. A first request to a Web application server is transmitted from authentication server 202 via the cluster address 192.168.1.0, and dispatched to the real address 192.168.0.1 or 192.168.0.2 by load balancer 203 . With a function of an HTTP server on the Web application server side, the request dispatched to the real address 192.168.0.1 is redirected to the cluster address 192.168.1.1 and the request dispatched to the real address 192.168.0.2 is redirected to the cluster address 192.168.1.2 (the response is once returned to the browser side and the request is automatically transmitted to the server side again). The “redirect” means that a HTTP server returns a response containing a Location response-header (defined in HTTP specification RFC2068) to a client, and the client automatically transmits a request according to the description of the Location response-header. The authentication server 202 accepts the requests which from a client at the three cluster addresses by making a conversion as shown in FIG. 8 . This conversion is totally performed for the request URL from the browser 221 and the URL described in the HTML of the response. For example, in a case where there is a description of “/index.html” in an anchor tag in the response HTML, the cluster address might be converted into “/cluster1/index.html” and delivered to the browser 221 . By performing this processing, an HTTP request from a certain user is dispatched into either the first Web application server 204 or the second Web application server 205 at a uniform probability at first. Since then, it is assured that the request from that user is dispatched (offset) to the same server, whereby the session information can be inherited while making load balancing. There is a method of identifying the user and dispatching or offsetting, using the IP address on the browser side, but this method is not effective in the case where a proxy like the authentication server 202 is placed at the front end with the configuration as shown in FIG. 6 . In these cases, the source IP address of all incoming packets is the address of the proxy, not the original client. The load balancing server 203 regards all the requests as arriving directly from the authentication server 202 , the user can not be distinguished. Under the above environment, it is supposed that the user is piloted from site A of the self company site 201 to site B of the other company site 211 and back to site A′ of the self company site 201 again. To pilot the user from site B to site A′, it is necessary that the URL information for linking to site A′ is described in the response HTML file from site B. It is common practice that the stationary URL (9.100.1.1/cluster0) of site A is informed in advance to site B 211 in cooperative relation to have it embedded in the HTML. However, when the offset (the “offset” means that the request addresses from a client are fixed to either of 9.100.1.1/cluster1 or 9.100.1.1/cluster2, once after the first request is sent to 9.100.1.1/cluster0) is firstly made at site A, a cookie is created in connection with the Path information “/cluster1” or “/cluster2” and sent to the browser 221 in a response, and as for the requests to the URL with the Path information unmatched (a cookie created at a request to 9.100.1.1/cluster1□□is not sent to the server when a client send a request to 9.100.1.1/cluster2), the session ID is not sent to the server side (self company site 201 ) for security reasons. The “security reasons” is to avoid sending a cookie carelessly. Supposing that the user interacts with site A using an address 9.100.1.1/cluster1 and then makes a request to site A′ at 9.100.1.1/cluster0 after moving to site B, the server application can not access the previous session information, even if this request is sent to the same Web application server as processed at site A. This is because the browser 221 determines that 9.100.1.1/cluster0 and 9.100.1.1/cluster1 are different transmission destinations, and does not transmit the cookie (session ID) employed in transactions with 9.100.1.1/cluster1 to the server side. This problem occurs in combination of: Authentication server method and security policy to be set up there Load balancing method and configuration Application scenario transferring from self site to other site to self site. Though there is a technical configuration of authentication or load balancing in which this problem does not occur, the authentication or load balancing method is constrained by many other conditions (security policy of the entire company, performance request, specifications of other company products) before examining the adaptability with the individual application scenarios. There is a method of inheriting the file or data stored in the database on the Web application server side with the user ID as a key, but the individual packaging is required for each application. The present invention has been achieved to solve the above-mentioned technical problems, and it is an object of the invention to provide a systematic method of solving a problem of inheriting the session information on the application server side when there are other sites interposed. SUMMARY OF THE INVENTION To attain the above object, the present invention, apart from an application (real application) for performing the actual processing, a first redirect application for accepting a first request for session and a second redirect application for accepting a request in getting back from an other site. The first redirect application and the second redirect application make a redirect process of returning a response to the browser side once, and automatically transmitting a request to the server side again, and return a response to the browser side. The browser side automatically transmits a request to the real application on the server side again, in accordance with a description in the response, without making the user aware of it. This invention enables the session information to be inherited by changing the cluster address in initiating the real application. Also, this invention has a feature of recording the cluster information (which cluster address is offset) required in getting back from the other site when firstly offsetting the session (before starting the session of the real application). That is, the invention provides a method of inheriting the session information that is effective when a browser side is once piloted from a self site ( FIG. 1 , 10 ) using a load balancing server to another site ( FIG. 1 , 11 ), and back to the self site again, including a step of generating a redirect response by setting a cluster address to be redirected on the basis of the result of dispatching by the load balancing server, a step of setting the cluster information indicating the cluster address offset in an identification information file of the browser side, a step of transmitting the redirect response, a step of receiving a request for the cluster address from the browser side to execute a real application, a step of receiving a request containing the identification information file from the browser side piloted from the other site to the self site, a step of acquiring the cluster information contained in the received identification information file, a step of recognizing which cluster address is offset upon the previous request to the self site on the basis of the acquired cluster information, a step of describing the recognized cluster address in the redirect response, and a step of transmitting the redirect response with the cluster address described to the browser side. The “set in an identification information file” as used herein includes the forms set on the memory. The same applies in the following. Also, the invention provides a method of inheriting the session information, including a step of receiving an HTTP request, a step of reading the cluster information to be redirected from a configuration file of an operating server, a step of generating a redirect response for initiating the real application employing the parameters received upon the HTTP request and the cluster information, a step of setting the cluster information as a cookie in the redirect response, a step of transmitting the redirect response to the browser side, a step of receiving a new HTTP request from the browser side piloted from the other site, a step of acquiring the cluster information that is set in the new HTTP request, a step of generating a new redirect response employing the parameters received upon the new HTTP request and the acquired cluster information, and a step of transmitting the new redirect response to the browser side. Moreover, the invention provides a method of inheriting the session information, including a step of checking whether or not the cluster information is embedded in a cookie for a received HTTP request, a step of generating a redirect response employing the cluster information, if the cluster information is embedded, or generating a redirect response employing the read cluster information read from a configuration file, if the cluster information is not embedded, a step of setting the cluster information or the read cluster information as the cookie in the redirect response, and a step of transmitting the redirect response. When the functions of the first redirect application and the second redirect application are implemented by a single redirect application, the session information can be inherited by performing the above steps. On one hand, the invention provides an application server comprising a real application for processing a received HTTP request and returning a response, a first redirect application for generating a redirect response on the basis of the cluster information based on the first dispatching, and transmitting the redirect response by setting the cluster information in a cookie of the browser, the first redirect application being initiated prior to execution of the real application upon the dispatched HTTP request, and a second redirect application for receiving from the browser the cluster information which the first redirect application has set in the cookie, generating a redirect response on the basis of the cluster information and transmitting the generated redirect response, the second redirect application being initiated prior to execution of the real application. Form a different viewpoint, the invention provides an application server comprising execution means for executing an actual application process upon a dispatched request, a first redirect processing means for performing a redirect processing by accepting a first request for session and returning a redirect response to the browser side, prior to execution of the execution means, and a second redirect processing means for performing a redirect process upon a request when the browser side is restored from the other site, and returning a redirect response to the browser side, prior to execution of the execution means. Also, the invention provides an application server comprising execution means for executing a real application upon a dispatched request, redirect processing means for executing a redirect response on the server side, prior to execution of the execution means, to change the cluster address in initiating the real application to enable the session information to be inherited, recording means for recording the cluster information (e.g., information indicating which cluster address is offset when firstly offsetting the session) required in being restored from the other site, when firstly offsetting the session before starting the session for the real application. On the other hand, the invention provides a Web site comprising an authentication server for making the authentication for a request from the browser, a load balancing server for dispatching the request via the authentication server, and a plurality of application servers provided to process the request dispatched by the load balancing server, wherein the application server comprises a real application for executing an application actually, a first redirect application for accepting a first request dispatched, and a second redirect application for accepting a request when the browser is restored from the other site, and wherein the first redirect application and the second redirect application perform a redirect processing before executing the real application to return a redirect response to the request to the browser. Each of the above inventions can be grasped as a program for enabling a computer operable as an application server to implement the functions. The program may be provided in a storage medium storing the program in a computer readable form. The storage medium may be a floppy disk or a CD-ROM medium, for example, in which the program is read by a floppy disk drive or a CD-ROM reader, stored in a flash ROM and run. Also, the program may be provided via a network by a program transmission apparatus. This program transmission apparatus is provided in the server on the host side, for example, and comprises a memory for storing the program, and program transmitting means for transmitting the program via the network. Moreover, when the computer is provided to the customer, the program may be installed in a storage device. As described above, with this invention, the problem of inheriting the session information when other sites are interposed can be solved. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an overall configuration of a network system according to an embodiment of the present invention; FIG. 2 is a diagram showing an operation of a redirect application (redirect application A) in response to a first request for a session and the corresponding operation of a browser; FIG. 3 is a diagram showing an operation of a redirect application (redirect application B) in response to a request in being restored from the other site and the corresponding operation of the browser; FIGS. 4A and 4B are flowcharts showing the processes that are performed in the redirect application; FIG. 5 is a flowchart showing an automatic determination process for determining whether the redirect application A or the redirect application B is run in the redirect application; FIG. 6 is a diagram showing a configuration example in which there is the possibility that a scheme for inheriting the session may not function; FIG. 7 is a table for listing rules of dispatching each cluster address; and FIG. 8 is a table for listing a relationship between an internal cluster address and the cluster address as seen from the browser side. DETAILED DESCRIPTION The preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing an overall configuration of a network system according to an embodiment of the present invention. The network system of FIG. 1 comprises a self site 10 for performing an application, another site 11 to be accessed by introducing a user from the self site 10 as an application scenario of this network system, and a browser 12 that is the user side software for gaining access to the self site 10 or the other site 11 via a network 13 . The application scenario of this embodiment involves a situation in which the user (browser 12 ) is once piloted from the self site 10 to the other site 11 , and back to the self site 10 again. Another scenario involves a situation in which a plurality of sites like the other site 11 are interposed while the browser 12 is restored to the self site 10 . The self site 10 comprises an authentication server 21 for making the authentication by collectively managing the name or password of the user who makes access to the self site 10 via the network 13 , a load balancing server 22 for performing a distribution process to balance the application load, that is, a dispatching process of selecting an application with the higher priority from among the applications in ready state and allocating the processing to the application, and a Web application server 23 for performing each application. The self site 10 is provided with a plurality of Web application servers 23 which are dispatched by the load balancing server 22 . In the example of FIG. 1 , the authentication server 21 presents only one IP address (9.100.1.1) to the outside. The load balancing server 22 has three cluster addresses (192.168.1.0, 192.168.1.1, 192.168.1.2) as the cluster address that is the virtual accepting address. The number of cluster addresses is increased when the number of Web application servers 23 is greater. The cluster addresses as seen from the side of the browser 12 are the same as shown in FIG. 8 . The cluster addresses 9.100.1.1/cluster0, 9.100.1.1/cluster1, and 9.100.1.1/cluster2 transmitted from the side of the browser 12 are converted into three internal cluster addresses 192.168.1.0, 192.168.1.1 and 192.168.1.2, respectively by the authentication server. Two Web application servers 23 as shown in FIG. 1 have the real addresses 192.168.0.1 and 192.168.0.2 assigned, for example, respectively. Each Web application server 23 comprises a real application 31 that is the application for performing the actual processing, and a redirect application 32 that is the application for making the processing called a redirect and once returning a response to the side of the browser 12 . This redirect application 32 is composed of a redirect application A (first redirect application) that is the application for accepting a first request for a session and a redirect application B (second redirect application) that is the application for accepting a request in being restored from the other site 11 . The browser 12 to which a response is returned by the redirect application 32 transmits a request to the real application 31 on the side of the server again in accordance with a description in the response automatically (without making the user aware of it). The redirect application A offsets a dispatching object by setting the cluster address based on the result of dispatching the first request in the session in a redirect response. At the same time, the information (cluster information) indicating which cluster address is offset is set in a cookie on the side of the browser 12 . The real application 31 is initiated via the offset cluster address so that the session ID for the real application 31 is set in the cookie on the side of the browser 12 . Thereafter, as long as the request is transmitted via this cluster address, the session ID in the cookie is transmitted to the server to enable the session information to be inherited. In the case where the browser is once piloted to the other site 11 and back to the self site 10 again, the other site 11 describes a link for initiating the redirect application B in the response HTML to be returned. The redirect application B receives the cluster information set in the cookie by the redirect application A from the browser 12 to know which cluster address is offset previously. The real application 31 can be initiated via this cluster address by having the cluster address described in the redirect response. The redirect application A records the information of the cluster address that is offset before transferring to the other site 11 . When being restored from the other site 11 , the redirect application B decides which cluster address is to be offset, employing this information, changes the cluster address and initiates the real application 31 . Thereby, the session information can be inherited in a transition from the self site 10 to the other site 11 to the self site 10 . It is known to use cookies to maintain a “stick” session to a server in a cluster after an initial step of selecting the server by load balancing. See, for example, U.S. Pat. No. 6,374,300; Method and system for storing load balancing information with an HTTP cookie. However, the method of this embodiment has the following features: Enabling the session information to be inherited by changing the cluster address in initiating the application through the redirect processing. Recording the cluster information (which cluster address is offset) required in being restored from the other site 11 at the first offset of the session (before the session of the real application 31 is started). Implementing the load balancing server 22 itself with a simple packaging for performing the processing on the IP layer. The cluster address means the IP address in a format of 192.168.0.1, for example. Also, the cluster information is the information for designating one of a plurality of cluster addresses. For example, the cluster information stored in the cookie to designate any one of three cluster addresses 192.168.0.1, 192.168.0.2 and 192.168.0.3. is one character taking the value of “A”, “B” or “C”. FIG. 2 is a diagram showing an operation of the redirect application 32 (redirect application A) in response to a first request for session and the corresponding operation of the browser 12 . In FIG. 2 , first of all, in {circumflex over (1)} Request to the cluster address 192.168.1.0, an HTTP request transmitted from the browser 12 to URL 9.100.1.1/cluster0 after the user authentication is converted into the cluster address 192.168.1.0 destination by the authentication server 21 and further distributed to the real address 192.168.0.1 or 192.168.0.2 by the load balancing server 22 . The HTTP request initiates the redirect application A in the redirect application 32 (servlet or program initiated from the servlet), but contains the information specifying the real application 31 (servlet or program initiated from the servlet) as its argument or the argument information needed by the logic of the real application 31 . The HTTP request of 1 is processed by the redirect application A on the Web application server 23 to which this request is actually dispatched to create {circumflex over (2)} a redirect response. The redirect process by the redirect application 32 can be implemented by a Location header of the HTTP, the HTML response describing in Meta tag, or the HTML response containing Java® Script automatically executed. In the response with the Location header, a special header as the Location header is set in a response header part in which the redirect application 32 returns the response. As the value of this header, the URL of the redirect destination is described, whereby the browser 12 having received the response makes automatically the redirect. In the response with Meta tag, the Meta tag with META HTTP-EQUIV=“Refresh” designated is described in a response body part (HTML) into which the redirect application 32 returns the response. The redirect destination URL is described with a CONTENT attribute as shown below. <META HTTP-EQUIV=“Refresh” CONTENT=“URL=http://xyz.com/”> Also, in the response with Java® Script, Java® Script to be executed immediately after displaying the browser screen is described in a response body part (HTML) into which the redirect application 32 returns the response. A description of jumping to the redirect destination URL is embedded in Java® Script. With this method, the redirect is enabled. In the processing {circumflex over (2)} as shown in FIG. 2 , the redirect application A reads the cluster information (cluster address at which the application itself is initiated) described in the configuration file for each Web application server 23 , and embeds the cluster address for the real application 31 in the redirect response. The arguments necessary for the logic of the real application 31 are also embedded directly in the redirect response. Also, the redirect application A sets the cluster information read from the configuration file as a cookie in a Set-Cookie header within the header of the redirect response. In a process where the redirect response is returned via the authentication server 21 to the browser 12 , the Path attribute in the Set-Cookie is changed, and the information indicating a request-time cluster such as “/cluster0” is added. (This means that Path attribute in Set-Cookie response header is changed from “/” to “/cluster0”.) The Path attribute is the information used for privacy protection on the side of the browser 12 . For example, the cookie having the Path attribute “cluster0” is only appended to the request in the format of 9.100.1.1/cluster0/ . . . . In {circumflex over (3)} Request to the cluster address 192.168.1.1 or 192.168.1.2 (once the first request is dispatched to either 1.1 or 1.2, later request should be sent to the same address) as shown in FIG. 2 , the HTTP request is automatically transmitted to the real application 31 by the browser 12 having received the redirect response, in accordance with the contents of the response. Owing to the offset by the redirect application A, the transmission destination (URL) of the request is 9.100.1.1/cluster1/ . . . or 9.100.1.1/cluster2/ . . . . The destination address is converted into the cluster address 192.168.1.1 or 192.168.1.2 by the authentication server 21 , and then dispatched to the real address 192.168.0.1 or 192.168.0.2 by the load balancing server 22 . At the same time, in the browser 12 , the content (value or attribute) of the cookie transmitted in {circumflex over (2)} of FIG. 2 is saved in the memory or file on the client side. In {circumflex over (4)} Response with processed result as shown in FIG. 2 , it is unnecessary to change the real application 31 . The real application 31 processes the received HTTP request and returns a conventional response. The information inherited to the next HTTP request process is set by creating a session object, as needed. The session ID for identifying the session object is created by the Web application server 23 and set in the Set-Cookie header of the header in the response with processed result. The Path attribute (“/cluster1” or “/cluster2” depending on via which cluster address the real application 31 is initiated) is added to this cookie by the authentication server 21 . The cookie of the session ID is saved at the browser 12 having received the resultant response. Since then, this session ID is appended to the request transmitted to the same cluster address (address with the Path attribute of cookie matched), whereby the server program can gain access to the session information continually. FIG. 3 is a diagram showing an operation of the redirect application 32 (redirect application B) in response to a request in being restored from the other site 11 and the corresponding operation of the browser 12 . After the operation {circumflex over (4)} as shown in FIG. 2 , there are repetitive requests and responses between the self site 10 and the browser 12 . Thereafter, the HTTP request is transmitted to the other site 11 , followed by repetitive requests and responses to and from the other site 11 , in which the request transmitted to the self site 10 through the link in the HTML received from the other site 11 corresponds to {circumflex over (5)} as shown in FIG. 3 . In {circumflex over (5)} Request to the cluster address 192.168.1.0 the HTTP request transmitted to URL9.100.1.1/cluster0 designated from the other site 11 is converted into the cluster address 192.168.1.0 destination by the authentication server 21 , and further distributed to the real address 192.168.0.1 or 192.168.0.2 by the load balancing server 22 . The HTTP request initiates the redirect application B, but contains, as its arguments, the information specifying the real application 31 or the argument information required by the logic of the real application 31 . This request has a path part “/cluster0”, whereby the information of the session ID set in the cookie in {circumflex over (4)} of FIG. 2 is not transmitted from the browser 12 . Namely, the redirect application B can not gain access to the session information which is operative in the self site 10 previously. However, because the cookie of the cluster information transmitted in {circumflex over (2)} of FIG. 2 has the matched Path attribute, the cluster information is set in the request header and transmitted to the server side. The redirect application B can know via which cluster address the real application 31 should be initiated to gain access to the previous session information. The HTTP request of {circumflex over (5)} is processed by the redirect application B on the Web application server 23 to which the request is actually dispatched to create the {circumflex over (6)} redirect response. The redirect application B embeds the cluster address of the real application 31 in the redirect response, employing the cluster information read from the received request header. The arguments required for the logic of the real application 31 are also embedded directly into the redirect response. The browser 12 having received the redirect response transmits automatically the HTTP request to the real application 31 in accordance with the contents of the response. The transmission destination cluster address of the request is the same with the request in {circumflex over (7)} cluster address 192.168.1.1 or 192.168.1.2 as at the time of request in {circumflex over (3)}. Because the Path information is matched with the Path attribute of the cookie set in {circumflex over (4)} of FIG. 2 , the session ID is set in the request header and transmitted to the server side. In {circumflex over (8)} Reply with processed result in FIG. 3 , the real application 31 makes access to the session object with the received session ID as a key, and after execution of an affair logic, returns the result to the browser 12 . Then, the processing in the redirect application 32 will be described below. FIGS. 4A and 4B are flowcharts showing processes to be executed in the redirect application 32 . FIG. 4A shows a process for the redirect application A and FIG. 4B shows a process for the redirect application B. As shown in FIG. 4A , first of all, the redirect application A having received the HTTP request extracts and saves the associated parameters (step 101 ). Then, the information of the cluster address to be redirected is read from the configuration file of each Web application server 23 on which the redirect application 32 is operating (step 102 ). Then, the redirect application A creates a redirect response for initiating the real application 31 , employing the information of the parameters and the cluster address received upon the HTTP request (step 103 ). Thereafter, a Set-Cookie header is set in the header part of the HTTP response, and the cluster information is embedded into the cookie (step 104 ). And the redirect response that is prepared as the HTTP response is transmitted to the browser 12 (step 105 ), and the process of the redirect application A is ended. In the process of the redirect application B, first of all, the HTTP request is received, and the associated parameters are extracted and saved (step 111 ). Then, the information of the cluster address is acquired from the cookie set in the header part of the received HTTP request (step 112 ). Then, a redirect response for initiating the real application 31 is created, employing the information of the parameters and the cluster address received upon the HTTP request (step 113 ). And the redirect response that is prepared as the HTTP response is transmitted to the browser 12 (step 114 ), and the process of the redirect application B is ended. In this manner, in this embodiment, the cluster address of the real application 31 is embedded in the redirect response on the server side, whereby the browser 12 having received the response can make the redirect for automatically transmitting the request to this cluster address. More specifically, this “embedding” means that the cluster address is described in the HTTP header such as Java® Script or Location. Also, the cluster information as a cookie is set in the Set-Cookie header of the header for the redirect response on the server side, whereby the browser 12 having received the response stores this cluster information as a cookie in a memory or disk within the personal computer (PC). Since then, when the request is transmitted to the server, the browser 12 appends the stored cluster information as a part of the request data. FIG. 5 is a flowchart showing an automatic determination process for determining whether the redirect application A or the redirect application B is run in the redirect application 32 . First of all, an HTTP request is received, and the associated parameters are extracted and saved (step 151 ). Then, it is checked whether or not the cluster information as a cookie is embedded into the header part of the received HTTP request (step 152 ). If it is embedded, the cluster information from the header is acquired, and the information is employed as the cluster address (step 153 ). When it is not embedded as the cookie, the information of the cluster address is read from the configuration file of the server (step 154 ). Using the information of the cluster address obtained in this way, a redirect response for initiating the real application 31 is created (step 155 ). Herein, it is determined whether or not the cookie indicating the cluster information is set in the header part of the received HTTP request (step 156 ). When it is not set, the information is set as a cookie in the header part of the response (step 157 ), and the HTTP response is transmitted to the browser 12 (step 158 ). Thereby, the process is ended. With this embodiment, in a system configuration using a combination of the authentication server 21 and the load balancing server 22 on an IP layer basis, the session information can be inherited in a transition from the self site 10 to the other site 11 to the self site 10 . Also, in a system configuration using the authentication server 21 of the reverse proxy type, an application scenario in which the browser is moved from the self site 10 to the other site 11 , and moved back to the self site 10 again, is expected to increase in the future, along with the higher and more complex Web application. Also, in the Web site of the company, the use of the load balancing server 22 is indispensable from the viewpoint of reliability or scalability. Accordingly, it is considered that the problem of inheriting the session information will often arise in the future, and this embodiment to solve this problem is very valuable. As a cooperative scenario between the Web sites (self site 10 and other site 11 ) according to this embodiment, for example, it is conceived that the user moves from a Web site (self site 10 ) of an insurance company to a bank site (other site) where the user makes a loan on security of one's insurance to make a payment, and gets back to the Web site (self site 10 ) of the insurance company again to continue the operation. In such scenario, even if the user once moves to the bank site (other site 11 ), and then transfers to the Web site (self site 10 ) of the insurance company, the insurance contract operation can be continued. For example, there is a scenario where after a commodity is put in a shopping bag at a site (self site 10 ) in the shopping mall, the user transfers to another site (other site 11 ) of a credit company to confirm a schedule of withdrawal, and then is restored to the site (self site 10 ) in the shopping mall to carry out a purchase procedure. At this time, with this embodiment, in a system configuration in which the site (self site 10 ) of the shopping mall employs a combination of the authentication server 21 and the load balancing server 22 on an IP layer basis, the session information is enabled to be inherited when being restored from the other site 11 to the site (self site 10 ) in the shopping mall, whereby the operation can be smoothly continued even after transiting through a plurality of sites. Moreover, another scenario is applicable in which when making a reservation of the travel, the user moves to the site (other site 11 ) relevant with the hotels or inns halfway on the procedure of the site (self site 10 ) for making reservations of the transport facilities to make sure of the reservation, and then decides finally the reservation of the transport facilities at site (self site 10 ) for making reservations of the transport facilities. Then, with this embodiment, in a system configuration having a load balancing function at site (self site 10 ) for making reservations of the transport facilities, the session information is enabled to be inherited even in the case of transiting to the self site 10 after transferring to the other site 11 related with the reservation of the travel, whereby the reservation operation at site (self site 10 ) for making reservations of the transport facilities can be continued.
A method is disclosed to maintain session continuity between a browser and an initial server in a cluster when the browser is transferred from the initial server to a different server and returned thereafter to the original server.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "TECHNICAL FIELD The invention relates to handling session information for use on a Web, and more particularly to a method of inheriting the session information when a browser side is cooperatively directed from an original server site to another site and then restored to the original site.", "BACKGROUND OF THE INVENTION In recent years, along with the spread of businesses using the Web (World Wide Web) technologies, some applications have been developed in the form in which a plurality of Web sites provide cooperative services.", "For example, there is a scenario in which a user moves from a Web site of an insurance company to a site of a bank where the user receives a loan on security of one's insurance to make a payment, and then returns to the Web site of the insurance company again to continue the operation.", "In a great number of application scenarios, when the user moves from site A to site B and then returns to site A (assumed A′), it is necessary that the session information be inherited from A to A′.", "Usually, the session information is stored in a memory or database on the server side, and a server application can access the session information for each user with the session ID transmitted from the browser as a key.", "The session ID is transmitted from the server to the browser in establishing a first session, and held as a cookie on the browser side.", "However, in a Web application system constructed in combination with a load balancing server and an authentication server for a Single-Sign On (enabling all the permissible functions for a server or directory having the access right by making the user authentication once), there are some cases where the above session inheriting scheme may not operate.", "FIG. 6 is a diagram showing an exemplary configuration in which this problem may possibly occur.", "In an example of FIG. 6 , a self-company site (site A) 201 , the other company site (site B) 211 , and a browser 221 are connected via the Internet 231 .", "In this self company site 201 , an authentication server 202 of reverse proxy type (controlling all the accesses via a proxy server for security purposes) and a load balancing server 203 are combined, in which a first Web application server 204 and a second Web application server 205 are shown as the application servers allocated to the load balancing server 203 .", "It is assumed here that the authentication server 202 that accepts a request through the Internet 231 has an IP address of 9.100.1[.", "].1, and the first Web application server 204 and the second Web application server 205 that perform the actual processes have the IP addresses 192.168.0[.", "].1 and 192.168.0[.", "].2, respectively.", "The load balancing server 203 dispatches any one of three cluster addresses (virtual addresses accepted by the load balancing server 203 ) 192.168.1[.", "].0, 192.168.1[.", "].1 and 192.168.1[.", "].2 in accordance with the predetermined rules.", "FIG. 7 is a table for listing rules of dispatching each cluster address.", "Herein, the virtual cluster address 192.168.1[.", "].0 is dispatched to real address 192.168.0[.", "].1 and 192.168.0[.", "].2 uniformly for every HTTP request as a rule.", "Also, the virtual cluster address 192.168.1[.", "].1 is dispatched to 192.168.0[.", "].1 as a rule, or to 192.168.0[.", "].2 when it is determined that the real address 192.168.0[.", "].1 is down.", "Moreover, the virtual cluster address 192.168.1[.", "].2 is dispatched to 192.168.0[.", "].2 as a rule, or to 192.168.0[.", "].1 when it is determined that the real address 192.168.0[.", "].2 is down.", "The address 9.100.1[.", "].1 of authentication server 202 is a public IP address.", "By pre-negotiation, or any desirable means, browser 211 also knows the URLs 9.100.1[.", "].1/cluster0, 9.100.1[.", "].1/cluster1 and 9.100.1[.", "].1/cluster2.", "These URLs are translated to site A's internal IP addresses 192.168.1[.", "].0, 192.168.1[.", "].1 and 192.168.1[.", "].2, respectively by the authentication server (reverse-proxy).", "And then requests to these internal addresses are all handled by the load balancer and dispatched to the back-end Web servers 192.168.0[.", "].1 or 192.168.0[.", "].2 as dispatching rules of each internal address.", "The URL 9.100.1[.", "].1/cluster0 is used for initial load-balancing, and requests to that URL are dispatched to Web servers 192.168.0[.", "].1 or 192.168.0[.", "].2 as load balancing suggests.", "The URLs 9.100.1[.", "].1/cluster1 and 9.100.1[.", "].1/cluster2 are used to fix the target Web server to maintain “sticky”", "sessions, and they directly access Web server 192.168.0[.", "].1 and 192.168.0[.", "].2, respectively (except when the target server is down).", "The URLs 9.100.1[.", "].1/cluster1 and 9.100.1[.", "].1/cluster2 are returned to the client in the form of an embedded URL link by the Web server that handled the client's first request and established the session.", "Whether a client uses cluster1 or cluster2 depends on which Web server handled the client's first request.", "A first request to a Web application server is transmitted from authentication server 202 via the cluster address 192.168.1[.", "].0, and dispatched to the real address 192.168.0[.", "].1 or 192.168.0[.", "].2 by load balancer 203 .", "With a function of an HTTP server on the Web application server side, the request dispatched to the real address 192.168.0[.", "].1 is redirected to the cluster address 192.168.1[.", "].1 and the request dispatched to the real address 192.168.0[.", "].2 is redirected to the cluster address 192.168.1[.", "].2 (the response is once returned to the browser side and the request is automatically transmitted to the server side again).", "The “redirect”", "means that a HTTP server returns a response containing a Location response-header (defined in HTTP specification RFC2068) to a client, and the client automatically transmits a request according to the description of the Location response-header.", "The authentication server 202 accepts the requests which from a client at the three cluster addresses by making a conversion as shown in FIG. 8 .", "This conversion is totally performed for the request URL from the browser 221 and the URL described in the HTML of the response.", "For example, in a case where there is a description of “/index.html”", "in an anchor tag in the response HTML, the cluster address might be converted into “/cluster1/index.html”", "and delivered to the browser 221 .", "By performing this processing, an HTTP request from a certain user is dispatched into either the first Web application server 204 or the second Web application server 205 at a uniform probability at first.", "Since then, it is assured that the request from that user is dispatched (offset) to the same server, whereby the session information can be inherited while making load balancing.", "There is a method of identifying the user and dispatching or offsetting, using the IP address on the browser side, but this method is not effective in the case where a proxy like the authentication server 202 is placed at the front end with the configuration as shown in FIG. 6 .", "In these cases, the source IP address of all incoming packets is the address of the proxy, not the original client.", "The load balancing server 203 regards all the requests as arriving directly from the authentication server 202 , the user can not be distinguished.", "Under the above environment, it is supposed that the user is piloted from site A of the self company site 201 to site B of the other company site 211 and back to site A′ of the self company site 201 again.", "To pilot the user from site B to site A′, it is necessary that the URL information for linking to site A′ is described in the response HTML file from site B. It is common practice that the stationary URL (9.100.1[.", "].1/cluster0) of site A is informed in advance to site B 211 in cooperative relation to have it embedded in the HTML.", "However, when the offset (the “offset”", "means that the request addresses from a client are fixed to either of 9.100.1[.", "].1/cluster1 or 9.100.1[.", "].1/cluster2, once after the first request is sent to 9.100.1[.", "].1/cluster0) is firstly made at site A, a cookie is created in connection with the Path information “/cluster1”", "or “/cluster2”", "and sent to the browser 221 in a response, and as for the requests to the URL with the Path information unmatched (a cookie created at a request to 9.100.1[.", "].1/cluster1□□is not sent to the server when a client send a request to 9.100.1[.", "].1/cluster2), the session ID is not sent to the server side (self company site 201 ) for security reasons.", "The “security reasons”", "is to avoid sending a cookie carelessly.", "Supposing that the user interacts with site A using an address 9.100.1[.", "].1/cluster1 and then makes a request to site A′ at 9.100.1[.", "].1/cluster0 after moving to site B, the server application can not access the previous session information, even if this request is sent to the same Web application server as processed at site A. This is because the browser 221 determines that 9.100.1[.", "].1/cluster0 and 9.100.1[.", "].1/cluster1 are different transmission destinations, and does not transmit the cookie (session ID) employed in transactions with 9.100.1[.", "].1/cluster1 to the server side.", "This problem occurs in combination of: Authentication server method and security policy to be set up there Load balancing method and configuration Application scenario transferring from self site to other site to self site.", "Though there is a technical configuration of authentication or load balancing in which this problem does not occur, the authentication or load balancing method is constrained by many other conditions (security policy of the entire company, performance request, specifications of other company products) before examining the adaptability with the individual application scenarios.", "There is a method of inheriting the file or data stored in the database on the Web application server side with the user ID as a key, but the individual packaging is required for each application.", "The present invention has been achieved to solve the above-mentioned technical problems, and it is an object of the invention to provide a systematic method of solving a problem of inheriting the session information on the application server side when there are other sites interposed.", "SUMMARY OF THE INVENTION To attain the above object, the present invention, apart from an application (real application) for performing the actual processing, a first redirect application for accepting a first request for session and a second redirect application for accepting a request in getting back from an other site.", "The first redirect application and the second redirect application make a redirect process of returning a response to the browser side once, and automatically transmitting a request to the server side again, and return a response to the browser side.", "The browser side automatically transmits a request to the real application on the server side again, in accordance with a description in the response, without making the user aware of it.", "This invention enables the session information to be inherited by changing the cluster address in initiating the real application.", "Also, this invention has a feature of recording the cluster information (which cluster address is offset) required in getting back from the other site when firstly offsetting the session (before starting the session of the real application).", "That is, the invention provides a method of inheriting the session information that is effective when a browser side is once piloted from a self site ( FIG. 1 , 10 ) using a load balancing server to another site ( FIG. 1 , 11 ), and back to the self site again, including a step of generating a redirect response by setting a cluster address to be redirected on the basis of the result of dispatching by the load balancing server, a step of setting the cluster information indicating the cluster address offset in an identification information file of the browser side, a step of transmitting the redirect response, a step of receiving a request for the cluster address from the browser side to execute a real application, a step of receiving a request containing the identification information file from the browser side piloted from the other site to the self site, a step of acquiring the cluster information contained in the received identification information file, a step of recognizing which cluster address is offset upon the previous request to the self site on the basis of the acquired cluster information, a step of describing the recognized cluster address in the redirect response, and a step of transmitting the redirect response with the cluster address described to the browser side.", "The “set in an identification information file”", "as used herein includes the forms set on the memory.", "The same applies in the following.", "Also, the invention provides a method of inheriting the session information, including a step of receiving an HTTP request, a step of reading the cluster information to be redirected from a configuration file of an operating server, a step of generating a redirect response for initiating the real application employing the parameters received upon the HTTP request and the cluster information, a step of setting the cluster information as a cookie in the redirect response, a step of transmitting the redirect response to the browser side, a step of receiving a new HTTP request from the browser side piloted from the other site, a step of acquiring the cluster information that is set in the new HTTP request, a step of generating a new redirect response employing the parameters received upon the new HTTP request and the acquired cluster information, and a step of transmitting the new redirect response to the browser side.", "Moreover, the invention provides a method of inheriting the session information, including a step of checking whether or not the cluster information is embedded in a cookie for a received HTTP request, a step of generating a redirect response employing the cluster information, if the cluster information is embedded, or generating a redirect response employing the read cluster information read from a configuration file, if the cluster information is not embedded, a step of setting the cluster information or the read cluster information as the cookie in the redirect response, and a step of transmitting the redirect response.", "When the functions of the first redirect application and the second redirect application are implemented by a single redirect application, the session information can be inherited by performing the above steps.", "On one hand, the invention provides an application server comprising a real application for processing a received HTTP request and returning a response, a first redirect application for generating a redirect response on the basis of the cluster information based on the first dispatching, and transmitting the redirect response by setting the cluster information in a cookie of the browser, the first redirect application being initiated prior to execution of the real application upon the dispatched HTTP request, and a second redirect application for receiving from the browser the cluster information which the first redirect application has set in the cookie, generating a redirect response on the basis of the cluster information and transmitting the generated redirect response, the second redirect application being initiated prior to execution of the real application.", "Form a different viewpoint, the invention provides an application server comprising execution means for executing an actual application process upon a dispatched request, a first redirect processing means for performing a redirect processing by accepting a first request for session and returning a redirect response to the browser side, prior to execution of the execution means, and a second redirect processing means for performing a redirect process upon a request when the browser side is restored from the other site, and returning a redirect response to the browser side, prior to execution of the execution means.", "Also, the invention provides an application server comprising execution means for executing a real application upon a dispatched request, redirect processing means for executing a redirect response on the server side, prior to execution of the execution means, to change the cluster address in initiating the real application to enable the session information to be inherited, recording means for recording the cluster information (e.g., information indicating which cluster address is offset when firstly offsetting the session) required in being restored from the other site, when firstly offsetting the session before starting the session for the real application.", "On the other hand, the invention provides a Web site comprising an authentication server for making the authentication for a request from the browser, a load balancing server for dispatching the request via the authentication server, and a plurality of application servers provided to process the request dispatched by the load balancing server, wherein the application server comprises a real application for executing an application actually, a first redirect application for accepting a first request dispatched, and a second redirect application for accepting a request when the browser is restored from the other site, and wherein the first redirect application and the second redirect application perform a redirect processing before executing the real application to return a redirect response to the request to the browser.", "Each of the above inventions can be grasped as a program for enabling a computer operable as an application server to implement the functions.", "The program may be provided in a storage medium storing the program in a computer readable form.", "The storage medium may be a floppy disk or a CD-ROM medium, for example, in which the program is read by a floppy disk drive or a CD-ROM reader, stored in a flash ROM and run.", "Also, the program may be provided via a network by a program transmission apparatus.", "This program transmission apparatus is provided in the server on the host side, for example, and comprises a memory for storing the program, and program transmitting means for transmitting the program via the network.", "Moreover, when the computer is provided to the customer, the program may be installed in a storage device.", "As described above, with this invention, the problem of inheriting the session information when other sites are interposed can be solved.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an overall configuration of a network system according to an embodiment of the present invention;", "FIG. 2 is a diagram showing an operation of a redirect application (redirect application A) in response to a first request for a session and the corresponding operation of a browser;", "FIG. 3 is a diagram showing an operation of a redirect application (redirect application B) in response to a request in being restored from the other site and the corresponding operation of the browser;", "FIGS. 4A and 4B are flowcharts showing the processes that are performed in the redirect application;", "FIG. 5 is a flowchart showing an automatic determination process for determining whether the redirect application A or the redirect application B is run in the redirect application;", "FIG. 6 is a diagram showing a configuration example in which there is the possibility that a scheme for inheriting the session may not function;", "FIG. 7 is a table for listing rules of dispatching each cluster address;", "and FIG. 8 is a table for listing a relationship between an internal cluster address and the cluster address as seen from the browser side.", "DETAILED DESCRIPTION The preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.", "FIG. 1 is a block diagram showing an overall configuration of a network system according to an embodiment of the present invention.", "The network system of FIG. 1 comprises a self site 10 for performing an application, another site 11 to be accessed by introducing a user from the self site 10 as an application scenario of this network system, and a browser 12 that is the user side software for gaining access to the self site 10 or the other site 11 via a network 13 .", "The application scenario of this embodiment involves a situation in which the user (browser 12 ) is once piloted from the self site 10 to the other site 11 , and back to the self site 10 again.", "Another scenario involves a situation in which a plurality of sites like the other site 11 are interposed while the browser 12 is restored to the self site 10 .", "The self site 10 comprises an authentication server 21 for making the authentication by collectively managing the name or password of the user who makes access to the self site 10 via the network 13 , a load balancing server 22 for performing a distribution process to balance the application load, that is, a dispatching process of selecting an application with the higher priority from among the applications in ready state and allocating the processing to the application, and a Web application server 23 for performing each application.", "The self site 10 is provided with a plurality of Web application servers 23 which are dispatched by the load balancing server 22 .", "In the example of FIG. 1 , the authentication server 21 presents only one IP address (9.100.1[.", "].1) to the outside.", "The load balancing server 22 has three cluster addresses (192.168.1[.", "].0, 192.168.1[.", "].1, 192.168.1[.", "].2) as the cluster address that is the virtual accepting address.", "The number of cluster addresses is increased when the number of Web application servers 23 is greater.", "The cluster addresses as seen from the side of the browser 12 are the same as shown in FIG. 8 .", "The cluster addresses 9.100.1[.", "].1/cluster0, 9.100.1[.", "].1/cluster1, and 9.100.1[.", "].1/cluster2 transmitted from the side of the browser 12 are converted into three internal cluster addresses 192.168.1[.", "].0, 192.168.1[.", "].1 and 192.168.1[.", "].2, respectively by the authentication server.", "Two Web application servers 23 as shown in FIG. 1 have the real addresses 192.168.0[.", "].1 and 192.168.0[.", "].2 assigned, for example, respectively.", "Each Web application server 23 comprises a real application 31 that is the application for performing the actual processing, and a redirect application 32 that is the application for making the processing called a redirect and once returning a response to the side of the browser 12 .", "This redirect application 32 is composed of a redirect application A (first redirect application) that is the application for accepting a first request for a session and a redirect application B (second redirect application) that is the application for accepting a request in being restored from the other site 11 .", "The browser 12 to which a response is returned by the redirect application 32 transmits a request to the real application 31 on the side of the server again in accordance with a description in the response automatically (without making the user aware of it).", "The redirect application A offsets a dispatching object by setting the cluster address based on the result of dispatching the first request in the session in a redirect response.", "At the same time, the information (cluster information) indicating which cluster address is offset is set in a cookie on the side of the browser 12 .", "The real application 31 is initiated via the offset cluster address so that the session ID for the real application 31 is set in the cookie on the side of the browser 12 .", "Thereafter, as long as the request is transmitted via this cluster address, the session ID in the cookie is transmitted to the server to enable the session information to be inherited.", "In the case where the browser is once piloted to the other site 11 and back to the self site 10 again, the other site 11 describes a link for initiating the redirect application B in the response HTML to be returned.", "The redirect application B receives the cluster information set in the cookie by the redirect application A from the browser 12 to know which cluster address is offset previously.", "The real application 31 can be initiated via this cluster address by having the cluster address described in the redirect response.", "The redirect application A records the information of the cluster address that is offset before transferring to the other site 11 .", "When being restored from the other site 11 , the redirect application B decides which cluster address is to be offset, employing this information, changes the cluster address and initiates the real application 31 .", "Thereby, the session information can be inherited in a transition from the self site 10 to the other site 11 to the self site 10 .", "It is known to use cookies to maintain a “stick”", "session to a server in a cluster after an initial step of selecting the server by load balancing.", "See, for example, U.S. Pat. No. 6,374,300;", "Method and system for storing load balancing information with an HTTP cookie.", "However, the method of this embodiment has the following features: Enabling the session information to be inherited by changing the cluster address in initiating the application through the redirect processing.", "Recording the cluster information (which cluster address is offset) required in being restored from the other site 11 at the first offset of the session (before the session of the real application 31 is started).", "Implementing the load balancing server 22 itself with a simple packaging for performing the processing on the IP layer.", "The cluster address means the IP address in a format of 192.168.0[.", "].1, for example.", "Also, the cluster information is the information for designating one of a plurality of cluster addresses.", "For example, the cluster information stored in the cookie to designate any one of three cluster addresses 192.168.0[.", "].1, 192.168.0[.", "].2 and 192.168.0[.", "].3.", "is one character taking the value of “A”, “B”", "or “C.”", "FIG. 2 is a diagram showing an operation of the redirect application 32 (redirect application A) in response to a first request for session and the corresponding operation of the browser 12 .", "In FIG. 2 , first of all, in {circumflex over (1)} Request to the cluster address 192.168.1[.", "].0, an HTTP request transmitted from the browser 12 to URL 9.100.1[.", "].1/cluster0 after the user authentication is converted into the cluster address 192.168.1[.", "].0 destination by the authentication server 21 and further distributed to the real address 192.168.0[.", "].1 or 192.168.0[.", "].2 by the load balancing server 22 .", "The HTTP request initiates the redirect application A in the redirect application 32 (servlet or program initiated from the servlet), but contains the information specifying the real application 31 (servlet or program initiated from the servlet) as its argument or the argument information needed by the logic of the real application 31 .", "The HTTP request of 1 is processed by the redirect application A on the Web application server 23 to which this request is actually dispatched to create {circumflex over (2)} a redirect response.", "The redirect process by the redirect application 32 can be implemented by a Location header of the HTTP, the HTML response describing in Meta tag, or the HTML response containing Java® Script automatically executed.", "In the response with the Location header, a special header as the Location header is set in a response header part in which the redirect application 32 returns the response.", "As the value of this header, the URL of the redirect destination is described, whereby the browser 12 having received the response makes automatically the redirect.", "In the response with Meta tag, the Meta tag with META HTTP-EQUIV=“Refresh”", "designated is described in a response body part (HTML) into which the redirect application 32 returns the response.", "The redirect destination URL is described with a CONTENT attribute as shown below.", "<META HTTP-EQUIV=“Refresh”", "CONTENT=“URL=http://xyz.com/”>", "Also, in the response with Java® Script, Java® Script to be executed immediately after displaying the browser screen is described in a response body part (HTML) into which the redirect application 32 returns the response.", "A description of jumping to the redirect destination URL is embedded in Java® Script.", "With this method, the redirect is enabled.", "In the processing {circumflex over (2)} as shown in FIG. 2 , the redirect application A reads the cluster information (cluster address at which the application itself is initiated) described in the configuration file for each Web application server 23 , and embeds the cluster address for the real application 31 in the redirect response.", "The arguments necessary for the logic of the real application 31 are also embedded directly in the redirect response.", "Also, the redirect application A sets the cluster information read from the configuration file as a cookie in a Set-Cookie header within the header of the redirect response.", "In a process where the redirect response is returned via the authentication server 21 to the browser 12 , the Path attribute in the Set-Cookie is changed, and the information indicating a request-time cluster such as “/cluster0”", "is added.", "(This means that Path attribute in Set-Cookie response header is changed from “/”", "to “/cluster0”.) The Path attribute is the information used for privacy protection on the side of the browser 12 .", "For example, the cookie having the Path attribute “cluster0”", "is only appended to the request in the format of 9.100.1[.", "].1/cluster0/ .", "In {circumflex over (3)} Request to the cluster address 192.168.1[.", "].1 or 192.168.1[.", "].2 (once the first request is dispatched to either 1.1 or 1.2, later request should be sent to the same address) as shown in FIG. 2 , the HTTP request is automatically transmitted to the real application 31 by the browser 12 having received the redirect response, in accordance with the contents of the response.", "Owing to the offset by the redirect application A, the transmission destination (URL) of the request is 9.100.1[.", "].1/cluster1/ .", "or 9.100.1[.", "].1/cluster2/ .", "The destination address is converted into the cluster address 192.168.1[.", "].1 or 192.168.1[.", "].2 by the authentication server 21 , and then dispatched to the real address 192.168.0[.", "].1 or 192.168.0[.", "].2 by the load balancing server 22 .", "At the same time, in the browser 12 , the content (value or attribute) of the cookie transmitted in {circumflex over (2)} of FIG. 2 is saved in the memory or file on the client side.", "In {circumflex over (4)} Response with processed result as shown in FIG. 2 , it is unnecessary to change the real application 31 .", "The real application 31 processes the received HTTP request and returns a conventional response.", "The information inherited to the next HTTP request process is set by creating a session object, as needed.", "The session ID for identifying the session object is created by the Web application server 23 and set in the Set-Cookie header of the header in the response with processed result.", "The Path attribute (“/cluster1”", "or “/cluster2”", "depending on via which cluster address the real application 31 is initiated) is added to this cookie by the authentication server 21 .", "The cookie of the session ID is saved at the browser 12 having received the resultant response.", "Since then, this session ID is appended to the request transmitted to the same cluster address (address with the Path attribute of cookie matched), whereby the server program can gain access to the session information continually.", "FIG. 3 is a diagram showing an operation of the redirect application 32 (redirect application B) in response to a request in being restored from the other site 11 and the corresponding operation of the browser 12 .", "After the operation {circumflex over (4)} as shown in FIG. 2 , there are repetitive requests and responses between the self site 10 and the browser 12 .", "Thereafter, the HTTP request is transmitted to the other site 11 , followed by repetitive requests and responses to and from the other site 11 , in which the request transmitted to the self site 10 through the link in the HTML received from the other site 11 corresponds to {circumflex over (5)} as shown in FIG. 3 .", "In {circumflex over (5)} Request to the cluster address 192.168.1[.", "].0 the HTTP request transmitted to URL9.100.1[.", "].1/cluster0 designated from the other site 11 is converted into the cluster address 192.168.1[.", "].0 destination by the authentication server 21 , and further distributed to the real address 192.168.0[.", "].1 or 192.168.0[.", "].2 by the load balancing server 22 .", "The HTTP request initiates the redirect application B, but contains, as its arguments, the information specifying the real application 31 or the argument information required by the logic of the real application 31 .", "This request has a path part “/cluster0”, whereby the information of the session ID set in the cookie in {circumflex over (4)} of FIG. 2 is not transmitted from the browser 12 .", "Namely, the redirect application B can not gain access to the session information which is operative in the self site 10 previously.", "However, because the cookie of the cluster information transmitted in {circumflex over (2)} of FIG. 2 has the matched Path attribute, the cluster information is set in the request header and transmitted to the server side.", "The redirect application B can know via which cluster address the real application 31 should be initiated to gain access to the previous session information.", "The HTTP request of {circumflex over (5)} is processed by the redirect application B on the Web application server 23 to which the request is actually dispatched to create the {circumflex over (6)} redirect response.", "The redirect application B embeds the cluster address of the real application 31 in the redirect response, employing the cluster information read from the received request header.", "The arguments required for the logic of the real application 31 are also embedded directly into the redirect response.", "The browser 12 having received the redirect response transmits automatically the HTTP request to the real application 31 in accordance with the contents of the response.", "The transmission destination cluster address of the request is the same with the request in {circumflex over (7)} cluster address 192.168.1[.", "].1 or 192.168.1[.", "].2 as at the time of request in {circumflex over (3)}.", "Because the Path information is matched with the Path attribute of the cookie set in {circumflex over (4)} of FIG. 2 , the session ID is set in the request header and transmitted to the server side.", "In {circumflex over (8)} Reply with processed result in FIG. 3 , the real application 31 makes access to the session object with the received session ID as a key, and after execution of an affair logic, returns the result to the browser 12 .", "Then, the processing in the redirect application 32 will be described below.", "FIGS. 4A and 4B are flowcharts showing processes to be executed in the redirect application 32 .", "FIG. 4A shows a process for the redirect application A and FIG. 4B shows a process for the redirect application B. As shown in FIG. 4A , first of all, the redirect application A having received the HTTP request extracts and saves the associated parameters (step 101 ).", "Then, the information of the cluster address to be redirected is read from the configuration file of each Web application server 23 on which the redirect application 32 is operating (step 102 ).", "Then, the redirect application A creates a redirect response for initiating the real application 31 , employing the information of the parameters and the cluster address received upon the HTTP request (step 103 ).", "Thereafter, a Set-Cookie header is set in the header part of the HTTP response, and the cluster information is embedded into the cookie (step 104 ).", "And the redirect response that is prepared as the HTTP response is transmitted to the browser 12 (step 105 ), and the process of the redirect application A is ended.", "In the process of the redirect application B, first of all, the HTTP request is received, and the associated parameters are extracted and saved (step 111 ).", "Then, the information of the cluster address is acquired from the cookie set in the header part of the received HTTP request (step 112 ).", "Then, a redirect response for initiating the real application 31 is created, employing the information of the parameters and the cluster address received upon the HTTP request (step 113 ).", "And the redirect response that is prepared as the HTTP response is transmitted to the browser 12 (step 114 ), and the process of the redirect application B is ended.", "In this manner, in this embodiment, the cluster address of the real application 31 is embedded in the redirect response on the server side, whereby the browser 12 having received the response can make the redirect for automatically transmitting the request to this cluster address.", "More specifically, this “embedding”", "means that the cluster address is described in the HTTP header such as Java® Script or Location.", "Also, the cluster information as a cookie is set in the Set-Cookie header of the header for the redirect response on the server side, whereby the browser 12 having received the response stores this cluster information as a cookie in a memory or disk within the personal computer (PC).", "Since then, when the request is transmitted to the server, the browser 12 appends the stored cluster information as a part of the request data.", "FIG. 5 is a flowchart showing an automatic determination process for determining whether the redirect application A or the redirect application B is run in the redirect application 32 .", "First of all, an HTTP request is received, and the associated parameters are extracted and saved (step 151 ).", "Then, it is checked whether or not the cluster information as a cookie is embedded into the header part of the received HTTP request (step 152 ).", "If it is embedded, the cluster information from the header is acquired, and the information is employed as the cluster address (step 153 ).", "When it is not embedded as the cookie, the information of the cluster address is read from the configuration file of the server (step 154 ).", "Using the information of the cluster address obtained in this way, a redirect response for initiating the real application 31 is created (step 155 ).", "Herein, it is determined whether or not the cookie indicating the cluster information is set in the header part of the received HTTP request (step 156 ).", "When it is not set, the information is set as a cookie in the header part of the response (step 157 ), and the HTTP response is transmitted to the browser 12 (step 158 ).", "Thereby, the process is ended.", "With this embodiment, in a system configuration using a combination of the authentication server 21 and the load balancing server 22 on an IP layer basis, the session information can be inherited in a transition from the self site 10 to the other site 11 to the self site 10 .", "Also, in a system configuration using the authentication server 21 of the reverse proxy type, an application scenario in which the browser is moved from the self site 10 to the other site 11 , and moved back to the self site 10 again, is expected to increase in the future, along with the higher and more complex Web application.", "Also, in the Web site of the company, the use of the load balancing server 22 is indispensable from the viewpoint of reliability or scalability.", "Accordingly, it is considered that the problem of inheriting the session information will often arise in the future, and this embodiment to solve this problem is very valuable.", "As a cooperative scenario between the Web sites (self site 10 and other site 11 ) according to this embodiment, for example, it is conceived that the user moves from a Web site (self site 10 ) of an insurance company to a bank site (other site) where the user makes a loan on security of one's insurance to make a payment, and gets back to the Web site (self site 10 ) of the insurance company again to continue the operation.", "In such scenario, even if the user once moves to the bank site (other site 11 ), and then transfers to the Web site (self site 10 ) of the insurance company, the insurance contract operation can be continued.", "For example, there is a scenario where after a commodity is put in a shopping bag at a site (self site 10 ) in the shopping mall, the user transfers to another site (other site 11 ) of a credit company to confirm a schedule of withdrawal, and then is restored to the site (self site 10 ) in the shopping mall to carry out a purchase procedure.", "At this time, with this embodiment, in a system configuration in which the site (self site 10 ) of the shopping mall employs a combination of the authentication server 21 and the load balancing server 22 on an IP layer basis, the session information is enabled to be inherited when being restored from the other site 11 to the site (self site 10 ) in the shopping mall, whereby the operation can be smoothly continued even after transiting through a plurality of sites.", "Moreover, another scenario is applicable in which when making a reservation of the travel, the user moves to the site (other site 11 ) relevant with the hotels or inns halfway on the procedure of the site (self site 10 ) for making reservations of the transport facilities to make sure of the reservation, and then decides finally the reservation of the transport facilities at site (self site 10 ) for making reservations of the transport facilities.", "Then, with this embodiment, in a system configuration having a load balancing function at site (self site 10 ) for making reservations of the transport facilities, the session information is enabled to be inherited even in the case of transiting to the self site 10 after transferring to the other site 11 related with the reservation of the travel, whereby the reservation operation at site (self site 10 ) for making reservations of the transport facilities can be continued." ]
FIELD OF THE INVENTION [0001] The present invention relates generally to video games, and more specifically to special effects used in video games. BACKGROUND OF THE INVENTION [0002] The fun and excitement associated with many video games is increased when audio and visual effects are similar to real-life sounds and images. This is especially true with action combat games involving shooting and other weapons. Sounds may be related to an environmental activity or an impact activity. [0003] Environmental activity refers to activity surrounding the video game characters, such as flies buzzing, water running in a river, footsteps of a character running, a car engine running, etc. The sounds associated with environmental activities are typically not reactive, but rather are static in that they exist to enhance the presence of the object or person (“object” is used hereafter to refer to a physical object, person, or other living creature). Impact activity refers to “direct hits” on an object, such as a car blowing up from an explosive, a window shattering from a bullet, an alien or bad guy being shot, etc. The sounds associated with impact activities are typically due to the “direct hit.” [0004] In real life, objects may also react to secondary effects of an environmental or impact activity. For example, if a bomb explodes, a nearby fence may rattle in response to the resulting shockwave. Thus, the overall video game experience could be enhanced if the effect associated with an environmental and/or impact activity includes an output asset (e.g., audio, visual, audio-visual effect) triggered by a force other than a direct hit, to create a more real-life sensation during video game play. In other words, the asset is output in response to a secondary effect of the activity, such as the shockwave of an explosion. This adds to the player's envelopment in the virtual play space. SUMMARY OF THE INVENTION [0005] The output of an object in a video game includes an asset triggered by a secondary force, i.e., a force other than a direct hit on the object. Typically the force will be a secondary force from an environmental activity or an impact activity. The trigger is accomplished by a “reactive emitter,” which is a property associated with the object that is programmed into the video game to react to the secondary force. [0006] In preferred embodiments of the present invention, a method includes assigning a coverage zone to an activity in the video game, assigning a detection zone to an object in the video game, determining the coverage zone intersects with the detection zone, and causing the object to emit the asset based on the intersection of the coverage zone and the detection zone. The coverage zone is the area affected by a secondary effect of the activity. The detection zone is an area in the vicinity of the object. [0007] The asset may be an audio asset, a video asset, or an audio-video asset. The coverage zone and detection zone are typically substantially spherical, defined by a coverage radius and detection radius respectively. The activity is typically an explosion, and the secondary effect is a shockwave of the explosion. [0008] The output asset may vary in size/intensity based on the magnitude of intersection of the coverage zone and the detection zone. The output asset may also vary based on the type of object and/or the type of activity. If the output asset includes an audio component, the properties affected by these parameters may be pitch, volume, duration, and frequency. BRIEF DESCRIPTION OF THE DRAWINGS [0009] FIG. 1 is a flowchart of a method of the present invention. [0010] FIG. 2 is a geometric diagram showing intersections of various two-dimensional coverage zones and detection zones. [0011] FIG. 3 illustrates various 3 -dimensional coverage zones and detection zones. [0012] FIG. 4 shows a partial scene of a video game illustrating the coverage zone of an explosion intersecting with detection zones of various objects. DETAILED DESCRIPTION OF THE EMBODIMENTS [0013] Preferred embodiments of the present invention will now be described with reference to the above-described drawings. Beginning with FIG. 4 , a partial scene 400 from within a video game is shown, in which an explosion 430 is occurring. The scene 400 includes a building wall 410 , a car 415 , a barrel 420 , and a fence 425 . Also shown in FIG. 4 are dotted lines representing coverage zone 435 of the explosion 430 , and detection zones 440 , 445 , 450 , and 455 , of the wall 410 , car 415 , barrel 420 , and fence 425 respectively. The dotted lines are for illustration purposes only, and would not be visible during video game play as part of the scene 400 or otherwise. [0014] Coverage zone 435 is shown as substantially circular, as are detection zones 445 , 450 , and 455 . These zones could be any shape, including three-dimensional shapes such as substantially spherical. Detection zone 440 of wall 410 is shown as three-dimensional, specifically in the shape of a rectangular prism corresponding to the shape of the wall. Coverage zone 435 of explosion 430 represents the area affected by the shockwave of the explosion. In FIG. 4 , coverage zone 435 extends radially outward from the point of origin of explosion 430 , and intersects with each of detection zones 410 , 415 , 420 , and 425 . Thus, in accordance with preferred embodiments of the present invention, the shockwave of explosion 430 in scene 400 would cause each of objects 410 , 415 , 420 , and 425 to emit one or more assets. For example, as further described herein: wall 410 might shake, creak, and/or wobble etc.; car 415 might roll, tilt, spin, become airborne, have an airbag go off, have an alarm go off, and/or have the horn honk, etc.; barrel 420 might crack, split, roll, spin, become airborne, and/or discharge some or all of its contents, etc.; and fence 425 might rattle, buckle, and/or bend, etc. Various real-life sounds could be associated with the aforementioned. [0015] Turning now to FIG. 1 , a method to output an asset in a video game in accordance with the present invention is illustrated in a flowchart. The method begins at Step 100 . At Step 105 , a coverage zone is assigned to a secondary effect of an activity in the video game. The activity may be any activity generating a shockwave, pressure wave, or other secondary force. For example, the activity may be an explosion (as illustrated in FIG. 4 ) from a bomb, grenade, rocket, missile, or any other type of explosive. The activity may be a weather event or natural phenomenon such as an earthquake, lightning strike, hurricane, tornado, tsunami, volcanic eruption, etc. The activity may be a sonic boom from an aircraft, or a force wave from a supernatural power. The activity may be recoil or reverberation from firing a weapon, or a shockwave from a large building falling or an aircraft crashing. [0016] The coverage zone represents the area affected by the secondary effect of the activity. Typically the coverage zone is substantially spherical, and thus is defined by a coverage radius. When the activity is an explosion, the coverage radius is a blast radius. However, the coverage zone may be any geometric shape or irregular area, and may even be three-dimensional. Various three-dimensional coverage zones are shown, e.g., in FIG. 3 . Specifically: a cylindrical zone 305 is shown for an activity centered at 320 ; a conical zone 310 is shown for an activity centered at 325 ; and a spherical zone 315 is shown for an activity centered at 330 . [0017] The coverage zone is programmed into the video game by associating the zone with the activity. The coverage zone may be constant for the activity, or may vary depending on other parameters. For example, a certain type of explosion may always have a blast radius of 15 feet, or that type of explosion may have a blast radius varying from 5 feet to 25 feet, depending on parameters such as which character triggered the explosion, the weather conditions, whether the weapon causing the explosion has been enhanced, etc. Or the range may be randomly generated. Multiple activities may have corresponding coverage zones assigned to their corresponding secondary effects at Step 105 . The coverage zones may be assigned as part of the video game development, or dynamically during video game play. [0018] At Step 110 , a detection zone is assigned to an object in the video game. Objects may be fences, barrels, walls, windows, cars or other vehicles, boxes, poles, trees, bushes, dirt, leaves, rocks, water, structures, or anything else. Multiple objects may be assigned corresponding detection zones at Step 110 . Assignment of detection zones to objects may occur before, after, or simultaneously with assigning coverage zones to the secondary effects of activities at Step 105 . The detection zones may be assigned as part of the video game development, or dynamically during video game play. Various detection zones 440 , 445 , 450 , and 455 are shown in FIG. 4 . Typically detection zones are substantially spherical, and thus are defined by a detection radius. [0019] During video game play, when an activity occurs having a coverage zone, if the coverage zone intersects with the detection zone of an object, the object will emit an asset based on the intersection. Determination of the intersection occurs at Step 115 , and is discussed in more detail herein with reference to FIGS. 2 and 3 . The object emits the asset at Step 120 . The asset may be audio, visual, audio-visual, or even another sensory asset such as a smell, flavor, or tactile output. The asset may have properties associated therewith, and the values of those properties are referred to herein as the asset's payload. For example, a sound asset may have properties of pitch, volume, duration, frequency, etc., each assigned a value. A video asset may have properties of direction, speed, condition, color, axis of rotation, discharge, deformation, etc., each assigned a value. [0020] As an example, if an explosion occurs generating a shockwave with a coverage zone intersecting the detection zone of a barrel, the barrel may shake, roll, break, and discharge its contents, all with accompanying lifelike sounds. Similarly, if the coverage zone intersects the detection zone of a car, the car may spin, become airborne, and have its hood pop off when it lands, all with accompanying lifelike sounds. If the coverage zone intersects the detection zone of a fence, the fence may rattle, buckle, or dislodge, all with accompanying lifelike sounds. If the coverage zone intersects the detection zone of a wall or building, the wall or building may shake, crumble, crack, or have portions dislodged, all with accompanying lifelike sounds. [0021] The scope and extent of the asset or assets emitted may be determined by various factors. For example, an object may have fixed assets associated therewith. In such a case, the object would emit the same asset(s) whenever its detection zone intersected a coverage zone. Or an object may have various fixed assets associated therewith corresponding to various known activities. In such a case, the asset(s) emitted would depend on the activity associated with the coverage zone intersecting the object's detection zone. Various objects may have various assets assigned thereto depending on the type of the object. Objects may be classified into different types such as human, inanimate, extraterrestrial, etc., and may be further classified into sub-types such as by size, stability, foundation, material composition, etc. Such classifications may be determined at the programming level (as may classifications of activities). [0022] Further, the payload of an asset may depend on various factors. For example, the payload may vary as the magnitude of the intersection between the coverage zone and the detection zone varies. In other words, if an object's detection zone barely intersects an activity's coverage zone, the payload may be minimal, whereas if the object's detection zone significantly intersects an activity's coverage zone, the payload may be more significant. The payload may also vary depending on the type of object (as previously described) and/or the type of activity. Activities may be classified into different types such as weather, explosion, structural, supernatural, etc. Or each activity may have its own unique payload associated therewith. An activity with a short duration and high frequency may cause the object to emit a short more “pingy” payload as compared to a longer low-frequency activity. [0023] Turning now to FIG. 2 , intersections of various two-dimensional coverage zones ( 205 , 210 , 220 , and 225 ) and detection zones ( 215 and 230 ) are shown in a geometric diagram. The coverage zones 205 , 210 , 220 , and 225 represent areas affected by secondary effects of various activities centered at 235 , 240 , 250 , and 255 respectively. The zones are all circular, and thus have coverage radii 265 , 270 , 280 , and 285 respectively. The activities may occur substantially simultaneously or at different times during the video game. The detection zones 215 and 230 represent areas in the vicinities of objects centered at 245 and 260 respectively, and are also circular and thus have detection radii 275 and 290 respectively. [0024] As can be seen, not all of the coverage zones 205 , 210 , 220 , and 225 intersect both of the detection zones 215 (for object centered at 245 ) and 225 (for object centered at 260 ). Starting with coverage zone 205 of activity centered at 235 , this zone does not intersect with either of detection zones 215 or 230 . Thus, occurrence of this activity would not cause either of those objects to emit an asset. Coverage zones 210 and 220 intersect detection zone 215 , but does not intersect detection zone 230 . Thus, occurrence of the activities centered at 240 and 250 would cause the object centered at 245 to emit an asset, but would not cause the object centered at 260 to emit an asset. And coverage zone 225 intersects detection zone 230 , but does not intersect detection zone 215 . Thus, occurrence of the activity centered at 255 would cause the object centered at 260 to emit an asset, but would not cause the object centered at 245 to emit an asset. [0025] As already mentioned, the output asset may vary in intensity based on a determination of the magnitude of intersection of the coverage zone and the detection zone. For example, the asset's payload may increase as the magnitude of the intersection between the coverage zone and the detection zone increases. Determination of the size/intensity of the payload may be based on a percent of intersection of the coverage zone and detection zone, and/or some other linear or exponential function dependent on proximity of the activity to the object, intervening obstacles, etc. In FIG. 2 , for example, coverage zones 210 and 220 intersect with detection zone 215 at 295 and 297 respectively. Those intersections are small compared to intersection 299 of coverage zone 225 and detection zone 230 . Thus, if a payload is directly proportional to the magnitude of intersection, the payload of the object centered at 260 based on the activity centered at 255 would be greater than the payload of the object centered at 245 based on either of the activities centered at 240 or 250 . [0026] As an example of modifying assets based on the magnitude of intersection of the applicable coverage zone and detection zone, a barrel at 245 might react to activity at 240 or 250 by slightly wobbling or tilting over, with a low volume corresponding sound. On the other hand, a barrel at 260 might react to activity at 255 by being ejected into the air and breaking apart, with loud thuds as the pieces land. Any or all of audio properties of pitch, volume, duration, and frequency, may be adjusted accordingly based on the magnitude of intersection. [0027] Also as already mentioned, the output asset may vary based on the type of object and/or the type of activity. For example, all metal objects may have specific sounds associated with them, whereas all liquid objects may have other specific sounds associated with them. Objects may be classified as broadly or narrowly as is desired. Likewise, activities may be classified as broadly or narrowly as desired. An object's output asset(s) may depend on the type of activity associated with the coverage zone. Such assets for any object or type/class of objects may be mapped to any activity or class/type of activity as desired. [0028] Additionally, detection areas may vary for an object, depending on the type of activity. For example, a barrel might have one detection zone for weather-related activities, and a different detection zone for explosions. Or the barrel might have one detection zone for earthquakes, and a different detection zone for lightning strikes. Detection zones may also be randomly generated. [0029] Although particular embodiments have been shown and described, the above description is not intended to limit the scope of these embodiments. While embodiments and variations of the many aspects of the invention have been disclosed and described herein, such disclosure is provided for purposes of explanation and illustration only. Thus, various changes and modifications may be made without departing from the scope of the claims. Accordingly, embodiments are intended to exemplify alternatives, modifications, and equivalents that may fall within the scope of the claims. The invention, therefore, should not be limited, except to the following claims, and their equivalents.
A reactive emitter associated with an object in a video game emits an asset in response to a secondary effect of an activity that occurs in the video game within a vicinity of the object.
Briefly summarize the invention's components and working principles as described in the document.
[ "FIELD OF THE INVENTION [0001] The present invention relates generally to video games, and more specifically to special effects used in video games.", "BACKGROUND OF THE INVENTION [0002] The fun and excitement associated with many video games is increased when audio and visual effects are similar to real-life sounds and images.", "This is especially true with action combat games involving shooting and other weapons.", "Sounds may be related to an environmental activity or an impact activity.", "[0003] Environmental activity refers to activity surrounding the video game characters, such as flies buzzing, water running in a river, footsteps of a character running, a car engine running, etc.", "The sounds associated with environmental activities are typically not reactive, but rather are static in that they exist to enhance the presence of the object or person (“object”", "is used hereafter to refer to a physical object, person, or other living creature).", "Impact activity refers to “direct hits”", "on an object, such as a car blowing up from an explosive, a window shattering from a bullet, an alien or bad guy being shot, etc.", "The sounds associated with impact activities are typically due to the “direct hit.”", "[0004] In real life, objects may also react to secondary effects of an environmental or impact activity.", "For example, if a bomb explodes, a nearby fence may rattle in response to the resulting shockwave.", "Thus, the overall video game experience could be enhanced if the effect associated with an environmental and/or impact activity includes an output asset (e.g., audio, visual, audio-visual effect) triggered by a force other than a direct hit, to create a more real-life sensation during video game play.", "In other words, the asset is output in response to a secondary effect of the activity, such as the shockwave of an explosion.", "This adds to the player's envelopment in the virtual play space.", "SUMMARY OF THE INVENTION [0005] The output of an object in a video game includes an asset triggered by a secondary force, i.e., a force other than a direct hit on the object.", "Typically the force will be a secondary force from an environmental activity or an impact activity.", "The trigger is accomplished by a “reactive emitter,” which is a property associated with the object that is programmed into the video game to react to the secondary force.", "[0006] In preferred embodiments of the present invention, a method includes assigning a coverage zone to an activity in the video game, assigning a detection zone to an object in the video game, determining the coverage zone intersects with the detection zone, and causing the object to emit the asset based on the intersection of the coverage zone and the detection zone.", "The coverage zone is the area affected by a secondary effect of the activity.", "The detection zone is an area in the vicinity of the object.", "[0007] The asset may be an audio asset, a video asset, or an audio-video asset.", "The coverage zone and detection zone are typically substantially spherical, defined by a coverage radius and detection radius respectively.", "The activity is typically an explosion, and the secondary effect is a shockwave of the explosion.", "[0008] The output asset may vary in size/intensity based on the magnitude of intersection of the coverage zone and the detection zone.", "The output asset may also vary based on the type of object and/or the type of activity.", "If the output asset includes an audio component, the properties affected by these parameters may be pitch, volume, duration, and frequency.", "BRIEF DESCRIPTION OF THE DRAWINGS [0009] FIG. 1 is a flowchart of a method of the present invention.", "[0010] FIG. 2 is a geometric diagram showing intersections of various two-dimensional coverage zones and detection zones.", "[0011] FIG. 3 illustrates various 3 -dimensional coverage zones and detection zones.", "[0012] FIG. 4 shows a partial scene of a video game illustrating the coverage zone of an explosion intersecting with detection zones of various objects.", "DETAILED DESCRIPTION OF THE EMBODIMENTS [0013] Preferred embodiments of the present invention will now be described with reference to the above-described drawings.", "Beginning with FIG. 4 , a partial scene 400 from within a video game is shown, in which an explosion 430 is occurring.", "The scene 400 includes a building wall 410 , a car 415 , a barrel 420 , and a fence 425 .", "Also shown in FIG. 4 are dotted lines representing coverage zone 435 of the explosion 430 , and detection zones 440 , 445 , 450 , and 455 , of the wall 410 , car 415 , barrel 420 , and fence 425 respectively.", "The dotted lines are for illustration purposes only, and would not be visible during video game play as part of the scene 400 or otherwise.", "[0014] Coverage zone 435 is shown as substantially circular, as are detection zones 445 , 450 , and 455 .", "These zones could be any shape, including three-dimensional shapes such as substantially spherical.", "Detection zone 440 of wall 410 is shown as three-dimensional, specifically in the shape of a rectangular prism corresponding to the shape of the wall.", "Coverage zone 435 of explosion 430 represents the area affected by the shockwave of the explosion.", "In FIG. 4 , coverage zone 435 extends radially outward from the point of origin of explosion 430 , and intersects with each of detection zones 410 , 415 , 420 , and 425 .", "Thus, in accordance with preferred embodiments of the present invention, the shockwave of explosion 430 in scene 400 would cause each of objects 410 , 415 , 420 , and 425 to emit one or more assets.", "For example, as further described herein: wall 410 might shake, creak, and/or wobble etc.", "car 415 might roll, tilt, spin, become airborne, have an airbag go off, have an alarm go off, and/or have the horn honk, etc.", "barrel 420 might crack, split, roll, spin, become airborne, and/or discharge some or all of its contents, etc.", "and fence 425 might rattle, buckle, and/or bend, etc.", "Various real-life sounds could be associated with the aforementioned.", "[0015] Turning now to FIG. 1 , a method to output an asset in a video game in accordance with the present invention is illustrated in a flowchart.", "The method begins at Step 100 .", "At Step 105 , a coverage zone is assigned to a secondary effect of an activity in the video game.", "The activity may be any activity generating a shockwave, pressure wave, or other secondary force.", "For example, the activity may be an explosion (as illustrated in FIG. 4 ) from a bomb, grenade, rocket, missile, or any other type of explosive.", "The activity may be a weather event or natural phenomenon such as an earthquake, lightning strike, hurricane, tornado, tsunami, volcanic eruption, etc.", "The activity may be a sonic boom from an aircraft, or a force wave from a supernatural power.", "The activity may be recoil or reverberation from firing a weapon, or a shockwave from a large building falling or an aircraft crashing.", "[0016] The coverage zone represents the area affected by the secondary effect of the activity.", "Typically the coverage zone is substantially spherical, and thus is defined by a coverage radius.", "When the activity is an explosion, the coverage radius is a blast radius.", "However, the coverage zone may be any geometric shape or irregular area, and may even be three-dimensional.", "Various three-dimensional coverage zones are shown, e.g., in FIG. 3 .", "Specifically: a cylindrical zone 305 is shown for an activity centered at 320 ;", "a conical zone 310 is shown for an activity centered at 325 ;", "and a spherical zone 315 is shown for an activity centered at 330 .", "[0017] The coverage zone is programmed into the video game by associating the zone with the activity.", "The coverage zone may be constant for the activity, or may vary depending on other parameters.", "For example, a certain type of explosion may always have a blast radius of 15 feet, or that type of explosion may have a blast radius varying from 5 feet to 25 feet, depending on parameters such as which character triggered the explosion, the weather conditions, whether the weapon causing the explosion has been enhanced, etc.", "Or the range may be randomly generated.", "Multiple activities may have corresponding coverage zones assigned to their corresponding secondary effects at Step 105 .", "The coverage zones may be assigned as part of the video game development, or dynamically during video game play.", "[0018] At Step 110 , a detection zone is assigned to an object in the video game.", "Objects may be fences, barrels, walls, windows, cars or other vehicles, boxes, poles, trees, bushes, dirt, leaves, rocks, water, structures, or anything else.", "Multiple objects may be assigned corresponding detection zones at Step 110 .", "Assignment of detection zones to objects may occur before, after, or simultaneously with assigning coverage zones to the secondary effects of activities at Step 105 .", "The detection zones may be assigned as part of the video game development, or dynamically during video game play.", "Various detection zones 440 , 445 , 450 , and 455 are shown in FIG. 4 .", "Typically detection zones are substantially spherical, and thus are defined by a detection radius.", "[0019] During video game play, when an activity occurs having a coverage zone, if the coverage zone intersects with the detection zone of an object, the object will emit an asset based on the intersection.", "Determination of the intersection occurs at Step 115 , and is discussed in more detail herein with reference to FIGS. 2 and 3 .", "The object emits the asset at Step 120 .", "The asset may be audio, visual, audio-visual, or even another sensory asset such as a smell, flavor, or tactile output.", "The asset may have properties associated therewith, and the values of those properties are referred to herein as the asset's payload.", "For example, a sound asset may have properties of pitch, volume, duration, frequency, etc.", ", each assigned a value.", "A video asset may have properties of direction, speed, condition, color, axis of rotation, discharge, deformation, etc.", ", each assigned a value.", "[0020] As an example, if an explosion occurs generating a shockwave with a coverage zone intersecting the detection zone of a barrel, the barrel may shake, roll, break, and discharge its contents, all with accompanying lifelike sounds.", "Similarly, if the coverage zone intersects the detection zone of a car, the car may spin, become airborne, and have its hood pop off when it lands, all with accompanying lifelike sounds.", "If the coverage zone intersects the detection zone of a fence, the fence may rattle, buckle, or dislodge, all with accompanying lifelike sounds.", "If the coverage zone intersects the detection zone of a wall or building, the wall or building may shake, crumble, crack, or have portions dislodged, all with accompanying lifelike sounds.", "[0021] The scope and extent of the asset or assets emitted may be determined by various factors.", "For example, an object may have fixed assets associated therewith.", "In such a case, the object would emit the same asset(s) whenever its detection zone intersected a coverage zone.", "Or an object may have various fixed assets associated therewith corresponding to various known activities.", "In such a case, the asset(s) emitted would depend on the activity associated with the coverage zone intersecting the object's detection zone.", "Various objects may have various assets assigned thereto depending on the type of the object.", "Objects may be classified into different types such as human, inanimate, extraterrestrial, etc.", ", and may be further classified into sub-types such as by size, stability, foundation, material composition, etc.", "Such classifications may be determined at the programming level (as may classifications of activities).", "[0022] Further, the payload of an asset may depend on various factors.", "For example, the payload may vary as the magnitude of the intersection between the coverage zone and the detection zone varies.", "In other words, if an object's detection zone barely intersects an activity's coverage zone, the payload may be minimal, whereas if the object's detection zone significantly intersects an activity's coverage zone, the payload may be more significant.", "The payload may also vary depending on the type of object (as previously described) and/or the type of activity.", "Activities may be classified into different types such as weather, explosion, structural, supernatural, etc.", "Or each activity may have its own unique payload associated therewith.", "An activity with a short duration and high frequency may cause the object to emit a short more “pingy”", "payload as compared to a longer low-frequency activity.", "[0023] Turning now to FIG. 2 , intersections of various two-dimensional coverage zones ( 205 , 210 , 220 , and 225 ) and detection zones ( 215 and 230 ) are shown in a geometric diagram.", "The coverage zones 205 , 210 , 220 , and 225 represent areas affected by secondary effects of various activities centered at 235 , 240 , 250 , and 255 respectively.", "The zones are all circular, and thus have coverage radii 265 , 270 , 280 , and 285 respectively.", "The activities may occur substantially simultaneously or at different times during the video game.", "The detection zones 215 and 230 represent areas in the vicinities of objects centered at 245 and 260 respectively, and are also circular and thus have detection radii 275 and 290 respectively.", "[0024] As can be seen, not all of the coverage zones 205 , 210 , 220 , and 225 intersect both of the detection zones 215 (for object centered at 245 ) and 225 (for object centered at 260 ).", "Starting with coverage zone 205 of activity centered at 235 , this zone does not intersect with either of detection zones 215 or 230 .", "Thus, occurrence of this activity would not cause either of those objects to emit an asset.", "Coverage zones 210 and 220 intersect detection zone 215 , but does not intersect detection zone 230 .", "Thus, occurrence of the activities centered at 240 and 250 would cause the object centered at 245 to emit an asset, but would not cause the object centered at 260 to emit an asset.", "And coverage zone 225 intersects detection zone 230 , but does not intersect detection zone 215 .", "Thus, occurrence of the activity centered at 255 would cause the object centered at 260 to emit an asset, but would not cause the object centered at 245 to emit an asset.", "[0025] As already mentioned, the output asset may vary in intensity based on a determination of the magnitude of intersection of the coverage zone and the detection zone.", "For example, the asset's payload may increase as the magnitude of the intersection between the coverage zone and the detection zone increases.", "Determination of the size/intensity of the payload may be based on a percent of intersection of the coverage zone and detection zone, and/or some other linear or exponential function dependent on proximity of the activity to the object, intervening obstacles, etc.", "In FIG. 2 , for example, coverage zones 210 and 220 intersect with detection zone 215 at 295 and 297 respectively.", "Those intersections are small compared to intersection 299 of coverage zone 225 and detection zone 230 .", "Thus, if a payload is directly proportional to the magnitude of intersection, the payload of the object centered at 260 based on the activity centered at 255 would be greater than the payload of the object centered at 245 based on either of the activities centered at 240 or 250 .", "[0026] As an example of modifying assets based on the magnitude of intersection of the applicable coverage zone and detection zone, a barrel at 245 might react to activity at 240 or 250 by slightly wobbling or tilting over, with a low volume corresponding sound.", "On the other hand, a barrel at 260 might react to activity at 255 by being ejected into the air and breaking apart, with loud thuds as the pieces land.", "Any or all of audio properties of pitch, volume, duration, and frequency, may be adjusted accordingly based on the magnitude of intersection.", "[0027] Also as already mentioned, the output asset may vary based on the type of object and/or the type of activity.", "For example, all metal objects may have specific sounds associated with them, whereas all liquid objects may have other specific sounds associated with them.", "Objects may be classified as broadly or narrowly as is desired.", "Likewise, activities may be classified as broadly or narrowly as desired.", "An object's output asset(s) may depend on the type of activity associated with the coverage zone.", "Such assets for any object or type/class of objects may be mapped to any activity or class/type of activity as desired.", "[0028] Additionally, detection areas may vary for an object, depending on the type of activity.", "For example, a barrel might have one detection zone for weather-related activities, and a different detection zone for explosions.", "Or the barrel might have one detection zone for earthquakes, and a different detection zone for lightning strikes.", "Detection zones may also be randomly generated.", "[0029] Although particular embodiments have been shown and described, the above description is not intended to limit the scope of these embodiments.", "While embodiments and variations of the many aspects of the invention have been disclosed and described herein, such disclosure is provided for purposes of explanation and illustration only.", "Thus, various changes and modifications may be made without departing from the scope of the claims.", "Accordingly, embodiments are intended to exemplify alternatives, modifications, and equivalents that may fall within the scope of the claims.", "The invention, therefore, should not be limited, except to the following claims, and their equivalents." ]
TECHNICAL FIELD [0001] The present invention relates to mobile telephones an in particular to a method and an apparatus for preventing use of mobile telephones in situations where it is undesirable. DESCRIPTION OF RELATED ART [0002] Mobile telephones and other terminals utilizing wireless communication, such as personal computers, are being used to an increasing extent. In some cases this is very annoying to other people, for example, telephones ringing during concerts or at cinemas. Some times the owner of the phone even answers and engages in a conversation without leaving the room. [0003] In hospitals, for example, radio signals transmitted by mobile telephones sometimes interfere with technical equipment. In airplanes all use of equipment containing radio transmitters is prohibited because they may interfere with the control electronics. Even in these situations, people sometimes ignore the ban on this type of equipment, or just forget to turn their mobile telephones off when entering an air plane or hospital area, or a concert hall or the like. [0004] Patent specifications WO 96/29687 and U.S. Pat. No. 5,543,779 both describe methods for detecting any mobile telephones nearby that are engaged in communication with a base station. With this method, only a few of the mobile telephones present will be detected, and they will be so at a stage when the mobile telephone is already transmitting signals to the base station. This means that sensitive equipment may already be disturbed and it is probably too late to stop the telephone from ringing. OBJECT OF THE INVENTION [0005] It is an object of the invention to enable the detection and/or prevention of the use of radio communication equipment in situations or places in which such use is undesirable. SUMMARY OF THE INVENTION [0006] This object is achieved according to the invention by a first radio communication device adapted to [0007] transmit a radio signal instructing other radio communication devices within a certain range from the unit to identify themselves; [0008] receive and interpret the response signals; and, [0009] in dependence of the response signal received from each radio communication device: [0010] transmit a message to the radio communication device [0011] transmit a message to the user of the radio communication device, or [0012] order the radio communication device to turn itself off. [0013] The object is also achieved by a portable radio communication device comprising means for communicating in a cellular telephone network and low power radio communication means [0014] characterized in that it comprises means for [0015] in response to a low power radio message instructing it to identify itself, transmitting a response signal; [0016] receiving a message and/or instructions and act upon them. [0017] The object is also achieved according to the invention by a method of controlling the use of mobile terminals, comprising the following steps: [0018] transmitting a radio signal from a central unit instructing all radio communication units within a certain range to identify themselves [0019] transmitting response signals from each portable radio communication unit within the range; [0020] transmitting instructions from the central unit to each portable radio communication units in dependence of the content of the response signal; [0021] the portable radio communication unit responding to the instructions. [0022] In this way, portable radio communications device may be switched off automatically by the first radio communication device, or the user of the mobile phone can be reminded that the phone should be turned off. [0023] According to a preferred embodiment the first radio communication device is adapted to transmit an alarm if all mobile terminals do not respond to said message or order within a certain time period. [0024] According to another embodiment the portable radio communication device is adapted to shut itself down when instructions to do so are received. [0025] Instructions may also, instead of a shutdown command, comprise the order to notify the person carrying the portable radio. [0026] It is foreseen that in a few years' time, most mobile telephones will include low power radio transmitters having a range of, typically, 10 m or 100 m, for example according to the Bluetooth standard. These radio transmitters will be used for a number of purposes: [0027] For signalling to and from a telephone in the PSTN network so that the mobile telephone can be used as a cordless phone in the PSTN network when the user is close enough to his/her home telephone, or to connect a wireless headset to either the mobile phone or to the PSTN network using Bluetooth. [0028] To transmit data between the mobile telephone and other units, for example personal computer, for example, if the user keeps a diary and/or a phone book in the mobile phone and wants the diary and/or phone book in his/her PC to be updated with information from the mobile telephone. [0029] These functions are described, for example, in WO97/34403 and WO 98/11707. BRIEF DESCRIPTION OF THE DRAWINGS [0030] In the following, the invention will be described in more detail, by way of preferred embodiments and with reference to the drawings, in which: [0031] [0031]FIG. 1 is an overall schematic representation of the units according to the invention and how they interact; [0032] [0032]FIG. 2 is a schematic representation of a mobile telephone according to one embodiment of the invention; [0033] [0033]FIGS. 3A and 3B are flow charts of a first and a second embodiment of the method according to the invention. DETAILED DESCRIPTION OF EMBODIMENTS [0034] [0034]FIG. 1 is a schematic representation of the units according to the invention. In this example the method according to the invention is implemented for a building 1 , but it may just as well be an airplane, or the gate area at an airport, or any other area. [0035] In the building 1 , there are a number of mobile telephones 3 , 5 that may be used for mobile communication in mobile telephone networks, represented in the Figure by a base station 7 . This type of communication is well known in the art. The mobile telephones 3 may operate according to any standard known in the art, including Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), and Wideband CDMA. Accordingly the mobile terminals will not all connect to the same base station. Each mobile terminal will connect to a base station 7 in a network providing the appropriate standard. However, for simplicity, only one base station is shown in this figure, since the communication between the mobile telephones and the telephone networks is not essential to the invention. [0036] In the example, one mobile telephone 3 in the building 1 is currently involved in a connection to the base station 7 . Another mobile phone 5 is not involved in a connection, but is turned on. There may be other telephones in the building that are not turned on. These phones will not be affected by the invention, and are not shown. There are, of course, also a number of mobile telephones 9 outside the building. [0037] In the building 1 there is also a central radio unit 11 comprising a transmitter 13 transmitting low power radio signals. The power of the radio signals is adjusted so that the signal will be received by mobile telephones 3 , 5 inside the building, but not the mobile telephones 9 outside the building. [0038] The low power radio signal tells the mobile telephones 3 , 5 to respond by transmitting a similar signal to identify themselves to the central unit 11 , for example, by the type of equipment they are. This signal is received by a receiving part 15 and processed in a processor 17 in the central unit 11 . This identification is necessary, or at least desirable, to make sure that only equipment that really has to be turned off is, especially in the cases when an alert is sent out if all radio transmitting equipment is not turned off. For example, there is no need to turn off television sets or radios. The processor 17 also controls the transmitting and receiving parts 13 , 15 . [0039] In order for the method according to the invention to work, the mobile telephone must include a low power radio transmitter of the specified kind, and software for handling the functions, as will be described in connection with FIGS. 2 and 3. For mobile phones not including such units, a piece of additional equipment may be used to enable the mobile phone to communicate with the central radio unit. [0040] [0040]FIG. 2 shows a general mobile telephone 21 according to the invention. As an example, a GSM telephone is shown. [0041] The telephone shown in FIG. 2 comprises an antenna 27 used to receive and transmit signals through the air interface. The signals received by the antenna are processed in a radio unit 29 and a processing unit 31 before they are played to the subscriber through a loudspeaker 33 . The actual processing steps performed, such as demodulation, D/A conversion equalization and decoding, depend on the signalling system and are well known to the person skilled in the art. Speech is registered by a microphone 35 and processed by the processing unit 31 and the radio unit 29 before it is transmitted from the antenna 27 . As common in the art, the processor may also control a keyset and display (not shown). [0042] According to the invention, the telephone also comprises a short-range radio transmitter unit 37 , for example, a Bluetooth transmitter, controlled by the processing unit 31 . [0043] As discussed above, the short-range radio transmitter included in the mobile terminal according to the invention may, and probably will, be used for other purposes than that according to the invention. [0044] If the hardware and/or software needed for the method according to the invention is not included in the mobile terminal, a plug-in unit comprising the necessary hardware and software can instead be connected to the mobile telephone. [0045] [0045]FIG. 3A is a flow chart of the method according to a first embodiment of the invention: [0046] Step 101 : The central unit sends out a request signal requesting all mobile telephones and other units transmitting radio signals to identify themselves. [0047] Step 102 : Each radio transmitting unit, when receiving the signal from the central unit, identifies itself to the central unit by a response signal. This signal preferably includes the type of unit and the type or types of communication it may engage in. [0048] Step 103 : The central unit interprets each of the response signals received, and determines for each communication device that has responded, if this device has to be turned off or not, or to be partially turned off. [0049] Step 104 : If the device should be turned off, go to step 105 ; if an instruction or another message should be sent to the device , go to step 107 ; if nothing should happen, end of procedure. [0050] Step 105 : The central unit orders the device to turn itself off. [0051] Step 106 : The device turns itself off. The next time a request signal is sent out from the central unit, this device will not be registered. End of procedure. [0052] Step 107 : The central unit sends a message to the communication device. Any type of message that the device can handle may be sent, for example “turn of mobile phones”, or “switch to short distance radio for communication”. End of procedure. [0053] [0053]FIG. 3B is a flow chart of the method according to a second embodiment of the invention: [0054] Step 201 : The central unit sends out a request signal requesting all mobile telephones or other units transmitting radio signals to identify themselves. [0055] Step 202 : Each unit transmitting radio signals, when receiving the signal from the central unit, identifies itself to the central unit by a response signal. [0056] Step 203 : The central unit interprets each of the response signals received, and determines for each communication device that has responded, if this device has to be turned off or not. [0057] Step 204 : If the device should be turned off, go to step 205 ; if nothing should happen, end of procedure. [0058] Step 205 : The central unit orders the device to turn itself off. If the device offers several communication functions, for example, communication in a cellular network, which may be dangerous, and low power radio communication, only the undesired functions will have to be turned off, for example, the long-distance radio transmitting parts. [0059] Step 206 : The device transmits a confirmation signal to the central unit, then turns itself off. [0060] Step 207 : If confirmation signals are not received from all devices that should be turned off, within a certain amount of time, a message may be transmitted. This may be a private alert to the owner of the device that was not turned off, or a public alert or alarm. For example, in airplanes or in hospitals, a public alert may be appropriate to draw attention to the fact that electronic equipment may be disturbed. End of procedure.
To detect and/or prevent the use of radio communication equipment in situations or places in which such use is undesirable, according to the invention a short-range radio communication unit may be used to detect portable radio communications unit in the vicinity and transmit to any such units that are turned on, either a command to turn them off or a message to the bearer of the phone. The telephone also comprises a short-range radio communications unit for this purpose.
Summarize the patent document, focusing on the invention's functionality and advantages.
[ "TECHNICAL FIELD [0001] The present invention relates to mobile telephones an in particular to a method and an apparatus for preventing use of mobile telephones in situations where it is undesirable.", "DESCRIPTION OF RELATED ART [0002] Mobile telephones and other terminals utilizing wireless communication, such as personal computers, are being used to an increasing extent.", "In some cases this is very annoying to other people, for example, telephones ringing during concerts or at cinemas.", "Some times the owner of the phone even answers and engages in a conversation without leaving the room.", "[0003] In hospitals, for example, radio signals transmitted by mobile telephones sometimes interfere with technical equipment.", "In airplanes all use of equipment containing radio transmitters is prohibited because they may interfere with the control electronics.", "Even in these situations, people sometimes ignore the ban on this type of equipment, or just forget to turn their mobile telephones off when entering an air plane or hospital area, or a concert hall or the like.", "[0004] Patent specifications WO 96/29687 and U.S. Pat. No. 5,543,779 both describe methods for detecting any mobile telephones nearby that are engaged in communication with a base station.", "With this method, only a few of the mobile telephones present will be detected, and they will be so at a stage when the mobile telephone is already transmitting signals to the base station.", "This means that sensitive equipment may already be disturbed and it is probably too late to stop the telephone from ringing.", "OBJECT OF THE INVENTION [0005] It is an object of the invention to enable the detection and/or prevention of the use of radio communication equipment in situations or places in which such use is undesirable.", "SUMMARY OF THE INVENTION [0006] This object is achieved according to the invention by a first radio communication device adapted to [0007] transmit a radio signal instructing other radio communication devices within a certain range from the unit to identify themselves;", "[0008] receive and interpret the response signals;", "and, [0009] in dependence of the response signal received from each radio communication device: [0010] transmit a message to the radio communication device [0011] transmit a message to the user of the radio communication device, or [0012] order the radio communication device to turn itself off.", "[0013] The object is also achieved by a portable radio communication device comprising means for communicating in a cellular telephone network and low power radio communication means [0014] characterized in that it comprises means for [0015] in response to a low power radio message instructing it to identify itself, transmitting a response signal;", "[0016] receiving a message and/or instructions and act upon them.", "[0017] The object is also achieved according to the invention by a method of controlling the use of mobile terminals, comprising the following steps: [0018] transmitting a radio signal from a central unit instructing all radio communication units within a certain range to identify themselves [0019] transmitting response signals from each portable radio communication unit within the range;", "[0020] transmitting instructions from the central unit to each portable radio communication units in dependence of the content of the response signal;", "[0021] the portable radio communication unit responding to the instructions.", "[0022] In this way, portable radio communications device may be switched off automatically by the first radio communication device, or the user of the mobile phone can be reminded that the phone should be turned off.", "[0023] According to a preferred embodiment the first radio communication device is adapted to transmit an alarm if all mobile terminals do not respond to said message or order within a certain time period.", "[0024] According to another embodiment the portable radio communication device is adapted to shut itself down when instructions to do so are received.", "[0025] Instructions may also, instead of a shutdown command, comprise the order to notify the person carrying the portable radio.", "[0026] It is foreseen that in a few years'", "time, most mobile telephones will include low power radio transmitters having a range of, typically, 10 m or 100 m, for example according to the Bluetooth standard.", "These radio transmitters will be used for a number of purposes: [0027] For signalling to and from a telephone in the PSTN network so that the mobile telephone can be used as a cordless phone in the PSTN network when the user is close enough to his/her home telephone, or to connect a wireless headset to either the mobile phone or to the PSTN network using Bluetooth.", "[0028] To transmit data between the mobile telephone and other units, for example personal computer, for example, if the user keeps a diary and/or a phone book in the mobile phone and wants the diary and/or phone book in his/her PC to be updated with information from the mobile telephone.", "[0029] These functions are described, for example, in WO97/34403 and WO 98/11707.", "BRIEF DESCRIPTION OF THE DRAWINGS [0030] In the following, the invention will be described in more detail, by way of preferred embodiments and with reference to the drawings, in which: [0031] [0031 ]FIG. 1 is an overall schematic representation of the units according to the invention and how they interact;", "[0032] [0032 ]FIG. 2 is a schematic representation of a mobile telephone according to one embodiment of the invention;", "[0033] [0033 ]FIGS. 3A and 3B are flow charts of a first and a second embodiment of the method according to the invention.", "DETAILED DESCRIPTION OF EMBODIMENTS [0034] [0034 ]FIG. 1 is a schematic representation of the units according to the invention.", "In this example the method according to the invention is implemented for a building 1 , but it may just as well be an airplane, or the gate area at an airport, or any other area.", "[0035] In the building 1 , there are a number of mobile telephones 3 , 5 that may be used for mobile communication in mobile telephone networks, represented in the Figure by a base station 7 .", "This type of communication is well known in the art.", "The mobile telephones 3 may operate according to any standard known in the art, including Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), and Wideband CDMA.", "Accordingly the mobile terminals will not all connect to the same base station.", "Each mobile terminal will connect to a base station 7 in a network providing the appropriate standard.", "However, for simplicity, only one base station is shown in this figure, since the communication between the mobile telephones and the telephone networks is not essential to the invention.", "[0036] In the example, one mobile telephone 3 in the building 1 is currently involved in a connection to the base station 7 .", "Another mobile phone 5 is not involved in a connection, but is turned on.", "There may be other telephones in the building that are not turned on.", "These phones will not be affected by the invention, and are not shown.", "There are, of course, also a number of mobile telephones 9 outside the building.", "[0037] In the building 1 there is also a central radio unit 11 comprising a transmitter 13 transmitting low power radio signals.", "The power of the radio signals is adjusted so that the signal will be received by mobile telephones 3 , 5 inside the building, but not the mobile telephones 9 outside the building.", "[0038] The low power radio signal tells the mobile telephones 3 , 5 to respond by transmitting a similar signal to identify themselves to the central unit 11 , for example, by the type of equipment they are.", "This signal is received by a receiving part 15 and processed in a processor 17 in the central unit 11 .", "This identification is necessary, or at least desirable, to make sure that only equipment that really has to be turned off is, especially in the cases when an alert is sent out if all radio transmitting equipment is not turned off.", "For example, there is no need to turn off television sets or radios.", "The processor 17 also controls the transmitting and receiving parts 13 , 15 .", "[0039] In order for the method according to the invention to work, the mobile telephone must include a low power radio transmitter of the specified kind, and software for handling the functions, as will be described in connection with FIGS. 2 and 3.", "For mobile phones not including such units, a piece of additional equipment may be used to enable the mobile phone to communicate with the central radio unit.", "[0040] [0040 ]FIG. 2 shows a general mobile telephone 21 according to the invention.", "As an example, a GSM telephone is shown.", "[0041] The telephone shown in FIG. 2 comprises an antenna 27 used to receive and transmit signals through the air interface.", "The signals received by the antenna are processed in a radio unit 29 and a processing unit 31 before they are played to the subscriber through a loudspeaker 33 .", "The actual processing steps performed, such as demodulation, D/A conversion equalization and decoding, depend on the signalling system and are well known to the person skilled in the art.", "Speech is registered by a microphone 35 and processed by the processing unit 31 and the radio unit 29 before it is transmitted from the antenna 27 .", "As common in the art, the processor may also control a keyset and display (not shown).", "[0042] According to the invention, the telephone also comprises a short-range radio transmitter unit 37 , for example, a Bluetooth transmitter, controlled by the processing unit 31 .", "[0043] As discussed above, the short-range radio transmitter included in the mobile terminal according to the invention may, and probably will, be used for other purposes than that according to the invention.", "[0044] If the hardware and/or software needed for the method according to the invention is not included in the mobile terminal, a plug-in unit comprising the necessary hardware and software can instead be connected to the mobile telephone.", "[0045] [0045 ]FIG. 3A is a flow chart of the method according to a first embodiment of the invention: [0046] Step 101 : The central unit sends out a request signal requesting all mobile telephones and other units transmitting radio signals to identify themselves.", "[0047] Step 102 : Each radio transmitting unit, when receiving the signal from the central unit, identifies itself to the central unit by a response signal.", "This signal preferably includes the type of unit and the type or types of communication it may engage in.", "[0048] Step 103 : The central unit interprets each of the response signals received, and determines for each communication device that has responded, if this device has to be turned off or not, or to be partially turned off.", "[0049] Step 104 : If the device should be turned off, go to step 105 ;", "if an instruction or another message should be sent to the device , go to step 107 ;", "if nothing should happen, end of procedure.", "[0050] Step 105 : The central unit orders the device to turn itself off.", "[0051] Step 106 : The device turns itself off.", "The next time a request signal is sent out from the central unit, this device will not be registered.", "End of procedure.", "[0052] Step 107 : The central unit sends a message to the communication device.", "Any type of message that the device can handle may be sent, for example “turn of mobile phones”, or “switch to short distance radio for communication.”", "End of procedure.", "[0053] [0053 ]FIG. 3B is a flow chart of the method according to a second embodiment of the invention: [0054] Step 201 : The central unit sends out a request signal requesting all mobile telephones or other units transmitting radio signals to identify themselves.", "[0055] Step 202 : Each unit transmitting radio signals, when receiving the signal from the central unit, identifies itself to the central unit by a response signal.", "[0056] Step 203 : The central unit interprets each of the response signals received, and determines for each communication device that has responded, if this device has to be turned off or not.", "[0057] Step 204 : If the device should be turned off, go to step 205 ;", "if nothing should happen, end of procedure.", "[0058] Step 205 : The central unit orders the device to turn itself off.", "If the device offers several communication functions, for example, communication in a cellular network, which may be dangerous, and low power radio communication, only the undesired functions will have to be turned off, for example, the long-distance radio transmitting parts.", "[0059] Step 206 : The device transmits a confirmation signal to the central unit, then turns itself off.", "[0060] Step 207 : If confirmation signals are not received from all devices that should be turned off, within a certain amount of time, a message may be transmitted.", "This may be a private alert to the owner of the device that was not turned off, or a public alert or alarm.", "For example, in airplanes or in hospitals, a public alert may be appropriate to draw attention to the fact that electronic equipment may be disturbed.", "End of procedure." ]
CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a Divisional Application of U.S. patent application Ser. No. 11/206,484, filed Aug. 17, 2005, which is a Divisional Application of U.S. patent application Ser. No. 09/515,373, filed Feb. 29, 2000, which claims the benefit of U.S. Provisional Application No. 60/125,873, filed Mar. 24, 1999. TECHNICAL FIELD OF INVENTION [0002] The present invention relates to electrical stimulation of the retina to produce artificial images for the brain. It relates to electronic image stabilization techniques based on tracking the movements of the eye. It relates to telemetry in and out of the eye for uses such as remote diagnostics and recording from the retinal surface. [0003] The present invention also relates to electrical stimulation of the retina to produce phosphenes and to produce induced color vision. The present invention relates to hermetically sealed electronic and electrode units which are safe to implant in the eye. BACKGROUND [0004] Color perception is part of the fabric of human experience. Homer (c. 1100 b. c.) writes of “the rosy-fingered dawn”. Lady Murasaki no Shikibu (c. 1000 a.d.) uses word colors (“purple, yellow shimmer of dresses, blue paper”) in the world's first novel. In the early nineteenth century Thomas Young, an English physician, proposed a trichromatic theory of color vision, based on the action of three different retinal receptors. Fifty years later James Clerk Maxwell, the British physicist and Hermann von Helmholtz, the German physiologist, independently showed that all of the colors we see can be made up from three suitable spectral color lights. In 1964 Edward MacNichol and colleagues at Johns Hopkins and George Wald at Harvard measured the absorption by the visual pigments in cones, which are the color receptor cells. Rods are another type of photoreceptor cell in the primate retina. These cells are more sensitive to dimmer light but are not directly involved in color perception. The individual cones have one of three types of visual pigment. The first is most sensitive to short waves, like blue. The second pigment is most sensitive to middle wavelengths, like green. The third pigment is most sensitive to longer wavelengths, like red. [0005] The retina can be thought of a big flower on a stalk where the top of that stalk is bent over so that the back of the flower faces the sun. In place of the sun think of the external light focused by the lens of the eye onto the back of the flower. The cones and rods cells are on the front of the flower; they get the light which has passed through from the back of the somewhat transparent flower. The photoreceptor nerve cells are connected by synapses to bipolar nerve cells, which are then connected to the ganglion nerve cells. The ganglion nerve cells connect to the optic nerve fibers, which is the “stalk” that carries the information generated in the retina to the brain. Another type of retinal nerve cell, the horizontal cell, facilitates the transfer of information horizontally across bipolar cells. Similarly, another type of cell, the amacrine facilitates the horizontal transfer of information across the ganglion cells. The interactions among the retinal cells can be quite complex. On-center and off-center bipolar cells can be stimulated at the same time by the same cone transmitter release to depolarize and hyperpolarize, respectively. A particular cell's receptive field is that part of the retina, which when stimulated, will result in that cell's stimulation. Thus, most ganglion cells would have a larger receptive field than most bipolar cells. Where the response to the direct light on the center of a ganglion cells receptive field is antagonized by direct light on the surround of its receptive field, the effect is called center-surround antagonism. This phenomenon is important for detecting borders independent of the level of illumination. The existence of this mechanism for sharpening contrast was first suggested by the physicist Ernst Mach in the late 1800's. More detailed theories of color vision incorporate color opponent cells. On the cone level, trichromatic activity of the cone cells occurs. At the bipolar cell level, green-red opponent and blue-yellow opponent processing systems of the center-surround type, occur. For example, a cell with a green responding center would have a annular surround area, which responded in an inhibiting way to red. Similarly there can be red-center responding, green-surround inhibiting response. The other combinations involve blue and yellow in an analogous manner. [0006] It is widely known that Galvani, around 1780, stimulated nerve and muscle response electrically by applying a voltage on a dead frog's nerve. Less well known is that in 1755 LeRoy discharged a Leyden jar, i.e., a capacitor, through the eye of a man who had been blinded by the growth of a cataract. The patient saw “flames passing rapidly downward.” [0007] In 1958, Tassicker was issued a patent for a retinal prosthetic utilizing photosensitive material to be implanted subretinally. In the case of damage to retinal photoreceptor cells that affected vision, the idea was to electrically stimulate undamaged retinal cells. The photosensitive material would convert the incoming light into an electrical current, which would stimulate nearby undamaged cells. This would result in some kind of replacement of the vision lost. Tassicker reports an actual trial of his device in a human eye. (U.S. Pat. No. 2,760,483). [0008] Subsequently, Michelson (U.S. Pat. No. 4,628,933), Chow (U.S. Pat. Nos. 5,016,633; 5,397,350; 5,556,423), and De Juan (U.S. Pat. No. 5,109,844) all were issued patents relating to a device for stimulating undamaged retinal cells. Chow and Michelson made use of photodiodes and electrodes. The photodiode was excited by incoming photons and produced a current at the electrode. [0009] Normann et al. (U.S. Pat. No. 5,215,088) discloses long electrodes 1000 to 1500 microns long designed to be implanted into the brain cortex. These spire-shaped electrodes were formed of a semiconductor material. [0010] Najafi, et al., (U.S. Pat. No. 5,314,458), disclosed an implantable silicon-substrate based microstimulator with an external device which could send power and signal to the implanted unit by RF means. The incoming RF signal could be decoded and the incoming RF power could be rectified and used to run the electronics. [0011] Difficulties can arise if the photoreceptors, the electronics, and the electrodes all tend to be mounted at one place. One issue is the availability of sufficient area to accommodate all of the devices, and another issue is the amount of power dissipation near the sensitive retinal cells. Since these devices are designed to be implanted into the eye, this potential overheating effect is a serious consideration. [0012] Since these devices are implants in the eye, a serious problem is how to hermetically seal these implanted units. Of further concern is the optimal shape for the electrodes and for the insulators, which surround them. In one embodiment there is a definite need that the retinal device and its electrodes conform to the shape of the retinal curvature and at the same time do not damage the retinal cells or membranes. [0013] The length and structure of electrodes must be suitable for application to the retina, which averages about 200 microns in thickness. Based on this average retinal thickness of 200 microns, elongated electrodes in the range of 100 to 500 microns appear to be suitable. These elongated electrodes reach toward the cells to be activated. Being closer to the targeted cell, they require less current to activate it. [0014] In order not to damage the eye tissue there is a need to maintain an average charge neutrality and to avoid introducing toxic or damaging effects from the prosthesis. [0015] A desirable property of a retinal prosthetic system is making it possible for a physician to make adjustments on an on-going basis from outside the eye. One way of doing this would have a physician's control unit, which would enable the physician to make adjustments and monitor the eye condition. An additional advantageous feature would enable the physician to perform these functions at a remote location, e.g., from his office. This would allow one physician to remotely monitor a number of patients remotely without the necessity of the patient coming to the office. A patient could be traveling distantly and obtain physician monitoring and control of the retinal color prosthetic parameters. [0016] Another version of the physician's control unit is a hand-held, palm-size unit. This unit will have some, but not all of the functionality of the physician's control unit. It is for the physician to carry on his rounds at the hospital, for example, to check on post-operative retinal-prosthesis implant patients. Its extreme portability makes other situational uses possible, too, as a practical matter. [0017] The patient will want to control certain aspects of the visual image from the retinal prosthesis system, in particular, image brightness. Consequently, a patient controller, performing fewer functions than the physician's controller is included as part of the retinal prosthetic system. It will control, at a minimum, bright image, and it will control this image brightness in a continuous fashion. The image brightness may be increased or decreased by the patient at any time, under normal circumstances. [0018] A system of these components would itself constitute part of a visual prosthetic to form images in real time within the eye of a person with a damaged retina. In the process of giving back sight to those who are unable to see, it would be advantageous to supply artificial colors in this process of reconstructing sight so that the patient would be able to enjoy a much fuller version of the visual world. [0019] In dealing with externally mounted or externally placed means for capturing image and transmitting it by electronic means or other into the eye, one must deal with the problem of stabilization of the image. For example, a head-mounted camera would not follow the eye movement. It is desirable to track the eye movements relative to the head and use this as a method or approach to solving the image stabilization problem. [0020] By having a method and apparatus for the physician and the technician to initially set up and measure the internal activities and adjust these, the patient's needs can be better accommodated. The opportunity exists to measure internal activity and to allow the physician, using his judgment, to adjust settings and controls on the electrodes. Even the individual electrodes would be adjusted by way of the electronics controlling them. By having this done remotely, by remote means either by telephone or by the Internet or other such, it is clear that a physician would have the capability to intervene and make adjustment as necessary in a convenient and inexpensive fashion, to serve many patients. SUMMARY OF INVENTION [0021] The objective of the current invention is to restore color vision, in whole or in part, by electrically stimulating undamaged retinal cells, which remain in patients with lost or degraded visual function arising, for example, from Retinitis Pigmentosa or Age-Related Macular Degeneration. This invention is directed toward patients who have been blinded by degeneration of photoreceptors; but who have sufficient bipolar cells, or other cells acting similarly, to permit electrical stimulation. [0022] There are three main functional parts to this invention. One is external to the eye. The second part is internal to the eye. The third part is the communication circuitry for communicating between those two parts. Structurally there are two parts. One part is external to the eye and the other part in implanted within the eye. Each of these structural parts contains two way communication circuitry for communication between the internal and external parts. [0023] The structural external part is composed of a number of subsystems. These subsystems include an external imager, an eye-motion compensation system, a head motion compensation system, a video data processing unit, a patient's controller, a physician's local controller, a physician's remote controller, and a telemetry unit. The imager is a video camera such as a CCD or CMOS video camera. It gathers an image approximating what the eyes would be seeing if they were functional. [0024] The imager sends an image in the form of electrical signals to the video data processing unit. In one aspect, this unit formats a grid-like or pixel-like pattern that is then ultimately sent to electronic circuitry (part of the internal part) within the eye, which drives the electrodes. These electrodes are inside the eye. They replicate the incoming pattern in a useable form for stimulation of the retina so as to reproduce a facsimile of the external scene. In an other aspect of this invention other formats other than a grid-like or pixel like pattern are used, for example a line by line scan in some order, or a random but known order, point-by-point scan. Almost any one-to-one mapping between the acquired image and the electrode array is suitable, as long as the brain interprets the image correctly. [0025] The imager acquires color information. The color data is processed in the video data processing unit. The video data processing unit consists of microprocessor CPU's and associated processing chips including high-speed data signal processing (DSP) chips. [0026] In one aspect, the color information is encoded by time sequences of pulses separated by varying amounts of time; and, the pulse duration may be different for various pulses. The basis for the color encoding is the individual color code reference ( FIG. 2 a ). The electrodes stimulate the target cells so as to create a color image for the patient, corresponding to the original image as seen by the video camera, or other imaging means. [0027] Color information, in an alternative aspect, is sent from the video data processing unit to the electrode array, where each electrode has been determined to stimulate preferentially one of the bipolar cell types, namely, red-center green-surround, green-center-red-surround, blue-center-yellow-surround, or yellow-center-blue-surround. [0028] An eye-motion compensation system is an aspect of this invention. The eye tracker is based on detection of eye motion from the corneal reflex or from implanted coils of wire, or, more generally, insulated conductive coils, on the eye or from the measurement of electrical activity of extra-ocular muscles. Communication is provided between the eye tracker and the video data processing unit by electromagnetic or acoustical telemetry. In one embodiment of the invention, electromagnetic-based telemetry may be used. The results of detecting the eye movement are transmitted to a video data processing unit, together with the information from the camera means. Another aspect of the invention utilizes a head motion sensor and head motion compensation system. The video data processing unit can incorporate the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion. [0029] The internal structural part which is implanted internally within the eye, is also composed of a number of subsystems. These can be categorized as electronic circuits and electrode arrays, and communication subsystems, which may include electronic circuits. The circuits, the communication subsystems, and the arrays can be hermetically sealed and they can be attached one to the other by insulated wires. The electrode arrays and the electronic circuits can be on one substrate, or they may be on separate substrates joined by an insulated wire or by a plurality of insulated wires. This is similarly the case for a communication subsystem. [0030] A plurality of predominately electronic substrate units and a plurality of predominately electrode units may be implanted or located within the eye as desired or as necessary. The electrodes are designed so that they and the electrode insulation conform to the retinal curvature. The variety of electrode arrays include recessed electrodes so that the electrode array surface coming in contact with the retinal membrane or with the retinal cells is the non-metallic, more inert insulator. [0031] Another aspect of the invention is the elongated electrode, which is designed to stimulate deeper retinal cells by penetrating into the retina by virtue of the length of its electrodes. A plurality of electrodes is used. The elongated electrodes are of lengths from 100 microns to 500 microns. With these lengths, the electrode tips can reach through those retinal cells not of interest but closer to the target stimulation cells, the bipolar cells. The number of electrodes may range from 100 on up to 10,000 or more. With the development of electrode fabrication technology, the number of electrodes might rage up to one million or more. [0032] Another aspect of the invention uses a plurality of capacitive electrodes to stimulate the retina, in place of non-capacitive electrodes. Another aspect of the invention is the use of a neurotrophic factor, for example, Nerve Growth Factor, applied to the electrodes, or to the vicinity of the electrodes, to aid in attracting target nerves and other nerves to grow toward the electrodes. [0033] Hermetic sealing is accomplished by coating the object to be sealed with a substance selected from the group consisting of silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide, zirconium oxide. This hermetic sealing aspect of the invention provides an advantageous alternative to glass coverings for hermetic seals, being less likely to become damaged. [0034] Another feature of one aspect of the structural internal-to-the-eye subsystems is that the electronics receive and transmit information in coded or pulse form via electromagnetic waves. In the case where electromagnetic waves are used, the internal-to-the-eye implanted electronics can rectify the RF, or electromagnetic wave, current and decode it. The power being sent in through the receiving coil is extracted and used to drive the electronics. In some instances, the implanted electronics acquire data from the electrode units to transmit out to the video data processing unit. [0035] In another aspect the information coding is done with ultrasonic sound. An ultrasonic transducer replaces the electromagnetic wave receiving coil inside the eye. An ultrasonic transducer replaces the coil outside the eye for the ultrasonic case. By piezoelectric effects, the sound vibration is turned into electrical current, and energy extracted therefrom. [0036] In another aspect of the invention, information is encoded by modulating light. For the light modulation case, a light emitting diode (LED) or laser diode or other light generator, capable of being modulated, acts as the information transmitter. Information is transferred serially by modulating the light beam, and energy is extracted from the light signal after it is converted to electricity. A photo-detector, such as a photodiode, which turns the modulated light signal into a modulated electrical signal, is used as a receiver. [0037] Another aspect of the structural internal-to-the-eye subsystems of this invention is that the predominately electrode array substrate unit and the predominately electronic substrate unit, which are joined by insulated wires, can be placed near each other or in different positions. For example, the electrode array substrate unit can be placed subretinally and the electronic substrate unit placed epiretinally. On a further aspect of this invention, the electronic substrate unit can be placed distant from the retina so as to avoid generating additional heat or decreasing the amount of heat generated near the retinal nerve system. For example, the receiving and processing circuitry could be placed in the vicinity of the pars plana. In the case where the electronics and the electrodes are on the same substrate chip, two of these chips can be placed with the retina between them, one chip subretinal and the other chip epiretinal, such that the electrodes on each may be aligned. Two or more guide pins with corresponding guide hole or holes on the mating chip accomplish the alignment. Alternatively, two or more tiny magnets on each chip, each magnet of the correct corresponding polarity, may similarly align the sub- and epiretinal electrode bearing chips. Alternatively, corresponding parts which mate together on the two different chips and which in a fully mated position hold each other in a locked or “snap-together” relative position. [0038] Now as an element of the external-to-the-eye structural part of the invention, there is a provision for a physician's hand-held test unit and a physician's local or remote office unit or both for control of parameters such as amplitudes, pulse widths, frequencies, and patterns of electrical stimulation. [0039] The physician's hand-held test unit can be used to set up or evaluate and test the implant during or soon after implantation at the patient's bedside. It has, essentially, the capability of receiving what signals come out of the eye and having the ability to send information in to the retinal implant electronic chip. For example, it can adjust the amplitudes on each electrode, one at a time, or in groups. The hand-held unit is primarily used to initially set up and make a determination of the success of the retinal prosthesis. [0040] The physician's local office unit, which may act as a set-up unit as well as a test unit, acts directly through the video data processing unit. The remote physician's office unit would act over the telephone lines directly or through the Internet or a local or wide area network. The office units, local and remote, are essentially the same, with the exception that the physician's remote office unit has the additional communications capability to operate from a location remote from the patient. It may evaluate data being sent out by the internal unit of the eye, and it may send in information. Adjustments to the retinal color prosthesis may be done remotely so that a physician could handle a multiple number of units without leaving his office. Consequently this approach minimizes the costs of initial and subsequent adjustments. BRIEF DESCRIPTION OF THE DRAWINGS [0041] The above and other features and advantages of the invention will be more apparent from the following detailed description wherein: [0042] FIG. 1 a shows the general structural aspects of the retina color prosthesis system; [0043] FIG. 1 b shows the retina color prosthesis system with a structural part internal (to the eye), with an external part with subsystems for eye-motion feedback to enable maintaining a stable image presentation, and with a subsystems for communicating between the internal and external parts, and other structural subsystems; [0044] FIG. 1 c shows an embodiment of the retina color prosthesis system which is, in part, worn in eyeglass fashion; [0045] FIG. 1 d shows the system in FIG. 1 c in side view; [0046] FIG. 2 a shows an embodiment of the color I coding schemata for the stimulation of the sensation of color; [0047] FIG. 2 b represents an embodiment of the color I conveying method where a “large” electrode stimulates many bipolar cells with the color coding schemata of FIG. 2 a; [0048] FIG. 2 c represents an embodiment of the color II conveying method where an individual electrode stimulates a single type of bipolar cell; [0049] FIG. 3 a represents an embodiment of the telemetry unit including an external coil, an internal (to the eye) coil, and an internal electronic chip; [0050] FIG. 3 b represents an embodiment of the telemetry unit including an external coil, an internal (to the eye) coil, an external electronic chip, a dual coil transfer unit, and an internal electrode array; [0051] FIG. 3 c shows and acoustic energy and information transfer system; [0052] FIG. 3 d shows a light energy and information transfer system; [0053] FIG. 4 represents an embodiment of the external telemetry unit; [0054] FIG. 5 shows an embodiment of an internal telemetry circuit and electrode array switcher; [0055] FIG. 6 a shows a monopolar electrode arrangement and illustrates a set of round electrodes on a substrate material; [0056] FIG. 6 b shows a bipolar electrode arrangement; [0057] FIG. 6 c shows a multipolar electrode arrangement; [0058] FIG. 7 shows the corresponding indifferent electrode for monopolar electrodes; [0059] FIG. 8 a depicts the location of an epiretinal electrode array located inside the eye in the vitreous humor located above the retina, toward the lens capsule and the aqueous humor; [0060] FIG. 8 b shows recessed epiretinal electrodes where the electrically conducting electrodes are contained within the electrical insulation material; a silicon chip acts as a substrate; and the electrode insulator device is shaped so as to contact the retina in a conformal manner; [0061] FIG. 8 c is a rendering of an elongated epiretinal electrode array with the electrodes shown as pointed electrical conductors, embedded in an electrical insulator, where an pointed electrodes contact the retina in a conformal manner, however, elongated into the retina; [0062] FIG. 9 a shows the location of a subretinal electrode array below the retina, away from the lens capsule and the aqueous humor. The retina separates the subretinal electrode array from the vitreous humor; [0063] FIG. 9 b illustrates the subretinal electrode array with pointed elongated electrode, the insulator, and the silicon chip substrate where the subretinal electrode array is in conformal contact with the retina with the electrodes elongated to some depth; [0064] FIG. 10 a shows a iridium electrode that comprises a iridium slug, an insulator, and a device substrate where this embodiment shows the iridium slug electrode flush with the extent of the insulator; [0065] FIG. 10 b indicates an embodiment similar to that shown in FIG. 10 / 12 a , however, the iridium slug is recessed from the insulator along its sides, but with its top flush with the insulator; [0066] FIG. 10 c shows an embodiment with the iridium slug as in FIG. 10 / 12 b ; however, the top of the iridium slug is recessed below the level of the insulator; [0067] FIG. 10 d indicates an embodiment with the iridium slug coming to a point and insulation along its sides, as well as a being within the overall insulation structure; [0068] FIG. 10 e indicates an embodiment of a method for fabricating and the fabricated iridium electrode where on a substrate of silicon an aluminum pad is deposited; on the pad the conductive adhesive is laid and platinum or iridium foil is attached thereby; a titanium ring is placed, sputtered, plated, ion implanted, ion beam assisted deposited (IBAD) or otherwise attached to the platinum or iridium foil; silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide or other insulator will adhere better to the titanium while it would not adhere as well to the platinum or iridium foil; [0069] FIG. 11 a depicts a preferred electrode where it is formed on a silicon substrate and makes use of an aluminum pad, a metal foil such as platinum or iridium, conductive adhesive, a titanium ring, aluminum or zirconium oxide, an aluminum layer, and a mask; [0070] FIG. 11 b shows an elongated electrode formed on the structure of FIG. 11 a with platinum electroplated onto the metal foil, the mask removed and insulation applied over the platinum electrode; [0071] FIG. 11 c shows a variation of a form of the elongated electrode wherein the electrode is thinner and more recessed from the well sides; [0072] FIG. 11 d shows a variation of a form of the elongated electrode wherein the electrode is squatter but recessed from the well sides; [0073] FIG. 11 e shows a variation of a form of the elongated electrode wherein the electrode is a mushroom shape with the sides of its tower recessed from the well sides and its mushroom top above the oxide insulating material; [0074] FIG. 12 a shows the coil attachment to two different conducting pads at an electrode node; [0075] FIG. 12 b shows the coil attachment to two different conducting pads at an electrode node, together with two separate insulated conducting electrical pathways such as wires, each attached at two different electrode node sites on two different substrates; [0076] FIG. 12 c shows an arrangement similar to that seen in FIG. 12 / 16 d , with the difference that the different substrates are very close with a non-conducting adhesive between them and an insulator such as aluminum or zirconium oxide forms a connection coating over the two substrates, in part; [0077] FIG. 12 d depicts an arrangement similar to that seen in FIG. 12 / 16 c ; however, the connecting wires are replaced by an externally placed aluminum conductive trace; [0078] FIG. 13 shows a hermetically sealed flip-chip in a ceramic or glass case with solder ball connections to hermetically sealed glass frit and metal leads; [0079] FIG. 14 shows a hermetically sealed electronic chip as in FIG. 18 with the addition of biocompatible leads to pads on a remotely located electrode substrate; [0080] FIG. 15 shows discrete capacitors on the electrode-opposite side of an electrode substrate; [0081] FIG. 16 a shows an electrode-electronics retinal implant placed with the electrode half implanted beneath the retina, subretinally, while the electronics half projects above the retina, epiretinally; [0082] FIG. 16 b shows another form of sub- and epi-retinal implantation wherein half of the electrode implant is epiretinal and half is subretinal; [0083] FIG. 16 c shows the electrode parts are lined up by alignment pins or by very small magnets; [0084] FIG. 16 d shows the electrode part lined up by template shapes which may snap together to hold the parts in a fixed relationship to each other; [0085] FIG. 17 a shows the main screen of the physician's (local) controller (and programmer); [0086] FIG. 17 b illustrates the pixel selection of the processing algorithm with the averaging of eight surrounding pixels chosen as one element of the processing; [0087] FIG. 17 c represents an electrode scanning sequence, in this case the predefined sequence, A; [0088] FIG. 17 d shows electrode parameters, here for electrode B, including current amplitudes and waveform timelines; [0089] FIG. 17 e illustrates the screen for choosing the global electrode configuration, monopolar, bipolar, or multipolar; [0090] FIG. 17 f renders a screen showing the definition of bipolar pairs (of electrodes); [0091] FIG. 17 g shows the definition of the multipole arrangements; [0092] FIG. 18 a illustrates the main menu screen for the palm-sized test unit; [0093] FIG. 18 b shows a result of pressing on the stimulate bar of the main menu screen, where upon pressing the start button the amplitudes A 1 and A 2 are stimulated for times t 1 , t 2 , t 3 , and t 4 , until the stop button is pressed; [0094] FIG. 18 c exhibits a recording screen that shows the retinal recording of the post-stimulus and the electrode impedance; [0095] FIG. 19 a - c show the physician's remote controller that has the same functionality inside as the physician's controller but with the addition of communication means such as telemetry or telephone modem; and [0096] FIG. 20 shows the patient's controller unit. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0097] The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is merely made for the purpose of describing the general principles of the invention. The scope of the invention should be determined with reference to the claims. [0000] Objective [0098] The objective of the embodiments of the current invention is a retinal color prosthesis to restore color vision, in whole or in part, by electrically stimulating undamaged retinal cells, which remain in patients with, lost or degraded visual function. Embodiments of this retinal color prosthesis invention are directed toward helping patients who have been blinded by degeneration of photoreceptors and other cells; but who have sufficient bipolar cells and the like to permit the perception of color vision by electric stimulation. By color vision, it is meant to include black, gray, and white among the term color. [0000] General Description [0099] Functionally, there are three main parts to an embodiment of this retinal color prosthesis invention. See FIG. 1 a . FIG. 1 a is oriented toward showing the main structural parts and subsystems, with a dotted enclosure to indicate a functional intercommunications aspect. The first part of the embodiment is external ( 1 ) to the eye. The second part is implanted internal ( 2 ) to the eye. The third part is means for communication between those two parts ( 3 ). Structurally there are two parts. One part is external ( 1 ) to the eye and the other part ( 2 ) is implanted within the eye. Each of these structural parts contains two way communication circuitry for communication ( 3 ) between the internal ( 2 ) and external ( 1 ) parts. [0100] The external part of the retinal color prosthesis is carried by the patient. Typically, the external part including imager, video data processing unit, eye-tracker, and transmitter/receiver are worn as an eyeglass-like unit. Typical of this embodiment, a front view of one aspect of the structural external part ( 1 ) of the color retinal prosthesis is shown in FIG. 1 c and a side view is shown in FIG. 1 d , ( 1 ). In addition, there are two other units which may be plugged into the external unit; when this is done they act as part of the external unit. The physician's control unit is not normally plugged into the external part worn by the patient, except when the physician is conducting an examination and adjustment of the retinal color prosthetic. The patient's controller may or may not be normally plugged in. When the patient's controller is plugged in, it can also receive signals from a remote physician's controller which then acts in the same way as the plug-in physician's controller. [0101] Examining further the embodiment of the subsystems of the external part, see FIG. 1 b . These include an external color imager ( 111 ), an eye-motion compensation system ( 112 ), a head-motion compensation system ( 131 ), a processing unit ( 113 ), a patient's controller ( 114 ), a physician's local controller ( 115 ), a physicians hand-held palm-size pocket-size unit ( 130 ), a physician's remote controller ( 117 ), and a telemetry means ( 118 ). The color imager is a color video camera such as a CCD or CMOS video camera. It gathers an image approximating what the eyes would be seeing if they were functional. [0102] An external imager ( 111 ) sends an image in the form of electrical signals to the video data processing unit ( 113 ). The video data processing unit consists of microprocessor CPU's and associated processing chips including high-speed data signal processing (DSP) chips. This unit can format a grid-like or pixel-like pattern that is sent to the electrodes by way of the telemetry communication subsystems ( 118 , 121 ). See FIG. 1 b . In this embodiment of the retinal color prosthesis ( FIG. 1 b , ( 121 )), these electrodes are incorporated in the internal-to-the eye implanted part. [0103] These electrodes, which are part of the internal implant ( 121 ), together with the telemetry circuitry ( 121 ) are inside the eye. With other internally implanted electronic circuitry ( 121 ), they cooperate with the electrodes so as to replicate the incoming pattern, in a useable form, for stimulation of the retina so as to reproduce a facsimile perception of the external scene. The eye-motion ( 112 ) and head-motion ( 131 ) detectors supply information to the video data processing unit ( 113 ) to shift the image presented to the retina ( 120 ). [0104] There are three preferred embodiments for stimulating the retina via the electrodes to convey the perception of color. Color information is acquired by the imaging means ( 111 ). The color data is processed in the video data processing unit ( 113 ). [0000] First Preferred Color Mode [0105] Color information (See FIG. 2 a ), in the first preferred embodiment, is encoded by time sequences of pulses ( 201 ) separated by varying amounts of time ( 202 ), and also with the pulse duration being varied in time ( 203 ). The basis for the color encoding is the individual color code reference ( 211 through 217 ). The electrodes stimulate the target cells so as to create a color image for the patient, corresponding to the original image as seen by the video camera, or other imaging means. Using temporal coding of electrical stimuli placed (cf. FIG. 2 b , 220 , FIG. 2 c , 230 ) on or near the retina ( FIG. 2 b and FIG. 2 c , 221 , 222 ) the perception of color can be created in patients blinded by outer retinal degeneration. By sending different temporal coding schemes to different electrodes, an image composed of more than one color can be produced. FIG. 2 shows one stimulation protocol. Cathodic stimuli ( 202 ) are below the zero plane ( 220 ) and anodic stimuli ( 203 ) are above. All the stimulus rates are either “fast” ( 203 ) or “slow” ( 202 ) except for green ( 214 ), which includes an intermediate stimulus rate ( 204 ). The temporal codes for the other colors are shown as Red ( 211 ), as Magenta ( 212 ), as Cyan ( 213 ), as Yellow ( 215 ), as Blue ( 216 ), as Neutral ( 217 ). This preferred embodiment is directed toward electrodes which are less densely packed in proximity to the retinal cells. [0000] Second Preferred Color Mode [0106] Color information, in a second preferred embodiment, is sent from the video data processing unit to the electrode array, where each electrode has been determined by test to stimulate one of a bipolar type: red-center green-surround, green-center-red-surround, blue-center-yellow-surround, or yellow-center-blue-surround. In this embodiment, electrodes which are small enough to interact with a single cell, or at most, a few cells are placed in the vicinity of individual bipolar cells, which react to a stimulus with nerve pulse rates and nerve pulse structure (i.e., pulse duration and pulse amplitude). Some of the bipolar cells, when electrically, or otherwise, stimulated, will send red-green signals to the brain. Others will send yellow-blue signals. This refers to the operation of the normal retina. In the normal retina, red or green color photoreceptors (cone cells) send nerve pulses to the red-green bipolar cell which then pass some form of this information up to the ganglion cells and then up to the visual cortex of the brain. With small electrodes individual bipolar cells can be excited in a spatial, or planar, pattern. Small electrodes are those with tip from 0.1 μm to 15 μm, and which individual electrodes are spaced apart from a range 8 μm to 24 μm, so as to approximate a one-to-one correspondence with the bipolar cells. The second preferred embodiment is oriented toward a more densely packed set of electrodes. [0000] Third Preferred Color Mode [0107] A third preferred mode is a combination of the first and of the second preferred modes such that a broader area coverage of the color information encoded by time sequences of pulses, of varying widths and separations and with relatively fewer electrodes is combined with a higher density of electrodes, addressing more the individual bipolar cells. [0000] First Order and Higher Effects [0108] Regardless of a particular theory of color vision, the impinging of colored light on the normal cones, and possibly rods, give rise in some fashion to the perception of color, i.e., multi-spectral vision. In the time-pulse coding color method, above, the absence of all, or sufficient, numbers of working cones (and rods) suggests a generalization of the particular time-pulse color encoding method. The generalization is based on the known, or partly known, neuron conduction pathways in the retina. The cone cells, for example, signal to bipolar cells, which in turn signal the ganglion cells. The original spatial-temporal-color (including black, white) scheme for conveying color information as the cone is struck by particular wavelength photons is then transformed to a patterned signal firing of the next cellular level, say the bipolar cells, unless the cones are absent or don't function. Thus, this second level of patterned signal firing is what one wishes to supply to induce the perception of color vision. [0109] The secondary layer of patterned firing may be close to the necessary primary pattern, in which case the secondary pattern (S) may be represented as P*(1+ε). The * indicates matrix multiplication. P is the primary pattern, represented as a matrix P= [ p 11 p 1 ⁢ j p k ⁢   ⁢ 1 p kj ]   where P represents the light signals of a particular spatial-temporal pattern, e.g., flicker signals for green. The output from the first cell layer, say the cones, is then S, the secondary pattern. This represents the output from the bipolar layer in response to the input from the first (cone) layer. If S=P*(1+ε), where 1 represents a vector and E represents a small deviation applied to the vector 1, then S is represented by P to the lowest order, and by P*(1+ε) to the next order. Thus, the response may be seen as a zero order effect and a first order linear effect. Additional terms in the functional relationship are included to completely define the functional relationship. If S is some non-linear function of P, finding S by starting with P requires more terms then the linear case to define the bulk of the functional relationship. However, regardless of the details of one color vision theory or another, on physiological grounds S is some function of P. As in the case of fitting individual patients with lenses for their glasses, variations of parameters are expected in fitting each patient to a particular temporal coding of electrical stimuli. Scaling Data from Photoreceptors to Bipolar Cells [0110] As cited above, Greenberg (1998), indicates that electrical and photic stimulation of the normal retina operate via similar mechanisms. Thus, even though electrical stimulation of a retina damaged by outer retinal degeneration is different from the electrical stimulation of a normal retina, the temporal relationships are expected to be analogous. [0111] To explain this, it is noted that electrical stimulation of the normal retinal is accomplished by stimulating the photoreceptor cells (including the color cells activated differentially according to the color of light impinging on them). For the outer retinal degeneration, it is precisely these photoreceptor cells which are missing. Therefore, the electrical stimulation in this case proceeds by way of the cells next up the ladder toward the optic nerve, namely, the bipolar cells. [0112] The time constant for stimulating photoreceptor is about 20 milliseconds. Thus the electrical pulse duration would need to be at least 20 milliseconds. The time constant for stimulating bipolar cells is around 9 seconds. These time constants are much longer than for the ganglion cells (about 1 millisecond). The ganglion cells are another layer of retinal cells closer to the optic nerve. The actual details of the behavior of the different cell types of the retina are quite complicated including the different relationships for current threshold versus stimulus duration (cf. Greenberg, 1998). One may, however, summarize an apparent resonant response of the cells based on their time constants corresponding to the actual pulse stimulus duration. [0113] In FIG. 2 , which is extrapolated from external-to-the-eye electrical stimulation data of Young (1977) and from light stimulation data of Festinger, Allyn, and White (1971), there is shown data that would be applicable to the photoreceptor cells. One may scale the data down based on the ratio of the photoreceptor time constant (about 20 milliseconds) to that of the bipolar cells (about 9 milliseconds). Consequently, 50 milliseconds on the time scale in FIG. 2 now corresponds to 25 milliseconds. Advantageously, stimulation rates and duration of pulses, as well as pulse widths may be chosen which apply to the electrode stimulation of the bipolar cells of the retina. [0000] Eye Movement/Head Motion Compensation [0114] In a preferred embodiment, an external imager such as a color CCD or color CMOS video camera ( 111 ) and a video data processing unit ( 113 ), with an external telemetry unit ( 118 ) present data to the internal eye-implant part. Another aspect of the preferred embodiment is a method and apparatus for tracking eye movement ( 112 ) and using that information to shift ( 113 ) the image presented to the retina. Another aspect of the preferred embodiment utilizes a head motion sensor ( 131 ) and a head motion compensation system ( 131 , 113 ). The video data processing unit incorporates the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion. Thus electronic image compensation, stabilization and adjustment are provided by the eye and head movement compensation subsystems of the external part of the retinal color prosthesis. [0000] Logarithmic Encoding of Light [0115] In one aspect of an embodiment ( FIG. 1 b ), light amplitude is recorded by the external imager ( 111 ). The video data processing unit uses a logarithmic encoding scheme ( 113 ) to convert the incoming light amplitudes into the logarithmic electrical signals of these amplitudes ( 113 ). These electrical signals are then passed on by telemetry ( 118 ), ( 121 ), to the internal implant ( 121 ) which results in the retinal cells ( 120 ) being stimulated via the implanted electrodes ( 121 ), in this embodiment as part of the internal implant ( 121 ). Encoding is done outside the eye, but may be done internal to the eye, with a sufficient internal computational capability. [0000] Energy and Signal Transmission [0000] Coils [0116] The retinal prosthesis system contains a color imager ( FIG. 1 b , 111 ) such as a color CCD or CMOS video camera. The imaging output data is typically processed ( 113 ) into a pixel-based format compatible with the resolution of the implanted system. This processed data ( 113 ) is then associated with corresponding electrodes and amplitude and pulse-width and frequency information is sent by telemetry ( 118 ) into the internal unit coils, ( 311 ), ( 313 ), ( 314 ) (see FIG. 3 a ). Electromagnetic energy, is transferred into and out from an electronic component ( 311 ) located internally in the eye ( 312 ), using two insulated coils, both located under the conjunctiva of the eye with one free end of one coil ( 313 ) joined to one free end of the second coil ( 314 ), the second free end of said one coil joined to the second free end of said second coil. The second coil ( 314 ) is located in proximity to a coil ( 311 ) which is a part of said internally located electronic component, or, directly to said internally located electronic component ( 311 ). The larger coil is positioned near the lens of the eye. The larger coil is fastened in place in its position near the lens of the eye, for example, by suturing. FIG. 3 b represents an embodiment of the telemetry unit temporally located near the eye, including an external temporal coil ( 321 ), an internal (to the eye) coil ( 314 ), an external-to-the-eye electronic chip ( 320 ), dual coil transfer units ( 314 , 323 ), ( 321 , 322 ) and an internal-to-the-eye electrode array ( 325 ). The advantage of locating the external electronics in the fatty tissue behind the eye is that there is a reasonable amount of space there for the electronics and in that position it appears not to interfere with the motion of the eye. [0000] Ultrasonic Sound [0117] In another aspect the information coding is done with ultrasonic sound and in a third aspect information is encoded by modulating light. An ( FIG. 3 c ) ultrasonic transducer ( 341 ) replaces the electromagnetic wave receiving coil on the implant ( 121 ) inside the eye. An ultrasonic transducer ( 342 ) replaces the coil outside the eye for the ultrasonic case. A transponder ( 343 ) under the conjunctiva of the eye may be used to amplify the acoustic signal and energy either direction. By piezoelectric effects, the sound vibration is turned into electrical current, and energy extracted therefrom. [0000] Modulated Light Beam [0118] For the light modulation ( FIG. 3 d ) case, a light emitting diode (LED) or laser diode or other light generator ( 361 ), capable of being modulated, acts as the information transmitter. Information is transferred serially by modulating the light beam, and energy is extracted from the light signal after it is converted to electricity. A photo-detector ( 362 ), such as a photodiode, which turns the modulated light signal into a modulated electrical signal, is used as a receiver. A set of a photo-generator and a photo-detector are on the implant ( 121 ) and a set is also external to the eye [0000] Prototype-Like Device [0119] FIG. 4 shows an example of the internal-to-the-eye and the external-to-the eye parts of the retinal color prosthesis, together with a means for communicating between the two. The video camera ( 401 ) connects to an amplifier ( 402 ) and to a microprocessor ( 403 ) with memory ( 404 ). The microprocessor is connected to a modulator ( 405 ). The modulator is connected to a coil drive circuit ( 406 ). The coil drive circuit is connected to an oscillator ( 407 ) and to the coil ( 408 ). The coil ( 408 ) can receive energy inductively, which can be used to recharge a battery ( 410 ), which then supplies power. The battery may also be recharged from a charger ( 409 ) on a power line source ( 411 ). [0120] The internal-to-the eye implanted part shows a coil ( 551 ), which connects to both a rectifier circuit ( 552 ) and to a demodulator circuit ( 553 ). The demodulator connects to a switch control unit ( 554 ). The rectifier ( 552 ) connects to a plurality of diodes ( 555 ) which rectify the current to direct current for the electrodes ( 556 ); the switch control sets the electrodes as on or off as they set the switches ( 557 ). The coils ( 408 ) and ( 551 ) serve to connect inductively the internal-to-the-eye ( 500 ) subsystem and the external-to-the patient ( 400 ) subsystem by electromagnetic waves. Both power and information can be sent into the internal unit. Information can be sent out to the external unit. Power is extracted from the incoming electromagnetic signal and may be accumulated by capacitors connected to each electrode or by capacitive electrodes themselves. [0000] Simple Electrode Implant [0121] FIG. 6 a illustrates a set of round monopolar electrodes ( 602 ) on a substrate material ( 601 ). FIG. 7 shows the corresponding indifferent electrode ( 702 ) for these monopolar electrodes, on a substrate ( 701 ), which may be the back of ( 601 ). FIG. 6 b shows a bipolar arrangement of electrodes, both looking down onto the plane of the electrodes, positive ( 610 ) and negative ( 611 ), and also looking at the electrodes sideways to that view, positive ( 610 ) and negative ( 611 ), sitting on their substrate ( 614 ). Similarly for FIG. 6 c where a multipole triplet is shown, with two positive electrodes ( 621 ) and one negative electrode, looking down on their substrate plane, and looking sideways to that view, also showing the substrate ( 614 ). [0000] Epiretinal Electrode Array [0122] FIG. 8 a depicts the location of an epiretinal electrode array ( 811 ) located inside the eye ( 812 ) in the vitreous humor ( 813 ) located above the retina ( 814 ), toward the lens capsule ( 815 ) and the aqueous humor ( 816 ); [0123] One aspect of the present embodiment, shown in FIG. 8 b , is the internal retinal color prosthetic part, which has electrodes ( 817 ) which may be flat conductors that are recessed in an electrical insulator ( 818 ). One flat conductor material is a biocompatible metallic foil ( 817 ). Platinum foil is a particular type of biocompatible metal foil. The electrical insulator ( 818 ) in one aspect of the embodiment is silicone. [0124] The silicone ( 818 ) is shaped to the internal curvature of the retina ( 814 ). The vitreous humor ( 813 ), the conductive solution naturally present in the eye, becomes the effective electrode since the insulator ( 818 ) confines the field lines in a column until the current reaches the retina ( 814 ). A further advantage of this design is that the retinal tissue ( 814 ) is only in contact with the insulator ( 818 ), such as silicone, which may be more inactive, and thus, more biocompatible than the metal in the electrodes. Advantageously, another aspect of an embodiment of this invention is that adverse products produced by the electrodes ( 817 ) are distant from the retinal tissue ( 814 ) when the electrodes are recessed. [0125] FIG. 8 c shows elongated epiretinal electrodes ( 820 ). The electrically conducting electrodes ( 820 ) says are contained within the electrical insulation material ( 818 ); a silicon chip ( 819 ) acts as a substrate. The electrode insulator device ( 818 ) is shaped so as to contact the retina ( 814 ) in a conformal manner. [0000] Subretinal Electrode Array [0126] FIG. 9 a shows the location of a subretinal electrode array ( 811 ) below the retina ( 814 ), away from the lens capsule ( 815 ) and the aqueous humor ( 816 ). The retina ( 814 ) separates the subretinal electrode array from the vitreous humor ( 813 ). FIG. 9 b illustrates the subretinal electrode array ( 811 ) with pointed elongated electrodes ( 817 ), the insulator ( 818 ), and the silicon chip ( 819 ) substrate. The subretinal electrode array ( 811 ) is in conformal contact with the retina ( 814 ) with the electrodes ( 817 ) elongated to some depth. [0000] Electrodes [0000] Iridium Electrodes [0127] Now FIG. 10 will illuminate structure and manufacture of iridium electrodes ( FIGS. 10 a - e ). FIG. 10 a shows an iridium electrode, which comprises an iridium slug ( 1011 ), an insulator ( 1012 ), and a device substrate ( 1013 ). This embodiment shows the iridium slug electrode flush with the extent of the insulator. FIG. 10 b indicates an embodiment similar to that shown in FIG. 10 a , however, the iridium slug ( 1011 ) is recessed from the insulator ( 1012 ) along its sides, but with its top flush with the insulator. When the iridium electrodes ( 1011 ) are recessed in the insulating material ( 1012 ), they may have the sides exposed so as to increase the effective surface area without increasing geometric area of the face of the electrode. If an electrode ( 1011 ) is not recessed it may be coated with an insulator ( 1012 ), on all sides, except the flat surface of the face ( 1011 ) of the electrode. Such an arrangement can be embedded in an insulator that has an overall profile curvature that follows the curvature of the retina. The overall profile curvature may not be continuous, but may contain recesses, which expose the electrodes. [0128] FIG. 10 c shows an embodiment with the iridium slug as in FIG. 10 b , however, the top of the iridium slug ( 1011 ) is recessed below the level of the insulator; FIG. 10 d indicates an embodiment with the iridium slug ( 1011 ) coming to a point and insulation along its sides ( 1021 ), as well as a being within the overall insulation structure ( 1021 ). FIG. 10 e indicates an embodiment of a method for fabricating the iridium electrodes. On a substrate ( 1013 ) of silicon, an aluminum pad ( 1022 ) is deposited. On the pad the conductive adhesive ( 1023 ) is laid and platinum or iridium foil ( 1024 ) is attached thereby. A titanium ring ( 1025 ) is placed, sputtered, plated, ion implanted, ion beam assisted deposited (IBAD) or otherwise attached to the platinum or iridium foil ( 1024 ). Silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1012 ) or other insulator can adhere better to the titanium ( 1025 ) while it would not otherwise adhere as well to the platinum or iridium foil ( 1024 ). The depth of the well for the iridium electrodes ranges from 0.1 μm to 1 mm. [0000] Elongated Electrodes [0129] Another aspect of an embodiment of the invention is the elongated electrode, which are designed to stimulate deeper retinal cells, in one embodiment, by penetrating the retina. By getting closer to the target cells for stimulation, the current required for stimulation is lower and the focus of the stimulation is more localized. The lengths chosen are 100 microns through 500 microns, including 300 microns. FIG. 8 c is a rendering of an elongated epiretinal electrode array with the electrodes shown as pointed electrical conductors ( 820 ), embedded in an electrical insulator ( 818 ), where the elongated electrodes ( 817 ) contact the retina in a conformal manner, however, penetrating into the retina ( 814 ). [0130] These elongated electrodes, in an aspect of this of an embodiment of the invention may be of all the same length. In a different aspect of an embodiment, they may be of different lengths. Said electrodes may be of varying lengths ( FIG. 8, 817 ), such that the overall shape of said electrode group conforms to the curvature of the retina ( 814 ). In either of these cases, each may penetrate the retina from an epiretinal position ( FIG. 8 a , 811 ), or, in a different aspect of an embodiment of this invention, each may penetrate the retina from a subretinal position ( FIG. 9 b , 817 ). [0131] One method of making the elongated electrodes is by electroplating with one of an electrode material, such that the electrode, after being started, continuously grows in analogy to a stalagmite or stalactite. The elongated electrodes are 100 to 500 microns in length, the thickness of the retina averaging 200 microns. The electrode material is a substance selected from the group consisting of pyrolytic carbon, titanium nitride, platinum, iridium oxide, and iridium. The insulating material for the electrodes is a substance selected from the group silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide. [0000] Platinum Electrodes [0132] FIG. 11 ( a - e ) demonstrates a preferred structure of, and method of, making, spiked and mushroom platinum electrodes. Examining FIG. 11 a one sees that the support for the flat electrode ( 1103 ) and other components such as electronic circuits (not shown) is the silicon substrate ( 1101 ). An aluminum pad ( 1102 ) is placed where an electrode or other component is to be placed. In order to hermetically seal-off the aluminum and silicon from any contact with biological activity, a metal foil ( 1103 ), such as platinum or iridium, is applied to the aluminum pad ( 1102 ) using conductive adhesive ( 1104 ). Electroplating is not used since a layer formed by electroplating, in the range of the required thinness, has small-scale defects or holes which destroy the hermetic character of the layer. A titanium ring ( 1105 ) is next placed on the platinum or iridium foil ( 1103 ). Normally, this placement is by ion implantation, sputtering or ion beam assisted deposition (IBAD) methods. Silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1106 ) is placed on the silicon substrate ( 1101 ) and the titanium ring ( 1105 ). In one embodiment, an aluminum layer ( 1107 ) is plated onto exposed parts of the titanium ring ( 1105 ) and onto the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1106 ). In this embodiment the aluminum ( 1107 ) layer acts as an electrical conductor. A mask ( 1108 ) is placed over the aluminum layer ( 1107 ). [0133] In forming an elongated, non-flat, electrode ( FIG. 11 b ), platinum is electroplated onto the platinum or iridium foil ( 1103 ). Subsequently, the mask ( 1108 ) is removed and insulation ( 1110 ) is applied over the platinum electrode ( 1109 ). [0134] In FIG. 11 c , a platinum electrode ( 1109 ) is shown which is more internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring. The electrode ( 1109 ) is also thinner and more elongated and more pointed. FIG. 11 d shows a platinum electrode formed by the same method as was used in FIGS. 11 a , 11 b , and 11 c . The platinum electrode ( 1192 ) is more internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring as was the electrode ( 109 ) in FIG. 11 c . However it is less elongated and less pointed. [0135] The platinum electrode is internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring; said electrode whole angle at it's peak being in the range from 1° to 120°; the base of said conical or pyramidal electrode ranging from 1 micron to 500 micron; the linear section of the well unoccupied by said conical or pyramidal electrode ranging from zero to one-third. [0136] A similar overall construction is depicted in FIG. 1 e . The electrode ( 1193 ), which may be platinum, is termed a mushroom shape. The maximum current density for a given metal is fixed. The mushroom shape presents a relatively larger area than a conical electrode of the same height. The mushroom shape advantageously allows a higher current, for the given limitation on the current density (e.g., milliamperes per square millimeter) for the chosen electrode material, since the mushroom shape provides a larger area. [0000] Inductive Coupling Coils [0137] Information transmitted electromagnetically into or out of the implanted retinal color prosthesis utilizes insulated conducting coils so as to allow for inductive energy and signal coupling. FIG. 12 b shows an insulated conducting coil and insulated conducting electrical pathways, e.g., wires, attached to substrates at what would otherwise be electrode nodes, with flat, recessed metallic, conductive electrodes ( 1201 ). In referring to wire or wires, insulated conducting electrical pathways are included, such as in a “two-dimensional” “on-chip” coil or a “two-dimensional” coil on a polyimide substrate, and the leads to and from these “two-dimensional” coil structures. A silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1204 ) is shown acting as both an insulator and an hermetic seal. Another aspect of the embodiment is shown in FIG. 12 d . The electrode array unit ( 1201 ) and the electronic circuitry unit ( 1202 ) can be on one substrate, or they may be on separate substrates ( 1202 ) joined by an insulated wire or by a plurality of insulated wires ( 1203 ). Said separate substrate units can be relatively near one another. For example, they might lie against a retinal surface, either epiretinally or subretinally placed. Two substrates units connected by insulated wires may carry more electrodes than if only one substrate with electrodes was employed, or it might be arranged with one substrate carrying the electrodes, the other the electronic circuitry. Another arrangement has the electrode substrate or substrates placed in a position to stimulate the retinal cells, while the electronics are located closer to the lens of the eye to avoid heating the sensitive retinal tissue. [0138] In all of the FIGS. 12 a , 12 b , and 12 c , a coil ( 1205 ) is shown attached by an insulated wire. The coil can be a coil of wire, or it can be a “two dimensional” trace as an “on-chip” component or as a component on polyimide. This coil can provide a stronger electromagnetic coupling to an outside-the-eye source of power and of signals. FIG. 12 c shows an externally placed aluminum (conductive) trace instead of the electrically conducting wire of FIG. 12 d . Also shown is an electrically insulating adhesive ( 1208 ) which prevents electrical contact between the substrates ( 1202 ) carrying active circuitry ( 1209 ). [0000] Hermetic Sealing [0000] Hermetic Coating [0139] All structures, which are subject to corrosive action as a result of being implanted in the eye, or, those structures which are not completely biocompatible and not completely safe to the internal cells and fluids of the eye require hermetic sealing. Hermetic sealing may be accomplished by coating the object to be sealed with silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide. These materials also provide electrical insulation. The method and apparatus of hermetic sealing by aluminum and zirconium oxide coating is described in a pending U.S. patent application Ser. No. 08/994,515, now U.S. Pat. No. 6,043,437. The methods of coating a substrate material with the hermetic sealant include sputtering, ion implantation, and ion-beam assisted deposition (IBAD). [0000] Hermetic Box [0140] Another aspect of an embodiment of the invention is hermetically sealing the silicon chip ( 1301 ) by placing it in a metal or ceramic box ( 1302 ) of rectangular cross-section with the top and bottom sides initially open ( FIG. 13 ). The box may be of one ( 1302 ) of the metals selected from the group comprising platinum, iridium, palladium, gold, and stainless steel. Solder balls ( 1303 ) are placed on the “flip-chip”, i.e., a silicon-based chip that has the contacts on the bottom of the chip ( 1301 ). Metal feedthroughs ( 1304 ) made from a metal selected from the group consisting of radium, platinum, titanium, iridium, palladium, gold, and stainless steel. The bottom cover ( 1306 ) is formed from one of the ceramics selected from the group consisting of aluminum oxide or zirconium oxide. The inner surface ( 1305 ), toward the solder ball, ( 1303 )) of the feed-through ( 1304 ) is plated with gold or with nickel. The ceramic cover ( 1306 ) is then attached to the box using a braze ( 1307 ) selected from the group consisting of: 50% titanium together with 50% nickel and gold. Electronics are then inserted and the metal top cover (of the same metal selected for the box) is laser welded in place. [0000] Separate Electronics Chip Substrate and Electrode Substrate [0141] In one embodiment of the invention ( FIG. 14 ), the chip substrate ( 1401 ) is hermetically sealed in a case ( 1402 ) or by a coating of the aluminum, zirconium, or magnesium oxide coating. However, the electrodes ( 1403 ) and its substrate ( 1404 ) form a distinct and separate element. Insulated and hermetically sealed wires ( 1405 ) connect the two. The placement of the electrode element may be epiretinal, while the electronic chip element may be relatively distant from the electrode element, as much distant as being in the vicinity of the eye lens. Another embodiment of the invention has the electrode element placed subretinally and the electronic chip element placed toward the rear of the eye, being outside the eye, or, being embedded in the sclera of the eye or in or under the choroid, blood support region for the retina. Another embodiment of the invention has the electronic chip element implanted in the fatty tissue behind the eye and the electrode element placed subretinally or epiretinally. [0000] Capacitive Electrodes [0142] A plurality of capacitive electrodes can be used to stimulate the retina, in place of non-capacitive electrodes. A method of fabricating said capacitive electrode uses a pair of substances selected from the pair group consisting of the pairs iridium and iridium oxide; and, titanium and titanium nitride. The metal electrode acts with the insulating oxide or nitride, which typically forms of its own accord on the surface of the electrode. Together, the conductor and the insulator form an electrode with capacitance. [0143] Mini-capacitors ( FIG. 15 ) can also be used to supply the required isolating capacity. The capacity of the small volume size capacitors ( 1501 ) is 0.47 microfarads. The dimensions of these capacitors are individually 20 mils (length) by 20 mils (width) by 40 mils (height). In one embodiment of the invention, the capacitors are mounted on the surface of a chip substrate ( 1502 ), that surface being opposite to the surface containing the active electronics elements of the chip substrate. [0000] Electrode/Electronics Component Placement [0144] In one embodiment ( FIG. 16 a ), the internal-to-the-eye implanted part consists of two subsystems, the electrode component subretinally positioned and the electronic component epiretinally positioned. The electronics component, with its relatively high heat dissipation, is positioned at a distance, within the eye, from the electrode component placed near the retina that is sensitive to heat. [0145] An alternative embodiment shown in FIG. 16 b is where one of the combined electronic and electrode substrate units is positioned subretinally and the other is located epiretinally and both are held together across the retina so as to efficiently stimulate bipolar and associated cells in the retina. [0146] An alternative embodiment of the invention has the electronic chip element implanted in the fatty tissue behind the eye and the electrode element placed subretinally or epiretinally, and power and signal communication between them by electromagnetic means including radio-frequency (RF), optical, and quasi-static magnetic fields, or by acoustic means including ultrasonic transducers. [0147] FIG. 16 c shows how the two electronic-electrode substrate units are held positioned in a prescribed relationship to each other by small magnets. Alternatively the two electronic-electrode substrate units are held in position by alignment pins. Another aspect of this is to have the two electronic-electrode substrate units held positioned in a prescribed relationship to each other by snap-together mating parts, some exemplary ones being shown in FIG. 16 d. [0000] Neurotrophic Factor [0148] Another aspect of the embodiment is the use of a neurotrophic factor, for example, Nerve Growth Factor, applied to the electrodes, or to the vicinity of the electrodes, to aid in attracting target nerves and other nerves to grow toward the electrodes. [0000] Eye-Motion Compensation System [0149] Another aspect of the embodiment is an eye-motion compensation system comprising an eye-movement tracking apparatus ( FIG. 1 b , 112 ); measurements of eye movement; a transmitter to convey said measurements to video data processor unit that interprets eye movement measurements as angular positions, angular velocities, and angular accelerations; and the processing of eye position, velocity, acceleration data by the video data processing unit for image compensation, stabilization and adjustment. [0150] Ways of eye-tracking ( FIG. 1 b , 112 ) include utilizing the corneal eye reflex, utilizing an apparatus for measurements of electrical activity where one or more coils are located on the eye and one or more coils are outside the eye, utilizing an apparatus where three orthogonal coils placed on the eye and three orthogonal coils placed outside the eye, utilizing an apparatus for tracking movements where electrical recordings from extra-ocular muscles are measured and conveyed to the video data processing unit that interprets such electrical measurements as angular positions, angular velocities, and angular accelerations. The video data processing unit uses these values for eye position, velocity, acceleration to compute image compensation, stabilization and adjustment data which is then applied by the video data processor to the electronic form of the image. [0000] Head Sensor [0151] Another aspect of the embodiment utilizes a head motion sensor ( 131 ). The basic sensor in the head motion sensor unit is an integrating accelerometer. A laser gyroscope can also be used. A third sensor is the combination of an integrating accelerometer and a laser gyroscope. The video data processing unit can incorporate the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion. [0000] Physician's Local Control Unit [0152] Another aspect includes a retinal prosthesis with (see FIG. 1 b ) a physician's local external control unit ( 115 ) allowing the physician to exert setup control of parameters such as amplitudes, pulse widths, frequencies, and patterns of electrical stimulation. The physician's control unit ( 115 ) is also capable of monitoring information from the implanted unit ( 121 ) such as electrode current, electrode impedance, compliance voltage, and electrical recordings from the retina. The monitoring is done via the internal telemetry unit, electrode and electronics assembly ( 121 ). [0153] An important aspect of setting up the retinal color prosthesis is setting up electrode current amplitudes, pulse widths, and frequencies so they are comfortable for the patient. FIGS. 17 a - c and FIGS. 18 a - c illustrate some of the typical displays. A computer-controlled stimulating test that incorporates patient response to arrive at optimal patient settings may be compared to being fitted for eyeglasses, first determining diopter, then cylindrical astigmatic correction, and so forth for each patient. The computer uses interpolation and extrapolation routines. Curve or surface or volume fitting of data may be used. For each pixel, the intensity in increased until a threshold is reached and the patient can detect something in his visual field. The intensity is further increased until the maximum comfortable brightness is reached. The patient determines his subjective impression of one-quarter maximum brightness, one-half maximum brightness, and three-quarters maximum brightness. Using the semi-automated processing of the patient-in-the-loop with the computer, the test program runs through the sequences and permutations of parameters and remembers the patient responses. In this way apparent brightness response curves are calibrated for each electrode for amplitude. Additionally, in the same way as for amplitude, pulse width and pulse rate (frequency), response curves are calibrated for each patient. The clinician can then determine what the best settings are for the patient. [0154] This method is generally applicable to many, if not all, types of electrode based retinal prostheses. Moreover, it also is applicable to the type of retinal prosthesis, which uses an external light intensifier shining upon essentially a spatially distributed set of light sensitive diodes with a light activated electrode. In this latter case, a physician's test, setup and control unit is applied to the light intensifier which scans the implanted photodiode array, element by element, where the patient can give feedback and so adjust the light intensifier parameters. [0000] Remote Physician's Unit [0155] Another aspect of an embodiment of this invention includes (see FIG. 1 b ) a remote physician control unit ( 117 ) that can communicate with a patient's unit ( 114 ) over the public switched telephone network or other telephony means. This telephone-based pair of units is capable of performing all of the functions of the of the physician's local control unit ( 115 ). [0000] Physician's Unit Measurements Menus and Displays [0156] Both the physician's local ( 115 ) and the physician's remote ( 117 ) units always measure brightness, amplitudes, pulse widths, frequencies, patterns of stimulation, shape of log amplification curve, electrode current, electrode impedance, compliance voltage and electrical recordings from the retina. [0157] FIG. 17 a shows the main screen of the Physician's Local and Remote Controller and Programmer. FIG. 17 b illustrates the pixel selection of the processing algorithm with the averaging of eight surrounding pixels chosen as one element of the processing. FIG. 17 c represents an electrode scanning sequence, in this case the predefined sequence, A. FIG. 17 d shows electrode parameters, here for electrode B, including current amplitudes and waveform timelines. FIG. 17 e illustrates the screen for choosing the global electrode configuration, monopolar, bipolar, or multipolar. FIG. 17 f renders a screen showing the definition of bipolar pairs (of electrodes). FIG. 17 g shows the definition of the multipole arrangements. [0158] FIG. 18 a illustrates the main menu screen for the palm-sized test unit. FIG. 18 b shows a result of pressing on the stimulate bar of the (palm-sized unit) main menu screen, where upon pressing the start button the amplitudes A 1 and A 2 are stimulated for times t 1 , t 2 , t 3 , and t 4 , until the stop button is pressed. FIG. 18 c exhibits a recording screen that shows the retinal recording of the post-stimulus and the electrode impedance. [0159] FIGS. 19 a , 19 b , and 19 c show different embodiments of the Physician's Remote Controller, which has the same functionality inside as the Physician's Local Controller but with the addition of communication means such as telemetry or telephone modem. [0000] Patient's Controller [0160] Corresponding to the Physician's Local Controller, but with much less capability, is the Patient's Controller. FIG. 20 shows the patient's local controller unit. This unit can monitor and adjust brightness ( 2001 ), contrast ( 2002 ) and magnification ( 2003 ) of the image on a non-continuous basis. The magnification control ( 2003 ) adjusts magnification both by optical zoom lens control of the lens for the imaging means ( FIG. 1, 111 ), and by electronic adjustment of the image in the data processor ( FIG. 2, 113 ). [0161] While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.
The present invention is an implantable electronic device formed within a biocompatible hermetic package. Preferably the implantable electronic device is used for a visual prosthesis for the restoration of sight in patients with lost or degraded visual function. The package may include a hard hermetic box, a thin film hermetic coating, or both.
Provide a concise summary of the essential information conveyed in the context.
[ "CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a Divisional Application of U.S. patent application Ser.", "No. 11/206,484, filed Aug. 17, 2005, which is a Divisional Application of U.S. patent application Ser.", "No. 09/515,373, filed Feb. 29, 2000, which claims the benefit of U.S. Provisional Application No. 60/125,873, filed Mar. 24, 1999.", "TECHNICAL FIELD OF INVENTION [0002] The present invention relates to electrical stimulation of the retina to produce artificial images for the brain.", "It relates to electronic image stabilization techniques based on tracking the movements of the eye.", "It relates to telemetry in and out of the eye for uses such as remote diagnostics and recording from the retinal surface.", "[0003] The present invention also relates to electrical stimulation of the retina to produce phosphenes and to produce induced color vision.", "The present invention relates to hermetically sealed electronic and electrode units which are safe to implant in the eye.", "BACKGROUND [0004] Color perception is part of the fabric of human experience.", "Homer (c.", "1100 b. c.) writes of “the rosy-fingered dawn.”", "Lady Murasaki no Shikibu (c.", "1000 a.d.) uses word colors (“purple, yellow shimmer of dresses, blue paper”) in the world's first novel.", "In the early nineteenth century Thomas Young, an English physician, proposed a trichromatic theory of color vision, based on the action of three different retinal receptors.", "Fifty years later James Clerk Maxwell, the British physicist and Hermann von Helmholtz, the German physiologist, independently showed that all of the colors we see can be made up from three suitable spectral color lights.", "In 1964 Edward MacNichol and colleagues at Johns Hopkins and George Wald at Harvard measured the absorption by the visual pigments in cones, which are the color receptor cells.", "Rods are another type of photoreceptor cell in the primate retina.", "These cells are more sensitive to dimmer light but are not directly involved in color perception.", "The individual cones have one of three types of visual pigment.", "The first is most sensitive to short waves, like blue.", "The second pigment is most sensitive to middle wavelengths, like green.", "The third pigment is most sensitive to longer wavelengths, like red.", "[0005] The retina can be thought of a big flower on a stalk where the top of that stalk is bent over so that the back of the flower faces the sun.", "In place of the sun think of the external light focused by the lens of the eye onto the back of the flower.", "The cones and rods cells are on the front of the flower;", "they get the light which has passed through from the back of the somewhat transparent flower.", "The photoreceptor nerve cells are connected by synapses to bipolar nerve cells, which are then connected to the ganglion nerve cells.", "The ganglion nerve cells connect to the optic nerve fibers, which is the “stalk”", "that carries the information generated in the retina to the brain.", "Another type of retinal nerve cell, the horizontal cell, facilitates the transfer of information horizontally across bipolar cells.", "Similarly, another type of cell, the amacrine facilitates the horizontal transfer of information across the ganglion cells.", "The interactions among the retinal cells can be quite complex.", "On-center and off-center bipolar cells can be stimulated at the same time by the same cone transmitter release to depolarize and hyperpolarize, respectively.", "A particular cell's receptive field is that part of the retina, which when stimulated, will result in that cell's stimulation.", "Thus, most ganglion cells would have a larger receptive field than most bipolar cells.", "Where the response to the direct light on the center of a ganglion cells receptive field is antagonized by direct light on the surround of its receptive field, the effect is called center-surround antagonism.", "This phenomenon is important for detecting borders independent of the level of illumination.", "The existence of this mechanism for sharpening contrast was first suggested by the physicist Ernst Mach in the late 1800's.", "More detailed theories of color vision incorporate color opponent cells.", "On the cone level, trichromatic activity of the cone cells occurs.", "At the bipolar cell level, green-red opponent and blue-yellow opponent processing systems of the center-surround type, occur.", "For example, a cell with a green responding center would have a annular surround area, which responded in an inhibiting way to red.", "Similarly there can be red-center responding, green-surround inhibiting response.", "The other combinations involve blue and yellow in an analogous manner.", "[0006] It is widely known that Galvani, around 1780, stimulated nerve and muscle response electrically by applying a voltage on a dead frog's nerve.", "Less well known is that in 1755 LeRoy discharged a Leyden jar, i.e., a capacitor, through the eye of a man who had been blinded by the growth of a cataract.", "The patient saw “flames passing rapidly downward.”", "[0007] In 1958, Tassicker was issued a patent for a retinal prosthetic utilizing photosensitive material to be implanted subretinally.", "In the case of damage to retinal photoreceptor cells that affected vision, the idea was to electrically stimulate undamaged retinal cells.", "The photosensitive material would convert the incoming light into an electrical current, which would stimulate nearby undamaged cells.", "This would result in some kind of replacement of the vision lost.", "Tassicker reports an actual trial of his device in a human eye.", "(U.S. Pat. No. 2,760,483).", "[0008] Subsequently, Michelson (U.S. Pat. No. 4,628,933), Chow (U.S. Pat. Nos. 5,016,633;", "5,397,350;", "5,556,423), and De Juan (U.S. Pat. No. 5,109,844) all were issued patents relating to a device for stimulating undamaged retinal cells.", "Chow and Michelson made use of photodiodes and electrodes.", "The photodiode was excited by incoming photons and produced a current at the electrode.", "[0009] Normann et al.", "(U.S. Pat. No. 5,215,088) discloses long electrodes 1000 to 1500 microns long designed to be implanted into the brain cortex.", "These spire-shaped electrodes were formed of a semiconductor material.", "[0010] Najafi, et al.", ", (U.S. Pat. No. 5,314,458), disclosed an implantable silicon-substrate based microstimulator with an external device which could send power and signal to the implanted unit by RF means.", "The incoming RF signal could be decoded and the incoming RF power could be rectified and used to run the electronics.", "[0011] Difficulties can arise if the photoreceptors, the electronics, and the electrodes all tend to be mounted at one place.", "One issue is the availability of sufficient area to accommodate all of the devices, and another issue is the amount of power dissipation near the sensitive retinal cells.", "Since these devices are designed to be implanted into the eye, this potential overheating effect is a serious consideration.", "[0012] Since these devices are implants in the eye, a serious problem is how to hermetically seal these implanted units.", "Of further concern is the optimal shape for the electrodes and for the insulators, which surround them.", "In one embodiment there is a definite need that the retinal device and its electrodes conform to the shape of the retinal curvature and at the same time do not damage the retinal cells or membranes.", "[0013] The length and structure of electrodes must be suitable for application to the retina, which averages about 200 microns in thickness.", "Based on this average retinal thickness of 200 microns, elongated electrodes in the range of 100 to 500 microns appear to be suitable.", "These elongated electrodes reach toward the cells to be activated.", "Being closer to the targeted cell, they require less current to activate it.", "[0014] In order not to damage the eye tissue there is a need to maintain an average charge neutrality and to avoid introducing toxic or damaging effects from the prosthesis.", "[0015] A desirable property of a retinal prosthetic system is making it possible for a physician to make adjustments on an on-going basis from outside the eye.", "One way of doing this would have a physician's control unit, which would enable the physician to make adjustments and monitor the eye condition.", "An additional advantageous feature would enable the physician to perform these functions at a remote location, e.g., from his office.", "This would allow one physician to remotely monitor a number of patients remotely without the necessity of the patient coming to the office.", "A patient could be traveling distantly and obtain physician monitoring and control of the retinal color prosthetic parameters.", "[0016] Another version of the physician's control unit is a hand-held, palm-size unit.", "This unit will have some, but not all of the functionality of the physician's control unit.", "It is for the physician to carry on his rounds at the hospital, for example, to check on post-operative retinal-prosthesis implant patients.", "Its extreme portability makes other situational uses possible, too, as a practical matter.", "[0017] The patient will want to control certain aspects of the visual image from the retinal prosthesis system, in particular, image brightness.", "Consequently, a patient controller, performing fewer functions than the physician's controller is included as part of the retinal prosthetic system.", "It will control, at a minimum, bright image, and it will control this image brightness in a continuous fashion.", "The image brightness may be increased or decreased by the patient at any time, under normal circumstances.", "[0018] A system of these components would itself constitute part of a visual prosthetic to form images in real time within the eye of a person with a damaged retina.", "In the process of giving back sight to those who are unable to see, it would be advantageous to supply artificial colors in this process of reconstructing sight so that the patient would be able to enjoy a much fuller version of the visual world.", "[0019] In dealing with externally mounted or externally placed means for capturing image and transmitting it by electronic means or other into the eye, one must deal with the problem of stabilization of the image.", "For example, a head-mounted camera would not follow the eye movement.", "It is desirable to track the eye movements relative to the head and use this as a method or approach to solving the image stabilization problem.", "[0020] By having a method and apparatus for the physician and the technician to initially set up and measure the internal activities and adjust these, the patient's needs can be better accommodated.", "The opportunity exists to measure internal activity and to allow the physician, using his judgment, to adjust settings and controls on the electrodes.", "Even the individual electrodes would be adjusted by way of the electronics controlling them.", "By having this done remotely, by remote means either by telephone or by the Internet or other such, it is clear that a physician would have the capability to intervene and make adjustment as necessary in a convenient and inexpensive fashion, to serve many patients.", "SUMMARY OF INVENTION [0021] The objective of the current invention is to restore color vision, in whole or in part, by electrically stimulating undamaged retinal cells, which remain in patients with lost or degraded visual function arising, for example, from Retinitis Pigmentosa or Age-Related Macular Degeneration.", "This invention is directed toward patients who have been blinded by degeneration of photoreceptors;", "but who have sufficient bipolar cells, or other cells acting similarly, to permit electrical stimulation.", "[0022] There are three main functional parts to this invention.", "One is external to the eye.", "The second part is internal to the eye.", "The third part is the communication circuitry for communicating between those two parts.", "Structurally there are two parts.", "One part is external to the eye and the other part in implanted within the eye.", "Each of these structural parts contains two way communication circuitry for communication between the internal and external parts.", "[0023] The structural external part is composed of a number of subsystems.", "These subsystems include an external imager, an eye-motion compensation system, a head motion compensation system, a video data processing unit, a patient's controller, a physician's local controller, a physician's remote controller, and a telemetry unit.", "The imager is a video camera such as a CCD or CMOS video camera.", "It gathers an image approximating what the eyes would be seeing if they were functional.", "[0024] The imager sends an image in the form of electrical signals to the video data processing unit.", "In one aspect, this unit formats a grid-like or pixel-like pattern that is then ultimately sent to electronic circuitry (part of the internal part) within the eye, which drives the electrodes.", "These electrodes are inside the eye.", "They replicate the incoming pattern in a useable form for stimulation of the retina so as to reproduce a facsimile of the external scene.", "In an other aspect of this invention other formats other than a grid-like or pixel like pattern are used, for example a line by line scan in some order, or a random but known order, point-by-point scan.", "Almost any one-to-one mapping between the acquired image and the electrode array is suitable, as long as the brain interprets the image correctly.", "[0025] The imager acquires color information.", "The color data is processed in the video data processing unit.", "The video data processing unit consists of microprocessor CPU's and associated processing chips including high-speed data signal processing (DSP) chips.", "[0026] In one aspect, the color information is encoded by time sequences of pulses separated by varying amounts of time;", "and, the pulse duration may be different for various pulses.", "The basis for the color encoding is the individual color code reference ( FIG. 2 a ).", "The electrodes stimulate the target cells so as to create a color image for the patient, corresponding to the original image as seen by the video camera, or other imaging means.", "[0027] Color information, in an alternative aspect, is sent from the video data processing unit to the electrode array, where each electrode has been determined to stimulate preferentially one of the bipolar cell types, namely, red-center green-surround, green-center-red-surround, blue-center-yellow-surround, or yellow-center-blue-surround.", "[0028] An eye-motion compensation system is an aspect of this invention.", "The eye tracker is based on detection of eye motion from the corneal reflex or from implanted coils of wire, or, more generally, insulated conductive coils, on the eye or from the measurement of electrical activity of extra-ocular muscles.", "Communication is provided between the eye tracker and the video data processing unit by electromagnetic or acoustical telemetry.", "In one embodiment of the invention, electromagnetic-based telemetry may be used.", "The results of detecting the eye movement are transmitted to a video data processing unit, together with the information from the camera means.", "Another aspect of the invention utilizes a head motion sensor and head motion compensation system.", "The video data processing unit can incorporate the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion.", "[0029] The internal structural part which is implanted internally within the eye, is also composed of a number of subsystems.", "These can be categorized as electronic circuits and electrode arrays, and communication subsystems, which may include electronic circuits.", "The circuits, the communication subsystems, and the arrays can be hermetically sealed and they can be attached one to the other by insulated wires.", "The electrode arrays and the electronic circuits can be on one substrate, or they may be on separate substrates joined by an insulated wire or by a plurality of insulated wires.", "This is similarly the case for a communication subsystem.", "[0030] A plurality of predominately electronic substrate units and a plurality of predominately electrode units may be implanted or located within the eye as desired or as necessary.", "The electrodes are designed so that they and the electrode insulation conform to the retinal curvature.", "The variety of electrode arrays include recessed electrodes so that the electrode array surface coming in contact with the retinal membrane or with the retinal cells is the non-metallic, more inert insulator.", "[0031] Another aspect of the invention is the elongated electrode, which is designed to stimulate deeper retinal cells by penetrating into the retina by virtue of the length of its electrodes.", "A plurality of electrodes is used.", "The elongated electrodes are of lengths from 100 microns to 500 microns.", "With these lengths, the electrode tips can reach through those retinal cells not of interest but closer to the target stimulation cells, the bipolar cells.", "The number of electrodes may range from 100 on up to 10,000 or more.", "With the development of electrode fabrication technology, the number of electrodes might rage up to one million or more.", "[0032] Another aspect of the invention uses a plurality of capacitive electrodes to stimulate the retina, in place of non-capacitive electrodes.", "Another aspect of the invention is the use of a neurotrophic factor, for example, Nerve Growth Factor, applied to the electrodes, or to the vicinity of the electrodes, to aid in attracting target nerves and other nerves to grow toward the electrodes.", "[0033] Hermetic sealing is accomplished by coating the object to be sealed with a substance selected from the group consisting of silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide, zirconium oxide.", "This hermetic sealing aspect of the invention provides an advantageous alternative to glass coverings for hermetic seals, being less likely to become damaged.", "[0034] Another feature of one aspect of the structural internal-to-the-eye subsystems is that the electronics receive and transmit information in coded or pulse form via electromagnetic waves.", "In the case where electromagnetic waves are used, the internal-to-the-eye implanted electronics can rectify the RF, or electromagnetic wave, current and decode it.", "The power being sent in through the receiving coil is extracted and used to drive the electronics.", "In some instances, the implanted electronics acquire data from the electrode units to transmit out to the video data processing unit.", "[0035] In another aspect the information coding is done with ultrasonic sound.", "An ultrasonic transducer replaces the electromagnetic wave receiving coil inside the eye.", "An ultrasonic transducer replaces the coil outside the eye for the ultrasonic case.", "By piezoelectric effects, the sound vibration is turned into electrical current, and energy extracted therefrom.", "[0036] In another aspect of the invention, information is encoded by modulating light.", "For the light modulation case, a light emitting diode (LED) or laser diode or other light generator, capable of being modulated, acts as the information transmitter.", "Information is transferred serially by modulating the light beam, and energy is extracted from the light signal after it is converted to electricity.", "A photo-detector, such as a photodiode, which turns the modulated light signal into a modulated electrical signal, is used as a receiver.", "[0037] Another aspect of the structural internal-to-the-eye subsystems of this invention is that the predominately electrode array substrate unit and the predominately electronic substrate unit, which are joined by insulated wires, can be placed near each other or in different positions.", "For example, the electrode array substrate unit can be placed subretinally and the electronic substrate unit placed epiretinally.", "On a further aspect of this invention, the electronic substrate unit can be placed distant from the retina so as to avoid generating additional heat or decreasing the amount of heat generated near the retinal nerve system.", "For example, the receiving and processing circuitry could be placed in the vicinity of the pars plana.", "In the case where the electronics and the electrodes are on the same substrate chip, two of these chips can be placed with the retina between them, one chip subretinal and the other chip epiretinal, such that the electrodes on each may be aligned.", "Two or more guide pins with corresponding guide hole or holes on the mating chip accomplish the alignment.", "Alternatively, two or more tiny magnets on each chip, each magnet of the correct corresponding polarity, may similarly align the sub- and epiretinal electrode bearing chips.", "Alternatively, corresponding parts which mate together on the two different chips and which in a fully mated position hold each other in a locked or “snap-together”", "relative position.", "[0038] Now as an element of the external-to-the-eye structural part of the invention, there is a provision for a physician's hand-held test unit and a physician's local or remote office unit or both for control of parameters such as amplitudes, pulse widths, frequencies, and patterns of electrical stimulation.", "[0039] The physician's hand-held test unit can be used to set up or evaluate and test the implant during or soon after implantation at the patient's bedside.", "It has, essentially, the capability of receiving what signals come out of the eye and having the ability to send information in to the retinal implant electronic chip.", "For example, it can adjust the amplitudes on each electrode, one at a time, or in groups.", "The hand-held unit is primarily used to initially set up and make a determination of the success of the retinal prosthesis.", "[0040] The physician's local office unit, which may act as a set-up unit as well as a test unit, acts directly through the video data processing unit.", "The remote physician's office unit would act over the telephone lines directly or through the Internet or a local or wide area network.", "The office units, local and remote, are essentially the same, with the exception that the physician's remote office unit has the additional communications capability to operate from a location remote from the patient.", "It may evaluate data being sent out by the internal unit of the eye, and it may send in information.", "Adjustments to the retinal color prosthesis may be done remotely so that a physician could handle a multiple number of units without leaving his office.", "Consequently this approach minimizes the costs of initial and subsequent adjustments.", "BRIEF DESCRIPTION OF THE DRAWINGS [0041] The above and other features and advantages of the invention will be more apparent from the following detailed description wherein: [0042] FIG. 1 a shows the general structural aspects of the retina color prosthesis system;", "[0043] FIG. 1 b shows the retina color prosthesis system with a structural part internal (to the eye), with an external part with subsystems for eye-motion feedback to enable maintaining a stable image presentation, and with a subsystems for communicating between the internal and external parts, and other structural subsystems;", "[0044] FIG. 1 c shows an embodiment of the retina color prosthesis system which is, in part, worn in eyeglass fashion;", "[0045] FIG. 1 d shows the system in FIG. 1 c in side view;", "[0046] FIG. 2 a shows an embodiment of the color I coding schemata for the stimulation of the sensation of color;", "[0047] FIG. 2 b represents an embodiment of the color I conveying method where a “large”", "electrode stimulates many bipolar cells with the color coding schemata of FIG. 2 a;", "[0048] FIG. 2 c represents an embodiment of the color II conveying method where an individual electrode stimulates a single type of bipolar cell;", "[0049] FIG. 3 a represents an embodiment of the telemetry unit including an external coil, an internal (to the eye) coil, and an internal electronic chip;", "[0050] FIG. 3 b represents an embodiment of the telemetry unit including an external coil, an internal (to the eye) coil, an external electronic chip, a dual coil transfer unit, and an internal electrode array;", "[0051] FIG. 3 c shows and acoustic energy and information transfer system;", "[0052] FIG. 3 d shows a light energy and information transfer system;", "[0053] FIG. 4 represents an embodiment of the external telemetry unit;", "[0054] FIG. 5 shows an embodiment of an internal telemetry circuit and electrode array switcher;", "[0055] FIG. 6 a shows a monopolar electrode arrangement and illustrates a set of round electrodes on a substrate material;", "[0056] FIG. 6 b shows a bipolar electrode arrangement;", "[0057] FIG. 6 c shows a multipolar electrode arrangement;", "[0058] FIG. 7 shows the corresponding indifferent electrode for monopolar electrodes;", "[0059] FIG. 8 a depicts the location of an epiretinal electrode array located inside the eye in the vitreous humor located above the retina, toward the lens capsule and the aqueous humor;", "[0060] FIG. 8 b shows recessed epiretinal electrodes where the electrically conducting electrodes are contained within the electrical insulation material;", "a silicon chip acts as a substrate;", "and the electrode insulator device is shaped so as to contact the retina in a conformal manner;", "[0061] FIG. 8 c is a rendering of an elongated epiretinal electrode array with the electrodes shown as pointed electrical conductors, embedded in an electrical insulator, where an pointed electrodes contact the retina in a conformal manner, however, elongated into the retina;", "[0062] FIG. 9 a shows the location of a subretinal electrode array below the retina, away from the lens capsule and the aqueous humor.", "The retina separates the subretinal electrode array from the vitreous humor;", "[0063] FIG. 9 b illustrates the subretinal electrode array with pointed elongated electrode, the insulator, and the silicon chip substrate where the subretinal electrode array is in conformal contact with the retina with the electrodes elongated to some depth;", "[0064] FIG. 10 a shows a iridium electrode that comprises a iridium slug, an insulator, and a device substrate where this embodiment shows the iridium slug electrode flush with the extent of the insulator;", "[0065] FIG. 10 b indicates an embodiment similar to that shown in FIG. 10 / 12 a , however, the iridium slug is recessed from the insulator along its sides, but with its top flush with the insulator;", "[0066] FIG. 10 c shows an embodiment with the iridium slug as in FIG. 10 / 12 b ;", "however, the top of the iridium slug is recessed below the level of the insulator;", "[0067] FIG. 10 d indicates an embodiment with the iridium slug coming to a point and insulation along its sides, as well as a being within the overall insulation structure;", "[0068] FIG. 10 e indicates an embodiment of a method for fabricating and the fabricated iridium electrode where on a substrate of silicon an aluminum pad is deposited;", "on the pad the conductive adhesive is laid and platinum or iridium foil is attached thereby;", "a titanium ring is placed, sputtered, plated, ion implanted, ion beam assisted deposited (IBAD) or otherwise attached to the platinum or iridium foil;", "silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide or other insulator will adhere better to the titanium while it would not adhere as well to the platinum or iridium foil;", "[0069] FIG. 11 a depicts a preferred electrode where it is formed on a silicon substrate and makes use of an aluminum pad, a metal foil such as platinum or iridium, conductive adhesive, a titanium ring, aluminum or zirconium oxide, an aluminum layer, and a mask;", "[0070] FIG. 11 b shows an elongated electrode formed on the structure of FIG. 11 a with platinum electroplated onto the metal foil, the mask removed and insulation applied over the platinum electrode;", "[0071] FIG. 11 c shows a variation of a form of the elongated electrode wherein the electrode is thinner and more recessed from the well sides;", "[0072] FIG. 11 d shows a variation of a form of the elongated electrode wherein the electrode is squatter but recessed from the well sides;", "[0073] FIG. 11 e shows a variation of a form of the elongated electrode wherein the electrode is a mushroom shape with the sides of its tower recessed from the well sides and its mushroom top above the oxide insulating material;", "[0074] FIG. 12 a shows the coil attachment to two different conducting pads at an electrode node;", "[0075] FIG. 12 b shows the coil attachment to two different conducting pads at an electrode node, together with two separate insulated conducting electrical pathways such as wires, each attached at two different electrode node sites on two different substrates;", "[0076] FIG. 12 c shows an arrangement similar to that seen in FIG. 12 / 16 d , with the difference that the different substrates are very close with a non-conducting adhesive between them and an insulator such as aluminum or zirconium oxide forms a connection coating over the two substrates, in part;", "[0077] FIG. 12 d depicts an arrangement similar to that seen in FIG. 12 / 16 c ;", "however, the connecting wires are replaced by an externally placed aluminum conductive trace;", "[0078] FIG. 13 shows a hermetically sealed flip-chip in a ceramic or glass case with solder ball connections to hermetically sealed glass frit and metal leads;", "[0079] FIG. 14 shows a hermetically sealed electronic chip as in FIG. 18 with the addition of biocompatible leads to pads on a remotely located electrode substrate;", "[0080] FIG. 15 shows discrete capacitors on the electrode-opposite side of an electrode substrate;", "[0081] FIG. 16 a shows an electrode-electronics retinal implant placed with the electrode half implanted beneath the retina, subretinally, while the electronics half projects above the retina, epiretinally;", "[0082] FIG. 16 b shows another form of sub- and epi-retinal implantation wherein half of the electrode implant is epiretinal and half is subretinal;", "[0083] FIG. 16 c shows the electrode parts are lined up by alignment pins or by very small magnets;", "[0084] FIG. 16 d shows the electrode part lined up by template shapes which may snap together to hold the parts in a fixed relationship to each other;", "[0085] FIG. 17 a shows the main screen of the physician's (local) controller (and programmer);", "[0086] FIG. 17 b illustrates the pixel selection of the processing algorithm with the averaging of eight surrounding pixels chosen as one element of the processing;", "[0087] FIG. 17 c represents an electrode scanning sequence, in this case the predefined sequence, A;", "[0088] FIG. 17 d shows electrode parameters, here for electrode B, including current amplitudes and waveform timelines;", "[0089] FIG. 17 e illustrates the screen for choosing the global electrode configuration, monopolar, bipolar, or multipolar;", "[0090] FIG. 17 f renders a screen showing the definition of bipolar pairs (of electrodes);", "[0091] FIG. 17 g shows the definition of the multipole arrangements;", "[0092] FIG. 18 a illustrates the main menu screen for the palm-sized test unit;", "[0093] FIG. 18 b shows a result of pressing on the stimulate bar of the main menu screen, where upon pressing the start button the amplitudes A 1 and A 2 are stimulated for times t 1 , t 2 , t 3 , and t 4 , until the stop button is pressed;", "[0094] FIG. 18 c exhibits a recording screen that shows the retinal recording of the post-stimulus and the electrode impedance;", "[0095] FIG. 19 a - c show the physician's remote controller that has the same functionality inside as the physician's controller but with the addition of communication means such as telemetry or telephone modem;", "and [0096] FIG. 20 shows the patient's controller unit.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS [0097] The following description is of the best mode presently contemplated for carrying out the invention.", "This description is not to be taken in a limiting sense, but is merely made for the purpose of describing the general principles of the invention.", "The scope of the invention should be determined with reference to the claims.", "[0000] Objective [0098] The objective of the embodiments of the current invention is a retinal color prosthesis to restore color vision, in whole or in part, by electrically stimulating undamaged retinal cells, which remain in patients with, lost or degraded visual function.", "Embodiments of this retinal color prosthesis invention are directed toward helping patients who have been blinded by degeneration of photoreceptors and other cells;", "but who have sufficient bipolar cells and the like to permit the perception of color vision by electric stimulation.", "By color vision, it is meant to include black, gray, and white among the term color.", "[0000] General Description [0099] Functionally, there are three main parts to an embodiment of this retinal color prosthesis invention.", "See FIG. 1 a .", "FIG. 1 a is oriented toward showing the main structural parts and subsystems, with a dotted enclosure to indicate a functional intercommunications aspect.", "The first part of the embodiment is external ( 1 ) to the eye.", "The second part is implanted internal ( 2 ) to the eye.", "The third part is means for communication between those two parts ( 3 ).", "Structurally there are two parts.", "One part is external ( 1 ) to the eye and the other part ( 2 ) is implanted within the eye.", "Each of these structural parts contains two way communication circuitry for communication ( 3 ) between the internal ( 2 ) and external ( 1 ) parts.", "[0100] The external part of the retinal color prosthesis is carried by the patient.", "Typically, the external part including imager, video data processing unit, eye-tracker, and transmitter/receiver are worn as an eyeglass-like unit.", "Typical of this embodiment, a front view of one aspect of the structural external part ( 1 ) of the color retinal prosthesis is shown in FIG. 1 c and a side view is shown in FIG. 1 d , ( 1 ).", "In addition, there are two other units which may be plugged into the external unit;", "when this is done they act as part of the external unit.", "The physician's control unit is not normally plugged into the external part worn by the patient, except when the physician is conducting an examination and adjustment of the retinal color prosthetic.", "The patient's controller may or may not be normally plugged in.", "When the patient's controller is plugged in, it can also receive signals from a remote physician's controller which then acts in the same way as the plug-in physician's controller.", "[0101] Examining further the embodiment of the subsystems of the external part, see FIG. 1 b .", "These include an external color imager ( 111 ), an eye-motion compensation system ( 112 ), a head-motion compensation system ( 131 ), a processing unit ( 113 ), a patient's controller ( 114 ), a physician's local controller ( 115 ), a physicians hand-held palm-size pocket-size unit ( 130 ), a physician's remote controller ( 117 ), and a telemetry means ( 118 ).", "The color imager is a color video camera such as a CCD or CMOS video camera.", "It gathers an image approximating what the eyes would be seeing if they were functional.", "[0102] An external imager ( 111 ) sends an image in the form of electrical signals to the video data processing unit ( 113 ).", "The video data processing unit consists of microprocessor CPU's and associated processing chips including high-speed data signal processing (DSP) chips.", "This unit can format a grid-like or pixel-like pattern that is sent to the electrodes by way of the telemetry communication subsystems ( 118 , 121 ).", "See FIG. 1 b .", "In this embodiment of the retinal color prosthesis ( FIG. 1 b , ( 121 )), these electrodes are incorporated in the internal-to-the eye implanted part.", "[0103] These electrodes, which are part of the internal implant ( 121 ), together with the telemetry circuitry ( 121 ) are inside the eye.", "With other internally implanted electronic circuitry ( 121 ), they cooperate with the electrodes so as to replicate the incoming pattern, in a useable form, for stimulation of the retina so as to reproduce a facsimile perception of the external scene.", "The eye-motion ( 112 ) and head-motion ( 131 ) detectors supply information to the video data processing unit ( 113 ) to shift the image presented to the retina ( 120 ).", "[0104] There are three preferred embodiments for stimulating the retina via the electrodes to convey the perception of color.", "Color information is acquired by the imaging means ( 111 ).", "The color data is processed in the video data processing unit ( 113 ).", "[0000] First Preferred Color Mode [0105] Color information (See FIG. 2 a ), in the first preferred embodiment, is encoded by time sequences of pulses ( 201 ) separated by varying amounts of time ( 202 ), and also with the pulse duration being varied in time ( 203 ).", "The basis for the color encoding is the individual color code reference ( 211 through 217 ).", "The electrodes stimulate the target cells so as to create a color image for the patient, corresponding to the original image as seen by the video camera, or other imaging means.", "Using temporal coding of electrical stimuli placed (cf.", "FIG. 2 b , 220 , FIG. 2 c , 230 ) on or near the retina ( FIG. 2 b and FIG. 2 c , 221 , 222 ) the perception of color can be created in patients blinded by outer retinal degeneration.", "By sending different temporal coding schemes to different electrodes, an image composed of more than one color can be produced.", "FIG. 2 shows one stimulation protocol.", "Cathodic stimuli ( 202 ) are below the zero plane ( 220 ) and anodic stimuli ( 203 ) are above.", "All the stimulus rates are either “fast”", "( 203 ) or “slow”", "( 202 ) except for green ( 214 ), which includes an intermediate stimulus rate ( 204 ).", "The temporal codes for the other colors are shown as Red ( 211 ), as Magenta ( 212 ), as Cyan ( 213 ), as Yellow ( 215 ), as Blue ( 216 ), as Neutral ( 217 ).", "This preferred embodiment is directed toward electrodes which are less densely packed in proximity to the retinal cells.", "[0000] Second Preferred Color Mode [0106] Color information, in a second preferred embodiment, is sent from the video data processing unit to the electrode array, where each electrode has been determined by test to stimulate one of a bipolar type: red-center green-surround, green-center-red-surround, blue-center-yellow-surround, or yellow-center-blue-surround.", "In this embodiment, electrodes which are small enough to interact with a single cell, or at most, a few cells are placed in the vicinity of individual bipolar cells, which react to a stimulus with nerve pulse rates and nerve pulse structure (i.e., pulse duration and pulse amplitude).", "Some of the bipolar cells, when electrically, or otherwise, stimulated, will send red-green signals to the brain.", "Others will send yellow-blue signals.", "This refers to the operation of the normal retina.", "In the normal retina, red or green color photoreceptors (cone cells) send nerve pulses to the red-green bipolar cell which then pass some form of this information up to the ganglion cells and then up to the visual cortex of the brain.", "With small electrodes individual bipolar cells can be excited in a spatial, or planar, pattern.", "Small electrodes are those with tip from 0.1 μm to 15 μm, and which individual electrodes are spaced apart from a range 8 μm to 24 μm, so as to approximate a one-to-one correspondence with the bipolar cells.", "The second preferred embodiment is oriented toward a more densely packed set of electrodes.", "[0000] Third Preferred Color Mode [0107] A third preferred mode is a combination of the first and of the second preferred modes such that a broader area coverage of the color information encoded by time sequences of pulses, of varying widths and separations and with relatively fewer electrodes is combined with a higher density of electrodes, addressing more the individual bipolar cells.", "[0000] First Order and Higher Effects [0108] Regardless of a particular theory of color vision, the impinging of colored light on the normal cones, and possibly rods, give rise in some fashion to the perception of color, i.e., multi-spectral vision.", "In the time-pulse coding color method, above, the absence of all, or sufficient, numbers of working cones (and rods) suggests a generalization of the particular time-pulse color encoding method.", "The generalization is based on the known, or partly known, neuron conduction pathways in the retina.", "The cone cells, for example, signal to bipolar cells, which in turn signal the ganglion cells.", "The original spatial-temporal-color (including black, white) scheme for conveying color information as the cone is struck by particular wavelength photons is then transformed to a patterned signal firing of the next cellular level, say the bipolar cells, unless the cones are absent or don't function.", "Thus, this second level of patterned signal firing is what one wishes to supply to induce the perception of color vision.", "[0109] The secondary layer of patterned firing may be close to the necessary primary pattern, in which case the secondary pattern (S) may be represented as P*(1+ε).", "The * indicates matrix multiplication.", "P is the primary pattern, represented as a matrix P= [ p 11 p 1 ⁢ j p k ⁢ ⁢ 1 p kj ] where P represents the light signals of a particular spatial-temporal pattern, e.g., flicker signals for green.", "The output from the first cell layer, say the cones, is then S, the secondary pattern.", "This represents the output from the bipolar layer in response to the input from the first (cone) layer.", "If S=P*(1+ε), where 1 represents a vector and E represents a small deviation applied to the vector 1, then S is represented by P to the lowest order, and by P*(1+ε) to the next order.", "Thus, the response may be seen as a zero order effect and a first order linear effect.", "Additional terms in the functional relationship are included to completely define the functional relationship.", "If S is some non-linear function of P, finding S by starting with P requires more terms then the linear case to define the bulk of the functional relationship.", "However, regardless of the details of one color vision theory or another, on physiological grounds S is some function of P. As in the case of fitting individual patients with lenses for their glasses, variations of parameters are expected in fitting each patient to a particular temporal coding of electrical stimuli.", "Scaling Data from Photoreceptors to Bipolar Cells [0110] As cited above, Greenberg (1998), indicates that electrical and photic stimulation of the normal retina operate via similar mechanisms.", "Thus, even though electrical stimulation of a retina damaged by outer retinal degeneration is different from the electrical stimulation of a normal retina, the temporal relationships are expected to be analogous.", "[0111] To explain this, it is noted that electrical stimulation of the normal retinal is accomplished by stimulating the photoreceptor cells (including the color cells activated differentially according to the color of light impinging on them).", "For the outer retinal degeneration, it is precisely these photoreceptor cells which are missing.", "Therefore, the electrical stimulation in this case proceeds by way of the cells next up the ladder toward the optic nerve, namely, the bipolar cells.", "[0112] The time constant for stimulating photoreceptor is about 20 milliseconds.", "Thus the electrical pulse duration would need to be at least 20 milliseconds.", "The time constant for stimulating bipolar cells is around 9 seconds.", "These time constants are much longer than for the ganglion cells (about 1 millisecond).", "The ganglion cells are another layer of retinal cells closer to the optic nerve.", "The actual details of the behavior of the different cell types of the retina are quite complicated including the different relationships for current threshold versus stimulus duration (cf.", "Greenberg, 1998).", "One may, however, summarize an apparent resonant response of the cells based on their time constants corresponding to the actual pulse stimulus duration.", "[0113] In FIG. 2 , which is extrapolated from external-to-the-eye electrical stimulation data of Young (1977) and from light stimulation data of Festinger, Allyn, and White (1971), there is shown data that would be applicable to the photoreceptor cells.", "One may scale the data down based on the ratio of the photoreceptor time constant (about 20 milliseconds) to that of the bipolar cells (about 9 milliseconds).", "Consequently, 50 milliseconds on the time scale in FIG. 2 now corresponds to 25 milliseconds.", "Advantageously, stimulation rates and duration of pulses, as well as pulse widths may be chosen which apply to the electrode stimulation of the bipolar cells of the retina.", "[0000] Eye Movement/Head Motion Compensation [0114] In a preferred embodiment, an external imager such as a color CCD or color CMOS video camera ( 111 ) and a video data processing unit ( 113 ), with an external telemetry unit ( 118 ) present data to the internal eye-implant part.", "Another aspect of the preferred embodiment is a method and apparatus for tracking eye movement ( 112 ) and using that information to shift ( 113 ) the image presented to the retina.", "Another aspect of the preferred embodiment utilizes a head motion sensor ( 131 ) and a head motion compensation system ( 131 , 113 ).", "The video data processing unit incorporates the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion.", "Thus electronic image compensation, stabilization and adjustment are provided by the eye and head movement compensation subsystems of the external part of the retinal color prosthesis.", "[0000] Logarithmic Encoding of Light [0115] In one aspect of an embodiment ( FIG. 1 b ), light amplitude is recorded by the external imager ( 111 ).", "The video data processing unit uses a logarithmic encoding scheme ( 113 ) to convert the incoming light amplitudes into the logarithmic electrical signals of these amplitudes ( 113 ).", "These electrical signals are then passed on by telemetry ( 118 ), ( 121 ), to the internal implant ( 121 ) which results in the retinal cells ( 120 ) being stimulated via the implanted electrodes ( 121 ), in this embodiment as part of the internal implant ( 121 ).", "Encoding is done outside the eye, but may be done internal to the eye, with a sufficient internal computational capability.", "[0000] Energy and Signal Transmission [0000] Coils [0116] The retinal prosthesis system contains a color imager ( FIG. 1 b , 111 ) such as a color CCD or CMOS video camera.", "The imaging output data is typically processed ( 113 ) into a pixel-based format compatible with the resolution of the implanted system.", "This processed data ( 113 ) is then associated with corresponding electrodes and amplitude and pulse-width and frequency information is sent by telemetry ( 118 ) into the internal unit coils, ( 311 ), ( 313 ), ( 314 ) (see FIG. 3 a ).", "Electromagnetic energy, is transferred into and out from an electronic component ( 311 ) located internally in the eye ( 312 ), using two insulated coils, both located under the conjunctiva of the eye with one free end of one coil ( 313 ) joined to one free end of the second coil ( 314 ), the second free end of said one coil joined to the second free end of said second coil.", "The second coil ( 314 ) is located in proximity to a coil ( 311 ) which is a part of said internally located electronic component, or, directly to said internally located electronic component ( 311 ).", "The larger coil is positioned near the lens of the eye.", "The larger coil is fastened in place in its position near the lens of the eye, for example, by suturing.", "FIG. 3 b represents an embodiment of the telemetry unit temporally located near the eye, including an external temporal coil ( 321 ), an internal (to the eye) coil ( 314 ), an external-to-the-eye electronic chip ( 320 ), dual coil transfer units ( 314 , 323 ), ( 321 , 322 ) and an internal-to-the-eye electrode array ( 325 ).", "The advantage of locating the external electronics in the fatty tissue behind the eye is that there is a reasonable amount of space there for the electronics and in that position it appears not to interfere with the motion of the eye.", "[0000] Ultrasonic Sound [0117] In another aspect the information coding is done with ultrasonic sound and in a third aspect information is encoded by modulating light.", "An ( FIG. 3 c ) ultrasonic transducer ( 341 ) replaces the electromagnetic wave receiving coil on the implant ( 121 ) inside the eye.", "An ultrasonic transducer ( 342 ) replaces the coil outside the eye for the ultrasonic case.", "A transponder ( 343 ) under the conjunctiva of the eye may be used to amplify the acoustic signal and energy either direction.", "By piezoelectric effects, the sound vibration is turned into electrical current, and energy extracted therefrom.", "[0000] Modulated Light Beam [0118] For the light modulation ( FIG. 3 d ) case, a light emitting diode (LED) or laser diode or other light generator ( 361 ), capable of being modulated, acts as the information transmitter.", "Information is transferred serially by modulating the light beam, and energy is extracted from the light signal after it is converted to electricity.", "A photo-detector ( 362 ), such as a photodiode, which turns the modulated light signal into a modulated electrical signal, is used as a receiver.", "A set of a photo-generator and a photo-detector are on the implant ( 121 ) and a set is also external to the eye [0000] Prototype-Like Device [0119] FIG. 4 shows an example of the internal-to-the-eye and the external-to-the eye parts of the retinal color prosthesis, together with a means for communicating between the two.", "The video camera ( 401 ) connects to an amplifier ( 402 ) and to a microprocessor ( 403 ) with memory ( 404 ).", "The microprocessor is connected to a modulator ( 405 ).", "The modulator is connected to a coil drive circuit ( 406 ).", "The coil drive circuit is connected to an oscillator ( 407 ) and to the coil ( 408 ).", "The coil ( 408 ) can receive energy inductively, which can be used to recharge a battery ( 410 ), which then supplies power.", "The battery may also be recharged from a charger ( 409 ) on a power line source ( 411 ).", "[0120] The internal-to-the eye implanted part shows a coil ( 551 ), which connects to both a rectifier circuit ( 552 ) and to a demodulator circuit ( 553 ).", "The demodulator connects to a switch control unit ( 554 ).", "The rectifier ( 552 ) connects to a plurality of diodes ( 555 ) which rectify the current to direct current for the electrodes ( 556 );", "the switch control sets the electrodes as on or off as they set the switches ( 557 ).", "The coils ( 408 ) and ( 551 ) serve to connect inductively the internal-to-the-eye ( 500 ) subsystem and the external-to-the patient ( 400 ) subsystem by electromagnetic waves.", "Both power and information can be sent into the internal unit.", "Information can be sent out to the external unit.", "Power is extracted from the incoming electromagnetic signal and may be accumulated by capacitors connected to each electrode or by capacitive electrodes themselves.", "[0000] Simple Electrode Implant [0121] FIG. 6 a illustrates a set of round monopolar electrodes ( 602 ) on a substrate material ( 601 ).", "FIG. 7 shows the corresponding indifferent electrode ( 702 ) for these monopolar electrodes, on a substrate ( 701 ), which may be the back of ( 601 ).", "FIG. 6 b shows a bipolar arrangement of electrodes, both looking down onto the plane of the electrodes, positive ( 610 ) and negative ( 611 ), and also looking at the electrodes sideways to that view, positive ( 610 ) and negative ( 611 ), sitting on their substrate ( 614 ).", "Similarly for FIG. 6 c where a multipole triplet is shown, with two positive electrodes ( 621 ) and one negative electrode, looking down on their substrate plane, and looking sideways to that view, also showing the substrate ( 614 ).", "[0000] Epiretinal Electrode Array [0122] FIG. 8 a depicts the location of an epiretinal electrode array ( 811 ) located inside the eye ( 812 ) in the vitreous humor ( 813 ) located above the retina ( 814 ), toward the lens capsule ( 815 ) and the aqueous humor ( 816 );", "[0123] One aspect of the present embodiment, shown in FIG. 8 b , is the internal retinal color prosthetic part, which has electrodes ( 817 ) which may be flat conductors that are recessed in an electrical insulator ( 818 ).", "One flat conductor material is a biocompatible metallic foil ( 817 ).", "Platinum foil is a particular type of biocompatible metal foil.", "The electrical insulator ( 818 ) in one aspect of the embodiment is silicone.", "[0124] The silicone ( 818 ) is shaped to the internal curvature of the retina ( 814 ).", "The vitreous humor ( 813 ), the conductive solution naturally present in the eye, becomes the effective electrode since the insulator ( 818 ) confines the field lines in a column until the current reaches the retina ( 814 ).", "A further advantage of this design is that the retinal tissue ( 814 ) is only in contact with the insulator ( 818 ), such as silicone, which may be more inactive, and thus, more biocompatible than the metal in the electrodes.", "Advantageously, another aspect of an embodiment of this invention is that adverse products produced by the electrodes ( 817 ) are distant from the retinal tissue ( 814 ) when the electrodes are recessed.", "[0125] FIG. 8 c shows elongated epiretinal electrodes ( 820 ).", "The electrically conducting electrodes ( 820 ) says are contained within the electrical insulation material ( 818 );", "a silicon chip ( 819 ) acts as a substrate.", "The electrode insulator device ( 818 ) is shaped so as to contact the retina ( 814 ) in a conformal manner.", "[0000] Subretinal Electrode Array [0126] FIG. 9 a shows the location of a subretinal electrode array ( 811 ) below the retina ( 814 ), away from the lens capsule ( 815 ) and the aqueous humor ( 816 ).", "The retina ( 814 ) separates the subretinal electrode array from the vitreous humor ( 813 ).", "FIG. 9 b illustrates the subretinal electrode array ( 811 ) with pointed elongated electrodes ( 817 ), the insulator ( 818 ), and the silicon chip ( 819 ) substrate.", "The subretinal electrode array ( 811 ) is in conformal contact with the retina ( 814 ) with the electrodes ( 817 ) elongated to some depth.", "[0000] Electrodes [0000] Iridium Electrodes [0127] Now FIG. 10 will illuminate structure and manufacture of iridium electrodes ( FIGS. 10 a - e ).", "FIG. 10 a shows an iridium electrode, which comprises an iridium slug ( 1011 ), an insulator ( 1012 ), and a device substrate ( 1013 ).", "This embodiment shows the iridium slug electrode flush with the extent of the insulator.", "FIG. 10 b indicates an embodiment similar to that shown in FIG. 10 a , however, the iridium slug ( 1011 ) is recessed from the insulator ( 1012 ) along its sides, but with its top flush with the insulator.", "When the iridium electrodes ( 1011 ) are recessed in the insulating material ( 1012 ), they may have the sides exposed so as to increase the effective surface area without increasing geometric area of the face of the electrode.", "If an electrode ( 1011 ) is not recessed it may be coated with an insulator ( 1012 ), on all sides, except the flat surface of the face ( 1011 ) of the electrode.", "Such an arrangement can be embedded in an insulator that has an overall profile curvature that follows the curvature of the retina.", "The overall profile curvature may not be continuous, but may contain recesses, which expose the electrodes.", "[0128] FIG. 10 c shows an embodiment with the iridium slug as in FIG. 10 b , however, the top of the iridium slug ( 1011 ) is recessed below the level of the insulator;", "FIG. 10 d indicates an embodiment with the iridium slug ( 1011 ) coming to a point and insulation along its sides ( 1021 ), as well as a being within the overall insulation structure ( 1021 ).", "FIG. 10 e indicates an embodiment of a method for fabricating the iridium electrodes.", "On a substrate ( 1013 ) of silicon, an aluminum pad ( 1022 ) is deposited.", "On the pad the conductive adhesive ( 1023 ) is laid and platinum or iridium foil ( 1024 ) is attached thereby.", "A titanium ring ( 1025 ) is placed, sputtered, plated, ion implanted, ion beam assisted deposited (IBAD) or otherwise attached to the platinum or iridium foil ( 1024 ).", "Silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1012 ) or other insulator can adhere better to the titanium ( 1025 ) while it would not otherwise adhere as well to the platinum or iridium foil ( 1024 ).", "The depth of the well for the iridium electrodes ranges from 0.1 μm to 1 mm.", "[0000] Elongated Electrodes [0129] Another aspect of an embodiment of the invention is the elongated electrode, which are designed to stimulate deeper retinal cells, in one embodiment, by penetrating the retina.", "By getting closer to the target cells for stimulation, the current required for stimulation is lower and the focus of the stimulation is more localized.", "The lengths chosen are 100 microns through 500 microns, including 300 microns.", "FIG. 8 c is a rendering of an elongated epiretinal electrode array with the electrodes shown as pointed electrical conductors ( 820 ), embedded in an electrical insulator ( 818 ), where the elongated electrodes ( 817 ) contact the retina in a conformal manner, however, penetrating into the retina ( 814 ).", "[0130] These elongated electrodes, in an aspect of this of an embodiment of the invention may be of all the same length.", "In a different aspect of an embodiment, they may be of different lengths.", "Said electrodes may be of varying lengths ( FIG. 8, 817 ), such that the overall shape of said electrode group conforms to the curvature of the retina ( 814 ).", "In either of these cases, each may penetrate the retina from an epiretinal position ( FIG. 8 a , 811 ), or, in a different aspect of an embodiment of this invention, each may penetrate the retina from a subretinal position ( FIG. 9 b , 817 ).", "[0131] One method of making the elongated electrodes is by electroplating with one of an electrode material, such that the electrode, after being started, continuously grows in analogy to a stalagmite or stalactite.", "The elongated electrodes are 100 to 500 microns in length, the thickness of the retina averaging 200 microns.", "The electrode material is a substance selected from the group consisting of pyrolytic carbon, titanium nitride, platinum, iridium oxide, and iridium.", "The insulating material for the electrodes is a substance selected from the group silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide.", "[0000] Platinum Electrodes [0132] FIG. 11 ( a - e ) demonstrates a preferred structure of, and method of, making, spiked and mushroom platinum electrodes.", "Examining FIG. 11 a one sees that the support for the flat electrode ( 1103 ) and other components such as electronic circuits (not shown) is the silicon substrate ( 1101 ).", "An aluminum pad ( 1102 ) is placed where an electrode or other component is to be placed.", "In order to hermetically seal-off the aluminum and silicon from any contact with biological activity, a metal foil ( 1103 ), such as platinum or iridium, is applied to the aluminum pad ( 1102 ) using conductive adhesive ( 1104 ).", "Electroplating is not used since a layer formed by electroplating, in the range of the required thinness, has small-scale defects or holes which destroy the hermetic character of the layer.", "A titanium ring ( 1105 ) is next placed on the platinum or iridium foil ( 1103 ).", "Normally, this placement is by ion implantation, sputtering or ion beam assisted deposition (IBAD) methods.", "Silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1106 ) is placed on the silicon substrate ( 1101 ) and the titanium ring ( 1105 ).", "In one embodiment, an aluminum layer ( 1107 ) is plated onto exposed parts of the titanium ring ( 1105 ) and onto the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1106 ).", "In this embodiment the aluminum ( 1107 ) layer acts as an electrical conductor.", "A mask ( 1108 ) is placed over the aluminum layer ( 1107 ).", "[0133] In forming an elongated, non-flat, electrode ( FIG. 11 b ), platinum is electroplated onto the platinum or iridium foil ( 1103 ).", "Subsequently, the mask ( 1108 ) is removed and insulation ( 1110 ) is applied over the platinum electrode ( 1109 ).", "[0134] In FIG. 11 c , a platinum electrode ( 1109 ) is shown which is more internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring.", "The electrode ( 1109 ) is also thinner and more elongated and more pointed.", "FIG. 11 d shows a platinum electrode formed by the same method as was used in FIGS. 11 a , 11 b , and 11 c .", "The platinum electrode ( 1192 ) is more internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring as was the electrode ( 109 ) in FIG. 11 c .", "However it is less elongated and less pointed.", "[0135] The platinum electrode is internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring;", "said electrode whole angle at it's peak being in the range from 1° to 120°;", "the base of said conical or pyramidal electrode ranging from 1 micron to 500 micron;", "the linear section of the well unoccupied by said conical or pyramidal electrode ranging from zero to one-third.", "[0136] A similar overall construction is depicted in FIG. 1 e .", "The electrode ( 1193 ), which may be platinum, is termed a mushroom shape.", "The maximum current density for a given metal is fixed.", "The mushroom shape presents a relatively larger area than a conical electrode of the same height.", "The mushroom shape advantageously allows a higher current, for the given limitation on the current density (e.g., milliamperes per square millimeter) for the chosen electrode material, since the mushroom shape provides a larger area.", "[0000] Inductive Coupling Coils [0137] Information transmitted electromagnetically into or out of the implanted retinal color prosthesis utilizes insulated conducting coils so as to allow for inductive energy and signal coupling.", "FIG. 12 b shows an insulated conducting coil and insulated conducting electrical pathways, e.g., wires, attached to substrates at what would otherwise be electrode nodes, with flat, recessed metallic, conductive electrodes ( 1201 ).", "In referring to wire or wires, insulated conducting electrical pathways are included, such as in a “two-dimensional”", "“on-chip”", "coil or a “two-dimensional”", "coil on a polyimide substrate, and the leads to and from these “two-dimensional”", "coil structures.", "A silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1204 ) is shown acting as both an insulator and an hermetic seal.", "Another aspect of the embodiment is shown in FIG. 12 d .", "The electrode array unit ( 1201 ) and the electronic circuitry unit ( 1202 ) can be on one substrate, or they may be on separate substrates ( 1202 ) joined by an insulated wire or by a plurality of insulated wires ( 1203 ).", "Said separate substrate units can be relatively near one another.", "For example, they might lie against a retinal surface, either epiretinally or subretinally placed.", "Two substrates units connected by insulated wires may carry more electrodes than if only one substrate with electrodes was employed, or it might be arranged with one substrate carrying the electrodes, the other the electronic circuitry.", "Another arrangement has the electrode substrate or substrates placed in a position to stimulate the retinal cells, while the electronics are located closer to the lens of the eye to avoid heating the sensitive retinal tissue.", "[0138] In all of the FIGS. 12 a , 12 b , and 12 c , a coil ( 1205 ) is shown attached by an insulated wire.", "The coil can be a coil of wire, or it can be a “two dimensional”", "trace as an “on-chip”", "component or as a component on polyimide.", "This coil can provide a stronger electromagnetic coupling to an outside-the-eye source of power and of signals.", "FIG. 12 c shows an externally placed aluminum (conductive) trace instead of the electrically conducting wire of FIG. 12 d .", "Also shown is an electrically insulating adhesive ( 1208 ) which prevents electrical contact between the substrates ( 1202 ) carrying active circuitry ( 1209 ).", "[0000] Hermetic Sealing [0000] Hermetic Coating [0139] All structures, which are subject to corrosive action as a result of being implanted in the eye, or, those structures which are not completely biocompatible and not completely safe to the internal cells and fluids of the eye require hermetic sealing.", "Hermetic sealing may be accomplished by coating the object to be sealed with silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide.", "These materials also provide electrical insulation.", "The method and apparatus of hermetic sealing by aluminum and zirconium oxide coating is described in a pending U.S. patent application Ser.", "No. 08/994,515, now U.S. Pat. No. 6,043,437.", "The methods of coating a substrate material with the hermetic sealant include sputtering, ion implantation, and ion-beam assisted deposition (IBAD).", "[0000] Hermetic Box [0140] Another aspect of an embodiment of the invention is hermetically sealing the silicon chip ( 1301 ) by placing it in a metal or ceramic box ( 1302 ) of rectangular cross-section with the top and bottom sides initially open ( FIG. 13 ).", "The box may be of one ( 1302 ) of the metals selected from the group comprising platinum, iridium, palladium, gold, and stainless steel.", "Solder balls ( 1303 ) are placed on the “flip-chip”, i.e., a silicon-based chip that has the contacts on the bottom of the chip ( 1301 ).", "Metal feedthroughs ( 1304 ) made from a metal selected from the group consisting of radium, platinum, titanium, iridium, palladium, gold, and stainless steel.", "The bottom cover ( 1306 ) is formed from one of the ceramics selected from the group consisting of aluminum oxide or zirconium oxide.", "The inner surface ( 1305 ), toward the solder ball, ( 1303 )) of the feed-through ( 1304 ) is plated with gold or with nickel.", "The ceramic cover ( 1306 ) is then attached to the box using a braze ( 1307 ) selected from the group consisting of: 50% titanium together with 50% nickel and gold.", "Electronics are then inserted and the metal top cover (of the same metal selected for the box) is laser welded in place.", "[0000] Separate Electronics Chip Substrate and Electrode Substrate [0141] In one embodiment of the invention ( FIG. 14 ), the chip substrate ( 1401 ) is hermetically sealed in a case ( 1402 ) or by a coating of the aluminum, zirconium, or magnesium oxide coating.", "However, the electrodes ( 1403 ) and its substrate ( 1404 ) form a distinct and separate element.", "Insulated and hermetically sealed wires ( 1405 ) connect the two.", "The placement of the electrode element may be epiretinal, while the electronic chip element may be relatively distant from the electrode element, as much distant as being in the vicinity of the eye lens.", "Another embodiment of the invention has the electrode element placed subretinally and the electronic chip element placed toward the rear of the eye, being outside the eye, or, being embedded in the sclera of the eye or in or under the choroid, blood support region for the retina.", "Another embodiment of the invention has the electronic chip element implanted in the fatty tissue behind the eye and the electrode element placed subretinally or epiretinally.", "[0000] Capacitive Electrodes [0142] A plurality of capacitive electrodes can be used to stimulate the retina, in place of non-capacitive electrodes.", "A method of fabricating said capacitive electrode uses a pair of substances selected from the pair group consisting of the pairs iridium and iridium oxide;", "and, titanium and titanium nitride.", "The metal electrode acts with the insulating oxide or nitride, which typically forms of its own accord on the surface of the electrode.", "Together, the conductor and the insulator form an electrode with capacitance.", "[0143] Mini-capacitors ( FIG. 15 ) can also be used to supply the required isolating capacity.", "The capacity of the small volume size capacitors ( 1501 ) is 0.47 microfarads.", "The dimensions of these capacitors are individually 20 mils (length) by 20 mils (width) by 40 mils (height).", "In one embodiment of the invention, the capacitors are mounted on the surface of a chip substrate ( 1502 ), that surface being opposite to the surface containing the active electronics elements of the chip substrate.", "[0000] Electrode/Electronics Component Placement [0144] In one embodiment ( FIG. 16 a ), the internal-to-the-eye implanted part consists of two subsystems, the electrode component subretinally positioned and the electronic component epiretinally positioned.", "The electronics component, with its relatively high heat dissipation, is positioned at a distance, within the eye, from the electrode component placed near the retina that is sensitive to heat.", "[0145] An alternative embodiment shown in FIG. 16 b is where one of the combined electronic and electrode substrate units is positioned subretinally and the other is located epiretinally and both are held together across the retina so as to efficiently stimulate bipolar and associated cells in the retina.", "[0146] An alternative embodiment of the invention has the electronic chip element implanted in the fatty tissue behind the eye and the electrode element placed subretinally or epiretinally, and power and signal communication between them by electromagnetic means including radio-frequency (RF), optical, and quasi-static magnetic fields, or by acoustic means including ultrasonic transducers.", "[0147] FIG. 16 c shows how the two electronic-electrode substrate units are held positioned in a prescribed relationship to each other by small magnets.", "Alternatively the two electronic-electrode substrate units are held in position by alignment pins.", "Another aspect of this is to have the two electronic-electrode substrate units held positioned in a prescribed relationship to each other by snap-together mating parts, some exemplary ones being shown in FIG. 16 d. [0000] Neurotrophic Factor [0148] Another aspect of the embodiment is the use of a neurotrophic factor, for example, Nerve Growth Factor, applied to the electrodes, or to the vicinity of the electrodes, to aid in attracting target nerves and other nerves to grow toward the electrodes.", "[0000] Eye-Motion Compensation System [0149] Another aspect of the embodiment is an eye-motion compensation system comprising an eye-movement tracking apparatus ( FIG. 1 b , 112 );", "measurements of eye movement;", "a transmitter to convey said measurements to video data processor unit that interprets eye movement measurements as angular positions, angular velocities, and angular accelerations;", "and the processing of eye position, velocity, acceleration data by the video data processing unit for image compensation, stabilization and adjustment.", "[0150] Ways of eye-tracking ( FIG. 1 b , 112 ) include utilizing the corneal eye reflex, utilizing an apparatus for measurements of electrical activity where one or more coils are located on the eye and one or more coils are outside the eye, utilizing an apparatus where three orthogonal coils placed on the eye and three orthogonal coils placed outside the eye, utilizing an apparatus for tracking movements where electrical recordings from extra-ocular muscles are measured and conveyed to the video data processing unit that interprets such electrical measurements as angular positions, angular velocities, and angular accelerations.", "The video data processing unit uses these values for eye position, velocity, acceleration to compute image compensation, stabilization and adjustment data which is then applied by the video data processor to the electronic form of the image.", "[0000] Head Sensor [0151] Another aspect of the embodiment utilizes a head motion sensor ( 131 ).", "The basic sensor in the head motion sensor unit is an integrating accelerometer.", "A laser gyroscope can also be used.", "A third sensor is the combination of an integrating accelerometer and a laser gyroscope.", "The video data processing unit can incorporate the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion.", "[0000] Physician's Local Control Unit [0152] Another aspect includes a retinal prosthesis with (see FIG. 1 b ) a physician's local external control unit ( 115 ) allowing the physician to exert setup control of parameters such as amplitudes, pulse widths, frequencies, and patterns of electrical stimulation.", "The physician's control unit ( 115 ) is also capable of monitoring information from the implanted unit ( 121 ) such as electrode current, electrode impedance, compliance voltage, and electrical recordings from the retina.", "The monitoring is done via the internal telemetry unit, electrode and electronics assembly ( 121 ).", "[0153] An important aspect of setting up the retinal color prosthesis is setting up electrode current amplitudes, pulse widths, and frequencies so they are comfortable for the patient.", "FIGS. 17 a - c and FIGS. 18 a - c illustrate some of the typical displays.", "A computer-controlled stimulating test that incorporates patient response to arrive at optimal patient settings may be compared to being fitted for eyeglasses, first determining diopter, then cylindrical astigmatic correction, and so forth for each patient.", "The computer uses interpolation and extrapolation routines.", "Curve or surface or volume fitting of data may be used.", "For each pixel, the intensity in increased until a threshold is reached and the patient can detect something in his visual field.", "The intensity is further increased until the maximum comfortable brightness is reached.", "The patient determines his subjective impression of one-quarter maximum brightness, one-half maximum brightness, and three-quarters maximum brightness.", "Using the semi-automated processing of the patient-in-the-loop with the computer, the test program runs through the sequences and permutations of parameters and remembers the patient responses.", "In this way apparent brightness response curves are calibrated for each electrode for amplitude.", "Additionally, in the same way as for amplitude, pulse width and pulse rate (frequency), response curves are calibrated for each patient.", "The clinician can then determine what the best settings are for the patient.", "[0154] This method is generally applicable to many, if not all, types of electrode based retinal prostheses.", "Moreover, it also is applicable to the type of retinal prosthesis, which uses an external light intensifier shining upon essentially a spatially distributed set of light sensitive diodes with a light activated electrode.", "In this latter case, a physician's test, setup and control unit is applied to the light intensifier which scans the implanted photodiode array, element by element, where the patient can give feedback and so adjust the light intensifier parameters.", "[0000] Remote Physician's Unit [0155] Another aspect of an embodiment of this invention includes (see FIG. 1 b ) a remote physician control unit ( 117 ) that can communicate with a patient's unit ( 114 ) over the public switched telephone network or other telephony means.", "This telephone-based pair of units is capable of performing all of the functions of the of the physician's local control unit ( 115 ).", "[0000] Physician's Unit Measurements Menus and Displays [0156] Both the physician's local ( 115 ) and the physician's remote ( 117 ) units always measure brightness, amplitudes, pulse widths, frequencies, patterns of stimulation, shape of log amplification curve, electrode current, electrode impedance, compliance voltage and electrical recordings from the retina.", "[0157] FIG. 17 a shows the main screen of the Physician's Local and Remote Controller and Programmer.", "FIG. 17 b illustrates the pixel selection of the processing algorithm with the averaging of eight surrounding pixels chosen as one element of the processing.", "FIG. 17 c represents an electrode scanning sequence, in this case the predefined sequence, A. FIG. 17 d shows electrode parameters, here for electrode B, including current amplitudes and waveform timelines.", "FIG. 17 e illustrates the screen for choosing the global electrode configuration, monopolar, bipolar, or multipolar.", "FIG. 17 f renders a screen showing the definition of bipolar pairs (of electrodes).", "FIG. 17 g shows the definition of the multipole arrangements.", "[0158] FIG. 18 a illustrates the main menu screen for the palm-sized test unit.", "FIG. 18 b shows a result of pressing on the stimulate bar of the (palm-sized unit) main menu screen, where upon pressing the start button the amplitudes A 1 and A 2 are stimulated for times t 1 , t 2 , t 3 , and t 4 , until the stop button is pressed.", "FIG. 18 c exhibits a recording screen that shows the retinal recording of the post-stimulus and the electrode impedance.", "[0159] FIGS. 19 a , 19 b , and 19 c show different embodiments of the Physician's Remote Controller, which has the same functionality inside as the Physician's Local Controller but with the addition of communication means such as telemetry or telephone modem.", "[0000] Patient's Controller [0160] Corresponding to the Physician's Local Controller, but with much less capability, is the Patient's Controller.", "FIG. 20 shows the patient's local controller unit.", "This unit can monitor and adjust brightness ( 2001 ), contrast ( 2002 ) and magnification ( 2003 ) of the image on a non-continuous basis.", "The magnification control ( 2003 ) adjusts magnification both by optical zoom lens control of the lens for the imaging means ( FIG. 1, 111 ), and by electronic adjustment of the image in the data processor ( FIG. 2, 113 ).", "[0161] While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims." ]
RELATED CASES The present application claims the benefit of Provisional Patent Application Ser. No. 60/442,281, for “Characterization of Liquids Using Gas Bubbles” filed on Jan. 24, 2003. FIELD OF THE INVENTION The present invention relates generally to characterization of liquids and, more particularly, to the determination of certain properties of a liquid by measuring characteristics of bubbles formed therein. BACKGROUND OF THE INVENTION The dynamics of gas bubbles in liquids has been studied using a variety of optical and acoustic techniques for industrial applications and for basic physics research. High-speed photography (See, e.g., T. G. Leighton, The Acoustic Bubble . (Academic Press, London, 1994), pp. 119–207; H. C. Pumphrey and A. J. Walton, “Experimental study of the sound emitted by water drops impacting on a water surface,” European Journal of Physics, 9(3), 225–231 (1988); and P. Di Marco et al., “Experimental Study on Terminal Velocity of Nitrogen Bubbles” in FC-72, Proc. Experimental Heat Transfer, Fluid Mechanics and Thermodynamics 2001, ed. by G. P. Celata et al., GR, Sep. 24–28, 2001, ETS, Pisa, pp. 1349–1359.) is the most widely used technique, but requires complex image processing to extract quantitative information about bubble behavior. Laser Doppler anemometry (See, e.g., R. Mahalingam et al., “Velocity measurements in Two-Phase Bubble-Flow Regime with Laser-Doppler Anemometry,” J. Am. Inst. Chem. Eng. 22, 1152–1155 (1976).) has been used to study bubble terminal velocity, and the laser-Schlieren (See, e.g., D. S. Hacker and F. D. Hussein, “The Application of a Laser-Schlieren Technique to the Study of Single Bubble Dynamics,” Ind. Eng. Chem. Fund. 17(4), 277–283 (1978).) technique has been used to study bubble shape and terminal velocities. Optical interferometry (See, e.g., A. Gelmetti et al., “An optical interferometer for gas bubble measurements,” Rev. Sci. Instrum. 67(10), 3564–3566 (1996); and L. Rovati et al., 64 (6), 1463–1467 (1993).) has found use in the study of bubble oscillations in a sound field. These optical techniques require both a transparent liquid and window access to the liquid through the container. Radio-frequency probes (See, e.g., N. Abuaf et al., “Radio-frequency probe for bubble size and velocity measurements,” Rev. Sci. Instrum. 50(10), 1260–1263 (1979).) have also been used to investigate bubble size and terminal velocity. Passive listening (See, e.g., T. G. Leighton and A. J. Walton, “An experimental study of the sound emitted from gas bubbles in a liquid”, Euro. J. Phys. 8, 98–104 (1987).) at acoustic frequencies is typically used to study bubble resonance. Ultrasonic pulsed Doppler procedures have been used for bubble detection (See, e.g., R. Y. Nishi, “Ultrasonic detection of bubbles with Doppler flow transducers,” Ultrasonics, 10, 173–179 (1972).) and terminal velocity measurements (See, e.g., H. Kellerman et al., “Dynamic modeling of gas-hold-up in different electrolyte systems,” J. Appl. Electrochem. 28, 311–319 (1998).). Typically, the above-mentioned techniques are used to study only one or two aspects of the behavior of bubbles. There are three principal stages to the evolution of a gas bubble: (1) formation and growth at the tip of a nozzle located in a liquid; (2) detachment and resonance; and (3) ascent to terminal velocity. In the first stage of evolution, the bubble grows to a specific size at the opening of the nozzle, the radius of the nozzle opening and the properties of the surrounding liquid determining the ultimate size of the bubble (See, e.g. M. S. Longuet-Higgins, B. R. Kerman, and K. Lunde, “The release of air bubbles from an underwater nozzle,” J. Fluid Mech. 230 (1991) p365–390.) As the bubble pinches off and detaches from the nozzle, it resonates (breathing-mode) briefly at a natural frequency determined primarily by its radius and the liquid density. The frequency f 0 of this resonance oscillation was first calculated by M. Minnaert in “On Musical Air-Bubbles and the Sounds of Running Water,” Phil. Mag. 16, 235–248 (1933) to be: f 0 = 1 2 ⁢ π ⁢ ⁢ R 0 ⁢ 3 ⁢ γ ⁢ ⁢ p 0 ρ , ( 1 ) where R 0 is the radius of the bubble, γ is the ratio of specific heat at constant pressure to the specific heat at constant volume of the gas, ρ 0 is the hydrostatic pressure of surrounding liquid, and ρ is the liquid density. This equation is reasonably accurate for the mm-sized bubbles. For significantly smaller bubbles, Equ. 1 must be modified to account for the effects of surface tension (See, T. G. Leighton, supra). The bubble resonance can be detected and quantified using a hollow cylindrical piezoelectric transducer surrounding the bubble. After detachment from the nozzle, the bubble accelerates to its terminal velocity which depends on the size of the bubble. For low viscosity fluids, such as water, the behavior of the rising bubble falls within several regions. Small bubbles (less than 0.035 cm radius) are spherical and rise substantially vertically at a speed determined by Stokes' Law. Larger bubbles (0.035 cm to 0.07 cm), have internal air circulation, which reduces shear stresses at the interface leading to a velocity higher than predicted by Stokes' Law. Between 0.07 cm and 0.3 cm, bubbles are elliptical and follow a spiral or zigzag path. Drag increases due to vortex formation in the bubble wake. Bubbles greater than 0.3 cm form spherical cap shapes (See, e.g., L.-S. Fan and K. Tsuchiya, Bubble Wake Dynamics in Liquids and Liquid - Solid Suspensions (Butterworth-Heinemann, Boston, 1990), pp. 36–43.). The terminal velocity U 0 depends on the buoyant and drag forces on the bubble (See, H. Kellerman et al., supra): U 0 = 8 3 ⁢ gR 0 C D , ( 2 ) where g is the acceleration due to gravity, R 0 is the radius of the bubble and C D is the drag coefficient. The drag coefficient depends on physical properties of the liquid and the size of the bubble. A theory by G. Bozzano and M. Dente, “Shape and terminal velocity of single bubble motion: a novel approach,” Computers & Chemical Engineering. 25 (2001) 571–576, is useful for calculating the drag coefficient because it covers a wide range of bubble sizes and liquid properties. The drag coefficient is calculated using Reynolds, Eotvos, and Morton numbers, which depend on the surface tension, density, and viscosity of the liquid and the bubble size. An equation for terminal velocity applicable for air bubbles between 0.07 cm and 0.3 cm is given by (See L.-S Fan and K. Tsuchiya, supra): U 0 = c ⁢ ⁢ σ R 0 ⁢ ⁢ ρ , ( 3 ) where c=1.8 for a single component liquid (c is between 1.0 and 1.4 for mixtures). The presence of contaminants (e.g., surfactants, suspended particles) has a significant effect on the rise of the bubble due to the Marangoni effect and the immobilization of the air-liquid interface (See, e.g., G. Liger-Belair et al., “On the Velocity of Expanding Spherical Gas Bubbles Rising in Line in Supersaturated Hydroalcoholic Solutions: Application to Bubble Trains in Carbonated Beverages,” Langmuir 16, 1889–1895 (2000).). The path of the rising bubbles is largely determined by the Reynolds number, N R . For low Reynolds numbers (N R <130), the bubble travels substantially vertically. For higher Reynolds numbers (130<N R <400), the tip of the wake behind the bubble becomes unstable and oscillates at a low frequency, leading to a zigzag path. For even higher Reynolds numbers (400<Re<350,000), vortices are periodically shed from alternate sides of the bubble on a plane that slowly revolves around the bubble, leading to a spiral path (See T. G. Leighton, supra). As the mm-sized bubble rises, it also undergoes shape oscillations (P. Di Marco et al., supra). The frequency of these oscillations (See T. G. Leighton, supra) is given by: f n = 1 2 ⁢ π ⁢ ( n - 1 ) ⁢ ( n + 1 ) ⁢ ( n + 2 ) ⁢ σ ρ ⁢ ⁢ R 0 3 , ( 4 ) where f n is the frequency of oscillations, n is the mode number, and σ is the surface tension. Both terminal velocity and shape oscillations can be monitored by observing the Doppler frequency shift of sound reflected from the bubble. The speed, U, of the bubble is related to the speed of sound, the frequency of the sound source used to interrogate the bubble, and the frequency received by the detector utilized for the measurement according to: U = v ⁢ ( f r - f s ) ( f r + f s ) , ( 5 ) where ν is the liquid sound speed, f r is the received frequency, and f s is the source frequency (See, e.g., D. G. H. Andrews, “An experiment to demonstrate the principles and processes involved in medical Doppler ultrasound,” Phys. Educ. 35(5), 350–353 (2000)). Accordingly, it is an object of the present invention to provide an apparatus and method for measuring liquid characteristics from the properties of bubbles formed therein. Additional objects, advantages and novel features of the invention will be set forth, in part, in the description that follows, and, in part, will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. SUMMARY OF THE INVENTION To achieve the foregoing and other objects, and in accordance with its purposes of the present invention, as embodied and broadly described herein, the method for measuring liquid properties hereof includes: forming a bubble in the liquid; measuring the resonance frequency of the bubble; measuring the shape oscillation frequency of the bubble; and measuring the terminal velocity of the bubble in the liquid. In another aspect of the invention and in accordance with its objects and purposes, the apparatus for measuring liquid properties hereof includes: means for forming a bubble in the liquid; means for measuring the resonance frequency of the bubble; means for measuring the shape oscillation frequency of the bubble; and means for measuring the terminal velocity of the bubble in the liquid. Benefits and advantages of the present invention include, but are not limited to, the noninvasive, inexpensive measurement of liquid density, surface tension and viscosity, and the monitoring of changes in these quantities. It should be mentioned that the invention is applicable to opaque liquids. Moreover, by making simultaneous passive listening and active Doppler measurements on a bubble, all aspects of the bubble evolution (bubble formation, growth, detachment and resonance, shape oscillations, terminal velocity, and rise path) can be observed which permits liquid properties to be determined. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and form a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings: FIG. 1 is a schematic representation of the resonance-Doppler apparatus of the present invention showing a pump for injecting a gas into a chamber through a syringe needle, thereby producing a bubble; a cylindrical transducer disposed around the tip of the needle for detecting the sound generated both when the bubble forms and when it detaches; a Doppler probe disposed above the needle for monitoring the growth and rise of the bubble (T=transmitter, R=receiver); and a computer for analyzing the digitized output of both of these sensors. FIG. 2 is a schematic representation of an embodiment of the Doppler probe measurement electronics used in cooperation with the present resonance-Doppler apparatus, showing a local oscillator for exciting the transmitter of the Doppler probe at 10 MHz; an amplifier for amplifying the signal produced by the Doppler probe in response to the reflected sound from the rising bubble; a high-pass filter for reducing noise, the output therefrom being mixed with the local oscillator signal to produce sum and difference frequencies; and a low-pass filter for removing the sum frequency, leaving the difference, or Doppler, frequency. FIG. 3 is a schematic representation of a noninvasive embodiment of the resonance-Doppler apparatus of the present invention showing a piezoelectric ring (section) transducer disposed externally to a pipe or container bearing the liquid for generating focused, high intensity sound coaxially with the pipe and having sufficient intensity to generate bubbles, one at a time, by a cavitation process in the liquid; a function generator for producing tone bursts of sine-waves having a frequency matching the thickness mode resonance of the wall of the container; and an externally located Doppler probe for measuring the rate of ascent of the bubbles formed. FIG. 4 a illustrates signals detected during the evolution of a bubble, the black line representing the initial resonance signal detected by the cylindrical transducer, and the grey line representing the signal from the Doppler probe, the bubble forming at the tip of the needle at t 1 , growing until t 2 when it detaches from the needle, rising and ultimately reaching terminal velocity; and FIG. 4 b shows the bubble velocity as a function of time. FIG. 5 a shows the Fourier transform of a bubble resonance signal for two different water heights; and FIG. 5 b shows the bubble velocity as a function of time for the two heights. FIG. 6 is a long pathlength Doppler measurement for a single bubble rising in a spiral path. FIG. 7 a are Fourier transforms of bubble resonance signals for two air flows; while FIG. 7 b shows the bubble velocity as a function of time for the two flow rates of FIG. 7 a hereof. FIG. 8 a are Fourier transforms of bubble resonance signals when a surfactant is added to water compared with those for pure water; while FIG. 8 b shows the bubble velocity as a function of time for the two liquids. FIG. 9 a are Fourier transform of bubble resonance signals resulting when isopropyl alcohol is added to water, compared with those for pure water; while FIG. 9 b shows the bubble velocity as a function of time for the two liquids. FIG. 10 a are Fourier transforms of bubble resonance signals when particles are suspended in water compared with those for pure water; while FIG. 10 b shows the bubble velocity as a function of time for the two liquids. DETAILED DESCRIPTION Briefly, the present invention includes a method for determining surface tension, density and viscosity of a liquid, and for monitoring changes in these characteristics by measuring the resonance frequency, terminal velocity and shape oscillation frequency for bubbles formed in the liquid under investigation. Bubbles are formed in the liquid using forced air flow from a syringe tip; however, it is anticipated that a cavitation process in the liquid induced by the application of ultrasound to the liquid can be used as well. Additionally, other gases can be employed to form bubbles in situations where the liquid is sensitive to oxygen. From Eq. 1 hereinabove, it is seen that the resonance frequency of a bubble is related to γ which is the ratio of the specific heat of the gas at constant pressure to the specific heat thereof at constant volume, the value of which depends on the nature of the gas. For example, for monotomic gases, γ=1.67, for diatomic gases, γ=1.41, while for polyatomic gases γ=1.3. Therefore, the resonant frequency of the bubble will depend on the gas being used for its generation. The terminal velocity and the shape oscillation frequency for the bubble are not affected by the choice of gas. Typically, when bubbles are generated using cavitation, the vapor inside the bubble will be the vapor of the liquid that is cavitating. However, if gas is dissolved in the liquid, a portion of this gas may enter the bubble. In fact, dissolved gases lower the threshold for cavitation. Additionally, under certain circumstances the identity of the dissolved gas can be determined from the resonance frequency. As long as a consistent set of bubble measurements is used in the analysis in accordance with the present invention; that is, measurements taken using either the cavitation method or the syringe method for bubble formation, the above-mentioned properties of the liquid can be determined. Although analytic algorithms are provided hereinbelow for extracting or monitoring the desired characteristics of the liquid from the three measured quantities, more general versions of Equations 1–4 can be parametrically solved numerically to extract these characteristics. The present method is not restricted to optically transparent liquids, and the quantities can be measured using technology found in references listed hereinabove. One embodiment of the invention includes: (1) passive listening using acoustic technology to measure bubble resonance frequency; and (2) an active Doppler (Joint Time-Frequency Analysis) method to measure bubble terminal velocity and shape oscillation frequency. Since these quantities are affected by the physical properties of the surrounding liquid (that is, surface tension, density, viscosity), the liquid can be characterized and monitored from measurements on bubbles formed therein. Equations (1)–(4) show the relationship of bubble resonance frequency, terminal velocity, and shape oscillation frequency to the surface tension and density of the host liquid. Rearranging these equations, the above physical properties of the liquid determined from observable quantities are as follows: ρ = 0.350 ⁢ cf n 2 ⁢ p 0 f 0 2 ⁢ U 0 2 ( 6 ) R 0 = 0.551 ⁢ U 0 f s ⁢ c ( 7 ) σ = 0.193 ⁢ f n ⁢ U 0 ⁢ p 0 f 0 2 ⁢ c ( 8 ) For small bubbles, where Stokes' Law applies, the viscosity is inversely proportional to terminal velocity. Therefore, the viscosity of the liquid can also be determined from the terminal velocity, once the system is calibrated using a liquid having known viscosity (Calibration may not be necessary since viscosity can be determined from bubble resonance frequency and terminal velocity. Liquid viscosity η is inversely proportional to the product of square of the resonance frequency and the terminal velocity as η∝1/(f 0 2 U 0 )). The viscosity and the resonance frequency are the two measured parameters. Equation 9 below provides a more quantitative relationship among the measured parameters in order to experimentally determine viscosity η = 0.0236 ⁢ gp 0 f 0 2 ⁢ U 0 . ( 9 ) The parameters g, p 0 , f 0 , and U 0 are defined hereinabove. The dynamics of bubble rise through any liquid is a function of bubble size which in turn depends on liquid properties such as density and surface tension. Equations (6)–(8) faithfully represent the behavior of bubbles having a range of sizes below a cut-off value. To provide a bubble size for comparison among various liquids, a dimensionless number called the Eotvos number is used. The Eotvos number takes into account liquid density and surface tension to normalize the bubble size. Although the above equations (which are used principally because of their simplicity of form) are strictly valid for liquids having an Eotvos number ≦50, a large range of bubble sizes can be accommodated by numerically solving more general equations. The method of the present invention is expected to be useful for Eotvos numbers ≦50. For water, this condition defines a bubble having a radius of approximately 7 mm. Reference will now be made in detail to the present preferred embodiments of the invention examples of which are illustrated in the accompanying drawings. In what follows, identical callouts will be used for similar or identical structure. Turning now to FIG. 1 , hereof, a schematic representation of the apparatus, 10 , used to demonstrate the present method is shown. In this embodiment of the invention, bubbles are generated by forcing air from air pump, 12 , through metal syringe, 14 . The flow-rate was adjustable both using valve, 16 , and by changing the air pressure delivered by the pump. The syringe needle was inserted through the closed bottom portion of a vertically oriented plastic tube, 18 , which served as the container for the liquids, 20 , investigated. The tube was generally filled to 6 cm above the syringe needle, and measurements were made using water nominally at 20° C., the ambient room temperature. Clearly, bubbles can be formed using other gases, and the present apparatus can be used to investigate the associated liquid. The size of the orifice of the syringe is unimportant. Although the initial size of the bubble changes with orifice size, and the measured properties scale with the bubble size, so long as the bubble size is consistent with the discussion of the Eotvos number, hereinabove (as an example, for water, the bubble diameter should be less than about 7 mm), the liquid parameters derived from these measured properties are unaffected. Hollow cylindrical piezoelectric transducer (2.55-cm long, 2.30-cm inner diameter, 1.20-mm thick, Boston Piezo-Optics, Mass.), 22 , was disposed symmetrically around the tip of the syringe to enable detection of sound produced by bubble, 24 , in many directions. Traditionally, such resonance measurements are made from one side using a hydrophone. The transducer output was amplified using amplifier, 26 . A frequency-mixing-based Doppler apparatus which includes Doppler probe, 28 , controlled by Doppler circuitry, 30 , was used to monitor the speed of ascending bubble 24 as a function of time. The outputs of both the cylindrical transducer and circuitry 30 were directed to a 2-channel, digital storage oscilloscope (DSO), 32 , which digitized the data and transferred it to computer, 34 , for analysis. Doppler circuitry 30 is schematically described in FIG. 2 hereof. Function generator, 36 , provides ultrasonic excitation for transmitter, 38 , of dual-element Doppler probe (9.4 MHz, 10-cm long, 9.5-mm diameter, Parks Medical Pencil Probe), 28 , normally placed about 4 cm above the tip of syringe 14 . Receiver, 40 , of the Doppler probe 28 detects the sound reflected from ascending bubble 24 . Amplifier, 42 , and high-pass filter, 44 , are used to process the signal received by receiver 40 before it is mixed with the signal input to transmitter 38 using mixer, 46 , to produce sum and difference frequencies. Low-pass filter, 48 , permits the Doppler difference frequency to be obtained from the mixer. It is this difference frequency that is related to the bubble velocity and shape oscillations as will be discussed hereinbelow. Doppler probe 28 is shown in FIG. 1 hereof to include a pair of tilted transducers which are angled downwards ( 38 , 40 ) to monitor the ascent of the bubbles; the probe utilized was a commercially available medical Doppler transducer probe designed for viewing veins under close-focusing conditions. FIG. 3 hereof is a schematic representation of a noninvasive embodiment of the resonance-Doppler method of the present invention. In this embodiment, both the bubble generation and bubble detection are achieved externally to the pipe or cylindrical container bearing the liquid under investigation. Piezoelectric ring transducer, 50 , which can either be a complete ring or two half-rings that are in electrical connection is used to generate high intensity sound at the center and on the axis of the pipe. The curvature of the container focuses sound at the axis of the container. Function generator, 52 , produces tone bursts of sine-waves having a frequency that matches the thickness mode resonance of the wall of the container. Frequency matching permits the sound to be transmitted through the wall with the maximum efficiency. The frequency used can be either at the fundamental frequency or higher harmonics of the wall thickness mode resonance frequency. A broad range of acoustic frequencies can be used, but sound transmission through the wall may vary. The burst frequency, duration, and duty cycle can be adjusted for a chosen bubble generation rate. The output of the function generator is amplified by power amplifier, 54 , before being applied to the transducer. By adjusting the power, frequency, burst duration, and duty cycle it is also possible to create a single bubble in the liquid inside the pipe or container by the cavitation process (See, e.g., T. G. Leighton, The Acoustic Bubble (Academic Press, London, 1994), 504–506). Passive or active circuit directional coupler, 56 , allows the same transducer to be used for both generating bubbles by cavitation, and for detecting the bubble resonance. The bubble resonance signal detected by cavitation transducer 50 is amplified by signal amplifier, 58 , before being directed to multiplexer, 60 , and digitized using A/D converter, 62 . The resonance signal is generated when the burst signal is off. Microcontroller, 64 controls function generator 52 and multiplexer 60 as well as processing the signals received from both Doppler probe 28 and cavitation transducer 50 . The tilt of elements 38 and 40 of Doppler probe 28 shown in FIG. 1 , hereof is not a requirement of the present invention; rather, a flat-surfaced, concentric transducer head having an outer ring surrounding an inner disk, where one transducer serves as the transmitter and the other as a receiver, will provide a symmetric sound beam pattern without focusing. This permits a longer viewing range for the bubble; that is, the received signal has been observed by the present inventor to be strong along the entire path of the bubble instead of only in the focused beam intersection region of the two tilted transducers. The transducers for noninvasive measurements are acoustically coupled to the wall (a coupling medium can be employed to improve the acoustic coupling), and the resulting sound waves are directed (refracted) at an angle into the liquid inside. The Doppler probe frequency can be chosen to match a higher harmonic of the wall resonance frequency, allowing maximum sound transmission. The Doppler frequency is chosen to be greater than 5 MHz and, more typically, it is above 10 MHz. The received signal from the cavitation transducer, and the amplified output from mixer/amplifier/filter, 66 , are directed through multiplexer 60 to A/D converter 62 before entering microcontroller 64 for signal processing. The microcontroller is capable of performing rapid Fast Fourier Transform (FFT) and Short-Time Fourier Transform (STFT) calculations using the bubble resonance signal and the Doppler signal as will be described in more detail hereinbelow. The bubble resonance signal from the cylindrical transducer (as shown in FIG. 1 hereof) was transformed using FFT to obtain the frequency spectrum of the resonance of the bubble. The Doppler signal, by contrast, was analyzed using Joint Time-Frequency Analysis (JTFA), which is a technique in which the frequency components of a signal are displayed as a function of time. As result, signal changes, such as a time-dependent Doppler frequency, can be observed, thereby permitting the speed of the bubble to be determined as a function of time during the period of growth and rise. JTFA was performed using either the Short-Time Fourier Transform method (STFT) or the Continuous Wavelet Transform (CWT) procedure (See, e.g., S. Qian and D. Chen, Joint Time-Frequency Analysis . (Prentice Hall PTR, Upper Saddle River, 1996), pp. 45–52), both of which gave the same time-dependent velocity information. Measurements were made at various temperatures, airflow rates, liquid heights, and transducer positions. Water temperature was measured using a digital thermometer with a 0.1° C. resolution. The effect of liquid height was evaluated by changing the amount of liquid in the container. Doppler measurements were performed at various probe heights above the syringe (See FIG. 1 hereof). A height of ˜2.5 cm was used to study bubble formation, whereas a height of ˜10 cm was used to study the ascent path of the bubble. The effect of liquid contaminants was also examined. To determine the effects of surfactant contaminants, a 1% solution (by volume) of dishwashing soap in water was used. Solutions of isopropyl alcohol and water at various concentrations (with the highest concentration being 66% water, 34% alcohol by volume) were used to investigate the effect of organic chemical contaminants on the bubbles. A dilute suspension (˜1 g/L) of turmeric particles (10 to 100 μm, having irregular shapes) in water was used to investigate the effect of suspended particles on bubble behavior. Turmeric was chosen because it provided a stable suspension. Turning now to the measurements made in accordance with the present invention, FIG. 4 a shows the signals from the cylindrical transducer and Doppler probe, whereas FIG. 4 b shows the STFT of the Doppler signal, expressed as bubble velocity, which is proportional to the measured frequency difference. The measurement was made with the Doppler probe located 2.5 cm above the syringe. At time t 1 , a small spike in the resonance signal (cylindrical transducer output) was observed, which is most likely due to a meniscus forming at the tip of the syringe ( FIG. 4 a ). From time t 1 to time t 2 , the bubble enlarged on the tip of the syringe. The growth process commenced with a rapid expansion of the bubble upward followed by horizontal growth. This was observed in the Doppler signal as an initial speed of 0.1 m/s at t 1 which decreased to 0.05 m/s. At t 2 the bubble detaches and begins to resonate, as indicated by a rapid increase in the speed (higher frequency Doppler signal) and an associated burst in the resonance signal. After t 2 the bubble accelerated to its terminal velocity while undergoing shape oscillations as observed by the oscillations in the STFT signal in FIG. 4 b . The shape oscillation frequency has been observed to remain constant over time unless the properties of the liquid change with height; for example, if the liquid is stratified it may have a density gradient which varies as a function of height. In this situation, one would observe a variation in the shape oscillation frequency and the terminal velocity of the bubble. With the exclusion of FIG. 6 , the graphs labeled with (a) in the following figures show FFTs of the signal from the cylindrical transducer, whereas the graphs labeled with (b) show STFTs of the Doppler signal. The STFT is shown as a two-dimensional plot of velocity over time, with the degree of darkness indicating the magnitude of the Doppler signal. The Resonance-Doppler measurements in the narrow temperature range studied (between 0° C. and 8° C.), show only a small effect of temperature on the bubble behavior (i.e., formation, growth, resonance, and rise). FIG. 5 shows that an increase in water height decreases the bubbling rate and the width of the resonance. These changes are due to the differences in the hydrostatic pressure. As stated, the two transducers of the medical Doppler probe employed were slightly angled towards each other, which resulted in a focused beam directed below the probe (T and R in FIG. 1 ). Therefore, the probe detects the ascending bubble in a region directly below it. When the probe was positioned close to the tip of the syringe (e.g., about 4 cm), only the formation of the bubble and the start of its ascent can be adequately observed. When the probe at was located at approximately 10 cm, later periods of the ascent were found to be observable, including the nature of the rise path (e.g., straight, zigzag, or spiral). FIG. 6 shows how a spiral ascent path of the bubble affects the STFT data. For example, the oscillations in the velocity and the variations in the amplitude of the STFT of the Doppler signal (darkness of the plot) are due to the bubble moving in and out of the beam of the Doppler probe. A flat, concentric arrangement of the transducer elements having greater beam spread was also used, allowing more of the bubble's ascent to be observed (See FIG. 6 hereof). As the flow rate of air increases, the bubble size remains relatively constant, as indicated by the fact that the resonance frequency does not change. At greater airflow rates, the bubble resonance is larger in amplitude ( FIG. 7 a ), probably due a stronger axial jet from a faster detachment from the nozzle (See T. G. Leighton and A. J. Walton, supra). Moreover, the number of bubbles released per second increases, as is observed by the increased number of bubble detachments in a given length of time ( FIG. 7 b ). The presence of surfactant was found to have a pronounced effect on many aspects of the evolution of the bubbles. For example, the bubble resonance moves to a higher frequency and becomes more damped ( FIG. 8 a ). The increase in the resonance frequency is due to the smaller size of the bubbles (see Eq. 1). The bubbles are smaller in the soap solution than in plain water since they detach sooner because of the lower surface tension. Other effects include the following: the terminal velocity was less than half of the terminal velocity in pure water, the bubbling rate increased by greater than a factor of two, and the shape oscillations became too small to be easily determined ( FIG. 8 b ). These observations are likely due to the presence of surfactant molecules at the air-liquid interface. The increase in resonance peak width is likely due to the higher viscosity of the soap solution. Other contaminants, such as alcohol, also have a substantial change on the bubble's evolution. For example, the presence of isopropyl alcohol shifts the resonance peak to a higher frequency and increases the damping ( FIG. 9 a ). In addition, the terminal velocity is significantly reduced, the bubbling rate increases, and the shape oscillations becomes smaller ( FIG. 9 b ). The period of bubble growth is also shorter, showing that the bubbles detach from the nozzle sooner. These effects are very similar to those observed with the surfactant. This is likely due to the fact that both alcohol and soap lower the surface tension of the water, and the higher viscosity of the isopropyl alcohol concentration leads to a wider resonance peak width. FIG. 10 shows the effect of suspended particles (turmeric), in water. The suspended particles have little observable effect on the resonance of the bubble ( FIG. 10 a ); however, the rise is affected. Instead of traveling along a wide spiral path upwards, as in the case of uncontaminated water, it was observed that the bubbles follow a tight spiral around the axis of the cylindrical test chamber. Moreover, the shape oscillations decay rapidly becoming too small to measure. These changes likely occur because the suspended particles adhere to the air-water interface of the bubble, thereby stiffening the boundary and increasing the effective viscosity (See L.-S. Fan and K. Tsuchiya, supra) TABLE 1 summarizes the experimental results of various aspects of bubble dynamics and compares some of the results with theoretical predictions. TABLE 1 Bubble Shape Terminal Bubbling Radius oscillation velocity rate (mm) Freq. (Hz) (m/s) (bub./s) Water (Exp.) 1.44 ± 0.05 86.7 ± 5.5  0.311 ± 0.009 ~2 (Theor. Pred.) 1.23  92.6 0.295 — Alcohol (Exp.) 1.05 ± 0.02  100 ± 9.5  0.192 ± 0.008 ~4 (Theor. Pred.) 1.00 104   0.228 N/A Soap (Exp.) 1.12 ± 0.09 None 0.190 ± 0.006 ~6 Turmeric 1.42 ± 0.07 None 0.248 ± 0.051 ~2 (Exp.) Equation 1 is used to calculate the experimental bubble size from its resonance frequency. For theoretical predictions of bubble size, see e.g., M. S. Longuet-Higgins et al., supra, which describes bubble formation at low flow rates. This is not the situation for the present measurements, which may be the cause for the observed differences between the theoretical and the measured bubble sizes. The frequency of the shape oscillations in the time-frequency plots is determined by averaging the period of four oscillations and taking the reciprocal. The theoretical frequencies (Eq. 3) are determined for a second-order (n=2, ellipsoidal) oscillation and agree well with experimental values for water and the alcohol/water mixture. The alcohol/water mixture shows a higher shape oscillation frequency because of the smaller bubble radius as compared with plain water. No shape oscillations could be easily discerned with the other contaminants. The theory by G. Bozanno and M. Dente, supra, was used to determine the drag coefficient from the terminal velocity, which is in turn used in Eq. (2). The decrease in the terminal velocity of the isopropyl alcohol/water mixture is consistent with theory (smaller bubble radius). Thus, by measuring the evolution of the bubble (bubble resonance, terminal velocity, and shape oscillations), certain physical properties of the liquid can be measured and monitored. For example, surface tension can be determined from the bubble radius, which is in turn derived from the resonance frequency and shape oscillation measurements (Eqs. 1 and 3). The predicted values were 74 mN/m for water (actual=72.9 mN/m) and 36 mN/m for the alcohol/water mixture (actual=27.4 mN/m). However, this method is applicable only if the liquid density is known. Without prior knowledge of the physical properties of the liquid, if the resonance frequency, shape oscillation frequency, and terminal velocity of the bubble are measured, and Eqs. (6)–(8) hereof employed, the liquid surface tension and density (and bubble size) can be determined. This is demonstrated for the case of water and a water-isopropanol mixture in TABLE 2. The calculated values agree well with measured values reported in the literature. The equation for terminal velocity, Eq. (3), applies for high Reynolds numbers (450<N R <1900), so accurate values for the other liquids were not obtained. A more general equation for terminal velocity may allow extraction of physical parameters for a wide range of liquids. However, by using smaller bubbles (N R <1), which obey Stokes' Law (See L.-S. Fan and K. Tsuchiya, supra), it should be possible to determine viscosity as well by simply measuring the bubble resonance frequency and the terminal velocity (see Eq. 9). TABLE 2 Observable Liquid Parameter Calculated Value Literature Value Water f n = 86.7 Hz ρ = 0.988 ± 0.039 g/cm 3 ρ = 1.00 g/cm 3 (c = 1.8) f 0 = 2273 Hz R 0 = 1.465 ± 0.038 mm N/A U 0 = 0.311 m/s σ = 77.0 ± 1.5 mN/m σ = 72.9 mN/m Isopropyl f n = 100.3 Hz ρ = 0.931 ± 0.13 g/cm 3 ρ = 0.940 g/cm 3 alcohol/ f 0 = 3249 Hz R 0 = 0.963 ± 0.08 mm N/A Water U 0 = 0.192 m/s σ = 36.0 ± 0.955 mN/m σ = 27.38 mN/m mixture (c = 1.0) The bubble resonance width also provides a quantitative measure of the viscosity. If the present apparatus is calibrated using a liquid having known viscosity, the resonance width can provide liquid viscosity information. The foregoing description of the invention has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.
An apparatus and method is described for measuring properties of bubbles from which certain physical characteristics of the liquid in which the bubbles are generated can be determined. The evolution of a bubble includes (1) formation and growth at a nozzle disposed within the liquid through which a gas is flowed, or formation and growth as a result of cavitation in the liquid from the application of focused acoustic energy to a location within the liquid; (2) detachment and resonance; and (3) rise towards terminal velocity. Measurements of the resonance frequency, the shape oscillation frequency and the terminal velocity of the bubble allow the determination of the density and surface tension of the liquid and the radius of the bubble. Since the properties of the liquid affect the evolution of the bubble, observation of a rising bubble can be used as a tool for characterizing the liquid; as an example, the present invention can be used to monitor changes in the liquid itself or changes in the concentration or integrity of materials dissolved in the liquid.
Provide a concise summary of the essential information conveyed in the given context.
[ "RELATED CASES The present application claims the benefit of Provisional Patent Application Ser.", "No. 60/442,281, for “Characterization of Liquids Using Gas Bubbles”", "filed on Jan. 24, 2003.", "FIELD OF THE INVENTION The present invention relates generally to characterization of liquids and, more particularly, to the determination of certain properties of a liquid by measuring characteristics of bubbles formed therein.", "BACKGROUND OF THE INVENTION The dynamics of gas bubbles in liquids has been studied using a variety of optical and acoustic techniques for industrial applications and for basic physics research.", "High-speed photography (See, e.g., T. G. Leighton, The Acoustic Bubble .", "(Academic Press, London, 1994), pp. 119–207;", "H. C. Pumphrey and A. J. Walton, “Experimental study of the sound emitted by water drops impacting on a water surface,” European Journal of Physics, 9(3), 225–231 (1988);", "and P. Di Marco et al.", ", “Experimental Study on Terminal Velocity of Nitrogen Bubbles”", "in FC-72, Proc.", "Experimental Heat Transfer, Fluid Mechanics and Thermodynamics 2001, ed.", "by G. P. Celata et al.", ", GR, Sep. 24–28, 2001, ETS, Pisa, pp. 1349–1359.) is the most widely used technique, but requires complex image processing to extract quantitative information about bubble behavior.", "Laser Doppler anemometry (See, e.g., R. Mahalingam et al.", ", “Velocity measurements in Two-Phase Bubble-Flow Regime with Laser-Doppler Anemometry,” J. Am.", "Inst.", "Chem.", "Eng.", "22, 1152–1155 (1976).) has been used to study bubble terminal velocity, and the laser-Schlieren (See, e.g., D. S. Hacker and F. D. Hussein, “The Application of a Laser-Schlieren Technique to the Study of Single Bubble Dynamics,” Ind.", "Eng.", "Chem.", "Fund.", "17(4), 277–283 (1978).) technique has been used to study bubble shape and terminal velocities.", "Optical interferometry (See, e.g., A. Gelmetti et al.", ", “An optical interferometer for gas bubble measurements,” Rev. Sci.", "Instrum.", "67(10), 3564–3566 (1996);", "and L. Rovati et al.", ", 64 (6), 1463–1467 (1993).) has found use in the study of bubble oscillations in a sound field.", "These optical techniques require both a transparent liquid and window access to the liquid through the container.", "Radio-frequency probes (See, e.g., N. Abuaf et al.", ", “Radio-frequency probe for bubble size and velocity measurements,” Rev. Sci.", "Instrum.", "50(10), 1260–1263 (1979).) have also been used to investigate bubble size and terminal velocity.", "Passive listening (See, e.g., T. G. Leighton and A. J. Walton, “An experimental study of the sound emitted from gas bubbles in a liquid”, Euro.", "J. Phys.", "8, 98–104 (1987).) at acoustic frequencies is typically used to study bubble resonance.", "Ultrasonic pulsed Doppler procedures have been used for bubble detection (See, e.g., R. Y. Nishi, “Ultrasonic detection of bubbles with Doppler flow transducers,” Ultrasonics, 10, 173–179 (1972).) and terminal velocity measurements (See, e.g., H. Kellerman et al.", ", “Dynamic modeling of gas-hold-up in different electrolyte systems,” J. Appl.", "Electrochem.", "28, 311–319 (1998).).", "Typically, the above-mentioned techniques are used to study only one or two aspects of the behavior of bubbles.", "There are three principal stages to the evolution of a gas bubble: (1) formation and growth at the tip of a nozzle located in a liquid;", "(2) detachment and resonance;", "and (3) ascent to terminal velocity.", "In the first stage of evolution, the bubble grows to a specific size at the opening of the nozzle, the radius of the nozzle opening and the properties of the surrounding liquid determining the ultimate size of the bubble (See, e.g. M. S. Longuet-Higgins, B. R. Kerman, and K. Lunde, “The release of air bubbles from an underwater nozzle,” J. Fluid Mech.", "230 (1991) p365–390.) As the bubble pinches off and detaches from the nozzle, it resonates (breathing-mode) briefly at a natural frequency determined primarily by its radius and the liquid density.", "The frequency f 0 of this resonance oscillation was first calculated by M. Minnaert in “On Musical Air-Bubbles and the Sounds of Running Water,” Phil.", "Mag.", "16, 235–248 (1933) to be: f 0 = 1 2 ⁢ π ⁢ ⁢ R 0 ⁢ 3 ⁢ γ ⁢ ⁢ p 0 ρ , ( 1 ) where R 0 is the radius of the bubble, γ is the ratio of specific heat at constant pressure to the specific heat at constant volume of the gas, ρ 0 is the hydrostatic pressure of surrounding liquid, and ρ is the liquid density.", "This equation is reasonably accurate for the mm-sized bubbles.", "For significantly smaller bubbles, Equ.", "1 must be modified to account for the effects of surface tension (See, T. G. Leighton, supra).", "The bubble resonance can be detected and quantified using a hollow cylindrical piezoelectric transducer surrounding the bubble.", "After detachment from the nozzle, the bubble accelerates to its terminal velocity which depends on the size of the bubble.", "For low viscosity fluids, such as water, the behavior of the rising bubble falls within several regions.", "Small bubbles (less than 0.035 cm radius) are spherical and rise substantially vertically at a speed determined by Stokes'", "Law.", "Larger bubbles (0.035 cm to 0.07 cm), have internal air circulation, which reduces shear stresses at the interface leading to a velocity higher than predicted by Stokes'", "Law.", "Between 0.07 cm and 0.3 cm, bubbles are elliptical and follow a spiral or zigzag path.", "Drag increases due to vortex formation in the bubble wake.", "Bubbles greater than 0.3 cm form spherical cap shapes (See, e.g., L.-S.", "Fan and K. Tsuchiya, Bubble Wake Dynamics in Liquids and Liquid - Solid Suspensions (Butterworth-Heinemann, Boston, 1990), pp. 36–43.).", "The terminal velocity U 0 depends on the buoyant and drag forces on the bubble (See, H. Kellerman et al.", ", supra): U 0 = 8 3 ⁢ gR 0 C D , ( 2 ) where g is the acceleration due to gravity, R 0 is the radius of the bubble and C D is the drag coefficient.", "The drag coefficient depends on physical properties of the liquid and the size of the bubble.", "A theory by G. Bozzano and M. Dente, “Shape and terminal velocity of single bubble motion: a novel approach,” Computers &", "Chemical Engineering.", "25 (2001) 571–576, is useful for calculating the drag coefficient because it covers a wide range of bubble sizes and liquid properties.", "The drag coefficient is calculated using Reynolds, Eotvos, and Morton numbers, which depend on the surface tension, density, and viscosity of the liquid and the bubble size.", "An equation for terminal velocity applicable for air bubbles between 0.07 cm and 0.3 cm is given by (See L.-S Fan and K. Tsuchiya, supra): U 0 = c ⁢ ⁢ σ R 0 ⁢ ⁢ ρ , ( 3 ) where c=1.8 for a single component liquid (c is between 1.0 and 1.4 for mixtures).", "The presence of contaminants (e.g., surfactants, suspended particles) has a significant effect on the rise of the bubble due to the Marangoni effect and the immobilization of the air-liquid interface (See, e.g., G. Liger-Belair et al.", ", “On the Velocity of Expanding Spherical Gas Bubbles Rising in Line in Supersaturated Hydroalcoholic Solutions: Application to Bubble Trains in Carbonated Beverages,” Langmuir 16, 1889–1895 (2000).).", "The path of the rising bubbles is largely determined by the Reynolds number, N R .", "For low Reynolds numbers (N R <130), the bubble travels substantially vertically.", "For higher Reynolds numbers (130<N R <400), the tip of the wake behind the bubble becomes unstable and oscillates at a low frequency, leading to a zigzag path.", "For even higher Reynolds numbers (400<Re<350,000), vortices are periodically shed from alternate sides of the bubble on a plane that slowly revolves around the bubble, leading to a spiral path (See T. G. Leighton, supra).", "As the mm-sized bubble rises, it also undergoes shape oscillations (P.", "Di Marco et al.", ", supra).", "The frequency of these oscillations (See T. G. Leighton, supra) is given by: f n = 1 2 ⁢ π ⁢ ( n - 1 ) ⁢ ( n + 1 ) ⁢ ( n + 2 ) ⁢ σ ρ ⁢ ⁢ R 0 3 , ( 4 ) where f n is the frequency of oscillations, n is the mode number, and σ is the surface tension.", "Both terminal velocity and shape oscillations can be monitored by observing the Doppler frequency shift of sound reflected from the bubble.", "The speed, U, of the bubble is related to the speed of sound, the frequency of the sound source used to interrogate the bubble, and the frequency received by the detector utilized for the measurement according to: U = v ⁢ ( f r - f s ) ( f r + f s ) , ( 5 ) where ν is the liquid sound speed, f r is the received frequency, and f s is the source frequency (See, e.g., D. G. H. Andrews, “An experiment to demonstrate the principles and processes involved in medical Doppler ultrasound,” Phys.", "Educ.", "35(5), 350–353 (2000)).", "Accordingly, it is an object of the present invention to provide an apparatus and method for measuring liquid characteristics from the properties of bubbles formed therein.", "Additional objects, advantages and novel features of the invention will be set forth, in part, in the description that follows, and, in part, will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention.", "The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.", "SUMMARY OF THE INVENTION To achieve the foregoing and other objects, and in accordance with its purposes of the present invention, as embodied and broadly described herein, the method for measuring liquid properties hereof includes: forming a bubble in the liquid;", "measuring the resonance frequency of the bubble;", "measuring the shape oscillation frequency of the bubble;", "and measuring the terminal velocity of the bubble in the liquid.", "In another aspect of the invention and in accordance with its objects and purposes, the apparatus for measuring liquid properties hereof includes: means for forming a bubble in the liquid;", "means for measuring the resonance frequency of the bubble;", "means for measuring the shape oscillation frequency of the bubble;", "and means for measuring the terminal velocity of the bubble in the liquid.", "Benefits and advantages of the present invention include, but are not limited to, the noninvasive, inexpensive measurement of liquid density, surface tension and viscosity, and the monitoring of changes in these quantities.", "It should be mentioned that the invention is applicable to opaque liquids.", "Moreover, by making simultaneous passive listening and active Doppler measurements on a bubble, all aspects of the bubble evolution (bubble formation, growth, detachment and resonance, shape oscillations, terminal velocity, and rise path) can be observed which permits liquid properties to be determined.", "BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and form a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the invention.", "In the drawings: FIG. 1 is a schematic representation of the resonance-Doppler apparatus of the present invention showing a pump for injecting a gas into a chamber through a syringe needle, thereby producing a bubble;", "a cylindrical transducer disposed around the tip of the needle for detecting the sound generated both when the bubble forms and when it detaches;", "a Doppler probe disposed above the needle for monitoring the growth and rise of the bubble (T=transmitter, R=receiver);", "and a computer for analyzing the digitized output of both of these sensors.", "FIG. 2 is a schematic representation of an embodiment of the Doppler probe measurement electronics used in cooperation with the present resonance-Doppler apparatus, showing a local oscillator for exciting the transmitter of the Doppler probe at 10 MHz;", "an amplifier for amplifying the signal produced by the Doppler probe in response to the reflected sound from the rising bubble;", "a high-pass filter for reducing noise, the output therefrom being mixed with the local oscillator signal to produce sum and difference frequencies;", "and a low-pass filter for removing the sum frequency, leaving the difference, or Doppler, frequency.", "FIG. 3 is a schematic representation of a noninvasive embodiment of the resonance-Doppler apparatus of the present invention showing a piezoelectric ring (section) transducer disposed externally to a pipe or container bearing the liquid for generating focused, high intensity sound coaxially with the pipe and having sufficient intensity to generate bubbles, one at a time, by a cavitation process in the liquid;", "a function generator for producing tone bursts of sine-waves having a frequency matching the thickness mode resonance of the wall of the container;", "and an externally located Doppler probe for measuring the rate of ascent of the bubbles formed.", "FIG. 4 a illustrates signals detected during the evolution of a bubble, the black line representing the initial resonance signal detected by the cylindrical transducer, and the grey line representing the signal from the Doppler probe, the bubble forming at the tip of the needle at t 1 , growing until t 2 when it detaches from the needle, rising and ultimately reaching terminal velocity;", "and FIG. 4 b shows the bubble velocity as a function of time.", "FIG. 5 a shows the Fourier transform of a bubble resonance signal for two different water heights;", "and FIG. 5 b shows the bubble velocity as a function of time for the two heights.", "FIG. 6 is a long pathlength Doppler measurement for a single bubble rising in a spiral path.", "FIG. 7 a are Fourier transforms of bubble resonance signals for two air flows;", "while FIG. 7 b shows the bubble velocity as a function of time for the two flow rates of FIG. 7 a hereof.", "FIG. 8 a are Fourier transforms of bubble resonance signals when a surfactant is added to water compared with those for pure water;", "while FIG. 8 b shows the bubble velocity as a function of time for the two liquids.", "FIG. 9 a are Fourier transform of bubble resonance signals resulting when isopropyl alcohol is added to water, compared with those for pure water;", "while FIG. 9 b shows the bubble velocity as a function of time for the two liquids.", "FIG. 10 a are Fourier transforms of bubble resonance signals when particles are suspended in water compared with those for pure water;", "while FIG. 10 b shows the bubble velocity as a function of time for the two liquids.", "DETAILED DESCRIPTION Briefly, the present invention includes a method for determining surface tension, density and viscosity of a liquid, and for monitoring changes in these characteristics by measuring the resonance frequency, terminal velocity and shape oscillation frequency for bubbles formed in the liquid under investigation.", "Bubbles are formed in the liquid using forced air flow from a syringe tip;", "however, it is anticipated that a cavitation process in the liquid induced by the application of ultrasound to the liquid can be used as well.", "Additionally, other gases can be employed to form bubbles in situations where the liquid is sensitive to oxygen.", "From Eq.", "1 hereinabove, it is seen that the resonance frequency of a bubble is related to γ which is the ratio of the specific heat of the gas at constant pressure to the specific heat thereof at constant volume, the value of which depends on the nature of the gas.", "For example, for monotomic gases, γ=1.67, for diatomic gases, γ=1.41, while for polyatomic gases γ=1.3.", "Therefore, the resonant frequency of the bubble will depend on the gas being used for its generation.", "The terminal velocity and the shape oscillation frequency for the bubble are not affected by the choice of gas.", "Typically, when bubbles are generated using cavitation, the vapor inside the bubble will be the vapor of the liquid that is cavitating.", "However, if gas is dissolved in the liquid, a portion of this gas may enter the bubble.", "In fact, dissolved gases lower the threshold for cavitation.", "Additionally, under certain circumstances the identity of the dissolved gas can be determined from the resonance frequency.", "As long as a consistent set of bubble measurements is used in the analysis in accordance with the present invention;", "that is, measurements taken using either the cavitation method or the syringe method for bubble formation, the above-mentioned properties of the liquid can be determined.", "Although analytic algorithms are provided hereinbelow for extracting or monitoring the desired characteristics of the liquid from the three measured quantities, more general versions of Equations 1–4 can be parametrically solved numerically to extract these characteristics.", "The present method is not restricted to optically transparent liquids, and the quantities can be measured using technology found in references listed hereinabove.", "One embodiment of the invention includes: (1) passive listening using acoustic technology to measure bubble resonance frequency;", "and (2) an active Doppler (Joint Time-Frequency Analysis) method to measure bubble terminal velocity and shape oscillation frequency.", "Since these quantities are affected by the physical properties of the surrounding liquid (that is, surface tension, density, viscosity), the liquid can be characterized and monitored from measurements on bubbles formed therein.", "Equations (1)–(4) show the relationship of bubble resonance frequency, terminal velocity, and shape oscillation frequency to the surface tension and density of the host liquid.", "Rearranging these equations, the above physical properties of the liquid determined from observable quantities are as follows: ρ = 0.350 ⁢ cf n 2 ⁢ p 0 f 0 2 ⁢ U 0 2 ( 6 ) R 0 = 0.551 ⁢ U 0 f s ⁢ c ( 7 ) σ = 0.193 ⁢ f n ⁢ U 0 ⁢ p 0 f 0 2 ⁢ c ( 8 ) For small bubbles, where Stokes'", "Law applies, the viscosity is inversely proportional to terminal velocity.", "Therefore, the viscosity of the liquid can also be determined from the terminal velocity, once the system is calibrated using a liquid having known viscosity (Calibration may not be necessary since viscosity can be determined from bubble resonance frequency and terminal velocity.", "Liquid viscosity η is inversely proportional to the product of square of the resonance frequency and the terminal velocity as η∝1/(f 0 2 U 0 )).", "The viscosity and the resonance frequency are the two measured parameters.", "Equation 9 below provides a more quantitative relationship among the measured parameters in order to experimentally determine viscosity η = 0.0236 ⁢ gp 0 f 0 2 ⁢ U 0 .", "( 9 ) The parameters g, p 0 , f 0 , and U 0 are defined hereinabove.", "The dynamics of bubble rise through any liquid is a function of bubble size which in turn depends on liquid properties such as density and surface tension.", "Equations (6)–(8) faithfully represent the behavior of bubbles having a range of sizes below a cut-off value.", "To provide a bubble size for comparison among various liquids, a dimensionless number called the Eotvos number is used.", "The Eotvos number takes into account liquid density and surface tension to normalize the bubble size.", "Although the above equations (which are used principally because of their simplicity of form) are strictly valid for liquids having an Eotvos number ≦50, a large range of bubble sizes can be accommodated by numerically solving more general equations.", "The method of the present invention is expected to be useful for Eotvos numbers ≦50.", "For water, this condition defines a bubble having a radius of approximately 7 mm.", "Reference will now be made in detail to the present preferred embodiments of the invention examples of which are illustrated in the accompanying drawings.", "In what follows, identical callouts will be used for similar or identical structure.", "Turning now to FIG. 1 , hereof, a schematic representation of the apparatus, 10 , used to demonstrate the present method is shown.", "In this embodiment of the invention, bubbles are generated by forcing air from air pump, 12 , through metal syringe, 14 .", "The flow-rate was adjustable both using valve, 16 , and by changing the air pressure delivered by the pump.", "The syringe needle was inserted through the closed bottom portion of a vertically oriented plastic tube, 18 , which served as the container for the liquids, 20 , investigated.", "The tube was generally filled to 6 cm above the syringe needle, and measurements were made using water nominally at 20° C., the ambient room temperature.", "Clearly, bubbles can be formed using other gases, and the present apparatus can be used to investigate the associated liquid.", "The size of the orifice of the syringe is unimportant.", "Although the initial size of the bubble changes with orifice size, and the measured properties scale with the bubble size, so long as the bubble size is consistent with the discussion of the Eotvos number, hereinabove (as an example, for water, the bubble diameter should be less than about 7 mm), the liquid parameters derived from these measured properties are unaffected.", "Hollow cylindrical piezoelectric transducer (2.55-cm long, 2.30-cm inner diameter, 1.20-mm thick, Boston Piezo-Optics, Mass.), 22 , was disposed symmetrically around the tip of the syringe to enable detection of sound produced by bubble, 24 , in many directions.", "Traditionally, such resonance measurements are made from one side using a hydrophone.", "The transducer output was amplified using amplifier, 26 .", "A frequency-mixing-based Doppler apparatus which includes Doppler probe, 28 , controlled by Doppler circuitry, 30 , was used to monitor the speed of ascending bubble 24 as a function of time.", "The outputs of both the cylindrical transducer and circuitry 30 were directed to a 2-channel, digital storage oscilloscope (DSO), 32 , which digitized the data and transferred it to computer, 34 , for analysis.", "Doppler circuitry 30 is schematically described in FIG. 2 hereof.", "Function generator, 36 , provides ultrasonic excitation for transmitter, 38 , of dual-element Doppler probe (9.4 MHz, 10-cm long, 9.5-mm diameter, Parks Medical Pencil Probe), 28 , normally placed about 4 cm above the tip of syringe 14 .", "Receiver, 40 , of the Doppler probe 28 detects the sound reflected from ascending bubble 24 .", "Amplifier, 42 , and high-pass filter, 44 , are used to process the signal received by receiver 40 before it is mixed with the signal input to transmitter 38 using mixer, 46 , to produce sum and difference frequencies.", "Low-pass filter, 48 , permits the Doppler difference frequency to be obtained from the mixer.", "It is this difference frequency that is related to the bubble velocity and shape oscillations as will be discussed hereinbelow.", "Doppler probe 28 is shown in FIG. 1 hereof to include a pair of tilted transducers which are angled downwards ( 38 , 40 ) to monitor the ascent of the bubbles;", "the probe utilized was a commercially available medical Doppler transducer probe designed for viewing veins under close-focusing conditions.", "FIG. 3 hereof is a schematic representation of a noninvasive embodiment of the resonance-Doppler method of the present invention.", "In this embodiment, both the bubble generation and bubble detection are achieved externally to the pipe or cylindrical container bearing the liquid under investigation.", "Piezoelectric ring transducer, 50 , which can either be a complete ring or two half-rings that are in electrical connection is used to generate high intensity sound at the center and on the axis of the pipe.", "The curvature of the container focuses sound at the axis of the container.", "Function generator, 52 , produces tone bursts of sine-waves having a frequency that matches the thickness mode resonance of the wall of the container.", "Frequency matching permits the sound to be transmitted through the wall with the maximum efficiency.", "The frequency used can be either at the fundamental frequency or higher harmonics of the wall thickness mode resonance frequency.", "A broad range of acoustic frequencies can be used, but sound transmission through the wall may vary.", "The burst frequency, duration, and duty cycle can be adjusted for a chosen bubble generation rate.", "The output of the function generator is amplified by power amplifier, 54 , before being applied to the transducer.", "By adjusting the power, frequency, burst duration, and duty cycle it is also possible to create a single bubble in the liquid inside the pipe or container by the cavitation process (See, e.g., T. G. Leighton, The Acoustic Bubble (Academic Press, London, 1994), 504–506).", "Passive or active circuit directional coupler, 56 , allows the same transducer to be used for both generating bubbles by cavitation, and for detecting the bubble resonance.", "The bubble resonance signal detected by cavitation transducer 50 is amplified by signal amplifier, 58 , before being directed to multiplexer, 60 , and digitized using A/D converter, 62 .", "The resonance signal is generated when the burst signal is off.", "Microcontroller, 64 controls function generator 52 and multiplexer 60 as well as processing the signals received from both Doppler probe 28 and cavitation transducer 50 .", "The tilt of elements 38 and 40 of Doppler probe 28 shown in FIG. 1 , hereof is not a requirement of the present invention;", "rather, a flat-surfaced, concentric transducer head having an outer ring surrounding an inner disk, where one transducer serves as the transmitter and the other as a receiver, will provide a symmetric sound beam pattern without focusing.", "This permits a longer viewing range for the bubble;", "that is, the received signal has been observed by the present inventor to be strong along the entire path of the bubble instead of only in the focused beam intersection region of the two tilted transducers.", "The transducers for noninvasive measurements are acoustically coupled to the wall (a coupling medium can be employed to improve the acoustic coupling), and the resulting sound waves are directed (refracted) at an angle into the liquid inside.", "The Doppler probe frequency can be chosen to match a higher harmonic of the wall resonance frequency, allowing maximum sound transmission.", "The Doppler frequency is chosen to be greater than 5 MHz and, more typically, it is above 10 MHz.", "The received signal from the cavitation transducer, and the amplified output from mixer/amplifier/filter, 66 , are directed through multiplexer 60 to A/D converter 62 before entering microcontroller 64 for signal processing.", "The microcontroller is capable of performing rapid Fast Fourier Transform (FFT) and Short-Time Fourier Transform (STFT) calculations using the bubble resonance signal and the Doppler signal as will be described in more detail hereinbelow.", "The bubble resonance signal from the cylindrical transducer (as shown in FIG. 1 hereof) was transformed using FFT to obtain the frequency spectrum of the resonance of the bubble.", "The Doppler signal, by contrast, was analyzed using Joint Time-Frequency Analysis (JTFA), which is a technique in which the frequency components of a signal are displayed as a function of time.", "As result, signal changes, such as a time-dependent Doppler frequency, can be observed, thereby permitting the speed of the bubble to be determined as a function of time during the period of growth and rise.", "JTFA was performed using either the Short-Time Fourier Transform method (STFT) or the Continuous Wavelet Transform (CWT) procedure (See, e.g., S. Qian and D. Chen, Joint Time-Frequency Analysis .", "(Prentice Hall PTR, Upper Saddle River, 1996), pp. 45–52), both of which gave the same time-dependent velocity information.", "Measurements were made at various temperatures, airflow rates, liquid heights, and transducer positions.", "Water temperature was measured using a digital thermometer with a 0.1° C. resolution.", "The effect of liquid height was evaluated by changing the amount of liquid in the container.", "Doppler measurements were performed at various probe heights above the syringe (See FIG. 1 hereof).", "A height of ˜2.5 cm was used to study bubble formation, whereas a height of ˜10 cm was used to study the ascent path of the bubble.", "The effect of liquid contaminants was also examined.", "To determine the effects of surfactant contaminants, a 1% solution (by volume) of dishwashing soap in water was used.", "Solutions of isopropyl alcohol and water at various concentrations (with the highest concentration being 66% water, 34% alcohol by volume) were used to investigate the effect of organic chemical contaminants on the bubbles.", "A dilute suspension (˜1 g/L) of turmeric particles (10 to 100 μm, having irregular shapes) in water was used to investigate the effect of suspended particles on bubble behavior.", "Turmeric was chosen because it provided a stable suspension.", "Turning now to the measurements made in accordance with the present invention, FIG. 4 a shows the signals from the cylindrical transducer and Doppler probe, whereas FIG. 4 b shows the STFT of the Doppler signal, expressed as bubble velocity, which is proportional to the measured frequency difference.", "The measurement was made with the Doppler probe located 2.5 cm above the syringe.", "At time t 1 , a small spike in the resonance signal (cylindrical transducer output) was observed, which is most likely due to a meniscus forming at the tip of the syringe ( FIG. 4 a ).", "From time t 1 to time t 2 , the bubble enlarged on the tip of the syringe.", "The growth process commenced with a rapid expansion of the bubble upward followed by horizontal growth.", "This was observed in the Doppler signal as an initial speed of 0.1 m/s at t 1 which decreased to 0.05 m/s.", "At t 2 the bubble detaches and begins to resonate, as indicated by a rapid increase in the speed (higher frequency Doppler signal) and an associated burst in the resonance signal.", "After t 2 the bubble accelerated to its terminal velocity while undergoing shape oscillations as observed by the oscillations in the STFT signal in FIG. 4 b .", "The shape oscillation frequency has been observed to remain constant over time unless the properties of the liquid change with height;", "for example, if the liquid is stratified it may have a density gradient which varies as a function of height.", "In this situation, one would observe a variation in the shape oscillation frequency and the terminal velocity of the bubble.", "With the exclusion of FIG. 6 , the graphs labeled with (a) in the following figures show FFTs of the signal from the cylindrical transducer, whereas the graphs labeled with (b) show STFTs of the Doppler signal.", "The STFT is shown as a two-dimensional plot of velocity over time, with the degree of darkness indicating the magnitude of the Doppler signal.", "The Resonance-Doppler measurements in the narrow temperature range studied (between 0° C. and 8° C.), show only a small effect of temperature on the bubble behavior (i.e., formation, growth, resonance, and rise).", "FIG. 5 shows that an increase in water height decreases the bubbling rate and the width of the resonance.", "These changes are due to the differences in the hydrostatic pressure.", "As stated, the two transducers of the medical Doppler probe employed were slightly angled towards each other, which resulted in a focused beam directed below the probe (T and R in FIG. 1 ).", "Therefore, the probe detects the ascending bubble in a region directly below it.", "When the probe was positioned close to the tip of the syringe (e.g., about 4 cm), only the formation of the bubble and the start of its ascent can be adequately observed.", "When the probe at was located at approximately 10 cm, later periods of the ascent were found to be observable, including the nature of the rise path (e.g., straight, zigzag, or spiral).", "FIG. 6 shows how a spiral ascent path of the bubble affects the STFT data.", "For example, the oscillations in the velocity and the variations in the amplitude of the STFT of the Doppler signal (darkness of the plot) are due to the bubble moving in and out of the beam of the Doppler probe.", "A flat, concentric arrangement of the transducer elements having greater beam spread was also used, allowing more of the bubble's ascent to be observed (See FIG. 6 hereof).", "As the flow rate of air increases, the bubble size remains relatively constant, as indicated by the fact that the resonance frequency does not change.", "At greater airflow rates, the bubble resonance is larger in amplitude ( FIG. 7 a ), probably due a stronger axial jet from a faster detachment from the nozzle (See T. G. Leighton and A. J. Walton, supra).", "Moreover, the number of bubbles released per second increases, as is observed by the increased number of bubble detachments in a given length of time ( FIG. 7 b ).", "The presence of surfactant was found to have a pronounced effect on many aspects of the evolution of the bubbles.", "For example, the bubble resonance moves to a higher frequency and becomes more damped ( FIG. 8 a ).", "The increase in the resonance frequency is due to the smaller size of the bubbles (see Eq.", "1).", "The bubbles are smaller in the soap solution than in plain water since they detach sooner because of the lower surface tension.", "Other effects include the following: the terminal velocity was less than half of the terminal velocity in pure water, the bubbling rate increased by greater than a factor of two, and the shape oscillations became too small to be easily determined ( FIG. 8 b ).", "These observations are likely due to the presence of surfactant molecules at the air-liquid interface.", "The increase in resonance peak width is likely due to the higher viscosity of the soap solution.", "Other contaminants, such as alcohol, also have a substantial change on the bubble's evolution.", "For example, the presence of isopropyl alcohol shifts the resonance peak to a higher frequency and increases the damping ( FIG. 9 a ).", "In addition, the terminal velocity is significantly reduced, the bubbling rate increases, and the shape oscillations becomes smaller ( FIG. 9 b ).", "The period of bubble growth is also shorter, showing that the bubbles detach from the nozzle sooner.", "These effects are very similar to those observed with the surfactant.", "This is likely due to the fact that both alcohol and soap lower the surface tension of the water, and the higher viscosity of the isopropyl alcohol concentration leads to a wider resonance peak width.", "FIG. 10 shows the effect of suspended particles (turmeric), in water.", "The suspended particles have little observable effect on the resonance of the bubble ( FIG. 10 a );", "however, the rise is affected.", "Instead of traveling along a wide spiral path upwards, as in the case of uncontaminated water, it was observed that the bubbles follow a tight spiral around the axis of the cylindrical test chamber.", "Moreover, the shape oscillations decay rapidly becoming too small to measure.", "These changes likely occur because the suspended particles adhere to the air-water interface of the bubble, thereby stiffening the boundary and increasing the effective viscosity (See L.-S.", "Fan and K. Tsuchiya, supra) TABLE 1 summarizes the experimental results of various aspects of bubble dynamics and compares some of the results with theoretical predictions.", "TABLE 1 Bubble Shape Terminal Bubbling Radius oscillation velocity rate (mm) Freq.", "(Hz) (m/s) (bub.", "/s) Water (Exp.) 1.44 ± 0.05 86.7 ± 5.5 0.311 ± 0.009 ~2 (Theor.", "Pred.) 1.23 92.6 0.295 — Alcohol (Exp.) 1.05 ± 0.02 100 ± 9.5 0.192 ± 0.008 ~4 (Theor.", "Pred.) 1.00 104 0.228 N/A Soap (Exp.) 1.12 ± 0.09 None 0.190 ± 0.006 ~6 Turmeric 1.42 ± 0.07 None 0.248 ± 0.051 ~2 (Exp.) Equation 1 is used to calculate the experimental bubble size from its resonance frequency.", "For theoretical predictions of bubble size, see e.g., M. S. Longuet-Higgins et al.", ", supra, which describes bubble formation at low flow rates.", "This is not the situation for the present measurements, which may be the cause for the observed differences between the theoretical and the measured bubble sizes.", "The frequency of the shape oscillations in the time-frequency plots is determined by averaging the period of four oscillations and taking the reciprocal.", "The theoretical frequencies (Eq.", "3) are determined for a second-order (n=2, ellipsoidal) oscillation and agree well with experimental values for water and the alcohol/water mixture.", "The alcohol/water mixture shows a higher shape oscillation frequency because of the smaller bubble radius as compared with plain water.", "No shape oscillations could be easily discerned with the other contaminants.", "The theory by G. Bozanno and M. Dente, supra, was used to determine the drag coefficient from the terminal velocity, which is in turn used in Eq.", "(2).", "The decrease in the terminal velocity of the isopropyl alcohol/water mixture is consistent with theory (smaller bubble radius).", "Thus, by measuring the evolution of the bubble (bubble resonance, terminal velocity, and shape oscillations), certain physical properties of the liquid can be measured and monitored.", "For example, surface tension can be determined from the bubble radius, which is in turn derived from the resonance frequency and shape oscillation measurements (Eqs.", "1 and 3).", "The predicted values were 74 mN/m for water (actual=72.9 mN/m) and 36 mN/m for the alcohol/water mixture (actual=27.4 mN/m).", "However, this method is applicable only if the liquid density is known.", "Without prior knowledge of the physical properties of the liquid, if the resonance frequency, shape oscillation frequency, and terminal velocity of the bubble are measured, and Eqs.", "(6)–(8) hereof employed, the liquid surface tension and density (and bubble size) can be determined.", "This is demonstrated for the case of water and a water-isopropanol mixture in TABLE 2.", "The calculated values agree well with measured values reported in the literature.", "The equation for terminal velocity, Eq.", "(3), applies for high Reynolds numbers (450<N R <1900), so accurate values for the other liquids were not obtained.", "A more general equation for terminal velocity may allow extraction of physical parameters for a wide range of liquids.", "However, by using smaller bubbles (N R <1), which obey Stokes'", "Law (See L.-S.", "Fan and K. Tsuchiya, supra), it should be possible to determine viscosity as well by simply measuring the bubble resonance frequency and the terminal velocity (see Eq.", "9).", "TABLE 2 Observable Liquid Parameter Calculated Value Literature Value Water f n = 86.7 Hz ρ = 0.988 ± 0.039 g/cm 3 ρ = 1.00 g/cm 3 (c = 1.8) f 0 = 2273 Hz R 0 = 1.465 ± 0.038 mm N/A U 0 = 0.311 m/s σ = 77.0 ± 1.5 mN/m σ = 72.9 mN/m Isopropyl f n = 100.3 Hz ρ = 0.931 ± 0.13 g/cm 3 ρ = 0.940 g/cm 3 alcohol/ f 0 = 3249 Hz R 0 = 0.963 ± 0.08 mm N/A Water U 0 = 0.192 m/s σ = 36.0 ± 0.955 mN/m σ = 27.38 mN/m mixture (c = 1.0) The bubble resonance width also provides a quantitative measure of the viscosity.", "If the present apparatus is calibrated using a liquid having known viscosity, the resonance width can provide liquid viscosity information.", "The foregoing description of the invention has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching.", "The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.", "It is intended that the scope of the invention be defined by the claims appended hereto." ]
CROSS-REFERENCE TO RELATED APPLICATIONS Priority of U.S. Provisional Patent Application Ser. No. 60/409,177, filed Sep. 9, 2002, incorporated herein by reference, is hereby claimed. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not applicable REFERENCE TO A “MICROFICHE APPENDIX” Not applicable BACKGROUND In top drive rigs, the use of a top drive unit, or top drive power unit is employed to rotate drill pipe, or well string in a well bore. Top drive rigs can include spaced guide rails and a drive frame movable along the guide rails and guiding the top drive power unit. The travelling block supports the drive frame through a hook and swivel, and the driving block is used to lower or raise the drive frame along the guide rails. For rotating the drill or well string, the top drive power unit includes a motor connected by gear means with a rotatable member both of which are supported by the drive frame. During drilling operations, when it is desired to “trip” the drill pipe or well string into or out of the well bore, the drive frame can be lowered or raised. Additionally, during servicing operations, the drill string can be moved longitudinally into or out of the well bore. The stem of the swivel communicates with the upper end of the rotatable member of the power unit in a manner well known to those skilled in the art for supplying fluid, such as a drilling fluid or mud, through the top drive unit and into the drill or work string. The swivel allows drilling fluid to pass through and be supplied to the drill or well string connected to the lower end of the rotatable member of the top drive power unit as the drill string is rotated and/or moved up and down. Top drive rigs also can include elevators are secured to and suspended from the frame, the elevators being employed when it is desired to lower joints of drill string into the well bore, or remove such joints from the well bore. At various times top drive operations, beyond drilling fluid, require various substances to be pumped downhole, such as cement, chemicals, epoxy resins, or the like. In many cases it is desirable to supply such substances at the same time as the top drive unit is rotating and/or moving the drill or well string up and/or down, but bypassing the top drive's power unit so that the substances do not damage/impair the unit. Additionally, it is desirable to supply such substances without interfering with and/or intermittently stopping longitudinal and/or rotational movement by the top drive unit of the drill or well string. A need exists for a device facilitating insertion of various substances downhole through the drill or well string, bypassing the top drive unit, while at the same time allowing the top drive unit to rotate and/or move the drill or well string. One example includes cementing a string of well bore casing. In some casing operations it is considered good practice to rotate the string of casing when it is being cemented in the wellbore. Such rotation is believed to facilitate better cement distribution and spread inside the annular space between the casing's exterior and interior of the well bore. In such operations the top drive unit can be used to both support and continuously rotate/intermittently reciprocate the string of casing while cement is pumped down the string's interior. During this time it is desirable to by-pass the top drive unit to avoid possible damage to any of its portions or components. The following U.S. patents are incorporated herein by reference: U.S. Pat. No. 4,722,389. While certain novel features of this invention shown and described below are pointed out in the annexed claims, the invention is not intended to be limited to the details specified, since a person of ordinary skill in the relevant art will understand that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation may be made without departing in any way from the spirit of the present invention. No feature of the invention is critical or essential unless it is expressly stated as being “critical” or “essential.” BRIEF SUMMARY The apparatus of the present invention solves the problems confronted in the art in a simple and straightforward manner. The invention herein broadly relates to an assembly having a top drive arrangement for rotating and longitudinally moving a drill or well string. In one embodiment the present invention includes a swivel apparatus, the swivel generally comprising a mandrel and a sleeve, the swivel being especially useful for top drive rigs. The sleeve can be rotatably and sealably connected to the mandrel. The swivel can be incorporated into a drill or well string and enabling string sections both above and below the sleeve to be rotated in relation to the sleeve. Additionally, the swivel provides a flow path between the exterior of the sleeve and interior of the mandrel while the drill string is being moved in a longitudinal direction (up or down) and/or being rotated/reciprocated. The interior of the mandrel can be fluidly connected to the longitudinal bore of casing or drill string thus providing a path from the sleeve to the interior of the casing/drill string. In one embodiment an object of the present invention is to provide a method and apparatus for servicing a well wherein a swivel is connected to and below a top drive unit for conveying pumpable substances from an external supply through the swivel for discharge into the well string, but bypassing the top drive unit. In another embodiment of the present invention is provided a method of conducting servicing operations in a well bore, such as cementing, comprising the steps of moving a top drive unit longitudinally and/or rotationally to provide longitudinal movement and/or rotation/reciprocation in the well bore of a well string suspended from the top drive unit, rotating the drill or well string and supplying a pumpable substance to the well bore in which the drill or well string is manipulated by introducing the pumpable substance at a point below the top drive power unit and into the well string. In other embodiments of the present invention a swivel placed below the top drive unit can be used to perform jobs such as spotting pills, squeeze work, open formation integrity work, kill jobs, fishing tool operations with high pressure pumps, sub-sea stack testing, rotation of casing during side tracking, and gravel pack or frack jobs. In still other embodiments a top drive swivel can be used in a method of pumping loss circulation material (LCM) into a well to plug/seal areas of downhole fluid loss to the formation and in high speed milling jobs using cutting tools to address down hole obstructions. In other embodiments the top drive swivel can be used with free point indicators and shot string or cord to free stuck pipe where pumpable substances are pumped downhole at the same time the downhole string/pipe/free point indicator is being rotated and/or-reciprocated. In still other embodiments the top drive swivel can be used for setting hook wall packers and washing sand. In still other embodiments the top drive swivel can be used for pumping pumpable substances downhole when repairs/servicing is being done to the top drive unit and rotation of the downhole drill string is being accomplished by the rotary table. Such use for rotation and pumping can prevent sticking/seizing of the drill string downhole. In this application safety valves, such as TIW valves, can be placed above and below the top drive swivel to enable routing of fluid flow and to ensure well control. The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: FIG. 1 is a schematic view showing a top drive rig with one embodiment of a top drive swivel incorporated in the drill string; FIG. 2 is a schematic view of one embodiment of a top drive swivel; FIG. 3 is a sectional view of a mandrel which can be incorporated in the top drive swivel of FIG. 2 ; FIG. 4 is a sectional view of a sleeve which can be incorporated into the top drive swivel of FIG. 2 ; FIG. 5 is a right hand side view of the sleeve of FIG. 4 ; FIG. 6 is a sectional view of the top drive swivel of FIG. 2 ; FIG. 6A is a sectional view of the packing unit shown in FIG. 6 ; FIG. 6B is a top view of the packing injection ring shown in FIGS. 6 and 6A ; FIG. 6C is a side view section of the packing injection ring shown in FIG. 6B ; FIG. 7 is a top view of a clamp which can be incorporated into the top drive swivel of FIG. 2 ; FIG. 8 is a side view of the clamp of FIG. 7 ; FIG. 9 is a perspective view and partial sectional view of the top drive swivel shown in FIG. 2 . DETAILED DESCRIPTION Detailed descriptions of one or more preferred embodiments are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in any appropriate system, structure or manner. FIG. 1 is a schematic view showing a top drive rig 1 with one embodiment of a top drive swivel 30 incorporated into drill string 20 . FIG. 1 is shows a rig 1 having a top drive unit 10 . Rig 5 comprises-supports 16 , 17 ; crown block 2 ; traveling block 4 ; and hook 5 . Draw works 11 uses cable 12 to move up and down traveling block 4 , top drive unit 10 , and drill string 20 . Traveling block 4 supports top drive unit 10 . Top drive unit 10 supports drill string 20 . During drilling operations, top drive unit 10 can be used to rotate drill string 20 which enters wellbore 14 . Top drive unit 10 can ride along guide rails 15 as unit 10 is moved up and down. Guide rails 15 prevent top drive unit 10 itself from rotating as top drive unit 10 rotates drill string 20 . During drilling operations drilling fluid can be supplied downhole through drilling fluid line 8 and gooseneck 6 . At various times top drive operations, beyond drilling fluid, require substances to be pumped downhole, such as cement, chemicals, epoxy resins, or the like. In many cases it is desirable to supply such substances at the same time as top drive unit 10 is rotating and/or moving drill or well string 20 up and/or down and bypassing top drive unit 10 so that the substances do not damage/impair top drive unit 10 . Additionally, it is desirable to supply such substances without interfering with and/or intermittently stopping longitudinal and/or rotational movements of drill or well string 20 being moved/rotated by top drive unit 10 . This can be accomplished by using top drive swivel 30 . Top drive swivel 30 can be installed between top drive unit 10 and drill string 20 . One or more joints of drill pipe 18 can be placed between top drive unit 10 and swivel 30 . Additionally, a valve can be placed between top drive swivel 30 and top drive unit 10 . Pumpable substances can be pumped through hose 31 , swivel 30 , and into the interior of drill string 20 thereby bypassing top drive unit 10 . Top drive swivel 30 is preferably sized to be connected to drill string 20 such as 4½ inch IF API drill pipe or the size of the drill pipe to which swivel 30 is connected to. However, cross-over subs can also be used between top drive swivel 30 and connections to drill string 20 . FIG. 2 is a schematic view of one embodiment of a top drive swivel 30 . Top drive swivel 30 can be comprised of mandrel 40 and sleeve 150 . Sleeve 150 is rotatably and sealably connected to mandrel 30 . Accordingly, when mandrel 40 is rotated, sleeve 150 can remain stationary to an observer insofar as rotation is concerned. As will be discussed later inlet 200 of sleeve 150 is and remains fluidly connected to a the central longitudinal passage 90 of mandrel 40 . Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 . FIG. 3 is a sectional view of mandrel 40 which can be incorporated in the top drive swivel 30 . Mandrel 40 is comprised of upper end 50 and lower end 60 . Central longitudinal passage 90 extends from upper end 50 through lower end 60 . Lower end 60 can include a pin connection or any other conventional connection. Upper end 50 can include box connection 70 or any other conventional connection. Mandrel 40 can in effect become a part of drill string 20 . Sleeve 150 fits over mandrel 40 and becomes rotatably and sealably connected to mandrel 40 . Mandrel 40 can include shoulder 100 to supper sleeve 150 . Mandrel 40 can include one or more radial inlet ports 140 fluidly connecting central longitudinal passage 90 to recessed area 130 . Recessed area 130 preferably forms a circumferential recess along the perimeter of mandrel 40 and between packing support areas 131 , 132 . In such manner recessed area will remain fluidly connected with radial passage 190 and inlet 200 of sleeve 150 (see FIGS. 4 , 6 ). To reduce friction between mandrel 40 and packing units 305 , 415 ( FIG. 6 ) and increase the life expectancy of packing units 305 , 415 , packing support areas 131 , 132 can be coated and/or sprayed welded with a materials of various compositions, such as hard chrome, nickel/chrome or nickel/aluminum (95 percent nickel and 5 percent aluminum) A material which can be used for coating by spray welding is the chrome alloy TAFA 95MX Ultrahard Wire (Armacor M) manufactured by TAFA Technologies, Inc., 146 Pembroke Road, Concord New Hampshire. TAFA 95 MX is an alloy of the following composition: Chromium 30 percent; Boron 6 percent; Manganese 3 percent; Silicon 3 percent; and Iron balance. The TAFA 95 MX can be combined with a chrome steel. Another material which can be used for coating by spray welding is TAFA BONDARC WIRE—75B manufactured by TAFA Technologies, Inc. TAFA BONDARC WIRE—75B is an alloy containing the following elements: Nickel 94 percent; Aluminum 4.6 percent; Titanium 0.6 percent; Iron 0.4 percent; Manganese 0.3 percent; Cobalt 0.2 percent; Molybdenum 0.1 percent; Copper 0.1 percent; and Chromium 0.1 percent. Another material which can be used for coating by spray welding is the nickel chrome alloy TAFALOY NICKEL-CHROME-MOLY WIRE-71T manufactured by TAFA Technologies, Inc. TAFALOY NICKEL-CHROME-MOLY WIRE-71T is an alloy containing the following elements: Nickel 61.2 percent; Chromium 22 percent; Iron 3 percent; Molybdenum 9 percent; Tantalum 3 percent; and Cobalt 1 percent. Various combinations of the above alloys can also be used for the coating/spray welding. Packing support areas 131 , 132 can also be coated by a plating method, such as electroplating. The surface of support areas 131 , 132 can be ground/polished/finished to a desired finish to reduce friction and wear between support areas 131 , 132 and packing units 305 , 415 . FIG. 4 is a sectional view of sleeve 150 which can be incorporated into top drive swivel 30 . FIG. 5 is a right hand sectional view of sleeve 150 taken along the lines 4 - 4 . Sleeve 150 can include central longitudinal passage 180 extending from upper end 160 through lower end 170 . Sleeve 150 can also include radial passage 190 and inlet 200 . Inlet 200 can be attached by welding or any other conventional type method of fastening such as a threaded connection. If welded the connection is preferably heat treated to remove residual stresses created by the welding procedure. Also shown is protruding section 155 along with upper and lower shoulders 156 , 157 . Lubrication port 210 can be included to provide lubrication for interior bearings. Packing ports 220 , 230 can also be included to provide the option of injecting packing material into the packing units 305 , 415 (see FIG. 6 ). A protective cover 240 can be placed around packing port 230 to protect packing injector 235 (see FIG. 6 ). Optionally, a second protective cover can be placed around packing port 220 , however, it is anticipated that protection will be provided by clamp 600 and inlet 200 . Sleeve 150 can include peripheral groove 205 for attachment of clamp 600 . Additionally, key way 206 can be provided for insertion of a key 700 . FIG. 5 illustrates how central longitudinal passage 180 is fluidly connected to inlet 200 through radial passage 190 . It is preferred that welding be performed using Preferred Industries Welding Procedure number T3, 1550REV-A 4140HT (285/311 bhn) RMT to 4140 HT (285/311 bhn (RMT) It is also preferred that welds be X-ray tested, magnetic particle tested, and stress relieved. FIG. 6 is a sectional view of the assembled top drive swivel 30 of FIG. 2 . As can be seen sleeve 150 slides over mandrel 40 . Bearings 145 , 146 rotatably connect sleeve 150 to mandrel 40 . Bearings 145 , 146 are preferably thrust bearings although many conventionally available bearing will adequately function, including conical and ball bearings. Packing units 305 , 415 sealingly connect sleeve 150 to mandrel 40 . Inlet 200 of sleeve 150 is and remains fluidly connected to central longitudinal passage 90 of mandrel 40 . Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 . Recessed area 130 and protruding section 155 form a peripheral recess between mandrel 40 and sleeve 150 . The fluid pathway from inlet 200 to outlet at lower end 60 of central longitudinal passage 90 is as follows: entering inlet 200 (arrow 201 ); passing through radial passage 190 (arrow 202 ); passing through recessed area 130 (arrow 202 ); passing through one of the plurality of radial inlet ports 140 (arrow 202 ), passing through central longitudinal passage 90 (arrow 203 ); and exiting mandrel 40 via lower end 60 at pin connection 80 (arrows 204 , 205 ). FIG. 6A shows a blown up schematic view of packing unit 305 . Packing unit 305 can comprise packing end 320 ; packing ring 330 , packing ring 340 , packing lubrication ring 350 , packing end 360 , packing ring 370 , packing ring 380 , packing ring 390 , packing ring 400 , and packing end 410 . Packing unit 305 sealing connects mandrel 40 and sleeve 150 . Packing unit 305 can be encased by packing retainer nut 310 and shoulder 156 of protruding section 155 . Packing retainer nut 310 can be a ring which threadably engages sleeve 150 at threaded area 316 . Packing retainer nut 310 and shoulder 156 squeeze packing unit 305 to obtain a good seal between mandrel 40 and sleeve 150 . Set screw 315 can be used to lock packing retainer nut 310 in place and prevent retainer nut 310 from loosening during operation. Set screw 315 can be threaded into bore 314 and lock into receiving area 317 on sleeve 150 . Packing unit 415 can be constructed substantially similar to packing unit 305 . The materials for packing unit 305 and packing unit 415 can be similar. Packing end 320 is preferably a bronze female packing end. Packing ring 330 is preferably a “Vee” packing ring—Teflon such as that supplied by CDI part number 0500700-VS-720 Carbon Reflon (having 2 percent carbon). Packing ring 340 is preferably a “Vee” packing ring—Rubber such as that supplied by CDI part number 0500700-VS-850NBR Aramid. Packing lubrication ring 350 is described below in the discussion regarding FIGS. 6B and 6C . Packing end 360 preferably a bronze female packing end. Packing ring 370 is preferably a “Vee” packing ring—Teflon such as that supplied by CDI part number 0500700-VS-720 Carbon Reflon (having 2 percent carbon). Packing ring 380 is preferably a “Vee” packing ring—Rubber such as that supplied by CDI part number 0500700-VS-850NBR Aramid. Packing ring 390 is preferably a “Vee” packing ring—Teflon such as that supplied by CDI part number 0500700-VS-720 Carbon Reflon (having 2 percent carbon). Packing ring 400 is preferably a “Vee” packing ring—Rubber such as that supplied by CDI part number 0500700-VS-850NBR Aramid. Packing end 410 is preferably a bronze male packing ring. Various alternative materials for packing rings can be used such as standard chevron packing rings of standard packing materials. Bronze rings preferably meet or exceed an SAE 660 standard. A packing injection option can be provided for top drive swivel 30 . Injection fitting 225 can be used to inject additional packing material such as teflon into packing unit 305 . Head 226 for injection fitting 225 can be removed and packing material can then be inserting into fitting 225 . Head 226 can then be screwed back into injection fitting 225 which would push packing material through fitting 225 and into packing port 220 . The material would then be pushed into packing ring 350 . Packing ring 350 can comprise radial port 352 and transverse port 351 . The material would proceed through radial port 352 and exit through transverse port 351 . The material would tend to push out and squeeze packing rings 340 , 330 , 320 and packing rings 360 , 370 , 380 , 390 , 400 tending to create a better seal between packing unit 305 with mandrel 40 and sleeve 150 . The interaction between injection fitting 235 and packing unit 415 can be substantially similar to the interaction between injection fitting 225 and packing unit 305 . A conventionally available material which can be used for packing injection fittings 225 , 235 is DESCO™ 625 Pak part number 6242-12 in the form of a 1 inch by ⅜ inch stick and distributed by Chemola Division of South Coast Products, Inc., Houston, Tex. In FIG. 6 , injection fitting 235 is shown ninety degrees out of phase and, is preferably located as shown in FIG. 9 . Injection fittings 225 , 235 have a dual purpose: (a) provide an operator a visual indication whether there has been any leakage past either packing units 305 , 415 and (b) allow the operator to easily inject additional packing material and stop seal leakage without removing top drive swivel 30 from drill string 20 . FIGS. 6B and 6C shows top and side views of packing injection ring 350 . Packing injection ring 350 includes a male end 355 at its top and a flat end 356 at its rear. Ring 350 includes peripheral groove 353 around its perimeter. Optionally, ring 350 can include interior groove along its interior. A plurality of transverse ports 351 , 351 ′, 351 ″, 351 ″′, etc. extending from male end 355 to flat end 356 can be included and can be evenly spaced along the circumference of ring 350 . A plurality of radial ports 352 , 352 ′, 352 ″, 352 ″′, etc. can be included extending from peripheral groove 353 and respectively intersecting transverse ports 351 , 351 ′, 351 ″, 351 ″′, etc. Preferably, the radial ports can extend from peripheral groove 353 through interior groove 354 . Retainer nut 800 can be used to maintain sleeve 150 on mandrel 40 . Retainer nut 800 can threadably engage mandrel 40 at threaded area 801 . Set screw 890 can be used to lock in place retainer nut 800 and prevent nut 800 from loosening during operation. Set screw 890 threadably engages retainer nut 800 through bore 900 and sets in one of a plurality of receiving portions 910 formed in mandrel 40 . Retaining nut 800 can also include grease injection fitting 880 for lubricating bearing 145 . Wiper ring 271 set in area 270 protects against dirt and other items from entering between the sleeve 150 and mandrel 40 . Grease ring 291 set in area 290 holds in lubricant for bearing 145 . Bearing 146 can be lubricated through grease injection fitting 211 and lubrication port 210 . Bearing 145 can be lubricated through grease injection fitting 881 and lubrication port 880 . FIG. 7 is a top view of clamp 600 which can be incorporated into top drive swivel 30 . FIG. 8 is a side view of clamp 600 . Clamp 600 comprises first portion 610 and second portion 620 . First and second portions 610 , 620 can be removably attached by fasteners 670 , 680 . Clamp 600 fits in groove 605 of sleeve 150 ( FIG. 6 ). Key 700 can be included in keyway 690 . A corresponding keyway 691 is included in sleeve 150 of top drive swivel 30 . Keyways 690 , 691 and key 700 prevent clamp 600 from rotating relative to sleeve 150 . A second key 720 can be installed in keyways 710 , 711 . Shackles 650 , 660 can be attached to clamp 600 to facilitate handing top drive swivel 30 when clamp 600 is attached. Torque arms 630 , 640 can be included to allow attachment of clamp 600 (and sleeve 150 ) to a stationary part of top drive rig 1 and prevent sleeve 150 from rotating while drill string 20 is being rotated by top drive 10 (and top drive swivel 30 is installed in drill string 20 ). Torque arms 630 , 640 are provided with holes for attaching restraining shackles. Restrained torque arms 630 , 640 prevent sleeve 150 from rotating while mandrel 40 is being spun. Otherwise, frictional forces between packing units 305 , 415 and packing support areas 131 , 135 of rotating mandrel 40 would tend to also rotate sleeve 150 . Clamp 600 is preferably fabricated from 4140 heat treated steel being machined to fit around sleeve 150 . FIG. 9 is an overall perspective view (and partial sectional view) of top drive swivel 30 . Sleeve 150 is shown rotatably connected to mandrel 40 . Bearings 145 , 146 allow sleeve 150 to rotate in relation to mandrel 40 . Packing units 305 , 415 sealingly connect sleeve 150 to mandrel 40 . Retaining nut 800 retains sleeve 150 on mandrel 40 . Inlet 200 of sleeve 150 is fluidly connected to central longitudinal passage 90 of mandrel 40 . Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 . Recessed area 130 and protruding section 155 form a peripheral recess between mandrel 40 and sleeve 150 . The fluid pathway from inlet 200 to outlet at lower end 60 of central longitudinal passage 90 is as follows: entering inlet. 200 ; passing through radial passage 190 ; passing through recessed area 130 ; passing through one of the plurality of radial inlet ports 40 ; passing through central longitudinal passage 90 ; and exiting mandrel 40 through central longitudinal passage 90 at lower end 60 and pin connection 80 . In FIG. 9 , injection fitting 225 is shown ninety degrees out of phase and, for protection, is preferably located between inlet 200 and clamp 600 . Mandrel 40 takes substantially all of the structural load from drill string 20 . The overall length of mandrel 40 is preferably 52 and 5/16 inches. Mandrel 40 can be machined from a single continuous piece of heat treated steel bar stock. NC50 is preferably the API Tool Joint Designation for the box connection 70 and pin connection 80 . Such tool joint designation is equivalent to and interchangeable with 4½ inch IF (Internally Flush), 5 inch XH (Extra Hole) and 5½ inch DSL (Double Stream Line) connections. Additionally, it is preferred that the box connection 70 and pin connection 80 meet the requirements of API specifications 7 and 7G for new rotary shouldered tool joint connections having 6⅝ inch outer diameter and a 2¾ inch inner diameter. The Strength and Design Formulas of API 7G—Appendix A provides the following load carrying specification for mandrel 40 of top drive swivel 30 : (a) 1,477 pounds tensile load at the minimum yield stress; (b) 62,000 foot-pounds torsion load at the minimum torsional yield stress; and (c) 37,200 foot-pounds recommended minimum make up torque. Mandrel 40 can be machined from 4340 heat treated bar stock. Sleeve 150 is preferably fabricated from 4140 heat treated round mechanical tubing having the following properties: (120,000 psi minimum tensile strength, 100,000 psi minimum yield strength, and 285/311 Brinell Hardness Range). The external diameter of sleeve 150 is preferably about 11 inches. Sleeve 150 preferably resists high internal pressures of fluid passing through inlet 200 . Preferably top drive swivel 30 with sleeve 150 will withstand a hydrostatic pressure test of 12,500 psi. At this pressure the stress induced in sleeve 150 is preferably only about 24.8 percent of its material's yield strength. At a preferable working pressure of 7,500 psi, there is preferably a 6.7:1 structural safety factor for sleeve 150 . To minimize flow restrictions through top drive swivel 30 , large open areas are preferred. Preferably each area of interest throughout top drive swivel 30 is larger than the inlet service port area 200 . Inlet 200 is preferably 3 inches having a flow area of 4.19 square inches. The flow area of the annular space between sleeve 150 and mandrel 40 is preferably 20.81 square inches. The flow area through the plurality of radial inlet ports 140 is preferably 7.36 square inches. The flow area through central longitudinal bore 90 is preferably 5.94 square inches. The following is a list of reference numerals: LIST FOR REFERENCE NUMERALS (Part No.) Reference (Description) Numeral Description 1 rig 2 crown block 3 cable means 4 travelling block 5 hook 6 gooseneck 7 swivel 8 drilling fluid line 10 top drive unit 11 draw works 12 cable 13 rotary table 14 well bore 15 guide rail 16 support 17 support 18 drill pipe 19 drill string 20 drill string or work string 30 swivel 31 hose 40 swivel mandrel 50 upper end 60 lower end 70 box connection 80 pin connection 90 central longitudinal passage 100 shoulder 101 outer surface of shoulder 102 upper surface of shoulder 110 interior surface 120 external surface (mandrel) 130 recessed area 131 packing support area 132 packing support area 140 radial inlet ports (a plurality) 145 bearing (preferably combination 6.875 inch bearing cone, Timken Part number 67786, and 9.75 inch bearing cup bearing cup, Timken part number 67720) 146 bearing (preferably combination 7 inch bearing cone, Timken Part number 67791, and 9.75 inch bearing cup bearing cup, Timken part number 67720) 150 swivel sleeve 155 protruding section 156 shoulder 157 shoulder 158 packing support area 159 packing support area 160 upper end 170 lower end 180 central longitudinal passage 190 radial passage 200 inlet 201 arrow 202 arrow 203 arrow 204 arrow 205 peripheral groove 206 key way 210 lubrication port 211 grease injection fitting (preferably grease zerk (¼ - 28 td. in. streight, mat.-monel Alemite part number 1966-B) 220 packing port 225 injection fitting(preferably packing injection fitting (10,000 psi) Vesta - PGI Manufacturing part number PF10N4- 10)(alternatively Pressure ReliefTool for packing injection fitting Vesta - PGI Manufacturing part number PRT - PIF 12–20) 226 head 230 packing port 235 injection fitting (preferably packing injection fitting (10,000 psi) Vesta - PGI Manufacturing part number PF10N4- 10)(alternatively Pressure ReliefTool for packing injection fitting Vesta - PGI Manufacturing part number PRT - PIF 12–20) 240 cover 250 upper shoulder 260 lower shoulder 270 area for wiper ring 271 wiper ring (preferably Parker part number 959-65) 280 area for wiper ring 281 wiper ring (preferably Parker part number 959-65) 290 area for grease ring 291 grease ring (preferably Parker part number 2501000 Standard Polypak) 300 area for grease ring 301 grease ring (preferably Parker part number 2501000 Standard Polypak) 305 packing unit 310 packing retainer nut 314 bore for set screw 315 set screw for packing retainer nut 316 threaded area 317 set screw for receiving area 320 packing end 330 packing ring 340 packing ring 350 packing injection ring 351 transverse port 352 radial port 353 peripheral groove 354 interior groove 355 male end 356 flat end 360 packing end 370 packing ring 380 packing ring 390 packing ring 400 packing ring 410 packing end 415 packing unit 420 packing retainer nut 425 set screw for packing retainer nut 430 packing end 440 packing ring 450 packing ring 460 packing lubrication ring 470 packing end 480 packing ring 490 packing ring 500 packing ring 510 packing ring 520 packing end 600 clamp 605 groove 610 first portion 620 second portion 630 torque arm 640 torque arm 650 shackle 660 shackle 670 fastener 680 fastener 690 keyway 691 keyway 700 key 710 keyway 711 keyway 720 key 730 peripheral groove 800 retaining nut 801 threaded area 810 outer surface 820 inclined portion 830 bore 840 inner surface 850 threaded portion 860 upper surface 870 bottom surface 880 lubrication port 881 grease injection fitting (preferably grease zerk (¼ - 28 td. in. streight, mat.-monel Alemite part number 1966-B) 890 set screw 900 bore for set screw 910 receiving portion for set screw All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise. It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above. Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention set forth in the appended claims. The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.
For use with a top drive power unit supported for connection with a well string in a well bore to selectively impart longitudinal and/or rotational movement to the well string, a feeder for supplying a pumpable substance such as cement and the like from an external supply source to the interior of the well string in the well bore without first discharging it through the top drive power unit including a mandrel extending through a sleeve which is sealably and rotatably supported thereon for relative rotation between the sleeve and mandrel. The mandrel and sleeve have flow passages for communicating the pumpable substance from an external source to discharge through the sleeve and mandrel and into the interior of the well string below the top drive power unit. The unit can include a packing injection system, clamp, and novel packing configuration.
Briefly summarize the invention's components and working principles as described in the document.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS Priority of U.S. Provisional Patent Application Ser.", "No. 60/409,177, filed Sep. 9, 2002, incorporated herein by reference, is hereby claimed.", "STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not applicable REFERENCE TO A “MICROFICHE APPENDIX”", "Not applicable BACKGROUND In top drive rigs, the use of a top drive unit, or top drive power unit is employed to rotate drill pipe, or well string in a well bore.", "Top drive rigs can include spaced guide rails and a drive frame movable along the guide rails and guiding the top drive power unit.", "The travelling block supports the drive frame through a hook and swivel, and the driving block is used to lower or raise the drive frame along the guide rails.", "For rotating the drill or well string, the top drive power unit includes a motor connected by gear means with a rotatable member both of which are supported by the drive frame.", "During drilling operations, when it is desired to “trip”", "the drill pipe or well string into or out of the well bore, the drive frame can be lowered or raised.", "Additionally, during servicing operations, the drill string can be moved longitudinally into or out of the well bore.", "The stem of the swivel communicates with the upper end of the rotatable member of the power unit in a manner well known to those skilled in the art for supplying fluid, such as a drilling fluid or mud, through the top drive unit and into the drill or work string.", "The swivel allows drilling fluid to pass through and be supplied to the drill or well string connected to the lower end of the rotatable member of the top drive power unit as the drill string is rotated and/or moved up and down.", "Top drive rigs also can include elevators are secured to and suspended from the frame, the elevators being employed when it is desired to lower joints of drill string into the well bore, or remove such joints from the well bore.", "At various times top drive operations, beyond drilling fluid, require various substances to be pumped downhole, such as cement, chemicals, epoxy resins, or the like.", "In many cases it is desirable to supply such substances at the same time as the top drive unit is rotating and/or moving the drill or well string up and/or down, but bypassing the top drive's power unit so that the substances do not damage/impair the unit.", "Additionally, it is desirable to supply such substances without interfering with and/or intermittently stopping longitudinal and/or rotational movement by the top drive unit of the drill or well string.", "A need exists for a device facilitating insertion of various substances downhole through the drill or well string, bypassing the top drive unit, while at the same time allowing the top drive unit to rotate and/or move the drill or well string.", "One example includes cementing a string of well bore casing.", "In some casing operations it is considered good practice to rotate the string of casing when it is being cemented in the wellbore.", "Such rotation is believed to facilitate better cement distribution and spread inside the annular space between the casing's exterior and interior of the well bore.", "In such operations the top drive unit can be used to both support and continuously rotate/intermittently reciprocate the string of casing while cement is pumped down the string's interior.", "During this time it is desirable to by-pass the top drive unit to avoid possible damage to any of its portions or components.", "The following U.S. patents are incorporated herein by reference: U.S. Pat. No. 4,722,389.", "While certain novel features of this invention shown and described below are pointed out in the annexed claims, the invention is not intended to be limited to the details specified, since a person of ordinary skill in the relevant art will understand that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation may be made without departing in any way from the spirit of the present invention.", "No feature of the invention is critical or essential unless it is expressly stated as being “critical”", "or “essential.”", "BRIEF SUMMARY The apparatus of the present invention solves the problems confronted in the art in a simple and straightforward manner.", "The invention herein broadly relates to an assembly having a top drive arrangement for rotating and longitudinally moving a drill or well string.", "In one embodiment the present invention includes a swivel apparatus, the swivel generally comprising a mandrel and a sleeve, the swivel being especially useful for top drive rigs.", "The sleeve can be rotatably and sealably connected to the mandrel.", "The swivel can be incorporated into a drill or well string and enabling string sections both above and below the sleeve to be rotated in relation to the sleeve.", "Additionally, the swivel provides a flow path between the exterior of the sleeve and interior of the mandrel while the drill string is being moved in a longitudinal direction (up or down) and/or being rotated/reciprocated.", "The interior of the mandrel can be fluidly connected to the longitudinal bore of casing or drill string thus providing a path from the sleeve to the interior of the casing/drill string.", "In one embodiment an object of the present invention is to provide a method and apparatus for servicing a well wherein a swivel is connected to and below a top drive unit for conveying pumpable substances from an external supply through the swivel for discharge into the well string, but bypassing the top drive unit.", "In another embodiment of the present invention is provided a method of conducting servicing operations in a well bore, such as cementing, comprising the steps of moving a top drive unit longitudinally and/or rotationally to provide longitudinal movement and/or rotation/reciprocation in the well bore of a well string suspended from the top drive unit, rotating the drill or well string and supplying a pumpable substance to the well bore in which the drill or well string is manipulated by introducing the pumpable substance at a point below the top drive power unit and into the well string.", "In other embodiments of the present invention a swivel placed below the top drive unit can be used to perform jobs such as spotting pills, squeeze work, open formation integrity work, kill jobs, fishing tool operations with high pressure pumps, sub-sea stack testing, rotation of casing during side tracking, and gravel pack or frack jobs.", "In still other embodiments a top drive swivel can be used in a method of pumping loss circulation material (LCM) into a well to plug/seal areas of downhole fluid loss to the formation and in high speed milling jobs using cutting tools to address down hole obstructions.", "In other embodiments the top drive swivel can be used with free point indicators and shot string or cord to free stuck pipe where pumpable substances are pumped downhole at the same time the downhole string/pipe/free point indicator is being rotated and/or-reciprocated.", "In still other embodiments the top drive swivel can be used for setting hook wall packers and washing sand.", "In still other embodiments the top drive swivel can be used for pumping pumpable substances downhole when repairs/servicing is being done to the top drive unit and rotation of the downhole drill string is being accomplished by the rotary table.", "Such use for rotation and pumping can prevent sticking/seizing of the drill string downhole.", "In this application safety valves, such as TIW valves, can be placed above and below the top drive swivel to enable routing of fluid flow and to ensure well control.", "The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms.", "BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: FIG. 1 is a schematic view showing a top drive rig with one embodiment of a top drive swivel incorporated in the drill string;", "FIG. 2 is a schematic view of one embodiment of a top drive swivel;", "FIG. 3 is a sectional view of a mandrel which can be incorporated in the top drive swivel of FIG. 2 ;", "FIG. 4 is a sectional view of a sleeve which can be incorporated into the top drive swivel of FIG. 2 ;", "FIG. 5 is a right hand side view of the sleeve of FIG. 4 ;", "FIG. 6 is a sectional view of the top drive swivel of FIG. 2 ;", "FIG. 6A is a sectional view of the packing unit shown in FIG. 6 ;", "FIG. 6B is a top view of the packing injection ring shown in FIGS. 6 and 6A ;", "FIG. 6C is a side view section of the packing injection ring shown in FIG. 6B ;", "FIG. 7 is a top view of a clamp which can be incorporated into the top drive swivel of FIG. 2 ;", "FIG. 8 is a side view of the clamp of FIG. 7 ;", "FIG. 9 is a perspective view and partial sectional view of the top drive swivel shown in FIG. 2 .", "DETAILED DESCRIPTION Detailed descriptions of one or more preferred embodiments are provided herein.", "It is to be understood, however, that the present invention may be embodied in various forms.", "Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in any appropriate system, structure or manner.", "FIG. 1 is a schematic view showing a top drive rig 1 with one embodiment of a top drive swivel 30 incorporated into drill string 20 .", "FIG. 1 is shows a rig 1 having a top drive unit 10 .", "Rig 5 comprises-supports 16 , 17 ;", "crown block 2 ;", "traveling block 4 ;", "and hook 5 .", "Draw works 11 uses cable 12 to move up and down traveling block 4 , top drive unit 10 , and drill string 20 .", "Traveling block 4 supports top drive unit 10 .", "Top drive unit 10 supports drill string 20 .", "During drilling operations, top drive unit 10 can be used to rotate drill string 20 which enters wellbore 14 .", "Top drive unit 10 can ride along guide rails 15 as unit 10 is moved up and down.", "Guide rails 15 prevent top drive unit 10 itself from rotating as top drive unit 10 rotates drill string 20 .", "During drilling operations drilling fluid can be supplied downhole through drilling fluid line 8 and gooseneck 6 .", "At various times top drive operations, beyond drilling fluid, require substances to be pumped downhole, such as cement, chemicals, epoxy resins, or the like.", "In many cases it is desirable to supply such substances at the same time as top drive unit 10 is rotating and/or moving drill or well string 20 up and/or down and bypassing top drive unit 10 so that the substances do not damage/impair top drive unit 10 .", "Additionally, it is desirable to supply such substances without interfering with and/or intermittently stopping longitudinal and/or rotational movements of drill or well string 20 being moved/rotated by top drive unit 10 .", "This can be accomplished by using top drive swivel 30 .", "Top drive swivel 30 can be installed between top drive unit 10 and drill string 20 .", "One or more joints of drill pipe 18 can be placed between top drive unit 10 and swivel 30 .", "Additionally, a valve can be placed between top drive swivel 30 and top drive unit 10 .", "Pumpable substances can be pumped through hose 31 , swivel 30 , and into the interior of drill string 20 thereby bypassing top drive unit 10 .", "Top drive swivel 30 is preferably sized to be connected to drill string 20 such as 4½ inch IF API drill pipe or the size of the drill pipe to which swivel 30 is connected to.", "However, cross-over subs can also be used between top drive swivel 30 and connections to drill string 20 .", "FIG. 2 is a schematic view of one embodiment of a top drive swivel 30 .", "Top drive swivel 30 can be comprised of mandrel 40 and sleeve 150 .", "Sleeve 150 is rotatably and sealably connected to mandrel 30 .", "Accordingly, when mandrel 40 is rotated, sleeve 150 can remain stationary to an observer insofar as rotation is concerned.", "As will be discussed later inlet 200 of sleeve 150 is and remains fluidly connected to a the central longitudinal passage 90 of mandrel 40 .", "Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 .", "FIG. 3 is a sectional view of mandrel 40 which can be incorporated in the top drive swivel 30 .", "Mandrel 40 is comprised of upper end 50 and lower end 60 .", "Central longitudinal passage 90 extends from upper end 50 through lower end 60 .", "Lower end 60 can include a pin connection or any other conventional connection.", "Upper end 50 can include box connection 70 or any other conventional connection.", "Mandrel 40 can in effect become a part of drill string 20 .", "Sleeve 150 fits over mandrel 40 and becomes rotatably and sealably connected to mandrel 40 .", "Mandrel 40 can include shoulder 100 to supper sleeve 150 .", "Mandrel 40 can include one or more radial inlet ports 140 fluidly connecting central longitudinal passage 90 to recessed area 130 .", "Recessed area 130 preferably forms a circumferential recess along the perimeter of mandrel 40 and between packing support areas 131 , 132 .", "In such manner recessed area will remain fluidly connected with radial passage 190 and inlet 200 of sleeve 150 (see FIGS. 4 , 6 ).", "To reduce friction between mandrel 40 and packing units 305 , 415 ( FIG. 6 ) and increase the life expectancy of packing units 305 , 415 , packing support areas 131 , 132 can be coated and/or sprayed welded with a materials of various compositions, such as hard chrome, nickel/chrome or nickel/aluminum (95 percent nickel and 5 percent aluminum) A material which can be used for coating by spray welding is the chrome alloy TAFA 95MX Ultrahard Wire (Armacor M) manufactured by TAFA Technologies, Inc., 146 Pembroke Road, Concord New Hampshire.", "TAFA 95 MX is an alloy of the following composition: Chromium 30 percent;", "Boron 6 percent;", "Manganese 3 percent;", "Silicon 3 percent;", "and Iron balance.", "The TAFA 95 MX can be combined with a chrome steel.", "Another material which can be used for coating by spray welding is TAFA BONDARC WIRE—75B manufactured by TAFA Technologies, Inc. TAFA BONDARC WIRE—75B is an alloy containing the following elements: Nickel 94 percent;", "Aluminum 4.6 percent;", "Titanium 0.6 percent;", "Iron 0.4 percent;", "Manganese 0.3 percent;", "Cobalt 0.2 percent;", "Molybdenum 0.1 percent;", "Copper 0.1 percent;", "and Chromium 0.1 percent.", "Another material which can be used for coating by spray welding is the nickel chrome alloy TAFALOY NICKEL-CHROME-MOLY WIRE-71T manufactured by TAFA Technologies, Inc. TAFALOY NICKEL-CHROME-MOLY WIRE-71T is an alloy containing the following elements: Nickel 61.2 percent;", "Chromium 22 percent;", "Iron 3 percent;", "Molybdenum 9 percent;", "Tantalum 3 percent;", "and Cobalt 1 percent.", "Various combinations of the above alloys can also be used for the coating/spray welding.", "Packing support areas 131 , 132 can also be coated by a plating method, such as electroplating.", "The surface of support areas 131 , 132 can be ground/polished/finished to a desired finish to reduce friction and wear between support areas 131 , 132 and packing units 305 , 415 .", "FIG. 4 is a sectional view of sleeve 150 which can be incorporated into top drive swivel 30 .", "FIG. 5 is a right hand sectional view of sleeve 150 taken along the lines 4 - 4 .", "Sleeve 150 can include central longitudinal passage 180 extending from upper end 160 through lower end 170 .", "Sleeve 150 can also include radial passage 190 and inlet 200 .", "Inlet 200 can be attached by welding or any other conventional type method of fastening such as a threaded connection.", "If welded the connection is preferably heat treated to remove residual stresses created by the welding procedure.", "Also shown is protruding section 155 along with upper and lower shoulders 156 , 157 .", "Lubrication port 210 can be included to provide lubrication for interior bearings.", "Packing ports 220 , 230 can also be included to provide the option of injecting packing material into the packing units 305 , 415 (see FIG. 6 ).", "A protective cover 240 can be placed around packing port 230 to protect packing injector 235 (see FIG. 6 ).", "Optionally, a second protective cover can be placed around packing port 220 , however, it is anticipated that protection will be provided by clamp 600 and inlet 200 .", "Sleeve 150 can include peripheral groove 205 for attachment of clamp 600 .", "Additionally, key way 206 can be provided for insertion of a key 700 .", "FIG. 5 illustrates how central longitudinal passage 180 is fluidly connected to inlet 200 through radial passage 190 .", "It is preferred that welding be performed using Preferred Industries Welding Procedure number T3, 1550REV-A 4140HT (285/311 bhn) RMT to 4140 HT (285/311 bhn (RMT) It is also preferred that welds be X-ray tested, magnetic particle tested, and stress relieved.", "FIG. 6 is a sectional view of the assembled top drive swivel 30 of FIG. 2 .", "As can be seen sleeve 150 slides over mandrel 40 .", "Bearings 145 , 146 rotatably connect sleeve 150 to mandrel 40 .", "Bearings 145 , 146 are preferably thrust bearings although many conventionally available bearing will adequately function, including conical and ball bearings.", "Packing units 305 , 415 sealingly connect sleeve 150 to mandrel 40 .", "Inlet 200 of sleeve 150 is and remains fluidly connected to central longitudinal passage 90 of mandrel 40 .", "Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 .", "Recessed area 130 and protruding section 155 form a peripheral recess between mandrel 40 and sleeve 150 .", "The fluid pathway from inlet 200 to outlet at lower end 60 of central longitudinal passage 90 is as follows: entering inlet 200 (arrow 201 );", "passing through radial passage 190 (arrow 202 );", "passing through recessed area 130 (arrow 202 );", "passing through one of the plurality of radial inlet ports 140 (arrow 202 ), passing through central longitudinal passage 90 (arrow 203 );", "and exiting mandrel 40 via lower end 60 at pin connection 80 (arrows 204 , 205 ).", "FIG. 6A shows a blown up schematic view of packing unit 305 .", "Packing unit 305 can comprise packing end 320 ;", "packing ring 330 , packing ring 340 , packing lubrication ring 350 , packing end 360 , packing ring 370 , packing ring 380 , packing ring 390 , packing ring 400 , and packing end 410 .", "Packing unit 305 sealing connects mandrel 40 and sleeve 150 .", "Packing unit 305 can be encased by packing retainer nut 310 and shoulder 156 of protruding section 155 .", "Packing retainer nut 310 can be a ring which threadably engages sleeve 150 at threaded area 316 .", "Packing retainer nut 310 and shoulder 156 squeeze packing unit 305 to obtain a good seal between mandrel 40 and sleeve 150 .", "Set screw 315 can be used to lock packing retainer nut 310 in place and prevent retainer nut 310 from loosening during operation.", "Set screw 315 can be threaded into bore 314 and lock into receiving area 317 on sleeve 150 .", "Packing unit 415 can be constructed substantially similar to packing unit 305 .", "The materials for packing unit 305 and packing unit 415 can be similar.", "Packing end 320 is preferably a bronze female packing end.", "Packing ring 330 is preferably a “Vee”", "packing ring—Teflon such as that supplied by CDI part number 0500700-VS-720 Carbon Reflon (having 2 percent carbon).", "Packing ring 340 is preferably a “Vee”", "packing ring—Rubber such as that supplied by CDI part number 0500700-VS-850NBR Aramid.", "Packing lubrication ring 350 is described below in the discussion regarding FIGS. 6B and 6C .", "Packing end 360 preferably a bronze female packing end.", "Packing ring 370 is preferably a “Vee”", "packing ring—Teflon such as that supplied by CDI part number 0500700-VS-720 Carbon Reflon (having 2 percent carbon).", "Packing ring 380 is preferably a “Vee”", "packing ring—Rubber such as that supplied by CDI part number 0500700-VS-850NBR Aramid.", "Packing ring 390 is preferably a “Vee”", "packing ring—Teflon such as that supplied by CDI part number 0500700-VS-720 Carbon Reflon (having 2 percent carbon).", "Packing ring 400 is preferably a “Vee”", "packing ring—Rubber such as that supplied by CDI part number 0500700-VS-850NBR Aramid.", "Packing end 410 is preferably a bronze male packing ring.", "Various alternative materials for packing rings can be used such as standard chevron packing rings of standard packing materials.", "Bronze rings preferably meet or exceed an SAE 660 standard.", "A packing injection option can be provided for top drive swivel 30 .", "Injection fitting 225 can be used to inject additional packing material such as teflon into packing unit 305 .", "Head 226 for injection fitting 225 can be removed and packing material can then be inserting into fitting 225 .", "Head 226 can then be screwed back into injection fitting 225 which would push packing material through fitting 225 and into packing port 220 .", "The material would then be pushed into packing ring 350 .", "Packing ring 350 can comprise radial port 352 and transverse port 351 .", "The material would proceed through radial port 352 and exit through transverse port 351 .", "The material would tend to push out and squeeze packing rings 340 , 330 , 320 and packing rings 360 , 370 , 380 , 390 , 400 tending to create a better seal between packing unit 305 with mandrel 40 and sleeve 150 .", "The interaction between injection fitting 235 and packing unit 415 can be substantially similar to the interaction between injection fitting 225 and packing unit 305 .", "A conventionally available material which can be used for packing injection fittings 225 , 235 is DESCO™ 625 Pak part number 6242-12 in the form of a 1 inch by ⅜ inch stick and distributed by Chemola Division of South Coast Products, Inc., Houston, Tex.", "In FIG. 6 , injection fitting 235 is shown ninety degrees out of phase and, is preferably located as shown in FIG. 9 .", "Injection fittings 225 , 235 have a dual purpose: (a) provide an operator a visual indication whether there has been any leakage past either packing units 305 , 415 and (b) allow the operator to easily inject additional packing material and stop seal leakage without removing top drive swivel 30 from drill string 20 .", "FIGS. 6B and 6C shows top and side views of packing injection ring 350 .", "Packing injection ring 350 includes a male end 355 at its top and a flat end 356 at its rear.", "Ring 350 includes peripheral groove 353 around its perimeter.", "Optionally, ring 350 can include interior groove along its interior.", "A plurality of transverse ports 351 , 351 ′, 351 ″, 351 ″′, etc.", "extending from male end 355 to flat end 356 can be included and can be evenly spaced along the circumference of ring 350 .", "A plurality of radial ports 352 , 352 ′, 352 ″, 352 ″′, etc.", "can be included extending from peripheral groove 353 and respectively intersecting transverse ports 351 , 351 ′, 351 ″, 351 ″′, etc.", "Preferably, the radial ports can extend from peripheral groove 353 through interior groove 354 .", "Retainer nut 800 can be used to maintain sleeve 150 on mandrel 40 .", "Retainer nut 800 can threadably engage mandrel 40 at threaded area 801 .", "Set screw 890 can be used to lock in place retainer nut 800 and prevent nut 800 from loosening during operation.", "Set screw 890 threadably engages retainer nut 800 through bore 900 and sets in one of a plurality of receiving portions 910 formed in mandrel 40 .", "Retaining nut 800 can also include grease injection fitting 880 for lubricating bearing 145 .", "Wiper ring 271 set in area 270 protects against dirt and other items from entering between the sleeve 150 and mandrel 40 .", "Grease ring 291 set in area 290 holds in lubricant for bearing 145 .", "Bearing 146 can be lubricated through grease injection fitting 211 and lubrication port 210 .", "Bearing 145 can be lubricated through grease injection fitting 881 and lubrication port 880 .", "FIG. 7 is a top view of clamp 600 which can be incorporated into top drive swivel 30 .", "FIG. 8 is a side view of clamp 600 .", "Clamp 600 comprises first portion 610 and second portion 620 .", "First and second portions 610 , 620 can be removably attached by fasteners 670 , 680 .", "Clamp 600 fits in groove 605 of sleeve 150 ( FIG. 6 ).", "Key 700 can be included in keyway 690 .", "A corresponding keyway 691 is included in sleeve 150 of top drive swivel 30 .", "Keyways 690 , 691 and key 700 prevent clamp 600 from rotating relative to sleeve 150 .", "A second key 720 can be installed in keyways 710 , 711 .", "Shackles 650 , 660 can be attached to clamp 600 to facilitate handing top drive swivel 30 when clamp 600 is attached.", "Torque arms 630 , 640 can be included to allow attachment of clamp 600 (and sleeve 150 ) to a stationary part of top drive rig 1 and prevent sleeve 150 from rotating while drill string 20 is being rotated by top drive 10 (and top drive swivel 30 is installed in drill string 20 ).", "Torque arms 630 , 640 are provided with holes for attaching restraining shackles.", "Restrained torque arms 630 , 640 prevent sleeve 150 from rotating while mandrel 40 is being spun.", "Otherwise, frictional forces between packing units 305 , 415 and packing support areas 131 , 135 of rotating mandrel 40 would tend to also rotate sleeve 150 .", "Clamp 600 is preferably fabricated from 4140 heat treated steel being machined to fit around sleeve 150 .", "FIG. 9 is an overall perspective view (and partial sectional view) of top drive swivel 30 .", "Sleeve 150 is shown rotatably connected to mandrel 40 .", "Bearings 145 , 146 allow sleeve 150 to rotate in relation to mandrel 40 .", "Packing units 305 , 415 sealingly connect sleeve 150 to mandrel 40 .", "Retaining nut 800 retains sleeve 150 on mandrel 40 .", "Inlet 200 of sleeve 150 is fluidly connected to central longitudinal passage 90 of mandrel 40 .", "Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 .", "Recessed area 130 and protruding section 155 form a peripheral recess between mandrel 40 and sleeve 150 .", "The fluid pathway from inlet 200 to outlet at lower end 60 of central longitudinal passage 90 is as follows: entering inlet.", "200 ;", "passing through radial passage 190 ;", "passing through recessed area 130 ;", "passing through one of the plurality of radial inlet ports 40 ;", "passing through central longitudinal passage 90 ;", "and exiting mandrel 40 through central longitudinal passage 90 at lower end 60 and pin connection 80 .", "In FIG. 9 , injection fitting 225 is shown ninety degrees out of phase and, for protection, is preferably located between inlet 200 and clamp 600 .", "Mandrel 40 takes substantially all of the structural load from drill string 20 .", "The overall length of mandrel 40 is preferably 52 and 5/16 inches.", "Mandrel 40 can be machined from a single continuous piece of heat treated steel bar stock.", "NC50 is preferably the API Tool Joint Designation for the box connection 70 and pin connection 80 .", "Such tool joint designation is equivalent to and interchangeable with 4½ inch IF (Internally Flush), 5 inch XH (Extra Hole) and 5½ inch DSL (Double Stream Line) connections.", "Additionally, it is preferred that the box connection 70 and pin connection 80 meet the requirements of API specifications 7 and 7G for new rotary shouldered tool joint connections having 6⅝ inch outer diameter and a 2¾ inch inner diameter.", "The Strength and Design Formulas of API 7G—Appendix A provides the following load carrying specification for mandrel 40 of top drive swivel 30 : (a) 1,477 pounds tensile load at the minimum yield stress;", "(b) 62,000 foot-pounds torsion load at the minimum torsional yield stress;", "and (c) 37,200 foot-pounds recommended minimum make up torque.", "Mandrel 40 can be machined from 4340 heat treated bar stock.", "Sleeve 150 is preferably fabricated from 4140 heat treated round mechanical tubing having the following properties: (120,000 psi minimum tensile strength, 100,000 psi minimum yield strength, and 285/311 Brinell Hardness Range).", "The external diameter of sleeve 150 is preferably about 11 inches.", "Sleeve 150 preferably resists high internal pressures of fluid passing through inlet 200 .", "Preferably top drive swivel 30 with sleeve 150 will withstand a hydrostatic pressure test of 12,500 psi.", "At this pressure the stress induced in sleeve 150 is preferably only about 24.8 percent of its material's yield strength.", "At a preferable working pressure of 7,500 psi, there is preferably a 6.7:1 structural safety factor for sleeve 150 .", "To minimize flow restrictions through top drive swivel 30 , large open areas are preferred.", "Preferably each area of interest throughout top drive swivel 30 is larger than the inlet service port area 200 .", "Inlet 200 is preferably 3 inches having a flow area of 4.19 square inches.", "The flow area of the annular space between sleeve 150 and mandrel 40 is preferably 20.81 square inches.", "The flow area through the plurality of radial inlet ports 140 is preferably 7.36 square inches.", "The flow area through central longitudinal bore 90 is preferably 5.94 square inches.", "The following is a list of reference numerals: LIST FOR REFERENCE NUMERALS (Part No.) Reference (Description) Numeral Description 1 rig 2 crown block 3 cable means 4 travelling block 5 hook 6 gooseneck 7 swivel 8 drilling fluid line 10 top drive unit 11 draw works 12 cable 13 rotary table 14 well bore 15 guide rail 16 support 17 support 18 drill pipe 19 drill string 20 drill string or work string 30 swivel 31 hose 40 swivel mandrel 50 upper end 60 lower end 70 box connection 80 pin connection 90 central longitudinal passage 100 shoulder 101 outer surface of shoulder 102 upper surface of shoulder 110 interior surface 120 external surface (mandrel) 130 recessed area 131 packing support area 132 packing support area 140 radial inlet ports (a plurality) 145 bearing (preferably combination 6.875 inch bearing cone, Timken Part number 67786, and 9.75 inch bearing cup bearing cup, Timken part number 67720) 146 bearing (preferably combination 7 inch bearing cone, Timken Part number 67791, and 9.75 inch bearing cup bearing cup, Timken part number 67720) 150 swivel sleeve 155 protruding section 156 shoulder 157 shoulder 158 packing support area 159 packing support area 160 upper end 170 lower end 180 central longitudinal passage 190 radial passage 200 inlet 201 arrow 202 arrow 203 arrow 204 arrow 205 peripheral groove 206 key way 210 lubrication port 211 grease injection fitting (preferably grease zerk (¼ - 28 td.", "in.", "streight, mat.", "-monel Alemite part number 1966-B) 220 packing port 225 injection fitting(preferably packing injection fitting (10,000 psi) Vesta - PGI Manufacturing part number PF10N4- 10)(alternatively Pressure ReliefTool for packing injection fitting Vesta - PGI Manufacturing part number PRT - PIF 12–20) 226 head 230 packing port 235 injection fitting (preferably packing injection fitting (10,000 psi) Vesta - PGI Manufacturing part number PF10N4- 10)(alternatively Pressure ReliefTool for packing injection fitting Vesta - PGI Manufacturing part number PRT - PIF 12–20) 240 cover 250 upper shoulder 260 lower shoulder 270 area for wiper ring 271 wiper ring (preferably Parker part number 959-65) 280 area for wiper ring 281 wiper ring (preferably Parker part number 959-65) 290 area for grease ring 291 grease ring (preferably Parker part number 2501000 Standard Polypak) 300 area for grease ring 301 grease ring (preferably Parker part number 2501000 Standard Polypak) 305 packing unit 310 packing retainer nut 314 bore for set screw 315 set screw for packing retainer nut 316 threaded area 317 set screw for receiving area 320 packing end 330 packing ring 340 packing ring 350 packing injection ring 351 transverse port 352 radial port 353 peripheral groove 354 interior groove 355 male end 356 flat end 360 packing end 370 packing ring 380 packing ring 390 packing ring 400 packing ring 410 packing end 415 packing unit 420 packing retainer nut 425 set screw for packing retainer nut 430 packing end 440 packing ring 450 packing ring 460 packing lubrication ring 470 packing end 480 packing ring 490 packing ring 500 packing ring 510 packing ring 520 packing end 600 clamp 605 groove 610 first portion 620 second portion 630 torque arm 640 torque arm 650 shackle 660 shackle 670 fastener 680 fastener 690 keyway 691 keyway 700 key 710 keyway 711 keyway 720 key 730 peripheral groove 800 retaining nut 801 threaded area 810 outer surface 820 inclined portion 830 bore 840 inner surface 850 threaded portion 860 upper surface 870 bottom surface 880 lubrication port 881 grease injection fitting (preferably grease zerk (¼ - 28 td.", "in.", "streight, mat.", "-monel Alemite part number 1966-B) 890 set screw 900 bore for set screw 910 receiving portion for set screw All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise.", "All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise.", "It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.", "Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention set forth in the appended claims.", "The foregoing embodiments are presented by way of example only;", "the scope of the present invention is to be limited only by the following claims." ]
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates generally to improvements in long underwater power distribution systems for sonar and other sensor systems, and more particularly pertains to a new and improved method and apparatus for branching a single wire underwater power distribution system. [0003] 2. Description of the Prior Art [0004] A typical prior art single wire power distribution system 11 is shown in FIG. 1 wherein power is supplied to a plurality of nodes 13 , 15 and 17 located under the ocean 25 (saltwater). The nodes are typically sonar or other transducer or sensor systems which require a source of power emanating from a shore or ship based power source 12 . These prior art power delivery systems which utilize underwater cable have been optimized for use with a single wire 21 using the seawater 25 itself as a return 23 . This approach minimizes cable weight because only one power wire instead of two is needed. Moreover, the seawater provides a lower resistance return path than an actual wire would for long runs. [0005] In the prior art system illustrated in FIG. 1, power flow is from a shore based power source 12 through the conductive wire 21 in the cable, through each instrument and associated electronics node 13 , 15 and 17 until the end of the cable is reached. At the end of the cable, a low impedance connection 19 is made to the seawater 25 . This particular method efficiently delivers power over any length of cable to any desired number of instruments or electronic clusters (nodes). Typically, the power source on shore or ship is a constant current source with voltages supplied as required by each series node. [0006] The disadvantage of this prior art series power delivery system is that it prevents the power conductor 21 from branching at any location along its length. The power source 12 located on shore or on a ship is a constant current source. If a branch or wire connection were to occur in the conductor 21 , the current flow in each branch would be indeterminate. Both branches would be connected by low impedance 19 and 33 , respectively, to the seawater for return. As shown in FIG. 2, branching the current path at point 27 , for example, causing a single conductor 31 branch having a single node 29 therein with a lower voltage drop to receive all the current, while the other branch 21 with two nodes 13 and 15 therein, with a higher voltage drop, would receive no current. Such a parallel path system would not work. [0007] And yet in many cases, a series only connection of electronic nodes is not optimum. For example, if an area of the ocean is to be populated with an evenly spaced grid of instruments such as shown in FIG. 3, a series only connection scheme would require the cable to zigzag back and forth many times between the various nodes 13 , 15 , 17 , 35 and 37 , increasing power loss and installation cost. [0008] A shorter total cable length would be obtained if series and parallel node connections are allowed as shown in FIG. 4. As can be seen from FIG. 4, the parallel branching connections provide for a minimum of cable length for any installation. However, a direct implementation of a parallel path system will not work, as discussed above. [0009] Furthermore, cable installation is frequently required to be modified at some later date. If all the nodes are in series, such modification becomes very difficult. New nodes may only be added at the end of a cable. Adding new nodes in the middle, at the beginning or off to one side of the cable is difficult to the point where it might be easier to redeploy an entirely new cable. This procedure is very costly since the cable itself, and its deployment in the ocean are the largest single system cost. [0010] The present invention method and apparatus of allowing parallel branches to be effectively placed in series with any other branch while still maintaining the basic power delivery requirements permit more flexibility and better cable usage by allowing wide branching to provide a treelike structure, more efficient coverage, i.e., less cable use over a given area is provided. Moreover, the cable does not have to wind back and forth to cover a certain shaped area. The cable length is minimized, thereby minimizing insulation costs. Moreover, minimizing cable length minimizes power loss as the result of the cable resistance which is proportional to the length. [0011] The present invention also allows relatively easy modification of the original installation. Simply cutting the cable at any location along the main branch, a parallel branch may be introduced. If desired, provisions may be made at the time of installation of the main branch to add parallel branches in the future, further simplifying the future modification of the main branch while minimizing expenditures required for expansion. SUMMARY OF THE INVENTION [0012] A method of creating parallel sub-branch connections to a single wire power distribution system without changing the electrical characteristic of the main branch as a series line is obtained by using a DC-DC converter to connect the sub-branch to the main branch. The primary side of the DC-DC converter is connected in series with the main branch. One side of the secondary connects to the new sub-branch. The other side of the secondary is connected to seawater ground. BRIEF DESCRIPTION OF THE DRAWINGS [0013] The exact nature of this invention as well as its objects and advantages will be readily appreciated upon consideration of the following detailed description when considered in conjunction with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof and wherein: [0014] [0014]FIG. 1 is a diagrammatic illustration of a prior art series power distribution system. [0015] [0015]FIG. 2 is a diagrammatic illustration of a prior art parallel power distribution system. [0016] [0016]FIG. 3 is a conceptual drawing of a prior art series power distribution system. [0017] [0017]FIG. 4 is a conceptual drawing of a combination series and parallel power distribution system which is achievable by the present invention. [0018] [0018]FIG. 5 is a diagrammatic illustration of a preferred embodiment of a branching single wire power distribution system according to the present invention. [0019] [0019]FIG. 6 is a block diagram of a multiple branch single wire power distribution system according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0020] The conceptual layout of sensors as shown by the nodes 13 , 15 , 17 , 39 and 41 of FIG. 4 is readily achievable by utilizing the concepts of the present invention as illustrated in FIG. 5. [0021] An active power circuit 53 is inserted into the main branch 21 in series with main branch 21 by connecting to points 49 , 51 between nodes 15 and 17 , for example. The active power circuit 53 effectively converts a parallel branch connection to what appears to be a series connection to the main power source 12 which may be located on land or on a ship. The active power circuit 53 is essentially a theoretically ideal power transformer wherein the number of turns times the current flow in the primary equals the number of turns times the current flow in the secondary, operating down to DC. Since the currents and voltages are DC, a real transformer which has a limited bandwidth cannot be used. Instead, a DC-DC converter is used which simulates very closely the action of an ideal transformer operating down to DC: Although the following discussion may be in terms of an ideal transformer, it should be understood that a DC-DC converter is being used without any loss of functionality. The two primary leads on the inputs to the DC-DC converter, and the two secondary leads are the outputs. [0022] The primary side of the DC-DC converter 53 is connected into the main branch 21 in series with the nodes 13 , 15 , 17 and 45 by connecting one end of the primary 55 to insertion point 49 and the other end 57 of the primary to insertion point 51 . [0023] The secondary of the DC-DC converter 53 creates a new sub-branch series path 69 by having one end of the secondary 61 connected to a plurality of nodes 65 and 67 in series. The end of this sub-branch 69 is connected to seawater ground 71 . The other end 59 of the secondary of transformer 53 is connected to seawater ground 63 , thereby creating a new local seawater return path 73 between these two new seawater grounds 71 and 63 for the sub-branch 69 . [0024] The main power source 12 is also connected to seawater ground 43 which, together with the seawater ground 47 on the main branch 21 , creates the main seawater return path 75 for the entire system. [0025] The use of a DC-DC converter as shown in FIG. 5 to create a parallel branch can be multiplied and stacked, as desired, to create any number of branches off of the main branch or off sub-branches, the result of which is that each branch appears as a series connection in the original branch single conductor cable 21 . [0026] The branch and DC-DC converter 53 must be capable of handling the total voltage drop of the new branch and any sub-branches within the new branch as well as the series current of the original branch. The transformer does not have to regulate voltage or current. This simplifies the design of the transformer. Because it operates at a fixed duty cycle, it becomes easy to implement a zero voltage and/or zero current switching. These techniques are well-known and are advantageously used to minimize the size of the device and the noise and ripple of its operation, thereby increasing its overall efficiency. At higher voltages over 95% efficiency is obtainable. [0027] Typical input and output voltages for the branching DC-DC converter would be in the range of several hundred voltages. Typical power levels would be in the multiple hundred watts. Off-the-shelf existing DC-DC converter devices could easily be used to perform within these parameters. These devices are very small relative to the size of the electronic sensors or nodes in the system. Moreover, the costs of such converters are very low compared to overall system cost, making the addition of these branching DC-DC converters to a main branch insignificant from the cost standpoint when considered in comparison to the advantages and savings derived as the result. [0028] A typical two sub-branch multi-node distribution system is illustrated in FIG. 6. A ship or shore based power source 12 typically generates a constant current of 0.2 amp at a maximum voltage output of 450 volts. The main branch 21 connects to a series of nodes 15 , 17 , 81 and 83 , each node requiring about 10 watts of power and a 50-volt drop. Besides the main branch 21 , two sub-branches 22 and 24 are contemplated. Sub-branch 22 has an additional three nodes 65 , 67 and 77 , each of which requires 10 watts power at a 50-volt drop. Second sub-branch 24 has two nodes 87 and 89 , each node having a requirement of 10 watts of power at a 50-volt drop. All three branches, the main branch, the first sub-branch 22 and the second sub-branch 24 , are each connected respectively to low impedance sea-ground 85 , 71 and 91 . Main branch sea-ground 85 interacts with the ship or shore based power source 12 , sea-ground 43 . The sub-branch sea-ground 71 interacts with the sea ground established by branch DC-DC converter 53 . Sea-ground 91 interacts with the sea ground established by branch DC-DC converter 79 . [0029] With a total of nine nodes, each at 10 watts, a minimum of 90 watts of power is required. [0030] Branch converter 53 which facilitates the creation of the first sub-branch 22 that has three 10-watt series nodes 65 , 67 and 77 , is required at minimum to handle 30 watts of power and a total of 150 volts. Branch DC-DC converter 53 , because it is operating at near ideal conditions with one-to-one turns ratio and one-to-one voltage and current ratio, has very little power loss, is minimal in size and low in noise. [0031] The second branch DC-DC converter 79 , which facilities a second branch 24 having two series nodes 87 and 89 of 10 watts each with 50-volt drops, is required to handle a maximum of 20 watts and 100 volts. This can be easily accomplished by a converter having a one-to-one turns ratio and a one-to-one voltage current ratio with isolated input-to-output coils providing minimal size, high efficiency and low noise operation. [0032] The general rating for each branching DC-DC converter must be equal to or greater than the total branch power required by the nodes and the total branch voltage required by the nodes. [0033] The voltage conversion ratio of the branching DC-DC converter may be adjusted or set to minimize the power consumption of the total cable system with the new sub-branch cable added. Changing the voltage ratio of the branch transformer changes the reflected impedance of the added sub-branch. The voltage ratio of the transformer may then be set to optimize the efficiency of the added sub-branch. [0034] Another advantage of the present invention is that it provides the ability to add fault tolerance features to the cable system. Fault tolerance is important because cutting the main branch at any location will result in the failure of the entire line. The prior art has no way of dealing with such failures. Moreover, failure location and repair are time consuming and expensive. [0035] The branching DC-DC converter of the present invention can be utilized to isolate a sub-branch from the main branch in case of a breach in the sub-branch. The branching DC-DC converters can detect the zero current resulting from a break in the sub-branch. In response, the primary side of the converter can be shorted, allowing the main branch to continue to operate. In a system with a large number of sub-branches, this kind of fault detection and protection feature provides a high degree of fault tolerance. In a system having a number of sub-branches, a single failure may take out any single sub-branch but leave the remainder of the system functioning. [0036] In the prior art system, the current delivered by the shore power supply has an optimum value that minimizes the total system power loss. This optimum value depends on the cable resistance, which is a function of its length. In a similar fashion, the voltage conversion ratio of the branching converter may be set to minimize the power consumption of the total cable system with the new cable added. Changing the voltage ratio of the branching DC-DC converter effectively changes the reflected impedance of the added branch system. By setting the voltage ratio correctly, the efficiency of the added branch may be optimized. [0037] The voltage rating of the cable is a primary limiting factor in the power distribution system. The higher the source shore voltage compliance, the lower the current for the same total power level. The lower the current, the smaller the losses due to the cable resistance. Cable resistance may be hundreds to thousands of ohms over the length of the cable, and is fixed by the available cable. [0038] The maximum voltage is limited by the breakdown voltage rating of the cable (to the seawater). At the shore the cable is subjected to the maximum voltage. The drops, due to the node power supplies and cable resistance, lower the voltage along the length of the cable until the end of the cable is at zero voltage near the end at the sea anchor ground. The below table illustrates this concept. node voltage Sea End 0 0 1 50 2 100 3 150 4 200 5 250 6 300 7 350 8 400 9 450 10 500 11 550 12 600 13 650 14 700 15 750 16 800 17 850 18 900 19 950 20 1000 Shore End [0039] At a given maximum voltage, and a given cable resistance, there is a maximum power that can be delivered to the electronics. The optimum power delivery is when half the power is delivered to the loads, and half is lost in the cable. For a normal cable power system, efficiency is thus at a maximum of 50%. [0040] Assume that a branch line is to be installed half way down an existing cable. The available voltage at this point is approximately half the maximum shore voltage. The branching DC-DC converter step up ratio may be set to deliver the maximum voltage (as limited by the cable) to the new branch. Effectively, the new branch may be operated with a starting voltage equal to the shore voltage. This maximizes the efficiency of the new branch by maximizing the voltage. [0041] The branching DC-DC converter may also be used to improve the overall efficiency of the system past 50% and extend the maximum line length. An example is shown below. [0042] The main shoreline cable originally has 20 nodes, after which the source voltage is zero. At the 50% point, a 2:1 step up branching DC-DC converter is used to change the 500 volts back to the original source 1000 volts at the start of the first branch. The first branch could have 15 nodes, allowing a total of 26 notes, or 6 nodes more than the original capability. [0043] Adding another branch at the 50% point of the first sub-branch (again doubling the voltage) allows a total of 28 nodes. [0044] Each additional branch extends the total number of nodes by a smaller and smaller amount. If carried to an extreme with each node having a step up branching transformer, the node count and efficiency (which are directly related) could be increased by a maximum of 50%. By only using one branch, as shown above, the total number of allowable nodes was increased by 30%. The efficiency of the step DC-DC converter must be considered. In the voltage and power levels typically used, efficiencies of over 95% may be obtained.
In a single wire underwater power distribution system, parallel branching nodes are added in a manner that makes the branch connection and branch line look like a series node to the shore based power source. The primary side of a DC-DC converter functioning as an ideal transformer working down to DC is connected into the series line where a branching series line is desired. One side of the secondary creates the branched series path. The other side of the secondary goes to seawater ground, establishing a new local seawater ground.
Summarize the key points of the given document.
[ "BACKGROUND OF THE INVENTION [0001] 1.", "Field of the Invention [0002] The present invention relates generally to improvements in long underwater power distribution systems for sonar and other sensor systems, and more particularly pertains to a new and improved method and apparatus for branching a single wire underwater power distribution system.", "[0003] 2.", "Description of the Prior Art [0004] A typical prior art single wire power distribution system 11 is shown in FIG. 1 wherein power is supplied to a plurality of nodes 13 , 15 and 17 located under the ocean 25 (saltwater).", "The nodes are typically sonar or other transducer or sensor systems which require a source of power emanating from a shore or ship based power source 12 .", "These prior art power delivery systems which utilize underwater cable have been optimized for use with a single wire 21 using the seawater 25 itself as a return 23 .", "This approach minimizes cable weight because only one power wire instead of two is needed.", "Moreover, the seawater provides a lower resistance return path than an actual wire would for long runs.", "[0005] In the prior art system illustrated in FIG. 1, power flow is from a shore based power source 12 through the conductive wire 21 in the cable, through each instrument and associated electronics node 13 , 15 and 17 until the end of the cable is reached.", "At the end of the cable, a low impedance connection 19 is made to the seawater 25 .", "This particular method efficiently delivers power over any length of cable to any desired number of instruments or electronic clusters (nodes).", "Typically, the power source on shore or ship is a constant current source with voltages supplied as required by each series node.", "[0006] The disadvantage of this prior art series power delivery system is that it prevents the power conductor 21 from branching at any location along its length.", "The power source 12 located on shore or on a ship is a constant current source.", "If a branch or wire connection were to occur in the conductor 21 , the current flow in each branch would be indeterminate.", "Both branches would be connected by low impedance 19 and 33 , respectively, to the seawater for return.", "As shown in FIG. 2, branching the current path at point 27 , for example, causing a single conductor 31 branch having a single node 29 therein with a lower voltage drop to receive all the current, while the other branch 21 with two nodes 13 and 15 therein, with a higher voltage drop, would receive no current.", "Such a parallel path system would not work.", "[0007] And yet in many cases, a series only connection of electronic nodes is not optimum.", "For example, if an area of the ocean is to be populated with an evenly spaced grid of instruments such as shown in FIG. 3, a series only connection scheme would require the cable to zigzag back and forth many times between the various nodes 13 , 15 , 17 , 35 and 37 , increasing power loss and installation cost.", "[0008] A shorter total cable length would be obtained if series and parallel node connections are allowed as shown in FIG. 4. As can be seen from FIG. 4, the parallel branching connections provide for a minimum of cable length for any installation.", "However, a direct implementation of a parallel path system will not work, as discussed above.", "[0009] Furthermore, cable installation is frequently required to be modified at some later date.", "If all the nodes are in series, such modification becomes very difficult.", "New nodes may only be added at the end of a cable.", "Adding new nodes in the middle, at the beginning or off to one side of the cable is difficult to the point where it might be easier to redeploy an entirely new cable.", "This procedure is very costly since the cable itself, and its deployment in the ocean are the largest single system cost.", "[0010] The present invention method and apparatus of allowing parallel branches to be effectively placed in series with any other branch while still maintaining the basic power delivery requirements permit more flexibility and better cable usage by allowing wide branching to provide a treelike structure, more efficient coverage, i.e., less cable use over a given area is provided.", "Moreover, the cable does not have to wind back and forth to cover a certain shaped area.", "The cable length is minimized, thereby minimizing insulation costs.", "Moreover, minimizing cable length minimizes power loss as the result of the cable resistance which is proportional to the length.", "[0011] The present invention also allows relatively easy modification of the original installation.", "Simply cutting the cable at any location along the main branch, a parallel branch may be introduced.", "If desired, provisions may be made at the time of installation of the main branch to add parallel branches in the future, further simplifying the future modification of the main branch while minimizing expenditures required for expansion.", "SUMMARY OF THE INVENTION [0012] A method of creating parallel sub-branch connections to a single wire power distribution system without changing the electrical characteristic of the main branch as a series line is obtained by using a DC-DC converter to connect the sub-branch to the main branch.", "The primary side of the DC-DC converter is connected in series with the main branch.", "One side of the secondary connects to the new sub-branch.", "The other side of the secondary is connected to seawater ground.", "BRIEF DESCRIPTION OF THE DRAWINGS [0013] The exact nature of this invention as well as its objects and advantages will be readily appreciated upon consideration of the following detailed description when considered in conjunction with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof and wherein: [0014] [0014 ]FIG. 1 is a diagrammatic illustration of a prior art series power distribution system.", "[0015] [0015 ]FIG. 2 is a diagrammatic illustration of a prior art parallel power distribution system.", "[0016] [0016 ]FIG. 3 is a conceptual drawing of a prior art series power distribution system.", "[0017] [0017 ]FIG. 4 is a conceptual drawing of a combination series and parallel power distribution system which is achievable by the present invention.", "[0018] [0018 ]FIG. 5 is a diagrammatic illustration of a preferred embodiment of a branching single wire power distribution system according to the present invention.", "[0019] [0019 ]FIG. 6 is a block diagram of a multiple branch single wire power distribution system according to the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0020] The conceptual layout of sensors as shown by the nodes 13 , 15 , 17 , 39 and 41 of FIG. 4 is readily achievable by utilizing the concepts of the present invention as illustrated in FIG. 5. [0021] An active power circuit 53 is inserted into the main branch 21 in series with main branch 21 by connecting to points 49 , 51 between nodes 15 and 17 , for example.", "The active power circuit 53 effectively converts a parallel branch connection to what appears to be a series connection to the main power source 12 which may be located on land or on a ship.", "The active power circuit 53 is essentially a theoretically ideal power transformer wherein the number of turns times the current flow in the primary equals the number of turns times the current flow in the secondary, operating down to DC.", "Since the currents and voltages are DC, a real transformer which has a limited bandwidth cannot be used.", "Instead, a DC-DC converter is used which simulates very closely the action of an ideal transformer operating down to DC: Although the following discussion may be in terms of an ideal transformer, it should be understood that a DC-DC converter is being used without any loss of functionality.", "The two primary leads on the inputs to the DC-DC converter, and the two secondary leads are the outputs.", "[0022] The primary side of the DC-DC converter 53 is connected into the main branch 21 in series with the nodes 13 , 15 , 17 and 45 by connecting one end of the primary 55 to insertion point 49 and the other end 57 of the primary to insertion point 51 .", "[0023] The secondary of the DC-DC converter 53 creates a new sub-branch series path 69 by having one end of the secondary 61 connected to a plurality of nodes 65 and 67 in series.", "The end of this sub-branch 69 is connected to seawater ground 71 .", "The other end 59 of the secondary of transformer 53 is connected to seawater ground 63 , thereby creating a new local seawater return path 73 between these two new seawater grounds 71 and 63 for the sub-branch 69 .", "[0024] The main power source 12 is also connected to seawater ground 43 which, together with the seawater ground 47 on the main branch 21 , creates the main seawater return path 75 for the entire system.", "[0025] The use of a DC-DC converter as shown in FIG. 5 to create a parallel branch can be multiplied and stacked, as desired, to create any number of branches off of the main branch or off sub-branches, the result of which is that each branch appears as a series connection in the original branch single conductor cable 21 .", "[0026] The branch and DC-DC converter 53 must be capable of handling the total voltage drop of the new branch and any sub-branches within the new branch as well as the series current of the original branch.", "The transformer does not have to regulate voltage or current.", "This simplifies the design of the transformer.", "Because it operates at a fixed duty cycle, it becomes easy to implement a zero voltage and/or zero current switching.", "These techniques are well-known and are advantageously used to minimize the size of the device and the noise and ripple of its operation, thereby increasing its overall efficiency.", "At higher voltages over 95% efficiency is obtainable.", "[0027] Typical input and output voltages for the branching DC-DC converter would be in the range of several hundred voltages.", "Typical power levels would be in the multiple hundred watts.", "Off-the-shelf existing DC-DC converter devices could easily be used to perform within these parameters.", "These devices are very small relative to the size of the electronic sensors or nodes in the system.", "Moreover, the costs of such converters are very low compared to overall system cost, making the addition of these branching DC-DC converters to a main branch insignificant from the cost standpoint when considered in comparison to the advantages and savings derived as the result.", "[0028] A typical two sub-branch multi-node distribution system is illustrated in FIG. 6. A ship or shore based power source 12 typically generates a constant current of 0.2 amp at a maximum voltage output of 450 volts.", "The main branch 21 connects to a series of nodes 15 , 17 , 81 and 83 , each node requiring about 10 watts of power and a 50-volt drop.", "Besides the main branch 21 , two sub-branches 22 and 24 are contemplated.", "Sub-branch 22 has an additional three nodes 65 , 67 and 77 , each of which requires 10 watts power at a 50-volt drop.", "Second sub-branch 24 has two nodes 87 and 89 , each node having a requirement of 10 watts of power at a 50-volt drop.", "All three branches, the main branch, the first sub-branch 22 and the second sub-branch 24 , are each connected respectively to low impedance sea-ground 85 , 71 and 91 .", "Main branch sea-ground 85 interacts with the ship or shore based power source 12 , sea-ground 43 .", "The sub-branch sea-ground 71 interacts with the sea ground established by branch DC-DC converter 53 .", "Sea-ground 91 interacts with the sea ground established by branch DC-DC converter 79 .", "[0029] With a total of nine nodes, each at 10 watts, a minimum of 90 watts of power is required.", "[0030] Branch converter 53 which facilitates the creation of the first sub-branch 22 that has three 10-watt series nodes 65 , 67 and 77 , is required at minimum to handle 30 watts of power and a total of 150 volts.", "Branch DC-DC converter 53 , because it is operating at near ideal conditions with one-to-one turns ratio and one-to-one voltage and current ratio, has very little power loss, is minimal in size and low in noise.", "[0031] The second branch DC-DC converter 79 , which facilities a second branch 24 having two series nodes 87 and 89 of 10 watts each with 50-volt drops, is required to handle a maximum of 20 watts and 100 volts.", "This can be easily accomplished by a converter having a one-to-one turns ratio and a one-to-one voltage current ratio with isolated input-to-output coils providing minimal size, high efficiency and low noise operation.", "[0032] The general rating for each branching DC-DC converter must be equal to or greater than the total branch power required by the nodes and the total branch voltage required by the nodes.", "[0033] The voltage conversion ratio of the branching DC-DC converter may be adjusted or set to minimize the power consumption of the total cable system with the new sub-branch cable added.", "Changing the voltage ratio of the branch transformer changes the reflected impedance of the added sub-branch.", "The voltage ratio of the transformer may then be set to optimize the efficiency of the added sub-branch.", "[0034] Another advantage of the present invention is that it provides the ability to add fault tolerance features to the cable system.", "Fault tolerance is important because cutting the main branch at any location will result in the failure of the entire line.", "The prior art has no way of dealing with such failures.", "Moreover, failure location and repair are time consuming and expensive.", "[0035] The branching DC-DC converter of the present invention can be utilized to isolate a sub-branch from the main branch in case of a breach in the sub-branch.", "The branching DC-DC converters can detect the zero current resulting from a break in the sub-branch.", "In response, the primary side of the converter can be shorted, allowing the main branch to continue to operate.", "In a system with a large number of sub-branches, this kind of fault detection and protection feature provides a high degree of fault tolerance.", "In a system having a number of sub-branches, a single failure may take out any single sub-branch but leave the remainder of the system functioning.", "[0036] In the prior art system, the current delivered by the shore power supply has an optimum value that minimizes the total system power loss.", "This optimum value depends on the cable resistance, which is a function of its length.", "In a similar fashion, the voltage conversion ratio of the branching converter may be set to minimize the power consumption of the total cable system with the new cable added.", "Changing the voltage ratio of the branching DC-DC converter effectively changes the reflected impedance of the added branch system.", "By setting the voltage ratio correctly, the efficiency of the added branch may be optimized.", "[0037] The voltage rating of the cable is a primary limiting factor in the power distribution system.", "The higher the source shore voltage compliance, the lower the current for the same total power level.", "The lower the current, the smaller the losses due to the cable resistance.", "Cable resistance may be hundreds to thousands of ohms over the length of the cable, and is fixed by the available cable.", "[0038] The maximum voltage is limited by the breakdown voltage rating of the cable (to the seawater).", "At the shore the cable is subjected to the maximum voltage.", "The drops, due to the node power supplies and cable resistance, lower the voltage along the length of the cable until the end of the cable is at zero voltage near the end at the sea anchor ground.", "The below table illustrates this concept.", "node voltage Sea End 0 0 1 50 2 100 3 150 4 200 5 250 6 300 7 350 8 400 9 450 10 500 11 550 12 600 13 650 14 700 15 750 16 800 17 850 18 900 19 950 20 1000 Shore End [0039] At a given maximum voltage, and a given cable resistance, there is a maximum power that can be delivered to the electronics.", "The optimum power delivery is when half the power is delivered to the loads, and half is lost in the cable.", "For a normal cable power system, efficiency is thus at a maximum of 50%.", "[0040] Assume that a branch line is to be installed half way down an existing cable.", "The available voltage at this point is approximately half the maximum shore voltage.", "The branching DC-DC converter step up ratio may be set to deliver the maximum voltage (as limited by the cable) to the new branch.", "Effectively, the new branch may be operated with a starting voltage equal to the shore voltage.", "This maximizes the efficiency of the new branch by maximizing the voltage.", "[0041] The branching DC-DC converter may also be used to improve the overall efficiency of the system past 50% and extend the maximum line length.", "An example is shown below.", "[0042] The main shoreline cable originally has 20 nodes, after which the source voltage is zero.", "At the 50% point, a 2:1 step up branching DC-DC converter is used to change the 500 volts back to the original source 1000 volts at the start of the first branch.", "The first branch could have 15 nodes, allowing a total of 26 notes, or 6 nodes more than the original capability.", "[0043] Adding another branch at the 50% point of the first sub-branch (again doubling the voltage) allows a total of 28 nodes.", "[0044] Each additional branch extends the total number of nodes by a smaller and smaller amount.", "If carried to an extreme with each node having a step up branching transformer, the node count and efficiency (which are directly related) could be increased by a maximum of 50%.", "By only using one branch, as shown above, the total number of allowable nodes was increased by 30%.", "The efficiency of the step DC-DC converter must be considered.", "In the voltage and power levels typically used, efficiencies of over 95% may be obtained." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This is a continuation of International Application No. PCT/US02/37326, filed on Nov. 21, 2002, which, in turn, relies upon and claims benefit of the filing date of U.S. Provisional Patent Application No. 60/337,171, filed Dec. 10, 2001, the contents of both which are incorporated herein by reference in their entireties. The present application is related to co-pending applications entitled “Device and Method For Coupling Two Circuit Components Which Have Different Impedances”, PCT Application US01/40073, filed Feb. 9, 2001, now U.S. Pat. No. 6,700,458, and “Method and Device for Attenuating Harmonics in Semiconductor Plasma Processing Systems”, PCT Application US01/04135, filed Feb. 9, 2001, now U.S. Patent Publication No. US-2003-0057844. Each of these applications is herein incorporated by reference in its entirety. BACKGROUND OF THE INVENTION In the past, various techniques have been proposed for selective attenuation of harmonic frequencies created in plasma processing systems. These techniques utilize either a low-pass filter or a trap circuit. For example, U.S. Pat. No. 5,302,882 entitled “LOW-PASS FILTER FOR PLASMA DISCHARGE” discloses such techniques. In the plasma processing industry, capacitively coupled plasma sources are widely used for dry etching and plasma enhanced chemical deposition. Dry etching is a process for removing a layer of material from a wafer surface. This removal is a result of combined mechanical and chemical effects of high-energy plasma ions striking the substrate surface In plasma enhanced chemical deposition, a layer of a material is deposited on the substrate surface. This material is introduced into the plasma either by sputtering a target made of the material or by supplying a gas which contains the material or from which the material is produced by a chemical reaction. The material may be ionized by the plasma and can then be attracted to the substrate by an electric field. Plasma processing is commonly used in the semiconductor fabrication industry. The trend in the semiconductor fabrication industry has been toward integrated circuits having smaller elemental features. As a result, etch and deposition rate uniformity over the wafer surface has become more important, particularly when a layer is being etched or deposited according to a pattern. At the same time, recent developments in plasma source technology have led to the increased use of very high frequency RF excitation, e.g., from 60 to 300 MHz, and possibly even higher, to initiate and sustain the plasma. The use of these very high excitation frequencies provides a benefit in the form of increased power coupling to the plasma, and thus excitation efficiency, that is likely caused by an increase of plasma electron temperature. This increase of RF power coupling affects the plasma density and the harmonic generation in the plasma. However, maintaining high etching and deposition rate uniformity levels at these very high excitation frequencies and with strong harmonics present has proven to be a difficult feat, for a number of reasons. For example, as the plasma RF excitation frequency is increased, the wavelength of the RF wave decreases. Thus, RF electromagnetic field spatial variations are more pronounced at these higher frequencies and this adversely affects process uniformity. In addition, another trend in the industry is to process larger wafers, 300 mm diameter wafer technology presently being implemented. Of course, as wafer diameter increases, the wavelength-to-wafer-diameter ratio decreases. Plasma acts as a nonlinear RF circuit element and thus acts as a source of harmonics of the fundamental excitation frequency. These harmonics, due to their higher frequencies, have an even higher power coupling efficiency to the plasma than the fundamental. Therefore, harmonics, even if present at very low power levels, can significantly affect process uniformity due to their very unfavorable wavelength-to-wafer-diameter ratio. Since harmonics of the RF fundamental excitation frequency have comparatively short wavelengths, they are far more likely to set up resonances in various places in the process chamber, RF transmission lines, cavities, etc., since their half-wavelengths are comparable to the dimensions of these places. The situation is further worsened by the use of components made of high permittivity (ε) and/or permeability (μ) materials, or by the presence of RF transmission structural features that have significant series inductance (L) and/or shunt capacitance (C). Both of these effects reduce the wavelength of the propagating electromagnetic wave in a structure, the former by directly changing the wave propagation velocity, the latter by creating a “slow-wave” structure. This wavelength reduction allows harmonics to resonate in places where they normally would not. It can thus be seen that reduction of the power content of the harmonics of the RF excitation frequency would improve etch or deposition uniformity. BRIEF SUMMARY OF THE INVENTION It is a primary object of the present invention to control the power levels of harmonics of the fundamental frequency of the RF excitation power in plasma processing systems. The above and other objects are achieved, according to the present invention, by a plasma processing system composed of a chamber enclosing a plasma region, a source of RF power having a fundamental frequency and means for transmitting the RF power from the source into the plasma region for establishing an RF electromagnetic field which interacts with a gas in the plasma region to create a plasma; and energy. Energy controlling members that include RF absorbing loads are disposed in energy-receiving communication with the plasma region. The RF absorbing loads have a frequency dependent attenuation characteristic such that the RF absorbing loads remove electrical energy appearing in the plasma at frequencies higher than the fundamental frequency more strongly than energy at the fundamental frequency. Objects according to the invention are also achieved by method for maintaining a plasma in a plasma region, which method includes supplying RF power at a fundamental frequency to the plasma region together with a gas in order to create an RF electromagnetic field which interacts with the gas to create a plasma that contains electromagnetic energy components at frequencies that are harmonics of the fundamental frequency, and removing those components from the plasma, wherein the step of removing is carried out by placing RF absorbing loads in energy-receiving communication with the plasma, the loads having a frequency dependent attenuation characteristic such that the loads remove electrical energy appearing in the plasma at frequencies higher than the fundamental frequency more strongly than energy at the fundamental frequency. BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows a simplified block diagram of a plasma processing system in accordance with a preferred embodiment of the present invention; FIG. 2 a shows a simplified block diagram of a trapping assembly in accordance with a preferred embodiment of the present invention; FIG. 2 b is a cross-sectional view of a trapping assembly in accordance with a preferred embodiment of the present invention; FIG. 3 illustrates a simplified schematic representation of a frequency selective trap element in accordance with a preferred embodiment of the present invention; FIG. 4 shows an alternate embodiment of the present invention in which a trapping assembly is coupled between a match network and a lower electrode; and FIG. 5 shows an alternate embodiment of the present invention in which a trapping assembly comprising a plurality of transmission lines is coupled between a match network and an upper electrode. DETAILED DESCRIPTION OF THE EMBODIMENTS A plasma processing system of the type to which this invention is applied includes a chamber which encloses a plasma region filled with an ionizable gas and into which RF electromagnetic energy is coupled. The energy interacts with the gas to initiate and sustain a plasma. According to the invention, one or more components are provided to control the energy contained in harmonics of the fundamental frequency of the RF energy coupled into and out of the plasma. This harmonic attenuation can take place wherever a suitable impedance-matched coupling structure is present, or can be provided to couple the harmonic power out of the plasma. In one embodiment, frequency selective trap elements are provided, that selectively absorb power associated with certain harmonics while not affecting the others. Desirably, resistive loads are coupled to the transmission line, which delivers the RF electromagnetic energy to the plasma. All harmonics are generated at impedances different from the impedance of the fundamental frequency, and every harmonic has a different impedance at which it can be attenuated. In order to be effective at trapping different harmonics, the impedance of the trapping assembly must be variable. So not only is the trap frequency selective, but its input impedance is also variable and matched to the impedance of the harmonics that need to be controlled at that frequency. As the input of the matching network is changed, the frequency of the trapping assembly is also changed. As the plasma density or plasma species changes, the impedance of the harmonics will also change. Therefore, the trapping networks and the matching networks have to be tunable. The design and implementation of a plurality of resistive loads and associated trapping networks that are under automatic control allows precise tailoring of the harmonic content in the plasma. The presence of matching networks is implicitly necessary because of the need to have some physical connection to the electrode so that electrical power can be applied. Thus, a plurality of resistive loads and associated networks are under automatic control so as to allow precise tailoring of the harmonic content of the plasma. This invention further includes a method of using the trapping network as a plasma harmonic detector to feed back the variations of the harmonics to the controller controlling the trapping network. The plasma harmonic detector detects the spectral content and spatial variations of the RF field in the plasma. The feedback signals from the plasma harmonic detector will adjust the matching networks to minimize a particular function. That particular function can be the spectral and spatial variations of certain harmonics at certain frequency. There is a multiplicity of the small matching networks around the electrode. By using the plasma harmonics detector with a specific algorithm, each of the matching networks can be tuned to achieve the best plasma uniformity results. This invention still further includes a method of using the apparatus as a process reliability detector by measuring the voltage across the resistive elements in the trap. By monitoring the amount of the power dissipated by the resistive element, a very precise evaluation of the plasma process conditions is made. Measuring the amount of power the plasma available in its harmonic range makes a very subtle and precise measurement of the condition of the plasma. FIG. 1 shows a simplified block diagram of a plasma processing system in accordance with a preferred embodiment of the present invention. Plasma processing system 100 comprises plasma excitation RF source 102 that supplies RF power at a fundamental frequency and a match network 104 . Trapping assembly 106 is coupled between match network 104 and an upper electrode 108 , which is located at the top of a plasma chamber 110 . Plasma chamber 110 encloses a plasma region in which plasma 112 will be initiated and maintained. A wafer chuck 114 is located at the bottom of the plasma region and is connected to a second RF source 116 via a second match network 118 . Electrodes 108 , 114 and sources 102 , 116 form a capacitively coupled RF plasma source that is used for performing an etch or deposition operation on a wafer mounted on chuck 114 . Source 116 acts primarily to impose a DC self-bias on wafer chuck 114 , which self-bias acts to attract ions to the surface of the wafer mounted on chuck 114 . Trapping assembly 106 is located on the main RF feed line to electrode 108 . Controller 130 is coupled to trapping assembly 106 . Controller 130 receives measurement data from trapping assembly 106 and sends control data to trapping assembly 106 . Controller 130 processes a portion of the measurement data to create control data. For example, the controller can perform a fast Fourier transform (FFT). In addition, controller 130 is used to control system operations and monitor the process. Controller 130 can comprise a computer or embedded processor, such as a digital signal processor (DSP). These types of processors are known to those skilled in the art. Plasma 112 can be excited and maintained by RF electromagnetic wave energy at the fundamental RF frequency that is passed to upper electrode 108 and plasma 112 by match network 104 and trapping assembly 106 . Trapping assembly 106 comprises a transmission line that is essentially transparent to RF electromagnetic wave energy at that frequency. Plasma 112 , in turn, converts some of the energy that it receives at the fundamental frequency into harmonics, and these are coupled back into upper electrode 108 and trapping assembly 106 . Energy at harmonic frequencies is strongly attenuated in the resistive loads of trapping assembly 106 , and a significant amount of this energy is dissipated in the form of heat along the length of trapping assembly 106 . The reduction of power at harmonic frequencies results in better electric field uniformity at and below upper electrode 108 , and thus better etch and deposition uniformity. FIGS. 2 a and 2 b show a simplified block diagram of a trapping assembly in accordance with a preferred embodiment of the present invention. Trapping assembly 106 comprises transmission line 170 and a plurality of frequency selective trap elements 172 . Transmission line 170 has a frustoconical coaxial geometry. This geometry primarily serves to reduce reflection points between match network 104 and upper electrode 108 . Preferably, transmission line 170 has a constant characteristic impedance, which also helps to reduce reflections. By making the ratio of the outer diameter to the inner diameter of transmission line 170 constant, a constant characteristic impedance is maintained. Alternately, the impedance of transmission line 170 can vary along its length. Transmission line 170 comprises inner conductor 174 and outer conductor 176 . Transmission line 170 can comprise any suitable configuration including a coaxial line, microstrip, or strip-line. Outer conductor 176 comprises a conically shaped sheet of low-loss conducting material such as copper, silver-plated copper, aluminum, or silver-plated aluminum. Outer conductor 176 is coupled to element 199 . Element 199 is part of the process chamber wall and supports trapping assembly 106 . Outer conductor 176 is coupled to ground via element 199 . Inner conductor 174 comprises a conically shaped block of low-loss conducting material such as copper, silver-plated copper, aluminum, or silver-plated aluminum. Inner conductor 174 is coupled to cooling plate 120 , and cooling plate 120 is coupled to electrode 108 . Inner conductor 174 comprises at least one cooling channel, as described below. Frequency selective trap elements 172 are electrically coupled to both inner conductor 174 and outer conductor 176 . Frequency selective trap elements 172 on the transmission line are tuned to harmonic frequencies to selectively monitor and control the harmonic content of the plasma. Frequency selective trap elements 172 are arranged in the space outside the outer conductor 176 and are in electrical contact with the inner conductor 174 through an opening in the outer conductor 176 . Alternately, frequency selective trap elements 172 can be positioned between the inner conductor 174 and the outer conductor 176 . Conductors 174 , 176 and the above-mentioned cooling channel are all axially symmetrical in this embodiment although they do not necessarily need to be. Outer conductor 176 constitutes a RF ground return terminal. The usual two match network output terminals are connected to inner conductor 174 and outer conductor 176 , respectively. This is achieved by mounting a match network output capacitor 128 directly on top of the inner conductor 174 . Outer conductor 176 is connected within the enclosure of match network 104 , which enclosure serves as a ground conductor. Upper electrode 108 is of the shower head type, provided with a plurality of passages (not shown) for delivery of process gas to the plasma region from a plenum 129 enclosed between electrode 108 and cooling plate 120 . The plenum is supplied with process gas by a gas feed line 132 . Gas feed line 132 is connected to a process gas source and extends along the vertical axis of the frustoconic outline of transmission line 170 . The lower surface of electrode 108 , the surface which faces the plasma region, is covered with a shower-head plate 136 , i.e., a plate provided with gas passages aligned with passages. Plate 136 may be made of material compatible with the chamber process, e.g., doped silicon. Plate 136 acts to prevent sputtering of material from electrode 108 . In addition, silicon plate 136 is made of a material compatible with the chamber process, to prevent contamination, and as such acts to separate the plasma from the lower surface of electrode 108 . This is particularly advantageous when electrode 108 contains a material that is not chemically compatible with the process. An alumina dielectric ring insulator 198 serves to extend coax transmission line below trapping assembly 106 and around cooling plate 120 and electrode 108 . The part of the transmission line constituted by insulator 198 does not absorb any RF and acts as a connection between the plasma and the trapping assembly 106 . Insulator 198 constitutes the dielectric of a coax line whose walls are metallic parts provided by cooling plate 120 , electrode 108 , and the chamber structure, a portion of which is shown as element 199 . A quartz shield ring 138 is attached around plate 136 and below electrode 108 . Quartz shield ring 138 is provided to cover the screws that are used to attach silicon plate 136 to electrode 108 , thereby isolating those screws from the plasma environment to prevent process contamination. Electrode 108 , plate 136 and ring 138 are all attached to, and supported by, cooling plate 120 , which is in turn supported by insulator ring 198 , the latter itself being supported by the chamber wall structure 199 . Cooling of the inner conductor 174 is performed through a coolant fluid circulated through a cooling channel 140 formed in inner conductor 174 . Cooling channel 140 is annular in shape and communicates with a coolant fluid source and a heat exchange element via inlet and outlet cooling lines 142 . As noted earlier herein, cooling channel 140 is axially symmetrical. The coolant fluid in channel 140 also acts to cool upper electrode 108 . Match network 104 (details of which are not shown) is mounted on top of trapping assembly 106 , and all cooling and gas feed connections are made within its RF enclosure. Match network 104 can be constructed according to principles well known in the art. FIG. 3 illustrates a simplified schematic representation of a frequency selective trap element in accordance with a preferred embodiment of the present invention. In the illustrated embodiment, frequency selective trap element 172 comprises input port 310 connected to inner conductor 174 , output port 312 connected to outer conductor 176 , control port 314 , transmission line 316 , coupling capacitor 318 , match network 320 , resistive load 322 , and probe 330 . In the illustrated embodiment, control port 314 is coupled to match network 320 and probe 330 . Alternately, other configurations can be envisioned. Control port 314 is coupled to controller 130 and comprises both control and sensor functions. Control port 314 is configured using at least one shielded cable. Resistive load 322 comprises at least one high power resistor that is mounted on a thermally conductive surface, such as the outer conductor. Match network 320 comprises a plurality of narrow band components, and wideband components. For example, variable capacitors and variable inductors can be used, or at higher frequencies, stub tuners and hybrid networks can be used. Match network 320 allows each frequency selective trap element 172 to be tuned to a particular harmonic frequency. For example, a control voltage can be provided to at least one varactor diode or at least one variable capacitor. Matching network techniques are known to those skilled in the art. In addition, match network 320 can provide measurement data from load resistor 322 and/or from match network 320 to controller 130 . For example, measurement data can include voltage, current, and/or power data. Desirably, probe 330 provides measurement data that includes voltage and current information from transmission line 316 . Alternately, measurement data can include magnitude and phase information. Controller 130 uses the measurement data to determine which frequency components are present and sends control data to match network 320 . Desirably, match network 320 is tuned to the proper frequency, and the desired signal level is achieved at load resistor 322 . Alternately, the desired signal level can be achieved at match network 320 or probe 330 . One or more frequency selective trap element 172 is used for each harmonic signal being controlled. Controller 130 is coupled to each one of the frequency selective trap elements 172 and tunes the match networks in all of the frequency selective trap elements 172 in the trapping assembly to achieve the proper harmonic profile. Desirably, proper harmonic profiles can be determined using experimental data from processes providing uniform etch rates. For example, historical data correlating process results to harmonic profiles can be used to produce algorithms for controller 130 . Harmonic profiles include fundamental and harmonic signal information. Also, controller 130 controls the operating levels of the RF sources used to generate the plasma. Controller 130 can adjust these operating levels to control the power delivered to the plasma at the fundamental frequency and to a lesser degree the harmonic levels. For example, controller 130 may have to increase the power delivered to the plasma at the fundamental frequency in order to maintain the desired plasma density. In addition, controller 130 controls the operating frequencies of the RF sources used to generate the plasma and can tune the operating frequencies to further control the harmonic profile. Those skilled in the art will also recognize that controller 130 controls match networks 104 and 108 ( FIG. 1 ) and can use these system level match networks to control the harmonic profile. By controlling the fundamental level and the harmonic levels, controller 130 generates a high density, uniform plasma. FIG. 4 shows an alternate embodiment of the present invention in which a trapping assembly is coupled between a match network and a lower electrode. Lower electrode comprises a wafer chuck for supporting wafer 470 while a plasma process is performed. RF power is supplied to match network 418 by power source 416 . Trapping assembly 406 comprises transmission line 480 and a plurality of frequency selective trap elements 472 . Transmission line 480 is a coaxial transmission line comprising inner conductor 474 , outer conductor 476 , and dielectric layer 478 . At least one frequency selective trap element 472 is coupled between and in electrical contact with conductors 474 and 476 . Frequency selective trap elements 472 selectively controls the amount of energy which arises within the plasma at frequencies that are harmonics of the fundamental frequency produced by power source 416 and also all other frequencies in the chamber associated with upper electrode plasma excitation (e.g., fundamental and harmonics of upper electrode), and which is conducted to trapping assembly 406 via chuck 414 , after being coupled into chuck 414 from the plasma. FIG. 5 shows an alternate embodiment of the present invention in which a trapping assembly comprising a plurality of transmission lines is coupled between a match network and an upper electrode. Trapping assembly 506 comprises a plurality of transmission lines 570 and a plurality of frequency selective trap elements 572 . Desirably, at least one frequency selective trap element 572 is coupled to each transmission line 570 . Transmission line 570 comprises first conductor 574 , second conductor 576 , and dielectric 578 . Transmission lines 570 can comprise any suitable configuration including coaxial line, microstrip, or strip-line. Transmission lines 570 can have different physical characteristics. One or more frequency selective trap elements can be tuned to selectively control the amount of energy, which arises within the plasma chamber at frequencies that are harmonics of the fundamental frequency. In addition, when multiple transmission lines are used in a trapping assembly, the transmission lines can be designed to make the trapping assembly more efficient. Alternately, the transmission lines can also comprise an absorber material, which can be used to further control the harmonic levels. While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
A system and method for maintaining a plasma in a plasma region by supplying RF power at a fundamental frequency to the plasma region together with a gas in order to create an RF electromagnetic field which interacts with the gas to create a plasma that contains electromagnetic energy components at frequencies that are harmonics of the fundamental frequency. The components at frequencies that are harmonics of the fundamental frequency are reduced by placing RF energy absorbing resistive loads in energy receiving communication with the plasma, the resistive loads having a frequency dependent attenuation characteristic such that the resistive loads attenuate electrical energy at frequencies higher than the fundamental frequency more strongly than energy at the fundamental frequency.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This is a continuation of International Application No. PCT/US02/37326, filed on Nov. 21, 2002, which, in turn, relies upon and claims benefit of the filing date of U.S. Provisional Patent Application No. 60/337,171, filed Dec. 10, 2001, the contents of both which are incorporated herein by reference in their entireties.", "The present application is related to co-pending applications entitled “Device and Method For Coupling Two Circuit Components Which Have Different Impedances”, PCT Application US01/40073, filed Feb. 9, 2001, now U.S. Pat. No. 6,700,458, and “Method and Device for Attenuating Harmonics in Semiconductor Plasma Processing Systems”, PCT Application US01/04135, filed Feb. 9, 2001, now U.S. Patent Publication No. US-2003-0057844.", "Each of these applications is herein incorporated by reference in its entirety.", "BACKGROUND OF THE INVENTION In the past, various techniques have been proposed for selective attenuation of harmonic frequencies created in plasma processing systems.", "These techniques utilize either a low-pass filter or a trap circuit.", "For example, U.S. Pat. No. 5,302,882 entitled “LOW-PASS FILTER FOR PLASMA DISCHARGE”", "discloses such techniques.", "In the plasma processing industry, capacitively coupled plasma sources are widely used for dry etching and plasma enhanced chemical deposition.", "Dry etching is a process for removing a layer of material from a wafer surface.", "This removal is a result of combined mechanical and chemical effects of high-energy plasma ions striking the substrate surface In plasma enhanced chemical deposition, a layer of a material is deposited on the substrate surface.", "This material is introduced into the plasma either by sputtering a target made of the material or by supplying a gas which contains the material or from which the material is produced by a chemical reaction.", "The material may be ionized by the plasma and can then be attracted to the substrate by an electric field.", "Plasma processing is commonly used in the semiconductor fabrication industry.", "The trend in the semiconductor fabrication industry has been toward integrated circuits having smaller elemental features.", "As a result, etch and deposition rate uniformity over the wafer surface has become more important, particularly when a layer is being etched or deposited according to a pattern.", "At the same time, recent developments in plasma source technology have led to the increased use of very high frequency RF excitation, e.g., from 60 to 300 MHz, and possibly even higher, to initiate and sustain the plasma.", "The use of these very high excitation frequencies provides a benefit in the form of increased power coupling to the plasma, and thus excitation efficiency, that is likely caused by an increase of plasma electron temperature.", "This increase of RF power coupling affects the plasma density and the harmonic generation in the plasma.", "However, maintaining high etching and deposition rate uniformity levels at these very high excitation frequencies and with strong harmonics present has proven to be a difficult feat, for a number of reasons.", "For example, as the plasma RF excitation frequency is increased, the wavelength of the RF wave decreases.", "Thus, RF electromagnetic field spatial variations are more pronounced at these higher frequencies and this adversely affects process uniformity.", "In addition, another trend in the industry is to process larger wafers, 300 mm diameter wafer technology presently being implemented.", "Of course, as wafer diameter increases, the wavelength-to-wafer-diameter ratio decreases.", "Plasma acts as a nonlinear RF circuit element and thus acts as a source of harmonics of the fundamental excitation frequency.", "These harmonics, due to their higher frequencies, have an even higher power coupling efficiency to the plasma than the fundamental.", "Therefore, harmonics, even if present at very low power levels, can significantly affect process uniformity due to their very unfavorable wavelength-to-wafer-diameter ratio.", "Since harmonics of the RF fundamental excitation frequency have comparatively short wavelengths, they are far more likely to set up resonances in various places in the process chamber, RF transmission lines, cavities, etc.", ", since their half-wavelengths are comparable to the dimensions of these places.", "The situation is further worsened by the use of components made of high permittivity (ε) and/or permeability (μ) materials, or by the presence of RF transmission structural features that have significant series inductance (L) and/or shunt capacitance (C).", "Both of these effects reduce the wavelength of the propagating electromagnetic wave in a structure, the former by directly changing the wave propagation velocity, the latter by creating a “slow-wave”", "structure.", "This wavelength reduction allows harmonics to resonate in places where they normally would not.", "It can thus be seen that reduction of the power content of the harmonics of the RF excitation frequency would improve etch or deposition uniformity.", "BRIEF SUMMARY OF THE INVENTION It is a primary object of the present invention to control the power levels of harmonics of the fundamental frequency of the RF excitation power in plasma processing systems.", "The above and other objects are achieved, according to the present invention, by a plasma processing system composed of a chamber enclosing a plasma region, a source of RF power having a fundamental frequency and means for transmitting the RF power from the source into the plasma region for establishing an RF electromagnetic field which interacts with a gas in the plasma region to create a plasma;", "and energy.", "Energy controlling members that include RF absorbing loads are disposed in energy-receiving communication with the plasma region.", "The RF absorbing loads have a frequency dependent attenuation characteristic such that the RF absorbing loads remove electrical energy appearing in the plasma at frequencies higher than the fundamental frequency more strongly than energy at the fundamental frequency.", "Objects according to the invention are also achieved by method for maintaining a plasma in a plasma region, which method includes supplying RF power at a fundamental frequency to the plasma region together with a gas in order to create an RF electromagnetic field which interacts with the gas to create a plasma that contains electromagnetic energy components at frequencies that are harmonics of the fundamental frequency, and removing those components from the plasma, wherein the step of removing is carried out by placing RF absorbing loads in energy-receiving communication with the plasma, the loads having a frequency dependent attenuation characteristic such that the loads remove electrical energy appearing in the plasma at frequencies higher than the fundamental frequency more strongly than energy at the fundamental frequency.", "BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows a simplified block diagram of a plasma processing system in accordance with a preferred embodiment of the present invention;", "FIG. 2 a shows a simplified block diagram of a trapping assembly in accordance with a preferred embodiment of the present invention;", "FIG. 2 b is a cross-sectional view of a trapping assembly in accordance with a preferred embodiment of the present invention;", "FIG. 3 illustrates a simplified schematic representation of a frequency selective trap element in accordance with a preferred embodiment of the present invention;", "FIG. 4 shows an alternate embodiment of the present invention in which a trapping assembly is coupled between a match network and a lower electrode;", "and FIG. 5 shows an alternate embodiment of the present invention in which a trapping assembly comprising a plurality of transmission lines is coupled between a match network and an upper electrode.", "DETAILED DESCRIPTION OF THE EMBODIMENTS A plasma processing system of the type to which this invention is applied includes a chamber which encloses a plasma region filled with an ionizable gas and into which RF electromagnetic energy is coupled.", "The energy interacts with the gas to initiate and sustain a plasma.", "According to the invention, one or more components are provided to control the energy contained in harmonics of the fundamental frequency of the RF energy coupled into and out of the plasma.", "This harmonic attenuation can take place wherever a suitable impedance-matched coupling structure is present, or can be provided to couple the harmonic power out of the plasma.", "In one embodiment, frequency selective trap elements are provided, that selectively absorb power associated with certain harmonics while not affecting the others.", "Desirably, resistive loads are coupled to the transmission line, which delivers the RF electromagnetic energy to the plasma.", "All harmonics are generated at impedances different from the impedance of the fundamental frequency, and every harmonic has a different impedance at which it can be attenuated.", "In order to be effective at trapping different harmonics, the impedance of the trapping assembly must be variable.", "So not only is the trap frequency selective, but its input impedance is also variable and matched to the impedance of the harmonics that need to be controlled at that frequency.", "As the input of the matching network is changed, the frequency of the trapping assembly is also changed.", "As the plasma density or plasma species changes, the impedance of the harmonics will also change.", "Therefore, the trapping networks and the matching networks have to be tunable.", "The design and implementation of a plurality of resistive loads and associated trapping networks that are under automatic control allows precise tailoring of the harmonic content in the plasma.", "The presence of matching networks is implicitly necessary because of the need to have some physical connection to the electrode so that electrical power can be applied.", "Thus, a plurality of resistive loads and associated networks are under automatic control so as to allow precise tailoring of the harmonic content of the plasma.", "This invention further includes a method of using the trapping network as a plasma harmonic detector to feed back the variations of the harmonics to the controller controlling the trapping network.", "The plasma harmonic detector detects the spectral content and spatial variations of the RF field in the plasma.", "The feedback signals from the plasma harmonic detector will adjust the matching networks to minimize a particular function.", "That particular function can be the spectral and spatial variations of certain harmonics at certain frequency.", "There is a multiplicity of the small matching networks around the electrode.", "By using the plasma harmonics detector with a specific algorithm, each of the matching networks can be tuned to achieve the best plasma uniformity results.", "This invention still further includes a method of using the apparatus as a process reliability detector by measuring the voltage across the resistive elements in the trap.", "By monitoring the amount of the power dissipated by the resistive element, a very precise evaluation of the plasma process conditions is made.", "Measuring the amount of power the plasma available in its harmonic range makes a very subtle and precise measurement of the condition of the plasma.", "FIG. 1 shows a simplified block diagram of a plasma processing system in accordance with a preferred embodiment of the present invention.", "Plasma processing system 100 comprises plasma excitation RF source 102 that supplies RF power at a fundamental frequency and a match network 104 .", "Trapping assembly 106 is coupled between match network 104 and an upper electrode 108 , which is located at the top of a plasma chamber 110 .", "Plasma chamber 110 encloses a plasma region in which plasma 112 will be initiated and maintained.", "A wafer chuck 114 is located at the bottom of the plasma region and is connected to a second RF source 116 via a second match network 118 .", "Electrodes 108 , 114 and sources 102 , 116 form a capacitively coupled RF plasma source that is used for performing an etch or deposition operation on a wafer mounted on chuck 114 .", "Source 116 acts primarily to impose a DC self-bias on wafer chuck 114 , which self-bias acts to attract ions to the surface of the wafer mounted on chuck 114 .", "Trapping assembly 106 is located on the main RF feed line to electrode 108 .", "Controller 130 is coupled to trapping assembly 106 .", "Controller 130 receives measurement data from trapping assembly 106 and sends control data to trapping assembly 106 .", "Controller 130 processes a portion of the measurement data to create control data.", "For example, the controller can perform a fast Fourier transform (FFT).", "In addition, controller 130 is used to control system operations and monitor the process.", "Controller 130 can comprise a computer or embedded processor, such as a digital signal processor (DSP).", "These types of processors are known to those skilled in the art.", "Plasma 112 can be excited and maintained by RF electromagnetic wave energy at the fundamental RF frequency that is passed to upper electrode 108 and plasma 112 by match network 104 and trapping assembly 106 .", "Trapping assembly 106 comprises a transmission line that is essentially transparent to RF electromagnetic wave energy at that frequency.", "Plasma 112 , in turn, converts some of the energy that it receives at the fundamental frequency into harmonics, and these are coupled back into upper electrode 108 and trapping assembly 106 .", "Energy at harmonic frequencies is strongly attenuated in the resistive loads of trapping assembly 106 , and a significant amount of this energy is dissipated in the form of heat along the length of trapping assembly 106 .", "The reduction of power at harmonic frequencies results in better electric field uniformity at and below upper electrode 108 , and thus better etch and deposition uniformity.", "FIGS. 2 a and 2 b show a simplified block diagram of a trapping assembly in accordance with a preferred embodiment of the present invention.", "Trapping assembly 106 comprises transmission line 170 and a plurality of frequency selective trap elements 172 .", "Transmission line 170 has a frustoconical coaxial geometry.", "This geometry primarily serves to reduce reflection points between match network 104 and upper electrode 108 .", "Preferably, transmission line 170 has a constant characteristic impedance, which also helps to reduce reflections.", "By making the ratio of the outer diameter to the inner diameter of transmission line 170 constant, a constant characteristic impedance is maintained.", "Alternately, the impedance of transmission line 170 can vary along its length.", "Transmission line 170 comprises inner conductor 174 and outer conductor 176 .", "Transmission line 170 can comprise any suitable configuration including a coaxial line, microstrip, or strip-line.", "Outer conductor 176 comprises a conically shaped sheet of low-loss conducting material such as copper, silver-plated copper, aluminum, or silver-plated aluminum.", "Outer conductor 176 is coupled to element 199 .", "Element 199 is part of the process chamber wall and supports trapping assembly 106 .", "Outer conductor 176 is coupled to ground via element 199 .", "Inner conductor 174 comprises a conically shaped block of low-loss conducting material such as copper, silver-plated copper, aluminum, or silver-plated aluminum.", "Inner conductor 174 is coupled to cooling plate 120 , and cooling plate 120 is coupled to electrode 108 .", "Inner conductor 174 comprises at least one cooling channel, as described below.", "Frequency selective trap elements 172 are electrically coupled to both inner conductor 174 and outer conductor 176 .", "Frequency selective trap elements 172 on the transmission line are tuned to harmonic frequencies to selectively monitor and control the harmonic content of the plasma.", "Frequency selective trap elements 172 are arranged in the space outside the outer conductor 176 and are in electrical contact with the inner conductor 174 through an opening in the outer conductor 176 .", "Alternately, frequency selective trap elements 172 can be positioned between the inner conductor 174 and the outer conductor 176 .", "Conductors 174 , 176 and the above-mentioned cooling channel are all axially symmetrical in this embodiment although they do not necessarily need to be.", "Outer conductor 176 constitutes a RF ground return terminal.", "The usual two match network output terminals are connected to inner conductor 174 and outer conductor 176 , respectively.", "This is achieved by mounting a match network output capacitor 128 directly on top of the inner conductor 174 .", "Outer conductor 176 is connected within the enclosure of match network 104 , which enclosure serves as a ground conductor.", "Upper electrode 108 is of the shower head type, provided with a plurality of passages (not shown) for delivery of process gas to the plasma region from a plenum 129 enclosed between electrode 108 and cooling plate 120 .", "The plenum is supplied with process gas by a gas feed line 132 .", "Gas feed line 132 is connected to a process gas source and extends along the vertical axis of the frustoconic outline of transmission line 170 .", "The lower surface of electrode 108 , the surface which faces the plasma region, is covered with a shower-head plate 136 , i.e., a plate provided with gas passages aligned with passages.", "Plate 136 may be made of material compatible with the chamber process, e.g., doped silicon.", "Plate 136 acts to prevent sputtering of material from electrode 108 .", "In addition, silicon plate 136 is made of a material compatible with the chamber process, to prevent contamination, and as such acts to separate the plasma from the lower surface of electrode 108 .", "This is particularly advantageous when electrode 108 contains a material that is not chemically compatible with the process.", "An alumina dielectric ring insulator 198 serves to extend coax transmission line below trapping assembly 106 and around cooling plate 120 and electrode 108 .", "The part of the transmission line constituted by insulator 198 does not absorb any RF and acts as a connection between the plasma and the trapping assembly 106 .", "Insulator 198 constitutes the dielectric of a coax line whose walls are metallic parts provided by cooling plate 120 , electrode 108 , and the chamber structure, a portion of which is shown as element 199 .", "A quartz shield ring 138 is attached around plate 136 and below electrode 108 .", "Quartz shield ring 138 is provided to cover the screws that are used to attach silicon plate 136 to electrode 108 , thereby isolating those screws from the plasma environment to prevent process contamination.", "Electrode 108 , plate 136 and ring 138 are all attached to, and supported by, cooling plate 120 , which is in turn supported by insulator ring 198 , the latter itself being supported by the chamber wall structure 199 .", "Cooling of the inner conductor 174 is performed through a coolant fluid circulated through a cooling channel 140 formed in inner conductor 174 .", "Cooling channel 140 is annular in shape and communicates with a coolant fluid source and a heat exchange element via inlet and outlet cooling lines 142 .", "As noted earlier herein, cooling channel 140 is axially symmetrical.", "The coolant fluid in channel 140 also acts to cool upper electrode 108 .", "Match network 104 (details of which are not shown) is mounted on top of trapping assembly 106 , and all cooling and gas feed connections are made within its RF enclosure.", "Match network 104 can be constructed according to principles well known in the art.", "FIG. 3 illustrates a simplified schematic representation of a frequency selective trap element in accordance with a preferred embodiment of the present invention.", "In the illustrated embodiment, frequency selective trap element 172 comprises input port 310 connected to inner conductor 174 , output port 312 connected to outer conductor 176 , control port 314 , transmission line 316 , coupling capacitor 318 , match network 320 , resistive load 322 , and probe 330 .", "In the illustrated embodiment, control port 314 is coupled to match network 320 and probe 330 .", "Alternately, other configurations can be envisioned.", "Control port 314 is coupled to controller 130 and comprises both control and sensor functions.", "Control port 314 is configured using at least one shielded cable.", "Resistive load 322 comprises at least one high power resistor that is mounted on a thermally conductive surface, such as the outer conductor.", "Match network 320 comprises a plurality of narrow band components, and wideband components.", "For example, variable capacitors and variable inductors can be used, or at higher frequencies, stub tuners and hybrid networks can be used.", "Match network 320 allows each frequency selective trap element 172 to be tuned to a particular harmonic frequency.", "For example, a control voltage can be provided to at least one varactor diode or at least one variable capacitor.", "Matching network techniques are known to those skilled in the art.", "In addition, match network 320 can provide measurement data from load resistor 322 and/or from match network 320 to controller 130 .", "For example, measurement data can include voltage, current, and/or power data.", "Desirably, probe 330 provides measurement data that includes voltage and current information from transmission line 316 .", "Alternately, measurement data can include magnitude and phase information.", "Controller 130 uses the measurement data to determine which frequency components are present and sends control data to match network 320 .", "Desirably, match network 320 is tuned to the proper frequency, and the desired signal level is achieved at load resistor 322 .", "Alternately, the desired signal level can be achieved at match network 320 or probe 330 .", "One or more frequency selective trap element 172 is used for each harmonic signal being controlled.", "Controller 130 is coupled to each one of the frequency selective trap elements 172 and tunes the match networks in all of the frequency selective trap elements 172 in the trapping assembly to achieve the proper harmonic profile.", "Desirably, proper harmonic profiles can be determined using experimental data from processes providing uniform etch rates.", "For example, historical data correlating process results to harmonic profiles can be used to produce algorithms for controller 130 .", "Harmonic profiles include fundamental and harmonic signal information.", "Also, controller 130 controls the operating levels of the RF sources used to generate the plasma.", "Controller 130 can adjust these operating levels to control the power delivered to the plasma at the fundamental frequency and to a lesser degree the harmonic levels.", "For example, controller 130 may have to increase the power delivered to the plasma at the fundamental frequency in order to maintain the desired plasma density.", "In addition, controller 130 controls the operating frequencies of the RF sources used to generate the plasma and can tune the operating frequencies to further control the harmonic profile.", "Those skilled in the art will also recognize that controller 130 controls match networks 104 and 108 ( FIG. 1 ) and can use these system level match networks to control the harmonic profile.", "By controlling the fundamental level and the harmonic levels, controller 130 generates a high density, uniform plasma.", "FIG. 4 shows an alternate embodiment of the present invention in which a trapping assembly is coupled between a match network and a lower electrode.", "Lower electrode comprises a wafer chuck for supporting wafer 470 while a plasma process is performed.", "RF power is supplied to match network 418 by power source 416 .", "Trapping assembly 406 comprises transmission line 480 and a plurality of frequency selective trap elements 472 .", "Transmission line 480 is a coaxial transmission line comprising inner conductor 474 , outer conductor 476 , and dielectric layer 478 .", "At least one frequency selective trap element 472 is coupled between and in electrical contact with conductors 474 and 476 .", "Frequency selective trap elements 472 selectively controls the amount of energy which arises within the plasma at frequencies that are harmonics of the fundamental frequency produced by power source 416 and also all other frequencies in the chamber associated with upper electrode plasma excitation (e.g., fundamental and harmonics of upper electrode), and which is conducted to trapping assembly 406 via chuck 414 , after being coupled into chuck 414 from the plasma.", "FIG. 5 shows an alternate embodiment of the present invention in which a trapping assembly comprising a plurality of transmission lines is coupled between a match network and an upper electrode.", "Trapping assembly 506 comprises a plurality of transmission lines 570 and a plurality of frequency selective trap elements 572 .", "Desirably, at least one frequency selective trap element 572 is coupled to each transmission line 570 .", "Transmission line 570 comprises first conductor 574 , second conductor 576 , and dielectric 578 .", "Transmission lines 570 can comprise any suitable configuration including coaxial line, microstrip, or strip-line.", "Transmission lines 570 can have different physical characteristics.", "One or more frequency selective trap elements can be tuned to selectively control the amount of energy, which arises within the plasma chamber at frequencies that are harmonics of the fundamental frequency.", "In addition, when multiple transmission lines are used in a trapping assembly, the transmission lines can be designed to make the trapping assembly more efficient.", "Alternately, the transmission lines can also comprise an absorber material, which can be used to further control the harmonic levels.", "While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof.", "The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.", "The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein." ]
CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is a continuation application of and claims the priority benefit of U.S. application Ser. No. 12/493,253 filed on Jun. 29, 2009, now allowed, which claims the priority benefit of Taiwan application serial no. 97138938, filed Oct. 9, 2008. The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of this specification. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to a liquid crystal display (LCD) panel and a manufacturing method thereof. More particularly, the present invention relates to an LCD panel applying a polymer-stabilized alignment technology and a manufacturing method thereof. [0004] 2. Description of Related Art [0005] At the current stage, LCD panel technologies that have been developed to satisfy the requirement of a wide viewing angle include: twisted nematic (TN) LCD panels equipped with wide viewing films, in-plane switching (IPS) LCD panels, fringe field switching LCD panels and multi-domain vertically alignment (MVA) LCD panels. Among these LCD panels, the MVA-LCD panels are widely used in various electronic devices. [0006] In a conventional MVA-LCD panel, an alignment structure is formed, such that liquid crystal (LC) molecules in different areas tilt in different angles and accomplish the wide viewing angle effect. However, the design of the MVA-LCD panel still has the issue regarding unfavorable display contrast. Hence, a polymer-stabilized alignment (PSA) LCD panel aiming at the establishment of a multi-domain alignment through a PSA manufacturing process has been proposed. [0007] The PSA manufacturing process includes first doping reactive monomers into a liquid crystal (LC) layer and applying a specific electrical field thereto. Next, the LC layer is irradiated by a light beam or a thermal source under the electrical field, and thereby the reactive monomers are polymerized and cured, such that a PSA layer is formed on a substrate at respective sides of the LC layer simultaneously. Here, the molecules of the PSA layer are arranged in a certain manner, which is conducive to tilting or arranging the LC molecules in different directions, so as to achieve the wide viewing angle effect. [0008] Besides, in order to enhance the alignment effect of the LC molecules, fine slits are formed on a pixel electrode or alignment protrusions are produced on a substrate in the PSA LCD panel. Nevertheless, the fine slits on the pixel electrode would result in loss of display brightness in the pixel and consequently affect display quality. On the other hand, the disposition of the alignment protrusions causes the LC molecules at peripheries of the alignment protrusions to tilt in discontinuous directions and result in light leakage. Therefore, display contrast of the LCD panel is reduced, and production of extra alignment protrusions results in burdens of the manufacturing process and affects the yield rate thereof. SUMMARY OF THE INVENTION [0009] The present invention is directed to a manufacturing method of an LCD panel to resolve a conventional issue regarding the structure design of the LCD panel that results in inability to enhance brightness or generation of light leakage. [0010] The present invention is further directed to an LCD panel to resolve an issue regarding loss of brightness of the LCD panel due to disposition of fine slits on a pixel electrode. [0011] The present invention is further directed to a manufacturing method of an LCD panel to complete a polymer-stabilized alignment (PSA) manufacturing process by means of scan lines and data lines providing necessary voltages for polymerization of a monomer material. [0012] The present invention provides a manufacturing method of an LCD panel. The manufacturing method includes following steps. A panel is provided, where the panel includes a first substrate, a second substrate and a liquid crystal (LC) layer. The first substrate has a plurality of scan lines and a plurality of data lines, and the scan lines intersect with the data lines respectively to define a plurality of pixel areas on the first substrate. The first substrate in every pixel area further includes an active device, a pixel electrode, an auxiliary electrode and a shielding electrode, where the active device is coupled to the corresponding scan lines and data lines. The pixel electrode is coupled to the active device. The auxiliary electrode is disposed on the pixel electrode and is coupled to the pixel electrode. The shielding electrode is disposed at peripheries of the pixel electrode and surrounds the auxiliary electrode. The second substrate has an opposite electrode. The LC layer is located between the first substrate and the second substrate, and the LC layer has a plurality of the LC molecules and a monomer material. Next, a first curing voltage is applied to the scan lines and a second curing voltage is applied to the data lines. Here, the first curing voltage is higher than an absolute value of the second curing voltage. At this time, the second curing voltage transmits to the pixel electrode and generates an electrical field in the LC layer to align the LC molecules at a pre-tilt angle. Subsequently, the monomer material in the LC layer is polymerized to form a first PSA layer between the LC layer and the first substrate and to form a second PSA layer between the LC layer and the second substrate. The electrical field is then removed. [0013] In one embodiment of the present invention, the method of polymerizing the monomer material in the LC layer includes a light irradiation of the monomer material. Practically, a power of the light irradiating the monomer material is from 50 mW to 1000 mW, for instance. Moreover, a time of light irradiation of the monomer material is from 50 seconds to 500 seconds. [0014] In one embodiment of the present invention, when the electrical field is applied to the LC layer, a voltage difference between the pixel electrode and the opposite electrode is from 5V to 40V. [0015] In one embodiment of the present invention, a voltage difference between the first curing voltage and the second curing voltage is greater than a threshold voltage of the active device. [0016] In one embodiment of the present invention, a voltage difference between the first curing voltage and the second curing voltage is greater than 7V. [0017] In one embodiment of the present invention, a potential of the opposite electrode and the shielding electrode includes a grounded potential. [0018] The present invention further provides an LCD panel which includes a first substrate, a second substrate, an LC layer, a first PSA layer and a second PSA layer. The first substrate has a plurality of scan lines and a plurality of data lines. The scan lines intersect with the data lines respectively and define a plurality of pixel areas on the first substrate. Besides, the first substrate in every pixel area includes an active device, a pixel electrode, an auxiliary pixel and a shielding electrode, where the active device is coupled to the corresponding scan line and data line. The pixel electrode is coupled to the active device. The auxiliary electrode is disposed on the pixel electrode and is coupled to the pixel electrode. The shielding electrode is disposed at peripheries of the pixel electrode and surrounds the auxiliary electrode. The second substrate has an opposite electrode. The LC layer is disposed between the first substrate and the second substrate, and the LC layer has a plurality of LC molecules. The first PSA layer is disposed between the first substrate and the LC layer. In addition, the second PSA layer is disposed between the second substrate and the LC layer. [0019] In one embodiment of the present invention, the first P SA layer and the second PSA layer are polymerized by a monomer material doped in the LC layer. Practically, the monomer material is a light reactive monomer material, for example. The monomer material is polymerized to form the first PSA layer and the second PSA layer through a light irradiation, where a power of the light irradiating the monomer material is from 50 mW to 1000 mW. Moreover, a time that the light irradiates the monomer material is from 50 seconds to 500 seconds. Before the irradiation, an electrical field is further applied to the LC layer through the opposite electrode and the pixel electrode, such that the LC molecules are arranged at a pre-tilt angle. When applying the electrical field to the LC layer, a voltage difference between the pixel electrode and the opposite electrode is from 5V to 40V. Besides, when applying the electrical field to the LC molecules, a voltage applied to the scan lines is higher than an absolute value of a voltage applied to the data lines. In addition, a voltage difference between the scan lines and the data lines is greater than a threshold voltage of the active device. When applying the electrical field to the LC molecules, a voltage difference between the scan lines and the data lines is greater than 7V, for instance. [0020] In one embodiment of the present invention, the above-mentioned first substrate further includes a plurality of color filter units respectively disposed in the pixel areas. [0021] In one embodiment of the present invention, the second substrate further includes a plurality of color filter units respectively corresponding to the pixel areas. [0022] The present invention provides another manufacturing method of an LCD panel. The method includes following steps. A panel is provided. The panel includes a first substrate, a second substrate and an LC layer. Here, the first substrate has a scan line and a data line. The scan line intersects with the data line respectively. The first substrate also includes an active device and a pixel electrode, where the active device is coupled to the scan line and the data line, and the pixel electrode is coupled to the active device. The second substrate has an opposite electrode. The LC layer is located between the first substrate and the second substrate, and the LC layer has a plurality of LC molecules and a monomer material. Then, a first curing voltage is applied to the scan line, and a second curing voltage is applied to the data line. Here, the first curing voltage is higher than an absolute value of the second curing voltage. The second curing voltage flows into the pixel electrode and generates an electrical field in the LC layer to align the LC molecules at a pre-tilt angle. Subsequently, the monomer material in the LC layer is polymerized to form a first PSA layer between the first substrate and the LC layer and to form a second PSA layer between the second substrate and the LC layer. The electrical field is then removed. [0023] The present invention applies the PSA technology in the LCD panel having the design of the auxiliary electrode and the shielding electrode. Therefore, the LCD panel of the present invention utilizes the PSA layer to provide an appropriate anchor force in cooperation with the structural design of the auxiliary electrode, so as to render the LC molecules in a multi-domain arrangement. In other words, the LCD panel of the present invention does not require disposition of the fine slits in the pixel electrode or disposition of the alignment protrusions on the substrate, which conduces in the enhancement of the display brightness of the LCD panel and increases light transmittance. [0024] To make the above and other features and advantages of the present invention more comprehensible, several embodiments accompanied with figures are detailed as follows. BRIEF DESCRIPTION OF THE DRAWINGS [0025] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. [0026] FIG. 1 is a schematic top view of an LCD panel of one embodiment of the present invention. [0027] FIG. 2A and 2B show a manufacturing method of the LCD panel taken along cross-sectional lines A-A′, B-B′, and C-C′ in FIG. 1 . [0028] FIGS. 3A and 3B respectively show a schematic top view and a schematic cross-sectional view of the first substrate of the LCD panel in another embodiment of the present invention. DESCRIPTION OF EMBODIMENTS [0029] FIG. 1 is a schematic top view of a liquid crystal display (LCD) panel in an embodiment of the present invention. FIG. 2A and 2B show a manufacturing method of the LCD panel taken along cross-sectional lines A-A′, B-B′, and C-C′ in FIG. 1 . Referring to FIG. 1 and FIG. 2A , the manufacturing method of an LCD panel 100 in the present invention includes providing a panel 100 ′ at first. The panel 100 ′ includes a first substrate 110 , a second substrate 130 , and a liquid crystal (LC) layer 150 . The first substrate 110 has an active device array 110 ′. The second substrate 130 has an opposite electrode 132 . The LC layer 150 is disposed between the first substrate 110 and the second substrate 130 , and the LC layer 150 has a plurality of liquid crystal (LC) molecules 152 and a monomer material 154 that is able to be polymerized. [0030] More specifically, the first substrate 110 includes a plurality of scan lines 112 and a plurality of data lines 114 . In FIG. 1 , only one scan line 112 and two data lines 114 are shown to provide a clear indication of each element. The scan lines 112 intersect with the data lines 114 , respectively, so as to define a plurality of pixel areas P arranged in matrix on the first substrate 110 . The first substrate 110 in each of the pixel areas further includes an active device 116 , a pixel electrode 118 , an auxiliary electrode 120 , and a shielding electrode 122 . The active device 116 is coupled to the corresponding scan line 112 and the corresponding data line 114 , and the pixel electrode 118 is coupled to the active device 116 . The auxiliary electrode 120 is disposed on the pixel electrode 118 and is coupled to the pixel electrode 118 . The shielding electrode 122 is located at peripheries of the pixel electrode 118 and is surrounding the auxiliary electrode 120 . Notably, the shielding electrode 122 can be used as a capacitor electrode in the LCD panel 100 . The shielding electrode 122 and the pixel electrode 118 form a storage capacitor to maintain a display voltage of the pixel electrode 118 . [0031] Then, referring to both FIG. 1 and FIG. 2B , a first curing voltage Vcur 1 , i.e., a scan line curing voltage, is applied to the scan lines 112 , and a second curing voltage Vcur 2 , i.e., a data line curing voltage, is applied to the data lines 114 . Moreover, an opposite potential of the opposite electrode 132 and the shielding electrode 122 includes a grounded potential or a fixed potential. Under such circumstances, the second curing voltage Vcur 2 transmits to the pixel electrode 118 , and an electrical field E is generated in the LC layer 150 . The LC molecules 152 are then aligned at a pre-tilt angle. [0032] In the present embodiment, the first curing voltage Vur 1 is substantially higher than an absolute value of the second curing voltage Vcur 2 . Specifically, when the electrical field E is applied to the LC layer 150 , a voltage difference between the pixel electrode 118 and the opposite electrode 132 is from 5V to 40V. Besides, in the manufacturing method, a voltage difference between the first curing voltage Vcur 1 and the second curing voltage Vcur 2 is greater than a threshold voltage of the active device 116 , for instance. Practically, the voltage difference between the first curing voltage Vcur 1 and the second curing voltage Vcur 2 is greater than 7V, for instance, which allows the second curing voltage Vcur 2 to be transmitted to the pixel electrode 118 successfully. [0033] In detail, referring to FIG. 2A and 2B , the method of polymerizing the monomer material 154 in the LC layer 150 includes irradiating the monomer material 154 by using an ultraviolet (UV) light, for example. A power of the UV light irradiating the monomer material 154 is from 50 mW to 1000 mW, for instance. Furthermore, a time that the UV light irradiating the monomer material 154 can be from 50 seconds to 500 seconds. Practically, in the steps of irradiation of the monomer material 154 , the power and the time of irradiation of the monomer material 154 can be complemented by modification, so as to satisfy different manufacturing requirements. The present invention is not limited to the power and the time of irradiating the monomer material 154 mentioned above. Additionally, the present embodiment is elaborated by taking a light reactive monomer material 154 as an example. When the monomer material 154 is a thermal reactive monomer material or any other material, alternative methods should be utilized for the polymerization of the monomer material 154 . [0034] The manufacturing method of the present embodiment utilizes the irradiating method for polymerizing the monomer material 154 in the LC layer 150 , so as to form a polymer layer on inner surfaces of the first substrate 110 and the second substrate 130 . Consequently, a first polymer stabilized alignment (PSA) layer 162 is formed between the first substrate 110 and the LC layer 150 , and a second PSA layer 164 is formed between the second substrate 130 and the LC layer 150 . Here, FIG. 2B is illustrated schematically. The electrical field E is then removed to complete the fabrication of the LCD panel 100 . [0035] In the first substrate 110 of the present embodiment, each of the pixel electrodes 118 and the auxiliary electrode 120 disposed above each of the pixel electrodes 118 belong to different film layers and are disposed on different planes. Thus, when the pixel electrode 118 is applied with the second curing voltage Vcur 2 , a fringe field effect (FFE) would be generated at the edge of the auxiliary electrode 120 . Moreover, the shielding electrode 122 surrounding the auxiliary electrode 120 would also generate the FFE at the edge of the pixel electrode 118 . Therefore, the electrical field E is not evenly distributed in each of the pixel areas P. [0036] Under the FFE provided by the auxiliary electrode 120 and the shielding electrode 122 , the LC molecules 152 are aligned in a specific arrangement, such as the condition shown in FIG. 2B . In other words, under the structural design of the first substrate 100 , when the second curing voltage Vcur 2 transmits to the pixel electrode 118 , the LC molecules 152 at different locations would be arranged at different pre-tilt angles. At this time, the alignment manner of the LC molecule 152 affects the polymerization process of the monomer material 154 . Thus, the alignment manner of the polymers in the first PSA layer 162 and the second PSA layer 164 has specific structural characteristics. In the present invention, the second curing voltage Vcur 2 is directly applied to the pixel electrode 118 , where the second curing voltage Vcur 2 provides a more stable and more accurate liquid crystal alignment effect than the curing voltage of a common electrode coupled to the pixel electrode 118 . [0037] After the electrical field E is removed, the specific structural characteristics of the first PSA layer 162 and the second PSA layer 164 provide a certain alignment anchor force and conduce in enhancement of a response rate of the LC molecules 152 . In other words, the present embodiment does not require the design of fine slits or fine protrusions for performing the PSA manufacturing process to form the MVA-LCD panel 100 , and a relatively stable alignment effect can still be achieved. Therefore, in the LCD panel 100 produced by the manufacturing process described above, the LC molecules 152 have an efficient response rate. Moreover, the display quality of the LCD panel 100 is not affected by the fine slits or the alignment protrusions, and is further elevated. [0038] In the present embodiment, the pixel electrode 118 is entirely disposed in the pixel area P. Hence, the LC molecules in the entire pixel area P would proceed to display when the LCD panel 100 displays an image. In comparison with the conventional design in which the LC molecules above the fine slits cannot proceed to display, the LCD panel 100 has favorable display brightness. In addition, in order for the LCD panel 100 to accomplish a multi-color display effect, the first substrate 110 or the second substrate 130 further includes a plurality of color filter units, each located in the corresponding pixel area P. That is, the second substrate 130 can be a color filter substrate, or the first substrate 110 can have a design of a color filter on array (COA) or an array on color filter (AOC). [0039] Notably, the manufacturing method of the present embodiment is not limited to the application of the LCD panel 100 as shown in FIG. 1 . In other embodiments of the present invention, the above-mentioned manufacturing method can also be applied to LCD panels that do not include the auxiliary electrodes 120 and the shielding electrodes 122 . Besides, in the sequence of stacking metal films in the LCD panel 100 as shown in FIG. 2B , the data line 114 is manufactured by the first metal layer directly disposed on the substrate while the scan line 112 is manufactured by the second metal layer disposed on an insulating layer. Meanwhile, the auxiliary electrode 120 and the shielding electrode 122 are manufactured by the third metal layer. Nevertheless, the present invention should not be construed as limited to the embodiments set forth herein. In another embodiment of the present invention, the data line 114 and the scan line 112 can also be manufactured respectively by the second metal layer and the first metal layer. [0040] FIGS. 3A and 3B respectively show a schematic top view and a schematic cross-sectional view of the first substrate of the LCD panel in another embodiment of the present invention. Here, FIG. 3B shows cross-sectional lines D-D′, and E-E′ depicted in FIG. 3A . Referring to FIGS. 3A and 3B , a first substrate 300 has a plurality of scan lines 310 and a plurality of data lines 320 . Here, as an example, FIG. 3A shows two lines each. The scan lines 310 intersect with the data lines 320 respectively and define a plurality of pixel areas P on the first substrate 300 . The first substrate 300 in each of the pixel areas P further includes an active device 330 , a pixel electrode 340 , two auxiliary electrodes 350 , and a shielding electrode 360 . The electrical connection relationship between the aforesaid devices is identical to the electrical connection relationship between the devices in the first substrate 110 described in the previous embodiment of the present invention. Moreover, the two auxiliary electrodes 350 are surrounded by the shielding electrode 360 . [0041] In the first substrate 300 , the application of the two auxiliary electrodes 350 in an LCD panel allows the LC molecules in the LCD panel to be aligned in more multiple domains. [0042] In other words, the design of the first substrate 300 further enhances the wide viewing angle display effect of the LCD panel. Furthermore, because the two auxiliary electrodes 350 are disposed in the present embodiment, the shielding electrode 360 of the present invention is presented as the configuration of “θ”. [0043] Specifically, the cross-sectional view of FIG. 3B shows that the scan line 310 in the present embodiment is manufactured by the first metal layer, the data line 320 is manufactured by the second metal layer, and the auxiliary electrode 350 and the shielding electrode 360 are both manufactured by the third metal layer. In other words, the manufacturing sequence of the first substrate 300 is different from the manufacturing sequence of the first substrate 110 . [0044] Additionally, in the first substrate 300 , the auxiliary electrode 350 and the pixel electrode 340 belong to different films and are disposed on different planes. Therefore, when a voltage is applied to the pixel electrode 340 , the FFE is generated between the auxiliary electrode 350 and the pixel electrode 340 . Similarly, a corresponding FFE is generated between the shielding electrode 360 and the pixel electrode 340 . Thus, when the first substrate 300 applies the manufacturing method of the LCD panel described in the previous embodiment, the LC layer of the LCD panel can have the multi-domain alignment. In other words, the application of the first substrate 300 in the above-mentioned manufacturing method gives rise to the increase in the response rate of the LC molecules in the LCD panel and the elevation in display quality of the LCD panel. [0045] In light of the foregoing, different curing voltages are applied respectively to the scan lines and the data lines for directly supplying the curing voltages to the pixel electrode according to the present invention. Thereby, the PSA manufacturing process can be performed on the LCD panel without the dispositions of the fine slits and the alignment protrusions. As such, the LCD panel of the present invention has good display brightness, and the response rate of the LC molecules in the LCD panel remains satisfactory. In general, the manufacturing method of the LCD panel of the present invention improves the quality of the LCD panel. [0046] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
A liquid crystal display panel including a first substrate, a second substrate, a liquid crystal layer, a scan line, a data line intersects the scan line, an active device, a pixel electrode, an insulating layer covering the pixel electrode, an auxiliary electrode, a shielding electrode, and a first polymer stabilized alignment (PSA) layer is provided. The liquid crystal layer between the first substrate and the second substrate includes liquid crystal molecules and a monomer material. The active device includes three terminals coupled to the scan line, the data line, and the pixel electrode. The auxiliary electrode on the insulating layer is electrically connected to the pixel electrode. The shielding electrode on the insulating layer located at peripheries of the pixel electrode surrounds the auxiliary electrode. The first PSA layer between the first substrate and the liquid crystal layer is polymerized from the monomer material in the liquid crystal layer.
Provide a concise summary of the essential information conveyed in the given context.
[ "CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is a continuation application of and claims the priority benefit of U.S. application Ser.", "No. 12/493,253 filed on Jun. 29, 2009, now allowed, which claims the priority benefit of Taiwan application serial no. 97138938, filed Oct. 9, 2008.", "The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of this specification.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] The present invention relates to a liquid crystal display (LCD) panel and a manufacturing method thereof.", "More particularly, the present invention relates to an LCD panel applying a polymer-stabilized alignment technology and a manufacturing method thereof.", "[0004] 2.", "Description of Related Art [0005] At the current stage, LCD panel technologies that have been developed to satisfy the requirement of a wide viewing angle include: twisted nematic (TN) LCD panels equipped with wide viewing films, in-plane switching (IPS) LCD panels, fringe field switching LCD panels and multi-domain vertically alignment (MVA) LCD panels.", "Among these LCD panels, the MVA-LCD panels are widely used in various electronic devices.", "[0006] In a conventional MVA-LCD panel, an alignment structure is formed, such that liquid crystal (LC) molecules in different areas tilt in different angles and accomplish the wide viewing angle effect.", "However, the design of the MVA-LCD panel still has the issue regarding unfavorable display contrast.", "Hence, a polymer-stabilized alignment (PSA) LCD panel aiming at the establishment of a multi-domain alignment through a PSA manufacturing process has been proposed.", "[0007] The PSA manufacturing process includes first doping reactive monomers into a liquid crystal (LC) layer and applying a specific electrical field thereto.", "Next, the LC layer is irradiated by a light beam or a thermal source under the electrical field, and thereby the reactive monomers are polymerized and cured, such that a PSA layer is formed on a substrate at respective sides of the LC layer simultaneously.", "Here, the molecules of the PSA layer are arranged in a certain manner, which is conducive to tilting or arranging the LC molecules in different directions, so as to achieve the wide viewing angle effect.", "[0008] Besides, in order to enhance the alignment effect of the LC molecules, fine slits are formed on a pixel electrode or alignment protrusions are produced on a substrate in the PSA LCD panel.", "Nevertheless, the fine slits on the pixel electrode would result in loss of display brightness in the pixel and consequently affect display quality.", "On the other hand, the disposition of the alignment protrusions causes the LC molecules at peripheries of the alignment protrusions to tilt in discontinuous directions and result in light leakage.", "Therefore, display contrast of the LCD panel is reduced, and production of extra alignment protrusions results in burdens of the manufacturing process and affects the yield rate thereof.", "SUMMARY OF THE INVENTION [0009] The present invention is directed to a manufacturing method of an LCD panel to resolve a conventional issue regarding the structure design of the LCD panel that results in inability to enhance brightness or generation of light leakage.", "[0010] The present invention is further directed to an LCD panel to resolve an issue regarding loss of brightness of the LCD panel due to disposition of fine slits on a pixel electrode.", "[0011] The present invention is further directed to a manufacturing method of an LCD panel to complete a polymer-stabilized alignment (PSA) manufacturing process by means of scan lines and data lines providing necessary voltages for polymerization of a monomer material.", "[0012] The present invention provides a manufacturing method of an LCD panel.", "The manufacturing method includes following steps.", "A panel is provided, where the panel includes a first substrate, a second substrate and a liquid crystal (LC) layer.", "The first substrate has a plurality of scan lines and a plurality of data lines, and the scan lines intersect with the data lines respectively to define a plurality of pixel areas on the first substrate.", "The first substrate in every pixel area further includes an active device, a pixel electrode, an auxiliary electrode and a shielding electrode, where the active device is coupled to the corresponding scan lines and data lines.", "The pixel electrode is coupled to the active device.", "The auxiliary electrode is disposed on the pixel electrode and is coupled to the pixel electrode.", "The shielding electrode is disposed at peripheries of the pixel electrode and surrounds the auxiliary electrode.", "The second substrate has an opposite electrode.", "The LC layer is located between the first substrate and the second substrate, and the LC layer has a plurality of the LC molecules and a monomer material.", "Next, a first curing voltage is applied to the scan lines and a second curing voltage is applied to the data lines.", "Here, the first curing voltage is higher than an absolute value of the second curing voltage.", "At this time, the second curing voltage transmits to the pixel electrode and generates an electrical field in the LC layer to align the LC molecules at a pre-tilt angle.", "Subsequently, the monomer material in the LC layer is polymerized to form a first PSA layer between the LC layer and the first substrate and to form a second PSA layer between the LC layer and the second substrate.", "The electrical field is then removed.", "[0013] In one embodiment of the present invention, the method of polymerizing the monomer material in the LC layer includes a light irradiation of the monomer material.", "Practically, a power of the light irradiating the monomer material is from 50 mW to 1000 mW, for instance.", "Moreover, a time of light irradiation of the monomer material is from 50 seconds to 500 seconds.", "[0014] In one embodiment of the present invention, when the electrical field is applied to the LC layer, a voltage difference between the pixel electrode and the opposite electrode is from 5V to 40V.", "[0015] In one embodiment of the present invention, a voltage difference between the first curing voltage and the second curing voltage is greater than a threshold voltage of the active device.", "[0016] In one embodiment of the present invention, a voltage difference between the first curing voltage and the second curing voltage is greater than 7V.", "[0017] In one embodiment of the present invention, a potential of the opposite electrode and the shielding electrode includes a grounded potential.", "[0018] The present invention further provides an LCD panel which includes a first substrate, a second substrate, an LC layer, a first PSA layer and a second PSA layer.", "The first substrate has a plurality of scan lines and a plurality of data lines.", "The scan lines intersect with the data lines respectively and define a plurality of pixel areas on the first substrate.", "Besides, the first substrate in every pixel area includes an active device, a pixel electrode, an auxiliary pixel and a shielding electrode, where the active device is coupled to the corresponding scan line and data line.", "The pixel electrode is coupled to the active device.", "The auxiliary electrode is disposed on the pixel electrode and is coupled to the pixel electrode.", "The shielding electrode is disposed at peripheries of the pixel electrode and surrounds the auxiliary electrode.", "The second substrate has an opposite electrode.", "The LC layer is disposed between the first substrate and the second substrate, and the LC layer has a plurality of LC molecules.", "The first PSA layer is disposed between the first substrate and the LC layer.", "In addition, the second PSA layer is disposed between the second substrate and the LC layer.", "[0019] In one embodiment of the present invention, the first P SA layer and the second PSA layer are polymerized by a monomer material doped in the LC layer.", "Practically, the monomer material is a light reactive monomer material, for example.", "The monomer material is polymerized to form the first PSA layer and the second PSA layer through a light irradiation, where a power of the light irradiating the monomer material is from 50 mW to 1000 mW.", "Moreover, a time that the light irradiates the monomer material is from 50 seconds to 500 seconds.", "Before the irradiation, an electrical field is further applied to the LC layer through the opposite electrode and the pixel electrode, such that the LC molecules are arranged at a pre-tilt angle.", "When applying the electrical field to the LC layer, a voltage difference between the pixel electrode and the opposite electrode is from 5V to 40V.", "Besides, when applying the electrical field to the LC molecules, a voltage applied to the scan lines is higher than an absolute value of a voltage applied to the data lines.", "In addition, a voltage difference between the scan lines and the data lines is greater than a threshold voltage of the active device.", "When applying the electrical field to the LC molecules, a voltage difference between the scan lines and the data lines is greater than 7V, for instance.", "[0020] In one embodiment of the present invention, the above-mentioned first substrate further includes a plurality of color filter units respectively disposed in the pixel areas.", "[0021] In one embodiment of the present invention, the second substrate further includes a plurality of color filter units respectively corresponding to the pixel areas.", "[0022] The present invention provides another manufacturing method of an LCD panel.", "The method includes following steps.", "A panel is provided.", "The panel includes a first substrate, a second substrate and an LC layer.", "Here, the first substrate has a scan line and a data line.", "The scan line intersects with the data line respectively.", "The first substrate also includes an active device and a pixel electrode, where the active device is coupled to the scan line and the data line, and the pixel electrode is coupled to the active device.", "The second substrate has an opposite electrode.", "The LC layer is located between the first substrate and the second substrate, and the LC layer has a plurality of LC molecules and a monomer material.", "Then, a first curing voltage is applied to the scan line, and a second curing voltage is applied to the data line.", "Here, the first curing voltage is higher than an absolute value of the second curing voltage.", "The second curing voltage flows into the pixel electrode and generates an electrical field in the LC layer to align the LC molecules at a pre-tilt angle.", "Subsequently, the monomer material in the LC layer is polymerized to form a first PSA layer between the first substrate and the LC layer and to form a second PSA layer between the second substrate and the LC layer.", "The electrical field is then removed.", "[0023] The present invention applies the PSA technology in the LCD panel having the design of the auxiliary electrode and the shielding electrode.", "Therefore, the LCD panel of the present invention utilizes the PSA layer to provide an appropriate anchor force in cooperation with the structural design of the auxiliary electrode, so as to render the LC molecules in a multi-domain arrangement.", "In other words, the LCD panel of the present invention does not require disposition of the fine slits in the pixel electrode or disposition of the alignment protrusions on the substrate, which conduces in the enhancement of the display brightness of the LCD panel and increases light transmittance.", "[0024] To make the above and other features and advantages of the present invention more comprehensible, several embodiments accompanied with figures are detailed as follows.", "BRIEF DESCRIPTION OF THE DRAWINGS [0025] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification.", "The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.", "[0026] FIG. 1 is a schematic top view of an LCD panel of one embodiment of the present invention.", "[0027] FIG. 2A and 2B show a manufacturing method of the LCD panel taken along cross-sectional lines A-A′, B-B′, and C-C′ in FIG. 1 .", "[0028] FIGS. 3A and 3B respectively show a schematic top view and a schematic cross-sectional view of the first substrate of the LCD panel in another embodiment of the present invention.", "DESCRIPTION OF EMBODIMENTS [0029] FIG. 1 is a schematic top view of a liquid crystal display (LCD) panel in an embodiment of the present invention.", "FIG. 2A and 2B show a manufacturing method of the LCD panel taken along cross-sectional lines A-A′, B-B′, and C-C′ in FIG. 1 .", "Referring to FIG. 1 and FIG. 2A , the manufacturing method of an LCD panel 100 in the present invention includes providing a panel 100 ′ at first.", "The panel 100 ′ includes a first substrate 110 , a second substrate 130 , and a liquid crystal (LC) layer 150 .", "The first substrate 110 has an active device array 110 ′.", "The second substrate 130 has an opposite electrode 132 .", "The LC layer 150 is disposed between the first substrate 110 and the second substrate 130 , and the LC layer 150 has a plurality of liquid crystal (LC) molecules 152 and a monomer material 154 that is able to be polymerized.", "[0030] More specifically, the first substrate 110 includes a plurality of scan lines 112 and a plurality of data lines 114 .", "In FIG. 1 , only one scan line 112 and two data lines 114 are shown to provide a clear indication of each element.", "The scan lines 112 intersect with the data lines 114 , respectively, so as to define a plurality of pixel areas P arranged in matrix on the first substrate 110 .", "The first substrate 110 in each of the pixel areas further includes an active device 116 , a pixel electrode 118 , an auxiliary electrode 120 , and a shielding electrode 122 .", "The active device 116 is coupled to the corresponding scan line 112 and the corresponding data line 114 , and the pixel electrode 118 is coupled to the active device 116 .", "The auxiliary electrode 120 is disposed on the pixel electrode 118 and is coupled to the pixel electrode 118 .", "The shielding electrode 122 is located at peripheries of the pixel electrode 118 and is surrounding the auxiliary electrode 120 .", "Notably, the shielding electrode 122 can be used as a capacitor electrode in the LCD panel 100 .", "The shielding electrode 122 and the pixel electrode 118 form a storage capacitor to maintain a display voltage of the pixel electrode 118 .", "[0031] Then, referring to both FIG. 1 and FIG. 2B , a first curing voltage Vcur 1 , i.e., a scan line curing voltage, is applied to the scan lines 112 , and a second curing voltage Vcur 2 , i.e., a data line curing voltage, is applied to the data lines 114 .", "Moreover, an opposite potential of the opposite electrode 132 and the shielding electrode 122 includes a grounded potential or a fixed potential.", "Under such circumstances, the second curing voltage Vcur 2 transmits to the pixel electrode 118 , and an electrical field E is generated in the LC layer 150 .", "The LC molecules 152 are then aligned at a pre-tilt angle.", "[0032] In the present embodiment, the first curing voltage Vur 1 is substantially higher than an absolute value of the second curing voltage Vcur 2 .", "Specifically, when the electrical field E is applied to the LC layer 150 , a voltage difference between the pixel electrode 118 and the opposite electrode 132 is from 5V to 40V.", "Besides, in the manufacturing method, a voltage difference between the first curing voltage Vcur 1 and the second curing voltage Vcur 2 is greater than a threshold voltage of the active device 116 , for instance.", "Practically, the voltage difference between the first curing voltage Vcur 1 and the second curing voltage Vcur 2 is greater than 7V, for instance, which allows the second curing voltage Vcur 2 to be transmitted to the pixel electrode 118 successfully.", "[0033] In detail, referring to FIG. 2A and 2B , the method of polymerizing the monomer material 154 in the LC layer 150 includes irradiating the monomer material 154 by using an ultraviolet (UV) light, for example.", "A power of the UV light irradiating the monomer material 154 is from 50 mW to 1000 mW, for instance.", "Furthermore, a time that the UV light irradiating the monomer material 154 can be from 50 seconds to 500 seconds.", "Practically, in the steps of irradiation of the monomer material 154 , the power and the time of irradiation of the monomer material 154 can be complemented by modification, so as to satisfy different manufacturing requirements.", "The present invention is not limited to the power and the time of irradiating the monomer material 154 mentioned above.", "Additionally, the present embodiment is elaborated by taking a light reactive monomer material 154 as an example.", "When the monomer material 154 is a thermal reactive monomer material or any other material, alternative methods should be utilized for the polymerization of the monomer material 154 .", "[0034] The manufacturing method of the present embodiment utilizes the irradiating method for polymerizing the monomer material 154 in the LC layer 150 , so as to form a polymer layer on inner surfaces of the first substrate 110 and the second substrate 130 .", "Consequently, a first polymer stabilized alignment (PSA) layer 162 is formed between the first substrate 110 and the LC layer 150 , and a second PSA layer 164 is formed between the second substrate 130 and the LC layer 150 .", "Here, FIG. 2B is illustrated schematically.", "The electrical field E is then removed to complete the fabrication of the LCD panel 100 .", "[0035] In the first substrate 110 of the present embodiment, each of the pixel electrodes 118 and the auxiliary electrode 120 disposed above each of the pixel electrodes 118 belong to different film layers and are disposed on different planes.", "Thus, when the pixel electrode 118 is applied with the second curing voltage Vcur 2 , a fringe field effect (FFE) would be generated at the edge of the auxiliary electrode 120 .", "Moreover, the shielding electrode 122 surrounding the auxiliary electrode 120 would also generate the FFE at the edge of the pixel electrode 118 .", "Therefore, the electrical field E is not evenly distributed in each of the pixel areas P. [0036] Under the FFE provided by the auxiliary electrode 120 and the shielding electrode 122 , the LC molecules 152 are aligned in a specific arrangement, such as the condition shown in FIG. 2B .", "In other words, under the structural design of the first substrate 100 , when the second curing voltage Vcur 2 transmits to the pixel electrode 118 , the LC molecules 152 at different locations would be arranged at different pre-tilt angles.", "At this time, the alignment manner of the LC molecule 152 affects the polymerization process of the monomer material 154 .", "Thus, the alignment manner of the polymers in the first PSA layer 162 and the second PSA layer 164 has specific structural characteristics.", "In the present invention, the second curing voltage Vcur 2 is directly applied to the pixel electrode 118 , where the second curing voltage Vcur 2 provides a more stable and more accurate liquid crystal alignment effect than the curing voltage of a common electrode coupled to the pixel electrode 118 .", "[0037] After the electrical field E is removed, the specific structural characteristics of the first PSA layer 162 and the second PSA layer 164 provide a certain alignment anchor force and conduce in enhancement of a response rate of the LC molecules 152 .", "In other words, the present embodiment does not require the design of fine slits or fine protrusions for performing the PSA manufacturing process to form the MVA-LCD panel 100 , and a relatively stable alignment effect can still be achieved.", "Therefore, in the LCD panel 100 produced by the manufacturing process described above, the LC molecules 152 have an efficient response rate.", "Moreover, the display quality of the LCD panel 100 is not affected by the fine slits or the alignment protrusions, and is further elevated.", "[0038] In the present embodiment, the pixel electrode 118 is entirely disposed in the pixel area P. Hence, the LC molecules in the entire pixel area P would proceed to display when the LCD panel 100 displays an image.", "In comparison with the conventional design in which the LC molecules above the fine slits cannot proceed to display, the LCD panel 100 has favorable display brightness.", "In addition, in order for the LCD panel 100 to accomplish a multi-color display effect, the first substrate 110 or the second substrate 130 further includes a plurality of color filter units, each located in the corresponding pixel area P. That is, the second substrate 130 can be a color filter substrate, or the first substrate 110 can have a design of a color filter on array (COA) or an array on color filter (AOC).", "[0039] Notably, the manufacturing method of the present embodiment is not limited to the application of the LCD panel 100 as shown in FIG. 1 .", "In other embodiments of the present invention, the above-mentioned manufacturing method can also be applied to LCD panels that do not include the auxiliary electrodes 120 and the shielding electrodes 122 .", "Besides, in the sequence of stacking metal films in the LCD panel 100 as shown in FIG. 2B , the data line 114 is manufactured by the first metal layer directly disposed on the substrate while the scan line 112 is manufactured by the second metal layer disposed on an insulating layer.", "Meanwhile, the auxiliary electrode 120 and the shielding electrode 122 are manufactured by the third metal layer.", "Nevertheless, the present invention should not be construed as limited to the embodiments set forth herein.", "In another embodiment of the present invention, the data line 114 and the scan line 112 can also be manufactured respectively by the second metal layer and the first metal layer.", "[0040] FIGS. 3A and 3B respectively show a schematic top view and a schematic cross-sectional view of the first substrate of the LCD panel in another embodiment of the present invention.", "Here, FIG. 3B shows cross-sectional lines D-D′, and E-E′ depicted in FIG. 3A .", "Referring to FIGS. 3A and 3B , a first substrate 300 has a plurality of scan lines 310 and a plurality of data lines 320 .", "Here, as an example, FIG. 3A shows two lines each.", "The scan lines 310 intersect with the data lines 320 respectively and define a plurality of pixel areas P on the first substrate 300 .", "The first substrate 300 in each of the pixel areas P further includes an active device 330 , a pixel electrode 340 , two auxiliary electrodes 350 , and a shielding electrode 360 .", "The electrical connection relationship between the aforesaid devices is identical to the electrical connection relationship between the devices in the first substrate 110 described in the previous embodiment of the present invention.", "Moreover, the two auxiliary electrodes 350 are surrounded by the shielding electrode 360 .", "[0041] In the first substrate 300 , the application of the two auxiliary electrodes 350 in an LCD panel allows the LC molecules in the LCD panel to be aligned in more multiple domains.", "[0042] In other words, the design of the first substrate 300 further enhances the wide viewing angle display effect of the LCD panel.", "Furthermore, because the two auxiliary electrodes 350 are disposed in the present embodiment, the shielding electrode 360 of the present invention is presented as the configuration of “θ.”", "[0043] Specifically, the cross-sectional view of FIG. 3B shows that the scan line 310 in the present embodiment is manufactured by the first metal layer, the data line 320 is manufactured by the second metal layer, and the auxiliary electrode 350 and the shielding electrode 360 are both manufactured by the third metal layer.", "In other words, the manufacturing sequence of the first substrate 300 is different from the manufacturing sequence of the first substrate 110 .", "[0044] Additionally, in the first substrate 300 , the auxiliary electrode 350 and the pixel electrode 340 belong to different films and are disposed on different planes.", "Therefore, when a voltage is applied to the pixel electrode 340 , the FFE is generated between the auxiliary electrode 350 and the pixel electrode 340 .", "Similarly, a corresponding FFE is generated between the shielding electrode 360 and the pixel electrode 340 .", "Thus, when the first substrate 300 applies the manufacturing method of the LCD panel described in the previous embodiment, the LC layer of the LCD panel can have the multi-domain alignment.", "In other words, the application of the first substrate 300 in the above-mentioned manufacturing method gives rise to the increase in the response rate of the LC molecules in the LCD panel and the elevation in display quality of the LCD panel.", "[0045] In light of the foregoing, different curing voltages are applied respectively to the scan lines and the data lines for directly supplying the curing voltages to the pixel electrode according to the present invention.", "Thereby, the PSA manufacturing process can be performed on the LCD panel without the dispositions of the fine slits and the alignment protrusions.", "As such, the LCD panel of the present invention has good display brightness, and the response rate of the LC molecules in the LCD panel remains satisfactory.", "In general, the manufacturing method of the LCD panel of the present invention improves the quality of the LCD panel.", "[0046] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention.", "In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents." ]
FIELD The present disclosure relates to a check ball valve assembly, and more particularly to a check ball valve assembly having a check ball guide for regulating fluid flow from multiple sources and supplying fluid to a single outlet. BACKGROUND The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art. In pressurized fluid systems, check ball valves are used to regulate fluid flow by allowing flow in one direction while blocking flow in the opposite direction. Typically, a check ball valve includes a check ball and a ball seat. When pressurized fluid flows in the direction away from the ball seat, the check ball is forced off the ball seat and the fluid flows between the check ball and the inner surface of the fluid passage. When the pressurized fluid flows toward the ball seat, the check ball is forced against the ball seat, sealing off any opening for fluid to pass around the ball. The ball is further contained in the fluid passage by a cage or other obstruction that keeps the ball from traveling into an outlet passage while otherwise providing an open cross-sectional area to allow the pressurized fluid to flow to the outlet passage. Some pressurized fluid systems may require multiple pressurized fluid sources for the purpose of, for example, backing-up a failed pressurized fluid source. When incorporating multiple pressurized fluid sources that feed a single fluid outlet, it may be desirable to prevent fluid flow into the secondary, non-pressurized fluid source when the primary fluid source is pressurized. The same protection may be required when the primary fluid source is not functioning and the secondary source is pressurized. Previously, a system capable of these functions requires two check ball valves to provide backflow prevention into the non-pressurized fluid source. The two check ball valves require twice the packaging space as a single check ball valve. Furthermore, the two check ball valves would not coordinate directly with each other and may require additional time for the check ball valves to perform their functions. Additional parts and manufacturing steps also increase the cost of the system while decreasing its reliability. While these fluid systems are effective, there is room in the art for an apparatus for controlling the flow of pressurized fluid from multiple sources to a single outlet. SUMMARY A ball check valve assembly for regulating fluid flow from a plurality of fluid pressure sources according to the principles of the present invention is provided. In one embodiment, the check ball valve assembly includes a check ball and a first fluid passage in communication with a first of the plurality of fluid pressure sources. The first fluid passage includes a check ball seat. The assembly further includes a second fluid passage in communication with a second of the plurality of fluid pressure sources. The second fluid passage intersects the first fluid passage and includes a check ball seat. The assembly further includes a third fluid passage in communication with the first and second fluid passages. The third fluid passage receives fluid flow from one of the first and second fluid passages. The assembly further includes an intersection fluid passage in communication with the first, second and third fluid passages and a check ball guide disposed in the intersection fluid passage. In one aspect of the present invention, the check ball seat of the first fluid passage has a smaller inner diameter than the diameter of the check ball. In another aspect of the present invention, the check ball seat of the second fluid passage has a smaller inner diameter than the diameter of the check ball. In yet another aspect of the present invention, the check ball is disposed in at least one of a first position, a second position, and moving between the first and second positions wherein the first position is adjacent to the check ball seat of the first fluid passage, the second position is adjacent to the check ball seat of the second fluid passage. In yet another aspect of the present invention, the intersection fluid passage includes an inner surface. The check ball guide includes an arcuate portion disposed on the inner surface of the intersection fluid passage. In yet another aspect of the present invention, the arcuate portion includes a first end and a second end wherein the first end is disposed proximate the first fluid passage and the second end is disposed proximate the second fluid passage. In yet another aspect of the present invention, the check ball guide includes an arcuate portion having a first end and a second end, wherein the first end is disposed proximate the first fluid passage and the second end is disposed proximate the second fluid passage, and wherein the arcuate portion bisects the intersection fluid passage. In yet another aspect of the present invention, the check ball valve assembly further includes a check ball guide insert. The check ball insert includes the third fluid passage and the check ball guide. In yet another aspect of the present invention, the check ball guide insert further includes a flexible retention tab. In yet another aspect of the present invention, the check ball valve assembly further includes a retention tab. The check ball guide insert further includes a notch corresponding to a retention tab of the check ball valve assembly. In yet another aspect of the present invention, the first fluid passage is provided with fluid pressure from a first fluid pump and the second fluid passage is provided with fluid pressure from a second fluid pump. Further objects, aspects and advantages of the present disclosure will become apparent by reference to the following description and appended drawings wherein like reference numbers refer to the same component, element or feature. DRAWINGS The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way; FIG. 1 is a schematic of an exemplary pressurized fluid passage system having a check ball fluid assembly according to the present disclosure; FIG. 2 is a cross-section view of an example of the check ball fluid assembly according to the present disclosure; FIG. 3 is a cross-section of another example of the check ball fluid assembly having an exemplary check ball guide insert according to the present disclosure; FIG. 4 is front view of an example of a check ball guide insert according to the present disclosure; FIG. 5 is a perspective view of another example of a check ball guide insert according to the present disclosure; FIG. 6 is a cross-section view of the check ball guide insert shown in FIG. 5 according to the present disclosure; FIG. 7 is a perspective view of another example of a check ball guide insert according to the present disclosure; FIG. 8 is a perspective view of another example of a check ball guide insert according to the present disclosure; FIG. 9 is a front view of the check ball guide insert shown in FIG. 8 ; FIG. 10 is a perspective view of another example of a check ball guide insert according to the present disclosure; and FIG. 11 is a perspective view of another example of a check ball guide insert according to the present disclosure. DETAILED DESCRIPTION The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. Referring to the drawings, wherein like reference numbers refer to like components, in FIG. 1 a schematic of an exemplary embodiment of a fluid passage system 10 is illustrated. The fluid passage system 10 includes a first source of pressurized fluid 12 and a second source of pressurized fluid 14 . The first and second sources of pressurized fluid 12 and 14 may include, for example, positive displacement pumps, hydraulic circuits having pressurized fluid flow, pressure regulation valves, accumulators, or any other source of pressurized fluid. The first source of pressurized fluid 12 communicates a fluid to a ball check valve assembly 16 via a first fluid passage 18 and the second source of pressurized fluid 14 communicates a fluid to the ball check valve assembly 16 via a second fluid passage 20 . The ball check valve assembly 16 is operable to selectively communicate fluid flow from one of the first and second fluid sources 12 and 14 to a fluid output 22 via a third fluid passage 24 . The fluid output 22 may be, for example, a hydraulic fluid control circuit for a transmission. The ball check valve assembly 16 generally includes a junction of three valve fluid passages including a first fluid valve passage 26 , a second fluid valve passage 28 , and a third fluid valve passage 30 . The first fluid valve passage 26 is in communication with the first fluid passage 18 . The second fluid valve passage 28 is in communication with the second fluid passage 20 . The third fluid valve passage 30 is in communication with the third fluid passage 24 . The first, second, and third fluid valve passages 26 , 28 , and 30 each communicate with each other at an intersection 32 . A check ball 34 is disposed within the first, second, and third fluid valve passages 26 , 28 , and 30 . The check ball 34 is contained in the first fluid valve passage 28 by a first check ball seat 36 disposed at the connection between the first fluid passage 18 and the first fluid valve passage 26 . The check ball 34 is contained in the second fluid valve passage 28 by a second check ball seat 38 disposed at the connection between the second fluid passage 20 and the second fluid valve passage 28 . The arrangement prevents the check ball 34 from traveling beyond the first and second check ball seats 36 , 38 and into the first and second fluid sources 12 , 14 . A check ball guide 40 is disposed either at the intersection 32 or within the third fluid valve passage 30 . The check ball guide 40 operates, upon pressurization of either the first or second fluid passages 18 , 20 , to deflect the check ball 34 into the non-pressurized first or second fluid passage 18 , 20 while allowing the pressurized fluid to pass through the check ball guide 40 to the third fluid passage 24 . Referring now to FIG. 2 , a cross-section of an exemplary embodiment of the check ball valve assembly 16 is illustrated. The first fluid passage 18 is shown in communication with the first valve fluid passage 26 . The first check ball seat 36 is disposed at the connection of the first fluid passage 18 and the first valve fluid passage 26 . The second fluid passage 20 is shown in communication with the second valve fluid passage 28 . The second check ball seat 38 is disposed at the connection of the first fluid passage 20 and the first valve fluid passage 28 . The fluid passages 18 , 20 have a smaller diameter than the valve fluid passages 26 , 28 . The check ball seats 36 , 38 form a portion of a conical surface to join the inner surfaces of the fluid passages 18 , 20 to the inner surfaces of the valve fluid passages 26 , 28 . The check ball 34 is disposed in the valve fluid passages 26 , 28 and has a larger diameter than the fluid passages 18 , 20 . The check ball 34 travels between the first and second check ball seats 36 , 38 , as will be described in greater detail below. The check ball guide 40 is disposed in the intersection 32 or in the third fluid passage 24 . In the example shown, the check ball guide 40 is a gradual reduction in the diameter of the intersection 32 or third fluid passage 24 in an arc from a first end 40 A of the ball check guide 40 to a second end 40 B of the ball check guide 40 . The first end 40 A is disposed proximate a surface 32 A opposite the second valve fluid passage 28 . The second end 40 B of the check ball guide 40 is disposed proximate a surface 32 B which is adjacent the second valve fluid passage 28 . When the first fluid source 12 is pressurized, the pressurized fluid forces the check ball 34 from a first position in the check ball seat 36 and carries the check ball 34 through the first valve fluid passage 26 towards the third valve fluid passage 30 . Before the check ball 34 passes into the third valve fluid passage 30 , the check ball 34 enters the intersection 32 containing the check ball guide 40 . The check ball 34 is deflected or guided by the check ball guide 40 into the second valve fluid passage 28 and is propelled further into a second position in the second check ball seat 38 by the pressurized fluid of the first fluid source 12 . The reduced diameter of the check ball guide 40 prevents the check ball 34 from entering the third fluid passage 24 . In addition, due to the curved or arcuate shape of the ball check guide 40 from the end 40 A to the end 40 B, the check ball 34 is prevented from seating or blocking the third fluid passage 24 . After the check ball 34 is seated in the second check ball seat 38 , the pressurized fluid flows without obstruction to the third fluid passage 24 . The check ball 34 actuation is repeated in reverse when the second fluid source 14 becomes pressurized and the first fluid source 12 is depressurized. The pressurized fluid from the second fluid source 14 forces the check ball 34 from the second position in the second check ball seat 38 and carries the check ball 34 through the second valve fluid passage 28 towards the third valve fluid passage 30 . Before the check ball 34 passes into the third valve fluid passage 30 , the check ball 34 enters the intersection 32 containing the check ball guide 40 . The check ball 34 is deflected or guided by the check ball guide 40 into the first valve fluid passage 26 and is propelled further into the first position in the first check ball seat 36 by the pressurized fluid of the first fluid source 12 . Referring now to FIG. 3 , a cross-section of another example of the check ball valve assembly 16 ′ is illustrated. The check ball valve assembly 16 ′ is similar to the check ball valve assembly 16 described in FIG. 1 and therefore like components are indicated by like reference numbers. However, the check ball guide 40 of the check ball valve assembly 16 has been replaced with a check ball guide insert 42 . The check ball guide insert 42 is a replaceable part that may be readily replaced when desired. The check ball guide insert 42 has a hollow cylindrical body 43 and is disposed in the third fluid passage 24 . The check ball guide insert 42 includes a first open end 45 that communicates with the fluid passages 26 and 28 and a second open end 47 that communicates with the fluid passage 24 . The check ball guide insert 42 includes a check ball guide 41 and a check ball guide retention tab 44 . The retention tab 44 is disposed on the outer periphery of the check ball guide insert 42 . The retention tab 44 is flexible and coordinates with a groove 16 A located within the third fluid passage 24 of the ball valve assembly 16 ′ to lock the check ball guide insert 42 into the ball valve assembly 16 ′. As the check ball guide insert 42 is placed inside the check ball valve assembly 16 , the flexible retention tab 44 initially deflects to clear the inner diameter of the check ball valve assembly 16 and snaps into the groove 16 A when the check ball guide insert 42 is seated in the check ball valve assembly 16 . However, it should be appreciated that other methods and mechanisms for retaining the check ball guide insert 42 into the ball valve assembly 16 ′ may be employed without departing from the scope of the present invention. Referring now to FIGS. 4-6 , the check ball guide 41 is defined by an interior surface 46 within the hollow body 43 . More specifically, the check ball guide 41 is defined by a pair of arcuate projections 48 A, 48 B disposed opposite each other on the inner surface 46 near the open end 45 . The check ball guide 41 effectively forms a track which receives and redirects the check ball 34 while allowing the pressurized fluid to flow through the check ball guide 41 between the arcuate projections 48 A, 48 B and into the third fluid passage 24 . The check ball guide insert 42 prevents the check ball 34 from entering the third fluid passage 24 . In addition, the check ball guide insert 42 prevents the check ball 34 from seating or blocking the third fluid passage 24 . Turning to FIG. 7 , an alternate embodiment of a check ball guide insert is generally indicated by reference number 50 . The check ball guide insert 50 includes a check ball guide 52 and a retention feature 54 having an alignment indentation 56 and a retention tab receiving hole 58 . More specifically, the alignment indentation 56 receives an orientation and retention tab of a ball valve assembly (not shown). As the check ball guide insert 52 is moved into position, the retention tab is deflected into the retention tab receiving hole 58 by the alignment indentation 56 . This feature provides proper orientation and retention of the check ball guide 52 when installed in the check ball valve assembly (not shown). With reference to FIGS. 8 and 9 , another example of a check ball guide insert is indicated by reference number 60 . The check ball guide insert 60 includes a check ball guide 62 , an orientation key 64 and an inside surface 66 that communicates with the third fluid passage 24 of the check ball valve assembly (not shown). The check ball guide 62 is an arcuate member that spans and bisects the inside bore 66 from a first surface 68 A of the third fluid passage 68 to a second surface 68 B of the third fluid passage 68 . The orientation key 64 is a projection on an outer surface 60 A of the check ball guide insert 60 that coordinates with a key groove of the ball valve assembly (not shown). The orientation key 64 provides proper orientation of the check ball guide 62 when installed in the check ball valve assembly. With reference to FIG. 10 , another example of a check ball guide insert is indicated by reference number 70 . The check ball guide insert 70 includes a check ball guide 72 , an orientation key 74 and an inside surface 76 that communicates with the third fluid passage 24 of the check ball valve assembly (not shown). The check ball guide 72 is an arcuate member that spans and bisects the inside bore 76 . The orientation key 74 is a projection on an outer surface 70 A of the check ball guide insert 70 that coordinates with a key groove of the ball valve assembly (not shown). The orientation key 74 provides proper orientation of the check ball guide 72 when installed in the check ball valve assembly. Turning to FIG. 11 , another example of a check ball guide insert is generally indicated by reference number 80 . The check ball guide insert 80 includes a check ball guide 82 and a retention feature 84 having a pair of flexible alignment and retention tabs 84 A, 84 B. More specifically as the check ball guide insert 80 is moved into position, the alignment and retention tabs 84 A, 84 B guide a post 86 that is fixed to a check ball valve assembly (not shown). The post 86 forces the alignment and retention tabs 84 A, 84 B to flex around the post 86 and lock the check ball guide insert 80 into place. This feature provides proper orientation and retention of the check ball guide 80 when installed in the check ball valve assembly (not shown). The check ball valve assembly 16 , 16 ′ of the present invention provides a fast response valve system having fewer parts than would be required utilizing previous technology. The check ball valve assembly 16 , 16 ′ also requires less packaging space so that it can be combined with other features in a pressurized fluid system in a smaller and more compact unit. Additionally, the ability to remove and replace the check ball guide insert 42 , 50 , 60 , 70 , 80 provides for longer life of the check ball valve assembly 16 by providing the ability to replace worn or damaged parts. The description of the disclosure is merely exemplary in nature and variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.
A check ball valve assembly is used to regulate fluid flow from two separate fluid sources to a single fluid outlet. The assembly utilizes a single check ball alternating between two check ball seats in two separate fluid passages. A check ball guide is installed at the intersection of the separate fluid passages and deflects the check ball from the pressurized passage to the non-pressurized passage to prevent backflow into the fluid source.
Identify the most important claim in the given context and summarize it
[ "FIELD The present disclosure relates to a check ball valve assembly, and more particularly to a check ball valve assembly having a check ball guide for regulating fluid flow from multiple sources and supplying fluid to a single outlet.", "BACKGROUND The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.", "In pressurized fluid systems, check ball valves are used to regulate fluid flow by allowing flow in one direction while blocking flow in the opposite direction.", "Typically, a check ball valve includes a check ball and a ball seat.", "When pressurized fluid flows in the direction away from the ball seat, the check ball is forced off the ball seat and the fluid flows between the check ball and the inner surface of the fluid passage.", "When the pressurized fluid flows toward the ball seat, the check ball is forced against the ball seat, sealing off any opening for fluid to pass around the ball.", "The ball is further contained in the fluid passage by a cage or other obstruction that keeps the ball from traveling into an outlet passage while otherwise providing an open cross-sectional area to allow the pressurized fluid to flow to the outlet passage.", "Some pressurized fluid systems may require multiple pressurized fluid sources for the purpose of, for example, backing-up a failed pressurized fluid source.", "When incorporating multiple pressurized fluid sources that feed a single fluid outlet, it may be desirable to prevent fluid flow into the secondary, non-pressurized fluid source when the primary fluid source is pressurized.", "The same protection may be required when the primary fluid source is not functioning and the secondary source is pressurized.", "Previously, a system capable of these functions requires two check ball valves to provide backflow prevention into the non-pressurized fluid source.", "The two check ball valves require twice the packaging space as a single check ball valve.", "Furthermore, the two check ball valves would not coordinate directly with each other and may require additional time for the check ball valves to perform their functions.", "Additional parts and manufacturing steps also increase the cost of the system while decreasing its reliability.", "While these fluid systems are effective, there is room in the art for an apparatus for controlling the flow of pressurized fluid from multiple sources to a single outlet.", "SUMMARY A ball check valve assembly for regulating fluid flow from a plurality of fluid pressure sources according to the principles of the present invention is provided.", "In one embodiment, the check ball valve assembly includes a check ball and a first fluid passage in communication with a first of the plurality of fluid pressure sources.", "The first fluid passage includes a check ball seat.", "The assembly further includes a second fluid passage in communication with a second of the plurality of fluid pressure sources.", "The second fluid passage intersects the first fluid passage and includes a check ball seat.", "The assembly further includes a third fluid passage in communication with the first and second fluid passages.", "The third fluid passage receives fluid flow from one of the first and second fluid passages.", "The assembly further includes an intersection fluid passage in communication with the first, second and third fluid passages and a check ball guide disposed in the intersection fluid passage.", "In one aspect of the present invention, the check ball seat of the first fluid passage has a smaller inner diameter than the diameter of the check ball.", "In another aspect of the present invention, the check ball seat of the second fluid passage has a smaller inner diameter than the diameter of the check ball.", "In yet another aspect of the present invention, the check ball is disposed in at least one of a first position, a second position, and moving between the first and second positions wherein the first position is adjacent to the check ball seat of the first fluid passage, the second position is adjacent to the check ball seat of the second fluid passage.", "In yet another aspect of the present invention, the intersection fluid passage includes an inner surface.", "The check ball guide includes an arcuate portion disposed on the inner surface of the intersection fluid passage.", "In yet another aspect of the present invention, the arcuate portion includes a first end and a second end wherein the first end is disposed proximate the first fluid passage and the second end is disposed proximate the second fluid passage.", "In yet another aspect of the present invention, the check ball guide includes an arcuate portion having a first end and a second end, wherein the first end is disposed proximate the first fluid passage and the second end is disposed proximate the second fluid passage, and wherein the arcuate portion bisects the intersection fluid passage.", "In yet another aspect of the present invention, the check ball valve assembly further includes a check ball guide insert.", "The check ball insert includes the third fluid passage and the check ball guide.", "In yet another aspect of the present invention, the check ball guide insert further includes a flexible retention tab.", "In yet another aspect of the present invention, the check ball valve assembly further includes a retention tab.", "The check ball guide insert further includes a notch corresponding to a retention tab of the check ball valve assembly.", "In yet another aspect of the present invention, the first fluid passage is provided with fluid pressure from a first fluid pump and the second fluid passage is provided with fluid pressure from a second fluid pump.", "Further objects, aspects and advantages of the present disclosure will become apparent by reference to the following description and appended drawings wherein like reference numbers refer to the same component, element or feature.", "DRAWINGS The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way;", "FIG. 1 is a schematic of an exemplary pressurized fluid passage system having a check ball fluid assembly according to the present disclosure;", "FIG. 2 is a cross-section view of an example of the check ball fluid assembly according to the present disclosure;", "FIG. 3 is a cross-section of another example of the check ball fluid assembly having an exemplary check ball guide insert according to the present disclosure;", "FIG. 4 is front view of an example of a check ball guide insert according to the present disclosure;", "FIG. 5 is a perspective view of another example of a check ball guide insert according to the present disclosure;", "FIG. 6 is a cross-section view of the check ball guide insert shown in FIG. 5 according to the present disclosure;", "FIG. 7 is a perspective view of another example of a check ball guide insert according to the present disclosure;", "FIG. 8 is a perspective view of another example of a check ball guide insert according to the present disclosure;", "FIG. 9 is a front view of the check ball guide insert shown in FIG. 8 ;", "FIG. 10 is a perspective view of another example of a check ball guide insert according to the present disclosure;", "and FIG. 11 is a perspective view of another example of a check ball guide insert according to the present disclosure.", "DETAILED DESCRIPTION The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.", "Referring to the drawings, wherein like reference numbers refer to like components, in FIG. 1 a schematic of an exemplary embodiment of a fluid passage system 10 is illustrated.", "The fluid passage system 10 includes a first source of pressurized fluid 12 and a second source of pressurized fluid 14 .", "The first and second sources of pressurized fluid 12 and 14 may include, for example, positive displacement pumps, hydraulic circuits having pressurized fluid flow, pressure regulation valves, accumulators, or any other source of pressurized fluid.", "The first source of pressurized fluid 12 communicates a fluid to a ball check valve assembly 16 via a first fluid passage 18 and the second source of pressurized fluid 14 communicates a fluid to the ball check valve assembly 16 via a second fluid passage 20 .", "The ball check valve assembly 16 is operable to selectively communicate fluid flow from one of the first and second fluid sources 12 and 14 to a fluid output 22 via a third fluid passage 24 .", "The fluid output 22 may be, for example, a hydraulic fluid control circuit for a transmission.", "The ball check valve assembly 16 generally includes a junction of three valve fluid passages including a first fluid valve passage 26 , a second fluid valve passage 28 , and a third fluid valve passage 30 .", "The first fluid valve passage 26 is in communication with the first fluid passage 18 .", "The second fluid valve passage 28 is in communication with the second fluid passage 20 .", "The third fluid valve passage 30 is in communication with the third fluid passage 24 .", "The first, second, and third fluid valve passages 26 , 28 , and 30 each communicate with each other at an intersection 32 .", "A check ball 34 is disposed within the first, second, and third fluid valve passages 26 , 28 , and 30 .", "The check ball 34 is contained in the first fluid valve passage 28 by a first check ball seat 36 disposed at the connection between the first fluid passage 18 and the first fluid valve passage 26 .", "The check ball 34 is contained in the second fluid valve passage 28 by a second check ball seat 38 disposed at the connection between the second fluid passage 20 and the second fluid valve passage 28 .", "The arrangement prevents the check ball 34 from traveling beyond the first and second check ball seats 36 , 38 and into the first and second fluid sources 12 , 14 .", "A check ball guide 40 is disposed either at the intersection 32 or within the third fluid valve passage 30 .", "The check ball guide 40 operates, upon pressurization of either the first or second fluid passages 18 , 20 , to deflect the check ball 34 into the non-pressurized first or second fluid passage 18 , 20 while allowing the pressurized fluid to pass through the check ball guide 40 to the third fluid passage 24 .", "Referring now to FIG. 2 , a cross-section of an exemplary embodiment of the check ball valve assembly 16 is illustrated.", "The first fluid passage 18 is shown in communication with the first valve fluid passage 26 .", "The first check ball seat 36 is disposed at the connection of the first fluid passage 18 and the first valve fluid passage 26 .", "The second fluid passage 20 is shown in communication with the second valve fluid passage 28 .", "The second check ball seat 38 is disposed at the connection of the first fluid passage 20 and the first valve fluid passage 28 .", "The fluid passages 18 , 20 have a smaller diameter than the valve fluid passages 26 , 28 .", "The check ball seats 36 , 38 form a portion of a conical surface to join the inner surfaces of the fluid passages 18 , 20 to the inner surfaces of the valve fluid passages 26 , 28 .", "The check ball 34 is disposed in the valve fluid passages 26 , 28 and has a larger diameter than the fluid passages 18 , 20 .", "The check ball 34 travels between the first and second check ball seats 36 , 38 , as will be described in greater detail below.", "The check ball guide 40 is disposed in the intersection 32 or in the third fluid passage 24 .", "In the example shown, the check ball guide 40 is a gradual reduction in the diameter of the intersection 32 or third fluid passage 24 in an arc from a first end 40 A of the ball check guide 40 to a second end 40 B of the ball check guide 40 .", "The first end 40 A is disposed proximate a surface 32 A opposite the second valve fluid passage 28 .", "The second end 40 B of the check ball guide 40 is disposed proximate a surface 32 B which is adjacent the second valve fluid passage 28 .", "When the first fluid source 12 is pressurized, the pressurized fluid forces the check ball 34 from a first position in the check ball seat 36 and carries the check ball 34 through the first valve fluid passage 26 towards the third valve fluid passage 30 .", "Before the check ball 34 passes into the third valve fluid passage 30 , the check ball 34 enters the intersection 32 containing the check ball guide 40 .", "The check ball 34 is deflected or guided by the check ball guide 40 into the second valve fluid passage 28 and is propelled further into a second position in the second check ball seat 38 by the pressurized fluid of the first fluid source 12 .", "The reduced diameter of the check ball guide 40 prevents the check ball 34 from entering the third fluid passage 24 .", "In addition, due to the curved or arcuate shape of the ball check guide 40 from the end 40 A to the end 40 B, the check ball 34 is prevented from seating or blocking the third fluid passage 24 .", "After the check ball 34 is seated in the second check ball seat 38 , the pressurized fluid flows without obstruction to the third fluid passage 24 .", "The check ball 34 actuation is repeated in reverse when the second fluid source 14 becomes pressurized and the first fluid source 12 is depressurized.", "The pressurized fluid from the second fluid source 14 forces the check ball 34 from the second position in the second check ball seat 38 and carries the check ball 34 through the second valve fluid passage 28 towards the third valve fluid passage 30 .", "Before the check ball 34 passes into the third valve fluid passage 30 , the check ball 34 enters the intersection 32 containing the check ball guide 40 .", "The check ball 34 is deflected or guided by the check ball guide 40 into the first valve fluid passage 26 and is propelled further into the first position in the first check ball seat 36 by the pressurized fluid of the first fluid source 12 .", "Referring now to FIG. 3 , a cross-section of another example of the check ball valve assembly 16 ′ is illustrated.", "The check ball valve assembly 16 ′ is similar to the check ball valve assembly 16 described in FIG. 1 and therefore like components are indicated by like reference numbers.", "However, the check ball guide 40 of the check ball valve assembly 16 has been replaced with a check ball guide insert 42 .", "The check ball guide insert 42 is a replaceable part that may be readily replaced when desired.", "The check ball guide insert 42 has a hollow cylindrical body 43 and is disposed in the third fluid passage 24 .", "The check ball guide insert 42 includes a first open end 45 that communicates with the fluid passages 26 and 28 and a second open end 47 that communicates with the fluid passage 24 .", "The check ball guide insert 42 includes a check ball guide 41 and a check ball guide retention tab 44 .", "The retention tab 44 is disposed on the outer periphery of the check ball guide insert 42 .", "The retention tab 44 is flexible and coordinates with a groove 16 A located within the third fluid passage 24 of the ball valve assembly 16 ′ to lock the check ball guide insert 42 into the ball valve assembly 16 ′.", "As the check ball guide insert 42 is placed inside the check ball valve assembly 16 , the flexible retention tab 44 initially deflects to clear the inner diameter of the check ball valve assembly 16 and snaps into the groove 16 A when the check ball guide insert 42 is seated in the check ball valve assembly 16 .", "However, it should be appreciated that other methods and mechanisms for retaining the check ball guide insert 42 into the ball valve assembly 16 ′ may be employed without departing from the scope of the present invention.", "Referring now to FIGS. 4-6 , the check ball guide 41 is defined by an interior surface 46 within the hollow body 43 .", "More specifically, the check ball guide 41 is defined by a pair of arcuate projections 48 A, 48 B disposed opposite each other on the inner surface 46 near the open end 45 .", "The check ball guide 41 effectively forms a track which receives and redirects the check ball 34 while allowing the pressurized fluid to flow through the check ball guide 41 between the arcuate projections 48 A, 48 B and into the third fluid passage 24 .", "The check ball guide insert 42 prevents the check ball 34 from entering the third fluid passage 24 .", "In addition, the check ball guide insert 42 prevents the check ball 34 from seating or blocking the third fluid passage 24 .", "Turning to FIG. 7 , an alternate embodiment of a check ball guide insert is generally indicated by reference number 50 .", "The check ball guide insert 50 includes a check ball guide 52 and a retention feature 54 having an alignment indentation 56 and a retention tab receiving hole 58 .", "More specifically, the alignment indentation 56 receives an orientation and retention tab of a ball valve assembly (not shown).", "As the check ball guide insert 52 is moved into position, the retention tab is deflected into the retention tab receiving hole 58 by the alignment indentation 56 .", "This feature provides proper orientation and retention of the check ball guide 52 when installed in the check ball valve assembly (not shown).", "With reference to FIGS. 8 and 9 , another example of a check ball guide insert is indicated by reference number 60 .", "The check ball guide insert 60 includes a check ball guide 62 , an orientation key 64 and an inside surface 66 that communicates with the third fluid passage 24 of the check ball valve assembly (not shown).", "The check ball guide 62 is an arcuate member that spans and bisects the inside bore 66 from a first surface 68 A of the third fluid passage 68 to a second surface 68 B of the third fluid passage 68 .", "The orientation key 64 is a projection on an outer surface 60 A of the check ball guide insert 60 that coordinates with a key groove of the ball valve assembly (not shown).", "The orientation key 64 provides proper orientation of the check ball guide 62 when installed in the check ball valve assembly.", "With reference to FIG. 10 , another example of a check ball guide insert is indicated by reference number 70 .", "The check ball guide insert 70 includes a check ball guide 72 , an orientation key 74 and an inside surface 76 that communicates with the third fluid passage 24 of the check ball valve assembly (not shown).", "The check ball guide 72 is an arcuate member that spans and bisects the inside bore 76 .", "The orientation key 74 is a projection on an outer surface 70 A of the check ball guide insert 70 that coordinates with a key groove of the ball valve assembly (not shown).", "The orientation key 74 provides proper orientation of the check ball guide 72 when installed in the check ball valve assembly.", "Turning to FIG. 11 , another example of a check ball guide insert is generally indicated by reference number 80 .", "The check ball guide insert 80 includes a check ball guide 82 and a retention feature 84 having a pair of flexible alignment and retention tabs 84 A, 84 B. More specifically as the check ball guide insert 80 is moved into position, the alignment and retention tabs 84 A, 84 B guide a post 86 that is fixed to a check ball valve assembly (not shown).", "The post 86 forces the alignment and retention tabs 84 A, 84 B to flex around the post 86 and lock the check ball guide insert 80 into place.", "This feature provides proper orientation and retention of the check ball guide 80 when installed in the check ball valve assembly (not shown).", "The check ball valve assembly 16 , 16 ′ of the present invention provides a fast response valve system having fewer parts than would be required utilizing previous technology.", "The check ball valve assembly 16 , 16 ′ also requires less packaging space so that it can be combined with other features in a pressurized fluid system in a smaller and more compact unit.", "Additionally, the ability to remove and replace the check ball guide insert 42 , 50 , 60 , 70 , 80 provides for longer life of the check ball valve assembly 16 by providing the ability to replace worn or damaged parts.", "The description of the disclosure is merely exemplary in nature and variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure.", "Such variations are not to be regarded as a departure from the spirit and scope of the disclosure." ]
FIELD OF THE INVENTION This invention relates to preparation and its use of derivatization reagent for detecting L-carnitine or D-carnitine. BACKGROUND OF THE INVENTION L-carnitine has a variety of physiological functions, which the basic one is to “transport” long-chain fatty acids into mitochondria via mitochondrial membrane where the β oxidation happens. L-carnitine is essential to fatty acid metabolism that once the synthesis of carnitine is blocked in body, or carnitine is degraded or excreted excessively, or the function of carnitine transferase decreases or losses, disturbance of lipid metabolism occurs which affects energy supply and leads to many diseases. Typical extraction method for natural L-carnitine is extracting from beef which is reported by Cater in 1952. However because the absolute content of L-carnitine is very low in meat, and the choline existing in gravy which is very similar in structure makes it is difficult to separate them, the direct extracting method is complicated, with low yield and high price. Therefore, it is not easy to get abundant natural L-carnitine. Currently, L-carnitine for medicinal use is usually synthesized artificially. Usually, separation of racemic compounds is used for L-carnitine synthesis. The raw materials are cheap and easy to get, the process is easy to industrialize. However, because the defects of traditional chemical resolution, D-isomer can not be removed completely, the synthetic L-carnitine is not absolutely laevorotatory, but contains D-carnitine. Natural carnitine is L-carnitine, and only L-carnitine is physiological active is a competitive inhibitior of carnitine acetyl transferase (CAT) and carnitine palmityl transferase (PTC). Therefore about 10% patients suffered myasthenia gravis after taking the DL-carnitine (Martindale: the Extra Pharmacopoeia (33th): 1356). Therefore taking drug safety into consideration, it's necessary to strictly control the content of the D-carnitine in the chemical synthetic process. Currently, the content of D-Carnitine is detected by specific rotation which is lack of accuracy. In order to detect accurately the content of D-carnitine in L-carnitine products, and provide much safer and more effective drugs, health products and food, it is necessary to develop a method to detect the content of D-carnitine in L-carnitine products which is more accurate and sensitive. SUMMARY OF THE INVENTION One object of this invention is to provide a reagent for detecting the content of L-carnitine (or D-carnitine) and its preparation. The preparation method disclosed in the present invention is simple, economical. The reagent produced by this method is stable during preservation and is easy to use. The second object of this invention is to provide a method to detect the content of L-carnitine (or D-carnitine) in active pharmaceutical ingredients of L-carnitine or D-carnitine, and in various pharmaceutical preparations or biological agents, health care products, cosmetics, body fluids and various food products which contain L-carnitine or/and D-carnitine. The detection method disclosed in the present invention has high sensitivity and is convenient and efficient. The present invention discloses an optically pure derivatization reagent of formula (I) for detecting the content of L-carnitine (or D-carnitine): wherein, the carbon atom marked with an asterisk is the chiral carbon atom; the compounds in the present invention are chiral compounds having pure optical active, the D- or L-compound; R represents C1-C6 straight-chain or branched alkyl groups, C6-C10 aryl groups, C2-C6 straight-chain or branched alkenyl or alkynyl groups or C3-C6 cycloalkyl groups; and X represents a halogen atom. The compound of formula (I) used in the present invention, wherein R represents methyl, ethyl, isopropyl, butyl or benzyl, and X represents Cl or Br. Preferably, the present invention discloses (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride as the derivatization reagent for detecting the content of L-carnitine or D-carnitine. The derivatization reagents for detecting the content of L-carnitine or D-carnitine disclosed in the present invention, preferably, are crystalline solid of optically pure compound of formula (I), which is more stable, difficulty decomposed, and easy to preserve comparing to its solution. The crystalline solid of optically pure compound of formula (I) in the present invention is recrystal with suitable solvent; the said solvent is selected from: ether, propyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, acetonitrile, propionitrile, ethyl acetate, n-hexane, dichloromethane, chloroform, or the mixture of any two or more solvents above. The solvent for recrystallisation of optically pure compound of formula (I) is preferably acetonitrile. The present invention also discloses using the optically pure compound of formula (I) as a derivatization reagent, which the preparation is dissolving the optically pure compound of formula (I) and its crystalline in solvents to form solutions with certain concentration, said solvent is selected from: ether, propyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, acetonitrile, propionitrile, ethyl acetate, n-hexane, dichloromethane, chloroform, or the mixture of any two or more solvents above. The concentration of the solution is 0.01˜100 mg/ml. Specially preferably, the solvent is acetonitrile and the concentration of the solution is 1-10 mg/ml. The crude active ingredient of formula (I) is produced by the steps below: (+) or (−)α-methyl-6-methoxy-2-naphthyl acetic acid is hydrolyzed, and then the phenolichydroxyl group is combined with halohydrocarbon, the product forms crude acylhalide by acylation. The present invention also discloses preparation of the crystalline solid of optically pure compound of formula (I) that the crude acylhalide is recrystallised with suitable solvent to form the crystalline solid. The said solvent is selected from ether, propyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, acetonitrile, propionitrile, ethyl acetate, n-hexane, dichloromethane, chloroform, or the mixture of any two or more solvents above. The solvent for recrystallisation of optically pure compound of formula (I) is preferably acetonitrile, so that the crystalline solid obtained has high optical purity, and can be stably preserved. The present invention discloses the crystalline of optically pure compound of formula (I), (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride, which has the characteristic of white and needle crystalline, m.p 92.3˜93.5° C.; X-Ray data: diffraction angle (2θ) is 6.579 (d=13.4231, I/I 0 =54.4), 10979 (d=8.0522, I/I 0 =34.1), 13.218 (d=6.6925, I/I 0 =72.2), 13.499 (d=6.5539, I/I 0 =45.8), 18.222 (d=4.8646, I/I 0 =21.2), 18.780 (d=4.7211, I/I 0 =100.0), 19.901 (d=4.4577, I/I 0 =21.7), 21.619 (d=4.1072, I/I 0 =26.2), 22.100 (d=4.0188, I/I 0 =75.3), 27.139 (d=3.2830, I/I 0 =19.0), 47.681 (d=1.9057, I/I 0 =15.0); IR: 3414.5 cm −1 , 2983.2 cm −1 , 1786.2 cm −1 , 1605.0 cm −1 , 1390.6 cm −1 , 1270.4 cm −1 , 1183.1 cm −1 , 823.8 cm −1 , 701.6 cm −1 , 7412 cm −1 ; 1 HNMR (CD3COCD3, 500 MHz): 1.66 (m, 3H), 3.78 (s, 3H), 4.46 (m, 1H), 7.19 (m, 1H), 7.29 (m, 1H), 7.43 (m, 1H), 7.82 (m, 1H), 7.83 (s, 1H), 7.85 (s, 1H); elemental analysis: C %: 67.76 (theoretical value is 67.61), H %: 5.25 (5.27). MS: the molecular weight is 248, 250, it is the isotopic peak of chlorine, m/z 185 is the base peak with the abundances of 100%, from which can be supposed as the fragment ion of formula The present invention discloses a method for detecting the content of L-carnitine or D-carnitine in a sample; the detection includes the following steps: (1) Prepare the test sample solution containing proper amount of L-carnitine (or D-carnitine) and the control solution containing DL-carnitine. (2) Mix proper amount of derivative reagent of the present invention and the test sample solution containing L-carnitine (or D-carnitine), and let them react to afford L-carnitine (or D-carnitine) derivatives. (3) Apply HPLC to detect and calculate the content of L-carnitine (or D-carnitine) in the sample. The present invention discloses a method for detecting the content of L-carnitine or D-carnitine in a sample, wherein the detection includes the following steps: (1) Prepare the derivatization reagent solution: D-type or L-type optical pure compound of formula (I) of any of claims 1 to 5 is dissolved in solvent to form a 0.01˜100 mg/ml solution under the dark conditions, wherein the compound of formula (I) is preferably (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride, and the solvent is preferably acetonitrile; the concentration of solution is preferably from 1 to 10 mg/ml. (2) Prepare of the test solution of L-carnitine or D-carnitine, and control solution of DL-carnitine; (3) Derived reagent of step (1) is mixed and reacted with test solution and control solution of step (2) respectively in a airtight vessel, in the present of solvent at 20° C.˜95° C. in a water bath for 20 min to 180 min; (4) HPLC is applied to separate and detect the reacted test solution and control solution, the content of L-carnitine (or D-carnitine) in test solution is calculated by external standard method. Detailed detection also includes: (1) Chromatographic conditions: The octadecyl silane bonded silica is taken as a filler, and triethylamine buffer (phosphate 8 ml, triethylamine, 15 ml, water 1500 ml)-tetrahydrofuran is taken as mobile phase for gradient elution. Excitation wavelength is from 230 nm to 260 nm and emission wavelength is from 340 nm to 380 nm. (2) Preparation of test solution: test sample is precisely weighed and dissolved in water to form 0.1 μg/ml˜3.0 μg/ml solution which is the test solution. (3) Preparation of control solution: DL-carnitine is precisely weighed and desolved in water to form 0.2 μg/ml˜6.0 μg/ml solution which is the control solution. (4) Derivatization reaction: 30 μl of control solution and test solution is put in 5 ml volumetric flask respectively, for, each one, 0.01 mol/L˜0.5 mol/L of carbonate buffer solution is added in, proper amount of pyridine acetonitrile solution (per 1 ml acetonitrile contains 1 μl˜50 μl of pyridine) is mixed with derivatization reagent solution of the present invention, sealed and reacted at 20° C.˜95° C. in warm water bath, which is diluted with acetic acid buffer to the scale, shaken and tilted right after removing from the bath. (5) Content detection: the same amount of reacted test sample and the control solution is injected in HPLC respectively, chromatograms is recorded and the content of L-carnitine (or D-carnitine) in test solution is calculated by external standard method. L-carnitine (or D-carnitine) content detection of the present invention, wherein the above mentioned chromatographic conditions of step (1) comprise a mobile phase which is a mix of the triethylamine buffer (phosphate 8 ml, triethylamine, 15 ml, water 1500 ml) and tetrahydrofuran. The pH value of triethylamine buffer solution is 2.0%˜9.0. The gradient of the two components is 0-10 min, when the concentration of triethylamine buffer is 70%˜90%, and that of THF is 30%˜10%; it is 10%˜11 min, when the concentration of triethylamine buffer is from 70% to 30%˜90% to 30%, and that of THF is from 30% to 70%˜10% to 70%; it is 11˜18 min, when the concentration of triethylamine buffer is 30%, and that of tetrahydrofuran is 70%; it is 18˜19 min, when the concentration of triethylamine buffer is from 30% to 70%˜30% to 90%, and that of THF is from 70% to 30%˜70% to 10%; it is 19˜25 min, when the concentration of triethylamine buffer is 70%˜90%, and that of THF is 30%˜10%. L-carnitine (or D-carnitine) content detection of the present invention, wherein control solution of step (3) is prepared in detail that DL-carnitine 2 mg˜60 mg is weighted precisely and dissolved with water in a 100 mL of volumetric flask, volume, 10 ml of which is precisely pipetted into a 100 ml of volumetric flask, added water to volume. It is the control solution. When the concentration of L-carnitine (or D-carnitine) is 0.1 μg/ml˜3.0 μg/ml, there is a good linear relationship, which the linear correlation coefficient r equals to 0.9991 and the recovery is 100.6%. L-carnitine (or D-carnitine) content detection of the present invention, wherein derivatization reagent concentration of step (4) is 0.01˜100 mg/ml, preferably is 1-10 mg/ml, most preferably is 5 mg/ml. L-carnitine (or D-carnitine) content detection of the present invention, wherein carbonate buffer solution of step (4) prepared in detail that 4.2 g sodium bicarbonate is dissolved in 900 ml water, and pH value is adjusted with 5 mol/L of hydrogen sodium to 7.0˜12.0, added water to 1000 mL. L-carnitine (or D-carnitine) content detection of the present invention, wherein the quantity added in carbonate buffer solution of step (4) is 5 μl to 500 μl. L-carnitine (or D-carnitine) content detection of the present invention, wherein the reaction temperature of step (4) is 20° C.-95° C., and reaction time is 20 min˜180 min. L-carnitine (or D-carnitine) content detection of the present invention, wherein the acetate buffer solution of step (4) is prepared in detail that 3.0 mL glacial acetic acid is dissolved with 900 mL water, and pH value is adjusted with 5 mol/L of sodium hydroxide solution to 2.0˜7.0, and added water to 1000 mL. The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of L-carnitine and/or D-carnitine in various pharmaceutical preparations or biological agents, health care products, cosmetics, body fluids and various food products which contain L-carnitine or/and D-carnitine, such as: L-carnitine API, injection, oral liquid, tablets, slimming capsules, drinks and etc. The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of carnitine in the tissue and plasma of various mammals, including human. The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of carnitine in various edible plant and animal food. Such as: pig, cattle, sheep, chicken, shrimp, fish, eggs, vegetables, fruits and etc. The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of carnitine in various animal feed. The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of carnitine in various plant nutrients. The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the optical purity other chiral amino acids. The description of the code used in the invention: D-: D-isomer L-: L-isomer IR: infrared absorption spectroscopy HNMR: H Nuclear Magnetic Resonance MS: mass spectrometry HPLC: high performance liquid chromatography (+) MNPC: (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride (+) ENPC: (+)α-methyl-6-ethoxy-2-naphthyl acetyl chloride (+) PNPC: (+)α-methyl-6-isopropoxy-2-naphthyl acetyl chloride (+) BUNPC: (+)α-methyl-6-butoxy-2-naphthyl acetyl chloride (+) BNPC: (+)α-methyl-6-benzoxy-2-naphthyl acetyl chloride BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is the excitation spectrum of detecting the content of L-carnitine (or D-carnitine); FIG. 2 is the emission spectrum of detecting the content of L-carnitine (or D-carnitine); FIG. 3 is the HPLC of detecting the content of L-carnitine [L-carnitine (tR=5.139 min)]; FIG. 4 is the HPLC of detecting the content of L-carnitine[D-carnitine (tR=4.389 min), L-carnitine (tR=5.136 min)]. DETAILED DESCRIPTION OF THE INVENTION The following implementations are used to explain the present invention, but not limit the scope of this invention. Example 1 Preparation of (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride ((+) MNPC) 4.6 g (+)α-methyl-6-methoxy-2-naphthyl acetic acid and 50 ml THF was added in a 100 ml of single neck bottle, cooled with ice water, stirred with magnetic force, added 2 ml SOCl2, added proper amount of pyridine, reacted for 6 h, dried by rotary, added 20 ml acetonitrile, cooled to give faint yellow solid, recrystallised with 15 ml acetonitrile to give white needle crystal. Dried under vacuum to give 2.87 g of product, yield 57%, m.p 92.3-93.5° C. IR: 3414.5 cm −1 , 2983.2 cm −1 , 1786.2 cm −1 , 1605.0 cm −1 , 1390.6 cm −1 , 1270.4 cm −1 , 1183.1 cm −1 , 832.8 cm −1 , 701.6 cm −1 , 472.2 cm −1 . 1HNMR ((CD3COCD3, 500 MHz): 1.66 (m, 3H), 3.78 (s, 3H), 4.46 (m, 1H), 7.19 (m, 1H), 7.29 (m, 1H), 7.43 (m, 1H), 7.82 (m, 1H), 7.83 (s, 1H), 7.85 (s, 1H); X-Ray data: diffraction angle (2θ) is 6.579 (d=13.4231, I/I 0 =54.4), 10979 (d=8.0522, I/I 0 =34.1), 13.218 (d=6.6925, I/I 0 =72.2), 13.499 (d=6.5539, I/I 0 =45.8), 18.222 (d=4.8646, I/I 0 =21.2), 18.780 (d=4.7211, I/I 0 =100.0), 19.901 (d=4.4577, I/I 0 =21.7), 21.619 (d=4.1072, I/I 0 =26.2), 22.100 (d=4.0188, I/I 0 =75.3), 27.139 (d=3.2830, I/I 0 =19.0), 47.681 (d=1.9057, I/I 0 =15.0); MS: MW 248, 250, it is the isotopic peak of chlorine, m/z 185 is the base peak with the abundances of 100%, from which can be supposed as the fragment ion of formula Elemental analysis: C %: 67.76 (theoretical value is 67.61), H %: 5.25 (5.27) Example 2 Preparation of (+)α-methyl-6-ethoxy-2-naphthyl acetyl chloride ((+) ENPC) Step 1 50 g (+)α-methyl-6-ethoxy-2-naphthyl acetic acid was dissolved in 205 ml glacial acetic acid, heated under reflux, added 20 ml of 36% HCl in each 30 min, reacted for 6 h. and poured into 600 g ice water, filtered, recrystallised with ethanol-water, dried to give colorless crystal (9.87 g), yield 90.5%, m.p 189.4˜191.3° C.; IR: 3411.1 cm −1 , 1701.4 cm −1 , 1632.5 cm −1 , 1606.2 cm −1 , 1509.1 cm −1 , 1384.4 cm −1 , 1189.0 cm −1 , 1147.3 cm −1 , 865.9 cm −1 , 477.8 cm −1 . 1HNMR ((CD3COCD3, 500 MHz): δ1.53 (m, 3H), 3.98 (s, 3H), 7.15 (m, 1H), 7.20 (m, 1H), 7.42 (m, 1H), 7.67 (m, 1H), 7.73 (s, 1H), 7.76 (m, 1H), 8.55 (s, 1H); Step 2 The product of step 1 (41.0 g) and KOH (32.0 g) was dissolved in 200 ml of methanol, added 35.5 ml bromoethane, heated under reflux for 2 h, added 200 ml of 5% NaOH after cooled, and reacted for 3˜4 h, added 600 ml ice water after reaction, stirred, rested and filtered, washed with water, recrystallised with 500 ml ethanol and dried at 80° C. to give product (37.2 g), yield 80.3%, m.p 151.8˜155.6; IR: 3453.5 cm −1 , 1729.6 cm −1 , 1609.5 cm −1 , 1604.5 cm −1 , 1393.7 cm −1 , 1181.9 cm −1 , 1158.4 cm −1 , 862.4 cm −1 , 481.8 cm −1 . 1HNMR ((CD3COCD3, 500 MHz): σ1.43 (m, 3H), 1.53 (m, 3H), 3.90 (m, 1H), 4.16 (m, 2H), 7.15 (m, 1H), 7.25 (m, 1H), 7.46 (m, 1H), 7.75 (s, 1H), 7.76 (s, 1H), 7.79 (s, 1H). Step 3 Formation of acyl chloride from the product of step 2 according to example 1, m.p 91.7˜92.9° C. IR: 3416.7 cm −1 , 2982.1 cm −1 , 1785.9 cm −1 , 1605.2 cm −1 , 1309.5 cm −1 , 1269.1 cm −1 , 1182.6 cm −1 , 832.8 cm −1 , 701.8 cm −1 , 472.6 cm −1 . 1HNMR ((CD3COCD3, 500 MHz): σ1.43 (m, 3H), 1.66 (m, 3H), 4.18 (m, 2H), 4.46 (m, 1H), 7.19 (m, 1H), 7.29 (m, 1H), 7.43 (m, 1H), 7.82 (m, 1H), 7.83 (s, 1H), 7.85 (s, 1H) Example 3 Preparation of (+)α-methyl-6-isopropoxy-2-naphthyl acetyl chloride ((+) PNPC) 2-bromopropane was used in step 2 according to the method of example 1 to give (+) PNPC, m.p 77.8˜79.4° C.; IR: 3416.3 cm −1 , 1784.5 cm −1 , 1604.8 cm −1 , 1390.2 cm −1 , 1270.3 cm −1 , 1182.5 cm −1 , 854.6 cm −1 , 699.2 cm −1 , 469.5 cm −1 . 1HNMR ((CD3COCD3, 500 MHz): δ 1.06 (m, 3H), 1.65 (m, 3H), 1.83 (m, 2H), 4.07 (m, 2H), 4.45 (m, 1H), 7.19 (m, 1H), 7.29 (m, 1H), 7.42 (m, 1H), 7.81 (m, 1H), 7.82 (s, 1H), 7.84 (m, 1H). Example 4 Preparation of (+)α-methyl-6-butoxy-2-naphthyl acetyl chloride ((+)BUNPC) Bromobutane was used in step 2 according to the method of example 1 to give (+) BUNPC, m.p 56.3˜57.3° C.; IR: 3415.7 cm −1 , 1785.3 cm −1 , 1605.2 cm −1 , 1468.3 cm −1 , 1392.3 cm −1 , 1268.9 cm −1 , 1178.3 cm −1 , 921.8 cm −1 , 819.9 cm −1 , 727.45 cm −1 , 747.6 cm −1 . 1HNMR ((CD3COCD3, 500 MHz): δ1.00 (m, 3H), 1.55 (m, 2H), 1.67 (m, 3H), 1.82 (m, 2H), 4.14 (m, 2H), 4.48 (m, 2H), 7.19 (m, 1H), 7.31 (m, 1H), 7.42 (m, 1H), 7.82 (m, 1H), 7.83 (s, 1H), 7.85 (m, 1H). Example 5 Preparation of (+)α-methyl-6-benzoxy-2-naphthyl acetyl chloride ((+) BNPC) Benzyl bromide was used in step 2 according to the method of example 1 to give (+) BUNPC, m.p 77.2˜79.1° C. 1HNMR ((CD3COCD3, 500 MHz): δ1.6 (d, 3H), 3.81 (m, 1H), 4.14 (m, 2H), 4.48 (m, H), 5.26 (s, 2H), 7.19 (m, 1H), 7.22 (m, 1H), 7.38 (m, 3H), 7.42 (m, 1H), 7.47 (m, 2H), 7.83 (m, 1H), 7.87 (m, 1H), 7.90 (m, 1H). Example 6 Derivatization reaction and chromatographic conditions 1. Chromatographic Conditions and Systematic Adaptability Test: Agilent 1100 HPLC; fluorescence detector; column: C18-ODS column (4.6×150 mm, 5 μm); the total flow rate: 1 ml/min; mobile phase: the triethylamine buffer (phosphate 8 ml, triethylene amine 15 ml, water 1500 ml, pH adjusted to 5.4)-tetrahydrofuran mixture, the time gradient of the following Table 1: TABLE 1 HPLC time gradient table Time Triethylamine THF (min ) buffer ( % ) (%) 0 75 25 10 75 25 11 30 70 18 30 70 19 75 25 25 75 25 Number of theoretical plates was greater than 5000, and the resolution of the peak both of L-carnitine and D-carnitine was more than 1.5. 2. Detection Wavelength The spectral scan was carried out after derivatization reaction ( FIG. 1 , 2 ). Ultimately the excitation wavelength of 234 nm and emission wavelength of 360 nm was chosen. 3. Preparation of Control Solution 20 mg DL-carnitine was precisely wighted and dissolved with water in 100 mL volumetric flask to volume, and then 10 ml solution was precisely pipetted in 100 ml volumetric flask, added water to volume. It is the control solution. 4. Derivatization Reaction: 30 μl of control solution and test solution is put in 5 ml volumetric flask respectively, for, each one, 100 μl of 0.05 mol/L carbonate buffer solution (4.2 g sodium bicarbonate was dissolved in 900 ml water, pH was adjusted to 8.4 with 5 mol/L NaOH), 100 μl of pyridine acetonitrile solution (per 1 ml acetonitrile contains 25 μl of pyridine) and 200 μl of derivatization reagent solution (0.5% (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride) is mixed, sealed and reacted at 40° C. in worm water bath for 60 min, which is diluted with acetic acid buffer (3 ml glacial acetic acid was dissolved in 900 ml water, pH was adjusted with 5 mol/L NaOH to 7.0, added water to 1000 mL) to the scale, shaken and felted right after remove from the bath. 5. Detection: 10 μl of reacted test sample and the control solution is injected in HPLC respectively, chromatograms is recorded and the content of L-carnitine (or D-carnitine) in test solution is calculated by external standard method When sample concentration of L-carnitine (or D-carnitine) is 0.33 μg/ml˜1.64 μg/ml, there was a good linear relationship, and linear correlation coefficient r equaled to 0.9991, and recovery was 100.6%. Example 7 Crystallization of the Compound of Formula (I) and the Stability of the Solution Containing the Compound An accurate content of derivatization reagent is the ensurance of accurate results. However, the compounds of formula (I) are acyl chloride which is active chemically and easily decomposed in water, it is necessary to find a proper preservation and use conditions which include choosing suitable solvent to ensure the stability of the compounds of formula (I) and decreases the detecting error The solvent is selected from ether, propyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, acetonitrile, propionitrile, ethyl acetate, and etc, the crystal, is dissolved in solvent to form solution, the stability of crystal and solution is detected together. The stability tests of 5 mg/ml of (+)α-methyl-6-methoxy-2-naphthyl chloride ((+) MNPC) solutions (dissolved in acetonitrile, acetone, ethyl acetate respectively) and relative solid crystal were carried on the experimental data was shown in table 2, table 3, table 4, and table 5. TABLE 2 Investigation of (+)MNPC solid's stability Refrigerated storage time (months) Fresh 0.5 1 2 3 6 12 (+) MNPC content (%) 99.55 99.50 99.53 99.39 99.30 99.09 98.52 (−) MNPC content (%) 0.12 0.13 0.12 0.13 0.14 0.15 0.15 Other impurities (%) 0.33 0.37 0.35 0.48 0.56 0.76 1.33 Note: storage condition, dispensed in brown glass, sealed and freeze-preserved (−15° C.) - TABLE 3 Investigation of (+)MNPC acetonitrile solution's stability Refrigerated storage time (day) Fresh 3 10 20 30 50 80 (+) MNPC content (%) 99.55 99.55 99.51 99.09 99.55 99.15 97.48 (−) MNPC content (%) 0.12 0.13 0.16 0.19 0.16 0.23 0.31 Other impurities (%) 0.33 0.32 0.33 0.72 0.29 0.62 2.21 Note: storage condition, dispensed in brown glass, sealed and freeze-preserved (−15° C.) TABLE 4 Investigation of (+)MNPC acetone solution's stability Refrigerated storage time (day) Fresh 3 10 20 30 50 80 (+) MNPC content (%) 99.55 99.04 98.64 97.33 96.21 94.83 90.51 (−) MNPC content (%) 0.12 0.15 0.17 0.21 0.24 0.42 0.73 Other impurities (%) 0.33 0.81 1.19 2.46 3.55 4.75 8.76 Note: storage condition, dispensed in brown glass, sealed and freeze-preserved (−15° C.) TABLE 5 Investigation of (+) MNPC ethyl acetate solution's stability Refrigerated storage time (day) Fresh 3 10 20 30 50 80 (+) MNPC content (%) 99.55 95.88 90.90 84.13 67.96 50.22 16.52 (−) MNPC content (%) 0.12 0.98 1.77 3.11 3.85 4.01 4.82 Other impurities (%) 0.33 3.14 7.33 12.76 28.19 45.77 78.66 Note: storage condition, dispensed in brown glass, sealed and freeze-preserved (−15° C.) It is shown in from table 2 to table 5 that solid crystal of MNPC is more stable than any solution in all samples, and in all the solutions the MNPC acetonitrile solution had the best stability which the content decreased obviously since the 60th day while others were even worse. Therefore, MNPC solid crystal has the best stability, as a derivatization reagent, it is suitable for long-term preservation and transportation; in all the solutions, the MNPC acetonitrile solution has the best stability, acetonitrile is a suitable solvent for preparing the derivatization reagent and conducting derivatives reaction. Example 8 Precise detection of the content of D-Carnitine in synthetic L-carnitine 100 mg L-carnitine was precisely weighted and dissolved with water in 100 ml of volumetric flask to volume, 10 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the sample solution; 20 mg DL-carnitine was weighted and dissolved with water in 100 ml volumetric flask to volume, and 1 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the control solution. 30 μl of control solution and sample solution was pipetted precisely respectively in 5 ml volumetric flask, for each one, 100 μl of 0.05 mol/L carbonate buffer solution (4.2 g sodium bicarbonate was dissolved in 900 ml water, pH was adjusted to 8.4 with 5 mol/L NaOH), 100 μl of pyridine acetonitrile solution (per 1 ml acetonitrile contains 25 μl of pyridine) and 200 μl of derivatization reagent solution (0.5% (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride) was mixed, sealed and reacted at 40° C. in worm water bath for 60 min, which was diluted with acetic acid buffer (3 ml glacial acetic acid was dissolved in 900 ml water, pH was adjusted with 5 mol/L NaOH to 7.0, added water to 1000 mL) to the scale, shaken and lilted right after remove from the bath. 10 μl of control solution and sample solution was pipetted and injected respectively in HPLC, chromatograph was recorded and the content of D-carnintine was calculated by external standard method The result was shown in table 6. TABLE 6 Detection of D-carnitine in synthetic L-carnitine Aver- 1 2 3 4 5 6 age RSD D-carnitine 0.99 0.97 1.00 0.98 1.00 0.98 0.99 1.22% (%) Example 9 Detection of the Content of L-Carnitine 10 mg L-carnitine was precisely weighted and dissolved with water in 100 ml of volumetric flask to volume, 1 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the sample solution; 20 mg DL-carnitine was weighted and dissolved with water in 100 ml volumetric flask to volume, and 1 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the control solution. 30 μl of control solution and sample solution was pipetted precisely respectively in 5 ml volumetric flask, for each one, 100 μl of 0.05 mol/L carbonate buffer solution (pH=8.4), 100 μl of pyridine acetonitrile solution and 100 μl of 0.5% derivatization reagent acetonitrile solution was mixed, sealed and reacted at 40° C. in worm water bath for 60 min, which was diluted with 0.05 mol/L acetic acid buffer (pH 7.0) to the scale, shaken and tilted right after remove from the bath. 10 μl of control solution and sample solution was pipetted and injected respectively in HPLC, chromatograph was recorded and the content of D-carnintine was calculated by external standard method The result was shown in table 8. TABLE 8 Detection of L-carnitine Aver- 1 2 3 4 5 6 age RSD L-carnitine 98.53 98.88 98.82 98.67 99.13 98.72 98.79 0.21% (%) Example 10 Detection of L-Carnitine and D-Carnitine in L-Carnitine API Synchronously 100 mg food containing L-carnitine was weight precisely and dissolved in 100 ml of volumetric flask to volume, 1 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the sample solution; 20 mg DL-carnitine was weighted and dissolved with water in 100 ml volumetric flask to volume, which was the control 1; and 1 ml “control 1” solution was pipetted in 100 ml volumetric flask, added water to volume, which is the control 2. 30 μl of “control 1”, “control 2” and sample solution was pipetted precisely respectively in 5 ml volumetric flask, for each one, 100 μl of 0.05 mol/L carbonate buffer solution (4.2 g sodium bicarbonate was dissolved in 900 ml water, pH was adjusted to 8.4 with 5 mol/L NaOH), 100 μl of pyridine acetonitrile solution (per 1 ml acetonitrile contains 25 μl of pyridine) and 100 μl of derivatization reagent solution (0.5% (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride) was mixed, sealed and reacted at 40° C. in worm water bath for 60 min, which was diluted with acetic acid buffer (3 ml glacial acetic acid was dissolved in 900 ml water, pH was adjusted with 5 mol/L NaOH to 7.0, added water to 1000 mL) to the scale, shaken and filted right after remove from the bath. 10 μl of control solution and sample solution was pipetted and injected respectively in HPLC, chromatograph was recorded and the content of D-carnintine was calculated by external standard method. The result was shown in table 9. TABLE 9 Detection for L-carnitine API Aver- 1 2 3 4 5 6 age RSD L-carnitine 98.01 97.75 98.57 97.83 98.19 97.64 98.00 0.35% (%) D-carnitine 0.58 0.61 0.59 0.59 0.61 0.60 0.60 2.03% (%) Example 11 Detection of the Content of L-Carnitine in Injection L-carnitine injection (5 ml: 1 g) 1 mL was pipetted precisely in 100 mL volumetric flask, added water to volume, 1 ml of the solution was pipetted precisely in 100 ml volumetric flask, added water to volume, and 5 ml of the solution was pipetted precisely in 100 ml, added water to volume. It is the sample solution. The method of example 9 was used for detection and the result was shown in table 10. TABLE 10 Detection of L-carnitine injection (labelled amount) Aver- 1 2 3 4 5 6 age RSD L-carnitine 100.55 99.81 100.19 99.72 100.3 100.39 100.16 0.33% (%) Example 12 Detection of the Content of L-Carnitine in Oral Solution L-carnitine oral solution (10 ml: 1 g) 1 mL was pipetted precisely in 100 ml volumetric flask, added water to volume, 1 ml of the solution was pipetted precisely in 100 ml volumetric flask, added water to volume, and 10 ml of the solution was pipetted precisely in 100 ml, added water to volume. It is the sample solution. The method of example 9 was used for detection and the result was shown in table 11. TABLE 11 Detection for L-carnitine oral solution (labeled amount) Aver- 1 2 3 4 5 6 age RSD L-carnitine 97.88 98.05 97.55 98.23 97.77 97.71 97.86 0.25% (%) Example 13 Detection of the Content of L-Carnitine in Slimming Capsule 20 L-carnitine slimming capsules were weighted precisely, the contents of capsules were poured out (without losing capsule shell which was weighted followed by cleaning with small brush); the contents of capsules were mixed, porphyrized, weighted properly (equaled to 10 mg L-carnitine) and put in 100 ml volumetric flask, added water and treated with ultrasound for 30 min, added water to volume after complete dissolving, fluted, and then pipetted 1 ml to 100 ml volumetric flask, added water to volume, it is sample solution. The method of example 9 was used for detection and the result was shown in table 12. TABLE 12 Detection for L-carnitine slimming capsule Aver- 1 2 3 4 5 6 age RSD L-carnitine 20.14 19.77 20.50 19.93 20.51 20.75 20.27 1.87% (mg/100 mg) Example 14 Detection of Free Carnitine in Plasma Pretreatment of test plasma: 100 μl plasma (brought from blood-bank), was pipetted and 400 μl of 10% methanol acetonitrile was added in, shaken, oscillated on a vortex mixer for 5 min, centrifuged at 10000 r·min−1 for 10 min, the supernatant was used as sample solution. Control solution: 35 mg DL-carnitine was weighted precisely and dissolved in 100 mL volumetric flask to volume, then 1 ml solution was pipetted to 100 ml volumetric flask, added water to volume. The method of example 9 was used for detection and the result was shown in table 13. TABLE 13 Detection of free carnitine in plasma Aver- 1 2 3 4 5 6 age RSD L-carnitine 45.12 46.32 45.85 45.77 45.91 46.52 45.92 1.06% (μmol/L) Example 15 Detection of Carnitine Levels in Meat Meat sample preparation: fresh meat was crushed firstly, 2 g crushed sample was weighted and 25 ml of 10% methanol acetonitrile solution was added, homogenated for 5 min, treated with ultrasound for 30 min, centrifuged at 10000 r·min−1 for 10 min, transferred supernatant, 25 ml of 10% methanol acetonitrile solution was added in the residual, treated with ultrasound for 30 min, centrifuged at 10000 r·min−1 for 10 min, supernatant was combined. It is the sample solution. 100 mg DL-carnitine was weighted precisely and dissolved in 100 mL volumetric flask to volume, then 1 ml solution was pipetted to 100 ml volumetric flask, added water to volume. The method of example 9 was used for detection and the result was shown in table 14. TABLE 14 Detection of carnitine leve in Pork, Beef and Lamb Aver- 1 2 3 4 5 age RSD Pork (g/kg) 0.22 0.22 0.23 0.24 0.24 0.23 4.35% Beef (g/kg) 0.64 0.68 0.66 0.65 0.62 0.65 3.44% Lamb (g/kg) 2.01 2.2 2.15 2.12 2.22 2.14 3.87%
A preparation method and its use of derivatization reagent for detecting L-carnitine or D-carnitine are provided. The present reagent is stable. It can be used for detecting L-carnitine or D-carnitine accurately and sensitively. That is to say, the reagent is applied to detecting the amount of synthesized or natural L-carnitine and the amount of mixing D-carnitine. The compound reagent is used for determining the chiral isomers of chemicals, biological reagents, health care reagents, cosmetic, body fluids and various foods, which contain L-carnitine or/and D-carnitine, and optical isomers of other chiral amino acids.
Identify and summarize the most critical technical features from the given patent document.
[ "FIELD OF THE INVENTION This invention relates to preparation and its use of derivatization reagent for detecting L-carnitine or D-carnitine.", "BACKGROUND OF THE INVENTION L-carnitine has a variety of physiological functions, which the basic one is to “transport”", "long-chain fatty acids into mitochondria via mitochondrial membrane where the β oxidation happens.", "L-carnitine is essential to fatty acid metabolism that once the synthesis of carnitine is blocked in body, or carnitine is degraded or excreted excessively, or the function of carnitine transferase decreases or losses, disturbance of lipid metabolism occurs which affects energy supply and leads to many diseases.", "Typical extraction method for natural L-carnitine is extracting from beef which is reported by Cater in 1952.", "However because the absolute content of L-carnitine is very low in meat, and the choline existing in gravy which is very similar in structure makes it is difficult to separate them, the direct extracting method is complicated, with low yield and high price.", "Therefore, it is not easy to get abundant natural L-carnitine.", "Currently, L-carnitine for medicinal use is usually synthesized artificially.", "Usually, separation of racemic compounds is used for L-carnitine synthesis.", "The raw materials are cheap and easy to get, the process is easy to industrialize.", "However, because the defects of traditional chemical resolution, D-isomer can not be removed completely, the synthetic L-carnitine is not absolutely laevorotatory, but contains D-carnitine.", "Natural carnitine is L-carnitine, and only L-carnitine is physiological active is a competitive inhibitior of carnitine acetyl transferase (CAT) and carnitine palmityl transferase (PTC).", "Therefore about 10% patients suffered myasthenia gravis after taking the DL-carnitine (Martindale: the Extra Pharmacopoeia (33th): 1356).", "Therefore taking drug safety into consideration, it's necessary to strictly control the content of the D-carnitine in the chemical synthetic process.", "Currently, the content of D-Carnitine is detected by specific rotation which is lack of accuracy.", "In order to detect accurately the content of D-carnitine in L-carnitine products, and provide much safer and more effective drugs, health products and food, it is necessary to develop a method to detect the content of D-carnitine in L-carnitine products which is more accurate and sensitive.", "SUMMARY OF THE INVENTION One object of this invention is to provide a reagent for detecting the content of L-carnitine (or D-carnitine) and its preparation.", "The preparation method disclosed in the present invention is simple, economical.", "The reagent produced by this method is stable during preservation and is easy to use.", "The second object of this invention is to provide a method to detect the content of L-carnitine (or D-carnitine) in active pharmaceutical ingredients of L-carnitine or D-carnitine, and in various pharmaceutical preparations or biological agents, health care products, cosmetics, body fluids and various food products which contain L-carnitine or/and D-carnitine.", "The detection method disclosed in the present invention has high sensitivity and is convenient and efficient.", "The present invention discloses an optically pure derivatization reagent of formula (I) for detecting the content of L-carnitine (or D-carnitine): wherein, the carbon atom marked with an asterisk is the chiral carbon atom;", "the compounds in the present invention are chiral compounds having pure optical active, the D- or L-compound;", "R represents C1-C6 straight-chain or branched alkyl groups, C6-C10 aryl groups, C2-C6 straight-chain or branched alkenyl or alkynyl groups or C3-C6 cycloalkyl groups;", "and X represents a halogen atom.", "The compound of formula (I) used in the present invention, wherein R represents methyl, ethyl, isopropyl, butyl or benzyl, and X represents Cl or Br.", "Preferably, the present invention discloses (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride as the derivatization reagent for detecting the content of L-carnitine or D-carnitine.", "The derivatization reagents for detecting the content of L-carnitine or D-carnitine disclosed in the present invention, preferably, are crystalline solid of optically pure compound of formula (I), which is more stable, difficulty decomposed, and easy to preserve comparing to its solution.", "The crystalline solid of optically pure compound of formula (I) in the present invention is recrystal with suitable solvent;", "the said solvent is selected from: ether, propyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, acetonitrile, propionitrile, ethyl acetate, n-hexane, dichloromethane, chloroform, or the mixture of any two or more solvents above.", "The solvent for recrystallisation of optically pure compound of formula (I) is preferably acetonitrile.", "The present invention also discloses using the optically pure compound of formula (I) as a derivatization reagent, which the preparation is dissolving the optically pure compound of formula (I) and its crystalline in solvents to form solutions with certain concentration, said solvent is selected from: ether, propyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, acetonitrile, propionitrile, ethyl acetate, n-hexane, dichloromethane, chloroform, or the mixture of any two or more solvents above.", "The concentration of the solution is 0.01˜100 mg/ml.", "Specially preferably, the solvent is acetonitrile and the concentration of the solution is 1-10 mg/ml.", "The crude active ingredient of formula (I) is produced by the steps below: (+) or (−)α-methyl-6-methoxy-2-naphthyl acetic acid is hydrolyzed, and then the phenolichydroxyl group is combined with halohydrocarbon, the product forms crude acylhalide by acylation.", "The present invention also discloses preparation of the crystalline solid of optically pure compound of formula (I) that the crude acylhalide is recrystallised with suitable solvent to form the crystalline solid.", "The said solvent is selected from ether, propyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, acetonitrile, propionitrile, ethyl acetate, n-hexane, dichloromethane, chloroform, or the mixture of any two or more solvents above.", "The solvent for recrystallisation of optically pure compound of formula (I) is preferably acetonitrile, so that the crystalline solid obtained has high optical purity, and can be stably preserved.", "The present invention discloses the crystalline of optically pure compound of formula (I), (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride, which has the characteristic of white and needle crystalline, m.p 92.3˜93.5° C.;", "X-Ray data: diffraction angle (2θ) is 6.579 (d=13.4231, I/I 0 =54.4), 10979 (d=8.0522, I/I 0 =34.1), 13.218 (d=6.6925, I/I 0 =72.2), 13.499 (d=6.5539, I/I 0 =45.8), 18.222 (d=4.8646, I/I 0 =21.2), 18.780 (d=4.7211, I/I 0 =100.0), 19.901 (d=4.4577, I/I 0 =21.7), 21.619 (d=4.1072, I/I 0 =26.2), 22.100 (d=4.0188, I/I 0 =75.3), 27.139 (d=3.2830, I/I 0 =19.0), 47.681 (d=1.9057, I/I 0 =15.0);", "IR: 3414.5 cm −1 , 2983.2 cm −1 , 1786.2 cm −1 , 1605.0 cm −1 , 1390.6 cm −1 , 1270.4 cm −1 , 1183.1 cm −1 , 823.8 cm −1 , 701.6 cm −1 , 7412 cm −1 ;", "1 HNMR (CD3COCD3, 500 MHz): 1.66 (m, 3H), 3.78 (s, 3H), 4.46 (m, 1H), 7.19 (m, 1H), 7.29 (m, 1H), 7.43 (m, 1H), 7.82 (m, 1H), 7.83 (s, 1H), 7.85 (s, 1H);", "elemental analysis: C %: 67.76 (theoretical value is 67.61), H %: 5.25 (5.27).", "MS: the molecular weight is 248, 250, it is the isotopic peak of chlorine, m/z 185 is the base peak with the abundances of 100%, from which can be supposed as the fragment ion of formula The present invention discloses a method for detecting the content of L-carnitine or D-carnitine in a sample;", "the detection includes the following steps: (1) Prepare the test sample solution containing proper amount of L-carnitine (or D-carnitine) and the control solution containing DL-carnitine.", "(2) Mix proper amount of derivative reagent of the present invention and the test sample solution containing L-carnitine (or D-carnitine), and let them react to afford L-carnitine (or D-carnitine) derivatives.", "(3) Apply HPLC to detect and calculate the content of L-carnitine (or D-carnitine) in the sample.", "The present invention discloses a method for detecting the content of L-carnitine or D-carnitine in a sample, wherein the detection includes the following steps: (1) Prepare the derivatization reagent solution: D-type or L-type optical pure compound of formula (I) of any of claims 1 to 5 is dissolved in solvent to form a 0.01˜100 mg/ml solution under the dark conditions, wherein the compound of formula (I) is preferably (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride, and the solvent is preferably acetonitrile;", "the concentration of solution is preferably from 1 to 10 mg/ml.", "(2) Prepare of the test solution of L-carnitine or D-carnitine, and control solution of DL-carnitine;", "(3) Derived reagent of step (1) is mixed and reacted with test solution and control solution of step (2) respectively in a airtight vessel, in the present of solvent at 20° C.˜95° C. in a water bath for 20 min to 180 min;", "(4) HPLC is applied to separate and detect the reacted test solution and control solution, the content of L-carnitine (or D-carnitine) in test solution is calculated by external standard method.", "Detailed detection also includes: (1) Chromatographic conditions: The octadecyl silane bonded silica is taken as a filler, and triethylamine buffer (phosphate 8 ml, triethylamine, 15 ml, water 1500 ml)-tetrahydrofuran is taken as mobile phase for gradient elution.", "Excitation wavelength is from 230 nm to 260 nm and emission wavelength is from 340 nm to 380 nm.", "(2) Preparation of test solution: test sample is precisely weighed and dissolved in water to form 0.1 μg/ml˜3.0 μg/ml solution which is the test solution.", "(3) Preparation of control solution: DL-carnitine is precisely weighed and desolved in water to form 0.2 μg/ml˜6.0 μg/ml solution which is the control solution.", "(4) Derivatization reaction: 30 μl of control solution and test solution is put in 5 ml volumetric flask respectively, for, each one, 0.01 mol/L˜0.5 mol/L of carbonate buffer solution is added in, proper amount of pyridine acetonitrile solution (per 1 ml acetonitrile contains 1 μl˜50 μl of pyridine) is mixed with derivatization reagent solution of the present invention, sealed and reacted at 20° C.˜95° C. in warm water bath, which is diluted with acetic acid buffer to the scale, shaken and tilted right after removing from the bath.", "(5) Content detection: the same amount of reacted test sample and the control solution is injected in HPLC respectively, chromatograms is recorded and the content of L-carnitine (or D-carnitine) in test solution is calculated by external standard method.", "L-carnitine (or D-carnitine) content detection of the present invention, wherein the above mentioned chromatographic conditions of step (1) comprise a mobile phase which is a mix of the triethylamine buffer (phosphate 8 ml, triethylamine, 15 ml, water 1500 ml) and tetrahydrofuran.", "The pH value of triethylamine buffer solution is 2.0%˜9.0.", "The gradient of the two components is 0-10 min, when the concentration of triethylamine buffer is 70%˜90%, and that of THF is 30%˜10%;", "it is 10%˜11 min, when the concentration of triethylamine buffer is from 70% to 30%˜90% to 30%, and that of THF is from 30% to 70%˜10% to 70%;", "it is 11˜18 min, when the concentration of triethylamine buffer is 30%, and that of tetrahydrofuran is 70%;", "it is 18˜19 min, when the concentration of triethylamine buffer is from 30% to 70%˜30% to 90%, and that of THF is from 70% to 30%˜70% to 10%;", "it is 19˜25 min, when the concentration of triethylamine buffer is 70%˜90%, and that of THF is 30%˜10%.", "L-carnitine (or D-carnitine) content detection of the present invention, wherein control solution of step (3) is prepared in detail that DL-carnitine 2 mg˜60 mg is weighted precisely and dissolved with water in a 100 mL of volumetric flask, volume, 10 ml of which is precisely pipetted into a 100 ml of volumetric flask, added water to volume.", "It is the control solution.", "When the concentration of L-carnitine (or D-carnitine) is 0.1 μg/ml˜3.0 μg/ml, there is a good linear relationship, which the linear correlation coefficient r equals to 0.9991 and the recovery is 100.6%.", "L-carnitine (or D-carnitine) content detection of the present invention, wherein derivatization reagent concentration of step (4) is 0.01˜100 mg/ml, preferably is 1-10 mg/ml, most preferably is 5 mg/ml.", "L-carnitine (or D-carnitine) content detection of the present invention, wherein carbonate buffer solution of step (4) prepared in detail that 4.2 g sodium bicarbonate is dissolved in 900 ml water, and pH value is adjusted with 5 mol/L of hydrogen sodium to 7.0˜12.0, added water to 1000 mL.", "L-carnitine (or D-carnitine) content detection of the present invention, wherein the quantity added in carbonate buffer solution of step (4) is 5 μl to 500 μl.", "L-carnitine (or D-carnitine) content detection of the present invention, wherein the reaction temperature of step (4) is 20° C.-95° C., and reaction time is 20 min˜180 min.", "L-carnitine (or D-carnitine) content detection of the present invention, wherein the acetate buffer solution of step (4) is prepared in detail that 3.0 mL glacial acetic acid is dissolved with 900 mL water, and pH value is adjusted with 5 mol/L of sodium hydroxide solution to 2.0˜7.0, and added water to 1000 mL.", "The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of L-carnitine and/or D-carnitine in various pharmaceutical preparations or biological agents, health care products, cosmetics, body fluids and various food products which contain L-carnitine or/and D-carnitine, such as: L-carnitine API, injection, oral liquid, tablets, slimming capsules, drinks and etc.", "The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of carnitine in the tissue and plasma of various mammals, including human.", "The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of carnitine in various edible plant and animal food.", "Such as: pig, cattle, sheep, chicken, shrimp, fish, eggs, vegetables, fruits and etc.", "The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of carnitine in various animal feed.", "The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the content of carnitine in various plant nutrients.", "The present invention discloses the derivatization reagent of the present invention and detection method, which is applied to detect the optical purity other chiral amino acids.", "The description of the code used in the invention: D-: D-isomer L-: L-isomer IR: infrared absorption spectroscopy HNMR: H Nuclear Magnetic Resonance MS: mass spectrometry HPLC: high performance liquid chromatography (+) MNPC: (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride (+) ENPC: (+)α-methyl-6-ethoxy-2-naphthyl acetyl chloride (+) PNPC: (+)α-methyl-6-isopropoxy-2-naphthyl acetyl chloride (+) BUNPC: (+)α-methyl-6-butoxy-2-naphthyl acetyl chloride (+) BNPC: (+)α-methyl-6-benzoxy-2-naphthyl acetyl chloride BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is the excitation spectrum of detecting the content of L-carnitine (or D-carnitine);", "FIG. 2 is the emission spectrum of detecting the content of L-carnitine (or D-carnitine);", "FIG. 3 is the HPLC of detecting the content of L-carnitine [L-carnitine (tR=5.139 min)];", "FIG. 4 is the HPLC of detecting the content of L-carnitine[D-carnitine (tR=4.389 min), L-carnitine (tR=5.136 min)].", "DETAILED DESCRIPTION OF THE INVENTION The following implementations are used to explain the present invention, but not limit the scope of this invention.", "Example 1 Preparation of (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride ((+) MNPC) 4.6 g (+)α-methyl-6-methoxy-2-naphthyl acetic acid and 50 ml THF was added in a 100 ml of single neck bottle, cooled with ice water, stirred with magnetic force, added 2 ml SOCl2, added proper amount of pyridine, reacted for 6 h, dried by rotary, added 20 ml acetonitrile, cooled to give faint yellow solid, recrystallised with 15 ml acetonitrile to give white needle crystal.", "Dried under vacuum to give 2.87 g of product, yield 57%, m.p 92.3-93.5° C. IR: 3414.5 cm −1 , 2983.2 cm −1 , 1786.2 cm −1 , 1605.0 cm −1 , 1390.6 cm −1 , 1270.4 cm −1 , 1183.1 cm −1 , 832.8 cm −1 , 701.6 cm −1 , 472.2 cm −1 .", "1HNMR ((CD3COCD3, 500 MHz): 1.66 (m, 3H), 3.78 (s, 3H), 4.46 (m, 1H), 7.19 (m, 1H), 7.29 (m, 1H), 7.43 (m, 1H), 7.82 (m, 1H), 7.83 (s, 1H), 7.85 (s, 1H);", "X-Ray data: diffraction angle (2θ) is 6.579 (d=13.4231, I/I 0 =54.4), 10979 (d=8.0522, I/I 0 =34.1), 13.218 (d=6.6925, I/I 0 =72.2), 13.499 (d=6.5539, I/I 0 =45.8), 18.222 (d=4.8646, I/I 0 =21.2), 18.780 (d=4.7211, I/I 0 =100.0), 19.901 (d=4.4577, I/I 0 =21.7), 21.619 (d=4.1072, I/I 0 =26.2), 22.100 (d=4.0188, I/I 0 =75.3), 27.139 (d=3.2830, I/I 0 =19.0), 47.681 (d=1.9057, I/I 0 =15.0);", "MS: MW 248, 250, it is the isotopic peak of chlorine, m/z 185 is the base peak with the abundances of 100%, from which can be supposed as the fragment ion of formula Elemental analysis: C %: 67.76 (theoretical value is 67.61), H %: 5.25 (5.27) Example 2 Preparation of (+)α-methyl-6-ethoxy-2-naphthyl acetyl chloride ((+) ENPC) Step 1 50 g (+)α-methyl-6-ethoxy-2-naphthyl acetic acid was dissolved in 205 ml glacial acetic acid, heated under reflux, added 20 ml of 36% HCl in each 30 min, reacted for 6 h. and poured into 600 g ice water, filtered, recrystallised with ethanol-water, dried to give colorless crystal (9.87 g), yield 90.5%, m.p 189.4˜191.3° C.;", "IR: 3411.1 cm −1 , 1701.4 cm −1 , 1632.5 cm −1 , 1606.2 cm −1 , 1509.1 cm −1 , 1384.4 cm −1 , 1189.0 cm −1 , 1147.3 cm −1 , 865.9 cm −1 , 477.8 cm −1 .", "1HNMR ((CD3COCD3, 500 MHz): δ1.53 (m, 3H), 3.98 (s, 3H), 7.15 (m, 1H), 7.20 (m, 1H), 7.42 (m, 1H), 7.67 (m, 1H), 7.73 (s, 1H), 7.76 (m, 1H), 8.55 (s, 1H);", "Step 2 The product of step 1 (41.0 g) and KOH (32.0 g) was dissolved in 200 ml of methanol, added 35.5 ml bromoethane, heated under reflux for 2 h, added 200 ml of 5% NaOH after cooled, and reacted for 3˜4 h, added 600 ml ice water after reaction, stirred, rested and filtered, washed with water, recrystallised with 500 ml ethanol and dried at 80° C. to give product (37.2 g), yield 80.3%, m.p 151.8˜155.6;", "IR: 3453.5 cm −1 , 1729.6 cm −1 , 1609.5 cm −1 , 1604.5 cm −1 , 1393.7 cm −1 , 1181.9 cm −1 , 1158.4 cm −1 , 862.4 cm −1 , 481.8 cm −1 .", "1HNMR ((CD3COCD3, 500 MHz): σ1.43 (m, 3H), 1.53 (m, 3H), 3.90 (m, 1H), 4.16 (m, 2H), 7.15 (m, 1H), 7.25 (m, 1H), 7.46 (m, 1H), 7.75 (s, 1H), 7.76 (s, 1H), 7.79 (s, 1H).", "Step 3 Formation of acyl chloride from the product of step 2 according to example 1, m.p 91.7˜92.9° C. IR: 3416.7 cm −1 , 2982.1 cm −1 , 1785.9 cm −1 , 1605.2 cm −1 , 1309.5 cm −1 , 1269.1 cm −1 , 1182.6 cm −1 , 832.8 cm −1 , 701.8 cm −1 , 472.6 cm −1 .", "1HNMR ((CD3COCD3, 500 MHz): σ1.43 (m, 3H), 1.66 (m, 3H), 4.18 (m, 2H), 4.46 (m, 1H), 7.19 (m, 1H), 7.29 (m, 1H), 7.43 (m, 1H), 7.82 (m, 1H), 7.83 (s, 1H), 7.85 (s, 1H) Example 3 Preparation of (+)α-methyl-6-isopropoxy-2-naphthyl acetyl chloride ((+) PNPC) 2-bromopropane was used in step 2 according to the method of example 1 to give (+) PNPC, m.p 77.8˜79.4° C.;", "IR: 3416.3 cm −1 , 1784.5 cm −1 , 1604.8 cm −1 , 1390.2 cm −1 , 1270.3 cm −1 , 1182.5 cm −1 , 854.6 cm −1 , 699.2 cm −1 , 469.5 cm −1 .", "1HNMR ((CD3COCD3, 500 MHz): δ 1.06 (m, 3H), 1.65 (m, 3H), 1.83 (m, 2H), 4.07 (m, 2H), 4.45 (m, 1H), 7.19 (m, 1H), 7.29 (m, 1H), 7.42 (m, 1H), 7.81 (m, 1H), 7.82 (s, 1H), 7.84 (m, 1H).", "Example 4 Preparation of (+)α-methyl-6-butoxy-2-naphthyl acetyl chloride ((+)BUNPC) Bromobutane was used in step 2 according to the method of example 1 to give (+) BUNPC, m.p 56.3˜57.3° C.;", "IR: 3415.7 cm −1 , 1785.3 cm −1 , 1605.2 cm −1 , 1468.3 cm −1 , 1392.3 cm −1 , 1268.9 cm −1 , 1178.3 cm −1 , 921.8 cm −1 , 819.9 cm −1 , 727.45 cm −1 , 747.6 cm −1 .", "1HNMR ((CD3COCD3, 500 MHz): δ1.00 (m, 3H), 1.55 (m, 2H), 1.67 (m, 3H), 1.82 (m, 2H), 4.14 (m, 2H), 4.48 (m, 2H), 7.19 (m, 1H), 7.31 (m, 1H), 7.42 (m, 1H), 7.82 (m, 1H), 7.83 (s, 1H), 7.85 (m, 1H).", "Example 5 Preparation of (+)α-methyl-6-benzoxy-2-naphthyl acetyl chloride ((+) BNPC) Benzyl bromide was used in step 2 according to the method of example 1 to give (+) BUNPC, m.p 77.2˜79.1° C. 1HNMR ((CD3COCD3, 500 MHz): δ1.6 (d, 3H), 3.81 (m, 1H), 4.14 (m, 2H), 4.48 (m, H), 5.26 (s, 2H), 7.19 (m, 1H), 7.22 (m, 1H), 7.38 (m, 3H), 7.42 (m, 1H), 7.47 (m, 2H), 7.83 (m, 1H), 7.87 (m, 1H), 7.90 (m, 1H).", "Example 6 Derivatization reaction and chromatographic conditions 1.", "Chromatographic Conditions and Systematic Adaptability Test: Agilent 1100 HPLC;", "fluorescence detector;", "column: C18-ODS column (4.6×150 mm, 5 μm);", "the total flow rate: 1 ml/min;", "mobile phase: the triethylamine buffer (phosphate 8 ml, triethylene amine 15 ml, water 1500 ml, pH adjusted to 5.4)-tetrahydrofuran mixture, the time gradient of the following Table 1: TABLE 1 HPLC time gradient table Time Triethylamine THF (min ) buffer ( % ) (%) 0 75 25 10 75 25 11 30 70 18 30 70 19 75 25 25 75 25 Number of theoretical plates was greater than 5000, and the resolution of the peak both of L-carnitine and D-carnitine was more than 1.5.", "Detection Wavelength The spectral scan was carried out after derivatization reaction ( FIG. 1 , 2 ).", "Ultimately the excitation wavelength of 234 nm and emission wavelength of 360 nm was chosen.", "Preparation of Control Solution 20 mg DL-carnitine was precisely wighted and dissolved with water in 100 mL volumetric flask to volume, and then 10 ml solution was precisely pipetted in 100 ml volumetric flask, added water to volume.", "It is the control solution.", "Derivatization Reaction: 30 μl of control solution and test solution is put in 5 ml volumetric flask respectively, for, each one, 100 μl of 0.05 mol/L carbonate buffer solution (4.2 g sodium bicarbonate was dissolved in 900 ml water, pH was adjusted to 8.4 with 5 mol/L NaOH), 100 μl of pyridine acetonitrile solution (per 1 ml acetonitrile contains 25 μl of pyridine) and 200 μl of derivatization reagent solution (0.5% (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride) is mixed, sealed and reacted at 40° C. in worm water bath for 60 min, which is diluted with acetic acid buffer (3 ml glacial acetic acid was dissolved in 900 ml water, pH was adjusted with 5 mol/L NaOH to 7.0, added water to 1000 mL) to the scale, shaken and felted right after remove from the bath.", "Detection: 10 μl of reacted test sample and the control solution is injected in HPLC respectively, chromatograms is recorded and the content of L-carnitine (or D-carnitine) in test solution is calculated by external standard method When sample concentration of L-carnitine (or D-carnitine) is 0.33 μg/ml˜1.64 μg/ml, there was a good linear relationship, and linear correlation coefficient r equaled to 0.9991, and recovery was 100.6%.", "Example 7 Crystallization of the Compound of Formula (I) and the Stability of the Solution Containing the Compound An accurate content of derivatization reagent is the ensurance of accurate results.", "However, the compounds of formula (I) are acyl chloride which is active chemically and easily decomposed in water, it is necessary to find a proper preservation and use conditions which include choosing suitable solvent to ensure the stability of the compounds of formula (I) and decreases the detecting error The solvent is selected from ether, propyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, acetonitrile, propionitrile, ethyl acetate, and etc, the crystal, is dissolved in solvent to form solution, the stability of crystal and solution is detected together.", "The stability tests of 5 mg/ml of (+)α-methyl-6-methoxy-2-naphthyl chloride ((+) MNPC) solutions (dissolved in acetonitrile, acetone, ethyl acetate respectively) and relative solid crystal were carried on the experimental data was shown in table 2, table 3, table 4, and table 5.", "TABLE 2 Investigation of (+)MNPC solid's stability Refrigerated storage time (months) Fresh 0.5 1 2 3 6 12 (+) MNPC content (%) 99.55 99.50 99.53 99.39 99.30 99.09 98.52 (−) MNPC content (%) 0.12 0.13 0.12 0.13 0.14 0.15 0.15 Other impurities (%) 0.33 0.37 0.35 0.48 0.56 0.76 1.33 Note: storage condition, dispensed in brown glass, sealed and freeze-preserved (−15° C.) - TABLE 3 Investigation of (+)MNPC acetonitrile solution's stability Refrigerated storage time (day) Fresh 3 10 20 30 50 80 (+) MNPC content (%) 99.55 99.55 99.51 99.09 99.55 99.15 97.48 (−) MNPC content (%) 0.12 0.13 0.16 0.19 0.16 0.23 0.31 Other impurities (%) 0.33 0.32 0.33 0.72 0.29 0.62 2.21 Note: storage condition, dispensed in brown glass, sealed and freeze-preserved (−15° C.) TABLE 4 Investigation of (+)MNPC acetone solution's stability Refrigerated storage time (day) Fresh 3 10 20 30 50 80 (+) MNPC content (%) 99.55 99.04 98.64 97.33 96.21 94.83 90.51 (−) MNPC content (%) 0.12 0.15 0.17 0.21 0.24 0.42 0.73 Other impurities (%) 0.33 0.81 1.19 2.46 3.55 4.75 8.76 Note: storage condition, dispensed in brown glass, sealed and freeze-preserved (−15° C.) TABLE 5 Investigation of (+) MNPC ethyl acetate solution's stability Refrigerated storage time (day) Fresh 3 10 20 30 50 80 (+) MNPC content (%) 99.55 95.88 90.90 84.13 67.96 50.22 16.52 (−) MNPC content (%) 0.12 0.98 1.77 3.11 3.85 4.01 4.82 Other impurities (%) 0.33 3.14 7.33 12.76 28.19 45.77 78.66 Note: storage condition, dispensed in brown glass, sealed and freeze-preserved (−15° C.) It is shown in from table 2 to table 5 that solid crystal of MNPC is more stable than any solution in all samples, and in all the solutions the MNPC acetonitrile solution had the best stability which the content decreased obviously since the 60th day while others were even worse.", "Therefore, MNPC solid crystal has the best stability, as a derivatization reagent, it is suitable for long-term preservation and transportation;", "in all the solutions, the MNPC acetonitrile solution has the best stability, acetonitrile is a suitable solvent for preparing the derivatization reagent and conducting derivatives reaction.", "Example 8 Precise detection of the content of D-Carnitine in synthetic L-carnitine 100 mg L-carnitine was precisely weighted and dissolved with water in 100 ml of volumetric flask to volume, 10 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the sample solution;", "20 mg DL-carnitine was weighted and dissolved with water in 100 ml volumetric flask to volume, and 1 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the control solution.", "30 μl of control solution and sample solution was pipetted precisely respectively in 5 ml volumetric flask, for each one, 100 μl of 0.05 mol/L carbonate buffer solution (4.2 g sodium bicarbonate was dissolved in 900 ml water, pH was adjusted to 8.4 with 5 mol/L NaOH), 100 μl of pyridine acetonitrile solution (per 1 ml acetonitrile contains 25 μl of pyridine) and 200 μl of derivatization reagent solution (0.5% (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride) was mixed, sealed and reacted at 40° C. in worm water bath for 60 min, which was diluted with acetic acid buffer (3 ml glacial acetic acid was dissolved in 900 ml water, pH was adjusted with 5 mol/L NaOH to 7.0, added water to 1000 mL) to the scale, shaken and lilted right after remove from the bath.", "10 μl of control solution and sample solution was pipetted and injected respectively in HPLC, chromatograph was recorded and the content of D-carnintine was calculated by external standard method The result was shown in table 6.", "TABLE 6 Detection of D-carnitine in synthetic L-carnitine Aver- 1 2 3 4 5 6 age RSD D-carnitine 0.99 0.97 1.00 0.98 1.00 0.98 0.99 1.22% (%) Example 9 Detection of the Content of L-Carnitine 10 mg L-carnitine was precisely weighted and dissolved with water in 100 ml of volumetric flask to volume, 1 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the sample solution;", "20 mg DL-carnitine was weighted and dissolved with water in 100 ml volumetric flask to volume, and 1 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the control solution.", "30 μl of control solution and sample solution was pipetted precisely respectively in 5 ml volumetric flask, for each one, 100 μl of 0.05 mol/L carbonate buffer solution (pH=8.4), 100 μl of pyridine acetonitrile solution and 100 μl of 0.5% derivatization reagent acetonitrile solution was mixed, sealed and reacted at 40° C. in worm water bath for 60 min, which was diluted with 0.05 mol/L acetic acid buffer (pH 7.0) to the scale, shaken and tilted right after remove from the bath.", "10 μl of control solution and sample solution was pipetted and injected respectively in HPLC, chromatograph was recorded and the content of D-carnintine was calculated by external standard method The result was shown in table 8.", "TABLE 8 Detection of L-carnitine Aver- 1 2 3 4 5 6 age RSD L-carnitine 98.53 98.88 98.82 98.67 99.13 98.72 98.79 0.21% (%) Example 10 Detection of L-Carnitine and D-Carnitine in L-Carnitine API Synchronously 100 mg food containing L-carnitine was weight precisely and dissolved in 100 ml of volumetric flask to volume, 1 ml solution was pipetted in 100 ml volumetric flask, added water to volume, which is the sample solution;", "20 mg DL-carnitine was weighted and dissolved with water in 100 ml volumetric flask to volume, which was the control 1;", "and 1 ml “control 1”", "solution was pipetted in 100 ml volumetric flask, added water to volume, which is the control 2.", "30 μl of “control 1”, “control 2”", "and sample solution was pipetted precisely respectively in 5 ml volumetric flask, for each one, 100 μl of 0.05 mol/L carbonate buffer solution (4.2 g sodium bicarbonate was dissolved in 900 ml water, pH was adjusted to 8.4 with 5 mol/L NaOH), 100 μl of pyridine acetonitrile solution (per 1 ml acetonitrile contains 25 μl of pyridine) and 100 μl of derivatization reagent solution (0.5% (+)α-methyl-6-methoxy-2-naphthyl acetyl chloride) was mixed, sealed and reacted at 40° C. in worm water bath for 60 min, which was diluted with acetic acid buffer (3 ml glacial acetic acid was dissolved in 900 ml water, pH was adjusted with 5 mol/L NaOH to 7.0, added water to 1000 mL) to the scale, shaken and filted right after remove from the bath.", "10 μl of control solution and sample solution was pipetted and injected respectively in HPLC, chromatograph was recorded and the content of D-carnintine was calculated by external standard method.", "The result was shown in table 9.", "TABLE 9 Detection for L-carnitine API Aver- 1 2 3 4 5 6 age RSD L-carnitine 98.01 97.75 98.57 97.83 98.19 97.64 98.00 0.35% (%) D-carnitine 0.58 0.61 0.59 0.59 0.61 0.60 0.60 2.03% (%) Example 11 Detection of the Content of L-Carnitine in Injection L-carnitine injection (5 ml: 1 g) 1 mL was pipetted precisely in 100 mL volumetric flask, added water to volume, 1 ml of the solution was pipetted precisely in 100 ml volumetric flask, added water to volume, and 5 ml of the solution was pipetted precisely in 100 ml, added water to volume.", "It is the sample solution.", "The method of example 9 was used for detection and the result was shown in table 10.", "TABLE 10 Detection of L-carnitine injection (labelled amount) Aver- 1 2 3 4 5 6 age RSD L-carnitine 100.55 99.81 100.19 99.72 100.3 100.39 100.16 0.33% (%) Example 12 Detection of the Content of L-Carnitine in Oral Solution L-carnitine oral solution (10 ml: 1 g) 1 mL was pipetted precisely in 100 ml volumetric flask, added water to volume, 1 ml of the solution was pipetted precisely in 100 ml volumetric flask, added water to volume, and 10 ml of the solution was pipetted precisely in 100 ml, added water to volume.", "It is the sample solution.", "The method of example 9 was used for detection and the result was shown in table 11.", "TABLE 11 Detection for L-carnitine oral solution (labeled amount) Aver- 1 2 3 4 5 6 age RSD L-carnitine 97.88 98.05 97.55 98.23 97.77 97.71 97.86 0.25% (%) Example 13 Detection of the Content of L-Carnitine in Slimming Capsule 20 L-carnitine slimming capsules were weighted precisely, the contents of capsules were poured out (without losing capsule shell which was weighted followed by cleaning with small brush);", "the contents of capsules were mixed, porphyrized, weighted properly (equaled to 10 mg L-carnitine) and put in 100 ml volumetric flask, added water and treated with ultrasound for 30 min, added water to volume after complete dissolving, fluted, and then pipetted 1 ml to 100 ml volumetric flask, added water to volume, it is sample solution.", "The method of example 9 was used for detection and the result was shown in table 12.", "TABLE 12 Detection for L-carnitine slimming capsule Aver- 1 2 3 4 5 6 age RSD L-carnitine 20.14 19.77 20.50 19.93 20.51 20.75 20.27 1.87% (mg/100 mg) Example 14 Detection of Free Carnitine in Plasma Pretreatment of test plasma: 100 μl plasma (brought from blood-bank), was pipetted and 400 μl of 10% methanol acetonitrile was added in, shaken, oscillated on a vortex mixer for 5 min, centrifuged at 10000 r·min−1 for 10 min, the supernatant was used as sample solution.", "Control solution: 35 mg DL-carnitine was weighted precisely and dissolved in 100 mL volumetric flask to volume, then 1 ml solution was pipetted to 100 ml volumetric flask, added water to volume.", "The method of example 9 was used for detection and the result was shown in table 13.", "TABLE 13 Detection of free carnitine in plasma Aver- 1 2 3 4 5 6 age RSD L-carnitine 45.12 46.32 45.85 45.77 45.91 46.52 45.92 1.06% (μmol/L) Example 15 Detection of Carnitine Levels in Meat Meat sample preparation: fresh meat was crushed firstly, 2 g crushed sample was weighted and 25 ml of 10% methanol acetonitrile solution was added, homogenated for 5 min, treated with ultrasound for 30 min, centrifuged at 10000 r·min−1 for 10 min, transferred supernatant, 25 ml of 10% methanol acetonitrile solution was added in the residual, treated with ultrasound for 30 min, centrifuged at 10000 r·min−1 for 10 min, supernatant was combined.", "It is the sample solution.", "100 mg DL-carnitine was weighted precisely and dissolved in 100 mL volumetric flask to volume, then 1 ml solution was pipetted to 100 ml volumetric flask, added water to volume.", "The method of example 9 was used for detection and the result was shown in table 14.", "TABLE 14 Detection of carnitine leve in Pork, Beef and Lamb Aver- 1 2 3 4 5 age RSD Pork (g/kg) 0.22 0.22 0.23 0.24 0.24 0.23 4.35% Beef (g/kg) 0.64 0.68 0.66 0.65 0.62 0.65 3.44% Lamb (g/kg) 2.01 2.2 2.15 2.12 2.22 2.14 3.87%" ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention concerns a monochromator for an X-ray device of the type having an X-ray source with a crystal for spectral restriction of the X-ray produced by the X-ray source. The invention also concerns an X-ray device that incorporates such a monochromator. 2. Description of the Prior Art X-rays are used in medical and technical diagnostics to obtain images of objects to be examined. The quality of images thus produced depends on the radiation dose and on the energy spectrum of the X-rays. In order to achieve a certain minimum image quality, a certain minimum radiation dose is required, and the minimum radiation dose itself depends on the spectral energy distribution in the X-rays. In addition, depending on the concrete body or object to be examined, there always exists an optimum level of X-radiation energy, i.e., the wavelength of the X-radiation at which a maximum contrast resolution with a simultaneous minimized radiation dose can be achieved. Thus, in order to achieve the requisite minimum image quality with a minimized radiation dose, X-radiation of a suitable spectrum must be used. The spectral energy distribution of X-rays, however, can be influenced at the X-ray source only to a limited extent. For example, the energy spectrum of a conventional X-ray tube always contains wavelength components outside the wavelength that is optimal for the radiation dose and the contrast resolution. The energy spectrum of an X-ray tube is influenced by the choice of anode material and by the type of X-ray absorption filters used. Furthermore, the aforementioned energy spectrum also strongly depends on the X-ray voltage, i.e., the energy with which electrons inside the X-ray tube are accelerated from the cathode to the anode. The X-ray voltage determines the upper limit of the energy spectrum. Changes in the X-ray voltage affect not only the energy spectrum, but also the radiation dose, because with decreasing X-ray voltage, the tube current, i.e., the electron flow inside the X-ray tube, decreases. Thus, in order to compensate for the reduction of the radiation dose with a decrease in X-ray voltage, the X-ray tube current must be increased. The increase of the X-ray tube current, however, is restricted by the so-called blooming effect, by which—due to a lower X-ray voltage and high X-ray currents—the X-ray focal spot on the anode of the X-ray tube enlarges. The blooming effect negatively affects the properties of the X-rays that are produced. Currently, depending on the particular application, a suitable energy spectrum is achieved by an appropriate combination of the anode material, the X-ray absorption filters, and the X-ray voltage. Each energy spectrum thus is necessarily a compromise among the various parameters. European Application 0 924 967 discloses an X-ray device with a monochromator designed on the basis of a so-called mosaic crystal. The mosaic crystal is arranged in the path of radiation beam in such a manner that the X-rays of the X-ray tube are reflected by it. On the basis of Bragg relation for the diffraction of X-rays, for a certain reflection direction spectrally restricted, i.e., quasi-monochromatized, X-rays are obtained. In order to obtain X-rays of various wavelengths, the aforementioned European application proposes to implement multiple mosaic crystals to provide various Bragg angles. The arrangement of multiple mosaic crystals and their associated diaphragms requires a number of components and is therefore costly. Moreover, this arrangement has the inherent drawback that different propagation paths are pre-determined for the X-rays, which have to be individually aimed at the particular object to be examined. SUMMARY OF THE INVENTION An object of the present invention is to provide a monochromator for an X-ray device that makes it possible to variably spectrally restrict X-rays produced by an X-ray device using a reflection crystal, with such a monochromator being inexpensive to design and easy to operate. The above object is achieved in accordance with the present invention by a monochromator for an X-ray device that comprises an X-ray source with a crystal for spectral restriction of the X-ray produced by the X-ray source, wherein, according to the invention, the crystal can be adjusted by a positioning device so that the energy spectrum of the spectrally restricted X-radiation can be changed. The ability to adjust the crystal provides the possibility of adjusting the energy spectrum of the spectrally restricted X-radiation to comply with the requirements for the image to be acquired without having to set the X-ray voltage and X-ray tube current to non-optimal values. For example, using this design the blooming effect that occurs at low X-ray voltages and high X-ray currents can be avoided, or the X-ray tube can always be operated with an X-ray voltage suitable for the particular requisite level of efficiency. At the same time, the adjustability of the crystal allows for a variable adjustment of the energy spectrum to various requirements without the need for changes in the X-ray source (for example, in the anode material). Consistent with conventionally-used terminology, the subject matter described herein is referred to as a “monochromator” even though it does not limit the X-ray radiation to a monochromatic (single energy) beam, but instead spectrally restricts the X-radiation. In an embodiment of the invention, the crystal is adjustable so that the angle between the X-rays (produced by the X-ray source) and the crystal can be changed. According to the Bragg relation, the energy spectrum of the spectrally restricted X-radiation changes dependent on the change of the diffraction angle. Therefore, the ability to change the angle provides a simple and inexpensive means of producing X-radiation with variable energy spectra. Greater changes in the angle, which can be achieved, for example, by tilting the crystal, change the entire X-ray path. However, such changes can be simply compensated for, e.g., by a simultaneous tilting of the X-ray source. The tilting of the crystal performed together with a coordinated tilting of the X-ray source allows for a simple continuous variation of the energy spectrum of X-radiation with an unchanged X-ray path. In another embodiment of the invention, the crystal can be adjusted so that it can be fully removed from and returned into the X-ray path produced by the X-ray source. If the crystal is removed from the X-ray path, Bragg diffraction of the X-ray is prevented, and the original energy spectrum of the X-ray source is reconstituted. Thus, the option of removing and then returning the crystal to the X-ray path provides a simple way of producing either spectrally restricted X-rays or X-rays without any spectral restriction. If, during the removal of the crystal, certain adjustments have to be made to reflect the change in the entire X-ray path, for example, by tilting the X-ray source, this is easy to do. In another embodiment of the invention, the crystal can be automatically adjusted so that we reach a maximum value of the energy spectrum of the spectrally restricted X-radiation is reached that is between 0.34- and 0.8-multiples of the maximum value of the original (unrestricted) energy spectrum of the X-ray source. The original energy, which is greater than in the spectrally restricted X-radiation, is produced by an increased X-ray voltage, which means the blooming effect is reduced. At the same time, by maintaining a minimal factor of about 0.34, the influence of higher-order reflection in the energy spectrum of the spectrally restricted X-radiation is minimized. Higher-order reflection occurs at double, triple, quadruple, etc. the minimum value of the original X-radiation. The indicated range rules out the possibility that reflections from the 3rd order and beyond will be contained in the spectrally restricted X-radiation. DESCRIPTION OF THE DRAWINGS FIG. 1 shows an X-ray device with a monochromator in accordance with this invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS The figure illustrates an X-ray device 3 with a monochromator 1 in accordance with the invention. The monochromator 1 is an accessory device that is connected to the X-ray source 5 as a module; however, the device can also be fully integrated with the X-ray sources. Other components of the X-ray tube, such as a diaphragm, are not essential to the explanation of the invention and therefore are not illustrated. The X-ray device 3 produces spectrally restricted X-radiation 11 in order to generate an image of a patient 29 lying on a patient positioning table 27 . Depending on the type of the required X-ray image, the X-ray path of X-radiation 11 can assume various orientations by moving and turning the X-ray source 5 mounted on the ceiling stand. This also allows examination of, for example, a standing patient, with the monochromator 1 always being used in the same manner. A voltage generator 19 , which is connected to the X-ray source 5 by an electrical line 23 , generates the X-ray voltage and the X-ray tube current to operate the X-ray source 5 . The X-ray generator 19 is controlled by a control device 17 , which is connected to the X-ray generator 19 by a control line 21 . The control device 17 allows entry of all the parameters of the X-ray image that is to be produced. The basic component of the monochromator 1 is a crystal 7 , which reflects X-rays propagating in an X-ray path 9 . The reflection at the crystal spectrally restricted X-radiation 11 , the energy spectrum of which depends on the angle of the reflection. The maximum value of the energy spectrum of the spectrally restricted X-radiation 11 follows from the Bragg relation as follows: sin ⁢ ⁢ Θ = k · λ 2 · a where Θ represents the angle between the X-ray path 9 and the crystal 7 , k is a natural number and denotes the order of the reflection, I represents the wavelength of the maximum value of the energy spectrum of the spectrally restricted X-radiation 11 , and a represents a property of the crystal lattice of the crystal 7 . Bragg reflection of the X-ray by crystals produces X-radiation at a relatively narrow peak in the energy spectrum for each reflection order k. While such a narrow energy spectrum can be advantageous for many applications, it presents the problem of a relatively low radiation dose. Therefore, a widening of the energy spectrum and thus a widening of its peak in the range of the maximum value must be accepted in order to reach an accordingly increased radiation dose. For this reason, a mosaic crystal is as the preferred type of the crystal 7 for medical X-ray devices. The preferred type of the crystal 7 is a mosaic crystal made of layers of highly oriented pyrolytic graphite (HOPG). The direction in space of the crystal lattice should vary around 1°. Due to different lattice orientations of the crystal molecules or atoms represented by the factor a of the aforementioned Bragg's relation, mosaic crystals produce an energy spectrum that is widened very slightly. Spectrally restricted X-radiation with a peak widened in this manner will reach the radiation doses required in medical diagnostics. The energy spectrum of the spectrally restricted X-radiation 11 can be changed by changing the angle of incidence Θ of the X-ray 9 on the crystal 7 . For this purpose, the crystal 7 can be tilted using a positioning device that includes a tilting arrangement 13 . However, this tilting changes not only the angle of incidence Θ, but also the reflection angle. Because of this correspondent change, the ray path of the spectrally restricted X-radiation 11 changes too, so that its focus can shift. In the case of small changes in the angle of incidence Θ this effect plays only a minor role, but a substantial change of the angle can result in the focus leaving the intended (and targeted) zone of the patient 29 to be examined. This means that after larger changes occur in the energy spectrum due to the tilting of the crystal 7 , the region to be examined must be targeted again. In order to avoid this problem, the crystal 7 can be tilted simultaneously with the X-ray source 5 or with the entire arrangement of the X-ray source 5 and the monochromator 1 so that this process compensates for any change in the ray path. Since, in order to be able to target any possible section of a patient 29 to be examined, the X-ray source 5 usually is arranged so that it can be fully moved in all directions in space, all that is required to compensate for a tilting movement of the crystal 7 is to perform a coordinated tilting of the X-ray source 5 . Since the crystal 7 and the X-ray source 5 must be movable in relation to each other only in one plane, in order to influence the angle Θ, quite simple angle ratios are obtained. The simple angle ratios allow us to perform the compensation for the tilting movement of the crystal 7 either by an independent control of the tilting movement of the X-ray source 5 , or by providing a mechanism for coupling the tilting movements of the crystal 7 with the X-ray source 5 . The implementation of such possibilities is within the capabilities of those of ordinary skill in the art. The omni-directional adjustability of the X-ray source 5 can be implemented by any of a number of conventional ways. The crystal 7 can be tilted by the tilting arrangement 13 so that the angle of incidence Θ of the X-ray path 9 changes. In the illustration in the figure, the tilting motion of the crystal 7 occurs in one of the planes in the drawing plane. Due to a rigid spatial arrangement of the X-ray source 5 and the monochromator 1 , the angle Θ can be changed only by tilting the crystal 7 . However, in an alternative arrangement, the crystal 7 can be rigidly mounted in space within the monochromator 1 , and the X-ray source 5 can be tilted relative to the monochromator 1 . As previously described, in another variant the crystal 7 and the X-ray source 5 are always tilted simultaneously so that the ray path of the spectrally restricted radiation 11 remains spatially unchanged and thus the focus of the ray path does not shift. Another possible adjustment of the crystal 7 is to fully remove the crystal 7 from the X-ray path 9 or to return it using a shifting device 15 . By doing this, the influence of the crystal 7 changes so that Bragg reflection of the X-ray path 9 is quite eliminated. The X-rays in the X-ray path 9 then have the original energy spectrum determined by the X-ray source 5 and its operation parameters. The option of removing the crystal 7 allows operation either with spectrally restricted X-radiation or with unrestricted X-radiation depending on the type of the required image. In addition, removing or returning the crystal 7 to the X-ray path 9 changes the entire ray path, which can be compensated for in the above-described manner. The parameters defining the energy spectrum of the spectrally restricted X-radiation 11 are set in the control device 17 . In accordance with the invention, these parameters include, besides the X-ray voltage and the X-ray current, the tilt angle of the crystal 7 and the positioning in or outside the X-ray path 9 . The line 23 conducts the signals from the control device 17 that to control the movements of the ceiling stand 25 and positioning of the crystal 7 as well as, if necessary, of the X-ray source 5 . Thus, the control device 17 controls the positioning device, i.e., the tilting arrangement 13 , and the shifting device 15 . Therefore, the control device 17 can coordinate the tilting movement of the X-ray source 5 with the tilting movement of the crystal 7 in the above-described way so that the beam path of the X-radiation 11 remains uncharged and its focus does not shift. Selection of the angle of incidence Θ of the X-ray path 9 on the crystal 7 , should be based on a voltage as high as possible, because the efficiency of an X-ray tube used as the X-ray source 5 increases with the square of the X-ray voltage. The utilization of Bragg reflection according to the invention makes it possible to produce X-radiation of relatively low energy levels with a simultaneous high efficiency of the X-ray source 5 . In addition, the relatively high X-ray voltage reduces the blooming effect, which causes enlargement of the focal spot. In order to be able to utilize these advantageous effects enabled by the increased X-ray voltage, the incidence angle Θ is set so that the maximum value of the energy spectrum of the spectrally restricted X-radiation 11 is not greater than the 0.8-multiple of the maximum value of the energy spectrum of the X-ray 9 . Besides the maximum value of the energy spectrum in the reflected X-ray, Bragg reflection contains maxima of higher order as expressed by the factor k in the Bragg relation. In order to keep the influence of the refractions of higher order in the reflected X-ray small, the maximum value of the energy spectrum of the spectrally restricted X-radiation 11 is set to no less than the 0.34-multiple of the maximum value of the energy spectrum of the X-ray path 9 . This guarantees especially that refraction from the 3 rd order on do not enter the spectrally restricted X-radiation 11 . Adherence to the described upper and lower limits can be automatically ensured using the control device 17 . In addition, the control device 17 can automatically set the angle Θ so that after the definition of the X-ray voltage or a maximum value for the energy spectrum of the spectrally restricted X-radiation 11 or a factor between the maximum values of the energy spectrum of the X-ray path 9 and the spectrally restricted X-radiation 11 , the operation of the X-ray device occurs with optimal efficiency, as low blooming effects as possible or with other parameters optimized. In this way, the control of the monochromator 1 and the X-ray source 5 is substantially automated thus utilizing the resulting advantages, which include no need for an operator to enter special parameters. Moreover, depending on the type of the required image to be produced, the control device 17 can remove the crystal 7 from the X-ray 9 or return it. On the basis of the optical law of reflection, this invention can be used with advantage especially in applications using a fan ray, e.g., line scanners in CT apparatuses, and in applications that scan a whole area, e.g., angiography of extremities. Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of their contribution to the art.
A monochromator to be used in an X-ray device having an X-ray source is formed by a crystal for spectral restriction of X-rays produced by the X-ray source. The monochromator includes a positioning device that can move the crystal so that it changes the spectral composition of the X-radiation. The crystal can be moved so that it changes the angle between an X-ray path and the crystal, or so that the crystal is removed out of X-ray path or returned into it.
Summarize the key points of the given document.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention concerns a monochromator for an X-ray device of the type having an X-ray source with a crystal for spectral restriction of the X-ray produced by the X-ray source.", "The invention also concerns an X-ray device that incorporates such a monochromator.", "Description of the Prior Art X-rays are used in medical and technical diagnostics to obtain images of objects to be examined.", "The quality of images thus produced depends on the radiation dose and on the energy spectrum of the X-rays.", "In order to achieve a certain minimum image quality, a certain minimum radiation dose is required, and the minimum radiation dose itself depends on the spectral energy distribution in the X-rays.", "In addition, depending on the concrete body or object to be examined, there always exists an optimum level of X-radiation energy, i.e., the wavelength of the X-radiation at which a maximum contrast resolution with a simultaneous minimized radiation dose can be achieved.", "Thus, in order to achieve the requisite minimum image quality with a minimized radiation dose, X-radiation of a suitable spectrum must be used.", "The spectral energy distribution of X-rays, however, can be influenced at the X-ray source only to a limited extent.", "For example, the energy spectrum of a conventional X-ray tube always contains wavelength components outside the wavelength that is optimal for the radiation dose and the contrast resolution.", "The energy spectrum of an X-ray tube is influenced by the choice of anode material and by the type of X-ray absorption filters used.", "Furthermore, the aforementioned energy spectrum also strongly depends on the X-ray voltage, i.e., the energy with which electrons inside the X-ray tube are accelerated from the cathode to the anode.", "The X-ray voltage determines the upper limit of the energy spectrum.", "Changes in the X-ray voltage affect not only the energy spectrum, but also the radiation dose, because with decreasing X-ray voltage, the tube current, i.e., the electron flow inside the X-ray tube, decreases.", "Thus, in order to compensate for the reduction of the radiation dose with a decrease in X-ray voltage, the X-ray tube current must be increased.", "The increase of the X-ray tube current, however, is restricted by the so-called blooming effect, by which—due to a lower X-ray voltage and high X-ray currents—the X-ray focal spot on the anode of the X-ray tube enlarges.", "The blooming effect negatively affects the properties of the X-rays that are produced.", "Currently, depending on the particular application, a suitable energy spectrum is achieved by an appropriate combination of the anode material, the X-ray absorption filters, and the X-ray voltage.", "Each energy spectrum thus is necessarily a compromise among the various parameters.", "European Application 0 924 967 discloses an X-ray device with a monochromator designed on the basis of a so-called mosaic crystal.", "The mosaic crystal is arranged in the path of radiation beam in such a manner that the X-rays of the X-ray tube are reflected by it.", "On the basis of Bragg relation for the diffraction of X-rays, for a certain reflection direction spectrally restricted, i.e., quasi-monochromatized, X-rays are obtained.", "In order to obtain X-rays of various wavelengths, the aforementioned European application proposes to implement multiple mosaic crystals to provide various Bragg angles.", "The arrangement of multiple mosaic crystals and their associated diaphragms requires a number of components and is therefore costly.", "Moreover, this arrangement has the inherent drawback that different propagation paths are pre-determined for the X-rays, which have to be individually aimed at the particular object to be examined.", "SUMMARY OF THE INVENTION An object of the present invention is to provide a monochromator for an X-ray device that makes it possible to variably spectrally restrict X-rays produced by an X-ray device using a reflection crystal, with such a monochromator being inexpensive to design and easy to operate.", "The above object is achieved in accordance with the present invention by a monochromator for an X-ray device that comprises an X-ray source with a crystal for spectral restriction of the X-ray produced by the X-ray source, wherein, according to the invention, the crystal can be adjusted by a positioning device so that the energy spectrum of the spectrally restricted X-radiation can be changed.", "The ability to adjust the crystal provides the possibility of adjusting the energy spectrum of the spectrally restricted X-radiation to comply with the requirements for the image to be acquired without having to set the X-ray voltage and X-ray tube current to non-optimal values.", "For example, using this design the blooming effect that occurs at low X-ray voltages and high X-ray currents can be avoided, or the X-ray tube can always be operated with an X-ray voltage suitable for the particular requisite level of efficiency.", "At the same time, the adjustability of the crystal allows for a variable adjustment of the energy spectrum to various requirements without the need for changes in the X-ray source (for example, in the anode material).", "Consistent with conventionally-used terminology, the subject matter described herein is referred to as a “monochromator”", "even though it does not limit the X-ray radiation to a monochromatic (single energy) beam, but instead spectrally restricts the X-radiation.", "In an embodiment of the invention, the crystal is adjustable so that the angle between the X-rays (produced by the X-ray source) and the crystal can be changed.", "According to the Bragg relation, the energy spectrum of the spectrally restricted X-radiation changes dependent on the change of the diffraction angle.", "Therefore, the ability to change the angle provides a simple and inexpensive means of producing X-radiation with variable energy spectra.", "Greater changes in the angle, which can be achieved, for example, by tilting the crystal, change the entire X-ray path.", "However, such changes can be simply compensated for, e.g., by a simultaneous tilting of the X-ray source.", "The tilting of the crystal performed together with a coordinated tilting of the X-ray source allows for a simple continuous variation of the energy spectrum of X-radiation with an unchanged X-ray path.", "In another embodiment of the invention, the crystal can be adjusted so that it can be fully removed from and returned into the X-ray path produced by the X-ray source.", "If the crystal is removed from the X-ray path, Bragg diffraction of the X-ray is prevented, and the original energy spectrum of the X-ray source is reconstituted.", "Thus, the option of removing and then returning the crystal to the X-ray path provides a simple way of producing either spectrally restricted X-rays or X-rays without any spectral restriction.", "If, during the removal of the crystal, certain adjustments have to be made to reflect the change in the entire X-ray path, for example, by tilting the X-ray source, this is easy to do.", "In another embodiment of the invention, the crystal can be automatically adjusted so that we reach a maximum value of the energy spectrum of the spectrally restricted X-radiation is reached that is between 0.34- and 0.8-multiples of the maximum value of the original (unrestricted) energy spectrum of the X-ray source.", "The original energy, which is greater than in the spectrally restricted X-radiation, is produced by an increased X-ray voltage, which means the blooming effect is reduced.", "At the same time, by maintaining a minimal factor of about 0.34, the influence of higher-order reflection in the energy spectrum of the spectrally restricted X-radiation is minimized.", "Higher-order reflection occurs at double, triple, quadruple, etc.", "the minimum value of the original X-radiation.", "The indicated range rules out the possibility that reflections from the 3rd order and beyond will be contained in the spectrally restricted X-radiation.", "DESCRIPTION OF THE DRAWINGS FIG. 1 shows an X-ray device with a monochromator in accordance with this invention.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS The figure illustrates an X-ray device 3 with a monochromator 1 in accordance with the invention.", "The monochromator 1 is an accessory device that is connected to the X-ray source 5 as a module;", "however, the device can also be fully integrated with the X-ray sources.", "Other components of the X-ray tube, such as a diaphragm, are not essential to the explanation of the invention and therefore are not illustrated.", "The X-ray device 3 produces spectrally restricted X-radiation 11 in order to generate an image of a patient 29 lying on a patient positioning table 27 .", "Depending on the type of the required X-ray image, the X-ray path of X-radiation 11 can assume various orientations by moving and turning the X-ray source 5 mounted on the ceiling stand.", "This also allows examination of, for example, a standing patient, with the monochromator 1 always being used in the same manner.", "A voltage generator 19 , which is connected to the X-ray source 5 by an electrical line 23 , generates the X-ray voltage and the X-ray tube current to operate the X-ray source 5 .", "The X-ray generator 19 is controlled by a control device 17 , which is connected to the X-ray generator 19 by a control line 21 .", "The control device 17 allows entry of all the parameters of the X-ray image that is to be produced.", "The basic component of the monochromator 1 is a crystal 7 , which reflects X-rays propagating in an X-ray path 9 .", "The reflection at the crystal spectrally restricted X-radiation 11 , the energy spectrum of which depends on the angle of the reflection.", "The maximum value of the energy spectrum of the spectrally restricted X-radiation 11 follows from the Bragg relation as follows: sin ⁢ ⁢ Θ = k · λ 2 · a where Θ represents the angle between the X-ray path 9 and the crystal 7 , k is a natural number and denotes the order of the reflection, I represents the wavelength of the maximum value of the energy spectrum of the spectrally restricted X-radiation 11 , and a represents a property of the crystal lattice of the crystal 7 .", "Bragg reflection of the X-ray by crystals produces X-radiation at a relatively narrow peak in the energy spectrum for each reflection order k. While such a narrow energy spectrum can be advantageous for many applications, it presents the problem of a relatively low radiation dose.", "Therefore, a widening of the energy spectrum and thus a widening of its peak in the range of the maximum value must be accepted in order to reach an accordingly increased radiation dose.", "For this reason, a mosaic crystal is as the preferred type of the crystal 7 for medical X-ray devices.", "The preferred type of the crystal 7 is a mosaic crystal made of layers of highly oriented pyrolytic graphite (HOPG).", "The direction in space of the crystal lattice should vary around 1°.", "Due to different lattice orientations of the crystal molecules or atoms represented by the factor a of the aforementioned Bragg's relation, mosaic crystals produce an energy spectrum that is widened very slightly.", "Spectrally restricted X-radiation with a peak widened in this manner will reach the radiation doses required in medical diagnostics.", "The energy spectrum of the spectrally restricted X-radiation 11 can be changed by changing the angle of incidence Θ of the X-ray 9 on the crystal 7 .", "For this purpose, the crystal 7 can be tilted using a positioning device that includes a tilting arrangement 13 .", "However, this tilting changes not only the angle of incidence Θ, but also the reflection angle.", "Because of this correspondent change, the ray path of the spectrally restricted X-radiation 11 changes too, so that its focus can shift.", "In the case of small changes in the angle of incidence Θ this effect plays only a minor role, but a substantial change of the angle can result in the focus leaving the intended (and targeted) zone of the patient 29 to be examined.", "This means that after larger changes occur in the energy spectrum due to the tilting of the crystal 7 , the region to be examined must be targeted again.", "In order to avoid this problem, the crystal 7 can be tilted simultaneously with the X-ray source 5 or with the entire arrangement of the X-ray source 5 and the monochromator 1 so that this process compensates for any change in the ray path.", "Since, in order to be able to target any possible section of a patient 29 to be examined, the X-ray source 5 usually is arranged so that it can be fully moved in all directions in space, all that is required to compensate for a tilting movement of the crystal 7 is to perform a coordinated tilting of the X-ray source 5 .", "Since the crystal 7 and the X-ray source 5 must be movable in relation to each other only in one plane, in order to influence the angle Θ, quite simple angle ratios are obtained.", "The simple angle ratios allow us to perform the compensation for the tilting movement of the crystal 7 either by an independent control of the tilting movement of the X-ray source 5 , or by providing a mechanism for coupling the tilting movements of the crystal 7 with the X-ray source 5 .", "The implementation of such possibilities is within the capabilities of those of ordinary skill in the art.", "The omni-directional adjustability of the X-ray source 5 can be implemented by any of a number of conventional ways.", "The crystal 7 can be tilted by the tilting arrangement 13 so that the angle of incidence Θ of the X-ray path 9 changes.", "In the illustration in the figure, the tilting motion of the crystal 7 occurs in one of the planes in the drawing plane.", "Due to a rigid spatial arrangement of the X-ray source 5 and the monochromator 1 , the angle Θ can be changed only by tilting the crystal 7 .", "However, in an alternative arrangement, the crystal 7 can be rigidly mounted in space within the monochromator 1 , and the X-ray source 5 can be tilted relative to the monochromator 1 .", "As previously described, in another variant the crystal 7 and the X-ray source 5 are always tilted simultaneously so that the ray path of the spectrally restricted radiation 11 remains spatially unchanged and thus the focus of the ray path does not shift.", "Another possible adjustment of the crystal 7 is to fully remove the crystal 7 from the X-ray path 9 or to return it using a shifting device 15 .", "By doing this, the influence of the crystal 7 changes so that Bragg reflection of the X-ray path 9 is quite eliminated.", "The X-rays in the X-ray path 9 then have the original energy spectrum determined by the X-ray source 5 and its operation parameters.", "The option of removing the crystal 7 allows operation either with spectrally restricted X-radiation or with unrestricted X-radiation depending on the type of the required image.", "In addition, removing or returning the crystal 7 to the X-ray path 9 changes the entire ray path, which can be compensated for in the above-described manner.", "The parameters defining the energy spectrum of the spectrally restricted X-radiation 11 are set in the control device 17 .", "In accordance with the invention, these parameters include, besides the X-ray voltage and the X-ray current, the tilt angle of the crystal 7 and the positioning in or outside the X-ray path 9 .", "The line 23 conducts the signals from the control device 17 that to control the movements of the ceiling stand 25 and positioning of the crystal 7 as well as, if necessary, of the X-ray source 5 .", "Thus, the control device 17 controls the positioning device, i.e., the tilting arrangement 13 , and the shifting device 15 .", "Therefore, the control device 17 can coordinate the tilting movement of the X-ray source 5 with the tilting movement of the crystal 7 in the above-described way so that the beam path of the X-radiation 11 remains uncharged and its focus does not shift.", "Selection of the angle of incidence Θ of the X-ray path 9 on the crystal 7 , should be based on a voltage as high as possible, because the efficiency of an X-ray tube used as the X-ray source 5 increases with the square of the X-ray voltage.", "The utilization of Bragg reflection according to the invention makes it possible to produce X-radiation of relatively low energy levels with a simultaneous high efficiency of the X-ray source 5 .", "In addition, the relatively high X-ray voltage reduces the blooming effect, which causes enlargement of the focal spot.", "In order to be able to utilize these advantageous effects enabled by the increased X-ray voltage, the incidence angle Θ is set so that the maximum value of the energy spectrum of the spectrally restricted X-radiation 11 is not greater than the 0.8-multiple of the maximum value of the energy spectrum of the X-ray 9 .", "Besides the maximum value of the energy spectrum in the reflected X-ray, Bragg reflection contains maxima of higher order as expressed by the factor k in the Bragg relation.", "In order to keep the influence of the refractions of higher order in the reflected X-ray small, the maximum value of the energy spectrum of the spectrally restricted X-radiation 11 is set to no less than the 0.34-multiple of the maximum value of the energy spectrum of the X-ray path 9 .", "This guarantees especially that refraction from the 3 rd order on do not enter the spectrally restricted X-radiation 11 .", "Adherence to the described upper and lower limits can be automatically ensured using the control device 17 .", "In addition, the control device 17 can automatically set the angle Θ so that after the definition of the X-ray voltage or a maximum value for the energy spectrum of the spectrally restricted X-radiation 11 or a factor between the maximum values of the energy spectrum of the X-ray path 9 and the spectrally restricted X-radiation 11 , the operation of the X-ray device occurs with optimal efficiency, as low blooming effects as possible or with other parameters optimized.", "In this way, the control of the monochromator 1 and the X-ray source 5 is substantially automated thus utilizing the resulting advantages, which include no need for an operator to enter special parameters.", "Moreover, depending on the type of the required image to be produced, the control device 17 can remove the crystal 7 from the X-ray 9 or return it.", "On the basis of the optical law of reflection, this invention can be used with advantage especially in applications using a fan ray, e.g., line scanners in CT apparatuses, and in applications that scan a whole area, e.g., angiography of extremities.", "Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of their contribution to the art." ]
CROSS REFERENCES TO RELATED APPLICATIONS This is a continuation, of application Ser. No. 41,675, filed May 22, 1970 which in turn is a continuation-in-part of U.S. patent application Ser. No. 519,841, filed Jan. 11, 1966. BACKGROUND OF THE INVENTION 1. Field of the Invention This application discloses a process for epoxidizing allyl alcohol with peracetic acid in an essentially anhydrous, inert, organic solvent, and hydrolyzing the epoxidized reaction product, glycidol, to form glycerol. When desired, the hydrolysis step can be omitted and glycidol can be recovered as product. 2. Description of the Prior Art Glycerol is manufactured from allyl alcohol by two principal processes: chlorohydrination followed by hydrolysis of the intermediate "glycerol chlorohydrin," and by hydroxylation with hydrogen peroxide. Both processes involve difficulties in refining the glycerol to obtain a product of marketable quality. U.S. Pat. No. 2,960,447, for example, discloses a detailed procedure involving multiple distillations at controlled pH as a way to purify glycerol derived from allyl alcohol hydroxylation. Epoxidations of unsaturated organic compounds by organic peracids are generally conducted with one reactant present in a substantial excess in order to obtain acceptable reaction rates and efficiencies. Epoxidation of low molecular weight unsaturated organic compounds, such as allyl alcohol, with organic peracids produces undesirable by-products because of reaction of the epoxide in the presence of the carboxylic acid co-products. A method of avoiding these difficulties is suggested by British patent specification No. 837,464 which reacts allyl alcohol and hydrogen peroxide in an aqueous solution, the pH of which is controlled by a minor concentration of an inorganic or organic alkaline-reacting substance. This patent suggests using organic compounds, notably amines, which impart to an aqueous solution an alkaline pH, as the preferred means for accomplishing this end. The reaction of the peroxide with allyl alcohol produces glycidol in a dilute aqueous reaction medium containing catalyst and the added amine; although the glycidol can be converted to glycerol by heating such a mixture, isolation of pure glycidol becomes a difficult problem. This British specification discusses the art-recognized problem of epoxidizing unsaturated compounds with organic peracids, that is, that considerable by-product formation occurs with a diminished yield of epoxide. German Pat. No. 1,081,462, describes epoxidation of high molecular weight unsaturated materials with percarboxylic acids in a diluent (using reduced temperature and pressure to distill acetic acid and volatile materials away from the reaction mixture.) The process operates under conditions such that acetic acid and volatile materials are continuously distilled away from the mixture. This process is not suitable for the epoxidation of allyl alcohol as allyl alcohol is more volatile than either peracetic or acetic acids and is therefore removed from the reaction zone before any substantial conversion to glycidol occurs. SUMMARY OF THE INVENTION We have now discovered a process for manufacturing glycidol, and, if desired, glycerol in high yields and purity comprising: (a) epoxidizing allyl alcohol in a reaction zone at a temperature of 25° to 100° C. using peracetic acid in solution in a substantially anhydrous, inert organic solvent containing between 5 and 40% peracetic acid, the ratio of allyl alcohol to peracetic acid being between 5 and 0.7 moles of allyl alcohol per mole of peracetic acid, until at least 70 to about 95% of the reactant present in less than stoichiometric amount is reacted to form a mixture of glycidol, solvent, co-product acetic acid, allyl alcohol, peracetic acid and some high boiling impurities; (b) subjecting the reaction mixture to a sequence of distillations to rapidly and continuously separate acetic acid from glycidol and then recover glycidol as a distillate; (c) subsequently hydrolyzing glycidol to glycerol using 10 to 100 moles of water per mole of glycidol at a temperature between 20° and 180° C. and recovering glycerol. Where desired, glycidol may be obtained in high yields by omitting the hydrolysis step and simply recovering glycidol. The glycidol may be recovered from the mixture of reaction products as a commercial product which can be used as a chemical intermediate. This high quality glycidol can also be hydrolyzed to produce an aqueous glycerol which can be purified without employing the extensive refining procedures heretofore encountered in the synthetic production of pure glycerol by prior art processes. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram for the overall process using a low boiling solvent and no diluent. FIG. 2 is a schematic diagram for the process using a low boiling solvent and a diluent, but omitting the hydrolysis step. FIG. 3 is a schematic diagram for the process using a high boiling solvent and no diluent, but omitting the hydrolysis step. DESCRIPTION OF THE PREFERRED EMBODIMENTS The epoxidation of allyl alcohol by peracetic acid may be a batch or a continuous process. An excess of one reactant is desirable in order to increase the reaction rate. Allyl alcohol is preferred as the reactant to be used in excess, since allyl alcohol is more readily recoverable than peracetic acid. Peracetic acid is used in solution in a substantially anhydrous, inert, solvent, preferably a ketone, ester or aromatic hydrocarbon whose boiling point may vary from about 45° to about 180° C. Other solvents can also be used, the primary requirement being that they be inert to peracetic acid as well as to glycidol and acetic acid under the conditions employed. The solvent should be separable from allyl alcohol and acetic acid by distillation or other reasonable methods. The solvent should either be substantially lower boiling than glycidol and easily separable therefrom, or should form an azeotropic mixture with glycidol, or be higher boiling than glycidol if non-azeotropic. Solvents forming azeotropes with glycidol are of particular value. Various solvents meet these requirements, for example, acetone, ethyl acetate, o-xylene, pseudocumene, monochlorobenzene, ortho-dichlorobenzene, diisobutyl ketone, butyl butyrate, methyl ethyl ketone, isopropyl acetate, methylal, dioxane and halogenated solvents containing not more than six carbon atoms such as chloroform, carbon tetrachloride, perchloroethylene, and fluorinated alkanes. Particularly preferred solvents are acetone, pseudocumene and diisobutyl ketone. Generally, the peracetic acid content of the solution is between 5 and 40%, this upper limit being a consequence of the explosion hazard associated with too highly concentrated peracetic acid. Peracetic acid concentrations below 5% can be used, however, such dilutions are unattractive in a commercial operation. As a consequence of its preparation the peracetic solution will usually contain a small amount of acetic acid, e.g., 5 to 10% is a common tolerable amount. The rate at which the allyl alcohol is epoxidized increases with increasing temperatures. For best operation of the process temperature may be between about 25° and 100° C., and is preferably between about 40° and 65° C. Although elevated pressures can be employed to make possible operation at temperatures above the normal boiling point of the system, no overall advantage follows as the reaction is preferably conducted at atmospheric pressure. Variation of the reaction rate with temperature is illustrated by the 40 hours required for completion of the reaction at room temperature, as compared with completion in a period between 21/2 to 4 hours at 60° C., when the process is operated as a batch process. We have found that the reaction rate decreases sharply as the percent conversion of the minor reactant increases to a level above 75%, and particularly above 85%. The reaction carried out at 45° C., using 3:1 molar ratio of allyl alcohol to peracetic acid, results in 90% peracetic acid conversion in 3.5 hours. After 5 hours the conversion is about 93%. In most cases nearly quantitative yields of glycidol based on allyl alcohol are obtained. Due to these diminishing reaction rates, it is preferable to terminate the epoxidation reaction at some point prior to exhaustion of either of the reactants and to further epoxidize in a second stage. We have found that residual peracetic acid and allyl alcohol further react in the glycidol separation unit. This is utilized advantageously to accomplish a second stage epoxidation in the glycidol separation unit, and, in effect, combine this operation with the glycidol purification. Although the percentage conversion to which the epoxidation reaction is carried in the first stage varies depending upon the reaction conditions and equipment utilized, it is preferred that it should be within the range of between about 70 and 95% of the minor reactant. Various process options are available. The process, for example, may be operated using a low boiling solvent with no diluent, a low boiling solvent with the addition of another solvent which acts as a diluent, or a high boiling solvent alone. The process for the preparation of glycerol using a low boiling solvent is described with reference to FIG. 1. Allyl alcohol is fed through line 1 to reactor 21. Peracetic acid at 5 to 40% and preferably 15-25% weight concentration in a substantially anhydrous, inert, solvent, such as ethyl acetate or acetone, is fed through line 2 to reactor 21, where the reaction mixture is maintained at a temperature between 35° and 70° C. The peracetic acid solution usually contains 5-10% of acetic acid. The crude mixture of reaction products containing glycidol is drawn through line 3 and fed to distillation column 22 which is maintained at reduced pressure. The organic solvent is vaporized and removed through line 4. In the column we prefer, when using acetone as the solvent, to maintain the vapor temperatures at about 24° C., the bottom of column 22 operating at 170 mm. of Hg. will be at a temperature of about 80° C. with an underflow composed of acetic acid, glycidol and a small amount of the solvent. This mixture is withdrawn through line 5 and fed rapidly and continuously to column 23 operating at a low overhead pressure, e.g., about 17mm. of Hg. Acetic acid and unreacted allyl alcohol are removed through line 6 at a vapor temperature of about 29° C. The lower section of the column operating at about 65° C. collects high boiling materials (acetins, glycidol polymerization products, etc.) which are removed as an underflow through line 8 and product glycidol is removed at an intermediate stage through line 7 and condensed in condenser 24. When glycidol is removed through line 7 the reboiler temperature is above 120° C. Reaction between glycidol and acetic acid is minimized by operating so that once the solvent is removed in column 22 the products acetic acid and glycidol are rapidly and continuously separated at as low a temperature as is practicable. The glycidol may also be removed through line 8 as an impure product, with a reboiler temperature of 65° to 90° C. In this case it can be purified in a second distillation column, not illustrated, placed between column 23 and condenser 24. The product glycidol is then fed through line 9 to a hydrolyzer 25, where water is supplied through line 11, and temperature is maintained at about 100° C. A 10 to 20% solution of glycerol in water is drawn off through line 10 and fed to a concentrator, 26. Water from the concentrator 26 is recycled to hydrolyzer 25 through lines 12, and 11. Glycerol containing 1 to 2% water is taken from evaporator 26 through line 13 and fed to column 27 operating at 5 mm. Hg., where light impurities are taken from the head through line 14. Pure glycerol is removed as a vapor through line 15. The process for the preparation of glycerol or glycidol using a low boiling solvent and diluent is described with reference to FIG. 2. Allyl alcohol is fed through line 59 to reactor 30. Peracetic acid at 5 to 40% and preferably 15 to 25% weight concentration in substantially anhydrous, inert, solvent, such as ethyl acetate or acetone, is fed through line 58 to reactor 30, where the reaction mixture is maintained at a temperature between 35° and 70° C. The peracetic acid solution usually contains 5-10% peracetic acid. The diluent, such as xylenes, monochlorobenzene, ethylbenzene, pseudocumene or diisobutyl ketone, is introduced with or near the epoxidation feed to column 32. The diluent is preferably added through line 57 to the feed line 51 just prior to the entry of the feed line into column 32 which is maintained at reduced pressure. The organic solvent is vaporized and removed through line 59. When acetone is used as the solvent, column 32 is operated at an overhead pressure of about 130mm. Hg. The low boiling solvent such as acetone, passes overhead and the underflow, also containing the diluent, is then fed through line 52 to column 34 from which allyl alcohol, acetic acid and traces of peracetic acid are taken overhead. Pressure at the top of the column is maintained at about 50 mm. of Hg., the temperature of the overhead vapor at about 50° C. and the reboiler at about 90° C. Some diluent may go overhead with the allyl alcohol, acetic acid and traces of peracetic acid. Reaction between glycidol and acetic acid is substantially prevented by the fact that in column 34 the products acetic acid and glycidol are rapidly and continuously separated. Glycidol and diluent are withdrawn from the lower portion of column 34 and fed to column 36. Many diluents, such as pseudocumene, form an azeotropic mixture with glycidol so that an azeotropic composition can be removed overhead from column 36. This actually constitutes an advantage since the amount of diluent used is well in excess of that required to satisfy the azeotrope, so that complete removal of glycidol from the column underflow of column 36 is insured by operating so that a small excess of diluent over the azetropic requirement is removed with the glycidol. The glycidol-azeotrope leaves through line 55 and goes to the recovery unit. The underflow from column 36 flows through line 56 to column 38 where the diluent is removed overhead through line 60 and returned to the process. High boilers are removed as an underflow from column 38. The glycidol-diluent azeotrope recovered from column 36 through line 55 may be treated in several ways. Pure glycidol can be separated by breaking the azeotrope and separating glycidol for use as a chemical intermediate. The azeotropic mixture can be subjected directly to hydrolysis conditions if the solvent selected is stable under the conditions of hydrolysis employed and separable from the hydroysate. Hydrolysis of the azeotropic mixture proceeds readily; the glycerol partitions into the aqueous phase so that the diluent can be decanted off for recycle to the system leaving the aqueous phase to be concentrated and the glycerol subsequently refined. The process employing a high boiling solvent and no diluent is described with reference to FIG. 3. Allyl alcohol is fed to reactor 40 through line 88. Peracetic acid at 5 to 40% weight concentration in an inert high boiling solvent such as diisobutyl ketone, is fed through line 87 to reactor 40 where the reaction mixture is maintained at a temperature between 35° and 70° C. The peracetic acid solution usually contains 5 to 10% acetic acid. An excess of alcohol is preferred. The epoxidation reaction is carried to substantially complete conversion of the minor reactant, and the mixture is then fed from the epoxidizer through line 81 to column 42 wherein acetic acid, surviving peracetic acid and allyl alcohol are removed overhead. This column is kept operating at an overhead pressure of about 40 mm. of Hg., a feed plate temperature of about 75° C. and reboiler temperature of about 92° C. when using diisobutyl ketone as the solvent. The glycidol-high boiling solvent solution is removed from column 42 as an underflow through line 82 and fed to column 44. Reaction between glycidol and acetic acid is largely prevented by the fact that in column 42 the products acetic acid and glycidol are rapidly and continuously separated. In column 44, when using diisobutyl ketone as the solvent, the column is operated with an overhead pressure of about 50 mm. of Hg. and a vapor temperature of about 78° C. when the reboiler is operated at about 88° to 92° C. Glycidol is removed as a vapor through line 85. When diisobutyl ketone is used as the solvent, the glycidol is obtained in the form of the azeotrope with diisobutyl ketone. The glycidol-solvent mixture may be fed directly to the hydrolyzer along with the requisite amount of water, and the mixture held at reaction temperature until hydrolysis is complete. The mixture is then cooled and, when diisobutyl ketone is used as the solvent, the solvent is decanted from the aqueous glycerol mixture and returned to the process. The glycerol is concentrated and refined by conventional methods. The glycidol-solvent mixture leaving column 44 through line 85 can, if desired, be processed to recover product glycidol. The underflow from column 44 containing solvent leaves through line 83 and is fed to column 46. Column 46 is operated to separate the solvent, which is returned to the process, from high boilers which leave the process through line 89. The processes of this invention are further illustrated in the following examples which are given by way of example and not by way of limitation to illustrate the invention to those skilled in the art. All parts and percentages are by weight unless otherwise specified. EXAMPLE 1 The equipment consisted of a 12-liter resin flask fitted with an aluminum cooling coil, containing a seven-neck head equipped with a condenser, mechanical stirrer, thermometer, two addition funnels, and the inlet and outlet for the cooling coil. The charge consisted of about 12 moles of peracetic acid as a 15-30% solution in acetone containing 6-8% acetic acid and the appropriate quantity of allyl alcohol, as shown in the table. The peracetic acid and allyl alcohol were added to the reactor simultaneously through the addition funnels over a period of 39 minutes. The reactant ratios, temperatures, reaction time, allyl alcohol conversions, and glycidol yields (based on allyl alcohol) are given in the following table: ______________________________________Moles allyl Peracetic Allyl alco- Glycidolalcohol per Time, Conc. Temp. hol conver- Yield,mole peracid hours % ° C. sion, % %______________________________________A 0.77 2.0 19.8 69 92.7 94.5B 1.3 3.0 20.3 55 65.1 95.8C 1.3 4.0 15.0 55 64.2 92.6D 2.0 6.0 20.0 45 45.9 100.E 3.0 3.75 30.0 55 31.8 100.______________________________________ F. 346 parts of a solution obtained from A of this example were fed at 3.5 milliliters per minute to the mid-point of a rectification column operated at 100 millimeters Hg. pressure. The actone was taken off overhead and contained less than 1 percent acetic acid and no glycidol. The underflow from the column contained 98% of the glycidol fed to the column. This crude glycidol was then fed to a column operated at 29 millimeters Hg. Acetic acid was removed overhead together with unconverted allyl alcohol. The high boiling components were withdrawn from the bottom, and at a level one plate above the reboiler section a vapor was withdrawn and condensed to give glycidol containing one percent acetic acid, representing 98.5% of the glycidol in the feed. G. A mixture of 432 parts of water, one part of 90% formic acid and 72 parts of glycidol obtained from operation "F" of this example was heated at 60° C. for 4 hours at which time all the glycidol had been consumed. Water was then removed by evaporation and the glycerol was distilled through a short column at 15 millimeters Hg. The fraction distilling over the range of 167°-172° C. consisted of 86 parts and represented a 96% yield of glycerol based on the glycidol charged. The product obtained in this manner meets commercial specifications. Similar results are obtained using this procedure by substituting for acetone: ethyl acetate, methylal, benzene and chloroform. EXAMPLE 2 An epoxidation vessel was charged with allyl alcohol (2668 g., 99.1 percent assay, 45.52 moles) which was heated to 45° C. To this was added a solution of peracetic acid in acetone (5390 g. of 21.4 percent peracetic acid, 15.18 moles) during 10 minutes while cooling to maintain a temperature of 45° C. The mixture was then held at 45° C and sampled at intervals to determine the conversion of peracetic acid. After approximately 3 hours, the peracetic acid conversion was 93.9 percent; 13.71 moles of allyl alcohol had been consumed and 13.01 moles of glycidol appeared for an alcohol reaction efficiency of 94.9 percent. The mixture was held for an additional hour at 45° C., then rapidly cooled to 12° C. The epoxidation mixture (7444 g.) was diluted with pseudocumene (3722 g.) and the mixture was fed, at a rate of 62.1 g/minute to a 2-inch Oldershaw distillation column, constituted in descending order as follows: refrigerated condenser, magnetic reflux head, 10-tray section, feed section, 5-tray section, temperature sensor, reboiler. Feed composition was as follows: ______________________________________Component Weight percent______________________________________Acetone 33.3Allyl alcohol 14.8Acetic acid 9.77Glycidol 8.09High boilers 0.67Pseudocumene 33.3______________________________________ Pressure at the top of the column was 75 mm. Hg.; column temperatures were: overhead vapor, 6°-6.5° C.; feed plate, 32°-33.5° C.; reboiler, 61.5°-62.5° C. The reflux ratio was 1:1. From a total feed of 11.166 g., there were obtained 3,664 g. of distillate and 7.502 g. of underflow of the following weight percent compositions: ______________________________________Component Distillate, 3.664 g. Underflow, 7.502 g.______________________________________Acetone 98.1 0.8Allyl alcohol 0.8 21.6Acetic Acid 0.02 14.45Glycidol 0.1 11.84Pseudocumene -- 50.3Unidentified 1.0 --High boilers -- 1.0______________________________________ Recovery of glycidol was 98.3 percent. The underflow (7,473 g.) from the acetone removal column was fed at a rate of 40 g./minute to a 2-inch Oldershaw column constituted as follows: water-cooled condenser, magnetic reflux head, 10-tray section, temperature sensor, 10-tray section, feed section, 25 tray section, reboiler. Pressure at the top of the column ws 50 mm. of Hg.; reflux ratio was 1:1. Column temperatures were: overhead vapor, 47.5° C.; 10th tray 51.5° C.; feed tray 60° C; reboiler 90° C. Column effluent weight percent compositions were as follows: ______________________________________Component Distillate (2,768 g.) Underflow (4,802 g.)______________________________________Acetic acid 34.78 1.27Glycidol 0.15 18.28Pseudocumene 4.4 78.8High boilers -- 1.6Allyl Alcohol 58.31 --Acetone 2.17 --______________________________________ Recovery of glycidol across this column was 99.2 percent. Recovery of glycidol azeotrope from the underflow of the acetic acid removal column was achieved by feeding the underflow to a 1 -inch Oldershaw column constituted in descending order as follows: water-cooled condenser, magnetic reflux head (set at 1:1), 5-trays, feed section, 5-trays, reboiler. At a column head pressure of 60 mm., the vapor temperature was 75.5° C., the reboiler temperature was 89° C. From 4,160 g. of feed, there were obtained 2,082 g. of distillate containing 33.0 percent glycidol and 2,050 g. of underflow containing 2.56 percent glycidol. EXAMPLE 3 Epoxidation was conducted by reacting allyl alcohol with 15 percent peracetic acid in acetone at a ratio of 1.3 moles allyl alcohol/mole of peracetic acid. Peracetic acid conversion was carried to 90 percent. The reaction mixture was then diluted with pseudocumene to give a mixture which was fed to an acetone removal column. In the following discussion, each component rate through the system is shown in pounds per hour. The column consisted of: water-cooled condenser, reflux head (1:1 reflux), 10-trays, feed section, 10-trays, reboiler. Overhead pressure was 400 mm. Hg., temperature 40° C.; reboiler pressure was 415 mm. Hg., temperature 109° C. Feed composition (lb/hr.) was: acetone, 24.13; allyl alcohol, 1,382; peracetic acid, 0.452; acetic acid, 4.722; glycidol, 3.767; high boilers, 0.200; pseudocumene, 30.13. Overhead was taken: acetone, 24.08; allyl alcohol, 0.121. The underflow consisted of: acetone, 0.042; allyl alcohol, 0.915; peracetic acid, nil; acetic acid, 5.080; glycidol, 4.169; high boilers, 0.243; pseudocumene, 30.13. The underflow from the acetone removal column was fed to the acetic acid removal column, consisting of: water-cooled condenser, reflux head (2:1 reflux ratio), 30-trays, feed section, 20-trays, reboiler. Overhead pressure was 50 mm. Hg., temperature 46.5° C.; reboiler pressure was 88 mm. Hg., temperature, 90° C. Overhead was taken: acetone, 0.042; allyl alcohol, 0.915; acetic acid, 5.011; glycidol, 0.0065; pseudocumene, 0.314. The underflow consisted of: acetic acid, 0.0684; glycidol, 4.15; high boilers, 0.255; pseudocumene, 29.82. The underflow from the acetic acid removal column was fed to the glycidol azeotrope column which consisted of: water-cooled condenser, reflux head (2:1 reflux ratio), 5-trays, feed section, 10-trays. Overhead pressure was 60 mm. Hg., temperature, 80° C.; reboiler pressure was 70 mm. Hg., temperature 93° C. Overhead was taken: acetic acid, 0.0684; glycidol, 4.150; pseudocumene, 8.428. The underflow consisted of high boilers, 0.255; pseudocumene, 21.39. Pseudocumene was recovered from the underflow for recycle by simple distillation. EXAMPLE 4 A solution of peracetic acid, 7.70 percent (32.1 moles), and acetic acid, 3.55 percent (20.6 moles) in diisobutyl ketone was treated with allyl alcohol (41.7 moles) at 50° C. for 2.5 hours, then held at 57° -58° C. for another 3 hours. At the end of this time, the conversion of peracetic acid was 94.0 percent with an indicated reaction efficiency to glycidol of 92.4 percent based on allyl alcohol and 86.2 percent based on peracetic acid. The epoxidation mixture was fed at a rate of 35.8 g./min. to a 2-inch Oldershaw column constituted as follows: water-cooled condenser, reflux head (6:1 reflux ratio), 10-trays, temperature sensor, 10-trays, feed section, 30-trays, reboiler. Overhead pressure was 38 mm. Hg., temperature, 35.5° -36.0° C. Feed-plate temperature was 74° C., reboiler temperature, 91.5° -92° C. Approximately 12.5 percent of the feed was taken overhead and contained the following: allyl alcohol, 13.46 moles; acetic acid, 50.55 moles, corresponding to an efficiency of 94.9 percent based on total acids charged to the epoxidation. The underflow from the acetic acid removal column, containing 0.14 percent acetic acid, was fed at 44 g./min. to the glycidol azeotrope column which consisted of a 2-inch Oldershaw, arranged as follows: water-cooled condenser, reflux head (2:1 reflux ratio), 5-trays, feed section, 10-trays, reboiler. Overhead pressure was 50 mm.. Hg. and the vapor temperature was 77.5° -78° C. The reboiler operated at 89° -91° C. Approximately 28.5 percent of the feed was taken overhead, and contained 29.9 percent glycidol (corresponding to 25.03 moles), 0.48 percent acetic acid. Only 0.03 percent glycidol was contained in the underflow. The recovery of glycidol corresponds to an efficiency of 88.7 percent based on unrecovered allyl alcohol. The underflow from the glycidol azeotrope column was flash distilled to recover the diisobutyl ketone for recycle. EXAMPLE 5 An agitated reaction vessel was charged with 9,125 g. of water which was heated to reflux. To this was added at a rate of 50 ml./min. 3,050 g. of a solution of glycidol (29.92%, 912.5 g., 12.33 moles) and acetic acid (0.35%, 10.7 g., 0.178 mole) in diisobutyl ketone which had been obtaind by azeotropic distillation. After completion of the glycidol addition, the mixture was held under reflux for another 3 hours. After cooling, the diisobutyl ketone layer which separated was decanted from the aqueous glycerol and recycled to the process. The glycerol content of the aqueous hydrolysate was 10.9 percent corresponding to a crude yield of 96 percent. The pH of the solution was adjusted by the addition of 0.2 mole of sodium hydroxide, and the solution was concentrated to give 1,172 g. of crude glycerol. This was distilled at reduced pressure to give refined glycerol meeting commercial specifications. As will be apparent to those skilled in the art, numerous modifications and variations of the embodiments illustrated above may be made without departing from the spirit of the invention or the scope of the following claims.
This application discloses a process for manufacturing glycidol and, if desired, glycerol, by epoxidizing allyl alcohol with a 5 to 40% solution of peracetic acid in a substantially anhydrous, inert, organic solvent to produce glycidol in high yield and purity. Formation of by-products is minimized by rapid removal of co-product acetic acid. The glycidol can then be hydrolyzed to form a readily purifiable glycerol.
Identify and summarize the most critical technical features from the given patent document.
[ "CROSS REFERENCES TO RELATED APPLICATIONS This is a continuation, of application Ser.", "No. 41,675, filed May 22, 1970 which in turn is a continuation-in-part of U.S. patent application Ser.", "No. 519,841, filed Jan. 11, 1966.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention This application discloses a process for epoxidizing allyl alcohol with peracetic acid in an essentially anhydrous, inert, organic solvent, and hydrolyzing the epoxidized reaction product, glycidol, to form glycerol.", "When desired, the hydrolysis step can be omitted and glycidol can be recovered as product.", "Description of the Prior Art Glycerol is manufactured from allyl alcohol by two principal processes: chlorohydrination followed by hydrolysis of the intermediate "glycerol chlorohydrin,"", "and by hydroxylation with hydrogen peroxide.", "Both processes involve difficulties in refining the glycerol to obtain a product of marketable quality.", "U.S. Pat. No. 2,960,447, for example, discloses a detailed procedure involving multiple distillations at controlled pH as a way to purify glycerol derived from allyl alcohol hydroxylation.", "Epoxidations of unsaturated organic compounds by organic peracids are generally conducted with one reactant present in a substantial excess in order to obtain acceptable reaction rates and efficiencies.", "Epoxidation of low molecular weight unsaturated organic compounds, such as allyl alcohol, with organic peracids produces undesirable by-products because of reaction of the epoxide in the presence of the carboxylic acid co-products.", "A method of avoiding these difficulties is suggested by British patent specification No. 837,464 which reacts allyl alcohol and hydrogen peroxide in an aqueous solution, the pH of which is controlled by a minor concentration of an inorganic or organic alkaline-reacting substance.", "This patent suggests using organic compounds, notably amines, which impart to an aqueous solution an alkaline pH, as the preferred means for accomplishing this end.", "The reaction of the peroxide with allyl alcohol produces glycidol in a dilute aqueous reaction medium containing catalyst and the added amine;", "although the glycidol can be converted to glycerol by heating such a mixture, isolation of pure glycidol becomes a difficult problem.", "This British specification discusses the art-recognized problem of epoxidizing unsaturated compounds with organic peracids, that is, that considerable by-product formation occurs with a diminished yield of epoxide.", "German Pat. No. 1,081,462, describes epoxidation of high molecular weight unsaturated materials with percarboxylic acids in a diluent (using reduced temperature and pressure to distill acetic acid and volatile materials away from the reaction mixture.) The process operates under conditions such that acetic acid and volatile materials are continuously distilled away from the mixture.", "This process is not suitable for the epoxidation of allyl alcohol as allyl alcohol is more volatile than either peracetic or acetic acids and is therefore removed from the reaction zone before any substantial conversion to glycidol occurs.", "SUMMARY OF THE INVENTION We have now discovered a process for manufacturing glycidol, and, if desired, glycerol in high yields and purity comprising: (a) epoxidizing allyl alcohol in a reaction zone at a temperature of 25° to 100° C. using peracetic acid in solution in a substantially anhydrous, inert organic solvent containing between 5 and 40% peracetic acid, the ratio of allyl alcohol to peracetic acid being between 5 and 0.7 moles of allyl alcohol per mole of peracetic acid, until at least 70 to about 95% of the reactant present in less than stoichiometric amount is reacted to form a mixture of glycidol, solvent, co-product acetic acid, allyl alcohol, peracetic acid and some high boiling impurities;", "(b) subjecting the reaction mixture to a sequence of distillations to rapidly and continuously separate acetic acid from glycidol and then recover glycidol as a distillate;", "(c) subsequently hydrolyzing glycidol to glycerol using 10 to 100 moles of water per mole of glycidol at a temperature between 20° and 180° C. and recovering glycerol.", "Where desired, glycidol may be obtained in high yields by omitting the hydrolysis step and simply recovering glycidol.", "The glycidol may be recovered from the mixture of reaction products as a commercial product which can be used as a chemical intermediate.", "This high quality glycidol can also be hydrolyzed to produce an aqueous glycerol which can be purified without employing the extensive refining procedures heretofore encountered in the synthetic production of pure glycerol by prior art processes.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram for the overall process using a low boiling solvent and no diluent.", "FIG. 2 is a schematic diagram for the process using a low boiling solvent and a diluent, but omitting the hydrolysis step.", "FIG. 3 is a schematic diagram for the process using a high boiling solvent and no diluent, but omitting the hydrolysis step.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS The epoxidation of allyl alcohol by peracetic acid may be a batch or a continuous process.", "An excess of one reactant is desirable in order to increase the reaction rate.", "Allyl alcohol is preferred as the reactant to be used in excess, since allyl alcohol is more readily recoverable than peracetic acid.", "Peracetic acid is used in solution in a substantially anhydrous, inert, solvent, preferably a ketone, ester or aromatic hydrocarbon whose boiling point may vary from about 45° to about 180° C. Other solvents can also be used, the primary requirement being that they be inert to peracetic acid as well as to glycidol and acetic acid under the conditions employed.", "The solvent should be separable from allyl alcohol and acetic acid by distillation or other reasonable methods.", "The solvent should either be substantially lower boiling than glycidol and easily separable therefrom, or should form an azeotropic mixture with glycidol, or be higher boiling than glycidol if non-azeotropic.", "Solvents forming azeotropes with glycidol are of particular value.", "Various solvents meet these requirements, for example, acetone, ethyl acetate, o-xylene, pseudocumene, monochlorobenzene, ortho-dichlorobenzene, diisobutyl ketone, butyl butyrate, methyl ethyl ketone, isopropyl acetate, methylal, dioxane and halogenated solvents containing not more than six carbon atoms such as chloroform, carbon tetrachloride, perchloroethylene, and fluorinated alkanes.", "Particularly preferred solvents are acetone, pseudocumene and diisobutyl ketone.", "Generally, the peracetic acid content of the solution is between 5 and 40%, this upper limit being a consequence of the explosion hazard associated with too highly concentrated peracetic acid.", "Peracetic acid concentrations below 5% can be used, however, such dilutions are unattractive in a commercial operation.", "As a consequence of its preparation the peracetic solution will usually contain a small amount of acetic acid, e.g., 5 to 10% is a common tolerable amount.", "The rate at which the allyl alcohol is epoxidized increases with increasing temperatures.", "For best operation of the process temperature may be between about 25° and 100° C., and is preferably between about 40° and 65° C. Although elevated pressures can be employed to make possible operation at temperatures above the normal boiling point of the system, no overall advantage follows as the reaction is preferably conducted at atmospheric pressure.", "Variation of the reaction rate with temperature is illustrated by the 40 hours required for completion of the reaction at room temperature, as compared with completion in a period between 21/2 to 4 hours at 60° C., when the process is operated as a batch process.", "We have found that the reaction rate decreases sharply as the percent conversion of the minor reactant increases to a level above 75%, and particularly above 85%.", "The reaction carried out at 45° C., using 3:1 molar ratio of allyl alcohol to peracetic acid, results in 90% peracetic acid conversion in 3.5 hours.", "After 5 hours the conversion is about 93%.", "In most cases nearly quantitative yields of glycidol based on allyl alcohol are obtained.", "Due to these diminishing reaction rates, it is preferable to terminate the epoxidation reaction at some point prior to exhaustion of either of the reactants and to further epoxidize in a second stage.", "We have found that residual peracetic acid and allyl alcohol further react in the glycidol separation unit.", "This is utilized advantageously to accomplish a second stage epoxidation in the glycidol separation unit, and, in effect, combine this operation with the glycidol purification.", "Although the percentage conversion to which the epoxidation reaction is carried in the first stage varies depending upon the reaction conditions and equipment utilized, it is preferred that it should be within the range of between about 70 and 95% of the minor reactant.", "Various process options are available.", "The process, for example, may be operated using a low boiling solvent with no diluent, a low boiling solvent with the addition of another solvent which acts as a diluent, or a high boiling solvent alone.", "The process for the preparation of glycerol using a low boiling solvent is described with reference to FIG. 1. Allyl alcohol is fed through line 1 to reactor 21.", "Peracetic acid at 5 to 40% and preferably 15-25% weight concentration in a substantially anhydrous, inert, solvent, such as ethyl acetate or acetone, is fed through line 2 to reactor 21, where the reaction mixture is maintained at a temperature between 35° and 70° C. The peracetic acid solution usually contains 5-10% of acetic acid.", "The crude mixture of reaction products containing glycidol is drawn through line 3 and fed to distillation column 22 which is maintained at reduced pressure.", "The organic solvent is vaporized and removed through line 4.", "In the column we prefer, when using acetone as the solvent, to maintain the vapor temperatures at about 24° C., the bottom of column 22 operating at 170 mm.", "of Hg.", "will be at a temperature of about 80° C. with an underflow composed of acetic acid, glycidol and a small amount of the solvent.", "This mixture is withdrawn through line 5 and fed rapidly and continuously to column 23 operating at a low overhead pressure, e.g., about 17mm.", "of Hg.", "Acetic acid and unreacted allyl alcohol are removed through line 6 at a vapor temperature of about 29° C. The lower section of the column operating at about 65° C. collects high boiling materials (acetins, glycidol polymerization products, etc.) which are removed as an underflow through line 8 and product glycidol is removed at an intermediate stage through line 7 and condensed in condenser 24.", "When glycidol is removed through line 7 the reboiler temperature is above 120° C. Reaction between glycidol and acetic acid is minimized by operating so that once the solvent is removed in column 22 the products acetic acid and glycidol are rapidly and continuously separated at as low a temperature as is practicable.", "The glycidol may also be removed through line 8 as an impure product, with a reboiler temperature of 65° to 90° C. In this case it can be purified in a second distillation column, not illustrated, placed between column 23 and condenser 24.", "The product glycidol is then fed through line 9 to a hydrolyzer 25, where water is supplied through line 11, and temperature is maintained at about 100° C. A 10 to 20% solution of glycerol in water is drawn off through line 10 and fed to a concentrator, 26.", "Water from the concentrator 26 is recycled to hydrolyzer 25 through lines 12, and 11.", "Glycerol containing 1 to 2% water is taken from evaporator 26 through line 13 and fed to column 27 operating at 5 mm.", "Hg.", ", where light impurities are taken from the head through line 14.", "Pure glycerol is removed as a vapor through line 15.", "The process for the preparation of glycerol or glycidol using a low boiling solvent and diluent is described with reference to FIG. 2. Allyl alcohol is fed through line 59 to reactor 30.", "Peracetic acid at 5 to 40% and preferably 15 to 25% weight concentration in substantially anhydrous, inert, solvent, such as ethyl acetate or acetone, is fed through line 58 to reactor 30, where the reaction mixture is maintained at a temperature between 35° and 70° C. The peracetic acid solution usually contains 5-10% peracetic acid.", "The diluent, such as xylenes, monochlorobenzene, ethylbenzene, pseudocumene or diisobutyl ketone, is introduced with or near the epoxidation feed to column 32.", "The diluent is preferably added through line 57 to the feed line 51 just prior to the entry of the feed line into column 32 which is maintained at reduced pressure.", "The organic solvent is vaporized and removed through line 59.", "When acetone is used as the solvent, column 32 is operated at an overhead pressure of about 130mm.", "Hg.", "The low boiling solvent such as acetone, passes overhead and the underflow, also containing the diluent, is then fed through line 52 to column 34 from which allyl alcohol, acetic acid and traces of peracetic acid are taken overhead.", "Pressure at the top of the column is maintained at about 50 mm.", "of Hg.", ", the temperature of the overhead vapor at about 50° C. and the reboiler at about 90° C. Some diluent may go overhead with the allyl alcohol, acetic acid and traces of peracetic acid.", "Reaction between glycidol and acetic acid is substantially prevented by the fact that in column 34 the products acetic acid and glycidol are rapidly and continuously separated.", "Glycidol and diluent are withdrawn from the lower portion of column 34 and fed to column 36.", "Many diluents, such as pseudocumene, form an azeotropic mixture with glycidol so that an azeotropic composition can be removed overhead from column 36.", "This actually constitutes an advantage since the amount of diluent used is well in excess of that required to satisfy the azeotrope, so that complete removal of glycidol from the column underflow of column 36 is insured by operating so that a small excess of diluent over the azetropic requirement is removed with the glycidol.", "The glycidol-azeotrope leaves through line 55 and goes to the recovery unit.", "The underflow from column 36 flows through line 56 to column 38 where the diluent is removed overhead through line 60 and returned to the process.", "High boilers are removed as an underflow from column 38.", "The glycidol-diluent azeotrope recovered from column 36 through line 55 may be treated in several ways.", "Pure glycidol can be separated by breaking the azeotrope and separating glycidol for use as a chemical intermediate.", "The azeotropic mixture can be subjected directly to hydrolysis conditions if the solvent selected is stable under the conditions of hydrolysis employed and separable from the hydroysate.", "Hydrolysis of the azeotropic mixture proceeds readily;", "the glycerol partitions into the aqueous phase so that the diluent can be decanted off for recycle to the system leaving the aqueous phase to be concentrated and the glycerol subsequently refined.", "The process employing a high boiling solvent and no diluent is described with reference to FIG. 3. Allyl alcohol is fed to reactor 40 through line 88.", "Peracetic acid at 5 to 40% weight concentration in an inert high boiling solvent such as diisobutyl ketone, is fed through line 87 to reactor 40 where the reaction mixture is maintained at a temperature between 35° and 70° C. The peracetic acid solution usually contains 5 to 10% acetic acid.", "An excess of alcohol is preferred.", "The epoxidation reaction is carried to substantially complete conversion of the minor reactant, and the mixture is then fed from the epoxidizer through line 81 to column 42 wherein acetic acid, surviving peracetic acid and allyl alcohol are removed overhead.", "This column is kept operating at an overhead pressure of about 40 mm.", "of Hg.", ", a feed plate temperature of about 75° C. and reboiler temperature of about 92° C. when using diisobutyl ketone as the solvent.", "The glycidol-high boiling solvent solution is removed from column 42 as an underflow through line 82 and fed to column 44.", "Reaction between glycidol and acetic acid is largely prevented by the fact that in column 42 the products acetic acid and glycidol are rapidly and continuously separated.", "In column 44, when using diisobutyl ketone as the solvent, the column is operated with an overhead pressure of about 50 mm.", "of Hg.", "and a vapor temperature of about 78° C. when the reboiler is operated at about 88° to 92° C. Glycidol is removed as a vapor through line 85.", "When diisobutyl ketone is used as the solvent, the glycidol is obtained in the form of the azeotrope with diisobutyl ketone.", "The glycidol-solvent mixture may be fed directly to the hydrolyzer along with the requisite amount of water, and the mixture held at reaction temperature until hydrolysis is complete.", "The mixture is then cooled and, when diisobutyl ketone is used as the solvent, the solvent is decanted from the aqueous glycerol mixture and returned to the process.", "The glycerol is concentrated and refined by conventional methods.", "The glycidol-solvent mixture leaving column 44 through line 85 can, if desired, be processed to recover product glycidol.", "The underflow from column 44 containing solvent leaves through line 83 and is fed to column 46.", "Column 46 is operated to separate the solvent, which is returned to the process, from high boilers which leave the process through line 89.", "The processes of this invention are further illustrated in the following examples which are given by way of example and not by way of limitation to illustrate the invention to those skilled in the art.", "All parts and percentages are by weight unless otherwise specified.", "EXAMPLE 1 The equipment consisted of a 12-liter resin flask fitted with an aluminum cooling coil, containing a seven-neck head equipped with a condenser, mechanical stirrer, thermometer, two addition funnels, and the inlet and outlet for the cooling coil.", "The charge consisted of about 12 moles of peracetic acid as a 15-30% solution in acetone containing 6-8% acetic acid and the appropriate quantity of allyl alcohol, as shown in the table.", "The peracetic acid and allyl alcohol were added to the reactor simultaneously through the addition funnels over a period of 39 minutes.", "The reactant ratios, temperatures, reaction time, allyl alcohol conversions, and glycidol yields (based on allyl alcohol) are given in the following table: ______________________________________Moles allyl Peracetic Allyl alco- Glycidolalcohol per Time, Conc.", "Temp.", "hol conver- Yield,mole peracid hours % ° C. sion, % %______________________________________A 0.77 2.0 19.8 69 92.7 94.5B 1.3 3.0 20.3 55 65.1 95.8C 1.3 4.0 15.0 55 64.2 92.6D 2.0 6.0 20.0 45 45.9 100.", "E 3.0 3.75 30.0 55 31.8 100.", "______________________________________ F. 346 parts of a solution obtained from A of this example were fed at 3.5 milliliters per minute to the mid-point of a rectification column operated at 100 millimeters Hg.", "pressure.", "The actone was taken off overhead and contained less than 1 percent acetic acid and no glycidol.", "The underflow from the column contained 98% of the glycidol fed to the column.", "This crude glycidol was then fed to a column operated at 29 millimeters Hg.", "Acetic acid was removed overhead together with unconverted allyl alcohol.", "The high boiling components were withdrawn from the bottom, and at a level one plate above the reboiler section a vapor was withdrawn and condensed to give glycidol containing one percent acetic acid, representing 98.5% of the glycidol in the feed.", "G. A mixture of 432 parts of water, one part of 90% formic acid and 72 parts of glycidol obtained from operation "F"", "of this example was heated at 60° C. for 4 hours at which time all the glycidol had been consumed.", "Water was then removed by evaporation and the glycerol was distilled through a short column at 15 millimeters Hg.", "The fraction distilling over the range of 167°-172° C. consisted of 86 parts and represented a 96% yield of glycerol based on the glycidol charged.", "The product obtained in this manner meets commercial specifications.", "Similar results are obtained using this procedure by substituting for acetone: ethyl acetate, methylal, benzene and chloroform.", "EXAMPLE 2 An epoxidation vessel was charged with allyl alcohol (2668 g., 99.1 percent assay, 45.52 moles) which was heated to 45° C. To this was added a solution of peracetic acid in acetone (5390 g. of 21.4 percent peracetic acid, 15.18 moles) during 10 minutes while cooling to maintain a temperature of 45° C. The mixture was then held at 45° C and sampled at intervals to determine the conversion of peracetic acid.", "After approximately 3 hours, the peracetic acid conversion was 93.9 percent;", "13.71 moles of allyl alcohol had been consumed and 13.01 moles of glycidol appeared for an alcohol reaction efficiency of 94.9 percent.", "The mixture was held for an additional hour at 45° C., then rapidly cooled to 12° C. The epoxidation mixture (7444 g.) was diluted with pseudocumene (3722 g.) and the mixture was fed, at a rate of 62.1 g/minute to a 2-inch Oldershaw distillation column, constituted in descending order as follows: refrigerated condenser, magnetic reflux head, 10-tray section, feed section, 5-tray section, temperature sensor, reboiler.", "Feed composition was as follows: ______________________________________Component Weight percent______________________________________Acetone 33.3Allyl alcohol 14.8Acetic acid 9.77Glycidol 8.09High boilers 0.67Pseudocumene 33.3______________________________________ Pressure at the top of the column was 75 mm.", "Hg.", "column temperatures were: overhead vapor, 6°-6.5° C.;", "feed plate, 32°-33.5° C.;", "reboiler, 61.5°-62.5° C. The reflux ratio was 1:1.", "From a total feed of 11.166 g., there were obtained 3,664 g. of distillate and 7.502 g. of underflow of the following weight percent compositions: ______________________________________Component Distillate, 3.664 g. Underflow, 7.502 g.______________________________________Acetone 98.1 0.8Allyl alcohol 0.8 21.6Acetic Acid 0.02 14.45Glycidol 0.1 11.84Pseudocumene -- 50.3Unidentified 1.0 --High boilers -- 1.0______________________________________ Recovery of glycidol was 98.3 percent.", "The underflow (7,473 g.) from the acetone removal column was fed at a rate of 40 g./minute to a 2-inch Oldershaw column constituted as follows: water-cooled condenser, magnetic reflux head, 10-tray section, temperature sensor, 10-tray section, feed section, 25 tray section, reboiler.", "Pressure at the top of the column ws 50 mm.", "of Hg.", "reflux ratio was 1:1.", "Column temperatures were: overhead vapor, 47.5° C.;", "10th tray 51.5° C.;", "feed tray 60° C;", "reboiler 90° C. Column effluent weight percent compositions were as follows: ______________________________________Component Distillate (2,768 g.) Underflow (4,802 g.)______________________________________Acetic acid 34.78 1.27Glycidol 0.15 18.28Pseudocumene 4.4 78.8High boilers -- 1.6Allyl Alcohol 58.31 --Acetone 2.17 --______________________________________ Recovery of glycidol across this column was 99.2 percent.", "Recovery of glycidol azeotrope from the underflow of the acetic acid removal column was achieved by feeding the underflow to a 1 -inch Oldershaw column constituted in descending order as follows: water-cooled condenser, magnetic reflux head (set at 1:1), 5-trays, feed section, 5-trays, reboiler.", "At a column head pressure of 60 mm.", ", the vapor temperature was 75.5° C., the reboiler temperature was 89° C. From 4,160 g. of feed, there were obtained 2,082 g. of distillate containing 33.0 percent glycidol and 2,050 g. of underflow containing 2.56 percent glycidol.", "EXAMPLE 3 Epoxidation was conducted by reacting allyl alcohol with 15 percent peracetic acid in acetone at a ratio of 1.3 moles allyl alcohol/mole of peracetic acid.", "Peracetic acid conversion was carried to 90 percent.", "The reaction mixture was then diluted with pseudocumene to give a mixture which was fed to an acetone removal column.", "In the following discussion, each component rate through the system is shown in pounds per hour.", "The column consisted of: water-cooled condenser, reflux head (1:1 reflux), 10-trays, feed section, 10-trays, reboiler.", "Overhead pressure was 400 mm.", "Hg.", ", temperature 40° C.;", "reboiler pressure was 415 mm.", "Hg.", ", temperature 109° C. Feed composition (lb/hr.) was: acetone, 24.13;", "allyl alcohol, 1,382;", "peracetic acid, 0.452;", "acetic acid, 4.722;", "glycidol, 3.767;", "high boilers, 0.200;", "pseudocumene, 30.13.", "Overhead was taken: acetone, 24.08;", "allyl alcohol, 0.121.", "The underflow consisted of: acetone, 0.042;", "allyl alcohol, 0.915;", "peracetic acid, nil;", "acetic acid, 5.080;", "glycidol, 4.169;", "high boilers, 0.243;", "pseudocumene, 30.13.", "The underflow from the acetone removal column was fed to the acetic acid removal column, consisting of: water-cooled condenser, reflux head (2:1 reflux ratio), 30-trays, feed section, 20-trays, reboiler.", "Overhead pressure was 50 mm.", "Hg.", ", temperature 46.5° C.;", "reboiler pressure was 88 mm.", "Hg.", ", temperature, 90° C. Overhead was taken: acetone, 0.042;", "allyl alcohol, 0.915;", "acetic acid, 5.011;", "glycidol, 0.0065;", "pseudocumene, 0.314.", "The underflow consisted of: acetic acid, 0.0684;", "glycidol, 4.15;", "high boilers, 0.255;", "pseudocumene, 29.82.", "The underflow from the acetic acid removal column was fed to the glycidol azeotrope column which consisted of: water-cooled condenser, reflux head (2:1 reflux ratio), 5-trays, feed section, 10-trays.", "Overhead pressure was 60 mm.", "Hg.", ", temperature, 80° C.;", "reboiler pressure was 70 mm.", "Hg.", ", temperature 93° C. Overhead was taken: acetic acid, 0.0684;", "glycidol, 4.150;", "pseudocumene, 8.428.", "The underflow consisted of high boilers, 0.255;", "pseudocumene, 21.39.", "Pseudocumene was recovered from the underflow for recycle by simple distillation.", "EXAMPLE 4 A solution of peracetic acid, 7.70 percent (32.1 moles), and acetic acid, 3.55 percent (20.6 moles) in diisobutyl ketone was treated with allyl alcohol (41.7 moles) at 50° C. for 2.5 hours, then held at 57° -58° C. for another 3 hours.", "At the end of this time, the conversion of peracetic acid was 94.0 percent with an indicated reaction efficiency to glycidol of 92.4 percent based on allyl alcohol and 86.2 percent based on peracetic acid.", "The epoxidation mixture was fed at a rate of 35.8 g./min.", "to a 2-inch Oldershaw column constituted as follows: water-cooled condenser, reflux head (6:1 reflux ratio), 10-trays, temperature sensor, 10-trays, feed section, 30-trays, reboiler.", "Overhead pressure was 38 mm.", "Hg.", ", temperature, 35.5° -36.0° C. Feed-plate temperature was 74° C., reboiler temperature, 91.5° -92° C. Approximately 12.5 percent of the feed was taken overhead and contained the following: allyl alcohol, 13.46 moles;", "acetic acid, 50.55 moles, corresponding to an efficiency of 94.9 percent based on total acids charged to the epoxidation.", "The underflow from the acetic acid removal column, containing 0.14 percent acetic acid, was fed at 44 g./min.", "to the glycidol azeotrope column which consisted of a 2-inch Oldershaw, arranged as follows: water-cooled condenser, reflux head (2:1 reflux ratio), 5-trays, feed section, 10-trays, reboiler.", "Overhead pressure was 50 mm..", "Hg.", "and the vapor temperature was 77.5° -78° C. The reboiler operated at 89° -91° C. Approximately 28.5 percent of the feed was taken overhead, and contained 29.9 percent glycidol (corresponding to 25.03 moles), 0.48 percent acetic acid.", "Only 0.03 percent glycidol was contained in the underflow.", "The recovery of glycidol corresponds to an efficiency of 88.7 percent based on unrecovered allyl alcohol.", "The underflow from the glycidol azeotrope column was flash distilled to recover the diisobutyl ketone for recycle.", "EXAMPLE 5 An agitated reaction vessel was charged with 9,125 g. of water which was heated to reflux.", "To this was added at a rate of 50 ml.", "/min.", "3,050 g. of a solution of glycidol (29.92%, 912.5 g., 12.33 moles) and acetic acid (0.35%, 10.7 g., 0.178 mole) in diisobutyl ketone which had been obtaind by azeotropic distillation.", "After completion of the glycidol addition, the mixture was held under reflux for another 3 hours.", "After cooling, the diisobutyl ketone layer which separated was decanted from the aqueous glycerol and recycled to the process.", "The glycerol content of the aqueous hydrolysate was 10.9 percent corresponding to a crude yield of 96 percent.", "The pH of the solution was adjusted by the addition of 0.2 mole of sodium hydroxide, and the solution was concentrated to give 1,172 g. of crude glycerol.", "This was distilled at reduced pressure to give refined glycerol meeting commercial specifications.", "As will be apparent to those skilled in the art, numerous modifications and variations of the embodiments illustrated above may be made without departing from the spirit of the invention or the scope of the following claims." ]
FIELD OF THE INVENTION The present invention relates to a tool and in particular to a tool which is portable or employed as a robotic end effector for installaing nutplates onto a structural part. BACKGROUND OF THE INVENTION Nutplates are extensively used in, for example, aircraft. They serve as anchoring devices and require several manual and power tool operations to install. For example, the installation of nutplates is required on the fixed leading edges of both the 757 and 767 model commercial aircraft being manufactured by the Boeing company. Each model presently requires approximately 1000 nutplates per wing ship set. Various steps are involved in installing a nutplate, and these are quite labor intensive. These steps, described with reference to FIG. 1, involve the following operations: (1) a pilot hole 1 is drilled in the structural part 2; (2) two rivet holes 3 are drilled adjacent to the pilot hole and countersunk; (3) the pilot hole is opened up to final screw hole size; (4) all three holes are deburred by hand; (5) rivets 4 are inserted by hand in a one by one fashion into the rivet holes; (6) a holding screw (not shown) is placed in the center screw hole, the nutplate 5 is positioned over the rivets which were installed during step (5) and the holding screw is then tightened; (7) the rivets are swaged one by one; and (8) the holding screw is removed completing the installation. It is readily apparent that when this eight step procedure is repeated for the 1000 nutplates per wing ship set as noted above, a considerable investment in manhours is required. Any measure which would reduce the total steps required to install the nutplates would be useful. SUMMARY OF THE INVENTION According to the present invention a unique tool is introduced which will perform the following operations sequentially and automatically: rivet feed and rivet insertion; nutplate feed and nutplate positioning; rivet squeezing. In effect, steps (5)-(8) noted above are replaced in that they are performed sequentially and automatically by the tool of the present invention. As a result a considerable savings in manhours is realized. The tool is preferably a portable, hand held tool, or useable with a robot. It contains a supply of nutplates and access to a supply of rivets. These are dispensed from the tool in an automatically controlled manner and the nutplate finally assembled. While the invention was developed for installing nutplates, it can be used for installing other types of fasteners or support elements which are mounted with rivets. It would be necessary to adapt the supply mechanism of the tool to accommodate the particular size and shape of the fasteners or support elements to be dispensed. BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schemactic perspective view of a structural part and a nutplate assembly, referred to above in the background discussion for the purpose of better understanding one application of the invention. Six figures have been selected to illustrate a preferred embodiment of the invention. Included are: FIG. 2, which is a partial perspective view of a preferred embodiment of the tool assembly of the present invention. FIG. 3, which is a front elevational view of the tool of FIG. 2 without the nutplate magazines; FIG. 4, which is a top view of the tool of FIGS. 1 and 2; FIG. 5, which is front elevational view of a nutplate magazine; and FIG. 6, which is a side view partly in section taken along line 6--6 of FIG. 4. DESCRIPTION OF THE PREFERRED EMBODIMENT In its preferred form the tool assembly 10 is portable and at present weights approximately 12 lbs., excluding its connecting tubes. Referring to FIG. 2, the tool assembly 10 includes a housing 12, a pair of handles 14, two nutplate magazines 16, a rivet feed and insertion mechanism 18, a pick-up and transfer mechanism 20, a clamping assembly 22 and a switch block 24 including certain manually operable switches to control the operation of the tool. The housing 12 comprises, in essence, a series of connected plates: two top plates 26 and 28, four side plates, 30 and 32 (two on each side), and a bottom plate 34. These plates are joined together by a series of socket screws 36 (shown best in FIG. 3). The side plates 30 and 32, on both sides, include bosses 38 which receive socket screws 40 for mounting the bottom handle plates 41 and top handle plates 42 to the assembled housing. The left-side top plate 42 (FIG. 3) also serves to mount the rivet feed and insertion mechanism 18 to the assembled housing, and the right-side top plate 42 also serves to mount the switch block 24 to the assembled housing. The handles 14 are connected to their bottom and top plates 41 and 42 by socket screws 44. The left-hand handle 14 (FIG. 3) also provides a mounting for a push-button switch 46, the purpose of which will be described hereinafter. The left-side side plates 30 are provided with ledges 48 which are coplanar and extend toward each other (FIG. 2) and serve to mount a rotary actuator 50, the purpose of which will be described hereinafter. The top plate 26 has a magnet 52 and a bucking bar 54 mounted thereto. The bucking bar 54 has a post 56 mounted thereto by a socket screw 58. The post 56 serves as an alignment post. Mounted within the housing to the left of center is a hydraulic cylinder assembly 60, which operates in conjunction with the pick-up assembly. Further details of the hydraulic cylinder assembly 60 can be seen in FIG. 6 and will be described in more detail hereinafter. Mounted within the housing to the right of center is a hydraulic cylinder assembly 62 which operates in conjunction with the clamping assembly 22. In approximately the center of the housing toward the front and rear side plates there is mounted a hydraulic cylinder 64 which operates in conjunction with a nutplate retaining assembly 66. The nutplate magazines 16 (FIG. 5) include a pair of plates 68 joined together by four socket screws 70. When joined, the plates 68 define a chamber 72. A piston 74 divides the chamber 72 into a nutplate loading chamber 72a and a pneumatic chamber 72b. A tube fitting 76 admits pressurized air to the pneumatic chamber 72b. A guide rod 78 is connected to the piston 74 on both sides thereof. The guide piston rod 78 serves to stack and align the nutplates in the loading chamber 72b thereby guiding them out of the loading chamber 72a as they are being dispensed. The nutplate magazines 16 are received within recesses 80 defined by the side plates 30 and 32 and are retained in assembly with the housing by ball plungers 82 each including spring loaded balls 84. For this purpose each nutplate magazine has a corresponding ball button 86 which has a recess 88 within which a corresponding ball 84 is received for locking the nutplate magazines in assembly. The ball buttons 86 are secured to the sides of the nutplate magazine by socket screws 90. With the noted design, the nutplate magazines are snapped-into assembly with the housing and positively retained (locked) in assembly by the engagement of the balls 84 with their respective recesses 88. The nutplate magazines are easily withdrawn from the noted positive retention after first releasing them from their engagement with their respective nutplate retaining assembly by simply prying them out or by a specially designed tool which is inserted in the cut-out portions 92, formed by the plates 30 and 32, for gripping the side surfaces of the magazine and disengaging the balls 84 from their respective recesses 88. As shown in FIG. 4, at the top of each recess 80 there is situated a nutplate retaining assembly 66 which includes a T-piece 94 attached to a hydraulic cylinder assembly 60. Mounted in turn to the T-piece 94 are spaced apart retaining clip mounts 96 which are mounted by pins 98. Extending outwardly from each retaining clip mount 96 is a retaining clip 100. The retaining clips 100 are biased toward each other by a spring 102. Each retaining clip mount 96 is pivotably mounted by a pivot pin 104 to the top plates 26 and 28 (FIG. 3), i.e., the left-hand retaining clip mount is pivotably mounted to the top plate 26 and the right-hand retaining clip mount is pivotably mounted to the top plate 28. Movement of the T-piece 94 upwardly causes the retaining clip mounts 96 to pivot upwardly about their pins 104 thereby pivoting upwardly the retaining clips 100. When pivoted upwardly, the nutplate magazine can be withdrawn from the housing as noted above. In the retained position, the nutplate is ready to be picked-up by the pick-up plate 106 of the pick-up assembly 20 for transfer toward the bucking bar 54. For this purpose, the front end of each retaining clip 100 has a truncated conical shape which permits the pick-up plate 106 to engage the truncated front ends and move the retaining clips 100 against their spring biasing force sufficiently to permit release of a nutplate into the pick-up plate. The rivet supply and insertion mechanism 18 includes a rivet block 108 which is fastened to the left-side top plate 42 by socket screws 110. Two rivet supply tubes 112 are connected to the rivet block 108. Formed in the rivet block 108 are two parallel rivet passages 114 which are connected to a respective rivet tube holder 116 forming thereby an extension of the supply tubes 112. Mounted to the rivet block 108 is a pneumatic actuator 118 for each passage 114. The actuators 118 include a front end stop (not shown) which is actuated to extend into its respective passage 114 and act as a rivet stop. Connected to the back end of each actuator is an air supply tube (not shown). The passages 114 terminate in an upper flange 120 which includes two openings 122 through which the rivets exit and are supplied to the rivet holes 3 of the structural part 2. The upper flange also includes a post 124 mounted thereto by a socket screw 126. The post 124 serves as an alignment post. The switch block 24 is secured to the right-side top plate 42 by socket screws 128. The switch block 24 houses push button switchs 130, 132, 134, 136, and 138. These switches, as well as switch 46 and toggle switch 140, are connected to a controller (not shown) which controls a program sequence for operating the tool. The switches 130 and 136 each independently set the program and the tool functioning through the first two separate installation steps, i.e., steps (5) and (6) noted above, except that the rivets are inserted by the tool and the nutplate positioned over the rivets by the tool and without a holding screw. The switches 134 and 46 control the clamping operation, i.e., the last two separate installation steps (7) and (8) noted above except that a holding screw is not utilized. In effect, therefore, the last two steps are in fact a single step according to which the rivet tails are swaged (clamped) by the tool. The switches 132 and 138 are repeat switches which allow the operator to repeat the first or second installation step if necessary. The toggle switch 140 operates in conjunction with the lights 142 and 144 and controls the swing approach mode of the pick-up plate 106 to swing either right or left between the nutplate magazines 16 (front or back) and the bucking bar 54. The light 142 or 144 is lit depending on whether the pick-up plate 106 swings right or left. The lights inform the operator as to the set mode of operation of the pick-up plate. In its neutral position, the toggle switch 140 causes the hydraulic cylinder assemblus 60 to lift their respective T-piece 94 allowing the associate nutplate magazines to be withdrawn from the housing. The toggle switch 140 along with the switches 132 and 138 operate to change the swing approach from right to left or from left to right. In the manual operation, the operator grasps handles 14 and places upper flange 120 flush against the structural part with post 124 in pilot hole 1, thereby aligning opening 122 with the rivet holes 3 on each side of the pilot hole 1. The operator then depresses switch 130 or 136 causing a rivet to be fed from a rivet supply and inserted into rivet holes 3. The operator then removes the upper flange 120 from the structural part and places bucking bar 54 flush against the structural part with the post 56 in pilot hole 1. Next the operator again depresses switch 130 or 136 causing the pick-up plate 106 to pick-up a nutplate from one of the nutplate magazines, swing over to the bucking bar 54 and drop the nutplate over the rivets and post 56. The operator then depresses switches 134 and 46 and causes the forked clamping arm 146 of the clamping assembly 22 to swage the exposed tails of the two rivets thereby retaining the dropped nutplate into assembly with the swaged rivets on the structural part. The switches 130 and 136 and 132 and 138 are duplicate function switches. That is, the operator chooses one set or the other depending on whether the structural part has a right-hand or left-hand flange on which the nutplates are being installed. The rivet supply may be the feeder bowl arrangement similar to that supplied by ITC Automation, Inc,, of Dayton, Ohio. The various mechanisms for controlling the operation of the pick-up and transfer mechanism 20 and the clamping assembly 22 are shown in FIG. 6. The rotary actuator 50 has a no-slip pulley 148 mounted to a shaft 150. The pulley 148 is connected to a no-slip pulley 152 by a no-slip positive drive belt 154. The pulley 152 is in turn mounted to a sleeve 156 which is fastened to a super ball push bearing 158 by a lock set screw 160. The sleeve 156 and bearing 158 extend between thrust bearings 162 and 164. Between the bearing 164 and the top plate 26 there is located a spring 166 which surrounds a ball-groove shaft 168, to the top of which the pick-up plate 106 is mounted by a socket screw 170. The bearing 162 rests on a bridge 172 which extends from side plates 30, as do the ledges 48 (not shown in FIG. 6). At the bridge 172, the shaft 168 is surrounded by a bushing 174. At its opposite end the shaft 168 has a lift washer 176 mounted thereto by a socket screw 178. The lift washer 176 has a flange 180 which is received within a slot 182 of a lift arm 184 connected to the cylinder assembly 60. A locating pin 186 engages the lift arm 184. For the installation of a nutplate, the tool is brought to the structural part and aligned as noted above. The magnet 52 holds the structural part against the bucking bar 54, and the switching sequence noted above initiated. The cylinder 60 and actuator 50 are energized which causes the shaft 168 to first be rotated to either nutplate magazine, lowered to pick-up a nutplate, raised and rotated again to the position shown in FIG. 6. At this time the nutplate is released as noted above. For this purpose, a cylinder 188 mounted in the pick-up plate 106 releases a clamp 190 which was holding the nutplate. Once the nutplate is installed, the clamping arm 146 is lowered as noted above. For this purpose the arm 146 is mounted to a shaft 192 by a socket screw 194. With the nutplate tool described above significant saves in manhours for installing nutplates can be realized.
A tool for installing nutplates to a structural part. The tool is portable or useable with a robot. The tool includes a supply of nutplates and a rivet feeding and insertion mechanism. The rivets are inserted in the structural part, followed by the positioning of a nutplate into engagement with the rivets and finally by clamping of the rivets to retain the nutplate in assembly with the clamped rivets.
Condense the core contents of the given document.
[ "FIELD OF THE INVENTION The present invention relates to a tool and in particular to a tool which is portable or employed as a robotic end effector for installaing nutplates onto a structural part.", "BACKGROUND OF THE INVENTION Nutplates are extensively used in, for example, aircraft.", "They serve as anchoring devices and require several manual and power tool operations to install.", "For example, the installation of nutplates is required on the fixed leading edges of both the 757 and 767 model commercial aircraft being manufactured by the Boeing company.", "Each model presently requires approximately 1000 nutplates per wing ship set.", "Various steps are involved in installing a nutplate, and these are quite labor intensive.", "These steps, described with reference to FIG. 1, involve the following operations: (1) a pilot hole 1 is drilled in the structural part 2;", "(2) two rivet holes 3 are drilled adjacent to the pilot hole and countersunk;", "(3) the pilot hole is opened up to final screw hole size;", "(4) all three holes are deburred by hand;", "(5) rivets 4 are inserted by hand in a one by one fashion into the rivet holes;", "(6) a holding screw (not shown) is placed in the center screw hole, the nutplate 5 is positioned over the rivets which were installed during step (5) and the holding screw is then tightened;", "(7) the rivets are swaged one by one;", "and (8) the holding screw is removed completing the installation.", "It is readily apparent that when this eight step procedure is repeated for the 1000 nutplates per wing ship set as noted above, a considerable investment in manhours is required.", "Any measure which would reduce the total steps required to install the nutplates would be useful.", "SUMMARY OF THE INVENTION According to the present invention a unique tool is introduced which will perform the following operations sequentially and automatically: rivet feed and rivet insertion;", "nutplate feed and nutplate positioning;", "rivet squeezing.", "In effect, steps (5)-(8) noted above are replaced in that they are performed sequentially and automatically by the tool of the present invention.", "As a result a considerable savings in manhours is realized.", "The tool is preferably a portable, hand held tool, or useable with a robot.", "It contains a supply of nutplates and access to a supply of rivets.", "These are dispensed from the tool in an automatically controlled manner and the nutplate finally assembled.", "While the invention was developed for installing nutplates, it can be used for installing other types of fasteners or support elements which are mounted with rivets.", "It would be necessary to adapt the supply mechanism of the tool to accommodate the particular size and shape of the fasteners or support elements to be dispensed.", "BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schemactic perspective view of a structural part and a nutplate assembly, referred to above in the background discussion for the purpose of better understanding one application of the invention.", "Six figures have been selected to illustrate a preferred embodiment of the invention.", "Included are: FIG. 2, which is a partial perspective view of a preferred embodiment of the tool assembly of the present invention.", "FIG. 3, which is a front elevational view of the tool of FIG. 2 without the nutplate magazines;", "FIG. 4, which is a top view of the tool of FIGS. 1 and 2;", "FIG. 5, which is front elevational view of a nutplate magazine;", "and FIG. 6, which is a side view partly in section taken along line 6--6 of FIG. 4. DESCRIPTION OF THE PREFERRED EMBODIMENT In its preferred form the tool assembly 10 is portable and at present weights approximately 12 lbs.", ", excluding its connecting tubes.", "Referring to FIG. 2, the tool assembly 10 includes a housing 12, a pair of handles 14, two nutplate magazines 16, a rivet feed and insertion mechanism 18, a pick-up and transfer mechanism 20, a clamping assembly 22 and a switch block 24 including certain manually operable switches to control the operation of the tool.", "The housing 12 comprises, in essence, a series of connected plates: two top plates 26 and 28, four side plates, 30 and 32 (two on each side), and a bottom plate 34.", "These plates are joined together by a series of socket screws 36 (shown best in FIG. 3).", "The side plates 30 and 32, on both sides, include bosses 38 which receive socket screws 40 for mounting the bottom handle plates 41 and top handle plates 42 to the assembled housing.", "The left-side top plate 42 (FIG.", "3) also serves to mount the rivet feed and insertion mechanism 18 to the assembled housing, and the right-side top plate 42 also serves to mount the switch block 24 to the assembled housing.", "The handles 14 are connected to their bottom and top plates 41 and 42 by socket screws 44.", "The left-hand handle 14 (FIG.", "3) also provides a mounting for a push-button switch 46, the purpose of which will be described hereinafter.", "The left-side side plates 30 are provided with ledges 48 which are coplanar and extend toward each other (FIG.", "2) and serve to mount a rotary actuator 50, the purpose of which will be described hereinafter.", "The top plate 26 has a magnet 52 and a bucking bar 54 mounted thereto.", "The bucking bar 54 has a post 56 mounted thereto by a socket screw 58.", "The post 56 serves as an alignment post.", "Mounted within the housing to the left of center is a hydraulic cylinder assembly 60, which operates in conjunction with the pick-up assembly.", "Further details of the hydraulic cylinder assembly 60 can be seen in FIG. 6 and will be described in more detail hereinafter.", "Mounted within the housing to the right of center is a hydraulic cylinder assembly 62 which operates in conjunction with the clamping assembly 22.", "In approximately the center of the housing toward the front and rear side plates there is mounted a hydraulic cylinder 64 which operates in conjunction with a nutplate retaining assembly 66.", "The nutplate magazines 16 (FIG.", "5) include a pair of plates 68 joined together by four socket screws 70.", "When joined, the plates 68 define a chamber 72.", "A piston 74 divides the chamber 72 into a nutplate loading chamber 72a and a pneumatic chamber 72b.", "A tube fitting 76 admits pressurized air to the pneumatic chamber 72b.", "A guide rod 78 is connected to the piston 74 on both sides thereof.", "The guide piston rod 78 serves to stack and align the nutplates in the loading chamber 72b thereby guiding them out of the loading chamber 72a as they are being dispensed.", "The nutplate magazines 16 are received within recesses 80 defined by the side plates 30 and 32 and are retained in assembly with the housing by ball plungers 82 each including spring loaded balls 84.", "For this purpose each nutplate magazine has a corresponding ball button 86 which has a recess 88 within which a corresponding ball 84 is received for locking the nutplate magazines in assembly.", "The ball buttons 86 are secured to the sides of the nutplate magazine by socket screws 90.", "With the noted design, the nutplate magazines are snapped-into assembly with the housing and positively retained (locked) in assembly by the engagement of the balls 84 with their respective recesses 88.", "The nutplate magazines are easily withdrawn from the noted positive retention after first releasing them from their engagement with their respective nutplate retaining assembly by simply prying them out or by a specially designed tool which is inserted in the cut-out portions 92, formed by the plates 30 and 32, for gripping the side surfaces of the magazine and disengaging the balls 84 from their respective recesses 88.", "As shown in FIG. 4, at the top of each recess 80 there is situated a nutplate retaining assembly 66 which includes a T-piece 94 attached to a hydraulic cylinder assembly 60.", "Mounted in turn to the T-piece 94 are spaced apart retaining clip mounts 96 which are mounted by pins 98.", "Extending outwardly from each retaining clip mount 96 is a retaining clip 100.", "The retaining clips 100 are biased toward each other by a spring 102.", "Each retaining clip mount 96 is pivotably mounted by a pivot pin 104 to the top plates 26 and 28 (FIG.", "3), i.e., the left-hand retaining clip mount is pivotably mounted to the top plate 26 and the right-hand retaining clip mount is pivotably mounted to the top plate 28.", "Movement of the T-piece 94 upwardly causes the retaining clip mounts 96 to pivot upwardly about their pins 104 thereby pivoting upwardly the retaining clips 100.", "When pivoted upwardly, the nutplate magazine can be withdrawn from the housing as noted above.", "In the retained position, the nutplate is ready to be picked-up by the pick-up plate 106 of the pick-up assembly 20 for transfer toward the bucking bar 54.", "For this purpose, the front end of each retaining clip 100 has a truncated conical shape which permits the pick-up plate 106 to engage the truncated front ends and move the retaining clips 100 against their spring biasing force sufficiently to permit release of a nutplate into the pick-up plate.", "The rivet supply and insertion mechanism 18 includes a rivet block 108 which is fastened to the left-side top plate 42 by socket screws 110.", "Two rivet supply tubes 112 are connected to the rivet block 108.", "Formed in the rivet block 108 are two parallel rivet passages 114 which are connected to a respective rivet tube holder 116 forming thereby an extension of the supply tubes 112.", "Mounted to the rivet block 108 is a pneumatic actuator 118 for each passage 114.", "The actuators 118 include a front end stop (not shown) which is actuated to extend into its respective passage 114 and act as a rivet stop.", "Connected to the back end of each actuator is an air supply tube (not shown).", "The passages 114 terminate in an upper flange 120 which includes two openings 122 through which the rivets exit and are supplied to the rivet holes 3 of the structural part 2.", "The upper flange also includes a post 124 mounted thereto by a socket screw 126.", "The post 124 serves as an alignment post.", "The switch block 24 is secured to the right-side top plate 42 by socket screws 128.", "The switch block 24 houses push button switchs 130, 132, 134, 136, and 138.", "These switches, as well as switch 46 and toggle switch 140, are connected to a controller (not shown) which controls a program sequence for operating the tool.", "The switches 130 and 136 each independently set the program and the tool functioning through the first two separate installation steps, i.e., steps (5) and (6) noted above, except that the rivets are inserted by the tool and the nutplate positioned over the rivets by the tool and without a holding screw.", "The switches 134 and 46 control the clamping operation, i.e., the last two separate installation steps (7) and (8) noted above except that a holding screw is not utilized.", "In effect, therefore, the last two steps are in fact a single step according to which the rivet tails are swaged (clamped) by the tool.", "The switches 132 and 138 are repeat switches which allow the operator to repeat the first or second installation step if necessary.", "The toggle switch 140 operates in conjunction with the lights 142 and 144 and controls the swing approach mode of the pick-up plate 106 to swing either right or left between the nutplate magazines 16 (front or back) and the bucking bar 54.", "The light 142 or 144 is lit depending on whether the pick-up plate 106 swings right or left.", "The lights inform the operator as to the set mode of operation of the pick-up plate.", "In its neutral position, the toggle switch 140 causes the hydraulic cylinder assemblus 60 to lift their respective T-piece 94 allowing the associate nutplate magazines to be withdrawn from the housing.", "The toggle switch 140 along with the switches 132 and 138 operate to change the swing approach from right to left or from left to right.", "In the manual operation, the operator grasps handles 14 and places upper flange 120 flush against the structural part with post 124 in pilot hole 1, thereby aligning opening 122 with the rivet holes 3 on each side of the pilot hole 1.", "The operator then depresses switch 130 or 136 causing a rivet to be fed from a rivet supply and inserted into rivet holes 3.", "The operator then removes the upper flange 120 from the structural part and places bucking bar 54 flush against the structural part with the post 56 in pilot hole 1.", "Next the operator again depresses switch 130 or 136 causing the pick-up plate 106 to pick-up a nutplate from one of the nutplate magazines, swing over to the bucking bar 54 and drop the nutplate over the rivets and post 56.", "The operator then depresses switches 134 and 46 and causes the forked clamping arm 146 of the clamping assembly 22 to swage the exposed tails of the two rivets thereby retaining the dropped nutplate into assembly with the swaged rivets on the structural part.", "The switches 130 and 136 and 132 and 138 are duplicate function switches.", "That is, the operator chooses one set or the other depending on whether the structural part has a right-hand or left-hand flange on which the nutplates are being installed.", "The rivet supply may be the feeder bowl arrangement similar to that supplied by ITC Automation, Inc,, of Dayton, Ohio.", "The various mechanisms for controlling the operation of the pick-up and transfer mechanism 20 and the clamping assembly 22 are shown in FIG. 6. The rotary actuator 50 has a no-slip pulley 148 mounted to a shaft 150.", "The pulley 148 is connected to a no-slip pulley 152 by a no-slip positive drive belt 154.", "The pulley 152 is in turn mounted to a sleeve 156 which is fastened to a super ball push bearing 158 by a lock set screw 160.", "The sleeve 156 and bearing 158 extend between thrust bearings 162 and 164.", "Between the bearing 164 and the top plate 26 there is located a spring 166 which surrounds a ball-groove shaft 168, to the top of which the pick-up plate 106 is mounted by a socket screw 170.", "The bearing 162 rests on a bridge 172 which extends from side plates 30, as do the ledges 48 (not shown in FIG. 6).", "At the bridge 172, the shaft 168 is surrounded by a bushing 174.", "At its opposite end the shaft 168 has a lift washer 176 mounted thereto by a socket screw 178.", "The lift washer 176 has a flange 180 which is received within a slot 182 of a lift arm 184 connected to the cylinder assembly 60.", "A locating pin 186 engages the lift arm 184.", "For the installation of a nutplate, the tool is brought to the structural part and aligned as noted above.", "The magnet 52 holds the structural part against the bucking bar 54, and the switching sequence noted above initiated.", "The cylinder 60 and actuator 50 are energized which causes the shaft 168 to first be rotated to either nutplate magazine, lowered to pick-up a nutplate, raised and rotated again to the position shown in FIG. 6. At this time the nutplate is released as noted above.", "For this purpose, a cylinder 188 mounted in the pick-up plate 106 releases a clamp 190 which was holding the nutplate.", "Once the nutplate is installed, the clamping arm 146 is lowered as noted above.", "For this purpose the arm 146 is mounted to a shaft 192 by a socket screw 194.", "With the nutplate tool described above significant saves in manhours for installing nutplates can be realized." ]
CROSS REFERENCE TO RELATED APPLICATIONS [0001] U.S. patent application Ser. No. ______ Docket Number FIS9-2001-0263, assigned to the assignee hereof and filed concurrently herewith discloses types of lenses useful in the practice of the subject invention and is incorporated by reference herein. FIELD OF THE INVENTION [0002] The field of the invention is multi-beam electron beam lithography. BACKGROUND OF THE INVENTION [0003] It is generally accepted in the mask industry that single beam electron beam mask writers will not be able to deliver the current density at high resolution to achieve exposure speeds required for products below 100 nm GR (Ground Rules). The usable current in probe forming systems is limited by stochastic Coulomb interactions, primarily at apertures or beam crossovers, which translates into loss of resolution. By contrast, multibeam systems suffer much less from this problem since the total current delivered to the target is spread over many beams, in most cases, each with its own apertures and crossovers. [0004] Multibeam systems proposed to date have problems with manufacturing feasibility primarily because of unattainable stability and uniformity requirements placed on the electron sources, i.e. field emitters and photocathodes. Some of these systems employ multibeams through part of the optics column but share the same crossover, which does not improve the electron interaction problem. Their stability requirements are further magnified since they typically use 1 to 1 imaging of the source at the target. [0005] A uniform magnetic field (solenoid field) oriented along the electron beam axis is the simplest of electron lenses and has been employed in various electron beam systems. Electrons radiating from a point object execute, by virtue of their transverse velocity component, one cyclotron orbit in the transverse plane, returning to the optic axis. Thus, an image is formed with unity magnification. A major advantage of the solenoid lens is that there is no prescribed optic axis, hence a shift (deflection) of the beam by a transverse field will cause the beam to shift position, but maintain the same focal plane. A major disadvantage of these lenses is that they produce no demagnification of the object, so that defects in the source (reticle, shaping aperture) are reproduced in the image at the same scale. [0006] The restriction of lenses formed by solenoid fields in the prior art to a one-to-one object to image ratio imposes severe limitations on the image quality. It is well known that the conventional object to image ratio of 4:1 in optical steppers is more “forgiving”, than a 1:1 demagnification ratio. [0007] Such a 1:1 magnification ratio in a multiple-beam system is illustrated in U.S. Pat. Nos. [0008] 6,175,122, 5,981,962 and 5,962,859, which show a plurality of shaped-beam systems, contained within the same solenoid field. In such a system, imperfections in the aperture result in the same imperfections in the image, thus limiting resolution. SUMMARY OF THE INVENTION [0009] The invention relates to a multi-beam lithography system in which a set of electron beam sub-systems having a substantial demagnification are immersed in a solenoid field and operate in parallel. [0010] A feature of the invention is the use of a single solenoid field common to several electron beam sub-systems. [0011] Another feature of the invention is the use of magnetic lenses having substantial demagnification, so that imperfections in the object are reduced in the image by the demagnification factor. BRIEF DESCRIPTION OF THE DRAWINGS [0012] [0012]FIG. 1 shows an embodiment of the invention in cross section. [0013] [0013]FIG. 2 shows a top view of an embodiment of the invention. [0014] [0014]FIG. 3 shows a top view of an alternative embodiment of the invention. [0015] [0015]FIGS. 4A, 4B and 4 C show a cross section of a portion of the invention, an associated beam trace and an associated plot of field strength. [0016] FIGS. 5 A, and 5 B show a cross section of another embodiment of the invention and an associated plot of field strength. DESCRIPTION OF THE PREFERRED EMBODIMENT [0017] Referring now to FIG. 1, there is shown in cross section an embodiment of the invention having three independently controlled variable shape electron beams apparatus immersed in a common solenoid field. These subsystems (subsystems in the overall multi-beam system) are positioned in close proximity (on the order of 20 mm center-to-center) and simultaneously expose an array of stitched subfields that together expose the full field pattern, illustratively an integrated circuit. The imaging system employs high demagnification of the object, thus suppressing flaws in the source (i.e. the surface of a shaping aperture). [0018] The overall solenoid magnetic field is provided by coils 12 - 1 , 12 - 2 and 12 - 3 in sections 100 , 200 and 300 , respectively. A capped cylinder of any high permeability magnetic material 6 , encloses the coils, except for a gap 65 at the bottom for insertion of a workpiece, such as a resist coated substrate for glass mask production, reticle for projection lithography systems or wafer for direct write integrated circuit exposure. The cap also shields the electron beam from undesirable stray magnetic field influences. [0019] In section 100 of each subsystem, electron gun 105 , illustratively a conventional cathode of LaB 6 crystal that can be controlled and servoed individually to provide high stability and uniformity, generates the subsystem beam. Electrons emitted from gun 105 are accelerated to anode 107 . A first shaping aperture 109 in plate 110 permits the passage of an electron beam having a square cross section, illustratively 175 μm on a side. [0020] Electrostatic deflection plates 112 and 114 deflect the square beam over second shaping aperture 210 in plate 205 to position the square beam from the first shaping aperture appropriately with respect to aperture 210 . As is described in U.S. Pat. No. 4,945,246 for a single beam system, each column generates a shaped beam having a shape that may be a vertical line, a horizontal line or a rectangle of desired shape by deflecting the square beam from aperture 109 such that only a beam of the desired shape passes through aperture 210 . A solenoid field generated in Section 100 by coil 12 - 1 focuses an image of the beam emerging from aperture 109 at the plane of aperture 210 . The number of ampere turns in Section 100 is selected in conjunction with the accelerating voltage of the beam to provide a beam focus in the desired transverse plane. Optionally, a plate 205 of the same magnetically permeable material as enclosure 6 separates the first and second sections of the system. An aperture 206 in plate 205 is oversized to permit the beam to strike shaping aperture 210 without striking plate 205 . [0021] In Section 200 , a demagnifying lens constructed according to the teachings of the referenced copending patent forms a demagnified image of the beam emerging from aperture 210 near the bottom of Section 200 . The lenses will be referred to as “passive” since they are not energized by current within the lens, but achieve a focus by affecting the external solenoid field. High permeability plates 205 and 255 separate the magnetic fields in the three sections, reducing the load on the drivers that power the separate solenoid coils and providing the ability to have several different strength solenoids stacked one on top of each other and thus vary the focal length of each section independently. Illustratively, the coil 12 - 2 for Section 200 is energized with about 2,000 ampere-turns, compound lenses 230 have a magnification of 0.0114, the current density in a beam is about 100A/cm 2 , and the system generates beam “flashes” having a duration of approximately 50 ns, depending on resist sensitivity, beam energy and current density. [0022] The alignment, shaping, blanking and deflection of each beam is accomplished in each subsystem with electrostatic fields to prevent coupling between adjacent beams and to assure that the focal planes in the solenoid field are not affected. Proper alignment of the beam can be assured throughout the column by superimposing offset voltages on the aforementioned shaping, blanking and deflection elements, as is standard in the art. [0023] Conventional electronic circuits for supplying DC voltage, driving the coils and the electrostatic deflectors are shown schematically by box 175 in the lower right of the Figure. Minor refocussing to compensate for demagnification lens field variations and target height changes can be accomplished by introducing a weak Unipotential (Einzel) lens (most easily by utilizing the magnetic lens pole pieces as ground elements and placing a biassed aperture between them), and/or applying a bias voltage to the substrate 60 . [0024] At the bottom of the Figure, Section 300 contains deflector plates 312 and 314 that position each beam at a desired location on workpiece 60 . In this Figure, workpiece 60 moves in and out of the plane of the drawing on a conventional stage shown schematically as box 66 . [0025] A preferred embodiment of the invention having demagnifying lens 230 , having upper pole tips 232 , lower pole tips 234 and high permeability block 236 produced demagnification greater than 80×, while maintaining spherical and chromatic aberration below 4 mm. Other parameters are: a beam voltage of 10 keV, magnification in the upper lens 232 of 0.133, magnification in the lower lens 234 of 0.086, giving a total demagnification of 87 with C SI =3.25 mm, C C =3.83 mm. The excitation of solenoid 12 - 2 was 2000 ampere-turns. The diameter of magnetic intermediate piece 236 was nominally the same as the electrostatic deflectors and 20 mm. The diameter of the bore through the pole pieces was 4 mm and the lens gaps were 4 mm for the upper and lower sections, with 7 mrad aperture half angle at the second demagnification lens image plane. The aperture in the plane of plate 210 is the object and the plane of plate 255 is the approximate location of the second image plane in this case. At the intermediate image plane 212 , there is a limiting aperture that defines the final semi-angle at the target and also minimizes the isotropic off axis aberrations. [0026] Illustratively, the approximate length of the first section was 200 mm, the second 150 mm and the third section 150 mm (to target) for a total system length of approximately 550 mm. [0027] Passive pole pieces 230 in the second section are supported by non-magnetic materials. The deflectors in the first and third sections are supported by non-magnetic, non-conducting materials not shown in the drawing for simplicity. [0028] Referring now to FIG. 2, there is shown a top view of some alternative embodiments of the invention. Illustratively, the system is to write a pattern directly on a wafer or on a mask, which is later to be used in a stepper to expose integrated circuit patterns. For a typical 4× stepper, the area to be exposed extends 3 cm by 4 cm, so that the e-beam system mask must cover an area of 12 cm by 16 cm. Boxes 501 - 506 in the group of two rows denoted by bracket 500 represent schematically e-beam subsystems constructed according to the invention that have an illustrative deflection range of +/−11 mm in the x and y directions. The e-beam systems in the two rows denoted are separated horizontally by 20 mm (e.g. the center of subsystem 503 is 40 mm from the center of subsystem 501 and the x-position of subsystem 502 is located midway between them), so that there is an overlap region of 2 mm in the x-direction. The first and second rows are displaced for convenience in displaying the Figure. Preferably, the two rows are placed with a distance between centers of 20 mm, denoted by bracket 508 , and therefore have the same overlap of 2 mm in the y-direction. [0029] Confining our attention for the moment to the group of a single row divided into even and odd sub-rows together labelled 500 , a preferred method of operation is to transport the workpiece mechanically (on stage 66 in FIG. 1) vertically downward in FIG. 2. Initially, the systems 502 , 504 , 506 in the even subrow write a pattern in a first horizontal strip extending 2 cm in the y-direction and subsystems 501 , 503 and 505 do not write. Next, the stage is moved by 2 cm in the y-direction, so that the spaces not covered by the even subrow (systems 502 - 506 ) in the first step are now covered by systems 501 - 505 in the odd subrow. The remainder of the first horizontal strip is then written by systems 501 - 505 while simultaneously systems 502 - 506 write the next horizontal strip. It will be evident to those skilled in the art that nine iterations will write the desired 16 cm in the y-direction. In the first step, subsystems 501 , 503 and 505 do not write and in the ninth step, subsystems 502 , 504 and 506 do not write. [0030] Alternatively, additional rows denoted with brackets 510 - 570 could be provided, so that the groups collectively cover the area to be written. In that case, just two steps will write out the area. On the first step, subsystems 501 , 503 and 505 do not write and on the second step, subsystems 572 , 574 and 576 do not write. [0031] [0031]FIG. 3 illustrates an alternative embodiment, in which the systems 501 ′, 502 ′, 506 ′ are all in the same single row. In that case, a single step will write a horizontal strip 2 cm along the y-direction. In this embodiment also, additional rows can be provided to reduce the number of steps. When the groups 500 ′, 510 ′, - - - 570 ′ (eight groups) of rows collectively cover the chip, the entire chip can be written in a single step. [0032] In this discussion, it has been assumed that the spacing between groups (rows) is related to the coverage of a group along the y-axis so that one step will bring the top of the nth group to the bottom of the (n+1)th group (not counting overlap). This is not required in general, and the spacing could be made greater, so that it takes k steps to bring the top of the nth group to the bottom of the (n+1)th group, whether an individual group is a single row, as in group 500 ′ of FIG. 3, or staggered rows, as in group 500 of FIG. 2. This approach would reduce the complexity of the hardware and require a longer time to write the entire pattern. [0033] Referring to FIG. 4A, a simplified passive lens for use in the invention modifies the magnetic field lines to form a demagnification lens. Illustratively, the material is Ferrite™, a ceramic with high magnetic permeability, available from the Ceramic Magnetics company. As is conventional, coils 10 and 12 , forming a solenoid field and pole piece 30 have cylindrical symmetry. The axial solenoid field 20 is modified by pole piece 30 to have a very strong peak in the pole piece gap (also referred to as the lens gap) 33 with negative side lobes (relative to the uniform solenoid field). Pole piece 30 has flat top and bottom surfaces 34 and two pole tips 32 , having outer surfaces that make an acute angle with respect to the solenoid axis 101 . In general, the closer the outer surfaces of pole tips 32 are to the vertical, the sharper the peak in magnetic field trace 130 in FIG. 4C and the deeper the dips in field strength 132 and 134 . Preferably, the pole tip surfaces have an angle of less than 45° with respect to the geometric axis. This pole piece configuration has been shown to easily provide demagnification in the 10× range (shown in beam trace 120 in FIG. 2B), with spherical and chromatic aberration coefficients below 3 mm. [0034] Those skilled in the art will appreciate that the unexpectedly low value for the spherical aberration results from the ability of these lenses to create the dips in magnetic field strength 132 and 134 , which have no counterparts in a conventional lenses driven by coils contained within the pole pieces. [0035] To achieve even higher demagnification, two or more of these lenses can be used in the same solenoid field, illustrated in FIGS. 5A and 5B. There, pole pieces 32 are the same as those in FIG. 4A. Segments 34 of the poles are not used in this illustration, but could be added to further strengthen the lens field in the pole piece gap, and thereby increase the demagnification. An optional permeable member 36 , of the same permeable material, merges with lower pole piece 32 of the upper pair and with the upper pole piece 32 of the lower pair, so that a single piece of material 36 conducts the field lines from the upper gap to the lower gap. A single piece eliminates problems with misalignment between the pieces, but is not required. So long as the three pieces abut and carry the field lines, separate pieces can be used. Filling the region between the two lenses with high permeability magnetic material produces a field free region that can be used for separation and demagnification purposes. [0036] While the invention has been described in terms of a few preferred embodiments, those skilled in the art will recognize that the invention can be practiced in various versions within the spirit and scope of the following claims.
A multi-beam e-beam system employs a set of independently controllable (for blanking and deflection) subsystems placed in a solenoid field, each system having a demagnifying lens comprising at least one passive pole piece, so that the final image demagnifies imperfections in the upstream electron beam. Upper and lower sections of the system employ the focusing effect of the solenoid field to form an image at a shaping aperture and a demagnified image of the beam at the shaping aperture on the workpiece. Small focus corrections due to magnetic lens field non-uniformity and/or target height variations, are accomplished with an electrostatic unipotental lens built into the pole pieces and target voltage variations.
Identify and summarize the most critical features from the given passage.
[ "CROSS REFERENCE TO RELATED APPLICATIONS [0001] U.S. patent application Ser.", "No. ______ Docket Number FIS9-2001-0263, assigned to the assignee hereof and filed concurrently herewith discloses types of lenses useful in the practice of the subject invention and is incorporated by reference herein.", "FIELD OF THE INVENTION [0002] The field of the invention is multi-beam electron beam lithography.", "BACKGROUND OF THE INVENTION [0003] It is generally accepted in the mask industry that single beam electron beam mask writers will not be able to deliver the current density at high resolution to achieve exposure speeds required for products below 100 nm GR (Ground Rules).", "The usable current in probe forming systems is limited by stochastic Coulomb interactions, primarily at apertures or beam crossovers, which translates into loss of resolution.", "By contrast, multibeam systems suffer much less from this problem since the total current delivered to the target is spread over many beams, in most cases, each with its own apertures and crossovers.", "[0004] Multibeam systems proposed to date have problems with manufacturing feasibility primarily because of unattainable stability and uniformity requirements placed on the electron sources, i.e. field emitters and photocathodes.", "Some of these systems employ multibeams through part of the optics column but share the same crossover, which does not improve the electron interaction problem.", "Their stability requirements are further magnified since they typically use 1 to 1 imaging of the source at the target.", "[0005] A uniform magnetic field (solenoid field) oriented along the electron beam axis is the simplest of electron lenses and has been employed in various electron beam systems.", "Electrons radiating from a point object execute, by virtue of their transverse velocity component, one cyclotron orbit in the transverse plane, returning to the optic axis.", "Thus, an image is formed with unity magnification.", "A major advantage of the solenoid lens is that there is no prescribed optic axis, hence a shift (deflection) of the beam by a transverse field will cause the beam to shift position, but maintain the same focal plane.", "A major disadvantage of these lenses is that they produce no demagnification of the object, so that defects in the source (reticle, shaping aperture) are reproduced in the image at the same scale.", "[0006] The restriction of lenses formed by solenoid fields in the prior art to a one-to-one object to image ratio imposes severe limitations on the image quality.", "It is well known that the conventional object to image ratio of 4:1 in optical steppers is more “forgiving”, than a 1:1 demagnification ratio.", "[0007] Such a 1:1 magnification ratio in a multiple-beam system is illustrated in U.S. Pat. Nos. [0008] 6,175,122, 5,981,962 and 5,962,859, which show a plurality of shaped-beam systems, contained within the same solenoid field.", "In such a system, imperfections in the aperture result in the same imperfections in the image, thus limiting resolution.", "SUMMARY OF THE INVENTION [0009] The invention relates to a multi-beam lithography system in which a set of electron beam sub-systems having a substantial demagnification are immersed in a solenoid field and operate in parallel.", "[0010] A feature of the invention is the use of a single solenoid field common to several electron beam sub-systems.", "[0011] Another feature of the invention is the use of magnetic lenses having substantial demagnification, so that imperfections in the object are reduced in the image by the demagnification factor.", "BRIEF DESCRIPTION OF THE DRAWINGS [0012] [0012 ]FIG. 1 shows an embodiment of the invention in cross section.", "[0013] [0013 ]FIG. 2 shows a top view of an embodiment of the invention.", "[0014] [0014 ]FIG. 3 shows a top view of an alternative embodiment of the invention.", "[0015] [0015 ]FIGS. 4A, 4B and 4 C show a cross section of a portion of the invention, an associated beam trace and an associated plot of field strength.", "[0016] FIGS. 5 A, and 5 B show a cross section of another embodiment of the invention and an associated plot of field strength.", "DESCRIPTION OF THE PREFERRED EMBODIMENT [0017] Referring now to FIG. 1, there is shown in cross section an embodiment of the invention having three independently controlled variable shape electron beams apparatus immersed in a common solenoid field.", "These subsystems (subsystems in the overall multi-beam system) are positioned in close proximity (on the order of 20 mm center-to-center) and simultaneously expose an array of stitched subfields that together expose the full field pattern, illustratively an integrated circuit.", "The imaging system employs high demagnification of the object, thus suppressing flaws in the source (i.e. the surface of a shaping aperture).", "[0018] The overall solenoid magnetic field is provided by coils 12 - 1 , 12 - 2 and 12 - 3 in sections 100 , 200 and 300 , respectively.", "A capped cylinder of any high permeability magnetic material 6 , encloses the coils, except for a gap 65 at the bottom for insertion of a workpiece, such as a resist coated substrate for glass mask production, reticle for projection lithography systems or wafer for direct write integrated circuit exposure.", "The cap also shields the electron beam from undesirable stray magnetic field influences.", "[0019] In section 100 of each subsystem, electron gun 105 , illustratively a conventional cathode of LaB 6 crystal that can be controlled and servoed individually to provide high stability and uniformity, generates the subsystem beam.", "Electrons emitted from gun 105 are accelerated to anode 107 .", "A first shaping aperture 109 in plate 110 permits the passage of an electron beam having a square cross section, illustratively 175 μm on a side.", "[0020] Electrostatic deflection plates 112 and 114 deflect the square beam over second shaping aperture 210 in plate 205 to position the square beam from the first shaping aperture appropriately with respect to aperture 210 .", "As is described in U.S. Pat. No. 4,945,246 for a single beam system, each column generates a shaped beam having a shape that may be a vertical line, a horizontal line or a rectangle of desired shape by deflecting the square beam from aperture 109 such that only a beam of the desired shape passes through aperture 210 .", "A solenoid field generated in Section 100 by coil 12 - 1 focuses an image of the beam emerging from aperture 109 at the plane of aperture 210 .", "The number of ampere turns in Section 100 is selected in conjunction with the accelerating voltage of the beam to provide a beam focus in the desired transverse plane.", "Optionally, a plate 205 of the same magnetically permeable material as enclosure 6 separates the first and second sections of the system.", "An aperture 206 in plate 205 is oversized to permit the beam to strike shaping aperture 210 without striking plate 205 .", "[0021] In Section 200 , a demagnifying lens constructed according to the teachings of the referenced copending patent forms a demagnified image of the beam emerging from aperture 210 near the bottom of Section 200 .", "The lenses will be referred to as “passive”", "since they are not energized by current within the lens, but achieve a focus by affecting the external solenoid field.", "High permeability plates 205 and 255 separate the magnetic fields in the three sections, reducing the load on the drivers that power the separate solenoid coils and providing the ability to have several different strength solenoids stacked one on top of each other and thus vary the focal length of each section independently.", "Illustratively, the coil 12 - 2 for Section 200 is energized with about 2,000 ampere-turns, compound lenses 230 have a magnification of 0.0114, the current density in a beam is about 100A/cm 2 , and the system generates beam “flashes”", "having a duration of approximately 50 ns, depending on resist sensitivity, beam energy and current density.", "[0022] The alignment, shaping, blanking and deflection of each beam is accomplished in each subsystem with electrostatic fields to prevent coupling between adjacent beams and to assure that the focal planes in the solenoid field are not affected.", "Proper alignment of the beam can be assured throughout the column by superimposing offset voltages on the aforementioned shaping, blanking and deflection elements, as is standard in the art.", "[0023] Conventional electronic circuits for supplying DC voltage, driving the coils and the electrostatic deflectors are shown schematically by box 175 in the lower right of the Figure.", "Minor refocussing to compensate for demagnification lens field variations and target height changes can be accomplished by introducing a weak Unipotential (Einzel) lens (most easily by utilizing the magnetic lens pole pieces as ground elements and placing a biassed aperture between them), and/or applying a bias voltage to the substrate 60 .", "[0024] At the bottom of the Figure, Section 300 contains deflector plates 312 and 314 that position each beam at a desired location on workpiece 60 .", "In this Figure, workpiece 60 moves in and out of the plane of the drawing on a conventional stage shown schematically as box 66 .", "[0025] A preferred embodiment of the invention having demagnifying lens 230 , having upper pole tips 232 , lower pole tips 234 and high permeability block 236 produced demagnification greater than 80×, while maintaining spherical and chromatic aberration below 4 mm.", "Other parameters are: a beam voltage of 10 keV, magnification in the upper lens 232 of 0.133, magnification in the lower lens 234 of 0.086, giving a total demagnification of 87 with C SI =3.25 mm, C C =3.83 mm.", "The excitation of solenoid 12 - 2 was 2000 ampere-turns.", "The diameter of magnetic intermediate piece 236 was nominally the same as the electrostatic deflectors and 20 mm.", "The diameter of the bore through the pole pieces was 4 mm and the lens gaps were 4 mm for the upper and lower sections, with 7 mrad aperture half angle at the second demagnification lens image plane.", "The aperture in the plane of plate 210 is the object and the plane of plate 255 is the approximate location of the second image plane in this case.", "At the intermediate image plane 212 , there is a limiting aperture that defines the final semi-angle at the target and also minimizes the isotropic off axis aberrations.", "[0026] Illustratively, the approximate length of the first section was 200 mm, the second 150 mm and the third section 150 mm (to target) for a total system length of approximately 550 mm.", "[0027] Passive pole pieces 230 in the second section are supported by non-magnetic materials.", "The deflectors in the first and third sections are supported by non-magnetic, non-conducting materials not shown in the drawing for simplicity.", "[0028] Referring now to FIG. 2, there is shown a top view of some alternative embodiments of the invention.", "Illustratively, the system is to write a pattern directly on a wafer or on a mask, which is later to be used in a stepper to expose integrated circuit patterns.", "For a typical 4× stepper, the area to be exposed extends 3 cm by 4 cm, so that the e-beam system mask must cover an area of 12 cm by 16 cm.", "Boxes 501 - 506 in the group of two rows denoted by bracket 500 represent schematically e-beam subsystems constructed according to the invention that have an illustrative deflection range of +/−11 mm in the x and y directions.", "The e-beam systems in the two rows denoted are separated horizontally by 20 mm (e.g. the center of subsystem 503 is 40 mm from the center of subsystem 501 and the x-position of subsystem 502 is located midway between them), so that there is an overlap region of 2 mm in the x-direction.", "The first and second rows are displaced for convenience in displaying the Figure.", "Preferably, the two rows are placed with a distance between centers of 20 mm, denoted by bracket 508 , and therefore have the same overlap of 2 mm in the y-direction.", "[0029] Confining our attention for the moment to the group of a single row divided into even and odd sub-rows together labelled 500 , a preferred method of operation is to transport the workpiece mechanically (on stage 66 in FIG. 1) vertically downward in FIG. 2. Initially, the systems 502 , 504 , 506 in the even subrow write a pattern in a first horizontal strip extending 2 cm in the y-direction and subsystems 501 , 503 and 505 do not write.", "Next, the stage is moved by 2 cm in the y-direction, so that the spaces not covered by the even subrow (systems 502 - 506 ) in the first step are now covered by systems 501 - 505 in the odd subrow.", "The remainder of the first horizontal strip is then written by systems 501 - 505 while simultaneously systems 502 - 506 write the next horizontal strip.", "It will be evident to those skilled in the art that nine iterations will write the desired 16 cm in the y-direction.", "In the first step, subsystems 501 , 503 and 505 do not write and in the ninth step, subsystems 502 , 504 and 506 do not write.", "[0030] Alternatively, additional rows denoted with brackets 510 - 570 could be provided, so that the groups collectively cover the area to be written.", "In that case, just two steps will write out the area.", "On the first step, subsystems 501 , 503 and 505 do not write and on the second step, subsystems 572 , 574 and 576 do not write.", "[0031] [0031 ]FIG. 3 illustrates an alternative embodiment, in which the systems 501 ′, 502 ′, 506 ′ are all in the same single row.", "In that case, a single step will write a horizontal strip 2 cm along the y-direction.", "In this embodiment also, additional rows can be provided to reduce the number of steps.", "When the groups 500 ′, 510 ′, - - - 570 ′ (eight groups) of rows collectively cover the chip, the entire chip can be written in a single step.", "[0032] In this discussion, it has been assumed that the spacing between groups (rows) is related to the coverage of a group along the y-axis so that one step will bring the top of the nth group to the bottom of the (n+1)th group (not counting overlap).", "This is not required in general, and the spacing could be made greater, so that it takes k steps to bring the top of the nth group to the bottom of the (n+1)th group, whether an individual group is a single row, as in group 500 ′ of FIG. 3, or staggered rows, as in group 500 of FIG. 2. This approach would reduce the complexity of the hardware and require a longer time to write the entire pattern.", "[0033] Referring to FIG. 4A, a simplified passive lens for use in the invention modifies the magnetic field lines to form a demagnification lens.", "Illustratively, the material is Ferrite™, a ceramic with high magnetic permeability, available from the Ceramic Magnetics company.", "As is conventional, coils 10 and 12 , forming a solenoid field and pole piece 30 have cylindrical symmetry.", "The axial solenoid field 20 is modified by pole piece 30 to have a very strong peak in the pole piece gap (also referred to as the lens gap) 33 with negative side lobes (relative to the uniform solenoid field).", "Pole piece 30 has flat top and bottom surfaces 34 and two pole tips 32 , having outer surfaces that make an acute angle with respect to the solenoid axis 101 .", "In general, the closer the outer surfaces of pole tips 32 are to the vertical, the sharper the peak in magnetic field trace 130 in FIG. 4C and the deeper the dips in field strength 132 and 134 .", "Preferably, the pole tip surfaces have an angle of less than 45° with respect to the geometric axis.", "This pole piece configuration has been shown to easily provide demagnification in the 10× range (shown in beam trace 120 in FIG. 2B), with spherical and chromatic aberration coefficients below 3 mm.", "[0034] Those skilled in the art will appreciate that the unexpectedly low value for the spherical aberration results from the ability of these lenses to create the dips in magnetic field strength 132 and 134 , which have no counterparts in a conventional lenses driven by coils contained within the pole pieces.", "[0035] To achieve even higher demagnification, two or more of these lenses can be used in the same solenoid field, illustrated in FIGS. 5A and 5B.", "There, pole pieces 32 are the same as those in FIG. 4A.", "Segments 34 of the poles are not used in this illustration, but could be added to further strengthen the lens field in the pole piece gap, and thereby increase the demagnification.", "An optional permeable member 36 , of the same permeable material, merges with lower pole piece 32 of the upper pair and with the upper pole piece 32 of the lower pair, so that a single piece of material 36 conducts the field lines from the upper gap to the lower gap.", "A single piece eliminates problems with misalignment between the pieces, but is not required.", "So long as the three pieces abut and carry the field lines, separate pieces can be used.", "Filling the region between the two lenses with high permeability magnetic material produces a field free region that can be used for separation and demagnification purposes.", "[0036] While the invention has been described in terms of a few preferred embodiments, those skilled in the art will recognize that the invention can be practiced in various versions within the spirit and scope of the following claims." ]
FIELD OF THE INVENTION [0001] This invention relates to the field of optical networks and more specifically, to rapidly quantifying the needs and costs of optical networks. BACKGROUND OF THE INVENTION [0002] The technology and architecture for circuit and packet communication networks continue to evolve, and converge. Fundamental to the comparison and selection of network architectures and their technological implementations is the total cost of ownership of the network. This cost includes the expenses for capital equipment (CAPEX), network operation (OPEX), and network management (MANEX). While operational and management expenses represent the largest share of the total cost of ownership, capital costs are a considerable and highly visible portion of the initial investment. Equipment cost is therefore a very important factor in the choice of architecture and technology. Therefore, a model for very quickly gauging the network equipment needs and costs is needed. SUMMARY OF THE INVENTION [0003] The present invention provides a network global expectation model for estimating the number of network elements, network elements characteristics, and costs of communication networks using analytic formulae. The network global expectation model includes the calculation of both the mean value and variance of all key network quantities and may be applied to a wide range of topologies, architectures, and demand profiles. [0004] The network global expectation model of the present invention uses expectation values as a multi-moment description of the required quantities of key network and network element (NE) resources and commensurate network costs. This approach naturally, analytically, and accurately connects the global (network) and local (network element) views of the communication system. As a result, the model may be used as a tool to gain insight and quickly provide approximate results for preliminary network evaluation and design, element feature requirements, costs, sensitivity analyses, scaling performance, comparisons, product definition and application domains, and product and technology road-mapping. [0005] The network global expectation model of the present invention is adaptable to both increasing and decreasing levels of detail and sophistication of the cost structures. Because of the analytic nature of the model the estimates of quantities may be computed much faster than is possible with detailed routing solvers, and so the model is ideally suited to network analyses in dynamic operating and technological environments. The uncomplicated and transparent accounting of network elements, systems, and costs inherent in the network global expectation model of the present invention constitutes a framework for the cooperative exchange of critical planning information on evolving network needs across the many sectors of the communication business. BRIEF DESCRIPTION OF THE DRAWINGS [0006] The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which: [0007] FIG. 1 depicts a high level abstract representation of a mesh network wherein an embodiment of the present invention may be applied; [0008] FIG. 2 depicts a high level representation of a prototypical backbone network wherein an embodiment of the present invention may be applied; [0009] FIG. 3 a depicts a high level block diagram of an exemplary cross-connect and line system arranged to illustrate five two-way ports (North, South, East, West, and Termination) service by a cross-connect wherein an embodiment of the present invention may be applied; [0010] FIG. 3 b depicts a high level block diagram of the system of FIG. 3 a arranged to illustrate five one-way ports (five inputs and five outputs); [0011] FIG. 4 graphically depicts a plot of the termination-to-termination traffic, τ, for uniform demand as a function of the number of nodes, N, and total network traffic, T. [0012] FIG. 5 graphically depicts a plot of the mean traffic on a link including idle restoration channels for uniform demand as a function of the number of nodes N and total network traffic T; [0013] FIG. 6 depicts a high level block diagram of two cross-connect ports and the relationship among the local ADD, DROP and THRU channels; [0014] FIG. 7 depicts a high level block diagram of an exemplary Bandwidth Management Architecture using both optical and electronic cross-connects; [0015] FIG. 8 graphically depicts an illustrative comparison of bandwidth management costs; and [0016] FIG. 9 graphically depicts a contour map of the total cost of a mesh network with uniform demand as a function of the number of nodes N and total traffic T. DETAILED DESCRIPTION OF THE INVENTION [0017] Although various embodiments of the present invention herein are being described with respect to various communication networks, such as backbone, fiber-optic transport networks and mesh networks, it should be noted that the specific communication networks are simply provided as exemplary environments wherein embodiments of the present invention may be applied and should not be treated as limiting the scope of the invention. It will be appreciated by those skilled in the art informed by the teachings of the present invention that the concepts of the present invention are applicable in substantially any network wherein it is desirable to quickly gauge the network equipment needs and costs. [0018] In the present invention, a general formalism of the global network expectation model is developed and application illustrated by considering single-tier backbone networks with location-independent traffic demands. While the methodology presented herein is very general, for specificity the application is described throughout the specification in the context of mesh networks. [0019] As the cost of a network for a specified set of features is considered the metric for comparison of architectures and technologies, the inventor proposes that the total network cost is exactly the sum of the costs of the constituent parts, or elements, of the network. This fundamental accounting of costs may be written mathematically according to equation one (1), which follows: C T ≡ ∑ i ⁢ c i , ( 1 ) where C T is the total network cost and c i is the unit cost of the ith component (herein and throughout this disclosure the symbolic notation Σ indicates the summation over the various contributing terms, in this case the many individual components.) [0021] It is usual that there are many components of a given type used throughout the network, and these identical parts share a common cost. In this case using the associative, commutative, and distributive properties of the field of real numbers, equation (1) above may be rewritten according to equation two (2), which follows: C T = ∑ i ⁢ v i ⁢ c i , ( 2 ) where again C T is the total network cost, v i is the number of network elements of type i, and c i is the corresponding unit cost of network element of type i. [0023] Without loss of generality it may be assumed that the technology and corresponding unit costs, c i , of the network elements used to construct the network are known, i.e., given apriori. The challenge of network design is to determine the number, v i , and placement of each of the network elements of the given types to minimize the total network cost under the constraint to service a specified traffic demand among the network terminations located at specific geographic locations. The strategy of the model of the present invention is to carefully estimate the products of the network element counts and respective costs while satisfying the external constraints, and thereby to estimate the total network cost using equation (2) above, but without explicitly establishing knowledge of the placement of every individual component within the network. [0024] The sum in equation (2) does not distinguish among the various categories of network elements, but considers each contributing type as atomic (i.e., indivisible). Without changing the value of the sum, terms may be collected that are logically related to one another into a cost subtotal for larger categories of elements. Denoting a general set of categories as α, equation (2) may be rewritten according to equation three (3), which follows: C T = ∑ α ⁢ ∑ i ⁢ v i ⁡ ( α ) ⁢ c i ⁡ ( α ) . ( 3 ) One useful subdivision for separating costs is based on collecting the costs for signal transmission (TRANS) and signal bandwidth management (BWM) into separate terms. In this case equation (3) above may be rewritten according to equation four (4), which follows: C T = ∑ TRANS ⁢ v i ⁢ c i + ∑ BWM ⁢ v j ⁢ c j , ( 4 ) The transmission term might include, for example, objects such as optical transceivers (OT), optical multiplexers (OMUX), and optical amplifiers (OA). The bandwidth management term might include objects such as multi-service platforms (MSP), electronic cross-connects (EXC), optical add/drop multiplexers (OADM), and optical cross-connects (OXC). Of course, which objects are to be associated with particular categories is a matter of architectural choice. [0027] FIG. 1 depicts a high level abstract representation of a mesh network wherein an embodiment of the present invention may be applied. The mesh network 100 of FIG. 1 comprises a plurality of nodes (illustratively 6 nodes) 110 1 - 110 6 (collectively nodes 110 ), where traffic may enter and leave the mesh network 100 , a plurality of terminals (illustratively 6 terminals 115 1 - 115 6 ) (collectively terminals 115 ) connected to the nodes 110 , which are the sources and sinks of traffic in the network 100 , and a plurality of inter-nodal links (illustratively 9 links 120 1 - 120 9 ) (collectively links 120 ), which represent the physical segments over which the inter-terminal traffic may be carried, or transported, between the nodes 110 . The total number of nodes and links of the mesh network 100 of FIG. 1 are denoted by N and L, respectively. The average degree of node in the mesh network 100 of FIG. 1 is δ =3 for N=6 nodes and L=9 links. [0028] FIG. 2 depicts a map of the United States of America comprising an illustration of an exemplary mesh network, such as the mesh network 100 of FIG. 1 , wherein an embodiment of the present invention may be applied. FIG. 2 depicts a core fiber transport network typical of larger inter-exchange carriers of the continental United States. The example network 200 of FIG. 2 illustratively comprises 100 nodes and 171 links. The average degree node is δ =3.4, and the average number of minimum hops between node pairs is h =6.6. [0029] As suggested by the view of the mesh networks illustrated in FIG. 1 and FIG. 2 , the total network cost, C T , may also be represented by terms that correspond to the L links and N nodes of the network according to equation five (5) or equation six (6), which follow: C T = ∑ l L ⁢ c l + ∑ n N ⁢ c n , ⁢ or ( 5 ) C T = ∑ LINKS ⁢ c l + ∑ NODES ⁢ c n , ( 6 ) where c i is the cost of the lth link and c n is the cost of the nth node. If the first term of equation (5) above is multiplied by the factor L/L and the second term by N/N and note that the expectation value, q , or average, of a set of values {q i } i=1, m is defined according to equation seven (7), which follows: 〈 q 〉 = 1 m ⁢ ∑ i m ⁢ q i , ( 7 ) then equation (5) above may be rewritten according to equation eight (8), which follows: C T =L<c i >+N<c n >.  (8) Thus, as expressed in Eq. 8 the exact cost of the network may be considered as the sum of the expectation value of the cost of a link times the number of links and the expectation value of the cost of a node times the number of nodes. The global expectation values (c i ) and (c n ) are themselves explicitly defined according to equations (9a) and (9b), which follow: 〈 c l 〉 = ∑ i ⁢ 〈 v i 〉 l ⁢ c i , ⁢ and ( 9 ⁢ a ) 〈 c n 〉 = ∑ j ⁢ 〈 v j 〉 n ⁢ c j . ( 9 ⁢ b ) Note, throughout this disclosure, the bracket notation, , will be used to denote the expectation value of a variable. In instances when the corresponding set {q} of an expectation value q may be ambiguous, the right bracket of the expectation value may be followed by a subscript to provide clarification. For example, in equation (9a) above, ν i l indicates an expectation value over the set of links {l} and in equation (9b) above, ν j n indicates an expectation value over the set of nodes {n}. Also regarding expectation values, here the elements q i of the set {q} are not samples of a variable associated with either a discrete or continuous probability distribution, but rather define a distribution. [0034] The relationship of network cost to link and node costs embodied in equations (8-9) above could have served as the starting point of this discussion, however, the inventor has decided to begin the discussion of the present invention instead using equation (1) to firmly establish that the use of expectation values, or averages, to determine the total network cost is not an approximation, but is exact. The approximations of the global expectation model(s) reside instead in the estimation of the expectation values of the quantities of network elements, ν . Consequently, the predictive capability of the model will depend upon the accuracy of the estimations of these mean values and the applicability of other related assumptions, such as the demand model. As will be demonstrated herein, for many variables the expectation values may be computed exactly from the input variables for a given demand model, while for other variables it is necessary to introduce semi-empirical approximations. [heading-0035] Network and Primary Model Variables [0036] Referring back to FIG. 1 and FIG. 2 , a communication network has been defined as the combination of a network graph, denoted G, consisting of a set of N nodes {n i } and set of L connecting two-way links, or edges, {l i }, and a network traffic. The network graph may be represented by the symmetric matrix [g] with elements g ij . The pair-wise communication traffic between nodes may be represented by the symmetric demand matrix [d] with elements d ij and the total ingress/egress traffic T. [0037] The matrix elements g ij are either 0 or 1 in value and specify whether a pair of nodes is connected via a physical link. The summation of all the values of the matrix elements of [g] yields the number of one-way links L 1 , which is twice the number of two-way links, L 2 . The demand matrix elements d ij are either 0 or a positive integer and denote the magnitude of the termination-to-termination traffic in quantized units of some basic measure of communication bandwidth, such as a standardized channel bit-rate, B. The summation of all the values of the matrix elements of [d] yields the number of one-way demands D 1 , which is twice the number of two-way demands D 2 . It should be noted that, generally the diagonal elements of [g] and [d] are zero. The demands are also often referred to as logical links. [0038] Often the channel bit-rate is not explicitly given for the network of interest. Instead, the total ingress/egress traffic T and number of demands are specified. In that case a value of the termination-to-termination τ traffic must be deduced, and from this a logical value of B may be chosen. It is for this reason that here the total two-way traffic is considered T 2 , which is one-half the total one-way traffic T 1 , to be an independent variable and for τ to be a dependent variable. Having chosen T as an independent variable, a complete set of model inputs is obtained, namely; G(N,L), D, and T together with a demand model. The inventor demonstrates herein that all other variables of interest may be derived from these variables. [0039] In counting quantities such as links, demands, traffic, etc. it is necessary to distinguish between one-way (simplex) and two-way (duplex) variables. As indicated above, the number of two-way links, demands, and traffic is one-half the corresponding number of one-way values. These relationships are illustrated in FIG. 3 a and FIG. 3 b (described below), and formally summarized according to equations (10a), (10b) and (10c), which follow: Links: L = L 2 = L 1 /2 (10a) Total Traffic: T = T 2 = T 1 /2 (10b) Total Demands: D = D 2 = D 1 /2 (10c) [0040] FIG. 3 a depicts a high level block diagram of an exemplary cross-connect and line system wherein an embodiment of the present invention may be applied. The cross-connect and line system 300 of FIG. 3 a illustratively comprises five two-way ports 310 - 314 (illustratively, North, South, East, West and Termination ports) serviced by the cross-connect 320 . [0041] FIG. 3 b depicts a high level block diagram of the cross-connect and line system 300 of FIG. 3 a arranged to illustrate five one-way ports 330 - 334 (five input ports and five output ports). It is typical to define a two-way channel of bandwidth B as the combination of two one-way channels, XY and YX, each of bandwidth B. That is the single value B describes both the one-way and two-way channels. This is evident in the examples depicted in FIG. 3 a and FIG. 3 b . Also, considering the trivial case of two nodes, N=2, and one two-way link, L=1, the total one-way traffic is T 1 =2B, and the total two-way traffic is T=T 2 =B. Of course, so long as one-way or two-way variables are used consistently, or the proper conversion is made, the results and conclusions are the same. For example, B=T 2 /D 2 =T 1 /D 1 . Referring back to FIG. 3 a and FIG. 3 b , it should be noted that the numbers of one-way and two-way ports are identical, i.e., P 1 =P 2 . Also, the channel bit-rate B, or alternatively the termination-to-termination traffic, τ, describes both the one-way and two-way traffic between terminating nodes. [0042] The output variables that are determined by the network global expectation model given the small number of inputs are many. Among them are the termination-to-termination traffic rate and expectation values and variances for the degree of node, number of hops, wavelengths on a link, traffic on a link, restoration capacity, number of ports on a cross-connect, total capacity of a cross-connect, and percentage add/drop at a node. With these expectation values and a cost model for the individual elements the total network cost may be computed. [heading-0043] Single-Tier Networks with Location-independent Demands [0044] To introduce the global expectation model a single-tier network consisting of a set of peer nodes and uniform, fully-connected inter-terminal demands is first considered. While this may seem restrictive, in fact the network global expectation model may be applied to a wide range of network topologies, architectures, and demand profiles. This will become evident as the expectation values and general relationships that are independent of the details of the topology, architecture, and demand are formulated and derived. Additionally, the specific results for uniform demand may also be useful in gauging key quantities for non-uniform demand profiles. For example, in the case of non-uniform demand that is not correlated with the absolute or relative location of terminal pairs (eg. random demand), uniform demand may be considered an average representation on the non-uniform demand. Also, one may envision restructuring an otherwise non-uniform network by grooming the traffic and truncating the set of nodes to produce a core network approaching the characteristics of a single-tier network with uniform demand. Having developed the general formalism here, in future works additional topologies, architectures, and profiles of interest will be explicitly considered. [0045] Most core networks carry symmetric traffic between nodes, and so working with two-way variables is the norm. However, in some instances visualizing and counting one-way variables may be more intuitive, such as tracking a one-way demand from source to destination. Of course following two-way demands from termination to termination is equivalent. In the following, expressions will be explicitly developed using both one-way and two-way input variables for utmost clarity. In very many cases the definition of output variables is such that the values do not change when switching between the one-way and two-way perspectives, as was previously illustrated. [0046] Throughout the following, the model of the present invention will be applied to estimate key characteristics of two example networks. The first example network is the network 200 depicted in FIG. 2 , which consists of 100 nodes and 171 links, uniform demand, and total two-way network traffic of 5 Tb/s. A second example network (not shown) is of similar topology and consists of 25 nodes and 42 links, uniform demand, and total two-way traffic of 1 Tb/s. [heading-0047] Number of Demands [0048] The number of nodes, N, the total two-way traffic, T, and number of two-way links, L, are inputs of the model. The traffic demand is also an input of the model. The total number of demands is explicitly and, of course, straightforwardly related to the numbers of demands terminating at the individual nodes. The one-way demands terminating at node i may be related to the elements of the demand matrix [d], viz. d i =Σ N d ij . Summing the terminating one-way demands, the total one-way and total two-way demands may be related to the mean number of terminating demands at a node, d n , according to equations (11a) and (11b), which follow: D 1 = ∑ i N ⁢ d j = N N ⁢ ∑ i N ⁢ d i = N ⁢ 〈 d 〉 n , ⁢ and ( 11 ⁢ a ) D ≡ D 2 = D 1 2 = 1 2 ⁢ N ⁢ 〈 d 〉 n . ( 11 ⁢ b ) The above expressions in equations (11a) and (11b) are independent of the details of the demand model. The uniform demand model specifies that there is a one-way demand from every node to every other node, or a two-way demand between every node-node pair of the N nodes. Thus, the expression for uniform demand may be characterized according to equations (11c), (11d) and (11e), which follow: d n =N− 1  (11c) and D 1 =N ( N− 1)  (11d) D≡D 2 =N ( N− 1)/2  (11e) Using the equations above, the number of two-way demands may be calculated for the two example networks described above. For example, the number of two-way demands (logical links) for the example network 200 of FIG. 2 having N=100 nodes and L=171 physical links is D=4,950. The number of two-way demands for the second example network described above having N=25 nodes and L=42 links is D=300. Termination-to-Termination Traffic [0053] The value of the termination-to-termination traffic, τ, can be computed exactly as the ratio of the total ingress/egress traffic, T, and total number of two-way network demands, D, terminating at all nodes. As such, the value of termination-to-termination traffic, τ, may be characterized according to equations (12a) and (12b), which follow: τ≡ T 1 /D 1 =T 2 /D 2 =T/D,   (12a) and for uniform demand τ≡ T/[N ( N− 1)/2].  (12b) The total traffic, T, and total number of demands, D, define the termination-to-termination traffic, τ, as indicated by the relationship expressed in Eq. 12a, which is independent of the demand model. As the total traffic and the number of demands define the termination-to-termination traffic, τ, the value of τ is uniquely specified and as such its variance is exactly zero. [0056] FIG. 4 graphically depicts a plot of the termination-to-termination traffic, τ, for uniform demand as a function of the number of nodes, N, and total network traffic, T. In FIG. 4 , the termination-to-termination traffic, τ(N,T) for uniform demand is graphed as a function of the number of nodes, N, and total two-way traffic, T, using a contour plot. [0057] The termination-to-termination traffic, τ, for the example network 200 of FIG. 2 having N=100 nodes, L=171 links and total traffic of T=5 Tb/s is τ=1.01 Gb/s. This may be compared to τ=3.3 Gb/s for the example network having N=25 nodes, L=42 links, and total traffic of T=1 Tb/s. The channel bit-rate is smaller for the larger network because the number of demands for the larger network is significantly greater than for the smaller network. [heading-0058] Degree of Node [0059] The average degree of a node, δ , (i.e. δ n ), is calculated straightforwardly by summing the number of one-way (directed) links and dividing by the number of nodes. Referring back to the matrix representation [g] of the network graph of FIG. 1 and FIG. 2 , the average degree of node may be characterized according to equations (13a) and (13b), which follow: δ i = ∑ j N ⁢ g ij ⁢ ⁢ and ⁢   ⁢ so ( 13 ⁢ a ) 〈 δ 〉 = 1 N ⁢ ∑ i N ⁢ ∑ j N ⁢ g ij = L 1 N = 2 ⁢ L 2 N = 2 ⁢ L N . ( 13 ⁢ b ) This compact expression for (δ) is exact and independent of the demand model. [0061] The variance σ 2 (q) and standard deviation σ(q) of the set of values for the network variable q, are characterized according to equations (13c) and (13d), which follow: σ 2 ⁡ ( q ) = 1 _ ⁢ ∑ m ⁢ ( q i - 〈 q 〉 ) 2 , ( 13 ⁢ c ) m i which may be rewritten as σ 2 ( q )≡ q 2 − q 2 .  (13d) As previously noted, the set {q} is not a sampled data set, but defines the distribution. Furthermore, the standard deviation of a network variable is not an indication of the accuracy or error of the model, but rather it is a measure of the variation of the number of network elements or subsystems from locale to locale across the network. Note too that the value of the mean is independent of the variance. Thus, for example, the total cost for bandwidth management may be accurately predicted even while some nodes are smaller and cost less, and others are larger and cost more. [0065] The variance of the degrees of nodes is defined according to equation (13e), which follows: σ 2 (δ)≡ δ 2 − δ 2 ,  (13e) and so like δ i and δ , σ 2 (δ) is a function only of the network graph, G. Note, however, unlike δ there is no closed form expression for σ 2 (δ) as a function only of N and L. Rather the variance of the degrees of nodes implicitly depends upon the details of the network connectivity and must be computed from a representation of the graph, such as [g] or an equivalent link-list. If the network graph, or equivalently the link-list, is provided then functions of the degrees of nodes, such as the variance, may be computed exactly. [0067] As δ and L are directly proportional and the variance of δ is more closely related to [g], in some situations it may be useful to consider δz, 901 as the independent input variable and L as the dependent output variable. [0068] For the example network 200 of FIG. 2 having N=100 nodes and L=171 links, the mean degree of node is δ =3.4. The standard deviation of the nodal degree obtained from the network graph ( FIG. 2 ) is σ(δ)=1.1. By design, the mean degree of node and standard deviation of the nodal degree for the second example network having N=25 nodes and L=42 links are also δ =3.4 and σ(δ)=1.1. [heading-0069] Number of Hops [0070] The number of hops between a pair of nodes is defined as the minimum number of inter-nodal links traversed by a demand between the terminating node pair. Algorithms for determining the minimum number of hops h ij between node pairs (i,j) from the matrix representing the network graph [g] are well known, and so [h] and h may be readily computed given a demand model. The expectation value of the minimum number of hops is over the set of demands, (e.g., h d ), and may be characterized according to equation (14a), which follows: 〈 h 〉 = 1 D ⁢ ∑ i < j   ⁢ D ⁢ h ij = 1 2 ⁢ D ⁢ ∑ i , j D ⁢ h ij . ( 14 ⁢ a ) If the network graph and demands are provided, then (h) may be computed exactly. However, h may also be approximated for uniform, location-independent, or random demands with knowledge only of the number of nodes and number of links, as will be discussed in more detail below. [0072] The dependency of the average number of hops on the number of nodes N and number of links L may be formulated by considering the schematic of the network graph. If the outer boundary of the N nodes of a planar network arranged is visualized roughly as a square with {square root}N nodes on each of the two orthogonal sides, the characteristic distance between nodes measured in units of hops scales as {square root}N for uniform demand. In addition, the mean number of hops decreases as the number of links L increases for fixed N. An approximate analytic relationship describing the dependency of the mean number of hops on the number of nodes N and the mean degree of the nodes, δ , may be derived by considering a single node at the center of a regular network of constant degree, δ. In this case, the mean number of hops is approximately h ≅0.94{square root}(N−1)/ δ ′. This expression slightly under predicts the correct result in the special case where each node is connected directly to every other node via a dedicated physical link (i.e. δ=N−1 and h ≡1). Brute force evaluation of the mean number of hops for regular networks of constant degree for δ=3 and δ=4, except for the nodes at the perimeter, yields h ≅1.2{square root}N/< δ ′, which slightly over-predicts the means number of hops for the special case of δ=N−1 and h ≡1. [0073] In order to provide accurate compact analytic expressions for all variables for a wide range of networks, the inventor analyzed the average number of hops of several prototypical networks that were designed to be survivable under all possible single link failures. (Note, the failure of a single link implies the simultaneous failure of all demands appearing on the specified inter-nodal segment, which may be a very large number of demands.) This feature of network survivability translates into the requirement that the degrees of nodes for all nodes be greater than or equal to two (i.e., δ≧2). The exact results for the mean number of hops were fitted using the method of least squares deviation to determine the single coefficient of proportionality that best describes the data for all the networks considered. In total data for 14 mesh networks with numbers of nodes spanning the range 4≦N≦100 and average degree of node spanning the range 2.5≦(δ)≦5 were included. It was determined by the inventor that the expectation value of the number of hops for these networks with uniform demand may be expressed semi-empirically by the relation of equation (14b), which follows: h ≅1.12 {square root}{square root over (N/δ)}   (14b) with a standard deviation of approximately 10 percent, and more accurately by the relation h ≅{square root}( N− 2){overscore (/( δ −1))},  (14c) with a standard deviation of approximately 2 percent. [0076] These approximate formulae may be applied to the case of uniform, location-independent, or random demand. For fixed network topology, it is expected for the average number of hops to decrease for distance dependent demand models that weigh shorter distance demands more heavily than longer distance demands. [0077] The estimate of the mean number of hops for the example network 200 of FIG. 2 having N=100 nodes and L=171 links determined using equation (14c) above is h ≅6.1, which may be compared to the actual mean of h =6.6. For the example network having N=25 nodes and L=42 links, the mean number of hops determined using equation (14c) is approximately h ≅3.0. [0078] The variance of the number of hops may be computed from [h] using equation (13); however, it is not necessary to compute σ 2 (h) explicitly for the analyses that follow. The range of hops extends from 1 to some maximum number H, which is often referred to as the diameter of the network. [heading-0079] Demands on Link [0080] It is evident that as a demand d ij is routed across the network between terminating nodes (i,j) that the demand occupies a unit of transmission capacity on each of the links connecting the nodes. The minimum number of links occupied by a demand is, of course, the minimum number of hops h ij from node i to node j. Consequently, the average number of demands carried on a link in the absence of extra capacity for restoration may be characterized according to equations (15a) and (15b), which follow: 〈 W 0 〉 = 1 L ⁢ ∑ i L ⁢ D i × 1 = 1 L ⁢ ∑ i , j D ⁢ 1 × h ij = 1 L ⁢ D D ⁢ ∑ i , j D ⁢ h ij = D ⁢ 〈 h 〉 D L , ( 15 ⁢ a ) which may be rewritten in the convenient form W 0 = d h / δ   (15b) using equations (11b) and (13b). The expression of equation (15b) is exact and valid and independent of the demand model; however, the value of h is implicitly dependent upon the demand model, as discussed earlier. In the cases of uniform or random demand, if an approximation for h such as equations (14b) or (14c), is used to compute W 0 , then of course the result is also approximate, and the relative error of h determines the relative error of W 0 . [0083] For uniform demand, the value for d in equation (15b) may be substituted to obtain equation (15c), which follows: W 0 =( N− 1) h / δ .  (15c) Using equation (15c), the mean number of channels carried on a link for the first example network 200 of FIG. 2 having N=100 nodes and L=171 links ( δ =3.4 and h ≅6.1) is estimated to be W 0 ≅178. Similarly, the mean number of channels on a link for the second example network having N=25 nodes and L=42 links ( δ =3.4 and h ≅3.0) is estimated to be W 0 =22. [0085] As suggested by equation (15b), variations in the number of channels carried on the individual links of the network may arise from differences in the number of demands terminating at the nodes connected to the links, the degrees of the nodes connected to the link, and also the routing constraints and algorithms. Here the case of uniform demand is considered, and the fluctuations that may arise when the demands are routed across the network under the constraint of minimum hop routing are first considered. In general, for any pair of nodes there will be one or more routes of minimum number of hops between the nodes. Consequently, the variation in the number of channels carried on a link will depend upon the selection criteria for choosing from among the set of minimum hop routes, which are referred to by the inventor as hop-degenerate routes. If it is assumed that the path is selected at random from the hop-degenerate routes, then the variance may be estimated using statistical methods. In particular, for the scenario just described, the distribution of the demands among the minimum hop routes is described by the binomial distribution. As such, an approximate expression for the variance of W o is derived by the inventor considering random routing over paths of equal numbers of hops. [0086] Referring back to equations (15a)-(15c) above, the mean value for the number of channels on a link for uniform two-way demand may be explicitly characterized according to equation (15d), which follows: 〈 W 0 〉 = 1 L ⁢ 1 2 ⁢ ∑ i N ⁢ ∑ j N - 1 ⁢ h ij = N ⁡ ( N - 1 ) ⁢ 〈 h 〉 / 2 ⁢ L . ( 15 ⁢ d ) [0087] For a given node pair (i,j), all the paths of minimum hops h ij between them are considered, and l ij is used to denote the total number of distinct links among the set of hop-degenerate routes. These distinct links are labeled using the subscript k and p k is used to denote the probability that a link is selected. By construction, the set of probabilities {p k } satisfies equation (15e), which follows: h ij = ∑ k I ij ⁢ p k , ( 15 ⁢ e ) and consequently, p k ≅h ij /l ij . As an example, consider an illustrative case when there are three (r=3) link-disjoint routes of four (h=4) (minimum) hops between a pair of nodes. In this case l ij =r×h=3×4=12. As the paths are assumed to be disjoint, we may use equation (15e) to solve for p k with the result p k =h ij /l ij =h/(rh)=1/r=⅓ for each link. [0089] Substituting equation (15e) into equation (15d) results in equation (15f), which follows: 〈 W 0 〉 = 1 2 ⁢ L ⁢ ∑ i N ⁢ ∑ j N - 1 ⁢ ∑ k I ij ⁢ p k . ( 15 ⁢ f ) Using the properties of the binomial distribution, the corresponding variance σ 2 (W o ) may be characterized according to equations (15g) and (15h), which follow: σ 2 ⁡ ( W 0 ) = 1 2 ⁢ L ⁢ ∑ i N ⁢ ∑ j N - 1 ⁢ ∑ k I ij ⁢ p k ⁡ ( 1 - p k ) , ( 15 ⁢ g ) using equations (15e) and (15f), equation (15g) may be rewritten as σ 2 ⁡ ( W 0 ) = 〈 W 0 〉 ⁡ [ 1 - 1 N ⁡ ( N - 1 ) ⁢ 〈 h 〉 ⁢ ∑ i N ⁢ ∑ j N - 1 ⁢ ∑ k I ij ⁢ p k 2 ] . ( 15 ⁢ h ) [0092] To evaluate the sums we next group the sum over the N−1 nodes into sets of constant numbers of hops, h. Let there be N h nodes of h hops, and label each node by the index n. For each node the number of distinct links among the possible routes of h hops is denoted l n,h . If H is the largest value of the set of minimum number of hops, then equation (15h) may be rewritten according to equation (15i), which follows: σ 2 ⁡ ( W 0 ) = 〈 W 0 〉 ⁡ [ 1 - 1 〈 h 〉 ⁢ 1 N ⁢ ∑ i N ⁢ 1 N - 1 ⁢ ∑ h H ⁢ ∑ n N h ⁢ ∑ k I nh ⁢ p k 2 ] . ( 15 ⁢ i ) The above expression is exact under the assumption of uniform demand and random routing. [0094] To carry this result further, an approximation for a planar network of average degree <δ> is derived. In this case the maximum number of hops H is characterized according to equation (15j), which follows: N− 1= δ [ H ( H+ 1)]/2,  (15j) and the value of H is related to h by H≅{square root}2 h . [0096] When focusing on a single node within the network, the nodes that may be reached in h minimum hops are identified as approximately δ h in number. The options for routing from the node under consideration to each of the other nodes h minimum hops away are subsequently considered. There is at least one possible route and the number of hop-degenerate routes are denoted by the inventor as r. Next, the number of distinct links l n,h among these r hop-degenerate routes are identified and counted. For the planar network, the number of distinct links l n,h is less than h 2 ; the latter being the number in the situation when the hop-degenerate routes are link-disjoint paths. Consequently, the probability any one link is selected when choosing a path randomly from among the hop-degenerate routes of the network is greater than 1/h, which may be characterized according to (15k), which follows: p k ≧1 /h.   (15k) This expression for the probability that a link is selected permits the formal bounding of the variance of the number of channels. Substituting equation (15k) into equation (15i), carrying out the sums and using equation (15j) yields equations (15l) and (15m), which follow: σ 2 ⁡ ( W 0 ) ≤ 〈 W 0 〉 ⁡ [ 1 - 1 / 〈 h 〉 ] ⁢   ⁢ and ( 15 ⁢ l ) σ ⁡ ( W o ) 〈 W 0 〉 ≤ 1 - 1 〈 h 〉 / 〈 W 0 〉 ≤ 1 √ 〈 W 0 〉 ( 15 ⁢ m ) [0098] The form of the variance in equation (15l) is that of a binomial distribution with probability 1/<h>. Thus, the actual distribution is approximated by the corresponding binomial distribution F(W=w), which is characterized according to equations (15n)-(15q), which follow: F ( W=w )=( w max |w ) p w (1 −p ) w max −w , w= 0, 1 , . . . , w max   (15n) with p= 1/ h   (15o) w max ≡ W 0 h   (15p) and ( w max |w )= w max !/[w !( w max −w )!].  (15q) The binomial tail probability F(W≧w) may be determined using the incomplete beta function. [0101] Using Eq. 15l, the standard deviation of the number of channels on a link for the example network 200 of FIG. 2 having N=100 nodes and L=171 links ( δ =3.4 and h =6.1) is estimated to be σ(W o )≦12. Recall the mean number of channels on a link was estimated to be (W o )≅178 for this network. Again using Eq. 15l, the standard deviation of the number of channels on a link for the example network 200 of FIG. 2 having network of N=25 nodes and L=42 links ( δ =3.4 and h =3.0) is estimated to be σ W o ≅3.8. The mean number of channels on a link was estimated to be W o ≅22 in this case. [0102] In the above consideration of the variation of W o , the inventor recognizes that usually when traffic is routed and the network is optimized, paths are selected based on criteria such as the minimum number of hops, the shortest distance, or more generally the minimum cost. However, routing solutions that may be proven to be optimal are possible only for relatively small networks and, therefore, additional heuristic constraints are often imposed as strategies to ensure low cost. To minimize the cost of survivable networks, for example, algorithms to balance the traffic among the links are often introduced. By its definition, load-balancing deliberately seeks to dampen the variation of the number of channels carried on a link. Clearly if load-balancing is effective then the selection of paths from among the hop-degenerate routes is not random and σ(W o ) should be reduced relative to the value specified by equation (15l) above. As a corollary, the ratio of the achieved variance to the value obtained for random routing is a measure of the success of the load-balancing algorithm. [0103] The variance of the number of channels carried on a link derived above is a network global expectation based on routing decisions. A local view of the variations and the number of channels carried on a particular link (i,j) and their relationship to the terminating traffic and degrees of the local nodes may also be considered. A form for W ij based on equation (15b) and an heuristic argument based upon the routed traffic may be developed. Equation (15b) may be written to identify the local traffic terminating at the nodes connected to the link (both ends) and the through traffic that passes by both nodes according to equation (15r), which follows: W o =2 d / δ + d ( h −2)/ δ .  (15r) The first term corresponds to the division of the terminating traffic among the various links connected to the terminating nodes. Assuming minimum hop routing, to a good approximation the terminating traffic is equally distributed among all the links connected to the node. This implies a direct correlation of the first term of equation (15r) to the local degrees of nodes connected to the link. The second term, however, corresponds to the many channels traversing the link that have destinations distributed across the entire network. For the moment it is considered that the traffic is routed to minimize the number of hops, but otherwise no preference among the individual links is imposed. Under these circumstances it is hypothesized that the second term has negligible correlation to the local degrees of nodes and is best described by a combination of the mean value and variations randomly distributed across the network. Therefore, the number of channels on a link may be characterized according to equations (15s) and (15t), which follow: W ij =W B/E +W B/T   (15s) with W B/E ≡d i (1/δ i +1/δ j )−1.  (15t) (The right most “−1” in equation (15t) ensures the proper accounting of the demand between node i and node j.) The variable W B/T includes random variations in the number of through channels and satisfies equation (15u), which follows: W B/T ≡ d ( h −2)/ δ +1.  (15u) The variance of W B/T may be estimated using the statistical formalism described above with respect to equation (15l) with W B/T replacing W o and W B/T replacing W o . [0108] It can be verified by direct computation that the expectation value of W i,j (equations 15s-15u) yields W o (equation 15r) in the case of location-independent demand, as required. As the second term of equation 15r is locally uncorrelated with the first term, the variance of W o may therefore be expressed according to equation (15v), which follows: σ 2 ( W o )≅(2/ δ ) 2 σ 2 ( d )+ d 2 σ 2 (1/δ)+σ 2 ( W W/T )  (15v) The variance associated with routing decisions implicitly assuming no variation in δ has already been estimated using equation (15l). Now, the relative size of the variance in W o attributable to variations in the degrees of the nodes may also be estimated. The variations correlated to the local degrees of nodes (i.e., the second term of equation (15v)), may be computed directly from the network graph. For the present it should be noted that for uniform demand σ 2 (d)≡0, and σ( W B/E )/ W B/E ≅{square root}{square root over ([ δ n 1/δ n −1]/2)}.  (15w) Using equations (15t) and (15w), the mean and standard deviation of the number of A/D channels terminating at the two ends of a link are estimated to be W B/E ≅58 and σ(W B/E )≦13, respectively, for the example network 200 of FIG. 2 having N=100 nodes and L=171 links ( δ =3.4, h ≅6.1, 1/δ =0.32). The mean number of channels not terminating at either end of a link is approximately W B/T ≅120 for this network. For the smaller example network having N=25 nodes and L=42 links ( δ =3.4, h ≅3.0, 1/δ =0.32) the mean and standard deviation of the number of A/D channels terminating at the two ends of a link are estimated to be W B/E ≅14 and σ(W B/E )≦2.8. The mean number of channels not terminating at either end of a link is approximately W B/T ≅7.5 for this example. [0111] If the terminating demands are not uniformly distributed, but instead randomly distributed, then the first term in equation (15v) proportional to σ 2 (d) (i.e., σ d 2 (W o )) also contributes to the variance of W o according to equation (15x), which follows: σ d ( W o )/ W o =[2/ h ][(σ( d )/ d ].  (15x) As previously stated, the expressions for W o (equations (15b) and (15c)) are exact and independent of the estimations of σ(W o ). Restoration Capacity [0114] The additional capacity added to links to ensure network survivability depends upon the types of failures considered, the restoration strategy strategy, and the blocking characteristics of the cross-connects used to redirect the affected traffic over alternate routes. For the purpose of architectural comparisons, network survivability is very often defined in relation to single link failures (i.e., the network is designed and minimally sufficient capacity is deployed to ensure the network can support the traffic and is survivable against all single link failures). As explained earlier, this implies the network has sufficient extra capacity to restore all of the simultaneously failed demands sharing the common failed link. Extra capacity is counted in units of additional channel-links and is most often reported as a fractional increase above the total number of channel-links for minimum hop routing. Using that convention, the average number of channels on a link including extra capacity for restoration may be characterized according to equation (16a), which follows: W κ ≡ W o (1+ κ ).  (16a) The superscript designation κ is introduced to W to indicate that the expression accounts for extra capacity for restoration. This expression is independent of the demand model. In considering the individual failure of all the δi+δj−1 links that are connected to the two nodes at the ends of link (i,j), the number of channels on an individual link (i,j) including the extra capacity for restoration is characterized according to equation (16b), which follows: W κ ij =W ij + W o κ ij ,  (16b) where W ij and W o are given by equations (15t)-(15v) and equation (15s), respectively. The mean value of this model for W κ ij yields equation (16a), as required. Below formulae are developed for κ and κ ij as functions of the input network variables. [0117] Precisely determining the amount of additional capacity requires a detailed network analysis and a non-trivial exercise for large mesh networks. Obtaining exact results for general mesh networks when the number of nodes is more than about 20 is presently not practical because of the magnitude and duration of the numerical computations. Thus, some form of heuristic algorithm for routing traffic and assigning restoration capacity is usually employed for large networks. [0118] In considering the extra capacity that must be deployed to ensure survivability against single link failures, a general inverse dependency upon the degree of the nodes is readily recognized and explained qualitatively. For example, a ring network (which by definition has an average degree of node equal to 2) with dedicated protection requires 100% extra capacity relative to the minimum capacity necessary to carry the traffic demand. As such, a qualitative relationship between the fractional increase in capacity on a link and the degree of the node to which the link is connected may be characterized according to equation (17a), which follows: κ˜1/(δ−1).  (17a) However, a strict interpretation of equation (17a) as an equality can under-predict by one-third or more the necessary extra capacity for planar mesh networks when δ is greater than 2. To assess the feasibility of using an analytic equation to model the extra capacity, we have fitted the extra capacity determined by detailed calculation and simulation of mesh networks with uniform demands for the case of strictly non-blocking cross-connects using the expression κ =( a−b )/( δ − b ),  (17b) where a and b are parameters to be determined semi-empirically. [0121] The results for the extra capacity for 8 mesh networks are considered and the condition is also imposed that κ =1 for δ =2. The mesh networks had numbers of nodes N in the range of 4≦N≦100, average degree of node in the range of 2.5≦ δ ≦4.5, and required an average extra capacity in the range of 0.4≦ κ ≦0.9. The constraint to describe the ring network exactly using equation (17b) requires a =2. The best value of b was then determined to be b=−0.4. Within the accuracy (σ≅±17%) of the fitted results, the functional form for the extra capacity may be characterized according to equation (17c), which follows: κ ≅2/ δ .  (17c) The form of equation (17c) for the required extra capacity in the case of single link failures suggests that only one-half of the links connected to a node in common with the failed link participate in carrying the rerouted traffic. This is understood qualitatively when it is considered that using the other one-half of the links would result in diverting the rerouted traffic further away from its intended destination and consequently over even longer paths, which may introduce increased signal impairments, such as longer latency and higher bit-error-rate, as well as the complexity of involving larger numbers of nodes. For completeness an expression is noted for the extra capacity on the individual links that results in the expectation value of the extra capacity given by equation (17c), which is characterized according to equations (17d) and (17e), which follow: κ ij = 1 2 ⁡ [ 2 / δ j + 2 / δ j ] ⁢   ⁢ and ( 17 ⁢ d ) 〈 κ 〉 ≡ 1 L ⁢ ∑ i , j L ⁢ κ i , j ≅ 1 L ⁢ ∑ i , j L ⁢ ( 1 δ i + 1 δ j ) = 1 L ⁢ ∑ n M ⁢ ∑ κ δ n ⁢ 1 δ n = N L = 2 〈 δ 〉 ( 17 ⁢ e ) or more explicitly κ l =2/ δ n . It should be noted however, that based on equation (17e), the property that 1/δ l =1/ δ n . However, in general, 1/δ n ≠1/ δ n except for in regular networks of constant degree, δ, or as an approximation. [0124] A slightly more accurate semi-empirical representation (σ≅±12%) of the values of the extra capacities of the networks considered is characterized according to equations (17f) and (17g), which follow: κ l = 2/δ n ,  (17f) for which the corresponding local extra capacity is κ ij =½[(2/δ i ) 2 +(2/δ j ) 2 ]/[2/ δ ].  (17g) In both cases it is clear there is a strong correlation between the efficient use of spare capacity for survivability and the degrees of the nodes. Note too that the success of equations (17c)-(17g) in representing the required extra capacity also reinforces the postulation that the traffic load is relatively balanced on the individual links (i.e., equation (15b). It is also expected that the approximate analytic expressions for κ (e.g., equations (17)) hold independent of the demand model, as they were hypothesized based on the mesh topology of the network, and not explicitly upon the demand model. Finally, it is pointed out that the additional capacity required for dynamic networks, such as for survivable networks, will be larger if the cross-connects are not strictly non-blocking. For example, in the case of wavelength-division-multiplexed line systems and cross-connects without wavelength interchange except at the terminations, the increase of the extra capacity for restoration above the minimum value for strictly non-blocking cross-connects is typically in the range of only 5-20%, although the management complexity is greatly increased. [0127] For the example network 200 of FIG. 2 having N=100 nodes and L=171 links ( δ =3.4), the mean value of the extra capacity to ensure survivability under single link failures is estimated to be κ ≅0.58. As the mean degree of node for the second example network having N=25 nodes and L=42 links is nearly identical to that of the larger network by design, δ ≅3.4, the estimate for the mean value of the extra capacity to ensure survivability under single link failures is also nearly the same at κ ≅0.60. [0128] As described above, the extra capacity on individual links has been modeled in a manner that is both intuitive and consistent with empirical observations of the total extra capacity. The model for {κ} depends only upon the degrees of the nodes, {δ}, and consequently it is a function of the input network graph G, as stated explicitly in equation (13a). [heading-0129] Traffic on Link [0130] The average traffic carried on a link β is the product of the average number of demands on a link W and the termination-to-termination traffic per demand τ, and is characterized according to equation (18a), which follows: β ≡ W τ=τ h D/L = h T/L.   (18a) This direct proportionality is independent of the demand model. [0132] FIG. 5 graphically depicts a plot of the mean traffic on a link including idle restoration channels for uniform demand as a function of the number of nodes N and total network traffic T. In FIG. 5 , the mean traffic on a link β κ (N, T) for uniform demand with restoration is graphed as a function of the number of nodes N and total two-way traffic under the constraint δ =3.5 using a contour plot. [0133] For the example network 200 of FIG. 2 having N=100 nodes, L=171 links, and T=5 Tb/s, the mean value of the traffic carried on a link including extra capacity for restoration is β κ ≅284 Gb/s. In comparison, the mean value of the traffic carried on a link including extra capacity for restoration for the smaller example network having N=25 nodes, L=42 links, and T=1 Tb/s, is β κ ≅16 Gb/s. [0134] Based on the preceding discussions, the inventor determined that the variance of β is determined by the variance of W and that the variances are related according to equation (18b), which follows: σ(β)/ β =σ( W )/ W .  (18b) Number of Ports and Capacity of a Cross-Connect [0136] Among the key attributes of cross-connects are the port count, P, and total capacity, χ. The average number of ports on a cross-connect in a mesh network can be determined by counting the number of ports that each demand occupies as it traverses the network, tallying the number of ports for all demands, and then dividing by the number of cross-connects. By design a cross-connect—of which an add-drop multiplexer is considered a special case—is placed at each node of the backbone network to manage transport bandwidth, and so the number of cross-connects is given by the number of nodes, N. [0137] As illustrated in FIG. 3 , the number of output ports is usually equal to the number of inputs. Also, a P×P cross-connect, which has P inputs and P outputs (or P I/O ports), supports connections among P two-way channels. [0138] The average number of one-way input ports, P 1 is first calculated. FIG. 6 depicts a high level block diagram of two cross-connect ports 610 , 620 and the relationship among the local ADD, DROP and THRU channels. FIG. 6 illustratively serves as a guide to counting the number of cross-connect ports occupied by a demand as it traverses a network. In FIG. 6 , the numbers of add and drop demands, depicted as N−1, specifically correspond to the uniform demand model. Referring to FIG. 6 , consider a directed demand that enters, or is added to, the network via the cross-connect of the node on the left. Adding the demand requires one input port. Eventually, this demand exits the network. Dropping from the network is accomplished by entering and exiting the cross-connect at the destination node, which may be considered the node on the right of FIG. 6 . Thus, dropping the demand also requires one input port. Additionally, in traversing the network the demand under consideration occupies input ports at the cross-connects of the intervening nodes. Having defined “h” as the number of inter-terminal hops, the number of intervening cross-connects that the demand enters is h−1. Consequently, the number of input ports that a one-way demand occupies may be characterized according to equation (19a), which follows: p ij =1+1+( h ij −1)= 1+h ij .  (19a) The total number of input ports occupied by all demands is therefore characterized according to equation (19b), which follows: P t = ∑ i , j D 1 ⁢ [ 1 + h i , j ] = D 1 D 1 ⁢ ∑ i , j D 1 ⁢ [ 1 + h i , j ] = D 1 ⁢ 〈 1 + h i , j 〉 = N ⁢ 〈 d 〉 ⁡ [ 1 + ⁣ 〈 h 〉 ] , ( 19 ⁢ b ) and the average number of input ports P 1 occupied on a cross-connect at a node is characterized according to equation (19c), which follows: P 1 =( D 1 /N )[1+ h ]= d [1+ h ].  (19c) Equations (19a)-(19c) are valid independent of the demand model; while as before the value of h is implicitly dependent upon the demand model. For the case of a mesh network with uniform demands, d in equation (19c) is substituted using equation (11c) to obtain equation (19d), which follows: P 1 =( N− 1)[1+ h ],  (19d) where h may be approximated using equation (14b) or equation (14c). [0143] For completeness, the average number of two-way ports for a cross-connect of the same network is computed. The number of two-way terminations for a two-way demand is 2, one at each terminus. The average number of two-way thru ports occupied is 2[1+ h ] and the total number of two-way ports occupied is characterized according to equation (19e), which follows: P t = ∑ i < j D 2 ⁢ [ 1 + h i , j ] = D 2 D 2 ⁢ ∑ 2 i < j D 2 ⁡ [ 1 + h i , j ] = 2 ⁢ D 2 ⁢ 〈 1 + h i , j 〉 = 2 ⁢   ⁢ D 2 ⁡ [ 1 + ⁣ 〈 h 〉 ] . ( 19 ⁢ e ) Thus, the average number of two-way ports is characterized according to equation (19f), which follows: P 2 =2( D 2 /N )[1+ h ].  (19f) By substituting for D 2 using equation (10c), the inventor has determined equation (20a), which follows: P ≡ P 2 = P 1 ,  (20a) which may be appreciated by again considering FIG. 3 . This result is independent of the demand model and may also be structured to explicitly indicate the add, drop and through ports. Considering FIG. 6 and equation (20a) above, the inventor proposes equation (20b), which follows: P ≡ P ADD + P DROP + P THRU   (20b) where P ADD = P DROP = d   (20c) and P THRU = d ( h− 1)  (20d) and as such, P ADD + P DROP =2 d .  (20e) As previously stated, every demand occupies both a termination-side port and line-side port on each of the two cross-connects at the opposite ends of the demand. Another common partitioning of ports is between termination-side ports and line-side ports. In this case equation (20b) is rewritten according to equation (20f), which follows: P ≡ P TERM + P LINE   (20f) where P TERM = P ADD = d   (20g) and P LINE = P DROP + P THRU = d h .  (20h) [0153] In the above analysis for the average number of ports, the extra transmission capacity and extra cross-connect ports that are required for network survivability were introduced. As discussed earlier, for single-link failure scenarios, the link or line-side capacity is increased by the fraction <κ>. Thus, the total number of cross-connect ports for shared line-side restoration of mesh networks is obtained by introducing the extra capacity factor into equations (20h) and ( 19 c ), which results in equation (21 a), which follows: P κ = d [1+(1+ κ ) h ].  (21 a) The same result is also obtained considering that the total number of ports is the sum of the number of channels carried on each of the links connected to the node and the number of channels terminating at the node. The former is given by the product of W o and δ, and therefore yields equation (21b), which follows: P κ = d + W o (1+ κ ) δ .  (21b) Using equations (13b) and (15b) and the definition of κ it can be determined and illustrated that equation (21b) equates to equation (21a). [0156] To appreciate how P scales with the number of nodes, equations (21) may be considered for uniform traffic in the limit when N is large compared to 1. In that limit and using equations (11c), (14c) and (17c) for d , h and κ , respectively, equation (21b) may be rewritten according to equation (22a), which follows: P κ ≈[(1+2/ δ )/{square root} δ ] N 3/2 .  (22a) For networks with δ in the range of 3≦ δ ≦4, the term in equation (21b) dependent upon δ is within 14% of unity and for δ =3.5, the coefficient differs from 1 by less than 5%. Consequently, equation (22a) may be rewritten according to equation (22b), which follows: P κ N 3/2 .  (22b) Thus, if the number of nodes in the network is approximately 24, then the average number of ports required is about 125. When N is about 100, then P κ ˜3000. Similarly, the average traffic cross-section carried on the route between adjacent nodes is characterized according to equation (23), which follows: W κ ≈ N 3/2 / δ   (23) when N is large compared to unity. [0160] The average traffic handled by a cross-connect χ , measured in bits/second for example, is now computed straightforwardly from the average number of ports P and the communication bandwidth, either τ or B, associated with the basic unit of demand. Of course the former corresponds to the case when the channel utilization is 100% and the latter may correspond to a particular system increment or industry standard. Thus the average traffic handled by a cross-connect χ may be characterized according to equation (24a), which follows: χ(τ) ≡ P τ  (24a) or χ( B ) >≡ P B.   (24b) These direct proportionalities are independent of the demand model. [0163] For the example network 200 of FIG. 2 having N=100 nodes and L= 171 links, the mean number of ports on a cross-connect including ports for restoration is estimated to be P κ ≅1061. The corresponding mean cross-connect traffic is 1072 Gb/s. For the smaller example network having N=25 nodes and L=42 links, the mean number of ports on a cross-connect including ports for restoration is estimated to be P κ ≅141. The corresponding mean cross-connect traffic is 469 Gb/s. [0164] To compute the variance of the number of ports, P, the number of ports required for the individual nodes must be determined. In the preceding sections, expressions for the number of channels on the individual links have been formulated; namely equations (15d-15g), equation (16b), and equation (17d). Consequently, it is necessary only to add the termination side channels to the sum of the channels on the δ i links connected to an individual node i to obtain the sum of the ports, P κ i . Such an expression may be characterized according to equation (25a), which follows: P i κ = d i + ∑ j δ i ⁢ W ij κ . ( 25 ⁢ a ) Hence, the variance of P κ may be computed using this expression and the definition of the variance, equation (13d). In the spirit of clarifying the dependencies of the variance of P κ , the following illustrates an example where the local extra capacity for restoration is specified by equation (17d). In this scenario the number of ports on a local cross-connect is characterized according to equation (26a), which follows: P κ i ≅2 d i +[d i / δ + W B/T + W o / δ ]δ i + W o ,  (26a) where for the total extra capacity associated with ports at node i, the approximation in equation (26b), which follows, was used: κ i = ∑ j δ i ⁢ κ ij ≅ 1 + δ i 〈 δ 〉 . ( 26 ⁢ b ) [0167] Considering equation (26a), it is observed that there is a correlation between P κ i and δ i that is moderated by the variations in W T . The variance of P κ for uniform demand is characterized according to equation (27a), which follows: σ 2 ( P κ )≅[ d / δ + W B/T + W o / δ ] 2 σ 2 (δ)+ δ 2 σ 2 ( W T )  (27a) and the total number of ports, P κ is characterized according to equation (27b), which follows: P κ i ≅2 d i +[d i / δ + W B/T ]δ i + W o δ /δ i + W o δ 1/δ .  (27b) In this case there is a contribution to the number of ports from the extra capacity (1/δ i ) that is anti-correlated with the main term that is proportional to δ i . Thus, it is expected that the variance of P κ in this scenario for the extra capacity, equation (17g), to be somewhat less than the variance obtained using the first form, equation (17d). To illustrate this behavior it was assumed that the variance of W T is small and may be neglected. In this situation the standard deviation for the number ports for both scenarios (equations (17d) and (17g)) for the extra restoration capacity on a link for uniform demand may be characterized according to equations (28a) and (28b), respectively, which follow: σ( P κ )= W o (1+2/ δ )σ(δ)  (28a) and σ( P κ )= W o σ(δ)  (28b) It is evident from the equations above that the standard deviation corresponding to the second form of the local extra capacity, which more strongly varies with the local degree of the node, is smaller by a factor of 1/(1+2/ δ ). This is understood considering that nodes with smaller degree require larger extra capacity on connecting links and nodes with larger degree require less extra capacity on connecting links. As a result of this anti-correlation the distribution of the required ports is narrowed. [0172] For the example network 200 of FIG. 2 having N=100 nodes and L=171 links the mean and standard deviation of the degree of nodes is δ =3.4 and σ(δ)=1.1. Consequently, the standard deviation of the number of ports on a cross-connect based on the variance of the degrees of nodes is estimated to be σ(P κ )≅307 and σ(P κ )≅194 using equation (28a) and equation (28b), respectively. Recall the mean number of ports including restoration capacity was estimated to be P κ ≅1061. It is expected that the fractional deviations for the smaller example network having N=25 Nodes and L=42 links will be similar, as the statistics of the degrees of nodes are nearly the same by design. Again using equation (28a) and equation (28b), the standard deviation of the number of ports on a cross-connect for this smaller network is estimated to be σ(P κ )≅38 and σ(P κ )≅24, respectively. Recall that the mean number of ports including restoration capacity was estimated to be (P κ )≅141. [0173] In summary, in this and the preceding section it has been shown that the network global expectation model may be used to understand and predict the mean and variability of the number channels carried on links and present at the nodes, including the effects resulting from network survivability. It will be appreciate by one skilled in the relevant art informed by the teachings of the presenting invention that although the model has been illustratively applied to the case of uniform, location-independent, or random demand in this section on the variance of the number of ports, the methodology is directly applicable to other demand profiles. [heading-0174] Percentage Add/Drop [0175] Another important characteristic of the network is the percentage of add and drop traffic at a node. Referring to FIG. 6 and the one-way input ports on the cross-connect, it is observed that the average number of input ports occupied by traffic being either added or dropped at the node may be characterized according to equation (29a), which follows: P ADD + P DROP = D 1 /N+D 1 /N= 2 D 1 /N   (29a) The average number input ports occupied by traffic passing through the node may be characterized according to equation (29b), which follows: P THRU = D 1 ( h −1)/ N.   (29b) By definition the average ratio of the number of local add/drop ports to local total ports may be characterized according to equation (30a), which follows: 〈 ρ 〉 ≡ 1 N ⁢ ∑ n N ⁢ ( P ADD + P DROP ) n / P n , ( 30 ⁢ a ) which may be computed by substituting expressions for both the numerator and the denominator. However, another practical and useful definition of the add/drop ratio average is the ratio of the network total number of add/drop ports to network total ports. In this second case the ratio may be characterized according to equation (30b), which follows: ρ′ = N ( P ADD + P DROP )/ N ( P ADD + P DROP + P THRU )=( P ADD + P DROP )/ P   (30b) and therefore ρ′ =2/[1+ h ].  (30c) It should be noted that this relationship between ρ′ and h has been derived without reference to a model for the demands D 1 . Consequently, it is a general result and not restricted to the case of uniform demands. [0181] If the extra capacity for line-side restoration is accounted for, then the ratio average, ρ′ κ , of the number of add/drop ports to total ports (equations 21) may be characterized according to equation (30d), which follows: ρ′ κ =2/[1+(1+ κ ) h ].  (30d) The estimated add/drop ratios for the example network 200 of FIG. 2 having N=100 nodes and L=171 links without and with extra capacity for restoration are ρ ≅0.28 and ρ′ κ =0.19 using equation (30c) and equation (30d), respectively. In comparison, the estimated add/drop ratios for the example network having N=25 nodes and L=42 links without and with extra capacity for restoration are ρ′ ≅0.49 through ρ′ κ ≅0.34 using equation (30c) and equation (30d), respectively. This trend of increasing the fraction of through traffic as the number of nodes is increased is a general characteristic of a single-tier network with uniform demand. In the limit when N is large compared to 1 and the average degree of node is in the range 3≦ δ ≦4 the total number of ports is given by equation (22b) and the add/drop ratio average may be characterized according to equation (30e), which follows: ρ′ κ ≈2 /{square root}N.   (30e) Thus, for a mesh network of 25 nodes with shared line-side protection the ratio of add/drop to through channels is approximately 40% on average, and the percentage decreases as the number of nodes increases. Of course, this estimate is for the average node, and the percentage for a particular node can be larger or smaller depending upon the details of the network demand and topology. The use of shared termination-side protection will tend to increase the add/drop ratio. [0184] On a separate note related to the add/drop ratio, it is also worth pointing out that equation (30c) may be inverted to express h as a function of ρ′ , according to equation (31), which follows: h =[2/ ρ′ −1].  (31) Like equation (30c), equation (31) is a general result and not a function of the demand model. [0186] The ratio of the add/drop traffic to total traffic for an individual note may be formulated using equations (25) and (29a). For example, considering the case when σ(W T ) is negligible, the result using equation (17d) for the extra capacity may be characterized according to equation (32a), which follows: ρ i κ = 2 ⁢ 〈 d 〉 P i κ = 2 1 + ( 1 + 2 〈 δ 〉 ) ⁢ 〈 d 〉 δ ⁢ δ i 〈 d 〉 . ( 32 ⁢ a ) When N is large compared to 1 and δ is in the range of 3≦ δ ≦4, equation (32a) may be approximated according to equation (32b), which follows: ρ κ l ≈(2 /{square root}N )[ δ 3/2 /(1+2/ δ )](1/δ i )  (32b) and so in this case σ(ρ κ )/ ρ κ ≈σ(1/δ)/ 1/δ .  (32c) Also, ρ κ min/max / ρ κ ≈ δ /δ max/min   (32d) Thus, given that δ i may range from 2 to 8, it may be concluded that the add/drop ratio can conceivably range from ½ to 2 times the mean value. Network Cost [0192] In the previous section expectation values have been derived for the quantities of key network elements and network element subsystems required to carry out a basic cost analysis for a transport network. In this section the concept of the cost structure of network elements in relation to both the network elements and network element subsystems will be introduced. With an assumed cost structure, the total cost of the network as well as categories of costs may be computed, such as for transmission and bandwidth management. It is also illustrated by example how the network costs are compared using different combinations of technology, such as electronic and optical bandwidth management, using the network global expectation model. [0193] For the purpose of outlining the general principles of computing network costs using the network global expectation model, rudimentary cost structures are considered for the optical line system (OLS), electronic and cross-connect (EXC), and optical cross-connect (OXC). FIG. 7 depicts a high level block diagram of an exemplary architecture of OLS 710 , EXC 720 , and OXC 730 systems from a perspective near a node. In FIG. 7 , termination-side traffic enters the network at a node Via the EXC 720 where it is groomed (i.e., switched and multiplexed, into the fundamental units of inter-terminal bandwidth destined for specific nodes of the network). The groomed output channels from the EXC 720 then enter the OXC 730 , where they are directed to line systems placed along the inter-terminal links of the network according to the traffic routing scheme determined by either a centralized or distributed management system. In the architecture considered in FIG. 7 , the interfaces between network elements are illustratively optical translators (OTs), which ensure that the cost comparisons are under conditions of fixed network capability (features) and network performance. [heading-0194] Transmission Cost Structure [0195] A cost structure often used for optical fiber transmission is the average cost of transporting bandwidth (B) over distance (s). Herein this cost structure is represented as a cost coefficient, which is denoted as γ B-s . The units of γ B-s are dollars per gigabit per second per kilometer ($/Gbps/km). According to Gawrys, an approximate value for network transmission cost of a two-way channel may be characterized according to equation (33), which follows: γ B-s ≈$30 /Gbps/km   (33) based on historical data and projections. [0197] Considering this cost structure, the individual and mean cost of a transmission link of a survivable mesh network may be characterized according to equations (34a) and (34b), respectively, which follow: C i =γ B-s βs i ,  (34a) and c 1 =γ B-s β s ≅γ B-s β s ,  (34b) where for the model of uniform demand under present consideration β is given by equation (16) with κ given by equation (17c) and s is the expectation value of the link length. The expectation value of the link length, s , may be characterized according to equation (35a), which follows: 〈 s 〉 = 1 L ⁢ ∑ l L ⁢ s l , ( 35 ⁢ a ) where the set {s} are the physical lengths of the individual links. If the link lengths are known, then the expectation value s is quickly computed. Here, for the purposes of illustration, without introducing a specific set of link lengths, it is noted that for two-dimensional mesh networks the average link length scales inversely with the square-root of the number of nodes and is proportional to the square-root of the geographic area covered by the network. Thus, the expectation value of the link length, s , may be characterized according to equation (35b), which follows: s ≅{square root} A /({square root} N− 1).  (35b) The total cost of transmission is characterized according to equation (36a), which follows: C TRANS =L c 1 .  (36a) wherein it should be clear that C TRANS is an analytic function of only the independent input network variables (N, the number of nodes; L, the number of links; T, the total ingress/egress traffic; and A, the geographic area covered by the network), and so is easily computed. Consequently, when N is large compared to 1 and δ is in the range of 3≦ δ 4, C TRANS may be approximated according to equation (36b), which follows: C TRANS ≈γ B-s T{square root}A.   (36b) [0203] Currently, the yearly time averaged traffic carried by a combined voice and data backbone network in the continental United States is approximately 1 Tb/s. the daily and annual peak traffic load that the network must support is estimated to be ˜5× the average traffic. Thus, as an example we consider T=5 Tb/s. The geographic area of the continental U.S. is approximately A=8×10 6 km 2 . Thus, the approximate cost of transmission system equipment C TRANS to support the present traffic is approximately $400M. [0204] The approximate cost of transmission represented by equation (36b) is obviously an over simplification as it contains no dependency on the number of links. That behavior is not because of a shortcoming of the global network expectation model, but rather is attributed to our assumption of the cost structure, equations (33) and (34). Clearly a more realistic model of the cost structure for the link should include an explicit dependency upon the cost of optical fiber cable, the cost of end terminals, the cost of OTs, the cost of amplifiers, and the cost of amplifier pumps, for example. Realizing this, a refined cost structure for a link is characterized according to equation (37a), which follows: c i =γ t0 +γ t1 τW i +γ t2 s i +γ t3 τW i s i .  (37a) The expectation value for the cost of a link may then be characterized according to equation (37b), which follows: 〈 c 1 〉 = 1 L ⁢ ∑ i L ⁢ c i = 1 L ⁢ ∑ i L ⁢ { γ t0 + γ t1 ⁢ τ ⁢   ⁢ W i + γ t2 ⁢ s i + γ t3 ⁢ τ ⁢   ⁢ W i ⁢ s i } , ( 37 ⁢ b ) where the first term containing γ t0 reflects fixed costs for a link, such as the cost of the terminal equipment bays; the second term containing γ t1 includes costs that depend directly upon the number of channels carried, such as the number of OTs, the third term containing γ t2 includes costs that depend upon the distance traversed, such as the cost of trenching, cost of fiber, and the cost of amplifiers; and the fourth term containing γ t3 includes contributions that grow as the product of distance and wavelength, such as the cost of growth pumps and premium for specialized high capacity, long-distance fiber (e.g., dispersion-managed cable). [0207] The total cost of transmission may then be characterized according to equation (37c), which follows: C TRANS =L c 1 = L{γ t0 +γ t1 τ W +γ t2 s +γ t3 τ W s }.  (37c) Of the expectation values contained in equations (37), all have been previously computed except for W s . As previously described, the number of channels on a link for the case of uniform demands is nearly independent of the particular link. Thus, W s = W s and the total cost of transmission may be characterized according to equation (37d), which follows: C TRANS ≅L {γ t0 +γ t1 τ W +γ t2 s +γ t3 τ W s }.  (37d) The above approximation is further validated when it is considered that under real world circumstances the coefficient γ t3 is small compared to the other coefficients and rarely are the optical line systems loaded to their maximum channel carrying capacity. In this case, to gain a better appreciation for how the total transmission cost depends upon the basic network variables, the last term is dropped. Upon substituting for the remaining expectation values in equation (37d), the cost of transmission may then be characterized according to equation (37e), which follows: C TRANS ( N, T )≅½[γ t0 +γ t2 δ N{square root}A /({square root} N− 1)+γ t1 [{square root}A (1+2)/ δ )/{square root}{square root over ( δ −1])} T.   (37e) Here, the fixed startup costs (i.e., those independent of the traffic carried T) are evident in the first term, which is proportional to N or L (L=N<δ>/2,equation (13b)). Bandwidth Management Architectures and Cost Structure Electronic Bandwidth Management Only [0213] The network global expectation model provides the flexibility and ease of implementation to compute the network element variables and total network costs for a wide range of network sizes, total traffic, and a variety of architectural options. Herein it is illustrated how the costs for two different models of bandwidth management at the network nodes may be constructed. First considered is the case when an electronic cross-connect is used for both sub-rate grooming and cross-connect functions. In this case the total cost of bandwidth management is the cost of the electronic cross-connect, as is characterized in equation (38), which follows: C BWM =C EXC .  (38) The total cost of the electronic cross-connects may be written in terms of the expectation value of the cost of the nodes according to equation (39a), which follows: C EXC = C EXC N,   (39a) which follows directly from equation (8). An estimate of the current cost of high-speed electronic switching engines may be characterized according to equation (39b), which follows: γ ep ≈$1 K/Gbps,   (39b) which corresponds to a cost structure of the local EXC characterized according to equation (39c), which follows: C EXC =γ ep χ(τ).  (39c) Making use of equation (24a), the corresponding expectation value may be characterized according to equation (39d), which follows: c EXC =γ ep χ(τ) =γ ep τ P .  (39d) Substituting for c EXC in equation (39a) and using equations (12a) and (21a), the value of C EXC may be characterized according to equation (39e), which follows: C EXC = c EXC N= 2γ ep T [(2+ κ ) h ].  (39e) A more refined form for the cost structure of the electronic cross-connect, or IP router, that includes a startup term and a growth term may also be constructed according to equation (39f), which follows: c EXC =γ e0 +γ e1 χ τ .  (39f) In this case C EXC ( N,T )= c EXC N=γ e0 N+ 2[(2+ κ ) h ]γ e1 T.   (39g) These expressions for costs are valid independent of the demand model. Electronic and Optical Bandwidth Management [0223] Here a single-tier model using both optical and electronic bandwidth management is considered. More specifically, all traffic passes through the optical layer cross-connect and additionally all terminating traffic also passes through an electronic fabric for the purpose of channel grooming. Such an architecture is attractive when the cost of an optical port is significantly less than the cost of an electronic port for a given data rate. The total cost for BWM is thus characterized according to equation (40), which follows: C BWM =C EXC +C OXC   (40) Cost of Electronic Ports for Termination-Side Traffic [0225] As before, it is assumed that the cost of the electronic switch consists of a startup term and a term proportional to the traffic handled. However, herein only the terminating traffic traverses the EXC. Thus the mean cost of an EXC is characterized according to equations (41a)-(41c), which follow: c EXC =γ e0 +γ e1 τ P ADD +P DROP =γ e0 +γ e1 2τ P ADD ,  (41a) which, using equation (12) for τ, may be rewritten as c EXC =γ e0 +4γ e1 T/N.   (41b) Consequently, C EXC =γ e0 N+ 4γ e1 T.   (41c) Cost of Optical Ports for Thru and Add/Drop Traffic [0229] The total cost of OXCs using the network global expectation formalism may be characterized according to equation (42a), which follows: C OXC = c OXC N.   (42a) An estimate of the current cost of high-speed optical switching engines may be characterized according to equation (42b), which follows: γ op ≈$2.5 K /port.  (42b) Based on this cost structure and the architecture under consideration, which specifies that both through and termination-side traffic pass through the OXCs, the individual and mean OXC costs may be characterized according to equations (42c) and (42d), which follow: c oxc =γ op P,   (42c) and so c oxc =γ op P .  (42d) Substituting variables to obtain an expression that is independent of the demand model, the total cost of the OXCs may be characterized according to equation (42e), which follows: C OXC ( N )= c oxc N =2γ op D ( N )[(2+ κ ) h ],  (42e) where D(N) is the number of two-way demands. [0235] As in the other examples, a cost structure for the optical cross-connect consisting of a startup term and a growth term may also be considered and may be characterized according to equation (42f), which follows: c oxc =γ o0 +γ o1 P   (42f) In this case the mean and total cost of the OXCs may be characterized according to equations (42g) and ( 42 h ), which follow: c oxc =γ o0 +γ o1 P   (42g) and C OXC ( N )= c oxc N=γ o0 N+ 2γ 01 D ( N )[(2+ κ ) h ].  (42h) [0238] Summing the electronic and optical bandwidth management costs, results in equation (43), which follows: C BWM ( N,T )=(γ e0 +γ o0 ) N+ 4γ e1 T+ 2γ o1 D ( N )[(2+ κ ) h ].  (43) Comparison of Costs for Example Node Architectures [0240] As an illustration of the application of the network global expectation model, the total costs for BWM for the two single-tier node architecture examples just described; namely electronic plus optical BWM and electronic-only BWM, are compared as a function of the number of nodes N and traffic T for fixed mean degree of node. The results of the calculations using the coarse cost structures for the EXC and OXC costs, equations (39b) and (42b), are graphed in FIG. 8 . [0241] FIG. 8 graphically depicts a plot of the total cost of bandwidth management using the combination of optical and electronic cross-connects compared to the total cost of bandwidth management using only an electronic cross-connect. The ratio is plotted as a function of the number of nodes, N, and two-way traffic, T. In the case of the optical and electronic architecture, it is assumed that all traffic follows through the optical switch fabric and additionally that all terminating traffic flows through the electronic switch fabric. The calculations performed and depicted in FIG. 8 are for uniform demand with restoration under the constraint δ =3.5. The cost structure (γ) used for the optical cross-connects and electronic cross-connects for this example are $2.5 K/port and $1 K/Gbps, respectively. It should be noted that these costs structures and values are rudimentary, intended to be illustrative, and should not be interpreted as definitive. [0242] The network global expectation model of the present invention may be used to identify the region of the network parameter space where optical layer cross-connects may be introduced in conjunction with electronic cross-connects, or IP Routers, to economic advantage. The model accounts not only for the different characters of the cost structures as a function of traffic, but also accounts for the changing ratio of add/drop to through traffic as the number of nodes and links change. It is observed that for fixed values of the number of nodes for N greater than 15 that the total cost of bandwidth management using the electronic and optical (E&O) architecture decreases and becomes less than the cost of the electronic (E)-only solution as the total traffic increases. This is attributed to the assumption that the cost of an optical switch port is independent of channel bit-rate while the cost of an electronic switch port is directly proportional to the channel bit-rate. It is also observed that for fixed total network traffic that the cost of the E&O solution increases and becomes more expensive than the E-only solution as the number of nodes is increased and the mean degree of the nodes is held constant. This is because the mean termination-to-termination traffic decreases as the number of nodes is increased for fixed mean degree of the nodes (see FIG. 4 ), and consequently below some channel bit-rate, the fixed cost of an optical switch port becomes more expensive than an electronic switch port. [0243] Of course, the details of the cost crossover depend upon the particulars of the technology price points (cost structure and coefficients), and consequently, the graph of FIG. 8 is intended only to demonstrate the capabilities and possibilities of the global expectation model and not to make a definitive recommendation. It should be noted that herein it has been implicitly assumed via the cost structures that the respective cross-connects technologies are capable of providing the required switch and backplane capacities. In the absence of more refined cost structures that account for these limitations, other equations and graphs of the model may be used, such the total number of required ports (equation (21b)) or the mean cross-connect traffic, to identify regions of the network traffic-node space that are beyond the capabilities of a particular architecture or technology. [heading-0244] Total Network Costs [0245] The total network cost may be computed by summing the cost for transmission and bandwidth management using the formulae derived herein. For completeness equation 4 may be characterized according to equation (44), which follows: C T =C TRANS +C BWM   (44) [0246] Clearly, a useful attribute of the model is that the relative cost of transmission and bandwidth management can easily and quickly be determined. [0247] To illustrate the utility of the network global expectation model, FIG. 9 depicts a calculation of the total cost of a mesh network with uniform demand as a function of the number of nodes N and total traffic T. FIG. 9 graphically depicts a plot of the total cost of a mesh network with uniform demand as a function of the number of nodes N and total traffic T. The sum of transmission and bandwidth management equipment costs, C T (N,T), is graphed as a function of the number of nodes, N, and total two-way traffic, T using a contour plot. As in FIG. 8 , the calculations in FIG. 9 are for uniform demand with restoration under the constraint δ =3.5. The cost structures used for the optical line systems, electronic cross-connects, and optical cross-connects are $30/Gbps/km, $1 K/Gbps, and $2.5 K/port, respectively. Again, it should be noted that these cost structures and values are intended only to illustrate the capabilities and possibilities of the global expectation model of the present invention and should not be interpreted as definitive. [0248] The results of FIG. 9 are for the case where the nodal bandwidth manager consists of a combination of optical layer and electronic cross-connects and the geographic area corresponds to the continental U.S. In the accounting, equations (33) and (34), equations (39b) and (39c), and equations (42b) and (42c) were used for the cost structure of the transmission links, electronic cross-connects, and optical cross-connects, respectively. [0249] Among the features that may be observed by considering FIG. 9 is the impact of the cost of bandwidth management as the number of nodes increases. A qualitatively similar result is obtained for the case of electronic-only bandwidth management. Considering equation (22b) for total number of cross-connect ports and equation (30e) for the add/drop ratio, the large cost for large N may be interpreted to be a consequence of the single layer architecture. In effect, single-tier (flat) networks can not practically scale to very large number of nodes because as the number of nodes increases an increasing fraction of the traffic processed at each node is through traffic destined for other nodes. It is for this reason that the voice and packet networks are organized hierarchically based on geographic communities. [0250] The underlying phenomenon may also be the driving factor behind more broadly observed scaling behavior of networks and biological systems. Clearly there are performance and operational tradeoffs between single-tier and multi-tier networks, and network operators will adjust the number of nodes and architecture in the backbone depending upon the costs for transmission and bandwidth management; changing cross-connect, line-system, and technology price points; and the evolution of traffic demand. [heading-0251] Refinement of Cost Structure and Evolution of Network Cost [0252] In alternate embodiments of the present invention, the cost structure may be modified to account for the real-world implementation limits affecting maximum system capacities. Examples of such constraints are the maximum number of channels or wavelengths an optical line system is engineered for, or the maximum throughput of a switch fabric or backplane in the case of a cross-connect or router. Such hard bounds to network element capacity occur for any physical realization and have the effect of introducing quantum steps in the cost structure. When required capacities exceed the system capabilities, generally additional systems are deployed in parallel, and additional corresponding startup costs are incurred. Having developed a framework for the evaluation of the variances and distribution functions of key network variables earlier herein, a foundation has been provided to estimate the number of additional systems that are required given the network requirements and system bounds. Note too that in some instances the result of introducing these additional systems is to effectively increase the number of links or nodes of the network. [0253] Furthermore, in alternate embodiment of the present invention, the network global expectation model of the present invention may be used for sensitivity analyses of the dependency of requirements and costs upon primary and secondary network and network element variables. The network global expectation model may also be used to compute the constituent and total network costs as a function of time. This requires only a model for how the total network traffic, number of nodes and links, and technology costs are expected to change. Some models for estimating how the total network traffic, number of nodes and links, and technology costs are expected to change are known in the art. [0254] As previously mentioned, although the concepts of the present invention are being described herein with respect to communication networks, the concepts of the present invention may be applied to other networks and systems, such as power and commodity distribution and transportation systems. [0255] The operations of the present invention may be performed by a general purpose computer that is programmed to perform various operational calculations and functions in accordance with the present invention. In addition, the calculations and functions of the present invention can be implemented in hardware, for example, as an application specified integrated circuit (ASIC). As such, the process steps described herein are intended to be broadly interpreted as being equivalently performed manually by a user or by software, hardware, or a combination thereof. [0256] Furthermore, in an alternate embodiment of the present invention, the calculations, equations, and operations of the present invention herein may be loaded into the memory of a general purpose computer, along with instructions, for performing the operations and functions of the present invention. As such, the present invention comprises a computer program product. [0257] While the forgoing is directed to various embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. As such, the appropriate scope of the invention is to be determined according to the claims, which follow.
In the network global expectation model of the present invention, expectation values evaluated over the entire network are used as a multi-moment description of the required quantities of key network and network element (NE) resources and commensurate network costs. The network global expectation model of the present invention naturally and analytically connects the global (network) and local (network element) views of the communication system, and thereby may be used as a tool to gain insight and very quickly provide approximate results for the preliminary evaluation and design of dynamic networks. Further, the network global expectation model of the present invention may serve as a valuable guide in the areas of network element feature requirements, costs, sensitivity analyses, scaling performance, comparisons, product definition and application domains, and product and technology roadmapping.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "FIELD OF THE INVENTION [0001] This invention relates to the field of optical networks and more specifically, to rapidly quantifying the needs and costs of optical networks.", "BACKGROUND OF THE INVENTION [0002] The technology and architecture for circuit and packet communication networks continue to evolve, and converge.", "Fundamental to the comparison and selection of network architectures and their technological implementations is the total cost of ownership of the network.", "This cost includes the expenses for capital equipment (CAPEX), network operation (OPEX), and network management (MANEX).", "While operational and management expenses represent the largest share of the total cost of ownership, capital costs are a considerable and highly visible portion of the initial investment.", "Equipment cost is therefore a very important factor in the choice of architecture and technology.", "Therefore, a model for very quickly gauging the network equipment needs and costs is needed.", "SUMMARY OF THE INVENTION [0003] The present invention provides a network global expectation model for estimating the number of network elements, network elements characteristics, and costs of communication networks using analytic formulae.", "The network global expectation model includes the calculation of both the mean value and variance of all key network quantities and may be applied to a wide range of topologies, architectures, and demand profiles.", "[0004] The network global expectation model of the present invention uses expectation values as a multi-moment description of the required quantities of key network and network element (NE) resources and commensurate network costs.", "This approach naturally, analytically, and accurately connects the global (network) and local (network element) views of the communication system.", "As a result, the model may be used as a tool to gain insight and quickly provide approximate results for preliminary network evaluation and design, element feature requirements, costs, sensitivity analyses, scaling performance, comparisons, product definition and application domains, and product and technology road-mapping.", "[0005] The network global expectation model of the present invention is adaptable to both increasing and decreasing levels of detail and sophistication of the cost structures.", "Because of the analytic nature of the model the estimates of quantities may be computed much faster than is possible with detailed routing solvers, and so the model is ideally suited to network analyses in dynamic operating and technological environments.", "The uncomplicated and transparent accounting of network elements, systems, and costs inherent in the network global expectation model of the present invention constitutes a framework for the cooperative exchange of critical planning information on evolving network needs across the many sectors of the communication business.", "BRIEF DESCRIPTION OF THE DRAWINGS [0006] The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which: [0007] FIG. 1 depicts a high level abstract representation of a mesh network wherein an embodiment of the present invention may be applied;", "[0008] FIG. 2 depicts a high level representation of a prototypical backbone network wherein an embodiment of the present invention may be applied;", "[0009] FIG. 3 a depicts a high level block diagram of an exemplary cross-connect and line system arranged to illustrate five two-way ports (North, South, East, West, and Termination) service by a cross-connect wherein an embodiment of the present invention may be applied;", "[0010] FIG. 3 b depicts a high level block diagram of the system of FIG. 3 a arranged to illustrate five one-way ports (five inputs and five outputs);", "[0011] FIG. 4 graphically depicts a plot of the termination-to-termination traffic, τ, for uniform demand as a function of the number of nodes, N, and total network traffic, T. [0012] FIG. 5 graphically depicts a plot of the mean traffic on a link including idle restoration channels for uniform demand as a function of the number of nodes N and total network traffic T;", "[0013] FIG. 6 depicts a high level block diagram of two cross-connect ports and the relationship among the local ADD, DROP and THRU channels;", "[0014] FIG. 7 depicts a high level block diagram of an exemplary Bandwidth Management Architecture using both optical and electronic cross-connects;", "[0015] FIG. 8 graphically depicts an illustrative comparison of bandwidth management costs;", "and [0016] FIG. 9 graphically depicts a contour map of the total cost of a mesh network with uniform demand as a function of the number of nodes N and total traffic T. DETAILED DESCRIPTION OF THE INVENTION [0017] Although various embodiments of the present invention herein are being described with respect to various communication networks, such as backbone, fiber-optic transport networks and mesh networks, it should be noted that the specific communication networks are simply provided as exemplary environments wherein embodiments of the present invention may be applied and should not be treated as limiting the scope of the invention.", "It will be appreciated by those skilled in the art informed by the teachings of the present invention that the concepts of the present invention are applicable in substantially any network wherein it is desirable to quickly gauge the network equipment needs and costs.", "[0018] In the present invention, a general formalism of the global network expectation model is developed and application illustrated by considering single-tier backbone networks with location-independent traffic demands.", "While the methodology presented herein is very general, for specificity the application is described throughout the specification in the context of mesh networks.", "[0019] As the cost of a network for a specified set of features is considered the metric for comparison of architectures and technologies, the inventor proposes that the total network cost is exactly the sum of the costs of the constituent parts, or elements, of the network.", "This fundamental accounting of costs may be written mathematically according to equation one (1), which follows: C T ≡ ∑ i ⁢ c i , ( 1 ) where C T is the total network cost and c i is the unit cost of the ith component (herein and throughout this disclosure the symbolic notation Σ indicates the summation over the various contributing terms, in this case the many individual components.) [0021] It is usual that there are many components of a given type used throughout the network, and these identical parts share a common cost.", "In this case using the associative, commutative, and distributive properties of the field of real numbers, equation (1) above may be rewritten according to equation two (2), which follows: C T = ∑ i ⁢ v i ⁢ c i , ( 2 ) where again C T is the total network cost, v i is the number of network elements of type i, and c i is the corresponding unit cost of network element of type i. [0023] Without loss of generality it may be assumed that the technology and corresponding unit costs, c i , of the network elements used to construct the network are known, i.e., given apriori.", "The challenge of network design is to determine the number, v i , and placement of each of the network elements of the given types to minimize the total network cost under the constraint to service a specified traffic demand among the network terminations located at specific geographic locations.", "The strategy of the model of the present invention is to carefully estimate the products of the network element counts and respective costs while satisfying the external constraints, and thereby to estimate the total network cost using equation (2) above, but without explicitly establishing knowledge of the placement of every individual component within the network.", "[0024] The sum in equation (2) does not distinguish among the various categories of network elements, but considers each contributing type as atomic (i.e., indivisible).", "Without changing the value of the sum, terms may be collected that are logically related to one another into a cost subtotal for larger categories of elements.", "Denoting a general set of categories as α, equation (2) may be rewritten according to equation three (3), which follows: C T = ∑ α ⁢ ∑ i ⁢ v i ⁡ ( α ) ⁢ c i ⁡ ( α ) .", "( 3 ) One useful subdivision for separating costs is based on collecting the costs for signal transmission (TRANS) and signal bandwidth management (BWM) into separate terms.", "In this case equation (3) above may be rewritten according to equation four (4), which follows: C T = ∑ TRANS ⁢ v i ⁢ c i + ∑ BWM ⁢ v j ⁢ c j , ( 4 ) The transmission term might include, for example, objects such as optical transceivers (OT), optical multiplexers (OMUX), and optical amplifiers (OA).", "The bandwidth management term might include objects such as multi-service platforms (MSP), electronic cross-connects (EXC), optical add/drop multiplexers (OADM), and optical cross-connects (OXC).", "Of course, which objects are to be associated with particular categories is a matter of architectural choice.", "[0027] FIG. 1 depicts a high level abstract representation of a mesh network wherein an embodiment of the present invention may be applied.", "The mesh network 100 of FIG. 1 comprises a plurality of nodes (illustratively 6 nodes) 110 1 - 110 6 (collectively nodes 110 ), where traffic may enter and leave the mesh network 100 , a plurality of terminals (illustratively 6 terminals 115 1 - 115 6 ) (collectively terminals 115 ) connected to the nodes 110 , which are the sources and sinks of traffic in the network 100 , and a plurality of inter-nodal links (illustratively 9 links 120 1 - 120 9 ) (collectively links 120 ), which represent the physical segments over which the inter-terminal traffic may be carried, or transported, between the nodes 110 .", "The total number of nodes and links of the mesh network 100 of FIG. 1 are denoted by N and L, respectively.", "The average degree of node in the mesh network 100 of FIG. 1 is δ =3 for N=6 nodes and L=9 links.", "[0028] FIG. 2 depicts a map of the United States of America comprising an illustration of an exemplary mesh network, such as the mesh network 100 of FIG. 1 , wherein an embodiment of the present invention may be applied.", "FIG. 2 depicts a core fiber transport network typical of larger inter-exchange carriers of the continental United States.", "The example network 200 of FIG. 2 illustratively comprises 100 nodes and 171 links.", "The average degree node is δ =3.4, and the average number of minimum hops between node pairs is h =6.6.", "[0029] As suggested by the view of the mesh networks illustrated in FIG. 1 and FIG. 2 , the total network cost, C T , may also be represented by terms that correspond to the L links and N nodes of the network according to equation five (5) or equation six (6), which follow: C T = ∑ l L ⁢ c l + ∑ n N ⁢ c n , ⁢ or ( 5 ) C T = ∑ LINKS ⁢ c l + ∑ NODES ⁢ c n , ( 6 ) where c i is the cost of the lth link and c n is the cost of the nth node.", "If the first term of equation (5) above is multiplied by the factor L/L and the second term by N/N and note that the expectation value, q , or average, of a set of values {q i } i=1, m is defined according to equation seven (7), which follows: 〈 q 〉 = 1 m ⁢ ∑ i m ⁢ q i , ( 7 ) then equation (5) above may be rewritten according to equation eight (8), which follows: C T =L<c i >+N<c n >.", "(8) Thus, as expressed in Eq.", "8 the exact cost of the network may be considered as the sum of the expectation value of the cost of a link times the number of links and the expectation value of the cost of a node times the number of nodes.", "The global expectation values (c i ) and (c n ) are themselves explicitly defined according to equations (9a) and (9b), which follow: 〈 c l 〉 = ∑ i ⁢ 〈 v i 〉 l ⁢ c i , ⁢ and ( 9 ⁢ a ) 〈 c n 〉 = ∑ j ⁢ 〈 v j 〉 n ⁢ c j .", "( 9 ⁢ b ) Note, throughout this disclosure, the bracket notation, , will be used to denote the expectation value of a variable.", "In instances when the corresponding set {q} of an expectation value q may be ambiguous, the right bracket of the expectation value may be followed by a subscript to provide clarification.", "For example, in equation (9a) above, ν i l indicates an expectation value over the set of links {l} and in equation (9b) above, ν j n indicates an expectation value over the set of nodes {n}.", "Also regarding expectation values, here the elements q i of the set {q} are not samples of a variable associated with either a discrete or continuous probability distribution, but rather define a distribution.", "[0034] The relationship of network cost to link and node costs embodied in equations (8-9) above could have served as the starting point of this discussion, however, the inventor has decided to begin the discussion of the present invention instead using equation (1) to firmly establish that the use of expectation values, or averages, to determine the total network cost is not an approximation, but is exact.", "The approximations of the global expectation model(s) reside instead in the estimation of the expectation values of the quantities of network elements, ν .", "Consequently, the predictive capability of the model will depend upon the accuracy of the estimations of these mean values and the applicability of other related assumptions, such as the demand model.", "As will be demonstrated herein, for many variables the expectation values may be computed exactly from the input variables for a given demand model, while for other variables it is necessary to introduce semi-empirical approximations.", "[heading-0035] Network and Primary Model Variables [0036] Referring back to FIG. 1 and FIG. 2 , a communication network has been defined as the combination of a network graph, denoted G, consisting of a set of N nodes {n i } and set of L connecting two-way links, or edges, {l i }, and a network traffic.", "The network graph may be represented by the symmetric matrix [g] with elements g ij .", "The pair-wise communication traffic between nodes may be represented by the symmetric demand matrix [d] with elements d ij and the total ingress/egress traffic T. [0037] The matrix elements g ij are either 0 or 1 in value and specify whether a pair of nodes is connected via a physical link.", "The summation of all the values of the matrix elements of [g] yields the number of one-way links L 1 , which is twice the number of two-way links, L 2 .", "The demand matrix elements d ij are either 0 or a positive integer and denote the magnitude of the termination-to-termination traffic in quantized units of some basic measure of communication bandwidth, such as a standardized channel bit-rate, B. The summation of all the values of the matrix elements of [d] yields the number of one-way demands D 1 , which is twice the number of two-way demands D 2 .", "It should be noted that, generally the diagonal elements of [g] and [d] are zero.", "The demands are also often referred to as logical links.", "[0038] Often the channel bit-rate is not explicitly given for the network of interest.", "Instead, the total ingress/egress traffic T and number of demands are specified.", "In that case a value of the termination-to-termination τ traffic must be deduced, and from this a logical value of B may be chosen.", "It is for this reason that here the total two-way traffic is considered T 2 , which is one-half the total one-way traffic T 1 , to be an independent variable and for τ to be a dependent variable.", "Having chosen T as an independent variable, a complete set of model inputs is obtained, namely;", "G(N,L), D, and T together with a demand model.", "The inventor demonstrates herein that all other variables of interest may be derived from these variables.", "[0039] In counting quantities such as links, demands, traffic, etc.", "it is necessary to distinguish between one-way (simplex) and two-way (duplex) variables.", "As indicated above, the number of two-way links, demands, and traffic is one-half the corresponding number of one-way values.", "These relationships are illustrated in FIG. 3 a and FIG. 3 b (described below), and formally summarized according to equations (10a), (10b) and (10c), which follow: Links: L = L 2 = L 1 /2 (10a) Total Traffic: T = T 2 = T 1 /2 (10b) Total Demands: D = D 2 = D 1 /2 (10c) [0040] FIG. 3 a depicts a high level block diagram of an exemplary cross-connect and line system wherein an embodiment of the present invention may be applied.", "The cross-connect and line system 300 of FIG. 3 a illustratively comprises five two-way ports 310 - 314 (illustratively, North, South, East, West and Termination ports) serviced by the cross-connect 320 .", "[0041] FIG. 3 b depicts a high level block diagram of the cross-connect and line system 300 of FIG. 3 a arranged to illustrate five one-way ports 330 - 334 (five input ports and five output ports).", "It is typical to define a two-way channel of bandwidth B as the combination of two one-way channels, XY and YX, each of bandwidth B. That is the single value B describes both the one-way and two-way channels.", "This is evident in the examples depicted in FIG. 3 a and FIG. 3 b .", "Also, considering the trivial case of two nodes, N=2, and one two-way link, L=1, the total one-way traffic is T 1 =2B, and the total two-way traffic is T=T 2 =B.", "Of course, so long as one-way or two-way variables are used consistently, or the proper conversion is made, the results and conclusions are the same.", "For example, B=T 2 /D 2 =T 1 /D 1 .", "Referring back to FIG. 3 a and FIG. 3 b , it should be noted that the numbers of one-way and two-way ports are identical, i.e., P 1 =P 2 .", "Also, the channel bit-rate B, or alternatively the termination-to-termination traffic, τ, describes both the one-way and two-way traffic between terminating nodes.", "[0042] The output variables that are determined by the network global expectation model given the small number of inputs are many.", "Among them are the termination-to-termination traffic rate and expectation values and variances for the degree of node, number of hops, wavelengths on a link, traffic on a link, restoration capacity, number of ports on a cross-connect, total capacity of a cross-connect, and percentage add/drop at a node.", "With these expectation values and a cost model for the individual elements the total network cost may be computed.", "[heading-0043] Single-Tier Networks with Location-independent Demands [0044] To introduce the global expectation model a single-tier network consisting of a set of peer nodes and uniform, fully-connected inter-terminal demands is first considered.", "While this may seem restrictive, in fact the network global expectation model may be applied to a wide range of network topologies, architectures, and demand profiles.", "This will become evident as the expectation values and general relationships that are independent of the details of the topology, architecture, and demand are formulated and derived.", "Additionally, the specific results for uniform demand may also be useful in gauging key quantities for non-uniform demand profiles.", "For example, in the case of non-uniform demand that is not correlated with the absolute or relative location of terminal pairs (eg.", "random demand), uniform demand may be considered an average representation on the non-uniform demand.", "Also, one may envision restructuring an otherwise non-uniform network by grooming the traffic and truncating the set of nodes to produce a core network approaching the characteristics of a single-tier network with uniform demand.", "Having developed the general formalism here, in future works additional topologies, architectures, and profiles of interest will be explicitly considered.", "[0045] Most core networks carry symmetric traffic between nodes, and so working with two-way variables is the norm.", "However, in some instances visualizing and counting one-way variables may be more intuitive, such as tracking a one-way demand from source to destination.", "Of course following two-way demands from termination to termination is equivalent.", "In the following, expressions will be explicitly developed using both one-way and two-way input variables for utmost clarity.", "In very many cases the definition of output variables is such that the values do not change when switching between the one-way and two-way perspectives, as was previously illustrated.", "[0046] Throughout the following, the model of the present invention will be applied to estimate key characteristics of two example networks.", "The first example network is the network 200 depicted in FIG. 2 , which consists of 100 nodes and 171 links, uniform demand, and total two-way network traffic of 5 Tb/s.", "A second example network (not shown) is of similar topology and consists of 25 nodes and 42 links, uniform demand, and total two-way traffic of 1 Tb/s.", "[heading-0047] Number of Demands [0048] The number of nodes, N, the total two-way traffic, T, and number of two-way links, L, are inputs of the model.", "The traffic demand is also an input of the model.", "The total number of demands is explicitly and, of course, straightforwardly related to the numbers of demands terminating at the individual nodes.", "The one-way demands terminating at node i may be related to the elements of the demand matrix [d], viz.", "d i =Σ N d ij .", "Summing the terminating one-way demands, the total one-way and total two-way demands may be related to the mean number of terminating demands at a node, d n , according to equations (11a) and (11b), which follow: D 1 = ∑ i N ⁢ d j = N N ⁢ ∑ i N ⁢ d i = N ⁢ 〈 d 〉 n , ⁢ and ( 11 ⁢ a ) D ≡ D 2 = D 1 2 = 1 2 ⁢ N ⁢ 〈 d 〉 n .", "( 11 ⁢ b ) The above expressions in equations (11a) and (11b) are independent of the details of the demand model.", "The uniform demand model specifies that there is a one-way demand from every node to every other node, or a two-way demand between every node-node pair of the N nodes.", "Thus, the expression for uniform demand may be characterized according to equations (11c), (11d) and (11e), which follow: d n =N− 1 (11c) and D 1 =N ( N− 1) (11d) D≡D 2 =N ( N− 1)/2 (11e) Using the equations above, the number of two-way demands may be calculated for the two example networks described above.", "For example, the number of two-way demands (logical links) for the example network 200 of FIG. 2 having N=100 nodes and L=171 physical links is D=4,950.", "The number of two-way demands for the second example network described above having N=25 nodes and L=42 links is D=300.", "Termination-to-Termination Traffic [0053] The value of the termination-to-termination traffic, τ, can be computed exactly as the ratio of the total ingress/egress traffic, T, and total number of two-way network demands, D, terminating at all nodes.", "As such, the value of termination-to-termination traffic, τ, may be characterized according to equations (12a) and (12b), which follow: τ≡ T 1 /D 1 =T 2 /D 2 =T/D, (12a) and for uniform demand τ≡ T/[N ( N− 1)/2].", "(12b) The total traffic, T, and total number of demands, D, define the termination-to-termination traffic, τ, as indicated by the relationship expressed in Eq.", "12a, which is independent of the demand model.", "As the total traffic and the number of demands define the termination-to-termination traffic, τ, the value of τ is uniquely specified and as such its variance is exactly zero.", "[0056] FIG. 4 graphically depicts a plot of the termination-to-termination traffic, τ, for uniform demand as a function of the number of nodes, N, and total network traffic, T. In FIG. 4 , the termination-to-termination traffic, τ(N,T) for uniform demand is graphed as a function of the number of nodes, N, and total two-way traffic, T, using a contour plot.", "[0057] The termination-to-termination traffic, τ, for the example network 200 of FIG. 2 having N=100 nodes, L=171 links and total traffic of T=5 Tb/s is τ=1.01 Gb/s.", "This may be compared to τ=3.3 Gb/s for the example network having N=25 nodes, L=42 links, and total traffic of T=1 Tb/s.", "The channel bit-rate is smaller for the larger network because the number of demands for the larger network is significantly greater than for the smaller network.", "[heading-0058] Degree of Node [0059] The average degree of a node, δ , (i.e. δ n ), is calculated straightforwardly by summing the number of one-way (directed) links and dividing by the number of nodes.", "Referring back to the matrix representation [g] of the network graph of FIG. 1 and FIG. 2 , the average degree of node may be characterized according to equations (13a) and (13b), which follow: δ i = ∑ j N ⁢ g ij ⁢ ⁢ and ⁢ ⁢ so ( 13 ⁢ a ) 〈 δ 〉 = 1 N ⁢ ∑ i N ⁢ ∑ j N ⁢ g ij = L 1 N = 2 ⁢ L 2 N = 2 ⁢ L N .", "( 13 ⁢ b ) This compact expression for (δ) is exact and independent of the demand model.", "[0061] The variance σ 2 (q) and standard deviation σ(q) of the set of values for the network variable q, are characterized according to equations (13c) and (13d), which follow: σ 2 ⁡ ( q ) = 1 _ ⁢ ∑ m ⁢ ( q i - 〈 q 〉 ) 2 , ( 13 ⁢ c ) m i which may be rewritten as σ 2 ( q )≡ q 2 − q 2 .", "(13d) As previously noted, the set {q} is not a sampled data set, but defines the distribution.", "Furthermore, the standard deviation of a network variable is not an indication of the accuracy or error of the model, but rather it is a measure of the variation of the number of network elements or subsystems from locale to locale across the network.", "Note too that the value of the mean is independent of the variance.", "Thus, for example, the total cost for bandwidth management may be accurately predicted even while some nodes are smaller and cost less, and others are larger and cost more.", "[0065] The variance of the degrees of nodes is defined according to equation (13e), which follows: σ 2 (δ)≡ δ 2 − δ 2 , (13e) and so like δ i and δ , σ 2 (δ) is a function only of the network graph, G. Note, however, unlike δ there is no closed form expression for σ 2 (δ) as a function only of N and L. Rather the variance of the degrees of nodes implicitly depends upon the details of the network connectivity and must be computed from a representation of the graph, such as [g] or an equivalent link-list.", "If the network graph, or equivalently the link-list, is provided then functions of the degrees of nodes, such as the variance, may be computed exactly.", "[0067] As δ and L are directly proportional and the variance of δ is more closely related to [g], in some situations it may be useful to consider δz, 901 as the independent input variable and L as the dependent output variable.", "[0068] For the example network 200 of FIG. 2 having N=100 nodes and L=171 links, the mean degree of node is δ =3.4.", "The standard deviation of the nodal degree obtained from the network graph ( FIG. 2 ) is σ(δ)=1.1.", "By design, the mean degree of node and standard deviation of the nodal degree for the second example network having N=25 nodes and L=42 links are also δ =3.4 and σ(δ)=1.1.", "[heading-0069] Number of Hops [0070] The number of hops between a pair of nodes is defined as the minimum number of inter-nodal links traversed by a demand between the terminating node pair.", "Algorithms for determining the minimum number of hops h ij between node pairs (i,j) from the matrix representing the network graph [g] are well known, and so [h] and h may be readily computed given a demand model.", "The expectation value of the minimum number of hops is over the set of demands, (e.g., h d ), and may be characterized according to equation (14a), which follows: 〈 h 〉 = 1 D ⁢ ∑ i <", "j ⁢ D ⁢ h ij = 1 2 ⁢ D ⁢ ∑ i , j D ⁢ h ij .", "( 14 ⁢ a ) If the network graph and demands are provided, then (h) may be computed exactly.", "However, h may also be approximated for uniform, location-independent, or random demands with knowledge only of the number of nodes and number of links, as will be discussed in more detail below.", "[0072] The dependency of the average number of hops on the number of nodes N and number of links L may be formulated by considering the schematic of the network graph.", "If the outer boundary of the N nodes of a planar network arranged is visualized roughly as a square with {square root}N nodes on each of the two orthogonal sides, the characteristic distance between nodes measured in units of hops scales as {square root}N for uniform demand.", "In addition, the mean number of hops decreases as the number of links L increases for fixed N. An approximate analytic relationship describing the dependency of the mean number of hops on the number of nodes N and the mean degree of the nodes, δ , may be derived by considering a single node at the center of a regular network of constant degree, δ.", "In this case, the mean number of hops is approximately h ≅0.94{square root}(N−1)/ δ ′.", "This expression slightly under predicts the correct result in the special case where each node is connected directly to every other node via a dedicated physical link (i.e. δ=N−1 and h ≡1).", "Brute force evaluation of the mean number of hops for regular networks of constant degree for δ=3 and δ=4, except for the nodes at the perimeter, yields h ≅1.2{square root}N/<", "δ ′, which slightly over-predicts the means number of hops for the special case of δ=N−1 and h ≡1.", "[0073] In order to provide accurate compact analytic expressions for all variables for a wide range of networks, the inventor analyzed the average number of hops of several prototypical networks that were designed to be survivable under all possible single link failures.", "(Note, the failure of a single link implies the simultaneous failure of all demands appearing on the specified inter-nodal segment, which may be a very large number of demands.) This feature of network survivability translates into the requirement that the degrees of nodes for all nodes be greater than or equal to two (i.e., δ≧2).", "The exact results for the mean number of hops were fitted using the method of least squares deviation to determine the single coefficient of proportionality that best describes the data for all the networks considered.", "In total data for 14 mesh networks with numbers of nodes spanning the range 4≦N≦100 and average degree of node spanning the range 2.5≦(δ)≦5 were included.", "It was determined by the inventor that the expectation value of the number of hops for these networks with uniform demand may be expressed semi-empirically by the relation of equation (14b), which follows: h ≅1.12 {square root}{square root over (N/δ)} (14b) with a standard deviation of approximately 10 percent, and more accurately by the relation h ≅{square root}( N− 2){overscore (/( δ −1))}, (14c) with a standard deviation of approximately 2 percent.", "[0076] These approximate formulae may be applied to the case of uniform, location-independent, or random demand.", "For fixed network topology, it is expected for the average number of hops to decrease for distance dependent demand models that weigh shorter distance demands more heavily than longer distance demands.", "[0077] The estimate of the mean number of hops for the example network 200 of FIG. 2 having N=100 nodes and L=171 links determined using equation (14c) above is h ≅6.1, which may be compared to the actual mean of h =6.6.", "For the example network having N=25 nodes and L=42 links, the mean number of hops determined using equation (14c) is approximately h ≅3.0.", "[0078] The variance of the number of hops may be computed from [h] using equation (13);", "however, it is not necessary to compute σ 2 (h) explicitly for the analyses that follow.", "The range of hops extends from 1 to some maximum number H, which is often referred to as the diameter of the network.", "[heading-0079] Demands on Link [0080] It is evident that as a demand d ij is routed across the network between terminating nodes (i,j) that the demand occupies a unit of transmission capacity on each of the links connecting the nodes.", "The minimum number of links occupied by a demand is, of course, the minimum number of hops h ij from node i to node j. Consequently, the average number of demands carried on a link in the absence of extra capacity for restoration may be characterized according to equations (15a) and (15b), which follow: 〈 W 0 〉 = 1 L ⁢ ∑ i L ⁢ D i × 1 = 1 L ⁢ ∑ i , j D ⁢ 1 × h ij = 1 L ⁢ D D ⁢ ∑ i , j D ⁢ h ij = D ⁢ 〈 h 〉 D L , ( 15 ⁢ a ) which may be rewritten in the convenient form W 0 = d h / δ (15b) using equations (11b) and (13b).", "The expression of equation (15b) is exact and valid and independent of the demand model;", "however, the value of h is implicitly dependent upon the demand model, as discussed earlier.", "In the cases of uniform or random demand, if an approximation for h such as equations (14b) or (14c), is used to compute W 0 , then of course the result is also approximate, and the relative error of h determines the relative error of W 0 .", "[0083] For uniform demand, the value for d in equation (15b) may be substituted to obtain equation (15c), which follows: W 0 =( N− 1) h / δ .", "(15c) Using equation (15c), the mean number of channels carried on a link for the first example network 200 of FIG. 2 having N=100 nodes and L=171 links ( δ =3.4 and h ≅6.1) is estimated to be W 0 ≅178.", "Similarly, the mean number of channels on a link for the second example network having N=25 nodes and L=42 links ( δ =3.4 and h ≅3.0) is estimated to be W 0 =22.", "[0085] As suggested by equation (15b), variations in the number of channels carried on the individual links of the network may arise from differences in the number of demands terminating at the nodes connected to the links, the degrees of the nodes connected to the link, and also the routing constraints and algorithms.", "Here the case of uniform demand is considered, and the fluctuations that may arise when the demands are routed across the network under the constraint of minimum hop routing are first considered.", "In general, for any pair of nodes there will be one or more routes of minimum number of hops between the nodes.", "Consequently, the variation in the number of channels carried on a link will depend upon the selection criteria for choosing from among the set of minimum hop routes, which are referred to by the inventor as hop-degenerate routes.", "If it is assumed that the path is selected at random from the hop-degenerate routes, then the variance may be estimated using statistical methods.", "In particular, for the scenario just described, the distribution of the demands among the minimum hop routes is described by the binomial distribution.", "As such, an approximate expression for the variance of W o is derived by the inventor considering random routing over paths of equal numbers of hops.", "[0086] Referring back to equations (15a)-(15c) above, the mean value for the number of channels on a link for uniform two-way demand may be explicitly characterized according to equation (15d), which follows: 〈 W 0 〉 = 1 L ⁢ 1 2 ⁢ ∑ i N ⁢ ∑ j N - 1 ⁢ h ij = N ⁡ ( N - 1 ) ⁢ 〈 h 〉 / 2 ⁢ L .", "( 15 ⁢ d ) [0087] For a given node pair (i,j), all the paths of minimum hops h ij between them are considered, and l ij is used to denote the total number of distinct links among the set of hop-degenerate routes.", "These distinct links are labeled using the subscript k and p k is used to denote the probability that a link is selected.", "By construction, the set of probabilities {p k } satisfies equation (15e), which follows: h ij = ∑ k I ij ⁢ p k , ( 15 ⁢ e ) and consequently, p k ≅h ij /l ij .", "As an example, consider an illustrative case when there are three (r=3) link-disjoint routes of four (h=4) (minimum) hops between a pair of nodes.", "In this case l ij =r×h=3×4=12.", "As the paths are assumed to be disjoint, we may use equation (15e) to solve for p k with the result p k =h ij /l ij =h/(rh)=1/r=⅓ for each link.", "[0089] Substituting equation (15e) into equation (15d) results in equation (15f), which follows: 〈 W 0 〉 = 1 2 ⁢ L ⁢ ∑ i N ⁢ ∑ j N - 1 ⁢ ∑ k I ij ⁢ p k .", "( 15 ⁢ f ) Using the properties of the binomial distribution, the corresponding variance σ 2 (W o ) may be characterized according to equations (15g) and (15h), which follow: σ 2 ⁡ ( W 0 ) = 1 2 ⁢ L ⁢ ∑ i N ⁢ ∑ j N - 1 ⁢ ∑ k I ij ⁢ p k ⁡ ( 1 - p k ) , ( 15 ⁢ g ) using equations (15e) and (15f), equation (15g) may be rewritten as σ 2 ⁡ ( W 0 ) = 〈 W 0 〉 ⁡ [ 1 - 1 N ⁡ ( N - 1 ) ⁢ 〈 h 〉 ⁢ ∑ i N ⁢ ∑ j N - 1 ⁢ ∑ k I ij ⁢ p k 2 ] .", "( 15 ⁢ h ) [0092] To evaluate the sums we next group the sum over the N−1 nodes into sets of constant numbers of hops, h. Let there be N h nodes of h hops, and label each node by the index n. For each node the number of distinct links among the possible routes of h hops is denoted l n,h .", "If H is the largest value of the set of minimum number of hops, then equation (15h) may be rewritten according to equation (15i), which follows: σ 2 ⁡ ( W 0 ) = 〈 W 0 〉 ⁡ [ 1 - 1 〈 h 〉 ⁢ 1 N ⁢ ∑ i N ⁢ 1 N - 1 ⁢ ∑ h H ⁢ ∑ n N h ⁢ ∑ k I nh ⁢ p k 2 ] .", "( 15 ⁢ i ) The above expression is exact under the assumption of uniform demand and random routing.", "[0094] To carry this result further, an approximation for a planar network of average degree <δ>", "is derived.", "In this case the maximum number of hops H is characterized according to equation (15j), which follows: N− 1= δ [ H ( H+ 1)]/2, (15j) and the value of H is related to h by H≅{square root}2 h .", "[0096] When focusing on a single node within the network, the nodes that may be reached in h minimum hops are identified as approximately δ h in number.", "The options for routing from the node under consideration to each of the other nodes h minimum hops away are subsequently considered.", "There is at least one possible route and the number of hop-degenerate routes are denoted by the inventor as r. Next, the number of distinct links l n,h among these r hop-degenerate routes are identified and counted.", "For the planar network, the number of distinct links l n,h is less than h 2 ;", "the latter being the number in the situation when the hop-degenerate routes are link-disjoint paths.", "Consequently, the probability any one link is selected when choosing a path randomly from among the hop-degenerate routes of the network is greater than 1/h, which may be characterized according to (15k), which follows: p k ≧1 /h.", "(15k) This expression for the probability that a link is selected permits the formal bounding of the variance of the number of channels.", "Substituting equation (15k) into equation (15i), carrying out the sums and using equation (15j) yields equations (15l) and (15m), which follow: σ 2 ⁡ ( W 0 ) ≤ 〈 W 0 〉 ⁡ [ 1 - 1 / 〈 h 〉 ] ⁢ ⁢ and ( 15 ⁢ l ) σ ⁡ ( W o ) 〈 W 0 〉 ≤ 1 - 1 〈 h 〉 / 〈 W 0 〉 ≤ 1 √ 〈 W 0 〉 ( 15 ⁢ m ) [0098] The form of the variance in equation (15l) is that of a binomial distribution with probability 1/<h>.", "Thus, the actual distribution is approximated by the corresponding binomial distribution F(W=w), which is characterized according to equations (15n)-(15q), which follow: F ( W=w )=( w max |w ) p w (1 −p ) w max −w , w= 0, 1 , .", ", w max (15n) with p= 1/ h (15o) w max ≡ W 0 h (15p) and ( w max |w )= w max !", "/[w !", "( w max −w )!", "(15q) The binomial tail probability F(W≧w) may be determined using the incomplete beta function.", "[0101] Using Eq.", "15l, the standard deviation of the number of channels on a link for the example network 200 of FIG. 2 having N=100 nodes and L=171 links ( δ =3.4 and h =6.1) is estimated to be σ(W o )≦12.", "Recall the mean number of channels on a link was estimated to be (W o )≅178 for this network.", "Again using Eq.", "15l, the standard deviation of the number of channels on a link for the example network 200 of FIG. 2 having network of N=25 nodes and L=42 links ( δ =3.4 and h =3.0) is estimated to be σ W o ≅3.8.", "The mean number of channels on a link was estimated to be W o ≅22 in this case.", "[0102] In the above consideration of the variation of W o , the inventor recognizes that usually when traffic is routed and the network is optimized, paths are selected based on criteria such as the minimum number of hops, the shortest distance, or more generally the minimum cost.", "However, routing solutions that may be proven to be optimal are possible only for relatively small networks and, therefore, additional heuristic constraints are often imposed as strategies to ensure low cost.", "To minimize the cost of survivable networks, for example, algorithms to balance the traffic among the links are often introduced.", "By its definition, load-balancing deliberately seeks to dampen the variation of the number of channels carried on a link.", "Clearly if load-balancing is effective then the selection of paths from among the hop-degenerate routes is not random and σ(W o ) should be reduced relative to the value specified by equation (15l) above.", "As a corollary, the ratio of the achieved variance to the value obtained for random routing is a measure of the success of the load-balancing algorithm.", "[0103] The variance of the number of channels carried on a link derived above is a network global expectation based on routing decisions.", "A local view of the variations and the number of channels carried on a particular link (i,j) and their relationship to the terminating traffic and degrees of the local nodes may also be considered.", "A form for W ij based on equation (15b) and an heuristic argument based upon the routed traffic may be developed.", "Equation (15b) may be written to identify the local traffic terminating at the nodes connected to the link (both ends) and the through traffic that passes by both nodes according to equation (15r), which follows: W o =2 d / δ + d ( h −2)/ δ .", "(15r) The first term corresponds to the division of the terminating traffic among the various links connected to the terminating nodes.", "Assuming minimum hop routing, to a good approximation the terminating traffic is equally distributed among all the links connected to the node.", "This implies a direct correlation of the first term of equation (15r) to the local degrees of nodes connected to the link.", "The second term, however, corresponds to the many channels traversing the link that have destinations distributed across the entire network.", "For the moment it is considered that the traffic is routed to minimize the number of hops, but otherwise no preference among the individual links is imposed.", "Under these circumstances it is hypothesized that the second term has negligible correlation to the local degrees of nodes and is best described by a combination of the mean value and variations randomly distributed across the network.", "Therefore, the number of channels on a link may be characterized according to equations (15s) and (15t), which follow: W ij =W B/E +W B/T (15s) with W B/E ≡d i (1/δ i +1/δ j )−1.", "(15t) (The right most “−1”", "in equation (15t) ensures the proper accounting of the demand between node i and node j.) The variable W B/T includes random variations in the number of through channels and satisfies equation (15u), which follows: W B/T ≡ d ( h −2)/ δ +1.", "(15u) The variance of W B/T may be estimated using the statistical formalism described above with respect to equation (15l) with W B/T replacing W o and W B/T replacing W o .", "[0108] It can be verified by direct computation that the expectation value of W i,j (equations 15s-15u) yields W o (equation 15r) in the case of location-independent demand, as required.", "As the second term of equation 15r is locally uncorrelated with the first term, the variance of W o may therefore be expressed according to equation (15v), which follows: σ 2 ( W o )≅(2/ δ ) 2 σ 2 ( d )+ d 2 σ 2 (1/δ)+σ 2 ( W W/T ) (15v) The variance associated with routing decisions implicitly assuming no variation in δ has already been estimated using equation (15l).", "Now, the relative size of the variance in W o attributable to variations in the degrees of the nodes may also be estimated.", "The variations correlated to the local degrees of nodes (i.e., the second term of equation (15v)), may be computed directly from the network graph.", "For the present it should be noted that for uniform demand σ 2 (d)≡0, and σ( W B/E )/ W B/E ≅{square root}{square root over ([ δ n 1/δ n −1]/2)}.", "(15w) Using equations (15t) and (15w), the mean and standard deviation of the number of A/D channels terminating at the two ends of a link are estimated to be W B/E ≅58 and σ(W B/E )≦13, respectively, for the example network 200 of FIG. 2 having N=100 nodes and L=171 links ( δ =3.4, h ≅6.1, 1/δ =0.32).", "The mean number of channels not terminating at either end of a link is approximately W B/T ≅120 for this network.", "For the smaller example network having N=25 nodes and L=42 links ( δ =3.4, h ≅3.0, 1/δ =0.32) the mean and standard deviation of the number of A/D channels terminating at the two ends of a link are estimated to be W B/E ≅14 and σ(W B/E )≦2.8.", "The mean number of channels not terminating at either end of a link is approximately W B/T ≅7.5 for this example.", "[0111] If the terminating demands are not uniformly distributed, but instead randomly distributed, then the first term in equation (15v) proportional to σ 2 (d) (i.e., σ d 2 (W o )) also contributes to the variance of W o according to equation (15x), which follows: σ d ( W o )/ W o =[2/ h ][(σ( d )/ d ].", "(15x) As previously stated, the expressions for W o (equations (15b) and (15c)) are exact and independent of the estimations of σ(W o ).", "Restoration Capacity [0114] The additional capacity added to links to ensure network survivability depends upon the types of failures considered, the restoration strategy strategy, and the blocking characteristics of the cross-connects used to redirect the affected traffic over alternate routes.", "For the purpose of architectural comparisons, network survivability is very often defined in relation to single link failures (i.e., the network is designed and minimally sufficient capacity is deployed to ensure the network can support the traffic and is survivable against all single link failures).", "As explained earlier, this implies the network has sufficient extra capacity to restore all of the simultaneously failed demands sharing the common failed link.", "Extra capacity is counted in units of additional channel-links and is most often reported as a fractional increase above the total number of channel-links for minimum hop routing.", "Using that convention, the average number of channels on a link including extra capacity for restoration may be characterized according to equation (16a), which follows: W κ ≡ W o (1+ κ ).", "(16a) The superscript designation κ is introduced to W to indicate that the expression accounts for extra capacity for restoration.", "This expression is independent of the demand model.", "In considering the individual failure of all the δi+δj−1 links that are connected to the two nodes at the ends of link (i,j), the number of channels on an individual link (i,j) including the extra capacity for restoration is characterized according to equation (16b), which follows: W κ ij =W ij + W o κ ij , (16b) where W ij and W o are given by equations (15t)-(15v) and equation (15s), respectively.", "The mean value of this model for W κ ij yields equation (16a), as required.", "Below formulae are developed for κ and κ ij as functions of the input network variables.", "[0117] Precisely determining the amount of additional capacity requires a detailed network analysis and a non-trivial exercise for large mesh networks.", "Obtaining exact results for general mesh networks when the number of nodes is more than about 20 is presently not practical because of the magnitude and duration of the numerical computations.", "Thus, some form of heuristic algorithm for routing traffic and assigning restoration capacity is usually employed for large networks.", "[0118] In considering the extra capacity that must be deployed to ensure survivability against single link failures, a general inverse dependency upon the degree of the nodes is readily recognized and explained qualitatively.", "For example, a ring network (which by definition has an average degree of node equal to 2) with dedicated protection requires 100% extra capacity relative to the minimum capacity necessary to carry the traffic demand.", "As such, a qualitative relationship between the fractional increase in capacity on a link and the degree of the node to which the link is connected may be characterized according to equation (17a), which follows: κ˜1/(δ−1).", "(17a) However, a strict interpretation of equation (17a) as an equality can under-predict by one-third or more the necessary extra capacity for planar mesh networks when δ is greater than 2.", "To assess the feasibility of using an analytic equation to model the extra capacity, we have fitted the extra capacity determined by detailed calculation and simulation of mesh networks with uniform demands for the case of strictly non-blocking cross-connects using the expression κ =( a−b )/( δ − b ), (17b) where a and b are parameters to be determined semi-empirically.", "[0121] The results for the extra capacity for 8 mesh networks are considered and the condition is also imposed that κ =1 for δ =2.", "The mesh networks had numbers of nodes N in the range of 4≦N≦100, average degree of node in the range of 2.5≦ δ ≦4.5, and required an average extra capacity in the range of 0.4≦ κ ≦0.9.", "The constraint to describe the ring network exactly using equation (17b) requires a =2.", "The best value of b was then determined to be b=−0.4.", "Within the accuracy (σ≅±17%) of the fitted results, the functional form for the extra capacity may be characterized according to equation (17c), which follows: κ ≅2/ δ .", "(17c) The form of equation (17c) for the required extra capacity in the case of single link failures suggests that only one-half of the links connected to a node in common with the failed link participate in carrying the rerouted traffic.", "This is understood qualitatively when it is considered that using the other one-half of the links would result in diverting the rerouted traffic further away from its intended destination and consequently over even longer paths, which may introduce increased signal impairments, such as longer latency and higher bit-error-rate, as well as the complexity of involving larger numbers of nodes.", "For completeness an expression is noted for the extra capacity on the individual links that results in the expectation value of the extra capacity given by equation (17c), which is characterized according to equations (17d) and (17e), which follow: κ ij = 1 2 ⁡ [ 2 / δ j + 2 / δ j ] ⁢ ⁢ and ( 17 ⁢ d ) 〈 κ 〉 ≡ 1 L ⁢ ∑ i , j L ⁢ κ i , j ≅ 1 L ⁢ ∑ i , j L ⁢ ( 1 δ i + 1 δ j ) = 1 L ⁢ ∑ n M ⁢ ∑ κ δ n ⁢ 1 δ n = N L = 2 〈 δ 〉 ( 17 ⁢ e ) or more explicitly κ l =2/ δ n .", "It should be noted however, that based on equation (17e), the property that 1/δ l =1/ δ n .", "However, in general, 1/δ n ≠1/ δ n except for in regular networks of constant degree, δ, or as an approximation.", "[0124] A slightly more accurate semi-empirical representation (σ≅±12%) of the values of the extra capacities of the networks considered is characterized according to equations (17f) and (17g), which follow: κ l = 2/δ n , (17f) for which the corresponding local extra capacity is κ ij =½[(2/δ i ) 2 +(2/δ j ) 2 ]/[2/ δ ].", "(17g) In both cases it is clear there is a strong correlation between the efficient use of spare capacity for survivability and the degrees of the nodes.", "Note too that the success of equations (17c)-(17g) in representing the required extra capacity also reinforces the postulation that the traffic load is relatively balanced on the individual links (i.e., equation (15b).", "It is also expected that the approximate analytic expressions for κ (e.g., equations (17)) hold independent of the demand model, as they were hypothesized based on the mesh topology of the network, and not explicitly upon the demand model.", "Finally, it is pointed out that the additional capacity required for dynamic networks, such as for survivable networks, will be larger if the cross-connects are not strictly non-blocking.", "For example, in the case of wavelength-division-multiplexed line systems and cross-connects without wavelength interchange except at the terminations, the increase of the extra capacity for restoration above the minimum value for strictly non-blocking cross-connects is typically in the range of only 5-20%, although the management complexity is greatly increased.", "[0127] For the example network 200 of FIG. 2 having N=100 nodes and L=171 links ( δ =3.4), the mean value of the extra capacity to ensure survivability under single link failures is estimated to be κ ≅0.58.", "As the mean degree of node for the second example network having N=25 nodes and L=42 links is nearly identical to that of the larger network by design, δ ≅3.4, the estimate for the mean value of the extra capacity to ensure survivability under single link failures is also nearly the same at κ ≅0.60.", "[0128] As described above, the extra capacity on individual links has been modeled in a manner that is both intuitive and consistent with empirical observations of the total extra capacity.", "The model for {κ} depends only upon the degrees of the nodes, {δ}, and consequently it is a function of the input network graph G, as stated explicitly in equation (13a).", "[heading-0129] Traffic on Link [0130] The average traffic carried on a link β is the product of the average number of demands on a link W and the termination-to-termination traffic per demand τ, and is characterized according to equation (18a), which follows: β ≡ W τ=τ h D/L = h T/L.", "(18a) This direct proportionality is independent of the demand model.", "[0132] FIG. 5 graphically depicts a plot of the mean traffic on a link including idle restoration channels for uniform demand as a function of the number of nodes N and total network traffic T. In FIG. 5 , the mean traffic on a link β κ (N, T) for uniform demand with restoration is graphed as a function of the number of nodes N and total two-way traffic under the constraint δ =3.5 using a contour plot.", "[0133] For the example network 200 of FIG. 2 having N=100 nodes, L=171 links, and T=5 Tb/s, the mean value of the traffic carried on a link including extra capacity for restoration is β κ ≅284 Gb/s.", "In comparison, the mean value of the traffic carried on a link including extra capacity for restoration for the smaller example network having N=25 nodes, L=42 links, and T=1 Tb/s, is β κ ≅16 Gb/s.", "[0134] Based on the preceding discussions, the inventor determined that the variance of β is determined by the variance of W and that the variances are related according to equation (18b), which follows: σ(β)/ β =σ( W )/ W .", "(18b) Number of Ports and Capacity of a Cross-Connect [0136] Among the key attributes of cross-connects are the port count, P, and total capacity, χ.", "The average number of ports on a cross-connect in a mesh network can be determined by counting the number of ports that each demand occupies as it traverses the network, tallying the number of ports for all demands, and then dividing by the number of cross-connects.", "By design a cross-connect—of which an add-drop multiplexer is considered a special case—is placed at each node of the backbone network to manage transport bandwidth, and so the number of cross-connects is given by the number of nodes, N. [0137] As illustrated in FIG. 3 , the number of output ports is usually equal to the number of inputs.", "Also, a P×P cross-connect, which has P inputs and P outputs (or P I/O ports), supports connections among P two-way channels.", "[0138] The average number of one-way input ports, P 1 is first calculated.", "FIG. 6 depicts a high level block diagram of two cross-connect ports 610 , 620 and the relationship among the local ADD, DROP and THRU channels.", "FIG. 6 illustratively serves as a guide to counting the number of cross-connect ports occupied by a demand as it traverses a network.", "In FIG. 6 , the numbers of add and drop demands, depicted as N−1, specifically correspond to the uniform demand model.", "Referring to FIG. 6 , consider a directed demand that enters, or is added to, the network via the cross-connect of the node on the left.", "Adding the demand requires one input port.", "Eventually, this demand exits the network.", "Dropping from the network is accomplished by entering and exiting the cross-connect at the destination node, which may be considered the node on the right of FIG. 6 .", "Thus, dropping the demand also requires one input port.", "Additionally, in traversing the network the demand under consideration occupies input ports at the cross-connects of the intervening nodes.", "Having defined “h”", "as the number of inter-terminal hops, the number of intervening cross-connects that the demand enters is h−1.", "Consequently, the number of input ports that a one-way demand occupies may be characterized according to equation (19a), which follows: p ij =1+1+( h ij −1)= 1+h ij .", "(19a) The total number of input ports occupied by all demands is therefore characterized according to equation (19b), which follows: P t = ∑ i , j D 1 ⁢ [ 1 + h i , j ] = D 1 D 1 ⁢ ∑ i , j D 1 ⁢ [ 1 + h i , j ] = D 1 ⁢ 〈 1 + h i , j 〉 = N ⁢ 〈 d 〉 ⁡ [ 1 + ⁣ 〈 h 〉 ] , ( 19 ⁢ b ) and the average number of input ports P 1 occupied on a cross-connect at a node is characterized according to equation (19c), which follows: P 1 =( D 1 /N )[1+ h ]= d [1+ h ].", "(19c) Equations (19a)-(19c) are valid independent of the demand model;", "while as before the value of h is implicitly dependent upon the demand model.", "For the case of a mesh network with uniform demands, d in equation (19c) is substituted using equation (11c) to obtain equation (19d), which follows: P 1 =( N− 1)[1+ h ], (19d) where h may be approximated using equation (14b) or equation (14c).", "[0143] For completeness, the average number of two-way ports for a cross-connect of the same network is computed.", "The number of two-way terminations for a two-way demand is 2, one at each terminus.", "The average number of two-way thru ports occupied is 2[1+ h ] and the total number of two-way ports occupied is characterized according to equation (19e), which follows: P t = ∑ i <", "j D 2 ⁢ [ 1 + h i , j ] = D 2 D 2 ⁢ ∑ 2 i <", "j D 2 ⁡ [ 1 + h i , j ] = 2 ⁢ D 2 ⁢ 〈 1 + h i , j 〉 = 2 ⁢ ⁢ D 2 ⁡ [ 1 + ⁣ 〈 h 〉 ] .", "( 19 ⁢ e ) Thus, the average number of two-way ports is characterized according to equation (19f), which follows: P 2 =2( D 2 /N )[1+ h ].", "(19f) By substituting for D 2 using equation (10c), the inventor has determined equation (20a), which follows: P ≡ P 2 = P 1 , (20a) which may be appreciated by again considering FIG. 3 .", "This result is independent of the demand model and may also be structured to explicitly indicate the add, drop and through ports.", "Considering FIG. 6 and equation (20a) above, the inventor proposes equation (20b), which follows: P ≡ P ADD + P DROP + P THRU (20b) where P ADD = P DROP = d (20c) and P THRU = d ( h− 1) (20d) and as such, P ADD + P DROP =2 d .", "(20e) As previously stated, every demand occupies both a termination-side port and line-side port on each of the two cross-connects at the opposite ends of the demand.", "Another common partitioning of ports is between termination-side ports and line-side ports.", "In this case equation (20b) is rewritten according to equation (20f), which follows: P ≡ P TERM + P LINE (20f) where P TERM = P ADD = d (20g) and P LINE = P DROP + P THRU = d h .", "(20h) [0153] In the above analysis for the average number of ports, the extra transmission capacity and extra cross-connect ports that are required for network survivability were introduced.", "As discussed earlier, for single-link failure scenarios, the link or line-side capacity is increased by the fraction <κ>.", "Thus, the total number of cross-connect ports for shared line-side restoration of mesh networks is obtained by introducing the extra capacity factor into equations (20h) and ( 19 c ), which results in equation (21 a), which follows: P κ = d [1+(1+ κ ) h ].", "(21 a) The same result is also obtained considering that the total number of ports is the sum of the number of channels carried on each of the links connected to the node and the number of channels terminating at the node.", "The former is given by the product of W o and δ, and therefore yields equation (21b), which follows: P κ = d + W o (1+ κ ) δ .", "(21b) Using equations (13b) and (15b) and the definition of κ it can be determined and illustrated that equation (21b) equates to equation (21a).", "[0156] To appreciate how P scales with the number of nodes, equations (21) may be considered for uniform traffic in the limit when N is large compared to 1.", "In that limit and using equations (11c), (14c) and (17c) for d , h and κ , respectively, equation (21b) may be rewritten according to equation (22a), which follows: P κ ≈[(1+2/ δ )/{square root} δ ] N 3/2 .", "(22a) For networks with δ in the range of 3≦ δ ≦4, the term in equation (21b) dependent upon δ is within 14% of unity and for δ =3.5, the coefficient differs from 1 by less than 5%.", "Consequently, equation (22a) may be rewritten according to equation (22b), which follows: P κ N 3/2 .", "(22b) Thus, if the number of nodes in the network is approximately 24, then the average number of ports required is about 125.", "When N is about 100, then P κ ˜3000.", "Similarly, the average traffic cross-section carried on the route between adjacent nodes is characterized according to equation (23), which follows: W κ ≈ N 3/2 / δ (23) when N is large compared to unity.", "[0160] The average traffic handled by a cross-connect χ , measured in bits/second for example, is now computed straightforwardly from the average number of ports P and the communication bandwidth, either τ or B, associated with the basic unit of demand.", "Of course the former corresponds to the case when the channel utilization is 100% and the latter may correspond to a particular system increment or industry standard.", "Thus the average traffic handled by a cross-connect χ may be characterized according to equation (24a), which follows: χ(τ) ≡ P τ (24a) or χ( B ) >≡ P B. (24b) These direct proportionalities are independent of the demand model.", "[0163] For the example network 200 of FIG. 2 having N=100 nodes and L= 171 links, the mean number of ports on a cross-connect including ports for restoration is estimated to be P κ ≅1061.", "The corresponding mean cross-connect traffic is 1072 Gb/s.", "For the smaller example network having N=25 nodes and L=42 links, the mean number of ports on a cross-connect including ports for restoration is estimated to be P κ ≅141.", "The corresponding mean cross-connect traffic is 469 Gb/s.", "[0164] To compute the variance of the number of ports, P, the number of ports required for the individual nodes must be determined.", "In the preceding sections, expressions for the number of channels on the individual links have been formulated;", "namely equations (15d-15g), equation (16b), and equation (17d).", "Consequently, it is necessary only to add the termination side channels to the sum of the channels on the δ i links connected to an individual node i to obtain the sum of the ports, P κ i .", "Such an expression may be characterized according to equation (25a), which follows: P i κ = d i + ∑ j δ i ⁢ W ij κ .", "( 25 ⁢ a ) Hence, the variance of P κ may be computed using this expression and the definition of the variance, equation (13d).", "In the spirit of clarifying the dependencies of the variance of P κ , the following illustrates an example where the local extra capacity for restoration is specified by equation (17d).", "In this scenario the number of ports on a local cross-connect is characterized according to equation (26a), which follows: P κ i ≅2 d i +[d i / δ + W B/T + W o / δ ]δ i + W o , (26a) where for the total extra capacity associated with ports at node i, the approximation in equation (26b), which follows, was used: κ i = ∑ j δ i ⁢ κ ij ≅ 1 + δ i 〈 δ 〉 .", "( 26 ⁢ b ) [0167] Considering equation (26a), it is observed that there is a correlation between P κ i and δ i that is moderated by the variations in W T .", "The variance of P κ for uniform demand is characterized according to equation (27a), which follows: σ 2 ( P κ )≅[ d / δ + W B/T + W o / δ ] 2 σ 2 (δ)+ δ 2 σ 2 ( W T ) (27a) and the total number of ports, P κ is characterized according to equation (27b), which follows: P κ i ≅2 d i +[d i / δ + W B/T ]δ i + W o δ /δ i + W o δ 1/δ .", "(27b) In this case there is a contribution to the number of ports from the extra capacity (1/δ i ) that is anti-correlated with the main term that is proportional to δ i .", "Thus, it is expected that the variance of P κ in this scenario for the extra capacity, equation (17g), to be somewhat less than the variance obtained using the first form, equation (17d).", "To illustrate this behavior it was assumed that the variance of W T is small and may be neglected.", "In this situation the standard deviation for the number ports for both scenarios (equations (17d) and (17g)) for the extra restoration capacity on a link for uniform demand may be characterized according to equations (28a) and (28b), respectively, which follow: σ( P κ )= W o (1+2/ δ )σ(δ) (28a) and σ( P κ )= W o σ(δ) (28b) It is evident from the equations above that the standard deviation corresponding to the second form of the local extra capacity, which more strongly varies with the local degree of the node, is smaller by a factor of 1/(1+2/ δ ).", "This is understood considering that nodes with smaller degree require larger extra capacity on connecting links and nodes with larger degree require less extra capacity on connecting links.", "As a result of this anti-correlation the distribution of the required ports is narrowed.", "[0172] For the example network 200 of FIG. 2 having N=100 nodes and L=171 links the mean and standard deviation of the degree of nodes is δ =3.4 and σ(δ)=1.1.", "Consequently, the standard deviation of the number of ports on a cross-connect based on the variance of the degrees of nodes is estimated to be σ(P κ )≅307 and σ(P κ )≅194 using equation (28a) and equation (28b), respectively.", "Recall the mean number of ports including restoration capacity was estimated to be P κ ≅1061.", "It is expected that the fractional deviations for the smaller example network having N=25 Nodes and L=42 links will be similar, as the statistics of the degrees of nodes are nearly the same by design.", "Again using equation (28a) and equation (28b), the standard deviation of the number of ports on a cross-connect for this smaller network is estimated to be σ(P κ )≅38 and σ(P κ )≅24, respectively.", "Recall that the mean number of ports including restoration capacity was estimated to be (P κ )≅141.", "[0173] In summary, in this and the preceding section it has been shown that the network global expectation model may be used to understand and predict the mean and variability of the number channels carried on links and present at the nodes, including the effects resulting from network survivability.", "It will be appreciate by one skilled in the relevant art informed by the teachings of the presenting invention that although the model has been illustratively applied to the case of uniform, location-independent, or random demand in this section on the variance of the number of ports, the methodology is directly applicable to other demand profiles.", "[heading-0174] Percentage Add/Drop [0175] Another important characteristic of the network is the percentage of add and drop traffic at a node.", "Referring to FIG. 6 and the one-way input ports on the cross-connect, it is observed that the average number of input ports occupied by traffic being either added or dropped at the node may be characterized according to equation (29a), which follows: P ADD + P DROP = D 1 /N+D 1 /N= 2 D 1 /N (29a) The average number input ports occupied by traffic passing through the node may be characterized according to equation (29b), which follows: P THRU = D 1 ( h −1)/ N. (29b) By definition the average ratio of the number of local add/drop ports to local total ports may be characterized according to equation (30a), which follows: 〈 ρ 〉 ≡ 1 N ⁢ ∑ n N ⁢ ( P ADD + P DROP ) n / P n , ( 30 ⁢ a ) which may be computed by substituting expressions for both the numerator and the denominator.", "However, another practical and useful definition of the add/drop ratio average is the ratio of the network total number of add/drop ports to network total ports.", "In this second case the ratio may be characterized according to equation (30b), which follows: ρ′ = N ( P ADD + P DROP )/ N ( P ADD + P DROP + P THRU )=( P ADD + P DROP )/ P (30b) and therefore ρ′ =2/[1+ h ].", "(30c) It should be noted that this relationship between ρ′ and h has been derived without reference to a model for the demands D 1 .", "Consequently, it is a general result and not restricted to the case of uniform demands.", "[0181] If the extra capacity for line-side restoration is accounted for, then the ratio average, ρ′ κ , of the number of add/drop ports to total ports (equations 21) may be characterized according to equation (30d), which follows: ρ′ κ =2/[1+(1+ κ ) h ].", "(30d) The estimated add/drop ratios for the example network 200 of FIG. 2 having N=100 nodes and L=171 links without and with extra capacity for restoration are ρ ≅0.28 and ρ′ κ =0.19 using equation (30c) and equation (30d), respectively.", "In comparison, the estimated add/drop ratios for the example network having N=25 nodes and L=42 links without and with extra capacity for restoration are ρ′ ≅0.49 through ρ′ κ ≅0.34 using equation (30c) and equation (30d), respectively.", "This trend of increasing the fraction of through traffic as the number of nodes is increased is a general characteristic of a single-tier network with uniform demand.", "In the limit when N is large compared to 1 and the average degree of node is in the range 3≦ δ ≦4 the total number of ports is given by equation (22b) and the add/drop ratio average may be characterized according to equation (30e), which follows: ρ′ κ ≈2 /{square root}N.", "(30e) Thus, for a mesh network of 25 nodes with shared line-side protection the ratio of add/drop to through channels is approximately 40% on average, and the percentage decreases as the number of nodes increases.", "Of course, this estimate is for the average node, and the percentage for a particular node can be larger or smaller depending upon the details of the network demand and topology.", "The use of shared termination-side protection will tend to increase the add/drop ratio.", "[0184] On a separate note related to the add/drop ratio, it is also worth pointing out that equation (30c) may be inverted to express h as a function of ρ′ , according to equation (31), which follows: h =[2/ ρ′ −1].", "(31) Like equation (30c), equation (31) is a general result and not a function of the demand model.", "[0186] The ratio of the add/drop traffic to total traffic for an individual note may be formulated using equations (25) and (29a).", "For example, considering the case when σ(W T ) is negligible, the result using equation (17d) for the extra capacity may be characterized according to equation (32a), which follows: ρ i κ = 2 ⁢ 〈 d 〉 P i κ = 2 1 + ( 1 + 2 〈 δ 〉 ) ⁢ 〈 d 〉 δ ⁢ δ i 〈 d 〉 .", "( 32 ⁢ a ) When N is large compared to 1 and δ is in the range of 3≦ δ ≦4, equation (32a) may be approximated according to equation (32b), which follows: ρ κ l ≈(2 /{square root}N )[ δ 3/2 /(1+2/ δ )](1/δ i ) (32b) and so in this case σ(ρ κ )/ ρ κ ≈σ(1/δ)/ 1/δ .", "(32c) Also, ρ κ min/max / ρ κ ≈ δ /δ max/min (32d) Thus, given that δ i may range from 2 to 8, it may be concluded that the add/drop ratio can conceivably range from ½ to 2 times the mean value.", "Network Cost [0192] In the previous section expectation values have been derived for the quantities of key network elements and network element subsystems required to carry out a basic cost analysis for a transport network.", "In this section the concept of the cost structure of network elements in relation to both the network elements and network element subsystems will be introduced.", "With an assumed cost structure, the total cost of the network as well as categories of costs may be computed, such as for transmission and bandwidth management.", "It is also illustrated by example how the network costs are compared using different combinations of technology, such as electronic and optical bandwidth management, using the network global expectation model.", "[0193] For the purpose of outlining the general principles of computing network costs using the network global expectation model, rudimentary cost structures are considered for the optical line system (OLS), electronic and cross-connect (EXC), and optical cross-connect (OXC).", "FIG. 7 depicts a high level block diagram of an exemplary architecture of OLS 710 , EXC 720 , and OXC 730 systems from a perspective near a node.", "In FIG. 7 , termination-side traffic enters the network at a node Via the EXC 720 where it is groomed (i.e., switched and multiplexed, into the fundamental units of inter-terminal bandwidth destined for specific nodes of the network).", "The groomed output channels from the EXC 720 then enter the OXC 730 , where they are directed to line systems placed along the inter-terminal links of the network according to the traffic routing scheme determined by either a centralized or distributed management system.", "In the architecture considered in FIG. 7 , the interfaces between network elements are illustratively optical translators (OTs), which ensure that the cost comparisons are under conditions of fixed network capability (features) and network performance.", "[heading-0194] Transmission Cost Structure [0195] A cost structure often used for optical fiber transmission is the average cost of transporting bandwidth (B) over distance (s).", "Herein this cost structure is represented as a cost coefficient, which is denoted as γ B-s .", "The units of γ B-s are dollars per gigabit per second per kilometer ($/Gbps/km).", "According to Gawrys, an approximate value for network transmission cost of a two-way channel may be characterized according to equation (33), which follows: γ B-s ≈$30 /Gbps/km (33) based on historical data and projections.", "[0197] Considering this cost structure, the individual and mean cost of a transmission link of a survivable mesh network may be characterized according to equations (34a) and (34b), respectively, which follow: C i =γ B-s βs i , (34a) and c 1 =γ B-s β s ≅γ B-s β s , (34b) where for the model of uniform demand under present consideration β is given by equation (16) with κ given by equation (17c) and s is the expectation value of the link length.", "The expectation value of the link length, s , may be characterized according to equation (35a), which follows: 〈 s 〉 = 1 L ⁢ ∑ l L ⁢ s l , ( 35 ⁢ a ) where the set {s} are the physical lengths of the individual links.", "If the link lengths are known, then the expectation value s is quickly computed.", "Here, for the purposes of illustration, without introducing a specific set of link lengths, it is noted that for two-dimensional mesh networks the average link length scales inversely with the square-root of the number of nodes and is proportional to the square-root of the geographic area covered by the network.", "Thus, the expectation value of the link length, s , may be characterized according to equation (35b), which follows: s ≅{square root} A /({square root} N− 1).", "(35b) The total cost of transmission is characterized according to equation (36a), which follows: C TRANS =L c 1 .", "(36a) wherein it should be clear that C TRANS is an analytic function of only the independent input network variables (N, the number of nodes;", "L, the number of links;", "T, the total ingress/egress traffic;", "and A, the geographic area covered by the network), and so is easily computed.", "Consequently, when N is large compared to 1 and δ is in the range of 3≦ δ 4, C TRANS may be approximated according to equation (36b), which follows: C TRANS ≈γ B-s T{square root}A.", "(36b) [0203] Currently, the yearly time averaged traffic carried by a combined voice and data backbone network in the continental United States is approximately 1 Tb/s.", "the daily and annual peak traffic load that the network must support is estimated to be ˜5× the average traffic.", "Thus, as an example we consider T=5 Tb/s.", "The geographic area of the continental U.S. is approximately A=8×10 6 km 2 .", "Thus, the approximate cost of transmission system equipment C TRANS to support the present traffic is approximately $400M.", "[0204] The approximate cost of transmission represented by equation (36b) is obviously an over simplification as it contains no dependency on the number of links.", "That behavior is not because of a shortcoming of the global network expectation model, but rather is attributed to our assumption of the cost structure, equations (33) and (34).", "Clearly a more realistic model of the cost structure for the link should include an explicit dependency upon the cost of optical fiber cable, the cost of end terminals, the cost of OTs, the cost of amplifiers, and the cost of amplifier pumps, for example.", "Realizing this, a refined cost structure for a link is characterized according to equation (37a), which follows: c i =γ t0 +γ t1 τW i +γ t2 s i +γ t3 τW i s i .", "(37a) The expectation value for the cost of a link may then be characterized according to equation (37b), which follows: 〈 c 1 〉 = 1 L ⁢ ∑ i L ⁢ c i = 1 L ⁢ ∑ i L ⁢ { γ t0 + γ t1 ⁢ τ ⁢ ⁢ W i + γ t2 ⁢ s i + γ t3 ⁢ τ ⁢ ⁢ W i ⁢ s i } , ( 37 ⁢ b ) where the first term containing γ t0 reflects fixed costs for a link, such as the cost of the terminal equipment bays;", "the second term containing γ t1 includes costs that depend directly upon the number of channels carried, such as the number of OTs, the third term containing γ t2 includes costs that depend upon the distance traversed, such as the cost of trenching, cost of fiber, and the cost of amplifiers;", "and the fourth term containing γ t3 includes contributions that grow as the product of distance and wavelength, such as the cost of growth pumps and premium for specialized high capacity, long-distance fiber (e.g., dispersion-managed cable).", "[0207] The total cost of transmission may then be characterized according to equation (37c), which follows: C TRANS =L c 1 = L{γ t0 +γ t1 τ W +γ t2 s +γ t3 τ W s }.", "(37c) Of the expectation values contained in equations (37), all have been previously computed except for W s .", "As previously described, the number of channels on a link for the case of uniform demands is nearly independent of the particular link.", "Thus, W s = W s and the total cost of transmission may be characterized according to equation (37d), which follows: C TRANS ≅L {γ t0 +γ t1 τ W +γ t2 s +γ t3 τ W s }.", "(37d) The above approximation is further validated when it is considered that under real world circumstances the coefficient γ t3 is small compared to the other coefficients and rarely are the optical line systems loaded to their maximum channel carrying capacity.", "In this case, to gain a better appreciation for how the total transmission cost depends upon the basic network variables, the last term is dropped.", "Upon substituting for the remaining expectation values in equation (37d), the cost of transmission may then be characterized according to equation (37e), which follows: C TRANS ( N, T )≅½[γ t0 +γ t2 δ N{square root}A /({square root} N− 1)+γ t1 [{square root}A (1+2)/ δ )/{square root}{square root over ( δ −1])} T. (37e) Here, the fixed startup costs (i.e., those independent of the traffic carried T) are evident in the first term, which is proportional to N or L (L=N<δ>/2,equation (13b)).", "Bandwidth Management Architectures and Cost Structure Electronic Bandwidth Management Only [0213] The network global expectation model provides the flexibility and ease of implementation to compute the network element variables and total network costs for a wide range of network sizes, total traffic, and a variety of architectural options.", "Herein it is illustrated how the costs for two different models of bandwidth management at the network nodes may be constructed.", "First considered is the case when an electronic cross-connect is used for both sub-rate grooming and cross-connect functions.", "In this case the total cost of bandwidth management is the cost of the electronic cross-connect, as is characterized in equation (38), which follows: C BWM =C EXC .", "(38) The total cost of the electronic cross-connects may be written in terms of the expectation value of the cost of the nodes according to equation (39a), which follows: C EXC = C EXC N, (39a) which follows directly from equation (8).", "An estimate of the current cost of high-speed electronic switching engines may be characterized according to equation (39b), which follows: γ ep ≈$1 K/Gbps, (39b) which corresponds to a cost structure of the local EXC characterized according to equation (39c), which follows: C EXC =γ ep χ(τ).", "(39c) Making use of equation (24a), the corresponding expectation value may be characterized according to equation (39d), which follows: c EXC =γ ep χ(τ) =γ ep τ P .", "(39d) Substituting for c EXC in equation (39a) and using equations (12a) and (21a), the value of C EXC may be characterized according to equation (39e), which follows: C EXC = c EXC N= 2γ ep T [(2+ κ ) h ].", "(39e) A more refined form for the cost structure of the electronic cross-connect, or IP router, that includes a startup term and a growth term may also be constructed according to equation (39f), which follows: c EXC =γ e0 +γ e1 χ τ .", "(39f) In this case C EXC ( N,T )= c EXC N=γ e0 N+ 2[(2+ κ ) h ]γ e1 T. (39g) These expressions for costs are valid independent of the demand model.", "Electronic and Optical Bandwidth Management [0223] Here a single-tier model using both optical and electronic bandwidth management is considered.", "More specifically, all traffic passes through the optical layer cross-connect and additionally all terminating traffic also passes through an electronic fabric for the purpose of channel grooming.", "Such an architecture is attractive when the cost of an optical port is significantly less than the cost of an electronic port for a given data rate.", "The total cost for BWM is thus characterized according to equation (40), which follows: C BWM =C EXC +C OXC (40) Cost of Electronic Ports for Termination-Side Traffic [0225] As before, it is assumed that the cost of the electronic switch consists of a startup term and a term proportional to the traffic handled.", "However, herein only the terminating traffic traverses the EXC.", "Thus the mean cost of an EXC is characterized according to equations (41a)-(41c), which follow: c EXC =γ e0 +γ e1 τ P ADD +P DROP =γ e0 +γ e1 2τ P ADD , (41a) which, using equation (12) for τ, may be rewritten as c EXC =γ e0 +4γ e1 T/N.", "(41b) Consequently, C EXC =γ e0 N+ 4γ e1 T. (41c) Cost of Optical Ports for Thru and Add/Drop Traffic [0229] The total cost of OXCs using the network global expectation formalism may be characterized according to equation (42a), which follows: C OXC = c OXC N. (42a) An estimate of the current cost of high-speed optical switching engines may be characterized according to equation (42b), which follows: γ op ≈$2.5 K /port.", "(42b) Based on this cost structure and the architecture under consideration, which specifies that both through and termination-side traffic pass through the OXCs, the individual and mean OXC costs may be characterized according to equations (42c) and (42d), which follow: c oxc =γ op P, (42c) and so c oxc =γ op P .", "(42d) Substituting variables to obtain an expression that is independent of the demand model, the total cost of the OXCs may be characterized according to equation (42e), which follows: C OXC ( N )= c oxc N =2γ op D ( N )[(2+ κ ) h ], (42e) where D(N) is the number of two-way demands.", "[0235] As in the other examples, a cost structure for the optical cross-connect consisting of a startup term and a growth term may also be considered and may be characterized according to equation (42f), which follows: c oxc =γ o0 +γ o1 P (42f) In this case the mean and total cost of the OXCs may be characterized according to equations (42g) and ( 42 h ), which follow: c oxc =γ o0 +γ o1 P (42g) and C OXC ( N )= c oxc N=γ o0 N+ 2γ 01 D ( N )[(2+ κ ) h ].", "(42h) [0238] Summing the electronic and optical bandwidth management costs, results in equation (43), which follows: C BWM ( N,T )=(γ e0 +γ o0 ) N+ 4γ e1 T+ 2γ o1 D ( N )[(2+ κ ) h ].", "(43) Comparison of Costs for Example Node Architectures [0240] As an illustration of the application of the network global expectation model, the total costs for BWM for the two single-tier node architecture examples just described;", "namely electronic plus optical BWM and electronic-only BWM, are compared as a function of the number of nodes N and traffic T for fixed mean degree of node.", "The results of the calculations using the coarse cost structures for the EXC and OXC costs, equations (39b) and (42b), are graphed in FIG. 8 .", "[0241] FIG. 8 graphically depicts a plot of the total cost of bandwidth management using the combination of optical and electronic cross-connects compared to the total cost of bandwidth management using only an electronic cross-connect.", "The ratio is plotted as a function of the number of nodes, N, and two-way traffic, T. In the case of the optical and electronic architecture, it is assumed that all traffic follows through the optical switch fabric and additionally that all terminating traffic flows through the electronic switch fabric.", "The calculations performed and depicted in FIG. 8 are for uniform demand with restoration under the constraint δ =3.5.", "The cost structure (γ) used for the optical cross-connects and electronic cross-connects for this example are $2.5 K/port and $1 K/Gbps, respectively.", "It should be noted that these costs structures and values are rudimentary, intended to be illustrative, and should not be interpreted as definitive.", "[0242] The network global expectation model of the present invention may be used to identify the region of the network parameter space where optical layer cross-connects may be introduced in conjunction with electronic cross-connects, or IP Routers, to economic advantage.", "The model accounts not only for the different characters of the cost structures as a function of traffic, but also accounts for the changing ratio of add/drop to through traffic as the number of nodes and links change.", "It is observed that for fixed values of the number of nodes for N greater than 15 that the total cost of bandwidth management using the electronic and optical (E&O) architecture decreases and becomes less than the cost of the electronic (E)-only solution as the total traffic increases.", "This is attributed to the assumption that the cost of an optical switch port is independent of channel bit-rate while the cost of an electronic switch port is directly proportional to the channel bit-rate.", "It is also observed that for fixed total network traffic that the cost of the E&O solution increases and becomes more expensive than the E-only solution as the number of nodes is increased and the mean degree of the nodes is held constant.", "This is because the mean termination-to-termination traffic decreases as the number of nodes is increased for fixed mean degree of the nodes (see FIG. 4 ), and consequently below some channel bit-rate, the fixed cost of an optical switch port becomes more expensive than an electronic switch port.", "[0243] Of course, the details of the cost crossover depend upon the particulars of the technology price points (cost structure and coefficients), and consequently, the graph of FIG. 8 is intended only to demonstrate the capabilities and possibilities of the global expectation model and not to make a definitive recommendation.", "It should be noted that herein it has been implicitly assumed via the cost structures that the respective cross-connects technologies are capable of providing the required switch and backplane capacities.", "In the absence of more refined cost structures that account for these limitations, other equations and graphs of the model may be used, such the total number of required ports (equation (21b)) or the mean cross-connect traffic, to identify regions of the network traffic-node space that are beyond the capabilities of a particular architecture or technology.", "[heading-0244] Total Network Costs [0245] The total network cost may be computed by summing the cost for transmission and bandwidth management using the formulae derived herein.", "For completeness equation 4 may be characterized according to equation (44), which follows: C T =C TRANS +C BWM (44) [0246] Clearly, a useful attribute of the model is that the relative cost of transmission and bandwidth management can easily and quickly be determined.", "[0247] To illustrate the utility of the network global expectation model, FIG. 9 depicts a calculation of the total cost of a mesh network with uniform demand as a function of the number of nodes N and total traffic T. FIG. 9 graphically depicts a plot of the total cost of a mesh network with uniform demand as a function of the number of nodes N and total traffic T. The sum of transmission and bandwidth management equipment costs, C T (N,T), is graphed as a function of the number of nodes, N, and total two-way traffic, T using a contour plot.", "As in FIG. 8 , the calculations in FIG. 9 are for uniform demand with restoration under the constraint δ =3.5.", "The cost structures used for the optical line systems, electronic cross-connects, and optical cross-connects are $30/Gbps/km, $1 K/Gbps, and $2.5 K/port, respectively.", "Again, it should be noted that these cost structures and values are intended only to illustrate the capabilities and possibilities of the global expectation model of the present invention and should not be interpreted as definitive.", "[0248] The results of FIG. 9 are for the case where the nodal bandwidth manager consists of a combination of optical layer and electronic cross-connects and the geographic area corresponds to the continental U.S. In the accounting, equations (33) and (34), equations (39b) and (39c), and equations (42b) and (42c) were used for the cost structure of the transmission links, electronic cross-connects, and optical cross-connects, respectively.", "[0249] Among the features that may be observed by considering FIG. 9 is the impact of the cost of bandwidth management as the number of nodes increases.", "A qualitatively similar result is obtained for the case of electronic-only bandwidth management.", "Considering equation (22b) for total number of cross-connect ports and equation (30e) for the add/drop ratio, the large cost for large N may be interpreted to be a consequence of the single layer architecture.", "In effect, single-tier (flat) networks can not practically scale to very large number of nodes because as the number of nodes increases an increasing fraction of the traffic processed at each node is through traffic destined for other nodes.", "It is for this reason that the voice and packet networks are organized hierarchically based on geographic communities.", "[0250] The underlying phenomenon may also be the driving factor behind more broadly observed scaling behavior of networks and biological systems.", "Clearly there are performance and operational tradeoffs between single-tier and multi-tier networks, and network operators will adjust the number of nodes and architecture in the backbone depending upon the costs for transmission and bandwidth management;", "changing cross-connect, line-system, and technology price points;", "and the evolution of traffic demand.", "[heading-0251] Refinement of Cost Structure and Evolution of Network Cost [0252] In alternate embodiments of the present invention, the cost structure may be modified to account for the real-world implementation limits affecting maximum system capacities.", "Examples of such constraints are the maximum number of channels or wavelengths an optical line system is engineered for, or the maximum throughput of a switch fabric or backplane in the case of a cross-connect or router.", "Such hard bounds to network element capacity occur for any physical realization and have the effect of introducing quantum steps in the cost structure.", "When required capacities exceed the system capabilities, generally additional systems are deployed in parallel, and additional corresponding startup costs are incurred.", "Having developed a framework for the evaluation of the variances and distribution functions of key network variables earlier herein, a foundation has been provided to estimate the number of additional systems that are required given the network requirements and system bounds.", "Note too that in some instances the result of introducing these additional systems is to effectively increase the number of links or nodes of the network.", "[0253] Furthermore, in alternate embodiment of the present invention, the network global expectation model of the present invention may be used for sensitivity analyses of the dependency of requirements and costs upon primary and secondary network and network element variables.", "The network global expectation model may also be used to compute the constituent and total network costs as a function of time.", "This requires only a model for how the total network traffic, number of nodes and links, and technology costs are expected to change.", "Some models for estimating how the total network traffic, number of nodes and links, and technology costs are expected to change are known in the art.", "[0254] As previously mentioned, although the concepts of the present invention are being described herein with respect to communication networks, the concepts of the present invention may be applied to other networks and systems, such as power and commodity distribution and transportation systems.", "[0255] The operations of the present invention may be performed by a general purpose computer that is programmed to perform various operational calculations and functions in accordance with the present invention.", "In addition, the calculations and functions of the present invention can be implemented in hardware, for example, as an application specified integrated circuit (ASIC).", "As such, the process steps described herein are intended to be broadly interpreted as being equivalently performed manually by a user or by software, hardware, or a combination thereof.", "[0256] Furthermore, in an alternate embodiment of the present invention, the calculations, equations, and operations of the present invention herein may be loaded into the memory of a general purpose computer, along with instructions, for performing the operations and functions of the present invention.", "As such, the present invention comprises a computer program product.", "[0257] While the forgoing is directed to various embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof.", "As such, the appropriate scope of the invention is to be determined according to the claims, which follow." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/897,752, filed Jan. 26, 2007. The entire contents of that application are incorporated herein by reference. INTRODUCTION [0002] An embodiment of the present invention (referred to herein for convenience as the SPECTRUM US Index”) is an index that preferably is positioned as a “US equity large cap” investment, and which aims to outperform the S&P 500 Total Return Index (“SPTR”). [0003] Preferably, in this embodiment, the SPECTRUM US Index takes an innovative sectorial allocation approach by applying the methodology of “momentum investing” to the ten component sub-Indices of the S&P 500 index. According to this methodology, the SPECTRUM US Index is rebalanced daily to account for the different performances of the sub-indices relative to the SPTR. On each day, two steps are performed to compute new sub-index weights. [0004] In the first step, sub-indices that perform well relative to the SPTR (on the basis of the semi-annual performance of a semi-annual moving average) have their relative weight in the SPECTRUM US Index increased, while sub-indices that perform poorly have their relative weight reduced. [0005] In the second step, a “benchmarking” methodology is applied to make SPECTRUM US an efficient tracker of the SPTR: the weights are modified according to correlations between each sub-index and the SPTR. Poorly correlated sub-indices may see their weight reduced, while highly correlated indices may see their weight increased. In other words, over or under weighting of each sub-index will be approximately proportional to a 6 month correlation of its daily returns with SPTR's daily returns. Once the new weights are computed, they are compared to the current weights. If the new weights are sufficiently different from the current weights, e.g., that they exceed a threshold difference, the SPECTRUM US Index is rebalanced: the current weights are reset to the new computed weights. Otherwise, the current weights are left unchanged. [0006] The criteria for changing weights preferably are determined by mathematical formulae described herein. OVERVIEW OF CERTAIN EMBODIMENTS [0007] 1. SPECTRUM US Index [0008] The SPECTRUM US Index is an index that tracks the value of a portfolio. An embodiment is based upon a portfolio composed of the ten S&P 500 Sub-Indices (“the Sub-Indices”) representing the ten Level 1 GICS Sectors (see TABLE 1 below): [0000] TABLE 1 S&P 500 Consumer Discretionary Index S&P 500 Consumer Staples Index S&P 500 Energy Index S&P 500 Financials Index S&P 500 Health Care Index S&P 500 Industrials Index S&P 500 Materials Index S&P 500 Telecommunication Index S&P 500 Information Technology Index S&P 500 Utilities Index [0009] A Calculation Agent calculates and rebalances daily the SPECTRUM US Index based on the allocation methodology described below. [0010] 2. Sectors Assigned to the SPECTRUM US Index S&P uses the Global Industry Classification Standard (“GICS”), an industry model recognized by market participants worldwide, as the structure for all S&P indices. Investors use S&P sector indices across all areas of the equity markets—including asset management, sector research, portfolio strategy, peer analysis, and client account reporting. The use of GICS enables market participants to identify and analyze a customized group of companies from a common global standard. More detailed information published by S&P on understanding the sectors underlying the sub-indices and the GICS standard is available at S&P's website (standardandpoors.com). [0012] 3. Construction of the SPECTRUM US Index [0013] The SPECTRUM US Index preferably is constructed using a hardwired formula-based selection and rebalancing methodology that assigns specific weights to each of the underlying Sub-Indices and recalculates such weights on a daily basis. [0014] Sub-Indices Values [0015] The SPECTRUM US Index preferably is a Total Return Index, which means that the distributions paid by any of the Sub-Indices are continuously re-invested in the SPECTRUM US Index. A preferred process of dividend reinvestment is detailed below in the section entitled “Sectors Total Return Level Calculation.” [0016] Index Calculation [0017] In an embodiment, the SPECTRUM US Index is calculated by reference to Sectors Total Return Levels and Sector Weights, which preferably are derived from the Allocation Methodology (see below). The SPECTRUM US Index calculation is explained below in the section entitled “Index Calculation Methodology.” The Index is rebalanced on each Reallocation Date, with new weights being assigned to each of the Sub-Indices, when a Reallocation Event is deemed to occur as determined by a Calculation Agent (see the section below entitled “Sector Weight Determination”). [0018] Allocation Methodology [0019] Exemplary Allocation Methodology is described in detail below. A brief overview is included here: [0020] A. How the Weights of each Sub-Index are Calculated [0021] On any Index Calculation Day, Target Weights will be calculated for each of the Sub-Indices. These Target Weights are factoring in trend indicators so that out-performing sectors have a greater Target Weight than under-performing ones. On each Reallocation Date, the SPECTRUM US Index will be rebalanced, with the weight of each Sub-Index being set equal to its Target Weight on the day the Reallocation Event occurred. [0022] B. When SPECTRUM US Index is Rebalanced [0023] The Target Weights, calculated on each Index Calculation Day, factor in the latest trend indicators available. The SPECTRUM US Index allocation must be close enough to this target allocation, so that a Reallocation Event is deemed to occur when the set of Weights used in the SPECTRUM US Index is different enough from the set of Target Weights. To quantify this difference, the Distance is calculated on each Index Calculation Day. [0024] Additions/Deletions of Sub-Indices [0025] The composition of the Sub-Indices that underlie the SPECTRUM US Index will be constant, provided that, if S&P adds or deletes a certain Sub-Index from its portfolio of indices, the SPECTRUM US Index shall be modified accordingly. However, the Allocation Methodology preferably shall remain the same. [0026] Index Level: The SPECTRUM US Index Level will be determined by the Calculation Agent by reference to the value of a Portfolio giving exposure to a basket of 10 S&P 500 Sub-Indices as described herein. The SPECTRUM US Index Level is a function of 10 Sector Total Return Levels, which are calculated below in the section entitled “Sector Total Return Level Calculation.” [0000] TABLE 2 Sector S&P 500 Sub-Indices Consumer Discretionary S&P 500 Consumer Discretionary Index Consumer Staples S&P 500 Consumer Staples Index Energy S&P 500 Energy Index Financial S&P 500 Financials Index Healthcare S&P 500 Health Care Index Industrial S&P 500 Industrials Index Materials S&P 500 Materials Index Telecommunication S&P 500 Telecommunication Index Technology S&P 500 Information Technology Index Utilities S&P 500 Utilities Index [0027] Allocation Methodology: The SPECTRUM US Index Allocation may be modified from the Initial Calculation Date in accordance with the Allocation Methodology described below. [0028] Exemplary Terms: [0029] Calculation Agent: Standard & Poor's [0030] Initial Index Calculation Day: 2 nd Jan. 1991 [0031] Index Calculation Day: New York, Sector Calculation Day [0032] Initial Sectors Calculation Day: 2 nd Jan. 1990 [0033] Sector Calculation Day: New York and any day on which a Close Value is published for the 10 above listed S&P 500 Sub-Indices. [0034] An embodiment of the invention is directed to a method for providing a securities index, that comprises identifying a first index having a plurality of sub-components; constructing a portfolio having a plurality of sub-portfolios, each sub-portfolio containing holdings corresponding to one of said sub-components, and each sub-portfolio having a corresponding initial weight with respect to said portfolio; defining a second index corresponding to performance of said portfolio; calculating performance for each of said sub-components relative to performance of said first index; calculating a correlation of each of said sub-components with said first index; and periodically rebalancing said portfolio by increasing weights of sub-portfolios corresponding to sub-components out-performing said first index and decreasing weights of sub-portfolios corresponding to sub-components under-performing said first index; except that for sub-components having the respective calculated correlation differing with said first index, corresponding sub-portfolios do not have weight increased. Some embodiments of the invention also include: providing one or more exchange traded notes based on said second index, exchange traded notes do not pay interest during the term of said notes, said first index is a total return index, said second index is a total return index, said portfolio is rebalanced daily, said first index is the S&P 500 Total Return Index, and/or each of said sub-components receives a weight increase or decrease only when said weight increase or decrease when compared to a prior weight for each of said sub-components exceeds a specified threshold value. [0035] Another embodiment of the invention is directed to software stored on a computer readable medium comprising: software for identifying a first index having a plurality of sub-components; software for constructing a portfolio having a plurality of sub-portfolios, each sub-portfolio containing holdings corresponding to one of said sub-components, and each sub-portfolio having a corresponding initial weight with respect to said portfolio; software for defining a second index corresponding to performance of said portfolio; software for calculating performance for each of said sub-components relative to performance of said first index; software for calculating a correlation of each of said sub-components with said first index; and software for periodically rebalancing said portfolio by increasing weights of sub-portfolios corresponding to sub-components out-performing said first index and decreasing weights of sub-portfolios corresponding to sub-components under-performing said first index; except that for sub-components having the respective calculated correlation differing with said first index, corresponding sub-portfolios do not have weight increased. Other embodiments of the invention include: providing one or more exchange traded notes based on said second index, said exchange traded notes do not pay interest during the term of said notes, said first index is a total return index, said second index is a total return index, said portfolio is rebalanced daily, said first index is the S&P 500 Total Return Index, and/or each of said sub-components receives a weight increase or decrease only when said weight increase or decrease when compared to a prior weight for each of said sub-components exceeds a specified threshold value. BRIEF DESCRIPTION OF THE DRAWINGS [0036] FIG. 1 depicts a computer system for implementing an embodiment of the invention. [0037] FIG. 2 depicts a flowchart of a method according to an embodiment of the invention. DETAILED DESCRIPTION [0038] I. Sectors Total Return Level Calculation [0039] Summary: The purpose of this section is to describe, for an exemplary embodiment, the Sector Total Return Levels that will be representative of each Level 1 GICS Sector. Each Sector is associated with an S&P 500 Sub-Index. On each Sector Calculation Day, the Sector Total Return Levels are calculated by reinvesting the dividends paid by the relevant S&P 500 Sub-Index on this Index Calculation Day (1). [0040] Sector Description: Each Level 1 GICS sector is represented by an S&P 500 Sub-Index: [0000] TABLE 3 S&P 500 Sub- Index i Bloomberg I Sector i S&P 500 Sub-Index i Ticker 1 Consumer S&P 500 Consumer S5COND Index Discretionary Discretionary Index 2 Consumer Staples S&P 500 Consumer Staples S5CONS Index Index 3 Energy S&P 500 Energy Index S5ENRS Index 4 Financial S&P 500 Financials Index S5FINL Index 5 Healthcare S&P 500 Health Care Index S5HLTH Index 6 Industrial S&P 500 Industrials Index S5INDU Index 7 Materials S&P 500 Materials Index S5MATR Index 8 Telecommunication S&P 500 S5TELS Index Telecommunication Index 9 Technology S&P 500 Information S5INFT Index Technology Index 10 Utilities S&P 500 Utilities Index S5UTIL Index [0041] Sector Level On the Initial Sectors Calculation Day, the Initial Sector i Total Return Level will be determined as follows, for i=1 . . . 10: [0000] Sector 0 i =100 [0042] On each Index Calculation Day, the Sector i Total Return Level will be determined as follows, for i=1 . . . 10: [0000] Sector t i = Sector t - 1 i · SubIndex t i + SubIndexDiv t i SubIndex t - 1 i ( 1 ) [0043] Where: [0044] Sector i t−1 is the Sector i Total Return Level as of the Sectors Calculation Day preceding t. [0045] SubIndex i t is the S&P 500 Sub-Index i Close Level as of Sectors Calculation Day t, as published on the above relevant Bloomberg Page. [0046] SubIndex i t−1 is the S&P 500 Sub-Index i Close Level as of the Sectors Calculation Day preceding t, as published on the above relevant Bloomberg Page. [0047] SubIndexDiv i t is the S&P 500 Sub-Index i Net Dividend detached on Sectors Calculation Day t. [0048] II. Index Calculation Methodology [0049] Summary: The purpose of this section is to describe, for an exemplary embodiment, SPECTRUM US Index Level in reference to the various Sector Total Returns, as described in the preceding section, and the various Sector Weights, as described in the following section. As detailed in the section entitled “Allocation Methodology,” the SPECTRUM US Index preferably is rebalanced only on Reallocation Dates. Consequently, on each Index Calculation Date, the SPECTRUM US Index level will be calculated in reference to the SPECTRUM US Index Level as of the strictly preceding Reallocation Date, and the Sector Weights as determined on this Reallocation Date. The Performance of the SPECTRUM US Index since the strictly preceding Reallocation Date is equal to the sum of the Sector Total Return Level performances since the last Reallocation Date weighted by the Sector Weights determined on this Reallocation Date (see (2) below). [0050] Index Level: On the Initial Index Calculation Day, the Initial Index Level will be determined as follows: [0000] Index 0 =100 [0051] On each Index Calculation Day t, SPECTRUM US Index Level will be determined as follows: [0000] Index t = Index r · ∑ i = 1 10   ( W r i · Sector t 1 Sector r i ) ( 2 ) [0052] Where: [0053] Index r is Index Level as of the Reallocation Date strictly preceding SPECTRUM US Index Calculation Day t. [0054] The Initial Index Calculation Day is a Reallocation Date. [0055] W r i is Sector i Weight in SPECTRUM US Index as of the Reallocation Date strictly preceding SPECTRUM US Index Calculation Day t, as defined in the next section (“Allocation Methodology”). [0056] Sector t i is Sector i Total Return Level as of Index Calculation Day t, as defined in the preceding section (“Sectors Total Return Level Calculation”). [0057] Sector r i is Sector i Total Return Level as of the Reallocation Date strictly preceding SPECTRUM US Index Calculation Day t. [0058] III. Allocation Methodology [0059] Summary: The purpose of this section is to describe, for an exemplary embodiment, SPECTRUM US Index Allocation between the 10 Sectors used in an embodiment. [0060] How the Weights of the Sub-Indices are Calculated [0061] On any Index Calculation Day, Target Weights will be calculated for each of the Sub-Indices. This is the purpose of the Section Target Weight Determination. On any Index Calculation Day, each Sector is given a Target Weight, in accordance with the following procedure: [0062] This methodology is based on trend following. Using the sliding average of the close levels for each Sub-index and SPTR permits determination and comparison of the trends between these sectors and the S&P 500 Total Return. The Average Level is defined as the average of the Close Levels over the last 120 Sector Calculation Days. See (6) & (8) below. [0063] Then the trend of each sector and SPTR will be quantified by calculating the Sector and SPTR Performances. These Performances will represent the trend in the rest of this methodology. They are calculated as the Annualized Performances over the last 120 Sector Calculation Days of the Average Levels. See (5) & (7) below. [0064] These Performances, representing trends, will then be used in the calculation of the Sector Coefficients (4). The goals of this formula are: [0065] (a) To give a greater Coefficient to Sectors showing a greater Performance than the S&P 500 Total Return's Performance, and conversely (i.e., a smaller coefficient is given to Sectors showing a lesser Performance). Sectors out-performing SPTR will be given a Sector Coefficient greater than 1, out-performance being defined as a Performance greater than SPTR's Performance. Sector under-performing SPTR will be given a Sector Coefficient lower than 1, so that out-performing Sectors, in the sense of the indicators used in the methodology, will be over-weighted in SPECTRUM US Index, and conversely (under-performing Sectors are under-weighted). [0066] (b) To control and to limit the over-weighting of Sectors showing a poor correlation with the S&P 500 Total Return. Indeed, an excessive over-weighting of Sectors poorly correlated to SPTR would result in SPECTRUM US Index itself showing a poor correlation with the S&P 500 Total Return. As an example, Sectors anti-correlated with SPTR (i.e., showing a correlation with SPTR negative or equal to zero) will be given a Sector Coefficient of 1. Over or under weighting of each sub-index may be approximately proportional to a 6 month correlation of its daily returns with SPTR's daily returns so that sub-indices well correlated with SPTR will be over-weighted. The Sector Coefficients are not Weights. Indeed, their sum is likely to be different than 1. The Sector Target Weights are calculated by normalizing the Sector Coefficients (see (3) below), which means that the Sector Target Weights are proportional to the Sector Coefficients and that their sum is equal to 1. [0067] When the SPECTRUM US Index is Rebalanced [0068] The Target Weights are calculated on a daily basis. They factor in the latest information for implementing a momentum strategy, given the trend indicators that are used. However, SPECTRUM US Index preferably is not rebalanced every day. It is rebalanced only when the Target Allocation is deemed different enough from the Allocation which was used in the SPECTRUM US Index since the latest Reallocation Date. In order to quantify this difference and determine the occurrence of a Reallocation Event, the following procedure is applied on a daily basis: [0069] (i) The Target Allocation and the Allocation can be represented by two vectors, made of the 10 Sector Target Weights, for the Target Allocation, and the 10 Sector weights for the Allocation in place in SPECTRUM US Index. The Distance, as calculated in (10) is a positive number that quantifies how different these two vectors are, and therefore quantifies the difference between Target and Sector Weights. [0070] For example, if, for any given Sector, the Sector Target Weight is equal to the Sector Weight, the Distance will be equal to zero. For any particular Sector, the greater the difference between the Target Sector Weight and the Sector Weight, the greater the Distance. [0071] (ii) A Reallocation Event is deemed to occur if the Distance is strictly greater than 20%. [0072] (iii) Then, SPECTRUM US Index Rebalancing will take place two Index Calculation Days after the occurrence of a Reallocation Event (see (9) below). [0073] IV. Sector Target Weights Determination [0074] Target Weights: On each Index Calculation Day, the Sector i Target Weight will be determined as follows, for i=1 . . . 10: [0000] Wtg t i = Coeff t i ∑ i = i 10   Coeff t i ( 3 ) [0075] Where: Coeff t i is Sector i Target Coefficient as of Index Calculation Day t. [0076] Target Coefficients: On each Index Calculation Day, the Sector i Target Coefficient will be determined as follows, for i=1 . . . 10: [0000] Coeff t i = Max [ 0 , 1 + Max  ( ρ t i , 0  % ) × 150  % × Perf t i - Perf t SPTR 1 10  ∑ j = 1 10  | Perf t i - Perf t SPTR | ] ( 4 ) [0077] Where: [0078] ρ t i is Sector i Correlation as of Index Calculation Day t; [0079] Perf t i is Sector i Performance as of Index Calculation Day t; and [0080] Perf t SPTR is SPTR Performance as of Index Calculation Day t. [0081] Sector Correlation: The Sector i Correlation as of Index Calculation Day t, ρ t i , will be determined by the Calculation Agent, for i=1 . . . 10, as the Correlation of the Daily Returns of Sector i with the Daily Returns of SPTR, over a period of 120 Index Calculation Days ending on Index Calculation Day t. [0082] Sector Performance: On each Index Calculation Day, the Sector i Performance will be determined as follows, for i=1 . . . 10: [0000] Perf t i = ( Average t i Average t - 120 i ) 2 - 1 ( 5 ) [0083] Where: [0084] Average t i is Sector i Average Level as of Index Calculation Day t; and [0085] Average i t−120 is Sector i Average Level as of the Sector Calculation Day which 120 Sector Calculation Days before Index Calculation Day t. [0086] Sector Average Level: On each Sectors Calculation Day, the Sector i Average Level will be determined as follows, for i=1 . . . 10: [0000] Average t i = 1 120  ∑ s = 0 119   Sector t - s i ( 6 ) [0087] Where: [0088] Sector i t−s is Sector i Total Return Level as of the Sector Calculation Day which is s Sector Calculation Days before Sector Calculation Day t. [0089] SPTR Performance: On each Index Calculation Day, the SPTR Performance will be determined as follows: [0000] Perf t SPTR = ( Average t SPTR Average t - 120 SPTR ) 2 - 1 ( 7 ) [0090] Where: [0091] Average t SPTR is SPTR Average Level as of Index Calculation Day t; and [0092] Average SPTR t−120 is SPTR Average Level as of the Sector Calculation Day which 120 Sector Calculation Days before Sector Calculation Day t. [0093] SPTR Average Level: On each Index Calculation Day, the SPTR Average Level will be determined as follows: [0000] Average t SPTR = 1 120  ∑ s = 0 119   SPTR t - s ( 8 ) [0094] Where: SPTR t−s is SPTR Close Level as of the Sector Calculation Day which is s Sector Calculation Days before Sector Calculation Day t. [0095] V. Sector Weights Determination [0096] Sector Weights On the Initial Index Calculation Day, the Initial Sector i Weights will be determined as follows, for i=1 . . . 10: [0000] W 0 i =Wtg 0 i [0097] Where: [0098] Wtg i 0 is Sector i Target Weight as of the Initial Index Calculation Date. [0099] The Initial Index Calculation Day preferably is a Reallocation Date. [0100] On each Index Calculation Day t, following the determination of the Sector Target Weights, the Calculation Agent will determine SPECTRUM US Index Allocation between the Sectors as follows: [0101] If t+1 is a Reallocation Date, then t+2 won't be a Reallocation Date. [0102] If t+1 is not a Reallocation Date, and Distance t ≦20%, then t+2 won't be a Reallocation Date. [0000] If t+1 is not a Reallocation Date, and Distance t >20%, then a Reallocation Event is deemed to occur and t+2 will be a Reallocation Date: for i=1 . . . 10, W t+2 i =Wtg t i   (9) [0103] Where: [0104] t+1 is Index Calculation Day which is I Index Calculation Day after Index Calculation Day t. [0105] t+2 is Index Calculation Day which is 2 Index Calculation Days after Index Calculation Day t. [0106] Distance t is the Distance as of Index Calculation Day t. [0107] Distance: On each Index Calculation Day t, the Distance will be calculated as follows: [0000] Distance t = ∑ t = 1 10   ( W r i - Wtg t i ) 2 ( 10 ) [0108] Where: [0109] W t i is Sector i Weight as of the Reallocation Date strictly preceding SPECTRUM US Index Calculation Day t; and [0110] Wtg t i is Sector i Target Weight as of Index Calculation Day t. [0111] Exemplary Terms for Exchange Traded Notes [0112] Exemplary terms for Exchange Traded Notes linked to the SPECTRUM US Sector Momentum Index are provided below. [0113] The Exchange-Traded Notes due [], 2016 (the “Securities”) are linked to the SPECTRUM US Sector Momentum Index, do not guarantee any return of principal at maturity, and do not pay any interest during their term. Instead, a purchaser will receive a cash payment at maturity or early redemption based on the performance of the S&P Custom/BNP Paribas—SPECTRUM US Sector Momentum Index less an investor fee. The principal terms of the Securities are as follows: [0114] Issuer: [Issuer] [0115] Underlying Index The return on the Securities is linked to the performance of the SPECTRUM US Sector Momentum Index (the “Index”). The Index is positioned as a “U.S. equity large cap” investment. The Index is published under the symbol <Index>. [0116] Payment at Maturity: If a purchaser holds his or her Securities to maturity, the purchaser will receive a cash payment at maturity equal to the principal amount of the held Securities limes the index factor on the final valuation date limes the fee factor on the final valuation date. [0117] Secondary Market: The Securities are listed on the New York Stock Exchange under the ticker symbol “[Securities Symbol]”. If an active secondary market in the Securities develops, we expect that investors will purchase and sell the Securities primarily in this secondary market. [0118] Early Redemption: Subject to the notification and minimum amount requirements described below, a purchaser may redeem his Securities on any redemption date during the term of the Securities. If the purchaser redeems his Securities, he will receive a cash payment in an amount equal to the weekly redemption value, which is the principal amount of his Securities times the index factor on the applicable valuation date limes the fee factor on the applicable valuation date. The purchaser must redeem at least 250,000 Securities (a principal amount equal 1-NY/2266897.2 to at least $2.5 million) at one time in order to exercise his right to redeem his Securities on any redemption date. [0119] Redemption Mechanics: In order to redeem his Securities on a redemption date, a purchaser must deliver a notice of redemption via email by no later than 11:00 a.m. New York City time on the business day prior to the applicable valuation date. [0120] Valuation Date: Valuation date means each [Thursday] from [], 2007 to [], 2017 inclusive or, if such date is not a trading day, the next succeeding trading day, not to exceed five business days. We refer to [Thursday], [], 2017, as the “final valuation date.” [0121] Redemption Date: A redemption date is the third business day following a valuation date (other than the final valuation date). The final redemption date will be the third business day following the valuation date that is immediately prior to the final valuation date. [0122] Inception Date: [], 2007. [0123] Index Factor: The index factor on any given day will be equal to the closing value of the Index on that day divided by the initial index level. The initial index level is the closing value of the Index on the inception date. [0124] Fee Factor: The fee factor is equal to one minus the investor fee. The investor fee is equal to 0.75% times the number of calendar days elapsed from the inception date up to and including the applicable valuation date divided by 365. [0125] Because the investor fee and the fee factor reduce the amount of return at maturity or upon redemption, the value of the Index must increase significantly in order for a purchaser to receive at least the principal amount of your investment at maturity or upon redemption. If the value of the Index decreases or does not increase sufficiently, a purchaser will receive less than the principal amount of his investment at maturity or upon redemption. [0126] Trading Day: A trading day is a day on which (i) the value of the Index is calculated and published, (ii) trading is generally conducted on the New York Stock Exchange, and (iii) trading is generally conducted on the markets on which the futures contracts underlying the Index are traded, in each case as determined by the calculation agent in its sole discretion. [0127] Valuation of the Securities [0128] The market value of the Securities will be affected by several factors. We expect that generally the value of the Index on any day will affect the market value of the Securities more than any other factors. Other factors that may influence the market value of the Securities include, but are not limited to, supply and demand for the Securities, the volatility of the Index, the levels of the Sub-indices, the market price of the Index Components, prevailing interest rates, the volatility of securities markets, economic, financial, political, regulatory, geographical, biological or judicial events that affect the value of the Index or the market price of Index Components, the general interest rate environment, as well as the perceived creditworthiness of AIG. Indicative Value [0129] An intraday “indicative value” meant to approximate the intrinsic economic value of the Securities will be calculated: [0000] Indicative Value=Principal Amount per Security×(Current Index Level/Initial Index Level)×Current Fee Factor [0130] where: Principal Amount per Security=$10; Current Index Level=The most recent published level of the Index as reported by the AIG-FP; Initial Index Level=The level of Index on the inception date; and Current Fee Factor=The most recent daily calculation of the fee factor with respect to your Securities, determined as described above (which, during any trading day, will be the fee factor determined on the preceding calendar day). [0131] The indicative value will be derived from sources deemed reliable. [0132] Inventions described herein may be automated and used in the exemplary system of FIG. 1 . As shown, client computers 200 communicate via network 210 with a central server 230 which is coupled to one or more databases 240 , one or more processors 250 , and software 260 . Other components and combinations of components may also be used to support processing and calculations described herein as will be evident to one of skill in the art. Server 230 facilitates communication of returns data from a database 240 to and from clients 200 . Processor 250 provides calculations relevant to calculations described herein. Software 260 can be installed locally at a client 200 and/or centrally supported for facilitating calculations and applications. For example, software 260 may be used in embodiments where a threshold, e.g., for weights is established. [0133] Embodiments of the invention may be provided according to the flowchart of FIG. 2 . As shown, a first index having sub components is identified, step 310 . A portfolio is constructed having sub-portfolios, step 320 . A second index is defined corresponding to performance of the portfolio, step 330 . A performance of each of the sub-components relative to performance of the first index is calculated, step 340 . A correlation of each of the sub components relative to the first index is calculated, step 350 . The portfolio is rebalanced, step 360 . [0134] Although certain embodiments have been described in detail herein, it will be apparent to those skilled in the relevant art that various modifications, additions, substitutions and the like can be made without departing from the scope of the invention as defined in the following claims.
A securities index is provided by identifying a first index that has a plurality of sub-components; constructing a portfolio that has a plurality of sub-portfolios, each sub-portfolio containing holdings corresponding to one of the index sub-components, and each sub-portfolio having a corresponding initial weight with respect to the portfolio. A second index is defined that corresponds to performance of the portfolio. Performance for each of said sub-components relative to performance of said first index is calculated. A correlation of each of said sub-components with said first index is calculated. The portfolio is periodically rebalanced by increasing weights of sub-portfolios corresponding to sub-components that out-perform the first index and decreasing weights of sub-portfolios corresponding to sub-components under-performing the first index; except that for sub-components having the respective calculated correlation differing with the first index, corresponding sub-portfolios do not have weight increased.
Provide a concise summary of the essential information conveyed in the given context.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/897,752, filed Jan. 26, 2007.", "The entire contents of that application are incorporated herein by reference.", "INTRODUCTION [0002] An embodiment of the present invention (referred to herein for convenience as the SPECTRUM US Index”) is an index that preferably is positioned as a “US equity large cap”", "investment, and which aims to outperform the S&P 500 Total Return Index (“SPTR”).", "[0003] Preferably, in this embodiment, the SPECTRUM US Index takes an innovative sectorial allocation approach by applying the methodology of “momentum investing”", "to the ten component sub-Indices of the S&P 500 index.", "According to this methodology, the SPECTRUM US Index is rebalanced daily to account for the different performances of the sub-indices relative to the SPTR.", "On each day, two steps are performed to compute new sub-index weights.", "[0004] In the first step, sub-indices that perform well relative to the SPTR (on the basis of the semi-annual performance of a semi-annual moving average) have their relative weight in the SPECTRUM US Index increased, while sub-indices that perform poorly have their relative weight reduced.", "[0005] In the second step, a “benchmarking”", "methodology is applied to make SPECTRUM US an efficient tracker of the SPTR: the weights are modified according to correlations between each sub-index and the SPTR.", "Poorly correlated sub-indices may see their weight reduced, while highly correlated indices may see their weight increased.", "In other words, over or under weighting of each sub-index will be approximately proportional to a 6 month correlation of its daily returns with SPTR's daily returns.", "Once the new weights are computed, they are compared to the current weights.", "If the new weights are sufficiently different from the current weights, e.g., that they exceed a threshold difference, the SPECTRUM US Index is rebalanced: the current weights are reset to the new computed weights.", "Otherwise, the current weights are left unchanged.", "[0006] The criteria for changing weights preferably are determined by mathematical formulae described herein.", "OVERVIEW OF CERTAIN EMBODIMENTS [0007] 1.", "SPECTRUM US Index [0008] The SPECTRUM US Index is an index that tracks the value of a portfolio.", "An embodiment is based upon a portfolio composed of the ten S&P 500 Sub-Indices (“the Sub-Indices”) representing the ten Level 1 GICS Sectors (see TABLE 1 below): [0000] TABLE 1 S&P 500 Consumer Discretionary Index S&P 500 Consumer Staples Index S&P 500 Energy Index S&P 500 Financials Index S&P 500 Health Care Index S&P 500 Industrials Index S&P 500 Materials Index S&P 500 Telecommunication Index S&P 500 Information Technology Index S&P 500 Utilities Index [0009] A Calculation Agent calculates and rebalances daily the SPECTRUM US Index based on the allocation methodology described below.", "[0010] 2.", "Sectors Assigned to the SPECTRUM US Index S&P uses the Global Industry Classification Standard (“GICS”), an industry model recognized by market participants worldwide, as the structure for all S&P indices.", "Investors use S&P sector indices across all areas of the equity markets—including asset management, sector research, portfolio strategy, peer analysis, and client account reporting.", "The use of GICS enables market participants to identify and analyze a customized group of companies from a common global standard.", "More detailed information published by S&P on understanding the sectors underlying the sub-indices and the GICS standard is available at S&P's website (standardandpoors.com).", "[0012] 3.", "Construction of the SPECTRUM US Index [0013] The SPECTRUM US Index preferably is constructed using a hardwired formula-based selection and rebalancing methodology that assigns specific weights to each of the underlying Sub-Indices and recalculates such weights on a daily basis.", "[0014] Sub-Indices Values [0015] The SPECTRUM US Index preferably is a Total Return Index, which means that the distributions paid by any of the Sub-Indices are continuously re-invested in the SPECTRUM US Index.", "A preferred process of dividend reinvestment is detailed below in the section entitled “Sectors Total Return Level Calculation.”", "[0016] Index Calculation [0017] In an embodiment, the SPECTRUM US Index is calculated by reference to Sectors Total Return Levels and Sector Weights, which preferably are derived from the Allocation Methodology (see below).", "The SPECTRUM US Index calculation is explained below in the section entitled “Index Calculation Methodology.”", "The Index is rebalanced on each Reallocation Date, with new weights being assigned to each of the Sub-Indices, when a Reallocation Event is deemed to occur as determined by a Calculation Agent (see the section below entitled “Sector Weight Determination”).", "[0018] Allocation Methodology [0019] Exemplary Allocation Methodology is described in detail below.", "A brief overview is included here: [0020] A. How the Weights of each Sub-Index are Calculated [0021] On any Index Calculation Day, Target Weights will be calculated for each of the Sub-Indices.", "These Target Weights are factoring in trend indicators so that out-performing sectors have a greater Target Weight than under-performing ones.", "On each Reallocation Date, the SPECTRUM US Index will be rebalanced, with the weight of each Sub-Index being set equal to its Target Weight on the day the Reallocation Event occurred.", "[0022] B. When SPECTRUM US Index is Rebalanced [0023] The Target Weights, calculated on each Index Calculation Day, factor in the latest trend indicators available.", "The SPECTRUM US Index allocation must be close enough to this target allocation, so that a Reallocation Event is deemed to occur when the set of Weights used in the SPECTRUM US Index is different enough from the set of Target Weights.", "To quantify this difference, the Distance is calculated on each Index Calculation Day.", "[0024] Additions/Deletions of Sub-Indices [0025] The composition of the Sub-Indices that underlie the SPECTRUM US Index will be constant, provided that, if S&P adds or deletes a certain Sub-Index from its portfolio of indices, the SPECTRUM US Index shall be modified accordingly.", "However, the Allocation Methodology preferably shall remain the same.", "[0026] Index Level: The SPECTRUM US Index Level will be determined by the Calculation Agent by reference to the value of a Portfolio giving exposure to a basket of 10 S&P 500 Sub-Indices as described herein.", "The SPECTRUM US Index Level is a function of 10 Sector Total Return Levels, which are calculated below in the section entitled “Sector Total Return Level Calculation.”", "[0000] TABLE 2 Sector S&P 500 Sub-Indices Consumer Discretionary S&P 500 Consumer Discretionary Index Consumer Staples S&P 500 Consumer Staples Index Energy S&P 500 Energy Index Financial S&P 500 Financials Index Healthcare S&P 500 Health Care Index Industrial S&P 500 Industrials Index Materials S&P 500 Materials Index Telecommunication S&P 500 Telecommunication Index Technology S&P 500 Information Technology Index Utilities S&P 500 Utilities Index [0027] Allocation Methodology: The SPECTRUM US Index Allocation may be modified from the Initial Calculation Date in accordance with the Allocation Methodology described below.", "[0028] Exemplary Terms: [0029] Calculation Agent: Standard &", "Poor's [0030] Initial Index Calculation Day: 2 nd Jan. 1991 [0031] Index Calculation Day: New York, Sector Calculation Day [0032] Initial Sectors Calculation Day: 2 nd Jan. 1990 [0033] Sector Calculation Day: New York and any day on which a Close Value is published for the 10 above listed S&P 500 Sub-Indices.", "[0034] An embodiment of the invention is directed to a method for providing a securities index, that comprises identifying a first index having a plurality of sub-components;", "constructing a portfolio having a plurality of sub-portfolios, each sub-portfolio containing holdings corresponding to one of said sub-components, and each sub-portfolio having a corresponding initial weight with respect to said portfolio;", "defining a second index corresponding to performance of said portfolio;", "calculating performance for each of said sub-components relative to performance of said first index;", "calculating a correlation of each of said sub-components with said first index;", "and periodically rebalancing said portfolio by increasing weights of sub-portfolios corresponding to sub-components out-performing said first index and decreasing weights of sub-portfolios corresponding to sub-components under-performing said first index;", "except that for sub-components having the respective calculated correlation differing with said first index, corresponding sub-portfolios do not have weight increased.", "Some embodiments of the invention also include: providing one or more exchange traded notes based on said second index, exchange traded notes do not pay interest during the term of said notes, said first index is a total return index, said second index is a total return index, said portfolio is rebalanced daily, said first index is the S&P 500 Total Return Index, and/or each of said sub-components receives a weight increase or decrease only when said weight increase or decrease when compared to a prior weight for each of said sub-components exceeds a specified threshold value.", "[0035] Another embodiment of the invention is directed to software stored on a computer readable medium comprising: software for identifying a first index having a plurality of sub-components;", "software for constructing a portfolio having a plurality of sub-portfolios, each sub-portfolio containing holdings corresponding to one of said sub-components, and each sub-portfolio having a corresponding initial weight with respect to said portfolio;", "software for defining a second index corresponding to performance of said portfolio;", "software for calculating performance for each of said sub-components relative to performance of said first index;", "software for calculating a correlation of each of said sub-components with said first index;", "and software for periodically rebalancing said portfolio by increasing weights of sub-portfolios corresponding to sub-components out-performing said first index and decreasing weights of sub-portfolios corresponding to sub-components under-performing said first index;", "except that for sub-components having the respective calculated correlation differing with said first index, corresponding sub-portfolios do not have weight increased.", "Other embodiments of the invention include: providing one or more exchange traded notes based on said second index, said exchange traded notes do not pay interest during the term of said notes, said first index is a total return index, said second index is a total return index, said portfolio is rebalanced daily, said first index is the S&P 500 Total Return Index, and/or each of said sub-components receives a weight increase or decrease only when said weight increase or decrease when compared to a prior weight for each of said sub-components exceeds a specified threshold value.", "BRIEF DESCRIPTION OF THE DRAWINGS [0036] FIG. 1 depicts a computer system for implementing an embodiment of the invention.", "[0037] FIG. 2 depicts a flowchart of a method according to an embodiment of the invention.", "DETAILED DESCRIPTION [0038] I. Sectors Total Return Level Calculation [0039] Summary: The purpose of this section is to describe, for an exemplary embodiment, the Sector Total Return Levels that will be representative of each Level 1 GICS Sector.", "Each Sector is associated with an S&P 500 Sub-Index.", "On each Sector Calculation Day, the Sector Total Return Levels are calculated by reinvesting the dividends paid by the relevant S&P 500 Sub-Index on this Index Calculation Day (1).", "[0040] Sector Description: Each Level 1 GICS sector is represented by an S&P 500 Sub-Index: [0000] TABLE 3 S&P 500 Sub- Index i Bloomberg I Sector i S&P 500 Sub-Index i Ticker 1 Consumer S&P 500 Consumer S5COND Index Discretionary Discretionary Index 2 Consumer Staples S&P 500 Consumer Staples S5CONS Index Index 3 Energy S&P 500 Energy Index S5ENRS Index 4 Financial S&P 500 Financials Index S5FINL Index 5 Healthcare S&P 500 Health Care Index S5HLTH Index 6 Industrial S&P 500 Industrials Index S5INDU Index 7 Materials S&P 500 Materials Index S5MATR Index 8 Telecommunication S&P 500 S5TELS Index Telecommunication Index 9 Technology S&P 500 Information S5INFT Index Technology Index 10 Utilities S&P 500 Utilities Index S5UTIL Index [0041] Sector Level On the Initial Sectors Calculation Day, the Initial Sector i Total Return Level will be determined as follows, for i=1 .", "10: [0000] Sector 0 i =100 [0042] On each Index Calculation Day, the Sector i Total Return Level will be determined as follows, for i=1 .", "10: [0000] Sector t i = Sector t - 1 i · SubIndex t i + SubIndexDiv t i SubIndex t - 1 i ( 1 ) [0043] Where: [0044] Sector i t−1 is the Sector i Total Return Level as of the Sectors Calculation Day preceding t. [0045] SubIndex i t is the S&P 500 Sub-Index i Close Level as of Sectors Calculation Day t, as published on the above relevant Bloomberg Page.", "[0046] SubIndex i t−1 is the S&P 500 Sub-Index i Close Level as of the Sectors Calculation Day preceding t, as published on the above relevant Bloomberg Page.", "[0047] SubIndexDiv i t is the S&P 500 Sub-Index i Net Dividend detached on Sectors Calculation Day t. [0048] II.", "Index Calculation Methodology [0049] Summary: The purpose of this section is to describe, for an exemplary embodiment, SPECTRUM US Index Level in reference to the various Sector Total Returns, as described in the preceding section, and the various Sector Weights, as described in the following section.", "As detailed in the section entitled “Allocation Methodology,” the SPECTRUM US Index preferably is rebalanced only on Reallocation Dates.", "Consequently, on each Index Calculation Date, the SPECTRUM US Index level will be calculated in reference to the SPECTRUM US Index Level as of the strictly preceding Reallocation Date, and the Sector Weights as determined on this Reallocation Date.", "The Performance of the SPECTRUM US Index since the strictly preceding Reallocation Date is equal to the sum of the Sector Total Return Level performances since the last Reallocation Date weighted by the Sector Weights determined on this Reallocation Date (see (2) below).", "[0050] Index Level: On the Initial Index Calculation Day, the Initial Index Level will be determined as follows: [0000] Index 0 =100 [0051] On each Index Calculation Day t, SPECTRUM US Index Level will be determined as follows: [0000] Index t = Index r · ∑ i = 1 10   ( W r i · Sector t 1 Sector r i ) ( 2 ) [0052] Where: [0053] Index r is Index Level as of the Reallocation Date strictly preceding SPECTRUM US Index Calculation Day t. [0054] The Initial Index Calculation Day is a Reallocation Date.", "[0055] W r i is Sector i Weight in SPECTRUM US Index as of the Reallocation Date strictly preceding SPECTRUM US Index Calculation Day t, as defined in the next section (“Allocation Methodology”).", "[0056] Sector t i is Sector i Total Return Level as of Index Calculation Day t, as defined in the preceding section (“Sectors Total Return Level Calculation”).", "[0057] Sector r i is Sector i Total Return Level as of the Reallocation Date strictly preceding SPECTRUM US Index Calculation Day t. [0058] III.", "Allocation Methodology [0059] Summary: The purpose of this section is to describe, for an exemplary embodiment, SPECTRUM US Index Allocation between the 10 Sectors used in an embodiment.", "[0060] How the Weights of the Sub-Indices are Calculated [0061] On any Index Calculation Day, Target Weights will be calculated for each of the Sub-Indices.", "This is the purpose of the Section Target Weight Determination.", "On any Index Calculation Day, each Sector is given a Target Weight, in accordance with the following procedure: [0062] This methodology is based on trend following.", "Using the sliding average of the close levels for each Sub-index and SPTR permits determination and comparison of the trends between these sectors and the S&P 500 Total Return.", "The Average Level is defined as the average of the Close Levels over the last 120 Sector Calculation Days.", "See (6) &", "(8) below.", "[0063] Then the trend of each sector and SPTR will be quantified by calculating the Sector and SPTR Performances.", "These Performances will represent the trend in the rest of this methodology.", "They are calculated as the Annualized Performances over the last 120 Sector Calculation Days of the Average Levels.", "See (5) &", "(7) below.", "[0064] These Performances, representing trends, will then be used in the calculation of the Sector Coefficients (4).", "The goals of this formula are: [0065] (a) To give a greater Coefficient to Sectors showing a greater Performance than the S&P 500 Total Return's Performance, and conversely (i.e., a smaller coefficient is given to Sectors showing a lesser Performance).", "Sectors out-performing SPTR will be given a Sector Coefficient greater than 1, out-performance being defined as a Performance greater than SPTR's Performance.", "Sector under-performing SPTR will be given a Sector Coefficient lower than 1, so that out-performing Sectors, in the sense of the indicators used in the methodology, will be over-weighted in SPECTRUM US Index, and conversely (under-performing Sectors are under-weighted).", "[0066] (b) To control and to limit the over-weighting of Sectors showing a poor correlation with the S&P 500 Total Return.", "Indeed, an excessive over-weighting of Sectors poorly correlated to SPTR would result in SPECTRUM US Index itself showing a poor correlation with the S&P 500 Total Return.", "As an example, Sectors anti-correlated with SPTR (i.e., showing a correlation with SPTR negative or equal to zero) will be given a Sector Coefficient of 1.", "Over or under weighting of each sub-index may be approximately proportional to a 6 month correlation of its daily returns with SPTR's daily returns so that sub-indices well correlated with SPTR will be over-weighted.", "The Sector Coefficients are not Weights.", "Indeed, their sum is likely to be different than 1.", "The Sector Target Weights are calculated by normalizing the Sector Coefficients (see (3) below), which means that the Sector Target Weights are proportional to the Sector Coefficients and that their sum is equal to 1.", "[0067] When the SPECTRUM US Index is Rebalanced [0068] The Target Weights are calculated on a daily basis.", "They factor in the latest information for implementing a momentum strategy, given the trend indicators that are used.", "However, SPECTRUM US Index preferably is not rebalanced every day.", "It is rebalanced only when the Target Allocation is deemed different enough from the Allocation which was used in the SPECTRUM US Index since the latest Reallocation Date.", "In order to quantify this difference and determine the occurrence of a Reallocation Event, the following procedure is applied on a daily basis: [0069] (i) The Target Allocation and the Allocation can be represented by two vectors, made of the 10 Sector Target Weights, for the Target Allocation, and the 10 Sector weights for the Allocation in place in SPECTRUM US Index.", "The Distance, as calculated in (10) is a positive number that quantifies how different these two vectors are, and therefore quantifies the difference between Target and Sector Weights.", "[0070] For example, if, for any given Sector, the Sector Target Weight is equal to the Sector Weight, the Distance will be equal to zero.", "For any particular Sector, the greater the difference between the Target Sector Weight and the Sector Weight, the greater the Distance.", "[0071] (ii) A Reallocation Event is deemed to occur if the Distance is strictly greater than 20%.", "[0072] (iii) Then, SPECTRUM US Index Rebalancing will take place two Index Calculation Days after the occurrence of a Reallocation Event (see (9) below).", "[0073] IV.", "Sector Target Weights Determination [0074] Target Weights: On each Index Calculation Day, the Sector i Target Weight will be determined as follows, for i=1 .", "10: [0000] Wtg t i = Coeff t i ∑ i = i 10   Coeff t i ( 3 ) [0075] Where: Coeff t i is Sector i Target Coefficient as of Index Calculation Day t. [0076] Target Coefficients: On each Index Calculation Day, the Sector i Target Coefficient will be determined as follows, for i=1 .", "10: [0000] Coeff t i = Max [ 0 , 1 + Max  ( ρ t i , 0  % ) × 150  % × Perf t i - Perf t SPTR 1 10  ∑ j = 1 10  | Perf t i - Perf t SPTR | ] ( 4 ) [0077] Where: [0078] ρ t i is Sector i Correlation as of Index Calculation Day t;", "[0079] Perf t i is Sector i Performance as of Index Calculation Day t;", "and [0080] Perf t SPTR is SPTR Performance as of Index Calculation Day t. [0081] Sector Correlation: The Sector i Correlation as of Index Calculation Day t, ρ t i , will be determined by the Calculation Agent, for i=1 .", "10, as the Correlation of the Daily Returns of Sector i with the Daily Returns of SPTR, over a period of 120 Index Calculation Days ending on Index Calculation Day t. [0082] Sector Performance: On each Index Calculation Day, the Sector i Performance will be determined as follows, for i=1 .", "10: [0000] Perf t i = ( Average t i Average t - 120 i ) 2 - 1 ( 5 ) [0083] Where: [0084] Average t i is Sector i Average Level as of Index Calculation Day t;", "and [0085] Average i t−120 is Sector i Average Level as of the Sector Calculation Day which 120 Sector Calculation Days before Index Calculation Day t. [0086] Sector Average Level: On each Sectors Calculation Day, the Sector i Average Level will be determined as follows, for i=1 .", "10: [0000] Average t i = 1 120  ∑ s = 0 119   Sector t - s i ( 6 ) [0087] Where: [0088] Sector i t−s is Sector i Total Return Level as of the Sector Calculation Day which is s Sector Calculation Days before Sector Calculation Day t. [0089] SPTR Performance: On each Index Calculation Day, the SPTR Performance will be determined as follows: [0000] Perf t SPTR = ( Average t SPTR Average t - 120 SPTR ) 2 - 1 ( 7 ) [0090] Where: [0091] Average t SPTR is SPTR Average Level as of Index Calculation Day t;", "and [0092] Average SPTR t−120 is SPTR Average Level as of the Sector Calculation Day which 120 Sector Calculation Days before Sector Calculation Day t. [0093] SPTR Average Level: On each Index Calculation Day, the SPTR Average Level will be determined as follows: [0000] Average t SPTR = 1 120  ∑ s = 0 119   SPTR t - s ( 8 ) [0094] Where: SPTR t−s is SPTR Close Level as of the Sector Calculation Day which is s Sector Calculation Days before Sector Calculation Day t. [0095] V. Sector Weights Determination [0096] Sector Weights On the Initial Index Calculation Day, the Initial Sector i Weights will be determined as follows, for i=1 .", "10: [0000] W 0 i =Wtg 0 i [0097] Where: [0098] Wtg i 0 is Sector i Target Weight as of the Initial Index Calculation Date.", "[0099] The Initial Index Calculation Day preferably is a Reallocation Date.", "[0100] On each Index Calculation Day t, following the determination of the Sector Target Weights, the Calculation Agent will determine SPECTRUM US Index Allocation between the Sectors as follows: [0101] If t+1 is a Reallocation Date, then t+2 won't be a Reallocation Date.", "[0102] If t+1 is not a Reallocation Date, and Distance t ≦20%, then t+2 won't be a Reallocation Date.", "[0000] If t+1 is not a Reallocation Date, and Distance t >20%, then a Reallocation Event is deemed to occur and t+2 will be a Reallocation Date: for i=1 .", "10, W t+2 i =Wtg t i (9) [0103] Where: [0104] t+1 is Index Calculation Day which is I Index Calculation Day after Index Calculation Day t. [0105] t+2 is Index Calculation Day which is 2 Index Calculation Days after Index Calculation Day t. [0106] Distance t is the Distance as of Index Calculation Day t. [0107] Distance: On each Index Calculation Day t, the Distance will be calculated as follows: [0000] Distance t = ∑ t = 1 10   ( W r i - Wtg t i ) 2 ( 10 ) [0108] Where: [0109] W t i is Sector i Weight as of the Reallocation Date strictly preceding SPECTRUM US Index Calculation Day t;", "and [0110] Wtg t i is Sector i Target Weight as of Index Calculation Day t. [0111] Exemplary Terms for Exchange Traded Notes [0112] Exemplary terms for Exchange Traded Notes linked to the SPECTRUM US Sector Momentum Index are provided below.", "[0113] The Exchange-Traded Notes due [], 2016 (the “Securities”) are linked to the SPECTRUM US Sector Momentum Index, do not guarantee any return of principal at maturity, and do not pay any interest during their term.", "Instead, a purchaser will receive a cash payment at maturity or early redemption based on the performance of the S&P Custom/BNP Paribas—SPECTRUM US Sector Momentum Index less an investor fee.", "The principal terms of the Securities are as follows: [0114] Issuer: [Issuer] [0115] Underlying Index The return on the Securities is linked to the performance of the SPECTRUM US Sector Momentum Index (the “Index”).", "The Index is positioned as a “U.S. equity large cap”", "investment.", "The Index is published under the symbol <Index>.", "[0116] Payment at Maturity: If a purchaser holds his or her Securities to maturity, the purchaser will receive a cash payment at maturity equal to the principal amount of the held Securities limes the index factor on the final valuation date limes the fee factor on the final valuation date.", "[0117] Secondary Market: The Securities are listed on the New York Stock Exchange under the ticker symbol “[Securities Symbol].”", "If an active secondary market in the Securities develops, we expect that investors will purchase and sell the Securities primarily in this secondary market.", "[0118] Early Redemption: Subject to the notification and minimum amount requirements described below, a purchaser may redeem his Securities on any redemption date during the term of the Securities.", "If the purchaser redeems his Securities, he will receive a cash payment in an amount equal to the weekly redemption value, which is the principal amount of his Securities times the index factor on the applicable valuation date limes the fee factor on the applicable valuation date.", "The purchaser must redeem at least 250,000 Securities (a principal amount equal 1-NY/2266897.2 to at least $2.5 million) at one time in order to exercise his right to redeem his Securities on any redemption date.", "[0119] Redemption Mechanics: In order to redeem his Securities on a redemption date, a purchaser must deliver a notice of redemption via email by no later than 11:00 a.m. New York City time on the business day prior to the applicable valuation date.", "[0120] Valuation Date: Valuation date means each [Thursday] from [], 2007 to [], 2017 inclusive or, if such date is not a trading day, the next succeeding trading day, not to exceed five business days.", "We refer to [Thursday], [], 2017, as the “final valuation date.”", "[0121] Redemption Date: A redemption date is the third business day following a valuation date (other than the final valuation date).", "The final redemption date will be the third business day following the valuation date that is immediately prior to the final valuation date.", "[0122] Inception Date: [], 2007.", "[0123] Index Factor: The index factor on any given day will be equal to the closing value of the Index on that day divided by the initial index level.", "The initial index level is the closing value of the Index on the inception date.", "[0124] Fee Factor: The fee factor is equal to one minus the investor fee.", "The investor fee is equal to 0.75% times the number of calendar days elapsed from the inception date up to and including the applicable valuation date divided by 365.", "[0125] Because the investor fee and the fee factor reduce the amount of return at maturity or upon redemption, the value of the Index must increase significantly in order for a purchaser to receive at least the principal amount of your investment at maturity or upon redemption.", "If the value of the Index decreases or does not increase sufficiently, a purchaser will receive less than the principal amount of his investment at maturity or upon redemption.", "[0126] Trading Day: A trading day is a day on which (i) the value of the Index is calculated and published, (ii) trading is generally conducted on the New York Stock Exchange, and (iii) trading is generally conducted on the markets on which the futures contracts underlying the Index are traded, in each case as determined by the calculation agent in its sole discretion.", "[0127] Valuation of the Securities [0128] The market value of the Securities will be affected by several factors.", "We expect that generally the value of the Index on any day will affect the market value of the Securities more than any other factors.", "Other factors that may influence the market value of the Securities include, but are not limited to, supply and demand for the Securities, the volatility of the Index, the levels of the Sub-indices, the market price of the Index Components, prevailing interest rates, the volatility of securities markets, economic, financial, political, regulatory, geographical, biological or judicial events that affect the value of the Index or the market price of Index Components, the general interest rate environment, as well as the perceived creditworthiness of AIG.", "Indicative Value [0129] An intraday “indicative value”", "meant to approximate the intrinsic economic value of the Securities will be calculated: [0000] Indicative Value=Principal Amount per Security×(Current Index Level/Initial Index Level)×Current Fee Factor [0130] where: Principal Amount per Security=$10;", "Current Index Level=The most recent published level of the Index as reported by the AIG-FP;", "Initial Index Level=The level of Index on the inception date;", "and Current Fee Factor=The most recent daily calculation of the fee factor with respect to your Securities, determined as described above (which, during any trading day, will be the fee factor determined on the preceding calendar day).", "[0131] The indicative value will be derived from sources deemed reliable.", "[0132] Inventions described herein may be automated and used in the exemplary system of FIG. 1 .", "As shown, client computers 200 communicate via network 210 with a central server 230 which is coupled to one or more databases 240 , one or more processors 250 , and software 260 .", "Other components and combinations of components may also be used to support processing and calculations described herein as will be evident to one of skill in the art.", "Server 230 facilitates communication of returns data from a database 240 to and from clients 200 .", "Processor 250 provides calculations relevant to calculations described herein.", "Software 260 can be installed locally at a client 200 and/or centrally supported for facilitating calculations and applications.", "For example, software 260 may be used in embodiments where a threshold, e.g., for weights is established.", "[0133] Embodiments of the invention may be provided according to the flowchart of FIG. 2 .", "As shown, a first index having sub components is identified, step 310 .", "A portfolio is constructed having sub-portfolios, step 320 .", "A second index is defined corresponding to performance of the portfolio, step 330 .", "A performance of each of the sub-components relative to performance of the first index is calculated, step 340 .", "A correlation of each of the sub components relative to the first index is calculated, step 350 .", "The portfolio is rebalanced, step 360 .", "[0134] Although certain embodiments have been described in detail herein, it will be apparent to those skilled in the relevant art that various modifications, additions, substitutions and the like can be made without departing from the scope of the invention as defined in the following claims." ]
BACKGROUND OF THE INVENTION This invention relates to wrapping machines in general and, more precisely, to the devices used to infeed pieces of wrapping material to, in particular, cigarette wrapping and packeting machines. It has as its subject a device of this type, improved to prepare pieces of lined foil for use in the formation of the inner wrap in packets of cigarettes of the hinge lid type. DESCRIPTION OF THE PRIOR ART Cigarette packets of the hinge lid type consist, as is known, of a wrapper of lined foil, placed in direct contact with the cigarettes, a parallelepiped shaped cardboard box complete with hinged lid and, finally, an overwrap executed with transparent material. With particular reference to the inner wrap of lined foil, this is wrapped around the batch of cigarettes from all sides, in such a way as to protect them while the subsequent wrapping operations are taking place. Once the packet has been opened by removal of the transparent overwrap and the lid has been tipped back, in order to render the upper extremities of the cigarettes accessible, a part of the inner lined foil wrap has to be removed. It is known for this purpose to make the inner wrap out of two separate pieces of lined foil which, when the wrap has been completed, are partly superposed one over the other. The removable part of the inner wrap can be made in such a way as to cover, in the form of a hood, the entire upper part of the batch of cigarettes, or in a way whereby it covers the front and partially the two sides and the top of the said upper part of the batch of cigarettes. These inner wrap portions are, conventionally, often made in the form known as "bag type wrap". Such a wrap comprises a U-folded bottom portion, longitudinal flaps folded over one another on both sides of the batch of cigarettes and a top portion closed by folding over one another the lateral flaps. The known use of two separate pieces of lined foil for an inner wrap, and particularly for a bag type wrap, has the disadvantage that the final operations for the wrapping of the upper part of the batch of cigarettes in a second piece of wrapping material complicate matters considerably. Aside from this problem, there is a need in this case for a separate infeed and wrapping apparatus for the wrapping sheet forming the hood, independent of the infeed and wrapping apparatus for the other wrapping sheet. With a view to overcoming these difficulities but always bearing in mind the need for the upper part of the wrap to be either totally or partially removed, an inner wrap generally shaped according to the known art is also made of one single piece of lined foil on which one or two weakening lines, transverse and crosswise with respect to the direction in which the web moves and running across its full width, have previously been made. These transverse weakening lines, consisting of a series of perforations which can be in various shapes and slanting at various angles, are positioned in such a way as to allow, when the wrap is finished, the removal of the front part of the "hood" of the inner wrap (see FIG. 2) or the total removal of the "hood" (FIG. 9). The conventional techniques described up to here have been completely abandoned by the Applicant's Assignees for their soft packet cigarette packing machine according to U.S. Pat. No. 3,628,309, a very high output speed machine, whereon batches of cigarettes move forward in a crosswise direction transverse with respect to their axes, the purpose of which is to prevent any axial stress from occurring. The transversely moving batch meets a sheet of material which according to the patent, is infed in a direction perpendicular to that in which the batch travels. This sheet is then dragged towards the folding station by the batch of cigarettes. Fixed and movable folding fingers then attend to the forming of the inner wrap which instead of being wound around the cigarettes themselves, is wound around mechanical members which are gradually inserted between the folding fingers and the cigarettes, to guarantee not only the cigarettes being protected but also wraps being perfectly made in the "soap" style, which will be defined hereinafter. The excellent results obtained with the machine according to the patent, in the field of packing cigarettes in the soft cup type of packet, make it desirable to use the same technical principles and the same "soap" style of wrap for forming the inner lined foil wrap around batches of cigarettes destined to be packed in packets of the hinge lid types. This leads to the problem that, to enable the top part of the inner wrap to be easily removed, either totally or in part, at the time the packet is coming into use, a series of perforations need to be made in the wrapping sheet, transversely of the cigarettes. The problem is connected with the fact that according to the patent, the arrangement of the batch of cigarettes is not the same as that of the infeed line for the wrapping material. SUMMARY OF THE INVENTION In order to wrap the cigarettes, on a machine generally according to the patent and the "soap" style, it is necessary that at least the principal weakening lines be made longitudinally in the direction in which the lined foil is infed. This direction is shown by vertical arrows in FIGS. 3, 4 and 6. When it is wished that, on opening the hinge lid HL of the package CP, the entire upper part of the inner wrap is to be detached (see FIGS. 6, 9), the weakening line L' must stretch the full length of the cutting or sheet S. If only the front part of the inner wrap is to be detached (see FIGS. 2, 4), the weakening line L need only run along a part of the length of the sheet S, that is to say, along the section which, when the wrap has been completed, is positioned across the front and part of the sides of the batch of cigarettes. In this second case, the delimitation of the part to be removed from the sheet is completed by a series of crosswise perforations which extend from the lower extremity of the longitudinal line L to the edge of the sheet. The present invention, therefore, modifies the device described in the cited Patent, formerly used only for infeeding wrapping sheet material for forming the lined foil inner wrap for soft packets of cigarettes. The modified device is to be used for the preparation of an inner wrap, a part of which is detachable, for each packet of cigarettes of the hinge lid type. The new inner wraps are produced in which is known as the "soap" style (as known from the cited patent, and described hereinafter). A preferred embodiment of the improved device comprises, from top to bottom, means for guiding a single, continuous web of wrapping material to provide inner wrappers of cigarette batches, longitudinally of the length of the web and transversely of the cigarettes to be wrapped in sheets but from the web, these means consisting of a pair of counter rotating rollers; and cutting means, counter rotating at different angular velocities, to separate transversely to the direction of movement of the web, the web into individual pieces; and working in conjunction with the drive rollers, means for scoring a weakening line longitudinally in the direction in which the web moves forward, in order to delimitate at least a part detachable from each piece of wrapping materials, also comprising backup means for the scoring means. BRIEF DESCRIPTION OF THE DRAWINGS In the Drawings: FIG. 1 shows a perspective view of a cigarette packet of the hinge lid type in which can be made with the aid of the device according to the invention; FIG. 2 shows an exploded perspective view of the same packet at the time the inner wrap is opened; FIG. 3 shows, in a perspective view, the complete device forming the subject of the present invention together with its operating means. FIG. 4 is a perspective view, of material produced by the device of FIG. 3; FIG. 5 is a detail from FIG. 3; FIG. 6 is a modification of FIG. 4; and FIG. 7 is a modified detail from FIG. 3; and FIGS. 8 and 9 show views corresponding to those of FIGS. 1 and 2, respectively, for a modified hinge lid packet. DESCRIPTION OF THE PREFERRED EMBODIMENT With particular reference to FIGS. 3 to 7, at N, there is a continuous web of lined foil, guided by means not depicted in the figure to a narrow vertical guide channel defined by two vertical and parallel guide walls 1 and 2. A horizontal shaft 3 drives the complete device and this, integral at one end with a gearwheel 4, rotates clockwise. A gear 5 takes its movement from the aforementioned gearwheel 4 and, in turn, causes a gear 6 to rotate. Gears 5 and 6 are keyed on to the horizontal shafts 7 and 8, respectively, which are placed at the same level, on both sides of and parallel to the vertical plane for the infeeding of the web of lined foil N. Shafts 7 and 8 have keyed on to them rollers 9 and 10, respectively, which counter rotate in close contact with each other in such a way as to move the web N longitudinally as indicated by the arrow. On the shaft 8, at a point corresponding to where there is a break in the roller 10, either a disk 11 (see FIG. 5) or, alternatively, a disk 12 (see FIG. 7) is keyed on. Along their edge, both disks 11 and 12 are provided with a number of cutting areas Z which, in the case of the former extend for 180° and in the case of the latter, extend for 360°, these being designed to produce on the web N, as it moves forward between the rollers 9 and 10, a succession of vertical perforations LA, LB etc. To be more precise, when the disk 11 is used, the vertical weakening line L seen on the finished cutting depicted in FIG. 4 is created, which according to the invention, extends parallel to the side edges E of the web N (transversely of the cigarettes C to be wrapped in sheet S cut from web N), from the top edge T of sheet S to a portion P central between top edge T and the bottom edge B of the sheet. The use of the disk 12, instead, makes it possible to trace the weakening line L', which extends parallel to the side edges E of the web N (transversely of the cigarettes C to be wrapped in sheet S cut from web N), from the top edge T of sheet S to a portion P central between top edge T and the bottom edge B of the sheet. The use of the disk 12, instead, makes it possible to trace the weakening line L', which extends parallel to edges E from one end T of the sheet or cutting to the other end B, as shown in FIG. 6. During its cutting operation, the disk 11 (or 12) is restrained or backed up by a roller 13 loosely mounted on shaft 7 between parts 9A, 9B of the roller 9, on a bush 14 able to effect small oscillations with respect to the shaft 7 passing in the inside thereof. The roller 13 and the bush 14 are, in fact, supported by a vertical two armed lever 15 pivoted on to a horizontal pin 16 parallel with the shafts 7 and 8 and integral with the guide wall 1. Perpendicularly to the infeed plane of the web N, a hollow screw 17 is mounted on the end of the second arm of lever 15, inside which a spring 18 is placed and this presses against the guide wall 1. The extent to which the back-up roller 13 applies a restraining action to the cutting edge of the disk 11 (or 12) can be set by means of the hollow screw 17. An adjusting screw 19 is fitted perpendicularly to the infeed plane of the web N to the first arm of the lever 15 and extends toward the guide wall 1. When roller 13 encounters the broken area O between the ends of the cutting edge Z of the disk 11 extending for 180°, screw 19 prevents the roller 13 from exerting a pressing, deforming action on the web N. Besides carrying in rotation the aforementioned gear 5, the gearwheel 4 also drives a gear 20 keyed on to a shaft 21. Shaft 21 also has keyed on to it a gear 22 which, in turn, carries in rotation a gear 23 rigidly mounted on a shaft 24. The shafts 21 and 24 are parallel with the shafts 7 and 8 and they counter rotate at different angular velocities since the ratio between the number of teeth in the gears 22 and 23 is equal to 2. Furthermore, to the shafts 21 and 24, parallel with their axes, are fixed the rectangular plates 25 and 26, respectively, and these are provided with cutting edges which, coming into reciprocal contact along the infeed plane, detach individual pieces of lined foil, perforated by the disk 11 (or 12), from the continuous web N. It should be noted that, for the reasons outlined, one piece or sheet S is cut off each time the gear 22 completes a full rotation and each time the gear 23 completes two full rotations. When the disk 11 is used to trace the vertical perforations, the weakening line L delimitating the part of the inner wrap that can be removed at the time the packet is opened, has to be completed, as already stated, by a line L" consisting of a number of perforations made transversely with respect to the direction in which the web N moves forward. This operation is performed by a plate 27 fixed, in a diametrically opposed position to the plate 25, on the shaft 21 and provided along its edge with a plurality of cutting edges Z'. The plate 27 also operates in conjunction with the cutting edge of the plate 26, alternating with the operation of cutting the individual pieces. When looking at FIGS. 2 and 9, it can be seen that to detach the removable part T or T' of the inner wrap, tractive force has to be applied to this part. So as to render this operation easier, it is advisable that the areas connecting the removable part T or T' with the remainder of the inner wrap be positioned in such a way that a bending moment stress be applied thereto at the time of opening. This is the reason why the cutting edges Z, Z' of the disks 11 and 12 and of the plate 27 only have breaks ZO, ZO' in them, located so as to provide breaks LO, LO' in the weakening lines L, L" at points corresponding to where the pre-folding lines LP (shown in dashes in FIGS. 4 and 6) are located, that is to say, the lines which constitute the corners and edges of the inner wrap once the wrap has been completed, in the "soap" style of wrapping produced according to U.S. Pat. No. 3,628,309. This style of wrapping produces an inner wrap CP (FIG. 1) from sheet S (FIG. 6), wherein longitudinal flaps of the sheet are produced and folded over one another on a single side of the batch of cigarettes, and the top and bottom ends of the packet are closed by folding over one another the lateral flaps EL along the edges E, overlying the ends CE of the cigarettes (FIGS. 1, 8). Heretofore, as already mentioned, this style of wrap was available only for soft type cigarette packets. By the present invention, this style of wrap becomes available also for hard type, hinge-lid cigarette packets.
A device for preparing pieces of wrapping material for use as inner wraps in hinge-lid cigarette packets. The device comprises a pair of rollers, rotating in opposite directions, which move a web of wrapping material downwards; a scoring disk rotating with one of the rollers to trace a sheet-weakening line of the web, longitudinally in the direction in which the web moves in such a way as to delimitate a part that can be subsequently detached from the web; and cutting rolls which transversely cut the web into individual sheets.
Briefly summarize the invention's components and working principles as described in the document.
[ "BACKGROUND OF THE INVENTION This invention relates to wrapping machines in general and, more precisely, to the devices used to infeed pieces of wrapping material to, in particular, cigarette wrapping and packeting machines.", "It has as its subject a device of this type, improved to prepare pieces of lined foil for use in the formation of the inner wrap in packets of cigarettes of the hinge lid type.", "DESCRIPTION OF THE PRIOR ART Cigarette packets of the hinge lid type consist, as is known, of a wrapper of lined foil, placed in direct contact with the cigarettes, a parallelepiped shaped cardboard box complete with hinged lid and, finally, an overwrap executed with transparent material.", "With particular reference to the inner wrap of lined foil, this is wrapped around the batch of cigarettes from all sides, in such a way as to protect them while the subsequent wrapping operations are taking place.", "Once the packet has been opened by removal of the transparent overwrap and the lid has been tipped back, in order to render the upper extremities of the cigarettes accessible, a part of the inner lined foil wrap has to be removed.", "It is known for this purpose to make the inner wrap out of two separate pieces of lined foil which, when the wrap has been completed, are partly superposed one over the other.", "The removable part of the inner wrap can be made in such a way as to cover, in the form of a hood, the entire upper part of the batch of cigarettes, or in a way whereby it covers the front and partially the two sides and the top of the said upper part of the batch of cigarettes.", "These inner wrap portions are, conventionally, often made in the form known as "bag type wrap".", "Such a wrap comprises a U-folded bottom portion, longitudinal flaps folded over one another on both sides of the batch of cigarettes and a top portion closed by folding over one another the lateral flaps.", "The known use of two separate pieces of lined foil for an inner wrap, and particularly for a bag type wrap, has the disadvantage that the final operations for the wrapping of the upper part of the batch of cigarettes in a second piece of wrapping material complicate matters considerably.", "Aside from this problem, there is a need in this case for a separate infeed and wrapping apparatus for the wrapping sheet forming the hood, independent of the infeed and wrapping apparatus for the other wrapping sheet.", "With a view to overcoming these difficulities but always bearing in mind the need for the upper part of the wrap to be either totally or partially removed, an inner wrap generally shaped according to the known art is also made of one single piece of lined foil on which one or two weakening lines, transverse and crosswise with respect to the direction in which the web moves and running across its full width, have previously been made.", "These transverse weakening lines, consisting of a series of perforations which can be in various shapes and slanting at various angles, are positioned in such a way as to allow, when the wrap is finished, the removal of the front part of the "hood"", "of the inner wrap (see FIG. 2) or the total removal of the "hood"", "(FIG.", "9).", "The conventional techniques described up to here have been completely abandoned by the Applicant's Assignees for their soft packet cigarette packing machine according to U.S. Pat. No. 3,628,309, a very high output speed machine, whereon batches of cigarettes move forward in a crosswise direction transverse with respect to their axes, the purpose of which is to prevent any axial stress from occurring.", "The transversely moving batch meets a sheet of material which according to the patent, is infed in a direction perpendicular to that in which the batch travels.", "This sheet is then dragged towards the folding station by the batch of cigarettes.", "Fixed and movable folding fingers then attend to the forming of the inner wrap which instead of being wound around the cigarettes themselves, is wound around mechanical members which are gradually inserted between the folding fingers and the cigarettes, to guarantee not only the cigarettes being protected but also wraps being perfectly made in the "soap"", "style, which will be defined hereinafter.", "The excellent results obtained with the machine according to the patent, in the field of packing cigarettes in the soft cup type of packet, make it desirable to use the same technical principles and the same "soap"", "style of wrap for forming the inner lined foil wrap around batches of cigarettes destined to be packed in packets of the hinge lid types.", "This leads to the problem that, to enable the top part of the inner wrap to be easily removed, either totally or in part, at the time the packet is coming into use, a series of perforations need to be made in the wrapping sheet, transversely of the cigarettes.", "The problem is connected with the fact that according to the patent, the arrangement of the batch of cigarettes is not the same as that of the infeed line for the wrapping material.", "SUMMARY OF THE INVENTION In order to wrap the cigarettes, on a machine generally according to the patent and the "soap"", "style, it is necessary that at least the principal weakening lines be made longitudinally in the direction in which the lined foil is infed.", "This direction is shown by vertical arrows in FIGS. 3, 4 and 6.", "When it is wished that, on opening the hinge lid HL of the package CP, the entire upper part of the inner wrap is to be detached (see FIGS. 6, 9), the weakening line L'", "must stretch the full length of the cutting or sheet S. If only the front part of the inner wrap is to be detached (see FIGS. 2, 4), the weakening line L need only run along a part of the length of the sheet S, that is to say, along the section which, when the wrap has been completed, is positioned across the front and part of the sides of the batch of cigarettes.", "In this second case, the delimitation of the part to be removed from the sheet is completed by a series of crosswise perforations which extend from the lower extremity of the longitudinal line L to the edge of the sheet.", "The present invention, therefore, modifies the device described in the cited Patent, formerly used only for infeeding wrapping sheet material for forming the lined foil inner wrap for soft packets of cigarettes.", "The modified device is to be used for the preparation of an inner wrap, a part of which is detachable, for each packet of cigarettes of the hinge lid type.", "The new inner wraps are produced in which is known as the "soap"", "style (as known from the cited patent, and described hereinafter).", "A preferred embodiment of the improved device comprises, from top to bottom, means for guiding a single, continuous web of wrapping material to provide inner wrappers of cigarette batches, longitudinally of the length of the web and transversely of the cigarettes to be wrapped in sheets but from the web, these means consisting of a pair of counter rotating rollers;", "and cutting means, counter rotating at different angular velocities, to separate transversely to the direction of movement of the web, the web into individual pieces;", "and working in conjunction with the drive rollers, means for scoring a weakening line longitudinally in the direction in which the web moves forward, in order to delimitate at least a part detachable from each piece of wrapping materials, also comprising backup means for the scoring means.", "BRIEF DESCRIPTION OF THE DRAWINGS In the Drawings: FIG. 1 shows a perspective view of a cigarette packet of the hinge lid type in which can be made with the aid of the device according to the invention;", "FIG. 2 shows an exploded perspective view of the same packet at the time the inner wrap is opened;", "FIG. 3 shows, in a perspective view, the complete device forming the subject of the present invention together with its operating means.", "FIG. 4 is a perspective view, of material produced by the device of FIG. 3;", "FIG. 5 is a detail from FIG. 3;", "FIG. 6 is a modification of FIG. 4;", "and FIG. 7 is a modified detail from FIG. 3;", "and FIGS. 8 and 9 show views corresponding to those of FIGS. 1 and 2, respectively, for a modified hinge lid packet.", "DESCRIPTION OF THE PREFERRED EMBODIMENT With particular reference to FIGS. 3 to 7, at N, there is a continuous web of lined foil, guided by means not depicted in the figure to a narrow vertical guide channel defined by two vertical and parallel guide walls 1 and 2.", "A horizontal shaft 3 drives the complete device and this, integral at one end with a gearwheel 4, rotates clockwise.", "A gear 5 takes its movement from the aforementioned gearwheel 4 and, in turn, causes a gear 6 to rotate.", "Gears 5 and 6 are keyed on to the horizontal shafts 7 and 8, respectively, which are placed at the same level, on both sides of and parallel to the vertical plane for the infeeding of the web of lined foil N. Shafts 7 and 8 have keyed on to them rollers 9 and 10, respectively, which counter rotate in close contact with each other in such a way as to move the web N longitudinally as indicated by the arrow.", "On the shaft 8, at a point corresponding to where there is a break in the roller 10, either a disk 11 (see FIG. 5) or, alternatively, a disk 12 (see FIG. 7) is keyed on.", "Along their edge, both disks 11 and 12 are provided with a number of cutting areas Z which, in the case of the former extend for 180° and in the case of the latter, extend for 360°, these being designed to produce on the web N, as it moves forward between the rollers 9 and 10, a succession of vertical perforations LA, LB etc.", "To be more precise, when the disk 11 is used, the vertical weakening line L seen on the finished cutting depicted in FIG. 4 is created, which according to the invention, extends parallel to the side edges E of the web N (transversely of the cigarettes C to be wrapped in sheet S cut from web N), from the top edge T of sheet S to a portion P central between top edge T and the bottom edge B of the sheet.", "The use of the disk 12, instead, makes it possible to trace the weakening line L', which extends parallel to the side edges E of the web N (transversely of the cigarettes C to be wrapped in sheet S cut from web N), from the top edge T of sheet S to a portion P central between top edge T and the bottom edge B of the sheet.", "The use of the disk 12, instead, makes it possible to trace the weakening line L', which extends parallel to edges E from one end T of the sheet or cutting to the other end B, as shown in FIG. 6. During its cutting operation, the disk 11 (or 12) is restrained or backed up by a roller 13 loosely mounted on shaft 7 between parts 9A, 9B of the roller 9, on a bush 14 able to effect small oscillations with respect to the shaft 7 passing in the inside thereof.", "The roller 13 and the bush 14 are, in fact, supported by a vertical two armed lever 15 pivoted on to a horizontal pin 16 parallel with the shafts 7 and 8 and integral with the guide wall 1.", "Perpendicularly to the infeed plane of the web N, a hollow screw 17 is mounted on the end of the second arm of lever 15, inside which a spring 18 is placed and this presses against the guide wall 1.", "The extent to which the back-up roller 13 applies a restraining action to the cutting edge of the disk 11 (or 12) can be set by means of the hollow screw 17.", "An adjusting screw 19 is fitted perpendicularly to the infeed plane of the web N to the first arm of the lever 15 and extends toward the guide wall 1.", "When roller 13 encounters the broken area O between the ends of the cutting edge Z of the disk 11 extending for 180°, screw 19 prevents the roller 13 from exerting a pressing, deforming action on the web N. Besides carrying in rotation the aforementioned gear 5, the gearwheel 4 also drives a gear 20 keyed on to a shaft 21.", "Shaft 21 also has keyed on to it a gear 22 which, in turn, carries in rotation a gear 23 rigidly mounted on a shaft 24.", "The shafts 21 and 24 are parallel with the shafts 7 and 8 and they counter rotate at different angular velocities since the ratio between the number of teeth in the gears 22 and 23 is equal to 2.", "Furthermore, to the shafts 21 and 24, parallel with their axes, are fixed the rectangular plates 25 and 26, respectively, and these are provided with cutting edges which, coming into reciprocal contact along the infeed plane, detach individual pieces of lined foil, perforated by the disk 11 (or 12), from the continuous web N. It should be noted that, for the reasons outlined, one piece or sheet S is cut off each time the gear 22 completes a full rotation and each time the gear 23 completes two full rotations.", "When the disk 11 is used to trace the vertical perforations, the weakening line L delimitating the part of the inner wrap that can be removed at the time the packet is opened, has to be completed, as already stated, by a line L"", "consisting of a number of perforations made transversely with respect to the direction in which the web N moves forward.", "This operation is performed by a plate 27 fixed, in a diametrically opposed position to the plate 25, on the shaft 21 and provided along its edge with a plurality of cutting edges Z'.", "The plate 27 also operates in conjunction with the cutting edge of the plate 26, alternating with the operation of cutting the individual pieces.", "When looking at FIGS. 2 and 9, it can be seen that to detach the removable part T or T'", "of the inner wrap, tractive force has to be applied to this part.", "So as to render this operation easier, it is advisable that the areas connecting the removable part T or T'", "with the remainder of the inner wrap be positioned in such a way that a bending moment stress be applied thereto at the time of opening.", "This is the reason why the cutting edges Z, Z'", "of the disks 11 and 12 and of the plate 27 only have breaks ZO, ZO'", "in them, located so as to provide breaks LO, LO'", "in the weakening lines L, L"", "at points corresponding to where the pre-folding lines LP (shown in dashes in FIGS. 4 and 6) are located, that is to say, the lines which constitute the corners and edges of the inner wrap once the wrap has been completed, in the "soap"", "style of wrapping produced according to U.S. Pat. No. 3,628,309.", "This style of wrapping produces an inner wrap CP (FIG.", "1) from sheet S (FIG.", "6), wherein longitudinal flaps of the sheet are produced and folded over one another on a single side of the batch of cigarettes, and the top and bottom ends of the packet are closed by folding over one another the lateral flaps EL along the edges E, overlying the ends CE of the cigarettes (FIGS.", "1, 8).", "Heretofore, as already mentioned, this style of wrap was available only for soft type cigarette packets.", "By the present invention, this style of wrap becomes available also for hard type, hinge-lid cigarette packets." ]
BACKGROUND [0001] The present invention relates generally to integrated circuit (IC) design, and, more particularly, to power supply management for IC memory devices. [0002] A need for low power electronics has been driven by portable applications, packing density of ICs and conservation of energy. Reducing power supply voltage is an effective way to reduce power consumption of an IC. On the other hand, ever scaling down in semiconductor device sizes demands low supply voltage operations. But small device sizes and low supply voltage cause high leakage and instability in device operations. Cell operation of a static random access memory (SRAM) is one example. FIG. 1 shows a column 100 of SRAM cells 102 [ 0 :n], where n is an integer. The SRAM cell 102 [ 0 ] shown in FIG. 1 has six transistors. Two P-type metal-oxide-semiconductor (PMOS) transistors 110 and 120 , and two N-type metal-oxide-semiconductor (NMOS) transistor 115 and 125 form two cross-coupled inverters to store a state in either node C or node D. Two NMOS transistor 130 and 135 serve as pass-gates between a pair of complementary bit-lines (BLs) 140 and 145 , and node C and D, respectively. The gates of both the NMOS transistors 130 and 135 are coupled to a word-line (WL) 150 . A high voltage power supply (Vcc) line 160 is coupled to the sources of the PMOS transistors 110 and 120 of every cell 102 in the column 100 , while a low voltage power supply (Vss) line 170 is coupled to the sources of the NMOS transistors 115 and 125 of the cells 102 [ 0 :n]. When writing to the cell 102 [ 0 ], the complementary BLs 140 and 145 are forced a voltage to overwrite a previous state stored in nodes C or D, therefore, lower Vcc will make the writing easier. When reading from the cell 102 [ 0 ], the BLs 140 and 145 become driven by nodes C and D, apparently, higher Vcc will make the reading easier. Writing and reading put contradictory demands on the Vcc. As the Vcc scales down with the device sizes, and process variations increase in proportion to the device sizes, it is increasingly difficult for a fixed power supply voltage to meet these contradictory demands. [0003] As such, what is needed is a dynamic power supply that can increase or decrease it voltage on demands. SUMMARY [0004] This invention discloses a power supply management circuit. According the one embodiment of the present invention, the power supply management circuit comprises at least one switching circuit coupled between a power supply and a power recipient circuit, and at least one voltage booster circuit coupled between a control circuit and the power recipient circuit, wherein the control circuit is configured to turn on-or-off the switching circuit, and to activate or de-activate the voltage booster circuit. [0005] According to another embodiment of the present invention, the power supply management circuit comprises at least one PMOS transistor with a source, a drain, a gate and a bulk coupled to a power supply, a power recipient circuit, a control circuit and the power recipient circuit, respectively, wherein the control circuit is configured to turn on-or-off the power supply to the power recipient circuit through switching the PMOS transistor. [0006] The construction and method of operation of the invention, however, together with additional objectives and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0007] The drawings accompanying and forming part of this specification are included to depict certain aspects of the invention. A clearer conception of the invention, and of the components and operation of systems provided with the invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings, wherein like reference numbers (if they occur in more than one view) designate the same elements. The invention may be better understood by reference to one or more of these drawings in combination with the description presented herein. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale. [0008] FIG. 1 is a schematic diagram illustrating a column of conventional 6 -T SRAM cells. [0009] FIGS. 2A˜2C are schematic diagrams illustrating three dynamic power supplies according to embodiments of the present invention. DESCRIPTION [0010] The present invention discloses various dynamic power supplies for semiconductor devices. [0011] FIG. 1 has already been described and discussed as the relevant background to the present invention. It requires no further discussion here. [0012] FIGS. 2A˜2C are schematic diagrams illustrating three dynamic power supplies according to embodiments of the present invention. Memory cells 102 [ 0 :n] illustrated here are 6-T SRAM cells shown in FIG. 1 . Between a system high voltage power supply (Vdd) and a cells' high voltage power supply Vcc line 106 , a block 202 is coupled. [0013] Referring to FIG. 2A , in a first embodiment of the present invention, the block 202 may be implemented as a PMOS transistor 212 and a capacitor 214 . A drain, a source, a gate and a bulk of the PMOS transistor 212 are coupled to the Vdd, the Vcc line 160 , the block 204 at a node 216 and the Vdd, respectively. The capacitor 214 is coupled between the Vcc line 160 and the block 204 at node 218 . During non-access or standby periods, node 216 is in a logic LOW state, and the PMOS transistor 212 is on, so that the Vcc is approximately equal to the Vdd. During writing the SRAM cell 102 periods, node 216 is temporarily turned to a HIGH logic state, which then shut off the PMOS transistor 212 , so that the Vcc line 160 becomes floating during the short writing period. Charges previously stored in the Vcc line 160 embark on a discharging process, therefore, the voltages at the floating Vcc line 160 will begin to drop, which is a favorable condition for writing. Additionally, prior to the writing period, node 218 is kept at the Vdd, hence no charge is stored in the capacitor 214 . Once entering the writing period, node 218 is temporarily turned to a voltage lower than the Vdd, such as Vss, which will force the voltage at the Vcc line 160 to drop even faster than a case where only the PMOS transistor 212 alone is employed. [0014] During reading the SRAM cell 102 periods, node 216 remains at the logic LOW state, which turns on the PMOS transistor 212 , therefore, the Vdd supplies the Vcc line 160 . But prior to the actual reading, node 218 is kept at a voltage lower than the Vdd, so that the capacitor 214 is charged. Upon a start of the reading, node 218 is switched from the low voltage to the Vdd, so that the capacitor 214 provides a voltage boost to the Vcc line 160 . As discussed earlier, higher Vcc voltage is favorable to reading the SRAM cell 120 . [0015] Referring to FIG. 2B , in a second embodiment of the present invention, the block 202 may be implemented as just a PMOS transistor 222 with a source, a drain, a gate and a bulk coupled to the Vdd, the Vcc line 160 , to a block 204 at node 226 and the Vcc line 160 , respectively. Similar to the first embodiment, the PMOS transistor 222 is turned on during reading the SRAM cell 102 , and turned off during writing the SRAM cell 102 by the block 204 . When the PMOS transistor 222 is on, the Vcc line 160 is driven by the Vdd, which is a favorable condition for reading. When the PMOS transistor 222 is off, the Vcc line 160 is floating, which is a favorable condition for writing. Beside the second embodiment does not employ a boost capacitor 214 as shown in FIG. 2A , the second embodiment differs from the first embodiment in that the bulk of the PMOS transistor 222 is coupled to the Vcc line 160 , or the drain of itself. As a result, when the PMOS transistor 222 is on, there is a voltage drop across its source and drain. The magnitude of the voltage drop equals approximately its threshold voltage. This lowered Vcc voltage condition is desirable for lowering standby leakage of the SRAM cells 102 . [0016] Referring to FIG. 2C , in a third embodiment of the present invention, the block 202 may be implemented as a PMOS transistor 232 and a capacitor 234 . A source, a drain, a gate and a bulk of the PMOS transistor 232 are coupled to the Vdd, the Vcc line 160 , to a block 204 at node 236 and the Vcc line 160 , respectively. Apparently, the connection of the PMOS transistor 232 is the same as the PMOS transistor 222 in the second embodiment. According the third embodiment, the PMOS transistor 232 also functions the same as the PMOS transistor 222 , i.e., the PMOS transistor 232 is turned on during reading the SRAM cell 102 , and turned off during writing the SRAM cell 102 by the block 204 . When the PMOS transistor 232 is on, the Vcc line 160 is driven by the Vdd, which is a favorable condition for reading. When the PMOS transistor 232 is off, the Vcc line 160 is floating, which is a favorable condition for writing. Since the bulk of the PMOS transistor 232 is coupled to the Vcc line 160 , or the drain of itself. As a result, when the PMOS transistor 232 is on, there is a voltage drop across its source and drain. The magnitude of the voltage drop equals approximately its threshold voltage. This lowered Vcc voltage condition is desirable for lowering standby leakage of the SRAM cells 102 . [0017] Then there is the boost capacitor 234 , which is connected the same as the capacitor 214 in the first embodiment. According to the third embodiment, the capacitor 234 also functions the same as the capacitor 214 , i.e., during writing the capacitor 234 helps pulling down the voltage at the floated Vcc line 160 , and during reading, the charge previously stored in the capacitor 234 provides a boost to the voltage at the Vcc line 160 , which is driven by the Vdd in reading case. [0018] Referring the FIGS. 2A˜2C , the blocks 204 are not provided with any detailed implementations, as one skilled in the art would have no difficulty to construct circuits to provide signals at the corresponding nodes 216 , 218 , 226 , 236 and 238 for these blocks. The functions of these signals are described in above paragraphs. Typically the blocks 204 may contain inverters, NOR and NAND gates, etc. [0019] The capacitor, 214 or 234 , may be formed by any appropriately available semiconductor materials in a die for a given process, such as metal-intermetal dielectric-metal (MiM), metal-oxide-semiconductor (MOS) or polysilicon-interpoly dielectric-polysilicon (PiP). [0020] With this PMOS transistor switching and capacitor voltage boosting capacities, the power supply to the SRAM cells may be dynamically managed to mean the contradictory demands of the reading and writing operations. [0021] Although the embodiments show only the SRAM cell as a recipient of the dynamic power supplies, and only the Vdd is switched according to the present invention, one having skill in the art would appreciate that the present invention may be applied to other memories or even logic circuits where contradictory voltage conditions are desired in different operations, and the Vss power supply can be similarly switched. [0022] The above illustration provides many different embodiments or embodiments for implementing different features of the invention. Specific embodiments of components and processes are described to help clarify the invention. These are, of course, merely embodiments and are not intended to limit the invention from that described in the claims. [0023] Although the invention is illustrated and described herein as embodied in one or more specific examples, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention, as set forth in the following claims.
This invention discloses a power supply management circuit which comprises at least one switching circuit coupled between a power supply and a power recipient circuit, and at least one voltage booster circuit coupled between a control circuit and the power recipient circuit, wherein the control circuit is configured to turn on-or-off the switching circuit, and to activate or de-activate the voltage booster circuit.
Briefly outline the background technology and the problem the invention aims to solve.
[ "BACKGROUND [0001] The present invention relates generally to integrated circuit (IC) design, and, more particularly, to power supply management for IC memory devices.", "[0002] A need for low power electronics has been driven by portable applications, packing density of ICs and conservation of energy.", "Reducing power supply voltage is an effective way to reduce power consumption of an IC.", "On the other hand, ever scaling down in semiconductor device sizes demands low supply voltage operations.", "But small device sizes and low supply voltage cause high leakage and instability in device operations.", "Cell operation of a static random access memory (SRAM) is one example.", "FIG. 1 shows a column 100 of SRAM cells 102 [ 0 :n], where n is an integer.", "The SRAM cell 102 [ 0 ] shown in FIG. 1 has six transistors.", "Two P-type metal-oxide-semiconductor (PMOS) transistors 110 and 120 , and two N-type metal-oxide-semiconductor (NMOS) transistor 115 and 125 form two cross-coupled inverters to store a state in either node C or node D. Two NMOS transistor 130 and 135 serve as pass-gates between a pair of complementary bit-lines (BLs) 140 and 145 , and node C and D, respectively.", "The gates of both the NMOS transistors 130 and 135 are coupled to a word-line (WL) 150 .", "A high voltage power supply (Vcc) line 160 is coupled to the sources of the PMOS transistors 110 and 120 of every cell 102 in the column 100 , while a low voltage power supply (Vss) line 170 is coupled to the sources of the NMOS transistors 115 and 125 of the cells 102 [ 0 :n].", "When writing to the cell 102 [ 0 ], the complementary BLs 140 and 145 are forced a voltage to overwrite a previous state stored in nodes C or D, therefore, lower Vcc will make the writing easier.", "When reading from the cell 102 [ 0 ], the BLs 140 and 145 become driven by nodes C and D, apparently, higher Vcc will make the reading easier.", "Writing and reading put contradictory demands on the Vcc.", "As the Vcc scales down with the device sizes, and process variations increase in proportion to the device sizes, it is increasingly difficult for a fixed power supply voltage to meet these contradictory demands.", "[0003] As such, what is needed is a dynamic power supply that can increase or decrease it voltage on demands.", "SUMMARY [0004] This invention discloses a power supply management circuit.", "According the one embodiment of the present invention, the power supply management circuit comprises at least one switching circuit coupled between a power supply and a power recipient circuit, and at least one voltage booster circuit coupled between a control circuit and the power recipient circuit, wherein the control circuit is configured to turn on-or-off the switching circuit, and to activate or de-activate the voltage booster circuit.", "[0005] According to another embodiment of the present invention, the power supply management circuit comprises at least one PMOS transistor with a source, a drain, a gate and a bulk coupled to a power supply, a power recipient circuit, a control circuit and the power recipient circuit, respectively, wherein the control circuit is configured to turn on-or-off the power supply to the power recipient circuit through switching the PMOS transistor.", "[0006] The construction and method of operation of the invention, however, together with additional objectives and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS [0007] The drawings accompanying and forming part of this specification are included to depict certain aspects of the invention.", "A clearer conception of the invention, and of the components and operation of systems provided with the invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings, wherein like reference numbers (if they occur in more than one view) designate the same elements.", "The invention may be better understood by reference to one or more of these drawings in combination with the description presented herein.", "It should be noted that the features illustrated in the drawings are not necessarily drawn to scale.", "[0008] FIG. 1 is a schematic diagram illustrating a column of conventional 6 -T SRAM cells.", "[0009] FIGS. 2A˜2C are schematic diagrams illustrating three dynamic power supplies according to embodiments of the present invention.", "DESCRIPTION [0010] The present invention discloses various dynamic power supplies for semiconductor devices.", "[0011] FIG. 1 has already been described and discussed as the relevant background to the present invention.", "It requires no further discussion here.", "[0012] FIGS. 2A˜2C are schematic diagrams illustrating three dynamic power supplies according to embodiments of the present invention.", "Memory cells 102 [ 0 :n] illustrated here are 6-T SRAM cells shown in FIG. 1 .", "Between a system high voltage power supply (Vdd) and a cells'", "high voltage power supply Vcc line 106 , a block 202 is coupled.", "[0013] Referring to FIG. 2A , in a first embodiment of the present invention, the block 202 may be implemented as a PMOS transistor 212 and a capacitor 214 .", "A drain, a source, a gate and a bulk of the PMOS transistor 212 are coupled to the Vdd, the Vcc line 160 , the block 204 at a node 216 and the Vdd, respectively.", "The capacitor 214 is coupled between the Vcc line 160 and the block 204 at node 218 .", "During non-access or standby periods, node 216 is in a logic LOW state, and the PMOS transistor 212 is on, so that the Vcc is approximately equal to the Vdd.", "During writing the SRAM cell 102 periods, node 216 is temporarily turned to a HIGH logic state, which then shut off the PMOS transistor 212 , so that the Vcc line 160 becomes floating during the short writing period.", "Charges previously stored in the Vcc line 160 embark on a discharging process, therefore, the voltages at the floating Vcc line 160 will begin to drop, which is a favorable condition for writing.", "Additionally, prior to the writing period, node 218 is kept at the Vdd, hence no charge is stored in the capacitor 214 .", "Once entering the writing period, node 218 is temporarily turned to a voltage lower than the Vdd, such as Vss, which will force the voltage at the Vcc line 160 to drop even faster than a case where only the PMOS transistor 212 alone is employed.", "[0014] During reading the SRAM cell 102 periods, node 216 remains at the logic LOW state, which turns on the PMOS transistor 212 , therefore, the Vdd supplies the Vcc line 160 .", "But prior to the actual reading, node 218 is kept at a voltage lower than the Vdd, so that the capacitor 214 is charged.", "Upon a start of the reading, node 218 is switched from the low voltage to the Vdd, so that the capacitor 214 provides a voltage boost to the Vcc line 160 .", "As discussed earlier, higher Vcc voltage is favorable to reading the SRAM cell 120 .", "[0015] Referring to FIG. 2B , in a second embodiment of the present invention, the block 202 may be implemented as just a PMOS transistor 222 with a source, a drain, a gate and a bulk coupled to the Vdd, the Vcc line 160 , to a block 204 at node 226 and the Vcc line 160 , respectively.", "Similar to the first embodiment, the PMOS transistor 222 is turned on during reading the SRAM cell 102 , and turned off during writing the SRAM cell 102 by the block 204 .", "When the PMOS transistor 222 is on, the Vcc line 160 is driven by the Vdd, which is a favorable condition for reading.", "When the PMOS transistor 222 is off, the Vcc line 160 is floating, which is a favorable condition for writing.", "Beside the second embodiment does not employ a boost capacitor 214 as shown in FIG. 2A , the second embodiment differs from the first embodiment in that the bulk of the PMOS transistor 222 is coupled to the Vcc line 160 , or the drain of itself.", "As a result, when the PMOS transistor 222 is on, there is a voltage drop across its source and drain.", "The magnitude of the voltage drop equals approximately its threshold voltage.", "This lowered Vcc voltage condition is desirable for lowering standby leakage of the SRAM cells 102 .", "[0016] Referring to FIG. 2C , in a third embodiment of the present invention, the block 202 may be implemented as a PMOS transistor 232 and a capacitor 234 .", "A source, a drain, a gate and a bulk of the PMOS transistor 232 are coupled to the Vdd, the Vcc line 160 , to a block 204 at node 236 and the Vcc line 160 , respectively.", "Apparently, the connection of the PMOS transistor 232 is the same as the PMOS transistor 222 in the second embodiment.", "According the third embodiment, the PMOS transistor 232 also functions the same as the PMOS transistor 222 , i.e., the PMOS transistor 232 is turned on during reading the SRAM cell 102 , and turned off during writing the SRAM cell 102 by the block 204 .", "When the PMOS transistor 232 is on, the Vcc line 160 is driven by the Vdd, which is a favorable condition for reading.", "When the PMOS transistor 232 is off, the Vcc line 160 is floating, which is a favorable condition for writing.", "Since the bulk of the PMOS transistor 232 is coupled to the Vcc line 160 , or the drain of itself.", "As a result, when the PMOS transistor 232 is on, there is a voltage drop across its source and drain.", "The magnitude of the voltage drop equals approximately its threshold voltage.", "This lowered Vcc voltage condition is desirable for lowering standby leakage of the SRAM cells 102 .", "[0017] Then there is the boost capacitor 234 , which is connected the same as the capacitor 214 in the first embodiment.", "According to the third embodiment, the capacitor 234 also functions the same as the capacitor 214 , i.e., during writing the capacitor 234 helps pulling down the voltage at the floated Vcc line 160 , and during reading, the charge previously stored in the capacitor 234 provides a boost to the voltage at the Vcc line 160 , which is driven by the Vdd in reading case.", "[0018] Referring the FIGS. 2A˜2C , the blocks 204 are not provided with any detailed implementations, as one skilled in the art would have no difficulty to construct circuits to provide signals at the corresponding nodes 216 , 218 , 226 , 236 and 238 for these blocks.", "The functions of these signals are described in above paragraphs.", "Typically the blocks 204 may contain inverters, NOR and NAND gates, etc.", "[0019] The capacitor, 214 or 234 , may be formed by any appropriately available semiconductor materials in a die for a given process, such as metal-intermetal dielectric-metal (MiM), metal-oxide-semiconductor (MOS) or polysilicon-interpoly dielectric-polysilicon (PiP).", "[0020] With this PMOS transistor switching and capacitor voltage boosting capacities, the power supply to the SRAM cells may be dynamically managed to mean the contradictory demands of the reading and writing operations.", "[0021] Although the embodiments show only the SRAM cell as a recipient of the dynamic power supplies, and only the Vdd is switched according to the present invention, one having skill in the art would appreciate that the present invention may be applied to other memories or even logic circuits where contradictory voltage conditions are desired in different operations, and the Vss power supply can be similarly switched.", "[0022] The above illustration provides many different embodiments or embodiments for implementing different features of the invention.", "Specific embodiments of components and processes are described to help clarify the invention.", "These are, of course, merely embodiments and are not intended to limit the invention from that described in the claims.", "[0023] Although the invention is illustrated and described herein as embodied in one or more specific examples, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.", "Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention, as set forth in the following claims." ]
The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the U.S. Department of Energy and the University of California, for the operation of Lawrence Livermore National Laboratory. BACKGROUND OF THE INVENTION The invention relates generally to removal of metal in the formation of planarized interconnects for integrated circuits, and more particularly to method and apparatus for electro-removal, including generally electrochemical etching and particularly electropolishing. Electropolishing is a method of polishing metal surfaces by applying an electric current through an electrolytic bath, as described for example in McGraw-Hill Encyclopedia of Science & Technology, pp. 810-811, 1982. The process is the reverse of electroplating. Anodic dissolution of surface features produces a flat, smooth, brilliant surface. Current density on the work surface is an important parameter. Below a certain voltage level, etching occurs. Above the etching voltage level, a constant current region is reached where polishing occurs. At even higher voltage, oxygen evolution interferes with polishing. The invention applies particularly to electropolishing, but can also be applied to electrolytic etching or electrochemical removal by varying the operating parameters from the polishing region. In the fabrication of multilevel integrated circuit structures, the planarization of each metal layer, e.g., by pulsed laser or other heating as shown in U.S. Pat. Nos. 4,674,176 and 4,681,795 to Tuckerman, eliminates irregular and discontinuous conditions between successive layers, particularly where vias are located. To achieve fully planar multilevel interconnects, the dielectric layer must also be planarized, or the metal layer can be etched back so that it is flush with the dielectric layer. U.S. Pat. No. 3,849,270 to Takagi et al. describes a process of manufacturing semiconductor devices using electrolytic etching to remove a coating layer from an insulating layer. U.S. patent application Ser. No. 348,982 filed May 8, 1989, by Bernhardt et al. for Electrochemical Planarization describes a method and apparatus for forming a thin film planarized metal interconnect which is flush with the surrounding dielectric layer. In a preferred embodiment, a planarized metal layer is formed by controlled deposition, using an isotropic or other self-planarizing process, of a layer having a depth at least about half the width of the widest feature to be filled in the dielectric layer. The metal layer is then etched back by electropolishing. In the electrochemical planarization process of U.S. patent application Ser. No. 348,982 filed May 8, 1989 is it essential that the etchback rate be substantially the same everywhere on the surface. The etchback process of preference is electropolishing because the etching rate can be high, the surface is polished (i.e. smoothed) in the process and the associated equipment is relatively inexpensive. SUMMARY OF THE INVENTION A primary object of the invention is to provide a spatially uniform polishing, etching or removal rate. To accomplish this, both edge effects and larger spatial non-uniformities are controlled. A second object of the invention is to polish the surface, that is, to reduce surface roughness at the same time as etching it. A third object of the invention is to remove material from the surface rapidly. Some advantages of the preferred embodiment are: 1) very high polishing rates (upwards of 1 μm/min) with excellent uniformity (about 1%; 2) a constant rate of removal after a short initial transient; and 3) easy end point detection. In electropolishing copper, for example, the etching or removal rate is limited by the formation of a dense layer. Controlling the diffusion of metal ions into the bulk of the polishing solution can significantly affect the etching or removal rate and its spatial uniformity. The invention is a method and apparatus for electropolishing or otherwise electrolytically etching a sample or workpiece. The electropolishing apparatus or cell is formed of a containment vessel filled with electropolishing solution. The workpiece or sample is mounted in a holder, together forming an extended anode, which prevents edge effects at the workpiece. The sample is held in place on the sample holder by any suitable retaining means such as retaining clips. The inner portion of the sample holder is recessed to a depth equal to the sample thickness so that when the sample is placed into the sample holder, the outer portion (top surface) will be flush with the sample surface. The anode is typically rotatable, and is preferably oriented horizontally facing down, which results in high electropolishing rates. The anode is separated from the cathode to prevent bubble transport to the anode and to produce a uniform current distribution at the anode. For these purposes, a solid nonconducting anode-cathode barrier or cup is placed within the cell containment vessel. The anode extends into the top of the cup. The cathode is outside of the cup. A virtual cathode hole is formed in the bottom of the cup, below the level of the cathode, permitting current flow while preventing bubble transport to the anode. Heat removal may be performed either internal or external to the cell. A reference electrode can be used to control cell voltage. End point detection and current shutoff can be used to stop polishing at the desired point. By etching so that the edge clears first, the change in reflectance or color of an underlying adhesion layer can be detected, or electrical contact can be broken. BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: FIG. 1A is a perspective view of an electropolishing apparatus according to the invention, and FIG. 1B is a horizontal cross-sectional view taken along line A--A of FIG. 1A. FIG. 2 is a perspective and assembly view of the extended anode. FIG. 3 is a diagram showing the calculated primary current distribution within the electropolishing apparatus. FIG. 4A is a perspective assembly view of a sample with end point ring, and FIG. 4B is a vertical cross-sectional view of the sample taken along line A--A of FIG. 4A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electropolishing apparatus (cell) 10 according to the invention is shown in FIGS. 1A, B. Cell 10 is formed of a containment vessel or tank (cell body) 11 filled with electropolishing solution 12. The invention is primarily described in terms of electropolishing; however, the method and apparatus can also be used for electrochemical etching (electro-removal) in general. Therefore, a reference to polishing may also be interpreted as etching or removal, except where clearly limited from the context. For illustrative purposes, the polishing of copper using the apparatus of FIGS. 1A, B is described. For copper an electropolishing solution is composed of phosphoric acid which contains a fraction of water which can be adjusted to optimize the electropolishing rate with respect to other polishing properties such as surface smoothness. For other materials the solution might be different, e.g., hydrochloric acid in glycerine can be used for electropolishing gold. Other solutions can also be used for copper. Important physical properties of the solution are its viscosity and its electrical conductivity. The sample to be polished (the "workpiece" or anode) is mounted into a holder, with which it forms an extended anode 14, in the sense that the surface of the holder nearest to the workpiece is made of the material to be electropolished, in this example copper, and is electropolished along with the workpiece. A particular embodiment of the extended anode is shown in FIG. 2. The extended anode 14 is formed of a copper wafer holder 16 on which the workpiece or sample (e.g., wafer) 18 is held. The sample 18 is held in place by retaining means such as clips 22, which are preferably made of the material being polished. Holder 16 has an outer portion 17 and a recessed inner region 19. Sample 18 fits into region 19 so that the upper surface of sample 18 is flush with the upper surface of outer portion 17, thereby extending the anode surface. Although holder 16 is typically circular in shape, noncircular samples 18 can be held by forming the recessed region 19 of suitable shape. This extended anode arrangement removes edge or loading effects from the edge of the workpiece to the surface of the holder. (At the boundary between the polishable material and inert surfaces, or at physical edges, polishable material near the edge is removed faster than the polishable material far from the edge.) By varying the size of the border of polishable material on the holder, it is possible to control the electropolishing rate at the edge of the workpiece with respect to that at interior regions. One can simply make these rates substantially equal or one can let the workpiece edge polish controllably faster for some purpose such as end point detection, as described herein. In addition, by varying the flow rate of electrolyte impinging on the center of the sample, the rate at the center can be increased with respect to that at the edge. Anode 14 is attached to a shaft 15 of FIG. 1A so that the anode 14 can be rotated by means of motor 33. In the apparatus of FIG. 1A, the anode 14 is positioned horizontally with the workpiece surface facing downward in the Earth's gravitational field. This arrangement has the advantage that the "copper phosphate" layer which forms during electropolishing at the anode surface, being more dense than the bulk of the electropolishing solution, can fall away from that surface and redissolve more quickly than if the anode surface had another orientation (as, for example, shown in the apparatus of Ser. No. 348,982 filed May 8, 1989). This allows higher polishing rates than for other orientations, other parameters such as rotation speed being equal. Another advantage of the inverted anode orientation is the uniformity of polishing rate over the sample (compared, for example, to a vertical anode orientation, in which gravity draws the dense layer across the surface from top to bottom). The preferred embodiment draws upon the concepts associated with a rotating disk electrode (RDE), often used in theoretical studies of kinetics and mass transfer in electrochemical systems. Solutions of the momentum and mass transport of the RDE system are well-known (e.g. J. Newmann, Electrochemical Systems, Prentice-Hall, Englewood N.J., 1973), and demonstrate that under certain conditions, the current distribution to the disk will be uniform. It is, however, essential to provide substantially uniform primary current distribution at the anode. A third advantage of this "face-down" arrangement is the ease with which the workpiece can be placed into and removed from the holder. This accessibility is essential for automation of the process. There are, however, several problems associated with the face-down arrangement, as well as other alternative arrangements, which the invention recognizes and addresses. The first problem is that bubbles formed at the cathode or otherwise introduced into the solution can migrate (rise in the vertical arrangement) and settle on the anode surface. These bubbles will cause local non-uniformities in the anode surface (e.g., unpolished or overpolished spots). To address this problem, the apparatus of FIGS. 1A, B introduces a separation means or barrier between the cathode and the anode through which electrical current can pass, but bubbles cannot. This is accomplished by means of a non-conducting solid barrier (chamber or cup) 28 with a hole or aperture 30 in the bottom. Cathode 32, e.g., a screen, is positioned at the top of the containment vessel 11 external to the anode-cathode barrier 28 and extends, at least partially, around the anode-cathode barrier 28. As shown in FIG. 1B, cathode 32 extends entirely around the inside surface of tank 11, but a portion, e.g., section 24, can be omitted to permit better visual observation of the anode. Anode 14 extends into barrier 28, which defines an anode chamber volume 26 therein. Current can pass through hole 30, but, since the hole 30 is below the level of the cathode 32, no bubbles pass through it and enter the anode chamber volume 26. Instead, bubbles generated by the cathode rise to the surface of the solution over the cathode 32. As shown in FIG. 1A, anode 14 and cathode 32 are electrically connected to a voltage source or power supply 34 (the connection to anode 14 is shown through shaft 15, e.g., by an electrical brush 35). Suitable electrical connection to the workpiece can be made through the anode holder 16, e.g., through clips 22, shown in FIG. 2. Voltage source 34 provides the necessary voltage-current to produce polishing; otherwise, etching will occur. The anode-cathode barrier cup 28 sits on legs 36 above the bottom 21 of containment vessel 11. A reference electrode 31 is immersed in the solution inside the anode-cathode barrier cup 28. Fluid inlets 38 extend into the cell body 11 and through holes 39 in the bottom of cup 28 to inject or remove solution 12 in the interior of cup 28 near anode 14. Fluid outlets 40 also extend into cell body 11 outside cup 28, and act as an inlet or outlet of solution 12 for the cell. Generally, solution is injected into the anode-cathode barrier cup 28 to alter the relative polishing rate uniformity, and is removed from the chamber for filtration purposes. Inlets 38 and outlets 40 can be used to continuously or otherwise recirculate solution 12 through the cell. For example, solution removed through an outlet 40 may be filtered by filter 29, then placed in reservoir 25, from which it is pumped by pump 23 through inlet 38 into chamber 28. Filter 29 can also be combined with or replaced by a cooling chamber, as further described herein. A constantly rotating anode (particularly in the face down orientation) tends to generate a wavy surface, analogous to the "accordion instability" which produces periodic humps in roads travelled by heavy trucks. This phenomena can be reduced by minimizing the rotation of the fluid which will naturally arise in the anode-cathode barrier cup compartment by either: 1) adding fluid with no rotational inertia into the chamber, along the natural flow lines which impinge on the anode 14 (as accomplished by fluid inlets 38); or 2) adding baffles 37 to the bath whose size and shape minimize the tendency of the fluid to spin in the chamber, but do not significantly alter the overall primary current distribution. Experimentally, it has been determined that these baffles can extend from the wall of the anode-cathode barrier cup toward the center of the cup to the virtual cathode hole 30, thereby completely eliminating spiral formation without altering the current distribution. The material of the anode-cathode cup also serves as a barrier to the flow of charge. The hole in the bottom of the cup functions as a virtual cathode in the sense that all the current must pass through the hole. The primary current distribution at the anode is strongly influenced by the dimensions of the hole and is important in achieving the desired uniformity of polishing rate at the anode, as shown in FIG. 3. A graph of the primary current distribution through the diameter of a vertical cross-section of cell 10 with a particular set of geometric parameters is shown in FIG. 3. The displayed contour lines are of constant current flux. Adjacent lines are separated by regions in which the flux differs by 5%. The sample 18 (inside extended anode 14) is wholly within a 5% region. Generally, the diameter of the hole must be smaller than the workpiece and it must be separated from the anode by a distance larger than the largest anode dimension. However, the hole must not be so small as to cause charge crowding near its edge (thereby significantly increasing the overall cell resistance), nor so large that the distance from the edge of the hole to the edge of the anode is significantly smaller than that from the edge of the hole to the center of the anode. Dimensions can be optimized by calculating the primary current distribution to maximize the desired level of current uniformity. The actual current distribution will be best when the primary (ohmic), secondary (kinetic), and tertiary (diffusion controlled) current distributions are all substantially uniform. Because a significant amount of heat is generated inside the apparatus, the temperature of the cell will rise during its use if means for the removal of this heat are not available. Generally, the rate and operating voltage of electropolishing are changed by the cell temperature. Therefore, to maintain a controlled electropolishing rate, it is necessary to install a heat exchange mechanism for this system. Two possible embodiments are to have cooling coils 41 inside the bath, as shown in FIG. 1A, or to cool the electrolyte externally of the cell, e.g., combining or replacing the filtration line with a cooling chamber 29 or cooling the reservoir 25. It is also preferred that the voltage of the cell be controlled by a "three electrode system". In such a system, the voltage of the anode is set and maintained with respect to an unpolarized reference electrode 31 of FIG. 1A (i.e., an electrode through which no d.c. current passes), but the anode surface voltage is driven by varying the potential of the cathode. Such a system ensures the electrochemical stability of the anode interface from being thrown into a potential regime where unwanted side reactions occur (e.g., oxygen evolution at the anode), as well as provides a controlled approach to surface film formation and steady state electropolishing. It is another object of the apparatus to provide for end point detection and current shut-off. It is desirable to leave a small amount of copper on the workpiece because the polishing rate for isolated structures (such as embedded lines) can be much greater than for a surface completely covered with the metal being polished. If the metal of the unpatterned areas is permitted to clear, the embedded, planarized features will be etched more than desired. One method of detecting when the unpatterned areas are about to clear is to observe a change in the reflectivity of the surface near the edge of the sample. If slightly less material is deposited at the edge of the sample or the polishing rate is slightly greater at the edge, then the metal will clear there first. In one preferred embodiment, an adhesion layer (e.g., of Cr or Ti) is sputtered onto a silicon or silicon oxide substrate. After the sputtering of a thin "seed" layer of copper metal onto this adhesion layer, copper is electroplated onto the substrate. When the copper is finally polished away at the edge, this adhesion layer is exposed. Since the adhesion layer is silver or "metallic" in color, it is easily distinguishable from copper. The adhesion layer is not substantially attacked by the electropolishing process. A difference in the reflectivity or color of the substrate with respect to that of the material being polished can therefore be observed and the current shut off. For example, a suitable optical instrument can be use to observe this change and automatically shut the current off. As shown in FIG. 1A, fiber optic probe 42 can be set nearby and facing the portion of the anode which clears first and an appropriate optical instrument 44 is placed on the other end of the fiber optic 43 to detect the reflectivity change. Instrument 44 is electrically connected to power supply 34 to shut off the current. In a preferred embodiment, the barrier cup and the containment vessel are made of glass, and there is a separation in the cathode so that the anode can be viewed from outside the apparatus. The functions of the end point detector and the automatic current shut-off can be combined. If the connection between the sample and the power supply is through the metal being polished and is located near the edge of the sample, then by making the metal at the edge clear first, the current path to the sample is also severed. An embodiment of such an arrangement is illustrated in FIGS. 4A, B. Preferably, a "retaining" ring 20 is placed over the workpiece 18 and both are held on holder 16 by retaining clips 22 through which anode current is provided to the sample 18, in order to provide more uniform electrical contact to the sample, as shown in FIG. 4A. Retaining ring 20 is formed of an outer portion 46 and a recessed inner portion 48. Sample 18 fits into recessed portion 48. A detailed illustrative workpiece structure is shown in FIG. 4B. The penultimate layer 50 of the substrate (workpiece 18) is an insulator (e.g., undoped Si or SiO 2 ) onto which an adhesion layer 51 is added (e.g., by sputtering) everywhere except near the edge. Next, a seed layer 52 of the metal to be polished is added. During electropolishing, the edges clear first, and since the electrical contacts are made at the edge, the current path is severed before the center of the sample clears. For example, the edge portion 53 is etched down to insulating layer 50 before the rest of metal layer 52 is etched away. Since electrical contact to metal layer 52 is through edge portion 53, polishing stops when edge portion 53 has been totally etched away. Electrical contact is maintained with the edge portion by suitable clips or other contacts, which stay in contact while the layer is being etched away. Inner portion 48 of ring 20 contacts workpiece 18 at the edge of edge portion 53, with outer portion 46 extending out from workpiece 18 and down to holder 16. The part of edge portion 53 not covered by inner portion 46 will etch down to layer 50 and thus break electrical contact to the interior of layer 52. In an illustrative embodiment, the tank is 16" in diameter and 91/2" high. The barrier cup is 61/2" high, has an inside diameter of 91/4", and an outside diameter of 10". The cup thus sits 3" above the bottom of the tank. Both are made of glass. The virtual cathode hole is 2" in diameter. The workpiece is 4" in diameter and the extended anode is 6" in diameter so there is a 1" sacrificial edge around the workpiece. The cathode screen is 4" high and extends from the top of the tank. The anode is near the top of the tank. Changes and modifications in the specifically described embodiments can be carried out without departing from the scope of the invention which is intended to be limited only by the scope of the appended claims.
In an electropolishing or electrolytic etching apparatus the anode is separated from the cathode to prevent bubble transport to the anode and to produce a uniform current distribution at the anode by means of a solid nonconducting anode-cathode barrier. The anode extends into the top of the barrier and the cathode is outside the barrier. A virtual cathode hole formed in the bottom of the barrier below the level of the cathode permits current flow while preventing bubble transport. The anode is rotatable and oriented horizontally facing down. An extended anode is formed by mounting the workpiece in a holder which extends the electropolishing or etching area beyond the edge of the workpiece to reduce edge effects at the workpiece. A reference electrode controls cell voltage. Endpoint detection and current shut-off stop polishing. Spatially uniform polishing or etching can be rapidly performed.
Summarize the key points of the given patent document.
[ "The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the U.S. Department of Energy and the University of California, for the operation of Lawrence Livermore National Laboratory.", "BACKGROUND OF THE INVENTION The invention relates generally to removal of metal in the formation of planarized interconnects for integrated circuits, and more particularly to method and apparatus for electro-removal, including generally electrochemical etching and particularly electropolishing.", "Electropolishing is a method of polishing metal surfaces by applying an electric current through an electrolytic bath, as described for example in McGraw-Hill Encyclopedia of Science &", "Technology, pp. 810-811, 1982.", "The process is the reverse of electroplating.", "Anodic dissolution of surface features produces a flat, smooth, brilliant surface.", "Current density on the work surface is an important parameter.", "Below a certain voltage level, etching occurs.", "Above the etching voltage level, a constant current region is reached where polishing occurs.", "At even higher voltage, oxygen evolution interferes with polishing.", "The invention applies particularly to electropolishing, but can also be applied to electrolytic etching or electrochemical removal by varying the operating parameters from the polishing region.", "In the fabrication of multilevel integrated circuit structures, the planarization of each metal layer, e.g., by pulsed laser or other heating as shown in U.S. Pat. Nos. 4,674,176 and 4,681,795 to Tuckerman, eliminates irregular and discontinuous conditions between successive layers, particularly where vias are located.", "To achieve fully planar multilevel interconnects, the dielectric layer must also be planarized, or the metal layer can be etched back so that it is flush with the dielectric layer.", "U.S. Pat. No. 3,849,270 to Takagi et al.", "describes a process of manufacturing semiconductor devices using electrolytic etching to remove a coating layer from an insulating layer.", "U.S. patent application Ser.", "No. 348,982 filed May 8, 1989, by Bernhardt et al.", "for Electrochemical Planarization describes a method and apparatus for forming a thin film planarized metal interconnect which is flush with the surrounding dielectric layer.", "In a preferred embodiment, a planarized metal layer is formed by controlled deposition, using an isotropic or other self-planarizing process, of a layer having a depth at least about half the width of the widest feature to be filled in the dielectric layer.", "The metal layer is then etched back by electropolishing.", "In the electrochemical planarization process of U.S. patent application Ser.", "No. 348,982 filed May 8, 1989 is it essential that the etchback rate be substantially the same everywhere on the surface.", "The etchback process of preference is electropolishing because the etching rate can be high, the surface is polished (i.e. smoothed) in the process and the associated equipment is relatively inexpensive.", "SUMMARY OF THE INVENTION A primary object of the invention is to provide a spatially uniform polishing, etching or removal rate.", "To accomplish this, both edge effects and larger spatial non-uniformities are controlled.", "A second object of the invention is to polish the surface, that is, to reduce surface roughness at the same time as etching it.", "A third object of the invention is to remove material from the surface rapidly.", "Some advantages of the preferred embodiment are: 1) very high polishing rates (upwards of 1 μm/min) with excellent uniformity (about 1%;", "2) a constant rate of removal after a short initial transient;", "and 3) easy end point detection.", "In electropolishing copper, for example, the etching or removal rate is limited by the formation of a dense layer.", "Controlling the diffusion of metal ions into the bulk of the polishing solution can significantly affect the etching or removal rate and its spatial uniformity.", "The invention is a method and apparatus for electropolishing or otherwise electrolytically etching a sample or workpiece.", "The electropolishing apparatus or cell is formed of a containment vessel filled with electropolishing solution.", "The workpiece or sample is mounted in a holder, together forming an extended anode, which prevents edge effects at the workpiece.", "The sample is held in place on the sample holder by any suitable retaining means such as retaining clips.", "The inner portion of the sample holder is recessed to a depth equal to the sample thickness so that when the sample is placed into the sample holder, the outer portion (top surface) will be flush with the sample surface.", "The anode is typically rotatable, and is preferably oriented horizontally facing down, which results in high electropolishing rates.", "The anode is separated from the cathode to prevent bubble transport to the anode and to produce a uniform current distribution at the anode.", "For these purposes, a solid nonconducting anode-cathode barrier or cup is placed within the cell containment vessel.", "The anode extends into the top of the cup.", "The cathode is outside of the cup.", "A virtual cathode hole is formed in the bottom of the cup, below the level of the cathode, permitting current flow while preventing bubble transport to the anode.", "Heat removal may be performed either internal or external to the cell.", "A reference electrode can be used to control cell voltage.", "End point detection and current shutoff can be used to stop polishing at the desired point.", "By etching so that the edge clears first, the change in reflectance or color of an underlying adhesion layer can be detected, or electrical contact can be broken.", "BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: FIG. 1A is a perspective view of an electropolishing apparatus according to the invention, and FIG. 1B is a horizontal cross-sectional view taken along line A--A of FIG. 1A.", "FIG. 2 is a perspective and assembly view of the extended anode.", "FIG. 3 is a diagram showing the calculated primary current distribution within the electropolishing apparatus.", "FIG. 4A is a perspective assembly view of a sample with end point ring, and FIG. 4B is a vertical cross-sectional view of the sample taken along line A--A of FIG. 4A.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electropolishing apparatus (cell) 10 according to the invention is shown in FIGS. 1A, B. Cell 10 is formed of a containment vessel or tank (cell body) 11 filled with electropolishing solution 12.", "The invention is primarily described in terms of electropolishing;", "however, the method and apparatus can also be used for electrochemical etching (electro-removal) in general.", "Therefore, a reference to polishing may also be interpreted as etching or removal, except where clearly limited from the context.", "For illustrative purposes, the polishing of copper using the apparatus of FIGS. 1A, B is described.", "For copper an electropolishing solution is composed of phosphoric acid which contains a fraction of water which can be adjusted to optimize the electropolishing rate with respect to other polishing properties such as surface smoothness.", "For other materials the solution might be different, e.g., hydrochloric acid in glycerine can be used for electropolishing gold.", "Other solutions can also be used for copper.", "Important physical properties of the solution are its viscosity and its electrical conductivity.", "The sample to be polished (the "workpiece"", "or anode) is mounted into a holder, with which it forms an extended anode 14, in the sense that the surface of the holder nearest to the workpiece is made of the material to be electropolished, in this example copper, and is electropolished along with the workpiece.", "A particular embodiment of the extended anode is shown in FIG. 2. The extended anode 14 is formed of a copper wafer holder 16 on which the workpiece or sample (e.g., wafer) 18 is held.", "The sample 18 is held in place by retaining means such as clips 22, which are preferably made of the material being polished.", "Holder 16 has an outer portion 17 and a recessed inner region 19.", "Sample 18 fits into region 19 so that the upper surface of sample 18 is flush with the upper surface of outer portion 17, thereby extending the anode surface.", "Although holder 16 is typically circular in shape, noncircular samples 18 can be held by forming the recessed region 19 of suitable shape.", "This extended anode arrangement removes edge or loading effects from the edge of the workpiece to the surface of the holder.", "(At the boundary between the polishable material and inert surfaces, or at physical edges, polishable material near the edge is removed faster than the polishable material far from the edge.) By varying the size of the border of polishable material on the holder, it is possible to control the electropolishing rate at the edge of the workpiece with respect to that at interior regions.", "One can simply make these rates substantially equal or one can let the workpiece edge polish controllably faster for some purpose such as end point detection, as described herein.", "In addition, by varying the flow rate of electrolyte impinging on the center of the sample, the rate at the center can be increased with respect to that at the edge.", "Anode 14 is attached to a shaft 15 of FIG. 1A so that the anode 14 can be rotated by means of motor 33.", "In the apparatus of FIG. 1A, the anode 14 is positioned horizontally with the workpiece surface facing downward in the Earth's gravitational field.", "This arrangement has the advantage that the "copper phosphate"", "layer which forms during electropolishing at the anode surface, being more dense than the bulk of the electropolishing solution, can fall away from that surface and redissolve more quickly than if the anode surface had another orientation (as, for example, shown in the apparatus of Ser.", "No. 348,982 filed May 8, 1989).", "This allows higher polishing rates than for other orientations, other parameters such as rotation speed being equal.", "Another advantage of the inverted anode orientation is the uniformity of polishing rate over the sample (compared, for example, to a vertical anode orientation, in which gravity draws the dense layer across the surface from top to bottom).", "The preferred embodiment draws upon the concepts associated with a rotating disk electrode (RDE), often used in theoretical studies of kinetics and mass transfer in electrochemical systems.", "Solutions of the momentum and mass transport of the RDE system are well-known (e.g. J. Newmann, Electrochemical Systems, Prentice-Hall, Englewood N.J., 1973), and demonstrate that under certain conditions, the current distribution to the disk will be uniform.", "It is, however, essential to provide substantially uniform primary current distribution at the anode.", "A third advantage of this "face-down"", "arrangement is the ease with which the workpiece can be placed into and removed from the holder.", "This accessibility is essential for automation of the process.", "There are, however, several problems associated with the face-down arrangement, as well as other alternative arrangements, which the invention recognizes and addresses.", "The first problem is that bubbles formed at the cathode or otherwise introduced into the solution can migrate (rise in the vertical arrangement) and settle on the anode surface.", "These bubbles will cause local non-uniformities in the anode surface (e.g., unpolished or overpolished spots).", "To address this problem, the apparatus of FIGS. 1A, B introduces a separation means or barrier between the cathode and the anode through which electrical current can pass, but bubbles cannot.", "This is accomplished by means of a non-conducting solid barrier (chamber or cup) 28 with a hole or aperture 30 in the bottom.", "Cathode 32, e.g., a screen, is positioned at the top of the containment vessel 11 external to the anode-cathode barrier 28 and extends, at least partially, around the anode-cathode barrier 28.", "As shown in FIG. 1B, cathode 32 extends entirely around the inside surface of tank 11, but a portion, e.g., section 24, can be omitted to permit better visual observation of the anode.", "Anode 14 extends into barrier 28, which defines an anode chamber volume 26 therein.", "Current can pass through hole 30, but, since the hole 30 is below the level of the cathode 32, no bubbles pass through it and enter the anode chamber volume 26.", "Instead, bubbles generated by the cathode rise to the surface of the solution over the cathode 32.", "As shown in FIG. 1A, anode 14 and cathode 32 are electrically connected to a voltage source or power supply 34 (the connection to anode 14 is shown through shaft 15, e.g., by an electrical brush 35).", "Suitable electrical connection to the workpiece can be made through the anode holder 16, e.g., through clips 22, shown in FIG. 2. Voltage source 34 provides the necessary voltage-current to produce polishing;", "otherwise, etching will occur.", "The anode-cathode barrier cup 28 sits on legs 36 above the bottom 21 of containment vessel 11.", "A reference electrode 31 is immersed in the solution inside the anode-cathode barrier cup 28.", "Fluid inlets 38 extend into the cell body 11 and through holes 39 in the bottom of cup 28 to inject or remove solution 12 in the interior of cup 28 near anode 14.", "Fluid outlets 40 also extend into cell body 11 outside cup 28, and act as an inlet or outlet of solution 12 for the cell.", "Generally, solution is injected into the anode-cathode barrier cup 28 to alter the relative polishing rate uniformity, and is removed from the chamber for filtration purposes.", "Inlets 38 and outlets 40 can be used to continuously or otherwise recirculate solution 12 through the cell.", "For example, solution removed through an outlet 40 may be filtered by filter 29, then placed in reservoir 25, from which it is pumped by pump 23 through inlet 38 into chamber 28.", "Filter 29 can also be combined with or replaced by a cooling chamber, as further described herein.", "A constantly rotating anode (particularly in the face down orientation) tends to generate a wavy surface, analogous to the "accordion instability"", "which produces periodic humps in roads travelled by heavy trucks.", "This phenomena can be reduced by minimizing the rotation of the fluid which will naturally arise in the anode-cathode barrier cup compartment by either: 1) adding fluid with no rotational inertia into the chamber, along the natural flow lines which impinge on the anode 14 (as accomplished by fluid inlets 38);", "or 2) adding baffles 37 to the bath whose size and shape minimize the tendency of the fluid to spin in the chamber, but do not significantly alter the overall primary current distribution.", "Experimentally, it has been determined that these baffles can extend from the wall of the anode-cathode barrier cup toward the center of the cup to the virtual cathode hole 30, thereby completely eliminating spiral formation without altering the current distribution.", "The material of the anode-cathode cup also serves as a barrier to the flow of charge.", "The hole in the bottom of the cup functions as a virtual cathode in the sense that all the current must pass through the hole.", "The primary current distribution at the anode is strongly influenced by the dimensions of the hole and is important in achieving the desired uniformity of polishing rate at the anode, as shown in FIG. 3. A graph of the primary current distribution through the diameter of a vertical cross-section of cell 10 with a particular set of geometric parameters is shown in FIG. 3. The displayed contour lines are of constant current flux.", "Adjacent lines are separated by regions in which the flux differs by 5%.", "The sample 18 (inside extended anode 14) is wholly within a 5% region.", "Generally, the diameter of the hole must be smaller than the workpiece and it must be separated from the anode by a distance larger than the largest anode dimension.", "However, the hole must not be so small as to cause charge crowding near its edge (thereby significantly increasing the overall cell resistance), nor so large that the distance from the edge of the hole to the edge of the anode is significantly smaller than that from the edge of the hole to the center of the anode.", "Dimensions can be optimized by calculating the primary current distribution to maximize the desired level of current uniformity.", "The actual current distribution will be best when the primary (ohmic), secondary (kinetic), and tertiary (diffusion controlled) current distributions are all substantially uniform.", "Because a significant amount of heat is generated inside the apparatus, the temperature of the cell will rise during its use if means for the removal of this heat are not available.", "Generally, the rate and operating voltage of electropolishing are changed by the cell temperature.", "Therefore, to maintain a controlled electropolishing rate, it is necessary to install a heat exchange mechanism for this system.", "Two possible embodiments are to have cooling coils 41 inside the bath, as shown in FIG. 1A, or to cool the electrolyte externally of the cell, e.g., combining or replacing the filtration line with a cooling chamber 29 or cooling the reservoir 25.", "It is also preferred that the voltage of the cell be controlled by a "three electrode system".", "In such a system, the voltage of the anode is set and maintained with respect to an unpolarized reference electrode 31 of FIG. 1A (i.e., an electrode through which no d.c. current passes), but the anode surface voltage is driven by varying the potential of the cathode.", "Such a system ensures the electrochemical stability of the anode interface from being thrown into a potential regime where unwanted side reactions occur (e.g., oxygen evolution at the anode), as well as provides a controlled approach to surface film formation and steady state electropolishing.", "It is another object of the apparatus to provide for end point detection and current shut-off.", "It is desirable to leave a small amount of copper on the workpiece because the polishing rate for isolated structures (such as embedded lines) can be much greater than for a surface completely covered with the metal being polished.", "If the metal of the unpatterned areas is permitted to clear, the embedded, planarized features will be etched more than desired.", "One method of detecting when the unpatterned areas are about to clear is to observe a change in the reflectivity of the surface near the edge of the sample.", "If slightly less material is deposited at the edge of the sample or the polishing rate is slightly greater at the edge, then the metal will clear there first.", "In one preferred embodiment, an adhesion layer (e.g., of Cr or Ti) is sputtered onto a silicon or silicon oxide substrate.", "After the sputtering of a thin "seed"", "layer of copper metal onto this adhesion layer, copper is electroplated onto the substrate.", "When the copper is finally polished away at the edge, this adhesion layer is exposed.", "Since the adhesion layer is silver or "metallic"", "in color, it is easily distinguishable from copper.", "The adhesion layer is not substantially attacked by the electropolishing process.", "A difference in the reflectivity or color of the substrate with respect to that of the material being polished can therefore be observed and the current shut off.", "For example, a suitable optical instrument can be use to observe this change and automatically shut the current off.", "As shown in FIG. 1A, fiber optic probe 42 can be set nearby and facing the portion of the anode which clears first and an appropriate optical instrument 44 is placed on the other end of the fiber optic 43 to detect the reflectivity change.", "Instrument 44 is electrically connected to power supply 34 to shut off the current.", "In a preferred embodiment, the barrier cup and the containment vessel are made of glass, and there is a separation in the cathode so that the anode can be viewed from outside the apparatus.", "The functions of the end point detector and the automatic current shut-off can be combined.", "If the connection between the sample and the power supply is through the metal being polished and is located near the edge of the sample, then by making the metal at the edge clear first, the current path to the sample is also severed.", "An embodiment of such an arrangement is illustrated in FIGS. 4A, B. Preferably, a "retaining"", "ring 20 is placed over the workpiece 18 and both are held on holder 16 by retaining clips 22 through which anode current is provided to the sample 18, in order to provide more uniform electrical contact to the sample, as shown in FIG. 4A.", "Retaining ring 20 is formed of an outer portion 46 and a recessed inner portion 48.", "Sample 18 fits into recessed portion 48.", "A detailed illustrative workpiece structure is shown in FIG. 4B.", "The penultimate layer 50 of the substrate (workpiece 18) is an insulator (e.g., undoped Si or SiO 2 ) onto which an adhesion layer 51 is added (e.g., by sputtering) everywhere except near the edge.", "Next, a seed layer 52 of the metal to be polished is added.", "During electropolishing, the edges clear first, and since the electrical contacts are made at the edge, the current path is severed before the center of the sample clears.", "For example, the edge portion 53 is etched down to insulating layer 50 before the rest of metal layer 52 is etched away.", "Since electrical contact to metal layer 52 is through edge portion 53, polishing stops when edge portion 53 has been totally etched away.", "Electrical contact is maintained with the edge portion by suitable clips or other contacts, which stay in contact while the layer is being etched away.", "Inner portion 48 of ring 20 contacts workpiece 18 at the edge of edge portion 53, with outer portion 46 extending out from workpiece 18 and down to holder 16.", "The part of edge portion 53 not covered by inner portion 46 will etch down to layer 50 and thus break electrical contact to the interior of layer 52.", "In an illustrative embodiment, the tank is 16"", "in diameter and 91/2"", "high.", "The barrier cup is 61/2"", "high, has an inside diameter of 91/4", and an outside diameter of 10".", "The cup thus sits 3"", "above the bottom of the tank.", "Both are made of glass.", "The virtual cathode hole is 2"", "in diameter.", "The workpiece is 4"", "in diameter and the extended anode is 6"", "in diameter so there is a 1"", "sacrificial edge around the workpiece.", "The cathode screen is 4"", "high and extends from the top of the tank.", "The anode is near the top of the tank.", "Changes and modifications in the specifically described embodiments can be carried out without departing from the scope of the invention which is intended to be limited only by the scope of the appended claims." ]
FIELD OF THE INVENTION The present invention relates to a fluorescence analytical apparatus for biochips fluorescence assay, and more specifically, a multiphoton excitation microscope which is applied to simultaneously excite several different fluorescence materials for effectively increasing the analytical efficiency. BACKGROUND OF THE INVENTION With the sequencing of human gene maps now on the verge of completion, the next challenge facing scientists is to understand the meanings and relationships among the thousands of genes, and to research the functions of proteins. Biochip technology is a power methodology to address this problem by its ability to monitor protein expression efficiently. The main characteristics of the biochip technology are providing accurate and rapid analysis, using less samples and reagents than conventional biochemical techniques, and monitoring the protein expression profiles of multiple proteins from different samples in a single experiment simultaneously. Due to the above characteristics, the biochip technology has found wide applications in gene function research, new drug development, disease detection, and clone selection. Undoubtedly, biochip technology will be a key biotechnological research tool in the 21st century. The biochip is a micro instrument. Scientists use extremely accurate technology to sequentially spot minute quantities of specific biological materials on a tiny carrier, manufactured from paper, glass, silicon, or other materials, for performing various examinations of biological samples. Biochips are classified into DNA chips (also called gene chips), protein chips, and microfluidic chips, with the DNA chip being the most developed technology. The principle on which the DNA chip is based is the fabrication of a high density array of thousands of single stranded DNAs (also called probes) localized on biological materials (generally called “chips”) manufactured from glass, nylon, or other materials. Two main sources of single stranded DNAs exist, oligonucleotide and complementary DNA (cDNA). The oligonucleotide chip is mainly manufactured by Affymetrix co., using A′ T′ C′ G bases, which comprise DNA, to construct 20 to 25 bases of the oligonucleotide. The cDNA chip uses the extract known as cDNA, taken from patient samples or other organisms. Then different oligonucleotide or cDNA sequences are positioned onto the chip in an orderly array. To perform the gene expression analysis, the messenger RNA of the sample is extracted and reversely transcribed to cDNA. The cDNA sequences obtained are then labeled with fluorescent materials and hybridized with the probes on the chip. The fluorescent signals are received and recorded using fluorescence imaging techniques such as confocal microscope. From analyzing the fluorescence pattern, gene expression patterns of the samples can be monitored. One of the most widely applications of the biochip technology is the study of diseases. Since over 60% of diseases are related to gene defects or abnormalities, knowledge of gene expression and functions is helpful in comprehending the mechanism of a disease, and can lead to the development of preventive and therapeutic measures. Therefore, researchers use a complex procedure to obtain proteins or genes samples through blood drawing, separation, braking, extraction, selection and signal amplifying hoping to identify gene-based diseases. These genes or proteins are subsequently used as biological materials for fabrication onto the biochips which then act as tamplates in examinations and experiments. The hybridization of the reversely transcribed and fluorescently tagged cDNA's with the biochip is monitored by fluorescence imaging techniques. A commonly used imaging technique is confocal microscopy. In most confocal microscopes, single-photon excitation is used to excite the fluorescent molecules. While single-photon confocal microscopy has been successfully applied to biochip fluorescence assay, this technique also has its limitation. Specifically, the light source of the confocal microscope is only capable of exciting fluorescent molecules whose wavelength is spectrally closed to the fluorescent emission. As a result, fluorescence analysis using single-photon excitation in multi-colored biochip analysis is difficult to achieve because a single-photon exciting wavelength cannot simultaneously excite fluorescent species with different emission characteristics. As a result, biochip analysis of multiple samples cannot be easily achieved using confocal microscope. SUMMARY OF THE INVENTION The first purpose of this invention is providing a multiphoton excitation microscope for detecting the fluorescence materials on a biochip. The second purpose of this invention is providing a multiphoton excitation microscope for simultaneously detecting differently colored fluorescence materials on the biochip. The third purpose of this invention is providing a multiphoton excitation microscope with multiple detection channels to increase the speed and efficiency of performing biochip fluorescence assay. This invention provides a multiphoton excitation microscope to simultaneously excite differently colored fluorescence materials of the biochip for effectively increasing the analytical efficiency. The microscope includes a gene chip, a multiphoton excitation light source such as the titanium-sapphire laser system, a beam scanner, an objective, and a plurality of detection channels. The gene chip is fabricated with high density of thousands of single stranded DNA. After hybridizing the single stranded DNA probes with fluorescently tagged cDNA's from the samples, the hybridization can be monitored using the multiphoton fluorescence imaging technique. Output of the titanium-sapphire laser system is passed through the beam scanner, and focused to a light spot by the objective to scan and excite the fluorescent materials hybridized onto the gene chip. Finally, the spectrally specific fluorescence is collected by the microscope objective and simultaneously recorded using the multiple detection channels. BRIEF DESCRIPTION OF THE DRAWINGS The foregoing, and additional objectives, features and advantages of the present invention will become apparent following the description of preferred embodiments thereof, taken in conjunction with the accompanying drawings, in which: FIG. 1 is the Jablonski diagram illustrating the typical energy converting during the fluorescence generation; and FIG. 2 is a diagrammatic illustrating a multiphoton excitation microscope described in accordance with the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In order to solve all the disadvantages taken from single-photon excitation, this invention discloses a multiphoton excitation microscope applied to substitute the traditional single-photon confocal microscope for obviously increasing the efficiency of analyzing the biochip. The two-photon excitation is illustrated below to excite the fluorescence. Two-photon excitation refers to the simultaneous absorption of two photons with the frequencies v1 and v2 by the fluorescent molecule. Energetically, this process if equivalent to the molecular excitation by a photon with a frequency equal to the sum of v1 and v2. Because two photons are involved in two-photon excitation, the transition rate increases with the square of the incident photon flux. In addition, since the two-photon absorption cross-section is low, high instantaneous power is needed to ensure efficient excitation. The emitting fluorescence originats from the electron transition of an atom or a molecule. FIG. 1 illustrates the Jablonski diagram used to demonstrate the energy level transition resulting in fluorescence generation. In this diagram, S0 represents the ground singlet state, and the S1 and S2 represent the first and the second excited singlet states of electrons, respectively. In the case that no photon is absorbed, the Boltzmann distribution measuring the relative population of the excited to the ground state molecules can be expressed as the following: R=e −ΔE/KT where ΔE indicates the energy gap between band levels, K represents the Boltzmann constant, and T is the absolute temperature. At room temperature, most molecules are at the ground state. As a result, little fluorescence emission is observed. However, when a photon with specific wavelength is absorbed by object molecules, the molecules are excited to higher energy levels represented by S1 (arrow 2) and S2 (arrow 1). Generally speaking, the molecules at the S2 energy level will quickly decay to the S1 (arrow 3) energy level by non-radiative transition. Subsequently, the molecules at the S1 energy level decay to the S0 (arrow 4) energy level and produce fluorescence in the process. Typically, fluorescence emission occurs on the time scale of around 10 nanoseconds. Notedly, the excited fluorescence can also be taken from two-photon or multiphoton excitation. FIG. 2 discloses a multiphoton excitation microscope 120 for simultaneously exciting differently colored fluorescence materials on a biochip to effectively increase the analysis efficiency. First the biochip 10 is spotted high density of thousands of single stranded DNAs 20 (also called probes). The material of the biochip can be chosen from glass, nylon, or other materials. The source of the single stranded DNAs can be chosen from oligonucleotides or complementary DNAs (cDNAs). The single stranded DNAs can also be selected from proteins, antigens, or antibodies based on the experiments needs. Next, the messenger RNAs of samples are extracted, and reversely transcribed to cDNAs. The cDNAs are labeled with fluorescence materials prior to biochip 10 hybridization with the probes 20 (single stranded DNAs). After hybridizing of the probes 20 with the labeled cDNAs, the biochip 10 has bound fluorescence. The fluorescence is the hybridized biological signals, and is examined by a multiphoton excitation microscope. A multiphoton excitation source 30 of the multiphoton excitation microscope can generate exciting light for simultaneously exciting differently colored fluorescence materials on the biochip 10 . In one preferred embodiment, titanium-sapphire laser system is chosen to excite the near-infrared light whose wavelength is between 700 nm to 1000 nm. When the exciting light is emitted from the multiphoton excitation source 30 , it is reflected in sequence by the first mirror 80 and the source 30 , it is reflected in sequence by the first mirror 80 and the second mirror 90 and is transmitted to a beam scanner 40 . Then the light delivered from the beam scanner is amplified and paralleled by a beam mirror means 100 . Subsequently the light beam is focused to a light spot by an objective 50 to excite the fluorescence bound on the biochip 10 . Note that the fluorescence (the hybridized biological signals) of the biochip 10 can be scanned one by one with this light beam according to the beam scanner setting. Then the excited fluorescence having characteristic wavelengths is received by the objective 50 . After that, the fluorescence is separated by a dichroic mirror 110 into the different detection channels. The passed fluorescence can be filtered individually by using multiple filters 60 , following detecting the fluorescence by the respective detection channels 70 . In the preferred embodiment, four sets of filters and detection channels are applied to detect the fluorescence, and the filters can also be chosen from prisms or gratings. At last, the biological signals carried by the fluorescence are transmitted to a computer for data analysis. There are a number of advantages in examining the biological signals on the biochip using multiphoton excitation microscope: (1) Because the differences of the excited wavelengths between multiphoton and emitting fluorescence are considerable large, the intact emitting spectrum can be easily obtained. (2) In addition, the differently colored fluorescence materials can be excited simultaneously by the multiphoton excitation microscope, so multi-color fluorescence analysis of the biochip can be examined simultaneously. These make the applications of the multiphoton excitation microscope more variable, increase the analytical efficiency and decrease the biochip consumption to prevent the high cost; (3) To confine specimen photodamage to the vicinity of the focal “point.” While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.
A multiphoton excitaion microscope for simultaneously detecting differently colored fluorescence materials on biochips includes a multiphoton excitation source, objectives, and a plurality of detection channels. The biochip is hybridized and labeled with fluorescence materials for expressing hybridized biological signals. The multiphoton excitation source is focused to a light spot on the biochip to excite the fluorescence materials bound thereon. After that, the fluorescence emission at different wavelengths from the different fluorescent materials can be detected by the plural detection channels.
Summarize the key points of the given document.
[ "FIELD OF THE INVENTION The present invention relates to a fluorescence analytical apparatus for biochips fluorescence assay, and more specifically, a multiphoton excitation microscope which is applied to simultaneously excite several different fluorescence materials for effectively increasing the analytical efficiency.", "BACKGROUND OF THE INVENTION With the sequencing of human gene maps now on the verge of completion, the next challenge facing scientists is to understand the meanings and relationships among the thousands of genes, and to research the functions of proteins.", "Biochip technology is a power methodology to address this problem by its ability to monitor protein expression efficiently.", "The main characteristics of the biochip technology are providing accurate and rapid analysis, using less samples and reagents than conventional biochemical techniques, and monitoring the protein expression profiles of multiple proteins from different samples in a single experiment simultaneously.", "Due to the above characteristics, the biochip technology has found wide applications in gene function research, new drug development, disease detection, and clone selection.", "Undoubtedly, biochip technology will be a key biotechnological research tool in the 21st century.", "The biochip is a micro instrument.", "Scientists use extremely accurate technology to sequentially spot minute quantities of specific biological materials on a tiny carrier, manufactured from paper, glass, silicon, or other materials, for performing various examinations of biological samples.", "Biochips are classified into DNA chips (also called gene chips), protein chips, and microfluidic chips, with the DNA chip being the most developed technology.", "The principle on which the DNA chip is based is the fabrication of a high density array of thousands of single stranded DNAs (also called probes) localized on biological materials (generally called “chips”) manufactured from glass, nylon, or other materials.", "Two main sources of single stranded DNAs exist, oligonucleotide and complementary DNA (cDNA).", "The oligonucleotide chip is mainly manufactured by Affymetrix co.", ", using A′ T′ C′ G bases, which comprise DNA, to construct 20 to 25 bases of the oligonucleotide.", "The cDNA chip uses the extract known as cDNA, taken from patient samples or other organisms.", "Then different oligonucleotide or cDNA sequences are positioned onto the chip in an orderly array.", "To perform the gene expression analysis, the messenger RNA of the sample is extracted and reversely transcribed to cDNA.", "The cDNA sequences obtained are then labeled with fluorescent materials and hybridized with the probes on the chip.", "The fluorescent signals are received and recorded using fluorescence imaging techniques such as confocal microscope.", "From analyzing the fluorescence pattern, gene expression patterns of the samples can be monitored.", "One of the most widely applications of the biochip technology is the study of diseases.", "Since over 60% of diseases are related to gene defects or abnormalities, knowledge of gene expression and functions is helpful in comprehending the mechanism of a disease, and can lead to the development of preventive and therapeutic measures.", "Therefore, researchers use a complex procedure to obtain proteins or genes samples through blood drawing, separation, braking, extraction, selection and signal amplifying hoping to identify gene-based diseases.", "These genes or proteins are subsequently used as biological materials for fabrication onto the biochips which then act as tamplates in examinations and experiments.", "The hybridization of the reversely transcribed and fluorescently tagged cDNA's with the biochip is monitored by fluorescence imaging techniques.", "A commonly used imaging technique is confocal microscopy.", "In most confocal microscopes, single-photon excitation is used to excite the fluorescent molecules.", "While single-photon confocal microscopy has been successfully applied to biochip fluorescence assay, this technique also has its limitation.", "Specifically, the light source of the confocal microscope is only capable of exciting fluorescent molecules whose wavelength is spectrally closed to the fluorescent emission.", "As a result, fluorescence analysis using single-photon excitation in multi-colored biochip analysis is difficult to achieve because a single-photon exciting wavelength cannot simultaneously excite fluorescent species with different emission characteristics.", "As a result, biochip analysis of multiple samples cannot be easily achieved using confocal microscope.", "SUMMARY OF THE INVENTION The first purpose of this invention is providing a multiphoton excitation microscope for detecting the fluorescence materials on a biochip.", "The second purpose of this invention is providing a multiphoton excitation microscope for simultaneously detecting differently colored fluorescence materials on the biochip.", "The third purpose of this invention is providing a multiphoton excitation microscope with multiple detection channels to increase the speed and efficiency of performing biochip fluorescence assay.", "This invention provides a multiphoton excitation microscope to simultaneously excite differently colored fluorescence materials of the biochip for effectively increasing the analytical efficiency.", "The microscope includes a gene chip, a multiphoton excitation light source such as the titanium-sapphire laser system, a beam scanner, an objective, and a plurality of detection channels.", "The gene chip is fabricated with high density of thousands of single stranded DNA.", "After hybridizing the single stranded DNA probes with fluorescently tagged cDNA's from the samples, the hybridization can be monitored using the multiphoton fluorescence imaging technique.", "Output of the titanium-sapphire laser system is passed through the beam scanner, and focused to a light spot by the objective to scan and excite the fluorescent materials hybridized onto the gene chip.", "Finally, the spectrally specific fluorescence is collected by the microscope objective and simultaneously recorded using the multiple detection channels.", "BRIEF DESCRIPTION OF THE DRAWINGS The foregoing, and additional objectives, features and advantages of the present invention will become apparent following the description of preferred embodiments thereof, taken in conjunction with the accompanying drawings, in which: FIG. 1 is the Jablonski diagram illustrating the typical energy converting during the fluorescence generation;", "and FIG. 2 is a diagrammatic illustrating a multiphoton excitation microscope described in accordance with the present invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In order to solve all the disadvantages taken from single-photon excitation, this invention discloses a multiphoton excitation microscope applied to substitute the traditional single-photon confocal microscope for obviously increasing the efficiency of analyzing the biochip.", "The two-photon excitation is illustrated below to excite the fluorescence.", "Two-photon excitation refers to the simultaneous absorption of two photons with the frequencies v1 and v2 by the fluorescent molecule.", "Energetically, this process if equivalent to the molecular excitation by a photon with a frequency equal to the sum of v1 and v2.", "Because two photons are involved in two-photon excitation, the transition rate increases with the square of the incident photon flux.", "In addition, since the two-photon absorption cross-section is low, high instantaneous power is needed to ensure efficient excitation.", "The emitting fluorescence originats from the electron transition of an atom or a molecule.", "FIG. 1 illustrates the Jablonski diagram used to demonstrate the energy level transition resulting in fluorescence generation.", "In this diagram, S0 represents the ground singlet state, and the S1 and S2 represent the first and the second excited singlet states of electrons, respectively.", "In the case that no photon is absorbed, the Boltzmann distribution measuring the relative population of the excited to the ground state molecules can be expressed as the following: R=e −ΔE/KT where ΔE indicates the energy gap between band levels, K represents the Boltzmann constant, and T is the absolute temperature.", "At room temperature, most molecules are at the ground state.", "As a result, little fluorescence emission is observed.", "However, when a photon with specific wavelength is absorbed by object molecules, the molecules are excited to higher energy levels represented by S1 (arrow 2) and S2 (arrow 1).", "Generally speaking, the molecules at the S2 energy level will quickly decay to the S1 (arrow 3) energy level by non-radiative transition.", "Subsequently, the molecules at the S1 energy level decay to the S0 (arrow 4) energy level and produce fluorescence in the process.", "Typically, fluorescence emission occurs on the time scale of around 10 nanoseconds.", "Notedly, the excited fluorescence can also be taken from two-photon or multiphoton excitation.", "FIG. 2 discloses a multiphoton excitation microscope 120 for simultaneously exciting differently colored fluorescence materials on a biochip to effectively increase the analysis efficiency.", "First the biochip 10 is spotted high density of thousands of single stranded DNAs 20 (also called probes).", "The material of the biochip can be chosen from glass, nylon, or other materials.", "The source of the single stranded DNAs can be chosen from oligonucleotides or complementary DNAs (cDNAs).", "The single stranded DNAs can also be selected from proteins, antigens, or antibodies based on the experiments needs.", "Next, the messenger RNAs of samples are extracted, and reversely transcribed to cDNAs.", "The cDNAs are labeled with fluorescence materials prior to biochip 10 hybridization with the probes 20 (single stranded DNAs).", "After hybridizing of the probes 20 with the labeled cDNAs, the biochip 10 has bound fluorescence.", "The fluorescence is the hybridized biological signals, and is examined by a multiphoton excitation microscope.", "A multiphoton excitation source 30 of the multiphoton excitation microscope can generate exciting light for simultaneously exciting differently colored fluorescence materials on the biochip 10 .", "In one preferred embodiment, titanium-sapphire laser system is chosen to excite the near-infrared light whose wavelength is between 700 nm to 1000 nm.", "When the exciting light is emitted from the multiphoton excitation source 30 , it is reflected in sequence by the first mirror 80 and the source 30 , it is reflected in sequence by the first mirror 80 and the second mirror 90 and is transmitted to a beam scanner 40 .", "Then the light delivered from the beam scanner is amplified and paralleled by a beam mirror means 100 .", "Subsequently the light beam is focused to a light spot by an objective 50 to excite the fluorescence bound on the biochip 10 .", "Note that the fluorescence (the hybridized biological signals) of the biochip 10 can be scanned one by one with this light beam according to the beam scanner setting.", "Then the excited fluorescence having characteristic wavelengths is received by the objective 50 .", "After that, the fluorescence is separated by a dichroic mirror 110 into the different detection channels.", "The passed fluorescence can be filtered individually by using multiple filters 60 , following detecting the fluorescence by the respective detection channels 70 .", "In the preferred embodiment, four sets of filters and detection channels are applied to detect the fluorescence, and the filters can also be chosen from prisms or gratings.", "At last, the biological signals carried by the fluorescence are transmitted to a computer for data analysis.", "There are a number of advantages in examining the biological signals on the biochip using multiphoton excitation microscope: (1) Because the differences of the excited wavelengths between multiphoton and emitting fluorescence are considerable large, the intact emitting spectrum can be easily obtained.", "(2) In addition, the differently colored fluorescence materials can be excited simultaneously by the multiphoton excitation microscope, so multi-color fluorescence analysis of the biochip can be examined simultaneously.", "These make the applications of the multiphoton excitation microscope more variable, increase the analytical efficiency and decrease the biochip consumption to prevent the high cost;", "(3) To confine specimen photodamage to the vicinity of the focal “point.”", "While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention." ]
BACKGROUND OF THE INVENTION The present application is a continuation-in-part application of my copending U.S. patent application bearing the same title and filed Aug. 24, 1977 under Ser. No. 827,355 now abandoned. The present invention concerns generally rod holders affixable to the gunwale of a boat. The use of rod holders is commonplace to relieve the person fishing of the tiring task of holding the rod. Most such rod holders provide for the convenient release of the rod to enable playing of the fish in the usual manner. SUMMARY OF THE PRESENT INVENTION The present invention is embodied within a rod holder adjustably attachable to the gunwale of a boat and permits both convenient insertion and release of a fishing rod handle while positively retaining same against inadvertent release. The present rod holder is embodied within a cylindrical casing within which is rotatably mounted a cylinder shaped to receive various types of fishing rod handles associated with open face and closed face spinning reels as well as a bait casting reel to provide a highly adaptable fishing rod holder. The rod receptacle, as briefly described above, is supported by a curved support member with a clamping assembly positionable and locable along the curved support member to enable positioning of the rod at the desired inclination. Further, the clamping assembly additionally enables rod receptacle movement about an upright axis to permit the user to move the rod in a limited manner for purposes of determining whether or not a fish has been hooked. Other objects of the invention will be obvious from an understanding of the following description. BRIEF DESCRIPTION OF THE DRAWING In the accompanying drawing: FIG. 1 is a fragmentary view in side elevation showing essential parts of a fishing rod and a boat side, together with means for adjustably and operatively holding a fishing rod and line on a side of the boat; FIG. 2 is a fragmentary plan view of the structure shown in FIG. 1, but with the parts readjusted to a condition in which the rod and line can be withdrawn from the holder; FIG. 3 is a view similar to FIG. 2 but with the rod and line carrying means swung to an operative position; FIG. 4 is a view in sectional elevation, the section being taken along the line 4--4 of FIG. 2, looking in the direction of the arrows; FIG. 5 is a view in sectional elevation, the section being taken along line 5--5 of FIG. 3, looking in the direction of the arrows; FIG. 6 is a side elevational view of a modified form of rod holder for open face spinning reels; FIG. 7 is an end elevational view taken along line 7--7 of FIG. 6; FIG. 8 is a vertical sectional view taken along line 8--8 of FIG. 6; FIG. 9 is a sectional view taken downwardly along line 9--9 of FIG. 6; FIG. 10 is a side elevational view of still another modified form of the rod holder; FIG. 11 is a plan view of the rod holder receptacle of FIG. 10 with the rod handle and reel removed; and FIG. 12 is a sectional view of the rod receptacle taken along line 12--12 of FIG. 11. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As seen in FIG. 1 a boat side 10 terminates in a gunwale 12 to which a semi-circular clamping member 14 is detachably affixed by a thumb screw 16. The member 14 is formed with a circular opening through which the shank of the screw 16 passes. When the screw 16 is turned clockwise it presses a washer 18 firmly against the gunwale 12 and thereby clamps the member firmly to a boat side. The member 14 has a circumferentially extending groove indicated by the broken line 20. When the thumb screw 16 is turned firmly home, the member 14 is held fixedly in place. The fishing line and rod carrier 22 includes an elongated longitudinally slotted, bracket 24 which is adjustably connected to the member 14 through a screw 26, a pair of clamping washers 28--28 and a wing nut 30. The bracket 24 has inturned ends affixed to partial metallic sleeves 32. The partial metallic sleeves 32 extend around end portions of a partial metallic sleeve 33. The sleeve 33 has a gap, about sixty degrees in width, which extends for its full length. Two additional gaps, each about sixty degrees in length and about an inch across are spaced inwardly equally from opposite ends of the sleeve. A generally substantially identical plastic sleeve 34 of slightly smaller diameter serves as a spacer and fits fixedly within the sleeve 33 and is restrained against rotation by outturned flange portions 36 and 38. Within the fixed sleeve member 34 a partial sleeve 40 of plastic is revolvubly mounted, the sleeve 40 being free to turn within and relative to the sleeve member 34. The fishing rod 42 may be of conventional construction. As illustrated it comprises a rod portion 44 and a handle portion 46. The handle portion 46 carries a stem 48 on which a conventional reel 50 and reel operating handle 52 are mounted. The plastic sleeve 40 has affixed to its inner surface at its opposite ends rod holding springs 41. When it is desired to install the pole and associated structures in the mount, the inner sleeve is adjusted to align its slot with the long slot of the outer sleeve, the rod is inserted to align the stem 48 with a slot 54, and is turned into the slot. The rod may be reversed end for end relative to the holder. In FIGS. 6 through 9 I show a modified form of the rod holder which, as before, is mounted to a gunwale 55 of a boat. A semi-circular support member 56 defines a lengthwise extending slot 56A. A straight segment 57 of the clamping member slidably engages a base 58 flanged along its sides at 58A. A locking screw is threadedly engaged with said straight segment of the bracket and upon advancement serves to lock support member 56 by biasing its straight segment outwardly against flanges 58A. Base 58 may be permanently affixed to the boat by suitable fasteners. Disposed for arcuate sliding travel on semi-circular support member 56 is a clamp assembly generally at 61 and including a screw 62 projecting upwardly through a flanged fitting 63 the flanges of which bear upon the support member. A friction washer at 64 is disposed intermediate said fitting and washer 65 the latter having upturned ears or projections 65A. Supported by said ears are washers 66 and 67 while a wing nut 68 on screw 62 secures the clamp assembly to the semi-circular support member 56. Washer 66 has opposed chordal edges 66A-66B as seen in FIG. 9. A rod receptacle is indicated generally at 70 and includes a cylindrical casing 71 partially closed at its ends by plates 72. Within casing 71 is a bifurcated cylinder 73 defining a lengthwise open area 73A for reception of a rod handle 74 of a rod 75 of the type usable with an open face spinning reel 76. Bifurcated cylinder 73 is freely rotatably within casing 71 to communicate its open area 73A with a lengthwise extending open area 71A in the casing to permit lateral extraction and insertion of the rod handle. A transverse arcuate opening 71B in the casing receives the stem 77 of the spinning reel. A bracket 78 on the casing is swingably received between eared washer 65 and superjacent chordal washer 66 by reason of washer ears 65A preventing clamping of the intermediate bracket portion. Accordingly bracket 78 may pivot about the axis of screw 62 until contact with an ear 65A to permit the fisherman to periodically "test" the action of a trolled lure or determine if a fish has been hooked. If so desired, eared washer 65 may be repositioned ninety degrees to locate its ears for insertion into bracket openings 78A (FIG. 9) in which instance the chordal sides 66A-66B of washer 66 may slide therepast permitting washer abutment against the bracket to hold same against rotation. In FIGS. 10, 11 and 12 I show a further modified form of the invention which includes a different rod receptacle but retaining the same type of support member, indicated 56', and a clamping assembly at 61' as that illustrated in FIGS. 6 through 9. The rod receptacle, generally at 80, includes a cylindrical casing 81 having open areas 82 and 83 adjacent each end thereof and a central open area 81A through which the handle 84 of a rod 85 may laterally pass during insertion and removal. Rod 85 is the type for use with a closed face spinning reel 86. The enlarged central open area 81A is also for reception of reel 86. An arcuate casing opening at 90 receives the fingergrip 91 of the rod handle and extends arcuately about ninety degrees to permit fingergrip rotation. Slots 92 and 93 adjacent each casing end receive limit stops 94 to limit rotational movement and prevent axial movement of a cylinder, later described, within said casing. An arcuate opening at 96 optionally receives the fingergrip of an inverted bait casting rod (not shown) upon the casing 81 being turned end-for-end. A cylinder 95 is rotatably confined within the casing and is of hollow construction having open areas 96-97 corresponding generally with casing open areas 82-83, and which are partially closed by end blocks 98-99 which have aligned recesses 98A-99A therein which receive and support the inserted rod handle. A cylinder opening 100 receives the fingergrip 91 of the rod handle. With the casing open areas in register with the cylinder open areas, as shown in FIG. 12, the rod handle may be lowered into placement within the cylinder with handle segments resting on the cylinder end blocks 98-99. With attention to FIG. 11 it will be seen that counterclockwise rotation of the cylinder will cause the cylinder open areas 95A, 96 and 97 to be closed by the casing to thereby confine the rod handle against dislodgement. Rod handle release in the event of a strike entails only partial rotation of cylinder 95 by rotation of the rod handle whereupon the handle may be lifted free of the holder. The other features of the clamping assembly are, as aforesaid, associated with this form of the invention. While I have shown but a few embodiments of the invention it will be apparent to those skilled in the art that the invention may be embodied still otherwise without departing from the spirit and scope of the invention. Having thus described the invention, what is desired to be secured under a Letters Patent is:
A fishing rod holder including a rod receptacle having a casing within which is rotatably mounted a cylinder both having lengthwise openings to receive a laterally inserted rod handle. The cylinder opening is closed by the casing upon cylinder rotation. A clamping assembly carries the casing and is positionable along a curved support member to vary rod inclination. The clamping assembly permits fore and aft movement of the rod tip to determine if a fish is on.
Briefly summarize the invention's components and working principles as described in the document.
[ "BACKGROUND OF THE INVENTION The present application is a continuation-in-part application of my copending U.S. patent application bearing the same title and filed Aug. 24, 1977 under Ser.", "No. 827,355 now abandoned.", "The present invention concerns generally rod holders affixable to the gunwale of a boat.", "The use of rod holders is commonplace to relieve the person fishing of the tiring task of holding the rod.", "Most such rod holders provide for the convenient release of the rod to enable playing of the fish in the usual manner.", "SUMMARY OF THE PRESENT INVENTION The present invention is embodied within a rod holder adjustably attachable to the gunwale of a boat and permits both convenient insertion and release of a fishing rod handle while positively retaining same against inadvertent release.", "The present rod holder is embodied within a cylindrical casing within which is rotatably mounted a cylinder shaped to receive various types of fishing rod handles associated with open face and closed face spinning reels as well as a bait casting reel to provide a highly adaptable fishing rod holder.", "The rod receptacle, as briefly described above, is supported by a curved support member with a clamping assembly positionable and locable along the curved support member to enable positioning of the rod at the desired inclination.", "Further, the clamping assembly additionally enables rod receptacle movement about an upright axis to permit the user to move the rod in a limited manner for purposes of determining whether or not a fish has been hooked.", "Other objects of the invention will be obvious from an understanding of the following description.", "BRIEF DESCRIPTION OF THE DRAWING In the accompanying drawing: FIG. 1 is a fragmentary view in side elevation showing essential parts of a fishing rod and a boat side, together with means for adjustably and operatively holding a fishing rod and line on a side of the boat;", "FIG. 2 is a fragmentary plan view of the structure shown in FIG. 1, but with the parts readjusted to a condition in which the rod and line can be withdrawn from the holder;", "FIG. 3 is a view similar to FIG. 2 but with the rod and line carrying means swung to an operative position;", "FIG. 4 is a view in sectional elevation, the section being taken along the line 4--4 of FIG. 2, looking in the direction of the arrows;", "FIG. 5 is a view in sectional elevation, the section being taken along line 5--5 of FIG. 3, looking in the direction of the arrows;", "FIG. 6 is a side elevational view of a modified form of rod holder for open face spinning reels;", "FIG. 7 is an end elevational view taken along line 7--7 of FIG. 6;", "FIG. 8 is a vertical sectional view taken along line 8--8 of FIG. 6;", "FIG. 9 is a sectional view taken downwardly along line 9--9 of FIG. 6;", "FIG. 10 is a side elevational view of still another modified form of the rod holder;", "FIG. 11 is a plan view of the rod holder receptacle of FIG. 10 with the rod handle and reel removed;", "and FIG. 12 is a sectional view of the rod receptacle taken along line 12--12 of FIG. 11.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As seen in FIG. 1 a boat side 10 terminates in a gunwale 12 to which a semi-circular clamping member 14 is detachably affixed by a thumb screw 16.", "The member 14 is formed with a circular opening through which the shank of the screw 16 passes.", "When the screw 16 is turned clockwise it presses a washer 18 firmly against the gunwale 12 and thereby clamps the member firmly to a boat side.", "The member 14 has a circumferentially extending groove indicated by the broken line 20.", "When the thumb screw 16 is turned firmly home, the member 14 is held fixedly in place.", "The fishing line and rod carrier 22 includes an elongated longitudinally slotted, bracket 24 which is adjustably connected to the member 14 through a screw 26, a pair of clamping washers 28--28 and a wing nut 30.", "The bracket 24 has inturned ends affixed to partial metallic sleeves 32.", "The partial metallic sleeves 32 extend around end portions of a partial metallic sleeve 33.", "The sleeve 33 has a gap, about sixty degrees in width, which extends for its full length.", "Two additional gaps, each about sixty degrees in length and about an inch across are spaced inwardly equally from opposite ends of the sleeve.", "A generally substantially identical plastic sleeve 34 of slightly smaller diameter serves as a spacer and fits fixedly within the sleeve 33 and is restrained against rotation by outturned flange portions 36 and 38.", "Within the fixed sleeve member 34 a partial sleeve 40 of plastic is revolvubly mounted, the sleeve 40 being free to turn within and relative to the sleeve member 34.", "The fishing rod 42 may be of conventional construction.", "As illustrated it comprises a rod portion 44 and a handle portion 46.", "The handle portion 46 carries a stem 48 on which a conventional reel 50 and reel operating handle 52 are mounted.", "The plastic sleeve 40 has affixed to its inner surface at its opposite ends rod holding springs 41.", "When it is desired to install the pole and associated structures in the mount, the inner sleeve is adjusted to align its slot with the long slot of the outer sleeve, the rod is inserted to align the stem 48 with a slot 54, and is turned into the slot.", "The rod may be reversed end for end relative to the holder.", "In FIGS. 6 through 9 I show a modified form of the rod holder which, as before, is mounted to a gunwale 55 of a boat.", "A semi-circular support member 56 defines a lengthwise extending slot 56A.", "A straight segment 57 of the clamping member slidably engages a base 58 flanged along its sides at 58A.", "A locking screw is threadedly engaged with said straight segment of the bracket and upon advancement serves to lock support member 56 by biasing its straight segment outwardly against flanges 58A.", "Base 58 may be permanently affixed to the boat by suitable fasteners.", "Disposed for arcuate sliding travel on semi-circular support member 56 is a clamp assembly generally at 61 and including a screw 62 projecting upwardly through a flanged fitting 63 the flanges of which bear upon the support member.", "A friction washer at 64 is disposed intermediate said fitting and washer 65 the latter having upturned ears or projections 65A.", "Supported by said ears are washers 66 and 67 while a wing nut 68 on screw 62 secures the clamp assembly to the semi-circular support member 56.", "Washer 66 has opposed chordal edges 66A-66B as seen in FIG. 9. A rod receptacle is indicated generally at 70 and includes a cylindrical casing 71 partially closed at its ends by plates 72.", "Within casing 71 is a bifurcated cylinder 73 defining a lengthwise open area 73A for reception of a rod handle 74 of a rod 75 of the type usable with an open face spinning reel 76.", "Bifurcated cylinder 73 is freely rotatably within casing 71 to communicate its open area 73A with a lengthwise extending open area 71A in the casing to permit lateral extraction and insertion of the rod handle.", "A transverse arcuate opening 71B in the casing receives the stem 77 of the spinning reel.", "A bracket 78 on the casing is swingably received between eared washer 65 and superjacent chordal washer 66 by reason of washer ears 65A preventing clamping of the intermediate bracket portion.", "Accordingly bracket 78 may pivot about the axis of screw 62 until contact with an ear 65A to permit the fisherman to periodically "test"", "the action of a trolled lure or determine if a fish has been hooked.", "If so desired, eared washer 65 may be repositioned ninety degrees to locate its ears for insertion into bracket openings 78A (FIG.", "9) in which instance the chordal sides 66A-66B of washer 66 may slide therepast permitting washer abutment against the bracket to hold same against rotation.", "In FIGS. 10, 11 and 12 I show a further modified form of the invention which includes a different rod receptacle but retaining the same type of support member, indicated 56', and a clamping assembly at 61'", "as that illustrated in FIGS. 6 through 9.", "The rod receptacle, generally at 80, includes a cylindrical casing 81 having open areas 82 and 83 adjacent each end thereof and a central open area 81A through which the handle 84 of a rod 85 may laterally pass during insertion and removal.", "Rod 85 is the type for use with a closed face spinning reel 86.", "The enlarged central open area 81A is also for reception of reel 86.", "An arcuate casing opening at 90 receives the fingergrip 91 of the rod handle and extends arcuately about ninety degrees to permit fingergrip rotation.", "Slots 92 and 93 adjacent each casing end receive limit stops 94 to limit rotational movement and prevent axial movement of a cylinder, later described, within said casing.", "An arcuate opening at 96 optionally receives the fingergrip of an inverted bait casting rod (not shown) upon the casing 81 being turned end-for-end.", "A cylinder 95 is rotatably confined within the casing and is of hollow construction having open areas 96-97 corresponding generally with casing open areas 82-83, and which are partially closed by end blocks 98-99 which have aligned recesses 98A-99A therein which receive and support the inserted rod handle.", "A cylinder opening 100 receives the fingergrip 91 of the rod handle.", "With the casing open areas in register with the cylinder open areas, as shown in FIG. 12, the rod handle may be lowered into placement within the cylinder with handle segments resting on the cylinder end blocks 98-99.", "With attention to FIG. 11 it will be seen that counterclockwise rotation of the cylinder will cause the cylinder open areas 95A, 96 and 97 to be closed by the casing to thereby confine the rod handle against dislodgement.", "Rod handle release in the event of a strike entails only partial rotation of cylinder 95 by rotation of the rod handle whereupon the handle may be lifted free of the holder.", "The other features of the clamping assembly are, as aforesaid, associated with this form of the invention.", "While I have shown but a few embodiments of the invention it will be apparent to those skilled in the art that the invention may be embodied still otherwise without departing from the spirit and scope of the invention.", "Having thus described the invention, what is desired to be secured under a Letters Patent is:" ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to beverage containers and more particularly to a disposable non-spillable beverage container having the traditional cup-like frustoconical form and a container bottom where the bottom consists of a, second, smaller inverted capped conical frustum, emanating from the base of the container, where the frustum serves as an integral element of a special straw and as a fastening element. The invention also relates to accoutering components that enhance the utility of the beverage container; more particularly a special straw, a lid, and various fastening devices for securing the beverage container. 2. Description of the Prior Art The prior art has a number of patents that read on cup-like beverage containers where the cup has been modified to be inclusive of an integral straw. Leeds' 3,558,033 discloses a cup with a built in telescoping drinking straw secured to the inside surface of the cup. H. J. Drown discloses in his patent 2,948,453 a nonspillable liquid drinking container comprised of a cup, a lid, and a bendable straw that penetrates through an aperture in the lid. U.S. Pat. No. 4,573,631 reads on a beverage container having an integral straw, lid, cup combination. The straw and the lid are incorporated into the body of the cup itself. SUMMARY OF THE INVENTION The beverage container of the present invention includes a substantially frustoconically shaped external body member terminating in a rim at the upper extremity and a base at the lower extremity, where the base is contiguous with an internal body member that is substantially a second, smaller inverted, conical hollow core frustum terminating in an apical closure at the upper extremity and a joining flange at the lower extremity, where the flange integrally joins the internal body member with the base of the external body member, therein forming a bifrustoconical beverage container. The frustum of the internal body member emanates centrally, coaxially and upwardly from the base, the combination of the capped frustum and the flange of the internal body member therein forming the bottom of the container. The height of the frustum of the internal body member is, preferably, such that no more than half of the total volume of the total bifrustoconical container is located in the spatial region of the container defined by points consisting of a horizontal plane drawn through the external body member at the apices of the internal body member, the perimeter of the external body member, and a horizontal plane drawn through the rim of the external body member. An object of this preferred height of the frustum of the internal body member is to structure the geometry of the container such that when the container is filled, the center of gravity of the container is below the apex of the internal body member. A second object of the present invention is that the container can be secured by inserting, through the open ended hollow core frustoconical bottom of the container, a mounted vertical fastening element, for instance a mounted pintle or peg. The slanted walls of the conical frustum guide the insertion centrally, therein facilitating alignment of the container into a fixed position. Also, if the vertical fastening element is of sufficient length to contact the underside of the apex and the vertical fastening element has a radial thickness smaller than the smaller radius of the frustum, then the beverage container, resting on the vertical element, will be self righting through a maximum angle of deflection functionally dependent on the angle of the walls of the frustum from its axis. The underside of the apex will serve as the pivot point, and the top of the vertical fastening element will serve as the fulcrum. The bifrustoconical beverage container is composed of a malleable material, preferably a resilient plastic material. The preferred method of manufacture is a molding process using an extrudable plastic material. It is anticipated that molding processes are amenable to making very complex shapes, and that variations on the basic bifrustoconical design can and will be adopted. For instance, the external body member could be a combination of an octabedral frustum and a conical frustum; and the internal body member could be Gaussian in shape. A third object of the present invention is that the beverage container has substantially a bifrustoconical shape, and the invention is inclusive of variations on this general design. The beverage container of the present invention includes a closing lid which fastens to the rim of the external body member. The epicenter of the lid has a closed straw passage and opening means, where the passage is of sufficient size to allow an inserted straw to snugly pass through the resulting aperture when the passage is opened. The passage is normally closed, unless a straw is about to be or has been inserted into the passage. The beverage container of the present invention includes a novel multi-sectional straw, being comprised of an upper essentially linear tubular section, a lower essentially conical frustum section, and an intermediate expander section which integrally joins the upper tubular section to the lower conical frustum section, and in particular the smaller circular end of the lower conical frustum section. The uppermost end of the tubular section of the straw is the exit, and, therefore is open ended, being the point of fluid conveyance to the drinker; and the periphery of the lowermost end of the conical section of the straw is the entrance. The conical section of the multisectional straw is sized so that the interior wall of the conical section will fit superimposed over substantially the entire length of the frustum of the internal body member, therein forming a thin annular chamber in between the straw and the frustum of the internal body member. Furthermore, the conical section of the straw is preferably sized such that the thin annular chamber has a horizontal cross-sectional area that is nearly invariant as to the height on the superimposed frustums, and that this cross-sectional area is roughly equal to the cross-sectional area of the tubular section of the straw. The conical section of the straw is positioned such that fluid can communicate from the lower most bottom of the container, through the straw entrance and into the thin annular chamber. Positioning can be affected through the use of tabs at the entrance of the straw, flutes or small protuberances on the interior walls of the conical section of the straw or any other suitable means. The intermediate expander section of the straw serves to expand the diameter of the tubular section of the straw up to the diameter of the conical frustum section of the straw, and through this transition, the expander section closely follows the exterior contour of the apices of the internal body member. As a functioning straw, fluid is drawn in radially through the periphery of the straw entrance into the thin annular chamber, upward in the superimposed frustums, into the intermediate expander section and into the tubular section of the straw. The drinker when consuming a very viscous beverage such as a milk shake has the option of increasing the effective diameter of the conical frustum section of the straw by simply lifting the straw upwards out of the container slightly, which increases the size of the thin annular chamber, therein making it easier to suck the contents through the straw into the drinker's mouth. The conical frustum section of the straw also tends to align stringy consumables like noodles, and certain soups can be eaten using this multi-sectional straw that will not pass through an conventional straw. An object of the present invention is that the tubular section of the multi-sectional straw has corrugated ribbing that imparts flexibility to the tubular section. The corrugation allow the tubular section of the straw to be bent, without crimping, therein enabling the straw to be adjusted to an angle more suitable for consumption without tilting the beverage container. An object of the present invention is that the beverage container, fitted with a straw, can be filled with ice or beverage without knocking the straw out of the container. The internal body member serves to hold the straw upright whilst the the container is being prepared; conventional straws, unless affixed to the container tend to fall out. In part, because of the unusualness of the multi-sectional straw, it is anticipated that retailers will adapt various advertising devices and trademarks to the tubular end of the straw. The multi-sectional straw bears a strong resemblance to a horn, and this also is anticipated to have potentially important commercial ramifications. An object of the present invention is that the beverage container may be fitted with a lid and a multi-sectional drinking straw, wherein the straw is superimposed on the frustum of the internal body member and penetrates the epicenter of the lid through the straw passage, and that when the container is fitted with a lid and the multi-sectional straw, its fluid contents will be retained if the container is overturned. The present invention includes various fastening devices for securing the bifrustoconical beverage container to a fixed surface. Beverage containers, particularly cups and cans, are traditionally immoblized in a car using holders that clasp the container. An object of the present invention is that the beverage container can be either clasped or passively restrained by interpositioning the appropriate vertical fastening element within the container, and that in contrast to a clasp method of fastening, which requires a different clasp for each size of container, the interposition method of fastening enables a single device to hold various size containers. The present invention includes various food conveyance devices having one or more vertical fastening elements which project upward from a horizontal body surface on the device. Fastening devices are inclusive of conventional food trays, automobile floor and dashboard mounted trays, and car door drink holders as well as other vehicular food holders. In the case of dedicated beverage holders, such as car door drink holders which are S shaped and hook into the slot which houses the window, the beverage holder device for a bifrustoconical container has a vertical fastening element emanating from the base of the holder. The requirement for clasping or encircling side arms on the holder is obviated by the vertical fastening element, and therefore would be unnecessary. The fastening element, such as pintle, is sized such that various volume bifrustoconical containers will fit onto the holder. In the case of trays, they are traditionally designed to hold either a set number of beverage containers or are substantially flat and do not restrict movement of a beverage container if the container is placed in an accelerated state, such as when a car is turning or stopping. The present invention includes trays which are substantially flat, where the horizontal body surface of the tray is fitted with one or more vertical fastening elements that emanate from the body surface of the tray, and where the vertical fastening element may be permanent or removable from the body surface. The elements are sized such that various volume bifrustoconical containers will fit onto the tray. A preferable design of a tray suitable as a take-out tray for a past food restaurant is a substantially flat rectangular tray where the body surface of the tray has four or more cylindrical receses which can be fitted with a vertical fastening element. The tray can be modified to match the number of beverage containers on an order by order basis. An object of the present invention is that the body surface of the food conveyance device is fitted with a vertical fastening element for a bifrustoconical beverage container, and that the vertical fastening element may be removable. Another object of the invention is that one bifrustoconical beverage container can be nested within another similar container, and that the containers are stackable and nestable. A final object of the invention is that the bifrustoconical beverage container may have a handle. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a bifrustoconical beverage container which has an inverted bottom protruding upward into the interior of the container. FIG. 2 is a perspective view of the container in FIG. 1 wherein the container has been fitted with a closing lid and a multi-sectional straw. FIG. 3 is a vertical sectional view taken substantially upon the plane indicated by section line 3--3 of FIG. 2. FIG. 4 is a perspective view of the multi-sectional straw sectionally shown in FIG. 3. FIG. 5 is a perspective view of a decorative version of a multi-sectional straw. FIG. 6 is a vertical sectional view of a bifrustoconical beverage container fitted with the decorative straw shown in FIG. 5, wherein the shape of the frustoconical bottom of the container has been altered from that shown in FIG. 3 so as to match the decorative straw. FIG. 7 is a perspective view of a car door drink holder designed specifically for securing bifrustoconical beverage containers. FIG. 8 is a vertical sectional view taken substantially upon the plane indicated by section line 8--8 of FIG. 7. A vertical sectional view of a bifrustoconical beverage container has been included in FIG. 8 for clarification of how the car door drink holder works. FIG. 9 is a perspective view of a car dash board drink holder that can be adhesively mounted to flat surfaces for purposes of securing a bifrustoconical beverage container. FIG. 10 is a perspective view of a food conveyance tray which is fitted with two vertical fastening elements, one of which is being utilized. The tray has cylindrical recesses which can be fitted with additional vertical fastening elements for securing containers on an as needed basis. FIG. 11 is a perspective view of a couple of vertical fastening elements which can be fitted into the cylindrical recesses in the tray shown in FIG. 10. DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates perspectively a bifrustoconical beverage container 1 having an external body member 2 with a rim 3 and a base 4. The container 1 has an internal body member 5, shown in relief in FIG. 1 as dashed lines, which is also substantially frustoconical in shape. Internal body member 5 emanates centrally and coaxially from the epicenter of the base 4 upwardly into the container, therein forming an inverted bottom. The uppermost extremity of the internal body member frustum is closed, terminating in a hemispherically shaped apices 6, and the lowermost extremity is terminated with a flange 11, which integrally joins the internal body member 5 with the base 4 of the external body member 2, therein forming a bifrustoconical beverage container 1. In the preferred embodiment the internal body member frustum 22 is substantially smaller than the external body member frustum 2, and displaces only a relatively small portion of the apparent volume of the container. TABLE 1 lists the dimensions and volumes of several bifrustoconical containers. The diameter of the larger frustum at the rim 7, the diameter at the base 8, and the height 12 define the apparent volume of the container per the external body member frustum 2. The diameter of the smaller frustum at the apices 9, the diameter at the flange 10, and the height 13 define the displacement volume of the internal body member frustum 22. Their difference (Volume 2-Volume 22) equals the actual volume of the container. TABLE 1__________________________________________________________________________Frustum-larger Frustum-smaller Volume (oz)12 7 8(in) 13 9 10(in) Actual ApexNO. hgt. dia. dia. hgt. dia. dia. Total Above Below__________________________________________________________________________1 4.25 3.50 2.64 2.65 1.20 1.50 16.0 7.9 8.12 4.25 3.50 2.64 2.50 0.62 1.00 17.4 8.5 8.83 5.00 3.00 2.64 2.95 1.20 1.50 15.6 7.8 7.84 5.00 3.00 2.64 2.95 0.62 1.50 17.1 7.8 9.35 7.50 8.00 5.00 6.00 1.60 2.00 132.2 38.9 93.36 7.50 8.00 5.00 8.50 1.60 2.00 128.6 0.0 128.67 3.75 2.80 1.80 2.40 0.60 1.00 8.1 4.1 4.08 3.75 2.80 1.80 2.79 0.60 1.00 8.0 3.0 5.09 4.25 3.50 2.65 2.90 1.00 1.60 16.0 6.7 9.310 4.25 3.50 2.65 4.25 0.94 1.20 16.0 0.0 16.011 4.25 3.50 2.64 0.00 0.00 0.00 18.1 -- --12 0.00 0.00 0.00 2.65 1.20 1.50 -2.1 -- --13 3.75 2.80 1.80 0.00 0.00 0.00 8.8 -- --14 0.00 0.00 0.00 2.79 0.60 1.00 -0.8 -- --__________________________________________________________________________ In Table 1, No 1-10 list the dimensions and calculated actual volumes of several bifrustoconical containers. The height of the smaller frustum has been sized such that even when the container is full, more than half of the fluid volume would be located below the level of the apicies 6 of the internal body member. This choice of dimensions results in a container having a center of gravity, wherein a portion of the the bottom is actually located higher than the center of gravity of the container 1. Therefore, a container fastened at the apex would tend to be self righting with the larger fluid ballast located lower than the point of attachment. In Table 1, No 11-12 are volumetric breakdowns of container No. 1, and No 13-14 are breakdowns of container No 8. No 5 and 6 are gallon containers. FIG. 2 is a perspective view of a bifrustoconical container 1 fitted with a multi-sectional straw 14 and a sealing lid 15. The straw 14 has corrugated ribbing 16 that enables it to be bent without crimping. FIG. 3 is a vertical sectional view of FIG. 2 taken along sectional line 3-3. Multi-sectional straw 14 is superimposed on the frustum 22 of the internal body member 5. The straw is comprised of three sections, the upper essentially tubular section 17, the frustoconical section 19, and the expander section 18, which integrally joins section 17 and section 19. The straw's frustoconical section 19 is just slightly larger than the internal body member frustum 22, and 19 extends to very near the flange 11, which is the lowermost bottom of the container. There is a thin annular chamber 20 formed by the superimposed frustums, and, under the force of gentle suction, the fluid beverage is pulled into the straw through the gap 24 between the perimeter of lower extremity of the frustoconical section 19 of the straw and the flange 11 of the internal body member. The fluid is transported upward through the thin annular chamber 20, into the expander section 18 of the straw and through the tubular section 17, where it exits the top. The core 23 of the internal body member frustum 22 is hollow, and open from the underside of the container 1. The core 23 serves as a fastening element for the container when an interpositioning vertical fastening element such as a peg or a pintle is inserted into the core. FIG. 4 is a perspective view of the straw 14 sectionally shown in FIG. 3. The illustrated straw is not been bent, so that it may be pushed through the straw passage in the lid 15. FIG. 5 is a perspective view of a decorative version 34 of the multi-sectional straw 14 that has been constructed to look like a horn. The unique design of a multi-sectional straw has obvious novelty appeal, and, as such, lends itself to be fashioned into various toys and promotional paraphernalia to commercially utilize this novelty. FIG. 6 is a vertical sectional view of a bifrustoconical beverage container 1 fitted with a decorative multi-sectional straw 34 having a transitionally less pronounced expander section 18 joining the tubular section 17 to the frustoconical section 19. The inside wall of the frustoconical section of the straw has inwardly projecting point like protuberances 25 which hold the straw 34 away from from the internal body member frustum 22, therein establishing the width of the annular chamber 20. In order to accommodate the essentially conically shaped straw, the internal body member has a more nearly pure conical shape, and, in particular, the apicies 6 is substantially less rounded, and much more tapered. The bifrustoconical beverage container can be temporarily secured to a position on a food conveyance holder (for instance a tray or a drink holder) with a variety of fastening devices, all of which have a vertical fastening element in common. The vertical fastening element inserts through the bottom of the container into the open ended hollow core 23 of the internal body member. FIG. 7 is a perspective view of a car door drink holder 27 with a singular vertical fastening element 26. The top 28 of the "S" shaped holder 27 hooks into the window slot. The vertical fastening element 26 projects upward from a flat horizontal plate 29 comprising a lower portion of the holder 27. FIG. 8 sectionally shows a vertical fastening element 26 that has been molded into the body of the plate 29 of the car door drink holder 27. The element 26 is sized so that it can be interpositioned essentially completely within the hollow core 23 of the internal body member frustum 22. Another holder device 32 used to secure a bifrustoconical beverage container 1 in a vertical is shown in FIG. 9. The vertical fastening element is mounted on a structural rectangular base 30, the underside of which is adhesively coated for bonding the device 32 to a fixed planar surface, such as the dash board of a car or a window sill. Another adaptation of food conveyance holders is shown in FIG. 10. The tray 33 is fitted with two vertical fastening elements 26, one of which is obscured from view by the resting secured beverage container 1. Bifrustoconical beverage container 1 has a handle 36 to improve handleability. The body of the tray has two cylindrical depressions 35 into which can be fitted additional vertical fastening elements 26, therein enabling very easy modification of the tray 33 to accommodate additional beverages. The tray has the advantage that with detachable vertical fastening elements, substantially all of its planar surface can be utilized to hold non-spillable foods or it can, alternatively, be adapted to hold multiple containers 1. The detachable vertical fastening elements 26 are shown in FIG. 11. The length of the element has been extended to include a detachable means which interlocks with the cylindrical depressions 35 in the tray 33.
A beverage container having a bottom that has been deformed such that it has a fingerlike projection that extends upward over halfway into the center of the container, where the container also has a multi-sectional drinking straw that fits over and is held upright by the projection and a closing lid that snaps on the rim. The beverage container is substantially bifrustoconical in shape, and it can be secured to a tray or drink holder equipped with a vertical element that inserts into the hollow deformation in the bottom.
Briefly outline the background technology and the problem the invention aims to solve.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to beverage containers and more particularly to a disposable non-spillable beverage container having the traditional cup-like frustoconical form and a container bottom where the bottom consists of a, second, smaller inverted capped conical frustum, emanating from the base of the container, where the frustum serves as an integral element of a special straw and as a fastening element.", "The invention also relates to accoutering components that enhance the utility of the beverage container;", "more particularly a special straw, a lid, and various fastening devices for securing the beverage container.", "Description of the Prior Art The prior art has a number of patents that read on cup-like beverage containers where the cup has been modified to be inclusive of an integral straw.", "Leeds'", "3,558,033 discloses a cup with a built in telescoping drinking straw secured to the inside surface of the cup.", "H. J. Drown discloses in his patent 2,948,453 a nonspillable liquid drinking container comprised of a cup, a lid, and a bendable straw that penetrates through an aperture in the lid.", "U.S. Pat. No. 4,573,631 reads on a beverage container having an integral straw, lid, cup combination.", "The straw and the lid are incorporated into the body of the cup itself.", "SUMMARY OF THE INVENTION The beverage container of the present invention includes a substantially frustoconically shaped external body member terminating in a rim at the upper extremity and a base at the lower extremity, where the base is contiguous with an internal body member that is substantially a second, smaller inverted, conical hollow core frustum terminating in an apical closure at the upper extremity and a joining flange at the lower extremity, where the flange integrally joins the internal body member with the base of the external body member, therein forming a bifrustoconical beverage container.", "The frustum of the internal body member emanates centrally, coaxially and upwardly from the base, the combination of the capped frustum and the flange of the internal body member therein forming the bottom of the container.", "The height of the frustum of the internal body member is, preferably, such that no more than half of the total volume of the total bifrustoconical container is located in the spatial region of the container defined by points consisting of a horizontal plane drawn through the external body member at the apices of the internal body member, the perimeter of the external body member, and a horizontal plane drawn through the rim of the external body member.", "An object of this preferred height of the frustum of the internal body member is to structure the geometry of the container such that when the container is filled, the center of gravity of the container is below the apex of the internal body member.", "A second object of the present invention is that the container can be secured by inserting, through the open ended hollow core frustoconical bottom of the container, a mounted vertical fastening element, for instance a mounted pintle or peg.", "The slanted walls of the conical frustum guide the insertion centrally, therein facilitating alignment of the container into a fixed position.", "Also, if the vertical fastening element is of sufficient length to contact the underside of the apex and the vertical fastening element has a radial thickness smaller than the smaller radius of the frustum, then the beverage container, resting on the vertical element, will be self righting through a maximum angle of deflection functionally dependent on the angle of the walls of the frustum from its axis.", "The underside of the apex will serve as the pivot point, and the top of the vertical fastening element will serve as the fulcrum.", "The bifrustoconical beverage container is composed of a malleable material, preferably a resilient plastic material.", "The preferred method of manufacture is a molding process using an extrudable plastic material.", "It is anticipated that molding processes are amenable to making very complex shapes, and that variations on the basic bifrustoconical design can and will be adopted.", "For instance, the external body member could be a combination of an octabedral frustum and a conical frustum;", "and the internal body member could be Gaussian in shape.", "A third object of the present invention is that the beverage container has substantially a bifrustoconical shape, and the invention is inclusive of variations on this general design.", "The beverage container of the present invention includes a closing lid which fastens to the rim of the external body member.", "The epicenter of the lid has a closed straw passage and opening means, where the passage is of sufficient size to allow an inserted straw to snugly pass through the resulting aperture when the passage is opened.", "The passage is normally closed, unless a straw is about to be or has been inserted into the passage.", "The beverage container of the present invention includes a novel multi-sectional straw, being comprised of an upper essentially linear tubular section, a lower essentially conical frustum section, and an intermediate expander section which integrally joins the upper tubular section to the lower conical frustum section, and in particular the smaller circular end of the lower conical frustum section.", "The uppermost end of the tubular section of the straw is the exit, and, therefore is open ended, being the point of fluid conveyance to the drinker;", "and the periphery of the lowermost end of the conical section of the straw is the entrance.", "The conical section of the multisectional straw is sized so that the interior wall of the conical section will fit superimposed over substantially the entire length of the frustum of the internal body member, therein forming a thin annular chamber in between the straw and the frustum of the internal body member.", "Furthermore, the conical section of the straw is preferably sized such that the thin annular chamber has a horizontal cross-sectional area that is nearly invariant as to the height on the superimposed frustums, and that this cross-sectional area is roughly equal to the cross-sectional area of the tubular section of the straw.", "The conical section of the straw is positioned such that fluid can communicate from the lower most bottom of the container, through the straw entrance and into the thin annular chamber.", "Positioning can be affected through the use of tabs at the entrance of the straw, flutes or small protuberances on the interior walls of the conical section of the straw or any other suitable means.", "The intermediate expander section of the straw serves to expand the diameter of the tubular section of the straw up to the diameter of the conical frustum section of the straw, and through this transition, the expander section closely follows the exterior contour of the apices of the internal body member.", "As a functioning straw, fluid is drawn in radially through the periphery of the straw entrance into the thin annular chamber, upward in the superimposed frustums, into the intermediate expander section and into the tubular section of the straw.", "The drinker when consuming a very viscous beverage such as a milk shake has the option of increasing the effective diameter of the conical frustum section of the straw by simply lifting the straw upwards out of the container slightly, which increases the size of the thin annular chamber, therein making it easier to suck the contents through the straw into the drinker's mouth.", "The conical frustum section of the straw also tends to align stringy consumables like noodles, and certain soups can be eaten using this multi-sectional straw that will not pass through an conventional straw.", "An object of the present invention is that the tubular section of the multi-sectional straw has corrugated ribbing that imparts flexibility to the tubular section.", "The corrugation allow the tubular section of the straw to be bent, without crimping, therein enabling the straw to be adjusted to an angle more suitable for consumption without tilting the beverage container.", "An object of the present invention is that the beverage container, fitted with a straw, can be filled with ice or beverage without knocking the straw out of the container.", "The internal body member serves to hold the straw upright whilst the the container is being prepared;", "conventional straws, unless affixed to the container tend to fall out.", "In part, because of the unusualness of the multi-sectional straw, it is anticipated that retailers will adapt various advertising devices and trademarks to the tubular end of the straw.", "The multi-sectional straw bears a strong resemblance to a horn, and this also is anticipated to have potentially important commercial ramifications.", "An object of the present invention is that the beverage container may be fitted with a lid and a multi-sectional drinking straw, wherein the straw is superimposed on the frustum of the internal body member and penetrates the epicenter of the lid through the straw passage, and that when the container is fitted with a lid and the multi-sectional straw, its fluid contents will be retained if the container is overturned.", "The present invention includes various fastening devices for securing the bifrustoconical beverage container to a fixed surface.", "Beverage containers, particularly cups and cans, are traditionally immoblized in a car using holders that clasp the container.", "An object of the present invention is that the beverage container can be either clasped or passively restrained by interpositioning the appropriate vertical fastening element within the container, and that in contrast to a clasp method of fastening, which requires a different clasp for each size of container, the interposition method of fastening enables a single device to hold various size containers.", "The present invention includes various food conveyance devices having one or more vertical fastening elements which project upward from a horizontal body surface on the device.", "Fastening devices are inclusive of conventional food trays, automobile floor and dashboard mounted trays, and car door drink holders as well as other vehicular food holders.", "In the case of dedicated beverage holders, such as car door drink holders which are S shaped and hook into the slot which houses the window, the beverage holder device for a bifrustoconical container has a vertical fastening element emanating from the base of the holder.", "The requirement for clasping or encircling side arms on the holder is obviated by the vertical fastening element, and therefore would be unnecessary.", "The fastening element, such as pintle, is sized such that various volume bifrustoconical containers will fit onto the holder.", "In the case of trays, they are traditionally designed to hold either a set number of beverage containers or are substantially flat and do not restrict movement of a beverage container if the container is placed in an accelerated state, such as when a car is turning or stopping.", "The present invention includes trays which are substantially flat, where the horizontal body surface of the tray is fitted with one or more vertical fastening elements that emanate from the body surface of the tray, and where the vertical fastening element may be permanent or removable from the body surface.", "The elements are sized such that various volume bifrustoconical containers will fit onto the tray.", "A preferable design of a tray suitable as a take-out tray for a past food restaurant is a substantially flat rectangular tray where the body surface of the tray has four or more cylindrical receses which can be fitted with a vertical fastening element.", "The tray can be modified to match the number of beverage containers on an order by order basis.", "An object of the present invention is that the body surface of the food conveyance device is fitted with a vertical fastening element for a bifrustoconical beverage container, and that the vertical fastening element may be removable.", "Another object of the invention is that one bifrustoconical beverage container can be nested within another similar container, and that the containers are stackable and nestable.", "A final object of the invention is that the bifrustoconical beverage container may have a handle.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a bifrustoconical beverage container which has an inverted bottom protruding upward into the interior of the container.", "FIG. 2 is a perspective view of the container in FIG. 1 wherein the container has been fitted with a closing lid and a multi-sectional straw.", "FIG. 3 is a vertical sectional view taken substantially upon the plane indicated by section line 3--3 of FIG. 2. FIG. 4 is a perspective view of the multi-sectional straw sectionally shown in FIG. 3. FIG. 5 is a perspective view of a decorative version of a multi-sectional straw.", "FIG. 6 is a vertical sectional view of a bifrustoconical beverage container fitted with the decorative straw shown in FIG. 5, wherein the shape of the frustoconical bottom of the container has been altered from that shown in FIG. 3 so as to match the decorative straw.", "FIG. 7 is a perspective view of a car door drink holder designed specifically for securing bifrustoconical beverage containers.", "FIG. 8 is a vertical sectional view taken substantially upon the plane indicated by section line 8--8 of FIG. 7. A vertical sectional view of a bifrustoconical beverage container has been included in FIG. 8 for clarification of how the car door drink holder works.", "FIG. 9 is a perspective view of a car dash board drink holder that can be adhesively mounted to flat surfaces for purposes of securing a bifrustoconical beverage container.", "FIG. 10 is a perspective view of a food conveyance tray which is fitted with two vertical fastening elements, one of which is being utilized.", "The tray has cylindrical recesses which can be fitted with additional vertical fastening elements for securing containers on an as needed basis.", "FIG. 11 is a perspective view of a couple of vertical fastening elements which can be fitted into the cylindrical recesses in the tray shown in FIG. 10.", "DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates perspectively a bifrustoconical beverage container 1 having an external body member 2 with a rim 3 and a base 4.", "The container 1 has an internal body member 5, shown in relief in FIG. 1 as dashed lines, which is also substantially frustoconical in shape.", "Internal body member 5 emanates centrally and coaxially from the epicenter of the base 4 upwardly into the container, therein forming an inverted bottom.", "The uppermost extremity of the internal body member frustum is closed, terminating in a hemispherically shaped apices 6, and the lowermost extremity is terminated with a flange 11, which integrally joins the internal body member 5 with the base 4 of the external body member 2, therein forming a bifrustoconical beverage container 1.", "In the preferred embodiment the internal body member frustum 22 is substantially smaller than the external body member frustum 2, and displaces only a relatively small portion of the apparent volume of the container.", "TABLE 1 lists the dimensions and volumes of several bifrustoconical containers.", "The diameter of the larger frustum at the rim 7, the diameter at the base 8, and the height 12 define the apparent volume of the container per the external body member frustum 2.", "The diameter of the smaller frustum at the apices 9, the diameter at the flange 10, and the height 13 define the displacement volume of the internal body member frustum 22.", "Their difference (Volume 2-Volume 22) equals the actual volume of the container.", "TABLE 1__________________________________________________________________________Frustum-larger Frustum-smaller Volume (oz)12 7 8(in) 13 9 10(in) Actual ApexNO.", "hgt.", "dia.", "dia.", "hgt.", "dia.", "dia.", "Total Above Below__________________________________________________________________________1 4.25 3.50 2.64 2.65 1.20 1.50 16.0 7.9 8.12 4.25 3.50 2.64 2.50 0.62 1.00 17.4 8.5 8.83 5.00 3.00 2.64 2.95 1.20 1.50 15.6 7.8 7.84 5.00 3.00 2.64 2.95 0.62 1.50 17.1 7.8 9.35 7.50 8.00 5.00 6.00 1.60 2.00 132.2 38.9 93.36 7.50 8.00 5.00 8.50 1.60 2.00 128.6 0.0 128.67 3.75 2.80 1.80 2.40 0.60 1.00 8.1 4.1 4.08 3.75 2.80 1.80 2.79 0.60 1.00 8.0 3.0 5.09 4.25 3.50 2.65 2.90 1.00 1.60 16.0 6.7 9.310 4.25 3.50 2.65 4.25 0.94 1.20 16.0 0.0 16.011 4.25 3.50 2.64 0.00 0.00 0.00 18.1 -- --12 0.00 0.00 0.00 2.65 1.20 1.50 -2.1 -- --13 3.75 2.80 1.80 0.00 0.00 0.00 8.8 -- --14 0.00 0.00 0.00 2.79 0.60 1.00 -0.8 -- --__________________________________________________________________________ In Table 1, No 1-10 list the dimensions and calculated actual volumes of several bifrustoconical containers.", "The height of the smaller frustum has been sized such that even when the container is full, more than half of the fluid volume would be located below the level of the apicies 6 of the internal body member.", "This choice of dimensions results in a container having a center of gravity, wherein a portion of the the bottom is actually located higher than the center of gravity of the container 1.", "Therefore, a container fastened at the apex would tend to be self righting with the larger fluid ballast located lower than the point of attachment.", "In Table 1, No 11-12 are volumetric breakdowns of container No. 1, and No 13-14 are breakdowns of container No 8.", "No 5 and 6 are gallon containers.", "FIG. 2 is a perspective view of a bifrustoconical container 1 fitted with a multi-sectional straw 14 and a sealing lid 15.", "The straw 14 has corrugated ribbing 16 that enables it to be bent without crimping.", "FIG. 3 is a vertical sectional view of FIG. 2 taken along sectional line 3-3.", "Multi-sectional straw 14 is superimposed on the frustum 22 of the internal body member 5.", "The straw is comprised of three sections, the upper essentially tubular section 17, the frustoconical section 19, and the expander section 18, which integrally joins section 17 and section 19.", "The straw's frustoconical section 19 is just slightly larger than the internal body member frustum 22, and 19 extends to very near the flange 11, which is the lowermost bottom of the container.", "There is a thin annular chamber 20 formed by the superimposed frustums, and, under the force of gentle suction, the fluid beverage is pulled into the straw through the gap 24 between the perimeter of lower extremity of the frustoconical section 19 of the straw and the flange 11 of the internal body member.", "The fluid is transported upward through the thin annular chamber 20, into the expander section 18 of the straw and through the tubular section 17, where it exits the top.", "The core 23 of the internal body member frustum 22 is hollow, and open from the underside of the container 1.", "The core 23 serves as a fastening element for the container when an interpositioning vertical fastening element such as a peg or a pintle is inserted into the core.", "FIG. 4 is a perspective view of the straw 14 sectionally shown in FIG. 3. The illustrated straw is not been bent, so that it may be pushed through the straw passage in the lid 15.", "FIG. 5 is a perspective view of a decorative version 34 of the multi-sectional straw 14 that has been constructed to look like a horn.", "The unique design of a multi-sectional straw has obvious novelty appeal, and, as such, lends itself to be fashioned into various toys and promotional paraphernalia to commercially utilize this novelty.", "FIG. 6 is a vertical sectional view of a bifrustoconical beverage container 1 fitted with a decorative multi-sectional straw 34 having a transitionally less pronounced expander section 18 joining the tubular section 17 to the frustoconical section 19.", "The inside wall of the frustoconical section of the straw has inwardly projecting point like protuberances 25 which hold the straw 34 away from from the internal body member frustum 22, therein establishing the width of the annular chamber 20.", "In order to accommodate the essentially conically shaped straw, the internal body member has a more nearly pure conical shape, and, in particular, the apicies 6 is substantially less rounded, and much more tapered.", "The bifrustoconical beverage container can be temporarily secured to a position on a food conveyance holder (for instance a tray or a drink holder) with a variety of fastening devices, all of which have a vertical fastening element in common.", "The vertical fastening element inserts through the bottom of the container into the open ended hollow core 23 of the internal body member.", "FIG. 7 is a perspective view of a car door drink holder 27 with a singular vertical fastening element 26.", "The top 28 of the "S"", "shaped holder 27 hooks into the window slot.", "The vertical fastening element 26 projects upward from a flat horizontal plate 29 comprising a lower portion of the holder 27.", "FIG. 8 sectionally shows a vertical fastening element 26 that has been molded into the body of the plate 29 of the car door drink holder 27.", "The element 26 is sized so that it can be interpositioned essentially completely within the hollow core 23 of the internal body member frustum 22.", "Another holder device 32 used to secure a bifrustoconical beverage container 1 in a vertical is shown in FIG. 9. The vertical fastening element is mounted on a structural rectangular base 30, the underside of which is adhesively coated for bonding the device 32 to a fixed planar surface, such as the dash board of a car or a window sill.", "Another adaptation of food conveyance holders is shown in FIG. 10.", "The tray 33 is fitted with two vertical fastening elements 26, one of which is obscured from view by the resting secured beverage container 1.", "Bifrustoconical beverage container 1 has a handle 36 to improve handleability.", "The body of the tray has two cylindrical depressions 35 into which can be fitted additional vertical fastening elements 26, therein enabling very easy modification of the tray 33 to accommodate additional beverages.", "The tray has the advantage that with detachable vertical fastening elements, substantially all of its planar surface can be utilized to hold non-spillable foods or it can, alternatively, be adapted to hold multiple containers 1.", "The detachable vertical fastening elements 26 are shown in FIG. 11.", "The length of the element has been extended to include a detachable means which interlocks with the cylindrical depressions 35 in the tray 33." ]
RELATED APPLICATION [0001] This application is a divisional of U.S. patent application Ser. No. 13/145,748, which is a U.S. National Stage of International PCT Application No. PCT/US2010/22266, Filed on 27 Jan. 2010, which Claims the Benefit of U.S. Provisional Application No. 61/147,826, filed on 28 Jan. 2009, each of which are hereby incorporated by reference herein. SUMMARY OF THE INVENTION [0002] One aspect of the technology implements the multiplying element and DAC as a differential current mode device. [0003] One aspect of the technology uses weighted addition deferred after multiplication of the DAC/Multiplier combination, allowing substantially equal DAC weights in columns of the differential current multiplier independent of bit position. [0004] One aspect of the technology uses non-radix2 in the addition deferred after multiplication, operating the DAC as a partially segmented DAC, with correspondingly higher accuracy. [0005] One aspect of the technology rotates or otherwise scrambles the bit allocation for elements in a segmented DAC, such as cases where the DAC is a segmented DAC and the scrambling is on the equally weighted segments. [0006] One aspect of the technology implements the DAC by selectively enabling duplicates of the devices on the input port of the multiplier. [0007] One aspect of the technology modifies the effective length of the DAC dependent upon the particular coefficient value by selecting neither of the duplicates of the devices on the input port of the multiplier, consequently enhancing the signal to noise ratio of the CSF and reducing its current. [0008] One aspect of the technology uses one, some, or all the techniques described herein in a complex filter (one operating on complex numerical quantities) where the subtraction and addition is in the current domain, and two resistor networks rather than the expected four, are used to complete the weighted addition. BRIEF DESCRIPTION OF THE DRAWINGS [0009] FIG. 1 shows an example of a semi-analog FIR. [0010] FIG. 2 shows another example of a semi-analog FIR [0011] FIG. 3 shows an example of a simple multiplier. [0012] FIG. 4 is an example graph of a multiplier response including a linear region. [0013] FIG. 5 shows an example of a simple multiplier. [0014] FIG. 6 shows an example of a multiplier with a binary control reversing the sign of the multiplier. [0015] FIG. 7 shows an example of a single coefficient DAC summing different weights. [0016] FIG. 8 shows an example of a complete DAC summing different weights. [0017] FIG. 9 shows an example of a non-radix 2 segmented DAC. [0018] FIG. 10 shows an example of a simple multiplier with a single device current source. [0019] FIG. 11 shows an example of a simple multiplier with a switchable pair of device current sources. [0020] FIG. 12 is a graph of the coefficients of an example FIR filter. [0021] FIG. 13 is a graph of the response of an example FIR filter. [0022] FIG. 14 is a graph of the coefficients of an example FIR filter scaled to 2047. [0023] FIG. 15 is a table of all coefficients of an example FIR filter. [0024] FIG. 16 shows an example of a DAC with reducible length. [0025] FIG. 17 is a table of example encodings of bits, in a DAC configuration which does not reduce the length of the DAC. [0026] FIG. 18 is a table of example encodings of bits, in a DAC configuration which does reduce the length of the DAC. [0027] FIG. 19 shows a block diagram of a complex filter sharing a common resistor network between multiple real filter components of the complex filter. DETAILED DESCRIPTION [0028] An improved tuner such as for television relies on a Channel Select Filter (CSF) to define channel selection via frequency shaping, after the coarse tuning of a preceding Radio Frequency Digital Sampling Mixer (RFDSM). The quadrature output channels of the RFDSM operate at a variable internal intermediate frequency (IF), such as in a range of 8 to 14.5 MHz. The CSF is a complex semi-analog finite impulse response (FIR) filter. The complex filter operates upon signals represented as complex numbers, expressed as an in-phase signal and a quadrature signal (I and Q). The complex filter includes multiple FIR filters of taps (e.g., 160 taps) utilizing a digital-to-analog converter (DAC) at each tap position to generate the coefficient value. A set of samples of the signal are passed down a delay line and each is multiplied by the coefficient and summed to a single output. Four such filters are arranged to process the complex quadrature signals from the RFDSM. Consequently the CSF can select either the positive or the negative output frequency, suppressing the unwanted one of the pair. [0029] The coefficients in the CSF are digital words, each independently adjustable. Because of this ability to change the coefficients, aspects of the CSF to be adjusted, such as bandwidth, steepness of band-edge, stop band rejection, or other frequency response shape. In response to a user selected channel and a subsequent adjustment of the RFDSM around a new internal IF frequency, the coefficients the CSF coefficients adjust to define a channel selection mask. Calibration is not required, as the CSF is precisely related to the clock and the filter shape achievable with the coefficients of the CSF are mathematically exact. [0030] Additional details are described as follows. The CSF has an array of sample-and-hold circuits associated with a multiplier core and a digital-to-analog converter (DAC), e.g. 12 bit DAC. In the complex filter configuration, four banks of multiplier/DAC elements are arranged, e.g. four banks of 160 multiplier/DAC elements totaling 640 such multiplier/DAC elements. In the CSF FIR filter, the sample is analog and the multiplicand is the DAC output value. The rate of passage of the signal down the array of samplers is determined by the clock. Therefore the frequency shaping and the overall response characteristic are directly related to the clock with no error due to the value of on-chip components. Consequently, the band edge, for example, is precise. [0031] The filter implements any shape with precision, limited by the 160 elements, per the Parks-McClellan algorithm sometimes referred to as the Remez Exchange algorithm. Because the preceding RFDSM is restricted to certain frequencies, the CSF constantly adjusts its bandpass position to center around the downmixed required signal. A ROM of precalculated coefficient values is provided on chip and a small DSP engine selects and loads the appropriate coefficient set given the user's selected receive frequency. In another embodiment, the CSF coefficients are loaded from the Inter-Integrated Circuit (I2C), subject to time constraints of loading. [0032] Because the CSF is a sampled data system which samples the input signals (I and Q) from the RFDSM, an anti-aliasing filter (AAF) prevents the alias signal in continuous time, without affecting the band shaping. In one embodiment, the AAF is implemented with on-chip metal finger capacitors and poly-silicon resistors and is sufficiently precise to meet requirements without calibration. [0033] Semi Analog Finite Impulse Response Filter [0034] A Semi Analog Finite Impulse Response Filter (FIR) is a transversal filter implemented with coefficient values and samples, one of which is essentially digital and one of which is analog. Typically, the sample is analog and the coefficient is digital. The multiplication and summation to output is done in the analog domain, requiring that the digital coefficient value is rendered into an analog signal by a DAC, as shown in FIG. 1 . [0035] An issue with the semi-analog FIR filter of FIG. 1 is that implementation of the chain of Sample and Hold Amplifiers (SHA) is technically difficult, since each sample must progress down the chain at the sample interval; each sample experiences an imperfection, due to gain error, noise and so forth, resulting in a significantly corrupted sample in the final (right-most) SHA. Consequently, the architecture of FIG. 1 is rarely implemented (except perhaps in CCD devices where the passage of the signal from input to output of the SHA occurs with very low error). [0036] FIG. 2 shows a semi-analog FIR filter with rotated coefficients, an innovation that allows a “round robin” action in the analog sampler. Therefore any given analog sample is only processed once; it need not pass down a chain of SHAs. This represents a significant improvement. An undesirable consequence of this method is the appearance of fixed pattern noise due to coefficient value rotation. [0037] The following will focus on the implementation of a semi analog FIR filter with rotating coefficients and implementation of the DAC and multiplier. [0038] FIG. 3 shows a simple multiplication available in an electronic circuit: a pair of three-terminal devices is used in the “long tailed pair” configuration with an adjustable tail current. (The drawing shows NMOS and the tail current IS, but just many other devices, e.g. bipolar, JFET, PMOS, etc. can be used). As the input parameter—the voltage between C and D—is changed, the output parameter—the voltage between A and B—also changes. [0039] The relation of output change to input change is shown in the graph of FIG. 4 . A typical S curve results. Symmetry results in a zero output for zero input independent of IS, and, due to the finite IS, the limit for large input must be an output of amplitude +/−IS*R. Multiplication action over a small linear range is apparent for inputs near zero; in this area the output parameter is proportional to the product of the current IS and the input value V(C,D). Analog multipliers exploit this region of multiplication action to varying degrees of sophistication. The Gilbert multiplier is a combination of three such elemental multipliers. [0040] If the source IS was replaced by a DAC, and if the input parameter V(C,D) was the SHA output, such a simple multiplier may be viable as the DAC/Multiplier combination in a semi-analog FIR filter. Although the CSF can this simple multiplying core, our technology addresses a number of problems, not least of which are that the IS parameter is uni-polar, and the accuracy of this multiplier structure would be a limitation. [0041] Multiplication in Differential Current Mode [0042] The circuit of FIG. 5 is the simple multiplier. Signals near zero applied differentially to the SHA input port (SHA and SHAb—meaning “SHA-bar”—define the input port) are multiplied by the value of the current as set in the Current Mode DAC and appear as a voltage at the output port (between Out and Outb). This circuit of FIG. 5 has some disadvantages. For example, the DAC must always draw current out of the sources of M 1 and M 2 , it cannot reverse in sign, and hence it is uni-polar. [0043] The circuit of FIG. 6 solves the uni-polar problem. The apparent sign of the DAC is reversed by activating the “reversing switch” arrangement on M 1 - 4 (as controlled by Bit and Bitb). This circuit is distinct from the Gilbert multiplier, because the input Bit/Bitb is a binary control, i.e. two state, routing the output of M 5 to R 1 and M 6 to R 2 , or conversely M 5 to R 2 and M 6 to R 1 . [0044] It is difficult to use the circuit of FIG. 6 to make the current mode DAC, since the DAC (which is ultimately going to be the source of our FIR coefficients) must rotate and rapidly and accurately change coefficient values. However, this current mode DAC is replaced with a constant current. The reversing switch arrangement is a one-bit DAC on its own, even if the DAC is fixed. Say that the DAC in FIG. 6 were simply set to a constant current, such as 10 uA. Then, if the Bit and Bitb signal were set to connect M 5 to R 1 and M 6 to R 2 , we are multiplying the input signal (on SHA/SHAb) by +10 uA. But if the reversing switch were activated to connect M 5 to R 2 and M 6 to R 1 we are multiplying by −10 uA. Accordingly, we have two possible values of +10 uA or −10 uA; that is, we have one bit of control. Because each DAC/multiplier element has a single bit associated with the multiplication, the circuit operation is simpler. [0045] Summing with Different Weights in the Output of One Coefficient DAC [0046] To extend this to more than one bit, rather than varying the current source, replicas of the circuit with fixed current source are added, as in FIG. 7 . The common current source values avoid the problem of different switching speeds of current sources having varying magnitudes, especially between the largest magnitude current source and the smallest magnitude current source. Weighting, which would otherwise be performed by the varying current source magnitudes, is deferred until after the multiplication within the DAC cell. Accordingly, each DAC cell works on substantially equal currents. [0047] The SHA input is shared, but the Bit is separate. The outputs add in a resistor network that applies a variable gain to the output node. The right hand block (controlled by Bit 2 /Bit 2 b ) contributes an amount to the output that is two times that contribution of the middle block (controlled by Bit 1 /Bit 1 b ), determined by the value of the resistors R 9 and R 10 in relation to R 5 and R 6 . The left hand block (controlled by Bit 0 /Bit 0 b ) contributes half again of the middle bit. The resistors make an R- 2 R ladder network with terminating resistor R 11 . Consequently, we have a three bit equivalent DAC. [0048] Although we have a DAC, there is no variable current source and the multiplier core devices (M 5 / 6 , M 7 / 10 and M 13 / 16 ) work at the same constant current. This ensures good linearity. If the currents were to differ, the multiplication constant would change. To further clarify the operation at this point we can explicitly write the descriptive equation: [0000] Out = B 3 · SHA + B 2 · SHA 2 + B 3 · SHA 4 = SHA  ( B 3 + B 2 2 + B 1 4 ) [0049] where B n ={−1,+1}. Clearly we have a 3 bit DAC multiplying the SHA. [0050] Summing with Different Weights in the Output of a Complete FIR Filter [0051] This DAC is to be used in the CSF, i.e. in a semi-analog FIR filter. FIG. 8 shows a complete three tap, three bit DAC example. The addition of the multiplication which is weighted by the DAC, can be deferred yet again, and that the resistor network to do the addition occurs one time in this FIR filter. [0052] Columns of similarly weighted multiplier cores are connected together. It is not required to provide a separate resistor network for each one. FIG. 8 also makes clear the sample and hold for each DAC row. The data in the DAC is not the same; the names Bit<n><m> indicate that all 9 data bits in this example are distinct. This technology is extensible in both DAC bus width and number of FIR taps. In a Complex Filter using this technology, only two resistor networks are needed, despite the fact that four complete FIR filters are used in such a filter. [0053] Using Non-Radix 2 to Provide Enhanced Accuracy and Segmented Operation [0054] Up to this point the limitation of accuracy of the equivalent DAC is due to the resistor mismatch. If these resistors match to 0.1% then the overall DAC is correspondingly 0.1% accurate. Addition of more multiplier cells can improve this by converting the DAC to a partially so-called “segmented” DAC architecture. For example, three multiplier cores can add to make one compound core that has four possible operating conditions, as shown in FIG. 9 . [0055] Three of the multiplier sections add their output currents together into one resistor load network. That network then connects to the next compound group, not with a weight of (½), but with a weight of (¼). The effect of this is that two bits are available in each group of three cores and the resistors then provide the remaining relative weights. The burden on the resistor matching is therefore somewhat reduced and the DAC will have a high accuracy. Two bits are available from the three core cells, because the possible states are as shown in the following table, namely that there are four possible outputs −3, −1, +1, +3, the −1 and +1 states occurring multiple times. [0000] Left Middle Right Result 0 0 0 −3 0 0 1 −1 0 1 0 −1 0 1 1 1 1 0 0 −1 1 0 1 1 1 1 0 1 1 1 1 +3 [0056] The redundancy in the codes is exploited in the programming sequence. For example, the three codes that represent −1 are each chosen in turn when needed. This differs from a typical decision to choose say, L=0,M=0,R=1 as the code for −1 all the time and causes the mismatch that may exist between Left Middle and Right cells to be scrambled. [0057] The choice of three sections per bit is exemplary. More sections can be chosen, and further that the segmentation need not continue to the LSB—by the time we reach the LSB bit positions the inherent matching is more than adequate to meet requirements. Various embodiments do not segment one or more of the lower order bits. In summary, operation with other than radix two gives two benefits: the resistor need not match the equivalent DAC accuracy, hence system accuracy is improved; and secondly redundancies in coding may be exploited to “scramble” and matching error within a segment group. [0058] Selectively Enabling Duplicate Input Devices [0059] The fixed current source that replaced the DAC in various embodiments has been shown as a symbol, not exposing the actual transistors that make up the current source. Some embodiments use a current source as follows. [0060] FIG. 10 shows the multiplier core with reversing switch arrangement where the current source is now seen to be a single device (M 7 ) operating at a fixed bias. The presence of additional resistance in the source of M 7 does not, in general, degrade the operation of the current source. FIG. 11 removes the reversing switch arrangement and substitutes a second input pair connected opposite to the first. The ‘Bit’ input activates one of two current source devices and determines which input group is active and chooses multiplication by +1 or −1. [0061] Modification to the Effective DAC Length [0062] The duplication of input pairs and removal of reversing arrangement has advantages described in the following. [0063] FIGS. 12 and 13 show a typical FIR filter. This FIR filter has 212 coefficient values. The average value of the coefficients is quite small. In this example (where the peak has been scaled to 1.0) the RMS value is about 0.19. To use the semi-analog FIR filter, the coefficients are encoded into a DAC. As an example, we encode these values into a 12 bit DAC (a DAC that can provide 4096 different output states). The numbers are signed, such that both positive and negative values are represented. Consequently the best we can do is make the peak equal to 2047, scaling the others proportionally. The resulting DAC values are shown in FIG. 14 . [0064] Each of these 212 coefficients is expressed as a DAC value in the 212 DACs that make up the semi-analog FIR filter. These DAC values will rotate as disclosed. Most of the DAC values are small. In this example, there are 36 values that are less than 10. The design can be optimized, such that when fewer than 12 bits are needed, which is quite frequently, some resource may be saved. [0065] The table of FIG. 15 shows all the coefficient values in the example FIR filter, and the number of DAC bits required to represent that particular coefficient value. The FIR filter in this example has an even number of components and is symmetric; the second set of 106 coefficients in this 212 tap example filter is a mirror-image of the first set of 106 coefficients. Only the first 106 tap values are shown in the table. Each one of these table entries appears two times in the filter. Most of the time far fewer than 12 bits are needed, and the average number of DAC bits needed is 6.8, not 12. We can take advantage of this. We review how a differential current mode DAC works, and specifically how the DAC/Multiplier of our FIR filter operates. The segmented architecture radix-4 is used as an example, but any differential current mode DAC can be used. [0066] A 12 bit radix-4 segmented current mode DAC has six two bit sections. It is made up of six groups of three elements. (Two groups of three elements are shown in the schematic on FIG. 9 .) Each of these three elements can represent −3, −1, 1 or 3, hence two binary bits. Each of these groups is then added with a weight of four to create the effective DAC value. [0067] For example, this DAC creates the equivalent of +999. It does so by encoding (from MSB to LSB) the sequence (1, −1, 3, 3, −3, 3). This can be verified by forming the summation 1*1024−1*256+3*64+3*16−3*4+3=999. The code applied to the segmented DAC sections would then be 110,100,111,111,000,111 (as appear in the table accompanying the description of FIG. 9 ). [0068] In another example, the DAC representing −27 does so by encoding (−1, 3, 3, 3, −3, 1), which is confirmed by forming the summation −1*1024+3*256+3*64+3*16−3*4+1=−27. [0069] The DAC size can be reduced. To create the number −27, we first encoded −1024, the bulk of which canceled out by adding first 768 (i.e. 3*256) then 192 (i.e. 3*64), finally leaving −27. Various embodiments dispense with adding the current and noise associated with the encoding of −1024, 768 and 192 since these values largely cancel out one another. In some specific example of encoding −27, a segmented DACs of only three groups of three is sufficient. It can encode −27 as (−1, −3, 1) as confirmed by the summation −1*16−3*4+1=−27. Accordingly, various embodiments simplify the circuitry, reduce current, and limit noise. In the differential current mode DAC, the quantity zero is represented as two currents that are the same: the current in the left branch being made equal to the current in the right branch. The difference in current is zero, and hence the two equal currents represent zero signal. But two currents are never equal, and have noise associated with them. This noise does not reduce to zero, and in fact adds root-sum-square (i.e. it increases). Consequently, an improvement is made not by the cancellation of large quantities, but by the removal of the segmented DAC currents of the higher order bits when not needed. [0070] Some DAC embodiments cannot create an even number; all numbers of such DACs are odd. (e.g., in the range −4095 to +4095 in steps of 2, with 4095 such numbers with this DAC being very nearly 12 bits.) [0071] We encode DAC values into the electronic devices when we use the duplicate input device method as shown in FIG. 16 . (compare to FIG. 9 which uses the reversing switch arrangement). [0072] The bits are shown in the table of FIG. 17 , and examples of encoding are shown. Following the schematic drawing of FIG. 16 , the LSB is on the left. The final column (#) is equal to Code0+4*Code1, as required for this simple example of two groups of three elements. [0073] In the encoding whenever a Bit is set, the corresponding Bitb is unset and so forth. We are connecting either the input pair that connects one way to the output bus, or the input pair that connects the opposite way to the output bus. Consider the table of bit states of FIG. 18 . [0074] Again we have created the same sample output values (in the # column) as in the last example. Note that, for example, Bit 10 and Bit 10 b are now both zero at the same time (as are Bit 11 /Bit 11 b and Bit 12 /Bit 12 b ). By using the ‘duplicate input device’ method, certain sections of the DAC can be shut off. This shutting off is possible when the DAC number is such that MSB sections are not needed. Alternative embodiments achieve this. A third pair of devices may have been added to the ‘reversing switch’ arrangement. But this is a convenient embodiment to shut off the DAC sections that are not needed to implement small numerical values, i.e. small coefficient values in our example. The consequence is that no current flows in certain multiplying elements and current consumption is less, so noise is less. [0075] Unlike in these simplified example embodiments where a weighted resistor network is shown associated with each DAC, in a complete filter embodiment, the resistor network occurs one time at the very ‘top’ of the filter. Consequently, as the coefficients rotate and certain of them implement this “off state” in certain multipliers, the current does not change in the weighting resistors. There is no “common mode” glitch or similar effect due to the current turning on and off; the same (lower than before) current always flows. [0076] Use of One Weighted Resistor Network Per Pair of FIRs in a Complex Filter [0077] A ‘complex filter’ in this context refers to a filter designed to operate upon data represented as complex numbers. These kinds of filter are common in communication systems. A complex filter is desirable in certain circumstances due to its ability to distinguish positive and negative frequencies. A complex filter is made from real filters as in FIG. 19 . Four FIR filters of the conventional kind are used. They generally differ in coefficient values, but in the typical case the FIR 1 and FIR 3 will have the same coefficients, as will FIR 2 and FIR 4 . The outputs are summed (or subtracted) to deliver the signal at the two output ports. These FIR filters built with the techniques described, may implement the sum and difference in the current domain, that is, before use of the weighted resistor networks. Consequently only two such resistor networks are used, rather than four such resistor networks. The two channels that are added or subtracted can be implemented interleaved, with the DAC circuits for the I and Q representing different SHA signals, but the taps otherwise interleaved. This leads to excellent matching of coefficient value and good rejection of errors. [0078] While the present invention is disclosed by reference to the preferred embodiments and examples detailed above, it is to be understood that these examples are intended in an illustrative rather than in a limiting sense. It is contemplated that modifications and combinations will readily occur to those skilled in the art, which modifications and combinations will be within the spirit of the invention and the scope of the following claims.
Channel select filter circuits are described. One circuit implements a multiplying element and digital-to-analog converter as a differential current mode device. Another circuit implementing a multiplying element and digital-to-analog converter with weighted addition, deferred after multiplication of the digital-to-analog converter and multiplier combination. In one such circuit, substantially equal current source magnitudes are in different columns of the circuit. Another such circuit, with substantially equal current source magnitudes, uses non-radix2. Another such circuit, with substantially equal current source magnitudes, has partial segmentation. Another circuit implements a multiplying element and digital-to-analog converter, with partial segmentation, scrambling bit allocation for elements. One such circuit scrambles bit allocation on equally weighted segments, as described herein. Another circuit implements a multiplying element and digital-to-analog converter with selective enablement of duplicate current source devices. Another circuit implements a multiplying element and digital-to-analog converter with variable effective length of the digital-to-analog converter. In one such circuit one or more current sources of a multiplier element are deselected to remove a noise contribution of the multiplier element, as described herein. A complex filter circuit includes a pair of real finite impulse response filter circuits performing addition and subtraction in current domain, sharing a common resistor network to perform weighted addition. One such circuit further includes a second pair of real finite impulse response filter circuits performing addition and subtraction in current domain, sharing a second common resistor network to perform weighted addition.
Identify and summarize the most critical features from the given passage.
[ "RELATED APPLICATION [0001] This application is a divisional of U.S. patent application Ser.", "No. 13/145,748, which is a U.S. National Stage of International PCT Application No. PCT/US2010/22266, Filed on 27 Jan. 2010, which Claims the Benefit of U.S. Provisional Application No. 61/147,826, filed on 28 Jan. 2009, each of which are hereby incorporated by reference herein.", "SUMMARY OF THE INVENTION [0002] One aspect of the technology implements the multiplying element and DAC as a differential current mode device.", "[0003] One aspect of the technology uses weighted addition deferred after multiplication of the DAC/Multiplier combination, allowing substantially equal DAC weights in columns of the differential current multiplier independent of bit position.", "[0004] One aspect of the technology uses non-radix2 in the addition deferred after multiplication, operating the DAC as a partially segmented DAC, with correspondingly higher accuracy.", "[0005] One aspect of the technology rotates or otherwise scrambles the bit allocation for elements in a segmented DAC, such as cases where the DAC is a segmented DAC and the scrambling is on the equally weighted segments.", "[0006] One aspect of the technology implements the DAC by selectively enabling duplicates of the devices on the input port of the multiplier.", "[0007] One aspect of the technology modifies the effective length of the DAC dependent upon the particular coefficient value by selecting neither of the duplicates of the devices on the input port of the multiplier, consequently enhancing the signal to noise ratio of the CSF and reducing its current.", "[0008] One aspect of the technology uses one, some, or all the techniques described herein in a complex filter (one operating on complex numerical quantities) where the subtraction and addition is in the current domain, and two resistor networks rather than the expected four, are used to complete the weighted addition.", "BRIEF DESCRIPTION OF THE DRAWINGS [0009] FIG. 1 shows an example of a semi-analog FIR.", "[0010] FIG. 2 shows another example of a semi-analog FIR [0011] FIG. 3 shows an example of a simple multiplier.", "[0012] FIG. 4 is an example graph of a multiplier response including a linear region.", "[0013] FIG. 5 shows an example of a simple multiplier.", "[0014] FIG. 6 shows an example of a multiplier with a binary control reversing the sign of the multiplier.", "[0015] FIG. 7 shows an example of a single coefficient DAC summing different weights.", "[0016] FIG. 8 shows an example of a complete DAC summing different weights.", "[0017] FIG. 9 shows an example of a non-radix 2 segmented DAC.", "[0018] FIG. 10 shows an example of a simple multiplier with a single device current source.", "[0019] FIG. 11 shows an example of a simple multiplier with a switchable pair of device current sources.", "[0020] FIG. 12 is a graph of the coefficients of an example FIR filter.", "[0021] FIG. 13 is a graph of the response of an example FIR filter.", "[0022] FIG. 14 is a graph of the coefficients of an example FIR filter scaled to 2047.", "[0023] FIG. 15 is a table of all coefficients of an example FIR filter.", "[0024] FIG. 16 shows an example of a DAC with reducible length.", "[0025] FIG. 17 is a table of example encodings of bits, in a DAC configuration which does not reduce the length of the DAC.", "[0026] FIG. 18 is a table of example encodings of bits, in a DAC configuration which does reduce the length of the DAC.", "[0027] FIG. 19 shows a block diagram of a complex filter sharing a common resistor network between multiple real filter components of the complex filter.", "DETAILED DESCRIPTION [0028] An improved tuner such as for television relies on a Channel Select Filter (CSF) to define channel selection via frequency shaping, after the coarse tuning of a preceding Radio Frequency Digital Sampling Mixer (RFDSM).", "The quadrature output channels of the RFDSM operate at a variable internal intermediate frequency (IF), such as in a range of 8 to 14.5 MHz.", "The CSF is a complex semi-analog finite impulse response (FIR) filter.", "The complex filter operates upon signals represented as complex numbers, expressed as an in-phase signal and a quadrature signal (I and Q).", "The complex filter includes multiple FIR filters of taps (e.g., 160 taps) utilizing a digital-to-analog converter (DAC) at each tap position to generate the coefficient value.", "A set of samples of the signal are passed down a delay line and each is multiplied by the coefficient and summed to a single output.", "Four such filters are arranged to process the complex quadrature signals from the RFDSM.", "Consequently the CSF can select either the positive or the negative output frequency, suppressing the unwanted one of the pair.", "[0029] The coefficients in the CSF are digital words, each independently adjustable.", "Because of this ability to change the coefficients, aspects of the CSF to be adjusted, such as bandwidth, steepness of band-edge, stop band rejection, or other frequency response shape.", "In response to a user selected channel and a subsequent adjustment of the RFDSM around a new internal IF frequency, the coefficients the CSF coefficients adjust to define a channel selection mask.", "Calibration is not required, as the CSF is precisely related to the clock and the filter shape achievable with the coefficients of the CSF are mathematically exact.", "[0030] Additional details are described as follows.", "The CSF has an array of sample-and-hold circuits associated with a multiplier core and a digital-to-analog converter (DAC), e.g. 12 bit DAC.", "In the complex filter configuration, four banks of multiplier/DAC elements are arranged, e.g. four banks of 160 multiplier/DAC elements totaling 640 such multiplier/DAC elements.", "In the CSF FIR filter, the sample is analog and the multiplicand is the DAC output value.", "The rate of passage of the signal down the array of samplers is determined by the clock.", "Therefore the frequency shaping and the overall response characteristic are directly related to the clock with no error due to the value of on-chip components.", "Consequently, the band edge, for example, is precise.", "[0031] The filter implements any shape with precision, limited by the 160 elements, per the Parks-McClellan algorithm sometimes referred to as the Remez Exchange algorithm.", "Because the preceding RFDSM is restricted to certain frequencies, the CSF constantly adjusts its bandpass position to center around the downmixed required signal.", "A ROM of precalculated coefficient values is provided on chip and a small DSP engine selects and loads the appropriate coefficient set given the user's selected receive frequency.", "In another embodiment, the CSF coefficients are loaded from the Inter-Integrated Circuit (I2C), subject to time constraints of loading.", "[0032] Because the CSF is a sampled data system which samples the input signals (I and Q) from the RFDSM, an anti-aliasing filter (AAF) prevents the alias signal in continuous time, without affecting the band shaping.", "In one embodiment, the AAF is implemented with on-chip metal finger capacitors and poly-silicon resistors and is sufficiently precise to meet requirements without calibration.", "[0033] Semi Analog Finite Impulse Response Filter [0034] A Semi Analog Finite Impulse Response Filter (FIR) is a transversal filter implemented with coefficient values and samples, one of which is essentially digital and one of which is analog.", "Typically, the sample is analog and the coefficient is digital.", "The multiplication and summation to output is done in the analog domain, requiring that the digital coefficient value is rendered into an analog signal by a DAC, as shown in FIG. 1 .", "[0035] An issue with the semi-analog FIR filter of FIG. 1 is that implementation of the chain of Sample and Hold Amplifiers (SHA) is technically difficult, since each sample must progress down the chain at the sample interval;", "each sample experiences an imperfection, due to gain error, noise and so forth, resulting in a significantly corrupted sample in the final (right-most) SHA.", "Consequently, the architecture of FIG. 1 is rarely implemented (except perhaps in CCD devices where the passage of the signal from input to output of the SHA occurs with very low error).", "[0036] FIG. 2 shows a semi-analog FIR filter with rotated coefficients, an innovation that allows a “round robin”", "action in the analog sampler.", "Therefore any given analog sample is only processed once;", "it need not pass down a chain of SHAs.", "This represents a significant improvement.", "An undesirable consequence of this method is the appearance of fixed pattern noise due to coefficient value rotation.", "[0037] The following will focus on the implementation of a semi analog FIR filter with rotating coefficients and implementation of the DAC and multiplier.", "[0038] FIG. 3 shows a simple multiplication available in an electronic circuit: a pair of three-terminal devices is used in the “long tailed pair”", "configuration with an adjustable tail current.", "(The drawing shows NMOS and the tail current IS, but just many other devices, e.g. bipolar, JFET, PMOS, etc.", "can be used).", "As the input parameter—the voltage between C and D—is changed, the output parameter—the voltage between A and B—also changes.", "[0039] The relation of output change to input change is shown in the graph of FIG. 4 .", "A typical S curve results.", "Symmetry results in a zero output for zero input independent of IS, and, due to the finite IS, the limit for large input must be an output of amplitude +/−IS*R.", "Multiplication action over a small linear range is apparent for inputs near zero;", "in this area the output parameter is proportional to the product of the current IS and the input value V(C,D).", "Analog multipliers exploit this region of multiplication action to varying degrees of sophistication.", "The Gilbert multiplier is a combination of three such elemental multipliers.", "[0040] If the source IS was replaced by a DAC, and if the input parameter V(C,D) was the SHA output, such a simple multiplier may be viable as the DAC/Multiplier combination in a semi-analog FIR filter.", "Although the CSF can this simple multiplying core, our technology addresses a number of problems, not least of which are that the IS parameter is uni-polar, and the accuracy of this multiplier structure would be a limitation.", "[0041] Multiplication in Differential Current Mode [0042] The circuit of FIG. 5 is the simple multiplier.", "Signals near zero applied differentially to the SHA input port (SHA and SHAb—meaning “SHA-bar”—define the input port) are multiplied by the value of the current as set in the Current Mode DAC and appear as a voltage at the output port (between Out and Outb).", "This circuit of FIG. 5 has some disadvantages.", "For example, the DAC must always draw current out of the sources of M 1 and M 2 , it cannot reverse in sign, and hence it is uni-polar.", "[0043] The circuit of FIG. 6 solves the uni-polar problem.", "The apparent sign of the DAC is reversed by activating the “reversing switch”", "arrangement on M 1 - 4 (as controlled by Bit and Bitb).", "This circuit is distinct from the Gilbert multiplier, because the input Bit/Bitb is a binary control, i.e. two state, routing the output of M 5 to R 1 and M 6 to R 2 , or conversely M 5 to R 2 and M 6 to R 1 .", "[0044] It is difficult to use the circuit of FIG. 6 to make the current mode DAC, since the DAC (which is ultimately going to be the source of our FIR coefficients) must rotate and rapidly and accurately change coefficient values.", "However, this current mode DAC is replaced with a constant current.", "The reversing switch arrangement is a one-bit DAC on its own, even if the DAC is fixed.", "Say that the DAC in FIG. 6 were simply set to a constant current, such as 10 uA.", "Then, if the Bit and Bitb signal were set to connect M 5 to R 1 and M 6 to R 2 , we are multiplying the input signal (on SHA/SHAb) by +10 uA.", "But if the reversing switch were activated to connect M 5 to R 2 and M 6 to R 1 we are multiplying by −10 uA.", "Accordingly, we have two possible values of +10 uA or −10 uA;", "that is, we have one bit of control.", "Because each DAC/multiplier element has a single bit associated with the multiplication, the circuit operation is simpler.", "[0045] Summing with Different Weights in the Output of One Coefficient DAC [0046] To extend this to more than one bit, rather than varying the current source, replicas of the circuit with fixed current source are added, as in FIG. 7 .", "The common current source values avoid the problem of different switching speeds of current sources having varying magnitudes, especially between the largest magnitude current source and the smallest magnitude current source.", "Weighting, which would otherwise be performed by the varying current source magnitudes, is deferred until after the multiplication within the DAC cell.", "Accordingly, each DAC cell works on substantially equal currents.", "[0047] The SHA input is shared, but the Bit is separate.", "The outputs add in a resistor network that applies a variable gain to the output node.", "The right hand block (controlled by Bit 2 /Bit 2 b ) contributes an amount to the output that is two times that contribution of the middle block (controlled by Bit 1 /Bit 1 b ), determined by the value of the resistors R 9 and R 10 in relation to R 5 and R 6 .", "The left hand block (controlled by Bit 0 /Bit 0 b ) contributes half again of the middle bit.", "The resistors make an R- 2 R ladder network with terminating resistor R 11 .", "Consequently, we have a three bit equivalent DAC.", "[0048] Although we have a DAC, there is no variable current source and the multiplier core devices (M 5 / 6 , M 7 / 10 and M 13 / 16 ) work at the same constant current.", "This ensures good linearity.", "If the currents were to differ, the multiplication constant would change.", "To further clarify the operation at this point we can explicitly write the descriptive equation: [0000] Out = B 3 · SHA + B 2 · SHA 2 + B 3 · SHA 4 = SHA  ( B 3 + B 2 2 + B 1 4 ) [0049] where B n ={−1,+1}.", "Clearly we have a 3 bit DAC multiplying the SHA.", "[0050] Summing with Different Weights in the Output of a Complete FIR Filter [0051] This DAC is to be used in the CSF, i.e. in a semi-analog FIR filter.", "FIG. 8 shows a complete three tap, three bit DAC example.", "The addition of the multiplication which is weighted by the DAC, can be deferred yet again, and that the resistor network to do the addition occurs one time in this FIR filter.", "[0052] Columns of similarly weighted multiplier cores are connected together.", "It is not required to provide a separate resistor network for each one.", "FIG. 8 also makes clear the sample and hold for each DAC row.", "The data in the DAC is not the same;", "the names Bit<n><m>", "indicate that all 9 data bits in this example are distinct.", "This technology is extensible in both DAC bus width and number of FIR taps.", "In a Complex Filter using this technology, only two resistor networks are needed, despite the fact that four complete FIR filters are used in such a filter.", "[0053] Using Non-Radix 2 to Provide Enhanced Accuracy and Segmented Operation [0054] Up to this point the limitation of accuracy of the equivalent DAC is due to the resistor mismatch.", "If these resistors match to 0.1% then the overall DAC is correspondingly 0.1% accurate.", "Addition of more multiplier cells can improve this by converting the DAC to a partially so-called “segmented”", "DAC architecture.", "For example, three multiplier cores can add to make one compound core that has four possible operating conditions, as shown in FIG. 9 .", "[0055] Three of the multiplier sections add their output currents together into one resistor load network.", "That network then connects to the next compound group, not with a weight of (½), but with a weight of (¼).", "The effect of this is that two bits are available in each group of three cores and the resistors then provide the remaining relative weights.", "The burden on the resistor matching is therefore somewhat reduced and the DAC will have a high accuracy.", "Two bits are available from the three core cells, because the possible states are as shown in the following table, namely that there are four possible outputs −3, −1, +1, +3, the −1 and +1 states occurring multiple times.", "[0000] Left Middle Right Result 0 0 0 −3 0 0 1 −1 0 1 0 −1 0 1 1 1 1 0 0 −1 1 0 1 1 1 1 0 1 1 1 1 +3 [0056] The redundancy in the codes is exploited in the programming sequence.", "For example, the three codes that represent −1 are each chosen in turn when needed.", "This differs from a typical decision to choose say, L=0,M=0,R=1 as the code for −1 all the time and causes the mismatch that may exist between Left Middle and Right cells to be scrambled.", "[0057] The choice of three sections per bit is exemplary.", "More sections can be chosen, and further that the segmentation need not continue to the LSB—by the time we reach the LSB bit positions the inherent matching is more than adequate to meet requirements.", "Various embodiments do not segment one or more of the lower order bits.", "In summary, operation with other than radix two gives two benefits: the resistor need not match the equivalent DAC accuracy, hence system accuracy is improved;", "and secondly redundancies in coding may be exploited to “scramble”", "and matching error within a segment group.", "[0058] Selectively Enabling Duplicate Input Devices [0059] The fixed current source that replaced the DAC in various embodiments has been shown as a symbol, not exposing the actual transistors that make up the current source.", "Some embodiments use a current source as follows.", "[0060] FIG. 10 shows the multiplier core with reversing switch arrangement where the current source is now seen to be a single device (M 7 ) operating at a fixed bias.", "The presence of additional resistance in the source of M 7 does not, in general, degrade the operation of the current source.", "FIG. 11 removes the reversing switch arrangement and substitutes a second input pair connected opposite to the first.", "The ‘Bit’ input activates one of two current source devices and determines which input group is active and chooses multiplication by +1 or −1.", "[0061] Modification to the Effective DAC Length [0062] The duplication of input pairs and removal of reversing arrangement has advantages described in the following.", "[0063] FIGS. 12 and 13 show a typical FIR filter.", "This FIR filter has 212 coefficient values.", "The average value of the coefficients is quite small.", "In this example (where the peak has been scaled to 1.0) the RMS value is about 0.19.", "To use the semi-analog FIR filter, the coefficients are encoded into a DAC.", "As an example, we encode these values into a 12 bit DAC (a DAC that can provide 4096 different output states).", "The numbers are signed, such that both positive and negative values are represented.", "Consequently the best we can do is make the peak equal to 2047, scaling the others proportionally.", "The resulting DAC values are shown in FIG. 14 .", "[0064] Each of these 212 coefficients is expressed as a DAC value in the 212 DACs that make up the semi-analog FIR filter.", "These DAC values will rotate as disclosed.", "Most of the DAC values are small.", "In this example, there are 36 values that are less than 10.", "The design can be optimized, such that when fewer than 12 bits are needed, which is quite frequently, some resource may be saved.", "[0065] The table of FIG. 15 shows all the coefficient values in the example FIR filter, and the number of DAC bits required to represent that particular coefficient value.", "The FIR filter in this example has an even number of components and is symmetric;", "the second set of 106 coefficients in this 212 tap example filter is a mirror-image of the first set of 106 coefficients.", "Only the first 106 tap values are shown in the table.", "Each one of these table entries appears two times in the filter.", "Most of the time far fewer than 12 bits are needed, and the average number of DAC bits needed is 6.8, not 12.", "We can take advantage of this.", "We review how a differential current mode DAC works, and specifically how the DAC/Multiplier of our FIR filter operates.", "The segmented architecture radix-4 is used as an example, but any differential current mode DAC can be used.", "[0066] A 12 bit radix-4 segmented current mode DAC has six two bit sections.", "It is made up of six groups of three elements.", "(Two groups of three elements are shown in the schematic on FIG. 9 .) Each of these three elements can represent −3, −1, 1 or 3, hence two binary bits.", "Each of these groups is then added with a weight of four to create the effective DAC value.", "[0067] For example, this DAC creates the equivalent of +999.", "It does so by encoding (from MSB to LSB) the sequence (1, −1, 3, 3, −3, 3).", "This can be verified by forming the summation 1*1024−1*256+3*64+3*16−3*4+3=999.", "The code applied to the segmented DAC sections would then be 110,100,111,111,000,111 (as appear in the table accompanying the description of FIG. 9 ).", "[0068] In another example, the DAC representing −27 does so by encoding (−1, 3, 3, 3, −3, 1), which is confirmed by forming the summation −1*1024+3*256+3*64+3*16−3*4+1=−27.", "[0069] The DAC size can be reduced.", "To create the number −27, we first encoded −1024, the bulk of which canceled out by adding first 768 (i.e. 3*256) then 192 (i.e. 3*64), finally leaving −27.", "Various embodiments dispense with adding the current and noise associated with the encoding of −1024, 768 and 192 since these values largely cancel out one another.", "In some specific example of encoding −27, a segmented DACs of only three groups of three is sufficient.", "It can encode −27 as (−1, −3, 1) as confirmed by the summation −1*16−3*4+1=−27.", "Accordingly, various embodiments simplify the circuitry, reduce current, and limit noise.", "In the differential current mode DAC, the quantity zero is represented as two currents that are the same: the current in the left branch being made equal to the current in the right branch.", "The difference in current is zero, and hence the two equal currents represent zero signal.", "But two currents are never equal, and have noise associated with them.", "This noise does not reduce to zero, and in fact adds root-sum-square (i.e. it increases).", "Consequently, an improvement is made not by the cancellation of large quantities, but by the removal of the segmented DAC currents of the higher order bits when not needed.", "[0070] Some DAC embodiments cannot create an even number;", "all numbers of such DACs are odd.", "(e.g., in the range −4095 to +4095 in steps of 2, with 4095 such numbers with this DAC being very nearly 12 bits.) [0071] We encode DAC values into the electronic devices when we use the duplicate input device method as shown in FIG. 16 .", "(compare to FIG. 9 which uses the reversing switch arrangement).", "[0072] The bits are shown in the table of FIG. 17 , and examples of encoding are shown.", "Following the schematic drawing of FIG. 16 , the LSB is on the left.", "The final column (#) is equal to Code0+4*Code1, as required for this simple example of two groups of three elements.", "[0073] In the encoding whenever a Bit is set, the corresponding Bitb is unset and so forth.", "We are connecting either the input pair that connects one way to the output bus, or the input pair that connects the opposite way to the output bus.", "Consider the table of bit states of FIG. 18 .", "[0074] Again we have created the same sample output values (in the # column) as in the last example.", "Note that, for example, Bit 10 and Bit 10 b are now both zero at the same time (as are Bit 11 /Bit 11 b and Bit 12 /Bit 12 b ).", "By using the ‘duplicate input device’ method, certain sections of the DAC can be shut off.", "This shutting off is possible when the DAC number is such that MSB sections are not needed.", "Alternative embodiments achieve this.", "A third pair of devices may have been added to the ‘reversing switch’ arrangement.", "But this is a convenient embodiment to shut off the DAC sections that are not needed to implement small numerical values, i.e. small coefficient values in our example.", "The consequence is that no current flows in certain multiplying elements and current consumption is less, so noise is less.", "[0075] Unlike in these simplified example embodiments where a weighted resistor network is shown associated with each DAC, in a complete filter embodiment, the resistor network occurs one time at the very ‘top’ of the filter.", "Consequently, as the coefficients rotate and certain of them implement this “off state”", "in certain multipliers, the current does not change in the weighting resistors.", "There is no “common mode”", "glitch or similar effect due to the current turning on and off;", "the same (lower than before) current always flows.", "[0076] Use of One Weighted Resistor Network Per Pair of FIRs in a Complex Filter [0077] A ‘complex filter’ in this context refers to a filter designed to operate upon data represented as complex numbers.", "These kinds of filter are common in communication systems.", "A complex filter is desirable in certain circumstances due to its ability to distinguish positive and negative frequencies.", "A complex filter is made from real filters as in FIG. 19 .", "Four FIR filters of the conventional kind are used.", "They generally differ in coefficient values, but in the typical case the FIR 1 and FIR 3 will have the same coefficients, as will FIR 2 and FIR 4 .", "The outputs are summed (or subtracted) to deliver the signal at the two output ports.", "These FIR filters built with the techniques described, may implement the sum and difference in the current domain, that is, before use of the weighted resistor networks.", "Consequently only two such resistor networks are used, rather than four such resistor networks.", "The two channels that are added or subtracted can be implemented interleaved, with the DAC circuits for the I and Q representing different SHA signals, but the taps otherwise interleaved.", "This leads to excellent matching of coefficient value and good rejection of errors.", "[0078] While the present invention is disclosed by reference to the preferred embodiments and examples detailed above, it is to be understood that these examples are intended in an illustrative rather than in a limiting sense.", "It is contemplated that modifications and combinations will readily occur to those skilled in the art, which modifications and combinations will be within the spirit of the invention and the scope of the following claims." ]
TECHNICAL FIELD [0001] The present systems and methods relate to pacifiers and teethers. More particularly, present systems and methods relate to pacifiers and teethers having a frozen portion. CROSS RELATED APPLICATIONS [0002] This application is a divisional of U.S. patent application Ser. No. 13/527,135 filed on 19 Jun. 2012 and titled Frozen Pacifier and Teether. U.S. patent application Ser. No. 13/527,135 is herein incorporated by reference for all that it teaches. BACKGROUND [0003] Pacifiers have been used for many years to help sooth or pacify a baby. Some types of pacifiers include a pacifying nipple and a teething ring positioned opposite the nipple to provide both pacifying and teething functions for the baby. Pacifier nipples are typically hollow and hold a sealed volume of air. [0004] Some teething rings hold fluid or comprise materials that retain cold temperatures when stored in a cold environment. The cold teething ring may provide additional comfort for a baby with swollen gums when teething. [0005] Babies and small children are sometimes prone to receive facial injuries that result from, for example, learning to crawl or walk. Injuries to a baby's mouth can be particularly difficult to treat with cold compresses or ice because the child is uncooperative and does not understand the benefit of such treatment. [0006] Further, a number of problems exist related to giving medication or fluids to a child orally. Some babies and small children are very resistant to other people putting things into their mouth, even when such things are intended for the child's improved health or care. [0007] There is a need for improvements in treating oral injuries in children and oral delivery of medications and fluids to children that is convenient and easy to use. SUMMARY [0008] One aspect of the present disclosure relates to a pacifier system that includes a pacifier and a frozen member mold. The pacifier includes a face shield, a teething member, and a handle. The face shield includes a first side and a second side, wherein the first side has a concave surface. The teething member extends from the concave surface on the first side of the face shield. The handle extends from the second side of the face shield. The frozen member mold includes a cavity that is sized to hold a volume of frozen fluid and receives the teething member held within the frozen fluid. The teething member is configured to maintain a connection with the frozen fluid. The pacifier is removable from the frozen member mold with the frozen fluid attached to the teething member. The frozen fluid is insertable into a child's mouth to pacify the child and the teething member is configured to be chewed after the frozen fluid is removed. [0009] The teething member may include a plurality of protrusions on an exterior surface thereof. The frozen fluid may have a tapered shape. The cavity may have a nipple shape. The handle may comprise a loop-shaped portion. The face shield may be configured to contact an outer facial surface of the child when the frozen fluid is inserted into the child's mouth. The frozen member mold may include a plurality of cavities and a plurality of pacifier interfaces. The teething member may include a food grade silicone. The cavity may have a bulbous shape. The frozen member mold may include a pacifier interface configured to support the pacifier and orient the teething member within the cavity. [0010] Another aspect of the present disclosure relates to a pacifier that includes a face shield, a teething member, a handle, and a frozen fluid. The face shield may include a first side and a second side, wherein the first side is configured to contact lips or a facial surface of a child adjacent to a mouth of the child. The teething member extends from the first side of the face shield and has an exterior surface. The handle extends from the second side of the face shield and includes a grasping portion. The frozen fluid is mounted to the exterior surface of the teething member and has a nipple shape. The teething member includes a structure that retains the frozen fluid on the outer surface of the teething member. [0011] The teething member may include a plurality of protrusions formed on the exterior surface thereof. The frozen fluid may include at least one of a medication, a flavor, a color, water and a juice. The teething member may include silicone. The first side of the face shield may include a concave surface and a plurality of holes formed in the concave surface. The pacifier may be integrally formed as a single piece. [0012] A further aspect of the present disclosure relates to a method of manufacturing a frozen pacifier. The method includes forming a pacifier that includes a face shield, a teething member extending from a first side of the face shield, and a handle extending from a second side of the face shield. The method may also include forming a mold comprising a mold cavity, wherein the mold cavity is configured to be filled with a liquid and to receive the teething member. A liquid in the mold cavity is frozen to form a frozen liquid that is secured to the teething member. The frozen liquid is removed from the mold cavity while secured to the teething member and configured for insertion into a child's mouth. The teething member is configured to be chewed within the child's mouth after the frozen liquid is removed from the teething member. [0013] The method may include releasably connecting the pacifier to the mold while freezing the liquid. The method may include integrally forming the pacifier as a single piece. The method may include forming the frozen liquid with a bulbous shape. [0014] Another example method in accordance with the present disclosure relates to a method of using a pacifier system. The method includes providing a pacifier and a mold, wherein the pacifier includes a face shield, a teething member extending from a first side of the face shield, and a handle extending from a second side of the face shield. The mold includes a mold cavity having a nipple shape that is sized to fit within a child's mouth. The method may also include filling the mold cavity with a liquid, inserting a teething member into the mold cavity, freezing the liquid into a frozen liquid that is secured to the teething member, removing the teething member with the frozen liquid from the mold cavity, inserting the frozen liquid into the child's mouth to treat the child's mouth, removing the frozen liquid, and chewing on the teething member with the child's mouth after removing the frozen liquid. Removing the frozen liquid may include thawing the frozen liquid in the child's mouth. BRIEF DESCRIPTION OF THE DRAWINGS [0015] The accompanying drawings illustrate various embodiments of the principles described herein and are a part of the specification. The illustrated embodiments are merely examples and do not limit the scope of the claims. [0016] FIG. 1 is a perspective view of an example pacifier system in accordance with the present disclosure. [0017] FIG. 2 is a perspective view of a pacifier of the pacifier system of FIG. 1 . [0018] FIG. 3 is a perspective view of the pacifier of FIGS. 1 and 2 with a frozen member mounted thereon. [0019] FIG. 4 is a front view of the pacifier of FIG. 2 . [0020] FIG. 5 is a rear view of the pacifier of FIG. 2 . [0021] FIG. 6 is a cross-sectional view of the pacifier of FIG. 4 . [0022] FIG. 7 is a front view of the pacifier with the frozen member of FIG. 3 . [0023] FIG. 8 is a cross-sectional view of the pacifier and the frozen member of FIG. 7 . [0024] FIG. 9 is a front view of another example pacifier with the frozen member in accordance with the present disclosure. [0025] FIG. 10 is a cross-sectional view of the pacifier and the frozen member of FIG. 9 . [0026] FIG. 11 is a cross-sectional view of the pacifier system of FIG. 1 and the pacifier of FIG. 9 . [0027] Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. DETAILED DESCRIPTION [0028] The present disclosure relates to pacifiers, teethers, pacifiers having teething features, pacifiers with frozen members mounted thereon, molds used for frozen pacifiers, pacifier systems that include pacifiers and molds, and related methods. One aspect of the present disclosure relates to systems and methods for forming a frozen pacifier, or at least a pacifier having a frozen portion mounted on the exterior surface thereof. The frozen portion may comprise a liquid such as water, juice, or hydrating material that is solidified into a size and shape that fits within a child's mouth. A portion of the pacifier to which the frozen member is mounted on an exterior surface thereof may be configured as a teething member that the child can chew upon after the frozen member has been removed (e.g., by thawing within the child's mouth). [0029] The frozen pacifier and related pacifier system and methods disclosed herein may have certain advantages over other types of pacifiers and teething structures. The frozen pacifiers of the present disclosure incorporate a pacifier construction that is visually identified by a child as an object that provides comfort that will soothe the child. The pacifier is provided with a teething portion so that the child may chew upon the teething portion to encourage teething in the child's mouth. The teething member may be exposed after the frozen member is removed from the pacifier. The teething member may provide a substrate or structure upon which the frozen member is connected to the pacifier. In one example, the teething member includes a plurality of protrusions, dimples, shapes and sizes that promote insertion of the teething member into a child's mouth and encourage chewing on the teething member by the child. The structure and features on an exterior surface of the teething member may also promote connection of the frozen member to the pacifier. [0030] The frozen member may have a shape and size similar to the nipple of a typical pacifier. In one example, the frozen member has a bulbous shape. Other examples include a cylindrical shape with a rounded end portion and a slightly tapered sidewall. The frozen member typically has a length that provides comfortable insertion into a child's mouth until a face shield portion of the pacifier contacts the lips and other facial tissues surrounding the mouth of the child. The frozen member may be sized for different aged children such as, for example, an infant (ages 0-12 months), a toddler (ages 1-3 years), and an older child (ages 4-8 years). [0031] An example pacifier system may include a mold used to form the frozen member onto the teething member of the pacifier. The mold may include a plurality of cavities. The cavities may have different shapes and sizes to provide frozen members of different shapes and sizes. [0032] The frozen member may be used to hydrate a child that otherwise cannot or will not drink or ingest fluids. The shape and appearance of the frozen member in combination with the pacifier features of a face shield and handle may promote acceptance and use of the frozen pacifier by the child, which results in intake of liquids as the frozen member is thawed in the child's mouth. The frozen member may provide a mechanism for delivery of a medication to the child. The frozen member may include flavors, colors, aromas, and other characteristics that promote use by the child. [0033] The frozen member may also be used for treating a child that would not otherwise permit contact of a frozen object (e.g., an ice cube or ice pack) in close proximity to the child's mouth. For example, the frozen member may be used as an ice compact for a child that has received a mouth injury such as an injury to lips, gums, tongue, teeth, or palate of the child. The frozen member can be applied to the injured tissue by the child or by an adult either on an exterior facial surface of the child (e.g., on lips or facial tissues surrounding the mouth) or within the child's mouth (e.g., gums, tongue or palate). The frozen member may be shaped with contoured surfaces that provide comfortable, smooth motion over the child's facial tissue. The nipple shape of the frozen member may also induce sucking on the frozen member by the child. [0034] Referring now to FIGS. 1-8 , an example pacifier system 10 is shown including a pacifier 12 and a mold 14 . The pacifier system 10 may include a plurality of pacifiers 12 of different shapes and sizes. The mold 14 may include a plurality of cavities each sized to receive a different one of the pacifiers. The cavities may have different shapes and sizes to provide various shaped and sized frozen members attached to the pacifier. Typically, the cavities of the mold 14 are at least partially filled with a fluid. A portion of the pacifiers 12 are inserted into the cavities of the mold into contact with the fluid. The pacifier system 10 is then placed in a cold environment such as a freezer wherein the liquid is frozen to form a frozen member that is attached to the pacifiers. The pacifiers 12 with frozen members 22 are removed from the cavities of mold 14 to provide a frozen pacifier 13 as shown in FIG. 1 . [0035] The pacifier 12 includes a face shield 16 , a teething member 18 , and a handle 20 . The face shield includes front and rear surfaces 30 , 32 . The teething member 18 extends from the front surface 30 and the handle 20 extends from the rear surface 32 . The front surface 30 may be curved or contoured, and may have a concave shape (see FIG. 6 ). The curvature of the front surface 30 may match a typical curvature of a child's face in the area around a mouth of the child. [0036] The face shield 16 may also include a top edge 34 and a bottom edge 36 . The top edge 34 may include a recess 35 in the area where the top edge 34 typically would otherwise contact a nose of the child (see FIG. 4 ). The face shield 16 may have a width W 1 and a height H as shown in FIG. 4 . The width W 1 may be greater than the height H. The width W 1 of the face shield is typically in the range of about 1 inch to about 3 inches, and more preferably about 2 inches. The height H is typically in the range of about 1 inch to about 2 inches, and more preferably in the range of about 1.25 to about 1.5 inches. [0037] The teething member 18 may include proximal and distal ends 40 , 42 , side and end surfaces 44 , 46 , and a plurality of projections 48 formed on the side and end surfaces 44 , 46 (see FIGS. 4 and 6 ). In some arrangements, at least some of the projections 48 may be replaced by a plurality of recesses such as dimples. The side surface 44 is shown in FIG. 6 being relatively straight and extending perpendicular from the front surface 30 of the face shield 16 . In other examples, the teething member 18 may have different shapes and sizes such as a bulbous shape, a tapered shape, a spherical shape, etc. [0038] The teething member 18 may extend a length L 1 from the front surface 30 to face shield 16 . Typically, the length L 1 is selected to be adequate for use with children having a range of mouth sizes (e.g., infants, toddlers, or older children). The length L 1 is typically no greater than a depth of a mouth cavity of the child so that the teething member 18 does not create a choking hazard for the child. The length L 1 of the teething member 18 is typically in the range of about 0.5 inch to about 1.5 inches, and more preferably in the range of about 1 inch to about 1.5 inches. [0039] The teething member 18 may have a width W 2 that permits insertion into the child's mouth. The width W 2 (see FIG. 4 ) is typically in the range of about 0.25 inches to about 0.75 inches, and more preferably in the range of about 0.5 inches to about 0.625 inches. [0040] The projections 48 or other surface features on the side and end surfaces 44 , 46 may promote chewing of the teething member 18 by the child. Chewing on the teething member 18 may be desirable for children who are trying to cut teeth through their gums. Chewing on the teething member 18 may help wear through the gum tissue so that the cutting teeth are exposed. The surface features of the teething member 18 may be configured (e.g., sized, shaped, and arranged) to make the teething member 18 more desirable for a child to insert into its mouth and chew upon. [0041] The handle 20 may include a handle opening 50 and a handle connection portion 52 . The handle opening 50 may create a loop structure in the handle 20 so that the handle 20 is easier to grasp for purposes of carrying or maneuvering the pacifier 12 . The handle connection portion 52 may be secured to the rear surface 32 of the face shield 16 . In some arrangements, the handle 20 is connected directly to the teething member 18 and may be integrally formed with the teething member 18 . The face shield may be separately attached to one of the handle 20 and teething member 18 . [0042] In at least some arrangements, the entire pacifier 12 may be integrally formed as a single piece as shown in FIG. 6 . In other arrangements, portions of the pacifier 12 may be formed separate from the other portions and later assembled during manufacturing. For example, the handle 20 may be formed separate from the face shield 16 and teething member 18 and connected in a later assembly step using a connection method such as, for example, an adhesive, heat welding, or a snap-fit connection. [0043] Referring now to FIGS. 7 and 8 , an example frozen pacifier 13 is shown including the pacifier 12 and an additional frozen member 22 mounted thereto. The frozen member 22 includes proximal and distal ends 60 , 62 , side and end surfaces 64 , 66 , a length L 2 , and a maximum width W 3 . The length L 2 is typically no greater than a depth of a mouth cavity of the child so that the frozen member 22 does not create a choking hazard for the child. The length L 2 of the frozen member 22 is typically in the range of about 1 inch to about 2.5 inches, and more preferably in the range of about 1 inch to about 2 inches. The frozen member 22 may have a maximum width W 3 that permits insertion into the child's mouth. The width W 3 (see FIG. 7 ) is typically in the range of about 0.5 inches to about 1.5 inches, and more preferably in the range of about 0.5 inches to about 1 inch. [0044] Typically, the length L 2 is greater than the length L 1 of the teething member 18 , and the width W 3 is greater than the width W 2 of the teething member 18 so that the entire teething member 18 is encapsulated within the frozen member 22 . Encapsulating the teething member 18 within the frozen member 22 may also provide improved connection between the frozen member 22 and the teething member 18 . In some arrangements, portions of the teething member 18 may be exposed outside of the frozen member 22 prior to using the frozen pacifier 13 with a child. [0045] The frozen member 22 may have a tapered construction with a taper angle α 1 . The taper angle α 1 may be in the range of, for example, about 2° to about 20°, and more preferable in the range of about 2° to about 10°. The tapered shape of the frozen member 22 may promote easy removal of the frozen pacifier 13 from the mold 14 . [0046] Many other shapes and sizes are possible for the frozen member 22 . In one example, the frozen member 22 has a bulbous shape as shown in, for example, FIGS. 9 and 10 . The frozen member 22 may have a negative taper angle with an increasing width towards the distal end 62 . The frozen member 22 may have contoured shapes and smooth surfaces to promote easy insertion into a child's mouth. Alternatively, the frozen member 22 may have a plurality of planar surfaces and angular shapes. The frozen member 22 may have a nipple shape such as a nipple shape of pacifiers typically sold in the industry. [0047] Although not shown, the frozen member 22 may have a plurality of projections, recesses, serrations, or divots formed in the side and end surfaces 64 , 66 . The surface features of the frozen member 22 may assist in treating or soothing a child by contacting exterior facial tissue or placing the frozen member 22 within the child's mouth. The surface features of the frozen member 22 may have aesthetic benefits such as, for example, making the frozen member 22 more attractive for a child to insert into its mouth. [0048] Referring now to FIGS. 9 and 10 , another example pacifier 112 is shown having a frozen member 122 mounted therein to form a frozen pacifier 113 . The pacifier 112 includes a face shield 116 , a teething member 118 , and a handle 120 . The face shield 116 includes front and rear surfaces 130 , 132 (see FIG. 10 ), with the teething member 118 extending from the front surface 130 and the handle 120 extending from the rear surface 132 . A plurality of holes 131 may be formed in the face shield 116 to permit air to pass from the front surface 130 to the rear surface 132 . The teething member 118 may include proximal and distal ends 140 , 142 , an end surface 146 , a bulb portion 147 at the distal end 142 , and a base portion 149 at the proximal end 140 . The base portion 149 connects the teething member 118 to the face shield 116 . The handle 120 includes a handle opening 150 and a handle connection portion 152 for connection of the handle 120 to the rear surface 132 of the face shield 116 . [0049] The frozen member 122 may include proximal and distal ends 160 , 162 , an end surface 166 , a bulb portion 167 , and a base portion 169 . The frozen member 122 may have a shape that corresponds to or mirrors the shape of the teething member 118 . In other arrangements, the teething member 118 and frozen member 122 may have different shapes. For example, the teething member 118 may have a generally cylindrical shape with a circular cross-section as shown in FIGS. 1-8 , and the frozen member 122 may have a generally bulbous shape as shown in FIGS. 9 and 10 . The bulbous shape of the teething member 118 may assist in retaining the frozen member 122 on an outer surface thereof. The teething member 118 may include other shapes, sizes, and surface features that assist in maintaining the frozen member 122 mounted to the teething member 118 . [0050] The pacifier 112 may include at least one alignment recess 138 formed in the front surface 130 of the face shield 116 . The alignment recesses 138 may be used to align the pacifier 112 with features of the mold 14 as will be described in further detail below. Other alignment features besides recesses may be used in place of the alignment recesses 138 including, for example, projections, clips, or interference fits that provide at least one of alignment and connection of the pacifier relative to the mold. [0051] Referring now to FIG. 11 , the mold 14 includes a base 70 , a plurality of mold cavities 72 , 73 , a plurality of mold sidewalls 74 , and a plurality of pacifier interfaces 76 . The mold cavities 72 , 73 may be configured to receive a liquid 78 that at least partially fills the mold cavities 72 , 73 . Portions of the pacifiers 12 , 112 (e.g., the teething member 18 , 118 ) are inserted into the mold cavities 72 , 73 , respectively. The pacifiers 12 , 112 contact the pacifier interface 76 to support the pacifiers 12 , 112 while the liquid 78 is frozen to form the frozen members 22 , 122 . The pacifier interface 76 may be defined at least in part by an uppermost surface of the mold sidewalls 74 adjacent to openings into the mold cavities 72 , 73 . In other arrangements, the pacifier interface 76 may be positioned at other locations along the mold sidewall 74 or within the mold cavities 72 , 73 . [0052] The pacifier interface 76 , alone or in combination with, for example, the alignment recesses 138 or other alignment features on the pacifiers 12 , 112 , may align the teething members 18 , 118 within the mold cavities 72 , 73 while the liquid 78 is being frozen. The pacifier interface 76 may also provide a releasable connection between the pacifiers 12 , 112 and the mold 14 . This releasable connection may provide a sealed connection that inhibits leakage of the liquid 78 after the pacifier system 10 is assembled and prior to the liquid 78 being frozen. Numerous types of alignment and securing features may be used at an interface between the pacifiers 12 , 112 and the mold 14 . [0053] The liquid 78 may comprise any desired ingredient. In one example, the liquid 78 is filtered water. In other examples, the liquid 78 comprises juice, electrolytes, medications, or nutritional supplements. The liquid 78 may comprise a gel, semi-liquid or semi-solid material. The liquid 78 may be pre-cooled or at least partially frozen prior to insertion of the teething members 18 , 118 into the mold cavities 72 , 73 . The liquid 78 may be frozen using any desired method such as, for example, exposure to temperatures of a standard freezer, or application of a super-cooled liquid such as liquid Nitrogen. [0054] The mold cavities 72 , 73 may, in one example, have a volume of about 5 mL to about 20 mL, and more preferably in the range of about 10 mL to about 15 mL of liquid. The amount of liquid held in the mold cavities 72 , 73 may vary depending on, for example, the size of the teething member 18 , 118 to be inserted therein, which displaces the liquid 78 within the mold cavity. [0055] The mold cavities 72 may have a taper shape with a taper angle α 2 . The taper angle α 2 may be in the range of, for example, about 2° to about 20°, and more preferable in the range of about 2° to about 10°. The tapered shape of the mold cavities 72 may promote easy removal of the frozen pacifier 13 from the mold 14 . [0056] Various materials, such as polymer-based materials, are possible for use in the pacifier system 10 . In one example, at least the teething member 18 comprises a silicon material such as, for example, a 45 durometer food grade silicon. An example of such silicon material is the QM245 silicon material sold by Quantum Silicon of Richmond, Va. Other portions of the pacifier 12 such as the face shield 16 and handle 20 may comprise such silicon material. Other types of silicon such as medical grade silicon may be used in portions of the pacifier that do not interface with the mouth or face of the child. The mold 14 may also comprise silicon materials or other polymer materials that are easily cast or molded into the shape of mold 14 . According to one exemplary embodiment, the mold 14 may be manufactured from a FDA approved food grade material, one example of which is 245. [0057] According to one exemplary embodiment, the pacifier system 10 may be manufactured from a medical grade and FDA approved food grade silicone/polymer due to its contact with the mouth. Exemplary medical grade and FDA approved food grade silicone/polymers include, but are in no way limited to, MED-6382 silicone elastomer and MED-6010 silicone elastomer. [0058] In at least one example, the mold 14 comprises materials that provide flexibility of the mold cavities 72 , 73 . FIG. 11 shows the mold cavity 73 being expandable radially outward in the direction R to increase a size of the opening into the mold cavity 73 . This elastic deformation of the mold cavity 73 may promote removal of the frozen member when the frozen member has a negative angled shape (e.g., the bulbous shape of mold cavity 73 having a width W 5 that is greater than an inlet width W 4 of the opening into the mold cavity 73 ). [0059] Another aspect of the present disclosure relates to providing a packet of frozen pacifiers that includes at least one frozen pacifier positioned within an enclosed packaging such as a disposable plastic package. The packaging may be sized to hold a plurality of frozen pacifiers. A plurality of individually packaged frozen pacifiers may be held within a greater sized package. In other arrangements, a pacifier system includes a plurality of pacifiers and at least one mold packaged together as a kit. The purchaser may form their own frozen pacifiers by filling the mold cavities of the mold with a liquid, inserting the teething member of the pacifier into the mold cavity, and freezing the liquid to form a frozen pacifier having a frozen member mounted to the teething member of the pacifier. [0060] An example method of forming a frozen pacifier using the pacifier system 10 may include at least partially filling the mold cavity 72 with a liquid 78 , inserting the teething member 18 into the mold cavity in contact with the liquid 78 , freezing the liquid 78 to form a frozen member 22 , and removing the pacifier 12 with frozen member 22 from the mold cavity 72 with the frozen member 22 connected to the teething member 18 . The frozen member 22 may then be used to treat a child (e.g., inserting the frozen member 22 into the child's mouth). The child may chew on the teething member 18 after removal of the frozen member 22 (e.g., by melting the frozen member 22 within the child's mouth). [0061] The method may include deforming a portion of the mold to remove the frozen member 22 from the mold. The method may include providing the pacifier with a face shield and handle in addition to the teething member. The face shield may have a contoured surface. The teething member may include a plurality of projections for recesses on an outer surface thereof that enhance its function as a teething member and provide connection of the frozen member 22 to the teething member 18 . The handle 20 may include a loop structure having a handle opening. [0062] The preceding description has been presented only to illustrate and describe exemplary embodiments of the system and process. It is not intended to be exhaustive or to limit the system and process to any precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the system and process be defined by the following claims.
A pacifier system includes a pacifier having a face shield, a teething member, and a handle. The face shield includes first and second sides. The first side has a concave surface. The teething member extends from the concave surface on the first side of the face shield. The handle extends from the second side of the face shield. The pacifier system also includes a frozen member mold having a cavity that is sized to hold a volume of frozen fluid and receives the teething member held within the frozen fluid. The teething member is configured to maintain connection with the frozen fluid. The pacifier is removable from the frozen member mold with the frozen fluid attached to the teething member. The frozen fluid is insertable into a child's mouth to pacify the child and the teething member is configured to be chewed after the frozen fluid is removed.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "TECHNICAL FIELD [0001] The present systems and methods relate to pacifiers and teethers.", "More particularly, present systems and methods relate to pacifiers and teethers having a frozen portion.", "CROSS RELATED APPLICATIONS [0002] This application is a divisional of U.S. patent application Ser.", "No. 13/527,135 filed on 19 Jun. 2012 and titled Frozen Pacifier and Teether.", "U.S. patent application Ser.", "No. 13/527,135 is herein incorporated by reference for all that it teaches.", "BACKGROUND [0003] Pacifiers have been used for many years to help sooth or pacify a baby.", "Some types of pacifiers include a pacifying nipple and a teething ring positioned opposite the nipple to provide both pacifying and teething functions for the baby.", "Pacifier nipples are typically hollow and hold a sealed volume of air.", "[0004] Some teething rings hold fluid or comprise materials that retain cold temperatures when stored in a cold environment.", "The cold teething ring may provide additional comfort for a baby with swollen gums when teething.", "[0005] Babies and small children are sometimes prone to receive facial injuries that result from, for example, learning to crawl or walk.", "Injuries to a baby's mouth can be particularly difficult to treat with cold compresses or ice because the child is uncooperative and does not understand the benefit of such treatment.", "[0006] Further, a number of problems exist related to giving medication or fluids to a child orally.", "Some babies and small children are very resistant to other people putting things into their mouth, even when such things are intended for the child's improved health or care.", "[0007] There is a need for improvements in treating oral injuries in children and oral delivery of medications and fluids to children that is convenient and easy to use.", "SUMMARY [0008] One aspect of the present disclosure relates to a pacifier system that includes a pacifier and a frozen member mold.", "The pacifier includes a face shield, a teething member, and a handle.", "The face shield includes a first side and a second side, wherein the first side has a concave surface.", "The teething member extends from the concave surface on the first side of the face shield.", "The handle extends from the second side of the face shield.", "The frozen member mold includes a cavity that is sized to hold a volume of frozen fluid and receives the teething member held within the frozen fluid.", "The teething member is configured to maintain a connection with the frozen fluid.", "The pacifier is removable from the frozen member mold with the frozen fluid attached to the teething member.", "The frozen fluid is insertable into a child's mouth to pacify the child and the teething member is configured to be chewed after the frozen fluid is removed.", "[0009] The teething member may include a plurality of protrusions on an exterior surface thereof.", "The frozen fluid may have a tapered shape.", "The cavity may have a nipple shape.", "The handle may comprise a loop-shaped portion.", "The face shield may be configured to contact an outer facial surface of the child when the frozen fluid is inserted into the child's mouth.", "The frozen member mold may include a plurality of cavities and a plurality of pacifier interfaces.", "The teething member may include a food grade silicone.", "The cavity may have a bulbous shape.", "The frozen member mold may include a pacifier interface configured to support the pacifier and orient the teething member within the cavity.", "[0010] Another aspect of the present disclosure relates to a pacifier that includes a face shield, a teething member, a handle, and a frozen fluid.", "The face shield may include a first side and a second side, wherein the first side is configured to contact lips or a facial surface of a child adjacent to a mouth of the child.", "The teething member extends from the first side of the face shield and has an exterior surface.", "The handle extends from the second side of the face shield and includes a grasping portion.", "The frozen fluid is mounted to the exterior surface of the teething member and has a nipple shape.", "The teething member includes a structure that retains the frozen fluid on the outer surface of the teething member.", "[0011] The teething member may include a plurality of protrusions formed on the exterior surface thereof.", "The frozen fluid may include at least one of a medication, a flavor, a color, water and a juice.", "The teething member may include silicone.", "The first side of the face shield may include a concave surface and a plurality of holes formed in the concave surface.", "The pacifier may be integrally formed as a single piece.", "[0012] A further aspect of the present disclosure relates to a method of manufacturing a frozen pacifier.", "The method includes forming a pacifier that includes a face shield, a teething member extending from a first side of the face shield, and a handle extending from a second side of the face shield.", "The method may also include forming a mold comprising a mold cavity, wherein the mold cavity is configured to be filled with a liquid and to receive the teething member.", "A liquid in the mold cavity is frozen to form a frozen liquid that is secured to the teething member.", "The frozen liquid is removed from the mold cavity while secured to the teething member and configured for insertion into a child's mouth.", "The teething member is configured to be chewed within the child's mouth after the frozen liquid is removed from the teething member.", "[0013] The method may include releasably connecting the pacifier to the mold while freezing the liquid.", "The method may include integrally forming the pacifier as a single piece.", "The method may include forming the frozen liquid with a bulbous shape.", "[0014] Another example method in accordance with the present disclosure relates to a method of using a pacifier system.", "The method includes providing a pacifier and a mold, wherein the pacifier includes a face shield, a teething member extending from a first side of the face shield, and a handle extending from a second side of the face shield.", "The mold includes a mold cavity having a nipple shape that is sized to fit within a child's mouth.", "The method may also include filling the mold cavity with a liquid, inserting a teething member into the mold cavity, freezing the liquid into a frozen liquid that is secured to the teething member, removing the teething member with the frozen liquid from the mold cavity, inserting the frozen liquid into the child's mouth to treat the child's mouth, removing the frozen liquid, and chewing on the teething member with the child's mouth after removing the frozen liquid.", "Removing the frozen liquid may include thawing the frozen liquid in the child's mouth.", "BRIEF DESCRIPTION OF THE DRAWINGS [0015] The accompanying drawings illustrate various embodiments of the principles described herein and are a part of the specification.", "The illustrated embodiments are merely examples and do not limit the scope of the claims.", "[0016] FIG. 1 is a perspective view of an example pacifier system in accordance with the present disclosure.", "[0017] FIG. 2 is a perspective view of a pacifier of the pacifier system of FIG. 1 .", "[0018] FIG. 3 is a perspective view of the pacifier of FIGS. 1 and 2 with a frozen member mounted thereon.", "[0019] FIG. 4 is a front view of the pacifier of FIG. 2 .", "[0020] FIG. 5 is a rear view of the pacifier of FIG. 2 .", "[0021] FIG. 6 is a cross-sectional view of the pacifier of FIG. 4 .", "[0022] FIG. 7 is a front view of the pacifier with the frozen member of FIG. 3 .", "[0023] FIG. 8 is a cross-sectional view of the pacifier and the frozen member of FIG. 7 .", "[0024] FIG. 9 is a front view of another example pacifier with the frozen member in accordance with the present disclosure.", "[0025] FIG. 10 is a cross-sectional view of the pacifier and the frozen member of FIG. 9 .", "[0026] FIG. 11 is a cross-sectional view of the pacifier system of FIG. 1 and the pacifier of FIG. 9 .", "[0027] Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.", "DETAILED DESCRIPTION [0028] The present disclosure relates to pacifiers, teethers, pacifiers having teething features, pacifiers with frozen members mounted thereon, molds used for frozen pacifiers, pacifier systems that include pacifiers and molds, and related methods.", "One aspect of the present disclosure relates to systems and methods for forming a frozen pacifier, or at least a pacifier having a frozen portion mounted on the exterior surface thereof.", "The frozen portion may comprise a liquid such as water, juice, or hydrating material that is solidified into a size and shape that fits within a child's mouth.", "A portion of the pacifier to which the frozen member is mounted on an exterior surface thereof may be configured as a teething member that the child can chew upon after the frozen member has been removed (e.g., by thawing within the child's mouth).", "[0029] The frozen pacifier and related pacifier system and methods disclosed herein may have certain advantages over other types of pacifiers and teething structures.", "The frozen pacifiers of the present disclosure incorporate a pacifier construction that is visually identified by a child as an object that provides comfort that will soothe the child.", "The pacifier is provided with a teething portion so that the child may chew upon the teething portion to encourage teething in the child's mouth.", "The teething member may be exposed after the frozen member is removed from the pacifier.", "The teething member may provide a substrate or structure upon which the frozen member is connected to the pacifier.", "In one example, the teething member includes a plurality of protrusions, dimples, shapes and sizes that promote insertion of the teething member into a child's mouth and encourage chewing on the teething member by the child.", "The structure and features on an exterior surface of the teething member may also promote connection of the frozen member to the pacifier.", "[0030] The frozen member may have a shape and size similar to the nipple of a typical pacifier.", "In one example, the frozen member has a bulbous shape.", "Other examples include a cylindrical shape with a rounded end portion and a slightly tapered sidewall.", "The frozen member typically has a length that provides comfortable insertion into a child's mouth until a face shield portion of the pacifier contacts the lips and other facial tissues surrounding the mouth of the child.", "The frozen member may be sized for different aged children such as, for example, an infant (ages 0-12 months), a toddler (ages 1-3 years), and an older child (ages 4-8 years).", "[0031] An example pacifier system may include a mold used to form the frozen member onto the teething member of the pacifier.", "The mold may include a plurality of cavities.", "The cavities may have different shapes and sizes to provide frozen members of different shapes and sizes.", "[0032] The frozen member may be used to hydrate a child that otherwise cannot or will not drink or ingest fluids.", "The shape and appearance of the frozen member in combination with the pacifier features of a face shield and handle may promote acceptance and use of the frozen pacifier by the child, which results in intake of liquids as the frozen member is thawed in the child's mouth.", "The frozen member may provide a mechanism for delivery of a medication to the child.", "The frozen member may include flavors, colors, aromas, and other characteristics that promote use by the child.", "[0033] The frozen member may also be used for treating a child that would not otherwise permit contact of a frozen object (e.g., an ice cube or ice pack) in close proximity to the child's mouth.", "For example, the frozen member may be used as an ice compact for a child that has received a mouth injury such as an injury to lips, gums, tongue, teeth, or palate of the child.", "The frozen member can be applied to the injured tissue by the child or by an adult either on an exterior facial surface of the child (e.g., on lips or facial tissues surrounding the mouth) or within the child's mouth (e.g., gums, tongue or palate).", "The frozen member may be shaped with contoured surfaces that provide comfortable, smooth motion over the child's facial tissue.", "The nipple shape of the frozen member may also induce sucking on the frozen member by the child.", "[0034] Referring now to FIGS. 1-8 , an example pacifier system 10 is shown including a pacifier 12 and a mold 14 .", "The pacifier system 10 may include a plurality of pacifiers 12 of different shapes and sizes.", "The mold 14 may include a plurality of cavities each sized to receive a different one of the pacifiers.", "The cavities may have different shapes and sizes to provide various shaped and sized frozen members attached to the pacifier.", "Typically, the cavities of the mold 14 are at least partially filled with a fluid.", "A portion of the pacifiers 12 are inserted into the cavities of the mold into contact with the fluid.", "The pacifier system 10 is then placed in a cold environment such as a freezer wherein the liquid is frozen to form a frozen member that is attached to the pacifiers.", "The pacifiers 12 with frozen members 22 are removed from the cavities of mold 14 to provide a frozen pacifier 13 as shown in FIG. 1 .", "[0035] The pacifier 12 includes a face shield 16 , a teething member 18 , and a handle 20 .", "The face shield includes front and rear surfaces 30 , 32 .", "The teething member 18 extends from the front surface 30 and the handle 20 extends from the rear surface 32 .", "The front surface 30 may be curved or contoured, and may have a concave shape (see FIG. 6 ).", "The curvature of the front surface 30 may match a typical curvature of a child's face in the area around a mouth of the child.", "[0036] The face shield 16 may also include a top edge 34 and a bottom edge 36 .", "The top edge 34 may include a recess 35 in the area where the top edge 34 typically would otherwise contact a nose of the child (see FIG. 4 ).", "The face shield 16 may have a width W 1 and a height H as shown in FIG. 4 .", "The width W 1 may be greater than the height H. The width W 1 of the face shield is typically in the range of about 1 inch to about 3 inches, and more preferably about 2 inches.", "The height H is typically in the range of about 1 inch to about 2 inches, and more preferably in the range of about 1.25 to about 1.5 inches.", "[0037] The teething member 18 may include proximal and distal ends 40 , 42 , side and end surfaces 44 , 46 , and a plurality of projections 48 formed on the side and end surfaces 44 , 46 (see FIGS. 4 and 6 ).", "In some arrangements, at least some of the projections 48 may be replaced by a plurality of recesses such as dimples.", "The side surface 44 is shown in FIG. 6 being relatively straight and extending perpendicular from the front surface 30 of the face shield 16 .", "In other examples, the teething member 18 may have different shapes and sizes such as a bulbous shape, a tapered shape, a spherical shape, etc.", "[0038] The teething member 18 may extend a length L 1 from the front surface 30 to face shield 16 .", "Typically, the length L 1 is selected to be adequate for use with children having a range of mouth sizes (e.g., infants, toddlers, or older children).", "The length L 1 is typically no greater than a depth of a mouth cavity of the child so that the teething member 18 does not create a choking hazard for the child.", "The length L 1 of the teething member 18 is typically in the range of about 0.5 inch to about 1.5 inches, and more preferably in the range of about 1 inch to about 1.5 inches.", "[0039] The teething member 18 may have a width W 2 that permits insertion into the child's mouth.", "The width W 2 (see FIG. 4 ) is typically in the range of about 0.25 inches to about 0.75 inches, and more preferably in the range of about 0.5 inches to about 0.625 inches.", "[0040] The projections 48 or other surface features on the side and end surfaces 44 , 46 may promote chewing of the teething member 18 by the child.", "Chewing on the teething member 18 may be desirable for children who are trying to cut teeth through their gums.", "Chewing on the teething member 18 may help wear through the gum tissue so that the cutting teeth are exposed.", "The surface features of the teething member 18 may be configured (e.g., sized, shaped, and arranged) to make the teething member 18 more desirable for a child to insert into its mouth and chew upon.", "[0041] The handle 20 may include a handle opening 50 and a handle connection portion 52 .", "The handle opening 50 may create a loop structure in the handle 20 so that the handle 20 is easier to grasp for purposes of carrying or maneuvering the pacifier 12 .", "The handle connection portion 52 may be secured to the rear surface 32 of the face shield 16 .", "In some arrangements, the handle 20 is connected directly to the teething member 18 and may be integrally formed with the teething member 18 .", "The face shield may be separately attached to one of the handle 20 and teething member 18 .", "[0042] In at least some arrangements, the entire pacifier 12 may be integrally formed as a single piece as shown in FIG. 6 .", "In other arrangements, portions of the pacifier 12 may be formed separate from the other portions and later assembled during manufacturing.", "For example, the handle 20 may be formed separate from the face shield 16 and teething member 18 and connected in a later assembly step using a connection method such as, for example, an adhesive, heat welding, or a snap-fit connection.", "[0043] Referring now to FIGS. 7 and 8 , an example frozen pacifier 13 is shown including the pacifier 12 and an additional frozen member 22 mounted thereto.", "The frozen member 22 includes proximal and distal ends 60 , 62 , side and end surfaces 64 , 66 , a length L 2 , and a maximum width W 3 .", "The length L 2 is typically no greater than a depth of a mouth cavity of the child so that the frozen member 22 does not create a choking hazard for the child.", "The length L 2 of the frozen member 22 is typically in the range of about 1 inch to about 2.5 inches, and more preferably in the range of about 1 inch to about 2 inches.", "The frozen member 22 may have a maximum width W 3 that permits insertion into the child's mouth.", "The width W 3 (see FIG. 7 ) is typically in the range of about 0.5 inches to about 1.5 inches, and more preferably in the range of about 0.5 inches to about 1 inch.", "[0044] Typically, the length L 2 is greater than the length L 1 of the teething member 18 , and the width W 3 is greater than the width W 2 of the teething member 18 so that the entire teething member 18 is encapsulated within the frozen member 22 .", "Encapsulating the teething member 18 within the frozen member 22 may also provide improved connection between the frozen member 22 and the teething member 18 .", "In some arrangements, portions of the teething member 18 may be exposed outside of the frozen member 22 prior to using the frozen pacifier 13 with a child.", "[0045] The frozen member 22 may have a tapered construction with a taper angle α 1 .", "The taper angle α 1 may be in the range of, for example, about 2° to about 20°, and more preferable in the range of about 2° to about 10°.", "The tapered shape of the frozen member 22 may promote easy removal of the frozen pacifier 13 from the mold 14 .", "[0046] Many other shapes and sizes are possible for the frozen member 22 .", "In one example, the frozen member 22 has a bulbous shape as shown in, for example, FIGS. 9 and 10 .", "The frozen member 22 may have a negative taper angle with an increasing width towards the distal end 62 .", "The frozen member 22 may have contoured shapes and smooth surfaces to promote easy insertion into a child's mouth.", "Alternatively, the frozen member 22 may have a plurality of planar surfaces and angular shapes.", "The frozen member 22 may have a nipple shape such as a nipple shape of pacifiers typically sold in the industry.", "[0047] Although not shown, the frozen member 22 may have a plurality of projections, recesses, serrations, or divots formed in the side and end surfaces 64 , 66 .", "The surface features of the frozen member 22 may assist in treating or soothing a child by contacting exterior facial tissue or placing the frozen member 22 within the child's mouth.", "The surface features of the frozen member 22 may have aesthetic benefits such as, for example, making the frozen member 22 more attractive for a child to insert into its mouth.", "[0048] Referring now to FIGS. 9 and 10 , another example pacifier 112 is shown having a frozen member 122 mounted therein to form a frozen pacifier 113 .", "The pacifier 112 includes a face shield 116 , a teething member 118 , and a handle 120 .", "The face shield 116 includes front and rear surfaces 130 , 132 (see FIG. 10 ), with the teething member 118 extending from the front surface 130 and the handle 120 extending from the rear surface 132 .", "A plurality of holes 131 may be formed in the face shield 116 to permit air to pass from the front surface 130 to the rear surface 132 .", "The teething member 118 may include proximal and distal ends 140 , 142 , an end surface 146 , a bulb portion 147 at the distal end 142 , and a base portion 149 at the proximal end 140 .", "The base portion 149 connects the teething member 118 to the face shield 116 .", "The handle 120 includes a handle opening 150 and a handle connection portion 152 for connection of the handle 120 to the rear surface 132 of the face shield 116 .", "[0049] The frozen member 122 may include proximal and distal ends 160 , 162 , an end surface 166 , a bulb portion 167 , and a base portion 169 .", "The frozen member 122 may have a shape that corresponds to or mirrors the shape of the teething member 118 .", "In other arrangements, the teething member 118 and frozen member 122 may have different shapes.", "For example, the teething member 118 may have a generally cylindrical shape with a circular cross-section as shown in FIGS. 1-8 , and the frozen member 122 may have a generally bulbous shape as shown in FIGS. 9 and 10 .", "The bulbous shape of the teething member 118 may assist in retaining the frozen member 122 on an outer surface thereof.", "The teething member 118 may include other shapes, sizes, and surface features that assist in maintaining the frozen member 122 mounted to the teething member 118 .", "[0050] The pacifier 112 may include at least one alignment recess 138 formed in the front surface 130 of the face shield 116 .", "The alignment recesses 138 may be used to align the pacifier 112 with features of the mold 14 as will be described in further detail below.", "Other alignment features besides recesses may be used in place of the alignment recesses 138 including, for example, projections, clips, or interference fits that provide at least one of alignment and connection of the pacifier relative to the mold.", "[0051] Referring now to FIG. 11 , the mold 14 includes a base 70 , a plurality of mold cavities 72 , 73 , a plurality of mold sidewalls 74 , and a plurality of pacifier interfaces 76 .", "The mold cavities 72 , 73 may be configured to receive a liquid 78 that at least partially fills the mold cavities 72 , 73 .", "Portions of the pacifiers 12 , 112 (e.g., the teething member 18 , 118 ) are inserted into the mold cavities 72 , 73 , respectively.", "The pacifiers 12 , 112 contact the pacifier interface 76 to support the pacifiers 12 , 112 while the liquid 78 is frozen to form the frozen members 22 , 122 .", "The pacifier interface 76 may be defined at least in part by an uppermost surface of the mold sidewalls 74 adjacent to openings into the mold cavities 72 , 73 .", "In other arrangements, the pacifier interface 76 may be positioned at other locations along the mold sidewall 74 or within the mold cavities 72 , 73 .", "[0052] The pacifier interface 76 , alone or in combination with, for example, the alignment recesses 138 or other alignment features on the pacifiers 12 , 112 , may align the teething members 18 , 118 within the mold cavities 72 , 73 while the liquid 78 is being frozen.", "The pacifier interface 76 may also provide a releasable connection between the pacifiers 12 , 112 and the mold 14 .", "This releasable connection may provide a sealed connection that inhibits leakage of the liquid 78 after the pacifier system 10 is assembled and prior to the liquid 78 being frozen.", "Numerous types of alignment and securing features may be used at an interface between the pacifiers 12 , 112 and the mold 14 .", "[0053] The liquid 78 may comprise any desired ingredient.", "In one example, the liquid 78 is filtered water.", "In other examples, the liquid 78 comprises juice, electrolytes, medications, or nutritional supplements.", "The liquid 78 may comprise a gel, semi-liquid or semi-solid material.", "The liquid 78 may be pre-cooled or at least partially frozen prior to insertion of the teething members 18 , 118 into the mold cavities 72 , 73 .", "The liquid 78 may be frozen using any desired method such as, for example, exposure to temperatures of a standard freezer, or application of a super-cooled liquid such as liquid Nitrogen.", "[0054] The mold cavities 72 , 73 may, in one example, have a volume of about 5 mL to about 20 mL, and more preferably in the range of about 10 mL to about 15 mL of liquid.", "The amount of liquid held in the mold cavities 72 , 73 may vary depending on, for example, the size of the teething member 18 , 118 to be inserted therein, which displaces the liquid 78 within the mold cavity.", "[0055] The mold cavities 72 may have a taper shape with a taper angle α 2 .", "The taper angle α 2 may be in the range of, for example, about 2° to about 20°, and more preferable in the range of about 2° to about 10°.", "The tapered shape of the mold cavities 72 may promote easy removal of the frozen pacifier 13 from the mold 14 .", "[0056] Various materials, such as polymer-based materials, are possible for use in the pacifier system 10 .", "In one example, at least the teething member 18 comprises a silicon material such as, for example, a 45 durometer food grade silicon.", "An example of such silicon material is the QM245 silicon material sold by Quantum Silicon of Richmond, Va.", "Other portions of the pacifier 12 such as the face shield 16 and handle 20 may comprise such silicon material.", "Other types of silicon such as medical grade silicon may be used in portions of the pacifier that do not interface with the mouth or face of the child.", "The mold 14 may also comprise silicon materials or other polymer materials that are easily cast or molded into the shape of mold 14 .", "According to one exemplary embodiment, the mold 14 may be manufactured from a FDA approved food grade material, one example of which is 245.", "[0057] According to one exemplary embodiment, the pacifier system 10 may be manufactured from a medical grade and FDA approved food grade silicone/polymer due to its contact with the mouth.", "Exemplary medical grade and FDA approved food grade silicone/polymers include, but are in no way limited to, MED-6382 silicone elastomer and MED-6010 silicone elastomer.", "[0058] In at least one example, the mold 14 comprises materials that provide flexibility of the mold cavities 72 , 73 .", "FIG. 11 shows the mold cavity 73 being expandable radially outward in the direction R to increase a size of the opening into the mold cavity 73 .", "This elastic deformation of the mold cavity 73 may promote removal of the frozen member when the frozen member has a negative angled shape (e.g., the bulbous shape of mold cavity 73 having a width W 5 that is greater than an inlet width W 4 of the opening into the mold cavity 73 ).", "[0059] Another aspect of the present disclosure relates to providing a packet of frozen pacifiers that includes at least one frozen pacifier positioned within an enclosed packaging such as a disposable plastic package.", "The packaging may be sized to hold a plurality of frozen pacifiers.", "A plurality of individually packaged frozen pacifiers may be held within a greater sized package.", "In other arrangements, a pacifier system includes a plurality of pacifiers and at least one mold packaged together as a kit.", "The purchaser may form their own frozen pacifiers by filling the mold cavities of the mold with a liquid, inserting the teething member of the pacifier into the mold cavity, and freezing the liquid to form a frozen pacifier having a frozen member mounted to the teething member of the pacifier.", "[0060] An example method of forming a frozen pacifier using the pacifier system 10 may include at least partially filling the mold cavity 72 with a liquid 78 , inserting the teething member 18 into the mold cavity in contact with the liquid 78 , freezing the liquid 78 to form a frozen member 22 , and removing the pacifier 12 with frozen member 22 from the mold cavity 72 with the frozen member 22 connected to the teething member 18 .", "The frozen member 22 may then be used to treat a child (e.g., inserting the frozen member 22 into the child's mouth).", "The child may chew on the teething member 18 after removal of the frozen member 22 (e.g., by melting the frozen member 22 within the child's mouth).", "[0061] The method may include deforming a portion of the mold to remove the frozen member 22 from the mold.", "The method may include providing the pacifier with a face shield and handle in addition to the teething member.", "The face shield may have a contoured surface.", "The teething member may include a plurality of projections for recesses on an outer surface thereof that enhance its function as a teething member and provide connection of the frozen member 22 to the teething member 18 .", "The handle 20 may include a loop structure having a handle opening.", "[0062] The preceding description has been presented only to illustrate and describe exemplary embodiments of the system and process.", "It is not intended to be exhaustive or to limit the system and process to any precise form disclosed.", "Many modifications and variations are possible in light of the above teaching.", "It is intended that the scope of the system and process be defined by the following claims." ]
FIELD OF THE INVENTION The present invention relates to a method and apparatus for desorbing materials from a loaded ion exchange resin. The ion exchange resin may be any suitable resin that can be loaded with target materials that include non-ferrous metals such as copper, nickel and cobalt; noble metals such as gold and silver; and refractory metals such as molybdenum and wolfram. The exchange resin may also be suitable for any other metal, non-metal, organic substances, non-organic substances and compounds thereof. BACKGROUND OF THE INVENTION There is at present a wide selection of technology that can be used for desorbing materials from resins. Some technologies are better suited than others for particular applications and, therefore, selecting the most appropriate technology is an important factor in achieving a high desorption rate and cost effectiveness. Generally speaking desorption processes for desorbing material from a resin may be carried out as either batch or continuous operations which usually corresponds to the apparatuses for carrying out processes having either so-called fixed-beds or moving-beds. Apparatuses with fixed-beds are at present the most widely used in industry. For example, a text by Abrams I. M. entitled “Type of ion-exchange systems” (Ion Exchange for Pollution Control, eds. C. Calmon and H. Gold, CRC Press, Boca Raton, vol. 1, pp. 71-850, 1979) describes that fixed-bed equipment items have been operated for more than. 25 years and are still presently in use for softening 1500 mega-liters/day of water at the Metropolitan Water District of Southern California. A text by Salem E. entitled “Equipment operation and design” (Ion Exchange for Pollution Control, eds. C. Calmon and H. Gold, CRC Press, Boca Raton, vol. 1, pp. 87-100, 1979) describes that the desorption cycle of most fixed-bed apparatuses involves: firstly backwashing a bed of full loaded or saturated resin; settling the bed; feeding desorption solution through the bed; displacement of desorption solution (or slow rinse); and finally rinsing the resin before supplying a pregnant solution to the bed again. The backwashing stage removes suspended particles, which have accumulated within the resin bed and eliminates channels that, may have formed during the sorption stage. Backwashing also helps to break up agglomerates formed between suspended particles and the ion-exchange resin. The settling stage follows the backwashing stage and is important to avoid channeling of fluid through the bed. Desorption is accomplished by passing desorption solution through the bed to convert the resin to the desired form. After an adequate volume of desorption solution has made contact with the resin, displacement of desorption solution from the bed takes place. Rinsing of the resin with demineralised water is normally used to remove the last residues of desorption solution from the bed. Upon completion of the rinsing stage, the liquid phase containing targeted material to be sorbed into the resin during a sorption stage enters at the top of the column when the column is operated in co-current or at the bottom of the column when the column is operated in countercurrent. U.S. Pat. No. 4,412,866 describes a modification of a batch-fixed bed process and in particular relates to a simulated moving-bed in which separate zones are defined, each of which include one or more discrete vessels. The zones correspond to the functions of the process; typically sorption, displacement, desorption and rinsing. Booster pumps connected in series with the vessels maintain a desired pressure head for each zone. The functions of each zone are rotated in sequence, the sequence being timed in relation of the migration of the front between adjacent phases in the fluid loop circulating through the zones. Another type of absorption/desorption processes is a continuous process. Generally speaking an absorption/desorption process is classified as a continuous process when sorption, rinsing and desorption are conducted simultaneously and the product flow is uninterrupted. The use of a moving bed of resin allows one to obtain continuous operation and the main advantage is the high processing efficiency. As with batch processes, continuous processes can be operated as either co-current or countercurrent. Not all processes described as continuous are truly continuous processes. Truly continuous processes operate without interruption of either resin or liquid flows. Semicontinuous processes are often characterised by a short residence period in which ion-exchange absorption occurs (i.e. the service mode) followed by a period when the resin bed is moved (the moving mode). However, because the periods for both modes are very short, the processes virtually behave as a continuous one. More than a hundred semicontinuous processes are known, but only about six have any real industrial significance. To our understanding the widest known process of this type is the so-called Higgins Loop (and is described in the text by Higgins, I. R. and Roberts, I. T. “A countercurrent solid-liquid contactor for continuous ion-exchange”. Eng Prog. Symp. Ser., 50, 87-94, 1950). The Higgins Loop is a continuous countercurrent ion-exchange process for liquid phase separations of ionic components using solid ion-exchange resin. The Higgins Loop comprises a vertical cylindrical vessel containing a packed-bed of ion-exchange resin that is separated into four operating zones by butterfly or loop valves. These operating zones—adsorption, desorption, backwashing and pulsing—function like four separate vessels. The Higgins Loop treats liquids in the sorption zone with resin while the ions are removed from loaded resin in the desorption zone simultaneously. Intermittently, a small portion of resin is removed from the respective zone and replaced with stripped or loaded resin at the opposite end of that zone. This is accomplished hydraulically by pulsation of the resin through the loop. The result is a continuous process that contacts liquid and resin in countercurrent flow. It is an object of the present invention to provide an alternative method and apparatus for desorbing materials sorbed on a resin that is capable of producing a concentrated eluate stream. SUMMARY OF THE INVENTION According to the present invention there is provided an apparatus for desorbing substances from an ion exchange resin having impurities and targeted materials sorbed thereon, the apparatus including: first and second chambers that are adapted so that when in use, resin is supplied to the first chamber and conveyed from the first chamber to the second chamber, and a desorption solution is supplied to the second chamber and conveyed from the second chamber to the first chamber such that, i) impurities having less affinity for the resin than the targeted material can be desorbed from the resin and targeted material can be sorbed onto the resin from the desorption solution, and thereby create conditions whereby an impurity stream having a high concentration of impurities and a relatively low concentration of targeted material can be discharged from the first chamber, and ii) targeted material can be desorbed from the resin in the second chamber and create conditions whereby a rich stream having a low concentration of impurities and a relatively high concentration of targeted material can be discharged from lower regions of the first and/or second chambers. In addition, when the apparatus is in use, it is preferred that the resin flows downwardly in the first chamber and upwardly in the second chamber, and that desorption solution flows in countercurrent to the direction of flow of resin in said chambers. It is even more preferred that the impurities stream be discharged from an upper region of the first chamber. It is preferred that the first and second chambers be connected in fluid communication such that the desorption solution can be conveyed from the second chamber to the first chamber. According to the present invention there is also provided an apparatus for desorbing material from a loaded ion exchange resin, the apparatus including: first and second chambers that are adapted so that in use, resin can move downwardly in the first chamber and upwardly in the second chamber and desorption solution can flow in counter current to the resin; first and second inlets for supplying loaded resin to the first chamber and desorption solution to the second chamber respectively, and first and second outlets for discharging a liquid from the apparatus and stripped resin from the second chamber respectively; means for facilitating the transferal of resin from the first chamber to the second chamber and conveying the resin upwardly in the second chamber; and in use, a first stream of desorption solution containing a relatively high concentration of impurities and a low concentration of targeted materials can be discharged from the first outlet, a second stream of desorption solution containing a relatively high concentration of targeted material and a low concentration of impurities can be discharged via the first outlet from lower regions of the first and/or second chambers and/or taken from desorption solution passing from the second chamber to the first chamber, and a stripped resin can be discharged from the second outlet of the second chamber. Advantages provided by the present invention include: ii) impurities having less affinity for the resin than the targeted material are desorbed from the resin before the targeted material and thus the first stream of desorption solution has a higher concentration of impurities can be discharged from the first chamber where the desorption solution first comes into contact with the resin; iii) upon desorption of the impurities from the resin, the capacity of the resin to absorb targeted materials increases which allows the first chamber to have a zone for re-adsorbing targeted materials onto the resin; and iv) targeted materials desorbed from the resin passes into the desorption solution and thereby increases the density of the solution so that it tends to settle under gravity in the chambers and thus facilitate the second stream of desorption solution containing a relatively high concentration of targeted substances and a low concentration of impurities to be discharged from the lower region of the apparatus. It is preferred that the desorption of impurities from the resin occurs in an upper zone of the first chamber and thereby allows further targeted material to be sorbed onto the resin in the upper zone. In other words, the upper zone forms re-adsorption zone. It is preferred that the first and second chambers be connected in fluid communication such that the liquid head in the second chamber causes the desorption solution to flow upwardly in the first chamber. It will be appreciated that as a result of the desorption solution being supplied into the second chamber, the predominant direction of flow of desorption solution is from the second chamber into the first chamber. It will also be appreciated that the net upwardly flow of desorption solution in the first chamber will be substantially equal to the rate at which the first stream of desorption solution is discharged from the first chamber. It is preferred that the first outlet for discharging the first stream of desorption solution be in an upper region of the first chamber. An advantage provided by this preferred feature is that the desorption solution first comes into contact with the resin in the upper region of the first chamber and impurities having less affinity for the resin than the targeted material can be withdrawn from the upper end of the first chamber. It is preferred that the second outlet for discharging stripped resin be located in the upper region of the second chamber. An advantage provided by this preferred aspect is that the resin is progressively exposed to a desorption solution having lower concentrations of targeted materials as the resin moves upwardly in the second chamber and thereby creates a larger potential for desorption of targeted materials from the resin in the second chamber before the resin is discharged from the apparatus. It is preferred that a passageway extend downwardly from the second outlet for conveying stripped resin to an intermediate chamber before being discharged from the apparatus. It is preferred that the first and second inlets for supplying resin and desorption solution into the first and second chambers respectively be located in the upper region of the chambers. It is preferred that the apparatus have control means for controlling the rate of removal of resin from the second chamber. In use, the control means measures the liquid level of the desorption solution in the first chamber to control the rate at which resin is removed form the second chamber. It is preferred that the second chamber have another inlet for supplying a concentrated solution of targeted materials into the second chamber. We have found that adding a concentrated solution into the second chamber further increases the concentration of the targeted materials in the second stream of desorption solution (ie an eluate stream) and decreases the concentration of impurities in the second stream. The preferred features of two embodiments of the present invention will now be described. It is preferred that the first and second chambers be interconnected by a passageway that extends from the first chamber to the second chamber, the passageway being adapted for conveying the resin and desorption between the chambers. According to one embodiment of the invention, it is also preferred that the first and second chambers be interconnected in U-shape having a base and two arms whereby the first and second chambers form the arms of the U-shape and the base provide the passageway. It is preferred that the second stream of desorption solution containing a high concentration of desorbed material be discharged from the passageway extending between the first and second chambers. In the instance when the first and second chambers are interconnected in a U-shape, the second stream of desorption solution having a high concentration of targeted material is discharged from the base of the U-shape. According to another embodiment of the invention, it is the preferred that the first and second chambers be arranged such that one of the chambers is located inside the other chamber. It is even more preferred that the second chamber be located concentrically within the first chamber. In the instance when the second chamber is located within the first chamber, it is preferred that the first chamber have an opening facing downwardly so that desorption solution from the second chamber can flow into the second chamber and that the resin from the second chamber enter the first chamber through the opening and be forced to move upwardly therein. It is preferred the second stream of desorption solution be discharged from the first chamber at a location below the opening of the second chamber. It is preferred that a bottom wall of the first chamber be declined toward an outlet for discharging the second stream of desorption solution having a high concentration of targeted substances. According to the present invention there is provided a method for desorbing substances from an ion exchange resin having impurities and targeted materials sorbed thereon, the method including treating an ion exchange resin in an apparatus having first and second chambers, wherein the method includes the steps: a) desorbing impurities from the resin in the first chamber using a desorption solution so that targeted materials having more affinity for the resin than the impurities can be sorbed onto the resin from the desorption solution and thereby creating conditions whereby a stream having a high concentration of impurities and a low concentration of targeted material can be discharged from the first chamber; and b) desorbing targeted materials from the resin treated according to step a) in the second chamber using the desorption solution and thereby create conditions whereby a stream having a high concentration of targeted materials and a low concentration of the impurities can be discharged from the apparatus. According to the present invention there is also provided a method for desorbing substances from a resin in an apparatus having first and second chambers connected in fluid communication, the method including the steps of: a) supplying a loaded resin having targeted materials and impurities sorbed thereon to the first chamber and the resin moving in a downward direction therein; b) conveying the resin from the first chamber to the second chamber and moving the resin in an upward direction therein; c) supplying a desorption solution to the second chamber such that the solution flows downwardly in the second chamber and upwardly in the first chamber in countercurrent flow to the resin; d) discharging stripped resin from the second chamber; e) discharging a first stream of desorption solution containing a high concentration of impurities and a low concentration of targeted substances from the first chamber; and a) discharging a second stream of desorption solution containing a relatively high concentration of targeted material and a relatively low concentration of impurities from a lower region of the first and/or second chambers and/or from the solution being conveyed between the chambers. It is preferred that any two or more of steps a) to f) be carried out simultaneously. It is preferred that the impurities on the resin have less affinity for the resin than the targeted materials so that when the resin is contacted by the desorption solution in the first chamber, the impurities tend to be desorbed from the resin before desorption of the targeted materials. It is preferred that the desorption of impurities from the resin occurs in an upper zone of the first chamber and thereby allows further targeted material to be sorbed into the resin in the upper zone. It is therefore preferred that the first stream discharged in step e) be discharging the upper region of the first chamber. It is preferred that targeted materials desorbed from the resin and dissolved into solution increase the density of the solution thus causing fractions of the solution having high concentrations of targeted solutions to settle under gravity toward the lower regions of the first and second chambers. It is therefore preferred that the second stream discharged in step f) be discharged from the solution being conveyed between the chambers or from the lower regions of the first and/or second chambers. It is preferred that the rate, at which resin is discharged in step d), be controlled by the liquid level in the first chamber. It is preferred that the resin discharged in step d) be discharged from upper regions of the second chamber. It is preferred that the method also include supplying a concentrated solution of targeted substances into the second chamber. We have found that adding a solution of concentrated solution into the second chamber further increases the concentration of the targeted substances in the second stream of desorption solution (ie an eluate stream) and decreases the concentration of impurities in the second stream. It is preferred the temperature of the concentrated solution range from approximately 60 to 100° C. It is preferred that the additional solution be supplied into the second chamber at a location between the upper and lower regions of the second chamber. The method of the present invention may also include any one of the features of the apparatus described above. BRIEF DESCRIPTION OF THE DRAWINGS Two preferred embodiments of the present invention will now be described with reference to the accompanying drawings, of which: FIG. 1 illustrates an apparatus for desorbing material from a resin according to one embodiment of the invention, wherein the apparatus includes two chambers one chamber is located inside the other; FIGS. 2 and 3 illustrate the embodiment shown in FIG. 1 with additional features; FIG. 4 illustrates an apparatus for desorbing material according to an alternative embodiment, wherein the apparatus includes two chambers interconnected in a U-shape; and FIGS. 5 and 6 illustrate the embodiment shown in FIG. 4 with additional features. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The two preferred embodiments have a number of features in common and the same reference numerals have been used to identify the same or alike features on both embodiments where possible. The preferred embodiment illustrated in the FIG. 1 comprises an apparatus having two chambers in which an inner chamber 1 is located concentrically within the outer chamber 2 . The inner chamber 1 has an inlet valve 14 for supplying desorption solution to the inner chamber and an outlet for stripped resin. Extending from the outlet is a conduit that feeds stripped resin into an intermediate tank 7 . The lower end of the inner chamber 1 has an opening facing downwardly so that desorption solution flows downwardly in the inner 1 chamber and upwardly in the outer chamber 2 in the direction of the dashed arrows. The liquid head of desorption solution in the inner chamber 1 causes the desorption solution to flow upwardly in the outer chamber 2 . The outer chamber 2 has a resin inlet or spigot 5 for supplying saturated resin into the outer chamber 2 . Resin in the outer chamber 2 moves downwardly in the direction of the arrows shown in solid lines in countercurrent to the desorption solution. The resin is also forced through the opening in the inner chamber 1 and upwardly in the inner chamber 1 in the direction of the arrows shown in solid lines in countercurrent flow to the desorption solution. In use, loaded resin enters through the spigot 5 and contacts the loaded resin in the top of the outer chamber 2 . At first instance, impurities having less affinity for the resin than the targeted material are desorbed from the resin. As a result, a stream of desorption solution having a high concentration of impurities is discharged via outlet drain 3 . Upon desorption of the impurities form the resin, the capacity of the resin for sorbing targeted material may increase such that an upper region of the outer chamber 1 in which the impurities are desorbed may also form a re-adsorption zone for re-adsorbing the targeted material onto the resin. Normally, the re-adsorbing zone formed in the upper region of the first chamber 1 keeps the concentration of the targeted materials low in the stream of desorption solution discharged via the outlet drain 3 . The loaded resin migrates down past the re-adsorption zone and into the inner chamber 1 where targeted material is desorbed in a desorption zone of the apparatus. Resin moves along the inner and outer chambers 1 and 2 using any suitable means such as resin pulsation. In the case of the embodiment shown in FIGS. 1 to 3 , resin pulsation is carried out by opening valve 13 for discharging resin from apparatus, closing valve 14 so as interrupted the supply of desorption solution and pumping air into the column via the spigot 6 located on the top of the re-adsorption zone. Electrodes 9 and 10 , which measure the level of desorption solution in the outer chamber 2 of the apparatus control the rate at which resin is removed from the apparatus. Resin movement within the chambers 1 and 2 may take place periodically once every 0.5-3.0 hours and continue for about 0.5-2.0 minutes depending on the properties of the resin, the targeted material and the conditions of the desorption process. Desorption solution is pumped into the inner chamber 1 via the spigot 4 and the valve 14 . Desorption solution strips the target material from the oversaturated resin during its movement past desorption zone 1 downwardly to the bottom of the apparatus. A stream of desorption solution containing a high concentration of targeted material and a low concentration of the impurities is discharged from the bottom of the apparatus via the pipe 8 . The flow of solution from the bottom of the apparatus is regulated using valve 15 . A screen 11 at the bottom of the apparatus retains the resin in the outer chamber 2 as solution is discharged. FIGS. 2 and 3 illustrate the apparatus shown in FIG. 1 having an inlet 12 for supplying a concentrated solution of targeted materials into the middle of the inner chamber 1 . We have found that the addition of a concentrated solution to the inner chamber 1 reduces the concentration of impurities and increases the concentration of targeted material discharged from the apparatus through valve 15 . FIG. 3 illustrates the apparatus fitted with a heat exchange means for preheating the desorption solution supplied into the inner chamber 1 via inlet 12 and valve 14 for aiding the desorption of material from resin to the desorption solution. The desorption solution is preferably heated to a temperature ranging from 60° C. to 100° C. The apparatus is also includes external insulation for maintaining the temperature of the desorption solution in the chambers 1 and 2 . FIG. 4 illustrates an alternative embodiment in which the chambers 1 and 2 are interconnected in a U-shape. Specifically, chambers extend upwardly from opposite ends of a horizontal passageway that interconnects the chambers. The diameter of the passageway is substantially the same as the diameter of the chambers 1 and 2 such that the resin can be conveyed from chamber 2 to chamber 1 using the pulsation techniques described above. The passageway also provides fluid communication between the chambers 1 and 2 such that liquid head of desorption solution in chamber 1 causes desorption solution to flow upwardly in the outer chamber 2 . Moreover, the embodiment shown in FIGS. 4 to 6 includes the same features as the embodiment shown in FIGS. 1 to 3 and can be operated in the same manner. The same reference numerals have been used on both embodiments to show the same features. It is envisaged that the embodiments of the present invention can be operated so that the resin and desorption solution flow continuously and in countercurrent. However, it will appreciated by those skilled in the art that the flow of desorption solution and the movement of resin may be intermittent and in general terms, a continuous desorption process is one in which resin moves intermittently through a desorption apparatus. In particular, the movement of resin in a desorption apparatus normally involves an the resin being moved along the bed in intermitted increments whereby a slug of resin is discharged from an end of the bed and the rest of the resin moves in a direction along the bed. The present invention will now be described with reference to the following non-limiting examples. EXAMPLE 1 This example illustrates the desorption of copper from the resin that was saturated during the treatment of a waste-water steam of a copper electroplating plant. The example was carried out using the apparatus design as shown on FIG. 4 . The copper concentration in the rinse water was about 50-80 ppm and the resin loading capacity reached 28-32 g/l. The desorption trial was performed in a 150 L-plastic U-shape column in accordance with the embodiment shown in FIG. 4 . The loaded resin entered the column via the spigot 5 located on the lid of the column. After desorption the fully stripped resin was removed on an hourly basis from the column through the transfer pipe and the intermediate tank 7 . The resin passed through the column at a rate of 20 L/hr. A 7% solution of sulphuric acid was used as the desorption solution. A desorption stream was pumped at a rate of about 22 L/hr into the top of the desorption zone of the column via the spigot 4 with valve 14 in the open position. A waste stream was removed via the drainage 3 at the rate of 11.51/hr-12.51/hr. The copper concentration in the waste stream was less than 200 ppm and was returned together with the rinse water to the sorption stage. An eluate stream was collected from the bottom of the column through screen 11 and pipe 8 . The eluate solution was discharged at a rate of 9.5-10.51/hr using valve 15 . The copper concentration reached 60 g/l in the eluate stream, very near to the maximum of the solubility of the copper sulphate (CuSO 4 .5H 2 O) (bluestone). The eluate stream is analytically and economically suitable for the direct copper recovery using the well-known methods such as copper electrowinning or cupric sulphate precipitation. It is envisaged that an eluate stream formed by the above example can be used directly in a copper-electroplating bath and the waste rinse water containing copper can be returned to the production circuit a copper electroplating plant. It is also envisaged that the treated water may be returned to a water system of the copper electroplating plant. EXAMPLE 2 This example illustrates desorption of nickel from the resin, which was loaded during the sorption recovery of nickel from high-pressure laterite leach slurry. The example was carried out using the apparatus shown in FIG. 4 . Elemental analysis for the loaded resin is shown in Table 2.1. The desorption equipment consisted of a U-shape plastic laboratory column with volume 750 ml. The resin flowed through the column at a rate of 100 ml/hr. A 10% solution of hydrochloric acid was used as a desorption liquor. The solution was pumped into the column via the spigot 4 and the valve 14 and flowed through the desorption and re-absorption zones at rate about 160 ml/hr. The flow of the desorption solution was divided to two unequal parts: i) The waste solution stream, which was collected after desorption from the drainage 3 at volume about 100 ml/hr and input to the sorption stage together with the pregnant leach slurry. ii) The resulting eluate stream, which was collected from the bottom of the column via the pipe 15 and the opened partly valve 8 at volume 60 ml/hr. Elemental analysis for the eluate and waste streams are set out below in Table 2.1. TABLE 2.1 Results of the elemental analysis of the starting and resulting products. Loaded resin, Eluate stream Waste stream, Elements g/l ppm ppm Ni 36.81 59 510   382    Co  1.65 1 460   493    Mn  2.16 701 2 750    Mg  3.40  72 2 560    Fe  0.18 127 <0.001 Cu  0.27  69 0.08 Zn  0.22 141 86    Ca  0.35 103 396    Si  0.02  30 0.24 Cr  0.01    1.34 0.65 Al  0.24 123 6.05 These results of the example show that the concentration of nickel in the eluate was about 60 g/l, which we estimate to be approximately 60% greater than the loading capacity of the pregnant resin. It is also noted that the majority of impurities, for example magnesium and manganese were discharged in the waste solution discharged via outlet 3 and as a result, the high concentrated eluate is suitable for nickel electrowinning recovery. EXAMPLE 3 This example illustrates desorption of copper from a saturated resin, which was previously loaded during the sorption copper recovery from the heap leaching liquor. The copper concentration was between 2 g/l to 6 g/l. The loading capacity of the resin, involved in this copper trial, was 55-64 g/l. During this test the resin flowed through the desorption column at a rate of approximately 100 ml/hr. The desorption trial was performed in a 750 ml borosilicate glass column in accordance with the apparatus shown in FIG. 6 . The U-shape column was fully insulated to keep the temperature within the column between 60-70° C. A 10% solution of sulphuric acid was used as a desorbent, which was preheated up to 60-70° C. using an electric heater, on the inlet 4 of the desorption solution. The flow of the desorbent was maintained at rate of about 75 ml/hr In addition, a preheated mother liquor, after the precipitation of the copper sulphate, was pumped into the middle of chamber 1 through the inlet tube 12 with a throughput of about 85 ml/hr. In this mother liquor, the copper concentration was about 45 g/l. A waste stream was removed from chamber 2 through the drainage 3 at rate of ˜60 ml/hr and the copper concentration was less than 100 ppm. This waste solution may be reused in the copper heap leaching process. A saturated eluate stream was collected from the bottom of the apparatus via the pipe 8 and the adjusting valve 15 at a rate of 100 ml/hr, with a copper concentration of about 100 g/l and temperature ˜65° C. The eluate stream was cooled to 20° C. with continuous mixing and approximately 234 g of the copper sulphate crystals were precipitated from every liter of the eluate stream. After filtration of the copper sulphate crystals, the mother liquor with the copper concentration about 45 g/l was heated to ˜70° C. and reused to supply inlet tube 12 . EXAMPLE 4 This example illustrates the desorption of molybdenum from a loaded resin that was saturated during adsorption from molybdenum-containing solutions. The molybdenum concentration of these solutions was ˜1 g/l, so the equilibrium loading capacity of the resin was about 100 g/l. A desorption trail was performed in a 30 L column in accordance with the apparatus shown in FIG. 1 . The loaded resin was placed into the outer chamber 2 of the column via the spigot 5 . During this trail the resin flow was maintained at rate of ˜3 l/hr. A 10% ammoniac solution was used as a desorbent. This solution was pumped into the inner chamber 1 of the column via the spigot 4 with valve 14 in the open position. The throughout was kept 4 l/hr. A waste solution stream with a molybdenum concentration of less than 200 ppm was collected from drainage 3 at rate of about 2 l/hr and returned with the pregnant solution on the sorption stage. A saturated eluate stream was collected from the bottom of the column through the screen 11 and the pipe 8 . The volume of the removed eluate was regulated using the valve 15 . The molybdenum concentration of the eluate stream was ˜150 g/l and the main impurities concentrations were negligible. The solution is suitable for the economical recovery of the chemical grade ammonium paramolibdate. EXAMPLE 5 This example illustrates a method of nickel desorption from a saturated resin with the nickel loading capacity of about 42 g/l. The resin was loaded during the sorption nickel recovery from the atmospheric leach laterite slurry. A desorption equipment consisted of a 750 ml column in accordance with the embodiment shown in FIG. 3 . The loaded resin was placed into the column through the spigot 5 . The resin flow during this test was kept at rate of ˜100 ml/hr. A 10% solution of sulphuric acid was used as the desorption solution. The throughout of the desorbent was regulated by the peristaltic pump and maintained at rate of ˜75 ml/hr. The desorbent was pumped into the top of the desorption zone of the column via the spigot 4 and the valve 14 . The solution after the nickel electrowinning process contained 43 g/l and was pumped into the middle of the desorption zone of the column at rate of ˜85 ml/hr through the drainage 12 . A waste solution stream (about 60 ml/hr) was removed from the column via the drainage 3 . This solution contains about 200 ppm of nickel may be reused in the leaching process. An eluate stream was collected from the bottom of the column through the valve 15 and the pipe 8 at rate of about 100 ml/hr and contained about 85 g/l of nickel. This solution may be used for the nickel electrowinning.
The present invention relates to a method and apparatus for the continuous countercurrent desorption of targeted materials including metals, non-metals and inorganic and/or organic compounds of thereof, wherein the desorption method is divided to the two modes namely: (I) desorption and (II) re-absorption. The desorption of the target material from the loaded resin using the fresh desorbent takes place in mode (I). According to mode (I) loaded resin moves upwardly in a chamber. According to mode (II) impurities are desorbed from resin and targeted material in solution can be re-absorbed. The resin moves downwardly in another chamber during mode (II). Concentrated eluates, which are suitable for the direct economical recovery of chemical elements and/or compounds thereof, can be produced using the present invention. The apparatus of the present invention includes desorption and re-absorption zones that are configured using a “pipe-in-pipe” construction or a U-shape construction.
Summarize the information, clearly outlining the challenges and proposed solutions.
[ "FIELD OF THE INVENTION The present invention relates to a method and apparatus for desorbing materials from a loaded ion exchange resin.", "The ion exchange resin may be any suitable resin that can be loaded with target materials that include non-ferrous metals such as copper, nickel and cobalt;", "noble metals such as gold and silver;", "and refractory metals such as molybdenum and wolfram.", "The exchange resin may also be suitable for any other metal, non-metal, organic substances, non-organic substances and compounds thereof.", "BACKGROUND OF THE INVENTION There is at present a wide selection of technology that can be used for desorbing materials from resins.", "Some technologies are better suited than others for particular applications and, therefore, selecting the most appropriate technology is an important factor in achieving a high desorption rate and cost effectiveness.", "Generally speaking desorption processes for desorbing material from a resin may be carried out as either batch or continuous operations which usually corresponds to the apparatuses for carrying out processes having either so-called fixed-beds or moving-beds.", "Apparatuses with fixed-beds are at present the most widely used in industry.", "For example, a text by Abrams I. M. entitled “Type of ion-exchange systems”", "(Ion Exchange for Pollution Control, eds.", "C. Calmon and H. Gold, CRC Press, Boca Raton, vol.", "1, pp. 71-850, 1979) describes that fixed-bed equipment items have been operated for more than.", "25 years and are still presently in use for softening 1500 mega-liters/day of water at the Metropolitan Water District of Southern California.", "A text by Salem E. entitled “Equipment operation and design”", "(Ion Exchange for Pollution Control, eds.", "C. Calmon and H. Gold, CRC Press, Boca Raton, vol.", "1, pp. 87-100, 1979) describes that the desorption cycle of most fixed-bed apparatuses involves: firstly backwashing a bed of full loaded or saturated resin;", "settling the bed;", "feeding desorption solution through the bed;", "displacement of desorption solution (or slow rinse);", "and finally rinsing the resin before supplying a pregnant solution to the bed again.", "The backwashing stage removes suspended particles, which have accumulated within the resin bed and eliminates channels that, may have formed during the sorption stage.", "Backwashing also helps to break up agglomerates formed between suspended particles and the ion-exchange resin.", "The settling stage follows the backwashing stage and is important to avoid channeling of fluid through the bed.", "Desorption is accomplished by passing desorption solution through the bed to convert the resin to the desired form.", "After an adequate volume of desorption solution has made contact with the resin, displacement of desorption solution from the bed takes place.", "Rinsing of the resin with demineralised water is normally used to remove the last residues of desorption solution from the bed.", "Upon completion of the rinsing stage, the liquid phase containing targeted material to be sorbed into the resin during a sorption stage enters at the top of the column when the column is operated in co-current or at the bottom of the column when the column is operated in countercurrent.", "U.S. Pat. No. 4,412,866 describes a modification of a batch-fixed bed process and in particular relates to a simulated moving-bed in which separate zones are defined, each of which include one or more discrete vessels.", "The zones correspond to the functions of the process;", "typically sorption, displacement, desorption and rinsing.", "Booster pumps connected in series with the vessels maintain a desired pressure head for each zone.", "The functions of each zone are rotated in sequence, the sequence being timed in relation of the migration of the front between adjacent phases in the fluid loop circulating through the zones.", "Another type of absorption/desorption processes is a continuous process.", "Generally speaking an absorption/desorption process is classified as a continuous process when sorption, rinsing and desorption are conducted simultaneously and the product flow is uninterrupted.", "The use of a moving bed of resin allows one to obtain continuous operation and the main advantage is the high processing efficiency.", "As with batch processes, continuous processes can be operated as either co-current or countercurrent.", "Not all processes described as continuous are truly continuous processes.", "Truly continuous processes operate without interruption of either resin or liquid flows.", "Semicontinuous processes are often characterised by a short residence period in which ion-exchange absorption occurs (i.e. the service mode) followed by a period when the resin bed is moved (the moving mode).", "However, because the periods for both modes are very short, the processes virtually behave as a continuous one.", "More than a hundred semicontinuous processes are known, but only about six have any real industrial significance.", "To our understanding the widest known process of this type is the so-called Higgins Loop (and is described in the text by Higgins, I. R. and Roberts, I. T. “A countercurrent solid-liquid contactor for continuous ion-exchange.”", "Eng Prog.", "Symp.", "Ser.", ", 50, 87-94, 1950).", "The Higgins Loop is a continuous countercurrent ion-exchange process for liquid phase separations of ionic components using solid ion-exchange resin.", "The Higgins Loop comprises a vertical cylindrical vessel containing a packed-bed of ion-exchange resin that is separated into four operating zones by butterfly or loop valves.", "These operating zones—adsorption, desorption, backwashing and pulsing—function like four separate vessels.", "The Higgins Loop treats liquids in the sorption zone with resin while the ions are removed from loaded resin in the desorption zone simultaneously.", "Intermittently, a small portion of resin is removed from the respective zone and replaced with stripped or loaded resin at the opposite end of that zone.", "This is accomplished hydraulically by pulsation of the resin through the loop.", "The result is a continuous process that contacts liquid and resin in countercurrent flow.", "It is an object of the present invention to provide an alternative method and apparatus for desorbing materials sorbed on a resin that is capable of producing a concentrated eluate stream.", "SUMMARY OF THE INVENTION According to the present invention there is provided an apparatus for desorbing substances from an ion exchange resin having impurities and targeted materials sorbed thereon, the apparatus including: first and second chambers that are adapted so that when in use, resin is supplied to the first chamber and conveyed from the first chamber to the second chamber, and a desorption solution is supplied to the second chamber and conveyed from the second chamber to the first chamber such that, i) impurities having less affinity for the resin than the targeted material can be desorbed from the resin and targeted material can be sorbed onto the resin from the desorption solution, and thereby create conditions whereby an impurity stream having a high concentration of impurities and a relatively low concentration of targeted material can be discharged from the first chamber, and ii) targeted material can be desorbed from the resin in the second chamber and create conditions whereby a rich stream having a low concentration of impurities and a relatively high concentration of targeted material can be discharged from lower regions of the first and/or second chambers.", "In addition, when the apparatus is in use, it is preferred that the resin flows downwardly in the first chamber and upwardly in the second chamber, and that desorption solution flows in countercurrent to the direction of flow of resin in said chambers.", "It is even more preferred that the impurities stream be discharged from an upper region of the first chamber.", "It is preferred that the first and second chambers be connected in fluid communication such that the desorption solution can be conveyed from the second chamber to the first chamber.", "According to the present invention there is also provided an apparatus for desorbing material from a loaded ion exchange resin, the apparatus including: first and second chambers that are adapted so that in use, resin can move downwardly in the first chamber and upwardly in the second chamber and desorption solution can flow in counter current to the resin;", "first and second inlets for supplying loaded resin to the first chamber and desorption solution to the second chamber respectively, and first and second outlets for discharging a liquid from the apparatus and stripped resin from the second chamber respectively;", "means for facilitating the transferal of resin from the first chamber to the second chamber and conveying the resin upwardly in the second chamber;", "and in use, a first stream of desorption solution containing a relatively high concentration of impurities and a low concentration of targeted materials can be discharged from the first outlet, a second stream of desorption solution containing a relatively high concentration of targeted material and a low concentration of impurities can be discharged via the first outlet from lower regions of the first and/or second chambers and/or taken from desorption solution passing from the second chamber to the first chamber, and a stripped resin can be discharged from the second outlet of the second chamber.", "Advantages provided by the present invention include: ii) impurities having less affinity for the resin than the targeted material are desorbed from the resin before the targeted material and thus the first stream of desorption solution has a higher concentration of impurities can be discharged from the first chamber where the desorption solution first comes into contact with the resin;", "iii) upon desorption of the impurities from the resin, the capacity of the resin to absorb targeted materials increases which allows the first chamber to have a zone for re-adsorbing targeted materials onto the resin;", "and iv) targeted materials desorbed from the resin passes into the desorption solution and thereby increases the density of the solution so that it tends to settle under gravity in the chambers and thus facilitate the second stream of desorption solution containing a relatively high concentration of targeted substances and a low concentration of impurities to be discharged from the lower region of the apparatus.", "It is preferred that the desorption of impurities from the resin occurs in an upper zone of the first chamber and thereby allows further targeted material to be sorbed onto the resin in the upper zone.", "In other words, the upper zone forms re-adsorption zone.", "It is preferred that the first and second chambers be connected in fluid communication such that the liquid head in the second chamber causes the desorption solution to flow upwardly in the first chamber.", "It will be appreciated that as a result of the desorption solution being supplied into the second chamber, the predominant direction of flow of desorption solution is from the second chamber into the first chamber.", "It will also be appreciated that the net upwardly flow of desorption solution in the first chamber will be substantially equal to the rate at which the first stream of desorption solution is discharged from the first chamber.", "It is preferred that the first outlet for discharging the first stream of desorption solution be in an upper region of the first chamber.", "An advantage provided by this preferred feature is that the desorption solution first comes into contact with the resin in the upper region of the first chamber and impurities having less affinity for the resin than the targeted material can be withdrawn from the upper end of the first chamber.", "It is preferred that the second outlet for discharging stripped resin be located in the upper region of the second chamber.", "An advantage provided by this preferred aspect is that the resin is progressively exposed to a desorption solution having lower concentrations of targeted materials as the resin moves upwardly in the second chamber and thereby creates a larger potential for desorption of targeted materials from the resin in the second chamber before the resin is discharged from the apparatus.", "It is preferred that a passageway extend downwardly from the second outlet for conveying stripped resin to an intermediate chamber before being discharged from the apparatus.", "It is preferred that the first and second inlets for supplying resin and desorption solution into the first and second chambers respectively be located in the upper region of the chambers.", "It is preferred that the apparatus have control means for controlling the rate of removal of resin from the second chamber.", "In use, the control means measures the liquid level of the desorption solution in the first chamber to control the rate at which resin is removed form the second chamber.", "It is preferred that the second chamber have another inlet for supplying a concentrated solution of targeted materials into the second chamber.", "We have found that adding a concentrated solution into the second chamber further increases the concentration of the targeted materials in the second stream of desorption solution (ie an eluate stream) and decreases the concentration of impurities in the second stream.", "The preferred features of two embodiments of the present invention will now be described.", "It is preferred that the first and second chambers be interconnected by a passageway that extends from the first chamber to the second chamber, the passageway being adapted for conveying the resin and desorption between the chambers.", "According to one embodiment of the invention, it is also preferred that the first and second chambers be interconnected in U-shape having a base and two arms whereby the first and second chambers form the arms of the U-shape and the base provide the passageway.", "It is preferred that the second stream of desorption solution containing a high concentration of desorbed material be discharged from the passageway extending between the first and second chambers.", "In the instance when the first and second chambers are interconnected in a U-shape, the second stream of desorption solution having a high concentration of targeted material is discharged from the base of the U-shape.", "According to another embodiment of the invention, it is the preferred that the first and second chambers be arranged such that one of the chambers is located inside the other chamber.", "It is even more preferred that the second chamber be located concentrically within the first chamber.", "In the instance when the second chamber is located within the first chamber, it is preferred that the first chamber have an opening facing downwardly so that desorption solution from the second chamber can flow into the second chamber and that the resin from the second chamber enter the first chamber through the opening and be forced to move upwardly therein.", "It is preferred the second stream of desorption solution be discharged from the first chamber at a location below the opening of the second chamber.", "It is preferred that a bottom wall of the first chamber be declined toward an outlet for discharging the second stream of desorption solution having a high concentration of targeted substances.", "According to the present invention there is provided a method for desorbing substances from an ion exchange resin having impurities and targeted materials sorbed thereon, the method including treating an ion exchange resin in an apparatus having first and second chambers, wherein the method includes the steps: a) desorbing impurities from the resin in the first chamber using a desorption solution so that targeted materials having more affinity for the resin than the impurities can be sorbed onto the resin from the desorption solution and thereby creating conditions whereby a stream having a high concentration of impurities and a low concentration of targeted material can be discharged from the first chamber;", "and b) desorbing targeted materials from the resin treated according to step a) in the second chamber using the desorption solution and thereby create conditions whereby a stream having a high concentration of targeted materials and a low concentration of the impurities can be discharged from the apparatus.", "According to the present invention there is also provided a method for desorbing substances from a resin in an apparatus having first and second chambers connected in fluid communication, the method including the steps of: a) supplying a loaded resin having targeted materials and impurities sorbed thereon to the first chamber and the resin moving in a downward direction therein;", "b) conveying the resin from the first chamber to the second chamber and moving the resin in an upward direction therein;", "c) supplying a desorption solution to the second chamber such that the solution flows downwardly in the second chamber and upwardly in the first chamber in countercurrent flow to the resin;", "d) discharging stripped resin from the second chamber;", "e) discharging a first stream of desorption solution containing a high concentration of impurities and a low concentration of targeted substances from the first chamber;", "and a) discharging a second stream of desorption solution containing a relatively high concentration of targeted material and a relatively low concentration of impurities from a lower region of the first and/or second chambers and/or from the solution being conveyed between the chambers.", "It is preferred that any two or more of steps a) to f) be carried out simultaneously.", "It is preferred that the impurities on the resin have less affinity for the resin than the targeted materials so that when the resin is contacted by the desorption solution in the first chamber, the impurities tend to be desorbed from the resin before desorption of the targeted materials.", "It is preferred that the desorption of impurities from the resin occurs in an upper zone of the first chamber and thereby allows further targeted material to be sorbed into the resin in the upper zone.", "It is therefore preferred that the first stream discharged in step e) be discharging the upper region of the first chamber.", "It is preferred that targeted materials desorbed from the resin and dissolved into solution increase the density of the solution thus causing fractions of the solution having high concentrations of targeted solutions to settle under gravity toward the lower regions of the first and second chambers.", "It is therefore preferred that the second stream discharged in step f) be discharged from the solution being conveyed between the chambers or from the lower regions of the first and/or second chambers.", "It is preferred that the rate, at which resin is discharged in step d), be controlled by the liquid level in the first chamber.", "It is preferred that the resin discharged in step d) be discharged from upper regions of the second chamber.", "It is preferred that the method also include supplying a concentrated solution of targeted substances into the second chamber.", "We have found that adding a solution of concentrated solution into the second chamber further increases the concentration of the targeted substances in the second stream of desorption solution (ie an eluate stream) and decreases the concentration of impurities in the second stream.", "It is preferred the temperature of the concentrated solution range from approximately 60 to 100° C. It is preferred that the additional solution be supplied into the second chamber at a location between the upper and lower regions of the second chamber.", "The method of the present invention may also include any one of the features of the apparatus described above.", "BRIEF DESCRIPTION OF THE DRAWINGS Two preferred embodiments of the present invention will now be described with reference to the accompanying drawings, of which: FIG. 1 illustrates an apparatus for desorbing material from a resin according to one embodiment of the invention, wherein the apparatus includes two chambers one chamber is located inside the other;", "FIGS. 2 and 3 illustrate the embodiment shown in FIG. 1 with additional features;", "FIG. 4 illustrates an apparatus for desorbing material according to an alternative embodiment, wherein the apparatus includes two chambers interconnected in a U-shape;", "and FIGS. 5 and 6 illustrate the embodiment shown in FIG. 4 with additional features.", "DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The two preferred embodiments have a number of features in common and the same reference numerals have been used to identify the same or alike features on both embodiments where possible.", "The preferred embodiment illustrated in the FIG. 1 comprises an apparatus having two chambers in which an inner chamber 1 is located concentrically within the outer chamber 2 .", "The inner chamber 1 has an inlet valve 14 for supplying desorption solution to the inner chamber and an outlet for stripped resin.", "Extending from the outlet is a conduit that feeds stripped resin into an intermediate tank 7 .", "The lower end of the inner chamber 1 has an opening facing downwardly so that desorption solution flows downwardly in the inner 1 chamber and upwardly in the outer chamber 2 in the direction of the dashed arrows.", "The liquid head of desorption solution in the inner chamber 1 causes the desorption solution to flow upwardly in the outer chamber 2 .", "The outer chamber 2 has a resin inlet or spigot 5 for supplying saturated resin into the outer chamber 2 .", "Resin in the outer chamber 2 moves downwardly in the direction of the arrows shown in solid lines in countercurrent to the desorption solution.", "The resin is also forced through the opening in the inner chamber 1 and upwardly in the inner chamber 1 in the direction of the arrows shown in solid lines in countercurrent flow to the desorption solution.", "In use, loaded resin enters through the spigot 5 and contacts the loaded resin in the top of the outer chamber 2 .", "At first instance, impurities having less affinity for the resin than the targeted material are desorbed from the resin.", "As a result, a stream of desorption solution having a high concentration of impurities is discharged via outlet drain 3 .", "Upon desorption of the impurities form the resin, the capacity of the resin for sorbing targeted material may increase such that an upper region of the outer chamber 1 in which the impurities are desorbed may also form a re-adsorption zone for re-adsorbing the targeted material onto the resin.", "Normally, the re-adsorbing zone formed in the upper region of the first chamber 1 keeps the concentration of the targeted materials low in the stream of desorption solution discharged via the outlet drain 3 .", "The loaded resin migrates down past the re-adsorption zone and into the inner chamber 1 where targeted material is desorbed in a desorption zone of the apparatus.", "Resin moves along the inner and outer chambers 1 and 2 using any suitable means such as resin pulsation.", "In the case of the embodiment shown in FIGS. 1 to 3 , resin pulsation is carried out by opening valve 13 for discharging resin from apparatus, closing valve 14 so as interrupted the supply of desorption solution and pumping air into the column via the spigot 6 located on the top of the re-adsorption zone.", "Electrodes 9 and 10 , which measure the level of desorption solution in the outer chamber 2 of the apparatus control the rate at which resin is removed from the apparatus.", "Resin movement within the chambers 1 and 2 may take place periodically once every 0.5-3.0 hours and continue for about 0.5-2.0 minutes depending on the properties of the resin, the targeted material and the conditions of the desorption process.", "Desorption solution is pumped into the inner chamber 1 via the spigot 4 and the valve 14 .", "Desorption solution strips the target material from the oversaturated resin during its movement past desorption zone 1 downwardly to the bottom of the apparatus.", "A stream of desorption solution containing a high concentration of targeted material and a low concentration of the impurities is discharged from the bottom of the apparatus via the pipe 8 .", "The flow of solution from the bottom of the apparatus is regulated using valve 15 .", "A screen 11 at the bottom of the apparatus retains the resin in the outer chamber 2 as solution is discharged.", "FIGS. 2 and 3 illustrate the apparatus shown in FIG. 1 having an inlet 12 for supplying a concentrated solution of targeted materials into the middle of the inner chamber 1 .", "We have found that the addition of a concentrated solution to the inner chamber 1 reduces the concentration of impurities and increases the concentration of targeted material discharged from the apparatus through valve 15 .", "FIG. 3 illustrates the apparatus fitted with a heat exchange means for preheating the desorption solution supplied into the inner chamber 1 via inlet 12 and valve 14 for aiding the desorption of material from resin to the desorption solution.", "The desorption solution is preferably heated to a temperature ranging from 60° C. to 100° C. The apparatus is also includes external insulation for maintaining the temperature of the desorption solution in the chambers 1 and 2 .", "FIG. 4 illustrates an alternative embodiment in which the chambers 1 and 2 are interconnected in a U-shape.", "Specifically, chambers extend upwardly from opposite ends of a horizontal passageway that interconnects the chambers.", "The diameter of the passageway is substantially the same as the diameter of the chambers 1 and 2 such that the resin can be conveyed from chamber 2 to chamber 1 using the pulsation techniques described above.", "The passageway also provides fluid communication between the chambers 1 and 2 such that liquid head of desorption solution in chamber 1 causes desorption solution to flow upwardly in the outer chamber 2 .", "Moreover, the embodiment shown in FIGS. 4 to 6 includes the same features as the embodiment shown in FIGS. 1 to 3 and can be operated in the same manner.", "The same reference numerals have been used on both embodiments to show the same features.", "It is envisaged that the embodiments of the present invention can be operated so that the resin and desorption solution flow continuously and in countercurrent.", "However, it will appreciated by those skilled in the art that the flow of desorption solution and the movement of resin may be intermittent and in general terms, a continuous desorption process is one in which resin moves intermittently through a desorption apparatus.", "In particular, the movement of resin in a desorption apparatus normally involves an the resin being moved along the bed in intermitted increments whereby a slug of resin is discharged from an end of the bed and the rest of the resin moves in a direction along the bed.", "The present invention will now be described with reference to the following non-limiting examples.", "EXAMPLE 1 This example illustrates the desorption of copper from the resin that was saturated during the treatment of a waste-water steam of a copper electroplating plant.", "The example was carried out using the apparatus design as shown on FIG. 4 .", "The copper concentration in the rinse water was about 50-80 ppm and the resin loading capacity reached 28-32 g/l.", "The desorption trial was performed in a 150 L-plastic U-shape column in accordance with the embodiment shown in FIG. 4 .", "The loaded resin entered the column via the spigot 5 located on the lid of the column.", "After desorption the fully stripped resin was removed on an hourly basis from the column through the transfer pipe and the intermediate tank 7 .", "The resin passed through the column at a rate of 20 L/hr.", "A 7% solution of sulphuric acid was used as the desorption solution.", "A desorption stream was pumped at a rate of about 22 L/hr into the top of the desorption zone of the column via the spigot 4 with valve 14 in the open position.", "A waste stream was removed via the drainage 3 at the rate of 11.51/hr-12.51/hr.", "The copper concentration in the waste stream was less than 200 ppm and was returned together with the rinse water to the sorption stage.", "An eluate stream was collected from the bottom of the column through screen 11 and pipe 8 .", "The eluate solution was discharged at a rate of 9.5-10.51/hr using valve 15 .", "The copper concentration reached 60 g/l in the eluate stream, very near to the maximum of the solubility of the copper sulphate (CuSO 4 [.", "].5H 2 O) (bluestone).", "The eluate stream is analytically and economically suitable for the direct copper recovery using the well-known methods such as copper electrowinning or cupric sulphate precipitation.", "It is envisaged that an eluate stream formed by the above example can be used directly in a copper-electroplating bath and the waste rinse water containing copper can be returned to the production circuit a copper electroplating plant.", "It is also envisaged that the treated water may be returned to a water system of the copper electroplating plant.", "EXAMPLE 2 This example illustrates desorption of nickel from the resin, which was loaded during the sorption recovery of nickel from high-pressure laterite leach slurry.", "The example was carried out using the apparatus shown in FIG. 4 .", "Elemental analysis for the loaded resin is shown in Table 2.1.", "The desorption equipment consisted of a U-shape plastic laboratory column with volume 750 ml.", "The resin flowed through the column at a rate of 100 ml/hr.", "A 10% solution of hydrochloric acid was used as a desorption liquor.", "The solution was pumped into the column via the spigot 4 and the valve 14 and flowed through the desorption and re-absorption zones at rate about 160 ml/hr.", "The flow of the desorption solution was divided to two unequal parts: i) The waste solution stream, which was collected after desorption from the drainage 3 at volume about 100 ml/hr and input to the sorption stage together with the pregnant leach slurry.", "ii) The resulting eluate stream, which was collected from the bottom of the column via the pipe 15 and the opened partly valve 8 at volume 60 ml/hr.", "Elemental analysis for the eluate and waste streams are set out below in Table 2.1.", "TABLE 2.1 Results of the elemental analysis of the starting and resulting products.", "Loaded resin, Eluate stream Waste stream, Elements g/l ppm ppm Ni 36.81 59 510 382 Co 1.65 1 460 493 Mn 2.16 701 2 750 Mg 3.40 72 2 560 Fe 0.18 127 <0.001 Cu 0.27 69 0.08 Zn 0.22 141 86 Ca 0.35 103 396 Si 0.02 30 0.24 Cr 0.01 1.34 0.65 Al 0.24 123 6.05 These results of the example show that the concentration of nickel in the eluate was about 60 g/l, which we estimate to be approximately 60% greater than the loading capacity of the pregnant resin.", "It is also noted that the majority of impurities, for example magnesium and manganese were discharged in the waste solution discharged via outlet 3 and as a result, the high concentrated eluate is suitable for nickel electrowinning recovery.", "EXAMPLE 3 This example illustrates desorption of copper from a saturated resin, which was previously loaded during the sorption copper recovery from the heap leaching liquor.", "The copper concentration was between 2 g/l to 6 g/l.", "The loading capacity of the resin, involved in this copper trial, was 55-64 g/l.", "During this test the resin flowed through the desorption column at a rate of approximately 100 ml/hr.", "The desorption trial was performed in a 750 ml borosilicate glass column in accordance with the apparatus shown in FIG. 6 .", "The U-shape column was fully insulated to keep the temperature within the column between 60-70° C. A 10% solution of sulphuric acid was used as a desorbent, which was preheated up to 60-70° C. using an electric heater, on the inlet 4 of the desorption solution.", "The flow of the desorbent was maintained at rate of about 75 ml/hr In addition, a preheated mother liquor, after the precipitation of the copper sulphate, was pumped into the middle of chamber 1 through the inlet tube 12 with a throughput of about 85 ml/hr.", "In this mother liquor, the copper concentration was about 45 g/l.", "A waste stream was removed from chamber 2 through the drainage 3 at rate of ˜60 ml/hr and the copper concentration was less than 100 ppm.", "This waste solution may be reused in the copper heap leaching process.", "A saturated eluate stream was collected from the bottom of the apparatus via the pipe 8 and the adjusting valve 15 at a rate of 100 ml/hr, with a copper concentration of about 100 g/l and temperature ˜65° C. The eluate stream was cooled to 20° C. with continuous mixing and approximately 234 g of the copper sulphate crystals were precipitated from every liter of the eluate stream.", "After filtration of the copper sulphate crystals, the mother liquor with the copper concentration about 45 g/l was heated to ˜70° C. and reused to supply inlet tube 12 .", "EXAMPLE 4 This example illustrates the desorption of molybdenum from a loaded resin that was saturated during adsorption from molybdenum-containing solutions.", "The molybdenum concentration of these solutions was ˜1 g/l, so the equilibrium loading capacity of the resin was about 100 g/l.", "A desorption trail was performed in a 30 L column in accordance with the apparatus shown in FIG. 1 .", "The loaded resin was placed into the outer chamber 2 of the column via the spigot 5 .", "During this trail the resin flow was maintained at rate of ˜3 l/hr.", "A 10% ammoniac solution was used as a desorbent.", "This solution was pumped into the inner chamber 1 of the column via the spigot 4 with valve 14 in the open position.", "The throughout was kept 4 l/hr.", "A waste solution stream with a molybdenum concentration of less than 200 ppm was collected from drainage 3 at rate of about 2 l/hr and returned with the pregnant solution on the sorption stage.", "A saturated eluate stream was collected from the bottom of the column through the screen 11 and the pipe 8 .", "The volume of the removed eluate was regulated using the valve 15 .", "The molybdenum concentration of the eluate stream was ˜150 g/l and the main impurities concentrations were negligible.", "The solution is suitable for the economical recovery of the chemical grade ammonium paramolibdate.", "EXAMPLE 5 This example illustrates a method of nickel desorption from a saturated resin with the nickel loading capacity of about 42 g/l.", "The resin was loaded during the sorption nickel recovery from the atmospheric leach laterite slurry.", "A desorption equipment consisted of a 750 ml column in accordance with the embodiment shown in FIG. 3 .", "The loaded resin was placed into the column through the spigot 5 .", "The resin flow during this test was kept at rate of ˜100 ml/hr.", "A 10% solution of sulphuric acid was used as the desorption solution.", "The throughout of the desorbent was regulated by the peristaltic pump and maintained at rate of ˜75 ml/hr.", "The desorbent was pumped into the top of the desorption zone of the column via the spigot 4 and the valve 14 .", "The solution after the nickel electrowinning process contained 43 g/l and was pumped into the middle of the desorption zone of the column at rate of ˜85 ml/hr through the drainage 12 .", "A waste solution stream (about 60 ml/hr) was removed from the column via the drainage 3 .", "This solution contains about 200 ppm of nickel may be reused in the leaching process.", "An eluate stream was collected from the bottom of the column through the valve 15 and the pipe 8 at rate of about 100 ml/hr and contained about 85 g/l of nickel.", "This solution may be used for the nickel electrowinning." ]
TECHNICAL FIELD [0001] This disclosure relates to fuel cell systems and specifically to sensing a concentration of fuel within a fuel cell system. BACKGROUND [0002] A fuel cell is an energy conversion device that generates electrical energy and thermal energy by electrochemically combining a gaseous fuel and an oxidant gas across an ion conducting electrolyte. Several types of fuel cells currently exist. A characteristic difference between distinct types of fuel cell is the type of material used for the electrolyte. The difference in the materials of the electrolyte employed distinguishes the fuel cells due to the operating temperature ranges of the materials. In one type of fuel cell, the Solid Oxide Fuel Cell (SOFC), the fuel cell is constructed from solid-state materials utilizing an ion-conducting oxide ceramic as the electrolyte. To generate a useful quantity of power, a fuel cell is made up of multiple fuel cell units in a series array, typically stacked together. A single SOFC unit consists of two electrodes, one is an anode and one is a cathode. The anode and the cathode are separated by the solid electrolyte just identified. Fuel for the SOFC is typically gaseous hydrogen and carbon monoxide supplied in from reformate, and the oxidant is commonly an air supply. The fuel cell operates when the oxidant contacts the cathode and the fuel contacts the anode. The electrolyte conducts the oxygen ions between the cathode and the anode maintaining an overall electrical charge balance in the system. Electrons are released from the fuel cell to an external circuit forming a flow of electrons. The flow of electrons released from the fuel cell to the external circuit provides useful electrical power. [0003] The production of useful electrical power is the primary function of the SOFC. Optimizing the conversion of fuel in the fuel cell is an endeavor that commands a significant amount of time and effort. As in many other energy conversion devices, the function of converting the fuel into useful energy, (electrical energy, thermal energy), is closely monitored by system operators. Quantifying the concentration of fuel flowing in the fuel cell provides a benefit during the operation of the fuel cell. The performance of the fuel cell is related to, and optimized by knowing the concentration of fuel being supplied to the fuel cell. Understanding the fuel concentration allows operators to understand what quantity of fuel to supply, and what electrical load to apply. Unfortunately, directly measuring the concentration of fuel such as hydrogen in the fuel cell creates many engineering challenges due to the limitations of hydrogen concentration sensors. The limitations of directly measuring hydrogen concentrations with sensors are amplified when applied to the SOFC, because the SOFC operates at high temperatures and uses high concentrations of hydrogen. The limitations are greatest with respect to sensing the concentration of hydrogen and the material compatibility of the sensor. [0004] Direct measurement hydrogen concentration sensors are designed for concentrations that are very small compared to the relatively high SOFC hydrogen concentrations that exist during fuel cell operation. As a result, the direct measurement hydrogen concentration sensors are inadequate for use with solid oxide fuel cells. [0005] In addition to the forgoing, existing hydrogen concentration sensors that measure hydrogen concentrations directly are not compatible with SOFC operating environments. Typically SOFC's exhibit high operating temperatures and a harsh environment both of which are detrimental to direct measurement hydrogen concentration sensors. Thus, there is a need in the art for a sensor that is compatible with both the operating environment and the relatively high levels of hydrogen concentration of the SOFC. SUMMARY [0006] Fuel concentrations are determinable in a solid oxide fuel cell through voltage measurement of one or more fuel cell units, which voltage is a function of hydrogen gas present in the fuel feed stream to the one or more fuel cell units. The voltage in the one or more fuel cell units is proportionally related to the fuel concentration in the fuel feed stream to the entire fuel cell. A sensor determines concentrations of the fuel flowing in the fuel cell. The sensor comprises a fuel cell unit, and an indicator electrically coupled to the fuel cell unit, the indicator being capable of displaying a voltage or being adapted to convert a voltage to a fuel concentration display. The voltage measured is correlated to the fuel concentration flowing in the fuel cell. The above described and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS [0007] The sensor will now be described, by way of an example, with references to the accompanying drawings, wherein like elements are numbered alike in the several figures: [0008] [0008]FIG. 1 is a schematic plan view of a fuel cell making up all or a part of a fuel cell; [0009] [0009]FIG. 2 is a schematic plan view of an exemplary embodiment of a fuel cell unit based sensor. DESCRIPTION OF THE PREFERRED EMBODIMENT [0010] Referring to FIG. 1, an exemplary embodiment of a fuel cell unit 10 is shown. In one embodiment, the fuel cell unit 10 is an assembly of an electrolyte 12 , an anode 14 and a cathode 16 , with the electrolyte 12 positioned between the anode 14 and the cathode 16 as illustrated. In a working fuel cell, one or more fuel cell units are employable. Typically more than one unit is employed to increase the total electrical energy output. In such multiple unit fuel cells, fuel cell unit 10 is repeated over and over to provide a serial assay of fuel cell units 10 to produce a desired quantity of electrical energy and thermal energy. [0011] An understanding of the components of a solid oxide fuel cell and its operation will be helpful to understand this disclosure. The ceramic electrolyte 12 , in one embodiment, is an yttria-stabilized-zirconia (YSZ). This ceramic electrolyte 12 exhibits good oxygen ionic conductivity and little electrical conductivity at high temperatures (700-1000 degrees centigrade). The electrodes, in one embodiment, are porous, gas-diffusion electrodes. The anode 14 is about 20-40 percent porous and is formed from a metallic nickel and an YSZ skeleton for thermal compatibility with the other components. The cathode 16 is made from strontium-doped lanthanum manganite with about the same porosity as the above embodiment of the anode 14 . In other embodiments the materials may vary. Because the fuel cell is solid state, the thermal expansion coefficients of as many as four different ceramic layers must be well matched in the fuel cell unit 10 . A high operating cell temperature in the SOFC is required to maximize the ionic conductivity of the electrolyte and ensure good electrical conductivity of the electrodes and interconnections. As a result, the critical cell components are made from various ceramics, metal-ceramic composites, and high temperature alloys that are compatible with the operating environment of the SOFC. [0012] The fuel cell unit 10 may be configured in a variety of geometries including tubular planar stack and radial planar geometries. The fundamental electrochemical processes of the fuel cell unit 10 remain the same for various cell geometries. In the embodiment shown in FIG. 1, during operation, fuel 18 , (typically reformate containing hydrogen reformed from diesel fuel, gasoline, natural gas, propane, or methanol), flows through channel 22 and oxidant 20 , typically air, flows through channel 24 , respectively. Each electrode, (cathode 16 , anode 14 ), is exposed to the reactant gases 20 , 18 . The anode 14 is exposed to or contacted with the fuel 18 and the cathode 16 is exposed to or contacted with the oxidant 20 . More specifically, the fuel cell unit 10 operates when the oxidant 20 having oxygen ions 26 , contacts the cathode 16 , where the oxygen ions 26 are adsorbed by the cathode 16 . The oxygen ions 26 diffuse to the cathode-electrolyte interface and are reduced, (gains electrons). The mobile ionic species are negatively charged oxygen ions. Continuing with the fuel cell operation, negative ions (anions) 28 migrate across the electrolyte 12 . The migrating anions 28 carry the negative charge to the electrolyte-anode interface. At the anode 14 , hydrogen 19 is oxidized. Because of hydrogen's affinity for oxygen, the hydrogen 19 flowing past the anode 14 is adsorbed by the anode 14 , where the hydrogen diffuses through the porous anode 14 to the anode-electrolyte interface, where as mentioned above, the hydrogen 19 is oxidized (loses electrons). The fuel cell unit 10 creates a flow of electrons 30 (electron flow). The flow of electrons 30 is conducted to an electrical load 32 via an electrical circuit (not shown). The electrical circuit maintains the flow of electrons 30 from the anode 14 to the electrical load 32 and continues to the cathode 16 . The electron flow 30 flows from the negative charge at the anode 14 to the positive charge at the cathode 16 . The electrical current (not shown), flows opposite the electron flow 30 from a high electrical potential at the cathode 16 to a low electrical potential at the anode 14 . In addition to electron flow 30 , the fuel cell produces reaction products from both electrodes while in operation. The anode reaction products 34 (product gases and depleted fuel, or combustion products) of the fuel cell unit 10 are typically water, carbon dioxide, hydrogen, carbon monoxide and other products, depending on the fuel 18 . Thermal energy is also a discharged product 34 . Cathode reaction products 36 (excess or depleted oxidant and product gases), typically air and water are also discharged. As stated previously, the fuel cell unit 10 , including the electrolyte 12 disposed between the anode 14 and the cathode 16 produces a limited quantity of electrical energy and thermal energy. Combining an individual fuel cell unit 10 with multiple fuel cell units 10 otherwise known as stacking, increases generating capacity amounting to a quantity of useful electrical and thermal energy. The serial array of individual fuel cell units 10 , creates a complete fuel cell 100 , (sometimes known as a fuel cell stack 102 ) (not shown). [0013] The electrochemical processes that occur in the fuel cell unit 10 can be related to the electrochemical processes that occur in the entire fuel cell 100 . The flow of electrons 30 from the fuel cell unit 10 is related to the sum of all electrons flowing 30 through the entire fuel cell 100 . The electrons flowing 30 through the fuel cell 100 are related to an electrical potential of fuel cell 100 . Electrical potential is measured as voltage. The voltage of the fuel cell 100 is a strong function of the concentration of the hydrogen 19 (fuel 18 ) in the feed stream of fuel of fuel cell 100 . Likewise, the voltage of the fuel cell unit 10 is a strong function of the concentration of the hydrogen 19 (fuel 18 ) in the feed stream of fuel to the fuel cell unit 10 . Stated another way, the concentration of the hydrogen in the fuel cell 100 is related to the flow of electrons 30 and to the electrical load 32 . The operability of the fuel cell 100 is related to the concentration of fuel 18 in the fuel cell 100 . Throughout the operation of the fuel cell 100 , the concentration of fuel 18 , is a parameter that indicates SOFC system performance. In a preferred embodiment, the concentration of hydrogen is a parameter that is used to optimize the performance of the fuel cell 100 . More specifically, the knowledge of the concentration of the hydrogen in the fuel stream being presented to the stack of fuel cell units 10 is a parameter that can be used to optimize the performance of the system. It has been determined by the inventors herein that measured voltage of one or more fuel cell units can be repeatably and reliably correlated to a a concentration of reformate flowing in the fuel stream to the fuel cell. The relationship of the flow of electrons 30 to the concentration of hydrogen 19 allows for measurement of the concentration of hydrogen 19 indirectly by measuring the voltage of one or more fuel cell unit(s) 10 . The voltage measurement of even a single fuel cell is correlatable to the reformate concentration in the entire fuel cell 100 . [0014] Turning now to FIG. 2, an exemplary embodiment of a fuel cell based fuel concentration sensor 40 , hereinafter, sensor 40 , is shown. The fundamental electrochemical processes of the sensor 40 remains the same as the electrochemical processes of the fuel cell unit 10 regardless of the various cell geometries. FIG. 2, illustrates an arrangement of a preferred embodiment of a sensor 40 that directly measures the voltage of the fuel cell unit 10 and indirectly allows determination of the concentration of hydrogen in the fuel cell 100 . The sensor 40 has the same basic components and materials as the fuel cell unit 10 shown in FIG. 1, with the substitution of the electrical load 32 for an indicator 42 . The indicator 42 measures and indicates the voltage of the sensor 40 . The components of an individual fuel cell unit 10 or, in one embodiment, a portion of the fuel cell unit 10 is utilized as the sensor 40 . The sensor 40 is nestable with the fuel cell 100 . In an embodiment, multiple sensors 40 are disposed or nested within the fuel cell 100 . Sensors 40 can be intermittently disposed throughout the fuel cell 100 stack to provide an array of indications within the cell geometry. In certain fuel cell 100 geometries, the fuel cell units 10 may experience different operating conditions at different locations within the fuel cell 100 , so placement of individual sensors 40 in different locations within the stack is also contemplated. In the preferred embodiment, the sensor 40 is not electrically connected to other fuel cell units 10 in the stack of the fuel cell 100 . The sensor 40 is isolatable from the fuel cell 100 stack. The sensor 40 is not connected to the electrical load 32 . [0015] The sensor 40 has the material properties to function in the environment of the fuel cell unit 10 . A hydrogen concentration sensor made from the same materials as the fuel cell components can withstand the SOFC operating environment. In a preferred embodiment, the sensor 40 has the same electrolyte 12 materials, the same anode 14 materials and the same cathode 16 materials as an individual fuel cell unit 10 . The sensor 40 is capable of determining the high concentrations of fuel that are encountered in the fuel cell unit 10 . The capability to determine the relatively high concentrations is due to the proportional relationship of the voltage and the fuel concentration in the fuel cell unit 10 . In a preferred embodiment, the sensor 40 is compatible with the SOFC using hydrogen as a fuel, where the hydrogen has a wide range of concentrations. A hydrogen concentration sensor that is not limited to relatively small hydrogen concentrations can measure hydrogen concentrations within the SOFC. [0016] Measuring the voltage with the sensor 40 provides data which is correlatable to the hydrogen concentration in the fuel cell 100 because the voltage of the sensor is proportional to the concentration of hydrogen being presented to the fuel cell 100 . The indicator 42 , in one embodiment, can be used simply to provide the data taken from measuring the voltage. The data can then be used to correlate the voltage to the hydrogen concentration. In another embodiment, the indicator 42 can measure the voltage and correlate the data taken from the measurement into a hydrogen concentration in a display. Measuring the voltage of the sensor 40 enables monitoring hydrogen 19 concentrations or other fuel 18 concentrations in other embodiments. [0017] A comparison of the voltage measured in the electrically isolated sensor 40 to the total voltage of the electrically loaded fuel cell units 10 stacked in the fuel cell 100 is also considered in an alternate embodiment. A variety of fuel cell 100 performance characteristics can be assessed, such as contamination within the fuel cell unit 10 , aging, and fuel cell efficiency, by knowing the concentration of hydrogen in the fuel cell 100 . The fuel cell unit 10 fuel flow rates as well as electrical load 32 can be controlled more efficiently as a result of having the capability to detect the voltage of the sensor 40 and correlate a fuel concentration in the fuel cell 100 . It is contemplated that applying varying electrical loads 32 to the sensor 40 and measuring the output impedance of the sensor 40 thus determining a relationship of the concentration of reformate (fuel 18 ) with the output impedance of the sensor 40 . [0018] While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims.
Fuel concentrations are determinable in a solid oxide fuel cell through voltage measurement of one or more fuel cell units, which voltage is a function of hydrogen gas present in the fuel feed stream to the one or more fuel cell units. The voltage in the one or more fuel cell units is proportionally related to the fuel concentration in the fuel feed stream to the entire fuel cell. A sensor determines concentrations of the fuel flowing in the fuel cell. The sensor comprises a fuel cell unit, and an indicator electrically coupled to the fuel cell unit, the indicator being capable of displaying a voltage or being adapted to convert a voltage to a fuel concentration display. The voltage measured is correlated to the fuel concentration flowing in the fuel cell.
Provide a concise summary of the essential information conveyed in the context.
[ "TECHNICAL FIELD [0001] This disclosure relates to fuel cell systems and specifically to sensing a concentration of fuel within a fuel cell system.", "BACKGROUND [0002] A fuel cell is an energy conversion device that generates electrical energy and thermal energy by electrochemically combining a gaseous fuel and an oxidant gas across an ion conducting electrolyte.", "Several types of fuel cells currently exist.", "A characteristic difference between distinct types of fuel cell is the type of material used for the electrolyte.", "The difference in the materials of the electrolyte employed distinguishes the fuel cells due to the operating temperature ranges of the materials.", "In one type of fuel cell, the Solid Oxide Fuel Cell (SOFC), the fuel cell is constructed from solid-state materials utilizing an ion-conducting oxide ceramic as the electrolyte.", "To generate a useful quantity of power, a fuel cell is made up of multiple fuel cell units in a series array, typically stacked together.", "A single SOFC unit consists of two electrodes, one is an anode and one is a cathode.", "The anode and the cathode are separated by the solid electrolyte just identified.", "Fuel for the SOFC is typically gaseous hydrogen and carbon monoxide supplied in from reformate, and the oxidant is commonly an air supply.", "The fuel cell operates when the oxidant contacts the cathode and the fuel contacts the anode.", "The electrolyte conducts the oxygen ions between the cathode and the anode maintaining an overall electrical charge balance in the system.", "Electrons are released from the fuel cell to an external circuit forming a flow of electrons.", "The flow of electrons released from the fuel cell to the external circuit provides useful electrical power.", "[0003] The production of useful electrical power is the primary function of the SOFC.", "Optimizing the conversion of fuel in the fuel cell is an endeavor that commands a significant amount of time and effort.", "As in many other energy conversion devices, the function of converting the fuel into useful energy, (electrical energy, thermal energy), is closely monitored by system operators.", "Quantifying the concentration of fuel flowing in the fuel cell provides a benefit during the operation of the fuel cell.", "The performance of the fuel cell is related to, and optimized by knowing the concentration of fuel being supplied to the fuel cell.", "Understanding the fuel concentration allows operators to understand what quantity of fuel to supply, and what electrical load to apply.", "Unfortunately, directly measuring the concentration of fuel such as hydrogen in the fuel cell creates many engineering challenges due to the limitations of hydrogen concentration sensors.", "The limitations of directly measuring hydrogen concentrations with sensors are amplified when applied to the SOFC, because the SOFC operates at high temperatures and uses high concentrations of hydrogen.", "The limitations are greatest with respect to sensing the concentration of hydrogen and the material compatibility of the sensor.", "[0004] Direct measurement hydrogen concentration sensors are designed for concentrations that are very small compared to the relatively high SOFC hydrogen concentrations that exist during fuel cell operation.", "As a result, the direct measurement hydrogen concentration sensors are inadequate for use with solid oxide fuel cells.", "[0005] In addition to the forgoing, existing hydrogen concentration sensors that measure hydrogen concentrations directly are not compatible with SOFC operating environments.", "Typically SOFC's exhibit high operating temperatures and a harsh environment both of which are detrimental to direct measurement hydrogen concentration sensors.", "Thus, there is a need in the art for a sensor that is compatible with both the operating environment and the relatively high levels of hydrogen concentration of the SOFC.", "SUMMARY [0006] Fuel concentrations are determinable in a solid oxide fuel cell through voltage measurement of one or more fuel cell units, which voltage is a function of hydrogen gas present in the fuel feed stream to the one or more fuel cell units.", "The voltage in the one or more fuel cell units is proportionally related to the fuel concentration in the fuel feed stream to the entire fuel cell.", "A sensor determines concentrations of the fuel flowing in the fuel cell.", "The sensor comprises a fuel cell unit, and an indicator electrically coupled to the fuel cell unit, the indicator being capable of displaying a voltage or being adapted to convert a voltage to a fuel concentration display.", "The voltage measured is correlated to the fuel concentration flowing in the fuel cell.", "The above described and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description, drawings, and claims.", "BRIEF DESCRIPTION OF THE DRAWINGS [0007] The sensor will now be described, by way of an example, with references to the accompanying drawings, wherein like elements are numbered alike in the several figures: [0008] [0008 ]FIG. 1 is a schematic plan view of a fuel cell making up all or a part of a fuel cell;", "[0009] [0009 ]FIG. 2 is a schematic plan view of an exemplary embodiment of a fuel cell unit based sensor.", "DESCRIPTION OF THE PREFERRED EMBODIMENT [0010] Referring to FIG. 1, an exemplary embodiment of a fuel cell unit 10 is shown.", "In one embodiment, the fuel cell unit 10 is an assembly of an electrolyte 12 , an anode 14 and a cathode 16 , with the electrolyte 12 positioned between the anode 14 and the cathode 16 as illustrated.", "In a working fuel cell, one or more fuel cell units are employable.", "Typically more than one unit is employed to increase the total electrical energy output.", "In such multiple unit fuel cells, fuel cell unit 10 is repeated over and over to provide a serial assay of fuel cell units 10 to produce a desired quantity of electrical energy and thermal energy.", "[0011] An understanding of the components of a solid oxide fuel cell and its operation will be helpful to understand this disclosure.", "The ceramic electrolyte 12 , in one embodiment, is an yttria-stabilized-zirconia (YSZ).", "This ceramic electrolyte 12 exhibits good oxygen ionic conductivity and little electrical conductivity at high temperatures (700-1000 degrees centigrade).", "The electrodes, in one embodiment, are porous, gas-diffusion electrodes.", "The anode 14 is about 20-40 percent porous and is formed from a metallic nickel and an YSZ skeleton for thermal compatibility with the other components.", "The cathode 16 is made from strontium-doped lanthanum manganite with about the same porosity as the above embodiment of the anode 14 .", "In other embodiments the materials may vary.", "Because the fuel cell is solid state, the thermal expansion coefficients of as many as four different ceramic layers must be well matched in the fuel cell unit 10 .", "A high operating cell temperature in the SOFC is required to maximize the ionic conductivity of the electrolyte and ensure good electrical conductivity of the electrodes and interconnections.", "As a result, the critical cell components are made from various ceramics, metal-ceramic composites, and high temperature alloys that are compatible with the operating environment of the SOFC.", "[0012] The fuel cell unit 10 may be configured in a variety of geometries including tubular planar stack and radial planar geometries.", "The fundamental electrochemical processes of the fuel cell unit 10 remain the same for various cell geometries.", "In the embodiment shown in FIG. 1, during operation, fuel 18 , (typically reformate containing hydrogen reformed from diesel fuel, gasoline, natural gas, propane, or methanol), flows through channel 22 and oxidant 20 , typically air, flows through channel 24 , respectively.", "Each electrode, (cathode 16 , anode 14 ), is exposed to the reactant gases 20 , 18 .", "The anode 14 is exposed to or contacted with the fuel 18 and the cathode 16 is exposed to or contacted with the oxidant 20 .", "More specifically, the fuel cell unit 10 operates when the oxidant 20 having oxygen ions 26 , contacts the cathode 16 , where the oxygen ions 26 are adsorbed by the cathode 16 .", "The oxygen ions 26 diffuse to the cathode-electrolyte interface and are reduced, (gains electrons).", "The mobile ionic species are negatively charged oxygen ions.", "Continuing with the fuel cell operation, negative ions (anions) 28 migrate across the electrolyte 12 .", "The migrating anions 28 carry the negative charge to the electrolyte-anode interface.", "At the anode 14 , hydrogen 19 is oxidized.", "Because of hydrogen's affinity for oxygen, the hydrogen 19 flowing past the anode 14 is adsorbed by the anode 14 , where the hydrogen diffuses through the porous anode 14 to the anode-electrolyte interface, where as mentioned above, the hydrogen 19 is oxidized (loses electrons).", "The fuel cell unit 10 creates a flow of electrons 30 (electron flow).", "The flow of electrons 30 is conducted to an electrical load 32 via an electrical circuit (not shown).", "The electrical circuit maintains the flow of electrons 30 from the anode 14 to the electrical load 32 and continues to the cathode 16 .", "The electron flow 30 flows from the negative charge at the anode 14 to the positive charge at the cathode 16 .", "The electrical current (not shown), flows opposite the electron flow 30 from a high electrical potential at the cathode 16 to a low electrical potential at the anode 14 .", "In addition to electron flow 30 , the fuel cell produces reaction products from both electrodes while in operation.", "The anode reaction products 34 (product gases and depleted fuel, or combustion products) of the fuel cell unit 10 are typically water, carbon dioxide, hydrogen, carbon monoxide and other products, depending on the fuel 18 .", "Thermal energy is also a discharged product 34 .", "Cathode reaction products 36 (excess or depleted oxidant and product gases), typically air and water are also discharged.", "As stated previously, the fuel cell unit 10 , including the electrolyte 12 disposed between the anode 14 and the cathode 16 produces a limited quantity of electrical energy and thermal energy.", "Combining an individual fuel cell unit 10 with multiple fuel cell units 10 otherwise known as stacking, increases generating capacity amounting to a quantity of useful electrical and thermal energy.", "The serial array of individual fuel cell units 10 , creates a complete fuel cell 100 , (sometimes known as a fuel cell stack 102 ) (not shown).", "[0013] The electrochemical processes that occur in the fuel cell unit 10 can be related to the electrochemical processes that occur in the entire fuel cell 100 .", "The flow of electrons 30 from the fuel cell unit 10 is related to the sum of all electrons flowing 30 through the entire fuel cell 100 .", "The electrons flowing 30 through the fuel cell 100 are related to an electrical potential of fuel cell 100 .", "Electrical potential is measured as voltage.", "The voltage of the fuel cell 100 is a strong function of the concentration of the hydrogen 19 (fuel 18 ) in the feed stream of fuel of fuel cell 100 .", "Likewise, the voltage of the fuel cell unit 10 is a strong function of the concentration of the hydrogen 19 (fuel 18 ) in the feed stream of fuel to the fuel cell unit 10 .", "Stated another way, the concentration of the hydrogen in the fuel cell 100 is related to the flow of electrons 30 and to the electrical load 32 .", "The operability of the fuel cell 100 is related to the concentration of fuel 18 in the fuel cell 100 .", "Throughout the operation of the fuel cell 100 , the concentration of fuel 18 , is a parameter that indicates SOFC system performance.", "In a preferred embodiment, the concentration of hydrogen is a parameter that is used to optimize the performance of the fuel cell 100 .", "More specifically, the knowledge of the concentration of the hydrogen in the fuel stream being presented to the stack of fuel cell units 10 is a parameter that can be used to optimize the performance of the system.", "It has been determined by the inventors herein that measured voltage of one or more fuel cell units can be repeatably and reliably correlated to a a concentration of reformate flowing in the fuel stream to the fuel cell.", "The relationship of the flow of electrons 30 to the concentration of hydrogen 19 allows for measurement of the concentration of hydrogen 19 indirectly by measuring the voltage of one or more fuel cell unit(s) 10 .", "The voltage measurement of even a single fuel cell is correlatable to the reformate concentration in the entire fuel cell 100 .", "[0014] Turning now to FIG. 2, an exemplary embodiment of a fuel cell based fuel concentration sensor 40 , hereinafter, sensor 40 , is shown.", "The fundamental electrochemical processes of the sensor 40 remains the same as the electrochemical processes of the fuel cell unit 10 regardless of the various cell geometries.", "FIG. 2, illustrates an arrangement of a preferred embodiment of a sensor 40 that directly measures the voltage of the fuel cell unit 10 and indirectly allows determination of the concentration of hydrogen in the fuel cell 100 .", "The sensor 40 has the same basic components and materials as the fuel cell unit 10 shown in FIG. 1, with the substitution of the electrical load 32 for an indicator 42 .", "The indicator 42 measures and indicates the voltage of the sensor 40 .", "The components of an individual fuel cell unit 10 or, in one embodiment, a portion of the fuel cell unit 10 is utilized as the sensor 40 .", "The sensor 40 is nestable with the fuel cell 100 .", "In an embodiment, multiple sensors 40 are disposed or nested within the fuel cell 100 .", "Sensors 40 can be intermittently disposed throughout the fuel cell 100 stack to provide an array of indications within the cell geometry.", "In certain fuel cell 100 geometries, the fuel cell units 10 may experience different operating conditions at different locations within the fuel cell 100 , so placement of individual sensors 40 in different locations within the stack is also contemplated.", "In the preferred embodiment, the sensor 40 is not electrically connected to other fuel cell units 10 in the stack of the fuel cell 100 .", "The sensor 40 is isolatable from the fuel cell 100 stack.", "The sensor 40 is not connected to the electrical load 32 .", "[0015] The sensor 40 has the material properties to function in the environment of the fuel cell unit 10 .", "A hydrogen concentration sensor made from the same materials as the fuel cell components can withstand the SOFC operating environment.", "In a preferred embodiment, the sensor 40 has the same electrolyte 12 materials, the same anode 14 materials and the same cathode 16 materials as an individual fuel cell unit 10 .", "The sensor 40 is capable of determining the high concentrations of fuel that are encountered in the fuel cell unit 10 .", "The capability to determine the relatively high concentrations is due to the proportional relationship of the voltage and the fuel concentration in the fuel cell unit 10 .", "In a preferred embodiment, the sensor 40 is compatible with the SOFC using hydrogen as a fuel, where the hydrogen has a wide range of concentrations.", "A hydrogen concentration sensor that is not limited to relatively small hydrogen concentrations can measure hydrogen concentrations within the SOFC.", "[0016] Measuring the voltage with the sensor 40 provides data which is correlatable to the hydrogen concentration in the fuel cell 100 because the voltage of the sensor is proportional to the concentration of hydrogen being presented to the fuel cell 100 .", "The indicator 42 , in one embodiment, can be used simply to provide the data taken from measuring the voltage.", "The data can then be used to correlate the voltage to the hydrogen concentration.", "In another embodiment, the indicator 42 can measure the voltage and correlate the data taken from the measurement into a hydrogen concentration in a display.", "Measuring the voltage of the sensor 40 enables monitoring hydrogen 19 concentrations or other fuel 18 concentrations in other embodiments.", "[0017] A comparison of the voltage measured in the electrically isolated sensor 40 to the total voltage of the electrically loaded fuel cell units 10 stacked in the fuel cell 100 is also considered in an alternate embodiment.", "A variety of fuel cell 100 performance characteristics can be assessed, such as contamination within the fuel cell unit 10 , aging, and fuel cell efficiency, by knowing the concentration of hydrogen in the fuel cell 100 .", "The fuel cell unit 10 fuel flow rates as well as electrical load 32 can be controlled more efficiently as a result of having the capability to detect the voltage of the sensor 40 and correlate a fuel concentration in the fuel cell 100 .", "It is contemplated that applying varying electrical loads 32 to the sensor 40 and measuring the output impedance of the sensor 40 thus determining a relationship of the concentration of reformate (fuel 18 ) with the output impedance of the sensor 40 .", "[0018] While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention.", "In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof.", "Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims." ]
BACKGROUND OF THE INVENTION [0001] 1 . Field of the Invention [0002] The invention relates to an interactive mortgage and loan information and real-time trading system. [0003] 2. Related Art [0004] In the art of mortgage loans and mortgage brokering, a relatively large amount of information must be exchanged to conduct a loan transaction, such as a new home mortgage loan. In attempting to obtain a competitive loan for the borrower, or in attempting to maintain competitive rates for lenders to offer loans, this relatively large amount of information must be collected, compared, evaluated, and disseminated to possible counterparties to the transaction. The major parties include the borrower (and/or an agent such as a mortgage broker) and the lender; other parties can include appraisal agents, regulatory agencies, mortgage insurance companies, and secondary mortgage market participants. [0005] In known practices, nearly all the information relating to a loan transaction is collected by hand, transmitted using paper applications, compared by human beings (whose responsibilities include loan evaluation, property appraisal, financial market evaluation, and setting of lending rates), and disseminated using paper “rate sheets” or similar advertising material. For example, a mortgage broker attempting to obtain a loan for a borrower might be required to interview that client, consult rate sheets from multiple lenders to determine appropriate lending programs which might be appropriate for that client, submit multiple applications (possibly on multiple different forms) to selected ones of those lenders, and await action on those applications before being able to advise that client. Similarly, a lender attempting to set lending rates might be required to examine the present interest rate market, determine the mix of qualified borrowers likely to apply, determine a set of lending programs and lending rates best suited to the market and the risk the lender is willing to bear, and periodically post rate sheets or similar advertising material to multiple mortgage brokers informing them of those lending programs and lending rates. Upon receiving a loan application, the lender might also be required to independently evaluate the creditworthiness of the borrower and the value of the underlying property. [0006] As all of these operations are presently performed by hand, initiating loan transactions is relatively expensive. Although some forms of automation are known, such as uniform credit scoring for loan applications and automatic generation of loan application documents, there are no known systems in the field of mortgage lending for is providing relatively automatic and widespread dissemination of loan application information or lending program information for automated comparison in real time. The fact that these operations are performed by hand, rather than with the aid of computer processing, also limits the flexibility of the parties to the transaction. For borrowers, it is relatively difficult to compare more than a relatively few lending programs. For lenders, it is relatively difficult to select anything but a relatively simple set of lending categories for prospective borrowers. It is also practically impossible for lenders to experiment with new products without broadcasting knowledge of those new products to a wide population, including their competitors. [0007] Accordingly, it would be advantageous to provide a method and system for automating loan applications, such as home mortgage loan applications, placing them up for bid by a plurality of potential lenders, and following those loans using a technique for managing such loan applications and bids. This advantage is achieved in an embodiment of the invention in which a database server maintains a database of pending loan applications and their statuses; each party to the loan can search and modify that database consistent with their role in the transaction, by requests to the server from a client device identified with their role. SUMMARY OF INVENTION [0008] The invention provides a method and system for trading loans in real time by making loan applications, such as home mortgage loan applications, and placing them up for bid by a plurality of potential lenders. A transaction server maintains a database of pending loan applications and their statuses; each party to the loan can search and modify that database consistent with their role in the transaction, by requests to the server from a client device identified with their role. [0009] In a preferred embodiment, brokers at a broker station can add loan applications, can review the status of loan applications entered by that broker, are notified of lender's bids on their loans, and can accept bids by lenders. Lenders at a lender station can search the database for particular desired types of loans, can sort selected loans by particular desired criteria, can bid on loan applications, and are notified when their bids are accepted. Broker stations, lender stations, and the transaction server can be coupled using multiple access methods, including internet, intranet, or dial-up or leased communication lines. [0010] The transaction server marks prospective loans in its database by a variety of identifiers which might be of interest to lenders, including a loan amount, property location, property appraisal, borrower credit information, and potential CRA qualification for the property. The transaction server computes information about prospective loans which might be of interest to lenders, such as loan-to-value ratios, qualifying credit scores, and income classification for potential CRA qualification of the loan. The transaction server provides exogenous information which might be of interest to lenders and brokers for pricing loans, such as public bond market and other interest rate market news, as well as computed information regarding the pool of loans, such as current and past low, average, and high rates for a variety of loans traded using the system. [0011] In a preferred embodiment, the transaction server provides for detecting substantially identical loan applications originated by the same broker, so as to prevent double applications for the same borrower, and also provides brokers and lenders each the capability for designating counterparties with whom they wish not to conduct business. The transaction server is also supported by administration client/server devices for maintaining consistency and integrity of the transactions and relationships between parties. BRIEF DESCRIPTION OF THE DRAWINGS [0012] FIG. 1 shows a block diagram of an interactive mortgage and loan information and real-time trading system. [0013] FIG. 2 shows a process flow diagram of operation of an interactive mortgage and loan information and real-time trading system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0014] In the following description, a preferred embodiment of the invention is described with regard to preferred process steps and data structures. Those skilled in the art would recognize after perusal of this application that embodiments of the invention can be implemented using general purpose switching processors or special purpose is switching processors or other circuits adapted to particular process steps and data structures described herein, and that implementation of the process steps and data structures described herein would not require undue experimentation or further invention. System Architecture [0015] FIG. 1 shows a block diagram of an interactive mortgage and loan information and real-time trading system. [0016] An interactive mortgage and loan information and trading system 100 includes a transaction server 110 , a set of broker stations 120 , a set of lender stations 130 , an administration client 150 , a set of system monitor stations 160 , a web server 170 , and a communication network 140 . (1) Transaction Server [0017] The transaction server 110 comprises a device or set of devices coupled to the network 140 , such as a general purpose processor operating under control of operating system and application software, and disposed to respond to messages from the broker stations 120 , the lender stations 130 , and the system monitor stations 160 , as described herein. In a preferred embodiment, the transaction server 110 can comprise a Unix server such as a Sun UltraSparc processor operating under control of the Solaris operating system. [0018] The transaction server 110 includes a trading system database 111 , a geographic database 112 , and a set of external interfaces 113 . The transaction server 110 is enters loan profiles into the trading system database 111 in response to requests from the broker stations 120 , searches the trading system database 111 in response to requests from the lender stations 130 , and modifies the trading system database 111 in response to changes in status for loan profiles stored therein. [0019] The trading system database 111 includes loan profiles and other information needed to support trading operations for loans, stored in a relational database accessed using a database server module. In a preferred embodiment, the relational database comprises an Oracle database, but in alternative embodiments the relational database may comprise another type of relational database, such as a Sybase database, or may comprise an object-oriented database or another type of database structure. [0020] The trading system database 111 includes information regarding each loan application and its status. Each loan application includes a loan profile, which comprises information about the prospective loan, a set of bids, each of which comprises an offer to make the loan from a particular lender, and a set of status information, which relates to the processing of the loan application using the system 100 . [0021] In a preferred embodiment, at least the following information is included for each loan profile: information about the loan, including—loan category (FHLMC, FNMA, Conduit, VA, FHA, or Other); loan amount; loan type, such as adjustable or fixed interest rate; loan duration information about the underlying property, including—property type, such as SFR (single family residence), 2 units, 3 units, or 4 units; property location, by street address, city, county, and state; seller's asking price; appraised value information about the borrower, including—income and assets, credit history, and any negative information about the borrower (such as bankruptcy filings or debt discharge dates, reports of late mortgage payments) [0025] The transaction server 110 computes some information for each loan application which might be of interest to lenders and enters that information in the trading system database 111 when the loan profile itself is entered. [0026] In a preferred embodiment, this computed information includes: computed information about the loan, including—LTV (loan to value), CLTV (combined loan to value); debt ratios (Front ratio and Back ratio) computed information about the property, including—its census tract, its MSA (Metropolitan Statistical Area); its qualification as being in an area with majority population belonging to ethnic minorities; the income classification for its MSA computed information about the borrower, including—combined income and combined debt for multiple borrowers; qualifying credit score; CRA qualification for the loan (responsive to the borrower's income, the median income for the property's census tract, and the median income for the property's MSA) [0030] The geographic database 112 includes a geocoded database accessed using a geographic database module. In a preferred embodiment, the geocoded database relates each property address to its corresponding census tract, and comprises information relating to each census tract, such as median income, used for computing possible CRA qualification for the loan. The transaction server 110 reads the geographic database 112 to determine information relating to the property. [0031] The external interfaces 113 include communication links to exogenous information and services, using the network 140 or other direct links. The transaction a server 110 uses the external interfaces 113 to obtain information relating to the interest rate markets, the borrower, or the property. [0032] In a preferred embodiment, these exogenous information and services include: credit agencies and credit information provided by them desktop underwriting systems MIDEX loan processing systems real estate appraisal systems mortgage insurance agencies and mortgage scores provided by them information sources for public market and other news, including—real time quotes for 10 year Treasury notes, 30 year Treasury bonds, DJIA (Dow Jones Industrial Average), and NSDQ (National Securities Dealers Quotes) [0040] In a preferred embodiment, the transaction server 110 includes a set of program modules. Each module is a set of software objects and/or program elements, a collectively having the ability to execute independently in a separate thread or logical chain of process execution. Each module can be executed as a separate logical server or using a separate physical device. However, for clients such as the broker stations 120 , the lender stations 130 , and the administrative stations 150 , the transaction server 110 operates as a single logical server available using the network 140 . [0041] In a preferred embodiment, the transaction server 110 includes the is following program modules: login module—This module is responsible for password checking, access control, and assignment of a particular program module to service the client. Each broker station 120 is serviced by a broker module, each lender station 130 is serviced by a lender module, and each administration station 150 is serviced by an administration module. In a preferred embodiment, the login module also implements a load management policy so as to distribute computing tasks among different server devices on the network 140 . broker module—This module handles all server-side application requirements of the broker station 120 . lender module—This module handles all server-side application requirements of the lender station 130 . administration module—This module handles all server-side application requirements of the administration station 150 . external interface modules—Each interface to an external loan origination package or loan documentation package coupleable to the transaction server 110 has its own corresponding external interface module, for converting incoming data to a format for communication with the respective application module or database (most interfaces require only one way communication to receive data from an external package). external service modules—Each external service has a module for communicating with that external service and for obtaining information in a format required by the external service. For example, one of the external service modules would be used to obtain credit scores and reports from credit reporting agencies (most external services require two way communication with an external agent or process). notification module—This module handles notification and electronic mail communication with the broker stations 120 and the lender stations 130 . database interface module—This module handles all interface requirements between application modules and the databases. For example, the database interface module manages (a) the number of simultaneous connections to the database such that the total number is maintained within applicable license agreements; and (b) any integrity problems in interactions between application modules and the databases. Thus, this module allows the Transaction Server to be connected to different types of databases such as relational databases or object-oriented databases. geoserver module—This module receives the address sent to the transaction server 110 , performs a query to the geographic database for any matches, evaluates any matches and prepares a query response to the broker station 120 . monitoring module—This module manages resource usage by other modules and by the entire system. system module—This module includes a collection of data objects and program elements for utility tasks such as printing, reporting, and audit trails. trading system database 111 —This database includes loan profile data from the broker stations 120 , computed data for those loan profiles, and other relevant data needed to support real-time trading (such as user profiles and access permission information). geographical database 112 —This database includes data based on that published by the U.S. Census Bureau and the U.S. Postal Service ZIP +4 directory files. [0043] In a preferred embodiment, the transaction server 110 can configure its program modules and change operating parameters dynamically while the system 100 is operating, by editing selected files having operating parameters used during operation of the system 100 . Thus, additional devices can be added into the network 140 to meet resource requirements of the system 100 . (2) Broker Stations [0044] Each of the broker stations 120 comprises a device or set of devices coupled to the network 140 , such as a general purpose processor operating under control of operating system and application software, and disposed to enter and process loan profiles, as described herein. In a preferred embodiment, one of the broker stations 120 can comprise a PC workstation such as an Intel Pentium processor operating under control of the Microsoft Windows 95 operating system. [0045] The broker station 120 operates under control of broker client software, which interacts using the network 140 with the transaction server 110 as described herein. The broker station 120 includes information input devices, such as a keyboard and mouse or other pointing device, and information output and presentation devices, such as a monitor and printer. [0046] As used herein, the term “broker” includes any person or entity fulfilling a role as a loan originator, not necessarily a loan broker or a mortgage broker. For example, the broker stations 120 could be used directly by prospective borrowers, by cooperatives thereof, or by certain classes of loan officers at lending institutions. [0047] A brokerage organization can use the broker station 120 so as to coordinate with the brokerage's organizational structure. For example, a loan processor or a is manager can enter and view loans on behalf of one or more brokers, either individually or simultaneously in one screen display. Typically, a loan processor would act on behalf of a small number of selected brokers, while a manager would act on behalf of all brokers possibly including himself or herself. [0048] A broker uses the broker station 120 to transmit loan profiles to the transaction server 110 (thus entering those loan profiles into the system 100 for processing), to review the status of those loan profiles as they are processed by the system 100 , to receive notification of bids on those loan profiles by lenders, to review bids by lenders, to accept or decline bids by lenders, and to communicate with other users of the system 100 . [0049] In a preferred embodiment, the broker station 120 makes connections to the transaction server 110 using the network 140 on an as-needed basis, so as to send messages to the transaction server 110 without excessive use of the network 140 . Thus, when the broker station 120 has a loan profile to transfer to the transaction server 110 , the broker station 120 makes the connection to the transaction server 110 using the network 140 at that time, rather than maintaining a connection to the transaction server 110 while the broker is composing or editing the loan profile information. [0050] The broker station 120 can also receive asynchronous communications from the transaction server 110 , such as in the event there are urgent communications or other information of immediate interest to the broker. For example, the broker can request the transaction server 110 to transmit messages to the broker station 120 whenever any loan profile receives a bid having specified criteria (the broker can set these criteria, or can request notification of all bids or of none). The broker station 120 can also receive electronic mail messages from other users of the system 100 , including other brokers, lenders, or other parties. [0051] The transaction server 110 can also broadcast events of interest to all broker stations 120 , lender stations 130 , other parties, or selected ones thereof. [0052] In a preferred embodiment, the broker station 120 includes a software interface to an existing loan package software element, so that brokers can use that existing loan package software element to prepare loan profiles and transmit those loan profiles to the transaction server 110 . (3) Lender Stations [0053] Each of the lender stations 130 comprises a device or set of devices coupled to the network 140 , such as a general purpose processor operating under control of operating system and application software, and disposed to process loan profiles, as described herein. In a preferred embodiment, one of the lender stations 130 can comprise a PC workstation such as an Intel Pentium processor operating under control of the Microsoft Windows 95 operating system. [0054] The lender station 130 operates under control of lender client software, which interacts using the network 140 with the transaction server 110 as described herein. The lender station 130 includes information input devices, such as a keyboard and mouse or other pointing device, and information output and presentation devices, such as a monitor and printer. [0055] As used herein, the term “lender” includes any person or entity fulfilling a role as a loan maker or loan purchaser, not necessarily an actual lending institution or officer thereof. [0056] A lender uses the lender station 130 to search the database for particular desired types of loans, to sort selected loans by particular desired criteria, to bid on loan applications, and to be notified when their bids are accepted. The lender at the lender station 130 can construct and store its own particular desired criteria, and retrieve and s reuse those stored criteria. The lender at the lender station 130 can also direct the transaction server 110 to actively search for its own particular desired criteria, and to notify the lender at the lender station 130 when any loans matching those criteria appear in the trading system database 111 . [0057] In a preferred embodiment, similar to the broker station 120 , the lender station 130 makes connections to the transaction server 110 using the network 140 on an as-needed basis, so as to send messages to the transaction server 110 without excessive use of the network 140 . [0058] Similar to the broker station 120 , the lender station 130 can also receive asynchronous communications from the transaction server 110 , such as in the event there are urgent communications or other information of immediate interest to the lender. Also similar to the broker station 120 , the lender station 130 can also receive electronic mail messages from other users of the system 100 , including brokers, other lenders, or other parties. [0059] Similar to the broker station 120 , the lender broker station 130 includes a software interface to an existing desktop underwriting software element, so that lenders can use that existing desktop underwriting software element to review loan profiles and decide whether or not to bid on those loan profiles. (4) Administration Station [0060] The administration client 150 comprises a device or set of devices coupled to the network 140 , such as a general purpose processor operating under control of operating system and application software, and disposed to process loan profiles, as described herein. In a preferred embodiment, the administration client 150 can comprise a PC workstation such as an Intel Pentium processor operating under control of the Microsoft Windows 95 operating system, or can comprise software operating on a processor used for the transaction server 110 . [0061] The administration client 150 operates under control of administration client software, which interacts using the network 140 with the transaction server 110 as described herein. The administration client 150 includes information input devices, such as a keyboard and mouse or other pointing device, and information output and presentation devices, such as a monitor and printer. [0062] As used herein, the term “administrator” includes any person or entity fulfilling a role as an administrator of the system 100 , not necessarily an official of any entity associated with administration or maintenance of the system 100 . [0063] An administrator uses the administration client 150 to monitor operation of the system 100 , to generate reports on operation of the system 100 , and to be notified of any alertable conditions of the system 100 . [0064] Information is collected by the administration client 150 and stored in the system 100 and used in support of trading, including the following: personal and organizational information about the parties (both brokers and lenders), including—organizational affiliation, address and telephone number for contact, delivery information, electronic mail address information about changes in relationship between any parties, including when a loan processor or lender representative enters or leaves any selected broker or lender organization This information is transmitted to the transaction server 110 so as to ensure integrity of trading operations. For example, the transaction server 110 can enable or disable passwords at appropriate times, and can track any loans affiliated with the parties after their change in organizational affiliation. modification of a selected loan profile at the request of a broker client 120 [0069] Information is available to the administrator at the administration client 150 information regarding performance of the system 100 , including the following: number of brokers using the system 100 number of lenders using the system 100 number of loan profiles processed over a specified period of time number of loan profiles stored in the trading system database 111 [0074] In a preferred embodiment, similar to the broker station 120 , the administration client 150 makes connections to the transaction server 110 using the network 140 on an as-needed basis, so as to send messages to the transaction server 110 without excessive use of the network 140 . [0075] Similar to the broker station 120 , the administration client 150 can also receive asynchronous communications from the transaction server 110 , such as in the event there are urgent communications or other information of immediate interest to the is administrator. Also similar to the broker station 120 , the administration client 150 can also receive electronic mail messages from other users of the system 100 , including brokers, lenders, or other parties. (5) System Monitor Station [0076] A set of system monitor stations 160 are coupled to the network 140 for remotely monitoring and controlling the state and usage of the transaction server 110 . An operator using one or more of the system monitor stations 160 is capable of starting or stopping one of the program modules of the transaction server 110 or other components of the system 100 . Each system monitor stations 160 provides visual display of the state and usage of the transaction server 110 , selected ones of its program modules, and the network 140 . (6) Web Server [0077] A web server 170 is coupled to the network 140 for maintaining and serving documents and other information used by brokers at the broker stations 120 , is lenders at the lender stations 130 , and administrators at the administrator stations 150 . In a preferred embodiment, the web server 170 includes the following information: due diligence information on brokers and lenders, made available only to authorized persons for review; loan documents deposited by brokers or lenders, to be forwarded or transmitted only to authorized persons; rules, regulations, and procedures for trading using the system 100 , made available to all authorized persons (7) Other System Elements [0081] The network 140 provides for communication between the transaction server 110 , the broker station 120 , the lender station 130 , and the administration station 150 , using messages as described herein and message protocols appropriate to transmission and reception of those messages. The network 140 includes a WAN (wide area network) such as the “Advantis” network available from IBM Corporation of Armonk, 11 New York. However, in alternative embodiments, the network 140 may use internet, intranet, dial-up telephone lines or leased communication lines, or some combination thereof. In a preferred embodiment, the network 140 uses duplicate communication lines between nodes, and provides for automated failover transparent to users. [0082] In a preferred embodiment, messages transmitted using the network are encrypted or use digital signatures or other security measures to verify their source and to assure that they are not tapped or forged by intruders. System Operation [0083] FIG. 2 shows a process flow diagram of operation of an interactive mortgage and loan information and real-time trading system. [0084] A method 200 of operation of the system 100 includes a plurality of flow points and process steps as described herein. [0085] At a flow point 210 , a prospective borrower desires to obtain a home mortgage loan or similar loan. [0086] At a step 221 , the borrower transmits prospective loan information regarding a prospective loan application to a mortgage broker, loan broker, or similar agent. In a preferred embodiment, the prospective loan information can be transmitted using an industry standard form for prospective loan information, such as a Form 1003 or Form 1008 . The prospective loan information can also be transmitted using a computer file prepared using an existing loan documentation or origination software package. [0087] At a step 222 , the broker at the broker station 120 logs in to the transaction server 110 and verifies that the broker station 120 is authorized to access the system 100 . In this step, the transaction server 110 transmits any access control data or other data needed to initialize the broker station 120 so as to customize it for access by that individual broker, loan processor, or broker manager. [0088] The broker can perform one of a set of functions using the broker station 120 , including the following: managing loan profiles, including—creating a loan profile and adding it to the 24 . trading system database 111 ; reviewing a loan profile already in the trading system database 111 ; altering or otherwise updating a loan profile already in the trading system database 111 managing loan portfolios, including—searching pending loan profiles for those with or without bids, or for those with accepted bids managing bids on loans, including—viewing bids on loan profiles, accepting bids, viewing accepted bids viewing market information, including—viewing real time market data, viewing other mortgage news feeds or other news feeds prequalifying borrowers, including—viewing interest rates available on the system 100 , such as the average interest rate, high interest rate, low interest rate, or median interest rate associated with selected loan profile information; viewing aggregate interest rates for the entire system 100 ; viewing lender activity in terms of number of lenders who have purchased selected types of loans managing lender selection, including—deselecting particular lenders so that those lenders do not see loan profiles from this broker station 120 ; reselecting particular lenders communicating with other users of the system 100 , including—electronic mail messages; paging password management, including password changes [0097] In a preferred embodiment, the system 100 allows hierarchical management of loans from the perspective of the loan originator. A loan processor is allowed to perform these functions on behalf of one or more selected brokers, but is not allowed to post a loan on the loan processor's own behalf. Brokers can delegate authority to loan processors to post loans, and can exclude or include authority to accept bids with that delegation of authority. A selected broker manager is allowed to perform these functions as well as to post loans on the manager's own behalf. Authorization as a broker, loan processor, or manager is performed in the step 222 during login. [0098] At a step 223 , the broker at the broker station 120 interactively enters data for the loan profile, optionally periodically or intermittently save that data, optionally edits that data, optionally validates that data for reasonable values at the broker station 120 , and when complete, prepares to transmit the completed loan profile to the transaction server 110 . [0099] At a step 224 , the broker at the broker station 120 optionally reviews financial market information and mortgage market information relevant to the loan profile. This allows the broker to set competitive asking prices for loan profiles. [0100] At a step 225 , the broker at the broker station 120 sets a selected asking price for the loan profile. [0101] At a step 226 , the broker station 120 transmits a loan profile to the transaction server 110 . The loan profile includes the prospective loan information, but the transaction server 110 does not identify the borrower or the broker to prospective lenders. [0102] At a step 227 , the transaction server 110 validates the information provided for each loan profile, such as determining whether there is in fact a property at the indicated property location and whether there is in fact a property of the indicated property type at the indicated property location. If the transaction server 110 determines that the information provided for the loan profile is not valid (to more than a trivial extent), the transaction server 110 responds to the broker station 120 by requesting correction. [0103] As part of the step 227 , the transaction server 110 or the broker station 120 can transform certain data entry values so as to make it convenient for the broker to enter data. For example, for loan amount, the transaction server 110 or the broker station 120 can accept the value “300K” and transform that to the value “300,000”. [0104] Also as part of the step 227 , the transaction server 110 provides for detecting substantially identical loan profiles originated by the same broker station 120 , so as to prevent multiple applications for the same borrower for the same property; this practice is sometimes known as “double apping”. [0105] At a step 228 , the transaction server 110 computes any computed information for the loan profile (including determining whether the loan profile is CRA eligible) and stores the loan profile in the trading system database 111 . [0106] At a step 229 , the transaction server 110 computes aggregate tags for the loan profile so as to respond to specialized lender queries, such as whether the loan profile is for a “prime” loan or a “subprime” loan or whether the loan profile is CRA eligible), and stores that information in the loan profile in the trading system database 111 . [0107] At a flow point 230 , a prospective lender desires to bid on one or more loan applications. [0108] At a step 241 , the lender at the lender station 130 logs in to the transaction server 110 and verifies that the lender station 130 is authorized to access the system 100 . [0109] In a preferred embodiment, selected lenders are allowed to access selected categories of loan profiles depending on the nature of their membership or privileges granted to them when signing up for using the system 100 . For example, selected portions of the lender's ability to query the trading system database 111 can depend on the level of service the lender requested when signing up for the system 100 . As part of the step 241 , this information is transmitted by the transaction server 110 to the lender station 130 upon verification of the lender station 130 . [0110] The lender can perform one of a set of functions using the lender station 130 , including the following: managing loan profile searches, including—defining loan profile searches, storing loan profile searches for later use or reuse, directing the transaction server 110 to perform a loan profile search Loan profile searches can specify that the loan profile can be considered for community investment purposes or is CRA qualified. Loan profile searches can also be specified to be “active,” in which the transaction server 110 is directed to periodically perform the loan profile search on updated contents of the trading system database 111 , and to notify the lender station 130 of revised results of the active loan profile search. managing search results, including—viewing results of a loan profile search managing bids on loans, including—placing bids on loan profiles, receiving notification of accepted bids The transaction server 110 provides limited information to this particular lender station 130 on bids placed by other lender stations 130 . In the case that this particular lender station 130 had the winning bid, the next best bid is provided for display; in the case that this particular lender station 130 had its bid rejected, the winning bid is provided for display. managing loan portfolios, including—searching loan profiles for accepted bids; searching loan profiles for selected status of loan processing; viewing particular loan profiles for bid or processing status viewing market information, including—viewing real time market data, viewing other mortgage news feeds or other news feeds managing broker selection, including—deselecting particular brokers so that loan profiles from those brokers are not found by loan profile searches from this lender station 130 ; reselecting particular brokers; viewing due diligence information on particular brokers communicating with other users of the system 100 , including—electronic mail messages; paging password management, including—password changes [0122] At a step 242 , the lender at the lender station 130 determines a query profile for querying the database, depending on the loan programs available to the lender at that time. In a preferred embodiment, the lender station 130 optionally stores the query profiles, so that the lender can optionally use or modify a query profile for reuse. [0123] At a step 243 , the lender at the lender station 130 transmits a database s query to the transaction server, requesting loan profiles regarding prospective loans which might be of interest to the lender. As part of the query, the lender can choose to retrieve only those loans on which the lender has not already bid, or to retrieve all such a loans regardless of their bid status. [0124] Although the lender is not informed of the identity of the borrower, the lender can query for searchable database elements relating to the borrower. For example, the lender can search on criteria such as the following: loan category (FHLMC, FNMA, Conduit, VA, FHA, Other); loan type (adjustable or fixed interest rate); amortization time; loan purpose (new purchase, improvement); occupancy status calculated credit information for the loan, such as a LTV (loan to value) ratio, a qualifying credit score, front and back ratios, loan lock period, a total loan amount, whether the loan is “conforming” particular qualifying credit information regarding the borrower, such as gross family income, other outstanding debts, or credit history reports particular credit information regarding the property, such as its nature (raw land, condominium, detached single family home, apartment less than four units, income property), its location (census tract, zip code, city, county, state), and whether it qualifies for CRA (Community Reinvestment Act) credit for the lender particular credit information regarding the broker, such as a history of loan qualification or loan performance for loans originating with that broker [0129] At a step 244 , the transaction server 110 performs a database lookup for the trading system database 111 in response to the database query, and transmits a query response to the lender station 130 . The query response identifies loan profiles which match the database query. [0130] At a step 245 , the transaction server 110 transmits information regarding is loan profiles matching the query to the lender station 130 . In a preferred embodiment, loans already bid upon by the lender are so marked, such as by being displayed in a different color. [0131] At a step 246 , the lender at the lender station 130 can view details of the loan profile interactively. In a preferred embodiment, the lender's attention is drawn by marking selected loan profiles, such as by being displayed in a different color. Selected loan profiles can include those having comments regarding the nature of the property or qualifying qualitative remarks. [0132] At a step 247 , the lender at the lender station 130 optionally reviews the lender's portfolio of those loans with accepted or rejected bids and those loans waiting for responses from brokers at broker stations 120 . The lender at the lender station 130 optionally reviews the lender's bids declined by brokers at broker stations 120 against winning bids, and optionally reviews the lender's winning bids against others' bids declined by brokers at broker stations 120 . The lender at the lender station 130 optionally reviews market performance, including activity in the system 100 . [0133] At a step 248 , the lender at the lender station 130 selects a loan profile for bid and optionally requests details of that selected loan profile; in response, the transaction server 110 transmits details about the loan profiles to the lender station 130 . [0134] At a step 249 , the lender at the lender station 130 transmits a bid on one of the loan profiles. The transaction server 110 enters the bid in the loan profile, indicating that the lender has bid on the loan profile, but does not identify the lender to prospective borrowers or brokers. [0135] The bid can have an associated expiration time, after which the transaction server 110 will mark the bid withdrawn (or delete it), so that it can no longer be accepted. [0136] In a preferred embodiment, the lender at the lender station 130 can post a single common bid for multiple loan profiles. [0137] At a step 250 , the transaction server 110 transmits a bid notification to each broker station 120 associated with a loan profile which has received a bid. The bid notification can include one or more of the following: (a) a bid alert on a display at the broker station 120 , (b) a pager notification to the broker; (c) an electronic mail message to the broker station 120 . [0138] At a flow point 260 , a prospective borrower desires to accept a bid on a loan application. [0139] At a step 271 , the broker at the broker station 120 logs in to the transaction server 110 and verifies that the broker station 120 is authorized to access the system 100 and is authorized to accept bids for that broker. [0140] At a step 272 , the broker at the broker station 120 optionally reviews the broker's portfolio of those loans with accepted bids, those loans with pending unaccepted bids, and those loans waiting for bids from lenders at lender stations 130 . The broker at the lender station 130 optionally reviews market performance, including activity in the system 100 . [0141] At a step 273 , the broker at the broker station 120 selects a loan profile with pending unaccepted bids and optionally requests details of that selected loan profile; in response, the transaction server 110 transmits details about the loan profiles to the broker station 120 . The broker at the broker station 120 selects one or more pending bids for that loan profile and optionally requests details about those bids; in response, the transaction server 110 transmits details about the pending bids to the broker station 120 . [0142] At a step 274 , the broker station 120 transmits an acceptance, for a particular bid for a particular loan profile, to the transaction server 110 . The transaction server 110 marks that bid at the loan profile as having been accepted, and marks all other bids at the loan profile as having been rejected. [0143] At a step 275 , the transaction server 110 notifies the winning bidder lender of the bid acceptance. [0144] At a step 276 , the transaction server 110 transmits complete prospective loan information to the lender at the lender station 130 and complete lender information to the broker at the broker station 120 , thus informing the borrower of the identity of the lender and informing the lender of the identity of the borrower. [0145] Although the lender at the lender station 130 is not informed of the identity of the broker associated with the loan profile until the bid is accepted, the lender at the lender station 130 can select broker stations 120 for identification as being undesirable, so that loan profiles from those broker stations 120 are not transmitted in the query response. Similarly, although the broker at the broker station 120 is not informed of the identity of the lender associated with the bid, the broker at the broker station 120 can select lender stations 130 for identification as being undesirable, so that bids from those lender stations 130 are not displayed in the loan profile (and the broker station 120 is not notified of receipt of bids from those lender stations 130 ). [0146] At a step 277 , the broker transmits, either on paper or by EDI (electronic data interchange), a complete loan application package in a format acceptable to the particular lender. After verification of the prospective loan information or other formalities, the lender completes the loan. [0147] The broker at the broker station 120 can also prequalify prospective borrowers or a prospective loan profile so as to determine feasibility for a particular loan or a particular loan amount. [0148] At a flow point 280 , a broker desires to prequalify a prospective borrower. [0149] At a step 291 , the broker at the broker station 120 logs in to the transaction server 110 and verifies that the broker station 120 is authorized to access the system 100 . [0150] At a step 292 , the transaction server 110 transmits to the broker station 120 , and the broker station 120 initializes, search criteria for prequalification with a set of loan products available from lenders at lender stations 130 or otherwise tradeable on the system 100 . [0151] At a step 293 , the broker at the broker station 120 enters preliminary information regarding the prospective borrower, such as—expected credit score, and expected front ratio, back ratio, and LTV ratio. The broker at the broker station 120 can enter information regarding points or rates, and obtain current and past corresponding points or rates; for example, the broker at the broker station 120 can enter a selected interest rate and obtain the average, high, and low values for points corresponding to that interest rate for completed loan transactions on the system 100 . The broker at the broker station 120 can also determine statistics regarding how many lenders have made loans of those types. [0152] At a step 294 , the broker at the broker station 120 can inform the prospective borrower about whether or not it is feasible to obtain competitive rates in those contemplated ranges. [0153] The transaction server 110 records information regarding pending loan profiles and completed loans for later monitoring and reporting by the administrative client 150 . In a preferred embodiment, this information includes at least the following: an audit trail of all actions taken with regard to each particular loan profile, including all transaction data associated with the loan profile for future verification. a record of loan performance for loan profiles which have been processed using the system 100 , including a database of loan performance searchable by various criteria [0156] In a preferred embodiment, the borrower and the lender are each charged a fee for the service provided by the transaction server. The fee is paid out of escrow funds by a selected escrow company when the loan and an associated purchase of the property are completed. The amount of the fee can be fixed or can be varied in response to the prospective loan information, such as the amount of the loan, and in a preferred embodiment is varied in response to CRA qualification for the loan. Alternative Embodiments [0157] Although preferred embodiments are disclosed herein, many variations are possible which remain within the concept, scope, and spirit of the invention, and these variations would become clear to those skilled in the art after perusal of this application.
The invention provides a method and system for trading loans in real time. Loan applications, such as home mortgage loan applications, are made available electronically to receive bids from a plurality of potential lenders. A transaction server maintains a database of pending loan applications and their statuses, which is accessible over a communications channel, such as the Internet. Each party to a loan can search and modify the database consistent with their role in a transaction. The invention provides smart computerized administration that ensures personal preferences of the participating parties are enforced, errors and duplication is avoided, and information relating to accumulated data is available to the parties consistent with their roles.
Provide a concise summary of the essential information conveyed in the context.
[ "BACKGROUND OF THE INVENTION [0001] 1 .", "Field of the Invention [0002] The invention relates to an interactive mortgage and loan information and real-time trading system.", "[0003] 2.", "Related Art [0004] In the art of mortgage loans and mortgage brokering, a relatively large amount of information must be exchanged to conduct a loan transaction, such as a new home mortgage loan.", "In attempting to obtain a competitive loan for the borrower, or in attempting to maintain competitive rates for lenders to offer loans, this relatively large amount of information must be collected, compared, evaluated, and disseminated to possible counterparties to the transaction.", "The major parties include the borrower (and/or an agent such as a mortgage broker) and the lender;", "other parties can include appraisal agents, regulatory agencies, mortgage insurance companies, and secondary mortgage market participants.", "[0005] In known practices, nearly all the information relating to a loan transaction is collected by hand, transmitted using paper applications, compared by human beings (whose responsibilities include loan evaluation, property appraisal, financial market evaluation, and setting of lending rates), and disseminated using paper “rate sheets”", "or similar advertising material.", "For example, a mortgage broker attempting to obtain a loan for a borrower might be required to interview that client, consult rate sheets from multiple lenders to determine appropriate lending programs which might be appropriate for that client, submit multiple applications (possibly on multiple different forms) to selected ones of those lenders, and await action on those applications before being able to advise that client.", "Similarly, a lender attempting to set lending rates might be required to examine the present interest rate market, determine the mix of qualified borrowers likely to apply, determine a set of lending programs and lending rates best suited to the market and the risk the lender is willing to bear, and periodically post rate sheets or similar advertising material to multiple mortgage brokers informing them of those lending programs and lending rates.", "Upon receiving a loan application, the lender might also be required to independently evaluate the creditworthiness of the borrower and the value of the underlying property.", "[0006] As all of these operations are presently performed by hand, initiating loan transactions is relatively expensive.", "Although some forms of automation are known, such as uniform credit scoring for loan applications and automatic generation of loan application documents, there are no known systems in the field of mortgage lending for is providing relatively automatic and widespread dissemination of loan application information or lending program information for automated comparison in real time.", "The fact that these operations are performed by hand, rather than with the aid of computer processing, also limits the flexibility of the parties to the transaction.", "For borrowers, it is relatively difficult to compare more than a relatively few lending programs.", "For lenders, it is relatively difficult to select anything but a relatively simple set of lending categories for prospective borrowers.", "It is also practically impossible for lenders to experiment with new products without broadcasting knowledge of those new products to a wide population, including their competitors.", "[0007] Accordingly, it would be advantageous to provide a method and system for automating loan applications, such as home mortgage loan applications, placing them up for bid by a plurality of potential lenders, and following those loans using a technique for managing such loan applications and bids.", "This advantage is achieved in an embodiment of the invention in which a database server maintains a database of pending loan applications and their statuses;", "each party to the loan can search and modify that database consistent with their role in the transaction, by requests to the server from a client device identified with their role.", "SUMMARY OF INVENTION [0008] The invention provides a method and system for trading loans in real time by making loan applications, such as home mortgage loan applications, and placing them up for bid by a plurality of potential lenders.", "A transaction server maintains a database of pending loan applications and their statuses;", "each party to the loan can search and modify that database consistent with their role in the transaction, by requests to the server from a client device identified with their role.", "[0009] In a preferred embodiment, brokers at a broker station can add loan applications, can review the status of loan applications entered by that broker, are notified of lender's bids on their loans, and can accept bids by lenders.", "Lenders at a lender station can search the database for particular desired types of loans, can sort selected loans by particular desired criteria, can bid on loan applications, and are notified when their bids are accepted.", "Broker stations, lender stations, and the transaction server can be coupled using multiple access methods, including internet, intranet, or dial-up or leased communication lines.", "[0010] The transaction server marks prospective loans in its database by a variety of identifiers which might be of interest to lenders, including a loan amount, property location, property appraisal, borrower credit information, and potential CRA qualification for the property.", "The transaction server computes information about prospective loans which might be of interest to lenders, such as loan-to-value ratios, qualifying credit scores, and income classification for potential CRA qualification of the loan.", "The transaction server provides exogenous information which might be of interest to lenders and brokers for pricing loans, such as public bond market and other interest rate market news, as well as computed information regarding the pool of loans, such as current and past low, average, and high rates for a variety of loans traded using the system.", "[0011] In a preferred embodiment, the transaction server provides for detecting substantially identical loan applications originated by the same broker, so as to prevent double applications for the same borrower, and also provides brokers and lenders each the capability for designating counterparties with whom they wish not to conduct business.", "The transaction server is also supported by administration client/server devices for maintaining consistency and integrity of the transactions and relationships between parties.", "BRIEF DESCRIPTION OF THE DRAWINGS [0012] FIG. 1 shows a block diagram of an interactive mortgage and loan information and real-time trading system.", "[0013] FIG. 2 shows a process flow diagram of operation of an interactive mortgage and loan information and real-time trading system.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0014] In the following description, a preferred embodiment of the invention is described with regard to preferred process steps and data structures.", "Those skilled in the art would recognize after perusal of this application that embodiments of the invention can be implemented using general purpose switching processors or special purpose is switching processors or other circuits adapted to particular process steps and data structures described herein, and that implementation of the process steps and data structures described herein would not require undue experimentation or further invention.", "System Architecture [0015] FIG. 1 shows a block diagram of an interactive mortgage and loan information and real-time trading system.", "[0016] An interactive mortgage and loan information and trading system 100 includes a transaction server 110 , a set of broker stations 120 , a set of lender stations 130 , an administration client 150 , a set of system monitor stations 160 , a web server 170 , and a communication network 140 .", "(1) Transaction Server [0017] The transaction server 110 comprises a device or set of devices coupled to the network 140 , such as a general purpose processor operating under control of operating system and application software, and disposed to respond to messages from the broker stations 120 , the lender stations 130 , and the system monitor stations 160 , as described herein.", "In a preferred embodiment, the transaction server 110 can comprise a Unix server such as a Sun UltraSparc processor operating under control of the Solaris operating system.", "[0018] The transaction server 110 includes a trading system database 111 , a geographic database 112 , and a set of external interfaces 113 .", "The transaction server 110 is enters loan profiles into the trading system database 111 in response to requests from the broker stations 120 , searches the trading system database 111 in response to requests from the lender stations 130 , and modifies the trading system database 111 in response to changes in status for loan profiles stored therein.", "[0019] The trading system database 111 includes loan profiles and other information needed to support trading operations for loans, stored in a relational database accessed using a database server module.", "In a preferred embodiment, the relational database comprises an Oracle database, but in alternative embodiments the relational database may comprise another type of relational database, such as a Sybase database, or may comprise an object-oriented database or another type of database structure.", "[0020] The trading system database 111 includes information regarding each loan application and its status.", "Each loan application includes a loan profile, which comprises information about the prospective loan, a set of bids, each of which comprises an offer to make the loan from a particular lender, and a set of status information, which relates to the processing of the loan application using the system 100 .", "[0021] In a preferred embodiment, at least the following information is included for each loan profile: information about the loan, including—loan category (FHLMC, FNMA, Conduit, VA, FHA, or Other);", "loan amount;", "loan type, such as adjustable or fixed interest rate;", "loan duration information about the underlying property, including—property type, such as SFR (single family residence), 2 units, 3 units, or 4 units;", "property location, by street address, city, county, and state;", "seller's asking price;", "appraised value information about the borrower, including—income and assets, credit history, and any negative information about the borrower (such as bankruptcy filings or debt discharge dates, reports of late mortgage payments) [0025] The transaction server 110 computes some information for each loan application which might be of interest to lenders and enters that information in the trading system database 111 when the loan profile itself is entered.", "[0026] In a preferred embodiment, this computed information includes: computed information about the loan, including—LTV (loan to value), CLTV (combined loan to value);", "debt ratios (Front ratio and Back ratio) computed information about the property, including—its census tract, its MSA (Metropolitan Statistical Area);", "its qualification as being in an area with majority population belonging to ethnic minorities;", "the income classification for its MSA computed information about the borrower, including—combined income and combined debt for multiple borrowers;", "qualifying credit score;", "CRA qualification for the loan (responsive to the borrower's income, the median income for the property's census tract, and the median income for the property's MSA) [0030] The geographic database 112 includes a geocoded database accessed using a geographic database module.", "In a preferred embodiment, the geocoded database relates each property address to its corresponding census tract, and comprises information relating to each census tract, such as median income, used for computing possible CRA qualification for the loan.", "The transaction server 110 reads the geographic database 112 to determine information relating to the property.", "[0031] The external interfaces 113 include communication links to exogenous information and services, using the network 140 or other direct links.", "The transaction a server 110 uses the external interfaces 113 to obtain information relating to the interest rate markets, the borrower, or the property.", "[0032] In a preferred embodiment, these exogenous information and services include: credit agencies and credit information provided by them desktop underwriting systems MIDEX loan processing systems real estate appraisal systems mortgage insurance agencies and mortgage scores provided by them information sources for public market and other news, including—real time quotes for 10 year Treasury notes, 30 year Treasury bonds, DJIA (Dow Jones Industrial Average), and NSDQ (National Securities Dealers Quotes) [0040] In a preferred embodiment, the transaction server 110 includes a set of program modules.", "Each module is a set of software objects and/or program elements, a collectively having the ability to execute independently in a separate thread or logical chain of process execution.", "Each module can be executed as a separate logical server or using a separate physical device.", "However, for clients such as the broker stations 120 , the lender stations 130 , and the administrative stations 150 , the transaction server 110 operates as a single logical server available using the network 140 .", "[0041] In a preferred embodiment, the transaction server 110 includes the is following program modules: login module—This module is responsible for password checking, access control, and assignment of a particular program module to service the client.", "Each broker station 120 is serviced by a broker module, each lender station 130 is serviced by a lender module, and each administration station 150 is serviced by an administration module.", "In a preferred embodiment, the login module also implements a load management policy so as to distribute computing tasks among different server devices on the network 140 .", "broker module—This module handles all server-side application requirements of the broker station 120 .", "lender module—This module handles all server-side application requirements of the lender station 130 .", "administration module—This module handles all server-side application requirements of the administration station 150 .", "external interface modules—Each interface to an external loan origination package or loan documentation package coupleable to the transaction server 110 has its own corresponding external interface module, for converting incoming data to a format for communication with the respective application module or database (most interfaces require only one way communication to receive data from an external package).", "external service modules—Each external service has a module for communicating with that external service and for obtaining information in a format required by the external service.", "For example, one of the external service modules would be used to obtain credit scores and reports from credit reporting agencies (most external services require two way communication with an external agent or process).", "notification module—This module handles notification and electronic mail communication with the broker stations 120 and the lender stations 130 .", "database interface module—This module handles all interface requirements between application modules and the databases.", "For example, the database interface module manages (a) the number of simultaneous connections to the database such that the total number is maintained within applicable license agreements;", "and (b) any integrity problems in interactions between application modules and the databases.", "Thus, this module allows the Transaction Server to be connected to different types of databases such as relational databases or object-oriented databases.", "geoserver module—This module receives the address sent to the transaction server 110 , performs a query to the geographic database for any matches, evaluates any matches and prepares a query response to the broker station 120 .", "monitoring module—This module manages resource usage by other modules and by the entire system.", "system module—This module includes a collection of data objects and program elements for utility tasks such as printing, reporting, and audit trails.", "trading system database 111 —This database includes loan profile data from the broker stations 120 , computed data for those loan profiles, and other relevant data needed to support real-time trading (such as user profiles and access permission information).", "geographical database 112 —This database includes data based on that published by the U.S. Census Bureau and the U.S. Postal Service ZIP +4 directory files.", "[0043] In a preferred embodiment, the transaction server 110 can configure its program modules and change operating parameters dynamically while the system 100 is operating, by editing selected files having operating parameters used during operation of the system 100 .", "Thus, additional devices can be added into the network 140 to meet resource requirements of the system 100 .", "(2) Broker Stations [0044] Each of the broker stations 120 comprises a device or set of devices coupled to the network 140 , such as a general purpose processor operating under control of operating system and application software, and disposed to enter and process loan profiles, as described herein.", "In a preferred embodiment, one of the broker stations 120 can comprise a PC workstation such as an Intel Pentium processor operating under control of the Microsoft Windows 95 operating system.", "[0045] The broker station 120 operates under control of broker client software, which interacts using the network 140 with the transaction server 110 as described herein.", "The broker station 120 includes information input devices, such as a keyboard and mouse or other pointing device, and information output and presentation devices, such as a monitor and printer.", "[0046] As used herein, the term “broker”", "includes any person or entity fulfilling a role as a loan originator, not necessarily a loan broker or a mortgage broker.", "For example, the broker stations 120 could be used directly by prospective borrowers, by cooperatives thereof, or by certain classes of loan officers at lending institutions.", "[0047] A brokerage organization can use the broker station 120 so as to coordinate with the brokerage's organizational structure.", "For example, a loan processor or a is manager can enter and view loans on behalf of one or more brokers, either individually or simultaneously in one screen display.", "Typically, a loan processor would act on behalf of a small number of selected brokers, while a manager would act on behalf of all brokers possibly including himself or herself.", "[0048] A broker uses the broker station 120 to transmit loan profiles to the transaction server 110 (thus entering those loan profiles into the system 100 for processing), to review the status of those loan profiles as they are processed by the system 100 , to receive notification of bids on those loan profiles by lenders, to review bids by lenders, to accept or decline bids by lenders, and to communicate with other users of the system 100 .", "[0049] In a preferred embodiment, the broker station 120 makes connections to the transaction server 110 using the network 140 on an as-needed basis, so as to send messages to the transaction server 110 without excessive use of the network 140 .", "Thus, when the broker station 120 has a loan profile to transfer to the transaction server 110 , the broker station 120 makes the connection to the transaction server 110 using the network 140 at that time, rather than maintaining a connection to the transaction server 110 while the broker is composing or editing the loan profile information.", "[0050] The broker station 120 can also receive asynchronous communications from the transaction server 110 , such as in the event there are urgent communications or other information of immediate interest to the broker.", "For example, the broker can request the transaction server 110 to transmit messages to the broker station 120 whenever any loan profile receives a bid having specified criteria (the broker can set these criteria, or can request notification of all bids or of none).", "The broker station 120 can also receive electronic mail messages from other users of the system 100 , including other brokers, lenders, or other parties.", "[0051] The transaction server 110 can also broadcast events of interest to all broker stations 120 , lender stations 130 , other parties, or selected ones thereof.", "[0052] In a preferred embodiment, the broker station 120 includes a software interface to an existing loan package software element, so that brokers can use that existing loan package software element to prepare loan profiles and transmit those loan profiles to the transaction server 110 .", "(3) Lender Stations [0053] Each of the lender stations 130 comprises a device or set of devices coupled to the network 140 , such as a general purpose processor operating under control of operating system and application software, and disposed to process loan profiles, as described herein.", "In a preferred embodiment, one of the lender stations 130 can comprise a PC workstation such as an Intel Pentium processor operating under control of the Microsoft Windows 95 operating system.", "[0054] The lender station 130 operates under control of lender client software, which interacts using the network 140 with the transaction server 110 as described herein.", "The lender station 130 includes information input devices, such as a keyboard and mouse or other pointing device, and information output and presentation devices, such as a monitor and printer.", "[0055] As used herein, the term “lender”", "includes any person or entity fulfilling a role as a loan maker or loan purchaser, not necessarily an actual lending institution or officer thereof.", "[0056] A lender uses the lender station 130 to search the database for particular desired types of loans, to sort selected loans by particular desired criteria, to bid on loan applications, and to be notified when their bids are accepted.", "The lender at the lender station 130 can construct and store its own particular desired criteria, and retrieve and s reuse those stored criteria.", "The lender at the lender station 130 can also direct the transaction server 110 to actively search for its own particular desired criteria, and to notify the lender at the lender station 130 when any loans matching those criteria appear in the trading system database 111 .", "[0057] In a preferred embodiment, similar to the broker station 120 , the lender station 130 makes connections to the transaction server 110 using the network 140 on an as-needed basis, so as to send messages to the transaction server 110 without excessive use of the network 140 .", "[0058] Similar to the broker station 120 , the lender station 130 can also receive asynchronous communications from the transaction server 110 , such as in the event there are urgent communications or other information of immediate interest to the lender.", "Also similar to the broker station 120 , the lender station 130 can also receive electronic mail messages from other users of the system 100 , including brokers, other lenders, or other parties.", "[0059] Similar to the broker station 120 , the lender broker station 130 includes a software interface to an existing desktop underwriting software element, so that lenders can use that existing desktop underwriting software element to review loan profiles and decide whether or not to bid on those loan profiles.", "(4) Administration Station [0060] The administration client 150 comprises a device or set of devices coupled to the network 140 , such as a general purpose processor operating under control of operating system and application software, and disposed to process loan profiles, as described herein.", "In a preferred embodiment, the administration client 150 can comprise a PC workstation such as an Intel Pentium processor operating under control of the Microsoft Windows 95 operating system, or can comprise software operating on a processor used for the transaction server 110 .", "[0061] The administration client 150 operates under control of administration client software, which interacts using the network 140 with the transaction server 110 as described herein.", "The administration client 150 includes information input devices, such as a keyboard and mouse or other pointing device, and information output and presentation devices, such as a monitor and printer.", "[0062] As used herein, the term “administrator”", "includes any person or entity fulfilling a role as an administrator of the system 100 , not necessarily an official of any entity associated with administration or maintenance of the system 100 .", "[0063] An administrator uses the administration client 150 to monitor operation of the system 100 , to generate reports on operation of the system 100 , and to be notified of any alertable conditions of the system 100 .", "[0064] Information is collected by the administration client 150 and stored in the system 100 and used in support of trading, including the following: personal and organizational information about the parties (both brokers and lenders), including—organizational affiliation, address and telephone number for contact, delivery information, electronic mail address information about changes in relationship between any parties, including when a loan processor or lender representative enters or leaves any selected broker or lender organization This information is transmitted to the transaction server 110 so as to ensure integrity of trading operations.", "For example, the transaction server 110 can enable or disable passwords at appropriate times, and can track any loans affiliated with the parties after their change in organizational affiliation.", "modification of a selected loan profile at the request of a broker client 120 [0069] Information is available to the administrator at the administration client 150 information regarding performance of the system 100 , including the following: number of brokers using the system 100 number of lenders using the system 100 number of loan profiles processed over a specified period of time number of loan profiles stored in the trading system database 111 [0074] In a preferred embodiment, similar to the broker station 120 , the administration client 150 makes connections to the transaction server 110 using the network 140 on an as-needed basis, so as to send messages to the transaction server 110 without excessive use of the network 140 .", "[0075] Similar to the broker station 120 , the administration client 150 can also receive asynchronous communications from the transaction server 110 , such as in the event there are urgent communications or other information of immediate interest to the is administrator.", "Also similar to the broker station 120 , the administration client 150 can also receive electronic mail messages from other users of the system 100 , including brokers, lenders, or other parties.", "(5) System Monitor Station [0076] A set of system monitor stations 160 are coupled to the network 140 for remotely monitoring and controlling the state and usage of the transaction server 110 .", "An operator using one or more of the system monitor stations 160 is capable of starting or stopping one of the program modules of the transaction server 110 or other components of the system 100 .", "Each system monitor stations 160 provides visual display of the state and usage of the transaction server 110 , selected ones of its program modules, and the network 140 .", "(6) Web Server [0077] A web server 170 is coupled to the network 140 for maintaining and serving documents and other information used by brokers at the broker stations 120 , is lenders at the lender stations 130 , and administrators at the administrator stations 150 .", "In a preferred embodiment, the web server 170 includes the following information: due diligence information on brokers and lenders, made available only to authorized persons for review;", "loan documents deposited by brokers or lenders, to be forwarded or transmitted only to authorized persons;", "rules, regulations, and procedures for trading using the system 100 , made available to all authorized persons (7) Other System Elements [0081] The network 140 provides for communication between the transaction server 110 , the broker station 120 , the lender station 130 , and the administration station 150 , using messages as described herein and message protocols appropriate to transmission and reception of those messages.", "The network 140 includes a WAN (wide area network) such as the “Advantis”", "network available from IBM Corporation of Armonk, 11 New York.", "However, in alternative embodiments, the network 140 may use internet, intranet, dial-up telephone lines or leased communication lines, or some combination thereof.", "In a preferred embodiment, the network 140 uses duplicate communication lines between nodes, and provides for automated failover transparent to users.", "[0082] In a preferred embodiment, messages transmitted using the network are encrypted or use digital signatures or other security measures to verify their source and to assure that they are not tapped or forged by intruders.", "System Operation [0083] FIG. 2 shows a process flow diagram of operation of an interactive mortgage and loan information and real-time trading system.", "[0084] A method 200 of operation of the system 100 includes a plurality of flow points and process steps as described herein.", "[0085] At a flow point 210 , a prospective borrower desires to obtain a home mortgage loan or similar loan.", "[0086] At a step 221 , the borrower transmits prospective loan information regarding a prospective loan application to a mortgage broker, loan broker, or similar agent.", "In a preferred embodiment, the prospective loan information can be transmitted using an industry standard form for prospective loan information, such as a Form 1003 or Form 1008 .", "The prospective loan information can also be transmitted using a computer file prepared using an existing loan documentation or origination software package.", "[0087] At a step 222 , the broker at the broker station 120 logs in to the transaction server 110 and verifies that the broker station 120 is authorized to access the system 100 .", "In this step, the transaction server 110 transmits any access control data or other data needed to initialize the broker station 120 so as to customize it for access by that individual broker, loan processor, or broker manager.", "[0088] The broker can perform one of a set of functions using the broker station 120 , including the following: managing loan profiles, including—creating a loan profile and adding it to the 24 .", "trading system database 111 ;", "reviewing a loan profile already in the trading system database 111 ;", "altering or otherwise updating a loan profile already in the trading system database 111 managing loan portfolios, including—searching pending loan profiles for those with or without bids, or for those with accepted bids managing bids on loans, including—viewing bids on loan profiles, accepting bids, viewing accepted bids viewing market information, including—viewing real time market data, viewing other mortgage news feeds or other news feeds prequalifying borrowers, including—viewing interest rates available on the system 100 , such as the average interest rate, high interest rate, low interest rate, or median interest rate associated with selected loan profile information;", "viewing aggregate interest rates for the entire system 100 ;", "viewing lender activity in terms of number of lenders who have purchased selected types of loans managing lender selection, including—deselecting particular lenders so that those lenders do not see loan profiles from this broker station 120 ;", "reselecting particular lenders communicating with other users of the system 100 , including—electronic mail messages;", "paging password management, including password changes [0097] In a preferred embodiment, the system 100 allows hierarchical management of loans from the perspective of the loan originator.", "A loan processor is allowed to perform these functions on behalf of one or more selected brokers, but is not allowed to post a loan on the loan processor's own behalf.", "Brokers can delegate authority to loan processors to post loans, and can exclude or include authority to accept bids with that delegation of authority.", "A selected broker manager is allowed to perform these functions as well as to post loans on the manager's own behalf.", "Authorization as a broker, loan processor, or manager is performed in the step 222 during login.", "[0098] At a step 223 , the broker at the broker station 120 interactively enters data for the loan profile, optionally periodically or intermittently save that data, optionally edits that data, optionally validates that data for reasonable values at the broker station 120 , and when complete, prepares to transmit the completed loan profile to the transaction server 110 .", "[0099] At a step 224 , the broker at the broker station 120 optionally reviews financial market information and mortgage market information relevant to the loan profile.", "This allows the broker to set competitive asking prices for loan profiles.", "[0100] At a step 225 , the broker at the broker station 120 sets a selected asking price for the loan profile.", "[0101] At a step 226 , the broker station 120 transmits a loan profile to the transaction server 110 .", "The loan profile includes the prospective loan information, but the transaction server 110 does not identify the borrower or the broker to prospective lenders.", "[0102] At a step 227 , the transaction server 110 validates the information provided for each loan profile, such as determining whether there is in fact a property at the indicated property location and whether there is in fact a property of the indicated property type at the indicated property location.", "If the transaction server 110 determines that the information provided for the loan profile is not valid (to more than a trivial extent), the transaction server 110 responds to the broker station 120 by requesting correction.", "[0103] As part of the step 227 , the transaction server 110 or the broker station 120 can transform certain data entry values so as to make it convenient for the broker to enter data.", "For example, for loan amount, the transaction server 110 or the broker station 120 can accept the value “300K”", "and transform that to the value “300,000.”", "[0104] Also as part of the step 227 , the transaction server 110 provides for detecting substantially identical loan profiles originated by the same broker station 120 , so as to prevent multiple applications for the same borrower for the same property;", "this practice is sometimes known as “double apping.”", "[0105] At a step 228 , the transaction server 110 computes any computed information for the loan profile (including determining whether the loan profile is CRA eligible) and stores the loan profile in the trading system database 111 .", "[0106] At a step 229 , the transaction server 110 computes aggregate tags for the loan profile so as to respond to specialized lender queries, such as whether the loan profile is for a “prime”", "loan or a “subprime”", "loan or whether the loan profile is CRA eligible), and stores that information in the loan profile in the trading system database 111 .", "[0107] At a flow point 230 , a prospective lender desires to bid on one or more loan applications.", "[0108] At a step 241 , the lender at the lender station 130 logs in to the transaction server 110 and verifies that the lender station 130 is authorized to access the system 100 .", "[0109] In a preferred embodiment, selected lenders are allowed to access selected categories of loan profiles depending on the nature of their membership or privileges granted to them when signing up for using the system 100 .", "For example, selected portions of the lender's ability to query the trading system database 111 can depend on the level of service the lender requested when signing up for the system 100 .", "As part of the step 241 , this information is transmitted by the transaction server 110 to the lender station 130 upon verification of the lender station 130 .", "[0110] The lender can perform one of a set of functions using the lender station 130 , including the following: managing loan profile searches, including—defining loan profile searches, storing loan profile searches for later use or reuse, directing the transaction server 110 to perform a loan profile search Loan profile searches can specify that the loan profile can be considered for community investment purposes or is CRA qualified.", "Loan profile searches can also be specified to be “active,” in which the transaction server 110 is directed to periodically perform the loan profile search on updated contents of the trading system database 111 , and to notify the lender station 130 of revised results of the active loan profile search.", "managing search results, including—viewing results of a loan profile search managing bids on loans, including—placing bids on loan profiles, receiving notification of accepted bids The transaction server 110 provides limited information to this particular lender station 130 on bids placed by other lender stations 130 .", "In the case that this particular lender station 130 had the winning bid, the next best bid is provided for display;", "in the case that this particular lender station 130 had its bid rejected, the winning bid is provided for display.", "managing loan portfolios, including—searching loan profiles for accepted bids;", "searching loan profiles for selected status of loan processing;", "viewing particular loan profiles for bid or processing status viewing market information, including—viewing real time market data, viewing other mortgage news feeds or other news feeds managing broker selection, including—deselecting particular brokers so that loan profiles from those brokers are not found by loan profile searches from this lender station 130 ;", "reselecting particular brokers;", "viewing due diligence information on particular brokers communicating with other users of the system 100 , including—electronic mail messages;", "paging password management, including—password changes [0122] At a step 242 , the lender at the lender station 130 determines a query profile for querying the database, depending on the loan programs available to the lender at that time.", "In a preferred embodiment, the lender station 130 optionally stores the query profiles, so that the lender can optionally use or modify a query profile for reuse.", "[0123] At a step 243 , the lender at the lender station 130 transmits a database s query to the transaction server, requesting loan profiles regarding prospective loans which might be of interest to the lender.", "As part of the query, the lender can choose to retrieve only those loans on which the lender has not already bid, or to retrieve all such a loans regardless of their bid status.", "[0124] Although the lender is not informed of the identity of the borrower, the lender can query for searchable database elements relating to the borrower.", "For example, the lender can search on criteria such as the following: loan category (FHLMC, FNMA, Conduit, VA, FHA, Other);", "loan type (adjustable or fixed interest rate);", "amortization time;", "loan purpose (new purchase, improvement);", "occupancy status calculated credit information for the loan, such as a LTV (loan to value) ratio, a qualifying credit score, front and back ratios, loan lock period, a total loan amount, whether the loan is “conforming”", "particular qualifying credit information regarding the borrower, such as gross family income, other outstanding debts, or credit history reports particular credit information regarding the property, such as its nature (raw land, condominium, detached single family home, apartment less than four units, income property), its location (census tract, zip code, city, county, state), and whether it qualifies for CRA (Community Reinvestment Act) credit for the lender particular credit information regarding the broker, such as a history of loan qualification or loan performance for loans originating with that broker [0129] At a step 244 , the transaction server 110 performs a database lookup for the trading system database 111 in response to the database query, and transmits a query response to the lender station 130 .", "The query response identifies loan profiles which match the database query.", "[0130] At a step 245 , the transaction server 110 transmits information regarding is loan profiles matching the query to the lender station 130 .", "In a preferred embodiment, loans already bid upon by the lender are so marked, such as by being displayed in a different color.", "[0131] At a step 246 , the lender at the lender station 130 can view details of the loan profile interactively.", "In a preferred embodiment, the lender's attention is drawn by marking selected loan profiles, such as by being displayed in a different color.", "Selected loan profiles can include those having comments regarding the nature of the property or qualifying qualitative remarks.", "[0132] At a step 247 , the lender at the lender station 130 optionally reviews the lender's portfolio of those loans with accepted or rejected bids and those loans waiting for responses from brokers at broker stations 120 .", "The lender at the lender station 130 optionally reviews the lender's bids declined by brokers at broker stations 120 against winning bids, and optionally reviews the lender's winning bids against others'", "bids declined by brokers at broker stations 120 .", "The lender at the lender station 130 optionally reviews market performance, including activity in the system 100 .", "[0133] At a step 248 , the lender at the lender station 130 selects a loan profile for bid and optionally requests details of that selected loan profile;", "in response, the transaction server 110 transmits details about the loan profiles to the lender station 130 .", "[0134] At a step 249 , the lender at the lender station 130 transmits a bid on one of the loan profiles.", "The transaction server 110 enters the bid in the loan profile, indicating that the lender has bid on the loan profile, but does not identify the lender to prospective borrowers or brokers.", "[0135] The bid can have an associated expiration time, after which the transaction server 110 will mark the bid withdrawn (or delete it), so that it can no longer be accepted.", "[0136] In a preferred embodiment, the lender at the lender station 130 can post a single common bid for multiple loan profiles.", "[0137] At a step 250 , the transaction server 110 transmits a bid notification to each broker station 120 associated with a loan profile which has received a bid.", "The bid notification can include one or more of the following: (a) a bid alert on a display at the broker station 120 , (b) a pager notification to the broker;", "(c) an electronic mail message to the broker station 120 .", "[0138] At a flow point 260 , a prospective borrower desires to accept a bid on a loan application.", "[0139] At a step 271 , the broker at the broker station 120 logs in to the transaction server 110 and verifies that the broker station 120 is authorized to access the system 100 and is authorized to accept bids for that broker.", "[0140] At a step 272 , the broker at the broker station 120 optionally reviews the broker's portfolio of those loans with accepted bids, those loans with pending unaccepted bids, and those loans waiting for bids from lenders at lender stations 130 .", "The broker at the lender station 130 optionally reviews market performance, including activity in the system 100 .", "[0141] At a step 273 , the broker at the broker station 120 selects a loan profile with pending unaccepted bids and optionally requests details of that selected loan profile;", "in response, the transaction server 110 transmits details about the loan profiles to the broker station 120 .", "The broker at the broker station 120 selects one or more pending bids for that loan profile and optionally requests details about those bids;", "in response, the transaction server 110 transmits details about the pending bids to the broker station 120 .", "[0142] At a step 274 , the broker station 120 transmits an acceptance, for a particular bid for a particular loan profile, to the transaction server 110 .", "The transaction server 110 marks that bid at the loan profile as having been accepted, and marks all other bids at the loan profile as having been rejected.", "[0143] At a step 275 , the transaction server 110 notifies the winning bidder lender of the bid acceptance.", "[0144] At a step 276 , the transaction server 110 transmits complete prospective loan information to the lender at the lender station 130 and complete lender information to the broker at the broker station 120 , thus informing the borrower of the identity of the lender and informing the lender of the identity of the borrower.", "[0145] Although the lender at the lender station 130 is not informed of the identity of the broker associated with the loan profile until the bid is accepted, the lender at the lender station 130 can select broker stations 120 for identification as being undesirable, so that loan profiles from those broker stations 120 are not transmitted in the query response.", "Similarly, although the broker at the broker station 120 is not informed of the identity of the lender associated with the bid, the broker at the broker station 120 can select lender stations 130 for identification as being undesirable, so that bids from those lender stations 130 are not displayed in the loan profile (and the broker station 120 is not notified of receipt of bids from those lender stations 130 ).", "[0146] At a step 277 , the broker transmits, either on paper or by EDI (electronic data interchange), a complete loan application package in a format acceptable to the particular lender.", "After verification of the prospective loan information or other formalities, the lender completes the loan.", "[0147] The broker at the broker station 120 can also prequalify prospective borrowers or a prospective loan profile so as to determine feasibility for a particular loan or a particular loan amount.", "[0148] At a flow point 280 , a broker desires to prequalify a prospective borrower.", "[0149] At a step 291 , the broker at the broker station 120 logs in to the transaction server 110 and verifies that the broker station 120 is authorized to access the system 100 .", "[0150] At a step 292 , the transaction server 110 transmits to the broker station 120 , and the broker station 120 initializes, search criteria for prequalification with a set of loan products available from lenders at lender stations 130 or otherwise tradeable on the system 100 .", "[0151] At a step 293 , the broker at the broker station 120 enters preliminary information regarding the prospective borrower, such as—expected credit score, and expected front ratio, back ratio, and LTV ratio.", "The broker at the broker station 120 can enter information regarding points or rates, and obtain current and past corresponding points or rates;", "for example, the broker at the broker station 120 can enter a selected interest rate and obtain the average, high, and low values for points corresponding to that interest rate for completed loan transactions on the system 100 .", "The broker at the broker station 120 can also determine statistics regarding how many lenders have made loans of those types.", "[0152] At a step 294 , the broker at the broker station 120 can inform the prospective borrower about whether or not it is feasible to obtain competitive rates in those contemplated ranges.", "[0153] The transaction server 110 records information regarding pending loan profiles and completed loans for later monitoring and reporting by the administrative client 150 .", "In a preferred embodiment, this information includes at least the following: an audit trail of all actions taken with regard to each particular loan profile, including all transaction data associated with the loan profile for future verification.", "a record of loan performance for loan profiles which have been processed using the system 100 , including a database of loan performance searchable by various criteria [0156] In a preferred embodiment, the borrower and the lender are each charged a fee for the service provided by the transaction server.", "The fee is paid out of escrow funds by a selected escrow company when the loan and an associated purchase of the property are completed.", "The amount of the fee can be fixed or can be varied in response to the prospective loan information, such as the amount of the loan, and in a preferred embodiment is varied in response to CRA qualification for the loan.", "Alternative Embodiments [0157] Although preferred embodiments are disclosed herein, many variations are possible which remain within the concept, scope, and spirit of the invention, and these variations would become clear to those skilled in the art after perusal of this application." ]
FIELD OF THE INVENTION This invention relates to an amplitude modulation detector, and more particularly, to an amplitude modulation detector whose D.C. output component is constant. BACKGROUND OF THE INVENTION It is desirable for an amplitude modulation detector to produce an output whose D.C. voltage component is always constant. This simplifies the design of the audio frequency amplifier (AF amplifier), and also eliminates noise arising at the time of switching frequency bands or switching to or from other sources. Such sources can be, for instance, a frequency modulation detector or tape player combined with the amplitude modulation detector in a set. The noise is caused by a sudden change of the D.C. voltage component of the input signal to the AF amplifier. Conventional amplitude modulation (AM) radio receivers have needed AF amplifiers having wide level response to the input signal from the amplitude modulation detectors. Moreover, multiband type conventional AM receivers or combination sets with an AM receiver section and other signal source section, such as a tape recorder, have used decoupling capacitors connected before the AF amplifiers. However, the decoupling capacitors are difficult to fabricate when using integrated circuits (IC circuits). SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide an AM detector producing an output whose D.C. component is constant. Another object of the present invention is to provide an AM detector which can be directly connected to an amplifier section without a decoupling capacitor. According to the present invention, the AM detector is provided with (a) AM detection means responsive to first and second input signals for maintaining a constant D.C. level output signal, the first signal being the AM signal, and (b) feedback means connected to the output of the detection means for comparing the D.C. output level of the detection means with a reference signal level to produce the second signal. Additional objects and advantages of the present invention will become apparent to persons skilled in the art from a study of the following description of the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an amplitude modulation detector of the prior art; FIG. 2 is a graph showing the output signals of the amplitude modulation detector shown in FIG. 1; FIG. 3 shows a block diagram of an amplitude modulation detector according to the present invention; FIG. 4 is a graph showing input and output signals of the amplitude modulation detector shown in FIG. 3; FIG. 5 shows a detailed circuit diagram of the amplitude modulation detector shown in FIG. 3; and FIG. 6 shows a block diagram of another embodiment according to the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention will be described in detail with reference to the accompanying drawings FIG. 1 to FIG. 6. Throughout the drawings, like reference numerals will be used to designate like or equivalent elements. The prior art to which this invention is an improvement includes an input signal source 10 such as an IF amplifier, a coupling transformer 12 and a detection diode 14. An AM signal S in is applied from input signal source 10 to detection diode 14 through coupling transformer 12. The AM signal is composed of an intermediate frequency signal (IF signal) modulated by an audio frequency signal (AF signal). The AM signal is detected by detection diode 14 so that a rectified signal of the AM signal appears on output terminal 16 connected to detection diode 14. An IF frequency component included in the rectified signal is bypassed through capacitor 18 connected between output terminal 16 and reference potential terminal 20 so that an output on output terminal 16 is a signal composed of the AF signal component and a D.C. component. In FIG. 2, the output signal is typically shown by the waveform S L representing a low level condition or by the waveform S H representing a high level condition. The level condition of the output signal varies in accordance with the amplitude level of the IF signal. Low level output signal S L is composed of the AF signal denoted by S A and a D.C. component by V L where S L =S A +V L . On the other hand, high level output signal S H is composed of AF signal S A and another D.C. component denoted by V H where S H =S A +V H . The AM detector shown in FIG. 1 has several limitations as described below. First, detection diode 14 is required to have good linearity of its forward input voltage-output current characteristics. Otherwise the output signal will be distorted when the AM signal is relatively large. Secondly, an AF amplifier which follows the AM detector must have a large input capacity, or otherwise be connected to the AM detector through a decoupling capacitor which is difficult using IC circuitry. Referring now to FIG. 3, there is shown a block diagram of an AM detector of one embodiment of the present invention, which comprises input signal source 10, detection diode 14 and D.C. voltage comparator 22. The input signal source, which can be for example an IF amplifier 10, is connected to the anode of detection diode 14. The cathode of detection diode 14 is not only connected to output terminal 16, but also to one input of a D.C. voltage comparator, such as a D.C. amplifier 22. A second input of D.C. amplifier 22 is connected to reference voltage source 24. The output of D.C. amplifier 22 is connected through load impedance 28 to amplifier 10 and detection diode 14. The AM signal with IF frequency is applied from IF amplifier 10 to detection diode 14 so that the rectified signal of the AM signal appears on output terminal 16. An IF frequency component in the rectified signal is bypassed through capacitor 18 connected between the cathode of detection diode 14 and reference potential terminal 20. The output signal on output terminal 16 is composed of AF signal component S A and D.C. component V, as shown in FIG. 4. D.C. component V is applied to D.C. amplifier 22 and compared with reference voltage V R of reference voltage source 24. D.C. amplifier 22 gives a D.C. output V O which depends on the difference voltage between reference voltage V R and D.C. component V of the rectified signal. Any component of AF frequency leaking to the output of D.C. amplifier 22 is bypassed through capacitor 30 connected between the output of D.C. amplifier 22 and reference potential terminal 20. Accordingly, the combined AM signal and D.C. output V O are applied to detection diode 14. Therefore, D.C. component V is a voltage composed of the rectified voltage of the AM signal itself and D.C. output V O . When the AM signal level varies, D.C. component V will vary. D.C. output V O of D.C. amplifier 22 will vary with changes in the D.C. component V but oppositely to it. Thus, when the level of the AM signal increases, the D.C. voltage level at node 26 is lowered because D.C. output V O decreases in direct relation with the increase of D.C. component V. Accordingly, D.C. output V O operates to minimize the change of D.C. component V. As a result, D.C. component V is held at the value of reference voltage V R in spite of level changes of the AM signal. Therefore, the output signal of detection diode 14 always is a constant D.C. component V held sustantially equal to the reference voltage V R . D.C. output V O of D.C. amplifier 22 is applied to the automatic gain control (AGC) terminal 32 of IF amplifier 10 to control the level of the IF signal in correspondence with the change of D.C. output V O . The suppression rate of change K of the D.C. component is a function of loop gain G of the negative feedback (NF) loop comprised of detection diode 14 and D.C. amplifier 22, and represented as follows: K=1/G The loop gain G is a function of transfer conductance gm of D.C. amplifier 22, and is represented as follows: ##EQU1## where Zo is an output impedance of IF amplifier 10, and Zi is the input impedance of detection diode 14. Therefore, the suppression rate K is given by the following equation: ##EQU2## It is best to keep the suppression rate K as small as possible, but an excessively small rate K causes the loop to oscillate badly. Therefore the preferred value for rate K is in the range of 1/10 to 1/100, or 20 dB to 40 dB. Referring now to FIG. 5, there is shown a detailed circuit diagram of a preferred embodiment of the AM detector. IF amplifier 10 is constituted by two differential amplifiers 40 and 42. First differential amplifier 40 includes three NPN transistors 44, 46 and 48, transistors 44 and 46 being coupled at their emitters to one another and transistor 48 in turn being coupled at its collector to the emitters of transistors 44 and 46. Transistors 44 and 46 are connected at their bases to input terminals 50 and 52 adapted for connection to an IF convertor (not shown), and at their collectors to positive voltage source terminal 54 via resistance loads 56 and 58 respectively. Transistor 48 is connected at its emitter to reference potential terminal 20 via resistor 60 and at its base to a voltage supply circuit 62. The voltage supply circuit 62, which supplies a constant voltage, includes diode 64 which connects at its anode to positive voltage source terminal 54 through resistor 66 and at its cathode to reference potential terminal 20 through resistor 68. Second differential amplifier 42 also includes three NPN transistors 70, 72 and 74, transistors 70 and 72 being coupled at their emitters to one another and transistor 74 being coupled at its collector to the emitters of transistors 70 and 72. Transistors 70 and 72 are connected at their bases to first differential amplifier 40 at the respective collectors of transistors 44 and 46, and at their collectors to positive voltage source terminal 54. Transistor 70 is directly coupled to source 54 and transistor 72 is connected through current mirror circuit 78. Transistor 74 is connected at its emitter to reference potential terminal 20 via resistor 76 and at its base to voltage supply circuit 62. Current mirror circuit 78 includes diode 80 connected in forward bias relationship between the collector of transistor 72 and positive voltage source terminal 54. PNP transistor 82 is connected having its emitter-base path in parallel with diode 80. The collector of transistor 82 forms an output terminal of IF amplifier 10. Detection diode 14 is connected to IF amplifier 10. Detection diode 14 is connected at its cathode to the collector of transistor 82 and at its anode to output terminal 16 through buffer amplifier 84. Buffer amplifier 84 includes NPN transistors 86, 88 and 90, PNP transistor 92 and diode 94. Two NPN transistors 86 and 88 are connected at their bases respectively to detection diode 14 and output terminal 16 and connected to each other in a differential amplifier arrangement. Another NPN transistor 90 is connected at its collector to the emitters of transistors 86 and 88, at its emitter to reference potential terminal 20 through resistor 96, and at its base to voltage supply circuit 62. Diode 94 and PNP transistor 92 are connected to each other in a current mirror circuit. The base of transistor 86 is connected to reference potential terminal 20 through capacitor 98. The base of transistor 88 is coupled to its collector and connected to output terminal 16 via low pass filter 100. Output terminal 16 is connected to the base of NPN transistor 22 which operates as a D.C. voltage comparator. Transistor 22 is connected at its emitter to reference potential terminal 20 through resistor 24 as a reference voltage source. The collector of transistor 22 is connected to node 26 between IF amplifier 10 and detection diode 14. LC tank circuit 28, which is the load for the second differential amplifier 42 of IF amplifier 10, is connected to reference potential terminal 20 through capacitor 30. The collector of transistor 22 is further connected to the base of NPN transistor 32 as an AGC circuit for IF amplifier 10. Transistor 32 is connected at its emitter to the emitter of transistor 60 in first differential amplifier 40. The operation of the AM detector shown in FIG. 5 is described as follows. An IF signal, converted from an RF signal, is applied across input terminals 50 and 52, and amplified by first and second differential amplifiers 40 and 42. Then, the amplified IF signal is applied to detection diode 14 and rectified by detection diode 14. An audio frequency (AF) signal component as an envelope of negative half cycles of the IF signal appears on the anode of detection diode 14, but the IF frequency component of rectified IF signal is filtered by capacitor 98. The AF signal is brought to output terminal 16 after being amplified by buffer amplifier 84 and any IF frequency component is filtered by low pass filter 100. An output signal on output terminal 16 is applied to and processed by the D.C. voltage comparator, transistor 22. That is, the base of transistor 22 is connected to output terminal 16 the output signal. The output signal is compared with its emitter potential generated by a voltage drop across resistor 24. An amplified AF signal component on the collector of transistor 22 is filtered by capacitor 30. Therefore, a collector potential, referred to the difference between the emitter potential and the base potential, is applied to connection node 26 between IF amplifier 10 and detection diode 14 through LC tank circuit 28. As a result, the D.C. voltage component of the output signal on output terminal 16 is controlled at a constant voltage level by the effect of negative feedback through transistor 22. The constant D.C. voltage V C is obtained by the following equation: ##EQU3## where I 22 is a D.C. current through transistor 22, R 24 is a resistance of resistor 24 and V BE22 is a base-emitter voltage of transistor 22. D.C. current I 22 is equal to the D.C. current through diode 80 or transistor 72 of second differential amplifier 42. D.C. currents through transistors 70 and 72 are equal to each other and both are supplied from transistor 74. Therefore, D.C. current I 22 is expressed as follows, in terms of D.C. current I 74 through transistor 74, I.sub.22 =I.sub.74 /2 Accordingly, the equation (1) is rewritten as follows, ##EQU4## D.C. current I 74 may be set constant since transistor 74 operates as a constant current source circuit. Base-emitter voltage V BE22 is substantially constant; for silicon transistors it is about 0.7 volts. Therefore, D.C. voltage V C of the output signal can be set constant in spite of amplitude level fluctuations of the IF signal from IF amplifier 10. The collector potential of transistor 22, however, varies in accordance with the amplitude level fluctuations of the IF signal so that the varying collector potential of transistor 22 may be applied in feedback relationship to AGC transistor 32. Referring now to FIG. 6, there is shown a block diagram of a modification of the AM detector. This embodiment differs from that of FIG. 3 in that an output of D.C. voltage comparator 22 is directly applied to connection node 26.
The amplitude modulation detection device, which is provided with an AM (amplitude modulation) responsive to first and second input signals for maintaining a constant D.C. level output signal, the first signal being the AM signal, and the second signal produced by feedback loop which includes a D.C. voltage comparator connected to the detector for comparing the D.C. output level of the detector with a reference signal level.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "FIELD OF THE INVENTION This invention relates to an amplitude modulation detector, and more particularly, to an amplitude modulation detector whose D.C. output component is constant.", "BACKGROUND OF THE INVENTION It is desirable for an amplitude modulation detector to produce an output whose D.C. voltage component is always constant.", "This simplifies the design of the audio frequency amplifier (AF amplifier), and also eliminates noise arising at the time of switching frequency bands or switching to or from other sources.", "Such sources can be, for instance, a frequency modulation detector or tape player combined with the amplitude modulation detector in a set.", "The noise is caused by a sudden change of the D.C. voltage component of the input signal to the AF amplifier.", "Conventional amplitude modulation (AM) radio receivers have needed AF amplifiers having wide level response to the input signal from the amplitude modulation detectors.", "Moreover, multiband type conventional AM receivers or combination sets with an AM receiver section and other signal source section, such as a tape recorder, have used decoupling capacitors connected before the AF amplifiers.", "However, the decoupling capacitors are difficult to fabricate when using integrated circuits (IC circuits).", "SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide an AM detector producing an output whose D.C. component is constant.", "Another object of the present invention is to provide an AM detector which can be directly connected to an amplifier section without a decoupling capacitor.", "According to the present invention, the AM detector is provided with (a) AM detection means responsive to first and second input signals for maintaining a constant D.C. level output signal, the first signal being the AM signal, and (b) feedback means connected to the output of the detection means for comparing the D.C. output level of the detection means with a reference signal level to produce the second signal.", "Additional objects and advantages of the present invention will become apparent to persons skilled in the art from a study of the following description of the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an amplitude modulation detector of the prior art;", "FIG. 2 is a graph showing the output signals of the amplitude modulation detector shown in FIG. 1;", "FIG. 3 shows a block diagram of an amplitude modulation detector according to the present invention;", "FIG. 4 is a graph showing input and output signals of the amplitude modulation detector shown in FIG. 3;", "FIG. 5 shows a detailed circuit diagram of the amplitude modulation detector shown in FIG. 3;", "and FIG. 6 shows a block diagram of another embodiment according to the present invention.", "DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention will be described in detail with reference to the accompanying drawings FIG. 1 to FIG. 6. Throughout the drawings, like reference numerals will be used to designate like or equivalent elements.", "The prior art to which this invention is an improvement includes an input signal source 10 such as an IF amplifier, a coupling transformer 12 and a detection diode 14.", "An AM signal S in is applied from input signal source 10 to detection diode 14 through coupling transformer 12.", "The AM signal is composed of an intermediate frequency signal (IF signal) modulated by an audio frequency signal (AF signal).", "The AM signal is detected by detection diode 14 so that a rectified signal of the AM signal appears on output terminal 16 connected to detection diode 14.", "An IF frequency component included in the rectified signal is bypassed through capacitor 18 connected between output terminal 16 and reference potential terminal 20 so that an output on output terminal 16 is a signal composed of the AF signal component and a D.C. component.", "In FIG. 2, the output signal is typically shown by the waveform S L representing a low level condition or by the waveform S H representing a high level condition.", "The level condition of the output signal varies in accordance with the amplitude level of the IF signal.", "Low level output signal S L is composed of the AF signal denoted by S A and a D.C. component by V L where S L =S A +V L .", "On the other hand, high level output signal S H is composed of AF signal S A and another D.C. component denoted by V H where S H =S A +V H .", "The AM detector shown in FIG. 1 has several limitations as described below.", "First, detection diode 14 is required to have good linearity of its forward input voltage-output current characteristics.", "Otherwise the output signal will be distorted when the AM signal is relatively large.", "Secondly, an AF amplifier which follows the AM detector must have a large input capacity, or otherwise be connected to the AM detector through a decoupling capacitor which is difficult using IC circuitry.", "Referring now to FIG. 3, there is shown a block diagram of an AM detector of one embodiment of the present invention, which comprises input signal source 10, detection diode 14 and D.C. voltage comparator 22.", "The input signal source, which can be for example an IF amplifier 10, is connected to the anode of detection diode 14.", "The cathode of detection diode 14 is not only connected to output terminal 16, but also to one input of a D.C. voltage comparator, such as a D.C. amplifier 22.", "A second input of D.C. amplifier 22 is connected to reference voltage source 24.", "The output of D.C. amplifier 22 is connected through load impedance 28 to amplifier 10 and detection diode 14.", "The AM signal with IF frequency is applied from IF amplifier 10 to detection diode 14 so that the rectified signal of the AM signal appears on output terminal 16.", "An IF frequency component in the rectified signal is bypassed through capacitor 18 connected between the cathode of detection diode 14 and reference potential terminal 20.", "The output signal on output terminal 16 is composed of AF signal component S A and D.C. component V, as shown in FIG. 4. D.C. component V is applied to D.C. amplifier 22 and compared with reference voltage V R of reference voltage source 24.", "D.C. amplifier 22 gives a D.C. output V O which depends on the difference voltage between reference voltage V R and D.C. component V of the rectified signal.", "Any component of AF frequency leaking to the output of D.C. amplifier 22 is bypassed through capacitor 30 connected between the output of D.C. amplifier 22 and reference potential terminal 20.", "Accordingly, the combined AM signal and D.C. output V O are applied to detection diode 14.", "Therefore, D.C. component V is a voltage composed of the rectified voltage of the AM signal itself and D.C. output V O .", "When the AM signal level varies, D.C. component V will vary.", "D.C. output V O of D.C. amplifier 22 will vary with changes in the D.C. component V but oppositely to it.", "Thus, when the level of the AM signal increases, the D.C. voltage level at node 26 is lowered because D.C. output V O decreases in direct relation with the increase of D.C. component V. Accordingly, D.C. output V O operates to minimize the change of D.C. component V. As a result, D.C. component V is held at the value of reference voltage V R in spite of level changes of the AM signal.", "Therefore, the output signal of detection diode 14 always is a constant D.C. component V held sustantially equal to the reference voltage V R .", "D.C. output V O of D.C. amplifier 22 is applied to the automatic gain control (AGC) terminal 32 of IF amplifier 10 to control the level of the IF signal in correspondence with the change of D.C. output V O .", "The suppression rate of change K of the D.C. component is a function of loop gain G of the negative feedback (NF) loop comprised of detection diode 14 and D.C. amplifier 22, and represented as follows: K=1/G The loop gain G is a function of transfer conductance gm of D.C. amplifier 22, and is represented as follows: ##EQU1## where Zo is an output impedance of IF amplifier 10, and Zi is the input impedance of detection diode 14.", "Therefore, the suppression rate K is given by the following equation: ##EQU2## It is best to keep the suppression rate K as small as possible, but an excessively small rate K causes the loop to oscillate badly.", "Therefore the preferred value for rate K is in the range of 1/10 to 1/100, or 20 dB to 40 dB.", "Referring now to FIG. 5, there is shown a detailed circuit diagram of a preferred embodiment of the AM detector.", "IF amplifier 10 is constituted by two differential amplifiers 40 and 42.", "First differential amplifier 40 includes three NPN transistors 44, 46 and 48, transistors 44 and 46 being coupled at their emitters to one another and transistor 48 in turn being coupled at its collector to the emitters of transistors 44 and 46.", "Transistors 44 and 46 are connected at their bases to input terminals 50 and 52 adapted for connection to an IF convertor (not shown), and at their collectors to positive voltage source terminal 54 via resistance loads 56 and 58 respectively.", "Transistor 48 is connected at its emitter to reference potential terminal 20 via resistor 60 and at its base to a voltage supply circuit 62.", "The voltage supply circuit 62, which supplies a constant voltage, includes diode 64 which connects at its anode to positive voltage source terminal 54 through resistor 66 and at its cathode to reference potential terminal 20 through resistor 68.", "Second differential amplifier 42 also includes three NPN transistors 70, 72 and 74, transistors 70 and 72 being coupled at their emitters to one another and transistor 74 being coupled at its collector to the emitters of transistors 70 and 72.", "Transistors 70 and 72 are connected at their bases to first differential amplifier 40 at the respective collectors of transistors 44 and 46, and at their collectors to positive voltage source terminal 54.", "Transistor 70 is directly coupled to source 54 and transistor 72 is connected through current mirror circuit 78.", "Transistor 74 is connected at its emitter to reference potential terminal 20 via resistor 76 and at its base to voltage supply circuit 62.", "Current mirror circuit 78 includes diode 80 connected in forward bias relationship between the collector of transistor 72 and positive voltage source terminal 54.", "PNP transistor 82 is connected having its emitter-base path in parallel with diode 80.", "The collector of transistor 82 forms an output terminal of IF amplifier 10.", "Detection diode 14 is connected to IF amplifier 10.", "Detection diode 14 is connected at its cathode to the collector of transistor 82 and at its anode to output terminal 16 through buffer amplifier 84.", "Buffer amplifier 84 includes NPN transistors 86, 88 and 90, PNP transistor 92 and diode 94.", "Two NPN transistors 86 and 88 are connected at their bases respectively to detection diode 14 and output terminal 16 and connected to each other in a differential amplifier arrangement.", "Another NPN transistor 90 is connected at its collector to the emitters of transistors 86 and 88, at its emitter to reference potential terminal 20 through resistor 96, and at its base to voltage supply circuit 62.", "Diode 94 and PNP transistor 92 are connected to each other in a current mirror circuit.", "The base of transistor 86 is connected to reference potential terminal 20 through capacitor 98.", "The base of transistor 88 is coupled to its collector and connected to output terminal 16 via low pass filter 100.", "Output terminal 16 is connected to the base of NPN transistor 22 which operates as a D.C. voltage comparator.", "Transistor 22 is connected at its emitter to reference potential terminal 20 through resistor 24 as a reference voltage source.", "The collector of transistor 22 is connected to node 26 between IF amplifier 10 and detection diode 14.", "LC tank circuit 28, which is the load for the second differential amplifier 42 of IF amplifier 10, is connected to reference potential terminal 20 through capacitor 30.", "The collector of transistor 22 is further connected to the base of NPN transistor 32 as an AGC circuit for IF amplifier 10.", "Transistor 32 is connected at its emitter to the emitter of transistor 60 in first differential amplifier 40.", "The operation of the AM detector shown in FIG. 5 is described as follows.", "An IF signal, converted from an RF signal, is applied across input terminals 50 and 52, and amplified by first and second differential amplifiers 40 and 42.", "Then, the amplified IF signal is applied to detection diode 14 and rectified by detection diode 14.", "An audio frequency (AF) signal component as an envelope of negative half cycles of the IF signal appears on the anode of detection diode 14, but the IF frequency component of rectified IF signal is filtered by capacitor 98.", "The AF signal is brought to output terminal 16 after being amplified by buffer amplifier 84 and any IF frequency component is filtered by low pass filter 100.", "An output signal on output terminal 16 is applied to and processed by the D.C. voltage comparator, transistor 22.", "That is, the base of transistor 22 is connected to output terminal 16 the output signal.", "The output signal is compared with its emitter potential generated by a voltage drop across resistor 24.", "An amplified AF signal component on the collector of transistor 22 is filtered by capacitor 30.", "Therefore, a collector potential, referred to the difference between the emitter potential and the base potential, is applied to connection node 26 between IF amplifier 10 and detection diode 14 through LC tank circuit 28.", "As a result, the D.C. voltage component of the output signal on output terminal 16 is controlled at a constant voltage level by the effect of negative feedback through transistor 22.", "The constant D.C. voltage V C is obtained by the following equation: ##EQU3## where I 22 is a D.C. current through transistor 22, R 24 is a resistance of resistor 24 and V BE22 is a base-emitter voltage of transistor 22.", "D.C. current I 22 is equal to the D.C. current through diode 80 or transistor 72 of second differential amplifier 42.", "D.C. currents through transistors 70 and 72 are equal to each other and both are supplied from transistor 74.", "Therefore, D.C. current I 22 is expressed as follows, in terms of D.C. current I 74 through transistor 74, I.sub[.", "].22 =I.", "sub[.", "].74 /2 Accordingly, the equation (1) is rewritten as follows, ##EQU4## D.C. current I 74 may be set constant since transistor 74 operates as a constant current source circuit.", "Base-emitter voltage V BE22 is substantially constant;", "for silicon transistors it is about 0.7 volts.", "Therefore, D.C. voltage V C of the output signal can be set constant in spite of amplitude level fluctuations of the IF signal from IF amplifier 10.", "The collector potential of transistor 22, however, varies in accordance with the amplitude level fluctuations of the IF signal so that the varying collector potential of transistor 22 may be applied in feedback relationship to AGC transistor 32.", "Referring now to FIG. 6, there is shown a block diagram of a modification of the AM detector.", "This embodiment differs from that of FIG. 3 in that an output of D.C. voltage comparator 22 is directly applied to connection node 26." ]
[0001] This application claims the benefit of U.S. Provisional Patent Application 61/847,093, filed on 17 Jul. 2013, and U.S. Provisional Patent Application 61/865,625, filed on 14 Aug. 2013, the specifications of which are hereby incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] Embodiments of the invention generally relate to an implantable heart therapy device having a therapy control unit that includes a tachycardia identification unit. The heart therapy device also includes a right-ventricular stimulation unit and a left-ventricular stimulation unit, wherein both the right-ventricular stimulation unit and the left-ventricular stimulation unit are connected to the therapy control unit. The therapy control unit triggers antitachycardia stimulation (ATP). [0004] 2. Description of the Related Art [0005] European Patent 1 857 140 to Doerr et al., entitled “Heart Stimulator”, discloses a heart therapy device having a stimulation unit that is connected or can be connected to a stimulation electrode in order to stimulate a ventricle of a heart. The stimulation unit, of Doerr et al., may generate both stimulation pulses and defibrillation shocks, and may include at least one high-voltage capacitor, in which the electrical energy necessary for a defibrillation shock is stored. [0006] Generally, heart therapy devices may include a detector that processes physiological signals received from the heart and, on the basis thereof, detects the presence of an acute ventricular tachycardia or fibrillation. Typically, heart therapy devices may also include a control unit connected to the detector and the stimulation unit, wherein the control unit is responsive to an output signal of the detector to control the stimulation unit to deliver a sequence of stimulation pulses or to deliver a defibrillation shock forming an antitachycardia therapy. The heart therapy device of Doerr et al. enables therapy delivery to a right ventricle of the heart. [0007] Generally, heart therapy devices may be referred to as implantable cardioverter-defibrillators (ICD). Typically, heart therapy devices referred to herein are primarily implantable heart therapy devices that are able to treat tachycardia of the heart. [0008] Generally, the term “tachycardias” includes both tachycardias represented by a stable heartbeat with pathologically high frequency, and also fibrillations. Therapies delivered by a heart stimulator, generally, include an antitachycardia stimulation or a defibrillation shock. [0009] A defibrillation shock is typically an electrical pulse delivered to the heart and has sufficiently high voltage and energy to fully excite a heart chamber affected by fibrillation to therefore make the heart chamber refractory. Therefore, re-entrant excitation pulses, typical for fibrillations, are interrupted. In the case of tachycardia wherein a ventricle is affected, the tachycardia is often also referred to as ventricular tachycardia and is abbreviated by VT (in contrast to ventricular fibrillation VF). Generally, successful therapy is often possible using antitachycardia stimulation (antitachyarrhythmia pacing: ATP). Generally, with antitachycardia stimulation, the heart stimulator outputs a sequence of stimulation pulses, of which the energy is significantly lower than the energy of a defibrillation shock and which are not painful. Typically, with antitachycardia stimulation, such stimulation pulses of comparatively low energy are delivered with a frequency that is greater than the frequency of the determined tachycardia. Generally, tachycardia may be stopped in this way without a patient suffering from pain or without the energy demand being particularly high. [0010] Typical therapy devices generally deliver stimulation pulses to one or both ventricles of a heart, to the left ventricle (LV) and/or to the right ventricle (RV). Such therapy devices are generally referred to as biventricular therapy devices. [0011] Generally, previous ICD systems available on the market may operate exclusively with a right-ventricular VT/VF identification channel for the tachycardia identification and for the corresponding therapy selection. Typically, the stimulation location of the ATP may be programmed statically (RV, LV, BiV). [0012] Generally, ICD systems may also provide, in the VF zone, an ATP therapy attempt, which is delivered immediately before or with the onset of charging, but only when the right-ventricular rhythm meets a frequency and/or stability criterion at the same time; such as an ATP one shot. [0013] Typically, purely right-ventricular sensing used with current ICD systems may have the disadvantage that, in the event of dissimilar ventricular tachyarrhythmia, an incorrect therapy may be selected. If, for example, the rhythm in the right ventricle is already in a VF zone and is unstable, but the left ventricle is still stable, generally, the selection of a defibrillation shock is preferred over an ATP, although clinical observations show that an ATP delivery, for example in the left ventricle, may have a higher therapy success rate. [0014] Generally, a further disadvantage of current systems includes the exclusive use of right-ventricular sensing for synchronization of a left-ventricular ATP. Typically, the exclusive use of right-ventricular sensing may be the reason why no clinical studies are known that demonstrate an advantage of left-ventricular ATP. [0015] Generally, one-time ATP attempts in the VF zone do not take into account the left-ventricular rhythm and also do not take into account potential rhythm regularization during the charging time, and therefore potentially effective ATP attempts are not delivered. BRIEF SUMMARY OF THE INVENTION [0016] At least one embodiment of the invention includes an implantable therapy device that enables high therapy efficiency of antitachycardia stimulation (ATP). [0017] One or more embodiments of the invention include an implantable heart therapy device having a therapy control unit, which includes a tachycardia identification unit connected, at least indirectly, to at least one right-ventricular sensing electrode and at least one left-ventricular sensing electrode. In at least one embodiment of the invention, the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode may feed at least one signal from the heart's right ventricle and at least one signal from the heart's left ventricle, respectively, to the tachycardia identification unit. In one or more embodiments, the signals represent a course over time of electrical potentials in the heart. During operation, in one or more embodiments, the signals representing a course over time of electric potentials in the heart or signals derived therefrom are fed to the tachycardia identification unit. By way of at least one embodiment, the tachycardia identification unit may evaluate the signals fed thereto and/or the course over time thereof, and may generate a tachyarrhythmia signal if the (fed) signal meets predefined criteria. In at least one embodiment, the tachycardia identification unit may simultaneously evaluate the heart rate at the at least one right-ventricular sensing electrode and at the at least one left-ventricular sensing electrode to identify ventricular tachycardia. [0018] According to one or more embodiments, the implantable heart therapy device may include a right-ventricular stimulation unit and a left-ventricular stimulation unit connected to the therapy control unit. The right-ventricular stimulation unit and the left-ventricular stimulation unit, in at least one embodiment, may, in combination with the therapy control unit, generate stimulation pulses for one or more of a right-ventricular and a left-ventricular antitachycardia stimulation therapy (ATP). In at least one embodiment, the right-ventricular stimulation unit and the left-ventricular stimulation unit may deliver the stimulation pulses via the at least one right-ventricular stimulation electrode or the left-ventricular stimulation electrode connected thereto, respectively. [0019] In one or more embodiments, the tachycardia identification unit may detect and determine a dissimilar tachycardia that is greater than the heart rates sensed via the right-ventricular sensing electrode and via the left-ventricular sensing electrode. In at least one embodiment, the therapy control unit may control a delivery of the stimulation pulses for one or more of the right-ventricular and the left ventricular antitachycardia stimulation via the at least one right-ventricular or the at least one left-ventricular stimulation electrode, such that the stimulation pulses for antitachycardia stimulation are delivered via the stimulation electrode which is assigned to the same ventricle as the at least one right-ventricular sensing electrode or the at least one left-ventricular sensing electrode via which, in the event of the dissimilar tachycardia, at least one signal representing the lower heart rate is established or detected. In at least one embodiment, the control of the delivery of the stimulation pulses may be based on a frequency criterion for a selection of a therapy channel, wherein the therapy channel denotes a stimulation unit, of one or more of the right-ventricular stimulation unit and the left-ventricular stimulation unit, assigned to a respective ventricle. [0020] At least one embodiment of the invention uses biventricular sensing to optimize the therapy efficiency of the antitachycardia stimulation (ATP) to automatically determine the (ATP) stimulation location (RV, LV) in patients with dissimilar ventricular tachycardias. The heart therapy device, according to one or more embodiments of the invention, enable a considerable increase in the efficiency of the antitachycardia stimulation and thus simultaneously reduce the need for defibrillation therapies, for example shock reduction. [0021] The heart therapy device, according to at least one embodiment of the invention, may include an implantable defibrillator connected to at least one right-ventricular electrode and to at least one left-ventricular electrode that sense and stimulate the heart. In one or more embodiments, each of the at least one right-ventricular electrode and the at least one left-ventricular electrode are connected to the tachycardia identification unit. In at least one embodiment, the tachycardia identification unit may identify ventricular tachycardias, and may evaluate the heart rate at the at least one right-ventricular and at the at least one left-ventricular electrode simultaneously. The heart therapy device, such as the implantable defibrillator, in at least one embodiment, includes a right-ventricular stimulation unit that delivers antitachycardia stimulation to the right-ventricular electrode, a left-ventricular stimulation unit that delivers antitachycardia stimulation to the left-ventricular electrode. In one or more embodiments, the heart therapy device may include an evaluation control unit that may be part of the therapy control unit wherein the evaluation control unit may determine the stimulation location for the antitachycardia stimulation on the slower ventricle side when dissimilar tachycardia is present. [0022] By one or more embodiments of the invention, the heart therapy device enables the therapy efficiency of the ATP to rise significantly and thus reduces the number of necessary shock deliveries. At least one embodiment of the invention includes a 3-chamber ICD, wherein a considerable proportion of episodes with dissimilar ventricular tachycardias may exist, and the progressions of a rhythm of quick tachycardias may also experience regularization over time. [0023] In one or more embodiments, independent of the selection of the ventricle for an ATP that presents the lower heart rate, the therapy device may include the evaluation control unit that may be part of the therapy control unit, such that, during charging of one or more shock capacitors for defibrillation therapy, the evaluation control unit may continuously scan one or both ventricle channels after regularization of the rhythm and, in the case of regularization (for example using a stability criterion), may deliver an ATP attempt during the charging of the one or more shock capacitors in the respective ventricle channel. [0024] In at least one embodiment, the right-ventricular stimulation unit and the left-ventricular stimulation unit may include the one or more shock capacitors that store energy for a defibrillation shock, or are connected thereto. In one or more embodiments, the therapy control unit, during the charging of the one or more shock capacitors for defibrillation therapy, may analyze the signals representing the course over time of the electric potentials in the heart, or the signals derived therefrom, with regard to a regularization of the rhythm represented by the signals. In at least one embodiment, where appropriate, the therapy control unit may detect regularization during the charging of the one or more shock capacitors and therefrom may trigger an antitachycardia stimulation via the stimulation electrode assigned to the same ventricle as the sensing electrode via which the signals representing a regularized rhythm are recorded. [0025] In one or more embodiments, a defibrillation shock may be avoided at the last moment and, where appropriate, complete charging of the one or more shock capacitors may also be avoided, such that energy is saved and the patient is saved from a painful defibrillation shock. [0026] In at least one embodiment, the therapy control unit may carry out a stability evaluation of the rhythm represented by the signals representing the course over time of the electric potentials in the heart or the signals derived therefrom, and may trigger an antitachycardia stimulation via the stimulation electrode that is assigned to the same ventricle as the sensing electrode via which the signals representing a stable or more stable rhythm are recorded (for example using the stability criterion for the selection of the therapy channel). [0027] In one or more embodiments, the selection of the therapy channel (such as the right-ventricular stimulation unit and/or the left-ventricular stimulation unit via which an ATP is delivered) may be dependent on one or more of the heart rate detected via a respective sensing channel (such as the at least one right-ventricular or the at least one left-ventricular sensing electrode assigned to the respective ventricle), and on the stability of the rhythm represented by the detected signals. In at least one embodiment, the therapy control unit may trigger an antitachycardia stimulation via the at least one right-ventricular or the at least one left-ventricular stimulation electrode that is assigned to the same ventricle as the at least one right-ventricular or the at least one left-ventricular sensing electrode, via which signals representing a stable or more stable rhythm are recorded, even independently of whether signals representing a slower rhythm are recorded via the respective sensing electrode. [0028] According to one or more embodiments, the therapy control unit may use the frequency criterion preferentially or exclusively when selecting the therapy channel, or may use the stability criterion preferentially or exclusively. In at least one embodiment, the therapy control unit may apply the frequency criterion when selecting the therapy channel and may additionally apply the stability criterion. In one or more embodiments, the therapy control unit, in the event of a dissimilar tachycardia, may initially determine the sensing electrode via which the lower heart rate is detected, and may then check whether the signals detected via the respective sensing electrode, of the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode, represent a sufficiently stable rhythm. In at least one embodiment, the sufficiently stable rhythm may be a more stable or similarly stable rhythm compared to the signals recorded via the other sensing electrode of the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode. [0029] By way of one or more embodiments of the invention, the therapy control unit may, in the event of a dissimilar tachycardia, trigger one or more antitachycardia stimulations and may suppress a delivery of a defibrillation shock provided the signals detected via one or more of the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode represent a stable rhythm. In at least one embodiment, one or more ATP attempts may be provided instead of shock therapy, when one of the ventricle sides, of the right ventricle and the left ventricle, has a stable rhythm. [0030] In at least one embodiment, the therapy control unit may determine whether the signals from one or more of the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode represent a rhythm above a programmable limit value. If so, in one or more embodiments of the invention, the therapy control unit may trigger only a single individual antitachycardia stimulation and may trigger simultaneously or immediately thereafter a charging process by a shock capacitor, of the one or more shock capacitors, for a defibrillation shock. In one or more embodiments, if one of the ventricle sides is already located in the VF zone or above a programmable limit value, only an individual ATP attempt is delivered, and the charging process for defibrillation is started simultaneously or immediately thereafter. [0031] In one or more embodiments, the therapy control unit may check a success of the triggered antitachycardia stimulation during the charging of the one or more shock capacitors and, when the therapy control unit detects success of the triggered antitachycardia stimulation, the therapy control unit may suppress a delivery of the defibrillation shock. In one or more embodiments, the success of the ATP attempt may be evaluated during the charging of the one or more shock capacitors or before shock delivery, such as an ATP one shot. [0032] In at least one embodiment, the implantable heart therapy device may include an implantable biventricular cardioverter-defibrillator (ICD), wherein the ICD may include a metal housing and a terminal housing. In one or more embodiments, the metal housing may include the therapy control unit, the left-ventricular stimulation unit, the right-ventricular stimulation unit, and one or more electrical components including the one or more shock capacitors. In at least one embodiment, the terminal housing may be connected to electrode lines, wherein the electrode lines may include the at least one right-ventricular sensing electrode, the left-ventricular sensing electrode, the right-ventricular stimulation electrode and the left-ventricular stimulation electrode. BRIEF DESCRIPTION OF THE DRAWINGS [0033] The above and other aspects, features and advantages of at least one embodiment of the invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein: [0034] FIG. 1 shows an example of dissimilar ventricular tachyarrhythmia. [0035] FIG. 2 shows an implantable heart therapy device, such as an implantable heart stimulator, as a biventricular cardiac pacemaker with a right-ventricular defibrillation shock coil, according to at least one embodiment of the invention. [0036] FIG. 3 shows a simplified block diagram with components of the implantable heart stimulator of FIG. 2 , according to at least one embodiment of the invention. [0037] FIG. 4 shows a biventricular three-chamber cardiac pacemaker and an implantable cardioverter-defibrillator (ICD) as the implantable heart stimulator, according to at least one embodiment of the invention. [0038] FIG. 5 shows an example of an induced dissimilar ventricular fibrillation and corresponding marker signals generated by the implantable heart therapy device, according to at least one embodiment of the invention. [0039] FIG. 6 shows a flow chart for therapy management in the event of dissimilar ventricular tachycardias according to at least one embodiment of the invention. [0040] FIG. 7 shows an example of successful termination of dissimilar ventricular tachycardia, according to at least one embodiment of the invention. [0041] FIG. 8 shows an example of an ATP in the event of identified regularization of a VF, according to at least one embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION [0042] The following description is of the best mode presently contemplated for carrying out at least one embodiment of the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the invention. The scope of the invention should be determined with reference to the claims. [0043] FIG. 1 shows an example of a dissimilar ventricular tachyarrhythmia. As shown in FIG. 1 , the rhythm changes in the right ventricle (RV) from a stable VT over a short phase of VF to slower VT 110 , and at the same time the rhythm in the LV channel changes at a later moment in time from a stable VT to a lasting VF 120 , which is not sensed with a purely right-ventricular detection and may lead to an incorrect choice of therapy. [0044] FIG. 2 shows a biventricular cardiac pacemaker-defibrillator (ICD or CRT-D), having a right-ventricular defibrillation shock coil, as an implantable heart therapy device (or heart stimulator) 10 , according to at least one embodiment of the invention. In one or more embodiments, the implantable heart therapy device 10 includes electrode lines 16 and 30 connected thereto. The implantable heart therapy device 10 , in at least one embodiment, is connected via the electrode lines 16 and 30 to stimulation electrodes 18 and 20 , and to sensing electrode 32 and 34 , in the right and left ventricle of a heart respectively. In one or more embodiments, the heart therapy device may deliver stimulation pulses to the heart and record electric potentials from the heart. [0045] In at least one embodiment, the heart therapy device 10 may include a housing 42 , such as a metal housing, with a terminal block or header 11 for the electrode lines 16 and 30 . [0046] The electrode lines 16 and 30 , in at least one embodiment, are electrically connected via plug connections to contact sockets in the header (terminal housing) 11 of the heart stimulator 10 . In one or more embodiments, the electrode lines 16 and 30 may be connected to one or more electronic components inside a hermetically tight metal housing 42 of the heart stimulator 10 . The one or more electronic components, according to at least one embodiment, schematically illustrated in FIG. 3 , may determine the operating principles of the heart stimulator 10 . [0047] In one or more embodiments, the electrode line 16 is a right-ventricular electrode line and has at its distal end a right-ventricular tip electrode pole RV Tip 18 , and in a direct or indirect vicinity thereof, a right-ventricular ring electrode pole RV Ring 20 . In at least one embodiment, both electrode poles may be arranged in the apex of the right ventricle of the heart and may be used for right-ventricular sensing and stimulation, and thus form a sensing and stimulation electrode. In one or more embodiments, the sensing may be carried out via the ring electrode pole RV Ring 20 and tip electrode pole RV Tip 18 as a bipolar electrode pole, wherein stimulation pulses may be delivered via the tip electrode pole RV Tip 18 alone. In one or more embodiments, the electrode line 16 may include a right-ventricular shock coil RV Shock 38 as a large-area electrode pole that delivers defibrillation shocks. In at least one embodiment, the housing 42 may be a counter electrode. [0048] In at least one embodiment, the heart therapy device 10 may include a left-ventricular electrode line 30 implanted via a coronary sinus, and may include a bipolar electrode pole that senses and stimulates the left ventricle. [0049] In one or more embodiments, the left-ventricular electrode line 30 may include a bipolar stimulation and sensing electrode at its distal end. In at least one embodiment, the bipolar stimulation and sensing electrode may include a distal tip electrode pole LV Tip 34 , and in the direct or indirect vicinity thereof, a left-ventricular ring electrode pole LV Ring 32 . In one or more embodiments, the two electrode poles LV Tip 34 and LV Ring 32 may be used for right-ventricular sensing and stimulation, and may include a sensing and stimulation electrode. In at least one embodiment, the sensing may be carried out via the ring electrode pole LV Ring 32 and the tip electrode pole LV Tip 34 as a bipolar electrode pole, wherein left-ventricular stimulation pulses may be delivered via the tip electrode pole LV Tip 34 alone. In one or more embodiments, the left-ventricular electrode line 30 may be guided from the right atrium 26 of the heart 12 via the coronary sinus into a lateral vein branching therefrom, also referred to as the coronary sinus electrode line or CS electrode line. [0050] FIG. 3 shows components, such as key functional units, of the heart stimulator 10 . As shown in FIG. 3 , additional components are illustrated via dashed lines, as may be provided in at least one embodiment of the invention. [0051] By way of one or more embodiments, as shown on the left-hand side, electrical terminals for the various electrode poles 18 , 20 , 32 , 34 and 38 are illustrated. The shock electrode (shock coil) 38 , in at least one embodiment, is connected to a shock pulse generator 50 . In one or more embodiments, the shock pulse generator 50 may be connected to a control unit 54 , which controls the shock pulse generator 50 , as required, to generate and deliver a cardioversion or defibrillation shock. In at least one embodiment, the control unit 54 acts as a therapy device control unit 54 ′. The therapy device control 54 ′ may be connected, for example, to the shock pulse generator 50 , to a right-ventricular stimulation unit 56 , and to a left-ventricular stimulation unit 64 . [0052] The control unit 54 , in at least one embodiment, may include a tachycardia identification unit 90 and a dislocation identification unit 92 . [0053] By way of one or more embodiments, the terminal for the right-ventricular tip electrode pole RV Tip, and the terminal for the right-ventricular ring electrode pole RV Ring, are each connected to both the right-ventricular stimulation unit 56 and to a right-ventricular sensing unit 58 . Both the right-ventricular stimulation unit 56 and the right-ventricular sensing unit 58 , in one or more embodiments, are each connected to the control unit 54 . [0054] According to at least one embodiment, the right-ventricular stimulation unit 56 , following a control signal of the control unit 54 , may generate a right-ventricular stimulation pulse and may deliver the right-ventricular stimulation pulse via the terminals for the right-ventricular ring electrode pole and the right-ventricular tip electrode pole. In one or more embodiments, the housing 42 of the heart stimulator 10 may form a neutral electrode, and the right-ventricular stimulation unit 56 may be connected to the terminal for the right-ventricular tip electrode pole RV Tip and to the housing 42 as another electrode to deliver a stimulation pulse. In at least one embodiment, the right-ventricular stimulation pulse differs from a defibrillation shock in that the stimulation pulse has a much lower pulse intensity, such that, by contrast to a defibrillation shock, it does not excite the entire heart tissue (myocardium) of a heart chamber in one attempt, but only excites the heart muscle cells in the direct vicinity of the right-ventricular tip electrode pole 18 . In one or more embodiments, the excitation then propagates further as a result of natural conduction over the entire ventricle and thus ensures a stimulated contraction of the ventricle. [0055] In at least one embodiment, the right-ventricular sensing unit 58 may first amplify, using an input amplifier, and then filter electric potentials applied across the terminal for the right-ventricular ring electrode pole RV Ring and the right-ventricular tip electrode pole RV Tip. By way of one or more embodiments, the right-ventricular sensing unit 58 may evaluate the course of the electric signals applied across its inputs in such a way that the right-ventricular sensing unit 58 automatically detects a natural (intrinsic) beat, such an as automatic contraction of the right ventricle. In at least one embodiment, the evaluation may be achieved, for example, by comparing the course of the signal applied across the inputs of the right-ventricular sensing unit 58 to a threshold value. In one or more embodiments, the largest amplitude of the signal is in the form of an R-spike, which is characteristic for a natural contraction of the right ventricle and which may be detected by comparison with a threshold value. In at least one embodiment, the right-ventricular sensing unit 58 , therefrom, may output a corresponding output signal (for example a marker signal), indicating a natural contraction of the right ventricle, to the control unit 54 , the tachycardia identification unit 90 and to the dislocation identification unit 92 thereof. [0056] In one or more embodiments, the terminal for the left-ventricular tip electrode pole LV Tip and the terminal for the left-ventricular ring electrode pole LV Ring are also connected to the left-ventricular stimulation unit 64 and a left-ventricular sensing unit 66 . In at least one embodiment, the left-ventricular stimulation unit 64 and the left-ventricular sensing unit 66 may be connected to the control unit 54 . In one or more embodiments, both the left-ventricular stimulation unit 64 and the left-ventricular sensing unit 66 may function similarly to the stimulation units 56 and 60 and sensing units 58 and 62 as described above. [0057] In at least one embodiment, the heart stimulator 10 may include an activity sensor 72 connected to the control unit 54 and generally includes timer 82 . The activity sensor 72 , in one or more embodiments, may detect a signal, for example a motion signal, dependent on the physical activity of a patient and may output a corresponding signal, indicating the physical activity of the patient, to the control unit 54 . As such, in at least one embodiment, the control unit 54 may adapt the timing of the stimulation pulse to the demand of the patient (hemodynamic demand). [0058] According to at least one embodiment, the heart stimulator 10 may include a memory unit 80 , connected to the control unit 54 , that stores signals generated or evaluated by the control unit 54 . In one or more embodiments, the memory unit 80 may store control programs for the control unit 54 in modifiable form. In at least one embodiment, the control unit 54 may be connected to a timer 82 . [0059] By way of one or more embodiments, the heart stimulator 10 may include at least one bidirectional telemetry interface 84 to transfer stored data from the implant 10 to an external device 100 and, vice versa, to also receive program settings and therapy commands from the external device 100 . [0060] FIG. 4 shows a biventricular three-chamber cardiac pacemaker and implantable cardioverter-defibrillator (ICD) as an implantable cardiac stimulator. As shown in FIG. 4 , the implantable cardiac stimulator 10 ′, in at least one embodiment, is connected via its terminal block 11 (header) to one or more of a right-ventricular electrode line 16 , a left-ventricular electrode line 30 , and a right-atrial electrode line 14 . [0061] In one or more embodiments, at least one of the electrode lines 16 , 30 and 14 , may be implanted permanently in the heart 12 . In at least one embodiment, the right-ventricular electrode line 16 has at the distal end a bipolar stimulation and sensing electrode with a tip electrode pole RV Tip 18 and a ring electrode pole RV Ring 20 . According to at least one embodiment, the electrode line 16 may include a distal shock coil RV Coil 38 and additionally a proximal shock coil SVC Coil 40 . The distal shock coil RV Coil 38 , in at least one embodiment, may be arranged such that it is located in the right ventricle 28 . The proximal shock coil SVC Coil 40 , in at least one embodiment, may be located in the upper part of the right atrium 26 or in the superior vena cava (precava). [0062] By way of one or more embodiments, the electrode line 14 is an atrial electrode line and may include at the distal end a bipolar stimulation and sensing electrode, formed by a tip electrode pole RA Tip 22 and a ring electrode pole RA Ring 24 . The electrode line 14 is implanted in the right atrium 26 . [0063] As shown in FIG. 4 , according to one or more embodiments, the left-ventricular electrode line 30 may include a left-ventricular shock coil 36 that delivers defibrillation shocks to the left ventricle. In at least one embodiment, the shock coil 36 may reach out from the left ventricle 44 as far as the left atrium 46 . In at least one embodiment, the implantable cardiac stimulator 10 ′ may include a second electrode, to deliver a shock, as the electrically active housing 42 of the implant 10 ′. [0064] As shown from FIG. 3 , in at least one embodiment of the invention, according to the components illustrated in a dotted manner, the terminal for the right-atrial tip electrode pole and the terminal for the right-atrial ring electrode pole may be connected both to a right-atrial stimulation unit 60 and to a right-atrial sensing unit 62 , which are each in turn connected to the control unit 54 . In one or more embodiments, the right-atrial stimulation unit 60 may generate stimulation pulses, of which the intensity is sufficient to excite the right-atrial myocardium. In at least one embodiment, the right-atrial stimulation pulses may have pulse intensity that is different from the right-ventricular stimulation pulses. The right-atrial sensing unit 62 , in at least one embodiment, may detect a P-wave from the course of the differential signal applied across the inputs thereof, wherein the P-wave represents a natural (intrinsic) contraction of the right atrium. If the right-atrial sensing unit 62 detects a corresponding P-wave, in at least one embodiment of the invention, it generates an output signal and forwards the output signal to the control unit 54 , wherein the output signal represents a natural contraction of the right atrium. [0065] As also shown in FIG. 3 , according to the components illustrated in a dotted manner, the left-ventricular shock coil 36 , as illustrated in FIG. 4 , may be connected to the shock pulse generator 50 via a terminal LV-COIL and an electrode selection unit 52 . Using the electrode selection unit 52 , in one or more embodiments, the control unit 54 may select two or more electrodes (including the conductive housing 42 ) via which a shock is delivered. [0066] According to the heart therapy devices illustrated in FIGS. 2 to 4 , according to at least one embodiment of the invention, the tachycardic ventricular dysrhythmias may be classified by the right-ventricular 16 and/or the left-ventricular electrode line 30 , primarily via the sensed heartbeats, wherein the frequency and frequency stability of both sides of the ventricle may be evaluated during therapy selection. If the frequencies of both ventricles differ significantly, in one or more embodiments, the slower rhythm is thus evaluated in terms of frequency and optionally stability. In at least one embodiment, an ATP is always delivered to the slower ventricle side, only if the ventricle side has a frequency below a programmable frequency limit, or if a stability is detected on the respective ventricle side. [0067] FIG. 5 shows an example of an induced dissimilar ventricular tachycardia. As shown in FIG. 5 , an unstable and very quick rhythm corresponding to a ventricular fibrillation is shown in the right-ventricular IEGM (RV), wherein a tachycardia with comparatively regular cycle length is shown in the left ventricle (LV). [0068] In at least one embodiment, a dissimilar tachycardia may be classified by conventional ICD systems as ventricular fibrillation (VF; see “RV” line) and may always initiate defibrillation shock therapy. [0069] According to one or more embodiments, a dysrhythmia may be treated successfully and painlessly using antitachycardia stimulation, if the ATP is applied to the slower, stable ventricle side. In at least one embodiment, an electrophysiological explanatory model may be based on a myocardial conduction and refractory period structure, for example in the left ventricle, wherein the right-ventricular structure may already demonstrate disassociated conduction and refractory period conditions. In one or more embodiments, as shown in FIG. 5 , if the left-hand VT is successfully terminated by an ATP, the dysrhythmia may also terminate on the right-hand side with a high level of probability. [0070] FIG. 6 shows a flow chart for therapy management in the event of dissimilar ventricular tachycardias, according to at least one embodiment of the invention. [0071] In one or more embodiments, when a tachycardia is identified, the therapy control unit may first check for a dissimilarity (RV≠LV). If the rhythm is dissimilar, in at least one embodiment, then the therapy control unit may check which ventricle frequency, of the left ventricle and the right ventricle, is slower (RV>LV). In one or more embodiments, for the slower side, the therapy control unit may check whether the frequency already lies within the VF-zone requiring a shock (RV/LV>VF). If the frequency does not already lie in the VF-zone requiring a shock, by way of at least one embodiment, an ATP is delivered to the respective ventricle side. In at least one embodiment, if the rhythm on the slower ventricle side is also already within the VF-zone, a shock ( ) may then be immediately delivered if the rhythm is unstable (RV/LV unstab.), otherwise an ATP attempt may be delivered on the respective side. As such, in one or more embodiments, the therapy control unit may start the charging process for a shock either thereafter, or during the ATP delivery (such as ATP one shot). [0072] FIG. 7 shows an example of successful termination of a dissimilar VT. As shown in FIG. 7 , the frequency of the left-ventricular tachycardia may be twice as high as that of the right-ventricular VT, may fall within the VF-zone, and may be treated by shock therapy. According to at least one embodiment of the invention, an ATP (*Burst), delivered to the slower ventricle side (for example shown as the RV in FIG. 7 ), may successfully terminate the ventricular tachycardia, and therefore delivery of a shock is not needed. [0073] FIG. 8 shows an example of an ATP in the event of identified regularization of a VF, according to at least one embodiment of the invention. As shown in FIG. 8 , according to operating principles of the heart therapy device 10 and 10 ′, the tachycardia identification unit 90 may continuously scan one or both ventricle channels after regularization of the rhythm during the charging of the one or more shock capacitors for defibrillation therapy. In one or more embodiments, the control unit 54 , in the event of regularization (for example stability criterion), may trigger an ATP attempt during the charging of the one or more shock capacitors in the respective ventricle channel. FIG. 8 shows an irregular ventricular fibrillation, wherein according to at least one embodiment, after detection, may lead to charging of the one or more shock capacitors. In one or more embodiments, while the one or more shock capacitors are being charged, the rhythm in both ventricles, the left ventricle and the right ventricle, are checked for regularization, and, in the event of identified regularization, an ATP attempt may be delivered in the ventricle channel first classified as being regular (shown as the RV in FIG. 8 ). As shown in FIG. 8 , according to at least one embodiment, the ATP is successful and shock delivery is therefore inhibited. [0074] In one or more embodiments, a stability criterion, optionally with a programmable upper frequency limit, may be used as a criterion for regularization. [0075] In at least one embodiment, using the stability criterion may reduce unnecessary shock deliveries, even in a single-chamber system. [0076] One or more embodiments of the invention enable optimization of the therapy efficiency of antitachycardia stimulation, such as in the case of dissimilar and quick ventricular dysrhythmias, and thus serve to reduce the unnecessary shock deliveries in ICD therapy. [0077] It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teaching. The disclosed examples and embodiments are presented for purposes of illustration only. Other alternate embodiments may include some or all of the features disclosed herein. Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention.
An implantable heart therapy device connected to at least one right-ventricular electrode and one left-ventricular electrode that sense and stimulate the heart. The at least one right-ventricular and left-ventricular electrodes are each connected to a tachycardia identification unit, wherein the identification unit identifies ventricular tachycardias, and simultaneously evaluates the heart rate at the right-ventricular and at the left-ventricular electrodes. The implantable heart therapy device includes a right-ventricular stimulation unit that delivers antitachycardia stimulation to the right-ventricular electrode, a left-ventricular stimulation unit that delivers antitachycardia stimulation to the left-ventricular electrode, and a therapy control unit that assigns the stimulation location for the antitachycardia stimulation to the slower ventricle side if a dissimilar tachycardia is present.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "[0001] This application claims the benefit of U.S. Provisional Patent Application 61/847,093, filed on 17 Jul. 2013, and U.S. Provisional Patent Application 61/865,625, filed on 14 Aug. 2013, the specifications of which are hereby incorporated herein by reference.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] Embodiments of the invention generally relate to an implantable heart therapy device having a therapy control unit that includes a tachycardia identification unit.", "The heart therapy device also includes a right-ventricular stimulation unit and a left-ventricular stimulation unit, wherein both the right-ventricular stimulation unit and the left-ventricular stimulation unit are connected to the therapy control unit.", "The therapy control unit triggers antitachycardia stimulation (ATP).", "[0004] 2.", "Description of the Related Art [0005] European Patent 1 857 140 to Doerr et al.", ", entitled “Heart Stimulator”, discloses a heart therapy device having a stimulation unit that is connected or can be connected to a stimulation electrode in order to stimulate a ventricle of a heart.", "The stimulation unit, of Doerr et al.", ", may generate both stimulation pulses and defibrillation shocks, and may include at least one high-voltage capacitor, in which the electrical energy necessary for a defibrillation shock is stored.", "[0006] Generally, heart therapy devices may include a detector that processes physiological signals received from the heart and, on the basis thereof, detects the presence of an acute ventricular tachycardia or fibrillation.", "Typically, heart therapy devices may also include a control unit connected to the detector and the stimulation unit, wherein the control unit is responsive to an output signal of the detector to control the stimulation unit to deliver a sequence of stimulation pulses or to deliver a defibrillation shock forming an antitachycardia therapy.", "The heart therapy device of Doerr et al.", "enables therapy delivery to a right ventricle of the heart.", "[0007] Generally, heart therapy devices may be referred to as implantable cardioverter-defibrillators (ICD).", "Typically, heart therapy devices referred to herein are primarily implantable heart therapy devices that are able to treat tachycardia of the heart.", "[0008] Generally, the term “tachycardias”", "includes both tachycardias represented by a stable heartbeat with pathologically high frequency, and also fibrillations.", "Therapies delivered by a heart stimulator, generally, include an antitachycardia stimulation or a defibrillation shock.", "[0009] A defibrillation shock is typically an electrical pulse delivered to the heart and has sufficiently high voltage and energy to fully excite a heart chamber affected by fibrillation to therefore make the heart chamber refractory.", "Therefore, re-entrant excitation pulses, typical for fibrillations, are interrupted.", "In the case of tachycardia wherein a ventricle is affected, the tachycardia is often also referred to as ventricular tachycardia and is abbreviated by VT (in contrast to ventricular fibrillation VF).", "Generally, successful therapy is often possible using antitachycardia stimulation (antitachyarrhythmia pacing: ATP).", "Generally, with antitachycardia stimulation, the heart stimulator outputs a sequence of stimulation pulses, of which the energy is significantly lower than the energy of a defibrillation shock and which are not painful.", "Typically, with antitachycardia stimulation, such stimulation pulses of comparatively low energy are delivered with a frequency that is greater than the frequency of the determined tachycardia.", "Generally, tachycardia may be stopped in this way without a patient suffering from pain or without the energy demand being particularly high.", "[0010] Typical therapy devices generally deliver stimulation pulses to one or both ventricles of a heart, to the left ventricle (LV) and/or to the right ventricle (RV).", "Such therapy devices are generally referred to as biventricular therapy devices.", "[0011] Generally, previous ICD systems available on the market may operate exclusively with a right-ventricular VT/VF identification channel for the tachycardia identification and for the corresponding therapy selection.", "Typically, the stimulation location of the ATP may be programmed statically (RV, LV, BiV).", "[0012] Generally, ICD systems may also provide, in the VF zone, an ATP therapy attempt, which is delivered immediately before or with the onset of charging, but only when the right-ventricular rhythm meets a frequency and/or stability criterion at the same time;", "such as an ATP one shot.", "[0013] Typically, purely right-ventricular sensing used with current ICD systems may have the disadvantage that, in the event of dissimilar ventricular tachyarrhythmia, an incorrect therapy may be selected.", "If, for example, the rhythm in the right ventricle is already in a VF zone and is unstable, but the left ventricle is still stable, generally, the selection of a defibrillation shock is preferred over an ATP, although clinical observations show that an ATP delivery, for example in the left ventricle, may have a higher therapy success rate.", "[0014] Generally, a further disadvantage of current systems includes the exclusive use of right-ventricular sensing for synchronization of a left-ventricular ATP.", "Typically, the exclusive use of right-ventricular sensing may be the reason why no clinical studies are known that demonstrate an advantage of left-ventricular ATP.", "[0015] Generally, one-time ATP attempts in the VF zone do not take into account the left-ventricular rhythm and also do not take into account potential rhythm regularization during the charging time, and therefore potentially effective ATP attempts are not delivered.", "BRIEF SUMMARY OF THE INVENTION [0016] At least one embodiment of the invention includes an implantable therapy device that enables high therapy efficiency of antitachycardia stimulation (ATP).", "[0017] One or more embodiments of the invention include an implantable heart therapy device having a therapy control unit, which includes a tachycardia identification unit connected, at least indirectly, to at least one right-ventricular sensing electrode and at least one left-ventricular sensing electrode.", "In at least one embodiment of the invention, the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode may feed at least one signal from the heart's right ventricle and at least one signal from the heart's left ventricle, respectively, to the tachycardia identification unit.", "In one or more embodiments, the signals represent a course over time of electrical potentials in the heart.", "During operation, in one or more embodiments, the signals representing a course over time of electric potentials in the heart or signals derived therefrom are fed to the tachycardia identification unit.", "By way of at least one embodiment, the tachycardia identification unit may evaluate the signals fed thereto and/or the course over time thereof, and may generate a tachyarrhythmia signal if the (fed) signal meets predefined criteria.", "In at least one embodiment, the tachycardia identification unit may simultaneously evaluate the heart rate at the at least one right-ventricular sensing electrode and at the at least one left-ventricular sensing electrode to identify ventricular tachycardia.", "[0018] According to one or more embodiments, the implantable heart therapy device may include a right-ventricular stimulation unit and a left-ventricular stimulation unit connected to the therapy control unit.", "The right-ventricular stimulation unit and the left-ventricular stimulation unit, in at least one embodiment, may, in combination with the therapy control unit, generate stimulation pulses for one or more of a right-ventricular and a left-ventricular antitachycardia stimulation therapy (ATP).", "In at least one embodiment, the right-ventricular stimulation unit and the left-ventricular stimulation unit may deliver the stimulation pulses via the at least one right-ventricular stimulation electrode or the left-ventricular stimulation electrode connected thereto, respectively.", "[0019] In one or more embodiments, the tachycardia identification unit may detect and determine a dissimilar tachycardia that is greater than the heart rates sensed via the right-ventricular sensing electrode and via the left-ventricular sensing electrode.", "In at least one embodiment, the therapy control unit may control a delivery of the stimulation pulses for one or more of the right-ventricular and the left ventricular antitachycardia stimulation via the at least one right-ventricular or the at least one left-ventricular stimulation electrode, such that the stimulation pulses for antitachycardia stimulation are delivered via the stimulation electrode which is assigned to the same ventricle as the at least one right-ventricular sensing electrode or the at least one left-ventricular sensing electrode via which, in the event of the dissimilar tachycardia, at least one signal representing the lower heart rate is established or detected.", "In at least one embodiment, the control of the delivery of the stimulation pulses may be based on a frequency criterion for a selection of a therapy channel, wherein the therapy channel denotes a stimulation unit, of one or more of the right-ventricular stimulation unit and the left-ventricular stimulation unit, assigned to a respective ventricle.", "[0020] At least one embodiment of the invention uses biventricular sensing to optimize the therapy efficiency of the antitachycardia stimulation (ATP) to automatically determine the (ATP) stimulation location (RV, LV) in patients with dissimilar ventricular tachycardias.", "The heart therapy device, according to one or more embodiments of the invention, enable a considerable increase in the efficiency of the antitachycardia stimulation and thus simultaneously reduce the need for defibrillation therapies, for example shock reduction.", "[0021] The heart therapy device, according to at least one embodiment of the invention, may include an implantable defibrillator connected to at least one right-ventricular electrode and to at least one left-ventricular electrode that sense and stimulate the heart.", "In one or more embodiments, each of the at least one right-ventricular electrode and the at least one left-ventricular electrode are connected to the tachycardia identification unit.", "In at least one embodiment, the tachycardia identification unit may identify ventricular tachycardias, and may evaluate the heart rate at the at least one right-ventricular and at the at least one left-ventricular electrode simultaneously.", "The heart therapy device, such as the implantable defibrillator, in at least one embodiment, includes a right-ventricular stimulation unit that delivers antitachycardia stimulation to the right-ventricular electrode, a left-ventricular stimulation unit that delivers antitachycardia stimulation to the left-ventricular electrode.", "In one or more embodiments, the heart therapy device may include an evaluation control unit that may be part of the therapy control unit wherein the evaluation control unit may determine the stimulation location for the antitachycardia stimulation on the slower ventricle side when dissimilar tachycardia is present.", "[0022] By one or more embodiments of the invention, the heart therapy device enables the therapy efficiency of the ATP to rise significantly and thus reduces the number of necessary shock deliveries.", "At least one embodiment of the invention includes a 3-chamber ICD, wherein a considerable proportion of episodes with dissimilar ventricular tachycardias may exist, and the progressions of a rhythm of quick tachycardias may also experience regularization over time.", "[0023] In one or more embodiments, independent of the selection of the ventricle for an ATP that presents the lower heart rate, the therapy device may include the evaluation control unit that may be part of the therapy control unit, such that, during charging of one or more shock capacitors for defibrillation therapy, the evaluation control unit may continuously scan one or both ventricle channels after regularization of the rhythm and, in the case of regularization (for example using a stability criterion), may deliver an ATP attempt during the charging of the one or more shock capacitors in the respective ventricle channel.", "[0024] In at least one embodiment, the right-ventricular stimulation unit and the left-ventricular stimulation unit may include the one or more shock capacitors that store energy for a defibrillation shock, or are connected thereto.", "In one or more embodiments, the therapy control unit, during the charging of the one or more shock capacitors for defibrillation therapy, may analyze the signals representing the course over time of the electric potentials in the heart, or the signals derived therefrom, with regard to a regularization of the rhythm represented by the signals.", "In at least one embodiment, where appropriate, the therapy control unit may detect regularization during the charging of the one or more shock capacitors and therefrom may trigger an antitachycardia stimulation via the stimulation electrode assigned to the same ventricle as the sensing electrode via which the signals representing a regularized rhythm are recorded.", "[0025] In one or more embodiments, a defibrillation shock may be avoided at the last moment and, where appropriate, complete charging of the one or more shock capacitors may also be avoided, such that energy is saved and the patient is saved from a painful defibrillation shock.", "[0026] In at least one embodiment, the therapy control unit may carry out a stability evaluation of the rhythm represented by the signals representing the course over time of the electric potentials in the heart or the signals derived therefrom, and may trigger an antitachycardia stimulation via the stimulation electrode that is assigned to the same ventricle as the sensing electrode via which the signals representing a stable or more stable rhythm are recorded (for example using the stability criterion for the selection of the therapy channel).", "[0027] In one or more embodiments, the selection of the therapy channel (such as the right-ventricular stimulation unit and/or the left-ventricular stimulation unit via which an ATP is delivered) may be dependent on one or more of the heart rate detected via a respective sensing channel (such as the at least one right-ventricular or the at least one left-ventricular sensing electrode assigned to the respective ventricle), and on the stability of the rhythm represented by the detected signals.", "In at least one embodiment, the therapy control unit may trigger an antitachycardia stimulation via the at least one right-ventricular or the at least one left-ventricular stimulation electrode that is assigned to the same ventricle as the at least one right-ventricular or the at least one left-ventricular sensing electrode, via which signals representing a stable or more stable rhythm are recorded, even independently of whether signals representing a slower rhythm are recorded via the respective sensing electrode.", "[0028] According to one or more embodiments, the therapy control unit may use the frequency criterion preferentially or exclusively when selecting the therapy channel, or may use the stability criterion preferentially or exclusively.", "In at least one embodiment, the therapy control unit may apply the frequency criterion when selecting the therapy channel and may additionally apply the stability criterion.", "In one or more embodiments, the therapy control unit, in the event of a dissimilar tachycardia, may initially determine the sensing electrode via which the lower heart rate is detected, and may then check whether the signals detected via the respective sensing electrode, of the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode, represent a sufficiently stable rhythm.", "In at least one embodiment, the sufficiently stable rhythm may be a more stable or similarly stable rhythm compared to the signals recorded via the other sensing electrode of the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode.", "[0029] By way of one or more embodiments of the invention, the therapy control unit may, in the event of a dissimilar tachycardia, trigger one or more antitachycardia stimulations and may suppress a delivery of a defibrillation shock provided the signals detected via one or more of the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode represent a stable rhythm.", "In at least one embodiment, one or more ATP attempts may be provided instead of shock therapy, when one of the ventricle sides, of the right ventricle and the left ventricle, has a stable rhythm.", "[0030] In at least one embodiment, the therapy control unit may determine whether the signals from one or more of the at least one right-ventricular sensing electrode and the at least one left-ventricular sensing electrode represent a rhythm above a programmable limit value.", "If so, in one or more embodiments of the invention, the therapy control unit may trigger only a single individual antitachycardia stimulation and may trigger simultaneously or immediately thereafter a charging process by a shock capacitor, of the one or more shock capacitors, for a defibrillation shock.", "In one or more embodiments, if one of the ventricle sides is already located in the VF zone or above a programmable limit value, only an individual ATP attempt is delivered, and the charging process for defibrillation is started simultaneously or immediately thereafter.", "[0031] In one or more embodiments, the therapy control unit may check a success of the triggered antitachycardia stimulation during the charging of the one or more shock capacitors and, when the therapy control unit detects success of the triggered antitachycardia stimulation, the therapy control unit may suppress a delivery of the defibrillation shock.", "In one or more embodiments, the success of the ATP attempt may be evaluated during the charging of the one or more shock capacitors or before shock delivery, such as an ATP one shot.", "[0032] In at least one embodiment, the implantable heart therapy device may include an implantable biventricular cardioverter-defibrillator (ICD), wherein the ICD may include a metal housing and a terminal housing.", "In one or more embodiments, the metal housing may include the therapy control unit, the left-ventricular stimulation unit, the right-ventricular stimulation unit, and one or more electrical components including the one or more shock capacitors.", "In at least one embodiment, the terminal housing may be connected to electrode lines, wherein the electrode lines may include the at least one right-ventricular sensing electrode, the left-ventricular sensing electrode, the right-ventricular stimulation electrode and the left-ventricular stimulation electrode.", "BRIEF DESCRIPTION OF THE DRAWINGS [0033] The above and other aspects, features and advantages of at least one embodiment of the invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein: [0034] FIG. 1 shows an example of dissimilar ventricular tachyarrhythmia.", "[0035] FIG. 2 shows an implantable heart therapy device, such as an implantable heart stimulator, as a biventricular cardiac pacemaker with a right-ventricular defibrillation shock coil, according to at least one embodiment of the invention.", "[0036] FIG. 3 shows a simplified block diagram with components of the implantable heart stimulator of FIG. 2 , according to at least one embodiment of the invention.", "[0037] FIG. 4 shows a biventricular three-chamber cardiac pacemaker and an implantable cardioverter-defibrillator (ICD) as the implantable heart stimulator, according to at least one embodiment of the invention.", "[0038] FIG. 5 shows an example of an induced dissimilar ventricular fibrillation and corresponding marker signals generated by the implantable heart therapy device, according to at least one embodiment of the invention.", "[0039] FIG. 6 shows a flow chart for therapy management in the event of dissimilar ventricular tachycardias according to at least one embodiment of the invention.", "[0040] FIG. 7 shows an example of successful termination of dissimilar ventricular tachycardia, according to at least one embodiment of the invention.", "[0041] FIG. 8 shows an example of an ATP in the event of identified regularization of a VF, according to at least one embodiment of the invention.", "DETAILED DESCRIPTION OF THE INVENTION [0042] The following description is of the best mode presently contemplated for carrying out at least one embodiment of the invention.", "This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the invention.", "The scope of the invention should be determined with reference to the claims.", "[0043] FIG. 1 shows an example of a dissimilar ventricular tachyarrhythmia.", "As shown in FIG. 1 , the rhythm changes in the right ventricle (RV) from a stable VT over a short phase of VF to slower VT 110 , and at the same time the rhythm in the LV channel changes at a later moment in time from a stable VT to a lasting VF 120 , which is not sensed with a purely right-ventricular detection and may lead to an incorrect choice of therapy.", "[0044] FIG. 2 shows a biventricular cardiac pacemaker-defibrillator (ICD or CRT-D), having a right-ventricular defibrillation shock coil, as an implantable heart therapy device (or heart stimulator) 10 , according to at least one embodiment of the invention.", "In one or more embodiments, the implantable heart therapy device 10 includes electrode lines 16 and 30 connected thereto.", "The implantable heart therapy device 10 , in at least one embodiment, is connected via the electrode lines 16 and 30 to stimulation electrodes 18 and 20 , and to sensing electrode 32 and 34 , in the right and left ventricle of a heart respectively.", "In one or more embodiments, the heart therapy device may deliver stimulation pulses to the heart and record electric potentials from the heart.", "[0045] In at least one embodiment, the heart therapy device 10 may include a housing 42 , such as a metal housing, with a terminal block or header 11 for the electrode lines 16 and 30 .", "[0046] The electrode lines 16 and 30 , in at least one embodiment, are electrically connected via plug connections to contact sockets in the header (terminal housing) 11 of the heart stimulator 10 .", "In one or more embodiments, the electrode lines 16 and 30 may be connected to one or more electronic components inside a hermetically tight metal housing 42 of the heart stimulator 10 .", "The one or more electronic components, according to at least one embodiment, schematically illustrated in FIG. 3 , may determine the operating principles of the heart stimulator 10 .", "[0047] In one or more embodiments, the electrode line 16 is a right-ventricular electrode line and has at its distal end a right-ventricular tip electrode pole RV Tip 18 , and in a direct or indirect vicinity thereof, a right-ventricular ring electrode pole RV Ring 20 .", "In at least one embodiment, both electrode poles may be arranged in the apex of the right ventricle of the heart and may be used for right-ventricular sensing and stimulation, and thus form a sensing and stimulation electrode.", "In one or more embodiments, the sensing may be carried out via the ring electrode pole RV Ring 20 and tip electrode pole RV Tip 18 as a bipolar electrode pole, wherein stimulation pulses may be delivered via the tip electrode pole RV Tip 18 alone.", "In one or more embodiments, the electrode line 16 may include a right-ventricular shock coil RV Shock 38 as a large-area electrode pole that delivers defibrillation shocks.", "In at least one embodiment, the housing 42 may be a counter electrode.", "[0048] In at least one embodiment, the heart therapy device 10 may include a left-ventricular electrode line 30 implanted via a coronary sinus, and may include a bipolar electrode pole that senses and stimulates the left ventricle.", "[0049] In one or more embodiments, the left-ventricular electrode line 30 may include a bipolar stimulation and sensing electrode at its distal end.", "In at least one embodiment, the bipolar stimulation and sensing electrode may include a distal tip electrode pole LV Tip 34 , and in the direct or indirect vicinity thereof, a left-ventricular ring electrode pole LV Ring 32 .", "In one or more embodiments, the two electrode poles LV Tip 34 and LV Ring 32 may be used for right-ventricular sensing and stimulation, and may include a sensing and stimulation electrode.", "In at least one embodiment, the sensing may be carried out via the ring electrode pole LV Ring 32 and the tip electrode pole LV Tip 34 as a bipolar electrode pole, wherein left-ventricular stimulation pulses may be delivered via the tip electrode pole LV Tip 34 alone.", "In one or more embodiments, the left-ventricular electrode line 30 may be guided from the right atrium 26 of the heart 12 via the coronary sinus into a lateral vein branching therefrom, also referred to as the coronary sinus electrode line or CS electrode line.", "[0050] FIG. 3 shows components, such as key functional units, of the heart stimulator 10 .", "As shown in FIG. 3 , additional components are illustrated via dashed lines, as may be provided in at least one embodiment of the invention.", "[0051] By way of one or more embodiments, as shown on the left-hand side, electrical terminals for the various electrode poles 18 , 20 , 32 , 34 and 38 are illustrated.", "The shock electrode (shock coil) 38 , in at least one embodiment, is connected to a shock pulse generator 50 .", "In one or more embodiments, the shock pulse generator 50 may be connected to a control unit 54 , which controls the shock pulse generator 50 , as required, to generate and deliver a cardioversion or defibrillation shock.", "In at least one embodiment, the control unit 54 acts as a therapy device control unit 54 ′.", "The therapy device control 54 ′ may be connected, for example, to the shock pulse generator 50 , to a right-ventricular stimulation unit 56 , and to a left-ventricular stimulation unit 64 .", "[0052] The control unit 54 , in at least one embodiment, may include a tachycardia identification unit 90 and a dislocation identification unit 92 .", "[0053] By way of one or more embodiments, the terminal for the right-ventricular tip electrode pole RV Tip, and the terminal for the right-ventricular ring electrode pole RV Ring, are each connected to both the right-ventricular stimulation unit 56 and to a right-ventricular sensing unit 58 .", "Both the right-ventricular stimulation unit 56 and the right-ventricular sensing unit 58 , in one or more embodiments, are each connected to the control unit 54 .", "[0054] According to at least one embodiment, the right-ventricular stimulation unit 56 , following a control signal of the control unit 54 , may generate a right-ventricular stimulation pulse and may deliver the right-ventricular stimulation pulse via the terminals for the right-ventricular ring electrode pole and the right-ventricular tip electrode pole.", "In one or more embodiments, the housing 42 of the heart stimulator 10 may form a neutral electrode, and the right-ventricular stimulation unit 56 may be connected to the terminal for the right-ventricular tip electrode pole RV Tip and to the housing 42 as another electrode to deliver a stimulation pulse.", "In at least one embodiment, the right-ventricular stimulation pulse differs from a defibrillation shock in that the stimulation pulse has a much lower pulse intensity, such that, by contrast to a defibrillation shock, it does not excite the entire heart tissue (myocardium) of a heart chamber in one attempt, but only excites the heart muscle cells in the direct vicinity of the right-ventricular tip electrode pole 18 .", "In one or more embodiments, the excitation then propagates further as a result of natural conduction over the entire ventricle and thus ensures a stimulated contraction of the ventricle.", "[0055] In at least one embodiment, the right-ventricular sensing unit 58 may first amplify, using an input amplifier, and then filter electric potentials applied across the terminal for the right-ventricular ring electrode pole RV Ring and the right-ventricular tip electrode pole RV Tip.", "By way of one or more embodiments, the right-ventricular sensing unit 58 may evaluate the course of the electric signals applied across its inputs in such a way that the right-ventricular sensing unit 58 automatically detects a natural (intrinsic) beat, such an as automatic contraction of the right ventricle.", "In at least one embodiment, the evaluation may be achieved, for example, by comparing the course of the signal applied across the inputs of the right-ventricular sensing unit 58 to a threshold value.", "In one or more embodiments, the largest amplitude of the signal is in the form of an R-spike, which is characteristic for a natural contraction of the right ventricle and which may be detected by comparison with a threshold value.", "In at least one embodiment, the right-ventricular sensing unit 58 , therefrom, may output a corresponding output signal (for example a marker signal), indicating a natural contraction of the right ventricle, to the control unit 54 , the tachycardia identification unit 90 and to the dislocation identification unit 92 thereof.", "[0056] In one or more embodiments, the terminal for the left-ventricular tip electrode pole LV Tip and the terminal for the left-ventricular ring electrode pole LV Ring are also connected to the left-ventricular stimulation unit 64 and a left-ventricular sensing unit 66 .", "In at least one embodiment, the left-ventricular stimulation unit 64 and the left-ventricular sensing unit 66 may be connected to the control unit 54 .", "In one or more embodiments, both the left-ventricular stimulation unit 64 and the left-ventricular sensing unit 66 may function similarly to the stimulation units 56 and 60 and sensing units 58 and 62 as described above.", "[0057] In at least one embodiment, the heart stimulator 10 may include an activity sensor 72 connected to the control unit 54 and generally includes timer 82 .", "The activity sensor 72 , in one or more embodiments, may detect a signal, for example a motion signal, dependent on the physical activity of a patient and may output a corresponding signal, indicating the physical activity of the patient, to the control unit 54 .", "As such, in at least one embodiment, the control unit 54 may adapt the timing of the stimulation pulse to the demand of the patient (hemodynamic demand).", "[0058] According to at least one embodiment, the heart stimulator 10 may include a memory unit 80 , connected to the control unit 54 , that stores signals generated or evaluated by the control unit 54 .", "In one or more embodiments, the memory unit 80 may store control programs for the control unit 54 in modifiable form.", "In at least one embodiment, the control unit 54 may be connected to a timer 82 .", "[0059] By way of one or more embodiments, the heart stimulator 10 may include at least one bidirectional telemetry interface 84 to transfer stored data from the implant 10 to an external device 100 and, vice versa, to also receive program settings and therapy commands from the external device 100 .", "[0060] FIG. 4 shows a biventricular three-chamber cardiac pacemaker and implantable cardioverter-defibrillator (ICD) as an implantable cardiac stimulator.", "As shown in FIG. 4 , the implantable cardiac stimulator 10 ′, in at least one embodiment, is connected via its terminal block 11 (header) to one or more of a right-ventricular electrode line 16 , a left-ventricular electrode line 30 , and a right-atrial electrode line 14 .", "[0061] In one or more embodiments, at least one of the electrode lines 16 , 30 and 14 , may be implanted permanently in the heart 12 .", "In at least one embodiment, the right-ventricular electrode line 16 has at the distal end a bipolar stimulation and sensing electrode with a tip electrode pole RV Tip 18 and a ring electrode pole RV Ring 20 .", "According to at least one embodiment, the electrode line 16 may include a distal shock coil RV Coil 38 and additionally a proximal shock coil SVC Coil 40 .", "The distal shock coil RV Coil 38 , in at least one embodiment, may be arranged such that it is located in the right ventricle 28 .", "The proximal shock coil SVC Coil 40 , in at least one embodiment, may be located in the upper part of the right atrium 26 or in the superior vena cava (precava).", "[0062] By way of one or more embodiments, the electrode line 14 is an atrial electrode line and may include at the distal end a bipolar stimulation and sensing electrode, formed by a tip electrode pole RA Tip 22 and a ring electrode pole RA Ring 24 .", "The electrode line 14 is implanted in the right atrium 26 .", "[0063] As shown in FIG. 4 , according to one or more embodiments, the left-ventricular electrode line 30 may include a left-ventricular shock coil 36 that delivers defibrillation shocks to the left ventricle.", "In at least one embodiment, the shock coil 36 may reach out from the left ventricle 44 as far as the left atrium 46 .", "In at least one embodiment, the implantable cardiac stimulator 10 ′ may include a second electrode, to deliver a shock, as the electrically active housing 42 of the implant 10 ′.", "[0064] As shown from FIG. 3 , in at least one embodiment of the invention, according to the components illustrated in a dotted manner, the terminal for the right-atrial tip electrode pole and the terminal for the right-atrial ring electrode pole may be connected both to a right-atrial stimulation unit 60 and to a right-atrial sensing unit 62 , which are each in turn connected to the control unit 54 .", "In one or more embodiments, the right-atrial stimulation unit 60 may generate stimulation pulses, of which the intensity is sufficient to excite the right-atrial myocardium.", "In at least one embodiment, the right-atrial stimulation pulses may have pulse intensity that is different from the right-ventricular stimulation pulses.", "The right-atrial sensing unit 62 , in at least one embodiment, may detect a P-wave from the course of the differential signal applied across the inputs thereof, wherein the P-wave represents a natural (intrinsic) contraction of the right atrium.", "If the right-atrial sensing unit 62 detects a corresponding P-wave, in at least one embodiment of the invention, it generates an output signal and forwards the output signal to the control unit 54 , wherein the output signal represents a natural contraction of the right atrium.", "[0065] As also shown in FIG. 3 , according to the components illustrated in a dotted manner, the left-ventricular shock coil 36 , as illustrated in FIG. 4 , may be connected to the shock pulse generator 50 via a terminal LV-COIL and an electrode selection unit 52 .", "Using the electrode selection unit 52 , in one or more embodiments, the control unit 54 may select two or more electrodes (including the conductive housing 42 ) via which a shock is delivered.", "[0066] According to the heart therapy devices illustrated in FIGS. 2 to 4 , according to at least one embodiment of the invention, the tachycardic ventricular dysrhythmias may be classified by the right-ventricular 16 and/or the left-ventricular electrode line 30 , primarily via the sensed heartbeats, wherein the frequency and frequency stability of both sides of the ventricle may be evaluated during therapy selection.", "If the frequencies of both ventricles differ significantly, in one or more embodiments, the slower rhythm is thus evaluated in terms of frequency and optionally stability.", "In at least one embodiment, an ATP is always delivered to the slower ventricle side, only if the ventricle side has a frequency below a programmable frequency limit, or if a stability is detected on the respective ventricle side.", "[0067] FIG. 5 shows an example of an induced dissimilar ventricular tachycardia.", "As shown in FIG. 5 , an unstable and very quick rhythm corresponding to a ventricular fibrillation is shown in the right-ventricular IEGM (RV), wherein a tachycardia with comparatively regular cycle length is shown in the left ventricle (LV).", "[0068] In at least one embodiment, a dissimilar tachycardia may be classified by conventional ICD systems as ventricular fibrillation (VF;", "see “RV”", "line) and may always initiate defibrillation shock therapy.", "[0069] According to one or more embodiments, a dysrhythmia may be treated successfully and painlessly using antitachycardia stimulation, if the ATP is applied to the slower, stable ventricle side.", "In at least one embodiment, an electrophysiological explanatory model may be based on a myocardial conduction and refractory period structure, for example in the left ventricle, wherein the right-ventricular structure may already demonstrate disassociated conduction and refractory period conditions.", "In one or more embodiments, as shown in FIG. 5 , if the left-hand VT is successfully terminated by an ATP, the dysrhythmia may also terminate on the right-hand side with a high level of probability.", "[0070] FIG. 6 shows a flow chart for therapy management in the event of dissimilar ventricular tachycardias, according to at least one embodiment of the invention.", "[0071] In one or more embodiments, when a tachycardia is identified, the therapy control unit may first check for a dissimilarity (RV≠LV).", "If the rhythm is dissimilar, in at least one embodiment, then the therapy control unit may check which ventricle frequency, of the left ventricle and the right ventricle, is slower (RV>LV).", "In one or more embodiments, for the slower side, the therapy control unit may check whether the frequency already lies within the VF-zone requiring a shock (RV/LV>VF).", "If the frequency does not already lie in the VF-zone requiring a shock, by way of at least one embodiment, an ATP is delivered to the respective ventricle side.", "In at least one embodiment, if the rhythm on the slower ventricle side is also already within the VF-zone, a shock ( ) may then be immediately delivered if the rhythm is unstable (RV/LV unstab.), otherwise an ATP attempt may be delivered on the respective side.", "As such, in one or more embodiments, the therapy control unit may start the charging process for a shock either thereafter, or during the ATP delivery (such as ATP one shot).", "[0072] FIG. 7 shows an example of successful termination of a dissimilar VT.", "As shown in FIG. 7 , the frequency of the left-ventricular tachycardia may be twice as high as that of the right-ventricular VT, may fall within the VF-zone, and may be treated by shock therapy.", "According to at least one embodiment of the invention, an ATP (*Burst), delivered to the slower ventricle side (for example shown as the RV in FIG. 7 ), may successfully terminate the ventricular tachycardia, and therefore delivery of a shock is not needed.", "[0073] FIG. 8 shows an example of an ATP in the event of identified regularization of a VF, according to at least one embodiment of the invention.", "As shown in FIG. 8 , according to operating principles of the heart therapy device 10 and 10 ′, the tachycardia identification unit 90 may continuously scan one or both ventricle channels after regularization of the rhythm during the charging of the one or more shock capacitors for defibrillation therapy.", "In one or more embodiments, the control unit 54 , in the event of regularization (for example stability criterion), may trigger an ATP attempt during the charging of the one or more shock capacitors in the respective ventricle channel.", "FIG. 8 shows an irregular ventricular fibrillation, wherein according to at least one embodiment, after detection, may lead to charging of the one or more shock capacitors.", "In one or more embodiments, while the one or more shock capacitors are being charged, the rhythm in both ventricles, the left ventricle and the right ventricle, are checked for regularization, and, in the event of identified regularization, an ATP attempt may be delivered in the ventricle channel first classified as being regular (shown as the RV in FIG. 8 ).", "As shown in FIG. 8 , according to at least one embodiment, the ATP is successful and shock delivery is therefore inhibited.", "[0074] In one or more embodiments, a stability criterion, optionally with a programmable upper frequency limit, may be used as a criterion for regularization.", "[0075] In at least one embodiment, using the stability criterion may reduce unnecessary shock deliveries, even in a single-chamber system.", "[0076] One or more embodiments of the invention enable optimization of the therapy efficiency of antitachycardia stimulation, such as in the case of dissimilar and quick ventricular dysrhythmias, and thus serve to reduce the unnecessary shock deliveries in ICD therapy.", "[0077] It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teaching.", "The disclosed examples and embodiments are presented for purposes of illustration only.", "Other alternate embodiments may include some or all of the features disclosed herein.", "Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention." ]
[0001] This application is a continuation-in-part (CIP) of U.S. patent application Ser. No. 10/100,494, filed on Mar. 18, 2002. CROSS-REFERENCE TO RELATED APPLICATIONS [0002] The present invention is related to those disclosed in the following U.S. Non-Provisional patent applications: [0003] 1) Ser. No. 10/038,878, filed Dec. 31, 2001, entitled “SYSTEM AND METHOD FOR DISTRIBUTED CALL PROCESSING USING LOAD SHARING GROUPS”; [0004] 2) Ser. No. 10/039,186, filed Dec. 31, 2001, entitled “SYSTEM AND METHOD FOR DISTRIBUTED CALL PROCESSING USING A DISTRIBUTED TRUNK IDLE LIST”; [0005] 3) Ser. No. 10/038,872, filed Dec. 31, 2001, entitled “DISTRIBUTED IDENTITY SERVER FOR USE IN A TELECOMMUNICATION SWITCH”; [0006] 4) Ser. No. 10/038,879, filed Dec. 31, 2001, entitled “SYSTEM AND METHOD FOR PROVIDING A SUBSCRIBER DATABASE USING GROUP SERVICES IN A TELECOMMUNICATION SYSTEM”; and [0007] 5) Ser. No. 10/100,494 filed on Mar. 18, 2002, entitled “SYSTEM AND METHOD FOR ON-LINE UPGRADE OF CALL PROCESSING SLOTWARE USING LOAD SHARING GROUPS.” [0008] The above applications are commonly assigned to the assignee of the present invention. The disclosures of these related patent applications are hereby incorporated by reference for all purposes as if fully set forth herein. TECHNICAL FIELD OF THE INVENTION [0009] The present invention is directed, in general, to any real time or near-real time transaction processing software in telecommunication systems and, more specifically, to a method for performing on-line upgrades of call processing software using group services. BACKGROUND OF THE INVENTION [0010] Telecommunication service providers continually try to create new markets and to expand existing markets for telecommunication services and equipment. One important way to accomplish this is to improve the performance of existing network equipment while making the equipment cheaper and more reliable. Doing this allows the service providers to reduce infrastructure and operating costs while maintaining or even increasing the capacity of their wireless networks. At the same time, the service providers are attempting to improve the quality of telecommunication services and increase the quantity of services available to the end-user. [0011] A conventional switching center typically contains a large switching fabric controlled by a main processing unit (MPU) that contains a large number of data processors and associated memories, often in the form of ASIC chips. Each of these MPU processors contains a call process client application for controlling the flow of control signals of a single call. Each call process client application in turn communicates with a call process server application that controls the flow of control signals for a large number of calls. [0012] Thus, when a particular event occurs during a phone call (e.g., the call set-up, the invocation of three-way calling, call disconnection, or the like), control signals associated with the event are relayed from the origination station to the call process client application in the switching center. This call processing client application then relays the control signals to the call process server application, which actually performs the call processing service requested by the control signals. [0013] Unfortunately, in large capacity systems, bottlenecks may develop around the call process server applications. Each call process client application must communicate with a particular piece of server hardware that is executing the call process server application. Due to the random nature of the start and stop of phone calls, in large systems, some servers may be near capacity and develop bottlenecks, while other servers still have plenty of adequate bandwidth. Moreover, a system failure in a particular piece of server hardware results in the loss of all call processes being handled by a call process server application being executed on the failed server. [0014] Moreover, upgrading the call process server applications in a conventional switching center without interrupting existing service is extremely complicated. In some prior art systems, performing a software upgrade requires fully redundant (duplex) hardware in the switching center. The redundant components are split into an active side and an inactive side. Complex control software is required to manage the split (by swapping active and inactive sides) and to manage the process of merging the two halves of the system back into a unitary system. The redundant hardware adds excessive cost to the prior art switching center and the complex control software is expensive to develop, susceptible to errors due to its complexity, and difficult to maintain. [0015] Therefore, there is a need for improved telecommunication network equipment and services. In particular, there is a need for switching centers that may easily undergo on-line software upgrades. More particularly, there is a need for switching centers that may be upgraded on-line without requiring the use of redundant hardware and without requiring complex and expensive control software. SUMMARY OF THE INVENTION [0016] To address the above-discussed deficiencies of the prior art, it is a primary object of the present invention to provide, for use in a switch comprising N call application nodes (CANs), a method of upgrading a plurality of call process server applications, wherein each of the call process server applications comprises a primary call process and a backup call process executed on different ones of the N CANs. According to an advantageous embodiment of the present invention, the method comprising the steps of: 1) receiving a shutdown command operable to upgrade a first call process server application comprising a first primary call process executed on a first CAN and a first backup call process executed on a second CAN; 2) in response to receipt of the shutdown command, disabling the first primary call process such that no future call traffic associated with the first call process server application is directed to the first primary call process on the first CAN; 3) re-designating the first backup call process as a new primary call process of the first call process server application such that all future call traffic associated with pre-existing calls handled by the first call process server application is directed to the re-designated first backup call process on the second CAN without the direct knowledge or involvement of the sending application;; 4) moving a second backup call process, if any, associated with a second call process server application and resident on the first CAN to a different CAN; and 5) installing an upgraded first call process server application on the first CAN, such that an upgraded first primary call process of the upgraded first call process server application executes on the first CAN and creates on the first CAN an upgraded first backup call process of the upgraded first call process server application. [0017] According to one embodiment of the present invention, the method comprises the further step of removing the disabled first primary call process from the first CAN. [0018] According to another embodiment of the present invention, the method comprises the further step of preventing future call traffic associated with new calls from being directed to the re-designated first backup call process. [0019] According to still another embodiment of the present invention, the method comprises the further step of removing the re-designated first backup call process from the second CAN when all pre-existing calls are terminated. [0020] According to yet another embodiment of the present invention, the upgraded first primary call process joins a first load sharing group server application comprising call process server applications similar to the upgraded first call process server application. [0021] According to a further embodiment of the present invention, the first load sharing group server application directs new call traffic associated with new calls to the upgraded first primary call process under control of a throttling mechanism. [0022] According to a still further embodiment of the present invention, the throttling mechanism initially causes relatively small amounts of new call traffic to be directed to the upgraded first primary call process. [0023] According to a yet further embodiment of the present invention, the throttling mechanism causes gradually increasing amounts of new call traffic to be directed to the upgraded first primary call process. [0024] The foregoing has outlined rather broadly the features and technical advantages of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they may readily use the conception and the specific embodiment disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form. [0025] Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. BRIEF DESCRIPTION OF THE DRAWINGS [0026] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, wherein like numbers designate like objects, and in which: [0027] [0027]FIG. 1 illustrates an exemplary wireless network according to one embodiment of the present invention; [0028] [0028]FIG. 2 illustrates an exemplary mobile switching center in greater detail according to one embodiment of the present invention; [0029] [0029]FIG. 3 illustrates selected portions of a mobile switching center that perform distributed call processing using group services according to the principles of the present invention; [0030] [0030]FIG. 4 is a flow diagram illustrating the partitioning and on-line upgrade of call process server applications in a mobile switching center according to the principles of the present invention; and [0031] FIGS. 5 A- 5 K are a sequence of views of the call application nodes in the exemplary mobile switching center (MSC) as the call application nodes undergo the partitioning and on-line upgrade process illustrated in FIG. 4. DETAILED DESCRIPTION OF THE INVENTION [0032] [0032]FIGS. 1 through 5, discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will understand that the principles of the present invention may be implemented in any suitably arranged telecommunications network. [0033] In the disclosure that follows, a group services framework for performing various distributed call processing functions is implemented in a mobile switching center of a wireless communication network. This is by way of illustration only and should not be construed so as to limit the scope of the invention. Those skilled in the art will understand that the group services framework described below may be implemented in other types of telecommunication network and devices, including many varieties of switches, routers and the like, and including entirely wireline networks that do not contain wireless devices. [0034] [0034]FIG. 1 illustrates exemplary wireless network 100 according to one embodiment of the present invention. Wireless network 100 comprises a plurality of cell sites 121 - 123 , each containing one of the base stations, BS 101 , BS 102 , or BS 103 . Base stations 101 - 103 communicate with a plurality of mobile stations (MS) 111 - 114 over, for example, code division multiple access (CDMA) channels. Mobile stations 111 - 114 may be any suitable wireless devices, including conventional cellular radiotelephones, PCS handset devices, personal digital assistants, portable computers, or metering devices. The present invention is not limited to mobile devices. Other types of access terminals, including fixed wireless terminals, may be used. However, for the sake of simplicity, only mobile stations are shown and discussed hereafter. [0035] Dotted lines show the approximate boundaries of the cell sites 121 - 123 in which base stations 101 - 103 are located. The cell sites are shown approximately circular for the purposes of illustration and explanation only. It should be clearly understood that the cell sites may have other irregular shapes, depending on the cell configuration selected and natural and man-made obstructions. [0036] As is well known in the art, cell sites 121 - 123 are comprised of a plurality of sectors (not shown), each sector being illuminated by a directional antenna coupled to the base station. The embodiment of FIG. 1 illustrates the base station in the center of the cell. Alternate embodiments position the directional antennas in corners of the sectors. The system of the present invention is not limited to any one cell site configuration. [0037] In one embodiment of the present invention, BS 101 , BS 102 , and BS 103 comprise a base station controller (BSC) and one or more base transceiver subsystem(s) (BTS). Base station controllers and base transceiver subsystems are well known to those skilled in the art. A base station controller is a device that manages wireless communications resources, including the base transceiver stations, for specified cells within a wireless communications network. A base transceiver subsystem comprises the RF transceivers, antennas, and other electrical equipment located in each cell site. This equipment may include air conditioning units, heating units, electrical supplies, telephone line interfaces, and RF transmitters and RF receivers. For the purpose of simplicity and clarity in explaining the operation of the present invention, the base transceiver subsystem in each of cells 121 , 122 , and 123 and the base station controller associated with each base transceiver subsystem are collectively represented by BS 101 , BS 102 and BS 103 , respectively. [0038] BS 101 , BS 102 and BS 103 transfer voice and data signals between each other and the public switched telephone network (PSTN) (not shown) via communication trunk lines 131 , mobile switching center (MSC) 140 , and communication trunk lines 132 . Trunk lines 131 also provide connection paths to transfer control signals between MSC 140 and BS 101 , BS 102 and BS 103 that are used to establish connections for voice and data circuits between MSC 140 and BS 101 , BS 102 and BS 103 over communication trunk lines 131 and between MSC 140 and the Internet or the PSTN over communication trunk lines 132 . In some embodiments of the present invention, communication trunk lines 131 may be several different data links, where each data link couples one of BS 101 , BS 102 , or BS 103 to MSC 140 . [0039] Trunk lines 131 and 132 comprise one or more of any suitable connection means, including a T1 line, a T3 line, a fiber optic link, a network packet data backbone connection, or any other type of data connection. Those skilled in the art will recognize that the connections on trunk lines 131 and 132 may provide a transmission path for transmission of analog voice band signals, a digital path for transmission of voice signals in the pulse code modulated (PCM) format, a digital path for transmission of voice signals in an Internet Protocol (IP) format, a digital path for transmission of voice signals in an asynchronous transfer mode (ATM) format, or other suitable connection transmission protocol. Those skilled in the art will recognize that the connections on trunk lines 131 and 132 may provide a transmission path for transmission of analog or digital control signals in a suitable signaling protocol. [0040] [0040]FIG. 2 illustrates exemplary mobile switching center 140 in greater detail according to one embodiment of the present invention. MSC 140 includes interconnecting network 200 , among other things. Interconnecting network 200 comprises switch fabric 205 and switch controller 210 , which together provide switch paths between communication circuits in trunk lines 131 and 132 . MSC 140 provides services and coordination between the subscribers in wireless network 100 and external networks, such as the PSTN or Internet. Mobile switching centers similar to MSC 140 are well known to those skilled in the art. [0041] When a wireless network subscriber turns on his or her mobile station (e.g., cell phone) or fixed access terminal, radio messages over the air interface inform the base station that the mobile station (or fixed access terminal) is joining the network. However, a connection is not automatically made to voice or data traffic carrying circuits in trunk lines 131 - 132 . A voice or data traffic connection to the public switched telephone network (PSTN) or the Internet is not needed until the subscriber places a call (e.g., dials a phone number) or accesses the Internet. [0042] However, even when the phone is idle, certain information about the subscriber (i.e., subscriber data) must be retrieved and stored in either the base station or in MSC 140 , or both, in order to authenticate the subscriber, gather billing information, identify the services available to the subscriber, determine capabilities of the mobile station, and the like. The control signals (as opposed to voice and data traffic) required to do this are also carried over trunk lines 131 and 132 . After the subscriber data is stored in memory in MSC 140 , it is available for use by a variety of call processing client (CPC) applications that may be initiated by the subscriber or another device while the mobile station is still active. [0043] For example, when MS 111 is first turned ON, a call process is set up in MSC 140 for MS 111 and subscriber data (e.g., billing information) is stored in MSC 140 that may be accessed by the call process or other call applications that provide particular types of call services. If the subscriber dials a phone number on MS 111 or a call is received from the PSTN directed to MS 111 , the call process for MS 111 handles the establishment of a call connection on one of the trunk lines in trunk line 131 and one of the trunk lines in trunk line 132 . The MS 111 call process executed in MSC 140 maintains all state information related to the call and to MS 111 and handles all other applications required by MS 111 , including three-way calls, voice mail, call disconnection, and the like. [0044] In order to handle a large amount of call traffic, it is necessary to distribute the many active call processes and call service applications handled by MSC 111 across a number of call application nodes. The call services may include application for accessing a subscriber database, selecting (or de-selecting) trunk, lines, retrieving and maintaining call identity information, and the like. The present invention provides methods and apparatuses for distributing call processes and call service applications across multiple call application nodes in a highly reliable and redundant manner. This is accomplished by a distributed network of redundant servers in which call traffic is distributed in order to increase the call-handling capacity of MSC 140 . The redundancy of the distributed servers is transparent to both the call process client applications that require a service and the call process server applications that provide the service. It also decreases the complexity of both the client and server applications. [0045] [0045]FIG. 3 illustrates in greater detail selected portions of exemplary mobile switching center 140 that perform distributed call processing using group services in accordance with the principles of the present invention. MSC 140 comprises main processing unit (MPU) 310 , system manager node 1 (SYSMGR 1 ), optional system manager node 2 (SYSMGR 2 ), and master database 320 . MSC 140 also comprises a plurality of call application nodes (CANs), including CAN 1 , CAN 2 , and CAN 3 , and a plurality of local storage devices (SDs), namely SD 1 , SD 2 , and SD 3 , that are associated with CAN 1 , CAN 2 and CAN 3 . Master database 320 may be used as a master software repository to store databases, software images, server statistics, log-in data, and the like. SD 1 -SD 3 may be used to store local capsules, transient data, and the like. [0046] The system manager nodes 1 and 2 , collectively, and CAN 1 -CAN 3 execute a configuration management (CM) process that sets up each node with the appropriate software and configuration data upon initial start-up or after a reboot. Every node in the system also executes a node monitor (NM) process that loads software and tracks processes to determine if any process has failed. System manager nodes 1 and 2 execute a first arbitrary process, P 1 , and system manager node 1 also executes a second arbitrary process, P 2 . [0047] In accordance with the principles of the present invention, call application nodes 1 - 3 (CAN 1 -CAN 3 ) execute a number of call process (CP) server applications organized as primary and backup processes that are available as distributed group services to 1 to N call process client (CPC) applications, namely CPC APP 1 -CPC APPn in main processing unit 310 . The N call application nodes (e.g., CAN 1 -CAN 3 ) are separate computing nodes comprising a processor and memory that provide scalability and redundancy by the simple addition of more call application nodes. [0048] Each of the N call process client (CPC) applications, namely CPC APP 1 -CPC APPn in MPU 310 handles the control signals and messages related to a single call associated with a mobile station. Each of CPC APP 1 -CPC APPn establishes a session with a load sharing group, which assigns the call to a particular one of the primary-backup group call process server applications, CP 1 , CP 2 , or CP 3 . The selected call process server application actually performs the call process services/functions requested by the call process client application. [0049] In the illustrated embodiment, three exemplary call process server applications are being executed, namely CP 1 , CP 2 , and CP 3 . Each of these processes exists as a primary-backup group. Thus, CP 1 exists as a primary process, CP 1 (P), and a backup process, CP 1 (B). Similarly, CP 2 exists as a primary process, CP 2 (P), and a backup process, CP 2 (B), and CP 3 exists as a primary process, CP 3 (P), and a backup process, CP 3 (B). In the illustrated embodiment, CP 1 (P) and CP 1 (B) reside on different call application nodes (i.e., CAN 1 and CAN 2 ). This is not a strict requirement: CP 1 (P) and CP 1 (B) may reside on the same call application node (e.g., CAN 1 ) and still provide reliability and redundancy for software failures of the primary process, CP 1 (P). However, in a preferred embodiment of the present invention, the primary process and the backup process reside on different call application nodes, thereby providing hardware redundancy as well as software redundancy. Thus, CP 1 (P) and CP 1 (B) reside on CAN 1 and CAN 2 , CP 2 (P) and CP 2 (B) reside on CAN 2 and CAN 3 , and CP 3 (P) and CP 3 (B) reside on CAN 3 and CAN 1 . [0050] Together, CP 1 , CP 2 and CP 3 form a supergroup for load sharing purposes. Thus, CP 1 (P) and CP 1 (B), CP 2 (P) and CP 2 (B), and CP 3 (P) and CP 3 (B) are part of a first load sharing group (LSG 1 ), indicated by the dotted line boundary. Additionally, CAN 1 -CAN 3 host three other load sharing groups, namely, LSG 2 , LSG 3 , and LSG 4 . LSG 2 comprises two trunk idle list (TIL) server applications, namely TIL 1 and TIL 2 . TIL 1 exists as a primary process, TIL 1 (P), on CAN 2 and a backup process, TIL 1 (B), on CAN 3 . TIL 2 exists as a primary process, TIL 2 (P), on CAN 3 and a backup process, TIL 2 (B), on CAN 2 . Similarly, LSG 3 comprises two identity server (IS) applications, namely IS 1 and IS 2 . IS 1 exists as a primary process, IS 1 (P), on CAN 1 and a backup process, IS 1 (B), on CAN 2 and IS 2 exists as a primary process, IS 2 (P), on CAN 2 and a backup process, IS 2 (B), on CAN 1 . Finally, LSG 4 comprises two subscriber database (SDB) server applications, namely SDB 1 and SDB 2 . SDB 1 exists as a primary process, SDB 1 (P), on CAN 2 and a backup process, SDB 1 (B), on CAN 3 and SDB 2 exists as a primary process, SDB 2 (P), on CAN 3 and a backup process, SDB 2 (B), on CAN 2 . [0051] A group service provides a framework for organizing a group of distributed software objects in a computing network. Each software object provides a service. In addition, the group service framework provides enhanced behavior for determining group membership, deciding what actions to take in the presence of faults, and controlling unicast, multicast, and groupcast communications between members and clients for the group. A group utilizes a policy to enhance the behavior of the services provided by the group. Some of these policies include primary-backup for high service availability and load sharing for distributing the loading of services within a network. [0052] Call process server applications, such as CP 1 -CP 3 , IS 1 -IS 2 , and TIL 1 -TIL 2 , located within a computing network provide services that are invoked by client applications, such as CPC APP 1 -CPC APPn. As shown in FIG. 3, the call process server applications are organized into primary-backup groups configured as a 1+1 type of primary-backup group. There are multiple numbers of these primary-backup groups and the exact number is scalable according to the number of processes and/or computing nodes (CANs) that are used. All of the primary-backup groups are themselves a member of a single load sharing group (e.g., LSG 1 , LSG 2 , LSG 3 , LSG 4 ). [0053] It is important to note that while the call process client applications, CPC APP 1 -CPC APPn, are clients with respect to the call process server applications, CP 1 , CP 2 , and CP 3 , a server application may be a client with respect to another server application. In particular, the call process server applications CP 1 -CP 3 may be clients with respect to the trunk idle list server applications, TIL 1 and TIL 2 , the subscriber database server applications, SDB 1 and SDB 2 , and the identity server applications, IS 1 and IS 2 . [0054] A client application establishes an interface to the load sharing group. When a new call indication is received by the client application, the client application establishes a session with the load sharing group according to a client-side load sharing policy. The initial server (CP 1 , CP 2 , etc.) selection policy is CPU utilization-based (i.e., based on the processor load in each of the candidate CANs, with more lightly loaded groups selected first), but other algorithmic policies, such as round-robin (i.e., distribution of new calls in sequential order to each CAN) may be used. [0055] The client application associates the session with the new call and sends messages associated with the call over the session object. The client application also receives messages from the primary-backup group via the session established with the primary-backup group. Only the primary process (e.g., CP 1 (P)) of the primary-backup group joins the load sharing group (e.g., LSG 1 ). [0056] For a variety of reasons, the application containing the primary may be removed from service. With the removal of the primary member, the backup member becomes the primary and the server application is no longer a member of the load sharing group. However, the client application(s) still maintain their session with the primary-backup group for existing calls. New calls are not distributed to the primary-backup group if it is not a member of the load sharing group. [0057] If the primary of the primary-backup group that is a member of the load sharing group should fail, the backup member is informed that the primary member has failed (or left) and then assumes the role of primary member. The responsibility for these actions must be performed by the server application. It is the responsibility of the Group Service to inform the backup member that the primary member has failed or left. [0058] As part of an online software upgrade process, one or more applications containing primary-backup groups may be removed from service, brought down, and then brought back up using a new version of software code. These groups, if their interface has not changed, join the existing load sharing group. When first started, it is required that the client interface be capable of throttling the call traffic to specific primary-backup groups. The traffic throttling is expressed as a percentage varying from 0% (no calls) to 100%. All new calls that would have been scheduled according to the scheduling algorithm are handled by this session. The throttling factor is initialized to 100% for any primary-backup group that joins the load sharing group. During on-line software upgrades, the throttling factor is adjusted to start with the no-calls case for the new software version. Any client application for the load sharing group may establish a session with a specific primary-backup group. The client may then change the throttling factor at any time. When the throttling factor is changed, all client session interfaces receive via multicast the changed throttling factor. As the throttling factor is increased, the call process server applications with the new software version may receive increasing amounts of call traffic. [0059] Call processing communications from the client applications to the call processing server primary-backup groups must support a very high volume of calls. The group software utilizes an internal transport consisting of a multicasting protocol (simple IP multicast) and optionally a unicasting protocol. The unicasting protocol may be TCP/IP, SCTP, or other transport protocol. The multicast protocol is used for internal member communications relating to membership, state changes, and fault detection. In the absence of unicast transport, the multicast protocol is used for client/server communication streams. The unicast protocol, when provided, is used to provide a high-speed stream between clients and servers. The stream is always directed to the primary of a primary-backup group, which is transparent to both the call processing client application and the call process (e.g., CP 1 , CP 2 , CP 3 , TIL 1 , TIL 2 , IS 1 , IS 2 ). [0060] AS noted above, the call processes on the call application nodes (CANs) are organized into a load sharing group. Each call process (e.g., CP 1 , CP 2 , CP 3 , TIL 1 , TIL 2 , IS 1 , IS 2 ) is itself a primary-backup group. Both members of the primary-backup group may provide the service but only the primary of the group receives messages and thus actually provides the service. When a member of the group is selected as the primary, it registers one or more interface streams for the group. Each stream is a separate interface for some call processing service. [0061] The call processing client application (e.g., CPC APP 1 , CPC APP 2 ) in MSC 140 receives a new call indication and uses the group service to select an interface with a call application node (i.e., server) to handle the new call. The call process on each server (CAN) is a member of a load sharing group and a particular call application node (CAN) is selected on a CPU utilization (i.e., load) basis or other algorithmic basis (such as round-robin) from the perspective of the call process client application. For the particular primary-backup group that is selected a session is returned to the call processing client application. When the session is established with the primary-backup call process server group, the call processing client application then opens an interface to a particular member (representing an interface to a primary-backup group) and obtains a session interface. Each call processing server sends a message related to the new call over the session interface. Any subsequent transactions associated with the call are sent over the same session object. [0062] The call process server (i.e., primary-backup group) may asynchronously send messages over the session using one or more of the defined stream interfaces. The primary member of the call processing server group receives the transactions. The backup group member does not receive transactions. The primary group member sends updates to the backup group member. In an exemplary embodiment of the present invention, the primary group member decides when updates are sent to the backup group member. The primary starts sending updates when a call has been answered. Prior to the call being answered, the call is defined as being a transient call. After the call has been answered, the call is defined as being a stable call. The present invention protects stable calls from failures, but not transient calls. However, earlier and more frequent updates from the primary to the backup could also protect transient calls from failures. [0063] If the primary group member should fail, then the backup group member becomes the new primary member. According to the exemplary embodiment of the present invention, all transient call information during the fail-over period (the time between when the primary fails and the backup is changed to be the new primary) can be lost, but all stable call information is maintained by the backup. [0064] Advantageously, the present invention has no limitations on the scalability of the system and the system size is hidden from both and the primary-backup group server applications and call process client applications. The present invention eliminates any single point of failure in the system. Any failure within the system will not affect the system availability and performance. [0065] New call application nodes (CANs) and additional primary-backup group server applications (e.g., CP 1 , CP 2 , CP 3 , TIL 1 , TIL 2 , IS 1 , IS 2 ) may be added dynamically to the load sharing groups and can start servicing new call traffic. Call process client applications are not affected by the additions of new servers. If a server should fail, its backup assumes responsibility for the load. This provides high availability for the servicing of each call and minimizes dropped calls. [0066] Advantageously, the redundant architecture of call application nodes 1 - 3 (i.e., CAN 1 -CAN 3 ) and the use of primary-backup group server applications in mobile switching center 140 provides for a unique method for upgrading the call process server applications in MSC 140 without interrupting existing service. According to the principles of the present invention, each primary-backup group server application on each of CAN 1 -CAN 3 may be gracefully shutdown in order to effect a partitioning of a target call application node. The target call application node may then be upgraded to new primary-backup group server application software and the upgraded software may gradually be brought on-line and joined to load sharing groups using a throttling mechanism. Once the upgraded software is tested and fully operational, the process is continually repeated at the next targeted call application node until all call application nodes have been upgraded. [0067] [0067]FIG. 4 depicts flow diagram 400 , which illustrates the partitioning and on-line upgrade of primary-backup group server applications in mobile switching center 140 in accordance with the principles of the present invention. Initially, system manager node 1 may automatically (or maintenance personnel may manually) designate a first target call application node (e.g., CAN 1 ) to be upgraded (process step 405 ). Each primary call process Cpx(P) of a primary-backup group call process server application on the first target call application node is disabled and the corresponding backup call process CPx(B) on a different call application node (e.g., CAN 2 ) becomes the new primary call process. At this point, the new primary call process runs without a backup process. However, no call new traffic is sent to the new primary call process. Thus, the CPx primary-backup group eventually shuts down as existing calls disconnect (process step 410 ). [0068] Since the first target call application node may host one or more backup call processes related to primary call processes executed on other call application nodes, the present invention next moves all backup call processes CPy(B) on the first target call application node to different call application nodes (process step 415 ). The first target call application node is now free of all primary and backup call processes. The first target call application node is now a new partition and the remaining call applications are part of the old partition. [0069] Next, the upgraded software for the primary call process CPx(P)* is installed and the backup call process CPx(B)* is created in the first target call application node. This new primary-backup group call process server application then joins the appropriate load sharing group (i.e., LSG 1 ). At this point, the new primary server application is receiving no traffic. Thereafter, increasing amounts of new call traffic are sent to the upgraded primary call process Cpx(P)* using a throttling mechanism controlled by the craftsperson (or algorithmically by the system manager) until upgraded primary-backup group Cpx* operates at 100% (process step 420 ). [0070] Thereafter, steps 405 , 410 , 415 , 420 are repeated for a second target call application node (e.g., CAN 2 ) so that an upgraded primary call process CPz(P)* and an upgraded backup call process CPz(B)* are installed (or created) and operating on the second target call application node (process step 425 ). The second call target call application node is now part of the new partition, along with the first target call application node. [0071] Finally, the managing software application swaps the locations of the backup call processes CPx(B)* and Cpz(B)* so that the primary and backup call processes are not running on the same call application nodes (process step 430 ). The upgrade process then continues on to other call application nodes until all remaining call application nodes have joined the new partition and the old partition (containing the old software) ceases to exist. [0072] FIGS. 5 A- 5 K are a sequence of views of the call application nodes in exemplary mobile switching center (MSC) 140 as the call application nodes undergo the partitioning and on-line upgrade process illustrated in FIG. 4. [0073] [0073]FIG. 5A illustrates the initial view of CAN 1 -CAN 3 in mobile switching center 140 . [0074] In FIG. 5B, primary call process CP 1 (P) in CAN 1 has be terminated and the related backup call process CP 1 (B) in CAN 2 has become the new primary call process CP 1 (P). No new traffic is directed to CP 1 (P) in CAN 2 . Also, the backup call process CP 3 (B) has been moved to CAN 2 . [0075] In FIG. 5C, new updated primary call process CP 1 (P)* has been installed in CAN 1 and new updated backup call process CP 1 (B)* has been created in CAN 1 . New call traffic can now be directed to primary call process CP 1 (P)* in increasing increments until new updated primary-backup group call process server application CP 1 * is fully functional. [0076] In FIG. 5D, the old call process CP 1 (P) in CAN 2 has finally shut down through termination of all existing calls. [0077] In FIG. 5E, primary call process CP 2 (P) in CAN 2 has be terminated and the related backup call process CP 2 (B) in CAN 3 has become the new primary call process CP 2 (P). No new traffic is directed to CP 2 (P) in CAN 3 . Also, the backup call process CP 3 (B) has been moved to CAN 3 . [0078] In FIG. 5F, new updated primary call process CP 2 (P)* has been installed in CAN 2 and new updated backup call process CP 2 (B)* has been created in CAN 2 . New call traffic can now be directed to primary call process CP 2 (P)* in increasing increments until new updated primary-backup group call process server application CP 2 * is fully functional. [0079] In FIG. 5G, the old call process CP 2 (P) in CAN 3 has finally shut down through termination of all existing calls. [0080] In FIG. 5H, the backup call processes CP 1 (B)* and CP 2 (B)* switch locations in CAN 1 and CAN 2 . [0081] In FIG. 5I, primary call process CP 3 (P) in CAN 3 has been starved for new calls by leaving the load sharing group. The primary call process CP 3 (P) and its associated backup process CP 3 (B) have been terminated after all existing call traffic ended. [0082] In FIG. 5J, new updated primary call process CP 3 (P)* has been installed in CAN 3 and new updated backup call process CP 3 (B)* has been created in CAN 3 . New call traffic can now be directed to primary call process CP 3 (P)* in increasing increments until new updated primary-backup group call process server application CP 3 * is fully functional. [0083] In FIG. 5K, the locations of backup call processes CP 1 (B)*, CP 2 (B)*, and CP 3 (B)* have been rotated in CAN 1 , CAN 2 , and CAN 3 to achieve the original configuration illustrated in FIG. 5A. [0084] Although the present invention has been described in detail, those skilled in the art should understand that they may make various changes, substitutions and alterations herein without departing from the spirit and scope of the invention in its broadest form.
For use in a switch comprising N call application nodes (CANs), a method of upgrading call process server applications that comprise a primary call process and a backup call process executed on different CANs. The method comprises the steps of: 1) receiving a shutdown command to shutdown a first call process server application comprising a first primary call process executed on a first CAN and a first backup call process executed on a second CAN; 2) disabling the first primary call process such that no future call traffic associated with the first call process server application is directed to the first primary call process; 3) re-designating the first backup call process as the new primary call process of the first call process server application such that all future call traffic associated with pre-existing calls handled by the first call process server application is directed to the re-designated first backup call process; 4) moving a second backup call process, if any, associated with a second call process server application and resident on the first CAN to a different CAN; and 5) installing an upgraded first call process server application on the first CAN, such that an upgraded first primary call process of the upgraded first call process server application executes on the first CAN and creates on the first CAN an upgraded first backup call process.
Condense the core contents of the given document.
[ "[0001] This application is a continuation-in-part (CIP) of U.S. patent application Ser.", "No. 10/100,494, filed on Mar. 18, 2002.", "CROSS-REFERENCE TO RELATED APPLICATIONS [0002] The present invention is related to those disclosed in the following U.S. Non-Provisional patent applications: [0003] 1) Ser.", "No. 10/038,878, filed Dec. 31, 2001, entitled “SYSTEM AND METHOD FOR DISTRIBUTED CALL PROCESSING USING LOAD SHARING GROUPS”;", "[0004] 2) Ser.", "No. 10/039,186, filed Dec. 31, 2001, entitled “SYSTEM AND METHOD FOR DISTRIBUTED CALL PROCESSING USING A DISTRIBUTED TRUNK IDLE LIST”;", "[0005] 3) Ser.", "No. 10/038,872, filed Dec. 31, 2001, entitled “DISTRIBUTED IDENTITY SERVER FOR USE IN A TELECOMMUNICATION SWITCH”;", "[0006] 4) Ser.", "No. 10/038,879, filed Dec. 31, 2001, entitled “SYSTEM AND METHOD FOR PROVIDING A SUBSCRIBER DATABASE USING GROUP SERVICES IN A TELECOMMUNICATION SYSTEM”;", "and [0007] 5) Ser.", "No. 10/100,494 filed on Mar. 18, 2002, entitled “SYSTEM AND METHOD FOR ON-LINE UPGRADE OF CALL PROCESSING SLOTWARE USING LOAD SHARING GROUPS.”", "[0008] The above applications are commonly assigned to the assignee of the present invention.", "The disclosures of these related patent applications are hereby incorporated by reference for all purposes as if fully set forth herein.", "TECHNICAL FIELD OF THE INVENTION [0009] The present invention is directed, in general, to any real time or near-real time transaction processing software in telecommunication systems and, more specifically, to a method for performing on-line upgrades of call processing software using group services.", "BACKGROUND OF THE INVENTION [0010] Telecommunication service providers continually try to create new markets and to expand existing markets for telecommunication services and equipment.", "One important way to accomplish this is to improve the performance of existing network equipment while making the equipment cheaper and more reliable.", "Doing this allows the service providers to reduce infrastructure and operating costs while maintaining or even increasing the capacity of their wireless networks.", "At the same time, the service providers are attempting to improve the quality of telecommunication services and increase the quantity of services available to the end-user.", "[0011] A conventional switching center typically contains a large switching fabric controlled by a main processing unit (MPU) that contains a large number of data processors and associated memories, often in the form of ASIC chips.", "Each of these MPU processors contains a call process client application for controlling the flow of control signals of a single call.", "Each call process client application in turn communicates with a call process server application that controls the flow of control signals for a large number of calls.", "[0012] Thus, when a particular event occurs during a phone call (e.g., the call set-up, the invocation of three-way calling, call disconnection, or the like), control signals associated with the event are relayed from the origination station to the call process client application in the switching center.", "This call processing client application then relays the control signals to the call process server application, which actually performs the call processing service requested by the control signals.", "[0013] Unfortunately, in large capacity systems, bottlenecks may develop around the call process server applications.", "Each call process client application must communicate with a particular piece of server hardware that is executing the call process server application.", "Due to the random nature of the start and stop of phone calls, in large systems, some servers may be near capacity and develop bottlenecks, while other servers still have plenty of adequate bandwidth.", "Moreover, a system failure in a particular piece of server hardware results in the loss of all call processes being handled by a call process server application being executed on the failed server.", "[0014] Moreover, upgrading the call process server applications in a conventional switching center without interrupting existing service is extremely complicated.", "In some prior art systems, performing a software upgrade requires fully redundant (duplex) hardware in the switching center.", "The redundant components are split into an active side and an inactive side.", "Complex control software is required to manage the split (by swapping active and inactive sides) and to manage the process of merging the two halves of the system back into a unitary system.", "The redundant hardware adds excessive cost to the prior art switching center and the complex control software is expensive to develop, susceptible to errors due to its complexity, and difficult to maintain.", "[0015] Therefore, there is a need for improved telecommunication network equipment and services.", "In particular, there is a need for switching centers that may easily undergo on-line software upgrades.", "More particularly, there is a need for switching centers that may be upgraded on-line without requiring the use of redundant hardware and without requiring complex and expensive control software.", "SUMMARY OF THE INVENTION [0016] To address the above-discussed deficiencies of the prior art, it is a primary object of the present invention to provide, for use in a switch comprising N call application nodes (CANs), a method of upgrading a plurality of call process server applications, wherein each of the call process server applications comprises a primary call process and a backup call process executed on different ones of the N CANs.", "According to an advantageous embodiment of the present invention, the method comprising the steps of: 1) receiving a shutdown command operable to upgrade a first call process server application comprising a first primary call process executed on a first CAN and a first backup call process executed on a second CAN;", "2) in response to receipt of the shutdown command, disabling the first primary call process such that no future call traffic associated with the first call process server application is directed to the first primary call process on the first CAN;", "3) re-designating the first backup call process as a new primary call process of the first call process server application such that all future call traffic associated with pre-existing calls handled by the first call process server application is directed to the re-designated first backup call process on the second CAN without the direct knowledge or involvement of the sending application;;", "4) moving a second backup call process, if any, associated with a second call process server application and resident on the first CAN to a different CAN;", "and 5) installing an upgraded first call process server application on the first CAN, such that an upgraded first primary call process of the upgraded first call process server application executes on the first CAN and creates on the first CAN an upgraded first backup call process of the upgraded first call process server application.", "[0017] According to one embodiment of the present invention, the method comprises the further step of removing the disabled first primary call process from the first CAN.", "[0018] According to another embodiment of the present invention, the method comprises the further step of preventing future call traffic associated with new calls from being directed to the re-designated first backup call process.", "[0019] According to still another embodiment of the present invention, the method comprises the further step of removing the re-designated first backup call process from the second CAN when all pre-existing calls are terminated.", "[0020] According to yet another embodiment of the present invention, the upgraded first primary call process joins a first load sharing group server application comprising call process server applications similar to the upgraded first call process server application.", "[0021] According to a further embodiment of the present invention, the first load sharing group server application directs new call traffic associated with new calls to the upgraded first primary call process under control of a throttling mechanism.", "[0022] According to a still further embodiment of the present invention, the throttling mechanism initially causes relatively small amounts of new call traffic to be directed to the upgraded first primary call process.", "[0023] According to a yet further embodiment of the present invention, the throttling mechanism causes gradually increasing amounts of new call traffic to be directed to the upgraded first primary call process.", "[0024] The foregoing has outlined rather broadly the features and technical advantages of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows.", "Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention.", "Those skilled in the art should appreciate that they may readily use the conception and the specific embodiment disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present invention.", "Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form.", "[0025] Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include”", "and “comprise,” as well as derivatives thereof, mean inclusion without limitation;", "the term “or,” is inclusive, meaning and/or;", "the phrases “associated with”", "and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like;", "and the term “controller”", "means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same.", "It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely.", "Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.", "BRIEF DESCRIPTION OF THE DRAWINGS [0026] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, wherein like numbers designate like objects, and in which: [0027] [0027 ]FIG. 1 illustrates an exemplary wireless network according to one embodiment of the present invention;", "[0028] [0028 ]FIG. 2 illustrates an exemplary mobile switching center in greater detail according to one embodiment of the present invention;", "[0029] [0029 ]FIG. 3 illustrates selected portions of a mobile switching center that perform distributed call processing using group services according to the principles of the present invention;", "[0030] [0030 ]FIG. 4 is a flow diagram illustrating the partitioning and on-line upgrade of call process server applications in a mobile switching center according to the principles of the present invention;", "and [0031] FIGS. 5 A- 5 K are a sequence of views of the call application nodes in the exemplary mobile switching center (MSC) as the call application nodes undergo the partitioning and on-line upgrade process illustrated in FIG. 4. DETAILED DESCRIPTION OF THE INVENTION [0032] [0032 ]FIGS. 1 through 5, discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention.", "Those skilled in the art will understand that the principles of the present invention may be implemented in any suitably arranged telecommunications network.", "[0033] In the disclosure that follows, a group services framework for performing various distributed call processing functions is implemented in a mobile switching center of a wireless communication network.", "This is by way of illustration only and should not be construed so as to limit the scope of the invention.", "Those skilled in the art will understand that the group services framework described below may be implemented in other types of telecommunication network and devices, including many varieties of switches, routers and the like, and including entirely wireline networks that do not contain wireless devices.", "[0034] [0034 ]FIG. 1 illustrates exemplary wireless network 100 according to one embodiment of the present invention.", "Wireless network 100 comprises a plurality of cell sites 121 - 123 , each containing one of the base stations, BS 101 , BS 102 , or BS 103 .", "Base stations 101 - 103 communicate with a plurality of mobile stations (MS) 111 - 114 over, for example, code division multiple access (CDMA) channels.", "Mobile stations 111 - 114 may be any suitable wireless devices, including conventional cellular radiotelephones, PCS handset devices, personal digital assistants, portable computers, or metering devices.", "The present invention is not limited to mobile devices.", "Other types of access terminals, including fixed wireless terminals, may be used.", "However, for the sake of simplicity, only mobile stations are shown and discussed hereafter.", "[0035] Dotted lines show the approximate boundaries of the cell sites 121 - 123 in which base stations 101 - 103 are located.", "The cell sites are shown approximately circular for the purposes of illustration and explanation only.", "It should be clearly understood that the cell sites may have other irregular shapes, depending on the cell configuration selected and natural and man-made obstructions.", "[0036] As is well known in the art, cell sites 121 - 123 are comprised of a plurality of sectors (not shown), each sector being illuminated by a directional antenna coupled to the base station.", "The embodiment of FIG. 1 illustrates the base station in the center of the cell.", "Alternate embodiments position the directional antennas in corners of the sectors.", "The system of the present invention is not limited to any one cell site configuration.", "[0037] In one embodiment of the present invention, BS 101 , BS 102 , and BS 103 comprise a base station controller (BSC) and one or more base transceiver subsystem(s) (BTS).", "Base station controllers and base transceiver subsystems are well known to those skilled in the art.", "A base station controller is a device that manages wireless communications resources, including the base transceiver stations, for specified cells within a wireless communications network.", "A base transceiver subsystem comprises the RF transceivers, antennas, and other electrical equipment located in each cell site.", "This equipment may include air conditioning units, heating units, electrical supplies, telephone line interfaces, and RF transmitters and RF receivers.", "For the purpose of simplicity and clarity in explaining the operation of the present invention, the base transceiver subsystem in each of cells 121 , 122 , and 123 and the base station controller associated with each base transceiver subsystem are collectively represented by BS 101 , BS 102 and BS 103 , respectively.", "[0038] BS 101 , BS 102 and BS 103 transfer voice and data signals between each other and the public switched telephone network (PSTN) (not shown) via communication trunk lines 131 , mobile switching center (MSC) 140 , and communication trunk lines 132 .", "Trunk lines 131 also provide connection paths to transfer control signals between MSC 140 and BS 101 , BS 102 and BS 103 that are used to establish connections for voice and data circuits between MSC 140 and BS 101 , BS 102 and BS 103 over communication trunk lines 131 and between MSC 140 and the Internet or the PSTN over communication trunk lines 132 .", "In some embodiments of the present invention, communication trunk lines 131 may be several different data links, where each data link couples one of BS 101 , BS 102 , or BS 103 to MSC 140 .", "[0039] Trunk lines 131 and 132 comprise one or more of any suitable connection means, including a T1 line, a T3 line, a fiber optic link, a network packet data backbone connection, or any other type of data connection.", "Those skilled in the art will recognize that the connections on trunk lines 131 and 132 may provide a transmission path for transmission of analog voice band signals, a digital path for transmission of voice signals in the pulse code modulated (PCM) format, a digital path for transmission of voice signals in an Internet Protocol (IP) format, a digital path for transmission of voice signals in an asynchronous transfer mode (ATM) format, or other suitable connection transmission protocol.", "Those skilled in the art will recognize that the connections on trunk lines 131 and 132 may provide a transmission path for transmission of analog or digital control signals in a suitable signaling protocol.", "[0040] [0040 ]FIG. 2 illustrates exemplary mobile switching center 140 in greater detail according to one embodiment of the present invention.", "MSC 140 includes interconnecting network 200 , among other things.", "Interconnecting network 200 comprises switch fabric 205 and switch controller 210 , which together provide switch paths between communication circuits in trunk lines 131 and 132 .", "MSC 140 provides services and coordination between the subscribers in wireless network 100 and external networks, such as the PSTN or Internet.", "Mobile switching centers similar to MSC 140 are well known to those skilled in the art.", "[0041] When a wireless network subscriber turns on his or her mobile station (e.g., cell phone) or fixed access terminal, radio messages over the air interface inform the base station that the mobile station (or fixed access terminal) is joining the network.", "However, a connection is not automatically made to voice or data traffic carrying circuits in trunk lines 131 - 132 .", "A voice or data traffic connection to the public switched telephone network (PSTN) or the Internet is not needed until the subscriber places a call (e.g., dials a phone number) or accesses the Internet.", "[0042] However, even when the phone is idle, certain information about the subscriber (i.e., subscriber data) must be retrieved and stored in either the base station or in MSC 140 , or both, in order to authenticate the subscriber, gather billing information, identify the services available to the subscriber, determine capabilities of the mobile station, and the like.", "The control signals (as opposed to voice and data traffic) required to do this are also carried over trunk lines 131 and 132 .", "After the subscriber data is stored in memory in MSC 140 , it is available for use by a variety of call processing client (CPC) applications that may be initiated by the subscriber or another device while the mobile station is still active.", "[0043] For example, when MS 111 is first turned ON, a call process is set up in MSC 140 for MS 111 and subscriber data (e.g., billing information) is stored in MSC 140 that may be accessed by the call process or other call applications that provide particular types of call services.", "If the subscriber dials a phone number on MS 111 or a call is received from the PSTN directed to MS 111 , the call process for MS 111 handles the establishment of a call connection on one of the trunk lines in trunk line 131 and one of the trunk lines in trunk line 132 .", "The MS 111 call process executed in MSC 140 maintains all state information related to the call and to MS 111 and handles all other applications required by MS 111 , including three-way calls, voice mail, call disconnection, and the like.", "[0044] In order to handle a large amount of call traffic, it is necessary to distribute the many active call processes and call service applications handled by MSC 111 across a number of call application nodes.", "The call services may include application for accessing a subscriber database, selecting (or de-selecting) trunk, lines, retrieving and maintaining call identity information, and the like.", "The present invention provides methods and apparatuses for distributing call processes and call service applications across multiple call application nodes in a highly reliable and redundant manner.", "This is accomplished by a distributed network of redundant servers in which call traffic is distributed in order to increase the call-handling capacity of MSC 140 .", "The redundancy of the distributed servers is transparent to both the call process client applications that require a service and the call process server applications that provide the service.", "It also decreases the complexity of both the client and server applications.", "[0045] [0045 ]FIG. 3 illustrates in greater detail selected portions of exemplary mobile switching center 140 that perform distributed call processing using group services in accordance with the principles of the present invention.", "MSC 140 comprises main processing unit (MPU) 310 , system manager node 1 (SYSMGR 1 ), optional system manager node 2 (SYSMGR 2 ), and master database 320 .", "MSC 140 also comprises a plurality of call application nodes (CANs), including CAN 1 , CAN 2 , and CAN 3 , and a plurality of local storage devices (SDs), namely SD 1 , SD 2 , and SD 3 , that are associated with CAN 1 , CAN 2 and CAN 3 .", "Master database 320 may be used as a master software repository to store databases, software images, server statistics, log-in data, and the like.", "SD 1 -SD 3 may be used to store local capsules, transient data, and the like.", "[0046] The system manager nodes 1 and 2 , collectively, and CAN 1 -CAN 3 execute a configuration management (CM) process that sets up each node with the appropriate software and configuration data upon initial start-up or after a reboot.", "Every node in the system also executes a node monitor (NM) process that loads software and tracks processes to determine if any process has failed.", "System manager nodes 1 and 2 execute a first arbitrary process, P 1 , and system manager node 1 also executes a second arbitrary process, P 2 .", "[0047] In accordance with the principles of the present invention, call application nodes 1 - 3 (CAN 1 -CAN 3 ) execute a number of call process (CP) server applications organized as primary and backup processes that are available as distributed group services to 1 to N call process client (CPC) applications, namely CPC APP 1 -CPC APPn in main processing unit 310 .", "The N call application nodes (e.g., CAN 1 -CAN 3 ) are separate computing nodes comprising a processor and memory that provide scalability and redundancy by the simple addition of more call application nodes.", "[0048] Each of the N call process client (CPC) applications, namely CPC APP 1 -CPC APPn in MPU 310 handles the control signals and messages related to a single call associated with a mobile station.", "Each of CPC APP 1 -CPC APPn establishes a session with a load sharing group, which assigns the call to a particular one of the primary-backup group call process server applications, CP 1 , CP 2 , or CP 3 .", "The selected call process server application actually performs the call process services/functions requested by the call process client application.", "[0049] In the illustrated embodiment, three exemplary call process server applications are being executed, namely CP 1 , CP 2 , and CP 3 .", "Each of these processes exists as a primary-backup group.", "Thus, CP 1 exists as a primary process, CP 1 (P), and a backup process, CP 1 (B).", "Similarly, CP 2 exists as a primary process, CP 2 (P), and a backup process, CP 2 (B), and CP 3 exists as a primary process, CP 3 (P), and a backup process, CP 3 (B).", "In the illustrated embodiment, CP 1 (P) and CP 1 (B) reside on different call application nodes (i.e., CAN 1 and CAN 2 ).", "This is not a strict requirement: CP 1 (P) and CP 1 (B) may reside on the same call application node (e.g., CAN 1 ) and still provide reliability and redundancy for software failures of the primary process, CP 1 (P).", "However, in a preferred embodiment of the present invention, the primary process and the backup process reside on different call application nodes, thereby providing hardware redundancy as well as software redundancy.", "Thus, CP 1 (P) and CP 1 (B) reside on CAN 1 and CAN 2 , CP 2 (P) and CP 2 (B) reside on CAN 2 and CAN 3 , and CP 3 (P) and CP 3 (B) reside on CAN 3 and CAN 1 .", "[0050] Together, CP 1 , CP 2 and CP 3 form a supergroup for load sharing purposes.", "Thus, CP 1 (P) and CP 1 (B), CP 2 (P) and CP 2 (B), and CP 3 (P) and CP 3 (B) are part of a first load sharing group (LSG 1 ), indicated by the dotted line boundary.", "Additionally, CAN 1 -CAN 3 host three other load sharing groups, namely, LSG 2 , LSG 3 , and LSG 4 .", "LSG 2 comprises two trunk idle list (TIL) server applications, namely TIL 1 and TIL 2 .", "TIL 1 exists as a primary process, TIL 1 (P), on CAN 2 and a backup process, TIL 1 (B), on CAN 3 .", "TIL 2 exists as a primary process, TIL 2 (P), on CAN 3 and a backup process, TIL 2 (B), on CAN 2 .", "Similarly, LSG 3 comprises two identity server (IS) applications, namely IS 1 and IS 2 .", "IS 1 exists as a primary process, IS 1 (P), on CAN 1 and a backup process, IS 1 (B), on CAN 2 and IS 2 exists as a primary process, IS 2 (P), on CAN 2 and a backup process, IS 2 (B), on CAN 1 .", "Finally, LSG 4 comprises two subscriber database (SDB) server applications, namely SDB 1 and SDB 2 .", "SDB 1 exists as a primary process, SDB 1 (P), on CAN 2 and a backup process, SDB 1 (B), on CAN 3 and SDB 2 exists as a primary process, SDB 2 (P), on CAN 3 and a backup process, SDB 2 (B), on CAN 2 .", "[0051] A group service provides a framework for organizing a group of distributed software objects in a computing network.", "Each software object provides a service.", "In addition, the group service framework provides enhanced behavior for determining group membership, deciding what actions to take in the presence of faults, and controlling unicast, multicast, and groupcast communications between members and clients for the group.", "A group utilizes a policy to enhance the behavior of the services provided by the group.", "Some of these policies include primary-backup for high service availability and load sharing for distributing the loading of services within a network.", "[0052] Call process server applications, such as CP 1 -CP 3 , IS 1 -IS 2 , and TIL 1 -TIL 2 , located within a computing network provide services that are invoked by client applications, such as CPC APP 1 -CPC APPn.", "As shown in FIG. 3, the call process server applications are organized into primary-backup groups configured as a 1+1 type of primary-backup group.", "There are multiple numbers of these primary-backup groups and the exact number is scalable according to the number of processes and/or computing nodes (CANs) that are used.", "All of the primary-backup groups are themselves a member of a single load sharing group (e.g., LSG 1 , LSG 2 , LSG 3 , LSG 4 ).", "[0053] It is important to note that while the call process client applications, CPC APP 1 -CPC APPn, are clients with respect to the call process server applications, CP 1 , CP 2 , and CP 3 , a server application may be a client with respect to another server application.", "In particular, the call process server applications CP 1 -CP 3 may be clients with respect to the trunk idle list server applications, TIL 1 and TIL 2 , the subscriber database server applications, SDB 1 and SDB 2 , and the identity server applications, IS 1 and IS 2 .", "[0054] A client application establishes an interface to the load sharing group.", "When a new call indication is received by the client application, the client application establishes a session with the load sharing group according to a client-side load sharing policy.", "The initial server (CP 1 , CP 2 , etc.) selection policy is CPU utilization-based (i.e., based on the processor load in each of the candidate CANs, with more lightly loaded groups selected first), but other algorithmic policies, such as round-robin (i.e., distribution of new calls in sequential order to each CAN) may be used.", "[0055] The client application associates the session with the new call and sends messages associated with the call over the session object.", "The client application also receives messages from the primary-backup group via the session established with the primary-backup group.", "Only the primary process (e.g., CP 1 (P)) of the primary-backup group joins the load sharing group (e.g., LSG 1 ).", "[0056] For a variety of reasons, the application containing the primary may be removed from service.", "With the removal of the primary member, the backup member becomes the primary and the server application is no longer a member of the load sharing group.", "However, the client application(s) still maintain their session with the primary-backup group for existing calls.", "New calls are not distributed to the primary-backup group if it is not a member of the load sharing group.", "[0057] If the primary of the primary-backup group that is a member of the load sharing group should fail, the backup member is informed that the primary member has failed (or left) and then assumes the role of primary member.", "The responsibility for these actions must be performed by the server application.", "It is the responsibility of the Group Service to inform the backup member that the primary member has failed or left.", "[0058] As part of an online software upgrade process, one or more applications containing primary-backup groups may be removed from service, brought down, and then brought back up using a new version of software code.", "These groups, if their interface has not changed, join the existing load sharing group.", "When first started, it is required that the client interface be capable of throttling the call traffic to specific primary-backup groups.", "The traffic throttling is expressed as a percentage varying from 0% (no calls) to 100%.", "All new calls that would have been scheduled according to the scheduling algorithm are handled by this session.", "The throttling factor is initialized to 100% for any primary-backup group that joins the load sharing group.", "During on-line software upgrades, the throttling factor is adjusted to start with the no-calls case for the new software version.", "Any client application for the load sharing group may establish a session with a specific primary-backup group.", "The client may then change the throttling factor at any time.", "When the throttling factor is changed, all client session interfaces receive via multicast the changed throttling factor.", "As the throttling factor is increased, the call process server applications with the new software version may receive increasing amounts of call traffic.", "[0059] Call processing communications from the client applications to the call processing server primary-backup groups must support a very high volume of calls.", "The group software utilizes an internal transport consisting of a multicasting protocol (simple IP multicast) and optionally a unicasting protocol.", "The unicasting protocol may be TCP/IP, SCTP, or other transport protocol.", "The multicast protocol is used for internal member communications relating to membership, state changes, and fault detection.", "In the absence of unicast transport, the multicast protocol is used for client/server communication streams.", "The unicast protocol, when provided, is used to provide a high-speed stream between clients and servers.", "The stream is always directed to the primary of a primary-backup group, which is transparent to both the call processing client application and the call process (e.g., CP 1 , CP 2 , CP 3 , TIL 1 , TIL 2 , IS 1 , IS 2 ).", "[0060] AS noted above, the call processes on the call application nodes (CANs) are organized into a load sharing group.", "Each call process (e.g., CP 1 , CP 2 , CP 3 , TIL 1 , TIL 2 , IS 1 , IS 2 ) is itself a primary-backup group.", "Both members of the primary-backup group may provide the service but only the primary of the group receives messages and thus actually provides the service.", "When a member of the group is selected as the primary, it registers one or more interface streams for the group.", "Each stream is a separate interface for some call processing service.", "[0061] The call processing client application (e.g., CPC APP 1 , CPC APP 2 ) in MSC 140 receives a new call indication and uses the group service to select an interface with a call application node (i.e., server) to handle the new call.", "The call process on each server (CAN) is a member of a load sharing group and a particular call application node (CAN) is selected on a CPU utilization (i.e., load) basis or other algorithmic basis (such as round-robin) from the perspective of the call process client application.", "For the particular primary-backup group that is selected a session is returned to the call processing client application.", "When the session is established with the primary-backup call process server group, the call processing client application then opens an interface to a particular member (representing an interface to a primary-backup group) and obtains a session interface.", "Each call processing server sends a message related to the new call over the session interface.", "Any subsequent transactions associated with the call are sent over the same session object.", "[0062] The call process server (i.e., primary-backup group) may asynchronously send messages over the session using one or more of the defined stream interfaces.", "The primary member of the call processing server group receives the transactions.", "The backup group member does not receive transactions.", "The primary group member sends updates to the backup group member.", "In an exemplary embodiment of the present invention, the primary group member decides when updates are sent to the backup group member.", "The primary starts sending updates when a call has been answered.", "Prior to the call being answered, the call is defined as being a transient call.", "After the call has been answered, the call is defined as being a stable call.", "The present invention protects stable calls from failures, but not transient calls.", "However, earlier and more frequent updates from the primary to the backup could also protect transient calls from failures.", "[0063] If the primary group member should fail, then the backup group member becomes the new primary member.", "According to the exemplary embodiment of the present invention, all transient call information during the fail-over period (the time between when the primary fails and the backup is changed to be the new primary) can be lost, but all stable call information is maintained by the backup.", "[0064] Advantageously, the present invention has no limitations on the scalability of the system and the system size is hidden from both and the primary-backup group server applications and call process client applications.", "The present invention eliminates any single point of failure in the system.", "Any failure within the system will not affect the system availability and performance.", "[0065] New call application nodes (CANs) and additional primary-backup group server applications (e.g., CP 1 , CP 2 , CP 3 , TIL 1 , TIL 2 , IS 1 , IS 2 ) may be added dynamically to the load sharing groups and can start servicing new call traffic.", "Call process client applications are not affected by the additions of new servers.", "If a server should fail, its backup assumes responsibility for the load.", "This provides high availability for the servicing of each call and minimizes dropped calls.", "[0066] Advantageously, the redundant architecture of call application nodes 1 - 3 (i.e., CAN 1 -CAN 3 ) and the use of primary-backup group server applications in mobile switching center 140 provides for a unique method for upgrading the call process server applications in MSC 140 without interrupting existing service.", "According to the principles of the present invention, each primary-backup group server application on each of CAN 1 -CAN 3 may be gracefully shutdown in order to effect a partitioning of a target call application node.", "The target call application node may then be upgraded to new primary-backup group server application software and the upgraded software may gradually be brought on-line and joined to load sharing groups using a throttling mechanism.", "Once the upgraded software is tested and fully operational, the process is continually repeated at the next targeted call application node until all call application nodes have been upgraded.", "[0067] [0067 ]FIG. 4 depicts flow diagram 400 , which illustrates the partitioning and on-line upgrade of primary-backup group server applications in mobile switching center 140 in accordance with the principles of the present invention.", "Initially, system manager node 1 may automatically (or maintenance personnel may manually) designate a first target call application node (e.g., CAN 1 ) to be upgraded (process step 405 ).", "Each primary call process Cpx(P) of a primary-backup group call process server application on the first target call application node is disabled and the corresponding backup call process CPx(B) on a different call application node (e.g., CAN 2 ) becomes the new primary call process.", "At this point, the new primary call process runs without a backup process.", "However, no call new traffic is sent to the new primary call process.", "Thus, the CPx primary-backup group eventually shuts down as existing calls disconnect (process step 410 ).", "[0068] Since the first target call application node may host one or more backup call processes related to primary call processes executed on other call application nodes, the present invention next moves all backup call processes CPy(B) on the first target call application node to different call application nodes (process step 415 ).", "The first target call application node is now free of all primary and backup call processes.", "The first target call application node is now a new partition and the remaining call applications are part of the old partition.", "[0069] Next, the upgraded software for the primary call process CPx(P)* is installed and the backup call process CPx(B)* is created in the first target call application node.", "This new primary-backup group call process server application then joins the appropriate load sharing group (i.e., LSG 1 ).", "At this point, the new primary server application is receiving no traffic.", "Thereafter, increasing amounts of new call traffic are sent to the upgraded primary call process Cpx(P)* using a throttling mechanism controlled by the craftsperson (or algorithmically by the system manager) until upgraded primary-backup group Cpx* operates at 100% (process step 420 ).", "[0070] Thereafter, steps 405 , 410 , 415 , 420 are repeated for a second target call application node (e.g., CAN 2 ) so that an upgraded primary call process CPz(P)* and an upgraded backup call process CPz(B)* are installed (or created) and operating on the second target call application node (process step 425 ).", "The second call target call application node is now part of the new partition, along with the first target call application node.", "[0071] Finally, the managing software application swaps the locations of the backup call processes CPx(B)* and Cpz(B)* so that the primary and backup call processes are not running on the same call application nodes (process step 430 ).", "The upgrade process then continues on to other call application nodes until all remaining call application nodes have joined the new partition and the old partition (containing the old software) ceases to exist.", "[0072] FIGS. 5 A- 5 K are a sequence of views of the call application nodes in exemplary mobile switching center (MSC) 140 as the call application nodes undergo the partitioning and on-line upgrade process illustrated in FIG. 4. [0073] [0073 ]FIG. 5A illustrates the initial view of CAN 1 -CAN 3 in mobile switching center 140 .", "[0074] In FIG. 5B, primary call process CP 1 (P) in CAN 1 has be terminated and the related backup call process CP 1 (B) in CAN 2 has become the new primary call process CP 1 (P).", "No new traffic is directed to CP 1 (P) in CAN 2 .", "Also, the backup call process CP 3 (B) has been moved to CAN 2 .", "[0075] In FIG. 5C, new updated primary call process CP 1 (P)* has been installed in CAN 1 and new updated backup call process CP 1 (B)* has been created in CAN 1 .", "New call traffic can now be directed to primary call process CP 1 (P)* in increasing increments until new updated primary-backup group call process server application CP 1 * is fully functional.", "[0076] In FIG. 5D, the old call process CP 1 (P) in CAN 2 has finally shut down through termination of all existing calls.", "[0077] In FIG. 5E, primary call process CP 2 (P) in CAN 2 has be terminated and the related backup call process CP 2 (B) in CAN 3 has become the new primary call process CP 2 (P).", "No new traffic is directed to CP 2 (P) in CAN 3 .", "Also, the backup call process CP 3 (B) has been moved to CAN 3 .", "[0078] In FIG. 5F, new updated primary call process CP 2 (P)* has been installed in CAN 2 and new updated backup call process CP 2 (B)* has been created in CAN 2 .", "New call traffic can now be directed to primary call process CP 2 (P)* in increasing increments until new updated primary-backup group call process server application CP 2 * is fully functional.", "[0079] In FIG. 5G, the old call process CP 2 (P) in CAN 3 has finally shut down through termination of all existing calls.", "[0080] In FIG. 5H, the backup call processes CP 1 (B)* and CP 2 (B)* switch locations in CAN 1 and CAN 2 .", "[0081] In FIG. 5I, primary call process CP 3 (P) in CAN 3 has been starved for new calls by leaving the load sharing group.", "The primary call process CP 3 (P) and its associated backup process CP 3 (B) have been terminated after all existing call traffic ended.", "[0082] In FIG. 5J, new updated primary call process CP 3 (P)* has been installed in CAN 3 and new updated backup call process CP 3 (B)* has been created in CAN 3 .", "New call traffic can now be directed to primary call process CP 3 (P)* in increasing increments until new updated primary-backup group call process server application CP 3 * is fully functional.", "[0083] In FIG. 5K, the locations of backup call processes CP 1 (B)*, CP 2 (B)*, and CP 3 (B)* have been rotated in CAN 1 , CAN 2 , and CAN 3 to achieve the original configuration illustrated in FIG. 5A.", "[0084] Although the present invention has been described in detail, those skilled in the art should understand that they may make various changes, substitutions and alterations herein without departing from the spirit and scope of the invention in its broadest form." ]
FIELD OF THE INVENTION [0001] The invention relates to methods and systems for designing, assembling and producing a connecting device within an article box suitable for dispensing a product, and preferably tissue, when said article box is located in a moving surrounding. The purview of the present invention extends to methods and systems for designing and processing at least a part of a first article box for adapting and/or connecting said first box, to at least a second article holder that are described herein and, in particular, methods and systems for processing an article box, preferably a tissue dispensing carton box to adapt at least one of its component, for connecting with a second holder body, preferably a travel holder such as a cup holder located in a vehicle, for example an automobile. BACKGROUND [0002] Latest advances in packaging consumer products for personal use that include features suitable for mobile use, such as in the case of travel, promise benefit to consumer. For example, most current vehicles, in particular automobiles, are equipped with a multitude of article holders for storing, positioning and/or powering a multitude of portable or personal electronic appliances and/or their ancillaries, such as mobile phones, digital media players (e.g. MP3 device, video player, videogame console, or the like), personal computer, including accessories (e.g. USB memory stick, wireless connectivity device), camera and any other digital, communication or entertainment device readily available under current commercial standards. Most of these electronic articles may be affixed to their surrounding environment, for example the dashboard or a cup holder of a car, through readily available adaptation fixtures (i.e. independent or isolated holder) that can connect and secure the articles to their surrounds, in particular to defined location to prevent motion while allowing functional, and within specifications, operation (e.g. energy charging). [0003] There are many consumer products ranging from cosmetics, health care, hygiene, food and so on that comprise articles packaged in a container, for example a carton box, to be delivered, dispensed or used by manual intervention of a consumer such as an individual or a person who may be engaged in a moving action, for example when undergoing transportation or driving a vehicle. A working point for the sake of clarification is now established by referencing article meaning an item to be used or consumed as a product or part thereof (e.g. facial tissue, towel); a box meaning a container comprising, or suitable for receiving, at least one article; a connector meaning a body, part or mean to provide a physical link or bridge between at least two objects; a holder meaning an object which can receive or attach to said box. [0004] It is within the scope of the present invention to provide a suitable interface assembly connecting any of the previously described articles for securing handling in preferably a mobile surroundings, depending on the configuration and nature of the materials used for at least a surface or part of the package shaping said articles, for example a plastic, fabric or carton cover, bag, container or box, an adaptable surface, including a pliable surface, can be provided for handling and connecting of the article with a holder, clamp or other seating object to secure and optimize operational access of the article, for example in a mobile surrounding environment. It is also within the scope of the present invention to provide an article holding of said articles from the family of general description of consumer products, in particular assembling a box in a holder, said box having a multitude of dispensing functions, in particular dispensing of any component (e.g. solid, liquid, gas) contained within the interior or attached onto an exterior surface of the box, and that can be delivered with sufficient precision and functional integrity allowing a user to preserve safe and performing operations within the specifications of said consumer products (e.g. dispensing of facial tissue, hand sanitizer, air fresher) when operation may occur in a surrounding environment that can undergo motion. Although the present invention pertains to those skilled in the art of known prior art, the following description will be directed towards some preferred embodiments related to the combination of adapting, or assembling, or coupling, or engaging of an article box with a holding body. In particular, attention is now directed to the description of an embodiment comprising inserting at least a pliable surface of a first box body that can be deployed in close proximity with at least a few contact points on the surface of said a second holder body, said deployment generating sufficient physical interactions (e.g. friction) between both bodies that can provide assembly for safe, precise and functional operations in preferably a moving surrounding. In particular, a carton box dispenser of facial tissues can be designed and fabricated with at least one of its surface showing a predefined pattern of a connecting component that can be pre-cut in view of its multi-dimensional folding when brought in close proximity with the article holder that can be a cup holder in a car. [0005] Improved capacity in connecting both articles with shapes that can't easily fit their engagement to provide holding can be achieved with the present invention. By designing a pre-cut pattern of said connecting body on one of the surface of the carton box during its standard manufacturing combining processing (e.g. laser cutting, feature printing), precutting, folding and general assembling, any shaped box (e.g. cubic carton box dispensing tissue) can adapt to handle access and positioning within the surrounds of any shaped holder (e.g. circular cup holder) to provide secure positioning while preserving and/or improving dispensing operation, for example. Examples can include the secure and precise disposition of a carton tissue box in a car cup holder, onto a dashboard, a sun visor, air vent, arm or head rest of a seat, door handle or any surrounds of the interior of a vehicle, for example a car, airplane, train, bicycle, motorcycle, vessel, spacecraft or any vehicle that can accommodate an individual involved in a motion or transport. [0006] The prior art of designing upright dispensing box for facial tissue [U.S. Pat. No. 5,415,320] describes embodiments for optimizing the dispensing opening to prevent tearing of the tissue sheets upon removal. The present invention improves on optimizing dispensing of tissue sheets when removal occurs placing the box in a mobile surrounding environment, in particular under travel circumstances or transportation, preferably when the box is connected to a cup holder in an automobile. A multi-ply tissue product which can optimize packaging processing of the tissue sheets assembly while minimizing sloughing has been reported [U.S. Pat. No. 6,797,114B2], as well as cylindrical tissue dispenser that contains retainers to fit engage into a cylindrical cup holder, and other dispenser holder device that play the role of a body carrier inserted in the cylindrical cup holder and supporting the tissue box inserted into said carrier. U.S. Pat. No. 6,318,590 shows a tissue dispensing holder exclusively as a hollow cylindrical container. None of the above inventions or patents taken either singly or in combination, is seen to describe the novelty of the present invention as claimed. None of the above prior art reports adapting the most commercially readily available tissue box products, i.e. “cubic” or “rectangular” cumbersome carton dispenser boxes, to common cylindrical cup holders through at least one integrated connecting body that can be fabricated as a monolithic component of at least one surface of the said carton dispenser box. The present invention doesn't require any specific design of the box as per limiting design parameters and shapes of a cylindrical cup holder to accommodate fit and secure confinement. The present invention recognizes the problems associated with adapting dislike shaped tissue dispenser and holder articles of multiple shapes and functions for adapting said article box in a multitude of surrounds that are preferably part of a traveling body, and preferably in a vehicle, but also onto a movable device (e.g. portable medical instrumentation such as IV Pole, patient bed) to improve user interface for better or safer performance. Furthermore, the present invention provide integration and compatibility of processing for mass manufacturing leveraging standard tool sets that may require minor modification, for example duplication of a programming, pliable, printing, pre-cutting and packaging step to be performed during the manufacturing of the article box. Note the present invention is also considering a diversity of product content within the dispensing box, for example, swabs, towels, food such as candies or any other consumer product an individual may consume during a transport. SUMMARY [0007] Accordingly, the embodiments presented herein can provide methods and systems for designing, processing, manufacturing and distributing an article box for dispensing a product or component thereof when the user is involved in a mobile activity, preferably transport, travel, in particular in a vehicle, are described herein and, in particular, methods and systems for adapting connecting a first article box with dislike shape than a second article holder for the purpose of transport or travel. [0008] In one approach, the embodiments can include a method and system for integrating designing, and preferably automated processing of the connector into a standard step of the manufacturing of the article box. [0009] In one approach, the step of designing the connector using a digital CAD drawing algorithm can include the steps of mining databases for comparative design patterns; and comparing the pattern of the connector with a comparative pattern feature from the database. [0010] In one embodiment, the article comprises a cubic shaped carton-based tissue box with a pre-cut design of an orifice onto one of the wall of the cube with a connecting part that can be unfolded in three dimensions preferably into an asymmetric base connector that can then be inserted, for example, into a cylindrical car cup holder. The three-dimensional connecting part can provide friction with the surface of the cup holder and provide some adherence or adhesion between the tissue box and the cup holder allowing the interface of the tissue box with the cup holder that can be suitable for an individual or user to access the tissue sheets through the upper slit allowing the delivery of the tissue sheets for their usage in a mobile environment. Adjustments can then be made for preserving and/or improving the attachment of the tissue box into the cup holder by either complementary folding or applying a slight pressure onto the box, or adding surface treatment such as an adhesive layer or coating, rubber or other polymeric protrusion or the like. The system can optionally include a position and/or pressure sensing device or functional smart materials (e.g. thermo-responsive or piezoelectric materials) for an active coupling between the box and the cup holder that could take the role of a communication means for digital feedback indicating the level of adherence between the articles to ensure secure attachment for improving safety, ease, and efficiency of operations. [0011] Other features will become more apparent to persons having ordinary skill in the art to which the package pertains and from the following description and claims. BRIEF DESCRIPTION OF THE DRAWINGS [0012] The above and other aspects, features and advantages of the present embodiments will be more apparent from the following more particular description thereof, presented in conjunction with the following figures, wherein: [0013] FIG. 1 is a schematic overview of (i) the prior art teaching inserting symmetrical matching shapes of a cylindrical tissue box into a cylindrical cup holder and (ii) one embodiment of the present system and method to connect an article box of any shape to a holder of any shape using a pliable connector patterned onto at least one wall of said article box that can be unfolded to provide a mean to connect with a receiving holder. [0014] FIG. 2 (A,B,C,D) illustrate a multitude of design, shapes, materials that can be produced on the article box through integration during the manufacturing processing or as an independent part to be attached to said the article box and accordingly to several of the described embodiments. [0015] FIG. 3 is a system flow diagram in accordance with the method for designing, processing and deploying one embodiment of the invention shown in FIG. 1 ; and [0016] FIG. 4 emphasizes two preferred types of connection between two articles and, for example a tissue box and a cup holder allowing sufficient resistance between said articles to allow active delivery of the content of said tissue box, preferably during a motion. [0017] FIG. 5 illustrates a sequence of images illustrating the positioning and deployment of the preferred embodiment, i.e. a tissue box placed in proximity to a cup holder of dissimilar shapes providing a stable connection. [0018] Corresponding reference characters indicate corresponding components throughout the several views of the drawings. DETAILED DESCRIPTION [0019] The following description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of exemplary embodiments. The scope of the invention should be determined with reference to the claims. The present embodiments allow improved operability of a consumer product, in particular when packaged into a dispensing box such as tissue box. In particular, the present embodiments provide necessary components and processes to preferably integrate designing, fabricating of a connector means from the box which can then be brought in close proximity of a holder, such as a cup holder located in a vehicle, to accommodate a surround of the box in relative positioning between the box, holder and user when moving. Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. [0020] Despite advances in the art, improvements in consumer product delivery and consumer care are possible and desired. Such improvements could include faster, safer and more efficient locating, dispensing, and article usage. As an added benefit, these types of improvements could potentially also be applied to other areas of applications such as food dispensing, accessing information or any related user interface known in the prior art, including an individual or person under hospital stay in a patient bed, or moving with a IV pole. Other content of a box-type of packaged product for the purpose of continuous or sequential delivery or access of at least one component of said content is also within the scope of the present invention. For example, hardware parts such as screws, nails but also electronic components such as transistors, resistors, but also medications in the form of pills, tablets or any other component packaged into individual parts packaged in a box could be included providing similar benefits to the user as it was described previously. [0021] The following definitions are provided to assist in understanding some embodiments of the present methods and systems. Unless specifically defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art of the present embodiments. Generally, the nomenclature used herein and the manufacturing procedures in automated packaging assembly, consumer product manufacturing and distribution described below are well known and commonly employed in the art. Unless specifically described otherwise, conventional methods are used for the fabrication procedures, such as those provided in the art. Where a term is provided in the singular, the plural of that term should also be contemplated. The nomenclature used herein and general manufacturing procedures described herein are known and commonly employed in the art. As employed throughout the disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings: [0022] “Box” can be any container article and, for example, a tissue box, a towel box, or a package of a product suitable for consumption, for example, sheets of any materials (e.g. paper, textile, plastics), possibly in a controlled moisture environment, or under solar or any other external radiation protection. [0023] A “vehicle” is a means of transportation, for example a vehicle such as a train, a car, an automobile, a motorcycle, a vessel, an airplane or any other mode of transport known by those skilled in the art. [0024] A “user” is a person who is preferably interacting with a consumer product for its usage such as facial cleaning, controlling release of biological fluids (e.g. tissue for nose discharge, ear wax cleaning, etc.) or any other hygienic action while the person is engaged in an activity that involves motion, transportation, travel or the like. [0025] Turning now to the figures, FIG. 1 a illustrates a schematic overview of some prior art described in U.S. Pat. No. 6,318,590B1 issued to McMurray-Stivers, and FIG. 1 b - c show the diagrams of the present invention illustrating its novelty over the prior art. McMurray-Stivers introduces a cylindrical dispenser - 10 - that requires insertion into a cylindrical cup holder - 12 - of same symmetry and of closely similar dimensions, through retention means - 14 - all around the cylindrical circumference of the dispenser, to exert pressure and friction with the sidewalls of the symmetrical cup holder to hold position. This embodiment requires adjusting the dimensions and symmetry of the dispenser and cup holder in tight control within tolerances of the size of the retention means, typically within a few millimeters. So, the diameter 2×R1 of the dispenser has almost similar dimensions than the diameter of the cup holder 2×R2, and in the relation of R1˜R2. The present invention provides a novel method and apparatus that allow connecting any shaped article (e.g. dispenser) - 16 - to any shaped receiving article (e.g. cup holder) - 12 - through a connector - 18 - that is integrated within a wall of said first article which can be released into a three-dimensional arrangement - 20 - suitable for holding all articles. It is also obvious to those skilled in the art that the present invention also has several benefits during the manufacturing as the connector can be designed and fabricated during the conventional processing steps of conventional packaging manufacturing conditions. The arrangement - 20 - can comprise at least one component that can fold in a spatial configuration such as three-dimensional means that can interact, for example, through a mechanical force (e.g. friction, adhesion) or an electromagnetic force or field gradient in the case of an active actuation (e.g. electromagnet) that can be generated when a power source could be connected between the said articles. For example, the arrangement can allow versatile adjustment either through a constant or a variable physical interaction between said a dispenser -A- and a cup holder - 12 - suitable for connecting articles that can be dislike in shape, geometry, materials composition or any physico-chemical properties that may be of relevance to the intrinsic nature of the individual articles. The present invention provides capacity of engaging connecting articles in different relationships, such as A≠R2 or for example in the case of a second article such as a cup holder with dimensions A>D2>D3, as it is illustrated in FIG. 1C . Note that the article - 16 - preferably will comprise an opening means - 22 - on one of its walls for dispensing the content of said article (e.g. a tissue sheet). [0026] FIG. 2 (A,B,C,D) illustrate examples of a multitude of geometrical and spatial designs and configurations with 3-D and top view illustrations of a preferred embodiment of a tissue box - 16 - and its connector arrangement - 18 - and components - 20 that can be arranged in a symmetrical pattern (e.g. FIG. 2 A,B,C), such as a clover motif (e.g. FIG. 2B ) or in asymmetrical pattern (e.g. FIG. 2D ) which may also contain sub-components 24 - 30 suitable to assist individually or in combination during the mechanism of connecting said box to said holder. For example, a sub-component can be a curve line defining a random pattern connector that can be pliable, or including pillar - 26 -, groove - 28 , rod - 30 - or any other combination of shaped sub-component such as anchor-like object - 32 -. Now attention is directed towards FIG. 3 showing a preferred embodiment of a tissue box - 40 - with a dispensing opening - 42 - onto one of its walls (e.g. top wall) and a pliable pattern comprising a connector that can be comprised of at least a part - 44 - and a supporting part - 46 -. FIG. 3 a , shows a top view of an unfolded two dimensional diagram of one of the preferred embodiment of the present invention, while FIG. 3 b illustrates a three-dimensional view of the invention. FIG. 3 c illustrates a sequence of steps for the spatial deployment of the connector of one preferred embodiment of the present invention. For example, the wall - 48 - of the tissue box will represent the bottom surface which can then be inserted in a holder that can allow securing a typical cubic and commercially available tissue box into the cup holder of a car so that a driver or passenger could access the content of the box and dispense tissue safely and accurately while the vehicle may be in motion. FIG. 4 illustrates another preferred embodiment placing a first cubic article - 50 - with its unfolded connector - 52 - inserted into a second article of dissimilar shape, for example a cylindrical cup holder, wherein a configuration can comprise a connector surface is directly engaged in a frictional force with the walls of the cup holder to apply pressure and provide safe attachment of said box and allowing active delivery of the content - 56 - without significantly unlocking the position of both articles. A configuration using discrete part thereof - 58 - of the connector - 52 - for positioning and locking the first article in close proximity of said second article by exerting contact and possibly pressure of parts - 58 - with the wall of the holder - 54 - is also illustrated in the FIG. 4 . [0027] While the figures and descriptions herein have been described in conjunction with specific embodiments, many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Changes in form, as well as substitution of equivalents, are contemplated as circumstances may suggest or render expedient.
A secure and integrated matching of a consumer product box of dissimilar shapes and characteristics to a receiving holder from a moving environmental surroundings, can include a connector configured to selectively connect and position at least one wall from said the box to link with the receiving holder. In a preferred embodiment, the present method and apparatus is suitable for holding a tissue box of any shape in a cup holder of any shape in a vehicle, for example a car.
Briefly describe the main idea outlined in the provided context.
[ "FIELD OF THE INVENTION [0001] The invention relates to methods and systems for designing, assembling and producing a connecting device within an article box suitable for dispensing a product, and preferably tissue, when said article box is located in a moving surrounding.", "The purview of the present invention extends to methods and systems for designing and processing at least a part of a first article box for adapting and/or connecting said first box, to at least a second article holder that are described herein and, in particular, methods and systems for processing an article box, preferably a tissue dispensing carton box to adapt at least one of its component, for connecting with a second holder body, preferably a travel holder such as a cup holder located in a vehicle, for example an automobile.", "BACKGROUND [0002] Latest advances in packaging consumer products for personal use that include features suitable for mobile use, such as in the case of travel, promise benefit to consumer.", "For example, most current vehicles, in particular automobiles, are equipped with a multitude of article holders for storing, positioning and/or powering a multitude of portable or personal electronic appliances and/or their ancillaries, such as mobile phones, digital media players (e.g. MP3 device, video player, videogame console, or the like), personal computer, including accessories (e.g. USB memory stick, wireless connectivity device), camera and any other digital, communication or entertainment device readily available under current commercial standards.", "Most of these electronic articles may be affixed to their surrounding environment, for example the dashboard or a cup holder of a car, through readily available adaptation fixtures (i.e. independent or isolated holder) that can connect and secure the articles to their surrounds, in particular to defined location to prevent motion while allowing functional, and within specifications, operation (e.g. energy charging).", "[0003] There are many consumer products ranging from cosmetics, health care, hygiene, food and so on that comprise articles packaged in a container, for example a carton box, to be delivered, dispensed or used by manual intervention of a consumer such as an individual or a person who may be engaged in a moving action, for example when undergoing transportation or driving a vehicle.", "A working point for the sake of clarification is now established by referencing article meaning an item to be used or consumed as a product or part thereof (e.g. facial tissue, towel);", "a box meaning a container comprising, or suitable for receiving, at least one article;", "a connector meaning a body, part or mean to provide a physical link or bridge between at least two objects;", "a holder meaning an object which can receive or attach to said box.", "[0004] It is within the scope of the present invention to provide a suitable interface assembly connecting any of the previously described articles for securing handling in preferably a mobile surroundings, depending on the configuration and nature of the materials used for at least a surface or part of the package shaping said articles, for example a plastic, fabric or carton cover, bag, container or box, an adaptable surface, including a pliable surface, can be provided for handling and connecting of the article with a holder, clamp or other seating object to secure and optimize operational access of the article, for example in a mobile surrounding environment.", "It is also within the scope of the present invention to provide an article holding of said articles from the family of general description of consumer products, in particular assembling a box in a holder, said box having a multitude of dispensing functions, in particular dispensing of any component (e.g. solid, liquid, gas) contained within the interior or attached onto an exterior surface of the box, and that can be delivered with sufficient precision and functional integrity allowing a user to preserve safe and performing operations within the specifications of said consumer products (e.g. dispensing of facial tissue, hand sanitizer, air fresher) when operation may occur in a surrounding environment that can undergo motion.", "Although the present invention pertains to those skilled in the art of known prior art, the following description will be directed towards some preferred embodiments related to the combination of adapting, or assembling, or coupling, or engaging of an article box with a holding body.", "In particular, attention is now directed to the description of an embodiment comprising inserting at least a pliable surface of a first box body that can be deployed in close proximity with at least a few contact points on the surface of said a second holder body, said deployment generating sufficient physical interactions (e.g. friction) between both bodies that can provide assembly for safe, precise and functional operations in preferably a moving surrounding.", "In particular, a carton box dispenser of facial tissues can be designed and fabricated with at least one of its surface showing a predefined pattern of a connecting component that can be pre-cut in view of its multi-dimensional folding when brought in close proximity with the article holder that can be a cup holder in a car.", "[0005] Improved capacity in connecting both articles with shapes that can't easily fit their engagement to provide holding can be achieved with the present invention.", "By designing a pre-cut pattern of said connecting body on one of the surface of the carton box during its standard manufacturing combining processing (e.g. laser cutting, feature printing), precutting, folding and general assembling, any shaped box (e.g. cubic carton box dispensing tissue) can adapt to handle access and positioning within the surrounds of any shaped holder (e.g. circular cup holder) to provide secure positioning while preserving and/or improving dispensing operation, for example.", "Examples can include the secure and precise disposition of a carton tissue box in a car cup holder, onto a dashboard, a sun visor, air vent, arm or head rest of a seat, door handle or any surrounds of the interior of a vehicle, for example a car, airplane, train, bicycle, motorcycle, vessel, spacecraft or any vehicle that can accommodate an individual involved in a motion or transport.", "[0006] The prior art of designing upright dispensing box for facial tissue [U.S. Pat. No. 5,415,320] describes embodiments for optimizing the dispensing opening to prevent tearing of the tissue sheets upon removal.", "The present invention improves on optimizing dispensing of tissue sheets when removal occurs placing the box in a mobile surrounding environment, in particular under travel circumstances or transportation, preferably when the box is connected to a cup holder in an automobile.", "A multi-ply tissue product which can optimize packaging processing of the tissue sheets assembly while minimizing sloughing has been reported [U.S. Pat. No. 6,797,114B2], as well as cylindrical tissue dispenser that contains retainers to fit engage into a cylindrical cup holder, and other dispenser holder device that play the role of a body carrier inserted in the cylindrical cup holder and supporting the tissue box inserted into said carrier.", "U.S. Pat. No. 6,318,590 shows a tissue dispensing holder exclusively as a hollow cylindrical container.", "None of the above inventions or patents taken either singly or in combination, is seen to describe the novelty of the present invention as claimed.", "None of the above prior art reports adapting the most commercially readily available tissue box products, i.e. “cubic”", "or “rectangular”", "cumbersome carton dispenser boxes, to common cylindrical cup holders through at least one integrated connecting body that can be fabricated as a monolithic component of at least one surface of the said carton dispenser box.", "The present invention doesn't require any specific design of the box as per limiting design parameters and shapes of a cylindrical cup holder to accommodate fit and secure confinement.", "The present invention recognizes the problems associated with adapting dislike shaped tissue dispenser and holder articles of multiple shapes and functions for adapting said article box in a multitude of surrounds that are preferably part of a traveling body, and preferably in a vehicle, but also onto a movable device (e.g. portable medical instrumentation such as IV Pole, patient bed) to improve user interface for better or safer performance.", "Furthermore, the present invention provide integration and compatibility of processing for mass manufacturing leveraging standard tool sets that may require minor modification, for example duplication of a programming, pliable, printing, pre-cutting and packaging step to be performed during the manufacturing of the article box.", "Note the present invention is also considering a diversity of product content within the dispensing box, for example, swabs, towels, food such as candies or any other consumer product an individual may consume during a transport.", "SUMMARY [0007] Accordingly, the embodiments presented herein can provide methods and systems for designing, processing, manufacturing and distributing an article box for dispensing a product or component thereof when the user is involved in a mobile activity, preferably transport, travel, in particular in a vehicle, are described herein and, in particular, methods and systems for adapting connecting a first article box with dislike shape than a second article holder for the purpose of transport or travel.", "[0008] In one approach, the embodiments can include a method and system for integrating designing, and preferably automated processing of the connector into a standard step of the manufacturing of the article box.", "[0009] In one approach, the step of designing the connector using a digital CAD drawing algorithm can include the steps of mining databases for comparative design patterns;", "and comparing the pattern of the connector with a comparative pattern feature from the database.", "[0010] In one embodiment, the article comprises a cubic shaped carton-based tissue box with a pre-cut design of an orifice onto one of the wall of the cube with a connecting part that can be unfolded in three dimensions preferably into an asymmetric base connector that can then be inserted, for example, into a cylindrical car cup holder.", "The three-dimensional connecting part can provide friction with the surface of the cup holder and provide some adherence or adhesion between the tissue box and the cup holder allowing the interface of the tissue box with the cup holder that can be suitable for an individual or user to access the tissue sheets through the upper slit allowing the delivery of the tissue sheets for their usage in a mobile environment.", "Adjustments can then be made for preserving and/or improving the attachment of the tissue box into the cup holder by either complementary folding or applying a slight pressure onto the box, or adding surface treatment such as an adhesive layer or coating, rubber or other polymeric protrusion or the like.", "The system can optionally include a position and/or pressure sensing device or functional smart materials (e.g. thermo-responsive or piezoelectric materials) for an active coupling between the box and the cup holder that could take the role of a communication means for digital feedback indicating the level of adherence between the articles to ensure secure attachment for improving safety, ease, and efficiency of operations.", "[0011] Other features will become more apparent to persons having ordinary skill in the art to which the package pertains and from the following description and claims.", "BRIEF DESCRIPTION OF THE DRAWINGS [0012] The above and other aspects, features and advantages of the present embodiments will be more apparent from the following more particular description thereof, presented in conjunction with the following figures, wherein: [0013] FIG. 1 is a schematic overview of (i) the prior art teaching inserting symmetrical matching shapes of a cylindrical tissue box into a cylindrical cup holder and (ii) one embodiment of the present system and method to connect an article box of any shape to a holder of any shape using a pliable connector patterned onto at least one wall of said article box that can be unfolded to provide a mean to connect with a receiving holder.", "[0014] FIG. 2 (A,B,C,D) illustrate a multitude of design, shapes, materials that can be produced on the article box through integration during the manufacturing processing or as an independent part to be attached to said the article box and accordingly to several of the described embodiments.", "[0015] FIG. 3 is a system flow diagram in accordance with the method for designing, processing and deploying one embodiment of the invention shown in FIG. 1 ;", "and [0016] FIG. 4 emphasizes two preferred types of connection between two articles and, for example a tissue box and a cup holder allowing sufficient resistance between said articles to allow active delivery of the content of said tissue box, preferably during a motion.", "[0017] FIG. 5 illustrates a sequence of images illustrating the positioning and deployment of the preferred embodiment, i.e. a tissue box placed in proximity to a cup holder of dissimilar shapes providing a stable connection.", "[0018] Corresponding reference characters indicate corresponding components throughout the several views of the drawings.", "DETAILED DESCRIPTION [0019] The following description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of exemplary embodiments.", "The scope of the invention should be determined with reference to the claims.", "The present embodiments allow improved operability of a consumer product, in particular when packaged into a dispensing box such as tissue box.", "In particular, the present embodiments provide necessary components and processes to preferably integrate designing, fabricating of a connector means from the box which can then be brought in close proximity of a holder, such as a cup holder located in a vehicle, to accommodate a surround of the box in relative positioning between the box, holder and user when moving.", "Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention.", "Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.", "[0020] Despite advances in the art, improvements in consumer product delivery and consumer care are possible and desired.", "Such improvements could include faster, safer and more efficient locating, dispensing, and article usage.", "As an added benefit, these types of improvements could potentially also be applied to other areas of applications such as food dispensing, accessing information or any related user interface known in the prior art, including an individual or person under hospital stay in a patient bed, or moving with a IV pole.", "Other content of a box-type of packaged product for the purpose of continuous or sequential delivery or access of at least one component of said content is also within the scope of the present invention.", "For example, hardware parts such as screws, nails but also electronic components such as transistors, resistors, but also medications in the form of pills, tablets or any other component packaged into individual parts packaged in a box could be included providing similar benefits to the user as it was described previously.", "[0021] The following definitions are provided to assist in understanding some embodiments of the present methods and systems.", "Unless specifically defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art of the present embodiments.", "Generally, the nomenclature used herein and the manufacturing procedures in automated packaging assembly, consumer product manufacturing and distribution described below are well known and commonly employed in the art.", "Unless specifically described otherwise, conventional methods are used for the fabrication procedures, such as those provided in the art.", "Where a term is provided in the singular, the plural of that term should also be contemplated.", "The nomenclature used herein and general manufacturing procedures described herein are known and commonly employed in the art.", "As employed throughout the disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings: [0022] “Box”", "can be any container article and, for example, a tissue box, a towel box, or a package of a product suitable for consumption, for example, sheets of any materials (e.g. paper, textile, plastics), possibly in a controlled moisture environment, or under solar or any other external radiation protection.", "[0023] A “vehicle”", "is a means of transportation, for example a vehicle such as a train, a car, an automobile, a motorcycle, a vessel, an airplane or any other mode of transport known by those skilled in the art.", "[0024] A “user”", "is a person who is preferably interacting with a consumer product for its usage such as facial cleaning, controlling release of biological fluids (e.g. tissue for nose discharge, ear wax cleaning, etc.) or any other hygienic action while the person is engaged in an activity that involves motion, transportation, travel or the like.", "[0025] Turning now to the figures, FIG. 1 a illustrates a schematic overview of some prior art described in U.S. Pat. No. 6,318,590B1 issued to McMurray-Stivers, and FIG. 1 b - c show the diagrams of the present invention illustrating its novelty over the prior art.", "McMurray-Stivers introduces a cylindrical dispenser - 10 - that requires insertion into a cylindrical cup holder - 12 - of same symmetry and of closely similar dimensions, through retention means - 14 - all around the cylindrical circumference of the dispenser, to exert pressure and friction with the sidewalls of the symmetrical cup holder to hold position.", "This embodiment requires adjusting the dimensions and symmetry of the dispenser and cup holder in tight control within tolerances of the size of the retention means, typically within a few millimeters.", "So, the diameter 2×R1 of the dispenser has almost similar dimensions than the diameter of the cup holder 2×R2, and in the relation of R1˜R2.", "The present invention provides a novel method and apparatus that allow connecting any shaped article (e.g. dispenser) - 16 - to any shaped receiving article (e.g. cup holder) - 12 - through a connector - 18 - that is integrated within a wall of said first article which can be released into a three-dimensional arrangement - 20 - suitable for holding all articles.", "It is also obvious to those skilled in the art that the present invention also has several benefits during the manufacturing as the connector can be designed and fabricated during the conventional processing steps of conventional packaging manufacturing conditions.", "The arrangement - 20 - can comprise at least one component that can fold in a spatial configuration such as three-dimensional means that can interact, for example, through a mechanical force (e.g. friction, adhesion) or an electromagnetic force or field gradient in the case of an active actuation (e.g. electromagnet) that can be generated when a power source could be connected between the said articles.", "For example, the arrangement can allow versatile adjustment either through a constant or a variable physical interaction between said a dispenser -A- and a cup holder - 12 - suitable for connecting articles that can be dislike in shape, geometry, materials composition or any physico-chemical properties that may be of relevance to the intrinsic nature of the individual articles.", "The present invention provides capacity of engaging connecting articles in different relationships, such as A≠R2 or for example in the case of a second article such as a cup holder with dimensions A>D2>D3, as it is illustrated in FIG. 1C .", "Note that the article - 16 - preferably will comprise an opening means - 22 - on one of its walls for dispensing the content of said article (e.g. a tissue sheet).", "[0026] FIG. 2 (A,B,C,D) illustrate examples of a multitude of geometrical and spatial designs and configurations with 3-D and top view illustrations of a preferred embodiment of a tissue box - 16 - and its connector arrangement - 18 - and components - 20 that can be arranged in a symmetrical pattern (e.g. FIG. 2 A,B,C), such as a clover motif (e.g. FIG. 2B ) or in asymmetrical pattern (e.g. FIG. 2D ) which may also contain sub-components 24 - 30 suitable to assist individually or in combination during the mechanism of connecting said box to said holder.", "For example, a sub-component can be a curve line defining a random pattern connector that can be pliable, or including pillar - 26 -, groove - 28 , rod - 30 - or any other combination of shaped sub-component such as anchor-like object - 32 -.", "Now attention is directed towards FIG. 3 showing a preferred embodiment of a tissue box - 40 - with a dispensing opening - 42 - onto one of its walls (e.g. top wall) and a pliable pattern comprising a connector that can be comprised of at least a part - 44 - and a supporting part - 46 -.", "FIG. 3 a , shows a top view of an unfolded two dimensional diagram of one of the preferred embodiment of the present invention, while FIG. 3 b illustrates a three-dimensional view of the invention.", "FIG. 3 c illustrates a sequence of steps for the spatial deployment of the connector of one preferred embodiment of the present invention.", "For example, the wall - 48 - of the tissue box will represent the bottom surface which can then be inserted in a holder that can allow securing a typical cubic and commercially available tissue box into the cup holder of a car so that a driver or passenger could access the content of the box and dispense tissue safely and accurately while the vehicle may be in motion.", "FIG. 4 illustrates another preferred embodiment placing a first cubic article - 50 - with its unfolded connector - 52 - inserted into a second article of dissimilar shape, for example a cylindrical cup holder, wherein a configuration can comprise a connector surface is directly engaged in a frictional force with the walls of the cup holder to apply pressure and provide safe attachment of said box and allowing active delivery of the content - 56 - without significantly unlocking the position of both articles.", "A configuration using discrete part thereof - 58 - of the connector - 52 - for positioning and locking the first article in close proximity of said second article by exerting contact and possibly pressure of parts - 58 - with the wall of the holder - 54 - is also illustrated in the FIG. 4 .", "[0027] While the figures and descriptions herein have been described in conjunction with specific embodiments, many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description.", "Changes in form, as well as substitution of equivalents, are contemplated as circumstances may suggest or render expedient." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a 35 USC 371 application of PCT/DE 02/03318 filed on Sep. 6, 2002. BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a fuel injection system for an internal combustion engine with direct injection, having a fuel injection device which can inject the fuel directly into a combustion chamber of the engine and a valve element which borders on a work chamber, and the position of the valve element depends on the pressure in the work chamber; having a pressure booster piston, which on one side borders on a control chamber and on the other side borders on a high-pressure chamber; and having a fuel supply, which can subject the control chamber to various pressures. 2. Description of the Prior Art One fuel injection system, known from German Patent Disclosure DE 199 45 785 A1, includes a fuel pump which has a high-pressure and a low-pressure outlet. The highpressure outlet communicates with a control chamber of a pressure booster device. A high-pressure chamber of the pressure booster device communicates via a check valve with the low-pressure outlet of the fuel pump. A high-pressure line leads from the high-pressure chamber to a work chamber of a fuel injection device, by way of which the pressure is transmitted from the high-pressure chamber into this work chamber. Depending on the pressure in the high-pressure chamber or in the work chamber, a valve element of the fuel injection device is moved from a closed position to an opened position, or vice versa. The advantage of a pressure booster device or a hydraulic booster device is primarily that a relatively simple fuel pump can be used, yet the fuel can still be injected at very high pressure into a combustion chamber of the engine. This is important for the sake of favorable emissions performance of the engine. From German Patent Disclosure DE 197 38 804 A1, a fuel injection system with a hydraulic booster device is likewise known. In it as well, the hydraulic booster device communicates with the fuel injection device via a high-pressure line. The object of the present invention is to further develop a fuel injection system of the type defined at the outset such that when it is used, the emissions performance of the engine is even better, and as little energy as possible is needed to operate the fuel injection system. The temperature of the fuel injection device in operation should also be as low as possible. This object is attained, in a fuel injection system of the type defined at the outset, in that the pressure booster piston is integrated with the fuel injection device, and the high-pressure chamber is integrated with the work chamber. SUMMARY OF THE INVENTION By integrating the pressure booster piston with the fuel injection device and the high-pressure chamber with the work chamber, a separate high-pressure line that leads from the pressure booster device to the fuel injection device is no longer necessary. As a result, the total volume to be compressed by the pressure booster device is reduced. This accelerates the motion of the pressure booster piston in both directions, and as a consequence speeds up the buildup (and reduction) of the pressure in the high-pressure chamber. This in turn prevents fuel, for instance at the onset or end of an injection, from reaching the combustion chamber of the engine with only little pressure or little impetus. The high impetus with which the fuel in the fuel injection system of the invention is injected leads to an improvement in the emissions performance of the engine. The energy to be brought to bear to operate the fuel injection system of the invention is also relatively slight, since because of the reduced volume that has to be compressed and expanded, only slight energy losses occur upon this compression and expansion. This also lessens the unwanted heating of the fuel injection device during its operation, since less entropy occurs in the compression and decompression work of the fuel. The pumping volume that has to be furnished for compressing the fuel in the high-pressure chamber is also less, so that a fuel supply with less capacity can be provided. The loads on all the components used in the fuel injection system are also reduced, since the high pressure is now applied to essentially only in the combined high-pressure and work chamber. Less-expensive components can therefore be used for producing the fuel injection system of the invention. In a first refinement, the pressure booster piston is disposed coaxially to the valve element. A fuel injection device of this kind is relatively compact, above all in the radial direction. In a refinement of this, the valve element is guided in the pressure booster piston. This additionally has the advantage that the axial dimensions of the fuel injection device can also be kept comparatively slight. Moreover, because of the pressure booster piston, guidance for the valve element is created, so that the valve element cooperates very precisely with a valve seat assigned to it. It is also advantageous if a longitudinal bore, by which the high-pressure chamber is supplied with fuel, is present in the valve element. This leads to a further reduction in the radial size of the fuel injection device that is used in the fuel injection system of the invention. In an especially preferred feature of the fuel injection system of the invention, a check valve which opens toward the high-pressure chamber is present between the longitudinal bore in the valve element and the high-pressure chamber. Such a check valve is very simple in structure and assures that the highpressure chamber is reliably disconnected from the fuel supply during a compression. This is highly advantageous for the function of the pressure booster. The disposition near the high-pressure chamber reduces the loads on the longitudinal bore in operation, so that an inexpensive material can be selected for the valve element. The longitudinal bore in the valve element can communicate with a low-pressure fuel supply. Thus whenever a high pressure does not prevail in the high-pressure chamber, the high-pressure chamber can be supplied with fuel that is available at a uniform, low pressure. Filling of the high-pressure chamber with fuel thus takes place uniformly and securely, and the loads on the longitudinal bore and thus on the valve element are kept slight. As an alternative to this, it is possible that the longitudinal bore in the valve element communicates with a high-pressure fuel supply, which can also subject the control chamber to various pressures. In this case, a separate low-pressure fuel supply can be dispensed with. This reduces the costs of the fuel injection system of the invention. Moreover, incorporating this system into an internal combustion engine is facilitated, since it is no longer necessary to manipulate a separate low-pressure line. For concrete realization of this, it is proposed that the control chamber coaxially surrounds the valve element, and that the longitudinal bore in the valve element communicates with the control chamber via a radially extending opening. This is space-saving and can be produced economically. In a further variant, the pressure booster piston is braced via a spring on a nozzle body of the fuel injection device. The effect of this is that the pressure booster piston is reliably urged into its outset position. A hollow chamber, which is present between the pressure booster piston and the nozzle body and is variable in volume upon a motion of the pressure booster piston, preferably communicates with a leak fluid outlet via a check valve, and the check valve opens toward the leak fluid outlet. The spring that acts on the pressure booster piston can for instance be accommodated in such a hollow chamber. By means of the leak fluid outlet with the check valve, upon the first stroke of the pressure booster piston, any fuel present in the hollow chamber is pumped toward the leak fluid outlet. In all the further strokes of the pressure booster piston, then only the remaining fuel vapor in the hollow chamber has to be compressed, and any leakage that may occur between injections is pumped to a leakage removal line. As a result, pressure fluctuations in the low-pressure loop are avoided, and the energy expenditure needed to operate the fuel injection system of the invention is reduced still further. It is also possible for the control chamber to be capable of being made to communicate via a check valve with a low-pressure fuel supply, where the check valve opens toward the control chamber. If in iperation the minimal pressure in the control chamber is below the pressure furnished by the low-pressure fuel supply, then when the minimal pressure in the control chamber is reached, the check valve is opened, and a slight quantity of fuel flows from the low-pressure fuel supply into the control chamber. This is based on the following thought: The fluid located in the control chamber is constantly being compressed and decompressed again by the high-pressure fuel supply. This creates entropy or heat, which causes heating of the entire fuel injection device. This can impair the functioning of the fuel injection device. Because in the refinement proposed here “fresh” and thus cool fuel constantly reaches the control chamber from the low-pressure fuel supply, the temperature of the fuel located in the control chamber is lowered, and the overall heating of the fuel injection device in operation of the fuel injection system of the invention is reduced. BRIEF DESCRIPTION OF THE DRAWINGS Preferred exemplary embodiments of the present invention are described in detail herein below, in conjunction with the accompanying drawings, in which: FIG. 1 is a basic sketch of a first exemplary embodiment of a fuel injection system for an internal combustion engine with a fuel injection device; FIG. 2 , a fragmentary section through the fuel injection device of FIG. 1 , with a pressure booster piston in a first position; FIG. 3 , a view similar to FIG. 2 of a region of the fuel injection device of FIG. 1 with the pressure booster piston in a second position; FIG. 4 , is a basic sketch similar to FIG. 1 of a second exemplary embodiment of a fuel injection system for an internal combustion engine with a fuel injection device; FIG. 5 , a fragmentary section through the fuel injection device of FIG. 4 , with a pressure booster piston in a first position; and FIG. 6 , a view similar to FIG. 5 of a region of the fuel injection device of FIG. 4 with the pressure booster piston in a second position. DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 , a fuel injection system according to the invention is identified overall by reference numeral 10 and includes a fuel tank 12 , from which a fuel pump 14 pumps the fuel to a fuel injection device 16 . The fuel injection device is an injector that injects the fuel directly into a combustion chamber 18 of an internal combustion engine (not further shown). The fuel pump 14 includes a control pressure outlet 20 and a low-pressure outlet 22 . A control pressure line 24 is connected to the control pressure outlet 20 . A control valve 26 is disposed in the control pressure line. From the control valve 26 , a diversion line 28 leads back to the fuel tank 12 . The control pressure line 24 leads to a control pressure connection 30 on the fuel injection device 16 . The control valve 26 should be switched such that in one switching position, the control pressure outlet 20 of the fuel pump 14 communicates with the control pressure connection 30 of the fuel injection device 16 , while conversely in another switching position of the control valve 26 , the control pressure connection 30 communicates with the fuel tank 12 via the diversion line 28 . From the low-pressure outlet 22 of the fuel pump 14 , a low-pressure line 32 leads to a low-pressure connection 34 on the fuel injection device 16 . A leak fluid line 38 leads from a leak fluid outlet 36 of the fuel injection device 16 back to the fuel tank 12 . The precise structure of the fuel injection device 16 can be seen from FIGS. 2 and 3 where it is seen that the fuel injection device 16 includes a nozzle body 40 , which comprises a lower part 42 , in terms of FIGS. 2 and 3 , and an upper part 44 which is braced by a nozzle lock nut 46 against a connection part 48 . The upper part 44 of the nozzle body 40 is sleevelike. The lower part 42 of the nozzle body 40 has a stepped blind bore 50 . On the lower end, in terms of FIG. 2 , of the lower part 42 of the nozzle body 40 , outlet openings 52 lead to the outside from the blind bore 50 . All the parts described thus far are furthermore rotationally symmetrical parts of circular-cylindrical cross section. In the blind bore 50 of the lower part 42 of the nozzle body 40 and in the sleevelike upper part 44 of the nozzle body 40 , a pressure booster piston 54 is received axially displaceably with sliding play. This part likewise comprises an upper part 56 and a lower part 58 , in terms of FIG. 2 . An annular collar 60 is formed onto the upper end of the lower part 58 of the pressure booster piston 54 . A compression spring 62 is braced on the annular collar, and its other end rests on the lower part 42 of the nozzle body 40 . The compression spring 62 urges the lower part 58 of the pressure booster piston 54 , with the annular collar 60 , against a shoulder 64 in the upper part 44 of the nozzle body 40 . The compression spring 62 is received in an annular chamber 65 . A lower axial end face 66 , that is, lower in terms of FIG. 2 , on the lower part 58 of the pressure booster piston 54 is smaller overall than an upper axial end face 68 on the upper part 56 of the pressure booster piston 54 . The pressure booster piston 54 is penetrated by a recess. A portion of a valve needle 70 is guided in the recess, and this valve needle cooperates with a valve seat (not identified by reference numeral) on the lower end of the blind bore 50 , in the region of the outlet openings 52 . The valve needle 70 and the pressure booster piston 54 are thus disposed coaxially to one another. The valve needle 70 extends through the pressure booster piston 54 , upward in terms of FIG. 2 , into a blind bore 74 in the connection part 48 of the fuel injection device 16 . Between the upper end, in terms of FIG. 2 , of the valve needle 70 and the end of the blind 74 , a compression spring 72 is fastened that urges the valve needle 70 against the valve seat in the region of the outlet openings 52 , or in other words in the closing direction. The axial length of the lower part 58 of the pressure booster piston 54 is dimensioned such that the pressure booster piston 54 , in the upper outset position shown in FIG. 2 , ends at the bottom before a cross-sectional narrowing (not identified by reference numeral) of the stepped blind bore 50 in the nozzle body 40 . An annular high-pressure chamber 76 is formed between the valve needle 70 , the lower end face 66 of the pressure booster piston 54 , and the wall of the stepped blind bore 50 in the nozzle body 40 . The valve needle 70 extends through the high-pressure chamber 76 . In the region of the high-pressure chamber 76 , there is a cross-sectional enlargement on the valve needle 70 that forms a pressure face 78 , whose force resultant opposes the pressure force exerted by the compression spring 72 , or in other words points in the opening direction of the valve needle 70 . The space surrounding the pressure face is called the work chamber 79 . It coincides with the high-pressure chamber 76 . From the high-pressure chamber 76 , an annular chamber (not identified by reference numeral), which is formed between the valve needle 70 and the lower region of the blind bore 50 in the nozzle body 40 , extends as far as the valve seat, that is, the outlet openings 52 . In the valve needle 70 , a radial bore 82 extends into the high-pressure chamber 76 from a spring chamber 80 that is located in the valve needle 70 in the region of the high-pressure chamber 76 . A spring-loaded check valve 84 that opens toward the spring chamber 80 is disposed in the spring chamber 80 . From the check valve 84 , a low-pressure conduit 86 that is coaxial with the longitudinal axis of the valve needle 70 extends in the valve needle 70 as far as the upper end, in terms of FIG. 2 , of the valve needle 70 , where it discharges into the blind bore 74 in the connection part 48 . The blind bore 74 communicates, via a radial bore 88 in the wall of the connection part 48 , with an annular conduit 90 in a connecting part 92 . The connecting part, via the low-pressure connection 34 , establishes a communication with the low-pressure line 32 . From the control pressure connection 30 , which in terms of FIG. 2 is located at the upper end of the connection part 48 , an overall eccentric control conduit 94 leads to a control chamber 96 . This control chamber 96 is formed as an annular chamber between the upper axial end face 68 of the pressure booster piston 54 , the outer jacket face of the valve needle 70 , and the connecting part 48 of the nozzle body 40 and is thus disposed coaxially with the valve needle 70 . Via a springloaded check valve 98 that opens toward the control chamber 96 , the control chamber communicates with a scavenging conduit 100 that discharges into the radial bore 88 in the connection part 48 . In FIG. 3 , the lower part of the fuel injection device 16 is shown. The view in FIG. 3 is rotated by 90° about the longitudinal axis of the fuel injection device 16 , compared to FIG. 2 . Moreover, in FIG. 3 the pressure booster piston 54 is in its lower end position, while conversely in FIG. 2 it is in its upper outset position. As can be seen from FIG. 3 , from the boundary region between the annular collar 60 on the lower part 58 of the pressure booster piston 54 and the shoulder 64 of the upper part 44 of the nozzle body 40 , a longitudinal groove 102 leads between the nozzle lock nut 46 and the upper part 44 of the nozzle body 40 . It leads to a spring-loaded check valve 104 . The check valve blocks in the direction toward the longitudinal groove 102 . From the check valve 104 , a conduit not shown in the drawing leads to the leak fluid outlet 36 . The fuel injection system 10 shown in FIGS. 1–3 functions as follows: Before an injection of fuel into the combustion chamber 18 by the fuel injection device 16 , the high-pressure chamber 76 is filled with fuel. To that end, fuel is pumped from the low-pressure outlet 22 of the fuel pump 14 to the low-pressure connection 34 of the fuel injection device 16 . From there, the fuel reaches the high-pressure chamber 76 , via the low-pressure conduit 86 in the valve needle 70 , the check valve 84 , the spring chamber 80 , and the conduit 82 . Once the pressure in the high-pressure chamber 76 is approximately equivalent to the pressure at the low-pressure outlet 22 of the fuel pump 14 , the check valve 84 closes. The control valve 26 is at first switched such that the control pressure connection 30 of the fuel injection device 16 communicates with the fuel tank 12 . The control chamber 96 is accordingly extensively pressureless, and the pressure booster piston 54 is in the upper outset position shown in FIG. 2 . For performing an injection, the control valve 26 is switched such that the control pressure connection 30 communicates with the control pressure outlet 20 of the fuel pump 14 . The corresponding pressure now prevails, via the control conduit 94 , in the control chamber 96 as well. The pressure at the control pressure outlet 20 of the fuel pump 14 is considerably higher than the pressure at the low-pressure outlet 22 . For this reason, and because of the ratios in the surface areas of the axial end faces 66 and 68 of the pressure booster piston 54 , the result at the pressure booster piston 54 is a force oriented toward the high-pressure chamber 76 , so that the pressure booster piston 54 moves in the direction of the high-pressure chamber 76 . As a result, the fuel present in the high-pressure chamber 76 is compressed, and a very high pressure in the high-pressure chamber 76 is generated. In the lower end position of the pressure booster piston 54 , shown in FIG. 3 , the pressure in the high-pressure chamber 76 can be as high as approximately 1800 bar. Because of the high pressure in the high-pressure chamber 76 , that is, in the work chamber 79 , the result at the pressure face 78 of the valve needle 70 is a force oriented in the opening direction of the valve needle 70 , counter to the direction of action by the compression spring 72 . Because of this force, the valve needle 70 is lifted from the valve seat, and as a result the outlet openings 52 are made to communicate with the high-pressure chamber 76 . Thus the fuel reaches the combustion chamber 18 from the outlet openings 52 at very high pressure. If the injection is to be terminated, the control valve 26 is switched against in such a way that the control pressure connection 30 of the fuel injection device 16 communicates with the fuel tank 12 . This causes a sudden relief of the control chamber 96 . By means of the compression spring 62 , the pressure booster piston 54 is pressed upward again in terms of FIGS. 2 and 3 . As a result, the pressure in the high-pressure chamber 76 , that is, the work chamber 79 , also drops, so that the valve needle 70 closes. Once the pressure in the high-pressure chamber 76 has dropped enough, the check valve 84 opens. Replenishing fuel can then flow into the high-pressure chamber 76 through the low-pressure conduit 86 . As a result of the sudden pressure drop in the control chamber 96 , a relief pressure wave is generated. This causes the check valve 98 to open briefly, and cold fuel from the scavenging conduit 100 reaches the control chamber 96 . This has the advantage that the temperature increase of the fuel enclosed in the control chamber 96 , caused by the repeated compression and decompression, is compensated for by the delivery of cool fuel, and thus the temperature increase of the entire fuel injection device 16 in operation can be kept within certain limits. As a result of certain leaks between the parts that move relative to one another, fuel also reaches the space 65 between the lower part 42 of the nozzle body 40 and the lower part 58 of the pressure booster piston 54 , in which the compression spring 62 is disposed. When upon an injection the pressure booster piston 54 moves downward in terms of FIGS. 2 and 3 , the volume of this space also decreases. Fuel present in it is therefore carried away to the leak fluid outlet 36 via the longitudinal groove 102 and the check valve 104 . In the ensuing injections or reciprocating motions of the pressure booster piston 54 , essentially no further fuel is pumped out of the space to the leak fluid outlet 36 . Instead, fuel vapor forms in this space, and this vapor is compressed during the reciprocating motions of the pressure booster piston 54 from vapor pressure to approximately ambient pressure. As a result, pressure fluctuations in the low-pressure loop are avoided. In FIGS. 4–6 , a second exemplary embodiment of a fuel injection system 10 is shown. Parts, elements and regions that have equivalent functions to parts, elements and regions of the exemplary embodiment shown in FIGS. 1–3 are identified by the same reference numerals. They are not described here again in detail. One essential difference between the fuel injection system 10 shown in FIG. 4 and the above system is that the fuel pump 14 now has only a control pressure outlet 20 but no low-pressure outlet. Correspondingly, the fuel injection device 16 has only a control pressure connection 30 and a leak fluid outlet 36 . Consequently, in FIG. 5 , there is no low-pressure outlet. In the fuel injection device 16 shown in FIGS. 5 and 6 , there is no check valve between the longitudinal groove 102 and the leak fluid outlet 36 . Instead, the longitudinal groove 102 extends via a leakage conduit 106 directly to the leak fluid outlet 36 . The leak fluid outlet is furthermore in communication, via a radial bore 108 in the wall of the connection part 48 , with the interior of the blind bore 74 in the connection part 48 . Supplying the high-pressure chamber 76 with fuel is effected in the fuel injection device 16 shown in FIGS. 5 and 6 via the control chamber 96 . To that end, there is a radial inlet bore 110 in the wall of the valve needle 70 , at the level of the control chamber 96 . In addition, the conduit 86 in the valve needle 70 extends from the check valve 84 only to the level of the control chamber 96 . The advantage of this exemplary embodiment is that a low-pressure system (low-pressure outlet at the fuel pump, low-pressure line, low-pressure connection at the fuel injection device, etc.) can be dispensed with. The high-pressure chamber 76 , as already noted above, is the chamber in which an enclosed fluid is compressed by the pressure booster piston 54 , and a very high pressure is thus generated. The work chamber 79 is the chamber in which, by a pressure change at the pressure face 78 of the valve needle 70 , a force is generated that leads to a motion of the valve needle 70 . In both fuel injection devices 16 described above, the high-pressure chamber 76 of the pressure booster piston 54 is integrated with the work chamber 79 of the valve needle 70 . The two chambers accordingly coincide. Thus upon an injection through the fuel injection device 16 , only a comparatively small total volume is compressed, which reduces unwanted effects of elasticity of the fuel enclosed in the high-pressure chamber 76 . The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.
A fuel injection system for an internal combustion engine with direct injection includes a fuel injection device which can inject the fuel directly into a combustion chamber of the engine has a valve element bordering on a work chamber, and the position of the valve element depends on the pressure in the work chamber. A pressure booster piston borders on a control chamber on one side and on a high-pressure chamber on the other. A fuel supply can subject the control chamber to various pressures. The pressure booster piston is integrated with the fuel injection device and that the high-pressure chamber is integrated with the work chamber.
Identify and summarize the most critical features from the given passage.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application is a 35 USC 371 application of PCT/DE 02/03318 filed on Sep. 6, 2002.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The invention relates to a fuel injection system for an internal combustion engine with direct injection, having a fuel injection device which can inject the fuel directly into a combustion chamber of the engine and a valve element which borders on a work chamber, and the position of the valve element depends on the pressure in the work chamber;", "having a pressure booster piston, which on one side borders on a control chamber and on the other side borders on a high-pressure chamber;", "and having a fuel supply, which can subject the control chamber to various pressures.", "Description of the Prior Art One fuel injection system, known from German Patent Disclosure DE 199 45 785 A1, includes a fuel pump which has a high-pressure and a low-pressure outlet.", "The highpressure outlet communicates with a control chamber of a pressure booster device.", "A high-pressure chamber of the pressure booster device communicates via a check valve with the low-pressure outlet of the fuel pump.", "A high-pressure line leads from the high-pressure chamber to a work chamber of a fuel injection device, by way of which the pressure is transmitted from the high-pressure chamber into this work chamber.", "Depending on the pressure in the high-pressure chamber or in the work chamber, a valve element of the fuel injection device is moved from a closed position to an opened position, or vice versa.", "The advantage of a pressure booster device or a hydraulic booster device is primarily that a relatively simple fuel pump can be used, yet the fuel can still be injected at very high pressure into a combustion chamber of the engine.", "This is important for the sake of favorable emissions performance of the engine.", "From German Patent Disclosure DE 197 38 804 A1, a fuel injection system with a hydraulic booster device is likewise known.", "In it as well, the hydraulic booster device communicates with the fuel injection device via a high-pressure line.", "The object of the present invention is to further develop a fuel injection system of the type defined at the outset such that when it is used, the emissions performance of the engine is even better, and as little energy as possible is needed to operate the fuel injection system.", "The temperature of the fuel injection device in operation should also be as low as possible.", "This object is attained, in a fuel injection system of the type defined at the outset, in that the pressure booster piston is integrated with the fuel injection device, and the high-pressure chamber is integrated with the work chamber.", "SUMMARY OF THE INVENTION By integrating the pressure booster piston with the fuel injection device and the high-pressure chamber with the work chamber, a separate high-pressure line that leads from the pressure booster device to the fuel injection device is no longer necessary.", "As a result, the total volume to be compressed by the pressure booster device is reduced.", "This accelerates the motion of the pressure booster piston in both directions, and as a consequence speeds up the buildup (and reduction) of the pressure in the high-pressure chamber.", "This in turn prevents fuel, for instance at the onset or end of an injection, from reaching the combustion chamber of the engine with only little pressure or little impetus.", "The high impetus with which the fuel in the fuel injection system of the invention is injected leads to an improvement in the emissions performance of the engine.", "The energy to be brought to bear to operate the fuel injection system of the invention is also relatively slight, since because of the reduced volume that has to be compressed and expanded, only slight energy losses occur upon this compression and expansion.", "This also lessens the unwanted heating of the fuel injection device during its operation, since less entropy occurs in the compression and decompression work of the fuel.", "The pumping volume that has to be furnished for compressing the fuel in the high-pressure chamber is also less, so that a fuel supply with less capacity can be provided.", "The loads on all the components used in the fuel injection system are also reduced, since the high pressure is now applied to essentially only in the combined high-pressure and work chamber.", "Less-expensive components can therefore be used for producing the fuel injection system of the invention.", "In a first refinement, the pressure booster piston is disposed coaxially to the valve element.", "A fuel injection device of this kind is relatively compact, above all in the radial direction.", "In a refinement of this, the valve element is guided in the pressure booster piston.", "This additionally has the advantage that the axial dimensions of the fuel injection device can also be kept comparatively slight.", "Moreover, because of the pressure booster piston, guidance for the valve element is created, so that the valve element cooperates very precisely with a valve seat assigned to it.", "It is also advantageous if a longitudinal bore, by which the high-pressure chamber is supplied with fuel, is present in the valve element.", "This leads to a further reduction in the radial size of the fuel injection device that is used in the fuel injection system of the invention.", "In an especially preferred feature of the fuel injection system of the invention, a check valve which opens toward the high-pressure chamber is present between the longitudinal bore in the valve element and the high-pressure chamber.", "Such a check valve is very simple in structure and assures that the highpressure chamber is reliably disconnected from the fuel supply during a compression.", "This is highly advantageous for the function of the pressure booster.", "The disposition near the high-pressure chamber reduces the loads on the longitudinal bore in operation, so that an inexpensive material can be selected for the valve element.", "The longitudinal bore in the valve element can communicate with a low-pressure fuel supply.", "Thus whenever a high pressure does not prevail in the high-pressure chamber, the high-pressure chamber can be supplied with fuel that is available at a uniform, low pressure.", "Filling of the high-pressure chamber with fuel thus takes place uniformly and securely, and the loads on the longitudinal bore and thus on the valve element are kept slight.", "As an alternative to this, it is possible that the longitudinal bore in the valve element communicates with a high-pressure fuel supply, which can also subject the control chamber to various pressures.", "In this case, a separate low-pressure fuel supply can be dispensed with.", "This reduces the costs of the fuel injection system of the invention.", "Moreover, incorporating this system into an internal combustion engine is facilitated, since it is no longer necessary to manipulate a separate low-pressure line.", "For concrete realization of this, it is proposed that the control chamber coaxially surrounds the valve element, and that the longitudinal bore in the valve element communicates with the control chamber via a radially extending opening.", "This is space-saving and can be produced economically.", "In a further variant, the pressure booster piston is braced via a spring on a nozzle body of the fuel injection device.", "The effect of this is that the pressure booster piston is reliably urged into its outset position.", "A hollow chamber, which is present between the pressure booster piston and the nozzle body and is variable in volume upon a motion of the pressure booster piston, preferably communicates with a leak fluid outlet via a check valve, and the check valve opens toward the leak fluid outlet.", "The spring that acts on the pressure booster piston can for instance be accommodated in such a hollow chamber.", "By means of the leak fluid outlet with the check valve, upon the first stroke of the pressure booster piston, any fuel present in the hollow chamber is pumped toward the leak fluid outlet.", "In all the further strokes of the pressure booster piston, then only the remaining fuel vapor in the hollow chamber has to be compressed, and any leakage that may occur between injections is pumped to a leakage removal line.", "As a result, pressure fluctuations in the low-pressure loop are avoided, and the energy expenditure needed to operate the fuel injection system of the invention is reduced still further.", "It is also possible for the control chamber to be capable of being made to communicate via a check valve with a low-pressure fuel supply, where the check valve opens toward the control chamber.", "If in iperation the minimal pressure in the control chamber is below the pressure furnished by the low-pressure fuel supply, then when the minimal pressure in the control chamber is reached, the check valve is opened, and a slight quantity of fuel flows from the low-pressure fuel supply into the control chamber.", "This is based on the following thought: The fluid located in the control chamber is constantly being compressed and decompressed again by the high-pressure fuel supply.", "This creates entropy or heat, which causes heating of the entire fuel injection device.", "This can impair the functioning of the fuel injection device.", "Because in the refinement proposed here “fresh”", "and thus cool fuel constantly reaches the control chamber from the low-pressure fuel supply, the temperature of the fuel located in the control chamber is lowered, and the overall heating of the fuel injection device in operation of the fuel injection system of the invention is reduced.", "BRIEF DESCRIPTION OF THE DRAWINGS Preferred exemplary embodiments of the present invention are described in detail herein below, in conjunction with the accompanying drawings, in which: FIG. 1 is a basic sketch of a first exemplary embodiment of a fuel injection system for an internal combustion engine with a fuel injection device;", "FIG. 2 , a fragmentary section through the fuel injection device of FIG. 1 , with a pressure booster piston in a first position;", "FIG. 3 , a view similar to FIG. 2 of a region of the fuel injection device of FIG. 1 with the pressure booster piston in a second position;", "FIG. 4 , is a basic sketch similar to FIG. 1 of a second exemplary embodiment of a fuel injection system for an internal combustion engine with a fuel injection device;", "FIG. 5 , a fragmentary section through the fuel injection device of FIG. 4 , with a pressure booster piston in a first position;", "and FIG. 6 , a view similar to FIG. 5 of a region of the fuel injection device of FIG. 4 with the pressure booster piston in a second position.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 , a fuel injection system according to the invention is identified overall by reference numeral 10 and includes a fuel tank 12 , from which a fuel pump 14 pumps the fuel to a fuel injection device 16 .", "The fuel injection device is an injector that injects the fuel directly into a combustion chamber 18 of an internal combustion engine (not further shown).", "The fuel pump 14 includes a control pressure outlet 20 and a low-pressure outlet 22 .", "A control pressure line 24 is connected to the control pressure outlet 20 .", "A control valve 26 is disposed in the control pressure line.", "From the control valve 26 , a diversion line 28 leads back to the fuel tank 12 .", "The control pressure line 24 leads to a control pressure connection 30 on the fuel injection device 16 .", "The control valve 26 should be switched such that in one switching position, the control pressure outlet 20 of the fuel pump 14 communicates with the control pressure connection 30 of the fuel injection device 16 , while conversely in another switching position of the control valve 26 , the control pressure connection 30 communicates with the fuel tank 12 via the diversion line 28 .", "From the low-pressure outlet 22 of the fuel pump 14 , a low-pressure line 32 leads to a low-pressure connection 34 on the fuel injection device 16 .", "A leak fluid line 38 leads from a leak fluid outlet 36 of the fuel injection device 16 back to the fuel tank 12 .", "The precise structure of the fuel injection device 16 can be seen from FIGS. 2 and 3 where it is seen that the fuel injection device 16 includes a nozzle body 40 , which comprises a lower part 42 , in terms of FIGS. 2 and 3 , and an upper part 44 which is braced by a nozzle lock nut 46 against a connection part 48 .", "The upper part 44 of the nozzle body 40 is sleevelike.", "The lower part 42 of the nozzle body 40 has a stepped blind bore 50 .", "On the lower end, in terms of FIG. 2 , of the lower part 42 of the nozzle body 40 , outlet openings 52 lead to the outside from the blind bore 50 .", "All the parts described thus far are furthermore rotationally symmetrical parts of circular-cylindrical cross section.", "In the blind bore 50 of the lower part 42 of the nozzle body 40 and in the sleevelike upper part 44 of the nozzle body 40 , a pressure booster piston 54 is received axially displaceably with sliding play.", "This part likewise comprises an upper part 56 and a lower part 58 , in terms of FIG. 2 .", "An annular collar 60 is formed onto the upper end of the lower part 58 of the pressure booster piston 54 .", "A compression spring 62 is braced on the annular collar, and its other end rests on the lower part 42 of the nozzle body 40 .", "The compression spring 62 urges the lower part 58 of the pressure booster piston 54 , with the annular collar 60 , against a shoulder 64 in the upper part 44 of the nozzle body 40 .", "The compression spring 62 is received in an annular chamber 65 .", "A lower axial end face 66 , that is, lower in terms of FIG. 2 , on the lower part 58 of the pressure booster piston 54 is smaller overall than an upper axial end face 68 on the upper part 56 of the pressure booster piston 54 .", "The pressure booster piston 54 is penetrated by a recess.", "A portion of a valve needle 70 is guided in the recess, and this valve needle cooperates with a valve seat (not identified by reference numeral) on the lower end of the blind bore 50 , in the region of the outlet openings 52 .", "The valve needle 70 and the pressure booster piston 54 are thus disposed coaxially to one another.", "The valve needle 70 extends through the pressure booster piston 54 , upward in terms of FIG. 2 , into a blind bore 74 in the connection part 48 of the fuel injection device 16 .", "Between the upper end, in terms of FIG. 2 , of the valve needle 70 and the end of the blind 74 , a compression spring 72 is fastened that urges the valve needle 70 against the valve seat in the region of the outlet openings 52 , or in other words in the closing direction.", "The axial length of the lower part 58 of the pressure booster piston 54 is dimensioned such that the pressure booster piston 54 , in the upper outset position shown in FIG. 2 , ends at the bottom before a cross-sectional narrowing (not identified by reference numeral) of the stepped blind bore 50 in the nozzle body 40 .", "An annular high-pressure chamber 76 is formed between the valve needle 70 , the lower end face 66 of the pressure booster piston 54 , and the wall of the stepped blind bore 50 in the nozzle body 40 .", "The valve needle 70 extends through the high-pressure chamber 76 .", "In the region of the high-pressure chamber 76 , there is a cross-sectional enlargement on the valve needle 70 that forms a pressure face 78 , whose force resultant opposes the pressure force exerted by the compression spring 72 , or in other words points in the opening direction of the valve needle 70 .", "The space surrounding the pressure face is called the work chamber 79 .", "It coincides with the high-pressure chamber 76 .", "From the high-pressure chamber 76 , an annular chamber (not identified by reference numeral), which is formed between the valve needle 70 and the lower region of the blind bore 50 in the nozzle body 40 , extends as far as the valve seat, that is, the outlet openings 52 .", "In the valve needle 70 , a radial bore 82 extends into the high-pressure chamber 76 from a spring chamber 80 that is located in the valve needle 70 in the region of the high-pressure chamber 76 .", "A spring-loaded check valve 84 that opens toward the spring chamber 80 is disposed in the spring chamber 80 .", "From the check valve 84 , a low-pressure conduit 86 that is coaxial with the longitudinal axis of the valve needle 70 extends in the valve needle 70 as far as the upper end, in terms of FIG. 2 , of the valve needle 70 , where it discharges into the blind bore 74 in the connection part 48 .", "The blind bore 74 communicates, via a radial bore 88 in the wall of the connection part 48 , with an annular conduit 90 in a connecting part 92 .", "The connecting part, via the low-pressure connection 34 , establishes a communication with the low-pressure line 32 .", "From the control pressure connection 30 , which in terms of FIG. 2 is located at the upper end of the connection part 48 , an overall eccentric control conduit 94 leads to a control chamber 96 .", "This control chamber 96 is formed as an annular chamber between the upper axial end face 68 of the pressure booster piston 54 , the outer jacket face of the valve needle 70 , and the connecting part 48 of the nozzle body 40 and is thus disposed coaxially with the valve needle 70 .", "Via a springloaded check valve 98 that opens toward the control chamber 96 , the control chamber communicates with a scavenging conduit 100 that discharges into the radial bore 88 in the connection part 48 .", "In FIG. 3 , the lower part of the fuel injection device 16 is shown.", "The view in FIG. 3 is rotated by 90° about the longitudinal axis of the fuel injection device 16 , compared to FIG. 2 .", "Moreover, in FIG. 3 the pressure booster piston 54 is in its lower end position, while conversely in FIG. 2 it is in its upper outset position.", "As can be seen from FIG. 3 , from the boundary region between the annular collar 60 on the lower part 58 of the pressure booster piston 54 and the shoulder 64 of the upper part 44 of the nozzle body 40 , a longitudinal groove 102 leads between the nozzle lock nut 46 and the upper part 44 of the nozzle body 40 .", "It leads to a spring-loaded check valve 104 .", "The check valve blocks in the direction toward the longitudinal groove 102 .", "From the check valve 104 , a conduit not shown in the drawing leads to the leak fluid outlet 36 .", "The fuel injection system 10 shown in FIGS. 1–3 functions as follows: Before an injection of fuel into the combustion chamber 18 by the fuel injection device 16 , the high-pressure chamber 76 is filled with fuel.", "To that end, fuel is pumped from the low-pressure outlet 22 of the fuel pump 14 to the low-pressure connection 34 of the fuel injection device 16 .", "From there, the fuel reaches the high-pressure chamber 76 , via the low-pressure conduit 86 in the valve needle 70 , the check valve 84 , the spring chamber 80 , and the conduit 82 .", "Once the pressure in the high-pressure chamber 76 is approximately equivalent to the pressure at the low-pressure outlet 22 of the fuel pump 14 , the check valve 84 closes.", "The control valve 26 is at first switched such that the control pressure connection 30 of the fuel injection device 16 communicates with the fuel tank 12 .", "The control chamber 96 is accordingly extensively pressureless, and the pressure booster piston 54 is in the upper outset position shown in FIG. 2 .", "For performing an injection, the control valve 26 is switched such that the control pressure connection 30 communicates with the control pressure outlet 20 of the fuel pump 14 .", "The corresponding pressure now prevails, via the control conduit 94 , in the control chamber 96 as well.", "The pressure at the control pressure outlet 20 of the fuel pump 14 is considerably higher than the pressure at the low-pressure outlet 22 .", "For this reason, and because of the ratios in the surface areas of the axial end faces 66 and 68 of the pressure booster piston 54 , the result at the pressure booster piston 54 is a force oriented toward the high-pressure chamber 76 , so that the pressure booster piston 54 moves in the direction of the high-pressure chamber 76 .", "As a result, the fuel present in the high-pressure chamber 76 is compressed, and a very high pressure in the high-pressure chamber 76 is generated.", "In the lower end position of the pressure booster piston 54 , shown in FIG. 3 , the pressure in the high-pressure chamber 76 can be as high as approximately 1800 bar.", "Because of the high pressure in the high-pressure chamber 76 , that is, in the work chamber 79 , the result at the pressure face 78 of the valve needle 70 is a force oriented in the opening direction of the valve needle 70 , counter to the direction of action by the compression spring 72 .", "Because of this force, the valve needle 70 is lifted from the valve seat, and as a result the outlet openings 52 are made to communicate with the high-pressure chamber 76 .", "Thus the fuel reaches the combustion chamber 18 from the outlet openings 52 at very high pressure.", "If the injection is to be terminated, the control valve 26 is switched against in such a way that the control pressure connection 30 of the fuel injection device 16 communicates with the fuel tank 12 .", "This causes a sudden relief of the control chamber 96 .", "By means of the compression spring 62 , the pressure booster piston 54 is pressed upward again in terms of FIGS. 2 and 3 .", "As a result, the pressure in the high-pressure chamber 76 , that is, the work chamber 79 , also drops, so that the valve needle 70 closes.", "Once the pressure in the high-pressure chamber 76 has dropped enough, the check valve 84 opens.", "Replenishing fuel can then flow into the high-pressure chamber 76 through the low-pressure conduit 86 .", "As a result of the sudden pressure drop in the control chamber 96 , a relief pressure wave is generated.", "This causes the check valve 98 to open briefly, and cold fuel from the scavenging conduit 100 reaches the control chamber 96 .", "This has the advantage that the temperature increase of the fuel enclosed in the control chamber 96 , caused by the repeated compression and decompression, is compensated for by the delivery of cool fuel, and thus the temperature increase of the entire fuel injection device 16 in operation can be kept within certain limits.", "As a result of certain leaks between the parts that move relative to one another, fuel also reaches the space 65 between the lower part 42 of the nozzle body 40 and the lower part 58 of the pressure booster piston 54 , in which the compression spring 62 is disposed.", "When upon an injection the pressure booster piston 54 moves downward in terms of FIGS. 2 and 3 , the volume of this space also decreases.", "Fuel present in it is therefore carried away to the leak fluid outlet 36 via the longitudinal groove 102 and the check valve 104 .", "In the ensuing injections or reciprocating motions of the pressure booster piston 54 , essentially no further fuel is pumped out of the space to the leak fluid outlet 36 .", "Instead, fuel vapor forms in this space, and this vapor is compressed during the reciprocating motions of the pressure booster piston 54 from vapor pressure to approximately ambient pressure.", "As a result, pressure fluctuations in the low-pressure loop are avoided.", "In FIGS. 4–6 , a second exemplary embodiment of a fuel injection system 10 is shown.", "Parts, elements and regions that have equivalent functions to parts, elements and regions of the exemplary embodiment shown in FIGS. 1–3 are identified by the same reference numerals.", "They are not described here again in detail.", "One essential difference between the fuel injection system 10 shown in FIG. 4 and the above system is that the fuel pump 14 now has only a control pressure outlet 20 but no low-pressure outlet.", "Correspondingly, the fuel injection device 16 has only a control pressure connection 30 and a leak fluid outlet 36 .", "Consequently, in FIG. 5 , there is no low-pressure outlet.", "In the fuel injection device 16 shown in FIGS. 5 and 6 , there is no check valve between the longitudinal groove 102 and the leak fluid outlet 36 .", "Instead, the longitudinal groove 102 extends via a leakage conduit 106 directly to the leak fluid outlet 36 .", "The leak fluid outlet is furthermore in communication, via a radial bore 108 in the wall of the connection part 48 , with the interior of the blind bore 74 in the connection part 48 .", "Supplying the high-pressure chamber 76 with fuel is effected in the fuel injection device 16 shown in FIGS. 5 and 6 via the control chamber 96 .", "To that end, there is a radial inlet bore 110 in the wall of the valve needle 70 , at the level of the control chamber 96 .", "In addition, the conduit 86 in the valve needle 70 extends from the check valve 84 only to the level of the control chamber 96 .", "The advantage of this exemplary embodiment is that a low-pressure system (low-pressure outlet at the fuel pump, low-pressure line, low-pressure connection at the fuel injection device, etc.) can be dispensed with.", "The high-pressure chamber 76 , as already noted above, is the chamber in which an enclosed fluid is compressed by the pressure booster piston 54 , and a very high pressure is thus generated.", "The work chamber 79 is the chamber in which, by a pressure change at the pressure face 78 of the valve needle 70 , a force is generated that leads to a motion of the valve needle 70 .", "In both fuel injection devices 16 described above, the high-pressure chamber 76 of the pressure booster piston 54 is integrated with the work chamber 79 of the valve needle 70 .", "The two chambers accordingly coincide.", "Thus upon an injection through the fuel injection device 16 , only a comparatively small total volume is compressed, which reduces unwanted effects of elasticity of the fuel enclosed in the high-pressure chamber 76 .", "The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims." ]
CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2008-247315 filed on Sep. 26, 2008, the disclosure of which is incorporated by reference herein. BACKGROUND [0002] 1. Field of the Invention [0003] The invention relates to a radiographic imaging table and, more particularly, to a radiographic imaging table used for imaging using a portable radiographic image detector. [0004] 2. Description of the Related Art [0005] Recently, a flat panel detector (FPD) that is constructed by disposing a radiation sensitive layer on a thin film transistor (TFT) active matrix substrate has been put to practical applications. The FPD can directly convert an X-ray into digital data. A portable radiographic image detecting device (hereinafter, referred to as an “ electronic cassette”) for generating image data indicating a radiographic image represented by a radiation penetrating a test object and being irradiated by using the FPD and storing the generated image data has been put to practical applications. [0006] Since the electronic cassette has good portability, a test object loaded on a stretcher or a bed can be imaged. In addition, since an imaged portion can be adjusted by changing a position of the electronic cassette, even an immobile patient as an example of the test object can be adaptively imaged. [0007] Such a portable electronic cassette is embedded with a memory for storing the image data of the captured images and a battery. The electronic cassette is inserted into a dedicated cassette stand so as to transmit the image data to an external device, that is, a console or to charge the embedded battery (for example, refer to Japanese Patent Application Laid-Open (JP-A) No. 2000-206636). However, every time the electronic cassette used with a bed is to be charged or the image data is to be transmitted, the electronic cassette needs to be moved to the cassette stand. Particularly, there is great inconvenience in a case where the bed and the cassette stand are separated from each other over a long distance. [0008] Therefore, disclosed is an electronic cassette provided with a cable which has a connector at an end thereof so as to be connected to an external device. Even in a case where the electronic cassette is inserted between a bed and a human body, the connector is designed to protrude from the human body, so that the electronic cassette during use on the bed can be easily connected to the external device (for example, refer to Japanese Patent Application Laid-Open (JP-A) No. 2004-173907) [0009] In addition, disclosed is an X-ray imaging apparatus in which a cassette inserting position is provided under a top board of a bed (for example, refer to Japanese Patent Application Laid-Open (JP-A) No. 2004-160263). [0010] However, in the electronic cassette disclosed in JP-A No. 2004-173907, since the electronic cassette is inserted between the bed and the to-be-tested person, the person may feel unpleasant. In addition, since the cable or the connector exists on the bed, there is a problem in that the cable or the connector may interfere with the loading of the to-be-test person on the bed or the handling of the electronic cassette by an operator. In addition, there is a problem in that the photographable portion may be limited depending on a length of the cable. [0011] In addition, in the X-ray imaging apparatus disclosed in JP-A No. 2004-160263, there is a problem in that the cassette inserting position is fixed and the photographable portion is limited. SUMMARY [0012] An object of the invention is to provide a radiographic imaging table in which a cable or a connector cannot interfere with imaging and an imaged portion is also not limited even in a case where charging or data-transmitting of a radiographic image detector in the imaging table is performed. [0013] In order to achieve the above object, a first aspect of present invention provides a radiographic imaging table including: [0014] a test object mounting plate capable of allowing radiation to penetrate therethrough, on which a test object is mounted; [0015] a detector mounting plate which is disposed under the test object mounting plate to movably mount a radiographic image detector which detects radiation penetrating the test object and the test object mounting plate, and which generates an image according to the detected radiation; and [0016] a connection device which is disposed on the detector mounting plate such that it is connectable to the radiographic image detector in order to perform at least one of charging the radiographic image detector mounted on the detector mounting plate or facilitating communication between the radiographic image detector and an external device. [0017] In this manner, the charging of the radiographic image detector and the communication between the radiographic image detector and the external device can be performed in the state that the radiographic image detector remains on the radiographic imaging table. Since the connection device needed for the charging and the communication is provided to the detector mounting plate, the cable or the connector does not protrude on the test object mounting plate or from the side surface of the radiographic imaging table, and the cable or the connector cannot interfere with the imaging. In addition, the radiographic image detector can move on the substantially entire surface of the detector mounting plate to the position of the test object on the test object mounting plate, and the imaged portion is not limited. Moreover, since there is no need for inserting the radiographic image detector between the test object mounting plate and the test object, there is no load to the test object. [0018] In addition, the radiographic imaging table according to the invention may be constructed to include a tray on which the radiographic image detector movably mounted on the detector mounting plate is mounted. [0019] In addition, a tray connection member for connecting the radiographic image detector with the connection device may be provided to the tray. Accordingly, the connection device can be connected to the radiographic image detector in the state that the radiographic image detector remains mounted on the tray. [0020] In addition, the tray may be movably provided in one of long-side and short-side directions of the detector mounting plate along a pair of second tracks which are movably provided along a pair of first tracks which are provided along the other of the long-side and short-side directions of the detector mounting plate, and the tracks may be constructed with rails or grooves. Accordingly, the movement of the radiographic image detector mounted on the tray can be more easily performed. [0021] In addition, the first and second tracks may be constructed with rails made of a conductive member, and the charging of the radiographic image detector or the communication between the radiographic image detector and an external device may be performed through the first and second tracks. Accordingly, the charging or communication of the radiographic image detector mounted on the tray can be performed without movement of the tray to the position of the connection device disposed in a predetermined position, so that convenience can be improved. [0022] In addition, a second aspect of the present invention provides a radiographic imaging table including: [0023] a test object mounting plate capable of allowing radiation to penetrate therethrough, on which a test object is mounted; [0024] a detector mounting plate which is disposed under the test object mounting plate to movably mount a radiographic image detector which detects radiation penetrating the test object and the test object mounting plate, and which generates an image according to the detected radiation; and [0025] a pair of first rails in one of a length or width direction of the detector mounting plate, a pair of second rails movably provided along the pair of first rails, and a tray provided so as to be capable of moving along the pair of second rails in the other of the length or width direction of the detector mounting plate, [0026] wherein the first and second rails comprise a conductive member, and [0027] charging of the radiographic image detector or communication between the radiographic image detector and an external device is performed through the first and second rails. [0028] In addition, a radiation absorbing member may be disposed on a surface of the tray. Accordingly, there is no need for providing a radiation absorbing member to the radiographic image detector. The radiographic image detector can thus be constructed with a light weight. [0029] In addition, a power supply unit may be disposed to an inner portion of the detector mounting plate or under the detector mounting plate to supply power, in a non-contact manner, to a power receiving member provided to the radiographic image detector through electromagnetic induction so as to receive a power for charging an embedded battery. Accordingly, at the time of charging, there is no need for connecting the electronic cassette to the connection device, so that convenience can be improved. [0030] In addition, a third aspect of the present invention provides a radiographic imaging table including: [0031] a test object mounting plate capable of allowing radiation to penetrate therethrough, on which a test object is mounted; [0032] a detector mounting plate which is disposed under the test object mounting plate to movably mount a radiographic image detector which detects radiation penetrating the test object and the test object mounting plate, and which generates an image according to the detected radiation; and [0033] a power supply unit which is disposed at an inner portion of the detector mounting plate or under the detector mounting plate, to supply power in a non-contact manner to a power receiving member provided to the radiographic image detector through electromagnetic induction so that the power receiving member receives a power for charging an internal battery. [0034] In addition, a radiation absorbing member may be disposed on a surface of the detector mounting plate. In a construction where the tray is not provided, by disposing the radiation absorbing member on a surface of the detector mounting plate, the radiographic image detector can be constructed with a light weight, similarly to the case where the radiation absorbing member is provided to the tray. [0035] As described above, according to the radiographic imaging table of the invention, even in a case where charging or data-transmitting of a radiographic image detector in the imaging table is performed, there is an advantage in that a cable or a connector cannot interfere with imaging and an imaged portion is also not limited. BRIEF DESCRIPTION OF THE DRAWINGS [0036] Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein: [0037] FIG. 1 is a schematic side view illustrating a radiographic imaging table according to a first exemplary embodiment; [0038] FIG. 2 is a schematic view illustrating a connector of the radiographic imaging table according to the first exemplary embodiment; [0039] FIG. 3A is a schematic perspective view illustrating a radiographic imaging table according to a second exemplary embodiment; [0040] FIG. 3B is a plan view illustrating a cassette mounting plate of the radiographic imaging table according to the second exemplary embodiment; [0041] FIG. 4 is a side view illustrating a tray of the radiographic imaging table according to the second exemplary embodiment; [0042] FIG. 5 is a schematic view illustrating a tray connection member of the radiographic imaging table according to the second exemplary embodiment; [0043] FIG. 6A is a plan view illustrating a cassette mounting plate of a radiographic imaging table according to a modified example of the second exemplary embodiment; [0044] FIG. 6B is a side view illustrating a tray of the radiographic imaging table according to the modified example of the second exemplary embodiment; [0045] FIG. 7A is a schematic side view illustrating a radiographic imaging table according to a third exemplary embodiment; [0046] FIG. 7B is a plan view illustrating a cassette mounting plate of the radiographic imaging table according to the third exemplary embodiment; and [0047] FIG. 8 is a side view illustrating a power transmitting coil of a radiographic imaging table according to a fourth exemplary embodiment; DETAILED DESCRIPTION [0048] Hereinafter, exemplary embodiments of the invention will be described in detail with reference to the accompanying drawings. [0049] As shown in FIG. 1 , in a radiographic imaging table 10 according to a first exemplary embodiment, at the time of radiographic imaging, a test object 19 is loaded on a top board 12 described later. When radiographic imaging is commanded, a radiation generating unit 18 which generates a radiation such as an X-ray emits the radiation with a radiation amount according to predetermined imaging conditions. The radiation emitted from the radiation generating unit 18 penetrates the test object 19 positioned at an imaging position. The radiation containing image information penetrates the top board 12 to be irradiated on a portable radiographic image detecting device (hereinafter, referred to as an “electronic cassette”) 20 mounted on a cassette mounting plate 14 described later. Accordingly, in the electronic cassette 20 , the radiographic image is detected. [0050] As the electronic cassette 20 , a direct-conversion electronic cassette in which the radiation is directly converted to charges by using a radiation-charge conversion material such as amorphous selenium and an indirect-conversion electronic cassette in which the radiation is indirectly converted to charges by performing a radiation-photon conversion by using a fluorescent material such as gadolinium oxysulfide (GOS) or cesium iodide (CsI) and performing a photon-charge conversion by using a photoelectric conversion device such as a photodiode may be used. [0051] The radiographic imaging table 10 includes the top board 12 capable of penetrating the radiation, on which the test object 19 is loaded, the cassette mounting plate 14 which is disposed under the top board 12 to mount the electronic cassette 20 thereon, and a connector 16 which is disposed on the cassette mounting plate 14 , so that connection for charging of the electronic cassette 20 and transmitting of data can be provided. The top board 12 and the cassette mounting plate 14 have substantially the same shape. The radiographic imaging table 10 has a two-layer structure in which the cassette mounting plate 14 serves as the bottom layer and the top board 12 as the top layer. [0052] The top board 12 is made of a material capable of penetrating a radiation and having a strength so that the test object 19 can be loaded. As the top board 12 , for example, an acryl board, a carbon board, wood, or a combination thereof can be used. [0053] In the cassette mounting plate 14 , substantially the entire surface thereof is used for a region on which the electronic cassette 20 can be mounted, and the electronic cassette 20 can be disposed at a position corresponding to the position of the test object 19 loaded on the top board 12 . In addition, a lead plate as a radiation absorbing member may be disposed on a surface of the cassette mounting plate 14 , so that a back scattered radiation in the electronic cassette 20 can be absorbed. In this manner, since the lead plate is disposed on the surface of the cassette mounting plate 14 , a lead plate provided to the electronic cassette 20 can be omitted. Therefore, the electronic cassette 20 can be constructed with a light weight. [0054] Preferably, a gap between the top board 12 and the cassette mounting plate 14 is as short as possible. As the gap between the top board 12 and the cassette mounting plate 14 is increased, the distance between the test object 19 and the electronic cassette 20 is also increased, and thus, magnification imaging may be unintentionally performed. In terms of the handling of the electronic cassette 20 , there is a need for providing a suitable empty gap. In case of outputting or displaying a captured image, image processing for obtaining an equally-magnified image by taking a reciprocal number of a magnification ratio corresponding to the gap between the top board 12 and the cassette mounting plate 14 may be performed. [0055] As shown in FIG. 2 , the connector 16 is disposed at a portion (for example, a corner) of the cassette mounting plate 14 . The connector 16 is connected through a cable to an AC power supply and an external device, that is, a console so as to be connected to a cassette connection member 22 provided to the electronic cassette 20 . Accordingly, the electronic cassette 20 can be connected to the AC power supply and the console. [0056] Next, operations of the radiographic imaging table 10 according to the first exemplary embodiment will be described. [0057] At the time of imaging, the test object 19 is loaded on the top board 12 . An operator mounts the electronic cassette 20 on the cassette mounting plate 14 . While checking the loaded position of the test object 19 on the top board 12 , the operator moves the electronic cassette 20 to a corresponding position on the cassette mounting plate 14 . Alternatively, before the test object 19 is loaded on the top board 12 , the electronic cassette 20 may be mounted on the cassette mounting plate 14 in advance. [0058] When the imaging is ended, the operator moves the electronic cassette 20 on the cassette mounting plate 14 to the position where the connector 16 is disposed, so that the cassette connection member 22 is connected to the connector 16 . Since the connector 16 is connected through a cable to the AC power supply, power is supplied from the AC power supply, so that the battery embedded in the electronic cassette 20 is charged with power as much as consumed power. In addition, since the connector 16 is connected through a cable to the console, in response to an operator's command of transmitting image data, the image data stored in a memory provided in the electronic cassette 20 is transmitted to the console. [0059] In addition, the console is connected to a radiology information system (RIS, not shown) which collectively manages radiographic image information or others handled in the department of radiology of a hospital. The RIS is connected to a hospital information system (HIS, not shown) which collectively manages medical information of a hospital. Therefore, in the console, since power that is to be consumed by the electronic cassette 20 in the next imaging can be requested, the charging with the power corresponding to the to-be-consumed power can be controlled. [0060] When the charging of the battery or the transmitting of data is ended, the cassette connection member 22 is disconnected from the connector 16 . The electronic cassette 20 remains mounted on the cassette mounting plate 14 for the next imaging. [0061] In the radiographic imaging table according to the first exemplary embodiment, since the connector for the charging or the transmitting of data is disposed to the cassette mounting plate disposed under the top board, the cable or the connector cannot interfere with the loading or unloading of the test object, that is, a patient or the operator's handling of the electronic cassette in comparison with a case where the cable or the connector is disposed on the top board or to a side portion of the bed. In addition, since the electronic cassette can be mounted on any position of the cassette mounting plate, the imaged portion is not limited and there is no pulling of the cable. In addition, since the inserting of the electronic cassette between the top board and the test object is unnecessary, the load to the test object can be lowered. [0062] Next, a radiographic imaging table according to a second exemplary embodiment will be described. The same elements as those of the radiographic imaging table 10 according to the first exemplary embodiment are denoted by the same reference numerals, and the description thereof is omitted. [0063] As shown in FIG. 3A , a radiographic imaging table 210 according to the second exemplary embodiment has the same construction as that of the radiographic imaging table 10 according to the first exemplary embodiment in that a top board 12 and a cassette mounting plate 214 constitute a two-layer structure. However, as shown in FIGS. 3A and 3B , there is a difference in that a tray 30 for mounting the electronic cassette 20 thereon is disposed on the cassette mounting plate 214 and long-side-direction and short-side-direction rails 32 and 34 for moving the tray 30 on the cassette mounting plate 214 are disposed. [0064] The long-side-direction rail 32 has a shape of a bar having a circular cross section and a length substantially the same as the long-side length of the cassette mounting plate 214 . The long-side-direction rail 32 is fixed to a long-side-direction end region of the cassette mounting plate 214 . The short-side-direction rail 34 is disposed through a first slider 36 (described later) on the long-side-direction rail 32 . [0065] The short-side-direction rail 34 has a shape of a bar having a circular cross section and a length substantially the same as the short-side length of the cassette mounting plate 214 . The short-side-direction rail 34 is constructed with a pair of short-side-direction rails that are disposed in parallel to the short-side direction of the cassette mounting plate 214 and separated from each other by a distance corresponding to a width of the tray 30 described later. [0066] As shown in FIG. 4 , the first sliders 36 are fixed to portions of the short-side-direction rails 34 , where the short-side-direction rails 34 and the long-side-direction rails 32 are in contact with each other. The first slider 36 has a semi-cylindrical shape, and an inner diameter portion thereof has a shape coincident with a circumferential surface of the long-side-direction rail 32 . The first slider 36 is superposed on the long-side-direction rail 32 , so that the short-side-direction rail 34 fixed to the first slider 36 can be slid along the long-side-direction rail 32 . In addition, stoppers (not shown) are provided to the ends of the long-side-direction rail 32 so as to limit the sliding of the short-side-direction rail 34 . [0067] The tray 30 on which the electronic cassette 20 can be mounted is disposed on the short-side-direction rails 34 through second sliders 38 . The second sliders 38 are fixed to portions of the lower surface of the tray 30 , where the short-side-direction rails 34 are in contact with the tray 30 . The second slider 38 has a semi-cylindrical shape, and an inner diameter portion thereof has a shape coincident with a circumferential surface of the short-side-direction rail 34 . The second slider 38 is superposed on the short-side-direction rail 34 , so that the tray 30 fixed to the second slider 38 can be slid along the short-side-direction rail 34 . In addition, stoppers (not shown) are provided to the ends of the short-side-direction rail 34 so as to limit the sliding of the tray 30 . [0068] In addition, as shown in FIG. 5 , a tray connection member 40 is provided to a portion (for example, a corner) of the tray 30 . The cassette connection member 22 is inserted into the tray connection member 40 . An inner side of the tray connection member 40 can be connected to the cassette connection member 22 of the electronic cassette 20 , and an outer side of the tray connection member 40 can be connected to a connector 216 provided to the cassette mounting plate 14 . In addition, the connector 216 is connected through a cable to the AC power supply and the console. Accordingly, in the state that the cassette connection member 22 is connected to the tray connection member 40 , the tray connection member 40 is connected to the connector 216 , so that the electronic cassette 20 can be connected to the AC power supply and the console. [0069] In addition, a lead plate as a radiation absorbing member is attached on an inner surface of the tray 30 on which the electronic cassette 20 is mounted, so that backward scattered radiation in the electronic cassette 20 can be absorbed. In this manner, since the lead plate is disposed on the inner surface of the tray 30 , a lead plate provided to the electronic cassette 20 can be omitted. Therefore, the electronic cassette 20 can be constructed with a light weight. In addition, similarly to the radiographic imaging table according to the first exemplary embodiment, it is possible to reduce production costs in comparison with a case where a lead plate is disposed on the entire surface of the cassette mounting plate. [0070] Next, operations of the radiographic imaging table 210 according to the second exemplary embodiment will be described. [0071] At the time of imaging, the test object 19 is loaded on the top board 12 . An operator mounts the electronic cassette 20 on the tray 30 . While checking the loaded position of the test object 19 on the top board 12 , the operator moves the tray 30 on which the electronic cassette 20 is mounted, to a corresponding position on the cassette mounting plate 214 . At this time, the movement on the cassette mounting plate 214 in the short-side direction is performed by sliding the tray 30 along the short-side-direction rails 34 . The movement on the cassette mounting plate 214 in the long-side direction is performed by sliding the short-side-direction rails 34 to which the tray 30 is fixed, along the long-side-direction rails 32 . [0072] Alternatively, before the test object 19 is loaded on the top board 12 , the electronic cassette 20 may be mounted on the tray 30 in advance. In addition, the electronic cassette 20 may be mounted on the tray 30 so that the cassette connection member 22 is connected to the tray connection member 40 . [0073] When the imaging is ended, the operator moves the tray 30 on which the electronic cassette 20 is mounted, to the position where the connector 216 is disposed. In this step, if the cassette connection member 22 and the tray connection member 40 are not in the connected state, the cassette connection member 22 is first connected to the tray connection member 40 , after which the tray connection member 40 is connected to the connector 216 . Since the connector 216 is connected through a cable to the AC power supply, power is supplied from the AC power supply, so that the battery embedded in the electronic cassette 20 is charged through the tray connection member 40 with power as much as consumed power. In addition, since the connector 216 is connected through a cable to the console, in response to an operator's command of transmitting image data, the image data stored in a memory provided in the electronic cassette 20 is transmitted through the tray connection member 40 to the console. [0074] When the charging of the battery or the transmitting of data is ended, the tray connection member 40 is disconnected from the connector 216 . The electronic cassette 20 remains mounted on the tray 30 for the next imaging. [0075] In addition, the console is connected to a radiology information system (RIS, not shown) which collectively manages radiographic image information or others handled in the department of radiology of a hospital. The RIS is connected to a hospital information system (HIS, not shown) which collectively manages medical information of a hospital. Therefore, in the console, since power that is to be consumed by the electronic cassette 20 in the next imaging can be requested, the charging with the power corresponding to the to-be-consumed power can be controlled. [0076] In the radiographic imaging table according to the second exemplary embodiment, since the tray is moved along the long-side-direction rails and the short-side-direction rails, the electronic cassette mounted on the tray can be moved. In addition, since the tray connection member for connecting the cassette connection member with the connector is provided to the tray, in the state that the electronic cassette is mounted on the tray, the electronic cassette can be connected to the connector. In addition, the electronic cassette can be easily handled. [0077] In addition, in the second exemplary embodiment, the long-side-direction rails and the short-side-direction rails are formed to have a shape of a bar having a circular cross-section, but the invention is not limited thereto. The rails may be formed to have a shape of a bar having a square or triangular cross-section. In this case, the first and second sliders are formed to have a shape coincident with the shape of the cross-section of the rail. [0078] In addition, in the second exemplary embodiment, the construction where the long-side-direction rails are fixed to the cassette mounting plate has been described. However, alternatively, the short-side-direction rails are fixed to the short-side end region of the cassette mounting plate, and the long-side-direction rails are disposed through the first sliders on the short-side-direction rails. In this case, the electronic cassette can be moved in the long-side direction by sliding the tray along the long-side-direction rails, and the electronic cassette can be moved in the short-side direction by moving the long-side-direction rails to which the tray is fixed, along the short-side-direction rails. [0079] In addition, an image processing circuit board having a correction processing function or an image processing function for the radiographic image of the test object 19 imaged with the electronic cassette 20 is provided to the tray 30 , so that there is no need for providing the functions to the inner portion of the electronic cassette. In this case, since only the function of capturing a radiographic image is provided to the electronic cassette 20 , a small-sized, light-weight electronic cassette can be implemented. [0080] Next, a modified example of the second exemplary embodiment will be described. [0081] As shown in FIG. 6 , in a radiographic imaging table 2210 according to the modified example of the second exemplary embodiment, instead of rails, grooves are formed as tracks for moving a tray 230 . [0082] Long-side-direction grooves 232 having a length substantially the same as the long-side length of a cassette mounting plate 2214 are formed in long-side-direction end regions of the cassette mounting plate 2214 . [0083] In addition, a short-side-direction plate 233 having a length substantially the same as the short-side length of the cassette mounting plate 2214 and a width capable of mounting the tray 30 is disposed on the cassette mounting plate 2214 . As shown in FIG. 6B , on a lower surface of the short-side-direction plate 233 , first sliders 236 are disposed at positions corresponding to the long-side-direction grooves 232 . Each of the first sliders 236 may be constructed with a cylindrical skid (roller). By sliding the skids in the long-side-direction grooves 232 , the short-side-direction plate 233 can be slid along the long-side-direction grooves 232 . [0084] In addition, short-side-direction grooves 234 having a length substantially the same as the short-side length of the cassette mounting plate 2214 (that is, a length substantially the same as the long-side length of the short-side-direction plate 233 ) are formed in end regions of the short-side-direction plate 232 corresponding to the short-side direction of the cassette mounting plate 2214 . In the tray 30 , second sliders 238 are disposed at positions corresponding to the short-side-direction grooves 234 . Each of the second sliders 238 may be constructed with a cylindrical skid. By sliding the skids in the short-side-direction grooves 234 , the tray 230 can be slid along the short-side-direction grooves 234 . [0085] Accordingly, in the modified example, the electronic cassette can also be easily handled. [0086] Next, a radiographic imaging table according to a third exemplary embodiment will be described. The same elements as those of the radiographic imaging table according to the second exemplary embodiment are denoted by the same reference numerals, and the description thereof is omitted. [0087] As shown in FIG. 7 , a radiographic imaging table 310 according to the third exemplary embodiment has the same construction as that of the radiographic imaging table 210 according to the second exemplary embodiment in that the top board 12 and the cassette mounting plate 214 constitute a two-layer structure and a tray 330 , long-side-direction rails 332 and short-side-direction rails 334 are disposed on the cassette mounting plate 214 . However, there is a difference in that the long-side-direction rails 332 and the short-side-direction rails 334 are also used as a power supply line and a data line. [0088] First sliders (not shown) and second sliders (not shown) corresponding to the long-side-direction rails 332 and short-side-direction rails 334 a and 334 b and a tray connection member 340 are constructed with a conductive material. The second slider is fixed to a position which is in contact with the tray connection member 340 of the tray 330 . In addition, on a lower surface of the cassette mounting plate 214 , a power supply unit 50 connected to the AC power supply is disposed. The power supply unit 50 and the long-side-direction rails are connected to each other through wire lines. [0089] When the tray connection member 340 and the cassette connection member 22 are connected to each other, power from the power supply unit 50 is supplied to the electronic cassette 20 through the long-side-direction rails 332 , the first slider, the short-side-direction rail 334 b, the second slider, and the tray connection member 340 . [0090] Next, operations of the radiographic imaging table 310 according to the third exemplary embodiment will be described. [0091] At the time of imaging, the test object 19 is loaded on the top board 12 . An operator mounts the electronic cassette 20 on the tray 330 . At this time, the cassette connection member 22 and the tray connection member 340 are not connected to each other. While checking the loaded position of the test object 19 on the top board 12 , the operator moves the tray 330 on which the electronic cassette 20 is mounted, to a corresponding position on the cassette mounting plate 214 . At this time, the movement on the cassette mounting plate 214 in the short-side direction is performed by sliding the tray 330 along the shot-side-direction rails 334 . The movement on the cassette mounting plate 214 in the long-side direction is performed by sliding the short-side-direction rails 334 to which the tray 330 is fixed, along the long-side-direction rails 332 . [0092] When the imaging is ended, the tray 330 remains in the position, or the tray 330 is moved to a position where the operator can easily handle it. In this state, the cassette connection member 22 is connected to the tray connection member 340 . As a result, power corresponding to the consumed power is supplied from the power supply unit 50 through the long-side-direction rail 332 , the first slider, the short-side-direction rail 334 b , the second slider, and the tray connection member 340 . [0093] In addition, when the long-side-direction rail 332 is connected not to the power supply unit 50 but to the console, the cassette connection member 22 is connected to the tray connection member 340 , so that the image data stored in the memory included in the electronic cassette 20 can be transmitted through the tray connection member 40 to the console. [0094] When the charging of the battery or the transmitting of data is ended, the cassette connection member 22 is disconnected from the tray connection member 40 . The electronic cassette 20 remains mounted on the tray 330 for the next imaging. [0095] In addition, the console is connected to a radiology information system (RIS, not shown) which collectively manages radiographic image information or others handled in the department of radiology of a hospital. The RIS is connected to a hospital information system (HIS, not shown) which collectively manages medical information of a hospital. Therefore, in the console, since power that is to be consumed by the electronic cassette 20 in the next imaging can be requested, the charging with the power corresponding to the to-be-consumed power can be controlled. [0096] In the radiographic imaging table according to the third exemplary embodiment, the charging of the electronic cassette and the transmitting of data can be performed without movement of the tray to the position of the connector disposed to a predetermined position, so that convenience can be improved. [0097] In addition, in the third exemplary embodiment, the short-side-direction rail 334 b is constructed with a conductive material. This construction is provided in order to simplify a connection mechanism between the tray connection member 340 , the second slider, and the short-side-direction rails, by taking into consideration the construction where the tray connection member 340 is provided to the short-side-direction rail 334 b . Alternatively, the short-side-direction rail 334 a may be constructed with a conductive material, and a wire line between the tray connection member 340 and the second slider may be disposed on a rear surface of the tray 330 . [0098] In addition, since the charging of the electronic cassette and the communication with an external device can be performed through the rails, there is no need for providing the connector that is provided in the first and second exemplary embodiments. However, the connector may also be provided so that the charging and communication through the rails as well as the charging and communication through connection of the tray to the connector can be performed. Due to the construction, various types of electronic cassettes can be adaptively implemented. [0099] Next, a radiographic imaging table according to a fourth exemplary embodiment will be described. The same elements as those of the radiographic imaging table according to the first to third exemplary embodiments are denoted by the same reference numerals, and the description thereof is omitted. [0100] As shown in FIG. 8 , in a radiographic imaging table 410 according to the fourth exemplary embodiment, a power transmitting coil 60 functioning as a primary coil for charging a battery of an electronic cassette in a non-contact manner is disposed in an inner portion of a cassette mounting plate 414 . The power transmitting coil 60 is connected to an AC power supply. In addition, the power transmitting coil 60 may be disposed on a lower surface of the cassette mounting plate 414 instead of an inner portion of the cassette mounting plate 414 . [0101] An electronic cassette 420 is provided with a power receiving coil 24 functioning as a secondary coil, a charging circuit 26 for rectifying an electromotive force generated in the power receiving coil 24 , and a battery 28 . [0102] Next, operations of the radiographic imaging table 410 according to the fourth exemplary embodiment will be described. [0103] At the time of imaging, the test object 19 is loaded on the top board 12 . An operator mounts the electronic cassette 420 on a tray 430 . While checking the loaded position of the test object 19 on the top board 12 , the operator moves the tray 430 on which the electronic cassette 420 is mounted, to a corresponding position on the cassette mounting plate 414 . At this time, the movement on the cassette mounting plate 414 in the short-side direction is performed by sliding the tray 430 along the short-side-direction rails 34 . The movement on the cassette mounting plate 414 in the long-side direction is performed by sliding the short-side-direction rails 34 to which the tray 430 is fixed, along the long-side-direction rails 32 . [0104] When the imaging is ended, the tray 430 is moved to a charging position where the power transmitting coil 60 is disposed. Magnetic field is generated from the power transmitting coil 60 applied with the AC power due to electromagnetic induction. The electromotive force induced to the power receiving coil 24 by the magnetic field is rectified by the charging circuit 26 , and the battery 28 is charged. When the charging of the battery 28 is ended, the tray 430 is moved from the charging position. [0105] In this manner, in the radiographic imaging table according to the fourth exemplary embodiment, since the battery of the electronic cassette can be charged in a non-contact manner, there is no need for connecting the battery to the connector at the time of charging. Accordingly, convenience can be improved. [0106] In addition, in the fourth exemplary embodiment, since the charging of the electronic cassette can be performed in a non-contact manner, there is no need for connection to the connector according to the first and second exemplary embodiments. However, a connector may be provided so as to perform communication with an external device or to perform the non-contact charging as well as the charging using a wire line connected to the connector. Due to the connector, various types of electronic cassettes can be adaptively implemented.
There is provided a radiographic imaging table including: a test object mounting plate capable of allowing radiation to penetrate therethrough, on which a test object is mounted; a detector mounting plate which is disposed under the test object mounting plate to movably mount a radiographic image detector which detects radiation penetrating the test object and the test object mounting plate, and which generates an image according to the detected radiation; and a connection device which is disposed on the detector mounting plate such that it is connectable to the radiographic image detector in order to perform at least one of charging the radiographic image detector mounted on the detector mounting plate or facilitating communication between the radiographic image detector and an external device.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2008-247315 filed on Sep. 26, 2008, the disclosure of which is incorporated by reference herein.", "BACKGROUND [0002] 1.", "Field of the Invention [0003] The invention relates to a radiographic imaging table and, more particularly, to a radiographic imaging table used for imaging using a portable radiographic image detector.", "[0004] 2.", "Description of the Related Art [0005] Recently, a flat panel detector (FPD) that is constructed by disposing a radiation sensitive layer on a thin film transistor (TFT) active matrix substrate has been put to practical applications.", "The FPD can directly convert an X-ray into digital data.", "A portable radiographic image detecting device (hereinafter, referred to as an “ electronic cassette”) for generating image data indicating a radiographic image represented by a radiation penetrating a test object and being irradiated by using the FPD and storing the generated image data has been put to practical applications.", "[0006] Since the electronic cassette has good portability, a test object loaded on a stretcher or a bed can be imaged.", "In addition, since an imaged portion can be adjusted by changing a position of the electronic cassette, even an immobile patient as an example of the test object can be adaptively imaged.", "[0007] Such a portable electronic cassette is embedded with a memory for storing the image data of the captured images and a battery.", "The electronic cassette is inserted into a dedicated cassette stand so as to transmit the image data to an external device, that is, a console or to charge the embedded battery (for example, refer to Japanese Patent Application Laid-Open (JP-A) No. 2000-206636).", "However, every time the electronic cassette used with a bed is to be charged or the image data is to be transmitted, the electronic cassette needs to be moved to the cassette stand.", "Particularly, there is great inconvenience in a case where the bed and the cassette stand are separated from each other over a long distance.", "[0008] Therefore, disclosed is an electronic cassette provided with a cable which has a connector at an end thereof so as to be connected to an external device.", "Even in a case where the electronic cassette is inserted between a bed and a human body, the connector is designed to protrude from the human body, so that the electronic cassette during use on the bed can be easily connected to the external device (for example, refer to Japanese Patent Application Laid-Open (JP-A) No. 2004-173907) [0009] In addition, disclosed is an X-ray imaging apparatus in which a cassette inserting position is provided under a top board of a bed (for example, refer to Japanese Patent Application Laid-Open (JP-A) No. 2004-160263).", "[0010] However, in the electronic cassette disclosed in JP-A No. 2004-173907, since the electronic cassette is inserted between the bed and the to-be-tested person, the person may feel unpleasant.", "In addition, since the cable or the connector exists on the bed, there is a problem in that the cable or the connector may interfere with the loading of the to-be-test person on the bed or the handling of the electronic cassette by an operator.", "In addition, there is a problem in that the photographable portion may be limited depending on a length of the cable.", "[0011] In addition, in the X-ray imaging apparatus disclosed in JP-A No. 2004-160263, there is a problem in that the cassette inserting position is fixed and the photographable portion is limited.", "SUMMARY [0012] An object of the invention is to provide a radiographic imaging table in which a cable or a connector cannot interfere with imaging and an imaged portion is also not limited even in a case where charging or data-transmitting of a radiographic image detector in the imaging table is performed.", "[0013] In order to achieve the above object, a first aspect of present invention provides a radiographic imaging table including: [0014] a test object mounting plate capable of allowing radiation to penetrate therethrough, on which a test object is mounted;", "[0015] a detector mounting plate which is disposed under the test object mounting plate to movably mount a radiographic image detector which detects radiation penetrating the test object and the test object mounting plate, and which generates an image according to the detected radiation;", "and [0016] a connection device which is disposed on the detector mounting plate such that it is connectable to the radiographic image detector in order to perform at least one of charging the radiographic image detector mounted on the detector mounting plate or facilitating communication between the radiographic image detector and an external device.", "[0017] In this manner, the charging of the radiographic image detector and the communication between the radiographic image detector and the external device can be performed in the state that the radiographic image detector remains on the radiographic imaging table.", "Since the connection device needed for the charging and the communication is provided to the detector mounting plate, the cable or the connector does not protrude on the test object mounting plate or from the side surface of the radiographic imaging table, and the cable or the connector cannot interfere with the imaging.", "In addition, the radiographic image detector can move on the substantially entire surface of the detector mounting plate to the position of the test object on the test object mounting plate, and the imaged portion is not limited.", "Moreover, since there is no need for inserting the radiographic image detector between the test object mounting plate and the test object, there is no load to the test object.", "[0018] In addition, the radiographic imaging table according to the invention may be constructed to include a tray on which the radiographic image detector movably mounted on the detector mounting plate is mounted.", "[0019] In addition, a tray connection member for connecting the radiographic image detector with the connection device may be provided to the tray.", "Accordingly, the connection device can be connected to the radiographic image detector in the state that the radiographic image detector remains mounted on the tray.", "[0020] In addition, the tray may be movably provided in one of long-side and short-side directions of the detector mounting plate along a pair of second tracks which are movably provided along a pair of first tracks which are provided along the other of the long-side and short-side directions of the detector mounting plate, and the tracks may be constructed with rails or grooves.", "Accordingly, the movement of the radiographic image detector mounted on the tray can be more easily performed.", "[0021] In addition, the first and second tracks may be constructed with rails made of a conductive member, and the charging of the radiographic image detector or the communication between the radiographic image detector and an external device may be performed through the first and second tracks.", "Accordingly, the charging or communication of the radiographic image detector mounted on the tray can be performed without movement of the tray to the position of the connection device disposed in a predetermined position, so that convenience can be improved.", "[0022] In addition, a second aspect of the present invention provides a radiographic imaging table including: [0023] a test object mounting plate capable of allowing radiation to penetrate therethrough, on which a test object is mounted;", "[0024] a detector mounting plate which is disposed under the test object mounting plate to movably mount a radiographic image detector which detects radiation penetrating the test object and the test object mounting plate, and which generates an image according to the detected radiation;", "and [0025] a pair of first rails in one of a length or width direction of the detector mounting plate, a pair of second rails movably provided along the pair of first rails, and a tray provided so as to be capable of moving along the pair of second rails in the other of the length or width direction of the detector mounting plate, [0026] wherein the first and second rails comprise a conductive member, and [0027] charging of the radiographic image detector or communication between the radiographic image detector and an external device is performed through the first and second rails.", "[0028] In addition, a radiation absorbing member may be disposed on a surface of the tray.", "Accordingly, there is no need for providing a radiation absorbing member to the radiographic image detector.", "The radiographic image detector can thus be constructed with a light weight.", "[0029] In addition, a power supply unit may be disposed to an inner portion of the detector mounting plate or under the detector mounting plate to supply power, in a non-contact manner, to a power receiving member provided to the radiographic image detector through electromagnetic induction so as to receive a power for charging an embedded battery.", "Accordingly, at the time of charging, there is no need for connecting the electronic cassette to the connection device, so that convenience can be improved.", "[0030] In addition, a third aspect of the present invention provides a radiographic imaging table including: [0031] a test object mounting plate capable of allowing radiation to penetrate therethrough, on which a test object is mounted;", "[0032] a detector mounting plate which is disposed under the test object mounting plate to movably mount a radiographic image detector which detects radiation penetrating the test object and the test object mounting plate, and which generates an image according to the detected radiation;", "and [0033] a power supply unit which is disposed at an inner portion of the detector mounting plate or under the detector mounting plate, to supply power in a non-contact manner to a power receiving member provided to the radiographic image detector through electromagnetic induction so that the power receiving member receives a power for charging an internal battery.", "[0034] In addition, a radiation absorbing member may be disposed on a surface of the detector mounting plate.", "In a construction where the tray is not provided, by disposing the radiation absorbing member on a surface of the detector mounting plate, the radiographic image detector can be constructed with a light weight, similarly to the case where the radiation absorbing member is provided to the tray.", "[0035] As described above, according to the radiographic imaging table of the invention, even in a case where charging or data-transmitting of a radiographic image detector in the imaging table is performed, there is an advantage in that a cable or a connector cannot interfere with imaging and an imaged portion is also not limited.", "BRIEF DESCRIPTION OF THE DRAWINGS [0036] Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein: [0037] FIG. 1 is a schematic side view illustrating a radiographic imaging table according to a first exemplary embodiment;", "[0038] FIG. 2 is a schematic view illustrating a connector of the radiographic imaging table according to the first exemplary embodiment;", "[0039] FIG. 3A is a schematic perspective view illustrating a radiographic imaging table according to a second exemplary embodiment;", "[0040] FIG. 3B is a plan view illustrating a cassette mounting plate of the radiographic imaging table according to the second exemplary embodiment;", "[0041] FIG. 4 is a side view illustrating a tray of the radiographic imaging table according to the second exemplary embodiment;", "[0042] FIG. 5 is a schematic view illustrating a tray connection member of the radiographic imaging table according to the second exemplary embodiment;", "[0043] FIG. 6A is a plan view illustrating a cassette mounting plate of a radiographic imaging table according to a modified example of the second exemplary embodiment;", "[0044] FIG. 6B is a side view illustrating a tray of the radiographic imaging table according to the modified example of the second exemplary embodiment;", "[0045] FIG. 7A is a schematic side view illustrating a radiographic imaging table according to a third exemplary embodiment;", "[0046] FIG. 7B is a plan view illustrating a cassette mounting plate of the radiographic imaging table according to the third exemplary embodiment;", "and [0047] FIG. 8 is a side view illustrating a power transmitting coil of a radiographic imaging table according to a fourth exemplary embodiment;", "DETAILED DESCRIPTION [0048] Hereinafter, exemplary embodiments of the invention will be described in detail with reference to the accompanying drawings.", "[0049] As shown in FIG. 1 , in a radiographic imaging table 10 according to a first exemplary embodiment, at the time of radiographic imaging, a test object 19 is loaded on a top board 12 described later.", "When radiographic imaging is commanded, a radiation generating unit 18 which generates a radiation such as an X-ray emits the radiation with a radiation amount according to predetermined imaging conditions.", "The radiation emitted from the radiation generating unit 18 penetrates the test object 19 positioned at an imaging position.", "The radiation containing image information penetrates the top board 12 to be irradiated on a portable radiographic image detecting device (hereinafter, referred to as an “electronic cassette”) 20 mounted on a cassette mounting plate 14 described later.", "Accordingly, in the electronic cassette 20 , the radiographic image is detected.", "[0050] As the electronic cassette 20 , a direct-conversion electronic cassette in which the radiation is directly converted to charges by using a radiation-charge conversion material such as amorphous selenium and an indirect-conversion electronic cassette in which the radiation is indirectly converted to charges by performing a radiation-photon conversion by using a fluorescent material such as gadolinium oxysulfide (GOS) or cesium iodide (CsI) and performing a photon-charge conversion by using a photoelectric conversion device such as a photodiode may be used.", "[0051] The radiographic imaging table 10 includes the top board 12 capable of penetrating the radiation, on which the test object 19 is loaded, the cassette mounting plate 14 which is disposed under the top board 12 to mount the electronic cassette 20 thereon, and a connector 16 which is disposed on the cassette mounting plate 14 , so that connection for charging of the electronic cassette 20 and transmitting of data can be provided.", "The top board 12 and the cassette mounting plate 14 have substantially the same shape.", "The radiographic imaging table 10 has a two-layer structure in which the cassette mounting plate 14 serves as the bottom layer and the top board 12 as the top layer.", "[0052] The top board 12 is made of a material capable of penetrating a radiation and having a strength so that the test object 19 can be loaded.", "As the top board 12 , for example, an acryl board, a carbon board, wood, or a combination thereof can be used.", "[0053] In the cassette mounting plate 14 , substantially the entire surface thereof is used for a region on which the electronic cassette 20 can be mounted, and the electronic cassette 20 can be disposed at a position corresponding to the position of the test object 19 loaded on the top board 12 .", "In addition, a lead plate as a radiation absorbing member may be disposed on a surface of the cassette mounting plate 14 , so that a back scattered radiation in the electronic cassette 20 can be absorbed.", "In this manner, since the lead plate is disposed on the surface of the cassette mounting plate 14 , a lead plate provided to the electronic cassette 20 can be omitted.", "Therefore, the electronic cassette 20 can be constructed with a light weight.", "[0054] Preferably, a gap between the top board 12 and the cassette mounting plate 14 is as short as possible.", "As the gap between the top board 12 and the cassette mounting plate 14 is increased, the distance between the test object 19 and the electronic cassette 20 is also increased, and thus, magnification imaging may be unintentionally performed.", "In terms of the handling of the electronic cassette 20 , there is a need for providing a suitable empty gap.", "In case of outputting or displaying a captured image, image processing for obtaining an equally-magnified image by taking a reciprocal number of a magnification ratio corresponding to the gap between the top board 12 and the cassette mounting plate 14 may be performed.", "[0055] As shown in FIG. 2 , the connector 16 is disposed at a portion (for example, a corner) of the cassette mounting plate 14 .", "The connector 16 is connected through a cable to an AC power supply and an external device, that is, a console so as to be connected to a cassette connection member 22 provided to the electronic cassette 20 .", "Accordingly, the electronic cassette 20 can be connected to the AC power supply and the console.", "[0056] Next, operations of the radiographic imaging table 10 according to the first exemplary embodiment will be described.", "[0057] At the time of imaging, the test object 19 is loaded on the top board 12 .", "An operator mounts the electronic cassette 20 on the cassette mounting plate 14 .", "While checking the loaded position of the test object 19 on the top board 12 , the operator moves the electronic cassette 20 to a corresponding position on the cassette mounting plate 14 .", "Alternatively, before the test object 19 is loaded on the top board 12 , the electronic cassette 20 may be mounted on the cassette mounting plate 14 in advance.", "[0058] When the imaging is ended, the operator moves the electronic cassette 20 on the cassette mounting plate 14 to the position where the connector 16 is disposed, so that the cassette connection member 22 is connected to the connector 16 .", "Since the connector 16 is connected through a cable to the AC power supply, power is supplied from the AC power supply, so that the battery embedded in the electronic cassette 20 is charged with power as much as consumed power.", "In addition, since the connector 16 is connected through a cable to the console, in response to an operator's command of transmitting image data, the image data stored in a memory provided in the electronic cassette 20 is transmitted to the console.", "[0059] In addition, the console is connected to a radiology information system (RIS, not shown) which collectively manages radiographic image information or others handled in the department of radiology of a hospital.", "The RIS is connected to a hospital information system (HIS, not shown) which collectively manages medical information of a hospital.", "Therefore, in the console, since power that is to be consumed by the electronic cassette 20 in the next imaging can be requested, the charging with the power corresponding to the to-be-consumed power can be controlled.", "[0060] When the charging of the battery or the transmitting of data is ended, the cassette connection member 22 is disconnected from the connector 16 .", "The electronic cassette 20 remains mounted on the cassette mounting plate 14 for the next imaging.", "[0061] In the radiographic imaging table according to the first exemplary embodiment, since the connector for the charging or the transmitting of data is disposed to the cassette mounting plate disposed under the top board, the cable or the connector cannot interfere with the loading or unloading of the test object, that is, a patient or the operator's handling of the electronic cassette in comparison with a case where the cable or the connector is disposed on the top board or to a side portion of the bed.", "In addition, since the electronic cassette can be mounted on any position of the cassette mounting plate, the imaged portion is not limited and there is no pulling of the cable.", "In addition, since the inserting of the electronic cassette between the top board and the test object is unnecessary, the load to the test object can be lowered.", "[0062] Next, a radiographic imaging table according to a second exemplary embodiment will be described.", "The same elements as those of the radiographic imaging table 10 according to the first exemplary embodiment are denoted by the same reference numerals, and the description thereof is omitted.", "[0063] As shown in FIG. 3A , a radiographic imaging table 210 according to the second exemplary embodiment has the same construction as that of the radiographic imaging table 10 according to the first exemplary embodiment in that a top board 12 and a cassette mounting plate 214 constitute a two-layer structure.", "However, as shown in FIGS. 3A and 3B , there is a difference in that a tray 30 for mounting the electronic cassette 20 thereon is disposed on the cassette mounting plate 214 and long-side-direction and short-side-direction rails 32 and 34 for moving the tray 30 on the cassette mounting plate 214 are disposed.", "[0064] The long-side-direction rail 32 has a shape of a bar having a circular cross section and a length substantially the same as the long-side length of the cassette mounting plate 214 .", "The long-side-direction rail 32 is fixed to a long-side-direction end region of the cassette mounting plate 214 .", "The short-side-direction rail 34 is disposed through a first slider 36 (described later) on the long-side-direction rail 32 .", "[0065] The short-side-direction rail 34 has a shape of a bar having a circular cross section and a length substantially the same as the short-side length of the cassette mounting plate 214 .", "The short-side-direction rail 34 is constructed with a pair of short-side-direction rails that are disposed in parallel to the short-side direction of the cassette mounting plate 214 and separated from each other by a distance corresponding to a width of the tray 30 described later.", "[0066] As shown in FIG. 4 , the first sliders 36 are fixed to portions of the short-side-direction rails 34 , where the short-side-direction rails 34 and the long-side-direction rails 32 are in contact with each other.", "The first slider 36 has a semi-cylindrical shape, and an inner diameter portion thereof has a shape coincident with a circumferential surface of the long-side-direction rail 32 .", "The first slider 36 is superposed on the long-side-direction rail 32 , so that the short-side-direction rail 34 fixed to the first slider 36 can be slid along the long-side-direction rail 32 .", "In addition, stoppers (not shown) are provided to the ends of the long-side-direction rail 32 so as to limit the sliding of the short-side-direction rail 34 .", "[0067] The tray 30 on which the electronic cassette 20 can be mounted is disposed on the short-side-direction rails 34 through second sliders 38 .", "The second sliders 38 are fixed to portions of the lower surface of the tray 30 , where the short-side-direction rails 34 are in contact with the tray 30 .", "The second slider 38 has a semi-cylindrical shape, and an inner diameter portion thereof has a shape coincident with a circumferential surface of the short-side-direction rail 34 .", "The second slider 38 is superposed on the short-side-direction rail 34 , so that the tray 30 fixed to the second slider 38 can be slid along the short-side-direction rail 34 .", "In addition, stoppers (not shown) are provided to the ends of the short-side-direction rail 34 so as to limit the sliding of the tray 30 .", "[0068] In addition, as shown in FIG. 5 , a tray connection member 40 is provided to a portion (for example, a corner) of the tray 30 .", "The cassette connection member 22 is inserted into the tray connection member 40 .", "An inner side of the tray connection member 40 can be connected to the cassette connection member 22 of the electronic cassette 20 , and an outer side of the tray connection member 40 can be connected to a connector 216 provided to the cassette mounting plate 14 .", "In addition, the connector 216 is connected through a cable to the AC power supply and the console.", "Accordingly, in the state that the cassette connection member 22 is connected to the tray connection member 40 , the tray connection member 40 is connected to the connector 216 , so that the electronic cassette 20 can be connected to the AC power supply and the console.", "[0069] In addition, a lead plate as a radiation absorbing member is attached on an inner surface of the tray 30 on which the electronic cassette 20 is mounted, so that backward scattered radiation in the electronic cassette 20 can be absorbed.", "In this manner, since the lead plate is disposed on the inner surface of the tray 30 , a lead plate provided to the electronic cassette 20 can be omitted.", "Therefore, the electronic cassette 20 can be constructed with a light weight.", "In addition, similarly to the radiographic imaging table according to the first exemplary embodiment, it is possible to reduce production costs in comparison with a case where a lead plate is disposed on the entire surface of the cassette mounting plate.", "[0070] Next, operations of the radiographic imaging table 210 according to the second exemplary embodiment will be described.", "[0071] At the time of imaging, the test object 19 is loaded on the top board 12 .", "An operator mounts the electronic cassette 20 on the tray 30 .", "While checking the loaded position of the test object 19 on the top board 12 , the operator moves the tray 30 on which the electronic cassette 20 is mounted, to a corresponding position on the cassette mounting plate 214 .", "At this time, the movement on the cassette mounting plate 214 in the short-side direction is performed by sliding the tray 30 along the short-side-direction rails 34 .", "The movement on the cassette mounting plate 214 in the long-side direction is performed by sliding the short-side-direction rails 34 to which the tray 30 is fixed, along the long-side-direction rails 32 .", "[0072] Alternatively, before the test object 19 is loaded on the top board 12 , the electronic cassette 20 may be mounted on the tray 30 in advance.", "In addition, the electronic cassette 20 may be mounted on the tray 30 so that the cassette connection member 22 is connected to the tray connection member 40 .", "[0073] When the imaging is ended, the operator moves the tray 30 on which the electronic cassette 20 is mounted, to the position where the connector 216 is disposed.", "In this step, if the cassette connection member 22 and the tray connection member 40 are not in the connected state, the cassette connection member 22 is first connected to the tray connection member 40 , after which the tray connection member 40 is connected to the connector 216 .", "Since the connector 216 is connected through a cable to the AC power supply, power is supplied from the AC power supply, so that the battery embedded in the electronic cassette 20 is charged through the tray connection member 40 with power as much as consumed power.", "In addition, since the connector 216 is connected through a cable to the console, in response to an operator's command of transmitting image data, the image data stored in a memory provided in the electronic cassette 20 is transmitted through the tray connection member 40 to the console.", "[0074] When the charging of the battery or the transmitting of data is ended, the tray connection member 40 is disconnected from the connector 216 .", "The electronic cassette 20 remains mounted on the tray 30 for the next imaging.", "[0075] In addition, the console is connected to a radiology information system (RIS, not shown) which collectively manages radiographic image information or others handled in the department of radiology of a hospital.", "The RIS is connected to a hospital information system (HIS, not shown) which collectively manages medical information of a hospital.", "Therefore, in the console, since power that is to be consumed by the electronic cassette 20 in the next imaging can be requested, the charging with the power corresponding to the to-be-consumed power can be controlled.", "[0076] In the radiographic imaging table according to the second exemplary embodiment, since the tray is moved along the long-side-direction rails and the short-side-direction rails, the electronic cassette mounted on the tray can be moved.", "In addition, since the tray connection member for connecting the cassette connection member with the connector is provided to the tray, in the state that the electronic cassette is mounted on the tray, the electronic cassette can be connected to the connector.", "In addition, the electronic cassette can be easily handled.", "[0077] In addition, in the second exemplary embodiment, the long-side-direction rails and the short-side-direction rails are formed to have a shape of a bar having a circular cross-section, but the invention is not limited thereto.", "The rails may be formed to have a shape of a bar having a square or triangular cross-section.", "In this case, the first and second sliders are formed to have a shape coincident with the shape of the cross-section of the rail.", "[0078] In addition, in the second exemplary embodiment, the construction where the long-side-direction rails are fixed to the cassette mounting plate has been described.", "However, alternatively, the short-side-direction rails are fixed to the short-side end region of the cassette mounting plate, and the long-side-direction rails are disposed through the first sliders on the short-side-direction rails.", "In this case, the electronic cassette can be moved in the long-side direction by sliding the tray along the long-side-direction rails, and the electronic cassette can be moved in the short-side direction by moving the long-side-direction rails to which the tray is fixed, along the short-side-direction rails.", "[0079] In addition, an image processing circuit board having a correction processing function or an image processing function for the radiographic image of the test object 19 imaged with the electronic cassette 20 is provided to the tray 30 , so that there is no need for providing the functions to the inner portion of the electronic cassette.", "In this case, since only the function of capturing a radiographic image is provided to the electronic cassette 20 , a small-sized, light-weight electronic cassette can be implemented.", "[0080] Next, a modified example of the second exemplary embodiment will be described.", "[0081] As shown in FIG. 6 , in a radiographic imaging table 2210 according to the modified example of the second exemplary embodiment, instead of rails, grooves are formed as tracks for moving a tray 230 .", "[0082] Long-side-direction grooves 232 having a length substantially the same as the long-side length of a cassette mounting plate 2214 are formed in long-side-direction end regions of the cassette mounting plate 2214 .", "[0083] In addition, a short-side-direction plate 233 having a length substantially the same as the short-side length of the cassette mounting plate 2214 and a width capable of mounting the tray 30 is disposed on the cassette mounting plate 2214 .", "As shown in FIG. 6B , on a lower surface of the short-side-direction plate 233 , first sliders 236 are disposed at positions corresponding to the long-side-direction grooves 232 .", "Each of the first sliders 236 may be constructed with a cylindrical skid (roller).", "By sliding the skids in the long-side-direction grooves 232 , the short-side-direction plate 233 can be slid along the long-side-direction grooves 232 .", "[0084] In addition, short-side-direction grooves 234 having a length substantially the same as the short-side length of the cassette mounting plate 2214 (that is, a length substantially the same as the long-side length of the short-side-direction plate 233 ) are formed in end regions of the short-side-direction plate 232 corresponding to the short-side direction of the cassette mounting plate 2214 .", "In the tray 30 , second sliders 238 are disposed at positions corresponding to the short-side-direction grooves 234 .", "Each of the second sliders 238 may be constructed with a cylindrical skid.", "By sliding the skids in the short-side-direction grooves 234 , the tray 230 can be slid along the short-side-direction grooves 234 .", "[0085] Accordingly, in the modified example, the electronic cassette can also be easily handled.", "[0086] Next, a radiographic imaging table according to a third exemplary embodiment will be described.", "The same elements as those of the radiographic imaging table according to the second exemplary embodiment are denoted by the same reference numerals, and the description thereof is omitted.", "[0087] As shown in FIG. 7 , a radiographic imaging table 310 according to the third exemplary embodiment has the same construction as that of the radiographic imaging table 210 according to the second exemplary embodiment in that the top board 12 and the cassette mounting plate 214 constitute a two-layer structure and a tray 330 , long-side-direction rails 332 and short-side-direction rails 334 are disposed on the cassette mounting plate 214 .", "However, there is a difference in that the long-side-direction rails 332 and the short-side-direction rails 334 are also used as a power supply line and a data line.", "[0088] First sliders (not shown) and second sliders (not shown) corresponding to the long-side-direction rails 332 and short-side-direction rails 334 a and 334 b and a tray connection member 340 are constructed with a conductive material.", "The second slider is fixed to a position which is in contact with the tray connection member 340 of the tray 330 .", "In addition, on a lower surface of the cassette mounting plate 214 , a power supply unit 50 connected to the AC power supply is disposed.", "The power supply unit 50 and the long-side-direction rails are connected to each other through wire lines.", "[0089] When the tray connection member 340 and the cassette connection member 22 are connected to each other, power from the power supply unit 50 is supplied to the electronic cassette 20 through the long-side-direction rails 332 , the first slider, the short-side-direction rail 334 b, the second slider, and the tray connection member 340 .", "[0090] Next, operations of the radiographic imaging table 310 according to the third exemplary embodiment will be described.", "[0091] At the time of imaging, the test object 19 is loaded on the top board 12 .", "An operator mounts the electronic cassette 20 on the tray 330 .", "At this time, the cassette connection member 22 and the tray connection member 340 are not connected to each other.", "While checking the loaded position of the test object 19 on the top board 12 , the operator moves the tray 330 on which the electronic cassette 20 is mounted, to a corresponding position on the cassette mounting plate 214 .", "At this time, the movement on the cassette mounting plate 214 in the short-side direction is performed by sliding the tray 330 along the shot-side-direction rails 334 .", "The movement on the cassette mounting plate 214 in the long-side direction is performed by sliding the short-side-direction rails 334 to which the tray 330 is fixed, along the long-side-direction rails 332 .", "[0092] When the imaging is ended, the tray 330 remains in the position, or the tray 330 is moved to a position where the operator can easily handle it.", "In this state, the cassette connection member 22 is connected to the tray connection member 340 .", "As a result, power corresponding to the consumed power is supplied from the power supply unit 50 through the long-side-direction rail 332 , the first slider, the short-side-direction rail 334 b , the second slider, and the tray connection member 340 .", "[0093] In addition, when the long-side-direction rail 332 is connected not to the power supply unit 50 but to the console, the cassette connection member 22 is connected to the tray connection member 340 , so that the image data stored in the memory included in the electronic cassette 20 can be transmitted through the tray connection member 40 to the console.", "[0094] When the charging of the battery or the transmitting of data is ended, the cassette connection member 22 is disconnected from the tray connection member 40 .", "The electronic cassette 20 remains mounted on the tray 330 for the next imaging.", "[0095] In addition, the console is connected to a radiology information system (RIS, not shown) which collectively manages radiographic image information or others handled in the department of radiology of a hospital.", "The RIS is connected to a hospital information system (HIS, not shown) which collectively manages medical information of a hospital.", "Therefore, in the console, since power that is to be consumed by the electronic cassette 20 in the next imaging can be requested, the charging with the power corresponding to the to-be-consumed power can be controlled.", "[0096] In the radiographic imaging table according to the third exemplary embodiment, the charging of the electronic cassette and the transmitting of data can be performed without movement of the tray to the position of the connector disposed to a predetermined position, so that convenience can be improved.", "[0097] In addition, in the third exemplary embodiment, the short-side-direction rail 334 b is constructed with a conductive material.", "This construction is provided in order to simplify a connection mechanism between the tray connection member 340 , the second slider, and the short-side-direction rails, by taking into consideration the construction where the tray connection member 340 is provided to the short-side-direction rail 334 b .", "Alternatively, the short-side-direction rail 334 a may be constructed with a conductive material, and a wire line between the tray connection member 340 and the second slider may be disposed on a rear surface of the tray 330 .", "[0098] In addition, since the charging of the electronic cassette and the communication with an external device can be performed through the rails, there is no need for providing the connector that is provided in the first and second exemplary embodiments.", "However, the connector may also be provided so that the charging and communication through the rails as well as the charging and communication through connection of the tray to the connector can be performed.", "Due to the construction, various types of electronic cassettes can be adaptively implemented.", "[0099] Next, a radiographic imaging table according to a fourth exemplary embodiment will be described.", "The same elements as those of the radiographic imaging table according to the first to third exemplary embodiments are denoted by the same reference numerals, and the description thereof is omitted.", "[0100] As shown in FIG. 8 , in a radiographic imaging table 410 according to the fourth exemplary embodiment, a power transmitting coil 60 functioning as a primary coil for charging a battery of an electronic cassette in a non-contact manner is disposed in an inner portion of a cassette mounting plate 414 .", "The power transmitting coil 60 is connected to an AC power supply.", "In addition, the power transmitting coil 60 may be disposed on a lower surface of the cassette mounting plate 414 instead of an inner portion of the cassette mounting plate 414 .", "[0101] An electronic cassette 420 is provided with a power receiving coil 24 functioning as a secondary coil, a charging circuit 26 for rectifying an electromotive force generated in the power receiving coil 24 , and a battery 28 .", "[0102] Next, operations of the radiographic imaging table 410 according to the fourth exemplary embodiment will be described.", "[0103] At the time of imaging, the test object 19 is loaded on the top board 12 .", "An operator mounts the electronic cassette 420 on a tray 430 .", "While checking the loaded position of the test object 19 on the top board 12 , the operator moves the tray 430 on which the electronic cassette 420 is mounted, to a corresponding position on the cassette mounting plate 414 .", "At this time, the movement on the cassette mounting plate 414 in the short-side direction is performed by sliding the tray 430 along the short-side-direction rails 34 .", "The movement on the cassette mounting plate 414 in the long-side direction is performed by sliding the short-side-direction rails 34 to which the tray 430 is fixed, along the long-side-direction rails 32 .", "[0104] When the imaging is ended, the tray 430 is moved to a charging position where the power transmitting coil 60 is disposed.", "Magnetic field is generated from the power transmitting coil 60 applied with the AC power due to electromagnetic induction.", "The electromotive force induced to the power receiving coil 24 by the magnetic field is rectified by the charging circuit 26 , and the battery 28 is charged.", "When the charging of the battery 28 is ended, the tray 430 is moved from the charging position.", "[0105] In this manner, in the radiographic imaging table according to the fourth exemplary embodiment, since the battery of the electronic cassette can be charged in a non-contact manner, there is no need for connecting the battery to the connector at the time of charging.", "Accordingly, convenience can be improved.", "[0106] In addition, in the fourth exemplary embodiment, since the charging of the electronic cassette can be performed in a non-contact manner, there is no need for connection to the connector according to the first and second exemplary embodiments.", "However, a connector may be provided so as to perform communication with an external device or to perform the non-contact charging as well as the charging using a wire line connected to the connector.", "Due to the connector, various types of electronic cassettes can be adaptively implemented." ]
BACKGROUND OF THE INVENTION The present invention relates to an encoder and a printer using the same. Printers have various motors such as a paper feed motor for driving a feed roller that conveys print paper or a print object and a carriage motor for driving a carriage having a print head. DC motors are widely used as such motors to reduce noise. Printers having DC motors are equipped with an encoder composed of a scale having marks or slits disposed at specified intervals and a sensor that senses the marks or slits of the scale to output given signals to control the positions and speeds of the DC motors. For example, to control a paper feed motor, printers have a disc-shaped scale having multiple slits arranged at specified intervals and a sensor constructed to sandwich each slit between a light-emitting device and a light-receiving device. This type of scale is constructed to rotate with a feed roller. This type of sensor generally outputs two signals with a phase difference of 90° (for example, refer to Japanese Patent Publication No. 2001-232882). The motor is controlled by sensing changing points of the levels of the two signals output from the sensor. Among the optical encoders, an optical encoder that has graduations attached to a transparent glass substrate, and allows light reflected by the graduations to pass through a space between the graduations is known (see Japanese Patent Publication No. 2001-232882). In order to improve print quality, more accurate control is required for motors mounted to printers. For more accurate control, encoders have to output signals with higher resolution. There may be two methods for outputting higher-resolution signals from encoders: a method of increasing the diameter of the disc-shaped scale while maintaining the intervals of the slits and a method of decreasing the interval of the slits while maintaining the diameter of the scale. However, printers that need to be compact cannot have a large-diameter scale. To provide the space for the scale, the mechanical structure of the printers becomes complicated. In contrast, narrowing the interval between slits makes it difficult to manufacture the scale itself. Since an ink mist occurs in an apparatus using ink, such as a printer, if the interval between the graduations is narrow, a portion, through which light passes, may significantly change due to the ink mist, and thus control may be made unstable. SUMMARY OF THE INVENTION Accordingly, it is an object of the invention to provide an encoder that, even though wastes, such as an ink mist and so on, are attached to a scale, can prevent output signals from being made unstable. It is another object of the invention to provide a printer that can perform stable control with high accuracy. In order to achieve the above objects, according to the embodiment of the invention, there is provided an encoder comprising: a light emitter, operable to emit light; a scale comprising: a transparent main body which has a first face and the second face which is opposite to the first face; and a plurality of marks provided on at least one of the first face and the second face and formed at a predetermined interval, and adapted to reflect or intercept the light emitted from the light emitter; and a light detector operable to detect light reflected by the marks or light passing through a plurality of regions each of which is defined between adjacent ones of the marks, wherein the main body of the scale is formed with a plurality of through holes each of which connects the first face and the second face at one of the regions. The number of the through hole may be no more than one third of a total number of the regions. The number of the through hole may be no less than one tenth of a total number of the regions. The marks may be arranged on the first face in a first direction; and a width in the first direction of the through hole may be wider than the interval between the marks. The marks may be arranged on the first face in a first direction; and a width in the first direction of the through hole may be narrower than the interval between the marks. According to the invention, there is also provided a printer operable to print information on a printing medium comprising: a motor having a rotatable shaft; the encoder described above, wherein the scale is rotated in conjunction with the rotation of the shaft, and the light detector is operable to output a signal in accordance with the rotation of the scale; a controller, which controls the rotation of the shaft based on the signal output from the detector. The motor may be operable to rotate a roller adapted to feed the printing medium. BRIEF DESCRIPTION OF THE DRAWINGS The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein: FIG. 1 is a schematic perspective view of a printer according to a first embodiment of the invention; FIG. 2 is a schematic side view of a part for paper feeding of the printer of FIG. 1 ; FIG. 3 is a schematic diagram of a carriage of FIG. 1 and a sensor mechanism of a PF drive roller of FIG. 2 ; FIG. 4 is a block diagram showing the schematic structure of a controller of the printer and its peripherals; FIG. 5 is a block diagram showing the structure of a speed control unit for a PF motor in a DC unit of FIG. 4 ; FIG. 6 is a graph of an example of target speed curves drawn from a target speed table; FIG. 7 is an enlarged view of part Z in FIG. 6 ; FIG. 8 is a schematic diagram of a part related to the rotary encoder in FIG. 3 ; FIG. 9 is a front view of the rotary scale in FIG. 3 ; FIG. 10 is a side view of the rotary encoder in FIG. 3 ; FIGS. 11A to 11C are partial cross-sectional views showing a structure of a rotary scale of FIG. 3 . FIG. 12 is a schematic diagram showing the relationship between the board in FIG. 10 and its peripherals; FIG. 13 is an electric circuit diagram of the rotary encoder of FIG. 3 ; FIG. 14 shows signal waveforms generated by the rotary encoder; FIG. 15 shows signal waveforms generated by the rotary encoder when the rotating direction is changed; FIG. 16 is an electric circuit diagram of a rotary encoder according to a second embodiment of the invention; FIG. 17 shows signal waveforms generated by the rotary encoder according to the second embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS Hereinafter, an encoder and a printer using the same according to an embodiment of the invention will be described in detail with reference to the accompanying drawings. Moreover, the configuration of the printer will first be described, and the configuration of the encoder will be described, together with the description of the printer. In addition, as regards the description of the printer, a control method of a printer will also be described. First Embodiment (Schematic Structure of Printer) FIG. 1 is a schematic perspective view of a printer 1 according to a first embodiment of the invention; FIG. 2 is a schematic side view of a part for paper feeding of the printer 1 of FIG. 1 ; FIG. 3 is a schematic diagram of a carriage 3 of FIG. 1 and a sensor mechanism of a PF drive roller 6 of FIG. 2 . The printer 1 of the first embodiment is an inkjet printer that ejects ink to print paper P or a print object to thereby execute printing. Referring to FIGS. 1 to 3 , the printer 1 includes a carriage 3 having a print head 2 that ejects ink droplets; a carriage motor (CR motor) 4 that drives the carriage 3 in a main scanning direction MS; a paper feed motor (PF motor) 5 that feeds the print paper P in a subscanning direction SS; a PF drive roller 6 connected to the PF motor 5 ; a platen 7 opposed to the nozzle surface (the lower surface in FIG. 2 ) of the print head 2 ; and a chassis 8 on which these components are mounted. In this embodiment, the CR motor 4 and the PF motor 5 are both a direct-current (DC) motor. As shown in FIG. 2 , the printer 1 further includes a hopper 11 on which the print paper P before printing is placed; a paper feed roller 12 and a separation pad 13 for taking the print paper P placed on the hopper 11 into the printer 1 ; a paper sensor 14 that senses the passage of the print paper P taken into the printer 1 from the hopper 11 ; and a delivery drive roller 15 that ejects the print paper P from the printer 1 . The carriage 3 can be moved in the main scanning direction MS by a guide shaft 17 supported by a support frame 16 fixed to the chassis 8 and a timing belt 18 . Specifically, the timing belt 18 runs between a pulley 19 and a pulley 20 under a specified tension, the pulley 19 being partly secured to the carriage 3 and being fixed to the output shaft of the CR motor 4 , and the pulley 20 being rotatably fixed to the support frame 16 . The guide shaft 17 sidably holds the carriage 3 so as to guide the carriage 3 in the main scanning direction MS. The carriage 3 further has an ink cartridge 21 in addition to the print head 2 , in which various inks to be supplied to the print head 2 are housed. The paper feed roller 12 connects to the PF motor 5 with a gear (not shown), and is driven by the PF motor 5 . As shown in FIG. 2 , the hopper 11 is a plate-like member on which the print paper P can be placed, which can be oscillated about a rotation shaft 22 at the top by a cam mechanism (not shown). The oscillation by the cam mechanism springily brings the lower end of the hopper 11 into and out of pressure contact with the paper feed roller 12 . The separation pad 13 is made of a high-friction member and is opposed to the paper feed roller 12 . As the paper feed roller 12 rotates, the surface of the paper feed roller 12 and the separation pad 13 come into pressure contact with each other. Accordingly, when the paper feed roller 12 rotates, the uppermost of the print paper P placed on the hopper 11 passes through the contact between the surface of the paper feed roller 12 and the separation pad 13 toward the delivery side; the second and later upper print paper P are stopped by the separation pad 13 . The PF drive roller 6 connects to the PF motor 5 directly or with a gear (not shown). As shown in FIG. 2 , the printer 1 further has a PF driven roller 23 that feeds the print paper P with the PF drive roller 6 . The PF driven roller 23 is rotatably held at the delivery side of a driven-roller holder 24 that is rotatable about a rotation shaft 25 . The driven-roller holder 24 is urged counterclockwise (in the drawing) by a spring (not shown) so that the PF driven roller 23 is constantly urged to the PF drive roller 6 . When the PF drive roller 6 is driven, the PF driven roller 23 also rotates with the PF drive roller 6 . As shown in FIG. 2 , the paper sensor 14 is composed of a sensing lever 26 and a sensor 27 , and is disposed in the vicinity of the driven-roller holder 24 . The sensing lever 26 is rotatable about a rotation shaft 28 . When the print paper P completes passing below the sensing lever 26 from the passing state shown in FIG. 2 , the sensing lever 26 turns counterclockwise. When the sensing lever 26 turns, the light from a light-emitting portion of the sensor 27 toward a light-receiving portion is interrupted to thereby sense the passage of the print paper P. The delivery drive roller 15 is disposed on the delivery side of the printer 1 , and connects to the PF motor 5 with a gear (not shown). As shown in FIG. 2 , the printer 1 further includes a delivery driven roller 29 for delivering the print paper P together with the delivery drive roller 15 . Like the PF driven roller 23 , the delivery driven roller 29 is also constantly urged toward the delivery drive roller 15 by a spring (not shown). When the delivery drive roller 15 is driven, the delivery driven roller 29 also rotates with the delivery drive roller 15 . Referring to FIG. 3 , the printer 1 further includes a linear encoder 33 having a linear scale 31 and a sensor 32 for determining the rotational position of the CR motor 4 (the position of the carriage 3 in the main scanning direction MS) and the rotational speed of the CR motor 4 (the speed of the carriage 3 ); and a rotary encoder 36 having a rotary scale 34 and a sensor 35 for determining the rotational position of the PF motor 5 in the subscanning direction SS (the position of the print paper P in the subscanning direction SS) and the rotational speed of the PF motor 5 (the feeding speed of the print paper P). The linear scale 31 is shaped in a long straight line, and is mounted to the support frame 16 in parallel with the main scanning direction MS. The linear scale 31 has marks 31 a at specified intervals. The sensor 32 has a light-emitting device and a light-receiving device (not shown), and is mounted to the carriage 3 . The linear encoder 33 outputs a specified output signal in such a manner that the light emitted from the light-emitting device toward the linear scale 31 is reflected by the marks 31 a , and the light-receiving device receives the reflected light. Unlike a rotary scale 34 to be described below, the linear scale 31 does not have a main body portion formed of a transparent member. However, the linear scale 31 may have a main body portion formed of a transparent member. The rotary scale 34 is shaped like a disc, and is mounted to the PF drive roller 6 so as to rotate therewith. Specifically, when the PF drive roller 6 makes a turn, the rotary scale 34 also makes a turn. The sensor 35 is fixed to the chassis 8 with a bracket (not shown). Alternatively, the rotary scale 34 may be connected to the PF drive roller 6 with a gear or the like. However, mounting the rotary scale 34 directly to the PF drive roller 6 so as to rotate therewith allows one-to-one correspondence of the rotation amount of the rotary scale 34 and that of the PF drive roller 6 without errors such as play at the engaging portion of a gear. The details of the structure of the rotary encoder 36 will be described later. (Schematic Structure of Controller of Printer) FIG. 4 is a block diagram showing the schematic structure of a controller 37 of the printer 1 and its peripherals. As shown in FIG. 4 , the controller 37 includes a bus 38 , a CPU 39 , a ROM 40 , a RAM 41 , a character generator (CG) 42 , a nonvolatile memory 43 , an interface (I/F) dedicated circuit 44 , a DC unit 45 , a PF-motor drive circuit 46 , a CR-motor drive circuit 47 , a head drive circuit 48 , and an application-specific integrated circuit (ASIC) 51 . The controller 37 is configured such that the CPU 39 and the ASIC 51 receive output signals from the linear encoder 33 and the rotary encoder 36 . The CPU 39 performs operations for executing the control programs of the printer 1 stored in the ROM 40 and the nonvolatile memory 43 and other necessary operations. The ROM 40 stores control programs for controlling the printer 1 and data necessary for processing. For example, the ROM 40 stores a target speed table that contains target rotational speeds for the rotational positions of the CR motor 4 and the PF motor 5 . The RAM 41 temporarily stores programs that the CPU 39 is executing and data during operation. The CG 42 stores dot patterns expanded corresponding to print signals input to the I/F dedicated circuit 44 . The nonvolatile memory 43 stores various data that needs to be stored after the printer 1 is turned off. The I/F dedicated circuit 44 has a parallel interface circuit, which can receive print signals sent from a computer 50 via a connector 49 . The ASIC 51 controls the CR motor 4 and the PF motor 5 via the DC unit 45 , and controls the print head 2 via the head drive circuit 48 . The DC unit 45 is a control circuit for controlling the speed of the DC motor. The DC unit 45 performs various operations for controlling the speed of the CR motor 4 and the PF motor 5 according to the control instruction sent from the CPU 39 and signals output from the ASIC 51 via the I/F dedicated circuit 44 , and outputs motor control signals to the PF-motor drive circuit 46 and the CR-motor drive circuit 47 on the basis of the calculations. The PF-motor drive circuit 46 controls the driving of the PF motor 5 according to the motor control signal from the DC unit 45 . This embodiment adopts a pulse width modulation (PWM) control to control the PF motor 5 . Thus the PF-motor drive circuit 46 outputs a PWM driving signal. Similarly, the CR-motor drive circuit 47 controls the CR motor 4 in response to the motor control signal from the DC unit 45 . The head drive circuit 48 drives the nozzles of the print head 2 under the control instruction sent from the CPU 39 or the ASIC 51 via the I/F dedicated circuit 44 . The bus 38 is a signal line that connects the foregoing components of the controller 37 . The bus 38 interconnects the CPU 39 , the ROM 40 , the RAM 41 , the CG 42 , the nonvolatile memory 43 , and the I/F dedicated circuit 44 to enable exchange of data. (Structure of PF-Motor Speed Control Unit) FIG. 5 is a block diagram showing the structure of a speed control unit 53 for the PF motor 5 in the DC unit 45 ; FIG. 6 is a graph of examples of a target speed curve drawn from the target speed table stored in the ROM 40 of FIG. 4 ; and FIG. 7 is an enlarged view of part Z in FIG. 6 . As has been described, the DC unit 45 serves as a control circuit for controlling the speed of the CR motor 4 and the PF motor 5 . The structure of the speed control unit 53 for the PF motor 5 in the DC unit 45 will be described hereinbelow. A speed control unit for the CR motor 4 in the DC unit 45 has the same structure as the speed control unit 53 . As shown in FIG. 5 , the speed control unit 53 includes a location-deviation operating section 56 , a target-speed operating section 57 , a speed-deviation operating section 58 , a comparing element 59 , an integrator element 60 , a differentiating element 61 , an adding section 62 , and a D/A converter 63 . In other words, this embodiment employs a proportional, integral, and derivative (PID) control to control the PF motor 5 , in which the present rotational speed of the PF motor 5 is converged to a target rotational speed by a combination of comparing control, integral control, and derivative control. The location-deviation operating section 56 and the speed-deviation operating section 58 receive specified signals from the ASIC 51 . As has been described, the ASIC 51 receives a signal output from the rotary encoder 36 . The ASIC 51 outputs a present-rotational-position signal (a print-paper-P present-position signal) Pc corresponding to the present rotational position of the PF motor 5 responding to an output signal from the rotary encoder 36 , and a present-rotational-speed signal (a print-paper-P present-feed-speed signal) Vc corresponding to the present rotational speed of the PF motor 5 responding to an output signal from the rotary encoder 36 . The location-deviation operating section 56 receives the present-rotational-position signal Pc and a target-stop-position signal Pt corresponding to the next stop position of the print paper P in the subscanning direction SS. The location-deviation operating section 56 calculates and outputs a location-deviation signal dP corresponding to location deviation that is the difference between the input present-position signal Pc and the target-stop-position signal Pt. The target-stop-position signal Pt is input from the CPU 39 . The target-speed operating section 57 receives the location-deviation signal dP. The target-speed operating section 57 calculates and outputs a target-rotational-speed signal (a print-paper-P target-feed-speed signal) Vt corresponding to the target rotational speed of the PF motor 5 on the basis of the input location-deviation signal dP. More specifically, the target-speed operating section 57 reads a target-rotational-speed signal Vt corresponding to the location-deviation signal dP from the target speed table stored in the ROM 40 and outputs it. The solid line of FIG. 6 shows an example of a target speed curve created from the target speed table store in the ROM 40 . The target speed curve created from the target speed table has an accelerating region, a constant-speed region, and a decelerating region toward a target stop position X. The target speed table provides the target-rotational-speed signal Vt so as to correspond to the location-deviation signal dP in a specified range of values. Accordingly, the target speed curve is actually in the form of steps, as shown in FIG. 7 , so that the target rotational speed is held constant even if the location-deviation signal dP varies slightly. Rotational speed in the constant-speed region depends on print mode. For example, the ROM 40 also stores target-speed tables corresponding to the dotted line and the two-dot chain line in FIG. 6 . The ROM 40 also stores a target-speed table corresponding to various target stop positions. The speed-deviation operating section 58 receives the target-rotational-speed signal Vt and the present-rotational-speed signal Vc. The speed-deviation operating section 58 outputs a speed deviation signal dV that is the difference between the input target-rotational-speed signal Vt and the present-rotational-speed signal Vc. The speed deviation signal dV output from the speed-deviation operating section 58 is input to the comparing element 59 , the integrator element 60 , and the differentiating element 61 . The comparing element 59 , the integrator element 60 , and the differentiating element 61 respectively output a comparing-control-value signal QP, an integral-control-value signal QI, and a derivative-control-value signal QD calculated from the input speed deviation signal dV by a specified calculating expression. The adding section 62 receives the comparing-control-value signal QP output from the comparing element 59 , the integral-control-value signal QI output from the integrator element 60 , and the derivative-control-value signal QD output from the differentiating element 61 . The adding section 62 adds the control value signals QP, QI, and QD to output a PID-control-value signal □Q that is digital data, to the D/A converter 63 . The D/A converter 63 converts the digital PID-control-value signal □Q to analog data, and outputs it. The analog data output from the D/A converter 63 is input to the PF-motor drive circuit 46 as a motor control signal. (Structure of Rotary Encoder) FIG. 8 is a schematic diagram of a part related to the rotary encoder 36 of FIG. 3 ; FIG. 9 is a front view of the rotary scale 34 in FIG. 3 ; FIG. 10 is a side view of the sensor 35 in FIG. 3 ; FIGS. 11A to C are partial cross-sectional views showing a structure of the rotary scale of FIG. 3 ; FIG. 12 is a schematic diagram showing the relationship between a board 68 disposed to the sensor 35 shown in FIG. 10 and its peripherals. FIG. 13 is an electric circuit diagram of the rotary encoder 36 of FIG. 3 ; and FIG. 14 shows signal waveforms generated by the rotary encoder 36 by the normal rotation of the rotary scale 34 , wherein (A) shows level signal waveforms amplified by a first amplifier 74 and a third amplifier 76 shown in FIG. 13 ; (B) shows a signal waveform output from a first-differential-signal generating circuit 78 shown in FIG. 13 ; (C) shows level signal waveforms amplified by a second amplifier 75 and a fourth amplifier 77 shown in FIG. 13 ; (D) shows a signal waveform output from a second-differential-signal generating circuit 79 shown in FIG. 13 ; (E) shows a signal waveform output from an exclusive OR circuit 80 shown in FIG. 13 ; (F) shows a signal waveform output from a row-B-signal generating circuit 71 shown in FIG. 13 ; (G) is a signal waveform output from a row-C-signal generating circuit 72 shown in FIG. 13 ; and (H) is a signal waveform output from a row-D-signal generating circuit 73 shown in FIG. 13 . FIG. 15 shows signal waveforms generated by the rotary encoder 36 when the rotating direction of the rotary scale 34 is changed, wherein (A) shows a signal waveform output from the exclusive OR circuit 80 shown in FIG. 13 ; (B) shows a signal waveform output from the row-B-signal generating circuit 71 shown in FIG. 13 ; (C) shows a signal waveform output from the row-C-signal generating circuit 72 shown in FIG. 13 ; and (D) shows a signal waveform output from the row-D-signal generating circuit 73 shown in FIG. 13 . The rotary scale 34 is, for example, a plastic thin plate and is formed in a disc shape shown in FIG. 9 . As shown in FIG. 11A , the rotary scale 34 has a main body portion 34 a formed of polyethylene terephthalate (PET), and marks 34 b serving as graduations. The main body portion 34 a is transparent so as to allow light to pass therethrough. In this embodiment, the thickness of the main body portion 34 a is significantly thin, for example, 180 μm. Moreover, in FIGS. 11A to 11C , the marks 34 b are shown thick, but are actually set in a range of several μm to 20 μm. The marks 34 b are formed by attaching a non-transmissive material to a surface of the main body portion 34 a using printing or deposition. For this reason, light does not pass through the marks 34 b. In the rotary scale 34 , 180 slits 65 , each forming the space between the marks 34 b , are formed in a direction perpendicular to the paper of FIG. 9 . The 180 slits 65 are arranged at the same positions of the rotary scale 34 in a radial direction at regular angular intervals. That is, the 180 slits 65 are arranged at the regular angular intervals along an outer circumference of the rotary scale 34 . An interval between adjacent slits 65 and the width of each of the slits 65 in an arrangement direction of the slits 65 (a circumferential direction of the rotary scale 34 ) are substantially equal to each other. In FIG. 9 , for convenience, the slits 65 are displayed in the circumferential direction on a magnified scale, but the 180 slits 65 are actually formed in one round, and thus the width of each of the slits 65 in the circumferential direction is made significantly small. A through hole 34 c that has a width W 2 equal to the width W 1 of the slit 65 is formed to correspond to the slit 65 for every three slits 65 among the slits 65 . The through hole 34 c prevents the occurrence of diffused reflection or refraction due to a decrease in the amount of light passing through the slit 65 caused by the ink mist attached to the slit 65 . As shown in FIG. 11B , the rotary scale 34 may have the through hole 34 c that has a width W 3 larger than the width W 1 of the slit 65 . Further, as shown in FIG. 11B , the number of through holes 34 c to be provided may be a fourth of all the slits 65 , not a third of all the slits 65 (see FIG. 11A ). If the width W 3 of the through hole 34 c becomes larger than the width W 1 of the slit 65 , light 34 c passing through the periphery of the mark 34 b rarely enter the main body portion 34 a . If light 34 d enters the main body portion 34 a , light 34 d enters a deep part of the main body portion 34 a due to a refractive index when incident. Then, a light-receiving range of a light-receiving element 69 , which is described below, changes by the position of the light-receiving element 69 , and thus the output signals are rarely stabilized. The structure shown in FIG. 11B does not have such problems. The rotary scale 34 may have a structure shown in FIG. 11C . That is, the through hole 34 c may have a width W 4 smaller than the width W 1 of the slit 65 . With this configuration, the strength of the main body portion 34 a can be kept. Light passing through the periphery of a boundary portion 34 e between the mark 34 b and the slit 65 is incident on the main body portion 34 a from the top surface. Therefore, light that is received by the light-receiving element 69 can be stabilized, and a light-receivable region can be prevented from being expanded. Preferably, the through holes 34 c are respectively provided to correspond to slits 65 of a third to a tenth of all the slits 65 . If the through holes are respectively provided between marks of a tenth or more of all the marks, more wastes pass through the scale, and thus the wastes are rarely attached to the rotary scale 34 . Meanwhile, if the through holes 34 c are respectively provided between marks of a third or less of all the marks, the strength of the rotary scale 34 can be kept. Moreover, in view of strength balance, the through holes 34 c are preferably provided at predetermined regular intervals. The rotary scale 34 rotates with the PF drive roller 6 , as described above. That is, when the PF drive roller 6 makes a turn, the rotary scale 34 also makes a turn. When the peripheral length of the PF drive roller 6 is one inch, the resolution of the single rotary scale 34 is 180 (=1 in./180) dpi. The rotary scale 34 may be connected to the PF drive roller 6 with a gear or the like, as described above, so that, e.g., the rotary scale 34 makes two turns when the PF drive roller 6 makes a turn. Referring to FIG. 10 , the sensor 35 has a substantially rectangular parallelepiped housing. The sensor 35 has a recess 66 from one side (the left side in FIG. 10 ) toward the center of the housing. A light-emitting element 67 or a light emitter is disposed on one of two opposing surfaces (two vertically opposing surfaces in FIG. 10 ) of the recess 66 , while a board 68 is disposed on the other surface. The board 68 has a plurality of light-receiving elements 69 or sensing elements (see FIG. 12 ), so that the portion of the board 68 serves as the photoreceiver (sensing portion) of the sensor 35 . The sensor 35 holds part of the outer periphery of the rotary scale 34 in the recess. Thus the outer periphery of the rotary scale 34 , that is, the portion of the rotary scale 34 where the slits 65 are formed is located between the light-emitting element 67 and the light-receiving elements 69 . The light-emitting element 67 is, for example, a light-emitting diode, which emits light having a good straight-forwarding performance. Referring to FIG. 12 , the board 68 has the light-receiving elements 69 arranged in four rows along the rotating direction of the rotary scale 34 . Hereinafter, the four rows of the light-receiving elements 69 are referred to as rows A, B, C, and D from the top of FIG. 12 . The light-receiving elements 69 are, for example, a photodiode, which output signals of a level according to the amount of received light. Moreover, in FIG. 12 , the main body portion 34 a formed of the transparent member is not shown. Assuming that the light-emitting element 67 emits parallel rays onto the board 68 , as shown in FIG. 12 , light and dark portions (light and shade) are formed on the surface of the board 68 at the same intervals as that of the slits 65 along the outer periphery of the rotary scale 34 . Specifically, the portions of the board 68 corresponding to the slits 65 are irradiated with the light from the light-emitting element 67 . The portions of the board 68 corresponding to the interval between the slits 65 of the rotary scale 34 are shielded from the light of the light-emitting element 67 . Thus, one cycle of the light and dark portions formed on the surface of the board 68 (hereinafter, referred to as a light and shade cycle T) corresponds to the arrangement pitch of the slits 65 of the rotary scale 34 . In other words, when the light-emitting element 67 irradiates the board 68 with parallel rays, the light and shade cycle T formed on the surface of the board 68 is the same as the pitch of the slits 65 . Accordingly, when the rotary scale 34 rotates at equal speed, the light and shade cycle T formed on the surface of the board 68 becomes substantially constant. When the light emitted from the light-emitting element 67 is not parallel rays, or is diffused light, the light and shade cycle T formed on the board 68 is narrow at the portion of the board 68 closest to the light-emitting element 67 , and is wider with an increasing distance from the light-emitting element 67 . Thus, in that case, even when the rotary scale 34 rotates at equal speed, the light and shade cycle T does not become constant. The light-receiving elements 69 in rows A to D are each disposed over a plurality of light and shade cycles T (three cycles in FIG. 12 ) of the board 68 . FIG. 12 shows the arrangement relationship among the light-receiving elements 69 in the case where the light from the light-emitting element 67 is parallel light. Each of the light-receiving elements 69 has a light-receiving surface of a size approximately one quarter of the light and shade cycle T formed on the board 68 . In other words, each of the light-receiving elements 69 in each row has a size equal to one quarter of the light and shade cycle T. As shown in FIG. 11 , a plurality of sets of four light-receiving elements 69 of a first light-receiving element A 1 ( 69 ) (B 1 ( 69 ), C 1 ( 69 ), or D 1 ( 69 )); a second light-receiving element A 2 ( 69 ) (B 2 ( 69 ), C 2 ( 69 ), or D 2 ( 69 )); a third light-receiving element A 3 ( 69 ) (B 3 ( 69 ), C 3 ( 69 ), or D 3 ( 69 )); a fourth light-receiving element A 4 ( 69 ) (B 4 ( 69 ), C 4 ( 69 ), or D 4 ( 69 )) corresponding to the light and shade cycle T is disposed in each of rows A to D from the left in the drawing. The light-receiving elements 69 in four rows are disposed with a slight displacement with each other in the rotating direction of the rotary scale 34 . More specifically, the four rows of light-receiving elements 69 are displaced one sixteenth of the light and shade cycle T with each other in the rotating direction of the rotary scale 34 . Referring to FIG. 12 , when the PF motor 5 rotates in the normal direction (in the direction in which the print paper P is fed to the delivery side) (when the rotary scale 34 rotates in the normal direction), the rotary scale 34 rotates from the left to the right of the drawing. In this case, row B is formed in a position shifted to the right of the light-receiving elements 69 in row A by one sixteenth of the light and shade cycle T. Row C is formed in a position shifted to the right of the light-receiving elements 69 in row A by two sixteenths of the light and shade cycle T. Row D is formed in a position shifted to the right of the light-receiving elements 69 in row A by three sixteenths of the light and shade cycle T. In other words, referring to FIG. 12 , for example, the light-receiving element A 1 ( 69 ) at the left end of row A, the light-receiving element B 1 ( 69 ) at the left end of row B, the light-receiving element C 1 ( 69 ) at the left end of row C, and the light-receiving element D 1 ( 69 ) at the left end of row D are displaced with each other in that order by one sixteenth of the light and shade cycle T (one cycle of light and shade) along the moving direction of the light and shade formed by the slits 65 . When the rotary scale 34 rotates with the PF drive roller 6 , the slits 65 move between the light-emitting element 67 and the light-receiving elements 69 of the sensor 35 . As the slits 65 moves, the light-receiving elements 69 output signals at a level depending on the amount of received light. More specifically, the light-receiving elements 69 corresponding to the slits 65 output high-level signals, while the light-receiving elements 69 corresponding to the interval between the slits 65 output low-level signals. Thus the light-receiving elements 69 output signal at a level varied in a cycle depending on the moving speed of the slits 65 . Referring to FIG. 13 , the sensor 35 that configures the rotary encoder 36 includes a row-A-signal generating circuit 70 or first signal generating means having a plurality of row-A light-receiving elements 69 , a row-B-signal generating circuit 71 or second signal generating means having a plurality of row-B light-receiving elements 69 , a row-C-signal generating circuit 72 or third signal generating means having a plurality of row-C light-receiving elements 69 , and a row-D-signal generating circuit 73 or fourth signal generating means having a plurality of row-D light-receiving elements 69 . The row-A-signal generating circuit 70 includes the row-A light-receiving elements 69 , the first to fourth amplifiers 74 , 75 , 76 , and 77 , the first differential-signal generating circuit 78 , the second differential-signal generating circuit 79 , and an exclusive OR circuit 89 . As shown in FIG. 12 , a plurality of sets of four light-receiving elements 69 , the first light-receiving element A 1 ( 69 ), the second light-receiving element A 2 ( 69 ), the third light-receiving element A 3 ( 69 ), and the fourth light-receiving element A 4 ( 69 ) corresponding to the light and shade cycle T is arranged in row A. The first amplifier 74 connects to the row-A first light-receiving elements A 1 ( 69 ) in parallel. The first light-receiving elements A 1 ( 69 ) each output a signal at a level responsive to their respective received light amount. The first amplifier 74 amplifies the level signals output from the first light-receiving elements A 1 ( 69 ). Similarly, the second amplifier 75 connects to the A-row second light-receiving elements A 2 ( 69 ) in parallel. The second amplifier 75 amplifies the level signals output from the second light-receiving elements A 2 ( 69 ), and outputs them. The third amplifier 76 connects to the row-A third light-receiving elements A 3 ( 69 ) in parallel. The third amplifier 76 amplifies the level signals output from the third light-receiving elements A 3 ( 69 ), and outputs them. The fourth amplifier 77 connects to the row-A fourth light-receiving elements A 4 ( 69 ) in parallel. The fourth amplifier 77 amplifies the level signals output from the fourth light-receiving elements A 4 ( 69 ), and outputs them. As shown in FIG. 12 , the first light-receiving elements A 1 ( 69 ) and the third light-receiving elements A 3 ( 69 ) are each formed on the board 68 in such a manner as to be displaced a half of the light and shade cycle T with respect to each other. Accordingly, as shown in FIG. 14(A) , the signal waveform amplified by the first amplifier 74 and the signal waveform amplified by the third amplifier 76 are displaced a half of the light and shade cycle T with respect to each other. Similarly, the second light-receiving elements A 2 ( 69 ) and the fourth light-receiving elements A 4 ( 69 ) are each formed on the board 68 in such a manner as to be displaced a half of the light and shade cycle T with respect to each other. Accordingly, as shown in FIG. 14(C) , the signal waveform amplified by the second amplifier 75 and the signal waveform amplified by the fourth amplifier 77 are displaced a half of the light and shade cycle T with respect to each other. The time of the cycle TL of the signal waveforms output from the amplifiers 74 , 75 , 76 , and 77 is the same as that of the light and shade cycle T. The first amplifier 74 and the third amplifier 76 output amplified level signals to the first-differential-signal generating circuit 78 . The level signal amplified by the first amplifier 74 is input to a noninverting input terminal of the first-differential-signal generating circuit 78 , while the level signal amplified by the first-differential-signal generating circuit 78 is input to an inverting input terminal of the first-differential-signal generating circuit 78 . When the level of the signal input to the noninverting input terminal (the signal output from the first amplifier 74 ) is higher than that of the signal input to the inverting input terminal (the signal output from the third amplifier 76 ), the first-differential-signal generating circuit 78 outputs a high-level signal; when the level of the signal input to the noninverting input terminal is lower than that of the signal input to the inverting input terminal, the first-differential-signal generating circuit 78 outputs a low-level signal. Thus the first-differential-signal generating circuit 78 outputs a digital-waveform signal. In other words, as shown in FIG. 14(B) , the first-differential-signal generating circuit 78 outputs a digital-waveform signal with a duty of approximately 50% substantially in the same cycle as that output from the third light-receiving element A 3 ( 69 ). The second amplifier 75 and the fourth amplifier 77 output amplified level signals to the second-differential-signal generating circuit 79 . The level signal amplified by the second amplifier 75 is input to a noninverting input terminal of the second-differential-signal generating circuit 79 , while the level signal amplified by the fourth amplifier 77 is input to an inverting input terminal of the second-differential-signal generating circuit 79 . When the level of the signal input to the noninverting input terminal (the signal output from the second amplifier 75 ) is higher than that of the signal input to the inverting input terminal (the signal output from the fourth amplifier 77 ), the second-differential-signal generating circuit 79 outputs a high-level signal; when the level of the signal input to the noninverting input terminal is lower than that input to the inverting input terminal, the second-differential-signal generating circuit 79 outputs a low-level signal. Thus the second-differential-signal generating circuit 79 outputs a digital-waveform signal. In other words, as shown in FIG. 14(D) , the second-differential-signal generating circuit 79 outputs a digital-waveform signal with a duty of approximately 50% substantially in the same cycle as that of the level signal output from the fourth light-receiving element A 4 ( 69 ). As shown in FIG. 12 , the first light-receiving elements A 1 ( 69 ) and the second light-receiving elements A 2 ( 69 ) are each formed on the board 68 in such a manner as to be displaced a quarter of the light and shade cycle T with respect to each other. Accordingly, the output signal of the first-differential-signal generating circuit 78 shown in FIG. 14(B) and the output signal of the second-differential-signal generating circuit 79 shown in FIG. 14 (D) are displaced a quarter of the light and shade cycle T with respect to each other. The output signal of the first-differential-signal generating circuit 78 and the output signal of the second-differential-signal generating circuit 79 are input to the exclusive OR circuit 80 . When both of the two inputs are on a high level or a low level, the exclusive OR circuit 80 outputs a low-level signal; when only one of the two inputs is on a high level, it outputs a high-level signal. Specifically, as shown in FIG. 14(E) , the exclusive OR circuit 80 outputs a signal S 1 with a cycle about a half of that of the level signal of the light-receiving elements 69 . When the rotating direction of the rotary scale 34 is changed at time t 0 , the exclusive OR circuit 80 outputs the signal S 1 shown in FIG. 15(A) . The output signal of the exclusive OR circuit 80 is output from an output terminal 81 of the rotary encoder 36 . The output signal of the exclusive OR circuit 80 (the output signal of the row-A-signal generating circuit 70 ) S 1 corresponds to a first output signal. Since the internal structures of the row-B-signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 are the same as that of the row-A-signal generating circuit 70 , drawings thereof and descriptions will be omitted. The row-B signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 respectively output signals S 2 , S 3 , and S 4 with a cycle approximately a half of the level signal of the light-receiving elements 69 shown in FIGS. 14(F) , 14 (G), and 14 (H). When the rotating direction of the rotary scale 34 is changed at time t 0 , the row-B-signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 respectively output signals S 2 , S 3 , and S 4 shown in FIGS. 15(B) , 15 (C), and 15 (D). As has been described, the light-receiving elements 69 in row B are displaced to the right of the light-receiving elements 69 in row A by a sixteenth of the light and shade cycle T. The light-receiving elements 69 in row C are displaced to the right of the light-receiving elements 69 in row A by two sixteenths of the light and shade cycle T. The light-receiving elements 69 in row D are displaced to the right of the light-receiving elements 69 in row A by three sixteenths of the light and shade cycle T. Therefore, as shown in FIGS. 14(E) to 14(H) , when the rotary scale 34 rotates in the normal direction, the phase of the output signal S 2 of the row-B-signal generating circuit 71 is basically delayed a sixteenth of the light and shade cycle T behind the phase of the output signal S 1 of the row-A-signal generating circuit 70 . The phase of the output signal S 3 of the row-C-signal generating circuit 72 is basically delayed two sixteenths of the light and shade cycle T behind the phase of the output signal S 1 of the row-A-signal generating circuit 70 . The phase of the output signal S 4 of the row-D-signal generating circuit 73 is basically delayed three sixteenths of the light and shade cycle T behind the phase of the output signal S 1 of the row-A-signal generating circuit 70 . As shown in FIG. 13 , the output signal S 2 of the row-B-signal generating circuit 71 is output from an output terminal 82 of the rotary encoder 36 ; the output signal S 3 of the row-C-signal generating circuit 72 is output from an output terminal 83 of the rotary encoder 36 ; and the output terminal S 4 of the row-D-signal generating circuit 73 is output from an output terminal 84 of the rotary encoder 36 . In other words, the rotary encoder 36 has four output terminals 81 , 82 , 83 , and 84 . The output signal S 2 of the row-B-signal generating circuit 71 corresponds to a second output signal; the output signal S 3 of the row-C-signal generating circuit 72 corresponds to a third output signal; and the output signal S 4 of the row-D-signal generating circuit 73 corresponds to a fourth output signal. Referring back to FIG. 8 , the four output terminals 81 , 82 , 83 , and 84 connect to the controller 37 with four signal lines 86 , 87 , 88 , and 89 , respectively. (Method for Controlling Printer) The printer 1 with this arrangement reciprocates the carriage 3 driven by the CR motor 4 in the main scanning direction MS while feeding the print paper P taken from the hopper 11 into the printer 1 with the paper feed roller 12 and the separation pad 13 in the subscanning direction SS with the PF drive roller 6 driven by the PF motor 5 . While the carriage 3 is reciprocating, the print head 2 jets out ink drops to print on the print paper P. Upon completion of printing to the print paper P, the print paper P is delivered to the outside of the printer 1 with the delivery drive roller 15 and so on. When the print paper P is fed in the subscanning direction SS, the PF motor 5 rotates the PF drive roller 6 . On rotation of the PF drive roller 6 , the rotary scale 34 rotates with the PF drive roller 6 . On rotation of the rotary scale 34 , the rotary encoder 36 outputs the four signals S 1 , S 2 , S 3 , and S 4 . The output signals S 1 , S 2 , S 3 , and S 4 are input to a predetermined processing circuit (e.g., the ASIC 51 ) of the controller 37 . To control the PF motor 5 and so on, the rotational position and speed of the PF motor 5 are determined from the output signals S 1 , S 2 , S 3 , and S 4 of the rotary encoder 36 . A method for determining the rotational position and speed and rotating direction of the PF motor 5 will be described in sequence. A method for determining the rotational position of the PF motor 5 will first be described. The rotational position of the PF motor 5 is determined using edges E 1 , E 2 , E 3 , and E 4 at which the levels of the output signals S 1 , S 2 , S 3 , and S 4 , shown in FIGS. 14(E) to 14(H) , change (rise and fall). In other words, the rotational position of the PF motor 5 is determined by counting the number of the edges E 1 , E 2 , E 3 , and E 4 output from the rotary encoder 36 . The four output signals S 1 , S 2 , S 3 , and S 4 are expressed as output signals S hereinbelow, if collectively expressed. The four edges E 1 , E 2 , E 3 , and E 4 are expressed as edges E, if collectively expressed. When the PF motor 5 rotates in both of the normal and reverse directions, the rotational position of the PF motor 5 is determined from the determination on the rotating direction, to be described later, and the number of the edges E. Here a case where the PF motor 5 rotates only in one direction will be described. For example, where the PF motor 5 rotates in the normal direction, the edges E are input when the edges E 1 , E 2 , E 3 , and E 4 are output from the rotary encoder 36 in that order, as shown in FIGS. 14(E) to 14(H) , so that the rotational position of the PF motor 5 can be determined appropriately by a predetermined processing circuit (e.g., the ASIC 51 ) of the controller 37 . The cycle of the output signals S is approximately a half of that of the level signal of the light-receiving elements 69 . The signals S 1 , S 2 , S 3 , and S 4 are basically sequentially output with a phase difference of one sixteenth of the light and shade cycle T. Accordingly, when the rotational speed of the PF motor 5 increases to output high-frequency signals S from the rotary encoder 36 , a phenomenon in which the edges E 1 , E 2 , E 3 , and E 4 are not output in that order, e.g., two edges E overlapped or the order of the output edges E are reversed, because of the characteristic of the electrical circuit of the rotary encoder 36 . To determine the rotational position of the PF motor 5 using the four output signals S under such a phenomenon due to the high-frequency signals, the structure of a processing circuit for determining the rotational position is complicated or the processing load on the processing circuit is increased. Accordingly, in this embodiment, when the PF motor 5 rotates at or below a specified rotational speed at which the foregoing problems due to high-frequency signals do not occur, a predetermined processing circuit determines the rotational position of the PF motor 5 using all the four output signals S. That is, the processing circuit determines the rotational position of the PF motor 5 by counting the number of the edges E of each of the four output signals S. On the other hand, when the PF motor 5 rotates at or over a specified rotational speed at which the foregoing problems due to high-frequency signals can occur, a predetermined processing circuit determines the rotational position of the PF motor 5 using the two output signals S 1 and D 3 or the two output signals S 2 and S 4 . That is, the processing circuit determines the rotational position of the PF motor 5 by counting the number of the respective edges E 1 and E 3 of the output signals S 1 and S 3 , or by counting the number of the respective edges E 2 and E 4 of the output signals S 2 and S 4 . Thus, in this embodiment, the predetermined processing circuit for determining the rotational position switches (selects) between determining the rotation position using the four output signals S and determining it using two output signals S according to the rotational speed of the PF motor 5 . The switching (selection) by the processing circuit is made according to the information on the rotational speed of the PF motor 5 determined from the output signals S of the rotary encoder 36 or the instruction from the CPU 39 based on the print mode information sent from the computer 50 or the like. The PF motor 5 is controlled on the basis of the information on the rotational position of the PF motor 5 determined from the four or two output signals S. For example, the PF motor 5 is PID-controlled on the basis of the rotational position of the PF motor 5 determined by the ASIC 51 . The rotating direction of the PF motor 5 is determined as follows: the rotating direction of the PF motor 5 is determined from the edges E of one output signal S and the output level of the other output signals S at that time. For example, as shown in FIG. 15 , if the output signals S 2 , S 3 , and S 4 are at low levels when the edge E 1 at the rising of the output signal S 1 is detected, it is determined that the PF motor 5 rotates in the normal direction. If the output signals S 2 , S 3 , and S 4 are at high levels when the edge E 1 at the rising of the output signal S 1 is detected, it is determined that the PF motor 5 rotates in the reverse direction. If the output signal S 1 is at a high level and the output signals S 3 and S 4 are at low levels when the edge E 2 at the rising of the output signal S 2 is detected, it is determined that the PF motor 5 rotates in the normal direction. On the other hand, if the output signal S 1 is at a low level and the output signals S 3 and S 4 are at high levels when the edge E 2 at the rising of the output signal S 2 is detected, it is determined that the PF motor 5 rotates in the reverse direction. Similarly, the rotating direction of the PF motor 5 is determined using the edges E 3 and E 4 of the output signals S 3 and S 4 and the output level of the other output signals S. Accordingly, if the above-described problems due to high-frequency signals such that the signals are output with two edges E overlapped with each other or the order of the edges E is reversed occur, a processing circuit of the controller 37 (for example, ASIC 51 ) cannot appropriately determine the rotating direction of the PF motor 5 . Accordingly, in this embodiment, like the detection of the rotational position, when the PF motor 5 rotates at a speed less than the predetermined rotation speed, or equal to or less than the predetermined rotational speed, and the problems due to the high-frequency signals do not occur, the processing circuit that detects the rotating direction detects the rotating direction using all the four output signals S and the four edges E. That is, the rotating direction of the PF motor 5 is detected by the output level of another output signal S when any one edge E among the edges E is detected. Further, when the PF motor 5 rotates at a speed that exceeds the predetermined rotational speed or is equal to or more than the predetermined rotational speed, and the problems due to the high-frequency signals occur, the predetermined processing of detecting the rotating direction detects the rotating direction of the PF motor 5 using two signals of the output signals S 1 and S 3 or two signals of the output signals S 2 and S 4 . That is, the rotating direction of the PF motor 5 is detected by the edges E 1 and E 3 of the output signals S 1 and S 3 , and the output level of another output signal S when one edge E is detected, or by the edges E 2 and E 4 of the output signals S 2 and S 4 , and the output level of another output signal S when one edge E is detected. Thus, in this embodiment, the processing circuit for determining the rotating direction switches (selects) between determining the rotating direction using four output signals S and determining the rotating direction using two output signals S, depending on the rotational speed of the PF motor 5 . The switching (selection) by the processing circuit is made according to the instruction from the CPU 39 based on the information on rotational speed of the PF motor 5 , as described above. Printer 1 is controlled on the basis of the information on the rotating direction of the PF motor determined using four or two output signals S. For example, the rotational position of the PF motor 5 is determined from the information on the rotating direction, and the PF motor 5 is PID-controlled on the basis of the determination. Next, the detection method of the rotation speed of the PF motor 5 will be described. The rotation speed of the PF motor 5 is detected using a time (cycle) from a rising edge (or falling edge) E of each output signal S to a next rising edge (or falling edge) E. For example, the rotation speed of the PF motor 5 is detected using the cycles T 1 , T 2 , T 3 , and T 4 shown in (E) to (H) of FIG. 14 . For this reason, even if two edges E are output to overlap each other or a sequence of the output edges E is reversed, a predetermined processing circuit (for example, the ASIC 51 ) of the control circuit 37 that detects the rotation speed can appropriately detect the rotation speed of the PF motor 5 . In this embodiment, the rotation speed of the PF motor 5 is detected using all the four output signals S, regardless of the rotation speed of the PF motor 5 . Further, a predetermined control of the printer 1 is performed on the basis of information about the rotation speed of the PF motor 5 detected using the four output signals S. For example, the PID control of the PF motor 5 is performed on the basis of information about the rotation speed of the PF motor 5 detected by the ASIC 51 . As described above, when the PF motor 5 rotates at the speed less than the predetermined rotation speed or equal to or less than the predetermined rotation speed, the ASIC 51 detects the rotation position of the PF motor 5 using the four output signals S. Meanwhile, when the PF motor 5 rotates that is equal to or more than the predetermined rotation speed or exceeds the predetermined rotation speed, the ASIC 51 detects the rotation speed of the PF motor 5 using the two output signals S. For this reason, as shown in FIG. 7 , when the rotation speed is equal to or more than the predetermined rotation speed V 1 , for example, only the target rotation speeds corresponding to the rotation positions detected from the output signals S 1 and S 3 are set in the target speed table. Further, if the rotation speed is less than the predetermined rotation speed V 1 , the target rotation speeds corresponding to the rotation positions detected from the output signals S 1 , S 2 , S 3 , and S 4 is set in the target speed table. With this configuration, the amount of data of the target speed table can be reduced. (Main Effects of First Embodiment) As described above, in the first embodiment, the rotary encoder 36 has the through holes 34 c that are provided to correspond to some of all the slits 65 for each predetermined interval. Therefore, a plurality of slits 65 can be formed, without worrying the wastes, such as the ink mist and so on, or the strength. In addition, the rotary encoder 36 outputs four output signals S from the level signals output from the light-receiving elements 69 arranged in four rows on one board 68 . The signals S are generated from the level signal waveforms of the four light-receiving elements A 1 ( 69 ) to A 4 ( 69 ), B 1 ( 69 ) to B 4 ( 69 ), C 1 ( 69 ) to C 4 ( 69 ), and D 1 ( 69 ) to D 4 ( 69 ) arranged at intervals corresponding to one quarter of the light and shade cycle T on the board 68 . Therefore, the output signals S have double the frequency of the level signals and the turning points of all the signals correspond to the turning points of the level signals of the light-receiving elements 69 . In other words, the cycles T 1 to T 4 of the signals S are a half of the cycle TL of the level signal waveform, and the edges E are generated in one-to-one correspondence with the light-receiving elements 69 . The rotary encoder 36 can therefore obtain such a resolution that slits are provided at intervals of one eighth of the interval of the slits 65 on the rotary scale 34 . In other words, the rotary encoder 36 can obtain a resolution of the position and speed eight times higher than that with the slits 65 . As a result, a rotary scale 34 of the same size and accuracy as conventional ones can provide a resolution of the position and speed eight times as high as the conventional ones. In other words, the rotary encoder 36 can output high-resolution output signals S. Also a rotary scale 34 smaller than conventional ones can provide a resolution of the position and speed equal to the conventional ones. In this embodiment, according to the rotation speed of the PF motor 5 , the control of the printer 1 on the basis of the two output signals of the output signal S 1 and the output signal S 3 or the two output signals of the output signal S 2 and the output signal S 4 , or the control of the printer 1 on the basis of the four output signals of the output signals S 1 , S 2 , S 3 , and S 4 is switchably (selectably) performed. For this reason, when the problems due to the high-frequency signals do not occur even through the control is performed using the four output signals S, the control of the printer 1 can be performed with higher resolution on the basis of the four output signals S. Further, in a case where the problems due to the high-frequency signals occur when the control is performed using the four output signals S, the control of the printer 1 can be performed using the two output signal S 1 and the output signal S 3 or the two output signals of the output signal S 2 and the output signal S 4 , whose phases are sifted from each other by an eighth of a brightness cycle T. For this reason, the problems due to the high-frequency signals can be suppressed, and the configuration of a circuit that processes the output signals from the rotary encoder 36 can be simplified. In this embodiment, when the rotation speed of the PF motor 5 is equal to or more than the predetermined speed, or exceeds the predetermined speed, the rotation position and the rotation direction of the PF motor 5 are detected from the two output signals of the output signal S 1 and the output signal S 3 or the two output signals of the output signal S 2 and the output signal output from the rotary encoder 36 , and the control is performed on the basis of the detection result. Further, when the rotation speed of the PF motor 5 is less than the predetermined speed, or is equal to or less than the predetermined speed, the rotation position and the rotation direction of the PF motor 5 are detected from the four output signals S output from the rotary encoder 36 . In case of the PF motor 5 , the positional accuracy of the PF motor 5 is demanded at the time of the stop, not at the time of the rotation. In this embodiment, before the PF motor 5 that rotates the rotation speed less than the predetermined speed or equal to or less than the predetermined speed stops, the rotation position or the rotation direction of the PF motor 5 can be detected from the four output signals S, and the control of the PF motor 5 can be performed on the basis of the detection result. Further, when the PF motor 5 rotates at a speed that is equal to or more than the predetermined speed or exceeds the predetermined speed, the rotation position or the rotation direction of the PF motor 5 is detected from the two output signals, and the control of the PF motor 5 is performed on the basis of the detection result. Even in this case, there is no problem in view of the positional accuracy. In this embodiment, the rotation speed of the PF motor 5 is detected from the four output signals S output from the rotary encoder 36 , regardless of the rotation speed of the PF motor 5 , and the control is performed on the basis of the detection result. For this reason, the accurate control of the PF motor 5 based on the more rotation speed information can be performed. Second Embodiment FIG. 16 is an electric circuit diagram of a rotary encoder 36 according to a second embodiment of the invention; and FIG. 17 shows signal waveforms generated by the rotary encoder 36 by the normal rotation of a rotary scale 34 according to the second embodiment, wherein (A) shows level signal waveforms amplified by a first amplifier 74 and a third amplifier 76 shown in FIG. 16 ; (B) shows a signal waveform output from a first-differential-signal generating circuit 78 shown in FIG. 16 ; (C) shows level signal waveforms amplified by a second amplifier 75 and a fourth amplifier 77 of FIG. 16 ; (D) shows a signal waveform output from a second-differential-signal generating circuit 79 of FIG. 16 ; (E) shows a signal waveform output from an exclusive OR circuit 80 shown in FIG. 16 ; (F) shows a signal waveform output from a row-B-signal generating circuit 71 shown in FIG. 16 ; (G) shows a signal waveform output from a row-C-signal generating circuit 72 shown in FIG. 16 ; (I) shows a signal waveform output from a row-D-signal generating circuit 73 shown in FIG. 16 ; (I) shows a signal waveform output from a first exclusive OR circuit 91 of FIG. 16 ; and (J) shows a signal waveform output from a second exclusive OR circuit 92 of FIG. 16 . Although the configurations of the rotary scale 34 of the rotary encoder 36 are identical, the first embodiment and the second embodiment are different in the structure of the electric circuit of the rotary encoder 36 . Because of the difference in the structure of the electric circuit, signals output from the rotary encoder 36 are also different. Since the other structures of the second embodiment are identical to those of the first embodiment, the difference will be principally described. In the second embodiment, components identical to those of the first embodiment are given the same reference numerals and descriptions thereof will be simplified or omitted. Illustrations and descriptions on components identical to those of the first embodiment will be omitted. Referring to FIG. 16 , the rotary encoder 36 of this embodiment includes the row-A-signal generating circuit 70 , the row-B-signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 which are described in the first embodiment. The row-A-signal generating circuit 70 , the row-B-signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 output the output signal S 1 , S 2 , S 3 , and S 4 shown in FIGS. 17(E) to 17(H) , respectively. In addition, the rotary encoder 36 of this embodiment includes a first output exclusive OR circuit 91 and a second output exclusive OR circuit 92 . The first output exclusive OR circuit 91 receives the signal S 1 output from the row-A-signal generating circuit 70 and the signal S 3 output from the row-C-signal generating circuit 72 . The first output exclusive OR circuit 91 generates a first output exclusive OR signal S 11 that is the exclusive OR of the output signal S 1 and the output signal S 3 , and outputs it. In other words, the first output exclusive OR circuit 91 generates and outputs the first output exclusive OR signal S 11 with a cycle approximately a half of the cycle of the output signals S 1 and S 3 , as shown in FIG. 17(I) . The second output exclusive OR circuit 92 receives the signal S 2 output from the row-B-signal generating circuit 71 and the signal S 4 output from the row-D-signal generating circuit 73 . The second output exclusive OR circuit 92 generates a second output exclusive OR signal S 12 that is the exclusive OR of the output signal S 2 and the output signal S 4 , and outputs it. In other words, the second output exclusive OR circuit 92 generates and outputs the second output exclusive OR signal S 12 with a cycle approximately a half of the cycle of the output signals S 2 and S 4 , as shown in FIG. 17(J) . The output signals S 1 and S 2 are out of phase with each other by one sixteenth of the light and shade cycle T. Accordingly, the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 are also out of phase with each other by one sixteenth of the light and shade cycle T, as shown in FIGS. 17(I) and 17(J) . The rotary encoder 36 of this embodiment also has four output terminals 81 , 82 , 83 , and 84 as in the first embodiment. Referring to FIG. 15 , the signal S 1 of the row-A-signal generating circuit 70 (the exclusive OR circuit 80 ) is output from the output terminal 81 , while the signal S 3 of the row-C-signal generating circuit 72 is output from the output terminal 82 . The first output exclusive OR signal S 11 output from the first output exclusive OR circuit 91 is output from the output terminal 83 , while the second output exclusive OR signal S 12 output from the second output exclusive OR circuit 92 is output from the output terminal 84 . In place of the output signal S 1 of the row-A-signal generating circuit 70 and the output signal S 3 of the row-C-signal generating circuit 72 , the signal S 2 of the row-B-signal generating circuit 71 and the signal S 4 of the row-D-signal generating circuit 73 may be output from the rotary encoder 36 . As in the first embodiment, the four output terminals 81 , 82 , 83 , and 84 connect to the controller 37 via the four signal lines 86 , 87 , 88 , and 89 , respectively (refer to FIG. 8 ). In this embodiment, the signals output from the rotary encoder 36 are different from those from the rotary encoder 36 of the first embodiment. Thus, a method for determining the rotational position and speed and the rotating direction of the PF motor 5 is different from that of the first embodiment. The method for determining the rotational position and speed and rotating direction of the PF motor 5 will be described in sequence. The method for determining the rotational position of the PF motor 5 will first be described. The rotational position of the PF motor 5 is determined by counting the number of the edges E 1 and E 3 of the output signals S 1 and S 3 shown in FIGS. 17(E) and 17(G) , respectively, or the edges E 11 and E 12 of the first output exclusive OR signal S 1 and the second output exclusive OR signal S 12 shown in FIGS. 17(I) and 17(J) , respectively. More specifically, in this embodiment, when the PF motor 5 rotates at the rotational speed less than the predetermined rotational speed or equal to or less than the predetermined rotational speed, and the problems due to the high-frequency signals do not occur, a predetermined processing circuit (for example, the ASIC 51 ) that detects the rotational position detects the rotational position of the PF motor 5 by counting the number of the edges E 11 and E 12 of the high-frequency first and second exclusive OR signals S 11 and S 12 . Further, when the PF motor 5 rotates at the rotational speed that is equal to or more than the predetermined rotational speed or exceeds the predetermined rotational speed, and the problems due to the high-frequency signals occur, the predetermined processing circuit that detects the rotational position detects the rotational position of the PF motor 5 by counting the number of the edges E 1 and E 3 of the low-frequency output signals S 1 and S 3 . Thus, in this embodiment, a predetermined processing circuit for determining the rotational position switches (selects) between determining the rotational position using the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 of high frequency and determining the rotational position using the output signals S 1 and S 3 of low frequency. The switching (selection) of the processing circuit is made according to instruction from the CPU 39 based on the information on the rotational speed of the PF motor 5 and so on, as in the first embodiment. The printer 1 is controlled on the basis of the information on the rotational position of the PF motor 5 determined from the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 or two output signals S 1 and S 3 . The PID control of the PF motor 5 is made on the basis of the information such as the rotational position of the PF motor 5 determined by the ASIC 51 . Next, the detection method of the rotation direction of the PF motor 5 will be described. The rotation direction of the PF motor 5 is detected from the edge E 1 of the output signal S 1 and/or the edge E 3 of the output signal S 3 , and the output level of the output signal S 3 and/or the output signal S 1 when the edge E 1 and/or the edge E 3 is detected. Alternatively, the rotation direction of the PF motor 5 is detected from the edge E 11 of the first exclusive OR signal S 11 and/or the edge E 12 of the second exclusive OR signal S 12 , and the output level of the second exclusive OR signal S 12 and/or the first exclusive OR signal S 1 when the edge E 11 and/or the edge E 12 is detected. The view for the detection of the rotation direction of the PF motor 5 is the same as the first embodiment, and the specified description thereof will be omitted. In this embodiment, like the detection of the rotation speed, when the PF motor 5 rotates at the rotation speed less than the predetermined rotation speed or equal to or less than the predetermined rotation speed, and the problems due to the high-frequency signals do not occur, a predetermined processing circuit (for example, the ASIC 51 ) that detects the rotation direction detects the rotation direction of the PF motor 5 using the high-frequency first and second exclusive OR signals S 11 and S 12 . Further, when the PF motor 5 rotates at the rotation speed that is equal to or more than the predetermined rotation speed or exceeds the predetermined rotation speed, and the problems due to the high-frequency problems occur, the predetermined processing circuit that detects the rotation direction detects the rotation direction of the PF motor 5 using the low-frequency output signals S 1 and S 3 . In such a manner, in this embodiment, according to the rotation speed of the PF motor 5 , the predetermined processing circuit that detects the rotation direction switches (selects) whether to detect the rotation position using the high-frequency first and second exclusive OR signals S 11 and S 12 or to detect the rotation position using the low-frequency output signals S 1 and S 3 . Switching (selection) at the predetermined processing circuit is performed, for example, by an instruction from the CPU 39 on the basis of the information about the rotation speed of the PF motor 5 . Further, a predetermined control of the printer 1 is performed on the basis of the information about the rotation position of the PF motor 5 detected using the first and second exclusive OR signals S 11 and S 12 or the two output signals S 1 and S 3 . For example, the rotation position of the PF motor 5 is detected on the basis of the information about the rotation direction, and the PID control of the printer 1 is performed on the basis of the detection result. A method for determining the rotational speed of the PF motor 5 will next be described. The rotational speed of the PF motor 5 can be determined using the time (period) from the edge E at which the output signals S 1 and S 3 (or the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 ) rise (or fall) to the edge E at the next rising (or falling). For example, the rotational speed of the PF motor 5 can be determined using times T 1 , T 3 , T 11 , and T 12 shown in FIGS. 17(E) , 17 (G), 17 (I), and 17 (J), respectively. Accordingly, the problems due to high-frequency signals, as described in the first embodiment, do not occur in determining the rotational speed. Thus, in this embodiment, the rotational speed of the PF motor 5 is determined using the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 of high frequency irrespective of the rotational speed of the PF motor 5 . Thus more rotational-speed information can be obtained from the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 . The printer 1 is controlled on the basis of the information on the rotational speed of the PF motor 5 determined using the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 . The PID control of the PF motor 5 made on the basis of the information such as the rotational speed of the PF motor 5 determined by the ASIC 51 . As described above, in the second embodiment, since the structure of the rotary scale 34 is the same as the first embodiment, a plurality of slits 65 can be formed, without worrying the wastes or the strength. In addition, the rotary encoder 36 generates four output signals S 1 , S 2 , S 3 , and S 4 from the level signals output from the light-receiving elements 69 arranged in four rows on one board 68 , of which it outputs two output signal S 1 and S 2 . In this embodiment, the rotary encoder 36 generates the first output exclusive OR signal S 11 having double the frequency of the output signals S 1 and S 3 from the output signals S 1 and S 3 and outputs it, and generates the second output exclusive OR signal S 12 having double the frequency of the output signals S 2 and S 4 from the output signals S 2 and S 4 and outputs it. The rotary encoder 36 can therefore obtain a resolution of position and speed eight times as high as with the slits 65 on the rotary scale 34 using the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 . As a result, the rotary scale 34 of the same size and accuracy as conventional ones can obtain a resolution of the position and speed eight times as high as the conventional ones. In other words, the rotary encoder 36 can output high-resolution output signals. Also a rotary scale 34 smaller than conventional ones can obtain a resolution of the position and speed equal to the conventional ones. In the second embodiment, according to the rotation speed of the PF motor 5 , the control of the printer 1 on the basis of the high-frequency first and second exclusive OR signals S 11 and S 12 or the control of the printer 1 on the basis of the low-frequency output signals S 1 and S 3 is switchably (selectably) performed. For this reason, when the problems due to the high-frequency signals do not occur even though the control is performed on the basis of the high-frequency first and second exclusive OR signals S 11 and S 12 , a predetermined control of the printer 1 can be performed with higher resolution on the basis of the first exclusive OR signal S 11 and the second exclusive OR signal S 12 . In addition, when the problems due to the high-frequency signals occur, the control of the printer 1 can be performed on the basis of the output signal S 1 and the output signal S 3 , whose phases are sifted from each other by an eighth of the brightness cycle T. For this reason, the problems due to the high-frequency signals can be suppressed, and the configuration of a circuit that processes the output signals from the rotary encoder 36 can be simplified. In the second embodiment, when the rotation speed of the PF motor 5 is equal to or more than the predetermined speed or exceeds the predetermined speed, the rotation position and the rotation direction of the PF motor 5 are detected from the high-frequency first and second exclusive OR signals S 11 and S 12 , and the control is performed on the basis of the detection result. Further, when the rotation speed of the PF motor 5 is less than the predetermined speed or is equal to or less then the predetermined speed, the rotation position and the rotation direction of the PF motor 5 are detected from the low-frequency output signals S 1 and S 3 , and the control is performed on the basis of the detection result. In case of the PF motor 5 , the positional accuracy of the PF motor 5 is demanded at the time of the stop, not at the time of the rotation. In this embodiment, before the PF motor 5 that rotates at the rotation speed less than the predetermined speed or equal to or less than the predetermined speed stops, the rotation position or the rotation direction of the PF motor 5 is detected from the high-frequency first and second exclusive OR signals S 11 and S 12 , and the control of the PF motor 5 can be performed on the basis of the detection result. Therefore, the positional accuracy of the PF motor 5 at the time of the stop can be increased. Further, when the PF motor 5 rotates at the rotation speed that is equal to or more than the predetermined speed or exceeds the predetermined speed, the rotation position or the rotation direction of the PF motor 5 is detected from the low-frequency output signals S 1 and S 3 , and the control of the PF motor 5 is performed on the basis of the detection result. Even in this case, there is no problem in view of the positional accuracy. Other Embodiments While preferred embodiments of the invention have been described, it is to be understood that the invention is not limited to those but various modifications and changes may be made without departing from the spirit and scope of the invention. In the above-described embodiments, the rotary encoder 36 includes the rotary scale 34 having the transparent main body portion 34 a formed of PET, the marks 34 b attached to one surface of the main body portion 34 a , and the through holes 34 c formed in some of the slits 65 . However, the main body portion 34 a may be formed of transparent resin or a glass substrate, in addition to PET. Further, the marks 34 b may be formed on both surfaces of the main body portion 34 a , not one surface thereof. Further, the marks 34 b are attached by deposition, such as sputtering or the like, or printing, but the marks 34 b may be provided by plating or exposure using a resist. In addition, in case of using a method of printing the marks 34 b , in addition to printing by an ink jet printer, other general printing methods can be used. Alternatively, the marks 34 b may be buried in the main body portion 34 a. The through holes 34 c may be provided at irregular intervals, not at regular intervals. For example, two through holes 34 c may be successively provided, and then another two through holes 34 c may be successively provided at an interval from the two through holes 34 c . Further, the through holes 34 c may be provided only in a predetermined angular range of the rotary scale 34 , not in other angular ranges. In addition, in the above-described embodiments, each of the through holes 34 c is a straight hole having the same width from the top to the bottom. However, each of the through holes 34 c may be formed such that a side close to the mark 34 b is wider and an opposing side is narrower or vice versa. In addition, the rotary encoder 36 includes the disc-shaped rotary scale 34 and the sensor 35 that senses the light passing through the slits 65 formed along the outer periphery thereof. Alternatively, the rotary encoder 36 may be of a reflection type that detects light reflected by a plurality of marks formed along the outer periphery of the rotary scale 34 . The structure of the invention may be applied to the linear encoder 33 that determines the rotational speed and position of the CR motor 4 . Specifically, the linear encoder 33 may be constructed such that a plurality of light-receiving elements is arranged on a board to which the light from light-emitting elements is reflected by the marks 31 a , as in FIG. 12 , and the level signals of the light-receiving elements are integrated together through the circuit shown in FIG. 13 or 16 . This arrangement enables the linear encoder 33 to output a plurality of signals with a resolution higher than that of the marks 31 a . The encoder may not necessarily be of an optical type but may be of magnetic or another type. In the foregoing embodiments, the rotary encoder 36 outputs one output signal from the level signals of, e.g., the four (=2 2 ) light-receiving elements A 1 ( 69 ) to A 4 ( 69 ). Alternatively, the rotary encoder 36 may generate one output signal from the level signals of 2n+1 (n is an integer of 1 or above) sets of light-receiving elements 69 , in which case the frequency of the output signal is 2n times that of the level signals of the light-receiving elements 69 . In this case, for example, the light-receiving elements 69 in row A and the light-receiving elements 69 in row C may be disposed on the board 68 with a displacement of one 2n+2th of the light and shade cycle T, and the light-receiving elements 69 in row B and the light-receiving elements 69 in row D may be disposed on the board 68 with a displacement of one 2n+2th of the light and shade cycle T. In the foregoing embodiments, the four light-receiving elements A 1 ( 69 ) to A 4 ( 69 ), B 1 ( 69 ) to B 4 ( 69 ), C 1 ( 69 ) to C 4 ( 69 ), and D 1 ( 69 ) to D 4 ( 69 ) are disposed next to each other in the range corresponding to the light and shade cycle T. However, they may not necessarily be disposed next to each other. For example, the first second light-receiving element A 2 ( 69 ), the third light-receiving element A 3 ( 69 ), and the fourth light-receiving element A 4 ( 69 ) in row A may be disposed in a position in which a distance integer times of the light and shade cycle T is added to the first position shown in FIG. 11 . The same arrangement is possible for rows B, C, and D. Furthermore, while rows A, B, C, and D are arranged with a displacement of one sixteenth of the light and shade cycle T with each other, they may be displaced at a pitch in which a distance integer times of the light and shade cycle T is added to one sixteenth of the light and shade cycle T. While the foregoing embodiments use the four light-receiving elements A 1 ( 69 ) to A 4 ( 69 ), B 1 ( 69 ) to B 4 ( 69 ), C 1 ( 69 ) to C 4 ( 69 ), and D 1 ( 69 ) to D 4 ( 69 ) to generate the signals S, for example, the output signal S 1 may be generated only with the first light-receiving element A 1 ( 69 ). Specifically, the output signal S 1 can be generated by generating a signal displaced from the signal detected by the first light-receiving element A 1 ( 69 ) by one half, one quarter, and three quarters, and inputting them to the amplifiers 74 , 75 , 76 , and 77 . The signals S 2 , S 3 , and S 4 can be generated similarly. In the foregoing embodiments, the output-signal generating circuits 70 , 71 , 72 , and 73 of four rows output signals that change at a duty of approximately 50%. Alternatively, the output-signal generating circuits 70 , 71 , 72 , and 73 may output at a duty other than 50%, in which case the four light-receiving elements A 1 ( 69 ) to A 4 ( 69 ) may be disposed at intervals with a displacement other than one quarter of the light and shade cycle T, or at intervals in which a displacement integer times of the light and shade cycle T is added to the displacement. In the first embodiment described above, according to the rotation speed of the PF motor 5 , the control of the printer 1 on the basis of the two output signals or the control of the printer 1 on the basis of the four output signals is switchably performed. Further, in the second embodiment, according to the rotation speed of the PF motor 5 , the control of the printer 1 on the basis of the high-frequency first exclusive OR circuit S 11 and so on or the control of the printer 1 on the basis of the low-frequency output signal S 1 and so on is switchably performed. Besides, according to the rotation position of the PF motor 5 , it may be configured on the basis of which signals to switchably perform the control of the printer 1 . For example, as shown in FIG. 6 , when the rotation position of the PF motor 5 is in a range of the target stop position X from a predetermined rotation position X 1 before the PF motor 5 stops (that is, in a range of a predetermined range from the target stop position X) or when the rotation position of the PF motor 5 is out of the range, it may be configured on the basis of which signals to switchably perform the control of the printer 1 . More specifically, when the rotation position of the PF motor 5 is in the predetermined range from the target stop position X of the PF motor 5 , the rotation position or the rotation direction of the PF motor 5 is detected from the four output signals S or from the high-frequency first and second exclusive OR signals S 11 and S 12 , and the control of the printer 1 is performed on the basis of the detection result. Further, when the rotation position of the PF motor 5 is out of the predetermined range from the target stop position X of the PF motor 5 , the rotation position or the rotation direction of the PF motor 5 is detected from the two output signals S, and the control of the printer 1 is performed on the basis of the detection result. With this configuration, the positional accuracy of the PF motor 5 at the time of the stop can be increased. Further, when the rotation position of the PF motor 5 is out of the predetermined range from the target stop position X of the PF motor 5 , a processing at the control unit 37 is simplified. In each of the embodiments described above, as for the detection of the rotation speed of the PF motor 5 , all the four output signals S or the high-frequency first and second exclusive OR signals S 11 and S 12 are used, regardless of the rotation speed of the PF motor 5 . Besides, according to the rotation speed of the PF motor 5 , the signals to be used for the detection of the rotation speed of the PF motor 5 may be switched. For example, when the PF motor 5 rotates at a speed less than a predetermined rotation speed or equal to or less than the predetermined rotation speed, the rotation speed of the PF motor 5 is detected using the four output signals S. Meanwhile, when the PF motor 5 rotates at a speed that is equal to or more than the predetermined rotation speed or exceeds the predetermined rotation speed, the rotation speed of the PF motor 5 may be detected using the two signals of the output signals S 1 and S 3 or the two signals of the output signals S 2 and S 4 . Further, when the PF motor 5 rotates at a speed less than the predetermined rotation speed or equal to or less than the predetermined rotation speed, the rotation speed of the PF motor 5 is detected using the high-frequency first and second exclusive OR signals S 11 and S 12 . Meanwhile, when the PF motor 5 rotates at a speed that is equal to or more than the predetermined rotation speed or exceeds the predetermined rotation speed, the rotation speed of the PF motor 5 may be detected using the low-frequency output signals S 1 and S 3 . In the above-described embodiments, the configuration of the invention has been described by way of the printer 1 . However, the encoder of the invention can be applied various fields, such as robots, machine tools, measurement, medical instruments, OA instruments, and so on. In addition, the arrangement of the invention can also be applied to multifunction printers, scanners, automatic document feeders (ADFs), copiers, facsimiles and so on.
A light emitter is operable to emit light. A scale comprises a transparent main body and a plurality of marks. The transparent main body has a first face and the second face which is opposite to the first face. The plurality of marks is provided on at least one of the first face and the second face and formed at a predetermined interval, and adapted to reflect or intercept the light emitted from the light emitter. A light detector is operable to detect light reflected by the marks or light passing through a plurality of regions each of which is defined between adjacent ones of the marks. The main body of the scale is formed with a plurality of through holes each of which connects the first face and the second face at one of the regions.
Briefly describe the main idea outlined in the provided context.
[ "BACKGROUND OF THE INVENTION The present invention relates to an encoder and a printer using the same.", "Printers have various motors such as a paper feed motor for driving a feed roller that conveys print paper or a print object and a carriage motor for driving a carriage having a print head.", "DC motors are widely used as such motors to reduce noise.", "Printers having DC motors are equipped with an encoder composed of a scale having marks or slits disposed at specified intervals and a sensor that senses the marks or slits of the scale to output given signals to control the positions and speeds of the DC motors.", "For example, to control a paper feed motor, printers have a disc-shaped scale having multiple slits arranged at specified intervals and a sensor constructed to sandwich each slit between a light-emitting device and a light-receiving device.", "This type of scale is constructed to rotate with a feed roller.", "This type of sensor generally outputs two signals with a phase difference of 90° (for example, refer to Japanese Patent Publication No. 2001-232882).", "The motor is controlled by sensing changing points of the levels of the two signals output from the sensor.", "Among the optical encoders, an optical encoder that has graduations attached to a transparent glass substrate, and allows light reflected by the graduations to pass through a space between the graduations is known (see Japanese Patent Publication No. 2001-232882).", "In order to improve print quality, more accurate control is required for motors mounted to printers.", "For more accurate control, encoders have to output signals with higher resolution.", "There may be two methods for outputting higher-resolution signals from encoders: a method of increasing the diameter of the disc-shaped scale while maintaining the intervals of the slits and a method of decreasing the interval of the slits while maintaining the diameter of the scale.", "However, printers that need to be compact cannot have a large-diameter scale.", "To provide the space for the scale, the mechanical structure of the printers becomes complicated.", "In contrast, narrowing the interval between slits makes it difficult to manufacture the scale itself.", "Since an ink mist occurs in an apparatus using ink, such as a printer, if the interval between the graduations is narrow, a portion, through which light passes, may significantly change due to the ink mist, and thus control may be made unstable.", "SUMMARY OF THE INVENTION Accordingly, it is an object of the invention to provide an encoder that, even though wastes, such as an ink mist and so on, are attached to a scale, can prevent output signals from being made unstable.", "It is another object of the invention to provide a printer that can perform stable control with high accuracy.", "In order to achieve the above objects, according to the embodiment of the invention, there is provided an encoder comprising: a light emitter, operable to emit light;", "a scale comprising: a transparent main body which has a first face and the second face which is opposite to the first face;", "and a plurality of marks provided on at least one of the first face and the second face and formed at a predetermined interval, and adapted to reflect or intercept the light emitted from the light emitter;", "and a light detector operable to detect light reflected by the marks or light passing through a plurality of regions each of which is defined between adjacent ones of the marks, wherein the main body of the scale is formed with a plurality of through holes each of which connects the first face and the second face at one of the regions.", "The number of the through hole may be no more than one third of a total number of the regions.", "The number of the through hole may be no less than one tenth of a total number of the regions.", "The marks may be arranged on the first face in a first direction;", "and a width in the first direction of the through hole may be wider than the interval between the marks.", "The marks may be arranged on the first face in a first direction;", "and a width in the first direction of the through hole may be narrower than the interval between the marks.", "According to the invention, there is also provided a printer operable to print information on a printing medium comprising: a motor having a rotatable shaft;", "the encoder described above, wherein the scale is rotated in conjunction with the rotation of the shaft, and the light detector is operable to output a signal in accordance with the rotation of the scale;", "a controller, which controls the rotation of the shaft based on the signal output from the detector.", "The motor may be operable to rotate a roller adapted to feed the printing medium.", "BRIEF DESCRIPTION OF THE DRAWINGS The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein: FIG. 1 is a schematic perspective view of a printer according to a first embodiment of the invention;", "FIG. 2 is a schematic side view of a part for paper feeding of the printer of FIG. 1 ;", "FIG. 3 is a schematic diagram of a carriage of FIG. 1 and a sensor mechanism of a PF drive roller of FIG. 2 ;", "FIG. 4 is a block diagram showing the schematic structure of a controller of the printer and its peripherals;", "FIG. 5 is a block diagram showing the structure of a speed control unit for a PF motor in a DC unit of FIG. 4 ;", "FIG. 6 is a graph of an example of target speed curves drawn from a target speed table;", "FIG. 7 is an enlarged view of part Z in FIG. 6 ;", "FIG. 8 is a schematic diagram of a part related to the rotary encoder in FIG. 3 ;", "FIG. 9 is a front view of the rotary scale in FIG. 3 ;", "FIG. 10 is a side view of the rotary encoder in FIG. 3 ;", "FIGS. 11A to 11C are partial cross-sectional views showing a structure of a rotary scale of FIG. 3 .", "FIG. 12 is a schematic diagram showing the relationship between the board in FIG. 10 and its peripherals;", "FIG. 13 is an electric circuit diagram of the rotary encoder of FIG. 3 ;", "FIG. 14 shows signal waveforms generated by the rotary encoder;", "FIG. 15 shows signal waveforms generated by the rotary encoder when the rotating direction is changed;", "FIG. 16 is an electric circuit diagram of a rotary encoder according to a second embodiment of the invention;", "FIG. 17 shows signal waveforms generated by the rotary encoder according to the second embodiment.", "DETAILED DESCRIPTION OF THE EMBODIMENTS Hereinafter, an encoder and a printer using the same according to an embodiment of the invention will be described in detail with reference to the accompanying drawings.", "Moreover, the configuration of the printer will first be described, and the configuration of the encoder will be described, together with the description of the printer.", "In addition, as regards the description of the printer, a control method of a printer will also be described.", "First Embodiment (Schematic Structure of Printer) FIG. 1 is a schematic perspective view of a printer 1 according to a first embodiment of the invention;", "FIG. 2 is a schematic side view of a part for paper feeding of the printer 1 of FIG. 1 ;", "FIG. 3 is a schematic diagram of a carriage 3 of FIG. 1 and a sensor mechanism of a PF drive roller 6 of FIG. 2 .", "The printer 1 of the first embodiment is an inkjet printer that ejects ink to print paper P or a print object to thereby execute printing.", "Referring to FIGS. 1 to 3 , the printer 1 includes a carriage 3 having a print head 2 that ejects ink droplets;", "a carriage motor (CR motor) 4 that drives the carriage 3 in a main scanning direction MS;", "a paper feed motor (PF motor) 5 that feeds the print paper P in a subscanning direction SS;", "a PF drive roller 6 connected to the PF motor 5 ;", "a platen 7 opposed to the nozzle surface (the lower surface in FIG. 2 ) of the print head 2 ;", "and a chassis 8 on which these components are mounted.", "In this embodiment, the CR motor 4 and the PF motor 5 are both a direct-current (DC) motor.", "As shown in FIG. 2 , the printer 1 further includes a hopper 11 on which the print paper P before printing is placed;", "a paper feed roller 12 and a separation pad 13 for taking the print paper P placed on the hopper 11 into the printer 1 ;", "a paper sensor 14 that senses the passage of the print paper P taken into the printer 1 from the hopper 11 ;", "and a delivery drive roller 15 that ejects the print paper P from the printer 1 .", "The carriage 3 can be moved in the main scanning direction MS by a guide shaft 17 supported by a support frame 16 fixed to the chassis 8 and a timing belt 18 .", "Specifically, the timing belt 18 runs between a pulley 19 and a pulley 20 under a specified tension, the pulley 19 being partly secured to the carriage 3 and being fixed to the output shaft of the CR motor 4 , and the pulley 20 being rotatably fixed to the support frame 16 .", "The guide shaft 17 sidably holds the carriage 3 so as to guide the carriage 3 in the main scanning direction MS.", "The carriage 3 further has an ink cartridge 21 in addition to the print head 2 , in which various inks to be supplied to the print head 2 are housed.", "The paper feed roller 12 connects to the PF motor 5 with a gear (not shown), and is driven by the PF motor 5 .", "As shown in FIG. 2 , the hopper 11 is a plate-like member on which the print paper P can be placed, which can be oscillated about a rotation shaft 22 at the top by a cam mechanism (not shown).", "The oscillation by the cam mechanism springily brings the lower end of the hopper 11 into and out of pressure contact with the paper feed roller 12 .", "The separation pad 13 is made of a high-friction member and is opposed to the paper feed roller 12 .", "As the paper feed roller 12 rotates, the surface of the paper feed roller 12 and the separation pad 13 come into pressure contact with each other.", "Accordingly, when the paper feed roller 12 rotates, the uppermost of the print paper P placed on the hopper 11 passes through the contact between the surface of the paper feed roller 12 and the separation pad 13 toward the delivery side;", "the second and later upper print paper P are stopped by the separation pad 13 .", "The PF drive roller 6 connects to the PF motor 5 directly or with a gear (not shown).", "As shown in FIG. 2 , the printer 1 further has a PF driven roller 23 that feeds the print paper P with the PF drive roller 6 .", "The PF driven roller 23 is rotatably held at the delivery side of a driven-roller holder 24 that is rotatable about a rotation shaft 25 .", "The driven-roller holder 24 is urged counterclockwise (in the drawing) by a spring (not shown) so that the PF driven roller 23 is constantly urged to the PF drive roller 6 .", "When the PF drive roller 6 is driven, the PF driven roller 23 also rotates with the PF drive roller 6 .", "As shown in FIG. 2 , the paper sensor 14 is composed of a sensing lever 26 and a sensor 27 , and is disposed in the vicinity of the driven-roller holder 24 .", "The sensing lever 26 is rotatable about a rotation shaft 28 .", "When the print paper P completes passing below the sensing lever 26 from the passing state shown in FIG. 2 , the sensing lever 26 turns counterclockwise.", "When the sensing lever 26 turns, the light from a light-emitting portion of the sensor 27 toward a light-receiving portion is interrupted to thereby sense the passage of the print paper P. The delivery drive roller 15 is disposed on the delivery side of the printer 1 , and connects to the PF motor 5 with a gear (not shown).", "As shown in FIG. 2 , the printer 1 further includes a delivery driven roller 29 for delivering the print paper P together with the delivery drive roller 15 .", "Like the PF driven roller 23 , the delivery driven roller 29 is also constantly urged toward the delivery drive roller 15 by a spring (not shown).", "When the delivery drive roller 15 is driven, the delivery driven roller 29 also rotates with the delivery drive roller 15 .", "Referring to FIG. 3 , the printer 1 further includes a linear encoder 33 having a linear scale 31 and a sensor 32 for determining the rotational position of the CR motor 4 (the position of the carriage 3 in the main scanning direction MS) and the rotational speed of the CR motor 4 (the speed of the carriage 3 );", "and a rotary encoder 36 having a rotary scale 34 and a sensor 35 for determining the rotational position of the PF motor 5 in the subscanning direction SS (the position of the print paper P in the subscanning direction SS) and the rotational speed of the PF motor 5 (the feeding speed of the print paper P).", "The linear scale 31 is shaped in a long straight line, and is mounted to the support frame 16 in parallel with the main scanning direction MS.", "The linear scale 31 has marks 31 a at specified intervals.", "The sensor 32 has a light-emitting device and a light-receiving device (not shown), and is mounted to the carriage 3 .", "The linear encoder 33 outputs a specified output signal in such a manner that the light emitted from the light-emitting device toward the linear scale 31 is reflected by the marks 31 a , and the light-receiving device receives the reflected light.", "Unlike a rotary scale 34 to be described below, the linear scale 31 does not have a main body portion formed of a transparent member.", "However, the linear scale 31 may have a main body portion formed of a transparent member.", "The rotary scale 34 is shaped like a disc, and is mounted to the PF drive roller 6 so as to rotate therewith.", "Specifically, when the PF drive roller 6 makes a turn, the rotary scale 34 also makes a turn.", "The sensor 35 is fixed to the chassis 8 with a bracket (not shown).", "Alternatively, the rotary scale 34 may be connected to the PF drive roller 6 with a gear or the like.", "However, mounting the rotary scale 34 directly to the PF drive roller 6 so as to rotate therewith allows one-to-one correspondence of the rotation amount of the rotary scale 34 and that of the PF drive roller 6 without errors such as play at the engaging portion of a gear.", "The details of the structure of the rotary encoder 36 will be described later.", "(Schematic Structure of Controller of Printer) FIG. 4 is a block diagram showing the schematic structure of a controller 37 of the printer 1 and its peripherals.", "As shown in FIG. 4 , the controller 37 includes a bus 38 , a CPU 39 , a ROM 40 , a RAM 41 , a character generator (CG) 42 , a nonvolatile memory 43 , an interface (I/F) dedicated circuit 44 , a DC unit 45 , a PF-motor drive circuit 46 , a CR-motor drive circuit 47 , a head drive circuit 48 , and an application-specific integrated circuit (ASIC) 51 .", "The controller 37 is configured such that the CPU 39 and the ASIC 51 receive output signals from the linear encoder 33 and the rotary encoder 36 .", "The CPU 39 performs operations for executing the control programs of the printer 1 stored in the ROM 40 and the nonvolatile memory 43 and other necessary operations.", "The ROM 40 stores control programs for controlling the printer 1 and data necessary for processing.", "For example, the ROM 40 stores a target speed table that contains target rotational speeds for the rotational positions of the CR motor 4 and the PF motor 5 .", "The RAM 41 temporarily stores programs that the CPU 39 is executing and data during operation.", "The CG 42 stores dot patterns expanded corresponding to print signals input to the I/F dedicated circuit 44 .", "The nonvolatile memory 43 stores various data that needs to be stored after the printer 1 is turned off.", "The I/F dedicated circuit 44 has a parallel interface circuit, which can receive print signals sent from a computer 50 via a connector 49 .", "The ASIC 51 controls the CR motor 4 and the PF motor 5 via the DC unit 45 , and controls the print head 2 via the head drive circuit 48 .", "The DC unit 45 is a control circuit for controlling the speed of the DC motor.", "The DC unit 45 performs various operations for controlling the speed of the CR motor 4 and the PF motor 5 according to the control instruction sent from the CPU 39 and signals output from the ASIC 51 via the I/F dedicated circuit 44 , and outputs motor control signals to the PF-motor drive circuit 46 and the CR-motor drive circuit 47 on the basis of the calculations.", "The PF-motor drive circuit 46 controls the driving of the PF motor 5 according to the motor control signal from the DC unit 45 .", "This embodiment adopts a pulse width modulation (PWM) control to control the PF motor 5 .", "Thus the PF-motor drive circuit 46 outputs a PWM driving signal.", "Similarly, the CR-motor drive circuit 47 controls the CR motor 4 in response to the motor control signal from the DC unit 45 .", "The head drive circuit 48 drives the nozzles of the print head 2 under the control instruction sent from the CPU 39 or the ASIC 51 via the I/F dedicated circuit 44 .", "The bus 38 is a signal line that connects the foregoing components of the controller 37 .", "The bus 38 interconnects the CPU 39 , the ROM 40 , the RAM 41 , the CG 42 , the nonvolatile memory 43 , and the I/F dedicated circuit 44 to enable exchange of data.", "(Structure of PF-Motor Speed Control Unit) FIG. 5 is a block diagram showing the structure of a speed control unit 53 for the PF motor 5 in the DC unit 45 ;", "FIG. 6 is a graph of examples of a target speed curve drawn from the target speed table stored in the ROM 40 of FIG. 4 ;", "and FIG. 7 is an enlarged view of part Z in FIG. 6 .", "As has been described, the DC unit 45 serves as a control circuit for controlling the speed of the CR motor 4 and the PF motor 5 .", "The structure of the speed control unit 53 for the PF motor 5 in the DC unit 45 will be described hereinbelow.", "A speed control unit for the CR motor 4 in the DC unit 45 has the same structure as the speed control unit 53 .", "As shown in FIG. 5 , the speed control unit 53 includes a location-deviation operating section 56 , a target-speed operating section 57 , a speed-deviation operating section 58 , a comparing element 59 , an integrator element 60 , a differentiating element 61 , an adding section 62 , and a D/A converter 63 .", "In other words, this embodiment employs a proportional, integral, and derivative (PID) control to control the PF motor 5 , in which the present rotational speed of the PF motor 5 is converged to a target rotational speed by a combination of comparing control, integral control, and derivative control.", "The location-deviation operating section 56 and the speed-deviation operating section 58 receive specified signals from the ASIC 51 .", "As has been described, the ASIC 51 receives a signal output from the rotary encoder 36 .", "The ASIC 51 outputs a present-rotational-position signal (a print-paper-P present-position signal) Pc corresponding to the present rotational position of the PF motor 5 responding to an output signal from the rotary encoder 36 , and a present-rotational-speed signal (a print-paper-P present-feed-speed signal) Vc corresponding to the present rotational speed of the PF motor 5 responding to an output signal from the rotary encoder 36 .", "The location-deviation operating section 56 receives the present-rotational-position signal Pc and a target-stop-position signal Pt corresponding to the next stop position of the print paper P in the subscanning direction SS.", "The location-deviation operating section 56 calculates and outputs a location-deviation signal dP corresponding to location deviation that is the difference between the input present-position signal Pc and the target-stop-position signal Pt.", "The target-stop-position signal Pt is input from the CPU 39 .", "The target-speed operating section 57 receives the location-deviation signal dP.", "The target-speed operating section 57 calculates and outputs a target-rotational-speed signal (a print-paper-P target-feed-speed signal) Vt corresponding to the target rotational speed of the PF motor 5 on the basis of the input location-deviation signal dP.", "More specifically, the target-speed operating section 57 reads a target-rotational-speed signal Vt corresponding to the location-deviation signal dP from the target speed table stored in the ROM 40 and outputs it.", "The solid line of FIG. 6 shows an example of a target speed curve created from the target speed table store in the ROM 40 .", "The target speed curve created from the target speed table has an accelerating region, a constant-speed region, and a decelerating region toward a target stop position X. The target speed table provides the target-rotational-speed signal Vt so as to correspond to the location-deviation signal dP in a specified range of values.", "Accordingly, the target speed curve is actually in the form of steps, as shown in FIG. 7 , so that the target rotational speed is held constant even if the location-deviation signal dP varies slightly.", "Rotational speed in the constant-speed region depends on print mode.", "For example, the ROM 40 also stores target-speed tables corresponding to the dotted line and the two-dot chain line in FIG. 6 .", "The ROM 40 also stores a target-speed table corresponding to various target stop positions.", "The speed-deviation operating section 58 receives the target-rotational-speed signal Vt and the present-rotational-speed signal Vc.", "The speed-deviation operating section 58 outputs a speed deviation signal dV that is the difference between the input target-rotational-speed signal Vt and the present-rotational-speed signal Vc.", "The speed deviation signal dV output from the speed-deviation operating section 58 is input to the comparing element 59 , the integrator element 60 , and the differentiating element 61 .", "The comparing element 59 , the integrator element 60 , and the differentiating element 61 respectively output a comparing-control-value signal QP, an integral-control-value signal QI, and a derivative-control-value signal QD calculated from the input speed deviation signal dV by a specified calculating expression.", "The adding section 62 receives the comparing-control-value signal QP output from the comparing element 59 , the integral-control-value signal QI output from the integrator element 60 , and the derivative-control-value signal QD output from the differentiating element 61 .", "The adding section 62 adds the control value signals QP, QI, and QD to output a PID-control-value signal □Q that is digital data, to the D/A converter 63 .", "The D/A converter 63 converts the digital PID-control-value signal □Q to analog data, and outputs it.", "The analog data output from the D/A converter 63 is input to the PF-motor drive circuit 46 as a motor control signal.", "(Structure of Rotary Encoder) FIG. 8 is a schematic diagram of a part related to the rotary encoder 36 of FIG. 3 ;", "FIG. 9 is a front view of the rotary scale 34 in FIG. 3 ;", "FIG. 10 is a side view of the sensor 35 in FIG. 3 ;", "FIGS. 11A to C are partial cross-sectional views showing a structure of the rotary scale of FIG. 3 ;", "FIG. 12 is a schematic diagram showing the relationship between a board 68 disposed to the sensor 35 shown in FIG. 10 and its peripherals.", "FIG. 13 is an electric circuit diagram of the rotary encoder 36 of FIG. 3 ;", "and FIG. 14 shows signal waveforms generated by the rotary encoder 36 by the normal rotation of the rotary scale 34 , wherein (A) shows level signal waveforms amplified by a first amplifier 74 and a third amplifier 76 shown in FIG. 13 ;", "(B) shows a signal waveform output from a first-differential-signal generating circuit 78 shown in FIG. 13 ;", "(C) shows level signal waveforms amplified by a second amplifier 75 and a fourth amplifier 77 shown in FIG. 13 ;", "(D) shows a signal waveform output from a second-differential-signal generating circuit 79 shown in FIG. 13 ;", "(E) shows a signal waveform output from an exclusive OR circuit 80 shown in FIG. 13 ;", "(F) shows a signal waveform output from a row-B-signal generating circuit 71 shown in FIG. 13 ;", "(G) is a signal waveform output from a row-C-signal generating circuit 72 shown in FIG. 13 ;", "and (H) is a signal waveform output from a row-D-signal generating circuit 73 shown in FIG. 13 .", "FIG. 15 shows signal waveforms generated by the rotary encoder 36 when the rotating direction of the rotary scale 34 is changed, wherein (A) shows a signal waveform output from the exclusive OR circuit 80 shown in FIG. 13 ;", "(B) shows a signal waveform output from the row-B-signal generating circuit 71 shown in FIG. 13 ;", "(C) shows a signal waveform output from the row-C-signal generating circuit 72 shown in FIG. 13 ;", "and (D) shows a signal waveform output from the row-D-signal generating circuit 73 shown in FIG. 13 .", "The rotary scale 34 is, for example, a plastic thin plate and is formed in a disc shape shown in FIG. 9 .", "As shown in FIG. 11A , the rotary scale 34 has a main body portion 34 a formed of polyethylene terephthalate (PET), and marks 34 b serving as graduations.", "The main body portion 34 a is transparent so as to allow light to pass therethrough.", "In this embodiment, the thickness of the main body portion 34 a is significantly thin, for example, 180 μm.", "Moreover, in FIGS. 11A to 11C , the marks 34 b are shown thick, but are actually set in a range of several μm to 20 μm.", "The marks 34 b are formed by attaching a non-transmissive material to a surface of the main body portion 34 a using printing or deposition.", "For this reason, light does not pass through the marks 34 b. In the rotary scale 34 , 180 slits 65 , each forming the space between the marks 34 b , are formed in a direction perpendicular to the paper of FIG. 9 .", "The 180 slits 65 are arranged at the same positions of the rotary scale 34 in a radial direction at regular angular intervals.", "That is, the 180 slits 65 are arranged at the regular angular intervals along an outer circumference of the rotary scale 34 .", "An interval between adjacent slits 65 and the width of each of the slits 65 in an arrangement direction of the slits 65 (a circumferential direction of the rotary scale 34 ) are substantially equal to each other.", "In FIG. 9 , for convenience, the slits 65 are displayed in the circumferential direction on a magnified scale, but the 180 slits 65 are actually formed in one round, and thus the width of each of the slits 65 in the circumferential direction is made significantly small.", "A through hole 34 c that has a width W 2 equal to the width W 1 of the slit 65 is formed to correspond to the slit 65 for every three slits 65 among the slits 65 .", "The through hole 34 c prevents the occurrence of diffused reflection or refraction due to a decrease in the amount of light passing through the slit 65 caused by the ink mist attached to the slit 65 .", "As shown in FIG. 11B , the rotary scale 34 may have the through hole 34 c that has a width W 3 larger than the width W 1 of the slit 65 .", "Further, as shown in FIG. 11B , the number of through holes 34 c to be provided may be a fourth of all the slits 65 , not a third of all the slits 65 (see FIG. 11A ).", "If the width W 3 of the through hole 34 c becomes larger than the width W 1 of the slit 65 , light 34 c passing through the periphery of the mark 34 b rarely enter the main body portion 34 a .", "If light 34 d enters the main body portion 34 a , light 34 d enters a deep part of the main body portion 34 a due to a refractive index when incident.", "Then, a light-receiving range of a light-receiving element 69 , which is described below, changes by the position of the light-receiving element 69 , and thus the output signals are rarely stabilized.", "The structure shown in FIG. 11B does not have such problems.", "The rotary scale 34 may have a structure shown in FIG. 11C .", "That is, the through hole 34 c may have a width W 4 smaller than the width W 1 of the slit 65 .", "With this configuration, the strength of the main body portion 34 a can be kept.", "Light passing through the periphery of a boundary portion 34 e between the mark 34 b and the slit 65 is incident on the main body portion 34 a from the top surface.", "Therefore, light that is received by the light-receiving element 69 can be stabilized, and a light-receivable region can be prevented from being expanded.", "Preferably, the through holes 34 c are respectively provided to correspond to slits 65 of a third to a tenth of all the slits 65 .", "If the through holes are respectively provided between marks of a tenth or more of all the marks, more wastes pass through the scale, and thus the wastes are rarely attached to the rotary scale 34 .", "Meanwhile, if the through holes 34 c are respectively provided between marks of a third or less of all the marks, the strength of the rotary scale 34 can be kept.", "Moreover, in view of strength balance, the through holes 34 c are preferably provided at predetermined regular intervals.", "The rotary scale 34 rotates with the PF drive roller 6 , as described above.", "That is, when the PF drive roller 6 makes a turn, the rotary scale 34 also makes a turn.", "When the peripheral length of the PF drive roller 6 is one inch, the resolution of the single rotary scale 34 is 180 (=1 in.", "/180) dpi.", "The rotary scale 34 may be connected to the PF drive roller 6 with a gear or the like, as described above, so that, e.g., the rotary scale 34 makes two turns when the PF drive roller 6 makes a turn.", "Referring to FIG. 10 , the sensor 35 has a substantially rectangular parallelepiped housing.", "The sensor 35 has a recess 66 from one side (the left side in FIG. 10 ) toward the center of the housing.", "A light-emitting element 67 or a light emitter is disposed on one of two opposing surfaces (two vertically opposing surfaces in FIG. 10 ) of the recess 66 , while a board 68 is disposed on the other surface.", "The board 68 has a plurality of light-receiving elements 69 or sensing elements (see FIG. 12 ), so that the portion of the board 68 serves as the photoreceiver (sensing portion) of the sensor 35 .", "The sensor 35 holds part of the outer periphery of the rotary scale 34 in the recess.", "Thus the outer periphery of the rotary scale 34 , that is, the portion of the rotary scale 34 where the slits 65 are formed is located between the light-emitting element 67 and the light-receiving elements 69 .", "The light-emitting element 67 is, for example, a light-emitting diode, which emits light having a good straight-forwarding performance.", "Referring to FIG. 12 , the board 68 has the light-receiving elements 69 arranged in four rows along the rotating direction of the rotary scale 34 .", "Hereinafter, the four rows of the light-receiving elements 69 are referred to as rows A, B, C, and D from the top of FIG. 12 .", "The light-receiving elements 69 are, for example, a photodiode, which output signals of a level according to the amount of received light.", "Moreover, in FIG. 12 , the main body portion 34 a formed of the transparent member is not shown.", "Assuming that the light-emitting element 67 emits parallel rays onto the board 68 , as shown in FIG. 12 , light and dark portions (light and shade) are formed on the surface of the board 68 at the same intervals as that of the slits 65 along the outer periphery of the rotary scale 34 .", "Specifically, the portions of the board 68 corresponding to the slits 65 are irradiated with the light from the light-emitting element 67 .", "The portions of the board 68 corresponding to the interval between the slits 65 of the rotary scale 34 are shielded from the light of the light-emitting element 67 .", "Thus, one cycle of the light and dark portions formed on the surface of the board 68 (hereinafter, referred to as a light and shade cycle T) corresponds to the arrangement pitch of the slits 65 of the rotary scale 34 .", "In other words, when the light-emitting element 67 irradiates the board 68 with parallel rays, the light and shade cycle T formed on the surface of the board 68 is the same as the pitch of the slits 65 .", "Accordingly, when the rotary scale 34 rotates at equal speed, the light and shade cycle T formed on the surface of the board 68 becomes substantially constant.", "When the light emitted from the light-emitting element 67 is not parallel rays, or is diffused light, the light and shade cycle T formed on the board 68 is narrow at the portion of the board 68 closest to the light-emitting element 67 , and is wider with an increasing distance from the light-emitting element 67 .", "Thus, in that case, even when the rotary scale 34 rotates at equal speed, the light and shade cycle T does not become constant.", "The light-receiving elements 69 in rows A to D are each disposed over a plurality of light and shade cycles T (three cycles in FIG. 12 ) of the board 68 .", "FIG. 12 shows the arrangement relationship among the light-receiving elements 69 in the case where the light from the light-emitting element 67 is parallel light.", "Each of the light-receiving elements 69 has a light-receiving surface of a size approximately one quarter of the light and shade cycle T formed on the board 68 .", "In other words, each of the light-receiving elements 69 in each row has a size equal to one quarter of the light and shade cycle T. As shown in FIG. 11 , a plurality of sets of four light-receiving elements 69 of a first light-receiving element A 1 ( 69 ) (B 1 ( 69 ), C 1 ( 69 ), or D 1 ( 69 ));", "a second light-receiving element A 2 ( 69 ) (B 2 ( 69 ), C 2 ( 69 ), or D 2 ( 69 ));", "a third light-receiving element A 3 ( 69 ) (B 3 ( 69 ), C 3 ( 69 ), or D 3 ( 69 ));", "a fourth light-receiving element A 4 ( 69 ) (B 4 ( 69 ), C 4 ( 69 ), or D 4 ( 69 )) corresponding to the light and shade cycle T is disposed in each of rows A to D from the left in the drawing.", "The light-receiving elements 69 in four rows are disposed with a slight displacement with each other in the rotating direction of the rotary scale 34 .", "More specifically, the four rows of light-receiving elements 69 are displaced one sixteenth of the light and shade cycle T with each other in the rotating direction of the rotary scale 34 .", "Referring to FIG. 12 , when the PF motor 5 rotates in the normal direction (in the direction in which the print paper P is fed to the delivery side) (when the rotary scale 34 rotates in the normal direction), the rotary scale 34 rotates from the left to the right of the drawing.", "In this case, row B is formed in a position shifted to the right of the light-receiving elements 69 in row A by one sixteenth of the light and shade cycle T. Row C is formed in a position shifted to the right of the light-receiving elements 69 in row A by two sixteenths of the light and shade cycle T. Row D is formed in a position shifted to the right of the light-receiving elements 69 in row A by three sixteenths of the light and shade cycle T. In other words, referring to FIG. 12 , for example, the light-receiving element A 1 ( 69 ) at the left end of row A, the light-receiving element B 1 ( 69 ) at the left end of row B, the light-receiving element C 1 ( 69 ) at the left end of row C, and the light-receiving element D 1 ( 69 ) at the left end of row D are displaced with each other in that order by one sixteenth of the light and shade cycle T (one cycle of light and shade) along the moving direction of the light and shade formed by the slits 65 .", "When the rotary scale 34 rotates with the PF drive roller 6 , the slits 65 move between the light-emitting element 67 and the light-receiving elements 69 of the sensor 35 .", "As the slits 65 moves, the light-receiving elements 69 output signals at a level depending on the amount of received light.", "More specifically, the light-receiving elements 69 corresponding to the slits 65 output high-level signals, while the light-receiving elements 69 corresponding to the interval between the slits 65 output low-level signals.", "Thus the light-receiving elements 69 output signal at a level varied in a cycle depending on the moving speed of the slits 65 .", "Referring to FIG. 13 , the sensor 35 that configures the rotary encoder 36 includes a row-A-signal generating circuit 70 or first signal generating means having a plurality of row-A light-receiving elements 69 , a row-B-signal generating circuit 71 or second signal generating means having a plurality of row-B light-receiving elements 69 , a row-C-signal generating circuit 72 or third signal generating means having a plurality of row-C light-receiving elements 69 , and a row-D-signal generating circuit 73 or fourth signal generating means having a plurality of row-D light-receiving elements 69 .", "The row-A-signal generating circuit 70 includes the row-A light-receiving elements 69 , the first to fourth amplifiers 74 , 75 , 76 , and 77 , the first differential-signal generating circuit 78 , the second differential-signal generating circuit 79 , and an exclusive OR circuit 89 .", "As shown in FIG. 12 , a plurality of sets of four light-receiving elements 69 , the first light-receiving element A 1 ( 69 ), the second light-receiving element A 2 ( 69 ), the third light-receiving element A 3 ( 69 ), and the fourth light-receiving element A 4 ( 69 ) corresponding to the light and shade cycle T is arranged in row A. The first amplifier 74 connects to the row-A first light-receiving elements A 1 ( 69 ) in parallel.", "The first light-receiving elements A 1 ( 69 ) each output a signal at a level responsive to their respective received light amount.", "The first amplifier 74 amplifies the level signals output from the first light-receiving elements A 1 ( 69 ).", "Similarly, the second amplifier 75 connects to the A-row second light-receiving elements A 2 ( 69 ) in parallel.", "The second amplifier 75 amplifies the level signals output from the second light-receiving elements A 2 ( 69 ), and outputs them.", "The third amplifier 76 connects to the row-A third light-receiving elements A 3 ( 69 ) in parallel.", "The third amplifier 76 amplifies the level signals output from the third light-receiving elements A 3 ( 69 ), and outputs them.", "The fourth amplifier 77 connects to the row-A fourth light-receiving elements A 4 ( 69 ) in parallel.", "The fourth amplifier 77 amplifies the level signals output from the fourth light-receiving elements A 4 ( 69 ), and outputs them.", "As shown in FIG. 12 , the first light-receiving elements A 1 ( 69 ) and the third light-receiving elements A 3 ( 69 ) are each formed on the board 68 in such a manner as to be displaced a half of the light and shade cycle T with respect to each other.", "Accordingly, as shown in FIG. 14(A) , the signal waveform amplified by the first amplifier 74 and the signal waveform amplified by the third amplifier 76 are displaced a half of the light and shade cycle T with respect to each other.", "Similarly, the second light-receiving elements A 2 ( 69 ) and the fourth light-receiving elements A 4 ( 69 ) are each formed on the board 68 in such a manner as to be displaced a half of the light and shade cycle T with respect to each other.", "Accordingly, as shown in FIG. 14(C) , the signal waveform amplified by the second amplifier 75 and the signal waveform amplified by the fourth amplifier 77 are displaced a half of the light and shade cycle T with respect to each other.", "The time of the cycle TL of the signal waveforms output from the amplifiers 74 , 75 , 76 , and 77 is the same as that of the light and shade cycle T. The first amplifier 74 and the third amplifier 76 output amplified level signals to the first-differential-signal generating circuit 78 .", "The level signal amplified by the first amplifier 74 is input to a noninverting input terminal of the first-differential-signal generating circuit 78 , while the level signal amplified by the first-differential-signal generating circuit 78 is input to an inverting input terminal of the first-differential-signal generating circuit 78 .", "When the level of the signal input to the noninverting input terminal (the signal output from the first amplifier 74 ) is higher than that of the signal input to the inverting input terminal (the signal output from the third amplifier 76 ), the first-differential-signal generating circuit 78 outputs a high-level signal;", "when the level of the signal input to the noninverting input terminal is lower than that of the signal input to the inverting input terminal, the first-differential-signal generating circuit 78 outputs a low-level signal.", "Thus the first-differential-signal generating circuit 78 outputs a digital-waveform signal.", "In other words, as shown in FIG. 14(B) , the first-differential-signal generating circuit 78 outputs a digital-waveform signal with a duty of approximately 50% substantially in the same cycle as that output from the third light-receiving element A 3 ( 69 ).", "The second amplifier 75 and the fourth amplifier 77 output amplified level signals to the second-differential-signal generating circuit 79 .", "The level signal amplified by the second amplifier 75 is input to a noninverting input terminal of the second-differential-signal generating circuit 79 , while the level signal amplified by the fourth amplifier 77 is input to an inverting input terminal of the second-differential-signal generating circuit 79 .", "When the level of the signal input to the noninverting input terminal (the signal output from the second amplifier 75 ) is higher than that of the signal input to the inverting input terminal (the signal output from the fourth amplifier 77 ), the second-differential-signal generating circuit 79 outputs a high-level signal;", "when the level of the signal input to the noninverting input terminal is lower than that input to the inverting input terminal, the second-differential-signal generating circuit 79 outputs a low-level signal.", "Thus the second-differential-signal generating circuit 79 outputs a digital-waveform signal.", "In other words, as shown in FIG. 14(D) , the second-differential-signal generating circuit 79 outputs a digital-waveform signal with a duty of approximately 50% substantially in the same cycle as that of the level signal output from the fourth light-receiving element A 4 ( 69 ).", "As shown in FIG. 12 , the first light-receiving elements A 1 ( 69 ) and the second light-receiving elements A 2 ( 69 ) are each formed on the board 68 in such a manner as to be displaced a quarter of the light and shade cycle T with respect to each other.", "Accordingly, the output signal of the first-differential-signal generating circuit 78 shown in FIG. 14(B) and the output signal of the second-differential-signal generating circuit 79 shown in FIG. 14 (D) are displaced a quarter of the light and shade cycle T with respect to each other.", "The output signal of the first-differential-signal generating circuit 78 and the output signal of the second-differential-signal generating circuit 79 are input to the exclusive OR circuit 80 .", "When both of the two inputs are on a high level or a low level, the exclusive OR circuit 80 outputs a low-level signal;", "when only one of the two inputs is on a high level, it outputs a high-level signal.", "Specifically, as shown in FIG. 14(E) , the exclusive OR circuit 80 outputs a signal S 1 with a cycle about a half of that of the level signal of the light-receiving elements 69 .", "When the rotating direction of the rotary scale 34 is changed at time t 0 , the exclusive OR circuit 80 outputs the signal S 1 shown in FIG. 15(A) .", "The output signal of the exclusive OR circuit 80 is output from an output terminal 81 of the rotary encoder 36 .", "The output signal of the exclusive OR circuit 80 (the output signal of the row-A-signal generating circuit 70 ) S 1 corresponds to a first output signal.", "Since the internal structures of the row-B-signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 are the same as that of the row-A-signal generating circuit 70 , drawings thereof and descriptions will be omitted.", "The row-B signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 respectively output signals S 2 , S 3 , and S 4 with a cycle approximately a half of the level signal of the light-receiving elements 69 shown in FIGS. 14(F) , 14 (G), and 14 (H).", "When the rotating direction of the rotary scale 34 is changed at time t 0 , the row-B-signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 respectively output signals S 2 , S 3 , and S 4 shown in FIGS. 15(B) , 15 (C), and 15 (D).", "As has been described, the light-receiving elements 69 in row B are displaced to the right of the light-receiving elements 69 in row A by a sixteenth of the light and shade cycle T. The light-receiving elements 69 in row C are displaced to the right of the light-receiving elements 69 in row A by two sixteenths of the light and shade cycle T. The light-receiving elements 69 in row D are displaced to the right of the light-receiving elements 69 in row A by three sixteenths of the light and shade cycle T. Therefore, as shown in FIGS. 14(E) to 14(H) , when the rotary scale 34 rotates in the normal direction, the phase of the output signal S 2 of the row-B-signal generating circuit 71 is basically delayed a sixteenth of the light and shade cycle T behind the phase of the output signal S 1 of the row-A-signal generating circuit 70 .", "The phase of the output signal S 3 of the row-C-signal generating circuit 72 is basically delayed two sixteenths of the light and shade cycle T behind the phase of the output signal S 1 of the row-A-signal generating circuit 70 .", "The phase of the output signal S 4 of the row-D-signal generating circuit 73 is basically delayed three sixteenths of the light and shade cycle T behind the phase of the output signal S 1 of the row-A-signal generating circuit 70 .", "As shown in FIG. 13 , the output signal S 2 of the row-B-signal generating circuit 71 is output from an output terminal 82 of the rotary encoder 36 ;", "the output signal S 3 of the row-C-signal generating circuit 72 is output from an output terminal 83 of the rotary encoder 36 ;", "and the output terminal S 4 of the row-D-signal generating circuit 73 is output from an output terminal 84 of the rotary encoder 36 .", "In other words, the rotary encoder 36 has four output terminals 81 , 82 , 83 , and 84 .", "The output signal S 2 of the row-B-signal generating circuit 71 corresponds to a second output signal;", "the output signal S 3 of the row-C-signal generating circuit 72 corresponds to a third output signal;", "and the output signal S 4 of the row-D-signal generating circuit 73 corresponds to a fourth output signal.", "Referring back to FIG. 8 , the four output terminals 81 , 82 , 83 , and 84 connect to the controller 37 with four signal lines 86 , 87 , 88 , and 89 , respectively.", "(Method for Controlling Printer) The printer 1 with this arrangement reciprocates the carriage 3 driven by the CR motor 4 in the main scanning direction MS while feeding the print paper P taken from the hopper 11 into the printer 1 with the paper feed roller 12 and the separation pad 13 in the subscanning direction SS with the PF drive roller 6 driven by the PF motor 5 .", "While the carriage 3 is reciprocating, the print head 2 jets out ink drops to print on the print paper P. Upon completion of printing to the print paper P, the print paper P is delivered to the outside of the printer 1 with the delivery drive roller 15 and so on.", "When the print paper P is fed in the subscanning direction SS, the PF motor 5 rotates the PF drive roller 6 .", "On rotation of the PF drive roller 6 , the rotary scale 34 rotates with the PF drive roller 6 .", "On rotation of the rotary scale 34 , the rotary encoder 36 outputs the four signals S 1 , S 2 , S 3 , and S 4 .", "The output signals S 1 , S 2 , S 3 , and S 4 are input to a predetermined processing circuit (e.g., the ASIC 51 ) of the controller 37 .", "To control the PF motor 5 and so on, the rotational position and speed of the PF motor 5 are determined from the output signals S 1 , S 2 , S 3 , and S 4 of the rotary encoder 36 .", "A method for determining the rotational position and speed and rotating direction of the PF motor 5 will be described in sequence.", "A method for determining the rotational position of the PF motor 5 will first be described.", "The rotational position of the PF motor 5 is determined using edges E 1 , E 2 , E 3 , and E 4 at which the levels of the output signals S 1 , S 2 , S 3 , and S 4 , shown in FIGS. 14(E) to 14(H) , change (rise and fall).", "In other words, the rotational position of the PF motor 5 is determined by counting the number of the edges E 1 , E 2 , E 3 , and E 4 output from the rotary encoder 36 .", "The four output signals S 1 , S 2 , S 3 , and S 4 are expressed as output signals S hereinbelow, if collectively expressed.", "The four edges E 1 , E 2 , E 3 , and E 4 are expressed as edges E, if collectively expressed.", "When the PF motor 5 rotates in both of the normal and reverse directions, the rotational position of the PF motor 5 is determined from the determination on the rotating direction, to be described later, and the number of the edges E. Here a case where the PF motor 5 rotates only in one direction will be described.", "For example, where the PF motor 5 rotates in the normal direction, the edges E are input when the edges E 1 , E 2 , E 3 , and E 4 are output from the rotary encoder 36 in that order, as shown in FIGS. 14(E) to 14(H) , so that the rotational position of the PF motor 5 can be determined appropriately by a predetermined processing circuit (e.g., the ASIC 51 ) of the controller 37 .", "The cycle of the output signals S is approximately a half of that of the level signal of the light-receiving elements 69 .", "The signals S 1 , S 2 , S 3 , and S 4 are basically sequentially output with a phase difference of one sixteenth of the light and shade cycle T. Accordingly, when the rotational speed of the PF motor 5 increases to output high-frequency signals S from the rotary encoder 36 , a phenomenon in which the edges E 1 , E 2 , E 3 , and E 4 are not output in that order, e.g., two edges E overlapped or the order of the output edges E are reversed, because of the characteristic of the electrical circuit of the rotary encoder 36 .", "To determine the rotational position of the PF motor 5 using the four output signals S under such a phenomenon due to the high-frequency signals, the structure of a processing circuit for determining the rotational position is complicated or the processing load on the processing circuit is increased.", "Accordingly, in this embodiment, when the PF motor 5 rotates at or below a specified rotational speed at which the foregoing problems due to high-frequency signals do not occur, a predetermined processing circuit determines the rotational position of the PF motor 5 using all the four output signals S. That is, the processing circuit determines the rotational position of the PF motor 5 by counting the number of the edges E of each of the four output signals S. On the other hand, when the PF motor 5 rotates at or over a specified rotational speed at which the foregoing problems due to high-frequency signals can occur, a predetermined processing circuit determines the rotational position of the PF motor 5 using the two output signals S 1 and D 3 or the two output signals S 2 and S 4 .", "That is, the processing circuit determines the rotational position of the PF motor 5 by counting the number of the respective edges E 1 and E 3 of the output signals S 1 and S 3 , or by counting the number of the respective edges E 2 and E 4 of the output signals S 2 and S 4 .", "Thus, in this embodiment, the predetermined processing circuit for determining the rotational position switches (selects) between determining the rotation position using the four output signals S and determining it using two output signals S according to the rotational speed of the PF motor 5 .", "The switching (selection) by the processing circuit is made according to the information on the rotational speed of the PF motor 5 determined from the output signals S of the rotary encoder 36 or the instruction from the CPU 39 based on the print mode information sent from the computer 50 or the like.", "The PF motor 5 is controlled on the basis of the information on the rotational position of the PF motor 5 determined from the four or two output signals S. For example, the PF motor 5 is PID-controlled on the basis of the rotational position of the PF motor 5 determined by the ASIC 51 .", "The rotating direction of the PF motor 5 is determined as follows: the rotating direction of the PF motor 5 is determined from the edges E of one output signal S and the output level of the other output signals S at that time.", "For example, as shown in FIG. 15 , if the output signals S 2 , S 3 , and S 4 are at low levels when the edge E 1 at the rising of the output signal S 1 is detected, it is determined that the PF motor 5 rotates in the normal direction.", "If the output signals S 2 , S 3 , and S 4 are at high levels when the edge E 1 at the rising of the output signal S 1 is detected, it is determined that the PF motor 5 rotates in the reverse direction.", "If the output signal S 1 is at a high level and the output signals S 3 and S 4 are at low levels when the edge E 2 at the rising of the output signal S 2 is detected, it is determined that the PF motor 5 rotates in the normal direction.", "On the other hand, if the output signal S 1 is at a low level and the output signals S 3 and S 4 are at high levels when the edge E 2 at the rising of the output signal S 2 is detected, it is determined that the PF motor 5 rotates in the reverse direction.", "Similarly, the rotating direction of the PF motor 5 is determined using the edges E 3 and E 4 of the output signals S 3 and S 4 and the output level of the other output signals S. Accordingly, if the above-described problems due to high-frequency signals such that the signals are output with two edges E overlapped with each other or the order of the edges E is reversed occur, a processing circuit of the controller 37 (for example, ASIC 51 ) cannot appropriately determine the rotating direction of the PF motor 5 .", "Accordingly, in this embodiment, like the detection of the rotational position, when the PF motor 5 rotates at a speed less than the predetermined rotation speed, or equal to or less than the predetermined rotational speed, and the problems due to the high-frequency signals do not occur, the processing circuit that detects the rotating direction detects the rotating direction using all the four output signals S and the four edges E. That is, the rotating direction of the PF motor 5 is detected by the output level of another output signal S when any one edge E among the edges E is detected.", "Further, when the PF motor 5 rotates at a speed that exceeds the predetermined rotational speed or is equal to or more than the predetermined rotational speed, and the problems due to the high-frequency signals occur, the predetermined processing of detecting the rotating direction detects the rotating direction of the PF motor 5 using two signals of the output signals S 1 and S 3 or two signals of the output signals S 2 and S 4 .", "That is, the rotating direction of the PF motor 5 is detected by the edges E 1 and E 3 of the output signals S 1 and S 3 , and the output level of another output signal S when one edge E is detected, or by the edges E 2 and E 4 of the output signals S 2 and S 4 , and the output level of another output signal S when one edge E is detected.", "Thus, in this embodiment, the processing circuit for determining the rotating direction switches (selects) between determining the rotating direction using four output signals S and determining the rotating direction using two output signals S, depending on the rotational speed of the PF motor 5 .", "The switching (selection) by the processing circuit is made according to the instruction from the CPU 39 based on the information on rotational speed of the PF motor 5 , as described above.", "Printer 1 is controlled on the basis of the information on the rotating direction of the PF motor determined using four or two output signals S. For example, the rotational position of the PF motor 5 is determined from the information on the rotating direction, and the PF motor 5 is PID-controlled on the basis of the determination.", "Next, the detection method of the rotation speed of the PF motor 5 will be described.", "The rotation speed of the PF motor 5 is detected using a time (cycle) from a rising edge (or falling edge) E of each output signal S to a next rising edge (or falling edge) E. For example, the rotation speed of the PF motor 5 is detected using the cycles T 1 , T 2 , T 3 , and T 4 shown in (E) to (H) of FIG. 14 .", "For this reason, even if two edges E are output to overlap each other or a sequence of the output edges E is reversed, a predetermined processing circuit (for example, the ASIC 51 ) of the control circuit 37 that detects the rotation speed can appropriately detect the rotation speed of the PF motor 5 .", "In this embodiment, the rotation speed of the PF motor 5 is detected using all the four output signals S, regardless of the rotation speed of the PF motor 5 .", "Further, a predetermined control of the printer 1 is performed on the basis of information about the rotation speed of the PF motor 5 detected using the four output signals S. For example, the PID control of the PF motor 5 is performed on the basis of information about the rotation speed of the PF motor 5 detected by the ASIC 51 .", "As described above, when the PF motor 5 rotates at the speed less than the predetermined rotation speed or equal to or less than the predetermined rotation speed, the ASIC 51 detects the rotation position of the PF motor 5 using the four output signals S. Meanwhile, when the PF motor 5 rotates that is equal to or more than the predetermined rotation speed or exceeds the predetermined rotation speed, the ASIC 51 detects the rotation speed of the PF motor 5 using the two output signals S. For this reason, as shown in FIG. 7 , when the rotation speed is equal to or more than the predetermined rotation speed V 1 , for example, only the target rotation speeds corresponding to the rotation positions detected from the output signals S 1 and S 3 are set in the target speed table.", "Further, if the rotation speed is less than the predetermined rotation speed V 1 , the target rotation speeds corresponding to the rotation positions detected from the output signals S 1 , S 2 , S 3 , and S 4 is set in the target speed table.", "With this configuration, the amount of data of the target speed table can be reduced.", "(Main Effects of First Embodiment) As described above, in the first embodiment, the rotary encoder 36 has the through holes 34 c that are provided to correspond to some of all the slits 65 for each predetermined interval.", "Therefore, a plurality of slits 65 can be formed, without worrying the wastes, such as the ink mist and so on, or the strength.", "In addition, the rotary encoder 36 outputs four output signals S from the level signals output from the light-receiving elements 69 arranged in four rows on one board 68 .", "The signals S are generated from the level signal waveforms of the four light-receiving elements A 1 ( 69 ) to A 4 ( 69 ), B 1 ( 69 ) to B 4 ( 69 ), C 1 ( 69 ) to C 4 ( 69 ), and D 1 ( 69 ) to D 4 ( 69 ) arranged at intervals corresponding to one quarter of the light and shade cycle T on the board 68 .", "Therefore, the output signals S have double the frequency of the level signals and the turning points of all the signals correspond to the turning points of the level signals of the light-receiving elements 69 .", "In other words, the cycles T 1 to T 4 of the signals S are a half of the cycle TL of the level signal waveform, and the edges E are generated in one-to-one correspondence with the light-receiving elements 69 .", "The rotary encoder 36 can therefore obtain such a resolution that slits are provided at intervals of one eighth of the interval of the slits 65 on the rotary scale 34 .", "In other words, the rotary encoder 36 can obtain a resolution of the position and speed eight times higher than that with the slits 65 .", "As a result, a rotary scale 34 of the same size and accuracy as conventional ones can provide a resolution of the position and speed eight times as high as the conventional ones.", "In other words, the rotary encoder 36 can output high-resolution output signals S. Also a rotary scale 34 smaller than conventional ones can provide a resolution of the position and speed equal to the conventional ones.", "In this embodiment, according to the rotation speed of the PF motor 5 , the control of the printer 1 on the basis of the two output signals of the output signal S 1 and the output signal S 3 or the two output signals of the output signal S 2 and the output signal S 4 , or the control of the printer 1 on the basis of the four output signals of the output signals S 1 , S 2 , S 3 , and S 4 is switchably (selectably) performed.", "For this reason, when the problems due to the high-frequency signals do not occur even through the control is performed using the four output signals S, the control of the printer 1 can be performed with higher resolution on the basis of the four output signals S. Further, in a case where the problems due to the high-frequency signals occur when the control is performed using the four output signals S, the control of the printer 1 can be performed using the two output signal S 1 and the output signal S 3 or the two output signals of the output signal S 2 and the output signal S 4 , whose phases are sifted from each other by an eighth of a brightness cycle T. For this reason, the problems due to the high-frequency signals can be suppressed, and the configuration of a circuit that processes the output signals from the rotary encoder 36 can be simplified.", "In this embodiment, when the rotation speed of the PF motor 5 is equal to or more than the predetermined speed, or exceeds the predetermined speed, the rotation position and the rotation direction of the PF motor 5 are detected from the two output signals of the output signal S 1 and the output signal S 3 or the two output signals of the output signal S 2 and the output signal output from the rotary encoder 36 , and the control is performed on the basis of the detection result.", "Further, when the rotation speed of the PF motor 5 is less than the predetermined speed, or is equal to or less than the predetermined speed, the rotation position and the rotation direction of the PF motor 5 are detected from the four output signals S output from the rotary encoder 36 .", "In case of the PF motor 5 , the positional accuracy of the PF motor 5 is demanded at the time of the stop, not at the time of the rotation.", "In this embodiment, before the PF motor 5 that rotates the rotation speed less than the predetermined speed or equal to or less than the predetermined speed stops, the rotation position or the rotation direction of the PF motor 5 can be detected from the four output signals S, and the control of the PF motor 5 can be performed on the basis of the detection result.", "Further, when the PF motor 5 rotates at a speed that is equal to or more than the predetermined speed or exceeds the predetermined speed, the rotation position or the rotation direction of the PF motor 5 is detected from the two output signals, and the control of the PF motor 5 is performed on the basis of the detection result.", "Even in this case, there is no problem in view of the positional accuracy.", "In this embodiment, the rotation speed of the PF motor 5 is detected from the four output signals S output from the rotary encoder 36 , regardless of the rotation speed of the PF motor 5 , and the control is performed on the basis of the detection result.", "For this reason, the accurate control of the PF motor 5 based on the more rotation speed information can be performed.", "Second Embodiment FIG. 16 is an electric circuit diagram of a rotary encoder 36 according to a second embodiment of the invention;", "and FIG. 17 shows signal waveforms generated by the rotary encoder 36 by the normal rotation of a rotary scale 34 according to the second embodiment, wherein (A) shows level signal waveforms amplified by a first amplifier 74 and a third amplifier 76 shown in FIG. 16 ;", "(B) shows a signal waveform output from a first-differential-signal generating circuit 78 shown in FIG. 16 ;", "(C) shows level signal waveforms amplified by a second amplifier 75 and a fourth amplifier 77 of FIG. 16 ;", "(D) shows a signal waveform output from a second-differential-signal generating circuit 79 of FIG. 16 ;", "(E) shows a signal waveform output from an exclusive OR circuit 80 shown in FIG. 16 ;", "(F) shows a signal waveform output from a row-B-signal generating circuit 71 shown in FIG. 16 ;", "(G) shows a signal waveform output from a row-C-signal generating circuit 72 shown in FIG. 16 ;", "(I) shows a signal waveform output from a row-D-signal generating circuit 73 shown in FIG. 16 ;", "(I) shows a signal waveform output from a first exclusive OR circuit 91 of FIG. 16 ;", "and (J) shows a signal waveform output from a second exclusive OR circuit 92 of FIG. 16 .", "Although the configurations of the rotary scale 34 of the rotary encoder 36 are identical, the first embodiment and the second embodiment are different in the structure of the electric circuit of the rotary encoder 36 .", "Because of the difference in the structure of the electric circuit, signals output from the rotary encoder 36 are also different.", "Since the other structures of the second embodiment are identical to those of the first embodiment, the difference will be principally described.", "In the second embodiment, components identical to those of the first embodiment are given the same reference numerals and descriptions thereof will be simplified or omitted.", "Illustrations and descriptions on components identical to those of the first embodiment will be omitted.", "Referring to FIG. 16 , the rotary encoder 36 of this embodiment includes the row-A-signal generating circuit 70 , the row-B-signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 which are described in the first embodiment.", "The row-A-signal generating circuit 70 , the row-B-signal generating circuit 71 , the row-C-signal generating circuit 72 , and the row-D-signal generating circuit 73 output the output signal S 1 , S 2 , S 3 , and S 4 shown in FIGS. 17(E) to 17(H) , respectively.", "In addition, the rotary encoder 36 of this embodiment includes a first output exclusive OR circuit 91 and a second output exclusive OR circuit 92 .", "The first output exclusive OR circuit 91 receives the signal S 1 output from the row-A-signal generating circuit 70 and the signal S 3 output from the row-C-signal generating circuit 72 .", "The first output exclusive OR circuit 91 generates a first output exclusive OR signal S 11 that is the exclusive OR of the output signal S 1 and the output signal S 3 , and outputs it.", "In other words, the first output exclusive OR circuit 91 generates and outputs the first output exclusive OR signal S 11 with a cycle approximately a half of the cycle of the output signals S 1 and S 3 , as shown in FIG. 17(I) .", "The second output exclusive OR circuit 92 receives the signal S 2 output from the row-B-signal generating circuit 71 and the signal S 4 output from the row-D-signal generating circuit 73 .", "The second output exclusive OR circuit 92 generates a second output exclusive OR signal S 12 that is the exclusive OR of the output signal S 2 and the output signal S 4 , and outputs it.", "In other words, the second output exclusive OR circuit 92 generates and outputs the second output exclusive OR signal S 12 with a cycle approximately a half of the cycle of the output signals S 2 and S 4 , as shown in FIG. 17(J) .", "The output signals S 1 and S 2 are out of phase with each other by one sixteenth of the light and shade cycle T. Accordingly, the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 are also out of phase with each other by one sixteenth of the light and shade cycle T, as shown in FIGS. 17(I) and 17(J) .", "The rotary encoder 36 of this embodiment also has four output terminals 81 , 82 , 83 , and 84 as in the first embodiment.", "Referring to FIG. 15 , the signal S 1 of the row-A-signal generating circuit 70 (the exclusive OR circuit 80 ) is output from the output terminal 81 , while the signal S 3 of the row-C-signal generating circuit 72 is output from the output terminal 82 .", "The first output exclusive OR signal S 11 output from the first output exclusive OR circuit 91 is output from the output terminal 83 , while the second output exclusive OR signal S 12 output from the second output exclusive OR circuit 92 is output from the output terminal 84 .", "In place of the output signal S 1 of the row-A-signal generating circuit 70 and the output signal S 3 of the row-C-signal generating circuit 72 , the signal S 2 of the row-B-signal generating circuit 71 and the signal S 4 of the row-D-signal generating circuit 73 may be output from the rotary encoder 36 .", "As in the first embodiment, the four output terminals 81 , 82 , 83 , and 84 connect to the controller 37 via the four signal lines 86 , 87 , 88 , and 89 , respectively (refer to FIG. 8 ).", "In this embodiment, the signals output from the rotary encoder 36 are different from those from the rotary encoder 36 of the first embodiment.", "Thus, a method for determining the rotational position and speed and the rotating direction of the PF motor 5 is different from that of the first embodiment.", "The method for determining the rotational position and speed and rotating direction of the PF motor 5 will be described in sequence.", "The method for determining the rotational position of the PF motor 5 will first be described.", "The rotational position of the PF motor 5 is determined by counting the number of the edges E 1 and E 3 of the output signals S 1 and S 3 shown in FIGS. 17(E) and 17(G) , respectively, or the edges E 11 and E 12 of the first output exclusive OR signal S 1 and the second output exclusive OR signal S 12 shown in FIGS. 17(I) and 17(J) , respectively.", "More specifically, in this embodiment, when the PF motor 5 rotates at the rotational speed less than the predetermined rotational speed or equal to or less than the predetermined rotational speed, and the problems due to the high-frequency signals do not occur, a predetermined processing circuit (for example, the ASIC 51 ) that detects the rotational position detects the rotational position of the PF motor 5 by counting the number of the edges E 11 and E 12 of the high-frequency first and second exclusive OR signals S 11 and S 12 .", "Further, when the PF motor 5 rotates at the rotational speed that is equal to or more than the predetermined rotational speed or exceeds the predetermined rotational speed, and the problems due to the high-frequency signals occur, the predetermined processing circuit that detects the rotational position detects the rotational position of the PF motor 5 by counting the number of the edges E 1 and E 3 of the low-frequency output signals S 1 and S 3 .", "Thus, in this embodiment, a predetermined processing circuit for determining the rotational position switches (selects) between determining the rotational position using the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 of high frequency and determining the rotational position using the output signals S 1 and S 3 of low frequency.", "The switching (selection) of the processing circuit is made according to instruction from the CPU 39 based on the information on the rotational speed of the PF motor 5 and so on, as in the first embodiment.", "The printer 1 is controlled on the basis of the information on the rotational position of the PF motor 5 determined from the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 or two output signals S 1 and S 3 .", "The PID control of the PF motor 5 is made on the basis of the information such as the rotational position of the PF motor 5 determined by the ASIC 51 .", "Next, the detection method of the rotation direction of the PF motor 5 will be described.", "The rotation direction of the PF motor 5 is detected from the edge E 1 of the output signal S 1 and/or the edge E 3 of the output signal S 3 , and the output level of the output signal S 3 and/or the output signal S 1 when the edge E 1 and/or the edge E 3 is detected.", "Alternatively, the rotation direction of the PF motor 5 is detected from the edge E 11 of the first exclusive OR signal S 11 and/or the edge E 12 of the second exclusive OR signal S 12 , and the output level of the second exclusive OR signal S 12 and/or the first exclusive OR signal S 1 when the edge E 11 and/or the edge E 12 is detected.", "The view for the detection of the rotation direction of the PF motor 5 is the same as the first embodiment, and the specified description thereof will be omitted.", "In this embodiment, like the detection of the rotation speed, when the PF motor 5 rotates at the rotation speed less than the predetermined rotation speed or equal to or less than the predetermined rotation speed, and the problems due to the high-frequency signals do not occur, a predetermined processing circuit (for example, the ASIC 51 ) that detects the rotation direction detects the rotation direction of the PF motor 5 using the high-frequency first and second exclusive OR signals S 11 and S 12 .", "Further, when the PF motor 5 rotates at the rotation speed that is equal to or more than the predetermined rotation speed or exceeds the predetermined rotation speed, and the problems due to the high-frequency problems occur, the predetermined processing circuit that detects the rotation direction detects the rotation direction of the PF motor 5 using the low-frequency output signals S 1 and S 3 .", "In such a manner, in this embodiment, according to the rotation speed of the PF motor 5 , the predetermined processing circuit that detects the rotation direction switches (selects) whether to detect the rotation position using the high-frequency first and second exclusive OR signals S 11 and S 12 or to detect the rotation position using the low-frequency output signals S 1 and S 3 .", "Switching (selection) at the predetermined processing circuit is performed, for example, by an instruction from the CPU 39 on the basis of the information about the rotation speed of the PF motor 5 .", "Further, a predetermined control of the printer 1 is performed on the basis of the information about the rotation position of the PF motor 5 detected using the first and second exclusive OR signals S 11 and S 12 or the two output signals S 1 and S 3 .", "For example, the rotation position of the PF motor 5 is detected on the basis of the information about the rotation direction, and the PID control of the printer 1 is performed on the basis of the detection result.", "A method for determining the rotational speed of the PF motor 5 will next be described.", "The rotational speed of the PF motor 5 can be determined using the time (period) from the edge E at which the output signals S 1 and S 3 (or the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 ) rise (or fall) to the edge E at the next rising (or falling).", "For example, the rotational speed of the PF motor 5 can be determined using times T 1 , T 3 , T 11 , and T 12 shown in FIGS. 17(E) , 17 (G), 17 (I), and 17 (J), respectively.", "Accordingly, the problems due to high-frequency signals, as described in the first embodiment, do not occur in determining the rotational speed.", "Thus, in this embodiment, the rotational speed of the PF motor 5 is determined using the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 of high frequency irrespective of the rotational speed of the PF motor 5 .", "Thus more rotational-speed information can be obtained from the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 .", "The printer 1 is controlled on the basis of the information on the rotational speed of the PF motor 5 determined using the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 .", "The PID control of the PF motor 5 made on the basis of the information such as the rotational speed of the PF motor 5 determined by the ASIC 51 .", "As described above, in the second embodiment, since the structure of the rotary scale 34 is the same as the first embodiment, a plurality of slits 65 can be formed, without worrying the wastes or the strength.", "In addition, the rotary encoder 36 generates four output signals S 1 , S 2 , S 3 , and S 4 from the level signals output from the light-receiving elements 69 arranged in four rows on one board 68 , of which it outputs two output signal S 1 and S 2 .", "In this embodiment, the rotary encoder 36 generates the first output exclusive OR signal S 11 having double the frequency of the output signals S 1 and S 3 from the output signals S 1 and S 3 and outputs it, and generates the second output exclusive OR signal S 12 having double the frequency of the output signals S 2 and S 4 from the output signals S 2 and S 4 and outputs it.", "The rotary encoder 36 can therefore obtain a resolution of position and speed eight times as high as with the slits 65 on the rotary scale 34 using the first output exclusive OR signal S 11 and the second output exclusive OR signal S 12 .", "As a result, the rotary scale 34 of the same size and accuracy as conventional ones can obtain a resolution of the position and speed eight times as high as the conventional ones.", "In other words, the rotary encoder 36 can output high-resolution output signals.", "Also a rotary scale 34 smaller than conventional ones can obtain a resolution of the position and speed equal to the conventional ones.", "In the second embodiment, according to the rotation speed of the PF motor 5 , the control of the printer 1 on the basis of the high-frequency first and second exclusive OR signals S 11 and S 12 or the control of the printer 1 on the basis of the low-frequency output signals S 1 and S 3 is switchably (selectably) performed.", "For this reason, when the problems due to the high-frequency signals do not occur even though the control is performed on the basis of the high-frequency first and second exclusive OR signals S 11 and S 12 , a predetermined control of the printer 1 can be performed with higher resolution on the basis of the first exclusive OR signal S 11 and the second exclusive OR signal S 12 .", "In addition, when the problems due to the high-frequency signals occur, the control of the printer 1 can be performed on the basis of the output signal S 1 and the output signal S 3 , whose phases are sifted from each other by an eighth of the brightness cycle T. For this reason, the problems due to the high-frequency signals can be suppressed, and the configuration of a circuit that processes the output signals from the rotary encoder 36 can be simplified.", "In the second embodiment, when the rotation speed of the PF motor 5 is equal to or more than the predetermined speed or exceeds the predetermined speed, the rotation position and the rotation direction of the PF motor 5 are detected from the high-frequency first and second exclusive OR signals S 11 and S 12 , and the control is performed on the basis of the detection result.", "Further, when the rotation speed of the PF motor 5 is less than the predetermined speed or is equal to or less then the predetermined speed, the rotation position and the rotation direction of the PF motor 5 are detected from the low-frequency output signals S 1 and S 3 , and the control is performed on the basis of the detection result.", "In case of the PF motor 5 , the positional accuracy of the PF motor 5 is demanded at the time of the stop, not at the time of the rotation.", "In this embodiment, before the PF motor 5 that rotates at the rotation speed less than the predetermined speed or equal to or less than the predetermined speed stops, the rotation position or the rotation direction of the PF motor 5 is detected from the high-frequency first and second exclusive OR signals S 11 and S 12 , and the control of the PF motor 5 can be performed on the basis of the detection result.", "Therefore, the positional accuracy of the PF motor 5 at the time of the stop can be increased.", "Further, when the PF motor 5 rotates at the rotation speed that is equal to or more than the predetermined speed or exceeds the predetermined speed, the rotation position or the rotation direction of the PF motor 5 is detected from the low-frequency output signals S 1 and S 3 , and the control of the PF motor 5 is performed on the basis of the detection result.", "Even in this case, there is no problem in view of the positional accuracy.", "Other Embodiments While preferred embodiments of the invention have been described, it is to be understood that the invention is not limited to those but various modifications and changes may be made without departing from the spirit and scope of the invention.", "In the above-described embodiments, the rotary encoder 36 includes the rotary scale 34 having the transparent main body portion 34 a formed of PET, the marks 34 b attached to one surface of the main body portion 34 a , and the through holes 34 c formed in some of the slits 65 .", "However, the main body portion 34 a may be formed of transparent resin or a glass substrate, in addition to PET.", "Further, the marks 34 b may be formed on both surfaces of the main body portion 34 a , not one surface thereof.", "Further, the marks 34 b are attached by deposition, such as sputtering or the like, or printing, but the marks 34 b may be provided by plating or exposure using a resist.", "In addition, in case of using a method of printing the marks 34 b , in addition to printing by an ink jet printer, other general printing methods can be used.", "Alternatively, the marks 34 b may be buried in the main body portion 34 a. The through holes 34 c may be provided at irregular intervals, not at regular intervals.", "For example, two through holes 34 c may be successively provided, and then another two through holes 34 c may be successively provided at an interval from the two through holes 34 c .", "Further, the through holes 34 c may be provided only in a predetermined angular range of the rotary scale 34 , not in other angular ranges.", "In addition, in the above-described embodiments, each of the through holes 34 c is a straight hole having the same width from the top to the bottom.", "However, each of the through holes 34 c may be formed such that a side close to the mark 34 b is wider and an opposing side is narrower or vice versa.", "In addition, the rotary encoder 36 includes the disc-shaped rotary scale 34 and the sensor 35 that senses the light passing through the slits 65 formed along the outer periphery thereof.", "Alternatively, the rotary encoder 36 may be of a reflection type that detects light reflected by a plurality of marks formed along the outer periphery of the rotary scale 34 .", "The structure of the invention may be applied to the linear encoder 33 that determines the rotational speed and position of the CR motor 4 .", "Specifically, the linear encoder 33 may be constructed such that a plurality of light-receiving elements is arranged on a board to which the light from light-emitting elements is reflected by the marks 31 a , as in FIG. 12 , and the level signals of the light-receiving elements are integrated together through the circuit shown in FIG. 13 or 16 .", "This arrangement enables the linear encoder 33 to output a plurality of signals with a resolution higher than that of the marks 31 a .", "The encoder may not necessarily be of an optical type but may be of magnetic or another type.", "In the foregoing embodiments, the rotary encoder 36 outputs one output signal from the level signals of, e.g., the four (=2 2 ) light-receiving elements A 1 ( 69 ) to A 4 ( 69 ).", "Alternatively, the rotary encoder 36 may generate one output signal from the level signals of 2n+1 (n is an integer of 1 or above) sets of light-receiving elements 69 , in which case the frequency of the output signal is 2n times that of the level signals of the light-receiving elements 69 .", "In this case, for example, the light-receiving elements 69 in row A and the light-receiving elements 69 in row C may be disposed on the board 68 with a displacement of one 2n+2th of the light and shade cycle T, and the light-receiving elements 69 in row B and the light-receiving elements 69 in row D may be disposed on the board 68 with a displacement of one 2n+2th of the light and shade cycle T. In the foregoing embodiments, the four light-receiving elements A 1 ( 69 ) to A 4 ( 69 ), B 1 ( 69 ) to B 4 ( 69 ), C 1 ( 69 ) to C 4 ( 69 ), and D 1 ( 69 ) to D 4 ( 69 ) are disposed next to each other in the range corresponding to the light and shade cycle T. However, they may not necessarily be disposed next to each other.", "For example, the first second light-receiving element A 2 ( 69 ), the third light-receiving element A 3 ( 69 ), and the fourth light-receiving element A 4 ( 69 ) in row A may be disposed in a position in which a distance integer times of the light and shade cycle T is added to the first position shown in FIG. 11 .", "The same arrangement is possible for rows B, C, and D. Furthermore, while rows A, B, C, and D are arranged with a displacement of one sixteenth of the light and shade cycle T with each other, they may be displaced at a pitch in which a distance integer times of the light and shade cycle T is added to one sixteenth of the light and shade cycle T. While the foregoing embodiments use the four light-receiving elements A 1 ( 69 ) to A 4 ( 69 ), B 1 ( 69 ) to B 4 ( 69 ), C 1 ( 69 ) to C 4 ( 69 ), and D 1 ( 69 ) to D 4 ( 69 ) to generate the signals S, for example, the output signal S 1 may be generated only with the first light-receiving element A 1 ( 69 ).", "Specifically, the output signal S 1 can be generated by generating a signal displaced from the signal detected by the first light-receiving element A 1 ( 69 ) by one half, one quarter, and three quarters, and inputting them to the amplifiers 74 , 75 , 76 , and 77 .", "The signals S 2 , S 3 , and S 4 can be generated similarly.", "In the foregoing embodiments, the output-signal generating circuits 70 , 71 , 72 , and 73 of four rows output signals that change at a duty of approximately 50%.", "Alternatively, the output-signal generating circuits 70 , 71 , 72 , and 73 may output at a duty other than 50%, in which case the four light-receiving elements A 1 ( 69 ) to A 4 ( 69 ) may be disposed at intervals with a displacement other than one quarter of the light and shade cycle T, or at intervals in which a displacement integer times of the light and shade cycle T is added to the displacement.", "In the first embodiment described above, according to the rotation speed of the PF motor 5 , the control of the printer 1 on the basis of the two output signals or the control of the printer 1 on the basis of the four output signals is switchably performed.", "Further, in the second embodiment, according to the rotation speed of the PF motor 5 , the control of the printer 1 on the basis of the high-frequency first exclusive OR circuit S 11 and so on or the control of the printer 1 on the basis of the low-frequency output signal S 1 and so on is switchably performed.", "Besides, according to the rotation position of the PF motor 5 , it may be configured on the basis of which signals to switchably perform the control of the printer 1 .", "For example, as shown in FIG. 6 , when the rotation position of the PF motor 5 is in a range of the target stop position X from a predetermined rotation position X 1 before the PF motor 5 stops (that is, in a range of a predetermined range from the target stop position X) or when the rotation position of the PF motor 5 is out of the range, it may be configured on the basis of which signals to switchably perform the control of the printer 1 .", "More specifically, when the rotation position of the PF motor 5 is in the predetermined range from the target stop position X of the PF motor 5 , the rotation position or the rotation direction of the PF motor 5 is detected from the four output signals S or from the high-frequency first and second exclusive OR signals S 11 and S 12 , and the control of the printer 1 is performed on the basis of the detection result.", "Further, when the rotation position of the PF motor 5 is out of the predetermined range from the target stop position X of the PF motor 5 , the rotation position or the rotation direction of the PF motor 5 is detected from the two output signals S, and the control of the printer 1 is performed on the basis of the detection result.", "With this configuration, the positional accuracy of the PF motor 5 at the time of the stop can be increased.", "Further, when the rotation position of the PF motor 5 is out of the predetermined range from the target stop position X of the PF motor 5 , a processing at the control unit 37 is simplified.", "In each of the embodiments described above, as for the detection of the rotation speed of the PF motor 5 , all the four output signals S or the high-frequency first and second exclusive OR signals S 11 and S 12 are used, regardless of the rotation speed of the PF motor 5 .", "Besides, according to the rotation speed of the PF motor 5 , the signals to be used for the detection of the rotation speed of the PF motor 5 may be switched.", "For example, when the PF motor 5 rotates at a speed less than a predetermined rotation speed or equal to or less than the predetermined rotation speed, the rotation speed of the PF motor 5 is detected using the four output signals S. Meanwhile, when the PF motor 5 rotates at a speed that is equal to or more than the predetermined rotation speed or exceeds the predetermined rotation speed, the rotation speed of the PF motor 5 may be detected using the two signals of the output signals S 1 and S 3 or the two signals of the output signals S 2 and S 4 .", "Further, when the PF motor 5 rotates at a speed less than the predetermined rotation speed or equal to or less than the predetermined rotation speed, the rotation speed of the PF motor 5 is detected using the high-frequency first and second exclusive OR signals S 11 and S 12 .", "Meanwhile, when the PF motor 5 rotates at a speed that is equal to or more than the predetermined rotation speed or exceeds the predetermined rotation speed, the rotation speed of the PF motor 5 may be detected using the low-frequency output signals S 1 and S 3 .", "In the above-described embodiments, the configuration of the invention has been described by way of the printer 1 .", "However, the encoder of the invention can be applied various fields, such as robots, machine tools, measurement, medical instruments, OA instruments, and so on.", "In addition, the arrangement of the invention can also be applied to multifunction printers, scanners, automatic document feeders (ADFs), copiers, facsimiles and so on." ]
This application is a Continuation-In-Part of application Ser. No. 10/238,241 Filed Sep. 10, 2002 now U.S. Pat. No. 6,937,341, and of Ser. No. 09/756,515 Filed Jan. 9, 2001 now U.S. Pat. No. 6,455,853, and therevia Claims benefit of Provisional Application Ser. No. 60/183,977 Filed Feb. 22, 2000. This Application is further a Continuation-In-Part of application Ser. No. 09/162,217, now U.S. Pat. No. 6,034,777, Filed Sep. 29, 1998 via Pending application Ser. Nos. 10/829,620, Filed Apr. 22, 2004, and 10/925,333 Filed Aug. 24, 2004, and 09/419,794, Filed Oct. 18, 1999 (now U.S. Pat. No. 6,549,282), which was a CIP of said 777 Patent. This Application directly Claims benefit from Provisional Applications 06/609,339, Filed Sep. 14, 2004; 60/598,456, Filed Aug. 3, 2004, and 60/530,416, Filed Dec. 17, 2003. TECHNICAL FIELD The disclosed invention relates to methodology for monitoring thin film deposition or removal from the surface of a substrate, and more particularly to methodology which combines Surface Plasmon Resonance (SPR) and Spectroscopic Ellipsometry (SE) techniques, involving use of process and/or wittness substrates with negative dielectric function e1, and small e2 in a specified wavelength range. Said method involves detection of changes in Ellipsometric Polarization State, (eg. DELTA or PSI), when P-polarized is caused to interact with a Sample at an Surface Plasmon inducing Resonant Angel-of-Incidence (AOI) to monitor deposition of and/or removal of minute amounts of materials onto, or from, a process and/or witness substrate, said monitoring being in combination with applying non-P Polarized electromagnetic radiation at the SPR resonance angle-of-incidence, and/or electromagnetic radiation of any polarization state at another angle-of-incidence, and conducting conventional ellipsometric analysis thereof simultaneously or sequentially. BACKGROUND Surface Plasmon Resonance (SPR) is a well-known optical diagnostics method used extensively by biologists to sensitively measure changes at surfaces. For insight it is noted that normally electromagnetic radiation reflects speculatly from smooth surfaces, or diffusely from rough surfaces, or reflects with combined specular and diffuse components. Surface Plasmon Resonance (SPR) refers to an unusual condition under which the light, rather than being immediately reflected, is absorbed and induces a surface “plasmon” or the like wave in the material. This occurs when using, for example, a gold film, and P-Polarized visible light (of say 650 nm wavelength) is caused to impinge upon thereupon at an SPR resonance angle of incidence of about 50 degrees to the normal to a surface thereof. This is described as a “resonant” condition for SPR. The P-Polarized light, (eg. which can comprise electromagnetic radiation of any functional wavelength), sets up a surface plasmon traveling wave along the surface of a metal. To date, SPR invariably uses either gold, silver, or other common metal for which plasmons are excited mainly by visible light. That is, the atomic nature of the material (metal) determines the resonant angle. In scientific terms, SPR can be performed on any material for which the real-part of the complex dielectric function (e1) is less than zero, in a wavelength region wherein imaginary part (e2) of the is complex dielectric function is not too great. Materials with negative real-part of dielectric function is useful wavelength ranges include especially low-mass materials, such as SiC, and Si-oxides. For example, SiC with real-part of dielectric constant. negative in spectral range 960 cm −1 to 780 cm −1 , and AIN has range 610 cm −I to 800 cm −1 negative dielectric function. SiO2 (quartz) is 1161 cm−1 to 1236 cm −1 . Hexagonal BN has useful ranges 1510 cm −1 to 1595 cm−1 and 1367 cm −1 to 1610 cm −1 , and cubic BN in range 1060 cm−1 to 1430 cm −1 . Graphite has possible resonance 867.8 cm−1 to 868.1 cm −1 ; narrow but potentially useful. Heavily doped binary, ternary, and quaternary alloys of compound 3/I semiconductors move the resonance into the useful 2 to 18 micron spectral range (555 cm −1 to 5000 cm −1 ) for biological materials (see attached review article table and graphs). Other examples might be intercalation compounds of graphite, which dope as both donors and acceptors. Metals have negative real-part of dielectric function negative at long-wavelengths, but are difficult to excite, but are possibly useful for these measurements, especially ultra-smooth metals such as Ir. Continuing, SPR can, sense both the time rate of change and the amount of attachment of biomaterial to a metal substrate. SPR is a known valuable method for development of new drug-release surfaces; development of sensors for toxins, bio-warfare threats, and diseases, development of new materials for implants in humans (such as stints and heart valves), and for numerous other biomedical and bioengineering applications. SPR is hundreds of times more sensitive than conventional spectroscopies for thin films. One example, (of hundreds), is in the monitoring of the attachment of toxins, (such as cholera), to surfaces functionallized by IgG protein. To date most applications have been in bio-material monitoring. While the herein disclosed invention can be used in any material system investigation system such as Polarimeter, Reflectomerter, Spectrophotometer and the like Systems, an important application is with Ellipsometer Systems, whether monochromatic or spectroscopic. It should therefore be understood that Ellipsometry involves acquisition of sample system characterizing data at single or multiple Wavelengths, and at one or more Angle(s)-of-Incidence (AOI) of a Beam of Electromagnetic Radiation to a surface of the sample system. Ellipsometry is generally well described in a great many publication, one such publication being a review paper by Collins, titled “Automatic Rotating Element Ellipsometers: Calibration, Operation and Real-Time Applications”, Rev. Sci. Instrum., 61(8) (1990). A typical goal in ellipsometry is to obtain, for each wavelength in, and angle of incidence of said beam of electromagnetic radiation caused to interact with a sample system, sample system characterizing PSI and DELTA values, where PSI is related to a change in a ratio of magnitudes of orthogonal components r p /r s in said beam of electromagnetic radiation, and wherein DELTA is related to a phase shift entered between said orthogonal components r p and r s , caused by interaction with said sample system. This is expressed by: TAN(ψ) e i(Δ) =r s /r p . (Note the availability of the phase DELTA (Δ) data is a distinguishing factor between ellipsometry and reflectometry). Ellipsometer Systems generally include a source of a beam of electromagnetic radiation, a Polarizer, which serves to impose a state of polarization on a beam of electromagnetic radiation, a Stage for supporting a sample system, and an Analyzer which serves to select a polarization state in a beam of electromagnetic radiation after it has interacted with a material system, and passed it to a Detector System for analysis therein. As well, one or more Compensator(s) can be present and serve to affect a phase angle between orthogonal components of a polarized beam of electromagnetic radiation. A number of types of ellipsometer systems exist, such as those which include rotating elements and those which include modulation elements. Those including rotating elements include Rotating Polarizer (RP), Rotating Analyzer (RA) and Rotating Compensator (RC). A preferred embodiment is a Rotating Compensator Ellipsometer System because, it is noted, Rotating Compensator Ellipsometer Systems do not demonstrate “Dead-Spots” where obtaining data is difficult. They can read PSI and DELTA of a Material System over a full Range of Degrees with the only limitation being that if PSI becomes essentially zero (0.0), DELTA can not then be determined as there is not sufficient PSI Polar Vector Length to form the angle between the PSI Vector and an “X” axis. In comparison, Rotating Analyzer and Rotating Plarizer Ellipsometers have “Dead Spots” at DELTA's near 0.0 or 180 Degrees and Modulation Element Ellipsometers also have “Dead Spots” at PSI near 45 Degrees). The utility of Rotating Compensator Ellipsometer Systems should then be apparent. Another benefit provided by fixed Polarizer (P) and Analyzer (A) positions is that polarization state sensitivity to input and output optics during data acquisition is essentially non-existent. This enables relatively easy use of optic fibers, mirrors, lenses etc. for input/output. Further, it is to be understood that causing a polarized beam of electromagnetic radiation to interact with a sample system generally causes change in the ratio of the intensities of orthogonal components thereof and/or the phase angle between said orthogonal components. The same is generally true for interaction between any system component and a polarized beam of electromagnetic radiation. In recognition of the need to isolate the effects of an investigated sample system from those caused by interaction between a beam of electromagnetic radiation and system components other than said sample system, (to enable accurate characterization of a sample system per se.), this Specification incorporates by reference the regression procedure of U.S. Pat. No. 5,872,630 to Johs et al. in that it describes simultaneous evaluation of sample characterizing parameters such as PSI and DELTA, as well system characterizing parameters, and this Specification also incorporates by reference the Vacuum Chamber Window Correction methodology of U.S. Pat. No. 6,034,777 to Johs et al. to account for phase shifts entered between orthogonal components of a beam of electromagnetic radiation, by disclosed invention system windows and/or beam entry elements. For insight, one embodiment of said method of accurately evaluating parameters in parameterized equations in a mathematical model of a system of spatially separated input and output windows, said parameterized equations enabling, when parameters therein are properly evaluated, independent calculation of retardation entered by each of said input window and said output window between orthogonal components of a beam of electromagnetic radiation caused to pass through said input and output windows, at least one of said input and output windows being birefringent, said method comprises, in a functional order, the steps of: a. providing spatially separated input and output windows, at least one of said input and output windows demonstrating birefringence when a beam of electromagnetic radiation is caused to pass therethrough, there being a means for supporting a sample system positioned between said input and output windows; b. positioning an ellipsometer system source of electromagnetic radiation and an ellipsometer system detector system such that in use a beam of electromagnetic radiation provided by said source of electromagnetic radiation is caused to pass through said input window, interact with said sample system in a plane of incidence thereto, and exit through said output window and enter said detector system; c. providing a sample system to said means for supporting a sample system, the composition of said sample system being sufficiently well known so that retardence entered thereby to a polarized beam of electromagnetic radiation of a given wavelength, which is caused to interact with said sample system in a plane of incidence thereto, can be accurately modeled mathematically by a parameterized equation which, when parameters therein are properly evaluated, allows calculation of retardence entered thereby between orthogonal components of a beam of electromagnetic radiation caused to interact therewith in a plane of incidence thereto, given wavelength; d. providing a mathematical model for said ellipsometer system and said input and output windows and said sample system, comprising separate parameterized equations for independently calculating retardence entered between orthogonal components of a beam of electromagnetic radiation caused to pass through each of said input and output windows and interact with said sample system in a plane of incidence thereto; such that where parameters in said mathematical model are properly evaluated, retardence entered between orthogonal components of a beam of electromagnetic which passes through each of said input and output windows and interacts with said sample system in a plane of incidence thereto can be independently calculated from said parameterized equations, given wavelength; e. obtaining a spectroscopic set of ellipsometric data with said parameterizable sample system present on the means for supporting a sample system, utilizing a beam of electromagnetic radiation provided by said source of electromagnetic radiation, said beam of electromagnetic radiation being caused to pass through said input window, interact with said parameterizable sample system in a plane of incidence thereto, and exit through said output window and enter said detector system; f. by utilizing said mathematical model provided in step d. and said spectroscopic set of ellipsometric data obtained in step e., simultaneously evaluating parameters in said mathematical model parameterized equations for independently calculating retardence entered between orthogonal components in a beam of electromagnetic radiation caused to pass through said input window, interact with said sample system in a plane of incidence thereto, and exit through said output window; to the end that application of said parameterized equations for each of said input window, output window and sample system for which values of parameters therein have been determined in step f., enables independent calculation of retardence entered between orthogonal components of a beam of electromagnetic radiation by each of said input and output windows, and said sample system, at given wavelengths in said spectroscopic set of ellipsometric data, said calculated retardence values for each of said input window, output window and sample system being essentially uncorrelated. No known references teach combined use of Surface Plasmon Resonance data which is obtained using P-Polarized electromagnetic radiation directed to a substrate surface at a Resonance angle-of-incidence, and conventional ellipsometric data which is obtained using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said Resonance angle-of-incidence, in monitoring and optionally controlling thin film deposition or removal from the surface of said substrate. DISCLOSURE OF THE INVENTION The present invention recognizes that while Ellipsometry provides sensitivity to layers of material on the order of a nonometer, additional sensitivity to even thinner layers would be of benefit. The present invention provides for the use of the Surface Plasmon Resonance (SPR) effect in the monitoring of deposition or etching of thin layers of material, either independently or in symbiotic combination with practice of conventional ellipsometry. It is noted that the SPR technique requires that P-Polarized electromagnetic radiation be applied, whereas conventional ellipsometry can utilize any polarization orientation. The present invention then provides for application of P-Polarized and Non-P-Polarized electromagnetic radiation, simultaneously or sequentially, to a sample during deposition or removal of one or more thin films on a surface thereof. A primary embodiment of the method of monitoring the deposition or removal of material from the surface of a substrate comprising the steps of: a) while material is being deposited or removed from said substrate surface, by causing electromagnetic radiation to impinge on, interact with and then enter a detector: obtaining ellipsometric data using P-Polarized electromagnetic radiation directed to a substrate surface at a Surface Plasmon Resonance Resonance angle-of-incidence to said sample surface, and simultaneously or sequentially obtaining conventional ellipsometric data using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said SPR Resonance angle-of-incidence; b) analyzing said data to arrive at a thickness for deposited or removed material. Said method can further comprise the step of controlling deposition or removal of material using said ellipsometric data. Said method can involve said ellipsometric data obtained using P-Polarized electromagnetic radiation at the SPR resonance angle-of-incidence and data, and said ellipsometric data simultaneously or sequentially obtaining using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said SPR Resonance angle-of-incidence, being analyzed simultaneously. Another embodiment of the present invention is a method of monitoring deposition of, or etching of material from a sample surface comprising the steps of: a) providing an ellipsometer system comprising a source of electromagnetic radiation, a polarizer, a sample supporting stage, an analyzer and a detector and means for changing the angle-of-incidence at which the beam approaches said sample surface; a) placing a sample onto said sample supporting stage and by adjusting said polarizer, providing incident P-Polarized electromagnetic radiation to said sample surface, and while monitoring P-Polarized electromagnetic radiation reflected from said sample surface adjusting the angle-of-incidence until surface plasmon resonance occurs as evidenced by a large change in intensity or a determined ellipsometric PSI and/or DELTA, thereby indicating that the surface plasmon resonance angle-of-incidence has been identified; b) while depositing material onto or etching material from said sample surface, monitoring change in the ellipsometric PSI and/or DELTA which results from the P-Polarized electromagnetic radiation; c) said method further comprising providing incident non-P-Polarized electromagnetic radiation at the SPR Resonance, or another angle-of-incidence onto said sample surface such that it reflects into the same, or another detector, and determining a conventional ellipsometric PSI and/or DELTA therefrom; such that changes in said ellipsometric PSI's and/or DELTA's resulting from the P-Polarized and from the non-P-Polarized beams indicate deposition of, or etching of material from said sample surface. It is noted that the P-Polarized and non-P-Polarized electromagnetic radiation can be simultaneously or sequentially applied to said sample surface, at the same, or at different angles-of-incidence. Also, where bio-materials are involved, the P-Polarized and non-P-Polarized electromagnetic radiation can comprise infrared wavelengths. Still another embodiment of the presently disclosed invention is a method of controlling deposition or etching of thin layers of material to or from substrates comprising the steps of: a) providing a system for deposition of materials onto a process substrate placed therewithin, including a system for providing a beam of P-polarized electromagnetism and orienting it to direct said beam at an oblique angle of incidence to a surface of said process substrate, and/or a wittness substrate, reflect therefrom and enter a detector for monitoring ellipsometric PSI and DELTA of said process substrate and/or wittness substrate, said process substrate or wittness substrate having a negative e1 at at least one wavelength; b) adjusting the angle of incidence of the electromagnetic beam to a surface of said process substrate and/or wittness substrate until a decrease of intensity is noted at the detector for said at least one wavelength at which the e1 is negative, indicating formation of a surface plasmon in said process substrate and/or wittness substrate; c) while monitoring at least the ellipsometric DELTA of said process substrate and/or wittness substrate at said at least one wavelength at which its e1 is negative, causing process deposition of material onto said process substrate and/or wittness substrate; and d) utilizing change in said monitored DELTA to control the deposition procedure. A modified embodiment of the disclosed invention is a method of controlling deposition or etching of thin layers of material to or from substrates comprising the steps of: a) providing a system for etching materials from a process substrate placed therewithin, including a system for providing a beam of P-polarized electromagnetism and orienting it to direct said beam at an oblique angle of incidence to a surface of said process substrate, and/or a wittness substrate, reflect therefrom and enter a detector for monitoring ellipsometric PSI and DELTA of said process substrate and/or wittness substrate, said process substrate or wittness substrate having a negative e1 at at least one wavelength; b) adjusting the angle of incidence of the electromagnetic beam to a surface of said process substrate and/or wittness substrate until a decrease of intensity is noted at the detector for said at least one wavelength at which the e1 is negative, indicating formation of a surface plasmon in said process substrate and/or wittness substrate; c) while monitoring at least the ellipsometric DELTA of said process substrate and/or wittness substrate at said at least one wavelength at which its e1 is negative, causing process etching of material from said process substrate and/or wittness substrate; and d) utilizing change in said monitored DELTA to control the etching procedure. Said disclosed invention can involve both deposition and etching, and can be recited as a method of controlling deposition or etching of thin layers of material to or from substrates comprising the steps of: a) providing a system for deposition and/or etching of materials onto or from a process substrate placed therewithin, including a system for providing a beam of P-polarized electromagnetism and orienting it to direct said beam at an oblique angle of incidence to a surface of said process substrate, and/or a wittness substrate, reflect therefrom and enter a detector for monitoring ellipsometric PSI and DELTA of said process substrate and/or wittness substrate, said process substrate or wittness substrate having a negative e1 at at least one wavelength; b) adjusting the angle of incidence of the electromagnetic beam to a surface of said process substrate and/or wittness substrate until a decrease of intensity is noted at the detector for said at least one wavelength at which the e1 is negative, indicating formation of a surface plasmon in said process substrate and/or wittness substrate; c) while monitoring at least the ellipsometric DELTA of said process substrate and/or wittness substrate at said at least one wavelength at which its e1 is negative, causing process deposition of and/or etching of material onto or from said process substrate and/or wittness substrate; and d) utilizing change in said monitored DELTA to control the deposition and/or etching procedure. In any of the foregoing recitals, the wavelength at which the DELTA is monitored is preferably selected to be that at which said DELTA demonstrates the greatest sensitivity to change in the process substrate. For instance, where the material deposited or etched is biological, wavelengths in the infrared can be utilized. In any of the foregoing recitals, the ellipsometric PSI of said process substrate and/or wittness substrate can also be monitored and change therein utilized in conjunction with said change in said monitored DELTA, to control the deposition and/or etching procedure in step d. In any of the foregoing recitals, the beam of electromagnetic radiation can be spectroscopic and the ellipsometric PSI of said process substrate and/or wittness substrate is also monitored and change therein utilized in conjunction with said change in said monitored DELTA, to control the deposition and/or etching procedure in step d, and in Which the monitored PSI and DELTA are determined at a selection from the group consisting of: the same wavelength; and different wavelengths; and preferably the wavelength chosen for monitoring at least one of said PSI and DELTA is that at which maximum sensitivty to process substrate change is demonstrated. In any of the foregoing recitals, said wittness substrate can be monitored and be a selection from the group consisting of: it is made from the same material as the process substrate; it is made from the same material as the process substrate, but is of a different thickness; it is made from a different material than the process substrate. In any of the foregoing recitals, said process and wittness substrates can each be independently selected from the group consisting of: gold; silver; iridium; silicon; gallium arsenide; dielectrics such as TiO2; gallium arsenide; semiconductor with surface insulator layer(s); doped semiconductor; compensated semiconductor; SiC; AIN; SiO2 (quartz); hexagonal BN; cubic BN; Graphite; Heavily doped binary, ternary, and quaternary alloys of compound 3/I semiconductors; In any of the foregoing recitals, said said process and wittness substrates can be substantially identical, and monitored during processing of the process substrate but not the wittness substrate, and in Which data obtained from the monitoring of the wittness substrate is subtracted from data obtained from the monitoring of the process substrate in determining change in DELTA of the process substrate. In any of the foregoing recitals, the beam of electromagnetic radiation can be spectroscopic; said said process and wittness substrates can be substantially identical and both are monitored during processing of the process substrate but into the wittness substrate; data obtained from the monitoring of the wittness substrate can be subtracted from data obtained from the monitoring of the process substrate in determining change in DELTA of the process substrate; and in which the ellipsometric DELTA is determined at more than one wavelength and utilized in control of the processing. Further, in any of the foregoing recitals, is to be understood that the beam of P-polarized electromagnetism caused to approach the substrate can have intentionally associated therewith at least some non-P-polarized, (eg. S-polarized) electromagnetism, either simultaneously, or sequentially. An S component allows perfoming conventional ellipsometric evaluation of a substrate as said S component is not affected by the Surface Plasma Resonance (SPR) phenomona. It is to be understood that the the procedure of obtaining ellipsometric data using P-Polarized electromagnetic radiation directed to a substrate surface at a Surface Plasmon Resonance Resonance angle-of-incidence to said sample surface, and simultaneously or sequentially obtaining conventional ellipsometric data using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said SPR Resonance angle-of-incidence; followed by analyzing said data to arrive at a thickness for deposited or removed material can be applied to samples which are already fabricated. Finally, while ellipsometric DELTA is generally more sensitive to layer thickness, and ellipsometric PSI is generally more sensitive to surface roughness and grading etc., it does occur that in some cases ellipsometric PSI provides better sensitivity to surface change than does ellipsometric DELTA. The foregoing recital focused on primary reference to ellipsometric DELTA, however, such is not always optimum. It is to be understood that in the foregoing, every instance of DELTA can be replaced with PSI and vice-versa and an alternative, and in some cases, superior, approach to monitoring surface change results. Claims which make this clear are presented herein. SUMMARY OF THE INVENTION It is therefore a purpose and/or objective of the disclosed invention to teach combined use of Surface Plasmon Resonance data which is obtained using P-Polarized electromagentic radiation directed to a substrate surface at a Resonance angle-of-incidence, and conventional ellipsometric data which is obtained using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said Resonance angle-of-incidence, in monitoring thin film deposition or removal from the surface of said substrate. It is another purpose and/or objective of the disclosed invention to teach combined use of Surface Plasmon Resonance data which is obtained using P-Polarized electromagentic radiation directed to a substrate surface at a Resonance angle-of-incidence, and conventional ellipsometric data which is obtained using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said Resonance angle-of-incidence, in controlling thin film deposition or removal from the surface of said substrate. Other purposes and/or objectives of the disclosed invention will become apparent from a reading of the Specification and Claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 demonstrates an Ellipsometer System. FIG. 2 a demonstrates a Substrate Processing Chamber. FIG. 2 b demonstrates a Substrate Processing Chamber with provision for changing Angle-of-Incidence of a beam. FIG. 2 c shows another approach to achieving multiple AOI's which can be applied in a FIG. 2 b Substrate Processing Chamber. FIG. 2 d demonstrates that a purged Substrate Processing Chamber. FIG. 2 e shows a Cell comprising a surface (SUR) of a sample stage element (STG) which is provided electromagnetic radiation EMI and EMI′ from a single source, and further indicates reflected beams EMO and EMO′ can be directed to one or more Detector(s). FIGS. 3 a and 3 b demonstrate ellipsometric PSI and DELTA for BK7 Glass with 50 nm of Gold on its surface, as a function of Angle-of-Incidence, and at 680, 730 and 780 nm. FIGS. 4 a - 4 h demonstrate ellipsometric PSI and DELTA vs. Wavelength, at Angles-of-Incidence of 66, 70 and 74 degrees to a BK-7 Glass Prism upon which is deposited Gold. FIGS. 5 a and 5 b show expanded forms of FIGS. 4 a and 4 f . DETAILED DESCRIPTION To begin, for general insight it should be appreciated that FIG. 1 demonstrates an ellipsometer system which can be applied to investigate a substrate sytsem (SS). Shown for both Reflection and Transmission are, sequentially: a. a Source of a beam electromagnetic radiation (LS); b. a Polarizer element (P); c. optionally a compensator element (C 1 ); d. (additional element(s)) (AC 1 ); e. a substrate system (SS); f. (additional element(s)) (AC 2 ); g. optionally a compensator element (C 2 ); h. an Analyzer element (A); and i. a Detector System (DET). It is noted that the elements identified as (LS), (P) and (C 1 ) can be considered to form, as a group, a Polarization State Generator (PSG), and the components (C 2 ), (A) and (DET) can be considered, as a group, to form a Polarization State Detector (PSD). It is to be understood that the d. and f. “additional elements”, (AC 1 ) and (AC 2 ), can be considered as being, for the purposes of the disclosed invention Disclosure, Substrate Process Chamber Input (WI) and Output (WO) Window means. Note the locations of electromagnetic beams (EMI) and (EMO). FIG. 2 a shows a Substrate Process Chamber (1V) with a Substrate (SS) present therein, and including means indicated as (HI) and (LO), each with a Shutter (SH) and (SL) associated therewith, for effecting Substrate (SS) processing, such as fabrication of Multi-layer Interference Band-pass and Band-reject Filters by deposition of materials. The Process Chamber could also be applied to etching of material from the surface of substrates. Affixed to the Substrate Process Chamber (1V) is a Reflection Mode Ellipsometer as shown in FIG. 1 . Note the positioning of (AC 1 ) and (AC 2 ) in both FIGS. 1 and 2 for coordination, and that an incident beam (PPCLB) approaches Substrate (SS) and a beam (EPCLB) reflected from said Substrate. While not specifically shown, (it is not the purpose of this Disclosure to describe suitable beam entry and exit means which allow change of the angles of incidence and abd reflection), the FIG. 2 b is shown as a possible, non-limiting, configuration which allows change in the angles of incident beam (PPCLB) and reflected beam (EPCLB). Such can be achieved by, for instance, providing the shown curved (AC 1 ) and (AC 2 ) Windows, (or any functional equivalent), at the right and left sides of the Substrate Process Chamber (1V) which allow beam passage at various Angles of Incidence and Reflection (not shown). This is because in practice of the disclosed invention it is important to have the capability of changing said Angles, in order to arrive at the AOI at which the Surface Plasmon Resonance occurs. FIG. 2 b also can be taken to show that two Electromagnetic Radiation Source and Polarizer combinations (PSG's) can be applied, one P-Polarized, and the other not P-Polarized. In practice the P-Polarized beam can be set to be incident on a Sample Surface at the SPR Resonance angle, and another Polarized beam, (eg. can be non-P-Polarized), at an angle perhaps closer to the Brewster angle. Said second Polarized beam can actually be P-Polarized if it is not incident on the sample surface at the SPR Resonant Angle. Both SPR and Conventional Ellipsometric analysis can then be conducted with the two Polarized beams being simultaneously, or sequentially applied. FIG. 2 c shows another approach to achieving multiple AOI's. A single Colimated (COL) beam can be focused onto a Sample (S), and said input can result in multiple Angles-of-Reflection (AOR's), each of which can be intercepted by different Dispersive Optics, (DO 1 ), (DO 2 ), (DO 3 ), (DO 4 ) and (DO 5 ) and a wavelengths spectrum from each directed into a separate Detectors (DET 1 ), (DET 2 ), (DET 3 ), (DET 4 ) AND (DET 5 ), respectively. Such an arrangement can be applied, via windows, to a Substrate Process Chamber (1V). FIG. 2 c also indicates a De-focusing means (DF) can be present to prevent focusing effects of the curved Window (AC 1 ) on a beam of electromagneic radiation passing therethrough. FIG. 2 d demonstrates that an alternative to providing windows (AC 1 ) (AC 2 ) through which electromagnetic radiation passes, as shown in FIG. 2 b and is necessary where the Substrate Process Chamber (1V) is evacuated, is to provide a purged Substrate Process Chamber (1V′). The FIG. 2 d embodiment shows Purge Gas (PG) being flowed through Tubes (T 1 ) (T 2 ) through which the incident beam (PPCLB) and reflected beam (EPCLB) electromagnetic beams are passed. The Tubes (T 1 ) and (T 2 ) can be secured to the Purged Substrate Process Chamber (1V′) by any means which minimizes escape of the Purging Gas (PG), while allowing change of the AOI and AOR. Use of Purged (1V′) rather than evacuated Substrate Process Chamber (1V) can be valuable in, for instance, Chemical Vapor Deposition (CVD) fabrication settings. The described invention can then be practiced in evacuated or purged Substrate Process Chamber (1V) environments. FIG. 2 e shows a (Cell) comprising a surface (SUR) of a sample stage element (STG) which is provided electromagnetic radiation EMI and EMI′ or EMI″ from a single source via divider means, (or separate sources could be used), and further indicates reflected beams EMO and EMO′ are directed to one or more Detector(s). The upper half of said (CELL) is a more conventional system applied in SPR research. It is to be understood that the electromagnetic beams EMI and EMI′ can comprise the same or different wavelength content. For instance, the same wavelength content can be present in EMI and EMI″ and different angles-of-incidence from above and below utilized, as indicated by EMI and dashed line EMI″. Different wavelength content can also be present in EMI and EMI″. Where different wavelength content is present, the beams EMI and EMI′ can be applied at the same angle-of-incidence, however, in this case the same wavelength content could be present and the purpose behind the configuration being solely to gain data pertaining to top and bottom aspects of a sample atop the surface of the sample stage element (STG). Normal angle of incidence electromagnetic beam EMI′″ is indicated as present as well, but no Polarizer or Analyzer is typically present in the EMI′″ beam locus. That is EMI′″ is a Transmission Intensity beam used to monitor sample absorbance. Note that optical fibers (F) and Couplers (COUP) can be utilized to guide incident and reflected electromagnetic beams. Also note that Analyzer(s) (A), Polarizers (P) and optional Compensator(s) (C 1 ) (C 2 ) along with the Detectors(s) indicated as shown in FIG. 1 , are assumed present in FIG. 2 e as functionally required. Note, where different wavelengths are to be provided in the multiple electromagnetic beams, utilizing a single source of electromagnetic radiation in combination with Couplers which including functional filtering means, is a possibility. In use fluid containing analyte (SSF) is flowed into (SI) and exits via (SO). Analyte deposits onto the Upper Surface between the “OR” rings and Surface Plasmon Resonance and and Conventional Elipsometry techniques can be applied in analysis as desxcribe above with respect to other systems. Calculated results are shown in FIGS. 3 a , 3 b , 4 a - 4 h and 5 a and 5 b , for Gold deposited onto BK-7 Glass. Said results are exemplary of how ellipsometric PSI and DELTA provide very high sensitivity to surface change at a Surface Plasmon Resonance (SPR) angle-of-incidence. FIGS. 3 a and 3 b demonstrate ellipsometric PSI and DELTA for BK7 Glass with 50 nm of Gold on its surface, as a function of Angle-of-Incidence, and at 680, 730 and 780 nm. Note in particular the very steep slope of the FIG. 3 b DELTA vs. AOI. FIGS. 4 a - 4 h demonstrate ellipsometric PSI and DELTA vs. Wavelength, at Angles-of-Incidence of 66, 70 and 74 degrees to a BK-7 Glass Prism upon which is deposited Gold. FIGS. 4 a and 4 b show ellipsometric PSI and DELTA for the case where 100 nm of Gold is deposited onto the investigated surface, FIGS. 4 c and 4 d show the results where 80 nm of Gold is deposited, FIGS. 4 e and 4 f show the case where 50 nm of Gold are present and FIGS. 4 g and 4 h show the results for the case where 40 nm of Gold is present. Note in FIG. 4 f the very steep slope in DELTA for the 66 and 70 Degree AOI's, which is not present in the other, (ie. 4 b , 4 d and 4 h DELTA plots). Where results like shown in FIG. 4 f are present the ellipsometric DELTA provides extremely high sensitivity to change in surface properties of a sample. However, FIGS. 4 b , 4 d and 4 h show that the steep slope in ellipsometric DELTA is not always observed. FIGS. 4 a , 4 c , 4 e and 4 g show that reasonable sensitivity in ellipsometric PSI is present for all thicknesses of Gold. FIGS. 5 a and 5 b show expanded forms of FIGS. 4 e and 4 f. It should be appreciated that the disclosed invention can be applied to fabrication of thin films via deposition of material onto, or etching material from a substrate, as well as in monitoring analyte material which deposits onto a stage from an analyte containing fluid, (eg. liquid), sample. The very high sensitivity of ellipsometric PSI and/or DELTA at an SPR condition enhances the capability of ellipsometry to detect very thin layers of material deposited onto or removed from a substrate. It is also disclosed that the described methodology can be applied to samples after they have been fabricated. The terminology “Plasmon” is to be interpreted sufficiently broadly to include “Polaritons”. It is also conceived that the extra data provided by plasmons or polaritrons could serve to break correlation between thickness and refractive index, which correlation is inherrant in conventional single sample analysis ellipsometry. Having hereby disclosed the subject matter of the present invention, it should be obvious that many modifications, substitutions, and variations of the present invention are possible in view of the teachings. It is therefore to be understood that the invention may be practiced other than as specifically described, and should be limited in its breadth and scope only by the Claims.
Improved methodology for monitoring deposition or removal of material to or from a process and/or wittness substrate which demonstrates a negative e 1 at some wavelength. The method involves detection of changes in P-polarized electromagnetism ellipsometric DELTA at SPR Resonance Angle-of-Incidence (AOI) to monitor deposition of and/or removal of minute amounts of materials onto, or from, said process and/or witness substrate. The methodology can optionally monitor ellipsometric PSI, and involves simultaneously or sequentially applying non-P-polarized electromagnetism at the same angle of incidence, or electromagnetic radiation of any polarization at a different angle-of-incidence and wavelength to the process or wittness substrate and application of conventional ellipsometric analysis.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "This application is a Continuation-In-Part of application Ser.", "No. 10/238,241 Filed Sep. 10, 2002 now U.S. Pat. No. 6,937,341, and of Ser.", "No. 09/756,515 Filed Jan. 9, 2001 now U.S. Pat. No. 6,455,853, and therevia Claims benefit of Provisional Application Ser.", "No. 60/183,977 Filed Feb. 22, 2000.", "This Application is further a Continuation-In-Part of application Ser.", "No. 09/162,217, now U.S. Pat. No. 6,034,777, Filed Sep. 29, 1998 via Pending application Ser.", "Nos. 10/829,620, Filed Apr. 22, 2004, and 10/925,333 Filed Aug. 24, 2004, and 09/419,794, Filed Oct. 18, 1999 (now U.S. Pat. No. 6,549,282), which was a CIP of said 777 Patent.", "This Application directly Claims benefit from Provisional Applications 06/609,339, Filed Sep. 14, 2004;", "60/598,456, Filed Aug. 3, 2004, and 60/530,416, Filed Dec. 17, 2003.", "TECHNICAL FIELD The disclosed invention relates to methodology for monitoring thin film deposition or removal from the surface of a substrate, and more particularly to methodology which combines Surface Plasmon Resonance (SPR) and Spectroscopic Ellipsometry (SE) techniques, involving use of process and/or wittness substrates with negative dielectric function e1, and small e2 in a specified wavelength range.", "Said method involves detection of changes in Ellipsometric Polarization State, (eg.", "DELTA or PSI), when P-polarized is caused to interact with a Sample at an Surface Plasmon inducing Resonant Angel-of-Incidence (AOI) to monitor deposition of and/or removal of minute amounts of materials onto, or from, a process and/or witness substrate, said monitoring being in combination with applying non-P Polarized electromagnetic radiation at the SPR resonance angle-of-incidence, and/or electromagnetic radiation of any polarization state at another angle-of-incidence, and conducting conventional ellipsometric analysis thereof simultaneously or sequentially.", "BACKGROUND Surface Plasmon Resonance (SPR) is a well-known optical diagnostics method used extensively by biologists to sensitively measure changes at surfaces.", "For insight it is noted that normally electromagnetic radiation reflects speculatly from smooth surfaces, or diffusely from rough surfaces, or reflects with combined specular and diffuse components.", "Surface Plasmon Resonance (SPR) refers to an unusual condition under which the light, rather than being immediately reflected, is absorbed and induces a surface “plasmon”", "or the like wave in the material.", "This occurs when using, for example, a gold film, and P-Polarized visible light (of say 650 nm wavelength) is caused to impinge upon thereupon at an SPR resonance angle of incidence of about 50 degrees to the normal to a surface thereof.", "This is described as a “resonant”", "condition for SPR.", "The P-Polarized light, (eg.", "which can comprise electromagnetic radiation of any functional wavelength), sets up a surface plasmon traveling wave along the surface of a metal.", "To date, SPR invariably uses either gold, silver, or other common metal for which plasmons are excited mainly by visible light.", "That is, the atomic nature of the material (metal) determines the resonant angle.", "In scientific terms, SPR can be performed on any material for which the real-part of the complex dielectric function (e1) is less than zero, in a wavelength region wherein imaginary part (e2) of the is complex dielectric function is not too great.", "Materials with negative real-part of dielectric function is useful wavelength ranges include especially low-mass materials, such as SiC, and Si-oxides.", "For example, SiC with real-part of dielectric constant.", "negative in spectral range 960 cm −1 to 780 cm −1 , and AIN has range 610 cm −I to 800 cm −1 negative dielectric function.", "SiO2 (quartz) is 1161 cm−1 to 1236 cm −1 .", "Hexagonal BN has useful ranges 1510 cm −1 to 1595 cm−1 and 1367 cm −1 to 1610 cm −1 , and cubic BN in range 1060 cm−1 to 1430 cm −1 .", "Graphite has possible resonance 867.8 cm−1 to 868.1 cm −1 ;", "narrow but potentially useful.", "Heavily doped binary, ternary, and quaternary alloys of compound 3/I semiconductors move the resonance into the useful 2 to 18 micron spectral range (555 cm −1 to 5000 cm −1 ) for biological materials (see attached review article table and graphs).", "Other examples might be intercalation compounds of graphite, which dope as both donors and acceptors.", "Metals have negative real-part of dielectric function negative at long-wavelengths, but are difficult to excite, but are possibly useful for these measurements, especially ultra-smooth metals such as Ir.", "Continuing, SPR can, sense both the time rate of change and the amount of attachment of biomaterial to a metal substrate.", "SPR is a known valuable method for development of new drug-release surfaces;", "development of sensors for toxins, bio-warfare threats, and diseases, development of new materials for implants in humans (such as stints and heart valves), and for numerous other biomedical and bioengineering applications.", "SPR is hundreds of times more sensitive than conventional spectroscopies for thin films.", "One example, (of hundreds), is in the monitoring of the attachment of toxins, (such as cholera), to surfaces functionallized by IgG protein.", "To date most applications have been in bio-material monitoring.", "While the herein disclosed invention can be used in any material system investigation system such as Polarimeter, Reflectomerter, Spectrophotometer and the like Systems, an important application is with Ellipsometer Systems, whether monochromatic or spectroscopic.", "It should therefore be understood that Ellipsometry involves acquisition of sample system characterizing data at single or multiple Wavelengths, and at one or more Angle(s)-of-Incidence (AOI) of a Beam of Electromagnetic Radiation to a surface of the sample system.", "Ellipsometry is generally well described in a great many publication, one such publication being a review paper by Collins, titled “Automatic Rotating Element Ellipsometers: Calibration, Operation and Real-Time Applications”, Rev. Sci.", "Instrum.", ", 61(8) (1990).", "A typical goal in ellipsometry is to obtain, for each wavelength in, and angle of incidence of said beam of electromagnetic radiation caused to interact with a sample system, sample system characterizing PSI and DELTA values, where PSI is related to a change in a ratio of magnitudes of orthogonal components r p /r s in said beam of electromagnetic radiation, and wherein DELTA is related to a phase shift entered between said orthogonal components r p and r s , caused by interaction with said sample system.", "This is expressed by: TAN(ψ) e i(Δ) =r s /r p .", "(Note the availability of the phase DELTA (Δ) data is a distinguishing factor between ellipsometry and reflectometry).", "Ellipsometer Systems generally include a source of a beam of electromagnetic radiation, a Polarizer, which serves to impose a state of polarization on a beam of electromagnetic radiation, a Stage for supporting a sample system, and an Analyzer which serves to select a polarization state in a beam of electromagnetic radiation after it has interacted with a material system, and passed it to a Detector System for analysis therein.", "As well, one or more Compensator(s) can be present and serve to affect a phase angle between orthogonal components of a polarized beam of electromagnetic radiation.", "A number of types of ellipsometer systems exist, such as those which include rotating elements and those which include modulation elements.", "Those including rotating elements include Rotating Polarizer (RP), Rotating Analyzer (RA) and Rotating Compensator (RC).", "A preferred embodiment is a Rotating Compensator Ellipsometer System because, it is noted, Rotating Compensator Ellipsometer Systems do not demonstrate “Dead-Spots”", "where obtaining data is difficult.", "They can read PSI and DELTA of a Material System over a full Range of Degrees with the only limitation being that if PSI becomes essentially zero (0.0), DELTA can not then be determined as there is not sufficient PSI Polar Vector Length to form the angle between the PSI Vector and an “X”", "axis.", "In comparison, Rotating Analyzer and Rotating Plarizer Ellipsometers have “Dead Spots”", "at DELTA's near 0.0 or 180 Degrees and Modulation Element Ellipsometers also have “Dead Spots”", "at PSI near 45 Degrees).", "The utility of Rotating Compensator Ellipsometer Systems should then be apparent.", "Another benefit provided by fixed Polarizer (P) and Analyzer (A) positions is that polarization state sensitivity to input and output optics during data acquisition is essentially non-existent.", "This enables relatively easy use of optic fibers, mirrors, lenses etc.", "for input/output.", "Further, it is to be understood that causing a polarized beam of electromagnetic radiation to interact with a sample system generally causes change in the ratio of the intensities of orthogonal components thereof and/or the phase angle between said orthogonal components.", "The same is generally true for interaction between any system component and a polarized beam of electromagnetic radiation.", "In recognition of the need to isolate the effects of an investigated sample system from those caused by interaction between a beam of electromagnetic radiation and system components other than said sample system, (to enable accurate characterization of a sample system per se.), this Specification incorporates by reference the regression procedure of U.S. Pat. No. 5,872,630 to Johs et al.", "in that it describes simultaneous evaluation of sample characterizing parameters such as PSI and DELTA, as well system characterizing parameters, and this Specification also incorporates by reference the Vacuum Chamber Window Correction methodology of U.S. Pat. No. 6,034,777 to Johs et al.", "to account for phase shifts entered between orthogonal components of a beam of electromagnetic radiation, by disclosed invention system windows and/or beam entry elements.", "For insight, one embodiment of said method of accurately evaluating parameters in parameterized equations in a mathematical model of a system of spatially separated input and output windows, said parameterized equations enabling, when parameters therein are properly evaluated, independent calculation of retardation entered by each of said input window and said output window between orthogonal components of a beam of electromagnetic radiation caused to pass through said input and output windows, at least one of said input and output windows being birefringent, said method comprises, in a functional order, the steps of: a. providing spatially separated input and output windows, at least one of said input and output windows demonstrating birefringence when a beam of electromagnetic radiation is caused to pass therethrough, there being a means for supporting a sample system positioned between said input and output windows;", "b. positioning an ellipsometer system source of electromagnetic radiation and an ellipsometer system detector system such that in use a beam of electromagnetic radiation provided by said source of electromagnetic radiation is caused to pass through said input window, interact with said sample system in a plane of incidence thereto, and exit through said output window and enter said detector system;", "c. providing a sample system to said means for supporting a sample system, the composition of said sample system being sufficiently well known so that retardence entered thereby to a polarized beam of electromagnetic radiation of a given wavelength, which is caused to interact with said sample system in a plane of incidence thereto, can be accurately modeled mathematically by a parameterized equation which, when parameters therein are properly evaluated, allows calculation of retardence entered thereby between orthogonal components of a beam of electromagnetic radiation caused to interact therewith in a plane of incidence thereto, given wavelength;", "d. providing a mathematical model for said ellipsometer system and said input and output windows and said sample system, comprising separate parameterized equations for independently calculating retardence entered between orthogonal components of a beam of electromagnetic radiation caused to pass through each of said input and output windows and interact with said sample system in a plane of incidence thereto;", "such that where parameters in said mathematical model are properly evaluated, retardence entered between orthogonal components of a beam of electromagnetic which passes through each of said input and output windows and interacts with said sample system in a plane of incidence thereto can be independently calculated from said parameterized equations, given wavelength;", "e. obtaining a spectroscopic set of ellipsometric data with said parameterizable sample system present on the means for supporting a sample system, utilizing a beam of electromagnetic radiation provided by said source of electromagnetic radiation, said beam of electromagnetic radiation being caused to pass through said input window, interact with said parameterizable sample system in a plane of incidence thereto, and exit through said output window and enter said detector system;", "f. by utilizing said mathematical model provided in step d. and said spectroscopic set of ellipsometric data obtained in step e., simultaneously evaluating parameters in said mathematical model parameterized equations for independently calculating retardence entered between orthogonal components in a beam of electromagnetic radiation caused to pass through said input window, interact with said sample system in a plane of incidence thereto, and exit through said output window;", "to the end that application of said parameterized equations for each of said input window, output window and sample system for which values of parameters therein have been determined in step f., enables independent calculation of retardence entered between orthogonal components of a beam of electromagnetic radiation by each of said input and output windows, and said sample system, at given wavelengths in said spectroscopic set of ellipsometric data, said calculated retardence values for each of said input window, output window and sample system being essentially uncorrelated.", "No known references teach combined use of Surface Plasmon Resonance data which is obtained using P-Polarized electromagnetic radiation directed to a substrate surface at a Resonance angle-of-incidence, and conventional ellipsometric data which is obtained using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said Resonance angle-of-incidence, in monitoring and optionally controlling thin film deposition or removal from the surface of said substrate.", "DISCLOSURE OF THE INVENTION The present invention recognizes that while Ellipsometry provides sensitivity to layers of material on the order of a nonometer, additional sensitivity to even thinner layers would be of benefit.", "The present invention provides for the use of the Surface Plasmon Resonance (SPR) effect in the monitoring of deposition or etching of thin layers of material, either independently or in symbiotic combination with practice of conventional ellipsometry.", "It is noted that the SPR technique requires that P-Polarized electromagnetic radiation be applied, whereas conventional ellipsometry can utilize any polarization orientation.", "The present invention then provides for application of P-Polarized and Non-P-Polarized electromagnetic radiation, simultaneously or sequentially, to a sample during deposition or removal of one or more thin films on a surface thereof.", "A primary embodiment of the method of monitoring the deposition or removal of material from the surface of a substrate comprising the steps of: a) while material is being deposited or removed from said substrate surface, by causing electromagnetic radiation to impinge on, interact with and then enter a detector: obtaining ellipsometric data using P-Polarized electromagnetic radiation directed to a substrate surface at a Surface Plasmon Resonance Resonance angle-of-incidence to said sample surface, and simultaneously or sequentially obtaining conventional ellipsometric data using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said SPR Resonance angle-of-incidence;", "b) analyzing said data to arrive at a thickness for deposited or removed material.", "Said method can further comprise the step of controlling deposition or removal of material using said ellipsometric data.", "Said method can involve said ellipsometric data obtained using P-Polarized electromagnetic radiation at the SPR resonance angle-of-incidence and data, and said ellipsometric data simultaneously or sequentially obtaining using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said SPR Resonance angle-of-incidence, being analyzed simultaneously.", "Another embodiment of the present invention is a method of monitoring deposition of, or etching of material from a sample surface comprising the steps of: a) providing an ellipsometer system comprising a source of electromagnetic radiation, a polarizer, a sample supporting stage, an analyzer and a detector and means for changing the angle-of-incidence at which the beam approaches said sample surface;", "a) placing a sample onto said sample supporting stage and by adjusting said polarizer, providing incident P-Polarized electromagnetic radiation to said sample surface, and while monitoring P-Polarized electromagnetic radiation reflected from said sample surface adjusting the angle-of-incidence until surface plasmon resonance occurs as evidenced by a large change in intensity or a determined ellipsometric PSI and/or DELTA, thereby indicating that the surface plasmon resonance angle-of-incidence has been identified;", "b) while depositing material onto or etching material from said sample surface, monitoring change in the ellipsometric PSI and/or DELTA which results from the P-Polarized electromagnetic radiation;", "c) said method further comprising providing incident non-P-Polarized electromagnetic radiation at the SPR Resonance, or another angle-of-incidence onto said sample surface such that it reflects into the same, or another detector, and determining a conventional ellipsometric PSI and/or DELTA therefrom;", "such that changes in said ellipsometric PSI's and/or DELTA's resulting from the P-Polarized and from the non-P-Polarized beams indicate deposition of, or etching of material from said sample surface.", "It is noted that the P-Polarized and non-P-Polarized electromagnetic radiation can be simultaneously or sequentially applied to said sample surface, at the same, or at different angles-of-incidence.", "Also, where bio-materials are involved, the P-Polarized and non-P-Polarized electromagnetic radiation can comprise infrared wavelengths.", "Still another embodiment of the presently disclosed invention is a method of controlling deposition or etching of thin layers of material to or from substrates comprising the steps of: a) providing a system for deposition of materials onto a process substrate placed therewithin, including a system for providing a beam of P-polarized electromagnetism and orienting it to direct said beam at an oblique angle of incidence to a surface of said process substrate, and/or a wittness substrate, reflect therefrom and enter a detector for monitoring ellipsometric PSI and DELTA of said process substrate and/or wittness substrate, said process substrate or wittness substrate having a negative e1 at at least one wavelength;", "b) adjusting the angle of incidence of the electromagnetic beam to a surface of said process substrate and/or wittness substrate until a decrease of intensity is noted at the detector for said at least one wavelength at which the e1 is negative, indicating formation of a surface plasmon in said process substrate and/or wittness substrate;", "c) while monitoring at least the ellipsometric DELTA of said process substrate and/or wittness substrate at said at least one wavelength at which its e1 is negative, causing process deposition of material onto said process substrate and/or wittness substrate;", "and d) utilizing change in said monitored DELTA to control the deposition procedure.", "A modified embodiment of the disclosed invention is a method of controlling deposition or etching of thin layers of material to or from substrates comprising the steps of: a) providing a system for etching materials from a process substrate placed therewithin, including a system for providing a beam of P-polarized electromagnetism and orienting it to direct said beam at an oblique angle of incidence to a surface of said process substrate, and/or a wittness substrate, reflect therefrom and enter a detector for monitoring ellipsometric PSI and DELTA of said process substrate and/or wittness substrate, said process substrate or wittness substrate having a negative e1 at at least one wavelength;", "b) adjusting the angle of incidence of the electromagnetic beam to a surface of said process substrate and/or wittness substrate until a decrease of intensity is noted at the detector for said at least one wavelength at which the e1 is negative, indicating formation of a surface plasmon in said process substrate and/or wittness substrate;", "c) while monitoring at least the ellipsometric DELTA of said process substrate and/or wittness substrate at said at least one wavelength at which its e1 is negative, causing process etching of material from said process substrate and/or wittness substrate;", "and d) utilizing change in said monitored DELTA to control the etching procedure.", "Said disclosed invention can involve both deposition and etching, and can be recited as a method of controlling deposition or etching of thin layers of material to or from substrates comprising the steps of: a) providing a system for deposition and/or etching of materials onto or from a process substrate placed therewithin, including a system for providing a beam of P-polarized electromagnetism and orienting it to direct said beam at an oblique angle of incidence to a surface of said process substrate, and/or a wittness substrate, reflect therefrom and enter a detector for monitoring ellipsometric PSI and DELTA of said process substrate and/or wittness substrate, said process substrate or wittness substrate having a negative e1 at at least one wavelength;", "b) adjusting the angle of incidence of the electromagnetic beam to a surface of said process substrate and/or wittness substrate until a decrease of intensity is noted at the detector for said at least one wavelength at which the e1 is negative, indicating formation of a surface plasmon in said process substrate and/or wittness substrate;", "c) while monitoring at least the ellipsometric DELTA of said process substrate and/or wittness substrate at said at least one wavelength at which its e1 is negative, causing process deposition of and/or etching of material onto or from said process substrate and/or wittness substrate;", "and d) utilizing change in said monitored DELTA to control the deposition and/or etching procedure.", "In any of the foregoing recitals, the wavelength at which the DELTA is monitored is preferably selected to be that at which said DELTA demonstrates the greatest sensitivity to change in the process substrate.", "For instance, where the material deposited or etched is biological, wavelengths in the infrared can be utilized.", "In any of the foregoing recitals, the ellipsometric PSI of said process substrate and/or wittness substrate can also be monitored and change therein utilized in conjunction with said change in said monitored DELTA, to control the deposition and/or etching procedure in step d. In any of the foregoing recitals, the beam of electromagnetic radiation can be spectroscopic and the ellipsometric PSI of said process substrate and/or wittness substrate is also monitored and change therein utilized in conjunction with said change in said monitored DELTA, to control the deposition and/or etching procedure in step d, and in Which the monitored PSI and DELTA are determined at a selection from the group consisting of: the same wavelength;", "and different wavelengths;", "and preferably the wavelength chosen for monitoring at least one of said PSI and DELTA is that at which maximum sensitivty to process substrate change is demonstrated.", "In any of the foregoing recitals, said wittness substrate can be monitored and be a selection from the group consisting of: it is made from the same material as the process substrate;", "it is made from the same material as the process substrate, but is of a different thickness;", "it is made from a different material than the process substrate.", "In any of the foregoing recitals, said process and wittness substrates can each be independently selected from the group consisting of: gold;", "silver;", "iridium;", "silicon;", "gallium arsenide;", "dielectrics such as TiO2;", "gallium arsenide;", "semiconductor with surface insulator layer(s);", "doped semiconductor;", "compensated semiconductor;", "SiC;", "AIN;", "SiO2 (quartz);", "hexagonal BN;", "cubic BN;", "Graphite;", "Heavily doped binary, ternary, and quaternary alloys of compound 3/I semiconductors;", "In any of the foregoing recitals, said said process and wittness substrates can be substantially identical, and monitored during processing of the process substrate but not the wittness substrate, and in Which data obtained from the monitoring of the wittness substrate is subtracted from data obtained from the monitoring of the process substrate in determining change in DELTA of the process substrate.", "In any of the foregoing recitals, the beam of electromagnetic radiation can be spectroscopic;", "said said process and wittness substrates can be substantially identical and both are monitored during processing of the process substrate but into the wittness substrate;", "data obtained from the monitoring of the wittness substrate can be subtracted from data obtained from the monitoring of the process substrate in determining change in DELTA of the process substrate;", "and in which the ellipsometric DELTA is determined at more than one wavelength and utilized in control of the processing.", "Further, in any of the foregoing recitals, is to be understood that the beam of P-polarized electromagnetism caused to approach the substrate can have intentionally associated therewith at least some non-P-polarized, (eg.", "S-polarized) electromagnetism, either simultaneously, or sequentially.", "An S component allows perfoming conventional ellipsometric evaluation of a substrate as said S component is not affected by the Surface Plasma Resonance (SPR) phenomona.", "It is to be understood that the the procedure of obtaining ellipsometric data using P-Polarized electromagnetic radiation directed to a substrate surface at a Surface Plasmon Resonance Resonance angle-of-incidence to said sample surface, and simultaneously or sequentially obtaining conventional ellipsometric data using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said SPR Resonance angle-of-incidence;", "followed by analyzing said data to arrive at a thickness for deposited or removed material can be applied to samples which are already fabricated.", "Finally, while ellipsometric DELTA is generally more sensitive to layer thickness, and ellipsometric PSI is generally more sensitive to surface roughness and grading etc.", ", it does occur that in some cases ellipsometric PSI provides better sensitivity to surface change than does ellipsometric DELTA.", "The foregoing recital focused on primary reference to ellipsometric DELTA, however, such is not always optimum.", "It is to be understood that in the foregoing, every instance of DELTA can be replaced with PSI and vice-versa and an alternative, and in some cases, superior, approach to monitoring surface change results.", "Claims which make this clear are presented herein.", "SUMMARY OF THE INVENTION It is therefore a purpose and/or objective of the disclosed invention to teach combined use of Surface Plasmon Resonance data which is obtained using P-Polarized electromagentic radiation directed to a substrate surface at a Resonance angle-of-incidence, and conventional ellipsometric data which is obtained using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said Resonance angle-of-incidence, in monitoring thin film deposition or removal from the surface of said substrate.", "It is another purpose and/or objective of the disclosed invention to teach combined use of Surface Plasmon Resonance data which is obtained using P-Polarized electromagentic radiation directed to a substrate surface at a Resonance angle-of-incidence, and conventional ellipsometric data which is obtained using other than P-Polarized electromagentic radiation applied at said SPR Resonance angle-of-incidence, or electromagneic radiation of any Polarization applied at other than said Resonance angle-of-incidence, in controlling thin film deposition or removal from the surface of said substrate.", "Other purposes and/or objectives of the disclosed invention will become apparent from a reading of the Specification and Claims.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 demonstrates an Ellipsometer System.", "FIG. 2 a demonstrates a Substrate Processing Chamber.", "FIG. 2 b demonstrates a Substrate Processing Chamber with provision for changing Angle-of-Incidence of a beam.", "FIG. 2 c shows another approach to achieving multiple AOI's which can be applied in a FIG. 2 b Substrate Processing Chamber.", "FIG. 2 d demonstrates that a purged Substrate Processing Chamber.", "FIG. 2 e shows a Cell comprising a surface (SUR) of a sample stage element (STG) which is provided electromagnetic radiation EMI and EMI′ from a single source, and further indicates reflected beams EMO and EMO′ can be directed to one or more Detector(s).", "FIGS. 3 a and 3 b demonstrate ellipsometric PSI and DELTA for BK7 Glass with 50 nm of Gold on its surface, as a function of Angle-of-Incidence, and at 680, 730 and 780 nm.", "FIGS. 4 a - 4 h demonstrate ellipsometric PSI and DELTA vs.", "Wavelength, at Angles-of-Incidence of 66, 70 and 74 degrees to a BK-7 Glass Prism upon which is deposited Gold.", "FIGS. 5 a and 5 b show expanded forms of FIGS. 4 a and 4 f .", "DETAILED DESCRIPTION To begin, for general insight it should be appreciated that FIG. 1 demonstrates an ellipsometer system which can be applied to investigate a substrate sytsem (SS).", "Shown for both Reflection and Transmission are, sequentially: a. a Source of a beam electromagnetic radiation (LS);", "b. a Polarizer element (P);", "c. optionally a compensator element (C 1 );", "d. (additional element(s)) (AC 1 );", "e. a substrate system (SS);", "f. (additional element(s)) (AC 2 );", "g. optionally a compensator element (C 2 );", "h. an Analyzer element (A);", "and i. a Detector System (DET).", "It is noted that the elements identified as (LS), (P) and (C 1 ) can be considered to form, as a group, a Polarization State Generator (PSG), and the components (C 2 ), (A) and (DET) can be considered, as a group, to form a Polarization State Detector (PSD).", "It is to be understood that the d. and f. “additional elements”, (AC 1 ) and (AC 2 ), can be considered as being, for the purposes of the disclosed invention Disclosure, Substrate Process Chamber Input (WI) and Output (WO) Window means.", "Note the locations of electromagnetic beams (EMI) and (EMO).", "FIG. 2 a shows a Substrate Process Chamber (1V) with a Substrate (SS) present therein, and including means indicated as (HI) and (LO), each with a Shutter (SH) and (SL) associated therewith, for effecting Substrate (SS) processing, such as fabrication of Multi-layer Interference Band-pass and Band-reject Filters by deposition of materials.", "The Process Chamber could also be applied to etching of material from the surface of substrates.", "Affixed to the Substrate Process Chamber (1V) is a Reflection Mode Ellipsometer as shown in FIG. 1 .", "Note the positioning of (AC 1 ) and (AC 2 ) in both FIGS. 1 and 2 for coordination, and that an incident beam (PPCLB) approaches Substrate (SS) and a beam (EPCLB) reflected from said Substrate.", "While not specifically shown, (it is not the purpose of this Disclosure to describe suitable beam entry and exit means which allow change of the angles of incidence and abd reflection), the FIG. 2 b is shown as a possible, non-limiting, configuration which allows change in the angles of incident beam (PPCLB) and reflected beam (EPCLB).", "Such can be achieved by, for instance, providing the shown curved (AC 1 ) and (AC 2 ) Windows, (or any functional equivalent), at the right and left sides of the Substrate Process Chamber (1V) which allow beam passage at various Angles of Incidence and Reflection (not shown).", "This is because in practice of the disclosed invention it is important to have the capability of changing said Angles, in order to arrive at the AOI at which the Surface Plasmon Resonance occurs.", "FIG. 2 b also can be taken to show that two Electromagnetic Radiation Source and Polarizer combinations (PSG's) can be applied, one P-Polarized, and the other not P-Polarized.", "In practice the P-Polarized beam can be set to be incident on a Sample Surface at the SPR Resonance angle, and another Polarized beam, (eg.", "can be non-P-Polarized), at an angle perhaps closer to the Brewster angle.", "Said second Polarized beam can actually be P-Polarized if it is not incident on the sample surface at the SPR Resonant Angle.", "Both SPR and Conventional Ellipsometric analysis can then be conducted with the two Polarized beams being simultaneously, or sequentially applied.", "FIG. 2 c shows another approach to achieving multiple AOI's.", "A single Colimated (COL) beam can be focused onto a Sample (S), and said input can result in multiple Angles-of-Reflection (AOR's), each of which can be intercepted by different Dispersive Optics, (DO 1 ), (DO 2 ), (DO 3 ), (DO 4 ) and (DO 5 ) and a wavelengths spectrum from each directed into a separate Detectors (DET 1 ), (DET 2 ), (DET 3 ), (DET 4 ) AND (DET 5 ), respectively.", "Such an arrangement can be applied, via windows, to a Substrate Process Chamber (1V).", "FIG. 2 c also indicates a De-focusing means (DF) can be present to prevent focusing effects of the curved Window (AC 1 ) on a beam of electromagneic radiation passing therethrough.", "FIG. 2 d demonstrates that an alternative to providing windows (AC 1 ) (AC 2 ) through which electromagnetic radiation passes, as shown in FIG. 2 b and is necessary where the Substrate Process Chamber (1V) is evacuated, is to provide a purged Substrate Process Chamber (1V′).", "The FIG. 2 d embodiment shows Purge Gas (PG) being flowed through Tubes (T 1 ) (T 2 ) through which the incident beam (PPCLB) and reflected beam (EPCLB) electromagnetic beams are passed.", "The Tubes (T 1 ) and (T 2 ) can be secured to the Purged Substrate Process Chamber (1V′) by any means which minimizes escape of the Purging Gas (PG), while allowing change of the AOI and AOR.", "Use of Purged (1V′) rather than evacuated Substrate Process Chamber (1V) can be valuable in, for instance, Chemical Vapor Deposition (CVD) fabrication settings.", "The described invention can then be practiced in evacuated or purged Substrate Process Chamber (1V) environments.", "FIG. 2 e shows a (Cell) comprising a surface (SUR) of a sample stage element (STG) which is provided electromagnetic radiation EMI and EMI′ or EMI″ from a single source via divider means, (or separate sources could be used), and further indicates reflected beams EMO and EMO′ are directed to one or more Detector(s).", "The upper half of said (CELL) is a more conventional system applied in SPR research.", "It is to be understood that the electromagnetic beams EMI and EMI′ can comprise the same or different wavelength content.", "For instance, the same wavelength content can be present in EMI and EMI″ and different angles-of-incidence from above and below utilized, as indicated by EMI and dashed line EMI″.", "Different wavelength content can also be present in EMI and EMI″.", "Where different wavelength content is present, the beams EMI and EMI′ can be applied at the same angle-of-incidence, however, in this case the same wavelength content could be present and the purpose behind the configuration being solely to gain data pertaining to top and bottom aspects of a sample atop the surface of the sample stage element (STG).", "Normal angle of incidence electromagnetic beam EMI′″ is indicated as present as well, but no Polarizer or Analyzer is typically present in the EMI′″ beam locus.", "That is EMI′″ is a Transmission Intensity beam used to monitor sample absorbance.", "Note that optical fibers (F) and Couplers (COUP) can be utilized to guide incident and reflected electromagnetic beams.", "Also note that Analyzer(s) (A), Polarizers (P) and optional Compensator(s) (C 1 ) (C 2 ) along with the Detectors(s) indicated as shown in FIG. 1 , are assumed present in FIG. 2 e as functionally required.", "Note, where different wavelengths are to be provided in the multiple electromagnetic beams, utilizing a single source of electromagnetic radiation in combination with Couplers which including functional filtering means, is a possibility.", "In use fluid containing analyte (SSF) is flowed into (SI) and exits via (SO).", "Analyte deposits onto the Upper Surface between the “OR”", "rings and Surface Plasmon Resonance and and Conventional Elipsometry techniques can be applied in analysis as desxcribe above with respect to other systems.", "Calculated results are shown in FIGS. 3 a , 3 b , 4 a - 4 h and 5 a and 5 b , for Gold deposited onto BK-7 Glass.", "Said results are exemplary of how ellipsometric PSI and DELTA provide very high sensitivity to surface change at a Surface Plasmon Resonance (SPR) angle-of-incidence.", "FIGS. 3 a and 3 b demonstrate ellipsometric PSI and DELTA for BK7 Glass with 50 nm of Gold on its surface, as a function of Angle-of-Incidence, and at 680, 730 and 780 nm.", "Note in particular the very steep slope of the FIG. 3 b DELTA vs.", "AOI.", "FIGS. 4 a - 4 h demonstrate ellipsometric PSI and DELTA vs.", "Wavelength, at Angles-of-Incidence of 66, 70 and 74 degrees to a BK-7 Glass Prism upon which is deposited Gold.", "FIGS. 4 a and 4 b show ellipsometric PSI and DELTA for the case where 100 nm of Gold is deposited onto the investigated surface, FIGS. 4 c and 4 d show the results where 80 nm of Gold is deposited, FIGS. 4 e and 4 f show the case where 50 nm of Gold are present and FIGS. 4 g and 4 h show the results for the case where 40 nm of Gold is present.", "Note in FIG. 4 f the very steep slope in DELTA for the 66 and 70 Degree AOI's, which is not present in the other, (ie.", "4 b , 4 d and 4 h DELTA plots).", "Where results like shown in FIG. 4 f are present the ellipsometric DELTA provides extremely high sensitivity to change in surface properties of a sample.", "However, FIGS. 4 b , 4 d and 4 h show that the steep slope in ellipsometric DELTA is not always observed.", "FIGS. 4 a , 4 c , 4 e and 4 g show that reasonable sensitivity in ellipsometric PSI is present for all thicknesses of Gold.", "FIGS. 5 a and 5 b show expanded forms of FIGS. 4 e and 4 f. It should be appreciated that the disclosed invention can be applied to fabrication of thin films via deposition of material onto, or etching material from a substrate, as well as in monitoring analyte material which deposits onto a stage from an analyte containing fluid, (eg.", "liquid), sample.", "The very high sensitivity of ellipsometric PSI and/or DELTA at an SPR condition enhances the capability of ellipsometry to detect very thin layers of material deposited onto or removed from a substrate.", "It is also disclosed that the described methodology can be applied to samples after they have been fabricated.", "The terminology “Plasmon”", "is to be interpreted sufficiently broadly to include “Polaritons.”", "It is also conceived that the extra data provided by plasmons or polaritrons could serve to break correlation between thickness and refractive index, which correlation is inherrant in conventional single sample analysis ellipsometry.", "Having hereby disclosed the subject matter of the present invention, it should be obvious that many modifications, substitutions, and variations of the present invention are possible in view of the teachings.", "It is therefore to be understood that the invention may be practiced other than as specifically described, and should be limited in its breadth and scope only by the Claims." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rocking fulcrum member and, more particularly, to a crisscross-spring-type rocking fulcrum member used in a lever-type detector or the like. 2. Description of the Related Art In lever-type detectors or the like, a finger arm having a contactor attached to its tip is supported on a rocking fulcrum so as to be able to seesaw. The detector detects the amount of movement of the finger arm when the contactor is in contact with a work. Examples of rocking fulcrum members used in such detectors are an elastic fulcrum such as shown in FIG. 7C , an L-shaped spring fulcrum such as shown in FIG. 7B , a bearing (not shown) and crisscross spring fulcrums such as shown in FIG. 7A . Elastic fulcrums are capable of operating with accuracy but can be used only in a case where the measurement range is narrow because they have only restricted swing angles. L-shaped spring fulcrums are low-priced and are being widely used but have a drawback in that the fulcrum center is shifted with a swinging movement and cannot be suitably used as a precise fulcrum member. Bearing fulcrums can have any swing angle but need periodical replacement because their accuracy is reduced due to wear. Crisscross spring fulcrums include those formed by disposing two plate springs so that the plate springs cross each other as shown on the left-hand side of FIG. 7A , and those integrally formed by being cut by wire cutting as shown on the right-hand side of FIG. 7A . The latter have sufficient rigidity and high accuracy during repeated use and can therefore be suitably used as a precise fulcrum. A crisscross spring fulcrum such as shown on the left-hand side of FIG. 7A is fixed by screwing opposite ends of the two plate springs to members or by welding the opposite ends to the members. A method of die-casting a crisscross spring base member and embedding the opposite ends of the two plate springs in the crisscross spring base member at the time of casting is also used (see, for example, WO 98/20297 pamphlet). A crisscross spring fulcrum having two plate springs welded to grooves in a cylindrical housing has also been proposed (see, for example, U.S. Pat. No. 3,807,029). In assembly of the above-described crisscross spring fulcrum member fixed by screwing opposite ends of the two plate springs to members has problems that a considerably long time is required for assembly and variations in spring characteristic occur due to assembly errors. The crisscross spring fulcrum having two plate springs embedded in a crisscross spring base member by die casting as described in WO 98/20297 pamphlet and the crisscross spring fulcrum having two plate springs fixed to a base member by welding as described in U.S. Pat. No. 3,807,029 have a problem that a considerably long time is required for fabricating and the assembly and manufacturing costs are high and another problem that the plate springs are heated at a high temperature at the time of welding or die casting to degrade the spring characteristic. The crisscross spring fulcrum integrally formed by cutting using wire cutting electrodischarge machining also has a problem that a considerably long time is required for fabricating and the manufacturing cost is high and another problem that the characteristic of the spring degrades with time due to microcracks caused by machining. SUMMARY OF THE INVENTION In view of the above-described circumstances, an object of the present invention is to provide a rocking fulcrum member having a crisscross spring fulcrum, capable of being manufactured at a low cost with reduced variations in the spring characteristic, and capable of being easily assembled. To achieve the above-described object, according to a first aspect of the present invention, there is provided a rocking fulcrum member, comprising: a first elastic plate portion and a second elastic plate portion placed on planes intersecting each other to form a crisscross spring, wherein each of the first elastic plate portion and the second elastic plate portion has extensions from its one end and the other end in its longitudinal direction; the extension from the one end of the first elastic plate portion is bent at an acute angle from the first elastic plate portion, while the extension from the other end of the first elastic plate portion is bent at an obtuse angle from the first elastic plate portion; the extension from the one end of the second elastic plate portion is bent at an obtuse angle from the second elastic plate portion, while the extension from the other end of the second elastic plate portion is bent at an acute angle from the second elastic plate portion; the extension from the one end of the first elastic plate portion and the extension from the one end of the second elastic plate portion are formed as one continuous member on one plane; the extension from the other end of the first elastic plate portion and the extension from the other end of the second elastic plate portion are formed as one continuous member on one plane; and the first elastic plate portion, the extension from the one end of the first elastic plate portion, the extension from the other end of the first elastic plate portion, the second elastic plate portion, the extension from the one end of the second elastic plate portion and the extension from the other end of the second elastic plate portion are a continuous member formed by fabricating one elastic member in the form of a plate. In the first aspect of the present invention, it is preferable that a width of the first elastic plate portion and a width of the second elastic plate portion should be equal to each other. To achieve the above-described object, according to a second aspect of the present invention, there is provided a rocking fulcrum member, comprising: a first elastic plate portion, a second elastic plate portion and a third elastic plate portion, the first elastic plate portion and the third elastic plate portion being placed parallel to each other on one plane, the second elastic plate portion being placed between the first elastic plate portion and the third elastic plate portion, the first elastic plate portion, the third elastic plate portion and the second elastic plate portion being placed on planes intersecting each other to form a crisscross spring, wherein each of the first elastic plate portion, the second elastic plate portion and the third elastic plate portion has extensions from its one end and the other end in its longitudinal direction; the extension from the one end of the first elastic plate portion is bent at an acute angle from the first elastic plate portion, while the extension from the other end of the first elastic plate portion is bent at an obtuse angle from the first elastic plate portion; the extension from the one end of the second elastic plate portion is bent at an obtuse angle from the second elastic plate portion, while the extension from the other end of the second elastic plate portion is bent at an acute angle from the second elastic plate portion; the extension from the one end of the third elastic plate portion is bent at an acute angle from the third elastic plate portion, while the extension from the other end of the third elastic plate portion is bent at an obtuse angle from the third elastic plate portion; the extension from the one end of the first elastic plate portion, the extension from the one end of the second elastic plate portion and the extension from the one end of the third elastic plate portion are formed as one continuous member on one plane; the extension from the other end of the first elastic plate portion, the extension from the other end of the second elastic plate portion and the extension from the other end of the third elastic plate portion are formed as one continuous member on one plane; and the first elastic plate portion, the extension from the one end of the first elastic plate portion, the extension from the other end of the first elastic plate portion, the second elastic plate portion, the extension from the one end of the second elastic plate portion, the extension from the other end of the second elastic plate portion, the third elastic plate portion, the extension from the one end of the third elastic plate portion and the extension from the other end of the third elastic plate portion are a continuous member formed by fabricating one elastic member in the form of a plate. In the second aspect of the present invention, it is preferable that sum of a width of the first elastic plate portion and a width of the third elastic plate portion should be equal to a width of the second elastic plate portion. In the first or the second aspect of the present invention, it is preferable that an attachment hole for attachment of a member should be formed in each of the continuous member on one plane in which the extension from the one end of each elastic plate portion is formed and the continuous member on one plane in which the extension from the other end of each elastic plate portion is formed. According to the present invention, the crisscross fulcrum is formed as a continuous member by fabricating one elastic member in the form of a plate. Therefore, the rocking fulcrum member can be obtained as a precise fulcrum member at a low cost with reduced variations in the spring characteristic and can be easily assembled. In the first or the second aspect of the present invention, it is preferable that a heat treatment should be performed on the crisscross spring formed by fabricating the one elastic member in the form of a plate. By the heat treatment performed after fabricating for forming the crisscross spring, the spring characteristic is improved. As described above, the crisscross fulcrum in the rocking fulcrum member of the present invention is formed as a continuous member by fabricating one elastic member in the form of a plate and, therefore, the rocking fulcrum member can be obtained as a precise fulcrum member at a low cost with reduced variations in the spring characteristic and can be easily assembled. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a rocking fulcrum member according to an embodiment of the present invention; FIG. 2 is a side view of the rocking fulcrum member according to the embodiment of the present invention; FIG. 3 is a plan view of the rocking fulcrum member before forming; FIG. 4 is a perspective view of an example of a modification of the embodiment; FIG. 5 is a plan view of the rocking fulcrum member in the modification of the embodiment before forming; FIG. 6 is a sectional side view of an example of an application of the rocking fulcrum member of the present invention; and FIGS. 7A to 7C are perspective views of conventional rocking fulcrum members. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a rocking fulcrum member in accordance with the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same portions or components are indicated by the same reference numerals or symbols. FIG. 1 is a perspective view of an embodiment of a rocking fulcrum member in accordance with the present invention, and FIG. 2 is a side view of the embodiment. As shown in FIGS. 1 and 2 , the rocking fulcrum member 10 has a first elastic plate portion 10 A and a second elastic plate portion 10 B. The surfaces of the first elastic plate portion 10 A and the second elastic plate portion 10 B cross each other at right angles to form a crisscross spring 11 . An extension 10 C from one end of the first elastic plate portion 10 A is bent at 45° from the first elastic plate portion 10 A, while an extension 10 D from the other end of the first elastic plate portion 10 A is bent at 135° from the first elastic plate portion 10 A. An extension 10 E from one end of the second elastic plate portion 10 B is bent at 135° from the second elastic plate portion 10 B, while an extension 10 F from the other end of the second elastic plate portion 10 B is bent at 45° from the second elastic plate portion 10 B. The extension 10 C from one end of the first elastic plate portion and the extension 10 E from one end of the second elastic plate portion are formed integrally with each other to form one L-shaped flat plate, and the extension 10 D from the other end of the first elastic plate portion and the extension 10 F from the other end of the second elastic plate portion are also formed integrally with each other to form one L-shaped flat plate. Three attachment holes 10 G for attachment of a member are formed in each L-shaped flat plate. In the rocking fulcrum member 10 having the above-described structure, the L-shaped flat plate portions are parallel to each other in a no-load condition. When a force is applied to the L-shaped flat plate portions in such a direction that the L-shaped flat plate portions are brought closer to each other or moved away from each other, rocking on the crisscross fulcrum formed by the first elastic plate portion 10 A and the second elastic plate portion 10 B is caused. The rocking fulcrum member 10 is integrally formed into a state shown in FIGS. 1 and 2 from one elastic plate member 50 shown in FIG. 3 . A large-size elastic plate member is first punched with a punching press to form the elastic plate member 50 , six attachment holes 10 G and a central slit 50 A, and the elastic plate member 50 is thereafter press-formed so as to be bent through predetermined angles at positions indicated by dotted lines in FIG. 3 . A heat treatment is performed on the formed member to improve the spring characteristic. The width L 1 of the first elastic plate portion and the width L 2 of the second elastic plate portion are equal to each other and the precise crisscross spring fulcrum is formed in a torsion-free condition. FIG. 4 is a perspective view showing an example of a modification of the embodiment of the rocking fulcrum member in accordance with the present invention. A rocking fulcrum member 20 has a first elastic plate portion 20 A, a second elastic plate portion 20 B and a third elastic plate portion 20 H. The first elastic plate portion 20 A and the third elastic plate portion 20 H are placed parallel to each other with a certain spacing provided therebetween. The second elastic plate portion 20 B is placed between the first elastic plate portion 20 A and the third elastic plate portion 20 H. The surfaces of the first elastic plate portion 20 A, the third elastic plate portion 20 H and the second elastic plate portion 20 B cross each other at right angles to form a crisscross spring 21 . An extension 20 C from one end of the first elastic plate portion 20 A is bent at 45° from the first elastic plate portion 20 A, while an extension 20 D from the other end of the first elastic plate portion 20 A is bent at 135° from the first elastic plate portion 20 A. An extension 20 E from one end of the second elastic plate portion 20 B is bent at 135° from the second elastic plate portion 20 B, while an extension 20 F from the other end of the second elastic plate portion 20 B is bent at 45° from the second elastic plate portion 20 B. Further, an extension 20 J from one end of the third elastic plate portion 20 H is bent at 45° from the third elastic plate portion 20 H, while an extension 20 K (shown in FIG. 5 referred to below) from the other end of the third elastic plate portion 20 H is bent at 135° from the third elastic plate portion 20 H. The extension 20 C from one end of the first elastic plate portion, the extension 20 E from one end of the second elastic plate portion and the extension 20 J from one end of the third elastic plate portion are formed integrally with each other to form one generally concave flat plate, and the extension 20 D from the other end of the first elastic plate portion, the extension 20 F from the other end of the second elastic plate portion and the extension 20 K from the third elastic plate portion are also formed integrally with each other to form one generally convex flat plate. Four attachment holes 20 G for attachment of a member in the concave flat plate, and three attachment holes 20 G for attachment of a member in the convex flat plate are formed. In the rocking fulcrum member 20 having the above-described structure, the generally concave flat plate portions and the generally convex flat plate portions are parallel to each other in a no-load condition, as are the corresponding portions of the above-described rocking fulcrum member 10 . When a force is applied to the generally concave flat plate portions in such a direction that the generally convex flat plate portions are brought closer to each other or moved away from each other, rocking on the crisscross fulcrum formed by the first elastic plate portion 20 A, the third elastic plate portion 20 H and the second elastic plate portion 20 B is caused. The rocking fulcrum member 20 is integrally formed into a state shown in FIG. 4 from one elastic plate member 60 shown in FIG. 5 , as is the above-described rocking fulcrum member 10 . A large-size elastic plate member is first punched with a punching press to form the elastic plate member 60 , seven attachment holes 20 G and two central slits 60 A, and the elastic plate member 60 is thereafter press-formed so as to be bent through predetermined angles at positions indicated by dotted lines in FIG. 5 . A heat treatment is performed on the formed member to improve the spring characteristic. The width L 3 of the first elastic plate portion and the width L 5 of the third elastic plate portion are equal to each other and the sum of the width L 3 of the first elastic plate portion and the width L 5 of the third elastic plate portion is equal to the width L 4 of the second elastic plate portion. The precise crisscross fulcrum is formed in a torsion-free condition. FIG. 6 shows an example of an application of the rocking fulcrum member 10 in accordance with the present invention to a rocking fulcrum for a measuring head 80 . In the measuring head 80 , one of the L-shaped flat plate portions of the rocking fulcrum member 10 is screwed to a measuring head body 81 by using the three attachment holes 10 G and an attachment plate 82 having three threaded holes, as shown in FIG. 6 . An arm member 83 is screwed to the other L-shaped flat plate portion of the rocking fulcrum member 10 by using another attachment plate 82 . A finger 84 is attached to a fore end of the arm member 83 . A contactor 85 is attached to a tip of the finger 84 . A core 86 of a differential transformer is attached to a rear end of the arm member 83 . A coil 87 of the differential transformer is attached to the measuring head body 81 . A compression coil spring 88 is provided between the measuring head body 81 and the arm member 83 to apply a measuring pressure to the contactor 85 . A stopper screw provided in the measuring head body 81 is used to set a rocking lower end of the arm member 83 . In the measuring head 80 having the above-described structure, the arm member 83 seesaws on the crisscross spring fulcrum formed by the rocking fulcrum member 10 . The amount of movement of the contactor 85 when the contactor 85 is in contact with a work is detected with the differential transformer, thus making an accurate measurement. The rocking fulcrum member 10 is a press-formed crisscross spring fulcrum member integrally formed as described above. Therefore, the rocking fulcrum member 10 can be manufactured at a low cost and easily mounted, are free from variations in crisscross spring fulcrum characteristic due to variations in the mounted state and can be suitably used as a precise rocking fulcrum. In the above-described embodiment, the crisscross spring in which the surfaces of the first elastic plate spring portion 10 A and the second elastic plate spring portion 10 B cross each other at right angles is formed. In the example of modification of the embodiment, the crisscross spring in which the surfaces of the first elastic plate spring portion 20 A, the third elastic plate spring portion 20 H and the second elastic plate spring portion 20 B cross each other at right angles is formed. However, the crossing angle between these portions in the arrangement of the present invention may be different from 90°.
The crisscross fulcrum according to the present invention is formed as a continuous member by fabricating one elastic member in the form of a plate. Therefore, the rocking fulcrum member can be obtained as a precise fulcrum member at a low cost with reduced variations in the spring characteristic and can be easily assembled. Additionally, in the present invention, it is preferable that a heat treatment should be performed on the crisscross spring formed by fabricating the one elastic member in the form of a plate. By the heat treatment performed after fabricating for forming the crisscross spring, the spring characteristic is improved.
Concisely explain the essential features and purpose of the concept presented in the passage.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to a rocking fulcrum member and, more particularly, to a crisscross-spring-type rocking fulcrum member used in a lever-type detector or the like.", "Description of the Related Art In lever-type detectors or the like, a finger arm having a contactor attached to its tip is supported on a rocking fulcrum so as to be able to seesaw.", "The detector detects the amount of movement of the finger arm when the contactor is in contact with a work.", "Examples of rocking fulcrum members used in such detectors are an elastic fulcrum such as shown in FIG. 7C , an L-shaped spring fulcrum such as shown in FIG. 7B , a bearing (not shown) and crisscross spring fulcrums such as shown in FIG. 7A .", "Elastic fulcrums are capable of operating with accuracy but can be used only in a case where the measurement range is narrow because they have only restricted swing angles.", "L-shaped spring fulcrums are low-priced and are being widely used but have a drawback in that the fulcrum center is shifted with a swinging movement and cannot be suitably used as a precise fulcrum member.", "Bearing fulcrums can have any swing angle but need periodical replacement because their accuracy is reduced due to wear.", "Crisscross spring fulcrums include those formed by disposing two plate springs so that the plate springs cross each other as shown on the left-hand side of FIG. 7A , and those integrally formed by being cut by wire cutting as shown on the right-hand side of FIG. 7A .", "The latter have sufficient rigidity and high accuracy during repeated use and can therefore be suitably used as a precise fulcrum.", "A crisscross spring fulcrum such as shown on the left-hand side of FIG. 7A is fixed by screwing opposite ends of the two plate springs to members or by welding the opposite ends to the members.", "A method of die-casting a crisscross spring base member and embedding the opposite ends of the two plate springs in the crisscross spring base member at the time of casting is also used (see, for example, WO 98/20297 pamphlet).", "A crisscross spring fulcrum having two plate springs welded to grooves in a cylindrical housing has also been proposed (see, for example, U.S. Pat. No. 3,807,029).", "In assembly of the above-described crisscross spring fulcrum member fixed by screwing opposite ends of the two plate springs to members has problems that a considerably long time is required for assembly and variations in spring characteristic occur due to assembly errors.", "The crisscross spring fulcrum having two plate springs embedded in a crisscross spring base member by die casting as described in WO 98/20297 pamphlet and the crisscross spring fulcrum having two plate springs fixed to a base member by welding as described in U.S. Pat. No. 3,807,029 have a problem that a considerably long time is required for fabricating and the assembly and manufacturing costs are high and another problem that the plate springs are heated at a high temperature at the time of welding or die casting to degrade the spring characteristic.", "The crisscross spring fulcrum integrally formed by cutting using wire cutting electrodischarge machining also has a problem that a considerably long time is required for fabricating and the manufacturing cost is high and another problem that the characteristic of the spring degrades with time due to microcracks caused by machining.", "SUMMARY OF THE INVENTION In view of the above-described circumstances, an object of the present invention is to provide a rocking fulcrum member having a crisscross spring fulcrum, capable of being manufactured at a low cost with reduced variations in the spring characteristic, and capable of being easily assembled.", "To achieve the above-described object, according to a first aspect of the present invention, there is provided a rocking fulcrum member, comprising: a first elastic plate portion and a second elastic plate portion placed on planes intersecting each other to form a crisscross spring, wherein each of the first elastic plate portion and the second elastic plate portion has extensions from its one end and the other end in its longitudinal direction;", "the extension from the one end of the first elastic plate portion is bent at an acute angle from the first elastic plate portion, while the extension from the other end of the first elastic plate portion is bent at an obtuse angle from the first elastic plate portion;", "the extension from the one end of the second elastic plate portion is bent at an obtuse angle from the second elastic plate portion, while the extension from the other end of the second elastic plate portion is bent at an acute angle from the second elastic plate portion;", "the extension from the one end of the first elastic plate portion and the extension from the one end of the second elastic plate portion are formed as one continuous member on one plane;", "the extension from the other end of the first elastic plate portion and the extension from the other end of the second elastic plate portion are formed as one continuous member on one plane;", "and the first elastic plate portion, the extension from the one end of the first elastic plate portion, the extension from the other end of the first elastic plate portion, the second elastic plate portion, the extension from the one end of the second elastic plate portion and the extension from the other end of the second elastic plate portion are a continuous member formed by fabricating one elastic member in the form of a plate.", "In the first aspect of the present invention, it is preferable that a width of the first elastic plate portion and a width of the second elastic plate portion should be equal to each other.", "To achieve the above-described object, according to a second aspect of the present invention, there is provided a rocking fulcrum member, comprising: a first elastic plate portion, a second elastic plate portion and a third elastic plate portion, the first elastic plate portion and the third elastic plate portion being placed parallel to each other on one plane, the second elastic plate portion being placed between the first elastic plate portion and the third elastic plate portion, the first elastic plate portion, the third elastic plate portion and the second elastic plate portion being placed on planes intersecting each other to form a crisscross spring, wherein each of the first elastic plate portion, the second elastic plate portion and the third elastic plate portion has extensions from its one end and the other end in its longitudinal direction;", "the extension from the one end of the first elastic plate portion is bent at an acute angle from the first elastic plate portion, while the extension from the other end of the first elastic plate portion is bent at an obtuse angle from the first elastic plate portion;", "the extension from the one end of the second elastic plate portion is bent at an obtuse angle from the second elastic plate portion, while the extension from the other end of the second elastic plate portion is bent at an acute angle from the second elastic plate portion;", "the extension from the one end of the third elastic plate portion is bent at an acute angle from the third elastic plate portion, while the extension from the other end of the third elastic plate portion is bent at an obtuse angle from the third elastic plate portion;", "the extension from the one end of the first elastic plate portion, the extension from the one end of the second elastic plate portion and the extension from the one end of the third elastic plate portion are formed as one continuous member on one plane;", "the extension from the other end of the first elastic plate portion, the extension from the other end of the second elastic plate portion and the extension from the other end of the third elastic plate portion are formed as one continuous member on one plane;", "and the first elastic plate portion, the extension from the one end of the first elastic plate portion, the extension from the other end of the first elastic plate portion, the second elastic plate portion, the extension from the one end of the second elastic plate portion, the extension from the other end of the second elastic plate portion, the third elastic plate portion, the extension from the one end of the third elastic plate portion and the extension from the other end of the third elastic plate portion are a continuous member formed by fabricating one elastic member in the form of a plate.", "In the second aspect of the present invention, it is preferable that sum of a width of the first elastic plate portion and a width of the third elastic plate portion should be equal to a width of the second elastic plate portion.", "In the first or the second aspect of the present invention, it is preferable that an attachment hole for attachment of a member should be formed in each of the continuous member on one plane in which the extension from the one end of each elastic plate portion is formed and the continuous member on one plane in which the extension from the other end of each elastic plate portion is formed.", "According to the present invention, the crisscross fulcrum is formed as a continuous member by fabricating one elastic member in the form of a plate.", "Therefore, the rocking fulcrum member can be obtained as a precise fulcrum member at a low cost with reduced variations in the spring characteristic and can be easily assembled.", "In the first or the second aspect of the present invention, it is preferable that a heat treatment should be performed on the crisscross spring formed by fabricating the one elastic member in the form of a plate.", "By the heat treatment performed after fabricating for forming the crisscross spring, the spring characteristic is improved.", "As described above, the crisscross fulcrum in the rocking fulcrum member of the present invention is formed as a continuous member by fabricating one elastic member in the form of a plate and, therefore, the rocking fulcrum member can be obtained as a precise fulcrum member at a low cost with reduced variations in the spring characteristic and can be easily assembled.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a rocking fulcrum member according to an embodiment of the present invention;", "FIG. 2 is a side view of the rocking fulcrum member according to the embodiment of the present invention;", "FIG. 3 is a plan view of the rocking fulcrum member before forming;", "FIG. 4 is a perspective view of an example of a modification of the embodiment;", "FIG. 5 is a plan view of the rocking fulcrum member in the modification of the embodiment before forming;", "FIG. 6 is a sectional side view of an example of an application of the rocking fulcrum member of the present invention;", "and FIGS. 7A to 7C are perspective views of conventional rocking fulcrum members.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a rocking fulcrum member in accordance with the present invention will be described in detail with reference to the accompanying drawings.", "In the drawings, the same portions or components are indicated by the same reference numerals or symbols.", "FIG. 1 is a perspective view of an embodiment of a rocking fulcrum member in accordance with the present invention, and FIG. 2 is a side view of the embodiment.", "As shown in FIGS. 1 and 2 , the rocking fulcrum member 10 has a first elastic plate portion 10 A and a second elastic plate portion 10 B. The surfaces of the first elastic plate portion 10 A and the second elastic plate portion 10 B cross each other at right angles to form a crisscross spring 11 .", "An extension 10 C from one end of the first elastic plate portion 10 A is bent at 45° from the first elastic plate portion 10 A, while an extension 10 D from the other end of the first elastic plate portion 10 A is bent at 135° from the first elastic plate portion 10 A. An extension 10 E from one end of the second elastic plate portion 10 B is bent at 135° from the second elastic plate portion 10 B, while an extension 10 F from the other end of the second elastic plate portion 10 B is bent at 45° from the second elastic plate portion 10 B. The extension 10 C from one end of the first elastic plate portion and the extension 10 E from one end of the second elastic plate portion are formed integrally with each other to form one L-shaped flat plate, and the extension 10 D from the other end of the first elastic plate portion and the extension 10 F from the other end of the second elastic plate portion are also formed integrally with each other to form one L-shaped flat plate.", "Three attachment holes 10 G for attachment of a member are formed in each L-shaped flat plate.", "In the rocking fulcrum member 10 having the above-described structure, the L-shaped flat plate portions are parallel to each other in a no-load condition.", "When a force is applied to the L-shaped flat plate portions in such a direction that the L-shaped flat plate portions are brought closer to each other or moved away from each other, rocking on the crisscross fulcrum formed by the first elastic plate portion 10 A and the second elastic plate portion 10 B is caused.", "The rocking fulcrum member 10 is integrally formed into a state shown in FIGS. 1 and 2 from one elastic plate member 50 shown in FIG. 3 .", "A large-size elastic plate member is first punched with a punching press to form the elastic plate member 50 , six attachment holes 10 G and a central slit 50 A, and the elastic plate member 50 is thereafter press-formed so as to be bent through predetermined angles at positions indicated by dotted lines in FIG. 3 .", "A heat treatment is performed on the formed member to improve the spring characteristic.", "The width L 1 of the first elastic plate portion and the width L 2 of the second elastic plate portion are equal to each other and the precise crisscross spring fulcrum is formed in a torsion-free condition.", "FIG. 4 is a perspective view showing an example of a modification of the embodiment of the rocking fulcrum member in accordance with the present invention.", "A rocking fulcrum member 20 has a first elastic plate portion 20 A, a second elastic plate portion 20 B and a third elastic plate portion 20 H. The first elastic plate portion 20 A and the third elastic plate portion 20 H are placed parallel to each other with a certain spacing provided therebetween.", "The second elastic plate portion 20 B is placed between the first elastic plate portion 20 A and the third elastic plate portion 20 H. The surfaces of the first elastic plate portion 20 A, the third elastic plate portion 20 H and the second elastic plate portion 20 B cross each other at right angles to form a crisscross spring 21 .", "An extension 20 C from one end of the first elastic plate portion 20 A is bent at 45° from the first elastic plate portion 20 A, while an extension 20 D from the other end of the first elastic plate portion 20 A is bent at 135° from the first elastic plate portion 20 A. An extension 20 E from one end of the second elastic plate portion 20 B is bent at 135° from the second elastic plate portion 20 B, while an extension 20 F from the other end of the second elastic plate portion 20 B is bent at 45° from the second elastic plate portion 20 B. Further, an extension 20 J from one end of the third elastic plate portion 20 H is bent at 45° from the third elastic plate portion 20 H, while an extension 20 K (shown in FIG. 5 referred to below) from the other end of the third elastic plate portion 20 H is bent at 135° from the third elastic plate portion 20 H. The extension 20 C from one end of the first elastic plate portion, the extension 20 E from one end of the second elastic plate portion and the extension 20 J from one end of the third elastic plate portion are formed integrally with each other to form one generally concave flat plate, and the extension 20 D from the other end of the first elastic plate portion, the extension 20 F from the other end of the second elastic plate portion and the extension 20 K from the third elastic plate portion are also formed integrally with each other to form one generally convex flat plate.", "Four attachment holes 20 G for attachment of a member in the concave flat plate, and three attachment holes 20 G for attachment of a member in the convex flat plate are formed.", "In the rocking fulcrum member 20 having the above-described structure, the generally concave flat plate portions and the generally convex flat plate portions are parallel to each other in a no-load condition, as are the corresponding portions of the above-described rocking fulcrum member 10 .", "When a force is applied to the generally concave flat plate portions in such a direction that the generally convex flat plate portions are brought closer to each other or moved away from each other, rocking on the crisscross fulcrum formed by the first elastic plate portion 20 A, the third elastic plate portion 20 H and the second elastic plate portion 20 B is caused.", "The rocking fulcrum member 20 is integrally formed into a state shown in FIG. 4 from one elastic plate member 60 shown in FIG. 5 , as is the above-described rocking fulcrum member 10 .", "A large-size elastic plate member is first punched with a punching press to form the elastic plate member 60 , seven attachment holes 20 G and two central slits 60 A, and the elastic plate member 60 is thereafter press-formed so as to be bent through predetermined angles at positions indicated by dotted lines in FIG. 5 .", "A heat treatment is performed on the formed member to improve the spring characteristic.", "The width L 3 of the first elastic plate portion and the width L 5 of the third elastic plate portion are equal to each other and the sum of the width L 3 of the first elastic plate portion and the width L 5 of the third elastic plate portion is equal to the width L 4 of the second elastic plate portion.", "The precise crisscross fulcrum is formed in a torsion-free condition.", "FIG. 6 shows an example of an application of the rocking fulcrum member 10 in accordance with the present invention to a rocking fulcrum for a measuring head 80 .", "In the measuring head 80 , one of the L-shaped flat plate portions of the rocking fulcrum member 10 is screwed to a measuring head body 81 by using the three attachment holes 10 G and an attachment plate 82 having three threaded holes, as shown in FIG. 6 .", "An arm member 83 is screwed to the other L-shaped flat plate portion of the rocking fulcrum member 10 by using another attachment plate 82 .", "A finger 84 is attached to a fore end of the arm member 83 .", "A contactor 85 is attached to a tip of the finger 84 .", "A core 86 of a differential transformer is attached to a rear end of the arm member 83 .", "A coil 87 of the differential transformer is attached to the measuring head body 81 .", "A compression coil spring 88 is provided between the measuring head body 81 and the arm member 83 to apply a measuring pressure to the contactor 85 .", "A stopper screw provided in the measuring head body 81 is used to set a rocking lower end of the arm member 83 .", "In the measuring head 80 having the above-described structure, the arm member 83 seesaws on the crisscross spring fulcrum formed by the rocking fulcrum member 10 .", "The amount of movement of the contactor 85 when the contactor 85 is in contact with a work is detected with the differential transformer, thus making an accurate measurement.", "The rocking fulcrum member 10 is a press-formed crisscross spring fulcrum member integrally formed as described above.", "Therefore, the rocking fulcrum member 10 can be manufactured at a low cost and easily mounted, are free from variations in crisscross spring fulcrum characteristic due to variations in the mounted state and can be suitably used as a precise rocking fulcrum.", "In the above-described embodiment, the crisscross spring in which the surfaces of the first elastic plate spring portion 10 A and the second elastic plate spring portion 10 B cross each other at right angles is formed.", "In the example of modification of the embodiment, the crisscross spring in which the surfaces of the first elastic plate spring portion 20 A, the third elastic plate spring portion 20 H and the second elastic plate spring portion 20 B cross each other at right angles is formed.", "However, the crossing angle between these portions in the arrangement of the present invention may be different from 90°." ]
CROSS REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of co-pending application Ser. No. 61/583,971, filed Jan. 6, 2012, entitled INTERACTIVE APPARATUS. [0002] The present invention relates to an interactive personal robotic apparatus and, more particularly, to an interactive robotic apparatus interfaced with a personal computer. BACKGROUND [0003] Various personal robots are well known. Personal robots that display pre-determined movements are also known. Conventional personal robots are typically battery powered and move in predictable ways, and do not positively interact with the user or exhibit a personality. This limits their use and utility. SUMMARY [0004] The present invention provides a robotic apparatus that interacts with a user and a personal computer (PC). The interactive apparatus receives inputs from the user and from the PC and reacts and interacts. The interactive apparatus includes a USB interface with the PC to receive power and data such as key strokes, key combinations, email notifications, and web cam events, for example. The interactive apparatus also includes microphones and a phototransistor to detect sounds and movement. The interactive apparatus includes an eye assembly attached to a body and leg, which is responsive to inputs and interactions with the user and PC. DESCRIPTION OF THE DRAWINGS [0005] FIG. 1 is a front elevational view of an interactive apparatus of the present invention. [0006] FIG. 2 is a right side view of the interactive apparatus of FIG. 1 . [0007] FIG. 3 is a left side view of the interactive apparatus of FIG. 1 . [0008] FIG. 4 is a back view of the interactive apparatus of FIG. 1 . [0009] FIG. 5 is a top view of the interactive apparatus of FIG. 1 . [0010] FIG. 6 is a bottom view of the interactive apparatus of FIG. 1 . [0011] FIG. 7 is a perspective view of the interactive apparatus of FIG. 1 . [0012] FIG. 8 is a partial exploded perspective view of the interactive apparatus of FIG. 1 . [0013] FIG. 9 is an exploded perspective view from right to left of the interactive apparatus of FIG. 1 . [0014] FIG. 9A is an enlarged exploded perspective view of the eye assembly of FIG. 9 . [0015] FIG. 9B is an enlarged exploded perspective view of the body assembly of FIG. 9 . [0016] FIG. 9C is an enlarged exploded perspective view of the leg assembly of FIG. 9 . [0017] FIG. 9D is an enlarged exploded perspective view of the base assembly of FIG. 9 . [0018] FIG. 9E is an enlarged exploded perspective view of the foot assembly of FIG. 9 . [0019] FIG. 10 is a functional block diagram of the control components of the interactive apparatus. DETAILED DESCRIPTION [0020] As required, detailed embodiments of the present invention are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for the claims and/or as a representative basis for teaching one skilled in the art to variously employ the present invention. [0021] Moreover, except where otherwise expressly indicated, all numerical quantities in this description and in the claims are to be understood as modified by the word “about” in describing the broader scope of this invention. Practice within the numerical limits stated is generally preferred. Also, unless expressly stated to the contrary, the description of a group or class of materials as suitable or preferred for a given purpose in connection with the invention implies that mixtures or combinations of any two or more members of the group or class may be equally suitable or preferred. [0022] Referring to the figures, an interactive apparatus of the present invention is generally indicated by reference numeral 20 . The interactive apparatus 20 includes a base assembly 22 , a foot assembly 24 , which may be circular as shown, a leg 26 , a knee 28 , a body assembly 30 , an eye assembly 32 and an eyelid 34 . The eye assembly 32 is rotationally coupled to the body assembly 30 , which may be pivotably coupled to the leg assembly 26 at the knee 28 thereby permitting movements about a rotational axis 29 . The leg assembly 26 is pivotably coupled to the foot assembly 24 for rotation about a rotational axis 31 . [0023] Referring to FIGS. 8 and 9 , the eye assembly 32 includes a lens 36 and a lens mounting plate 38 fastened to mounting posts 40 secured to a back or cap 42 of the eye assembly 32 . An eyelid drive motor 44 is coupled to eyelid actuation gears 46 , which are coupled to the eyelid 34 and mounted to the back of the eye 42 . An eyelid position sensor 48 coupled to the eyelid drive shaft 50 measures the rotational position of the eyelid 34 around an eyelid axis of rotation 52 . A lower eye cover 54 is fastened to the back of the eye 42 and covers the lower edge of the lens 36 . The lower eye cover 54 is fastened to a pivot plate 56 , which is rotationally coupled to the body assembly 30 , to connect the eye assembly 32 to the body assembly 30 . [0024] The body assembly 30 includes a housing 58 with left 60 and right 62 halves, which are fastened together. An eye assembly drive motor 64 is coupled to an eye assembly gear box 66 and mounted to the left half 60 of the housing 58 . An eye assembly drive shaft 68 is coupled to the pivot plate 56 to pivot the eye assembly 32 back and forth. An eye assembly position sensor 70 is also coupled to the eye assembly drive shaft 68 and measures the rotational position of the eye assembly 32 about an axis of rotation 72 . [0025] The body assembly 30 is pivotally coupled to the leg assembly 26 at the knee 28 . The leg assembly 26 includes a leg housing 74 with left 76 and right 78 halves fastened together. A body assembly drive motor 80 is mounted in the left half 76 of the leg housing 74 . A spindle gear 82 coupled to a drive shaft 84 of the body assembly drive motor 80 engages a crown gear 86 . A body assembly drive shaft 88 coupled to the crown gear 86 passes through an aperture 90 in an upper end 92 of the right half 78 of the leg assembly housing 74 and engages a slot 94 in a lower end 96 of the right half 62 of the body assembly housing 58 . [0026] The crown gear 86 is also coupled to spindle gears 98 , which are coupled to a body assembly position sensor 100 and measures the rotational position of the body assembly 30 . [0027] The leg assembly 26 is pivotally coupled to the foot assembly 24 at a lower end 102 of the leg assembly housing 74 . A leg assembly drive motor 104 is mounted in a foot gear box 106 . A worm gear 108 coupled to a drive shaft 110 of the leg assembly drive motor 104 engages leg assembly drive gears 112 , which are coupled to a leg assembly drive shaft 114 . The drive shaft 114 passes through an aperture 116 in the foot gear box 106 to engage a slotted aperture 120 in the lower end 102 of the leg assembly 26 . The foot gear box 106 is mounted to a foot pad 118 . The lower end 102 of the leg assembly 26 is pivotally coupled to the foot pad 118 by left 122 and right 124 bearings, which engage slots 126 and 128 , respectively. The foot assembly 24 also includes a USB port 130 , a head phone jack 132 , and a photo transistor 134 . A base plate 119 covers the bottom of the foot pad 118 . [0028] The base assembly 22 includes a shell 135 , a pair of speakers 136 and 138 , speaker mounts 137 and 139 mounted behind speaker grills 140 and 142 , respectively. Additionally, left 144 and right 146 microphones are mounted on each side of the base 22 . [0029] Referring to FIGS. 10 and 8 - 9 , a control circuit, generally indicated by reference numeral 150 , is mounted to the foot assembly 24 . The control circuit 150 includes a microprocessor control unit (“MCU”) 152 and an internal memory 154 . The MCU 152 receives power and other inputs from a personal computer 156 connected via a USB cable 158 to the USB port 130 . The MCU 152 receives input from the photo transducer 134 , microphones 144 and 146 , and from the servos 44 , 64 , 80 and 104 , as well as position sensors 48 , 70 and 100 . Input from the left 144 and right 146 microphones permit the MCU 152 to determine the direction/position of the received sound to actuate the servos in response thereto. Input from the photo transistor 134 permits the MCU 152 to detect movement to wake up the apparatus 20 , for example, in response to the presence of a user. A webcam 161 may be mounted to lens mounting plate 38 behind lens 36 and coupled to MCU 152 . [0030] The interactive apparatus 20 receives user interactions or PC 156 via the USB port 130 . Based on PC outputs or external inputs, the interactive apparatus 20 may perform motion animations as well as audio output and activation of an LED 160 for a visual output. LED 160 may be a single LED or multiple LEDs such as a RGB LED. Activities which may trigger interactive apparatus 20 responses may include mouse cursor movements, keyboard inputs, email events, PC audio output, user movements, activation of a webcam, or voice prompts, for example. [0031] When the PC 156 is shut down, the interactive apparatus 20 may shut down as well. The MCU 152 sends a signal to the eyelid servo 44 to rotate the eyelid 34 to a closed position covering the lens 36 . The MCU 152 sends a signal to the body actuator 80 and the leg actuator 104 to rotate forward and back, respectively, to move the interactive apparatus 20 into a folded “resting” or “sleeping” position. When the PC 156 is in a stand by or power save mode, USB power is still available to the MCU 152 . The MCU 152 may send signals to the servos to perform “rest” or “daydream” animations, such as a slow turn of the eye 32 , movement of the body 30 and leg 26 and slow blink of the eyelid 34 , for example. While in a “rest” mode, the interactive apparatus 20 may make responsive animations to a loud sound or movement detected by the photo transistor 134 , for example. [0032] When the PC 156 is turned on and power from the USB 158 is applied to the MCU 152 , the interactive apparatus 20 may exhibit a wake up animation, such as stretching by extending the body 30 and leg 26 , and blinking slowly and widely, by slowly activating the eyelid servo 44 and slowly looking around by actuating the eye assembly servo 64 , making an associated “wake up” sound, and activating the LED 160 . [0033] When input is detected by the MCU 152 from the USB port 158 , the interactive apparatus 20 may exhibit various “companion” mode animations and responses. For example, when an email is received, the interactive apparatus may perform an alert animation such as moving up and down quickly by simultaneously actuating the leg servo 104 and body servo 80 . [0034] When certain predefined or programmed words are typed via the keyboard and received by the MCU 152 via the USB port 158 , specific animations, activation of the speakers 136 and 138 to output associated sounds, and/or activation of the LED 160 may be performed. [0035] For example, when a user has typed words such as “good,” alive,” “native,” “social,” “lucky,” “excellent,” “wonderful,” “perfect,” “right,” “correct,” “classy” or “elegant,” a “good” animation may be played, such as moving the body 30 quickly forward twice. [0036] When the user has typed words such as “bad,” “abuse,” “hate,” “rage,” “cheap,” “dangerous,” “serious,” “risky,” “hazardous” or “unsafe,” a “bad” animation may be played, such as closing the eye 32 , and moving the body 30 forward and down to a low position, for example. [0037] When the user has typed words such as “happy,” “joyful,” delighted,” “merry,” “joyous,” “glad,” and “pleased,” a “happy” animation such as moving the body 30 quickly forward and backward, and up and down, may be played. [0038] When the user has typed words such as “sad,” “alone,” abject,” “grief,” “hopeless,” “sorry,” “single,” “pity,” “poor,” “joyless,” “woeful,” “depressed,” “tearful” or “sorrowful,” for example, a “sad” animation may be played such as bending the body 30 and leg 26 backward slowly and then bend forward quickly, and repeating one or more times. [0039] When the user has typed a word such as “angry,” “rage,” “paddy,” “mad,” “wrathful” or “raging,” an “angry” animation such as bending the body 30 and leg 26 backward slowly and then forward quickly, may be played, and repeated one or more times. [0040] When the user has typed a word such as “excited,” “heartfelt,” “cordial,” “heated” or “crazy,” an “excited” animation such as turning the eye 32 quickly and then blinking, may be played. [0041] When the user has typed a word “dislike,” “hated,” “disdain,” despised,” “loathe” or “scornful,” a “dislike” animation by be played such as bending the body 30 backward, opening the eye 32 open slightly and then turning the eye 32 very quickly, for example. [0042] When the user has typed a word such as “liked,” “loved,” “nuts,” “favor” or “enjoy,” a “liked” animation may be played such as turning and blinking the eye 32 quickly. [0043] When the user has typed a word such as “sweet,” “naughty,” “lovely,” “cute,” “likeable” or “smart,” a “sweet” animation may be played such as turning the eye 32 left slowly and then closing the eye 32 very slowly, for example. [0044] When the user has typed a word such as “sure,” “obvious,” “resolved,” “trusty,” “yes” or “reliable,” a “sure” animation may be played such as moving the body 30 left and upright and then blinking the eye 32 twice slowly, for example. [0045] When the user has typed a word such as “negative” or “passive,” a “negative” animation may be played such as bending the body 30 backward, opening the eye 32 slightly and then turning the eye 32 slowly, for example. [0046] When the user has typed a word such as “hungry,” a “hungry” animation may be played such as turning the eye 32 left and right slowly and then blinking. [0047] When the user has typed a word such as “eat,” an “eat” animation may be played such as half opening the eye 32 and then blinking very slowly, for example. [0048] When the user has typed a word such as “scared,” “agape,” “horror,” “panic,” “fearful,” “awful,” “terrible,” “awesome,” “terrified” or “gazed,” a “scared” animation may be played such as closing the eye 32 , moving the leg 26 and body 30 to a low position. [0049] When the user has typed a word such as “laugh” or “absurd,” a “laugh” animation may be played such as moving the body 30 forward and backward in small increments of movement, for example. [0050] When the user has typed a word such as “cry,” “afraid,” shout” or “yell,” a “cry” animation may be played such as bending the body 30 forward, turning the eye 32 left and right and then half opening the eye 32 . [0051] When the user has typed a word such as “alert,” “suspicious,” “doubted” or “puzzled,” an “alert” animation may be played such as turning the eye left and right quickly and then stopping at the left side, for example. [0052] When the user has typed a word such as “sick,” “old,” “lousy,” “diseased” or “unsound,” a “sick” animation may be played such as turning the eye 32 left and right very quickly and then opening the eye 32 slightly, for example. [0053] When the user has typed a word such as “nasty,” “messy” or “rude,” a “nasty” animation may be played such as closing the eye 32 and then turning the eye 32 left and right very quickly, for example. [0054] When user has typed a word such as “easy,” “pure,” “relaxed,” “refined,” “cozy,” “easeful,” “comfortable” or “homelike,” an “easy” animation may be played such as bending the body 30 backward and then closing the eye 32 slowly. [0055] When the user has typed a word such as “curious” or “question,” a “curious” animation may be played such as turning the eye 32 to the left, to the right and then back to the center again. [0056] When the user has typed a word such as “kind,” “nice,” “affable,” “merciful,” “friendly,” “softhearted,” “brotherly” or “genial,” a “kind” animation may be played such as bending the body backward, and turning the eye 32 left and right and then blinking, for example. [0057] When the user has typed a word such as “sexy” or “fair,” a “sexy” animation may be played such as turning the eye 32 right or left and then blinking, for example. [0058] When the user has typed a word such as “manly,” a “manly” animation may be played such as turning the eye 32 left and right slowly and then return to the center position very quickly, for example. [0059] When the user has typed a word such as “shy” or “ashamed,” a “shy” animation may be played such bending the body 30 and leg 26 forward completely, and blinking the eye 32 slowly. [0060] When the user has typed a word such as “dog,” a dog-like animation may be played such as bending the body 30 and leg 26 backward and then bending the body 30 forward and backward in sync with a dog sound generated by the MCU 152 and output on speakers 136 and 138 . [0061] When the user has typed a word such as “pig,” a pig-like animation may be played such as bending the body 30 and leg 26 backward, and closing the eye 32 slowly, and then bending the body 30 forward and backward in sync with a pig sound generated by the MCU 152 and output on speakers 136 and 138 . [0062] When the user has typed a word such as “cat,” a cat-like animation may be played such as bending the body 30 and leg 26 backward, then bending the body 30 forward slightly, and then turning the eye 32 left and right, for example. [0063] When a web cam is being used, the MCU 152 will actuate the eye assembly servo 64 to turn to the direction of the speaker's voice using input from the microphones 144 and 146 , for example. [0064] When music is detected by the MCU 152 , the MCU 152 will actuate servos 44 , 66 , 80 and 104 to perform a dancing animation in sync with the beat of the music, for example. Other sound input from the microphones 144 and 146 as detected by the MCU 152 may produce additional animations. One animation is body and leg upright, eye closed slowly and then head rotate. Another animation is body and leg upright, eye closed slowly and then head rotate so as body bend forward for two times. [0065] It is to be understood that while certain forms of this invention have been illustrated and described, it is not limited thereto, except in so far as such limitations are included in the following claims and allowable equivalents thereof.
A robotic apparatus that interacts with a user and a personal computer (PC) receives inputs from a user and from the PC and reacts and interacts. The interactive apparatus includes a USB interface with the PC to receive power and data such as key strokes, key combinations, email notifications, and web cam events, for example. The interactive apparatus also includes microphones and a phototransistor to detect sounds and movement. The interactive apparatus includes an eye assembly attached to a body and leg, which is responsive to inputs and interactions with the user and PC.
Briefly describe the main idea outlined in the provided context.
[ "CROSS REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of co-pending application Ser.", "No. 61/583,971, filed Jan. 6, 2012, entitled INTERACTIVE APPARATUS.", "[0002] The present invention relates to an interactive personal robotic apparatus and, more particularly, to an interactive robotic apparatus interfaced with a personal computer.", "BACKGROUND [0003] Various personal robots are well known.", "Personal robots that display pre-determined movements are also known.", "Conventional personal robots are typically battery powered and move in predictable ways, and do not positively interact with the user or exhibit a personality.", "This limits their use and utility.", "SUMMARY [0004] The present invention provides a robotic apparatus that interacts with a user and a personal computer (PC).", "The interactive apparatus receives inputs from the user and from the PC and reacts and interacts.", "The interactive apparatus includes a USB interface with the PC to receive power and data such as key strokes, key combinations, email notifications, and web cam events, for example.", "The interactive apparatus also includes microphones and a phototransistor to detect sounds and movement.", "The interactive apparatus includes an eye assembly attached to a body and leg, which is responsive to inputs and interactions with the user and PC.", "DESCRIPTION OF THE DRAWINGS [0005] FIG. 1 is a front elevational view of an interactive apparatus of the present invention.", "[0006] FIG. 2 is a right side view of the interactive apparatus of FIG. 1 .", "[0007] FIG. 3 is a left side view of the interactive apparatus of FIG. 1 .", "[0008] FIG. 4 is a back view of the interactive apparatus of FIG. 1 .", "[0009] FIG. 5 is a top view of the interactive apparatus of FIG. 1 .", "[0010] FIG. 6 is a bottom view of the interactive apparatus of FIG. 1 .", "[0011] FIG. 7 is a perspective view of the interactive apparatus of FIG. 1 .", "[0012] FIG. 8 is a partial exploded perspective view of the interactive apparatus of FIG. 1 .", "[0013] FIG. 9 is an exploded perspective view from right to left of the interactive apparatus of FIG. 1 .", "[0014] FIG. 9A is an enlarged exploded perspective view of the eye assembly of FIG. 9 .", "[0015] FIG. 9B is an enlarged exploded perspective view of the body assembly of FIG. 9 .", "[0016] FIG. 9C is an enlarged exploded perspective view of the leg assembly of FIG. 9 .", "[0017] FIG. 9D is an enlarged exploded perspective view of the base assembly of FIG. 9 .", "[0018] FIG. 9E is an enlarged exploded perspective view of the foot assembly of FIG. 9 .", "[0019] FIG. 10 is a functional block diagram of the control components of the interactive apparatus.", "DETAILED DESCRIPTION [0020] As required, detailed embodiments of the present invention are disclosed herein.", "However, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms.", "The figures are not necessarily to scale;", "some features may be exaggerated or minimized to show details of particular components.", "Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for the claims and/or as a representative basis for teaching one skilled in the art to variously employ the present invention.", "[0021] Moreover, except where otherwise expressly indicated, all numerical quantities in this description and in the claims are to be understood as modified by the word “about”", "in describing the broader scope of this invention.", "Practice within the numerical limits stated is generally preferred.", "Also, unless expressly stated to the contrary, the description of a group or class of materials as suitable or preferred for a given purpose in connection with the invention implies that mixtures or combinations of any two or more members of the group or class may be equally suitable or preferred.", "[0022] Referring to the figures, an interactive apparatus of the present invention is generally indicated by reference numeral 20 .", "The interactive apparatus 20 includes a base assembly 22 , a foot assembly 24 , which may be circular as shown, a leg 26 , a knee 28 , a body assembly 30 , an eye assembly 32 and an eyelid 34 .", "The eye assembly 32 is rotationally coupled to the body assembly 30 , which may be pivotably coupled to the leg assembly 26 at the knee 28 thereby permitting movements about a rotational axis 29 .", "The leg assembly 26 is pivotably coupled to the foot assembly 24 for rotation about a rotational axis 31 .", "[0023] Referring to FIGS. 8 and 9 , the eye assembly 32 includes a lens 36 and a lens mounting plate 38 fastened to mounting posts 40 secured to a back or cap 42 of the eye assembly 32 .", "An eyelid drive motor 44 is coupled to eyelid actuation gears 46 , which are coupled to the eyelid 34 and mounted to the back of the eye 42 .", "An eyelid position sensor 48 coupled to the eyelid drive shaft 50 measures the rotational position of the eyelid 34 around an eyelid axis of rotation 52 .", "A lower eye cover 54 is fastened to the back of the eye 42 and covers the lower edge of the lens 36 .", "The lower eye cover 54 is fastened to a pivot plate 56 , which is rotationally coupled to the body assembly 30 , to connect the eye assembly 32 to the body assembly 30 .", "[0024] The body assembly 30 includes a housing 58 with left 60 and right 62 halves, which are fastened together.", "An eye assembly drive motor 64 is coupled to an eye assembly gear box 66 and mounted to the left half 60 of the housing 58 .", "An eye assembly drive shaft 68 is coupled to the pivot plate 56 to pivot the eye assembly 32 back and forth.", "An eye assembly position sensor 70 is also coupled to the eye assembly drive shaft 68 and measures the rotational position of the eye assembly 32 about an axis of rotation 72 .", "[0025] The body assembly 30 is pivotally coupled to the leg assembly 26 at the knee 28 .", "The leg assembly 26 includes a leg housing 74 with left 76 and right 78 halves fastened together.", "A body assembly drive motor 80 is mounted in the left half 76 of the leg housing 74 .", "A spindle gear 82 coupled to a drive shaft 84 of the body assembly drive motor 80 engages a crown gear 86 .", "A body assembly drive shaft 88 coupled to the crown gear 86 passes through an aperture 90 in an upper end 92 of the right half 78 of the leg assembly housing 74 and engages a slot 94 in a lower end 96 of the right half 62 of the body assembly housing 58 .", "[0026] The crown gear 86 is also coupled to spindle gears 98 , which are coupled to a body assembly position sensor 100 and measures the rotational position of the body assembly 30 .", "[0027] The leg assembly 26 is pivotally coupled to the foot assembly 24 at a lower end 102 of the leg assembly housing 74 .", "A leg assembly drive motor 104 is mounted in a foot gear box 106 .", "A worm gear 108 coupled to a drive shaft 110 of the leg assembly drive motor 104 engages leg assembly drive gears 112 , which are coupled to a leg assembly drive shaft 114 .", "The drive shaft 114 passes through an aperture 116 in the foot gear box 106 to engage a slotted aperture 120 in the lower end 102 of the leg assembly 26 .", "The foot gear box 106 is mounted to a foot pad 118 .", "The lower end 102 of the leg assembly 26 is pivotally coupled to the foot pad 118 by left 122 and right 124 bearings, which engage slots 126 and 128 , respectively.", "The foot assembly 24 also includes a USB port 130 , a head phone jack 132 , and a photo transistor 134 .", "A base plate 119 covers the bottom of the foot pad 118 .", "[0028] The base assembly 22 includes a shell 135 , a pair of speakers 136 and 138 , speaker mounts 137 and 139 mounted behind speaker grills 140 and 142 , respectively.", "Additionally, left 144 and right 146 microphones are mounted on each side of the base 22 .", "[0029] Referring to FIGS. 10 and 8 - 9 , a control circuit, generally indicated by reference numeral 150 , is mounted to the foot assembly 24 .", "The control circuit 150 includes a microprocessor control unit (“MCU”) 152 and an internal memory 154 .", "The MCU 152 receives power and other inputs from a personal computer 156 connected via a USB cable 158 to the USB port 130 .", "The MCU 152 receives input from the photo transducer 134 , microphones 144 and 146 , and from the servos 44 , 64 , 80 and 104 , as well as position sensors 48 , 70 and 100 .", "Input from the left 144 and right 146 microphones permit the MCU 152 to determine the direction/position of the received sound to actuate the servos in response thereto.", "Input from the photo transistor 134 permits the MCU 152 to detect movement to wake up the apparatus 20 , for example, in response to the presence of a user.", "A webcam 161 may be mounted to lens mounting plate 38 behind lens 36 and coupled to MCU 152 .", "[0030] The interactive apparatus 20 receives user interactions or PC 156 via the USB port 130 .", "Based on PC outputs or external inputs, the interactive apparatus 20 may perform motion animations as well as audio output and activation of an LED 160 for a visual output.", "LED 160 may be a single LED or multiple LEDs such as a RGB LED.", "Activities which may trigger interactive apparatus 20 responses may include mouse cursor movements, keyboard inputs, email events, PC audio output, user movements, activation of a webcam, or voice prompts, for example.", "[0031] When the PC 156 is shut down, the interactive apparatus 20 may shut down as well.", "The MCU 152 sends a signal to the eyelid servo 44 to rotate the eyelid 34 to a closed position covering the lens 36 .", "The MCU 152 sends a signal to the body actuator 80 and the leg actuator 104 to rotate forward and back, respectively, to move the interactive apparatus 20 into a folded “resting”", "or “sleeping”", "position.", "When the PC 156 is in a stand by or power save mode, USB power is still available to the MCU 152 .", "The MCU 152 may send signals to the servos to perform “rest”", "or “daydream”", "animations, such as a slow turn of the eye 32 , movement of the body 30 and leg 26 and slow blink of the eyelid 34 , for example.", "While in a “rest”", "mode, the interactive apparatus 20 may make responsive animations to a loud sound or movement detected by the photo transistor 134 , for example.", "[0032] When the PC 156 is turned on and power from the USB 158 is applied to the MCU 152 , the interactive apparatus 20 may exhibit a wake up animation, such as stretching by extending the body 30 and leg 26 , and blinking slowly and widely, by slowly activating the eyelid servo 44 and slowly looking around by actuating the eye assembly servo 64 , making an associated “wake up”", "sound, and activating the LED 160 .", "[0033] When input is detected by the MCU 152 from the USB port 158 , the interactive apparatus 20 may exhibit various “companion”", "mode animations and responses.", "For example, when an email is received, the interactive apparatus may perform an alert animation such as moving up and down quickly by simultaneously actuating the leg servo 104 and body servo 80 .", "[0034] When certain predefined or programmed words are typed via the keyboard and received by the MCU 152 via the USB port 158 , specific animations, activation of the speakers 136 and 138 to output associated sounds, and/or activation of the LED 160 may be performed.", "[0035] For example, when a user has typed words such as “good,” alive,” “native,” “social,” “lucky,” “excellent,” “wonderful,” “perfect,” “right,” “correct,” “classy”", "or “elegant,” a “good”", "animation may be played, such as moving the body 30 quickly forward twice.", "[0036] When the user has typed words such as “bad,” “abuse,” “hate,” “rage,” “cheap,” “dangerous,” “serious,” “risky,” “hazardous”", "or “unsafe,” a “bad”", "animation may be played, such as closing the eye 32 , and moving the body 30 forward and down to a low position, for example.", "[0037] When the user has typed words such as “happy,” “joyful,” delighted,” “merry,” “joyous,” “glad,” and “pleased,” a “happy”", "animation such as moving the body 30 quickly forward and backward, and up and down, may be played.", "[0038] When the user has typed words such as “sad,” “alone,” abject,” “grief,” “hopeless,” “sorry,” “single,” “pity,” “poor,” “joyless,” “woeful,” “depressed,” “tearful”", "or “sorrowful,” for example, a “sad”", "animation may be played such as bending the body 30 and leg 26 backward slowly and then bend forward quickly, and repeating one or more times.", "[0039] When the user has typed a word such as “angry,” “rage,” “paddy,” “mad,” “wrathful”", "or “raging,” an “angry”", "animation such as bending the body 30 and leg 26 backward slowly and then forward quickly, may be played, and repeated one or more times.", "[0040] When the user has typed a word such as “excited,” “heartfelt,” “cordial,” “heated”", "or “crazy,” an “excited”", "animation such as turning the eye 32 quickly and then blinking, may be played.", "[0041] When the user has typed a word “dislike,” “hated,” “disdain,” despised,” “loathe”", "or “scornful,” a “dislike”", "animation by be played such as bending the body 30 backward, opening the eye 32 open slightly and then turning the eye 32 very quickly, for example.", "[0042] When the user has typed a word such as “liked,” “loved,” “nuts,” “favor”", "or “enjoy,” a “liked”", "animation may be played such as turning and blinking the eye 32 quickly.", "[0043] When the user has typed a word such as “sweet,” “naughty,” “lovely,” “cute,” “likeable”", "or “smart,” a “sweet”", "animation may be played such as turning the eye 32 left slowly and then closing the eye 32 very slowly, for example.", "[0044] When the user has typed a word such as “sure,” “obvious,” “resolved,” “trusty,” “yes”", "or “reliable,” a “sure”", "animation may be played such as moving the body 30 left and upright and then blinking the eye 32 twice slowly, for example.", "[0045] When the user has typed a word such as “negative”", "or “passive,” a “negative”", "animation may be played such as bending the body 30 backward, opening the eye 32 slightly and then turning the eye 32 slowly, for example.", "[0046] When the user has typed a word such as “hungry,” a “hungry”", "animation may be played such as turning the eye 32 left and right slowly and then blinking.", "[0047] When the user has typed a word such as “eat,” an “eat”", "animation may be played such as half opening the eye 32 and then blinking very slowly, for example.", "[0048] When the user has typed a word such as “scared,” “agape,” “horror,” “panic,” “fearful,” “awful,” “terrible,” “awesome,” “terrified”", "or “gazed,” a “scared”", "animation may be played such as closing the eye 32 , moving the leg 26 and body 30 to a low position.", "[0049] When the user has typed a word such as “laugh”", "or “absurd,” a “laugh”", "animation may be played such as moving the body 30 forward and backward in small increments of movement, for example.", "[0050] When the user has typed a word such as “cry,” “afraid,” shout”", "or “yell,” a “cry”", "animation may be played such as bending the body 30 forward, turning the eye 32 left and right and then half opening the eye 32 .", "[0051] When the user has typed a word such as “alert,” “suspicious,” “doubted”", "or “puzzled,” an “alert”", "animation may be played such as turning the eye left and right quickly and then stopping at the left side, for example.", "[0052] When the user has typed a word such as “sick,” “old,” “lousy,” “diseased”", "or “unsound,” a “sick”", "animation may be played such as turning the eye 32 left and right very quickly and then opening the eye 32 slightly, for example.", "[0053] When the user has typed a word such as “nasty,” “messy”", "or “rude,” a “nasty”", "animation may be played such as closing the eye 32 and then turning the eye 32 left and right very quickly, for example.", "[0054] When user has typed a word such as “easy,” “pure,” “relaxed,” “refined,” “cozy,” “easeful,” “comfortable”", "or “homelike,” an “easy”", "animation may be played such as bending the body 30 backward and then closing the eye 32 slowly.", "[0055] When the user has typed a word such as “curious”", "or “question,” a “curious”", "animation may be played such as turning the eye 32 to the left, to the right and then back to the center again.", "[0056] When the user has typed a word such as “kind,” “nice,” “affable,” “merciful,” “friendly,” “softhearted,” “brotherly”", "or “genial,” a “kind”", "animation may be played such as bending the body backward, and turning the eye 32 left and right and then blinking, for example.", "[0057] When the user has typed a word such as “sexy”", "or “fair,” a “sexy”", "animation may be played such as turning the eye 32 right or left and then blinking, for example.", "[0058] When the user has typed a word such as “manly,” a “manly”", "animation may be played such as turning the eye 32 left and right slowly and then return to the center position very quickly, for example.", "[0059] When the user has typed a word such as “shy”", "or “ashamed,” a “shy”", "animation may be played such bending the body 30 and leg 26 forward completely, and blinking the eye 32 slowly.", "[0060] When the user has typed a word such as “dog,” a dog-like animation may be played such as bending the body 30 and leg 26 backward and then bending the body 30 forward and backward in sync with a dog sound generated by the MCU 152 and output on speakers 136 and 138 .", "[0061] When the user has typed a word such as “pig,” a pig-like animation may be played such as bending the body 30 and leg 26 backward, and closing the eye 32 slowly, and then bending the body 30 forward and backward in sync with a pig sound generated by the MCU 152 and output on speakers 136 and 138 .", "[0062] When the user has typed a word such as “cat,” a cat-like animation may be played such as bending the body 30 and leg 26 backward, then bending the body 30 forward slightly, and then turning the eye 32 left and right, for example.", "[0063] When a web cam is being used, the MCU 152 will actuate the eye assembly servo 64 to turn to the direction of the speaker's voice using input from the microphones 144 and 146 , for example.", "[0064] When music is detected by the MCU 152 , the MCU 152 will actuate servos 44 , 66 , 80 and 104 to perform a dancing animation in sync with the beat of the music, for example.", "Other sound input from the microphones 144 and 146 as detected by the MCU 152 may produce additional animations.", "One animation is body and leg upright, eye closed slowly and then head rotate.", "Another animation is body and leg upright, eye closed slowly and then head rotate so as body bend forward for two times.", "[0065] It is to be understood that while certain forms of this invention have been illustrated and described, it is not limited thereto, except in so far as such limitations are included in the following claims and allowable equivalents thereof." ]
REFERENCE TO RELATED APPLICATIONS [0001] This application claims all benefits accruing under 35 U.S.C. §119 from Taiwan Patent Application No. 101136429, filed on Oct. 3, 2012 in the Taiwan Intellectual Property Office. The contents of the Taiwan Application are hereby incorporated by reference. BACKGROUND [0002] 1. Technical Field [0003] The disclosure generally relates to touch panels, and particularly relates to touch sensing devices and methods applied to touch panels. [0004] 2. Description of Related Art [0005] In recent years, touch panels serving as input devices are gradually applied to various electronic devices such as mobile phones, personal digital assistants (PDAs), and tablet personal computers (tablet PC). When a touch panel serves as an input device, several operation instructions can be applied for instructing an electronic device to perform various operations. For example, sliding on the touch panel means moving, tapping the touch panel once means clicking a left mouse button, tapping the touch panel twice means clicking a right mouse button, and tapping and sliding on the touch panel means dragging. However, in order to perform the foregoing operation instructions smoothly, a touched position at each of time points needs to be accurately detected on the touch panel so that which operation instruction to be performed can be determined. For example, a direction and a distance are determined according to touched positions at successive time points when sliding is performed on the touch panel. [0006] In addition, the touch panel is often used in a portable electronic device, thus power consumption of the touch panel is an important factor that affects efficiency of the electronic device. BRIEF DESCRIPTION OF THE DRAWINGS [0007] Many aspects of the embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the views. [0008] FIG. 1 is a block diagram of a touch sensing device in accordance with one embodiment of the present disclosure. [0009] FIG. 2 is a schematic diagram of a capacitive touch panel. [0010] FIG. 3 is a table showing horizontal and vertical sensing signals generated by a touch panel. [0011] FIG. 4 is a flowchart showing one embodiment of a touch sensing method. [0012] FIG. 5 is a flowchart showing another embodiment of a touch sensing method. DETAILED DESCRIPTION [0013] The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which like reference numerals indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references can mean “at least one.” [0014] In general, the word “module,” as used herein, refers to logic embodied in hardware or firmware, or to a collection of software instructions, written in a programming language such as Java, C, or assembly. One or more software instructions in the modules may be embedded in firmware, such as in an erasable-programmable read-only memory (EPROM). The modules described herein may be implemented as either software and/or hardware modules and may be stored in any type of non-transitory computer-readable medium or other storage device. Some non-limiting examples of non-transitory computer-readable media are compact discs (CDs), digital versatile discs (DVDs), Blu-Ray discs, Flash memory, and hard disk drives. [0015] FIG. 1 shows one embodiment of a touch sensing device 10 . The touch sensing device 10 includes a touch panel 12 and a calculation unit 16 . The touch sensing device 10 serves as an input device of a mobile phone, a personal digital assistant (PDA), a tablet personal computer (tablet PC), or the like. [0016] The touch panel 12 includes a plurality of vertical sensing lines and a plurality of horizontal sensing lines. Each of the vertical sensing lines corresponds to a horizontal coordinate. Each of the horizontal sensing lines corresponds to a vertical coordinate. In other words, the horizontal and vertical sensing lines are alternately distributed on the touch panel 12 to form a two-dimensional (2D) coordinate system. [0017] When a user touches the touch panel 12 , the vertical and horizontal sensing lines are respectively sensed to generate corresponding vertical and horizontal sensing signals. The vertical sensing signals represent touch intensities sensed by the touch panel 12 at corresponding horizontal coordinates. The horizontal sensing signals represent touch intensities sensed at corresponding vertical coordinates. [0018] In this embodiment, the touch panel 12 is a capacitive touch panel as illustrated in FIG. 2 . The capacitive touch panel 12 comprises n vertical sensing lines and m horizontal sensing lines (e.g. n=m=5 in FIG. 2 ) corresponding to horizontal coordinates X1 to X5 and vertical coordinates Y1 to Y5. In the capacitive touch panel 12 , each of the vertical and horizontal sensing lines possesses an equivalent capacitor. When a user touches the capacitive touch panel 12 , capacitance values of the equivalent capacitors are changed, and the vertical and horizontal sensing signals generated by the vertical and horizontal sensing lines represent capacitance variances of equivalent capacitors. As capacitance variance of an equivalent capacitor of a vertical or horizontal sensing line becomes greater, it indicates that a corresponding horizontal or vertical horizontal is closer to the touched position. [0019] Referring to FIG. 3 , an example of a table showing horizontal and vertical sensing signals generated by the touch panel 12 is illustrated. In FIG. 3 , five vertical sensing lines corresponding to horizontal coordinates X1 to X5 generate five vertical sensing signals a 1 to a 5 , and five horizontal sensing lines corresponding to vertical coordinates Y1 to Y5 generate five horizontal sensing signals b 1 to b 5 . [0020] The calculation unit 16 is coupled to the touch panel 12 . The calculation unit 16 calculates the touched position on the touch panel 12 according to the vertical and horizontal sensing signals generated by the touch panel 12 . [0021] In a first embodiment, the calculation unit 16 calculates a horizontal coordinate X and a vertical coordinate Y of the touched position on the touch panel 12 according to the following formulas: [0000] X = a 1 × X 1 + a 2 × X 2 + … + a n × X n a 1 + a 2 + … + a n ,  Y = b 1 × Y 1 + b 2 × Y 2 + … + b m × Y m b 1 + b 2 + … + b m , [0000] wherein a 1 , a 2 , . . . , a n represent the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, b 1 , b 2 , . . . , b m represent the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines, X 1 , X 2 , . . . , X n represent horizontal coordinates corresponding to the plurality vertical sensing lines, and Y 1 , Y 2 , . . . , Y m represent vertical coordinates corresponding to the plurality of horizontal sensing lines, where n and m are integers greater than two. [0022] In order to reduce need for time-consuming and intermediate data storage, the calculation unit 16 filters the vertical and horizontal sensing signals generated by the touch panel 12 before the calculation of the touched position. The calculation unit 16 may define a vertical threshold and a horizontal threshold. The calculation unit 16 compares each of the vertical sensing signals with the vertical threshold, and compares each of the horizontal sensing signals with the horizontal threshold. The calculation unit 16 discards any vertical sensing signal which is smaller than the vertical threshold, and discards any horizontal sensing signal which is smaller than the horizontal threshold. The discarded sensing signals do not participate in the calculation of the touched position. Thus, noise components contained in the vertical and horizontal sensing signals are relieved. [0023] In a second embodiment, the calculation unit 16 selects the top largest vertical sensing signals, r, from the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, and selects the top largest horizontal sensing signals, s, from the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines (where r and s are integers greater than two). The calculation unit 16 calculates a horizontal coordinate X and a vertical coordinate Y of the touched position on the touch panel 12 according to the following formulas: [0000] X = A 1 × X 1 + A 2 × X 2 + … + A r × X r A 1 + A 2 + … + A r ,  Y = B 1 × Y 1 + B 2 × Y 2 + … + B s × Y s B 1 + B 2 + … + B s , [0000] wherein A 1 , A 2 , . . . , A r represent the top r largest vertical sensing signals selected from the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, B 1 , B 2 , . . . , B s represent the top s largest horizontal sensing signals selected from the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines, X 1 , X 2 , . . . , X r represent horizontal coordinates corresponding to the vertical sensing lines corresponding to the selected top largest vertical sensing signals, r, and Y 1 , Y 2 , . . . , Y s represent vertical coordinates corresponding to the horizontal sensing lines corresponding to the selected top largest horizontal sensing signals, s, where r and s are integers greater than two. [0024] After calculating the horizontal and vertical coordinates of the touched position, the calculation unit 16 transmits the information to a microprocessor (not shown) in an electronic device, so as to interpret the information (e.g. moving or dragging) to perform a corresponding operation accordingly. [0025] FIG. 4 is a flowchart showing one embodiment of a touch sensing method. The method includes the following steps. [0026] In step S 401 , the touch panel 12 senses a touch. The horizontal and vertical sensing lines of the touch panel 12 generate a plurality of vertical and horizontal sensing signals. [0027] In step S 402 , the calculation unit 16 calculates a horizontal coordinate X and a vertical coordinate Y of a touched position on the touch panel 12 according to the following formulas: [0000] X = a 1 × X 1 + a 2 × X 2 + … + a n × X n a 1 + a 2 + … + a n ,  Y = b 1 × Y 1 + b 2 × Y 2 + … + b m × Y m b 1 + b 2 + … + b m , [0000] wherein a 1 , a 2 , . . . , a n represent the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, b 1 , b 2 , . . . , b m represent the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines, X 1 , X 2 , . . . , X n represent horizontal coordinates corresponding to the plurality vertical sensing lines, and Y 1 , Y 2 , . . . , Y m represent vertical coordinates corresponding to the plurality of horizontal sensing lines, where n and m are integers greater than two. [0028] In order to reduce need for data storage, the calculation unit 16 filters the vertical and horizontal sensing signals generated by the touch panel 12 before the calculation of the touched position. The calculation unit 16 defines a vertical threshold and a horizontal threshold. The calculation unit 16 compares each of the vertical sensing signals with the vertical threshold, and compares each of the horizontal sensing signals with the horizontal threshold. The calculation unit 16 discards any vertical sensing signal which is smaller than the vertical threshold, and any horizontal sensing signal which is smaller than the horizontal threshold. The discarded sensing signals do not participate in the calculation of the touched position. Thus, noise components contained in the vertical and horizontal sensing signals are relieved. [0029] FIG. 5 is a flowchart showing another embodiment of a touch sensing method. The method includes the following steps. [0030] In step S 501 , the touch panel 12 senses a touch. The horizontal and vertical sensing lines of the touch panel 12 generate a plurality of vertical and horizontal sensing signals. [0031] In step S 502 , the calculation unit 16 selects the top largest vertical sensing signals, r, from the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, and selects the top largest horizontal sensing signals, s, from the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines (where r and s are integers greater than two). [0032] In step S 502 , the calculation unit 16 calculates a horizontal coordinate X and a vertical coordinate Y of the touched position on the touch panel 12 according to the following formulas: [0000] X = A 1 × X 1 + A 2 × X 2 + … + A r × X r A 1 + A 2 + … + A r ,  Y = B 1 × Y 1 + B 2 × Y 2 + … + B s × Y s B 1 + B 2 + … + B s , [0000] wherein A 1 , A 2 , . . . , A r represent the top r largest vertical sensing signals selected from the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, B 1 , B 2 , . . . , B s represent the top s largest horizontal sensing signals selected from the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines, X i , X 2 , . . . , X r represent horizontal coordinates corresponding to the vertical sensing lines corresponding to the selected top largest vertical sensing signals, r, and Y i , Y 2 , . . . , Y s represent vertical coordinates corresponding to the horizontal sensing lines corresponding to the selected top largest horizontal sensing signals, s, where r and s are integers greater than two. [0033] Although numerous characteristics and advantages have been set forth in the foregoing description of embodiments, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in the matters of arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. [0034] In particular, depending on the embodiment, certain steps or methods described may be removed, others may be added, and the sequence of steps may be altered. [0035] The description and the claims drawn for or in relation to a method may give some indication in reference to certain steps. However, any indication given is only to be viewed for identification purposes, and is not necessarily a suggestion as to an order for the steps.
A touch sensing device capable of accurately detecting a touched position on a touch panel includes a touch panel and a calculation unit. The touch panel having a plurality of horizontal sensing lines and vertical sensing lines generates a plurality of horizontal and vertical sensing signals in response to a touch on the touch panel. The calculation unit determines a touched position on the touch panel according to the horizontal and vertical sensing signals. A touch sensing method is also provided.
Briefly describe the main invention outlined in the provided context.
[ "REFERENCE TO RELATED APPLICATIONS [0001] This application claims all benefits accruing under 35 U.S.C. §119 from Taiwan Patent Application No. 101136429, filed on Oct. 3, 2012 in the Taiwan Intellectual Property Office.", "The contents of the Taiwan Application are hereby incorporated by reference.", "BACKGROUND [0002] 1.", "Technical Field [0003] The disclosure generally relates to touch panels, and particularly relates to touch sensing devices and methods applied to touch panels.", "[0004] 2.", "Description of Related Art [0005] In recent years, touch panels serving as input devices are gradually applied to various electronic devices such as mobile phones, personal digital assistants (PDAs), and tablet personal computers (tablet PC).", "When a touch panel serves as an input device, several operation instructions can be applied for instructing an electronic device to perform various operations.", "For example, sliding on the touch panel means moving, tapping the touch panel once means clicking a left mouse button, tapping the touch panel twice means clicking a right mouse button, and tapping and sliding on the touch panel means dragging.", "However, in order to perform the foregoing operation instructions smoothly, a touched position at each of time points needs to be accurately detected on the touch panel so that which operation instruction to be performed can be determined.", "For example, a direction and a distance are determined according to touched positions at successive time points when sliding is performed on the touch panel.", "[0006] In addition, the touch panel is often used in a portable electronic device, thus power consumption of the touch panel is an important factor that affects efficiency of the electronic device.", "BRIEF DESCRIPTION OF THE DRAWINGS [0007] Many aspects of the embodiments can be better understood with reference to the following drawings.", "The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the embodiments.", "Moreover, in the drawings, like reference numerals designate corresponding parts throughout the views.", "[0008] FIG. 1 is a block diagram of a touch sensing device in accordance with one embodiment of the present disclosure.", "[0009] FIG. 2 is a schematic diagram of a capacitive touch panel.", "[0010] FIG. 3 is a table showing horizontal and vertical sensing signals generated by a touch panel.", "[0011] FIG. 4 is a flowchart showing one embodiment of a touch sensing method.", "[0012] FIG. 5 is a flowchart showing another embodiment of a touch sensing method.", "DETAILED DESCRIPTION [0013] The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which like reference numerals indicate similar elements.", "It should be noted that references to “an”", "or “one”", "embodiment in this disclosure are not necessarily to the same embodiment, and such references can mean “at least one.”", "[0014] In general, the word “module,” as used herein, refers to logic embodied in hardware or firmware, or to a collection of software instructions, written in a programming language such as Java, C, or assembly.", "One or more software instructions in the modules may be embedded in firmware, such as in an erasable-programmable read-only memory (EPROM).", "The modules described herein may be implemented as either software and/or hardware modules and may be stored in any type of non-transitory computer-readable medium or other storage device.", "Some non-limiting examples of non-transitory computer-readable media are compact discs (CDs), digital versatile discs (DVDs), Blu-Ray discs, Flash memory, and hard disk drives.", "[0015] FIG. 1 shows one embodiment of a touch sensing device 10 .", "The touch sensing device 10 includes a touch panel 12 and a calculation unit 16 .", "The touch sensing device 10 serves as an input device of a mobile phone, a personal digital assistant (PDA), a tablet personal computer (tablet PC), or the like.", "[0016] The touch panel 12 includes a plurality of vertical sensing lines and a plurality of horizontal sensing lines.", "Each of the vertical sensing lines corresponds to a horizontal coordinate.", "Each of the horizontal sensing lines corresponds to a vertical coordinate.", "In other words, the horizontal and vertical sensing lines are alternately distributed on the touch panel 12 to form a two-dimensional (2D) coordinate system.", "[0017] When a user touches the touch panel 12 , the vertical and horizontal sensing lines are respectively sensed to generate corresponding vertical and horizontal sensing signals.", "The vertical sensing signals represent touch intensities sensed by the touch panel 12 at corresponding horizontal coordinates.", "The horizontal sensing signals represent touch intensities sensed at corresponding vertical coordinates.", "[0018] In this embodiment, the touch panel 12 is a capacitive touch panel as illustrated in FIG. 2 .", "The capacitive touch panel 12 comprises n vertical sensing lines and m horizontal sensing lines (e.g. n=m=5 in FIG. 2 ) corresponding to horizontal coordinates X1 to X5 and vertical coordinates Y1 to Y5.", "In the capacitive touch panel 12 , each of the vertical and horizontal sensing lines possesses an equivalent capacitor.", "When a user touches the capacitive touch panel 12 , capacitance values of the equivalent capacitors are changed, and the vertical and horizontal sensing signals generated by the vertical and horizontal sensing lines represent capacitance variances of equivalent capacitors.", "As capacitance variance of an equivalent capacitor of a vertical or horizontal sensing line becomes greater, it indicates that a corresponding horizontal or vertical horizontal is closer to the touched position.", "[0019] Referring to FIG. 3 , an example of a table showing horizontal and vertical sensing signals generated by the touch panel 12 is illustrated.", "In FIG. 3 , five vertical sensing lines corresponding to horizontal coordinates X1 to X5 generate five vertical sensing signals a 1 to a 5 , and five horizontal sensing lines corresponding to vertical coordinates Y1 to Y5 generate five horizontal sensing signals b 1 to b 5 .", "[0020] The calculation unit 16 is coupled to the touch panel 12 .", "The calculation unit 16 calculates the touched position on the touch panel 12 according to the vertical and horizontal sensing signals generated by the touch panel 12 .", "[0021] In a first embodiment, the calculation unit 16 calculates a horizontal coordinate X and a vertical coordinate Y of the touched position on the touch panel 12 according to the following formulas: [0000] X = a 1 × X 1 + a 2 × X 2 + … + a n × X n a 1 + a 2 + … + a n ,  Y = b 1 × Y 1 + b 2 × Y 2 + … + b m × Y m b 1 + b 2 + … + b m , [0000] wherein a 1 , a 2 , .", ", a n represent the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, b 1 , b 2 , .", ", b m represent the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines, X 1 , X 2 , .", ", X n represent horizontal coordinates corresponding to the plurality vertical sensing lines, and Y 1 , Y 2 , .", ", Y m represent vertical coordinates corresponding to the plurality of horizontal sensing lines, where n and m are integers greater than two.", "[0022] In order to reduce need for time-consuming and intermediate data storage, the calculation unit 16 filters the vertical and horizontal sensing signals generated by the touch panel 12 before the calculation of the touched position.", "The calculation unit 16 may define a vertical threshold and a horizontal threshold.", "The calculation unit 16 compares each of the vertical sensing signals with the vertical threshold, and compares each of the horizontal sensing signals with the horizontal threshold.", "The calculation unit 16 discards any vertical sensing signal which is smaller than the vertical threshold, and discards any horizontal sensing signal which is smaller than the horizontal threshold.", "The discarded sensing signals do not participate in the calculation of the touched position.", "Thus, noise components contained in the vertical and horizontal sensing signals are relieved.", "[0023] In a second embodiment, the calculation unit 16 selects the top largest vertical sensing signals, r, from the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, and selects the top largest horizontal sensing signals, s, from the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines (where r and s are integers greater than two).", "The calculation unit 16 calculates a horizontal coordinate X and a vertical coordinate Y of the touched position on the touch panel 12 according to the following formulas: [0000] X = A 1 × X 1 + A 2 × X 2 + … + A r × X r A 1 + A 2 + … + A r ,  Y = B 1 × Y 1 + B 2 × Y 2 + … + B s × Y s B 1 + B 2 + … + B s , [0000] wherein A 1 , A 2 , .", ", A r represent the top r largest vertical sensing signals selected from the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, B 1 , B 2 , .", ", B s represent the top s largest horizontal sensing signals selected from the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines, X 1 , X 2 , .", ", X r represent horizontal coordinates corresponding to the vertical sensing lines corresponding to the selected top largest vertical sensing signals, r, and Y 1 , Y 2 , .", ", Y s represent vertical coordinates corresponding to the horizontal sensing lines corresponding to the selected top largest horizontal sensing signals, s, where r and s are integers greater than two.", "[0024] After calculating the horizontal and vertical coordinates of the touched position, the calculation unit 16 transmits the information to a microprocessor (not shown) in an electronic device, so as to interpret the information (e.g. moving or dragging) to perform a corresponding operation accordingly.", "[0025] FIG. 4 is a flowchart showing one embodiment of a touch sensing method.", "The method includes the following steps.", "[0026] In step S 401 , the touch panel 12 senses a touch.", "The horizontal and vertical sensing lines of the touch panel 12 generate a plurality of vertical and horizontal sensing signals.", "[0027] In step S 402 , the calculation unit 16 calculates a horizontal coordinate X and a vertical coordinate Y of a touched position on the touch panel 12 according to the following formulas: [0000] X = a 1 × X 1 + a 2 × X 2 + … + a n × X n a 1 + a 2 + … + a n ,  Y = b 1 × Y 1 + b 2 × Y 2 + … + b m × Y m b 1 + b 2 + … + b m , [0000] wherein a 1 , a 2 , .", ", a n represent the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, b 1 , b 2 , .", ", b m represent the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines, X 1 , X 2 , .", ", X n represent horizontal coordinates corresponding to the plurality vertical sensing lines, and Y 1 , Y 2 , .", ", Y m represent vertical coordinates corresponding to the plurality of horizontal sensing lines, where n and m are integers greater than two.", "[0028] In order to reduce need for data storage, the calculation unit 16 filters the vertical and horizontal sensing signals generated by the touch panel 12 before the calculation of the touched position.", "The calculation unit 16 defines a vertical threshold and a horizontal threshold.", "The calculation unit 16 compares each of the vertical sensing signals with the vertical threshold, and compares each of the horizontal sensing signals with the horizontal threshold.", "The calculation unit 16 discards any vertical sensing signal which is smaller than the vertical threshold, and any horizontal sensing signal which is smaller than the horizontal threshold.", "The discarded sensing signals do not participate in the calculation of the touched position.", "Thus, noise components contained in the vertical and horizontal sensing signals are relieved.", "[0029] FIG. 5 is a flowchart showing another embodiment of a touch sensing method.", "The method includes the following steps.", "[0030] In step S 501 , the touch panel 12 senses a touch.", "The horizontal and vertical sensing lines of the touch panel 12 generate a plurality of vertical and horizontal sensing signals.", "[0031] In step S 502 , the calculation unit 16 selects the top largest vertical sensing signals, r, from the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, and selects the top largest horizontal sensing signals, s, from the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines (where r and s are integers greater than two).", "[0032] In step S 502 , the calculation unit 16 calculates a horizontal coordinate X and a vertical coordinate Y of the touched position on the touch panel 12 according to the following formulas: [0000] X = A 1 × X 1 + A 2 × X 2 + … + A r × X r A 1 + A 2 + … + A r ,  Y = B 1 × Y 1 + B 2 × Y 2 + … + B s × Y s B 1 + B 2 + … + B s , [0000] wherein A 1 , A 2 , .", ", A r represent the top r largest vertical sensing signals selected from the plurality of vertical sensing signals generated by the plurality of vertical sensing lines, B 1 , B 2 , .", ", B s represent the top s largest horizontal sensing signals selected from the plurality of horizontal sensing signals generated by the plurality of horizontal sensing lines, X i , X 2 , .", ", X r represent horizontal coordinates corresponding to the vertical sensing lines corresponding to the selected top largest vertical sensing signals, r, and Y i , Y 2 , .", ", Y s represent vertical coordinates corresponding to the horizontal sensing lines corresponding to the selected top largest horizontal sensing signals, s, where r and s are integers greater than two.", "[0033] Although numerous characteristics and advantages have been set forth in the foregoing description of embodiments, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in the matters of arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.", "[0034] In particular, depending on the embodiment, certain steps or methods described may be removed, others may be added, and the sequence of steps may be altered.", "[0035] The description and the claims drawn for or in relation to a method may give some indication in reference to certain steps.", "However, any indication given is only to be viewed for identification purposes, and is not necessarily a suggestion as to an order for the steps." ]
BACKGROUND OF THE INVENTION This invention relates to an apparatus and method for storing, transporting and installing a sheet-like member between two adjacent opposing planar members. More particularly, this invention relates to an apparatus and method for storing, transporting and installing membrane members between electrode frame members of an electrolyzer of the filter press type. Electrolytic cells of the filter press-type are known to be used for the electrolysis of aqueous salt solutions and have been commercially employed for the production of chlorine and caustic from brine. The filter press type electrolyzer for electrolysis of an aqueous salt solution commonly employ a plurality of electrolytic cell frame members or units with electrodes held thereto and assembled in a filter press type arrangement, separated from each other by membranes, diaphragms or microporous separators, forming a plurality of anolyte and catholyte compartments. The electrodes used in the cells are generally either monopolar or bipolar electrodes. Membranes typically used in the cells are generally available in sheet form and have ion exchange properties, for example, membrane materials employed in the cells are such as those marketed by E. I. duPont de Nemours and Company under the trademark NAFION and by Asahi Glass Company Ltd. under the trademark FLEMION. In ion-exchange membrane chlorine cells of the filter press type, some ion-exchange membranes used in the cells have to be placed between the bipolar or monopolar chlorine cell units and remain wet with salt water as long as possible until the cells begin to produce chlorine and caustic product. Membranes can be ruined, for example, if the membrane is exposed to the atmosphere for any great length of time and it dries out. A membrane can dry out in the length of time it takes to install the membrane in an electrolyzer. Some electrolyzers are made up of as many as 60 or more electrolytic cell units in series and therefore 60 or more of the ion-exchange membranes have to be installed between the cells. The membrane in sheet form is very similar to fabric, normally in a size of about 4 feet by 10 feet or 5 feet by 12 feet. When electrolyzers utilizing the membranes are located outdoors, the installation of the membranes within the cells would expose the membranes to dust, wind and sun. Previous techniques of installing the membranes included tentering the membrane by hand beside the electrolyzer and then raising the membranes up and over the electrolytic cell units. The membrane, when using this technique, is exposed to the outdoor environment and is lowered from the top of the cell units down between the cell units. Handling problems do occur due to having to raise and position the membrane over the chlorine cell units and being careful to avoid wrinkling or tearing the membrane. It would be desirous to provide a container which would conceal and store the membrane until the moment required for installing the membrane between the cell units to minimize the membrane being in contact with the elements such as wind and sun which could damage the membrane before it is used. The advantage of the present invention over the prior art methods is that the exposure of the membranes to the outdoor environment and wrinkling of the membranes is minimized when being suspended openly. SUMMARY OF THE INVENTION This invention is directed to a combination storage, transportation and installation container apparatus for sheet-like members such as ion exchange membranes for bipolar or monopolar ion-exchange membrane chlorine cells. The container includes (a) at least four side walls and a bottom and is adapted for receiving at least one sheet-like member in a substantially planar position inside the container and (b) a roller tension bar member disposed across at least two parallel side walls of the container, the tension bar member adapted for guiding a sheet-like member being removed from inside the container to a use point. The container protects the membrane from the environment, and maintains the membrane wet if desired. The container may be used to install membranes in electrolzer by pulling out of the membrane from the container directly into the area between an anode and cathode of an electrolytic cell for mounting the membrane into place. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a container of the present invention. FIG. 2 is a cross-sectional view taken along line 2--2 of FIG. 1 showing a container of the present invention. FIG. 3 is side view showing a container of the present invention being used to install a membrane in an electrolysis cell. FIG. 4 is a fragmentary side view showing another embodiment of a roller tension bar in a container of the present invention. FIG. 5 is a side view taken along line 5--5 of FIG. 4 showing the roller tension bar of FIG. 4. FIG. 6 is a top view of the roller tension bar of FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIGS. 1 and 2, there is shown a container of the present invention, generally indicated by numeral 10, with several sheet-like members 21 placed in the container 10. The container 10 includes four side walls 11-14 and a bottom 15. In this instance the container is box-like and rectangular in shape with side walls 11 and 12 parallel to each other and 13 and 14 parallel to each other. Other shapes of the container, such as square or circular, can be used. This will depend, to some extent, on the shape of the sheet-like member. Roller bar support members 16 on side walls 11 and 12 hold a roller tension bar member 17 extending on top of and across the length of the container 10. The roller tension bar 17 is adapted for guiding a sheet-like member such as a membrane 21 and keeping it planar as it exits the container 10. The roller tension bar 17 is preferably rotatably mounted in the container 10. One side of the membrane contacts the length of the roller tension bar 17 as the membrane is removed from the inside of the container 10 to a use point outside the container. The roller tension bar 17 preferably rotates as the membrane, for example, is pulled across the surface of the roller bar to maintain contact with the surface of one side of the membrane until it is removed from the container. It is preferred to place roller means generally indicated by numeral 18 on the bottom of the container 10 for ease of moving the container from one location to another. In this instance, the roller means 18 includes a support frame 19 with casters 20 attached to the bottom of the support frame 19. The container 10 is removably mounted on the support frame 19 or, if desired, the bottom wall 15 may be attached to the support frame 19. The roller means 18 allows the container 10 to be rolled to a use location. In another embodiment, the casters 20 may be attached directly to the bottom wall 15 of the container 10. Other means for moving the container to the location for its use can also be used such as by lifting the container with a lifting device. The materials of construction for the container and support frame are conventional such as metal or plastic having sufficient strength to support the handling of loads placed thereon. The container 10 can contain a single or plurality of sheet-like members such as membranes 21 with or without a clamping means (not shown) attached to the top edge of each membrane for ease of removing the membrane from the container. The membranes 21 are preferably ion-exchange membranes. When a plurality of electrolytic cell units are assembled in operable combination, an ion exchange membrane is positioned between adjoining electrolytic units. The type of ion exchange membrane used in the present invention is not critical. Representative of the types of ion exchange membrane suitable for use in assembling a plurality of electrolytic units are disclosed in the following U.S. Pat. Nos. 3,909,378: 4,025,405: 4,065,366; 4,116,888; 4,123,336: 4,126,588; 4,151,053: 4,176,215: 4,178,218; 4,192,725: 4,209,635: 4,212,713: 4,251,333: 4,270,996: 4,329,435: 4,330,654: 4,337,137: 4,337,211: 4,340,680; 4,357,218; 4,358,412: and 4,358,545. These patents are hereby incorporated by reference for the purpose of the membranes they disclose. The ion exchange membrane 21 may preferably contain sulfonic ion exchange groups, carboxylic ion exchange groups, or both sulfonic and carboxylic acid ion exchange groups. Optionally, the ion exchange membrane may be a bi-layer membrane having one type of ion exchange active sites in one layer and another type of ion exchange active sites in the other layer. The membrane may be reinforced to impair deforming during electrolysis or it may be unreinforced to maximize the electrical conductivity throughout the membrane. In placing the membrane in the container 10, it is preferred to lay the membranes 21 planar to each other in a layered fashion with a flexible protective sheet member 22 interposed between the membranes 21. Optionally, one sheet member 22 may cover the bottom of the container 10 to avoid abrasive damage to the membranes 21. Any material which is used for the sheet member 22 should be inert to alkaline solution used in the container 10 and non-abrasive to the membrane 21. The protective sheet members 22 may be made of, for example, a plastic such as polyethylene or fluorocarbon plastic such as TEFLON®. Preferably, a single protective sheet cover member 22 is used to cover a single membrane 21 and is positioned between the membranes for separating from each other and protecting the membranes from abrasion from each other. The container 10 may contain a liquid for maintaining the membrane wetted until it is used. The liquid may be, for example, an aqueous alkaline solution such as NaCl solution (brine), weak caustic solution and sodium carbonate solution and the like. The placing of the membrane 21 and protective sheet member 22 should be carried out inside an environmentally controlled handling facility such as a clean, air-conditioned or heated room to prevent exposing the membranes to the elements. A protective sheet member 22 is laid on top of the last membrane 21 in the container or the container is covered with a removable container top (not shown) to keep out dust and sunlight as the container is transported outdoors to a vicinity near the electrolyzer area. With reference to FIG. 3, there is shown an electrolyzer generally indicated as numeral 30 with a container 10 underneath the electrolyzer 30. Generally, the electrolyzer 30 comprises a series of electrolytic cell units 31 supported on rails 32 which in turn are supported by two stationary platens 33 and 34. A compressor means such as a moveable platen 35 attached to hydraulic jacks 36 and a hydraulic reservoir 37 is used to compress the electrolytic cell units 31 together in a fluid-tight arrangement. The container 10 may be transported to the electrolyzer 30, for example, by fork lift or the container 10 may be rolled out to the electrolyzer work area via the roller means 18. With the container positioned adjacent to the series of electrolytic cell units, the container 10 is then set underneath the series of electrolytic cell units by rolling the container via its roller coasters 20. Preferably, the coasters 20 should allow the container to be moved bi-directionally. Preferred filter press type electrolytic cell units for employing the present invention are bipolar or monopolar membrane cells in which the electrolytic cell units are oriented vertically as shown in FIG. 3. Suitable bipolar filter press membrane electrolytic cell units include, for example, those described in U.S. Pat. No. 4,488,946, issued Dec. 18, 1984 to Morris et al. Suitable filter press monopolar membrane electrolytic cells include, for example, those described in U.S. Pat. No. 4,056,458, issued Nov. 1, 1977, to G. R. Pohto et al.; U.S. Pat. No. 4,210,516, issued July 1, 1980, to L. Mose et al. and U.S. Pat. No. 4,217,199, issued Aug. 12, 1980, to H. Cunningham. The electrolytic cell comprises an anode or a plurality of anodes and a cathode or a plurality of cathodes, and one or more gaskets of the present invention compressed together with a membrane between each anode and adjacent cathode which divides the cell into separate anode and cathode compartments. The electrolytic cell is equipped with means for charging electrolyte to the cell and with means for removing the products of electrolysis from the cell. In particular, the anode compartments of the cell are provided with means for feeding aqueous alkali metal chloride electrolyte to the cell, suitably from a common header, and with means for removing products of electrolysis from the cell. Similarly, the cathode compartments of the cell are provided with means for removing products of electrolysis from the cell, and optionally with means for feeding water or other fluid to the cell. The electrolysis process may be operated by charging electrolyte to the electrolytic cell, electrolyzing the electrolyte therein, and removing the products of electrolysis from the electrolytic cell. Again, with reference to FIG. 3, in a preferred embodiment of carrying out a process of the present invention, the container 10 is rolled under the series of cells 30 and positioned directly below a space between a cell-to-cell opening. A rope or pulling means (not shown) is then lowered down through the space created by separated cell units from overhead the cell units. The pulling means are held by operating personnel who are standing above the opening. The top edge of the first membrane 21 is attached to the pulling means. The pulling means is then used to pull the membrane up through the opening manually. As the pulling means moves upward, the membrane 21 is pulled out of the container 10 and against the underside of the roller tension bar 17. The protective sheet member 22 is placed between the membrane 21 and the tension bar 17. The membrane 21 is pulled from the container 10 until the free bottom edge can be held by hand and located properly against the bipolar cell unit. The cell-to-cell opening is closed up after proper positioning of the membrane against the gaskets and the cells are pressed into position by a conventional cell press means. The container is then repositioned, if required, underneath the next cell-to-cell opening and the process is repeated until all membranes in the container are used. The container is then rolled out from under the series of cells and transferred back to the handling room by forklift or casters. Several more membranes are laid in the container as described above with alternate layers of polyethylene and the handling process is repeated at the series site until the desired number of membranes are installed in an electrolyzer unit. Referring to FIGS. 4, 5 and 6, there is shown another embodiment of a roller tension bar 40 including a pipe member 41 with a pipe member 42 concentrically disposed therein. The pipe member 41 is wrapped around pipe member 42 and is capable of freely spinning around the pipe member 42, i.e., it is not attached to the pipe member 42, however pipe member 41 could be securely attached to pipe member 42 if desired. Roller means 43 are rotatably mounted on a support member 44 which is preferably attached to a bottom member 45 with casters 46. A container 47 is mounted on the bottom member 45. The roller tension bar 40 is rotatably mounted on the roller means 43. In operation, the membrane surface contacts the tension 40 bar which rotates on the roller means to minimize abrasion and frictional forces which may damage the membrane as it exits the container. A stop piece 48 prevents the tension bar 40 from sliding off the roller means 43 and maintains the tension bar 40 in position.
A storage, transportation and installation apparatus for ion exchange membranes for bipolar ion-exchange membrane chlorine cells which protects the ion-exchange membrane from the environment. The apparatus includes a container which allows the wet membrane, or a series of membranes separated by plastic sheets to lay flat inside the container protected by a plastic sheet. The container has a roller tension bar across one end which allows each membrane to be pulled out of the container directly into the area between the anode and cathode of the cell for mounting into place.
Briefly outline the background technology and the problem the invention aims to solve.
[ "BACKGROUND OF THE INVENTION This invention relates to an apparatus and method for storing, transporting and installing a sheet-like member between two adjacent opposing planar members.", "More particularly, this invention relates to an apparatus and method for storing, transporting and installing membrane members between electrode frame members of an electrolyzer of the filter press type.", "Electrolytic cells of the filter press-type are known to be used for the electrolysis of aqueous salt solutions and have been commercially employed for the production of chlorine and caustic from brine.", "The filter press type electrolyzer for electrolysis of an aqueous salt solution commonly employ a plurality of electrolytic cell frame members or units with electrodes held thereto and assembled in a filter press type arrangement, separated from each other by membranes, diaphragms or microporous separators, forming a plurality of anolyte and catholyte compartments.", "The electrodes used in the cells are generally either monopolar or bipolar electrodes.", "Membranes typically used in the cells are generally available in sheet form and have ion exchange properties, for example, membrane materials employed in the cells are such as those marketed by E. I. duPont de Nemours and Company under the trademark NAFION and by Asahi Glass Company Ltd. under the trademark FLEMION.", "In ion-exchange membrane chlorine cells of the filter press type, some ion-exchange membranes used in the cells have to be placed between the bipolar or monopolar chlorine cell units and remain wet with salt water as long as possible until the cells begin to produce chlorine and caustic product.", "Membranes can be ruined, for example, if the membrane is exposed to the atmosphere for any great length of time and it dries out.", "A membrane can dry out in the length of time it takes to install the membrane in an electrolyzer.", "Some electrolyzers are made up of as many as 60 or more electrolytic cell units in series and therefore 60 or more of the ion-exchange membranes have to be installed between the cells.", "The membrane in sheet form is very similar to fabric, normally in a size of about 4 feet by 10 feet or 5 feet by 12 feet.", "When electrolyzers utilizing the membranes are located outdoors, the installation of the membranes within the cells would expose the membranes to dust, wind and sun.", "Previous techniques of installing the membranes included tentering the membrane by hand beside the electrolyzer and then raising the membranes up and over the electrolytic cell units.", "The membrane, when using this technique, is exposed to the outdoor environment and is lowered from the top of the cell units down between the cell units.", "Handling problems do occur due to having to raise and position the membrane over the chlorine cell units and being careful to avoid wrinkling or tearing the membrane.", "It would be desirous to provide a container which would conceal and store the membrane until the moment required for installing the membrane between the cell units to minimize the membrane being in contact with the elements such as wind and sun which could damage the membrane before it is used.", "The advantage of the present invention over the prior art methods is that the exposure of the membranes to the outdoor environment and wrinkling of the membranes is minimized when being suspended openly.", "SUMMARY OF THE INVENTION This invention is directed to a combination storage, transportation and installation container apparatus for sheet-like members such as ion exchange membranes for bipolar or monopolar ion-exchange membrane chlorine cells.", "The container includes (a) at least four side walls and a bottom and is adapted for receiving at least one sheet-like member in a substantially planar position inside the container and (b) a roller tension bar member disposed across at least two parallel side walls of the container, the tension bar member adapted for guiding a sheet-like member being removed from inside the container to a use point.", "The container protects the membrane from the environment, and maintains the membrane wet if desired.", "The container may be used to install membranes in electrolzer by pulling out of the membrane from the container directly into the area between an anode and cathode of an electrolytic cell for mounting the membrane into place.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a container of the present invention.", "FIG. 2 is a cross-sectional view taken along line 2--2 of FIG. 1 showing a container of the present invention.", "FIG. 3 is side view showing a container of the present invention being used to install a membrane in an electrolysis cell.", "FIG. 4 is a fragmentary side view showing another embodiment of a roller tension bar in a container of the present invention.", "FIG. 5 is a side view taken along line 5--5 of FIG. 4 showing the roller tension bar of FIG. 4. FIG. 6 is a top view of the roller tension bar of FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIGS. 1 and 2, there is shown a container of the present invention, generally indicated by numeral 10, with several sheet-like members 21 placed in the container 10.", "The container 10 includes four side walls 11-14 and a bottom 15.", "In this instance the container is box-like and rectangular in shape with side walls 11 and 12 parallel to each other and 13 and 14 parallel to each other.", "Other shapes of the container, such as square or circular, can be used.", "This will depend, to some extent, on the shape of the sheet-like member.", "Roller bar support members 16 on side walls 11 and 12 hold a roller tension bar member 17 extending on top of and across the length of the container 10.", "The roller tension bar 17 is adapted for guiding a sheet-like member such as a membrane 21 and keeping it planar as it exits the container 10.", "The roller tension bar 17 is preferably rotatably mounted in the container 10.", "One side of the membrane contacts the length of the roller tension bar 17 as the membrane is removed from the inside of the container 10 to a use point outside the container.", "The roller tension bar 17 preferably rotates as the membrane, for example, is pulled across the surface of the roller bar to maintain contact with the surface of one side of the membrane until it is removed from the container.", "It is preferred to place roller means generally indicated by numeral 18 on the bottom of the container 10 for ease of moving the container from one location to another.", "In this instance, the roller means 18 includes a support frame 19 with casters 20 attached to the bottom of the support frame 19.", "The container 10 is removably mounted on the support frame 19 or, if desired, the bottom wall 15 may be attached to the support frame 19.", "The roller means 18 allows the container 10 to be rolled to a use location.", "In another embodiment, the casters 20 may be attached directly to the bottom wall 15 of the container 10.", "Other means for moving the container to the location for its use can also be used such as by lifting the container with a lifting device.", "The materials of construction for the container and support frame are conventional such as metal or plastic having sufficient strength to support the handling of loads placed thereon.", "The container 10 can contain a single or plurality of sheet-like members such as membranes 21 with or without a clamping means (not shown) attached to the top edge of each membrane for ease of removing the membrane from the container.", "The membranes 21 are preferably ion-exchange membranes.", "When a plurality of electrolytic cell units are assembled in operable combination, an ion exchange membrane is positioned between adjoining electrolytic units.", "The type of ion exchange membrane used in the present invention is not critical.", "Representative of the types of ion exchange membrane suitable for use in assembling a plurality of electrolytic units are disclosed in the following U.S. Pat. Nos. 3,909,378: 4,025,405: 4,065,366;", "4,116,888;", "4,123,336: 4,126,588;", "4,151,053: 4,176,215: 4,178,218;", "4,192,725: 4,209,635: 4,212,713: 4,251,333: 4,270,996: 4,329,435: 4,330,654: 4,337,137: 4,337,211: 4,340,680;", "4,357,218;", "4,358,412: and 4,358,545.", "These patents are hereby incorporated by reference for the purpose of the membranes they disclose.", "The ion exchange membrane 21 may preferably contain sulfonic ion exchange groups, carboxylic ion exchange groups, or both sulfonic and carboxylic acid ion exchange groups.", "Optionally, the ion exchange membrane may be a bi-layer membrane having one type of ion exchange active sites in one layer and another type of ion exchange active sites in the other layer.", "The membrane may be reinforced to impair deforming during electrolysis or it may be unreinforced to maximize the electrical conductivity throughout the membrane.", "In placing the membrane in the container 10, it is preferred to lay the membranes 21 planar to each other in a layered fashion with a flexible protective sheet member 22 interposed between the membranes 21.", "Optionally, one sheet member 22 may cover the bottom of the container 10 to avoid abrasive damage to the membranes 21.", "Any material which is used for the sheet member 22 should be inert to alkaline solution used in the container 10 and non-abrasive to the membrane 21.", "The protective sheet members 22 may be made of, for example, a plastic such as polyethylene or fluorocarbon plastic such as TEFLON®.", "Preferably, a single protective sheet cover member 22 is used to cover a single membrane 21 and is positioned between the membranes for separating from each other and protecting the membranes from abrasion from each other.", "The container 10 may contain a liquid for maintaining the membrane wetted until it is used.", "The liquid may be, for example, an aqueous alkaline solution such as NaCl solution (brine), weak caustic solution and sodium carbonate solution and the like.", "The placing of the membrane 21 and protective sheet member 22 should be carried out inside an environmentally controlled handling facility such as a clean, air-conditioned or heated room to prevent exposing the membranes to the elements.", "A protective sheet member 22 is laid on top of the last membrane 21 in the container or the container is covered with a removable container top (not shown) to keep out dust and sunlight as the container is transported outdoors to a vicinity near the electrolyzer area.", "With reference to FIG. 3, there is shown an electrolyzer generally indicated as numeral 30 with a container 10 underneath the electrolyzer 30.", "Generally, the electrolyzer 30 comprises a series of electrolytic cell units 31 supported on rails 32 which in turn are supported by two stationary platens 33 and 34.", "A compressor means such as a moveable platen 35 attached to hydraulic jacks 36 and a hydraulic reservoir 37 is used to compress the electrolytic cell units 31 together in a fluid-tight arrangement.", "The container 10 may be transported to the electrolyzer 30, for example, by fork lift or the container 10 may be rolled out to the electrolyzer work area via the roller means 18.", "With the container positioned adjacent to the series of electrolytic cell units, the container 10 is then set underneath the series of electrolytic cell units by rolling the container via its roller coasters 20.", "Preferably, the coasters 20 should allow the container to be moved bi-directionally.", "Preferred filter press type electrolytic cell units for employing the present invention are bipolar or monopolar membrane cells in which the electrolytic cell units are oriented vertically as shown in FIG. 3. Suitable bipolar filter press membrane electrolytic cell units include, for example, those described in U.S. Pat. No. 4,488,946, issued Dec. 18, 1984 to Morris et al.", "Suitable filter press monopolar membrane electrolytic cells include, for example, those described in U.S. Pat. No. 4,056,458, issued Nov. 1, 1977, to G. R. Pohto et al.", "U.S. Pat. No. 4,210,516, issued July 1, 1980, to L. Mose et al.", "and U.S. Pat. No. 4,217,199, issued Aug. 12, 1980, to H. Cunningham.", "The electrolytic cell comprises an anode or a plurality of anodes and a cathode or a plurality of cathodes, and one or more gaskets of the present invention compressed together with a membrane between each anode and adjacent cathode which divides the cell into separate anode and cathode compartments.", "The electrolytic cell is equipped with means for charging electrolyte to the cell and with means for removing the products of electrolysis from the cell.", "In particular, the anode compartments of the cell are provided with means for feeding aqueous alkali metal chloride electrolyte to the cell, suitably from a common header, and with means for removing products of electrolysis from the cell.", "Similarly, the cathode compartments of the cell are provided with means for removing products of electrolysis from the cell, and optionally with means for feeding water or other fluid to the cell.", "The electrolysis process may be operated by charging electrolyte to the electrolytic cell, electrolyzing the electrolyte therein, and removing the products of electrolysis from the electrolytic cell.", "Again, with reference to FIG. 3, in a preferred embodiment of carrying out a process of the present invention, the container 10 is rolled under the series of cells 30 and positioned directly below a space between a cell-to-cell opening.", "A rope or pulling means (not shown) is then lowered down through the space created by separated cell units from overhead the cell units.", "The pulling means are held by operating personnel who are standing above the opening.", "The top edge of the first membrane 21 is attached to the pulling means.", "The pulling means is then used to pull the membrane up through the opening manually.", "As the pulling means moves upward, the membrane 21 is pulled out of the container 10 and against the underside of the roller tension bar 17.", "The protective sheet member 22 is placed between the membrane 21 and the tension bar 17.", "The membrane 21 is pulled from the container 10 until the free bottom edge can be held by hand and located properly against the bipolar cell unit.", "The cell-to-cell opening is closed up after proper positioning of the membrane against the gaskets and the cells are pressed into position by a conventional cell press means.", "The container is then repositioned, if required, underneath the next cell-to-cell opening and the process is repeated until all membranes in the container are used.", "The container is then rolled out from under the series of cells and transferred back to the handling room by forklift or casters.", "Several more membranes are laid in the container as described above with alternate layers of polyethylene and the handling process is repeated at the series site until the desired number of membranes are installed in an electrolyzer unit.", "Referring to FIGS. 4, 5 and 6, there is shown another embodiment of a roller tension bar 40 including a pipe member 41 with a pipe member 42 concentrically disposed therein.", "The pipe member 41 is wrapped around pipe member 42 and is capable of freely spinning around the pipe member 42, i.e., it is not attached to the pipe member 42, however pipe member 41 could be securely attached to pipe member 42 if desired.", "Roller means 43 are rotatably mounted on a support member 44 which is preferably attached to a bottom member 45 with casters 46.", "A container 47 is mounted on the bottom member 45.", "The roller tension bar 40 is rotatably mounted on the roller means 43.", "In operation, the membrane surface contacts the tension 40 bar which rotates on the roller means to minimize abrasion and frictional forces which may damage the membrane as it exits the container.", "A stop piece 48 prevents the tension bar 40 from sliding off the roller means 43 and maintains the tension bar 40 in position." ]
SUMMARY OF THE INVENTION The present invention relates to the construction and production of a laminated composite pipe. Thus, the present invention proposes a method of producing a laminated composite pipe by the step of coating a pipe core, defining a central channel, with a synthetic resin layer, and the features of the present invention which are worthy of special mention are that any desired ready-made pipe is utilized directly as said pipe core; that in forming a coating of a synthetic resin layer on said ready-made pipe, a resin liquid is laminated and integrally moved onto the peripheral surface thereof by gravity while said ready-made pipe is vertically lowered in the direction of its length; and, that in order to increase the binding force between the synthetic resin layer and the ready-made pipe, glass fiber or other yarn-like material is wound on the peripheral surface of the ready-made pipe. According to the method of the invention, it is possible not only to produce the intended laminated composite pipe at low cost by an extremely simple apparatus, but also to optionally change the inner diameter by simply selecting a suitable ready-made pipe. According to a preferred embodiment of the present invention, a production method is employed which consists of the steps of winding a reinforcing continuous fiber on the outer surface of a flexible pipe while lowering the pipe in the direction of its length, passing said fiber-wound flexible pipe through a hopper containing a putty-like resin which can be set at any desired time and then through a cylindrical outer mold vertically mounted to communicate with the lower end opening in said hopper, allowing said putty-like resin to descend by gravity in an annular air gap defined between said fiber-wound flexible pipe and the inner surface of said outer mold and to form a lamination molded on the fiber-wound flexible pipe, withdrawing the laminated flexible pipe from said outer mold, and winding a parting tape on the outer surface of said withdrawn laminated flexible pipe. According to such production method, there is easily obtained a conveniently usable unset flexible pipe which can be stored in a reel form until it is put to use for piping and which, when used for piping, can be caused to take the same form as a plastically bent copper pipe by simply employing a setting means such as heating with a burner after bending said flexible pipe into a desired shape. According to a further embodiment of the present invention, said flexible pipe which is unset, i.e., which can be set at any desired time, may have a foam synthetic resin layer to provide a useful unset flexible pipe having a heat insulation effect. Further, according to the present invention, a method is provided which is suitable for forming a multiple pipe having an annular outer channel besides a central channel. Specific methods and their features and merits in various preferred embodiments of the present invention as described above will be easily understood from some manners of embodying the invention to be presently described with reference to the accompanying drawings. DESCRIPTION OF THE DRAWINGS FIGS. 1 through 6 illustrate a first embodiment. FIG. 1 is an elevation partly in longitudinal section, schematically showing means for production. FIG. 2 is a plan view showing fiber winding means. FIG. 3 is a perspective view, partly broken away, of a pipe produced. FIGS. 4 through 6 are cross-sectional views of modifications of said pipe. FIGS. 7 through 9 illustrate a second embodiment. FIG. 7 is an elevation partly in longitudinal section, schematically showing means for production. FIG. 8 is a plan view showing parting tape winding means. FIG. 9 is a perspective view, partly broken away, of a pipe produced. FIGS. 10 through 13 illustrate a third embodiment. FIG. 10 is an elevation partly in longitudinal section schematically showing means for production. FIG. 11 is a perspective view partly broken away showing a foam synthetic resin layer molding portion. FIG. 12 is a plan view of said portion. FIG. 13 is a side view, partly broken away, of a pipe produced. FIGS. 14 through 23 illustrate a fourth embodiment. FIG. 14 is an elevation partly in longitudinal section schematically showing means for production. FIG. 15 is a plan view showing projection-equipped tape winding means. FIG. 16 is a side view, partly broken away, of a pipe produced. FIG. 17 is a cross-sectional view of said pipe. FIGS. 18 through 21 are longitudinal sections showing various examples of the projection-equipped tape. FIGS. 22 and 23 are explanatory views showing how to use the tape shown in FIG. 21. DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment The first embodiment of the present invention will now be described with reference to FIGS. 1 through 6. As shown in FIG. 1, a pipe 1 is lowered in the direction of its length. This pipe 1 is a rigid linear pipe made of synthetic resin or iron, such pipe lengths being connected together by joint members 2 in such manner as to seal the interior of each pipe length. The pipe is lowered at a constant speed in a vertical descending path 5 by means of synchronously rotating feed rolls 3 and drawing rolls 4. At the initial end (upper end) of the vertical descending path 5, continuous fibers 6 are wound on the outer surface la of the pipe l. The continuous fibers are string-like bodies formed of glass fiber or the like. As shown in FIG. 2, they consist of continuous fibers 6 for counter-clockwise winding arranged in a roll form on a counter-clockwise rotary plate 8 formed with a central opening 7 allowing the passage of said pipe therethrough, and continuous fibers 6 for clockwise winding similarly arranged on a clockwise rotary plate 9 fitted over said counter-clockwise rotary plate 8. By rotating the two rotary plates 8 and 9 by any suitable means, the continuous fibers are wound on the outer pipe surface la in a mesh form to form a fiber-wound pipe 10. The fiber-wound pipe 10 is then passed (lowered) through a hopper 12 containing a putty-like resin II which can be set at any desired time and then through an outer mold 14 communicating with the lower end opening 12a in the hopper 12, suspendedly fitted over said vertical descending path 5 and defining an annular air gap 13 between it and said fiber-wound pipe 10. The putty-like resin II consists, e.g., of putty-like polyester and is continuously or intermittently fed to said hopper 12 by any suitable means. The putty-like resin II descends by gravity in said annular air gap 13 and sufficiently impregnates the layer of said continuous fibers 6 to form a resin layer around the periphery of said fiber-wound pipe 10. While the laminated pipe 15 is descending in the annular air gap, the putty-like resin II thereon is gradually set by setting means 16 arranged outside the outer mold 14. As for such setting means 16, a cooling system is employed when the putty-like resin is thermoplastic, but when it is thermosetting, a heating system is employed. The set laminated pipe 17 is withdrawn from said outer mold 14 and severed at the position of the joint member 2 to assume the form shown in FIG. 3. The continuous fibers 6 are wound on the outer pipe surface la, but by changing the width of the annular air gap 13, it is possible to form a thick resin layer 18 on the exterior of the continuous fibers 6 as shown in FIG. 3 or a thin resin layer 19 of approximately the same thickness as the fiber layer as shown in FIG. 4. Further, by providing a plurality of winding means for continuous fibers 6, it is possible to form a plurality of fiber layers as shown in FIG. 5. As can be understood from what has been described so far, the thickness of the set laminated pipe 17 can be freely changed, and by changing the diameter of the pipe, it is possible to obtain set laminated pipes 17 having various inner diameters. Further, by using a pipe 1 and outer mold 14 having a different cross-sectional shape, it is possible to produce a set laminated pipe having a corresponding cross-sectional shape, e.g., a square set laminated pipe 20, as shown in FIG. 6. By arranging the hopper 12 in a sealed chamber and applying pressure, the gravitation descent action can be promoted, and by increasing the pressure it is possible to decrease the overall height of the apparatus and to improve defoaming and impregnation of fiber layers. According to the present invention described with reference to the above embodiment, the putty-like resin II is firmly laminated on and joined to the outer pipe surface 1a through the layer of continuous fibers 6 wound on the outer surface 1a of the pipe 1, and the method is particularly effective to produce a laminated pipe of dissimilar materials wherein a pipe 1 and a putty-like resin 11 are laminated together. Further, since the lamination molding makes use of gravity acting on the putty-like resin 11, the resin density can be increased during the descending movement. Moreover, impregnation of the layer of continuous fibers 6 with putty-like resin can be satisfactorily effected deep to the outer pipe surface 1a. Further, this coupled with the fact that the pipe 1 can be used as an inner mold, simplifies the apparatus necessary for employing the method. Second Embodiment A second embodiment will now be described with reference to FIGS. 7 through 9. A flexible pipe 30 is lowered in the direction of its length. The flexible pipe 30 is wound in advance on a feed reel 31 and passes through a vertical descending path 34 as guided by a pair of upper and lower rolls 32 and 33 and reaches a take-up reel 35. The descending movement is carried out at a constant speed by the synchronous rotation of the reels 31 and 35 and drawing rolls 36. At the initial end (upper end) of the vertical descending path 34, reinforcing continuous fibers 37 are wound on the outer surface 30a of said flexible pipe 30. The reinforcing continuous fibers 37 are string-like bodies formed of glass fiber or the like and are wound in a mesh form on the outer surface 30a of the flexible pipe by the same device 38 as that shown in FIGS. 1 and 2 in the first embodiment, whereby a fiber-wound flexible pipe 39 is formed. The fiber-wound flexible pipe 39 is then passed (lowered) through a hopper 41 containing a putty-like resin 40 which can be set at any desired time and then through a cylindrical outer mold 43 communicating with the lower end opening 41a in the hopper 41, suspendedly fitted over the vertical descending path 34 and defining an annular air gap 42 between it and said fiber-wound flexible pipe 39. The putty-like resin 40 consists, e.g., of putty-like polyester and is continuously or intermittently fed to said hopper 41 by any suitable means. The putty-like resin 40 descends by gravity in said annular air gap 42, and since the fiber-wound flexible pipe 39 serves as an inner mold, the putty-like resin, while being made denser, sufficiently impregnates the layer of said reinforcing continuous fibers 37 to form a resin layer 49 on the outer surface 30a of the flexible pipe. Parting tapes 45 are then wound on the laminated flexible pipe 44 being withdrawn, thereby forming the composite pipe 48 shown in FIG. 9. Third Embodiment A third embodiment will now be described with reference to FIGS. 10 through 13. In this embodiment, the processing steps in the second embodiment up to the point where a laminated flexible pipe 44 in the second embodiment is formed are applied as such; therefore, description of the steps up to the formation of a laminated flexible pipe 44 will be omitted and the same reference characters as used in the description of the second embodiment will be used intact. While a laminated flexible pipe 44 formed in the same manner as in the second embodiment and withdrawn from the cylindrical outer mold 43 is passed through a second outer mold 50 fitted over said vertical descending path 34, a foam resin liquid 53 which can be set any desired time is fed into an annular air gap 52 between the outer surface of said laminated flexible pipe and the surface of a parting tape 51 fed to the inner surface 50a of said mold. The parting tape is preferably a film of cellophane, vinyl chloride, polyethylene, polypropylene, styrol, acrylics or nylon, and is drawn flat from a reel 54 on which it has been wound in advance. As shown in FIGS. 11 and 12, while the tape is guided by a guide plate 55, it is deformed into a cylinder with the right and left edges thereof gradually brought close to each other, whereupon it is fed onto the inner surface 50a of said outer mold. THe foam resin liquid 53 is preferably in the form of urethane, phenol, silicone, polyethylene, cellulose, urea, epoxy polyester, polystyrene, vinyl cholride or polyvinyl alcohol. For example, if it is urethane, it is in the form of a mixed liquid consisting of a P liquid 53a from a P liquid supply pipe 56 and an R liquid 53b from an R liquid supply pipe 57. While allowing the resin liquid 53 fed into said annular air space 52 to descend by gravity, a foam resin layer 58 which can be set at any desired time is formed by soft foaming on the basis of its two-liquid foaming action. At this time, since said laminated pipe 44 serves as an inner mold, the inner side of the foam resin layer 58 sticks to the outer of said putty-like resin layer 49, while the outer side sticks to and presses the parting tape 51 against the inner surface 50a of the outer mold. Further, the width of the parting tape 51 is so determined that the right and left edges thereof may overlap each other after the foaming operation. Thus, an unset composite flexible pipe 59 which is laminated pipe consisting of a flexible pipe 30, a putty-like resin layer 49 having a layer of fibers 37 embedded therein, a foam resin layer 58, and a layer of a parting tape 51, as shown in FIG. 13, and which can be set at any desired time, is continuously drawn. As shown in FIG. 10, this unset composite flexible pipe 59 is given a drawing force by the drawing rolls 36 and reaches the take-up reel 35. According to this embodiment, a composite pipe can be easily obtained which has a foam resin layer providing a heat insulation effect and which, after being deformed into any desired shape, can be used as a rigid pipe by being set in that deformed shape. In addition, the foam resin layer may be embodied by suitably selecting a material so that it remains soft, unaffected by the subsequent setting means, such setting means being effective to set the inner putty-like resin layer 49 alone. Fourth Embodiment A fourth embodiment will now be described with reference to FIGS. 14 through 23. In this embodiment, the steps up to the formation of a laminated flexible pipe 44 in the second embodiment are applied as such. Therefore, the description up to that step will be omitted and the same reference characters as used in the description of the second embodiment are also applied to these Figures. While a laminated flexible pipe 44 formed in the same manner as in the second embodiment and drawn from the cylindrical outer mold 43 is lowered in the direction of its length along said vertical descending path 34, intermediate tapes 60 are first wound on the outer surface 44a of said laminated flexible pipe. Such intermediate tape 60 is a strong one, consisting preferably of cellophane or nylon, and is spirally wound on the outer surface 42a of the flexible pipe by the same device 61 as that used for winding the parting tape 45 shown in the second exbodiment. A tape 63 having spacer projections 62 is wound on the exterior of said intermediate tapes 60. As shown in FIG. 15, such tape 60 is a strong one, consisting preferably of cellophane or nylon, and it has a number of said projections 62 erected in advance on the inner surface thereof and is supported in a roll form on a rotary plate 64. Thus, by rotating the rotary plate 64 around the axis of the laminated flexible pipe 44, the tape 63 is spirally wound on the descending laminated flexible pipe 44 in such a manner that the front ends of said projections abut against the intermediate tapes 60. As shown in FIG. 14, reinforcing continuous fibers 65 are wound in a mesh form on the outer surface of said tape 63 by the same device 66 as that shown in the second embodiment. The composite pipe is then passed (lowered) through a hopper 68 containing a putty-like resin 67 which can be set at any desired time and then through a second cylindrical outer mold 70 suspendedly fitted over said vertical descending path 34 so as to communicate with the lower end opening in said hopper 68 and to define an annular air gap 69 between it and said tape 63. The putty-like resin 67, as in the previous case, consists of putty-like polyester or the like. When it descends by gravity in said annular air gap 69, the side of said tape 63 serves as an inner mold. For this reason, the putty-like resin 67, while being compacted, sufficiently penetrates the layer of said fibers 65 to form a second resin layer 71 extending to the outer surface of the tape 63. A parting tape 72 is then wound on the outer surface of said second putty-like resin layer 71. The parting tape 72 is wound by the same device 73 as that shown in the second embodiment. As a result, an unset multiple pipe 76 is formed which, as shown in FIGS. 16 and 17, consists of a flexible pipe 30 defining an inner channel 74, a first putty-like resin layer 49 having a layer of fibers 37 embedded therein, a layer of tape 63 defining an outer channel 75 whose distance is maintained by projections 62, and a second putty-like resin layer 71 having a layer of a parting tape 72 embedded therein and which can be set at any desired time. This pipe 76 can be continuously drawn and wound onto the take-up reel 35. The reference character 36 designates drawing and guiding rolls. As for the tape 63 having projections 62 in the above embodiment, it may be in the form of a tape 63a having a number of bar-like projections 62a arranged lengthwise and widthwise, as shown in FIG. 18. Besides this, the following tapes may be used. * A tape 63b, shown in FIG. 19, having projections 62b provided with bulges 77 at their front ends. * A tape 63c, shown in FIG. 20, comprising two front and back tape elements 78a and 78b and projections 62c bridging the distance therebetween. In this case, the step of winding the intermediate tapes 60 may be omitted. * A tape 63d, shown in FIG. 21, wherein the opposite ends 79a and 79b of projections 62d extend through tape elements 79a and 79b. In this case, as shown in FIG. 22, the opposite ends 79a and 79b are thrust into the putty-like resin layers 49 and 71 to make firmer the molding between the putty-like resin layers and the tape 60d. Further, even when the tape elements 78a and 78b are such that they will melt away upon heating for the setting of the pipe, the set resin layers 49 and 71 serve to fix the ends of the projections 62d so that the distance between the resin layers is maintained. As for projections 62, it is preferable to use aluminum or copper ones, but this may be suitably changed according to the material which flows through the outer channel 75 during the use of the pipe. Further, by making an arrangement so that after the pipe is withdrawn from the second outer mold 70 it is passed again to a step of winding of a tape 63, it is possible to produce an unset multiple pipe having a plurality of outer channels similar to the one shown at 75. According to the present invention described in this embodiment, it is possible to continuously produce an unset multiple pipe which has an inner channel 74 defined by a flexible pipe 30 and an outer channel 75 defined by spacer projections 62 and which can be set at any desired time. In addition, in any of the second to fourth embodiments, it is possible, as in the first embodiment, to optionally select a thickness for each layer, inner and outer diameters for the entire pipe and a cross-sectional shape therefor. By arranging said hoppers 12, 41 and 68 in a sealed chamber and pressurizing them, the gravity descending action can be assisted, and by increasing the pressure the height of the apparatus can be decreased and, moreover, defoaming from the resin layer and penetration into fiber layers can be further improved. Further, if the hoppers 12, 31 and 68 are modified to the sealed chamber type and such chamber is constantly evacuated by a vacuum pump to provide a vacuum chamber and the cylindrical outer molds 14, 43 and 70 are increased in length to the extent that the gravity which acts on the putty-like resin injected into the vacuum chamber and tending to flow down the hopper under its own weight is balanced by the vacuum force, then this results in a degassed resin liquid impregnating the fiber laayer, providing the same merit as in the case of the pressure gravity type described above. Further, when said flexible pipe 30 is formed of cellophane or nylon and has a thin wall having the danger of being easily deformed by the fiber winding force or external pressure caused by the putty-like resin, it is possible to cope with such deformation by applying a pressure such as compressed air to the interior of the flexible pipe 30. The unset composite flexible pipe is used by optionally deforming and then setting the same by applying setting means such as heating, but at this time it is possible to use tapes formed of a thermoplastic resin film as the parting tapes 45, 51 and 72 so that they may be automatically melted away.
A laminated composite pipe is produced by employing a pre-formed pipe as a core and applying a layer of reinforcing fiber onto the outer surface of the pipe core which is being lowered vertically in the direction of its length through a hopper and a tubular outer mold. Resin supplied to the hopper is drawn into an annular space between the wound pipe and the outer mold and forms a layer on the wound pipe core. A flexible pipe may be used as the core, together with a resin that can be subsequently cured, thereby forming a flexible laminated composite pipe which can be covered with a parting tape, stored in reel form, and given a permanent set after installation by curing the resin. Depending upon the nature of the resin employed and upon the number of resin layers applied to the pipe core, reinforcing, insulating and stiffening properties, or any combination of such properties, may be imparted to the composite pipe. A multi-channel pipe may be formed by the application to one of the composite pipes described above of an additional tape provided with spacer projections, followed by the application of reinforcing fiber and resin.
Concisely explain the essential features and purpose of the invention.
[ "SUMMARY OF THE INVENTION The present invention relates to the construction and production of a laminated composite pipe.", "Thus, the present invention proposes a method of producing a laminated composite pipe by the step of coating a pipe core, defining a central channel, with a synthetic resin layer, and the features of the present invention which are worthy of special mention are that any desired ready-made pipe is utilized directly as said pipe core;", "that in forming a coating of a synthetic resin layer on said ready-made pipe, a resin liquid is laminated and integrally moved onto the peripheral surface thereof by gravity while said ready-made pipe is vertically lowered in the direction of its length;", "and, that in order to increase the binding force between the synthetic resin layer and the ready-made pipe, glass fiber or other yarn-like material is wound on the peripheral surface of the ready-made pipe.", "According to the method of the invention, it is possible not only to produce the intended laminated composite pipe at low cost by an extremely simple apparatus, but also to optionally change the inner diameter by simply selecting a suitable ready-made pipe.", "According to a preferred embodiment of the present invention, a production method is employed which consists of the steps of winding a reinforcing continuous fiber on the outer surface of a flexible pipe while lowering the pipe in the direction of its length, passing said fiber-wound flexible pipe through a hopper containing a putty-like resin which can be set at any desired time and then through a cylindrical outer mold vertically mounted to communicate with the lower end opening in said hopper, allowing said putty-like resin to descend by gravity in an annular air gap defined between said fiber-wound flexible pipe and the inner surface of said outer mold and to form a lamination molded on the fiber-wound flexible pipe, withdrawing the laminated flexible pipe from said outer mold, and winding a parting tape on the outer surface of said withdrawn laminated flexible pipe.", "According to such production method, there is easily obtained a conveniently usable unset flexible pipe which can be stored in a reel form until it is put to use for piping and which, when used for piping, can be caused to take the same form as a plastically bent copper pipe by simply employing a setting means such as heating with a burner after bending said flexible pipe into a desired shape.", "According to a further embodiment of the present invention, said flexible pipe which is unset, i.e., which can be set at any desired time, may have a foam synthetic resin layer to provide a useful unset flexible pipe having a heat insulation effect.", "Further, according to the present invention, a method is provided which is suitable for forming a multiple pipe having an annular outer channel besides a central channel.", "Specific methods and their features and merits in various preferred embodiments of the present invention as described above will be easily understood from some manners of embodying the invention to be presently described with reference to the accompanying drawings.", "DESCRIPTION OF THE DRAWINGS FIGS. 1 through 6 illustrate a first embodiment.", "FIG. 1 is an elevation partly in longitudinal section, schematically showing means for production.", "FIG. 2 is a plan view showing fiber winding means.", "FIG. 3 is a perspective view, partly broken away, of a pipe produced.", "FIGS. 4 through 6 are cross-sectional views of modifications of said pipe.", "FIGS. 7 through 9 illustrate a second embodiment.", "FIG. 7 is an elevation partly in longitudinal section, schematically showing means for production.", "FIG. 8 is a plan view showing parting tape winding means.", "FIG. 9 is a perspective view, partly broken away, of a pipe produced.", "FIGS. 10 through 13 illustrate a third embodiment.", "FIG. 10 is an elevation partly in longitudinal section schematically showing means for production.", "FIG. 11 is a perspective view partly broken away showing a foam synthetic resin layer molding portion.", "FIG. 12 is a plan view of said portion.", "FIG. 13 is a side view, partly broken away, of a pipe produced.", "FIGS. 14 through 23 illustrate a fourth embodiment.", "FIG. 14 is an elevation partly in longitudinal section schematically showing means for production.", "FIG. 15 is a plan view showing projection-equipped tape winding means.", "FIG. 16 is a side view, partly broken away, of a pipe produced.", "FIG. 17 is a cross-sectional view of said pipe.", "FIGS. 18 through 21 are longitudinal sections showing various examples of the projection-equipped tape.", "FIGS. 22 and 23 are explanatory views showing how to use the tape shown in FIG. 21.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment The first embodiment of the present invention will now be described with reference to FIGS. 1 through 6.", "As shown in FIG. 1, a pipe 1 is lowered in the direction of its length.", "This pipe 1 is a rigid linear pipe made of synthetic resin or iron, such pipe lengths being connected together by joint members 2 in such manner as to seal the interior of each pipe length.", "The pipe is lowered at a constant speed in a vertical descending path 5 by means of synchronously rotating feed rolls 3 and drawing rolls 4.", "At the initial end (upper end) of the vertical descending path 5, continuous fibers 6 are wound on the outer surface la of the pipe l. The continuous fibers are string-like bodies formed of glass fiber or the like.", "As shown in FIG. 2, they consist of continuous fibers 6 for counter-clockwise winding arranged in a roll form on a counter-clockwise rotary plate 8 formed with a central opening 7 allowing the passage of said pipe therethrough, and continuous fibers 6 for clockwise winding similarly arranged on a clockwise rotary plate 9 fitted over said counter-clockwise rotary plate 8.", "By rotating the two rotary plates 8 and 9 by any suitable means, the continuous fibers are wound on the outer pipe surface la in a mesh form to form a fiber-wound pipe 10.", "The fiber-wound pipe 10 is then passed (lowered) through a hopper 12 containing a putty-like resin II which can be set at any desired time and then through an outer mold 14 communicating with the lower end opening 12a in the hopper 12, suspendedly fitted over said vertical descending path 5 and defining an annular air gap 13 between it and said fiber-wound pipe 10.", "The putty-like resin II consists, e.g., of putty-like polyester and is continuously or intermittently fed to said hopper 12 by any suitable means.", "The putty-like resin II descends by gravity in said annular air gap 13 and sufficiently impregnates the layer of said continuous fibers 6 to form a resin layer around the periphery of said fiber-wound pipe 10.", "While the laminated pipe 15 is descending in the annular air gap, the putty-like resin II thereon is gradually set by setting means 16 arranged outside the outer mold 14.", "As for such setting means 16, a cooling system is employed when the putty-like resin is thermoplastic, but when it is thermosetting, a heating system is employed.", "The set laminated pipe 17 is withdrawn from said outer mold 14 and severed at the position of the joint member 2 to assume the form shown in FIG. 3. The continuous fibers 6 are wound on the outer pipe surface la, but by changing the width of the annular air gap 13, it is possible to form a thick resin layer 18 on the exterior of the continuous fibers 6 as shown in FIG. 3 or a thin resin layer 19 of approximately the same thickness as the fiber layer as shown in FIG. 4. Further, by providing a plurality of winding means for continuous fibers 6, it is possible to form a plurality of fiber layers as shown in FIG. 5. As can be understood from what has been described so far, the thickness of the set laminated pipe 17 can be freely changed, and by changing the diameter of the pipe, it is possible to obtain set laminated pipes 17 having various inner diameters.", "Further, by using a pipe 1 and outer mold 14 having a different cross-sectional shape, it is possible to produce a set laminated pipe having a corresponding cross-sectional shape, e.g., a square set laminated pipe 20, as shown in FIG. 6. By arranging the hopper 12 in a sealed chamber and applying pressure, the gravitation descent action can be promoted, and by increasing the pressure it is possible to decrease the overall height of the apparatus and to improve defoaming and impregnation of fiber layers.", "According to the present invention described with reference to the above embodiment, the putty-like resin II is firmly laminated on and joined to the outer pipe surface 1a through the layer of continuous fibers 6 wound on the outer surface 1a of the pipe 1, and the method is particularly effective to produce a laminated pipe of dissimilar materials wherein a pipe 1 and a putty-like resin 11 are laminated together.", "Further, since the lamination molding makes use of gravity acting on the putty-like resin 11, the resin density can be increased during the descending movement.", "Moreover, impregnation of the layer of continuous fibers 6 with putty-like resin can be satisfactorily effected deep to the outer pipe surface 1a.", "Further, this coupled with the fact that the pipe 1 can be used as an inner mold, simplifies the apparatus necessary for employing the method.", "Second Embodiment A second embodiment will now be described with reference to FIGS. 7 through 9.", "A flexible pipe 30 is lowered in the direction of its length.", "The flexible pipe 30 is wound in advance on a feed reel 31 and passes through a vertical descending path 34 as guided by a pair of upper and lower rolls 32 and 33 and reaches a take-up reel 35.", "The descending movement is carried out at a constant speed by the synchronous rotation of the reels 31 and 35 and drawing rolls 36.", "At the initial end (upper end) of the vertical descending path 34, reinforcing continuous fibers 37 are wound on the outer surface 30a of said flexible pipe 30.", "The reinforcing continuous fibers 37 are string-like bodies formed of glass fiber or the like and are wound in a mesh form on the outer surface 30a of the flexible pipe by the same device 38 as that shown in FIGS. 1 and 2 in the first embodiment, whereby a fiber-wound flexible pipe 39 is formed.", "The fiber-wound flexible pipe 39 is then passed (lowered) through a hopper 41 containing a putty-like resin 40 which can be set at any desired time and then through a cylindrical outer mold 43 communicating with the lower end opening 41a in the hopper 41, suspendedly fitted over the vertical descending path 34 and defining an annular air gap 42 between it and said fiber-wound flexible pipe 39.", "The putty-like resin 40 consists, e.g., of putty-like polyester and is continuously or intermittently fed to said hopper 41 by any suitable means.", "The putty-like resin 40 descends by gravity in said annular air gap 42, and since the fiber-wound flexible pipe 39 serves as an inner mold, the putty-like resin, while being made denser, sufficiently impregnates the layer of said reinforcing continuous fibers 37 to form a resin layer 49 on the outer surface 30a of the flexible pipe.", "Parting tapes 45 are then wound on the laminated flexible pipe 44 being withdrawn, thereby forming the composite pipe 48 shown in FIG. 9. Third Embodiment A third embodiment will now be described with reference to FIGS. 10 through 13.", "In this embodiment, the processing steps in the second embodiment up to the point where a laminated flexible pipe 44 in the second embodiment is formed are applied as such;", "therefore, description of the steps up to the formation of a laminated flexible pipe 44 will be omitted and the same reference characters as used in the description of the second embodiment will be used intact.", "While a laminated flexible pipe 44 formed in the same manner as in the second embodiment and withdrawn from the cylindrical outer mold 43 is passed through a second outer mold 50 fitted over said vertical descending path 34, a foam resin liquid 53 which can be set any desired time is fed into an annular air gap 52 between the outer surface of said laminated flexible pipe and the surface of a parting tape 51 fed to the inner surface 50a of said mold.", "The parting tape is preferably a film of cellophane, vinyl chloride, polyethylene, polypropylene, styrol, acrylics or nylon, and is drawn flat from a reel 54 on which it has been wound in advance.", "As shown in FIGS. 11 and 12, while the tape is guided by a guide plate 55, it is deformed into a cylinder with the right and left edges thereof gradually brought close to each other, whereupon it is fed onto the inner surface 50a of said outer mold.", "THe foam resin liquid 53 is preferably in the form of urethane, phenol, silicone, polyethylene, cellulose, urea, epoxy polyester, polystyrene, vinyl cholride or polyvinyl alcohol.", "For example, if it is urethane, it is in the form of a mixed liquid consisting of a P liquid 53a from a P liquid supply pipe 56 and an R liquid 53b from an R liquid supply pipe 57.", "While allowing the resin liquid 53 fed into said annular air space 52 to descend by gravity, a foam resin layer 58 which can be set at any desired time is formed by soft foaming on the basis of its two-liquid foaming action.", "At this time, since said laminated pipe 44 serves as an inner mold, the inner side of the foam resin layer 58 sticks to the outer of said putty-like resin layer 49, while the outer side sticks to and presses the parting tape 51 against the inner surface 50a of the outer mold.", "Further, the width of the parting tape 51 is so determined that the right and left edges thereof may overlap each other after the foaming operation.", "Thus, an unset composite flexible pipe 59 which is laminated pipe consisting of a flexible pipe 30, a putty-like resin layer 49 having a layer of fibers 37 embedded therein, a foam resin layer 58, and a layer of a parting tape 51, as shown in FIG. 13, and which can be set at any desired time, is continuously drawn.", "As shown in FIG. 10, this unset composite flexible pipe 59 is given a drawing force by the drawing rolls 36 and reaches the take-up reel 35.", "According to this embodiment, a composite pipe can be easily obtained which has a foam resin layer providing a heat insulation effect and which, after being deformed into any desired shape, can be used as a rigid pipe by being set in that deformed shape.", "In addition, the foam resin layer may be embodied by suitably selecting a material so that it remains soft, unaffected by the subsequent setting means, such setting means being effective to set the inner putty-like resin layer 49 alone.", "Fourth Embodiment A fourth embodiment will now be described with reference to FIGS. 14 through 23.", "In this embodiment, the steps up to the formation of a laminated flexible pipe 44 in the second embodiment are applied as such.", "Therefore, the description up to that step will be omitted and the same reference characters as used in the description of the second embodiment are also applied to these Figures.", "While a laminated flexible pipe 44 formed in the same manner as in the second embodiment and drawn from the cylindrical outer mold 43 is lowered in the direction of its length along said vertical descending path 34, intermediate tapes 60 are first wound on the outer surface 44a of said laminated flexible pipe.", "Such intermediate tape 60 is a strong one, consisting preferably of cellophane or nylon, and is spirally wound on the outer surface 42a of the flexible pipe by the same device 61 as that used for winding the parting tape 45 shown in the second exbodiment.", "A tape 63 having spacer projections 62 is wound on the exterior of said intermediate tapes 60.", "As shown in FIG. 15, such tape 60 is a strong one, consisting preferably of cellophane or nylon, and it has a number of said projections 62 erected in advance on the inner surface thereof and is supported in a roll form on a rotary plate 64.", "Thus, by rotating the rotary plate 64 around the axis of the laminated flexible pipe 44, the tape 63 is spirally wound on the descending laminated flexible pipe 44 in such a manner that the front ends of said projections abut against the intermediate tapes 60.", "As shown in FIG. 14, reinforcing continuous fibers 65 are wound in a mesh form on the outer surface of said tape 63 by the same device 66 as that shown in the second embodiment.", "The composite pipe is then passed (lowered) through a hopper 68 containing a putty-like resin 67 which can be set at any desired time and then through a second cylindrical outer mold 70 suspendedly fitted over said vertical descending path 34 so as to communicate with the lower end opening in said hopper 68 and to define an annular air gap 69 between it and said tape 63.", "The putty-like resin 67, as in the previous case, consists of putty-like polyester or the like.", "When it descends by gravity in said annular air gap 69, the side of said tape 63 serves as an inner mold.", "For this reason, the putty-like resin 67, while being compacted, sufficiently penetrates the layer of said fibers 65 to form a second resin layer 71 extending to the outer surface of the tape 63.", "A parting tape 72 is then wound on the outer surface of said second putty-like resin layer 71.", "The parting tape 72 is wound by the same device 73 as that shown in the second embodiment.", "As a result, an unset multiple pipe 76 is formed which, as shown in FIGS. 16 and 17, consists of a flexible pipe 30 defining an inner channel 74, a first putty-like resin layer 49 having a layer of fibers 37 embedded therein, a layer of tape 63 defining an outer channel 75 whose distance is maintained by projections 62, and a second putty-like resin layer 71 having a layer of a parting tape 72 embedded therein and which can be set at any desired time.", "This pipe 76 can be continuously drawn and wound onto the take-up reel 35.", "The reference character 36 designates drawing and guiding rolls.", "As for the tape 63 having projections 62 in the above embodiment, it may be in the form of a tape 63a having a number of bar-like projections 62a arranged lengthwise and widthwise, as shown in FIG. 18.", "Besides this, the following tapes may be used.", "* A tape 63b, shown in FIG. 19, having projections 62b provided with bulges 77 at their front ends.", "* A tape 63c, shown in FIG. 20, comprising two front and back tape elements 78a and 78b and projections 62c bridging the distance therebetween.", "In this case, the step of winding the intermediate tapes 60 may be omitted.", "* A tape 63d, shown in FIG. 21, wherein the opposite ends 79a and 79b of projections 62d extend through tape elements 79a and 79b.", "In this case, as shown in FIG. 22, the opposite ends 79a and 79b are thrust into the putty-like resin layers 49 and 71 to make firmer the molding between the putty-like resin layers and the tape 60d.", "Further, even when the tape elements 78a and 78b are such that they will melt away upon heating for the setting of the pipe, the set resin layers 49 and 71 serve to fix the ends of the projections 62d so that the distance between the resin layers is maintained.", "As for projections 62, it is preferable to use aluminum or copper ones, but this may be suitably changed according to the material which flows through the outer channel 75 during the use of the pipe.", "Further, by making an arrangement so that after the pipe is withdrawn from the second outer mold 70 it is passed again to a step of winding of a tape 63, it is possible to produce an unset multiple pipe having a plurality of outer channels similar to the one shown at 75.", "According to the present invention described in this embodiment, it is possible to continuously produce an unset multiple pipe which has an inner channel 74 defined by a flexible pipe 30 and an outer channel 75 defined by spacer projections 62 and which can be set at any desired time.", "In addition, in any of the second to fourth embodiments, it is possible, as in the first embodiment, to optionally select a thickness for each layer, inner and outer diameters for the entire pipe and a cross-sectional shape therefor.", "By arranging said hoppers 12, 41 and 68 in a sealed chamber and pressurizing them, the gravity descending action can be assisted, and by increasing the pressure the height of the apparatus can be decreased and, moreover, defoaming from the resin layer and penetration into fiber layers can be further improved.", "Further, if the hoppers 12, 31 and 68 are modified to the sealed chamber type and such chamber is constantly evacuated by a vacuum pump to provide a vacuum chamber and the cylindrical outer molds 14, 43 and 70 are increased in length to the extent that the gravity which acts on the putty-like resin injected into the vacuum chamber and tending to flow down the hopper under its own weight is balanced by the vacuum force, then this results in a degassed resin liquid impregnating the fiber laayer, providing the same merit as in the case of the pressure gravity type described above.", "Further, when said flexible pipe 30 is formed of cellophane or nylon and has a thin wall having the danger of being easily deformed by the fiber winding force or external pressure caused by the putty-like resin, it is possible to cope with such deformation by applying a pressure such as compressed air to the interior of the flexible pipe 30.", "The unset composite flexible pipe is used by optionally deforming and then setting the same by applying setting means such as heating, but at this time it is possible to use tapes formed of a thermoplastic resin film as the parting tapes 45, 51 and 72 so that they may be automatically melted away." ]
CROSS-REFERENCES TO RELATED APPLICATIONS None. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT None. THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT None. INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC None. BACKGROUND OF THE INVENTION 1. Field of the Invention The invention concerns wireless inductive lighting systems for models, decorative lighting, and communications using variable frequency power. 2. Background Art During special occasions, many families enjoy setting model displays on mantels or around Christmas trees, such as 18th century villages and manger scenes. The village is made up of multiple building models all with their own light source. Each building is positioned and their light source is connected to a power strip to give the buildings their power. All the power cables are then hidden carefully under a white fabric resembling snow. There are many problems with this system. Once the models are positioned and their power cables are connected, it is very time intensive to reposition the models. This requires unplugging the power cable, moving the model, plugging in the power cable and hiding the cable. Also, the large number of power cables all connecting to a single outlet presents a fire hazard as well as risks tripping a circuit breaker. Additionally, efforts to hide all of the power cables are time consuming and is seldom aesthetically pleasing. Lastly, when these models are removed at the end of the season, the large number of power cords make storing the Christmas village very cumbersome. One approach to lessen the difficulty is to use battery-powered lighting. However, these devices often experience battery acid leakage and corrosion while in long-term storage between device usage. These displays would benefit greatly by a method of lighting the models that did not involve a power cord for every lighted model or batteries. The invention herein described uses inductive power provided by a first winding in a mat, delivered to second windings that are part of the model(s) to be lit. Use of inductive power is well known in electrical engineering; Nikola Tesla first demonstrated such power transfer in the late 19th century. Many systems exist to charge batteries and other devices. However, recent products are seeking to use contactless power transfer, often to charge a mobile phone or other battery-powered device by sitting it on a recharging mat. A primary coil in the mat creates a time varying magnetic field that interacts with and delivers power to a secondary coil in the device to be charged. A popular development group for near field inductive power is the Wireless Power Consortium (“WPC”), formed in 2008 to assist companies developing products. The WPC specification, developed less than two years later, defines its own operating parameters to transfer upwards of 5 W using ac frequencies of 100 to 205 kHz, and includes communications between the mat and device being charged. The WPC specification is fairly complex, detailing control signals to actuate a primary coil that interacts with a secondary coil in a device to be powered and a digital logic control communication protocol. The Consortium's specification also includes a definition of a primary coil that is specific in width (40 mm) and thickness (2mm), among other details of construction, including wire gage, shielding, etc. It is aimed at charging an expensive cell phone, and not appropriate for inexpensive lighting systems that are inherently capable of operation under a wide range of electrical conditions. What is needed is a lighting system designed to provide power by induction to inexpensive lighting devices. BRIEF SUMMARY OF THE INVENTION The invention shown in FIG. 1 is an induction-based Lighting System 11 designed to provide power to model displays and other similar applications. The first part of the system is the wireless Power Mat 13 that is placed under the model houses and used as the base for the village. The Power Mat 13 replaces the decorative cloth or felt base typically used as the base for the village. The Mat 13 is powered from a standard AC wall adapter or batteries and generates a time-varying magnetic field to inductively power lights through a secondary winding. Mats can be different sizes to suit the avid Christmas decorator along with individuals looking to set up their model quickly. The Lighting System uses a small wireless illumination “Tag” 17 that can fit inside the models with a light-emitted diode (“LED”) and other basic circuitry, including a secondary winding that interacts with the mat. This Tag 17 replaces incandescent lights currently in the models, as well as with the power cable that is made unnecessary. Tags 17 are populated with lights of different brightness, color and blinking or flickering features. The following explanation discusses one embodiment of the invention, comprising a flexible Christmas village mat that can be rolled for easy storage, and several inductively powered lights. Other applications using the same invention are also discussed. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) FIG. 1 shows the Lighting System in use. FIG. 2A shows one embodiment of a Tag's physical construction. FIG. 2B shows one possible schematic of a Tag. FIG. 3 shows the Power Mat construction. FIG. 4 is a block diagram of one embodiment of an Advanced Mat. FIG. 5 shows a time division block diagram. FIG. 6 provides an example of time division frequency switching. FIG. 7 shows a method of varying frequencies using superposition. FIG. 8 shows a Primary Winding build from five-conductor ribbon cable. FIG. 9 shows a block diagram of one embodiment of an Auxiliary Mat. DETAILED DESCRIPTION OF THE INVENTION The invention described herein builds upon the basic inductive wireless power transfer system (specifically resonant inductive coupling) with enhancements to specifically support a wireless illumination system for models (model rail road sets, Christmas villages), games (illuminated chess sets, children's play sets with light up cars), furniture (illuminated cups in movie theatres and trendy bars, doll cases, flower vase with light up flowers, kids teapot table or table runner with light up dishes, and aquariums where waterproof Tags are located at the bottom of the aquarium), and flooring (where illuminated shoes and other items that could light up when placed in certain locations). As shown in FIG. 1 , the invention 11 comprises two essential components: a wireless Power Mat 13 and illumination Tags 17 . A Primary Winding 21 is embedded within the Mat 13 , typically not visible to users, but is represented as the inductive Primary Winding 21 in FIG. 3 . Power is transferred inductively between the Power Mat 13 and multiple Tags 17 simultaneously and Tags 17 can be designed with circuitry to blink or flicker. The Power Mat 13 supports the ability to operate on multiple frequencies using time slicing allowing it to independently control Tags 17 tuned to different frequencies. A more complex Advanced Auxiliary Mat 15 that acts in accordance with sensors and switch inputs is also described, incorporating a Light Sensor 31 to automatically activate in darkness, as well as a Timer 33 and Pushbutton 35 to allow the user to turn it on for a preset period or programmed schedule, or change the frequency with the Pushbutton 35 . Finally, a user can employ an Auxiliary Mat 19 , depicted in the electronic representation shown in FIG. 9 , which is identical to the Power Mat 13 , except that it obtains its power by reacting with the Power Mat's Primary Winding 21 . The Auxiliary Mat 19 is simply properly placed next to the Power Mat 13 . The Power Mat's Primary Winding 21 delivers power to the winding in the Auxiliary Mat 19 , which in turn, provides power to the Tags 17 placed on the Auxiliary Mat 19 . Illuminator Tags—As shown in FIGS. 2A and 2B , the Tags 17 consist of a parallel tuned LC-resonant circuit composed of the Secondary Winding 27 and Tag Capacitor 28 , typically tuned in the neighborhood of 125 kHz, and an LED 25 . The impedance of a parallel tuned resonant circuit approaches infinity at the resonant frequency, which means that the voltage induced in the Tag's Coil 27 (which is at or near the resonant frequency of the circuit) is not absorbed by the tuned circuit but is instead used by the LED 25 to provide light. The amount of energy absorbed by the Tag 17 from the Power Mat 13 is dependent on many factors including strength of the field, proximity of the Tag 17 to the Mat 13 , orientation of the Tag 17 , number of turns and size of the Tag's Coil (or Secondary Winding) 27 . Basically, the more magnetic field lines that are cut by the Tag's Secondary Winding 27 , the more energy that is extracted from the field and available to power the LED 25 and whatever other circuitry is on the Tag 17 . The most simple design uses an LED to rectify the alternating current generated in the Secondary Coil 27 of the Tag to power said LED 25 . A more complex tag design would rectify the alternating current generated by the Power Mat 13 to create lighting effects on the Tag 17 such as a flickering fire. To simplify the Tag 17 construction, the Tag's Secondary Winding 27 is etched onto a circuit Board 24 (shown in FIG. 2A ) using standard circuit board manufacturing techniques which ensures consistent performance. The LED 25 and Capacitor 28 are also soldered to the Board 24 which provides a convenient structure for the Tag 17 . Additionally, a small commercially available ferrite core inductor can be used instead of an air core coil or circuit-board etched coil allowing a more compact design in some situations. As long as the Tag 17 can be placed inside of the Power Mat's magnetic field, it will illuminate, providing a large number of possibilities in terms of applications since the magnetic field will penetrate most non-conductive materials, including plastic, wood, and glass, allowing the Tag 17 and or the Power Mat 13 to be embedded inside objects and table tops. A single Power Mat 13 can be used to power multiple Tags 17 simultaneously due to the size of the Power Mat's magnetic field. A multi-frequency mat can be used to control Tags or sets of Tags 17 tuned to different frequencies by changing the frequency or strength of the generated magnetic field for different lengths of times to independently power sets of tuned tags to create lighting effects. For example the 125 KHz Tags could be on steadily, while the 120 KHz Tags blink, and the 115 kHz Tags flicker, emulating the motion of fire. Wireless Power Mat Details—The system uses resonant inductive coupling to transfer power from the Power Mat 13 to the Tag 17 . As shown in FIG. 3 , the Power Mat is powered by a direct-current power source, and consists of an Oscillator 41 , Driver 43 , Mat Capacitor 45 , and a Primary Winding 21 which is embedded in the Power Mat 13 . The Mat Capacitor 45 and Primary Winding 21 make up a series-tuned resonant inductor-capacitor Circuit 22 designed to resonate at 125 kHz in this application. Optional Mat Connectors 23 are indicated on FIG. 1 that can be used to affix an Auxiliary Mat and hold it in place to receive power from a Power Mat 13 most efficiently; it is assumed that a practitioner in the art can design many types of connectors that would perform this function with ease. Driving the series-resonant Circuit 22 at its resonant frequency minimizes its impedance resulting in maximum current flow through the circuit which results in a maximum magnetic field strength generated by the Primary Winding 21 , providing maximum power transfer between the Power Mat 13 and Tag 17 . The size of the field is determined by the winding dimensions, the current running through the windings, and the number of turns. In this embodiment, the Primary Winding 21 consists of a 14-turn coil of 26 awg enameled copper wire that runs around the perimeter of the Power Mat 13 . Larger systems may require multiple windings, also known as coils. To create a field large enough to be useful in this application, the Primary Winding 21 runs along the perimeter of the Power Mat 13 . To date, the largest mat constructed has been 10″ by 44″, but the invention is not restricted to any particular size. Tags 17 are placed inside the perimeter of the Primary Winding 21 or just outside it to ensure they are energized. To make the mat easily stored, the Primary Winding 21 is placed between two neoprene sheets allowing it to be rolled up for storage. Current embodiments have employed hand wound windings but costs can easily be reduced in production by using a printed or foil-based coil. A mundane 12 Vdc desktop power supply provides power to the current embodiment of the Power Mat 13 , but it could be made battery-powered to support use in toys and other portable applications. Advanced Power Mat—While the term “mat” is used throughout this specification, the mat could be an actual mat, or a table top or other furniture with a coil and related electronics integrated into the top surface. FIG. 4 shows a block diagram of this Advanced Power Mat (“Advanced Mat”) 15 with the enhancements ideal for wireless illumination. The system consists of a Microcontroller 51 which controls current through the Primary Winding 21 . It interfaces with a Light Sensor 31 to control the Advanced Mat 15 in low light conditions. It incorporates a Timer 33 and Pushbutton Interface 35 to activate the Timer to allow the user to activate the invention for a programmed period of time. This feature is also useful for games. The Timer can also be used to control the mat at different times of the day. Finally, the Microcontroller 51 has an interface to connect with switches and buttons in support of integrating the invention into toys (e.g. pushing a button could make certain lights blink, dim, or turn on) The Microcontroller 51 generates the 125 kHz waveforms to drive the Primary Winding 21 by operation of a Mat Driver 53 . After the Microcontroller 51 operates the Mat Driver 53 to energize the Mat's Primary Winding 21 , Tags 17 placed on the Mat's surface will illuminate. In addition to generating a steady 125 kHz signal the Microcontroller 51 can generate other signals at other frequencies, such as 120 kHz and 115 kHz. To effectively drive the series-resonant circuit with the generated signal, the Microcontroller 51 will adjust the resonant frequency of the tuned circuit by switching in additional capacitors (shown in FIG. 4 as C 1 and C 2 ) in parallel with the fixed capacitor C. One method for accomplishing this multi-frequency control is to use time-slicing, a practice known in electrical engineering. For example in FIGS. 4 and 5 , the microcontroller could generate a signal at 125 kHz driving the series tuned circuit with switches S 1 and S 2 open, then the frequency could be changed to 120 kHz and S 1 could then be closed adding capacitor C 1 in parallel with C, lowering the tuned circuit resonant frequency to 120 kHz. The system will be able to use this technique to power Tags tuned to different frequencies and control tuned tags or groups of tuned tags to create lighting effects such as blinking, dimming, or a flickering fire. The Microcontroller 51 will use time-slicing to sequentially power the Tags 17 of various frequencies. For example, the Mat 15 could generate 125 kHz for 10 ms, then 120 kHz for 10 ms, and 115 kHz for 10 ms, then repeat, powering Tags tuned to 125 kHz, 120 kHz and 115 kHz, respectively. As long as the switching speed is fast enough, the human eye cannot see the flickering. This technique can be easily extended to allow the system to turn off, blink, or dim Tags 17 of a particular frequency. FIG. 6 shows an example of how time division frequency switching can be used for illumination. The figure depicts a one-second window of signal generated by an Advanced Mat 15 divided into 100 ms slices. In the example, the 125 kHz signal turns on a white Tag 17 , 120 kHz turns on a blue Tag 17 and 115 kHz turns on a red Tag 17 . The user would see the white tag appear to be steadily illuminated with the blue tag blinking at the beginning of the second and the red tag blinking at the end of the second. Another method of controlling and powering Tags 17 of different frequencies is to use the superposition principle where signals with the desired frequencies are summed together and used to drive the series resonant circuit. The sum of the relevant signals, e.g., 125 kHz, 120 kHz, and 115 kHz, can be done in analog hardware as shown in the diagram of FIG. 7 , or it can be done in a spreadsheet tool such as Excel, and stored in a lookup table on the Microcontroller 51 for output to the series-resonant circuit. The signals can be either sine waves or square waves. To power a Tag 17 tuned to one of the described frequencies the series-resonant circuit would need to be tuned to the desired frequency of operation using the switches, e.g. no switches for 125 kHz, S 1 on=120 KHz, S 2 on=115 kHz. The benefit of this approach is that a signal containing all of the relevant frequencies is used to drive the series-tuned circuit and the proper frequency is selected by simply switching in or out capacitors to tune the series resonant circuit to one of the frequencies, powering a tag or group of tags tuned to the selected frequency. The time-slicing approach discussed above could then be used to create lighting effects by sequentially powering tags tuned to different frequencies. Auxiliary Mat—Shown in FIG. 9 , the Auxiliary Mat 19 consists of a tuned circuit consisting of a Auxiliary Winding 61 and Auxiliary Capacitor 63 . The significant difference between an Auxiliary Mat 19 and a Power Mat 13 is that the Auxiliary Mat 19 has no driver circuit; it is completely passive. The Auxiliary Mat 19 is placed next to the Powered Mat 13 to extend the size of the powered area, and has no independent power source, but inductively couples with the primary mat causing itself to resonate producing another field capable of powering tags. Additionally, when an Auxiliary Mat 19 is placed near a Power Mat 13 the brightness of the Power Mat 13 will be reduced because of the power leeched by the Auxiliary Mat 19 to extend the field. Optional physical connectors can attach the Auxiliary Mat 19 to the Power Mat 13 to ensure it is positioned optimally. These features are unique to this application and invention. There is no need for these features in typical induction mats used for charging batteries. Implementing these features would make a power charging mat very inefficient and could possibly damage devices attempting to charge with the system. For example a typical charging mat would not need a light sensor or timer or the ability to use multiple frequencies to blink or flicker lights. Charging mats for cell phones would never include this feature. Thus, the prior art teaches away from the construction of this invention and embodiment. In building this embodiment, a method of creating the Primary Winding 21 using multi-conductor ribbon cable has been developed, making it easier to install the system on furniture and other systems. FIG. 8 shows the construction of a ribbon-cable based Primary Winding 21 . The Interconnect Board 71 has two Insulation Displacement Connectors (IDC) 73 a 73 b . Once the Ribbon Cable 75 is connected to the IDCs 73 a 73 b , the assembly forms a coil usable as a Primary Winding 21 between the Board Output Terminals 79 in the Lighting System 11 . While the interconnect board 71 is shown as a separate entity its functionality could be directly integrated with another circuit board and does not need to be independent. For example a single board could incorporate all of the mat electronics including the connectors and wiring to use a multi conductor ribbon cable for the primary winding 21 . The example in FIG. 8 shows a five-conductor Ribbon Cable 75 but this could be easily extended to 14 or more conductors. To select the number of turns on the coil a Jumper 77 is used to connect the desired number of turns to the output terminals 79 . This system effectively creates a jumper-tunable Primary Winding (inductor) 21 that permits rapid integration with existing furniture such as tables and counter. If this coil system were not used, a custom coil would need to be wound using individual strands of wire, making construction more difficult and time consuming. Other Applications for the Lighting System—As stated earlier, wireless illumination system described here could be used for model lighting, illuminated games, and furniture. FIG. 1 shows the Mat 13 in use with a Tag 17 , Christmas Village Model Home 79 , and Drinking Glass 81 . Further discussion and examples follow. a. A restaurant/bar can have a Primary Winding embedded in tables and bar areas and activate different frequencies to create different colors, or blinking in glasses, shot glasses, plates, coasters, check holders, menus, etc. as a signal to its patrons of specials, last call, or other similar restaurant-wide announcements without using a loud-speaker. b. A user can embed a Primary Winding 21 , Power Mat 13 , or Advanced Mat 15 under an aquarium, and employ frequency switching with a three-color LED that has three different coils tuned to each primary color of the LED to create any desired color. c. A Christmas village can include the Lighting System 11 , allowing a someone to build, modify and play with the model buildings in a way that is not possible today, due to safety concerns and the possibility of twisted power cords. d. Poker chips that would illuminate when placed in the center of a poker table. e. A chess set where the chess board generates a field to illuminate chess pieces. f. Powered vase with the primary winding located in the base or mouth allowing inductively powered flowers to be illuminated. The flowers would have coils located in the stems and the LED in the flower itself. An advanced mat/winding could be used to control the color or blinking of the flowers. g. A powered tablecloth that could be placed on an existing table to power dishes, glasses, or other objects. h. Shoes that could illuminate and/or change color when the wearer walks on a stage or other item with a power mat embedded inside. i. A car playset using this lighting system could allow cars to light up and or light up with different colors or flash when placed in specific areas of the playset. While this invention has been described as it is currently built, the invention is not limited to the disclosed embodiments, but can be employed in various equivalent arrangements included within the spirit and scope of the claims. Other embodiments could include the following structure and improvements: a. The ribbon cable coil that creates the primary coil could wrap around the mat multiple times for more turns. For example, two turns with ten-conductor ribbon cable is equivalent to 20 actual turns. b. Other types of multi-conductor cables could be used in the primary winding mat wiring in addition to ribbon cable, such as Cat 5 Ethernet and DB9 serial cables; c. The Tags could incorporate capacitors or other energy storage devices to allow them to operate for a time after power is removed from the mat, so a tag-equipped glass could continue emitting light while a user drinks from the glass and it is separated from the Primary Winding. d. System could support auto-tuning of the mat capacitors to maximize performance of the mat's time varying magnetic field. e. Ability to connect Power Mats and Auxiliary Mats with physical connectors that ensure proper placement, enlarging the area in which a Tag may be powered. f. The Power Mat can be integrated into a table, affixing the primary winding set under the table top. g. The Power Mat can be integrated into toys and play sets to allow other pieces of the play set to illuminate when placed in certain locations or on the set in general. h. As discussed in the prior examples, tags can be embedded into various objects such as glasses, toys, game pices, clothing/shoes, dishes, and numerous items.
The invention is an induction-based lighting system designed to provide power to model displays and other similar applications. The first part of the system is the wireless Power Mat that is placed under the model houses and used as the base for the village, and contains a primary winding that interacts with secondary windings placed inside display components to provide lighting effects, such as one finds in model Christmas villages. The electrical characteristics of the primary winding can be controlled by a microcontroller to make lights in the models blink or change as a user desires.
Analyze the document's illustrations and descriptions to summarize the main idea's core structure and function.
[ "CROSS-REFERENCES TO RELATED APPLICATIONS None.", "STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT None.", "THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT None.", "INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC None.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The invention concerns wireless inductive lighting systems for models, decorative lighting, and communications using variable frequency power.", "Background Art During special occasions, many families enjoy setting model displays on mantels or around Christmas trees, such as 18th century villages and manger scenes.", "The village is made up of multiple building models all with their own light source.", "Each building is positioned and their light source is connected to a power strip to give the buildings their power.", "All the power cables are then hidden carefully under a white fabric resembling snow.", "There are many problems with this system.", "Once the models are positioned and their power cables are connected, it is very time intensive to reposition the models.", "This requires unplugging the power cable, moving the model, plugging in the power cable and hiding the cable.", "Also, the large number of power cables all connecting to a single outlet presents a fire hazard as well as risks tripping a circuit breaker.", "Additionally, efforts to hide all of the power cables are time consuming and is seldom aesthetically pleasing.", "Lastly, when these models are removed at the end of the season, the large number of power cords make storing the Christmas village very cumbersome.", "One approach to lessen the difficulty is to use battery-powered lighting.", "However, these devices often experience battery acid leakage and corrosion while in long-term storage between device usage.", "These displays would benefit greatly by a method of lighting the models that did not involve a power cord for every lighted model or batteries.", "The invention herein described uses inductive power provided by a first winding in a mat, delivered to second windings that are part of the model(s) to be lit.", "Use of inductive power is well known in electrical engineering;", "Nikola Tesla first demonstrated such power transfer in the late 19th century.", "Many systems exist to charge batteries and other devices.", "However, recent products are seeking to use contactless power transfer, often to charge a mobile phone or other battery-powered device by sitting it on a recharging mat.", "A primary coil in the mat creates a time varying magnetic field that interacts with and delivers power to a secondary coil in the device to be charged.", "A popular development group for near field inductive power is the Wireless Power Consortium (“WPC”), formed in 2008 to assist companies developing products.", "The WPC specification, developed less than two years later, defines its own operating parameters to transfer upwards of 5 W using ac frequencies of 100 to 205 kHz, and includes communications between the mat and device being charged.", "The WPC specification is fairly complex, detailing control signals to actuate a primary coil that interacts with a secondary coil in a device to be powered and a digital logic control communication protocol.", "The Consortium's specification also includes a definition of a primary coil that is specific in width (40 mm) and thickness (2mm), among other details of construction, including wire gage, shielding, etc.", "It is aimed at charging an expensive cell phone, and not appropriate for inexpensive lighting systems that are inherently capable of operation under a wide range of electrical conditions.", "What is needed is a lighting system designed to provide power by induction to inexpensive lighting devices.", "BRIEF SUMMARY OF THE INVENTION The invention shown in FIG. 1 is an induction-based Lighting System 11 designed to provide power to model displays and other similar applications.", "The first part of the system is the wireless Power Mat 13 that is placed under the model houses and used as the base for the village.", "The Power Mat 13 replaces the decorative cloth or felt base typically used as the base for the village.", "The Mat 13 is powered from a standard AC wall adapter or batteries and generates a time-varying magnetic field to inductively power lights through a secondary winding.", "Mats can be different sizes to suit the avid Christmas decorator along with individuals looking to set up their model quickly.", "The Lighting System uses a small wireless illumination “Tag”", "17 that can fit inside the models with a light-emitted diode (“LED”) and other basic circuitry, including a secondary winding that interacts with the mat.", "This Tag 17 replaces incandescent lights currently in the models, as well as with the power cable that is made unnecessary.", "Tags 17 are populated with lights of different brightness, color and blinking or flickering features.", "The following explanation discusses one embodiment of the invention, comprising a flexible Christmas village mat that can be rolled for easy storage, and several inductively powered lights.", "Other applications using the same invention are also discussed.", "BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) FIG. 1 shows the Lighting System in use.", "FIG. 2A shows one embodiment of a Tag's physical construction.", "FIG. 2B shows one possible schematic of a Tag.", "FIG. 3 shows the Power Mat construction.", "FIG. 4 is a block diagram of one embodiment of an Advanced Mat.", "FIG. 5 shows a time division block diagram.", "FIG. 6 provides an example of time division frequency switching.", "FIG. 7 shows a method of varying frequencies using superposition.", "FIG. 8 shows a Primary Winding build from five-conductor ribbon cable.", "FIG. 9 shows a block diagram of one embodiment of an Auxiliary Mat.", "DETAILED DESCRIPTION OF THE INVENTION The invention described herein builds upon the basic inductive wireless power transfer system (specifically resonant inductive coupling) with enhancements to specifically support a wireless illumination system for models (model rail road sets, Christmas villages), games (illuminated chess sets, children's play sets with light up cars), furniture (illuminated cups in movie theatres and trendy bars, doll cases, flower vase with light up flowers, kids teapot table or table runner with light up dishes, and aquariums where waterproof Tags are located at the bottom of the aquarium), and flooring (where illuminated shoes and other items that could light up when placed in certain locations).", "As shown in FIG. 1 , the invention 11 comprises two essential components: a wireless Power Mat 13 and illumination Tags 17 .", "A Primary Winding 21 is embedded within the Mat 13 , typically not visible to users, but is represented as the inductive Primary Winding 21 in FIG. 3 .", "Power is transferred inductively between the Power Mat 13 and multiple Tags 17 simultaneously and Tags 17 can be designed with circuitry to blink or flicker.", "The Power Mat 13 supports the ability to operate on multiple frequencies using time slicing allowing it to independently control Tags 17 tuned to different frequencies.", "A more complex Advanced Auxiliary Mat 15 that acts in accordance with sensors and switch inputs is also described, incorporating a Light Sensor 31 to automatically activate in darkness, as well as a Timer 33 and Pushbutton 35 to allow the user to turn it on for a preset period or programmed schedule, or change the frequency with the Pushbutton 35 .", "Finally, a user can employ an Auxiliary Mat 19 , depicted in the electronic representation shown in FIG. 9 , which is identical to the Power Mat 13 , except that it obtains its power by reacting with the Power Mat's Primary Winding 21 .", "The Auxiliary Mat 19 is simply properly placed next to the Power Mat 13 .", "The Power Mat's Primary Winding 21 delivers power to the winding in the Auxiliary Mat 19 , which in turn, provides power to the Tags 17 placed on the Auxiliary Mat 19 .", "Illuminator Tags—As shown in FIGS. 2A and 2B , the Tags 17 consist of a parallel tuned LC-resonant circuit composed of the Secondary Winding 27 and Tag Capacitor 28 , typically tuned in the neighborhood of 125 kHz, and an LED 25 .", "The impedance of a parallel tuned resonant circuit approaches infinity at the resonant frequency, which means that the voltage induced in the Tag's Coil 27 (which is at or near the resonant frequency of the circuit) is not absorbed by the tuned circuit but is instead used by the LED 25 to provide light.", "The amount of energy absorbed by the Tag 17 from the Power Mat 13 is dependent on many factors including strength of the field, proximity of the Tag 17 to the Mat 13 , orientation of the Tag 17 , number of turns and size of the Tag's Coil (or Secondary Winding) 27 .", "Basically, the more magnetic field lines that are cut by the Tag's Secondary Winding 27 , the more energy that is extracted from the field and available to power the LED 25 and whatever other circuitry is on the Tag 17 .", "The most simple design uses an LED to rectify the alternating current generated in the Secondary Coil 27 of the Tag to power said LED 25 .", "A more complex tag design would rectify the alternating current generated by the Power Mat 13 to create lighting effects on the Tag 17 such as a flickering fire.", "To simplify the Tag 17 construction, the Tag's Secondary Winding 27 is etched onto a circuit Board 24 (shown in FIG. 2A ) using standard circuit board manufacturing techniques which ensures consistent performance.", "The LED 25 and Capacitor 28 are also soldered to the Board 24 which provides a convenient structure for the Tag 17 .", "Additionally, a small commercially available ferrite core inductor can be used instead of an air core coil or circuit-board etched coil allowing a more compact design in some situations.", "As long as the Tag 17 can be placed inside of the Power Mat's magnetic field, it will illuminate, providing a large number of possibilities in terms of applications since the magnetic field will penetrate most non-conductive materials, including plastic, wood, and glass, allowing the Tag 17 and or the Power Mat 13 to be embedded inside objects and table tops.", "A single Power Mat 13 can be used to power multiple Tags 17 simultaneously due to the size of the Power Mat's magnetic field.", "A multi-frequency mat can be used to control Tags or sets of Tags 17 tuned to different frequencies by changing the frequency or strength of the generated magnetic field for different lengths of times to independently power sets of tuned tags to create lighting effects.", "For example the 125 KHz Tags could be on steadily, while the 120 KHz Tags blink, and the 115 kHz Tags flicker, emulating the motion of fire.", "Wireless Power Mat Details—The system uses resonant inductive coupling to transfer power from the Power Mat 13 to the Tag 17 .", "As shown in FIG. 3 , the Power Mat is powered by a direct-current power source, and consists of an Oscillator 41 , Driver 43 , Mat Capacitor 45 , and a Primary Winding 21 which is embedded in the Power Mat 13 .", "The Mat Capacitor 45 and Primary Winding 21 make up a series-tuned resonant inductor-capacitor Circuit 22 designed to resonate at 125 kHz in this application.", "Optional Mat Connectors 23 are indicated on FIG. 1 that can be used to affix an Auxiliary Mat and hold it in place to receive power from a Power Mat 13 most efficiently;", "it is assumed that a practitioner in the art can design many types of connectors that would perform this function with ease.", "Driving the series-resonant Circuit 22 at its resonant frequency minimizes its impedance resulting in maximum current flow through the circuit which results in a maximum magnetic field strength generated by the Primary Winding 21 , providing maximum power transfer between the Power Mat 13 and Tag 17 .", "The size of the field is determined by the winding dimensions, the current running through the windings, and the number of turns.", "In this embodiment, the Primary Winding 21 consists of a 14-turn coil of 26 awg enameled copper wire that runs around the perimeter of the Power Mat 13 .", "Larger systems may require multiple windings, also known as coils.", "To create a field large enough to be useful in this application, the Primary Winding 21 runs along the perimeter of the Power Mat 13 .", "To date, the largest mat constructed has been 10″ by 44″, but the invention is not restricted to any particular size.", "Tags 17 are placed inside the perimeter of the Primary Winding 21 or just outside it to ensure they are energized.", "To make the mat easily stored, the Primary Winding 21 is placed between two neoprene sheets allowing it to be rolled up for storage.", "Current embodiments have employed hand wound windings but costs can easily be reduced in production by using a printed or foil-based coil.", "A mundane 12 Vdc desktop power supply provides power to the current embodiment of the Power Mat 13 , but it could be made battery-powered to support use in toys and other portable applications.", "Advanced Power Mat—While the term “mat”", "is used throughout this specification, the mat could be an actual mat, or a table top or other furniture with a coil and related electronics integrated into the top surface.", "FIG. 4 shows a block diagram of this Advanced Power Mat (“Advanced Mat”) 15 with the enhancements ideal for wireless illumination.", "The system consists of a Microcontroller 51 which controls current through the Primary Winding 21 .", "It interfaces with a Light Sensor 31 to control the Advanced Mat 15 in low light conditions.", "It incorporates a Timer 33 and Pushbutton Interface 35 to activate the Timer to allow the user to activate the invention for a programmed period of time.", "This feature is also useful for games.", "The Timer can also be used to control the mat at different times of the day.", "Finally, the Microcontroller 51 has an interface to connect with switches and buttons in support of integrating the invention into toys (e.g. pushing a button could make certain lights blink, dim, or turn on) The Microcontroller 51 generates the 125 kHz waveforms to drive the Primary Winding 21 by operation of a Mat Driver 53 .", "After the Microcontroller 51 operates the Mat Driver 53 to energize the Mat's Primary Winding 21 , Tags 17 placed on the Mat's surface will illuminate.", "In addition to generating a steady 125 kHz signal the Microcontroller 51 can generate other signals at other frequencies, such as 120 kHz and 115 kHz.", "To effectively drive the series-resonant circuit with the generated signal, the Microcontroller 51 will adjust the resonant frequency of the tuned circuit by switching in additional capacitors (shown in FIG. 4 as C 1 and C 2 ) in parallel with the fixed capacitor C. One method for accomplishing this multi-frequency control is to use time-slicing, a practice known in electrical engineering.", "For example in FIGS. 4 and 5 , the microcontroller could generate a signal at 125 kHz driving the series tuned circuit with switches S 1 and S 2 open, then the frequency could be changed to 120 kHz and S 1 could then be closed adding capacitor C 1 in parallel with C, lowering the tuned circuit resonant frequency to 120 kHz.", "The system will be able to use this technique to power Tags tuned to different frequencies and control tuned tags or groups of tuned tags to create lighting effects such as blinking, dimming, or a flickering fire.", "The Microcontroller 51 will use time-slicing to sequentially power the Tags 17 of various frequencies.", "For example, the Mat 15 could generate 125 kHz for 10 ms, then 120 kHz for 10 ms, and 115 kHz for 10 ms, then repeat, powering Tags tuned to 125 kHz, 120 kHz and 115 kHz, respectively.", "As long as the switching speed is fast enough, the human eye cannot see the flickering.", "This technique can be easily extended to allow the system to turn off, blink, or dim Tags 17 of a particular frequency.", "FIG. 6 shows an example of how time division frequency switching can be used for illumination.", "The figure depicts a one-second window of signal generated by an Advanced Mat 15 divided into 100 ms slices.", "In the example, the 125 kHz signal turns on a white Tag 17 , 120 kHz turns on a blue Tag 17 and 115 kHz turns on a red Tag 17 .", "The user would see the white tag appear to be steadily illuminated with the blue tag blinking at the beginning of the second and the red tag blinking at the end of the second.", "Another method of controlling and powering Tags 17 of different frequencies is to use the superposition principle where signals with the desired frequencies are summed together and used to drive the series resonant circuit.", "The sum of the relevant signals, e.g., 125 kHz, 120 kHz, and 115 kHz, can be done in analog hardware as shown in the diagram of FIG. 7 , or it can be done in a spreadsheet tool such as Excel, and stored in a lookup table on the Microcontroller 51 for output to the series-resonant circuit.", "The signals can be either sine waves or square waves.", "To power a Tag 17 tuned to one of the described frequencies the series-resonant circuit would need to be tuned to the desired frequency of operation using the switches, e.g. no switches for 125 kHz, S 1 on=120 KHz, S 2 on=115 kHz.", "The benefit of this approach is that a signal containing all of the relevant frequencies is used to drive the series-tuned circuit and the proper frequency is selected by simply switching in or out capacitors to tune the series resonant circuit to one of the frequencies, powering a tag or group of tags tuned to the selected frequency.", "The time-slicing approach discussed above could then be used to create lighting effects by sequentially powering tags tuned to different frequencies.", "Auxiliary Mat—Shown in FIG. 9 , the Auxiliary Mat 19 consists of a tuned circuit consisting of a Auxiliary Winding 61 and Auxiliary Capacitor 63 .", "The significant difference between an Auxiliary Mat 19 and a Power Mat 13 is that the Auxiliary Mat 19 has no driver circuit;", "it is completely passive.", "The Auxiliary Mat 19 is placed next to the Powered Mat 13 to extend the size of the powered area, and has no independent power source, but inductively couples with the primary mat causing itself to resonate producing another field capable of powering tags.", "Additionally, when an Auxiliary Mat 19 is placed near a Power Mat 13 the brightness of the Power Mat 13 will be reduced because of the power leeched by the Auxiliary Mat 19 to extend the field.", "Optional physical connectors can attach the Auxiliary Mat 19 to the Power Mat 13 to ensure it is positioned optimally.", "These features are unique to this application and invention.", "There is no need for these features in typical induction mats used for charging batteries.", "Implementing these features would make a power charging mat very inefficient and could possibly damage devices attempting to charge with the system.", "For example a typical charging mat would not need a light sensor or timer or the ability to use multiple frequencies to blink or flicker lights.", "Charging mats for cell phones would never include this feature.", "Thus, the prior art teaches away from the construction of this invention and embodiment.", "In building this embodiment, a method of creating the Primary Winding 21 using multi-conductor ribbon cable has been developed, making it easier to install the system on furniture and other systems.", "FIG. 8 shows the construction of a ribbon-cable based Primary Winding 21 .", "The Interconnect Board 71 has two Insulation Displacement Connectors (IDC) 73 a 73 b .", "Once the Ribbon Cable 75 is connected to the IDCs 73 a 73 b , the assembly forms a coil usable as a Primary Winding 21 between the Board Output Terminals 79 in the Lighting System 11 .", "While the interconnect board 71 is shown as a separate entity its functionality could be directly integrated with another circuit board and does not need to be independent.", "For example a single board could incorporate all of the mat electronics including the connectors and wiring to use a multi conductor ribbon cable for the primary winding 21 .", "The example in FIG. 8 shows a five-conductor Ribbon Cable 75 but this could be easily extended to 14 or more conductors.", "To select the number of turns on the coil a Jumper 77 is used to connect the desired number of turns to the output terminals 79 .", "This system effectively creates a jumper-tunable Primary Winding (inductor) 21 that permits rapid integration with existing furniture such as tables and counter.", "If this coil system were not used, a custom coil would need to be wound using individual strands of wire, making construction more difficult and time consuming.", "Other Applications for the Lighting System—As stated earlier, wireless illumination system described here could be used for model lighting, illuminated games, and furniture.", "FIG. 1 shows the Mat 13 in use with a Tag 17 , Christmas Village Model Home 79 , and Drinking Glass 81 .", "Further discussion and examples follow.", "a. A restaurant/bar can have a Primary Winding embedded in tables and bar areas and activate different frequencies to create different colors, or blinking in glasses, shot glasses, plates, coasters, check holders, menus, etc.", "as a signal to its patrons of specials, last call, or other similar restaurant-wide announcements without using a loud-speaker.", "b. A user can embed a Primary Winding 21 , Power Mat 13 , or Advanced Mat 15 under an aquarium, and employ frequency switching with a three-color LED that has three different coils tuned to each primary color of the LED to create any desired color.", "c. A Christmas village can include the Lighting System 11 , allowing a someone to build, modify and play with the model buildings in a way that is not possible today, due to safety concerns and the possibility of twisted power cords.", "d. Poker chips that would illuminate when placed in the center of a poker table.", "e. A chess set where the chess board generates a field to illuminate chess pieces.", "f. Powered vase with the primary winding located in the base or mouth allowing inductively powered flowers to be illuminated.", "The flowers would have coils located in the stems and the LED in the flower itself.", "An advanced mat/winding could be used to control the color or blinking of the flowers.", "g. A powered tablecloth that could be placed on an existing table to power dishes, glasses, or other objects.", "h. Shoes that could illuminate and/or change color when the wearer walks on a stage or other item with a power mat embedded inside.", "i. A car playset using this lighting system could allow cars to light up and or light up with different colors or flash when placed in specific areas of the playset.", "While this invention has been described as it is currently built, the invention is not limited to the disclosed embodiments, but can be employed in various equivalent arrangements included within the spirit and scope of the claims.", "Other embodiments could include the following structure and improvements: a. The ribbon cable coil that creates the primary coil could wrap around the mat multiple times for more turns.", "For example, two turns with ten-conductor ribbon cable is equivalent to 20 actual turns.", "b. Other types of multi-conductor cables could be used in the primary winding mat wiring in addition to ribbon cable, such as Cat 5 Ethernet and DB9 serial cables;", "c. The Tags could incorporate capacitors or other energy storage devices to allow them to operate for a time after power is removed from the mat, so a tag-equipped glass could continue emitting light while a user drinks from the glass and it is separated from the Primary Winding.", "d. System could support auto-tuning of the mat capacitors to maximize performance of the mat's time varying magnetic field.", "e. Ability to connect Power Mats and Auxiliary Mats with physical connectors that ensure proper placement, enlarging the area in which a Tag may be powered.", "f. The Power Mat can be integrated into a table, affixing the primary winding set under the table top.", "g. The Power Mat can be integrated into toys and play sets to allow other pieces of the play set to illuminate when placed in certain locations or on the set in general.", "h. As discussed in the prior examples, tags can be embedded into various objects such as glasses, toys, game pices, clothing/shoes, dishes, and numerous items." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application takes priority under 35 U.S.C. 119(e) to U.S. Provisional application No. 60/147,310 filed Aug. 5, 1999, which is incorporated by reference herein to the extent that it is not inconsistent with the disclosures herein. BACKGROUND OF THE INVENTION This invention relates generally to devices and methods for the measurement of wavelengths of light or the detection of light at selected wavelengths. U.S. Pat. Nos. 5,838,437 and 5,892,582 described optical wavelength scanners and spectrum analyzers which employ tunable Fiber Fabry-Perot filters (FFP-TF) for wavelength scanning. The devices and systems described in these patents incorporate a multiwavelength reference for in-situ calibration of the FFP-TF for wavelength measurement. The use of the multiwavelength reference minimizes the effects of drift and nonlinearity in the FFP-TF scanner. In a specific embodiment, the multiwavelength reference is a combination of a fixed fiber Fabry-Perot filter which provides a comb of wavelengths of known separation and a reference fiber Bragg grating (FBG) which provides a reference peak or notch to identify the wavelength of a peak in the comb. The comb of references provides reference peaks over the wavelength range of interest for detection or analysis. U.S. Pat. Nos. 5,838,437 and 5,892,582 are incorporated by reference herein in their entirety. This invention provides improved devices for highly accurate wavelength detection which employ a pre-calibrated FFP-TF obviating the need for in situ calibration of the filter, significantly simplifying the devices which generally have fewer components and simplified hardware and software, decreasing the cost of the devices, and increasing the speed of measurement without significant loss in wavelength accuracy. The improved devices can be used in a variety of optical applications including tunable receivers, sensor interrogators, wavelength meters, optical tracking filters and optical channel analyzers. The devices of this invention generally avoid the use of optical switches needed in prior devices employing in situ calibration to allow comparison of reference and measured wavelengths. A one time calibration of the FFP-TF is performed at a range of temperatures over the intended operating temperature range of the filter to generate a set of calibration coefficients for curve fitting. These coefficients, which embody correction data for wavelength and power error, are used to correct wavelength and power measurements in devices using the FFP-TF scanner. FFP-TF can also be precalibrated for bandwidth variation. The calibration can be performed once (at multiple temperatures) after the device is constructed rather than periodically within the instrument in the field. FFP-TF employ piezoelectric actuators or transducers (PZTs) to change the length of the FP cavity and thereby tune the wavelength of the filter. PZTs exhibit dynamic nonlinearities arising from nonlinear length dependence upon voltage, voltage hysterisis, and temperature. PZTs retain a memory, in the form of remnant polarization, of the voltage and temperature conditions to which they have been exposed. In particular, after exposure of a PZT to very low temperatures, it can take up to a month for the PZT to return to its original steady state polarization condition. Because of this sensitivity to voltage and temperature conditions, in situ calibration, as described in the U.S. patents noted above, was believed to be necessary to obtain wavelength accuracy in the 10-20 picometer range desirable for applications noted herein. The inventors have discovered that application of a low level negative voltage to the PZTs used in the FFP-TFs, rapidly resets the PZT to its original steady state condition eliminating remnant polarization due to the voltage or temperature history of the PZT. The set of calibration coefficients determined for a FFP-TF with the PZTs in this steady state condition can then be employed at any time in the future, if the PZT of the FFP-TF is reset to the steady state condition prior to making wavelength measurement and applying the pre-determined calibration coefficients. The length of PZTs are typically changed by application of a positive variable voltage to the PZT. In a low voltage PZT, the range of voltage applied to change the length ranges from 0 to about 40 volts. An FFP-TF is typically tuned through a wavelength range by application of a voltage ramp to the PZT of the filter. Calibration of the FFP-TF associates a voltage applied to the PZT to the wavelength passed by the filter at that applied voltage. The inventors have found that application of a low negative voltage, e.g., −5 volts to the PZT of the FFP-TF (a stacked PZT) resets the PZT to the original steady state condition eliminating remnant polarization within about 1 minute. After the PZT is reset, application of the predetermined calibration coefficients provides reproducible, accurate wavelength calibration of the filter. The negative reset voltage employed is preferably less in magnitude than about 25% of the depoling voltage (typically about 40 volts) of the PZT, i.e., less than about 10 V in magnitude. The resetting procedure has demonstrated excellent stability over a wide range of temperatures. The devices of this invention can be programed to apply the resetting voltage to the PZTs of the FFP-TF whenever the device is turned on. Devices can also be equipped with a controller and voltage source that allows application of the negative reset voltage periodically when the device is in operation, selectively as determined by the operator of the device, or in response to an event or condition, such as the detection of a loss in wavelength accuracy or a change in operating conditions. SUMMARY OF THE INVENTION The invention provides a calibration method for tunable optical filters which is particularly useful with Fiber Fabry-Perot Tunable Filters (FFP-TFs) and specifically useful with FFP-TFs which employ piezoelectric transducers as tuning elements. The method is generally applicable to achieve wavelength error of less than about ±50 picometers over the operating temperatures of the filter. Preferably, application of the calibration method achieves wavelength error of less than about ±20 picometers over the operating temperature range of the filter. The invention also provides tunable optical filters calibrated by the inventive method and optical devices for measurement of wavelengths of light which comprise the inventive calibrated tunable optical filters. The calibration method involves the determination of calibration coefficients employing a plurality of known wavelengths of light over a wavelength region of interest to generate a set of calibration coefficients. A set of calibration coefficients is determined at each of a plurality of temperatures over the operating temperature range of the filter. The operating temperature range of the filter may, for example, range from 0° C. to about 60° C. In a preferred embodiment sets of calibration coefficients are determined at intervals of about 1° C. to about 10° C. over the operating temperature range of the device. For example, a set of calibration coefficients over the desired wavelength range spanned by the plurality of known wavelengths is determined for each interval of 1° C., 5° C. 10° C. over the operating temperature range of the filter. The sets of calibration coefficients determined for the tunable filter which span the wavelength region of interest and the operating temperature range of interest are stored in a microprocessor or computer. The stored coefficients are then employed to correct measurements or determinations of unknown wavelengths by the tunable filter. The stored coefficients can also be used to set the tunable filter to detect the presence of a selected wavelength among a plurality of wavelengths such as in a broad band of wavelengths. To correct a wavelength measured by the tunable filter at a selected temperature, a set of coefficients determined at the selected temperature or within about 1° C. to about 10° C. of the selected temperature is employed. Where no set of coefficients is determined at the selected temperature, it is preferred to correct the wavelength measurement by interpolation employing two sets of coefficients measured at temperatures which bracket the selected temperature. In a specific embodiment, the calibration method of this invention is applied to tunable filters which employ piezoelectric transducers as tuning elements. In these filters, the length of the piezoelectric transducer is changed to tune the wavelength of the filter. In a preferred application of the calibration method to such filters, a low negative voltage is applied to the piezoelectric transducer prior to determination of calibration coefficients and prior to the measurement of wavelength using the filter. The invention also provides optical devices-for the measurement or detection of wavelengths of light or for the selection of a wavelength of light from a plurality of wavelengths of light. These devices comprise a tunable filter, preferably a fiber Fabry-Perot tunable filter, calibrated by the method of this invention. The device comprises the tunable filter and some means for storing the sets of calibration coefficients and employing the sets of calibration coefficients to correct wavelength measurements by the filter. The sets of calibration coefficients may also be used to tune the filter, e.g., by adjusting the voltage applied to a piezoelectric transducer, to receive or pass a selected wavelength. Other aspects and benefits of the invention will become apparent on review of the following figures and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph of wavelength error (nm) at several temperatures as a function of wavelength (nm) when the FFP-TF calibration is performed at a single temperature (60° C.) using one known reference wavelength. Temperatures of error measurement are indicated on the graph. FIG. 2 is a graph of wavelength error (nm) at several temperatures as a function of wavelength (nm) when the FFP-TF calibration is performed at one temperature (60° C.) at two known reference wavelengths which bracket the wavelength range of interest. Temperatures of error measurement are indicated on the graph. FIG. 3 is a graph illustrating wavelength error (picometers) at 25° C. using the FFP-TF calibration method of this invention. Two sets of calibration coefficients measured at 20° C. and 30° C., respectively, are applied to interpolate wavelength measurements made at 25° C. FIG. 4A is a schematic drawing of a calibrated optical channel analyzer containing a pre-calibrated FFP-TF. A set of calibration coefficients is stored in the computer or microprocessor of the device. FIG. 4B is a schematic drawing of another optical channel analyzer of this invention containing a pre-calibrated FFP-TF. FIG. 4C is a schematic drawing of a calibrated sensor interrogator containing a pre-calibrated FFP-TF. FIG. 5 is a schematic drawing of a calibrated channel monitor containing a pre-calibrated FFP-TF. FIG. 6 is a schematic drawing of a calibrated tunable receiver containing a pre-calibrated FFP-TF. DETAILED DESCRIPTION OF THE INVENTION The invention is further illustrated by reference to the drawings in which the same numbers are used to refer to the same device elements. FIGS. 1-3 are graphs illustrating the effectiveness of different calibration schemes for an FFP-TF in wavelength measurement. FIG. 1 illustrates wavelength error for measurements at varying temperatures (as indicated in the figure at 0-60° C.) when the filter is calibrated at a single temperature using one known reference wavelength (at the lower end of the operating wavelength range). The calibration was performed at 60° C. in the upper range of operating temperatures. Large errors of the order of several nanometers are observed when using this calibration procedure. This calibration method is not useful for obtaining accuracies in the 10-20 picometer range. Wavelength error is the difference between the wavelength measured by the FFP-TF as adjusted by the calibration method employed of a known reference wavelength and the actual wavelength of that known reference wavelength. FIG. 2 illustrates the application of a similar calibration method employing two known reference wavelengths (one at the lower and one at the upper limit of the operating wavelength range to bracket the range) and a calibration performed at one temperature (60° C.). While the errors with measurements performed at different temperatures (as indicated in the graph) are significantly lower than with the calibration of FIG. 1 (of the order of hundreds of picometers) using this calibration is procedure, the errors are still too high for the intended applications. FIG. 3 illustrates the application of interpolation using a set of calibration curves measured at temperatures over the operating range of the filter. The graph shows the errors in measurements made at 25° C. by applying interpolation of calibration coefficients measured at 20° C. and 30° C. The errors are less than about 10 picometers which is within the desired accuracy level for intended applications of wavelength scanners and spectrum analyzers. In a specific example, an FFP-TF with PZT reset to the steady state condition is calibrated using known reference wavelengths, such as the comb of wavelengths supplied by the multiwavelength reference of U.S. Pat. Nos. 5,838,437 and 5,892,582, at a plurality of temperatures over the operating range of the filter. A variety of curve-fitting procedures can be employed to generate calibration coefficients. For example, calibration coefficients can be generated by curve-fitting of required corrections to a 6-order polynomial. Calibration curves can be measured every 1-10° C. over the operating temperature of the filter. A set of calibration curves generated every 5° C. was found to provide wavelength measurements within the desired accuracy of 10-20 picometers. Calibration coefficients are stored in the microprocessor or computer of the scanner or spectrum analyzer, e.g., in a look-up table, for correction of wavelength measurements. Since calibration is temperature dependent, the temperature of the FFP-TF at the time of wavelength measurement must be known. A temperature sensor can be used to detect the temperature and convey the measurement to the device microprocessor or computer for use in calibration. Alternatively, the FFP-TF can be maintained at a constant known temperature. FIGS. 4A-C, 5 and 6 illustrate various device configurations which employ the pre-calibrated FFP-TF described herein. FIG. 4A is a schematic diagram of a calibrated optical channel analyzer where optical coupling of device elements is illustrated in heavy lines and electrical coupling with thin lines. The device contains a pre-calibrated FFP-TF and a set of calibration coefficients generated at temperatures over the operating temperature range of the device are stored in the device computer or microprocessor. Two or more known reference wavelengths bracketing or spanning the wavelength range of the device are provided. In the illustrated device, the reference wavelengths are provided using reference FBGs ( 1 ) optionally coupled to a reference light source ( 4 ). The reference light source is optically coupled (heavy lines) through coupler 9 to the reference FBGs which reflect light back at their Bragg wavelength. The reflected FBG wavelengths pass through coupler 9 and into the calibrated FFP-TF. Subject light, (i.e., light that is being measured) from any source ( 5 ) enters the device through coupler ( 7 ) (only a small portion of the subject light need be diverted into the analyzer) and passes through coupler ( 9 ) to the FFP-TF ( 10 ). The wavelengths passed by the filter are scanned by application of a voltage ramp to the PZT (not specifically illustrated) of the FFP-TF ( 10 ). Light passing through the filter is detected by detector ( 15 ) and associated with the voltage applied to the PZT. The voltage ramp is applied through an FFP controller (FFPC) ( 20 ). A temperature sensor ( 25 ) measures the temperature of the FFP-TF and supplies this information to the computer or microprocessor ( 30 ) for use in wavelength calibration. Prior to making a measurement and preferably when the device is turned on, a negative reset voltage, preferably −5V, is applied to the PZT of the filter ( 10 ) to reset the PZT to the steady state condition. The negative reset voltage is applied through the FFPC or may be applied through a separate voltage supply. Further details of scanning the FFP-TF and data collection are provided in the U.S. patents noted above. Details of the structure of FFP-TFs are also provided in the patents noted above. The Bragg wavelength of an FBG changes with temperature. Reference FBGs are preferably temperature controlled or temperature compensated to minimize wavelength change with temperature. Further, if the temperature dependency of wavelength of the FBG is known, it is possible to correct for temperature variation. FBG temperature correction curves are then provided to the computer or microprocessor ( 30 ). In this case, the FBG temperature is monitored with a temperature sensor and temperature information supplied to the computer or microprocessor ( 30 ) to facilitate calibration. Subject light with two bracketing reference wavelengths (λ 1 and λ 2 ) enters the FFP-TF which is scanned over the wavelength range and light exiting the FFP-TF is detected as a function of applied voltage. The stored calibration coefficients of the FFP-TF appropriate for the temperature of the measurement and the measurements of the known reference wavelengths are applied to the collected data to generate calibrated wavelength measurements. This device can be used to identify the wavelengths of light in the subject light or to detect the presence of light of a selected wavelength in the subject light. FIG. 4B illustrates an alternative optical channel analyzer in which the reference FBGs ( 1 ) are optically coupled in series with the pre-calibrated FFP-TP ( 10 ). Again the computer or microprocessor ( 30 ) of the device is provided with calibration coefficients generated for the FFP-TF ( 10 ). A portion of the subject light ( 5 ) is coupled into the device through coupler ( 7 ). Subject light in this case is sufficiently broad band to encompass the FBG wavelength. Two notches in the subject light are created by passage of the light through the reference FBGs ( 1 ). Subject light with two reference notches enters the FFP-TF ( 10 ). Subject light may be a combination of light to be integrated and a broad background source extending to the reference wavelengths. The FFP-TF ( 10 ) is scanned and light is detected (at detector 15 ) as a function of voltage applied to the PZT of the filter. The calibration procedure is applied to the data collected to determine wavelength. As in the device of FIG. 4A, a reset voltage is provided to the PZT prior to collecting data to ensure the accuracy of application of the calibration coefficients. FIG. 4C illustrates a sensor interrogator. In this device, a sensor array ( 40 ), e.g., an FBG sensor array and two or more reference FBGs ( 1 ) are optically coupled to a light source ( 35 ) through coupler ( 7 ). Light reflected back from the reference FBGs and the sensor FBGs is coupled through coupler ( 7 ) into the FFP-TF filter ( 10 ). Resetting of the PZT, data collection and calibration is performed as in the devices of FIGS. 4A and B. FIG. 5 illustrates a calibrated channel monitor having a pre-calibrated FFP-TF ( 10 ) of this invention. In this case WDM input ( 50 ) is coupled into the FFP-TF ( 10 ) through coupler ( 47 ). Reference wavelength peaks are generated by reflection from the FBGs which are optically coupled to a reference light source ( 35 ). The reflected reference wavelengths also enter the FFP-TF ( 10 ). Resetting of the PZT, data collection and calibration are performed as in the devices of FIGS. 4A-4B. The device configurations of FIGS. 4A-C and 5 contain optional optical isolators ( 26 ). The FFP-TF employed in the configurations of FIGS. 4A-C and 5 are narrow BW filters. Preferred BW for these filters are in the range 30-40 picometers. FIG. 6 illustrates a calibrated tunable receiver. WDM input ( 50 ) passes through reference FBGs ( 1 ) generating reference wavelength notches outside of the WDM signal band, and into the FFP-TF ( 10 ). The computer generates, from a desired wavelength, the temperature, and stored calibrations coefficients, a voltage value which is applied via the FFPC ( 20 ) to the pre-calibrated FFP-TF ( 10 ). This voltage tunes the FFP-TF to approximately the desired wavelength. A small high frequency (2 KHz) AC signal is superimposed on the DC driving voltage. Approximately 90% of the signal passing through the FFP-TF is sent to the highbandwidth detector ( 15 ) as a data signal via coupler ( 7 ). The remaining 10% of the signal is diverted through a low frequency photodiode ( 60 ). The voltage output of the photodiode circuit is the input for a phase detector which produces an error signal indicating the magnitude and direction of the deviation of the FFP-TF output wavelength from the desired wavelength. This error signal is superimposed on the voltage supplied by the FFPC ( 20 ) to lock the FFP-TF output to the desired wavelength. The advantage of the wavelength-PZT voltage calibration is that the FFP-TF can be tuned within locking range of the desired wavelength by knowing only the desired wavelength and the temperature of the FFP-TF. This permits one wavelength in a signal carrying multiple wavelengths to be detected. The closed loop wavelength locking circuit extends from the FFP-TF ( 10 ) through coupler C 1 ( 7 ), the phase detector ( 60 ), the FFPC ( 20 ) and back to the FFP-TF ( 10 ). The tuning circuit extends from the computer ( 30 ) through the FFPC ( 20 ) to the FFP-TF ( 10 ). The FFP-TF used in the tunable receiver of FIG. 6 has a relatively broad bandwidth (BW) sufficient to pass the modulation on the WDM channel. Typical BW for filters for this application are 300-400 picometers. The calibration method of this invention generates calibration coefficients employing a plurality of known wavelengths. These known wavelengths can be provided, for example, as described in U.S. Pat. Nos. 5,838,437 or 5,892,582, using a multi-wavelength reference, by providing a plurality of FBGs which reflect a plurality of known wavelengths or by providing one or more reference light sources which generate a plurality of known wavelengths. When employing certain sources of known reference wavelengths, it may be necessary to employ a bandwidth filter to isolate a selected spectral region for use as a reference. The calibrated FFP-TF and optical devices containing them can be employed in a variety of optical applications including those noted in U.S. Pat. Nos. 5,838,437 and 5,892,582. These patents also provide descriptions of the operation and structure of FBGs and provide references describing various FFP-TF. These patents further provide detail of the operation of FFP-TF as scanners and the determination of wavelengths using such filters. The PZT resetting procedure described herein can be employed with PZTs in any application, particularly those applications where accurate, reproducible changes in length as a function of temperature and voltage are required. This invention provides a method for calibrating all PZTs. All references cited herein are incorporated in their entirety by reference herein to the extent not inconsistent herewith.
A method for calibrating tunable optical filters, calibrated tunable filters and devices employing such filters. The method is of particular use with fiber Fabry-Perot tunable filters and more particularly for filters which employ piezoelectric transducers as tuning elements. Sets of calibration coefficients are generated which span the wavelength region and operating temperature range of the filter. Calibrated tunable filters are combined with a means for storing the sets of calibration coefficients and means for correcting wavelength measurements using the sets of coefficients in devices which measure wavelengths of light. The sets of calibration coefficients can also be used to tune the filter to pass a selected wavelength of interest.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application takes priority under 35 U.S.C. 119(e) to U.S. Provisional application No. 60/147,310 filed Aug. 5, 1999, which is incorporated by reference herein to the extent that it is not inconsistent with the disclosures herein.", "BACKGROUND OF THE INVENTION This invention relates generally to devices and methods for the measurement of wavelengths of light or the detection of light at selected wavelengths.", "U.S. Pat. Nos. 5,838,437 and 5,892,582 described optical wavelength scanners and spectrum analyzers which employ tunable Fiber Fabry-Perot filters (FFP-TF) for wavelength scanning.", "The devices and systems described in these patents incorporate a multiwavelength reference for in-situ calibration of the FFP-TF for wavelength measurement.", "The use of the multiwavelength reference minimizes the effects of drift and nonlinearity in the FFP-TF scanner.", "In a specific embodiment, the multiwavelength reference is a combination of a fixed fiber Fabry-Perot filter which provides a comb of wavelengths of known separation and a reference fiber Bragg grating (FBG) which provides a reference peak or notch to identify the wavelength of a peak in the comb.", "The comb of references provides reference peaks over the wavelength range of interest for detection or analysis.", "U.S. Pat. Nos. 5,838,437 and 5,892,582 are incorporated by reference herein in their entirety.", "This invention provides improved devices for highly accurate wavelength detection which employ a pre-calibrated FFP-TF obviating the need for in situ calibration of the filter, significantly simplifying the devices which generally have fewer components and simplified hardware and software, decreasing the cost of the devices, and increasing the speed of measurement without significant loss in wavelength accuracy.", "The improved devices can be used in a variety of optical applications including tunable receivers, sensor interrogators, wavelength meters, optical tracking filters and optical channel analyzers.", "The devices of this invention generally avoid the use of optical switches needed in prior devices employing in situ calibration to allow comparison of reference and measured wavelengths.", "A one time calibration of the FFP-TF is performed at a range of temperatures over the intended operating temperature range of the filter to generate a set of calibration coefficients for curve fitting.", "These coefficients, which embody correction data for wavelength and power error, are used to correct wavelength and power measurements in devices using the FFP-TF scanner.", "FFP-TF can also be precalibrated for bandwidth variation.", "The calibration can be performed once (at multiple temperatures) after the device is constructed rather than periodically within the instrument in the field.", "FFP-TF employ piezoelectric actuators or transducers (PZTs) to change the length of the FP cavity and thereby tune the wavelength of the filter.", "PZTs exhibit dynamic nonlinearities arising from nonlinear length dependence upon voltage, voltage hysterisis, and temperature.", "PZTs retain a memory, in the form of remnant polarization, of the voltage and temperature conditions to which they have been exposed.", "In particular, after exposure of a PZT to very low temperatures, it can take up to a month for the PZT to return to its original steady state polarization condition.", "Because of this sensitivity to voltage and temperature conditions, in situ calibration, as described in the U.S. patents noted above, was believed to be necessary to obtain wavelength accuracy in the 10-20 picometer range desirable for applications noted herein.", "The inventors have discovered that application of a low level negative voltage to the PZTs used in the FFP-TFs, rapidly resets the PZT to its original steady state condition eliminating remnant polarization due to the voltage or temperature history of the PZT.", "The set of calibration coefficients determined for a FFP-TF with the PZTs in this steady state condition can then be employed at any time in the future, if the PZT of the FFP-TF is reset to the steady state condition prior to making wavelength measurement and applying the pre-determined calibration coefficients.", "The length of PZTs are typically changed by application of a positive variable voltage to the PZT.", "In a low voltage PZT, the range of voltage applied to change the length ranges from 0 to about 40 volts.", "An FFP-TF is typically tuned through a wavelength range by application of a voltage ramp to the PZT of the filter.", "Calibration of the FFP-TF associates a voltage applied to the PZT to the wavelength passed by the filter at that applied voltage.", "The inventors have found that application of a low negative voltage, e.g., −5 volts to the PZT of the FFP-TF (a stacked PZT) resets the PZT to the original steady state condition eliminating remnant polarization within about 1 minute.", "After the PZT is reset, application of the predetermined calibration coefficients provides reproducible, accurate wavelength calibration of the filter.", "The negative reset voltage employed is preferably less in magnitude than about 25% of the depoling voltage (typically about 40 volts) of the PZT, i.e., less than about 10 V in magnitude.", "The resetting procedure has demonstrated excellent stability over a wide range of temperatures.", "The devices of this invention can be programed to apply the resetting voltage to the PZTs of the FFP-TF whenever the device is turned on.", "Devices can also be equipped with a controller and voltage source that allows application of the negative reset voltage periodically when the device is in operation, selectively as determined by the operator of the device, or in response to an event or condition, such as the detection of a loss in wavelength accuracy or a change in operating conditions.", "SUMMARY OF THE INVENTION The invention provides a calibration method for tunable optical filters which is particularly useful with Fiber Fabry-Perot Tunable Filters (FFP-TFs) and specifically useful with FFP-TFs which employ piezoelectric transducers as tuning elements.", "The method is generally applicable to achieve wavelength error of less than about ±50 picometers over the operating temperatures of the filter.", "Preferably, application of the calibration method achieves wavelength error of less than about ±20 picometers over the operating temperature range of the filter.", "The invention also provides tunable optical filters calibrated by the inventive method and optical devices for measurement of wavelengths of light which comprise the inventive calibrated tunable optical filters.", "The calibration method involves the determination of calibration coefficients employing a plurality of known wavelengths of light over a wavelength region of interest to generate a set of calibration coefficients.", "A set of calibration coefficients is determined at each of a plurality of temperatures over the operating temperature range of the filter.", "The operating temperature range of the filter may, for example, range from 0° C. to about 60° C. In a preferred embodiment sets of calibration coefficients are determined at intervals of about 1° C. to about 10° C. over the operating temperature range of the device.", "For example, a set of calibration coefficients over the desired wavelength range spanned by the plurality of known wavelengths is determined for each interval of 1° C., 5° C. 10° C. over the operating temperature range of the filter.", "The sets of calibration coefficients determined for the tunable filter which span the wavelength region of interest and the operating temperature range of interest are stored in a microprocessor or computer.", "The stored coefficients are then employed to correct measurements or determinations of unknown wavelengths by the tunable filter.", "The stored coefficients can also be used to set the tunable filter to detect the presence of a selected wavelength among a plurality of wavelengths such as in a broad band of wavelengths.", "To correct a wavelength measured by the tunable filter at a selected temperature, a set of coefficients determined at the selected temperature or within about 1° C. to about 10° C. of the selected temperature is employed.", "Where no set of coefficients is determined at the selected temperature, it is preferred to correct the wavelength measurement by interpolation employing two sets of coefficients measured at temperatures which bracket the selected temperature.", "In a specific embodiment, the calibration method of this invention is applied to tunable filters which employ piezoelectric transducers as tuning elements.", "In these filters, the length of the piezoelectric transducer is changed to tune the wavelength of the filter.", "In a preferred application of the calibration method to such filters, a low negative voltage is applied to the piezoelectric transducer prior to determination of calibration coefficients and prior to the measurement of wavelength using the filter.", "The invention also provides optical devices-for the measurement or detection of wavelengths of light or for the selection of a wavelength of light from a plurality of wavelengths of light.", "These devices comprise a tunable filter, preferably a fiber Fabry-Perot tunable filter, calibrated by the method of this invention.", "The device comprises the tunable filter and some means for storing the sets of calibration coefficients and employing the sets of calibration coefficients to correct wavelength measurements by the filter.", "The sets of calibration coefficients may also be used to tune the filter, e.g., by adjusting the voltage applied to a piezoelectric transducer, to receive or pass a selected wavelength.", "Other aspects and benefits of the invention will become apparent on review of the following figures and detailed description.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph of wavelength error (nm) at several temperatures as a function of wavelength (nm) when the FFP-TF calibration is performed at a single temperature (60° C.) using one known reference wavelength.", "Temperatures of error measurement are indicated on the graph.", "FIG. 2 is a graph of wavelength error (nm) at several temperatures as a function of wavelength (nm) when the FFP-TF calibration is performed at one temperature (60° C.) at two known reference wavelengths which bracket the wavelength range of interest.", "Temperatures of error measurement are indicated on the graph.", "FIG. 3 is a graph illustrating wavelength error (picometers) at 25° C. using the FFP-TF calibration method of this invention.", "Two sets of calibration coefficients measured at 20° C. and 30° C., respectively, are applied to interpolate wavelength measurements made at 25° C. FIG. 4A is a schematic drawing of a calibrated optical channel analyzer containing a pre-calibrated FFP-TF.", "A set of calibration coefficients is stored in the computer or microprocessor of the device.", "FIG. 4B is a schematic drawing of another optical channel analyzer of this invention containing a pre-calibrated FFP-TF.", "FIG. 4C is a schematic drawing of a calibrated sensor interrogator containing a pre-calibrated FFP-TF.", "FIG. 5 is a schematic drawing of a calibrated channel monitor containing a pre-calibrated FFP-TF.", "FIG. 6 is a schematic drawing of a calibrated tunable receiver containing a pre-calibrated FFP-TF.", "DETAILED DESCRIPTION OF THE INVENTION The invention is further illustrated by reference to the drawings in which the same numbers are used to refer to the same device elements.", "FIGS. 1-3 are graphs illustrating the effectiveness of different calibration schemes for an FFP-TF in wavelength measurement.", "FIG. 1 illustrates wavelength error for measurements at varying temperatures (as indicated in the figure at 0-60° C.) when the filter is calibrated at a single temperature using one known reference wavelength (at the lower end of the operating wavelength range).", "The calibration was performed at 60° C. in the upper range of operating temperatures.", "Large errors of the order of several nanometers are observed when using this calibration procedure.", "This calibration method is not useful for obtaining accuracies in the 10-20 picometer range.", "Wavelength error is the difference between the wavelength measured by the FFP-TF as adjusted by the calibration method employed of a known reference wavelength and the actual wavelength of that known reference wavelength.", "FIG. 2 illustrates the application of a similar calibration method employing two known reference wavelengths (one at the lower and one at the upper limit of the operating wavelength range to bracket the range) and a calibration performed at one temperature (60° C.).", "While the errors with measurements performed at different temperatures (as indicated in the graph) are significantly lower than with the calibration of FIG. 1 (of the order of hundreds of picometers) using this calibration is procedure, the errors are still too high for the intended applications.", "FIG. 3 illustrates the application of interpolation using a set of calibration curves measured at temperatures over the operating range of the filter.", "The graph shows the errors in measurements made at 25° C. by applying interpolation of calibration coefficients measured at 20° C. and 30° C. The errors are less than about 10 picometers which is within the desired accuracy level for intended applications of wavelength scanners and spectrum analyzers.", "In a specific example, an FFP-TF with PZT reset to the steady state condition is calibrated using known reference wavelengths, such as the comb of wavelengths supplied by the multiwavelength reference of U.S. Pat. Nos. 5,838,437 and 5,892,582, at a plurality of temperatures over the operating range of the filter.", "A variety of curve-fitting procedures can be employed to generate calibration coefficients.", "For example, calibration coefficients can be generated by curve-fitting of required corrections to a 6-order polynomial.", "Calibration curves can be measured every 1-10° C. over the operating temperature of the filter.", "A set of calibration curves generated every 5° C. was found to provide wavelength measurements within the desired accuracy of 10-20 picometers.", "Calibration coefficients are stored in the microprocessor or computer of the scanner or spectrum analyzer, e.g., in a look-up table, for correction of wavelength measurements.", "Since calibration is temperature dependent, the temperature of the FFP-TF at the time of wavelength measurement must be known.", "A temperature sensor can be used to detect the temperature and convey the measurement to the device microprocessor or computer for use in calibration.", "Alternatively, the FFP-TF can be maintained at a constant known temperature.", "FIGS. 4A-C, 5 and 6 illustrate various device configurations which employ the pre-calibrated FFP-TF described herein.", "FIG. 4A is a schematic diagram of a calibrated optical channel analyzer where optical coupling of device elements is illustrated in heavy lines and electrical coupling with thin lines.", "The device contains a pre-calibrated FFP-TF and a set of calibration coefficients generated at temperatures over the operating temperature range of the device are stored in the device computer or microprocessor.", "Two or more known reference wavelengths bracketing or spanning the wavelength range of the device are provided.", "In the illustrated device, the reference wavelengths are provided using reference FBGs ( 1 ) optionally coupled to a reference light source ( 4 ).", "The reference light source is optically coupled (heavy lines) through coupler 9 to the reference FBGs which reflect light back at their Bragg wavelength.", "The reflected FBG wavelengths pass through coupler 9 and into the calibrated FFP-TF.", "Subject light, (i.e., light that is being measured) from any source ( 5 ) enters the device through coupler ( 7 ) (only a small portion of the subject light need be diverted into the analyzer) and passes through coupler ( 9 ) to the FFP-TF ( 10 ).", "The wavelengths passed by the filter are scanned by application of a voltage ramp to the PZT (not specifically illustrated) of the FFP-TF ( 10 ).", "Light passing through the filter is detected by detector ( 15 ) and associated with the voltage applied to the PZT.", "The voltage ramp is applied through an FFP controller (FFPC) ( 20 ).", "A temperature sensor ( 25 ) measures the temperature of the FFP-TF and supplies this information to the computer or microprocessor ( 30 ) for use in wavelength calibration.", "Prior to making a measurement and preferably when the device is turned on, a negative reset voltage, preferably −5V, is applied to the PZT of the filter ( 10 ) to reset the PZT to the steady state condition.", "The negative reset voltage is applied through the FFPC or may be applied through a separate voltage supply.", "Further details of scanning the FFP-TF and data collection are provided in the U.S. patents noted above.", "Details of the structure of FFP-TFs are also provided in the patents noted above.", "The Bragg wavelength of an FBG changes with temperature.", "Reference FBGs are preferably temperature controlled or temperature compensated to minimize wavelength change with temperature.", "Further, if the temperature dependency of wavelength of the FBG is known, it is possible to correct for temperature variation.", "FBG temperature correction curves are then provided to the computer or microprocessor ( 30 ).", "In this case, the FBG temperature is monitored with a temperature sensor and temperature information supplied to the computer or microprocessor ( 30 ) to facilitate calibration.", "Subject light with two bracketing reference wavelengths (λ 1 and λ 2 ) enters the FFP-TF which is scanned over the wavelength range and light exiting the FFP-TF is detected as a function of applied voltage.", "The stored calibration coefficients of the FFP-TF appropriate for the temperature of the measurement and the measurements of the known reference wavelengths are applied to the collected data to generate calibrated wavelength measurements.", "This device can be used to identify the wavelengths of light in the subject light or to detect the presence of light of a selected wavelength in the subject light.", "FIG. 4B illustrates an alternative optical channel analyzer in which the reference FBGs ( 1 ) are optically coupled in series with the pre-calibrated FFP-TP ( 10 ).", "Again the computer or microprocessor ( 30 ) of the device is provided with calibration coefficients generated for the FFP-TF ( 10 ).", "A portion of the subject light ( 5 ) is coupled into the device through coupler ( 7 ).", "Subject light in this case is sufficiently broad band to encompass the FBG wavelength.", "Two notches in the subject light are created by passage of the light through the reference FBGs ( 1 ).", "Subject light with two reference notches enters the FFP-TF ( 10 ).", "Subject light may be a combination of light to be integrated and a broad background source extending to the reference wavelengths.", "The FFP-TF ( 10 ) is scanned and light is detected (at detector 15 ) as a function of voltage applied to the PZT of the filter.", "The calibration procedure is applied to the data collected to determine wavelength.", "As in the device of FIG. 4A, a reset voltage is provided to the PZT prior to collecting data to ensure the accuracy of application of the calibration coefficients.", "FIG. 4C illustrates a sensor interrogator.", "In this device, a sensor array ( 40 ), e.g., an FBG sensor array and two or more reference FBGs ( 1 ) are optically coupled to a light source ( 35 ) through coupler ( 7 ).", "Light reflected back from the reference FBGs and the sensor FBGs is coupled through coupler ( 7 ) into the FFP-TF filter ( 10 ).", "Resetting of the PZT, data collection and calibration is performed as in the devices of FIGS. 4A and B. FIG. 5 illustrates a calibrated channel monitor having a pre-calibrated FFP-TF ( 10 ) of this invention.", "In this case WDM input ( 50 ) is coupled into the FFP-TF ( 10 ) through coupler ( 47 ).", "Reference wavelength peaks are generated by reflection from the FBGs which are optically coupled to a reference light source ( 35 ).", "The reflected reference wavelengths also enter the FFP-TF ( 10 ).", "Resetting of the PZT, data collection and calibration are performed as in the devices of FIGS. 4A-4B.", "The device configurations of FIGS. 4A-C and 5 contain optional optical isolators ( 26 ).", "The FFP-TF employed in the configurations of FIGS. 4A-C and 5 are narrow BW filters.", "Preferred BW for these filters are in the range 30-40 picometers.", "FIG. 6 illustrates a calibrated tunable receiver.", "WDM input ( 50 ) passes through reference FBGs ( 1 ) generating reference wavelength notches outside of the WDM signal band, and into the FFP-TF ( 10 ).", "The computer generates, from a desired wavelength, the temperature, and stored calibrations coefficients, a voltage value which is applied via the FFPC ( 20 ) to the pre-calibrated FFP-TF ( 10 ).", "This voltage tunes the FFP-TF to approximately the desired wavelength.", "A small high frequency (2 KHz) AC signal is superimposed on the DC driving voltage.", "Approximately 90% of the signal passing through the FFP-TF is sent to the highbandwidth detector ( 15 ) as a data signal via coupler ( 7 ).", "The remaining 10% of the signal is diverted through a low frequency photodiode ( 60 ).", "The voltage output of the photodiode circuit is the input for a phase detector which produces an error signal indicating the magnitude and direction of the deviation of the FFP-TF output wavelength from the desired wavelength.", "This error signal is superimposed on the voltage supplied by the FFPC ( 20 ) to lock the FFP-TF output to the desired wavelength.", "The advantage of the wavelength-PZT voltage calibration is that the FFP-TF can be tuned within locking range of the desired wavelength by knowing only the desired wavelength and the temperature of the FFP-TF.", "This permits one wavelength in a signal carrying multiple wavelengths to be detected.", "The closed loop wavelength locking circuit extends from the FFP-TF ( 10 ) through coupler C 1 ( 7 ), the phase detector ( 60 ), the FFPC ( 20 ) and back to the FFP-TF ( 10 ).", "The tuning circuit extends from the computer ( 30 ) through the FFPC ( 20 ) to the FFP-TF ( 10 ).", "The FFP-TF used in the tunable receiver of FIG. 6 has a relatively broad bandwidth (BW) sufficient to pass the modulation on the WDM channel.", "Typical BW for filters for this application are 300-400 picometers.", "The calibration method of this invention generates calibration coefficients employing a plurality of known wavelengths.", "These known wavelengths can be provided, for example, as described in U.S. Pat. Nos. 5,838,437 or 5,892,582, using a multi-wavelength reference, by providing a plurality of FBGs which reflect a plurality of known wavelengths or by providing one or more reference light sources which generate a plurality of known wavelengths.", "When employing certain sources of known reference wavelengths, it may be necessary to employ a bandwidth filter to isolate a selected spectral region for use as a reference.", "The calibrated FFP-TF and optical devices containing them can be employed in a variety of optical applications including those noted in U.S. Pat. Nos. 5,838,437 and 5,892,582.", "These patents also provide descriptions of the operation and structure of FBGs and provide references describing various FFP-TF.", "These patents further provide detail of the operation of FFP-TF as scanners and the determination of wavelengths using such filters.", "The PZT resetting procedure described herein can be employed with PZTs in any application, particularly those applications where accurate, reproducible changes in length as a function of temperature and voltage are required.", "This invention provides a method for calibrating all PZTs.", "All references cited herein are incorporated in their entirety by reference herein to the extent not inconsistent herewith." ]
FIELD OF THE INVENTION AND RELATED ART STATEMENT The present invention relates to a clathrate compound and, more particularly, to a novel clathrate compound including a water-soluble microbicide, which improves the handleability and the stability of the microbicide therein. In water systems such as cooling water systems in various factory plants or the pulp and paper industries, slime of various bacteria, fungi, animals and vegetables adheres to the ducts or lines to cause various problems. Hitherto, for the purpose of preventing the problems caused by slime or the like in such systems, a microbicide (slime-controlling agent) has generally been employed as it is easily handled, and it is relatively inexpensive. For instance, 5-chloro-2-methyl-4-isothiazolin-3-one of the following formula (I) (hereinafter referred to as "Cl-MIT") is widely used as a slime-controlling agent, a bactericide, an algicide or a fungicide for various water systems such as a cooling water system, a papermaking process system or a swimming pool, as it has an excellent microbicidal activity. ##STR2## However, Cl-MIT is extremely stimulative to the skin and caution is necessary when handling the same, though it has an excellent microbicidal activity. Since Cl-MIT decomposes extremely easily, water-soluble microbicides on the market contain a Large amount of Mg salts so as to stabilize Cl-MIT therein. Therefore, such commercial microbicides cannot be employed in the field of latex and emulsion which do not accept Mg salts. Cl-MIT can be separated from the water-soluble microbicides on the market by extraction methods using organic solvents, but the thus-extracted Cl-MIT is unstable especially under heat, so that it decomposes within one or two days even at a temperature of about 40° C. For these reasons, special storage conditions are necessary such as storing the compound in a refrigerator. In order to overcome problems such as above, the present applicant has already proposed clathrate compounds having a water-soluble microbicide such as Cl-MIT containing a host compound such as a bisphenol halide (Japanese Patent Laid-Open Publication No. 1-190602). Among the host compounds proposed in Japanese Patent Laid-Open Application No. 1-190602, 2,2'-methylenebis(4-chlorophenol) has been considered preferred. OBJECT AND SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved clathrate compound including a water-soluble microbicide such as Cl-MIT. The clathrate compound of the present invention is characterized by comprising a water-soluble microbicide and a phenolic compound of the following general formula (1) or (2): ##STR3## wherein R represents an alkylidene group having from 2 to 4 carbon atoms. ##STR4## wherein each of R 1 and R 2 represents an alkyl group having from 2 to 4 carbon atoms. As the water-soluble microbicide, preferred is Cl-MIT having the above-mentioned structural formula (I). Specifically, the clathrate compound of the present invention is composed of a water-soluble microbicide such as Cl-MIT, as the guest compound, and the above-mentioned phenolic compound, as the host compound, wherein the host compound includes the guest compound therein. DESCRIPTION OF THE PREFERRED EMBODIMENTS Bisphenolic compounds of formula (1) to be used in the present invention include, for example, 4,4'-ethylidenebisphenol, 2,4'-isopropylidenebisphenol, 2,2'-vinylidenebisphenol, 4,4'-isobutylidenebisphenol, 2,6'-sec-butylidenebisphenol, etc. Phenolic compounds of formula (2) also to be used in the present invention include, for example, 2,4-di-tert-butylphenol, 2,6-di-tert-butylphenol, 2,4-di-propylphenol, 2-propyl-4-tert-butylphenol, etc. The water-soluble microbicide for use in the present invention may be any one that may form a clathrate compound with the above-mentioned phenolic compound. Cl-MIT which is widely used as an effective microbicide is preferable, but this is not limitative. The clathrate compound of the present invention, comprising such a water-soluble microbicide and a phenolic compound, may easily be prepared by reacting them in an organic solvent or in water. When an organic solvent is used for preparing it, a solution, which is prepared by dissolving any of the above-mentioned phenolic compounds in an ordinary organic solvent such as methanol, ethanol or acetone is mixed with a water-soluble microbicide such as Cl-MIT or with a mixture containing a water-soluble microbicide such as Cl-MIT and some impurities, etc., and reacted with the water-soluble microbicide. Accordingly, the intended clathrate compound precipitates out as a solid product, which is filtered and separated by ordinary methods. When water is used for the same, the above-mentioned phenolic compound is directly added to an aqueous solution containing a water-soluble microbicide as the guest compound, and mixed by stirring. The aqueous solution to be used is not limited to one containing only a water-soluble microbicide as the guest compound. As in the above-mentioned case using an organic solvent, the solution may contain some impurities. The above-mentioned phenolic compound reacts with a water-soluble microbicide with high selectivity. Therefore, even when a water-soluble microbicide containing impurities such as side products is used directly as the raw meterial, a desired clathrate compound including selectively only the intended water-solube microbicide is obtained. The reaction temperature may range from 0° C. to 100° C. In general, it is approximately from 10° C. to 30° C. The reaction time is from about 0.5 to 24 hours. After the reaction, the clathrate compound is generally obtained as a solid product, which may be separated from the aqueous phase, washed with water and dried. Thus, the intended clathrate compound of the present invention is obtained. The molar ratio between the water-soluble microbicide such as Cl-MIT and the above-mentioned phenolic compound of formula (1) both constituting the clathrate compound of the present invention, is generally such that (water-soluble microbicide):(phenolic compound (1)) is from 1:0.2to 1:5. The molar ratio between the water-soluble microbicide such as Cl-MIT and the above-mentioned phenolic compound of formula (2), both constituting the clathrate compound of the present invention, is generally such that (water-soluble microbicide):(phenolic compound(2) )is from 1:0.2to 1:5. The clathrate compound of the present invention, thus obtained in the manner mentioned above, is generally powdery and may easily be shaped into tablets. Since the water-soluble microbicide is included as the host compound, the clathrate compound is low in toxicity and is easily handled, and the microbicide is prevented from reacting with other substance to lower its microbicidal activity during its use. When the clathrate compound of the present invention is put into water, the water-soluble microbicide in the clathrate compound is released slowly therefrom. For example, when a clathrate compound of the present invention including 3% by weight of Cl-MIT therein is put into water, the amount of Cl-MIT to be released from the clathrate compound into water is as low as several 100 mg/liter. Therefore, a water-dispersible product containing a clathrate compound of the invention having the above-mentioned Cl-MIT concentration (3% by weight) is extremely preferred, as its stimulation to the skin is lessened. The compound of the present invention may be applied to a slow-release microbicide which slowly releases its active ingredient therefrom. Moreover, Since the clathrate compound of the present invention includes a water-soluble microbicide such as Cl-MIT as its guest compound, the microbicide therein is stabilized against heat. The clathrate compound of the present invention may be used, for example, according to the methods mentioned below. (1) The compound is packed in a column, and a liquid to be treated is passed therethrough. (2) The compound is put into a bag or a cartridge which is permeable to water but does not dissolve in water, and the bag or cartridge is dipped in or floated above water systems. (3) The compound of powder or tablet is dispersed in water systems. (4) The compound is mixed with coating compositions, resins, etc., and the mixture is coated onto the surfaces of a device to be used in water systems, etc. (5) The compound is adhered to the surfaces of the objects to be protected, by any suitable means. It is preferred that the clathrate compound of the present invention is added to water to be treated in an amount of from 0.00001 to 0.5% by weight in terms of the concentration of the water-soluble microbicide such as Cl-MIT included in the clathrate compound. The stability of the clathrate compound of the present invention is often poor in water, when it is added with no other additive. When a nitroalcoholic compound is added to the clathrate compound of the present invention, then the stability of the compound in water may be elevated. The nitroalcoholic compound to be used for this purpose includes, for example, 2-chloro-2-nitro-ethanol, 1-chloro-1-nitro-2-propanol, 3-chloro-3-nitro-2-butanol, 2-chloro-2-nitro-1,3-butanediol, 1-chloro-1-nitro-2-butanol, 2-chloro-2-nitro-butanol, 2-chloro-2-nitro-3-pentanol, 2,2-dichrolo-2-nitro-ethanol, 2-bromo-2-chloro-2-nitro-ethanol, 3-chrolo-3-nitro-2,4-pentanediol, 4-chrolo-4-nitro-3-hexanol, 2-bromo-2-nitro-ethanol, 2-bromo-2-nitro-3-propanol, 2-bromo-2-nitro-1,3-butanediol, 3-bromo-3-nitro-2,4-pentanediol, 2,2-dibromo-2-nitro-ethanol, 1,1-dibromo-1-nitro-2-propanol, 4-bromo-4-nitro-3-hexanol, 2-fluoro-2-nitro-ethanol, 2-fluoro-2-nitro-1,3-butanediol, 3-Iodo-3-nitro-2-butanol, 2-chloro-2-fluoro-2-nitro-ethanol, 2-bromo-2-Iodo-2-nitro-ethanol, 2-chloro-2-nitro-1,3-propanediol, 2-bromo-2-nitro-1,3-propanediol. The amount of the compound to be added to the clathrate compound of the present invention is preferably from 0.1 to 5% by weight relative to the clathrate compound. If it is less than 0.1% by weight, a sufficient stabilizing effect cannot be attained. However even if it is more than 5% by weight, no difference in the stability-improving effect will be observed and therefore, such excess addition is not economical. When a microbicidal composition comprising the clathrate compound of the present invention and such a nitroalcoholic compound is added to water to be treated therewith, it is preferred that the amount of the composition to be added is approximately from 0.00001 to 0.5% by weight in terms of the concentration of the water-soluble microbicide in the composition. The clathrate compound of the present invention is helpful in powdering, stabilizing and concentrating the water-soluble microbicide included therein. In addition, since the clathrate compound of the present invention is a reaction product having high selectivity in particular compounds, it may also be used for separating and purifying particular water-soluble microbicides. For instance, Cl-MIT may be separated from a mixture comprising Cl-MIT and its side-product of 2-methyl-4-isothiazolin-3-one (hereinafter referred to as "MI"), though such separation has heretofore been difficult. This is accomplished by making only Cl-MIT selectively included in a host compound to give a clathrate compound, and then by separating the thus-included Cl-MIT from the clathrate compound. In this way, a high-purity Cl-MIT may be isolated from the mixture. To separate a water-soluble microbicide such as Cl-MIT from the clathrate compound including it, the following methods may be employed. (1) The clathrate compound is dipped in water. (2) The clathrate compound is dissolved in an organic solvent and then water is added thereto, whereby only the host compound is made precipitated. According to these methods, the water-soluble microbicide included in the clathrate compound dissolves out into water, and it is recovered as its aqueous solution. When a water-soluble microbicide is formed into a clathrate compound with the above-mentioned phenolic compound acting as the host compound, according to the present invention, it becomes solid so that its handleability is much improved. In addition, the dissolution of the microbicide component into water from the clathrate compound is significantly lowered, and the toxicity and the skin-stimulating property of the microbicide are reduced. Moreover, the microbicide in the clathrate compound is prevented from reacting with any other substance to lower its microbicidal activity during its use. Further, the heat-resistant stability of the microbicide is improved, as it is included in the clathrate compound. For these reasons, the clathrate compound of the present invention may be used effectively as a slow-release microbicide whereby the microbicidal activity may be maintained for a long period of time. In addition, since the clathrate compound of the present invention is helpful in powdering, stabilizing and concentrating the water-soluble microbicide therein and since the host compound selectively includes the water-soluble microbicide therein, the present invention is also useful for separating and purifying water-soluble microbicides. In particular, when Cl-MIT is used as the water-soluble microbicide, the present invention provides an excellent microbicidal product. Preferably, the clathrate compound of the present invention is most stable when used in the form of a microbicidal composition containing the compound along with a predetermined amount of a nitroalcoholic compound. The present invention will be described in more detail by means of the following examples, which are not intended to restrict the scope of the present invention. EXAMPLE 1 Production of Clathrate Compound of Cl-MIT and 2,4-Di-Ter-Butylphenol (by Methanol Solvent Method) 500 g of a water-soluble microbicide consisting essentially of Cl-MIT (Cl-MIT concentration: 10.4% by weight) were extracted with 200 g of chloroform, and the solvent in the chloroform layer was removed by distillation to separate Cl-MIT. The yield was 50 g, and the product contained 2 to 3% by weight of MI. 0.69 g (3.34 mmol) of 2,4-di-tert-butylphenol were put int a sample bottle and dissolved in 10 ml of methanol therein. 0.5 g (3.34 mmol) of the previously separated Cl-MIT were added thereto and mixed. After mixing, the mixture was left as it was, thereby removing the solvent thererfrom by natural drying to make crystals precipitated. The thus-obtained crystals were separated, washed with 2 ml of water and then dried. The product was analyzed by IR spectrography and NMR spectrography, and the Cl-MIT content in the product was measured by HPLC. As a result, the product was identified to be a clathrate compound of 2,4-di-tert-butylphenol/Cl-MIT of nearly 2/1 (by mol), having a Cl-MIT content of 25.83% by weight. EXAMPLE 2 Production of Clathrate Compound of Cl-MIT and 4,4'-Ethylidene-Bisphenol (By Methanol Solvent Method) The same process as in Example 1 was repeated, except that 0.5 g (3.34 mmol) of Cl-MIT and the same molar amount of 4,4'-ethylidene-bisphenol were used, and the product was analyzed in the same manner as in Example 1. The product was identified to be a clathrate compound of 4,4'-ethylidene-bisphenol/Cl-MIT of nearly 1/1 (by mol), having a Cl-MIT content of 37.84% by weight. EXAMPLE 3 Production of Clathrate Compound of Cl-MIT and 2,4-Di-Tert-Butylphenol (By Water Solvent Method) 1.436 g (6.95 mmol) of 2,4-di-tert-butylphenol and 10 g of an aqueous microbicidal solution consisting essentially of Cl-MIT (Cl-MIT concentration: 10.4% by weight, Cl-MIT content: 1.04 g (6.95 mmol)) were mixed and reacted, and left overnight. The crystals thus formed were separated from the aqueous layer, washed with 2 ml of water and then dried. The product was analyzed by IR spectrography and NMR spectrography, and the Cl-MIT content in the product was measured by HPLC. As a result, the product was identified to be a clathrate compound of 2,4-di-tert-butylphenol/Cl-MIT of nearly 2/1, having a Cl-MIT content of 25.8% by weight. TEST EXPERIMENT 1 Test for Thermal Stability (at 40° C.) of Cl-MIT In Its Clathrate Compound 10 g of each of the clathrate compounds obtained by the methanol solvent method in Examples 1 and 2 were put into a screw-cap bottle, which was then sealed. These bottles were set in a thermostat at 40° C. At intervals, the content in each bottle was sampled and analyzed by HPLC to determine the Cl-MIT content in the clathrate compound. From the data measured and the initial Cl-MIT content in the fresh compound, the retention percentage of Cl-MIT remained in the sampled clathrate compound was obtained. The results are shown in Table 1 below. For comparison, only Cl-MIT was tested in the same manner as above to obtain the retention percentage thereof. The results are also shown in Table 1. TABLE 1______________________________________ Retention Percentage of Cl-MIT (%) Molar Ratio initial after afterNo. Host Compound (guest/host) value 1 week 1 month______________________________________1 2,4-Di-tert- 1/2 100.0 97.6 97.2butylphenol2 4,4'-Ethylidene- 1/1 100.0 96.2 96.5bisphenol3 (Cl-MIT in the -- 100.0 0.0 0.0nude)______________________________________ From the test results, it has been confirmed that Cl-MIT in the nude blackened and decomposed in one week while the clathrate compound including Cl-MIT did not. TEST EXPERIMENT 2 Measurement of Cl-MIT Released into Water (at 25° C.) From Clathrate Compound Including It Each of the clathrate compounds obtained in Examples 1 and 2 was mixed with water to prepare an aqueous mixture having a Cl-MIT concentration of 3% by weight. The thus-prepared mixtures were kept in a thermostat tank at 25° C. and sampled at intervals. Each sample was passed through a 0.45 μm-millipore filter to thereby separate the clathrate compound from the aqueous phase. Then, the Cl-MIT concentration in the thus-separated aqueous phase was measured by HPLC, from which the amount of Cl-MIT released into water was determined. The amount of the clathrate compound tested, the amount of water added to the compound, and the amount of Cl-MIT released into water are shown in Table 2. For comparison, only Cl-MIT was tested in the same manner as above to obtain its amount dissolved in water. The results are also shown in Table 2. TABLE 2__________________________________________________________________________ Cl-MIT Cl-MIT Amount of Cl-MIT Amount (g) Concentration Concentration Released into Water (mg/liter)(*2) Host Clathrate in Sample in Water after after after afterNo. Compound Compound Water (wt. %) (mg/liter)(*1) 1 day 1 week 3 weeks 1__________________________________________________________________________ month4 2,4-Di-tert- 5.784 44.223 3 33940 721 700 681 664 butylphenol (21.%) (21%) (2.0%) (2.0%) (Cl-MIT content: 25.83 wt. %)5 4,4'- 3.137 36.829 3 32564 335 327 351 330 Ethylidene- (1.0%) (1.0%) (1.1%) (1.0%) bisphenol (Cl- MIT content: 37.84 wt. %)6 Cl-MIT 30000 (100%)__________________________________________________________________________ (*1) This means the ClMIT concentration in water, resulting from complete release of all ClMIT from the clathrate compound sample tested. (*2) The parenthesized value means the percentage of the released ClMIT (as the ratio of the released ClMIT to the total ClMIT in the fresh clathrate compound). From the test results, it has been confirmed that the release of Cl-MIT into water from the clathrate compound including it was significantly reduced. TEST EXAMPLE 3 To the clathrate compound produced in Example 2, containing Cl-MIT included with 4,4'-ethylidene-bisphenol, was added 2-bromo-2-nitro-1,3-propanediol in such an amout as indicated in Table 3 below. The resulting mixture was suspended in water at 60° C. in an amount of 1% by weight in terms of the concentration of Cl-MIT therein. Time-dependent variation in the free Cl-MIT concentration in water and that in the total Cl-MI concentration were measured. The results obtained are shown in Table 3. For comparison, the clathrate compound to which 2,2-2-bromo-2-nitro-1,3-propanediol had not been added was tested in the same manner as above, and the results obtained are also shown in Table 3. From Table 3, it is obvious that the addition of 2-bromo-2-nitro-1,3-propanediol resulted in the improvement in the stability of the Cl-MIT-including clathrate compound in water. TABLE 3______________________________________Amount of2-bromo-2-nitro- Total Free1,3-propanediol Cl-MIT Cl-MITNo. (wt. %) Time (wt. %) (ppm)______________________________________7 0.05 start 1.09 416 after 2 weeks 1.10 208 after 3 weeks 1.08 2348 0.02 start 1.11 412 after 2 weeks 1.09 184 after 3 weeks 1.08 2049 0.005 start 1.11 388 after 2 weeks 0 0 after 3 weeks 0 010 0 start 1.11 338 after 2 weeks 0 0 after 3 weeks 0 0______________________________________ As described in detail in the above, the clathrate compound of the present invention has a water-soluble microbicide clathrated by a phenolic compound, and it is helpful in powdering, stabilizing and concentrating the water-soluble microbicide therein. In addition, the present invention is also useful for separating and purifying water-soluble microbicides. Moreover, the present invention, thus providing a water-soluble microbicide as its clathrate compound, has the following advantages: (1) Since the active ingredient included in the clathrate compound may be slowly released into water from the compound, its microbicidal activity may be maintained for a prolonged period of time. (2) Since the compound is solid, it may be shaped into tablets, etc. Thus, the handling of the compound is easy. (3) Since the toxicity and the skin-stimulating property of the microbicide in the compound are lowered, the environment using the microbicide is improved and the safe use of the microbicide is ensured. (4) The thermal stability of the microbicide in the compound may be elevated, resulting in little thermal decomposition of the microbicide. (5) An active ingredient is prevented from reacting with any other substances to lower its microbicidal activity. Thus, the industrial importance of the present invention is obvious. In particular, the present invention preferably uses Cl-MIT as the water-soluble microbicide to be included in the clathrate compound, thus most advantageously displaying the effects. In addition, the clathrate compound of the present invention is extremely stable when used in the form of a microbicidal composition containing the compound along with a predetermined amount of a nitroalcoholic compound. While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.
A clathrate compound composed of a water-soluble microbicide and a phenolic compound of formula (1) or (2): ##STR1##
Provide a concise summary of the essential information conveyed in the given context.
[ "FIELD OF THE INVENTION AND RELATED ART STATEMENT The present invention relates to a clathrate compound and, more particularly, to a novel clathrate compound including a water-soluble microbicide, which improves the handleability and the stability of the microbicide therein.", "In water systems such as cooling water systems in various factory plants or the pulp and paper industries, slime of various bacteria, fungi, animals and vegetables adheres to the ducts or lines to cause various problems.", "Hitherto, for the purpose of preventing the problems caused by slime or the like in such systems, a microbicide (slime-controlling agent) has generally been employed as it is easily handled, and it is relatively inexpensive.", "For instance, 5-chloro-2-methyl-4-isothiazolin-3-one of the following formula (I) (hereinafter referred to as "Cl-MIT") is widely used as a slime-controlling agent, a bactericide, an algicide or a fungicide for various water systems such as a cooling water system, a papermaking process system or a swimming pool, as it has an excellent microbicidal activity.", "##STR2## However, Cl-MIT is extremely stimulative to the skin and caution is necessary when handling the same, though it has an excellent microbicidal activity.", "Since Cl-MIT decomposes extremely easily, water-soluble microbicides on the market contain a Large amount of Mg salts so as to stabilize Cl-MIT therein.", "Therefore, such commercial microbicides cannot be employed in the field of latex and emulsion which do not accept Mg salts.", "Cl-MIT can be separated from the water-soluble microbicides on the market by extraction methods using organic solvents, but the thus-extracted Cl-MIT is unstable especially under heat, so that it decomposes within one or two days even at a temperature of about 40° C. For these reasons, special storage conditions are necessary such as storing the compound in a refrigerator.", "In order to overcome problems such as above, the present applicant has already proposed clathrate compounds having a water-soluble microbicide such as Cl-MIT containing a host compound such as a bisphenol halide (Japanese Patent Laid-Open Publication No. 1-190602).", "Among the host compounds proposed in Japanese Patent Laid-Open Application No. 1-190602, 2,2'-methylenebis(4-chlorophenol) has been considered preferred.", "OBJECT AND SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved clathrate compound including a water-soluble microbicide such as Cl-MIT.", "The clathrate compound of the present invention is characterized by comprising a water-soluble microbicide and a phenolic compound of the following general formula (1) or (2): ##STR3## wherein R represents an alkylidene group having from 2 to 4 carbon atoms.", "##STR4## wherein each of R 1 and R 2 represents an alkyl group having from 2 to 4 carbon atoms.", "As the water-soluble microbicide, preferred is Cl-MIT having the above-mentioned structural formula (I).", "Specifically, the clathrate compound of the present invention is composed of a water-soluble microbicide such as Cl-MIT, as the guest compound, and the above-mentioned phenolic compound, as the host compound, wherein the host compound includes the guest compound therein.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS Bisphenolic compounds of formula (1) to be used in the present invention include, for example, 4,4'-ethylidenebisphenol, 2,4'-isopropylidenebisphenol, 2,2'-vinylidenebisphenol, 4,4'-isobutylidenebisphenol, 2,6'-sec-butylidenebisphenol, etc.", "Phenolic compounds of formula (2) also to be used in the present invention include, for example, 2,4-di-tert-butylphenol, 2,6-di-tert-butylphenol, 2,4-di-propylphenol, 2-propyl-4-tert-butylphenol, etc.", "The water-soluble microbicide for use in the present invention may be any one that may form a clathrate compound with the above-mentioned phenolic compound.", "Cl-MIT which is widely used as an effective microbicide is preferable, but this is not limitative.", "The clathrate compound of the present invention, comprising such a water-soluble microbicide and a phenolic compound, may easily be prepared by reacting them in an organic solvent or in water.", "When an organic solvent is used for preparing it, a solution, which is prepared by dissolving any of the above-mentioned phenolic compounds in an ordinary organic solvent such as methanol, ethanol or acetone is mixed with a water-soluble microbicide such as Cl-MIT or with a mixture containing a water-soluble microbicide such as Cl-MIT and some impurities, etc.", ", and reacted with the water-soluble microbicide.", "Accordingly, the intended clathrate compound precipitates out as a solid product, which is filtered and separated by ordinary methods.", "When water is used for the same, the above-mentioned phenolic compound is directly added to an aqueous solution containing a water-soluble microbicide as the guest compound, and mixed by stirring.", "The aqueous solution to be used is not limited to one containing only a water-soluble microbicide as the guest compound.", "As in the above-mentioned case using an organic solvent, the solution may contain some impurities.", "The above-mentioned phenolic compound reacts with a water-soluble microbicide with high selectivity.", "Therefore, even when a water-soluble microbicide containing impurities such as side products is used directly as the raw meterial, a desired clathrate compound including selectively only the intended water-solube microbicide is obtained.", "The reaction temperature may range from 0° C. to 100° C. In general, it is approximately from 10° C. to 30° C. The reaction time is from about 0.5 to 24 hours.", "After the reaction, the clathrate compound is generally obtained as a solid product, which may be separated from the aqueous phase, washed with water and dried.", "Thus, the intended clathrate compound of the present invention is obtained.", "The molar ratio between the water-soluble microbicide such as Cl-MIT and the above-mentioned phenolic compound of formula (1) both constituting the clathrate compound of the present invention, is generally such that (water-soluble microbicide):(phenolic compound (1)) is from 1:0.2to 1:5.", "The molar ratio between the water-soluble microbicide such as Cl-MIT and the above-mentioned phenolic compound of formula (2), both constituting the clathrate compound of the present invention, is generally such that (water-soluble microbicide):(phenolic compound(2) )is from 1:0.2to 1:5.", "The clathrate compound of the present invention, thus obtained in the manner mentioned above, is generally powdery and may easily be shaped into tablets.", "Since the water-soluble microbicide is included as the host compound, the clathrate compound is low in toxicity and is easily handled, and the microbicide is prevented from reacting with other substance to lower its microbicidal activity during its use.", "When the clathrate compound of the present invention is put into water, the water-soluble microbicide in the clathrate compound is released slowly therefrom.", "For example, when a clathrate compound of the present invention including 3% by weight of Cl-MIT therein is put into water, the amount of Cl-MIT to be released from the clathrate compound into water is as low as several 100 mg/liter.", "Therefore, a water-dispersible product containing a clathrate compound of the invention having the above-mentioned Cl-MIT concentration (3% by weight) is extremely preferred, as its stimulation to the skin is lessened.", "The compound of the present invention may be applied to a slow-release microbicide which slowly releases its active ingredient therefrom.", "Moreover, Since the clathrate compound of the present invention includes a water-soluble microbicide such as Cl-MIT as its guest compound, the microbicide therein is stabilized against heat.", "The clathrate compound of the present invention may be used, for example, according to the methods mentioned below.", "(1) The compound is packed in a column, and a liquid to be treated is passed therethrough.", "(2) The compound is put into a bag or a cartridge which is permeable to water but does not dissolve in water, and the bag or cartridge is dipped in or floated above water systems.", "(3) The compound of powder or tablet is dispersed in water systems.", "(4) The compound is mixed with coating compositions, resins, etc.", ", and the mixture is coated onto the surfaces of a device to be used in water systems, etc.", "(5) The compound is adhered to the surfaces of the objects to be protected, by any suitable means.", "It is preferred that the clathrate compound of the present invention is added to water to be treated in an amount of from 0.00001 to 0.5% by weight in terms of the concentration of the water-soluble microbicide such as Cl-MIT included in the clathrate compound.", "The stability of the clathrate compound of the present invention is often poor in water, when it is added with no other additive.", "When a nitroalcoholic compound is added to the clathrate compound of the present invention, then the stability of the compound in water may be elevated.", "The nitroalcoholic compound to be used for this purpose includes, for example, 2-chloro-2-nitro-ethanol, 1-chloro-1-nitro-2-propanol, 3-chloro-3-nitro-2-butanol, 2-chloro-2-nitro-1,3-butanediol, 1-chloro-1-nitro-2-butanol, 2-chloro-2-nitro-butanol, 2-chloro-2-nitro-3-pentanol, 2,2-dichrolo-2-nitro-ethanol, 2-bromo-2-chloro-2-nitro-ethanol, 3-chrolo-3-nitro-2,4-pentanediol, 4-chrolo-4-nitro-3-hexanol, 2-bromo-2-nitro-ethanol, 2-bromo-2-nitro-3-propanol, 2-bromo-2-nitro-1,3-butanediol, 3-bromo-3-nitro-2,4-pentanediol, 2,2-dibromo-2-nitro-ethanol, 1,1-dibromo-1-nitro-2-propanol, 4-bromo-4-nitro-3-hexanol, 2-fluoro-2-nitro-ethanol, 2-fluoro-2-nitro-1,3-butanediol, 3-Iodo-3-nitro-2-butanol, 2-chloro-2-fluoro-2-nitro-ethanol, 2-bromo-2-Iodo-2-nitro-ethanol, 2-chloro-2-nitro-1,3-propanediol, 2-bromo-2-nitro-1,3-propanediol.", "The amount of the compound to be added to the clathrate compound of the present invention is preferably from 0.1 to 5% by weight relative to the clathrate compound.", "If it is less than 0.1% by weight, a sufficient stabilizing effect cannot be attained.", "However even if it is more than 5% by weight, no difference in the stability-improving effect will be observed and therefore, such excess addition is not economical.", "When a microbicidal composition comprising the clathrate compound of the present invention and such a nitroalcoholic compound is added to water to be treated therewith, it is preferred that the amount of the composition to be added is approximately from 0.00001 to 0.5% by weight in terms of the concentration of the water-soluble microbicide in the composition.", "The clathrate compound of the present invention is helpful in powdering, stabilizing and concentrating the water-soluble microbicide included therein.", "In addition, since the clathrate compound of the present invention is a reaction product having high selectivity in particular compounds, it may also be used for separating and purifying particular water-soluble microbicides.", "For instance, Cl-MIT may be separated from a mixture comprising Cl-MIT and its side-product of 2-methyl-4-isothiazolin-3-one (hereinafter referred to as "MI"), though such separation has heretofore been difficult.", "This is accomplished by making only Cl-MIT selectively included in a host compound to give a clathrate compound, and then by separating the thus-included Cl-MIT from the clathrate compound.", "In this way, a high-purity Cl-MIT may be isolated from the mixture.", "To separate a water-soluble microbicide such as Cl-MIT from the clathrate compound including it, the following methods may be employed.", "(1) The clathrate compound is dipped in water.", "(2) The clathrate compound is dissolved in an organic solvent and then water is added thereto, whereby only the host compound is made precipitated.", "According to these methods, the water-soluble microbicide included in the clathrate compound dissolves out into water, and it is recovered as its aqueous solution.", "When a water-soluble microbicide is formed into a clathrate compound with the above-mentioned phenolic compound acting as the host compound, according to the present invention, it becomes solid so that its handleability is much improved.", "In addition, the dissolution of the microbicide component into water from the clathrate compound is significantly lowered, and the toxicity and the skin-stimulating property of the microbicide are reduced.", "Moreover, the microbicide in the clathrate compound is prevented from reacting with any other substance to lower its microbicidal activity during its use.", "Further, the heat-resistant stability of the microbicide is improved, as it is included in the clathrate compound.", "For these reasons, the clathrate compound of the present invention may be used effectively as a slow-release microbicide whereby the microbicidal activity may be maintained for a long period of time.", "In addition, since the clathrate compound of the present invention is helpful in powdering, stabilizing and concentrating the water-soluble microbicide therein and since the host compound selectively includes the water-soluble microbicide therein, the present invention is also useful for separating and purifying water-soluble microbicides.", "In particular, when Cl-MIT is used as the water-soluble microbicide, the present invention provides an excellent microbicidal product.", "Preferably, the clathrate compound of the present invention is most stable when used in the form of a microbicidal composition containing the compound along with a predetermined amount of a nitroalcoholic compound.", "The present invention will be described in more detail by means of the following examples, which are not intended to restrict the scope of the present invention.", "EXAMPLE 1 Production of Clathrate Compound of Cl-MIT and 2,4-Di-Ter-Butylphenol (by Methanol Solvent Method) 500 g of a water-soluble microbicide consisting essentially of Cl-MIT (Cl-MIT concentration: 10.4% by weight) were extracted with 200 g of chloroform, and the solvent in the chloroform layer was removed by distillation to separate Cl-MIT.", "The yield was 50 g, and the product contained 2 to 3% by weight of MI.", "0.69 g (3.34 mmol) of 2,4-di-tert-butylphenol were put int a sample bottle and dissolved in 10 ml of methanol therein.", "0.5 g (3.34 mmol) of the previously separated Cl-MIT were added thereto and mixed.", "After mixing, the mixture was left as it was, thereby removing the solvent thererfrom by natural drying to make crystals precipitated.", "The thus-obtained crystals were separated, washed with 2 ml of water and then dried.", "The product was analyzed by IR spectrography and NMR spectrography, and the Cl-MIT content in the product was measured by HPLC.", "As a result, the product was identified to be a clathrate compound of 2,4-di-tert-butylphenol/Cl-MIT of nearly 2/1 (by mol), having a Cl-MIT content of 25.83% by weight.", "EXAMPLE 2 Production of Clathrate Compound of Cl-MIT and 4,4'-Ethylidene-Bisphenol (By Methanol Solvent Method) The same process as in Example 1 was repeated, except that 0.5 g (3.34 mmol) of Cl-MIT and the same molar amount of 4,4'-ethylidene-bisphenol were used, and the product was analyzed in the same manner as in Example 1.", "The product was identified to be a clathrate compound of 4,4'-ethylidene-bisphenol/Cl-MIT of nearly 1/1 (by mol), having a Cl-MIT content of 37.84% by weight.", "EXAMPLE 3 Production of Clathrate Compound of Cl-MIT and 2,4-Di-Tert-Butylphenol (By Water Solvent Method) 1.436 g (6.95 mmol) of 2,4-di-tert-butylphenol and 10 g of an aqueous microbicidal solution consisting essentially of Cl-MIT (Cl-MIT concentration: 10.4% by weight, Cl-MIT content: 1.04 g (6.95 mmol)) were mixed and reacted, and left overnight.", "The crystals thus formed were separated from the aqueous layer, washed with 2 ml of water and then dried.", "The product was analyzed by IR spectrography and NMR spectrography, and the Cl-MIT content in the product was measured by HPLC.", "As a result, the product was identified to be a clathrate compound of 2,4-di-tert-butylphenol/Cl-MIT of nearly 2/1, having a Cl-MIT content of 25.8% by weight.", "TEST EXPERIMENT 1 Test for Thermal Stability (at 40° C.) of Cl-MIT In Its Clathrate Compound 10 g of each of the clathrate compounds obtained by the methanol solvent method in Examples 1 and 2 were put into a screw-cap bottle, which was then sealed.", "These bottles were set in a thermostat at 40° C. At intervals, the content in each bottle was sampled and analyzed by HPLC to determine the Cl-MIT content in the clathrate compound.", "From the data measured and the initial Cl-MIT content in the fresh compound, the retention percentage of Cl-MIT remained in the sampled clathrate compound was obtained.", "The results are shown in Table 1 below.", "For comparison, only Cl-MIT was tested in the same manner as above to obtain the retention percentage thereof.", "The results are also shown in Table 1.", "TABLE 1______________________________________ Retention Percentage of Cl-MIT (%) Molar Ratio initial after afterNo.", "Host Compound (guest/host) value 1 week 1 month______________________________________1 2,4-Di-tert- 1/2 100.0 97.6 97.2butylphenol2 4,4'-Ethylidene- 1/1 100.0 96.2 96.5bisphenol3 (Cl-MIT in the -- 100.0 0.0 0.0nude)______________________________________ From the test results, it has been confirmed that Cl-MIT in the nude blackened and decomposed in one week while the clathrate compound including Cl-MIT did not.", "TEST EXPERIMENT 2 Measurement of Cl-MIT Released into Water (at 25° C.) From Clathrate Compound Including It Each of the clathrate compounds obtained in Examples 1 and 2 was mixed with water to prepare an aqueous mixture having a Cl-MIT concentration of 3% by weight.", "The thus-prepared mixtures were kept in a thermostat tank at 25° C. and sampled at intervals.", "Each sample was passed through a 0.45 μm-millipore filter to thereby separate the clathrate compound from the aqueous phase.", "Then, the Cl-MIT concentration in the thus-separated aqueous phase was measured by HPLC, from which the amount of Cl-MIT released into water was determined.", "The amount of the clathrate compound tested, the amount of water added to the compound, and the amount of Cl-MIT released into water are shown in Table 2.", "For comparison, only Cl-MIT was tested in the same manner as above to obtain its amount dissolved in water.", "The results are also shown in Table 2.", "TABLE 2__________________________________________________________________________ Cl-MIT Cl-MIT Amount of Cl-MIT Amount (g) Concentration Concentration Released into Water (mg/liter)(*2) Host Clathrate in Sample in Water after after after afterNo.", "Compound Compound Water (wt.", "%) (mg/liter)(*1) 1 day 1 week 3 weeks 1__________________________________________________________________________ month4 2,4-Di-tert- 5.784 44.223 3 33940 721 700 681 664 butylphenol (21.", "%) (21%) (2.0%) (2.0%) (Cl-MIT content: 25.83 wt.", "%)5 4,4'- 3.137 36.829 3 32564 335 327 351 330 Ethylidene- (1.0%) (1.0%) (1.1%) (1.0%) bisphenol (Cl- MIT content: 37.84 wt.", "%)6 Cl-MIT 30000 (100%)__________________________________________________________________________ (*1) This means the ClMIT concentration in water, resulting from complete release of all ClMIT from the clathrate compound sample tested.", "(*2) The parenthesized value means the percentage of the released ClMIT (as the ratio of the released ClMIT to the total ClMIT in the fresh clathrate compound).", "From the test results, it has been confirmed that the release of Cl-MIT into water from the clathrate compound including it was significantly reduced.", "TEST EXAMPLE 3 To the clathrate compound produced in Example 2, containing Cl-MIT included with 4,4'-ethylidene-bisphenol, was added 2-bromo-2-nitro-1,3-propanediol in such an amout as indicated in Table 3 below.", "The resulting mixture was suspended in water at 60° C. in an amount of 1% by weight in terms of the concentration of Cl-MIT therein.", "Time-dependent variation in the free Cl-MIT concentration in water and that in the total Cl-MI concentration were measured.", "The results obtained are shown in Table 3.", "For comparison, the clathrate compound to which 2,2-2-bromo-2-nitro-1,3-propanediol had not been added was tested in the same manner as above, and the results obtained are also shown in Table 3.", "From Table 3, it is obvious that the addition of 2-bromo-2-nitro-1,3-propanediol resulted in the improvement in the stability of the Cl-MIT-including clathrate compound in water.", "TABLE 3______________________________________Amount of2-bromo-2-nitro- Total Free1,3-propanediol Cl-MIT Cl-MITNo.", "(wt.", "%) Time (wt.", "%) (ppm)______________________________________7 0.05 start 1.09 416 after 2 weeks 1.10 208 after 3 weeks 1.08 2348 0.02 start 1.11 412 after 2 weeks 1.09 184 after 3 weeks 1.08 2049 0.005 start 1.11 388 after 2 weeks 0 0 after 3 weeks 0 010 0 start 1.11 338 after 2 weeks 0 0 after 3 weeks 0 0______________________________________ As described in detail in the above, the clathrate compound of the present invention has a water-soluble microbicide clathrated by a phenolic compound, and it is helpful in powdering, stabilizing and concentrating the water-soluble microbicide therein.", "In addition, the present invention is also useful for separating and purifying water-soluble microbicides.", "Moreover, the present invention, thus providing a water-soluble microbicide as its clathrate compound, has the following advantages: (1) Since the active ingredient included in the clathrate compound may be slowly released into water from the compound, its microbicidal activity may be maintained for a prolonged period of time.", "(2) Since the compound is solid, it may be shaped into tablets, etc.", "Thus, the handling of the compound is easy.", "(3) Since the toxicity and the skin-stimulating property of the microbicide in the compound are lowered, the environment using the microbicide is improved and the safe use of the microbicide is ensured.", "(4) The thermal stability of the microbicide in the compound may be elevated, resulting in little thermal decomposition of the microbicide.", "(5) An active ingredient is prevented from reacting with any other substances to lower its microbicidal activity.", "Thus, the industrial importance of the present invention is obvious.", "In particular, the present invention preferably uses Cl-MIT as the water-soluble microbicide to be included in the clathrate compound, thus most advantageously displaying the effects.", "In addition, the clathrate compound of the present invention is extremely stable when used in the form of a microbicidal composition containing the compound along with a predetermined amount of a nitroalcoholic compound.", "While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing failure judging apparatus and more particularly, to an apparatus for judging the type of a failure occurring in a bearing. 2. Description of the Prior Art A conventional apparatus is shown in block form in FIG. 1. A sensor/amplifier section (1) detects the vibration of a bearing (not shown) and amplifies the detected signal. The output signal from the sensor/amplifier section (1) is applied to an effective value detecting section (2) where the effective value of the output signal is detected and also to the peak value detecting section (3) where a peak value thereof is detected. The effective value detected is compared with a set value previously set in an effective value comparator (4) to judge whether the effective value is normal or not. Similarly, the peak value detected is compared with a set value previously set in a peak value comparator (5) to judge whether the peak value is normal or not. A judging section (6) judges on the basis of the results of the comparisons whether the bearing has failed. A display section (7) displays the result of the judgement by the judging section (6). When the judging apparatus described above determines that the bearing is abnormal, the judging apparatus encounters many problems in seeking what type of failure renders the bearing abnormal. The first problem is involved in the values obtained by the effective value and peak value detecting sections. Particularly the peak value varies largely with the frequency components of the waveform of the detected signal, possibly leading to an error of the peak value. The second problem is the erroneous operation of the judging apparatus. Generally, the bearing failure judging apparatus is with coupled to a dynamically operating equipment containing the bearing, so that pulsate waves occurring at the start and the stop of the equipment or disturbances caused during maintenance, drive the judging apparatus as if a failure is present in the bearing. The third problem is involved with the discriminating ability of the judging apparatus for discriminating the cause of the failure. There is a suggestion that the cause of the failure due to scars or other causes may be quantitatively judged on the basis of the ratio of the effective value to the peak value. The suggestion lacks a quantitative analysis and therefore the judgement thereby is frequently erroneous. In order to solve these problems, the following prior art (Japanese Patent Application No. 4531/1978) has been proposed and has solved some of the problems successfully. The prior art will be described in reference to FIG. 2. As shown, a sensor/amplifier section (1) is connected at the output to a low-pass filter (8) which is further connected at the output to an A/D converter (9). A control section (10) is connected to a memory section (11) and an arithmetic logic section (12) is connected at the output to a display section (7). In the device shown in FIG. 2 which is designed to the sense scars of a bearing, a signal wave is digitized by the A/D converter (9), controlled by the control section (10), loaded into or read out from the memory section (11), and applied to the arithmetic logic section (12) where it is subjected to a Fourier conversion to extract features of the sensed signal in the frequency domain. Through the processings, the kind and a degree of the scars occuring at the respective portions of the bearing are classified and analyzed and then displayed in the display section (7). The judging apparatus thus described provides very useful data of a specific failure, or the scar of the bearing. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an apparatus which judges and displays the type of a cause of a failure occurring in a bearing before the failure develops to seize or destroy the bearing, thus possibly leading to disastrous accident. Briefly, in the apparatus according to the invention, a detected signal wave detected from a bearing is lead to a time domain extracting means and a frequency domain extracting means in order to extract features of the detected signal wave in the time domain and features thereof in the frequency domain. Through the processings of those means, the type of the cause of a failure of the bearing is judged. If necessary, the detected signal is amplified by amplifying means and the amplified signal is led through a low-pass filter to an A/D converter. The digital signal produced from the A/D converter is led to the time domain extracting means and the frequency domain extracting means. Other objects and features of the invention will be apparent from the following description taken in connection with the accompanying drawings, in which: BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a block diagram of a conventional failure judging apparatus; FIG. 2 shows a block diagram of a judging apparatus for judging scars of a rolling bearing, which was proposed for solving the problems involved in the apparatus shown in FIG. 1; FIG. 3, comprising FIGS. 3(a)-3(d), shows graphs illustrating some combinations of the time waveforms and the related frequency spectra, which are peculiar to the types of the failures of the bearing, respectively; FIG. 4 shows a block diagram of an embodiment of a bearing failure judging apparatus according to the invention; FIG. 5 shows a block diagram of an embodiment of a bearing failure judging apparatus according to the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As is known, various types of failures occur in a bearing, each being attendant with a specific vibration. The vibration of the bearing with a failure will be described for each type of failure of before proceeding with description of the bearing failure judging apparatus of the present invention. Many experiments and the long experience of the inventors teach that most of failures of the bearing occurring in a normal use may be classified into the following three conditions: (1) seizure coming from a lubricating oil shortage, (2) presence of foreign matters, and (3) scars marked on the respective portions of the bearing. Typical time-waveforms and frequency spectra of these three kinds of failures will be illustrated on the left and right sides in FIG. 3. FIG. 3(a) illustrates a vibration acceleration waveform and a frequency spectrum when a bearing is normal. As seen, the output voltage of the time-waveform is small and the level of the frequency spectrum is low. FIG. 3(b) shows an output voltage when there is shortage of an oil. A seizure due to a slight shortage of oil causes a great voltage change, say, 3 to 5 times that of the normal output voltage. The frequency spectrum in this case is analogous to that obtained as the result of the analysis of white noise. FIG. 3(c) illustrates the condition when foreign matter is mixed into the lubricating oil. In this case, foreign matter put between the rolling surface and the balls, produce pulsate waveforms. The pulsate waves are random in the amplitudes and the intervals of their occurrences. The frequency spectrum takes an indefinite shape due to the pulsate waves and the irregular waveform follwoing the pulsate wave, similar to the case of an oil shortage. FIG. 3(d) shows a waveform and a frequency spectrum when the bearing is scarred. As shown, pulsate waves occure at fixed periods and substantially fixed amplitude. The pulsate waves induce a resonant vibration in the portion marked with the scar of the bearing, so that marked proper peaks appear in the frequency spectrum. An additional feature of the time-waveform is a localization of the amplitudes of the wave. The cause of the localization is unapparent, however, it is estimated that the localization arises from a nonlinearity characteristic of the vibration system. This phenomenon of the localization is observed very frequently in rolling bearings. An embodiment of the invention was made on the basis of findings described above. Referring now to FIG. 4 and FIG. 5, there is shown a failure judging apparatus according to the present invention. As shown, a sensor/amplifier section (1) consisting of a sensor (101) and an amplifier (102) with the same construction as that of FIG. 1 is connected at the output to an A/D converter (9) by way of a low-pass filter (8). The output of the A/D converter (9) is coupled with a time-domain operation section (13) and a frequency-domain operation section (14). The time-domain operation section (13) comprises a memory (121) for memorizing waveform; an envelope forming device (108); RMS detector (109) for outputs of the envelope forming device (108); a detector (110) for detecting localization to +side or -side to zero level; an envelope peak detector (111); an impulse wave width detector (112); and a memory (113) for memorizing the value of (109). The time-domain judging section (15) comprises comparators (114), (115), (116), (117) which respectively correspond to the devices (109), (110), (111) and (112) and a comparator (118) which determines, in total, the results of the comparators (114), (115), (116) and (117). The frequency domain operation section (14) comprises a fast Fourier converter (119); a frequency variation detector (120) which detects variation of the output of (119) and the waveform memory (121). Further, the time-domain section (13) is coupled at the output with a time-domain judging section (15) and the frequency-domain section (14) with a frequency-domain section (16). A judging section (6), receiving the output signals from those judging sections (15) and (16), is provided as a subsequent stage. A display section (7) provided following the judging section (6) displays the type of failure. At the output side of the display section (7), an output section (17) is further provided to transmit a signal to a bearing failure-restoring direction unit (not shown) to direct one to restore the failed bearing. The operation of the bearing failure judging apparatus as described above will be described. A vibration occurring in the bearing is sensed and amplified by the sensor/amplifier section (1) and the sensed and amplified signal representing the vibration is fed into the low-pass filter (8) to prevent errors and then is inputted into the A/D converter (9) where it is converted from the analog form into digital form. The speed of the A/D conversion is limited by the upper limit of the frequency of the vibration occurring in the bearing to be judged, usually 20,000 per second. The number of conversion of a train of Generally the one defined by 2 n under consideration of the operation algorithm of the fast Fourier conversion used when the frequency spectrum is obtained, the number of quantitized signals is generally the one defined by 2 n ; usually n=8 to 10, say, 256 to 1024. The first step of the processings in the time domain operation section (15) and the judging section is to obtain an envelope of the waveform. The envelope may be obtained merely by connecting the positive and negative peaks of the waveform by the envelope forming device (108), for example, since the waveform is already quantitized. Let us express generally the envelope function as E(iΔt) where Δt is the interval of the time waveform and the envelope on the positive side is E + (iΔt) and that on the negative side is E - (iΔt) where i=0 to N -1 and N =10 n . Then, let us extract the feature of the time waveform by using the general envelope expression E(iΔt). Firstly, whether or not some failure takes place in the bearing may be checked by using, for example, a bearing failure alarm device to warn that there is a high possibility that some failure is now occurring in the bearing. This also may be vertified by the amplitude of E(iΔt) detected by the detector (111). When a reference value in a normal state or previously set by the comparator (116), [E(iΔt)]s, satisfies the following relations, it is considered that a failure takes place in the bearing. E.sup.+ (IΔt)≧[E.sup.+ (iΔt)]s E.sup.- (iΔt)≦[E.sup.- (iΔt)]s (1) Following this, to classify the cause of the failure into types, the thickness of the time waveform detected by the width detector (112) is investigated by using the envelope function. The accumulated value of the envelope function is defined as follows: ##EQU1## Then the following expression is calculated. Q=Q.sup.+ -Q.sup.- (3) By comparing the Q which is set by the comparator (117) and is obtained with the set value Qs, we can know the cause of the failure of the bearing: when Q≧Qs, the cause is a shortage of the lubricating oil or mixing of foreign substances into the lubricating oil; when Q<Qs, the causes is scars marked on the bearing. Thirdly, the period of peaks appearing found in the envelope function is obtained. The period T is given T˜Ts (4) where Ts is a fixed value defined by the size of the bearing. When T approximates Ts, there is a possibility that the scar is marked somewhere on the bearing. Then, in order to determine by the localization detector (110) where the pulsate peaks are localized, the following relation is investigated about the peak values in the envelope function: |E.sup.+ (pΔt)/E.sup.- (pΔt)|≧S (5) where P=the value of i when peaks appear in the envelope function and S=a set value of the comparator (115)˜1.5. If the equation (5) is satisfied, a possibility that the bearing is scarred increases. The processing in the frequency-domain operation section (14) and the frequency-domain judging section (16) are performed according to the following equations (6) and (7) by the fast Fourier converter (119). The original waveform is quantitized as x(iΔt) and then the following expression is operated: ##EQU2## where X(kΔf)=Fourier conversion of x(iΔt) f=divided frequency intervals of Fourier spectrum obtained k=0 to N-1 j=√-1 Following this operation, the power spectrum of P(kΔf) expressed by the following equation (7) is operated to obtain the frequency spectrum. P(kΔf)=X(kΔf)·X*(kΔf) (7) where P(kΔf)=the power spectrum of X(kΔf) X*(kΔf)=the conjugate complex number of X(kΔf). The operation of the expression (6) may easily be performed for a short time by using the algorithm of the usual fast Fourier conversion. The frequency spectrum obtained is investigated to determine if there is a peak in a specific frequency or not and whether a level is large or not over a wide frequency range the frequency variation detector (120). The result of the investigation is classified into two cases: (1) scars of the bearing, (2) the mixing of foreign substances into the lubricating oil or a shortage of oil. The judging section receives all the results of those operations and properly weights the result of the judgement, thereby to provide the synthetic judgement by the comparator (6). If the cause of the failure is the shortage of the oil or the mixing of foreign substances, a sequence of those processings are performed once and then the same sequence is repeated after a given time. For example, when an increase of the envelope function, more or simply an increase of the effective value of the time waveform is large, in comparison of the present effective value detected by the effective value RMS detector (109) with effective values memorized in the memory (113) before certain times, the failure is determined to be a mixing of foreign substances. Conversely, when it is small, the cause of the failure is a shortage of oil. Depending on the number of the bearings to be examined, the given time is usually 30 minutes to one hour. In this case, the rate of increase of the effective value when foreign substances are mixed into the lubricating oil is 7 to 10 times, compared to the effective value when the bearing is normal. However, in the case of oil shortage, the rate of increase is 2 to 3 times at most. The operations and judgement processes of the signal quantitized are executed by using a microprocessor. The use of the microprocessor is considered to be most suitable for these processings in the light of the cost, the use condition and the flexibility in the application of the microprocessor. The display section reports the result of the judgement to an operator or monitor personel while at the same time it applies the outputs to the output section. Each of the above noted components above discussed in connection with the disclosure of FIG. 5, as well as the other FIGUREs, are readily available in the marketplace. By way of examples only, memory 121 can be implemented by any available memory such as ROM or RAM manufactured by MELCO, in particular type M5L2716K, M5L 2732K, etc. Memory 113 can likewise be constructed using conventional memory circuits. Comparators 114-118 can be implemented of any of commercially available microprocessors, such as the 8085 type microprocessor. Fast Fourier converter 119 can be constructed using conventional Fast Fourier conversion algorithms, as for example disclosed in Cochran et al, "What is the Fast Fourier Transformer", IEEE Trans. on Audio and Electroacoustics, Vol. AV-15, No. 2, June, 1967, pp. 45-55. In the above-mentioned embodiment, a vibration is used as a signal to extract a failure, however, any other suitable medium to report a failure of the bearing may be used. For example, an acoustic signal may be very effective to sense the failure of the bearing. In this case, the sensor is a microphone.
A bearing failure judging apparatus correctly judges the type of the cause of a failure of a bearing by synthetically judging many factors found in a vibrating waveform of a vibration produced when a failure takes place in the bearing i.e. various features of the time-waveform; a localization of the amplitudes of the time-waveform, the periods of pulsating waves, a degree of the acuteness of the waveform depicted by its envelope, the presence or absence of the proper peak value in the frequency spectra, and a change of the waveform after a given time.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to a bearing failure judging apparatus and more particularly, to an apparatus for judging the type of a failure occurring in a bearing.", "Description of the Prior Art A conventional apparatus is shown in block form in FIG. 1. A sensor/amplifier section (1) detects the vibration of a bearing (not shown) and amplifies the detected signal.", "The output signal from the sensor/amplifier section (1) is applied to an effective value detecting section (2) where the effective value of the output signal is detected and also to the peak value detecting section (3) where a peak value thereof is detected.", "The effective value detected is compared with a set value previously set in an effective value comparator (4) to judge whether the effective value is normal or not.", "Similarly, the peak value detected is compared with a set value previously set in a peak value comparator (5) to judge whether the peak value is normal or not.", "A judging section (6) judges on the basis of the results of the comparisons whether the bearing has failed.", "A display section (7) displays the result of the judgement by the judging section (6).", "When the judging apparatus described above determines that the bearing is abnormal, the judging apparatus encounters many problems in seeking what type of failure renders the bearing abnormal.", "The first problem is involved in the values obtained by the effective value and peak value detecting sections.", "Particularly the peak value varies largely with the frequency components of the waveform of the detected signal, possibly leading to an error of the peak value.", "The second problem is the erroneous operation of the judging apparatus.", "Generally, the bearing failure judging apparatus is with coupled to a dynamically operating equipment containing the bearing, so that pulsate waves occurring at the start and the stop of the equipment or disturbances caused during maintenance, drive the judging apparatus as if a failure is present in the bearing.", "The third problem is involved with the discriminating ability of the judging apparatus for discriminating the cause of the failure.", "There is a suggestion that the cause of the failure due to scars or other causes may be quantitatively judged on the basis of the ratio of the effective value to the peak value.", "The suggestion lacks a quantitative analysis and therefore the judgement thereby is frequently erroneous.", "In order to solve these problems, the following prior art (Japanese Patent Application No. 4531/1978) has been proposed and has solved some of the problems successfully.", "The prior art will be described in reference to FIG. 2. As shown, a sensor/amplifier section (1) is connected at the output to a low-pass filter (8) which is further connected at the output to an A/D converter (9).", "A control section (10) is connected to a memory section (11) and an arithmetic logic section (12) is connected at the output to a display section (7).", "In the device shown in FIG. 2 which is designed to the sense scars of a bearing, a signal wave is digitized by the A/D converter (9), controlled by the control section (10), loaded into or read out from the memory section (11), and applied to the arithmetic logic section (12) where it is subjected to a Fourier conversion to extract features of the sensed signal in the frequency domain.", "Through the processings, the kind and a degree of the scars occuring at the respective portions of the bearing are classified and analyzed and then displayed in the display section (7).", "The judging apparatus thus described provides very useful data of a specific failure, or the scar of the bearing.", "SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an apparatus which judges and displays the type of a cause of a failure occurring in a bearing before the failure develops to seize or destroy the bearing, thus possibly leading to disastrous accident.", "Briefly, in the apparatus according to the invention, a detected signal wave detected from a bearing is lead to a time domain extracting means and a frequency domain extracting means in order to extract features of the detected signal wave in the time domain and features thereof in the frequency domain.", "Through the processings of those means, the type of the cause of a failure of the bearing is judged.", "If necessary, the detected signal is amplified by amplifying means and the amplified signal is led through a low-pass filter to an A/D converter.", "The digital signal produced from the A/D converter is led to the time domain extracting means and the frequency domain extracting means.", "Other objects and features of the invention will be apparent from the following description taken in connection with the accompanying drawings, in which: BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a block diagram of a conventional failure judging apparatus;", "FIG. 2 shows a block diagram of a judging apparatus for judging scars of a rolling bearing, which was proposed for solving the problems involved in the apparatus shown in FIG. 1;", "FIG. 3, comprising FIGS. 3(a)-3(d), shows graphs illustrating some combinations of the time waveforms and the related frequency spectra, which are peculiar to the types of the failures of the bearing, respectively;", "FIG. 4 shows a block diagram of an embodiment of a bearing failure judging apparatus according to the invention;", "FIG. 5 shows a block diagram of an embodiment of a bearing failure judging apparatus according to the invention.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As is known, various types of failures occur in a bearing, each being attendant with a specific vibration.", "The vibration of the bearing with a failure will be described for each type of failure of before proceeding with description of the bearing failure judging apparatus of the present invention.", "Many experiments and the long experience of the inventors teach that most of failures of the bearing occurring in a normal use may be classified into the following three conditions: (1) seizure coming from a lubricating oil shortage, (2) presence of foreign matters, and (3) scars marked on the respective portions of the bearing.", "Typical time-waveforms and frequency spectra of these three kinds of failures will be illustrated on the left and right sides in FIG. 3. FIG. 3(a) illustrates a vibration acceleration waveform and a frequency spectrum when a bearing is normal.", "As seen, the output voltage of the time-waveform is small and the level of the frequency spectrum is low.", "FIG. 3(b) shows an output voltage when there is shortage of an oil.", "A seizure due to a slight shortage of oil causes a great voltage change, say, 3 to 5 times that of the normal output voltage.", "The frequency spectrum in this case is analogous to that obtained as the result of the analysis of white noise.", "FIG. 3(c) illustrates the condition when foreign matter is mixed into the lubricating oil.", "In this case, foreign matter put between the rolling surface and the balls, produce pulsate waveforms.", "The pulsate waves are random in the amplitudes and the intervals of their occurrences.", "The frequency spectrum takes an indefinite shape due to the pulsate waves and the irregular waveform follwoing the pulsate wave, similar to the case of an oil shortage.", "FIG. 3(d) shows a waveform and a frequency spectrum when the bearing is scarred.", "As shown, pulsate waves occure at fixed periods and substantially fixed amplitude.", "The pulsate waves induce a resonant vibration in the portion marked with the scar of the bearing, so that marked proper peaks appear in the frequency spectrum.", "An additional feature of the time-waveform is a localization of the amplitudes of the wave.", "The cause of the localization is unapparent, however, it is estimated that the localization arises from a nonlinearity characteristic of the vibration system.", "This phenomenon of the localization is observed very frequently in rolling bearings.", "An embodiment of the invention was made on the basis of findings described above.", "Referring now to FIG. 4 and FIG. 5, there is shown a failure judging apparatus according to the present invention.", "As shown, a sensor/amplifier section (1) consisting of a sensor (101) and an amplifier (102) with the same construction as that of FIG. 1 is connected at the output to an A/D converter (9) by way of a low-pass filter (8).", "The output of the A/D converter (9) is coupled with a time-domain operation section (13) and a frequency-domain operation section (14).", "The time-domain operation section (13) comprises a memory (121) for memorizing waveform;", "an envelope forming device (108);", "RMS detector (109) for outputs of the envelope forming device (108);", "a detector (110) for detecting localization to +side or -side to zero level;", "an envelope peak detector (111);", "an impulse wave width detector (112);", "and a memory (113) for memorizing the value of (109).", "The time-domain judging section (15) comprises comparators (114), (115), (116), (117) which respectively correspond to the devices (109), (110), (111) and (112) and a comparator (118) which determines, in total, the results of the comparators (114), (115), (116) and (117).", "The frequency domain operation section (14) comprises a fast Fourier converter (119);", "a frequency variation detector (120) which detects variation of the output of (119) and the waveform memory (121).", "Further, the time-domain section (13) is coupled at the output with a time-domain judging section (15) and the frequency-domain section (14) with a frequency-domain section (16).", "A judging section (6), receiving the output signals from those judging sections (15) and (16), is provided as a subsequent stage.", "A display section (7) provided following the judging section (6) displays the type of failure.", "At the output side of the display section (7), an output section (17) is further provided to transmit a signal to a bearing failure-restoring direction unit (not shown) to direct one to restore the failed bearing.", "The operation of the bearing failure judging apparatus as described above will be described.", "A vibration occurring in the bearing is sensed and amplified by the sensor/amplifier section (1) and the sensed and amplified signal representing the vibration is fed into the low-pass filter (8) to prevent errors and then is inputted into the A/D converter (9) where it is converted from the analog form into digital form.", "The speed of the A/D conversion is limited by the upper limit of the frequency of the vibration occurring in the bearing to be judged, usually 20,000 per second.", "The number of conversion of a train of Generally the one defined by 2 n under consideration of the operation algorithm of the fast Fourier conversion used when the frequency spectrum is obtained, the number of quantitized signals is generally the one defined by 2 n ;", "usually n=8 to 10, say, 256 to 1024.", "The first step of the processings in the time domain operation section (15) and the judging section is to obtain an envelope of the waveform.", "The envelope may be obtained merely by connecting the positive and negative peaks of the waveform by the envelope forming device (108), for example, since the waveform is already quantitized.", "Let us express generally the envelope function as E(iΔt) where Δt is the interval of the time waveform and the envelope on the positive side is E + (iΔt) and that on the negative side is E - (iΔt) where i=0 to N -1 and N =10 n .", "Then, let us extract the feature of the time waveform by using the general envelope expression E(iΔt).", "Firstly, whether or not some failure takes place in the bearing may be checked by using, for example, a bearing failure alarm device to warn that there is a high possibility that some failure is now occurring in the bearing.", "This also may be vertified by the amplitude of E(iΔt) detected by the detector (111).", "When a reference value in a normal state or previously set by the comparator (116), [E(iΔt)]s, satisfies the following relations, it is considered that a failure takes place in the bearing.", "E.sup.", "+ (IΔt)≧[E.", "sup.", "+ (iΔt)]s E.sup.", "- (iΔt)≦[E.", "sup.", "- (iΔt)]s (1) Following this, to classify the cause of the failure into types, the thickness of the time waveform detected by the width detector (112) is investigated by using the envelope function.", "The accumulated value of the envelope function is defined as follows: ##EQU1## Then the following expression is calculated.", "Q=Q.", "sup.", "+ -Q.", "sup.", "- (3) By comparing the Q which is set by the comparator (117) and is obtained with the set value Qs, we can know the cause of the failure of the bearing: when Q≧Qs, the cause is a shortage of the lubricating oil or mixing of foreign substances into the lubricating oil;", "when Q<Qs, the causes is scars marked on the bearing.", "Thirdly, the period of peaks appearing found in the envelope function is obtained.", "The period T is given T˜Ts (4) where Ts is a fixed value defined by the size of the bearing.", "When T approximates Ts, there is a possibility that the scar is marked somewhere on the bearing.", "Then, in order to determine by the localization detector (110) where the pulsate peaks are localized, the following relation is investigated about the peak values in the envelope function: |E.", "sup.", "+ (pΔt)/E.", "sup.", "- (pΔt)|≧S (5) where P=the value of i when peaks appear in the envelope function and S=a set value of the comparator (115)˜1.5.", "If the equation (5) is satisfied, a possibility that the bearing is scarred increases.", "The processing in the frequency-domain operation section (14) and the frequency-domain judging section (16) are performed according to the following equations (6) and (7) by the fast Fourier converter (119).", "The original waveform is quantitized as x(iΔt) and then the following expression is operated: ##EQU2## where X(kΔf)=Fourier conversion of x(iΔt) f=divided frequency intervals of Fourier spectrum obtained k=0 to N-1 j=√-1 Following this operation, the power spectrum of P(kΔf) expressed by the following equation (7) is operated to obtain the frequency spectrum.", "P(kΔf)=X(kΔf)·X*(kΔf) (7) where P(kΔf)=the power spectrum of X(kΔf) X*(kΔf)=the conjugate complex number of X(kΔf).", "The operation of the expression (6) may easily be performed for a short time by using the algorithm of the usual fast Fourier conversion.", "The frequency spectrum obtained is investigated to determine if there is a peak in a specific frequency or not and whether a level is large or not over a wide frequency range the frequency variation detector (120).", "The result of the investigation is classified into two cases: (1) scars of the bearing, (2) the mixing of foreign substances into the lubricating oil or a shortage of oil.", "The judging section receives all the results of those operations and properly weights the result of the judgement, thereby to provide the synthetic judgement by the comparator (6).", "If the cause of the failure is the shortage of the oil or the mixing of foreign substances, a sequence of those processings are performed once and then the same sequence is repeated after a given time.", "For example, when an increase of the envelope function, more or simply an increase of the effective value of the time waveform is large, in comparison of the present effective value detected by the effective value RMS detector (109) with effective values memorized in the memory (113) before certain times, the failure is determined to be a mixing of foreign substances.", "Conversely, when it is small, the cause of the failure is a shortage of oil.", "Depending on the number of the bearings to be examined, the given time is usually 30 minutes to one hour.", "In this case, the rate of increase of the effective value when foreign substances are mixed into the lubricating oil is 7 to 10 times, compared to the effective value when the bearing is normal.", "However, in the case of oil shortage, the rate of increase is 2 to 3 times at most.", "The operations and judgement processes of the signal quantitized are executed by using a microprocessor.", "The use of the microprocessor is considered to be most suitable for these processings in the light of the cost, the use condition and the flexibility in the application of the microprocessor.", "The display section reports the result of the judgement to an operator or monitor personel while at the same time it applies the outputs to the output section.", "Each of the above noted components above discussed in connection with the disclosure of FIG. 5, as well as the other FIGUREs, are readily available in the marketplace.", "By way of examples only, memory 121 can be implemented by any available memory such as ROM or RAM manufactured by MELCO, in particular type M5L2716K, M5L 2732K, etc.", "Memory 113 can likewise be constructed using conventional memory circuits.", "Comparators 114-118 can be implemented of any of commercially available microprocessors, such as the 8085 type microprocessor.", "Fast Fourier converter 119 can be constructed using conventional Fast Fourier conversion algorithms, as for example disclosed in Cochran et al, "What is the Fast Fourier Transformer", IEEE Trans.", "on Audio and Electroacoustics, Vol. AV-15, No. 2, June, 1967, pp. 45-55.", "In the above-mentioned embodiment, a vibration is used as a signal to extract a failure, however, any other suitable medium to report a failure of the bearing may be used.", "For example, an acoustic signal may be very effective to sense the failure of the bearing.", "In this case, the sensor is a microphone." ]
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of application Ser. No. 10/174,164, filed Jun. 17, 2002, now U.S. Pat. No. 6,599,832, issued Jul. 29, 2003, which is a divisional of application Ser. No. 09/795,882, filed Feb. 28, 2001, now U.S. Pat. No. 6,410,420, issued Jun. 25, 2002, which is a continuation of application Ser. No. 09/136,384, filed Aug. 19, 1998, now U.S. Pat. No. 6,235,630, issued May 22, 2001. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to contact interfaces on the surface of semiconductor substrates and methods of forming the same. More particularly, the present invention relates to forming silicide interfaces for use with thin film devices and backend integrated circuit (“IC”) testing devices. 2. Background of Related Art In the processing of integrated circuits, electrical contact must be made to isolated active-device regions formed within a semiconductor substrate, such as a silicon wafer. Such active-device regions may include p-type and n-type source and drain regions used in the production of NMOS, PMOS, and CMOS structures for production of DRAM chips and the like. The active-device regions are connected by conductive paths or lines which are fabricated above an insulative or dielectric material covering a surface of the semiconductor substrate. To provide electrical connection between the conductive path and the active-device regions, openings in the insulative material are generally provided to enable a conductive material to contact the desired regions, thereby forming a “contact.” The openings in the insulative material are typically referred to as “contact openings.” Higher performance, lower cost, increased miniaturization of components, and greater packaging density of integrated circuits are goals of the computer industry. However, as components become smaller and smaller, tolerances for all semiconductor structures (such as circuitry traces, contacts, dielectric thickness, and the like) become more and more stringent. In fact, each new generation of semiconductor device technology has seen a reduction in contact size of, on average, about 0.7 times. Further, the reduction in size of integrated circuits also results in a reduction in the height of the integrated circuits. Of course, the reduction in contact size (i.e., diameter) has resulted in a greatly reduced area of contact between the active-device regions and the conductive material. Regardless of the conductive material used to fill these small contact openings to form the contacts (such as tungsten or aluminum), the interface between the conductive material and active-device region must have a low resistance. Various methods have been employed to reduce the contact resistance at the interface between the conductive material and active-device region. One such method includes the formation of a metal silicide contact interface atop the active-device region within the contact opening prior to the application of the conductive material into the contact opening. A common metal silicide material formed is cobalt silicide (CoSi x , wherein x is predominately equal to 2) generated from a deposited layer of cobalt. Cobalt silicide is preferred for shallow junctions of thin film structures because it forms very smooth, fine grained silicide, and will not form tightly bonded compounds with arsenic or boron atoms used in the doping of shallow junctions. FIGS. 27-31 illustrate a common method of forming a cobalt silicide layer on an active-device region of a thin film semiconductor device. FIG. 27 illustrates an intermediate structure 400 comprising a semiconductor substrate 402 with a polysilicon layer 404 thereon, wherein the polysilicon layer 404 has at least one active-device region 406 formed therein with a thin dielectric layer 408 , such as tetraethyl orthosilicate—TEOS, disposed thereover. The thin dielectric layer 408 must be as thin as possible to reduce the height of the thin film semiconductor device. A contact opening 412 is formed, by any known technique, such as patterning and etching, in the thin dielectric layer 408 to expose a portion of the active-device region 406 , as shown in FIG. 28. A thin layer of cobalt 414 is applied over the thin dielectric layer 408 and the exposed portion of the active-device region 406 , as shown in FIG. 29. A high temperature anneal step is conducted in an inert atmosphere to react the thin cobalt layer 414 with the active-device region 406 in contact therewith which forms a cobalt silicide layer 416 , as shown in FIG. 30 . However, dielectric materials, such as TEOS—tetraethyl orthosilicate, BPSG—borophosphosilicate glass, PSG—phosphosilicate glass, and BSG—borosilicate glass, and the like, are generally porous. Thus, the thin dielectric layer 408 has imperfections or voids which form passages through the thin dielectric layer 408 . Therefore, when the high-temperature anneal is conducted, cobalt silicide also forms in these passages. The cobalt silicide structures in the passages are referred to as patches 418 , as also shown in FIG. 30 . When the nonreacted cobalt layer 414 is removed to result in a final structure 422 with a cobalt silicide layer 416 formed therein, as shown in FIG. 31 , the patches 418 also form conductive paths between the upper surface of the thin dielectric layer 408 which can cause shorting and current leakage on IC backend testing devices which leads to poor repeatability and, thus, poor reliability of the data from the testing devices. Although such voids can be eliminated by forming a thicker dielectric layer 424 , the thicher dielectric layer 424 leads to poor step coverage of the cobalt material 426 in bottom corners 428 of the contact opening 412 , as shown in FIG. 32 . The poor step coverage is caused by a build-up of cobalt material 426 on the upper edges 432 of the contact opening 412 which causes shadowing of bottom corners 428 of the contact openings 412 . The result is little or no cobalt material 426 deposited at the bottom corners 428 of the contsct opening 412 and consequently an inefficient silicide contact formed after annealing. Step coverage can be improved by using filtering techniques, such as physical collimated deposition and low-pressure long throw techniques, which are used to increase the number of sputtered particles contacting the bottom of the contact opening. However, such filtering techniques are costly and the equipment is difficult to clean. Furthermore, filtering techniques also reduce the deposition rate of the cobalt material which reduces product throughput and, in turn, increases the cost of the semiconductor device. Moreover, using a thick dielectric layer is counter to the goal of reducing semiconductor device size. Finally, a thick dielectric layer eliminates the ability of the structure to be used as a backend IC probing device since the contacts are too small and too deep in the dielectric material. This is a result of dielectric material not being scalable. As device geometries get smaller, the thickness of the dielectric cannot be reduced without the potential of shorting and/or formation of patches. Thus, contact size must be increased to allow probe tips to fit in contacts, which is counter to the goal of reducing semiconductor device size. Thus, it can be appreciated that it would be advantageous to develop a technique and a contact interface which is free from patch formations, while using inexpensive, commercially available, widely practiced semiconductor device fabrication techniques and equipment without requiring complex processing steps. SUMMARY OF THE INVENTION The present invention relates to methods of forming silicide interfaces for use with thin film devices and backend integrated circuit testing devices and structures so formed. The present invention is particularly useful when a porous dielectric layer is disposed between a silicon-containing substrate and a silicidable material deposited to form a silicide contact in a desired area. As previously discussed, dielectric layers may have imperfections or voids which form passages through the thin dielectric layer. Therefore, when the high-temperature anneal is conducted to form the silicide contact from the reaction of the silicidable material and the silicon-containing substrate, a silicide material may also form in these passages through the dielectric material. Such silicide material extending through these passages can cause shorting and current leakage. The present invention prevents the formation of silicide material through passages in the dielectric material by the application of a barrier layer between the dielectric material and the silicidable material. In an exemplary method of forming a contact according to the present invention, a semiconductor substrate is provided with a polysilicon layer disposed thereon, wherein at least one active-device region is formed in a polysilicon layer. A thin dielectric layer is deposited or grown (such as by a thermal oxidation process) over the polysilicon layer and a layer of barrier material, preferably titanium nitride, is deposited over the thin dielectric layer. A mask material is patterned on the barrier material layer and a contact opening is then etched through the barrier material layer and the thin dielectric layer, preferably by an anisotropic etch, to expose a portion of the active-device region. Any remaining mask material is removed and a thin layer of silicidable material, such as cobalt, titanium, platinum, or palladium, is deposited over the barrier material layer and into the contact opening over the exposed portion of the active-device region. A high temperature anneal is conducted to react the thin silicidable material layer with the active-device region in contact therewith, which forms a silicide contact. The barrier material prevents the formation of silicide structures within voids and imperfections in the thin dielectric layer. The nonreacted silicidable material layer and remaining barrier material layer are then removed. In an exemplary method of forming a testing contact used in backend testing of semiconductor devices, a silicon-containing substrate is provided having at least one contact projection disposed thereon. A first dielectric layer is deposited or grown over the substrate and the contact projection. A layer of polysilicon is then deposited over the first dielectric layer. A second dielectric layer is optionally deposited over the polysilicon layer and a layer of barrier material is deposited over the optional second dielectric layer, or over the polysilicon, if the optional second dielectric layer is not used. A mask material is patterned on the barrier material layer. The barrier material layer and the optional second dielectric layer (if used) are then etched to expose the polysilicon layer over the contact projection, then any remaining mask material is removed. A thin layer of silicidable material is deposited over the barrier material layer and onto the exposed contact projection. A high temperature anneal is conducted to react the thin silicidable material layer with the exposed portion of the polysilicon layer over the contact projection which forms a silicide layer. The nonreacted silicidable material layer and the remaining barrier material layer are then removed to form the testing contact. BRIEF DESCRIPTION OF THE DRAWINGS While the specification concludes with claims particularly pointing out and distinctly claiming that which is regarded as the present invention, the advantages of this invention can be more readily ascertained from the following description of the invention when read in conjunction with the accompanying drawings in which: FIGS. 1-8 are cross-sectional views of a method of forming a contact interface in a thin semiconductor structure according to the present invention; FIG. 9 is a cross-sectional view of CMOS structures within a memory array of a DRAM chip formed by a method according to the present invention; FIGS. 10-17 are cross-sectional views of a method of forming a testing interface according to the present invention; FIG. 18 is a cross-sectional view of a testing interface according to the present invention with a chip-under-test disposed therein; FIGS. 19-26 are cross-sectional views of another method of forming a testing interface according to the present invention; FIGS. 27-31 are cross-sectional views of a method of forming a contact interface in a thin semiconductor structure according to a known technique; and FIG. 32 is a cross-sectional view of the deposition of a metal layer in an opening in a thick dielectric according to a known technique. DETAILED DESCRIPTION OF THE INVENTION FIGS. 1-8 illustrate a method of forming a contact interface of the present invention. It should be understood that the illustrations are not meant to be actual views of any particular semiconductor device, but are merely idealized representations which are employed to more clearly and fully depict the formation of contact interfaces in the present invention than would otherwise be possible. Additionally, elements common between FIGS. 1-8 retain the same numerical designation. Although the examples presented are directed to the formation of cobalt silicide contact interfaces, any metal or metal alloy which is capable of forming a silicide may be employed, including, but not limited to, titanium, platinum, or palladium. FIG. 1 illustrates a semiconductor substrate 100 , such as a silicon-containing substrate, having a polysilicon layer 102 thereon, wherein at least one active-device region 104 is formed in a polysilicon layer 102 , with a thin dielectric layer 106 , such as TEOS, of a thickness of approximately 1 kÅ disposed over the polysilicon layer 102 . A layer of barrier material layer 108 , preferably titanium nitride deposited to a thickness of between about 100-150 Å, is deposited over the thin dielectric layer 106 , such as by PVD, as shown in FIG. 2 . Other potential barrier materials include tungsten nitride, tungsten silicon nitride, titanium silicon nitride, and the like. A mask material 112 is patterned on the barrier material layer 108 , as shown in FIG. 3. A contact opening 114 is then etched through the barrier material layer 108 and the thin dielectric layer 106 , preferably by a dry etch such as reactive ion etching or the like, to expose a portion of the active-device region 104 , then any remaining mask material 112 is removed, as illustrated in FIG. 4. A thin layer of cobalt 116 is deposited, preferably by PVD, over the barrier material layer 108 and into the contact opening 114 over the exposed portion of the active-device region 104 , as shown in FIG. 5. A high temperature anneal step, preferably between about 400 and 800° C., most preferably between about 450 and 600° C. for between about 5 seconds and 1 hour, is conducted in an inert atmosphere, preferably nitrogen containing gas, to react the thin cobalt layer 116 with the active-device region 104 in contact therewith which forms a cobalt silicide layer 118 , as shown in FIG. 6 . The barrier material layer 108 prevents the formation of cobalt silicide structures within voids and imperfections in the thin dielectric layer 106 . In particular, it has been found that a thin titanium nitride film acts as a good diffusion barrier for a thin TEOS dielectric layer. Further, it has been found that titanium nitride does not react with cobalt. Thus, cobalt silicide patch formations have been eliminated when titanium nitride is used as a barrier layer over a thin TEOS dielectric layer. The nonreacted cobalt layer 116 is removed, preferably by a wet etch such as hydrochloric acid/peroxide or sulfuric acid/peroxide mixtures, wherein the barrier material layer 108 preferably acts as an etch stop, as shown in FIG. 7 . Preferably, the nonreacted cobalt layer 116 is etched in a dilute HPM (Hydrochloric acid/Peroxide Mixture) solution (typically, 1 volume of hydrochloric acid to 1 volume of peroxide to 5 volumes of water) for about 30 seconds at about 30° C. Such an HPM solution is preferred because its selectivity is greater than 10 4 for cobalt against cobalt silicide and titanium nitride. As shown in FIG. 8 , the remaining barrier material layer 108 is then removed, preferably by etching in an APM solution (Ammonia/Peroxide Mixture) solution (typically, 1 volume of ammonia to 1 volume of peroxide to 5 volumes of water) for between about 1 and 2 minutes at about 65° C. Such an APM solution is preferred because of its selectivity for titanium nitride against cobalt silicide and TEOS. It is contemplated that the process of the present invention may be utilized for production of DRAM chips, wherein the contact interfaces are used in the MOS structures within a memory array of a DRAM chip. Such a MOS structure 200 is illustrated in FIG. 9 as a portion of a memory array in a DRAM chip. The MOS structure 200 comprises a semiconductor substrate 202 , such as a lightly doped P-type crystal silicon substrate, which has been oxidized to form thick field oxide areas 204 and exposed to implantation processes to form drain regions 206 and source regions 208 . Transistor gate members 212 , including a wordline 214 bounded by insulative material 216 , are formed on the surface of the semiconductor substrate 202 and thick field oxide areas 204 . A barrier layer 218 is disposed over the semiconductor substrate 202 , the thick field oxide areas 204 , and the transistor gate members 212 . The barrier layer 218 has bitline contacts 222 contacting the source regions 208 for electrical communication with a bitline 224 and, further, has capacitor contacts 226 contacting the drain regions 206 for electrical communication with memory cell capacitors 228 . Each of the bitline contacts 222 and capacitor contacts 226 may have silicide layer interfaces 232 , formed as described above, for reducing resistance between the bitline contacts 222 and the source regions 208 , and between the capacitor contacts 226 and the drain regions 206 . The memory cell capacitors 228 are completed by depositing a dielectric material layer 234 , then depositing a cell poly layer 236 over the dielectric material layer 234 . FIGS. 10-17 illustrate a method of forming a testing contact used in backend testing of semiconductor devices. It should be understood that the illustrations are not meant to be actual views of any particular semiconductor device, but are merely idealized representations which are employed to more clearly and fully depict the formation of contact interfaces in the present invention than would otherwise be possible. Additionally, elements common between FIGS. 10-17 retain the same numerical designation. FIG. 10 illustrates a substrate 302 having at least one contact projection 304 disposed thereon, preferably with a height of approximately 100 μm, wherein the substrate 302 and the contact projection 304 have a first dielectric layer 306 , preferably silicon dioxide, disposed thereover. The first dielectric layer 306 may be deposited by any known technique or, if silicon dioxide, may be grown on the surface of the substrate 302 by a thermal oxidation process. A layer of polysilicon 308 is deposited by any known technique over the first dielectric layer 306 . As shown in FIG. 11 , a second dielectric layer 312 , such as TEOS or silicon dioxide, is deposited over the polysilicon layer 308 and a layer of barrier material 314 , preferably titanium nitride, is deposited over the second dielectric layer 312 , such as by PVD. A mask material 316 is patterned on the barrier material layer 314 , as shown in FIG. 12 . The barrier material layer 314 and the second dielectric layer 312 are then etched, preferably by a dry etch such as reactive ion etching or plasma etching, to expose the polysilicon layer 308 over the contact projection 304 , then any remaining mask material 316 is removed, as illustrated in FIG. 13. A thin layer of cobalt 318 is deposited, preferably by PVD, over the barrier material layer 314 and onto the exposed contact projection 304 , as shown in FIG. 14. A high temperature anneal step, preferably between about 400 and 800° C., most preferably between about 450 and 600° C. for between about 5 seconds and 1 hour, is conducted in an inert atmosphere, preferably nitrogen containing gas, to react the thin cobalt layer 318 with the exposed portion of the polysilicon layer 308 over the contact projection 304 which forms a cobalt silicide layer 322 , as shown in FIG. 15 . The nonreacted cobalt layer 318 is removed, preferably by a wet etch, such as hydrochloric acid/peroxide or sulfuric acid/peroxide mixtures, wherein the barrier material layer 314 preferably acts as an etch stop, as shown in FIG. 16 . Preferably, the nonreacted cobalt layer 318 is etched in a dilute HPM (Hydrochloric acid/Peroxide Mixture) solution (typically, 1 volume of hydrochloric acid to 1 volume of peroxide to 5 volumes of water) for about 30 seconds at about 30° C. As shown in FIG. 17 , the remaining barrier material layer 314 is then removed, preferably etching in an APM (Ammonia/Peroxide Mixture) solution (typically, 1 volume of ammonia to 1 volume of peroxide to 5 volumes of water) for between about 1 and 2 minutes at about 65° C., and the remaining second dielectric layer 312 and polysilicon layer 308 are also removed, by any known technique. The cobalt silicide layer 322 is not disturbed by the removal of the remaining barrier material layer 314 or the removal of the second dielectric layer 312 and polysilicon layer 308 , as dry etches containing chlorine or fluorine will not etch cobalt silicide (i.e., CoF x and CoCl x are nonvolatile). Structures such as illustrated in FIG. 17 are generally used for testing of flip-chips, wherein, as illustrated in FIG. 18 , solder bumps 332 of a flip-chip 330 electrically contact the cobalt silicide layer 322 . The cobalt silicide layer 322 conducts electrical signals to and/or receives electrical signals from the flip-chip 330 through the solder bumps 332 . FIGS. 19-26 illustrate another method of forming a testing contact used in backend testing of semiconductor devices. Elements common between FIGS. 10-17 and FIGS. 19-26 retain the same numerical designation. FIG. 19 illustrates a substrate 302 having at least one contact projection 304 disposed thereon, wherein the substrate 302 and the contact projection 304 have a first dielectric layer 306 , preferably silicon dioxide, disposed thereover. A layer of polysilicon 308 is deposited by any known technique over the first dielectric layer 306 . As shown in FIG. 20 , a layer of barrier material 314 , preferably titanium nitride, is deposited over the polysilicon layer 308 . A mask material 316 is patterned on the barrier material layer 314 , as shown in FIG. 21 . The barrier material layer 314 is then etched to expose the polysilicon layer 308 over the contact projection 304 , then any remaining mask material 316 is removed, as illustrated in FIG. 22. A thin layer of cobalt 318 is deposited over the barrier material layer 314 and onto the exposed contact projection 304 , as shown in FIG. 23. A high temperature anneal step, preferably between about 400 and 800° C., most preferably between about 450 and 600° C. for between about 5 seconds and 1 hour, is conducted in an inert atmosphere, preferably nitrogen containing gas, to react the thin cobalt layer 318 with the exposed portion of the polysilicon layer 308 over the contact projection 304 which forms a cobalt silicide layer 322 , as shown in FIG. 24 . The nonreacted cobalt layer 318 is removed, preferably by a wet etch, such as hydrochloric acid/peroxide or sulfuric acid/peroxide mixtures, wherein the barrier material layer 314 preferably acts as an etch stop, as shown in FIG. 25 . As shown in FIG. 26 , the remaining barrier material layer 314 and the remaining polysilicon layer 308 are removed. Having thus described in detail preferred embodiments of the present invention, it is to be understood that the invention defined by the appended claims is not to be limited by particular details set forth in the above description as many apparent variations thereof are possible without departing from the spirit or scope thereof.
Silicide interfaces for integrated circuits, thin film devices, and back-end integrated circuit testing devices are formed using a barrier layer, such as titanium nitride, disposed over a porous, thin dielectric layer which is disposed between a silicon-containing substrate and a silicidable material which is deposited to form the silicide interfaces for such devices. The barrier layer prevents the formation of a silicide material within imperfections or voids which form passages through the thin dielectric layer when the device is subjected to a high-temperature anneal to form the silicide contact from the reaction of the silicidable material and the silicon-containing substrate.
Identify and summarize the most critical features from the given passage.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of application Ser.", "No. 10/174,164, filed Jun. 17, 2002, now U.S. Pat. No. 6,599,832, issued Jul. 29, 2003, which is a divisional of application Ser.", "No. 09/795,882, filed Feb. 28, 2001, now U.S. Pat. No. 6,410,420, issued Jun. 25, 2002, which is a continuation of application Ser.", "No. 09/136,384, filed Aug. 19, 1998, now U.S. Pat. No. 6,235,630, issued May 22, 2001.", "BACKGROUND OF THE INVENTION 1.", "Field of the Invention The present invention relates to contact interfaces on the surface of semiconductor substrates and methods of forming the same.", "More particularly, the present invention relates to forming silicide interfaces for use with thin film devices and backend integrated circuit (“IC”) testing devices.", "Background of Related Art In the processing of integrated circuits, electrical contact must be made to isolated active-device regions formed within a semiconductor substrate, such as a silicon wafer.", "Such active-device regions may include p-type and n-type source and drain regions used in the production of NMOS, PMOS, and CMOS structures for production of DRAM chips and the like.", "The active-device regions are connected by conductive paths or lines which are fabricated above an insulative or dielectric material covering a surface of the semiconductor substrate.", "To provide electrical connection between the conductive path and the active-device regions, openings in the insulative material are generally provided to enable a conductive material to contact the desired regions, thereby forming a “contact.”", "The openings in the insulative material are typically referred to as “contact openings.”", "Higher performance, lower cost, increased miniaturization of components, and greater packaging density of integrated circuits are goals of the computer industry.", "However, as components become smaller and smaller, tolerances for all semiconductor structures (such as circuitry traces, contacts, dielectric thickness, and the like) become more and more stringent.", "In fact, each new generation of semiconductor device technology has seen a reduction in contact size of, on average, about 0.7 times.", "Further, the reduction in size of integrated circuits also results in a reduction in the height of the integrated circuits.", "Of course, the reduction in contact size (i.e., diameter) has resulted in a greatly reduced area of contact between the active-device regions and the conductive material.", "Regardless of the conductive material used to fill these small contact openings to form the contacts (such as tungsten or aluminum), the interface between the conductive material and active-device region must have a low resistance.", "Various methods have been employed to reduce the contact resistance at the interface between the conductive material and active-device region.", "One such method includes the formation of a metal silicide contact interface atop the active-device region within the contact opening prior to the application of the conductive material into the contact opening.", "A common metal silicide material formed is cobalt silicide (CoSi x , wherein x is predominately equal to 2) generated from a deposited layer of cobalt.", "Cobalt silicide is preferred for shallow junctions of thin film structures because it forms very smooth, fine grained silicide, and will not form tightly bonded compounds with arsenic or boron atoms used in the doping of shallow junctions.", "FIGS. 27-31 illustrate a common method of forming a cobalt silicide layer on an active-device region of a thin film semiconductor device.", "FIG. 27 illustrates an intermediate structure 400 comprising a semiconductor substrate 402 with a polysilicon layer 404 thereon, wherein the polysilicon layer 404 has at least one active-device region 406 formed therein with a thin dielectric layer 408 , such as tetraethyl orthosilicate—TEOS, disposed thereover.", "The thin dielectric layer 408 must be as thin as possible to reduce the height of the thin film semiconductor device.", "A contact opening 412 is formed, by any known technique, such as patterning and etching, in the thin dielectric layer 408 to expose a portion of the active-device region 406 , as shown in FIG. 28.", "A thin layer of cobalt 414 is applied over the thin dielectric layer 408 and the exposed portion of the active-device region 406 , as shown in FIG. 29.", "A high temperature anneal step is conducted in an inert atmosphere to react the thin cobalt layer 414 with the active-device region 406 in contact therewith which forms a cobalt silicide layer 416 , as shown in FIG. 30 .", "However, dielectric materials, such as TEOS—tetraethyl orthosilicate, BPSG—borophosphosilicate glass, PSG—phosphosilicate glass, and BSG—borosilicate glass, and the like, are generally porous.", "Thus, the thin dielectric layer 408 has imperfections or voids which form passages through the thin dielectric layer 408 .", "Therefore, when the high-temperature anneal is conducted, cobalt silicide also forms in these passages.", "The cobalt silicide structures in the passages are referred to as patches 418 , as also shown in FIG. 30 .", "When the nonreacted cobalt layer 414 is removed to result in a final structure 422 with a cobalt silicide layer 416 formed therein, as shown in FIG. 31 , the patches 418 also form conductive paths between the upper surface of the thin dielectric layer 408 which can cause shorting and current leakage on IC backend testing devices which leads to poor repeatability and, thus, poor reliability of the data from the testing devices.", "Although such voids can be eliminated by forming a thicker dielectric layer 424 , the thicher dielectric layer 424 leads to poor step coverage of the cobalt material 426 in bottom corners 428 of the contact opening 412 , as shown in FIG. 32 .", "The poor step coverage is caused by a build-up of cobalt material 426 on the upper edges 432 of the contact opening 412 which causes shadowing of bottom corners 428 of the contact openings 412 .", "The result is little or no cobalt material 426 deposited at the bottom corners 428 of the contsct opening 412 and consequently an inefficient silicide contact formed after annealing.", "Step coverage can be improved by using filtering techniques, such as physical collimated deposition and low-pressure long throw techniques, which are used to increase the number of sputtered particles contacting the bottom of the contact opening.", "However, such filtering techniques are costly and the equipment is difficult to clean.", "Furthermore, filtering techniques also reduce the deposition rate of the cobalt material which reduces product throughput and, in turn, increases the cost of the semiconductor device.", "Moreover, using a thick dielectric layer is counter to the goal of reducing semiconductor device size.", "Finally, a thick dielectric layer eliminates the ability of the structure to be used as a backend IC probing device since the contacts are too small and too deep in the dielectric material.", "This is a result of dielectric material not being scalable.", "As device geometries get smaller, the thickness of the dielectric cannot be reduced without the potential of shorting and/or formation of patches.", "Thus, contact size must be increased to allow probe tips to fit in contacts, which is counter to the goal of reducing semiconductor device size.", "Thus, it can be appreciated that it would be advantageous to develop a technique and a contact interface which is free from patch formations, while using inexpensive, commercially available, widely practiced semiconductor device fabrication techniques and equipment without requiring complex processing steps.", "SUMMARY OF THE INVENTION The present invention relates to methods of forming silicide interfaces for use with thin film devices and backend integrated circuit testing devices and structures so formed.", "The present invention is particularly useful when a porous dielectric layer is disposed between a silicon-containing substrate and a silicidable material deposited to form a silicide contact in a desired area.", "As previously discussed, dielectric layers may have imperfections or voids which form passages through the thin dielectric layer.", "Therefore, when the high-temperature anneal is conducted to form the silicide contact from the reaction of the silicidable material and the silicon-containing substrate, a silicide material may also form in these passages through the dielectric material.", "Such silicide material extending through these passages can cause shorting and current leakage.", "The present invention prevents the formation of silicide material through passages in the dielectric material by the application of a barrier layer between the dielectric material and the silicidable material.", "In an exemplary method of forming a contact according to the present invention, a semiconductor substrate is provided with a polysilicon layer disposed thereon, wherein at least one active-device region is formed in a polysilicon layer.", "A thin dielectric layer is deposited or grown (such as by a thermal oxidation process) over the polysilicon layer and a layer of barrier material, preferably titanium nitride, is deposited over the thin dielectric layer.", "A mask material is patterned on the barrier material layer and a contact opening is then etched through the barrier material layer and the thin dielectric layer, preferably by an anisotropic etch, to expose a portion of the active-device region.", "Any remaining mask material is removed and a thin layer of silicidable material, such as cobalt, titanium, platinum, or palladium, is deposited over the barrier material layer and into the contact opening over the exposed portion of the active-device region.", "A high temperature anneal is conducted to react the thin silicidable material layer with the active-device region in contact therewith, which forms a silicide contact.", "The barrier material prevents the formation of silicide structures within voids and imperfections in the thin dielectric layer.", "The nonreacted silicidable material layer and remaining barrier material layer are then removed.", "In an exemplary method of forming a testing contact used in backend testing of semiconductor devices, a silicon-containing substrate is provided having at least one contact projection disposed thereon.", "A first dielectric layer is deposited or grown over the substrate and the contact projection.", "A layer of polysilicon is then deposited over the first dielectric layer.", "A second dielectric layer is optionally deposited over the polysilicon layer and a layer of barrier material is deposited over the optional second dielectric layer, or over the polysilicon, if the optional second dielectric layer is not used.", "A mask material is patterned on the barrier material layer.", "The barrier material layer and the optional second dielectric layer (if used) are then etched to expose the polysilicon layer over the contact projection, then any remaining mask material is removed.", "A thin layer of silicidable material is deposited over the barrier material layer and onto the exposed contact projection.", "A high temperature anneal is conducted to react the thin silicidable material layer with the exposed portion of the polysilicon layer over the contact projection which forms a silicide layer.", "The nonreacted silicidable material layer and the remaining barrier material layer are then removed to form the testing contact.", "BRIEF DESCRIPTION OF THE DRAWINGS While the specification concludes with claims particularly pointing out and distinctly claiming that which is regarded as the present invention, the advantages of this invention can be more readily ascertained from the following description of the invention when read in conjunction with the accompanying drawings in which: FIGS. 1-8 are cross-sectional views of a method of forming a contact interface in a thin semiconductor structure according to the present invention;", "FIG. 9 is a cross-sectional view of CMOS structures within a memory array of a DRAM chip formed by a method according to the present invention;", "FIGS. 10-17 are cross-sectional views of a method of forming a testing interface according to the present invention;", "FIG. 18 is a cross-sectional view of a testing interface according to the present invention with a chip-under-test disposed therein;", "FIGS. 19-26 are cross-sectional views of another method of forming a testing interface according to the present invention;", "FIGS. 27-31 are cross-sectional views of a method of forming a contact interface in a thin semiconductor structure according to a known technique;", "and FIG. 32 is a cross-sectional view of the deposition of a metal layer in an opening in a thick dielectric according to a known technique.", "DETAILED DESCRIPTION OF THE INVENTION FIGS. 1-8 illustrate a method of forming a contact interface of the present invention.", "It should be understood that the illustrations are not meant to be actual views of any particular semiconductor device, but are merely idealized representations which are employed to more clearly and fully depict the formation of contact interfaces in the present invention than would otherwise be possible.", "Additionally, elements common between FIGS. 1-8 retain the same numerical designation.", "Although the examples presented are directed to the formation of cobalt silicide contact interfaces, any metal or metal alloy which is capable of forming a silicide may be employed, including, but not limited to, titanium, platinum, or palladium.", "FIG. 1 illustrates a semiconductor substrate 100 , such as a silicon-containing substrate, having a polysilicon layer 102 thereon, wherein at least one active-device region 104 is formed in a polysilicon layer 102 , with a thin dielectric layer 106 , such as TEOS, of a thickness of approximately 1 kÅ disposed over the polysilicon layer 102 .", "A layer of barrier material layer 108 , preferably titanium nitride deposited to a thickness of between about 100-150 Å, is deposited over the thin dielectric layer 106 , such as by PVD, as shown in FIG. 2 .", "Other potential barrier materials include tungsten nitride, tungsten silicon nitride, titanium silicon nitride, and the like.", "A mask material 112 is patterned on the barrier material layer 108 , as shown in FIG. 3. A contact opening 114 is then etched through the barrier material layer 108 and the thin dielectric layer 106 , preferably by a dry etch such as reactive ion etching or the like, to expose a portion of the active-device region 104 , then any remaining mask material 112 is removed, as illustrated in FIG. 4. A thin layer of cobalt 116 is deposited, preferably by PVD, over the barrier material layer 108 and into the contact opening 114 over the exposed portion of the active-device region 104 , as shown in FIG. 5. A high temperature anneal step, preferably between about 400 and 800° C., most preferably between about 450 and 600° C. for between about 5 seconds and 1 hour, is conducted in an inert atmosphere, preferably nitrogen containing gas, to react the thin cobalt layer 116 with the active-device region 104 in contact therewith which forms a cobalt silicide layer 118 , as shown in FIG. 6 .", "The barrier material layer 108 prevents the formation of cobalt silicide structures within voids and imperfections in the thin dielectric layer 106 .", "In particular, it has been found that a thin titanium nitride film acts as a good diffusion barrier for a thin TEOS dielectric layer.", "Further, it has been found that titanium nitride does not react with cobalt.", "Thus, cobalt silicide patch formations have been eliminated when titanium nitride is used as a barrier layer over a thin TEOS dielectric layer.", "The nonreacted cobalt layer 116 is removed, preferably by a wet etch such as hydrochloric acid/peroxide or sulfuric acid/peroxide mixtures, wherein the barrier material layer 108 preferably acts as an etch stop, as shown in FIG. 7 .", "Preferably, the nonreacted cobalt layer 116 is etched in a dilute HPM (Hydrochloric acid/Peroxide Mixture) solution (typically, 1 volume of hydrochloric acid to 1 volume of peroxide to 5 volumes of water) for about 30 seconds at about 30° C. Such an HPM solution is preferred because its selectivity is greater than 10 4 for cobalt against cobalt silicide and titanium nitride.", "As shown in FIG. 8 , the remaining barrier material layer 108 is then removed, preferably by etching in an APM solution (Ammonia/Peroxide Mixture) solution (typically, 1 volume of ammonia to 1 volume of peroxide to 5 volumes of water) for between about 1 and 2 minutes at about 65° C. Such an APM solution is preferred because of its selectivity for titanium nitride against cobalt silicide and TEOS.", "It is contemplated that the process of the present invention may be utilized for production of DRAM chips, wherein the contact interfaces are used in the MOS structures within a memory array of a DRAM chip.", "Such a MOS structure 200 is illustrated in FIG. 9 as a portion of a memory array in a DRAM chip.", "The MOS structure 200 comprises a semiconductor substrate 202 , such as a lightly doped P-type crystal silicon substrate, which has been oxidized to form thick field oxide areas 204 and exposed to implantation processes to form drain regions 206 and source regions 208 .", "Transistor gate members 212 , including a wordline 214 bounded by insulative material 216 , are formed on the surface of the semiconductor substrate 202 and thick field oxide areas 204 .", "A barrier layer 218 is disposed over the semiconductor substrate 202 , the thick field oxide areas 204 , and the transistor gate members 212 .", "The barrier layer 218 has bitline contacts 222 contacting the source regions 208 for electrical communication with a bitline 224 and, further, has capacitor contacts 226 contacting the drain regions 206 for electrical communication with memory cell capacitors 228 .", "Each of the bitline contacts 222 and capacitor contacts 226 may have silicide layer interfaces 232 , formed as described above, for reducing resistance between the bitline contacts 222 and the source regions 208 , and between the capacitor contacts 226 and the drain regions 206 .", "The memory cell capacitors 228 are completed by depositing a dielectric material layer 234 , then depositing a cell poly layer 236 over the dielectric material layer 234 .", "FIGS. 10-17 illustrate a method of forming a testing contact used in backend testing of semiconductor devices.", "It should be understood that the illustrations are not meant to be actual views of any particular semiconductor device, but are merely idealized representations which are employed to more clearly and fully depict the formation of contact interfaces in the present invention than would otherwise be possible.", "Additionally, elements common between FIGS. 10-17 retain the same numerical designation.", "FIG. 10 illustrates a substrate 302 having at least one contact projection 304 disposed thereon, preferably with a height of approximately 100 μm, wherein the substrate 302 and the contact projection 304 have a first dielectric layer 306 , preferably silicon dioxide, disposed thereover.", "The first dielectric layer 306 may be deposited by any known technique or, if silicon dioxide, may be grown on the surface of the substrate 302 by a thermal oxidation process.", "A layer of polysilicon 308 is deposited by any known technique over the first dielectric layer 306 .", "As shown in FIG. 11 , a second dielectric layer 312 , such as TEOS or silicon dioxide, is deposited over the polysilicon layer 308 and a layer of barrier material 314 , preferably titanium nitride, is deposited over the second dielectric layer 312 , such as by PVD.", "A mask material 316 is patterned on the barrier material layer 314 , as shown in FIG. 12 .", "The barrier material layer 314 and the second dielectric layer 312 are then etched, preferably by a dry etch such as reactive ion etching or plasma etching, to expose the polysilicon layer 308 over the contact projection 304 , then any remaining mask material 316 is removed, as illustrated in FIG. 13.", "A thin layer of cobalt 318 is deposited, preferably by PVD, over the barrier material layer 314 and onto the exposed contact projection 304 , as shown in FIG. 14.", "A high temperature anneal step, preferably between about 400 and 800° C., most preferably between about 450 and 600° C. for between about 5 seconds and 1 hour, is conducted in an inert atmosphere, preferably nitrogen containing gas, to react the thin cobalt layer 318 with the exposed portion of the polysilicon layer 308 over the contact projection 304 which forms a cobalt silicide layer 322 , as shown in FIG. 15 .", "The nonreacted cobalt layer 318 is removed, preferably by a wet etch, such as hydrochloric acid/peroxide or sulfuric acid/peroxide mixtures, wherein the barrier material layer 314 preferably acts as an etch stop, as shown in FIG. 16 .", "Preferably, the nonreacted cobalt layer 318 is etched in a dilute HPM (Hydrochloric acid/Peroxide Mixture) solution (typically, 1 volume of hydrochloric acid to 1 volume of peroxide to 5 volumes of water) for about 30 seconds at about 30° C. As shown in FIG. 17 , the remaining barrier material layer 314 is then removed, preferably etching in an APM (Ammonia/Peroxide Mixture) solution (typically, 1 volume of ammonia to 1 volume of peroxide to 5 volumes of water) for between about 1 and 2 minutes at about 65° C., and the remaining second dielectric layer 312 and polysilicon layer 308 are also removed, by any known technique.", "The cobalt silicide layer 322 is not disturbed by the removal of the remaining barrier material layer 314 or the removal of the second dielectric layer 312 and polysilicon layer 308 , as dry etches containing chlorine or fluorine will not etch cobalt silicide (i.e., CoF x and CoCl x are nonvolatile).", "Structures such as illustrated in FIG. 17 are generally used for testing of flip-chips, wherein, as illustrated in FIG. 18 , solder bumps 332 of a flip-chip 330 electrically contact the cobalt silicide layer 322 .", "The cobalt silicide layer 322 conducts electrical signals to and/or receives electrical signals from the flip-chip 330 through the solder bumps 332 .", "FIGS. 19-26 illustrate another method of forming a testing contact used in backend testing of semiconductor devices.", "Elements common between FIGS. 10-17 and FIGS. 19-26 retain the same numerical designation.", "FIG. 19 illustrates a substrate 302 having at least one contact projection 304 disposed thereon, wherein the substrate 302 and the contact projection 304 have a first dielectric layer 306 , preferably silicon dioxide, disposed thereover.", "A layer of polysilicon 308 is deposited by any known technique over the first dielectric layer 306 .", "As shown in FIG. 20 , a layer of barrier material 314 , preferably titanium nitride, is deposited over the polysilicon layer 308 .", "A mask material 316 is patterned on the barrier material layer 314 , as shown in FIG. 21 .", "The barrier material layer 314 is then etched to expose the polysilicon layer 308 over the contact projection 304 , then any remaining mask material 316 is removed, as illustrated in FIG. 22.", "A thin layer of cobalt 318 is deposited over the barrier material layer 314 and onto the exposed contact projection 304 , as shown in FIG. 23.", "A high temperature anneal step, preferably between about 400 and 800° C., most preferably between about 450 and 600° C. for between about 5 seconds and 1 hour, is conducted in an inert atmosphere, preferably nitrogen containing gas, to react the thin cobalt layer 318 with the exposed portion of the polysilicon layer 308 over the contact projection 304 which forms a cobalt silicide layer 322 , as shown in FIG. 24 .", "The nonreacted cobalt layer 318 is removed, preferably by a wet etch, such as hydrochloric acid/peroxide or sulfuric acid/peroxide mixtures, wherein the barrier material layer 314 preferably acts as an etch stop, as shown in FIG. 25 .", "As shown in FIG. 26 , the remaining barrier material layer 314 and the remaining polysilicon layer 308 are removed.", "Having thus described in detail preferred embodiments of the present invention, it is to be understood that the invention defined by the appended claims is not to be limited by particular details set forth in the above description as many apparent variations thereof are possible without departing from the spirit or scope thereof." ]
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to devices used in the assay of a liquid sample. The device of this invention is suitable for use as a clinical diagnostic device in the measurement of the component of blood and urine and other substances. 2. Description of the Related Art Known conventional devices used to assay of liquid sample are (1) assay devices for which filter paper is cut to a specified size, and is made to absorb the reagent that is to react with the sample, then the filter paper is attached to a support, and (2) assay devices for which gelatin containing the reagent is formed into a specified shape, then attached to a support. After preparing the assay device, the liquid samples are required to drop on the filter paper or the gelatin for assay. The above-noted assay devices, however, require that the manufacturing process include the cutting and attaching of filter paper or gelatin. This does not allow refinement of the assay elements that hold the reagent, which, in turn, does not allow the miniaturization of the assay device as a whole, compared with its current form. Moreover, to enable the assay of a multiplicity of items using a single assay device, the above-noted conventional assay devices require the cutting and attaching of a multiplicity of filter paper or gelatins, thereby increasing the number of steps in the manufacturing process and increasing the manufacturing costs. SUMMARY OF THE INVENTION Therefore, the first object of this invention is to provide an assay device in which the assay elements that hold the sample have been refined. The second object of this invention is to provide an assay device manufactured with a multiplicity of assay elements, using few steps. The third object of this invention is to provide an assay device in which the detector and the part on which the sample is applied are separated from each other. To achieve the objects described above, the liquid assay device of this invention comprises: a support composed of an organic macromolecule, said support having a surface divided into two areas located adjacent to each other; a divider in the surface, defining the border of both areas to separate a first area from a second area; a detection layer affixed to the first area and containing a reagent; and a water-swelling layer affixed to the second area, said water-swelling layer expanding by absorbing water. To assay liquid samples using this device, a drop of the liquid sample is applied to the water-swelling layer. When the drop is applied, the water-swelling layer expands, extending over the divider and coming into contact with the detection layer. The liquid sample then moves by capillarity from the water-swelling layer to the detection layer, where it reacts with the reagent. If the reagent is such that it produces color or emits light when reacting to specific components, the components contained within the sample can be identified using optical methods. Depending on the properties of the reagent, other methods may also be used to identify components in the sample. The detection layer of the device of this invention is separated from the location (the water-swelling layer) where the sample is dropped to, so when the sample is flowing from the water-swelling layer to the detection layer, a specific component within the sample can be removed from the sample. An example would be separating out the corpuscles when blood is being assayed. Moreover, a second reagent, that differs from the reagent contained in the detection layer, can be put in the water-swelling layer. When the divider is composed of a water-repellent material, the reagent contained in the detection layer will not flow over onto the water-swelling layer until the reagent reacts with the sample, even if said reagent is a liquid. A suitable method for manufacturing the device of this invention comprises the following steps: (a) reforming the perimeter of a specific area on a surface of a support composed of an organic macromolecule so as to render it hydrophilic; (b) forming a divider composed of a water-repellent material on the reformed perimeter; (c) reforming the specific area and other area adjacent to the divider so as to render them hydrophilic; (d) affixing a detection layer and a water-swelling layer to the reformed specific area and another reformed area respectively, said detection layer containing reagent, said water-swelling layer expanding by absorbing water. This invention enables the refinement of the detection layer, by using the hydrophilic properties of the support to make a detection layer, a divider, and a water-swelling layer. Moreover, manufacturing costs are low, because there is no cutting and attaching work in the manufacturing process and a multiplicity of detection layers can be affixed simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A, 1B, 1C, 1D and 1E are perspective views that show the manufacturing process of an actual embodiment of the assay device. FIG. 2 is a sectional view of the assay device, taken along line II--II of FIG. 1E. FIG. 3 is a sectional view of the assay device in a operating condition, taken along line II--II of FIG. 1E. DESCRIPTION OF THE PREFERRED EMBODIMENTS An actual embodiment of this invention will be explained along with drawings. FIG. 1 shows the processing order used to manufacture the device of this invention. First, the organic macromolecule materials that are to comprise the support and the shape of the support are chosen. One or more of the following substances can be used as the organic macromolecule molecule: polyethylene, polypropylene, polystyrene, ABS, poly(vinyl chloride), poly(vinylidene chloride), thermoplastic polyurethane, poly(methyl methacrylate), polyoxyethylene, polycarbonate, polyamide, acetal resin, poly(phenyleneoxide), poly(butyleneterephthalate), poly(ethylene terephthalate), poly(phenylene sulfide), or other thermoplastic resins; unsaturated polyester resin, epoxy resin, phenol resin, urea resin, melamine resin, diallyl phthalate resin, or other thermosetting resins; styrene-butadiene rubber, polyisoprene rubber, natural rubber, or other rubbers. The shape of the support can be of sheet form, column form, cylinder form, membrane form, or any form that provides the areas on which to affix the detection layer and water-swelling layer. As shown in drawing FIG. 1A, the first areas 1a, where the detection layer is to be affixed, and the second area (to be explained below), where the water-swelling layer is to be affixed, are specified on the surface of the support 1, which is composed of organic macromolecule. In this example, the first areas are round in shape and the second area is a rectangle surrounding the first areas. The perimeters 1b of the respective first areas 1a are reformed so as to render them hydrophilic. The following methods can be used to reform parts of the support so as to render them hydrophilic: chemical processing which masks the surface of hydrophobic organic macromolecule, then chemically introduces hydrophilic groups or graft branches into exposed areas (where the mask does not cover the organic macromolecule) to render only the exposed areas hydrophilic; or plasma processing; corona discharge processing; UV irradiation; or other processing. Of these methods, irradiation with UV rays works well, because it requires no special pre- or post-processing and the necessary equipment is simple. A low-pressure mercury lamp is an ideal optimal source for the UV rays, because it has a low tube-wall temperature of approximately 100° C. and radiates high-energy, short wavelength UV rays. Short wavelength UV rays of 185 nm are good, because they have high energy, with the next best wave length being 254 nm. Irradiation should normally take place for a time period of from 1 to 120 minutes, at an irradiation distance of between 0.5 and 8 cm, and an illumination intensity of from 1 to 20 mW/cm 2 . Next, as shown in drawing FIG. 1B, dividers 2 composed of water-repellent material are formed on the reformed perimeters 1b. Good substance to use as the water-repellent material is a resin containing a function group that is bondable with carboxyl group or hydroxyl group, or a surface active agent. This is because molecules existing on the surface of the organic macromolecule prior to reforming, even carbon or hydrogen, are often substituted by the reforming into carboxyl or hydroxyl group. So, if the water-repellent material is a resin containing a function group that bonds chemically or physically with these molecules or if it is a surface active agent, it bonds with the reformed perimeter areas 1b and easily forms the dividers 2. Many kinds of this type of water-repellent material are known, such as silane coupling agent, fluorine compounded acrylic copolymer emulsion, amino-group denatured silicon oil, silane coupling agent--fluoroalkyl silicon chloride mixture, polyoxyalkylene denatured silicon oil, fluorine-based surface active agent, or fluorine silicon surface active agent. Following the formation of dividers 2, as shown in drawing FIG. 1C, the first areas 1a, which are surrounded by the dividers 2, and the rectangular second area 1c, which encloses the dividers 2, are reformed so as to render them hydrophilic. If UV irradiation is used to conduct the reforming, as noted above, a fluorine based or silicon based substance is good as the water-repellent material that composes the divider 2. This is because fluorine-based and silicon-based substances are inactive when exposed to UV light, so the function of the dividers 2 is not diminished by UV rays. The areas 1a and 1c may be reformed simultaneously, or separately with using a mask to block the UV rays. Even when the reforming is carried out separately for each area, if a fluorine or silicon based substance is used as the water-repellent material, the precision of the mask pattern is not required so strictly. Finally, a liquid made by solving the reagent is applied to the first areas 1a (drawing FIG. 1D) and gel composed of water-swelling material is applied to the second area 1c (drawing FIG. 1E). The water-swelling material can be, for example, water-absorptive resin, clay, or other inorganic compound in layer form. The liquid applied to the first areas 1a dries to become the detection layer 3. The gel applied to the second area 1c dries to become the water-swelling layer 4. The areas 1a and 1c can have their respective liquids applied simultaneously or one at a time. A perspective view diagram of the assay device obtained via the above-noted processes is shown in FIG. 1E. FIG. 2 is a sectional view taken on the line II--II of FIG. 1E. When this device is used to conduct an assay, drops of the liquid sample are applied onto the water-swelling layer 4. When the drops are applied, the water-swelling layer expands, extending over the dividers 2 and coming into contact with the detection layers 3. The liquid sample then moves by capillarity from the water-swelling layer 4 to the detection layer 3, where it reacts with the reagent. FIG. 3 shows the water-swelling layer 4 swelling and the detection layer 3 reacting with the liquid sample. To enable the assay of a multiplicity of items using a single assay device, a multiplicity of detection layers 3 may be made on a single support 1, each surrounded individually within a multiplicity of closed dividers 2 on the support 1. The drawings show a device made with the objective of simultaneously assaying two items. This enables the liquid sample to simultaneously flow from the water-swelling layer 4 into a multiplicity of detection layers 3, where it reacts separately with each of the reagent.
A device for assay of a liquid sample. The device comprises: a support composed of an organic macromolecule, the support having a surface divided into two areas located adjacent to each other; a divider in the surface, defining the border of both areas to separate a first area from a second area; a detection layer affixed to the first area and containing a reagent; and a water-swelling layer affixed to the second area, the water-swelling layer expanding by absorbing water.
Identify the most important aspect in the document and summarize the concept accordingly.
[ "BACKGROUND OF THE INVENTION 1.", "Field of the Invention This invention relates to devices used in the assay of a liquid sample.", "The device of this invention is suitable for use as a clinical diagnostic device in the measurement of the component of blood and urine and other substances.", "Description of the Related Art Known conventional devices used to assay of liquid sample are (1) assay devices for which filter paper is cut to a specified size, and is made to absorb the reagent that is to react with the sample, then the filter paper is attached to a support, and (2) assay devices for which gelatin containing the reagent is formed into a specified shape, then attached to a support.", "After preparing the assay device, the liquid samples are required to drop on the filter paper or the gelatin for assay.", "The above-noted assay devices, however, require that the manufacturing process include the cutting and attaching of filter paper or gelatin.", "This does not allow refinement of the assay elements that hold the reagent, which, in turn, does not allow the miniaturization of the assay device as a whole, compared with its current form.", "Moreover, to enable the assay of a multiplicity of items using a single assay device, the above-noted conventional assay devices require the cutting and attaching of a multiplicity of filter paper or gelatins, thereby increasing the number of steps in the manufacturing process and increasing the manufacturing costs.", "SUMMARY OF THE INVENTION Therefore, the first object of this invention is to provide an assay device in which the assay elements that hold the sample have been refined.", "The second object of this invention is to provide an assay device manufactured with a multiplicity of assay elements, using few steps.", "The third object of this invention is to provide an assay device in which the detector and the part on which the sample is applied are separated from each other.", "To achieve the objects described above, the liquid assay device of this invention comprises: a support composed of an organic macromolecule, said support having a surface divided into two areas located adjacent to each other;", "a divider in the surface, defining the border of both areas to separate a first area from a second area;", "a detection layer affixed to the first area and containing a reagent;", "and a water-swelling layer affixed to the second area, said water-swelling layer expanding by absorbing water.", "To assay liquid samples using this device, a drop of the liquid sample is applied to the water-swelling layer.", "When the drop is applied, the water-swelling layer expands, extending over the divider and coming into contact with the detection layer.", "The liquid sample then moves by capillarity from the water-swelling layer to the detection layer, where it reacts with the reagent.", "If the reagent is such that it produces color or emits light when reacting to specific components, the components contained within the sample can be identified using optical methods.", "Depending on the properties of the reagent, other methods may also be used to identify components in the sample.", "The detection layer of the device of this invention is separated from the location (the water-swelling layer) where the sample is dropped to, so when the sample is flowing from the water-swelling layer to the detection layer, a specific component within the sample can be removed from the sample.", "An example would be separating out the corpuscles when blood is being assayed.", "Moreover, a second reagent, that differs from the reagent contained in the detection layer, can be put in the water-swelling layer.", "When the divider is composed of a water-repellent material, the reagent contained in the detection layer will not flow over onto the water-swelling layer until the reagent reacts with the sample, even if said reagent is a liquid.", "A suitable method for manufacturing the device of this invention comprises the following steps: (a) reforming the perimeter of a specific area on a surface of a support composed of an organic macromolecule so as to render it hydrophilic;", "(b) forming a divider composed of a water-repellent material on the reformed perimeter;", "(c) reforming the specific area and other area adjacent to the divider so as to render them hydrophilic;", "(d) affixing a detection layer and a water-swelling layer to the reformed specific area and another reformed area respectively, said detection layer containing reagent, said water-swelling layer expanding by absorbing water.", "This invention enables the refinement of the detection layer, by using the hydrophilic properties of the support to make a detection layer, a divider, and a water-swelling layer.", "Moreover, manufacturing costs are low, because there is no cutting and attaching work in the manufacturing process and a multiplicity of detection layers can be affixed simultaneously.", "BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A, 1B, 1C, 1D and 1E are perspective views that show the manufacturing process of an actual embodiment of the assay device.", "FIG. 2 is a sectional view of the assay device, taken along line II--II of FIG. 1E.", "FIG. 3 is a sectional view of the assay device in a operating condition, taken along line II--II of FIG. 1E.", "DESCRIPTION OF THE PREFERRED EMBODIMENTS An actual embodiment of this invention will be explained along with drawings.", "FIG. 1 shows the processing order used to manufacture the device of this invention.", "First, the organic macromolecule materials that are to comprise the support and the shape of the support are chosen.", "One or more of the following substances can be used as the organic macromolecule molecule: polyethylene, polypropylene, polystyrene, ABS, poly(vinyl chloride), poly(vinylidene chloride), thermoplastic polyurethane, poly(methyl methacrylate), polyoxyethylene, polycarbonate, polyamide, acetal resin, poly(phenyleneoxide), poly(butyleneterephthalate), poly(ethylene terephthalate), poly(phenylene sulfide), or other thermoplastic resins;", "unsaturated polyester resin, epoxy resin, phenol resin, urea resin, melamine resin, diallyl phthalate resin, or other thermosetting resins;", "styrene-butadiene rubber, polyisoprene rubber, natural rubber, or other rubbers.", "The shape of the support can be of sheet form, column form, cylinder form, membrane form, or any form that provides the areas on which to affix the detection layer and water-swelling layer.", "As shown in drawing FIG. 1A, the first areas 1a, where the detection layer is to be affixed, and the second area (to be explained below), where the water-swelling layer is to be affixed, are specified on the surface of the support 1, which is composed of organic macromolecule.", "In this example, the first areas are round in shape and the second area is a rectangle surrounding the first areas.", "The perimeters 1b of the respective first areas 1a are reformed so as to render them hydrophilic.", "The following methods can be used to reform parts of the support so as to render them hydrophilic: chemical processing which masks the surface of hydrophobic organic macromolecule, then chemically introduces hydrophilic groups or graft branches into exposed areas (where the mask does not cover the organic macromolecule) to render only the exposed areas hydrophilic;", "or plasma processing;", "corona discharge processing;", "UV irradiation;", "or other processing.", "Of these methods, irradiation with UV rays works well, because it requires no special pre- or post-processing and the necessary equipment is simple.", "A low-pressure mercury lamp is an ideal optimal source for the UV rays, because it has a low tube-wall temperature of approximately 100° C. and radiates high-energy, short wavelength UV rays.", "Short wavelength UV rays of 185 nm are good, because they have high energy, with the next best wave length being 254 nm.", "Irradiation should normally take place for a time period of from 1 to 120 minutes, at an irradiation distance of between 0.5 and 8 cm, and an illumination intensity of from 1 to 20 mW/cm 2 .", "Next, as shown in drawing FIG. 1B, dividers 2 composed of water-repellent material are formed on the reformed perimeters 1b.", "Good substance to use as the water-repellent material is a resin containing a function group that is bondable with carboxyl group or hydroxyl group, or a surface active agent.", "This is because molecules existing on the surface of the organic macromolecule prior to reforming, even carbon or hydrogen, are often substituted by the reforming into carboxyl or hydroxyl group.", "So, if the water-repellent material is a resin containing a function group that bonds chemically or physically with these molecules or if it is a surface active agent, it bonds with the reformed perimeter areas 1b and easily forms the dividers 2.", "Many kinds of this type of water-repellent material are known, such as silane coupling agent, fluorine compounded acrylic copolymer emulsion, amino-group denatured silicon oil, silane coupling agent--fluoroalkyl silicon chloride mixture, polyoxyalkylene denatured silicon oil, fluorine-based surface active agent, or fluorine silicon surface active agent.", "Following the formation of dividers 2, as shown in drawing FIG. 1C, the first areas 1a, which are surrounded by the dividers 2, and the rectangular second area 1c, which encloses the dividers 2, are reformed so as to render them hydrophilic.", "If UV irradiation is used to conduct the reforming, as noted above, a fluorine based or silicon based substance is good as the water-repellent material that composes the divider 2.", "This is because fluorine-based and silicon-based substances are inactive when exposed to UV light, so the function of the dividers 2 is not diminished by UV rays.", "The areas 1a and 1c may be reformed simultaneously, or separately with using a mask to block the UV rays.", "Even when the reforming is carried out separately for each area, if a fluorine or silicon based substance is used as the water-repellent material, the precision of the mask pattern is not required so strictly.", "Finally, a liquid made by solving the reagent is applied to the first areas 1a (drawing FIG. 1D) and gel composed of water-swelling material is applied to the second area 1c (drawing FIG. 1E).", "The water-swelling material can be, for example, water-absorptive resin, clay, or other inorganic compound in layer form.", "The liquid applied to the first areas 1a dries to become the detection layer 3.", "The gel applied to the second area 1c dries to become the water-swelling layer 4.", "The areas 1a and 1c can have their respective liquids applied simultaneously or one at a time.", "A perspective view diagram of the assay device obtained via the above-noted processes is shown in FIG. 1E.", "FIG. 2 is a sectional view taken on the line II--II of FIG. 1E.", "When this device is used to conduct an assay, drops of the liquid sample are applied onto the water-swelling layer 4.", "When the drops are applied, the water-swelling layer expands, extending over the dividers 2 and coming into contact with the detection layers 3.", "The liquid sample then moves by capillarity from the water-swelling layer 4 to the detection layer 3, where it reacts with the reagent.", "FIG. 3 shows the water-swelling layer 4 swelling and the detection layer 3 reacting with the liquid sample.", "To enable the assay of a multiplicity of items using a single assay device, a multiplicity of detection layers 3 may be made on a single support 1, each surrounded individually within a multiplicity of closed dividers 2 on the support 1.", "The drawings show a device made with the objective of simultaneously assaying two items.", "This enables the liquid sample to simultaneously flow from the water-swelling layer 4 into a multiplicity of detection layers 3, where it reacts separately with each of the reagent." ]
CROSS REFERENCE TO RELATED APPLICATION This patent application is a continuation of and claims priority to U.S. patent application Ser. No. 12/126,793, which is a divisional of U.S. patent application Ser. No. 09/976,475, filed Oct. 12, 2001, which claims a benefit and priority under 35 USC §119(e) to U.S. Provisional Application No. 60/297,817, filed Jun. 11, 2001, all of which are incorporated herein by reference in their entirety. BACKGROUND 1. Field of the Invention The present invention is related generally to a user interface for a personal digital assistant device. 2. Description of the Related Art Carrying a personal digital assistant (PDA) around is very convenient for tasks such as taking notes at a meeting or lecture, scheduling appointments, looking up addresses, and for performing a whole host of other functions. However, one function not easily performed with a PDA is that of telecommunications. A typical cellular telephone, meanwhile, offers a range of features, from speed dial to speakerphone to caller-ID, phonebook, etc. In order to have the functionality of a cellular telephone and the functionality of a PDA, consumers have generally had to choose from a selection of largely unsatisfactory options. The most common option is to carry both a PDA and cell phone. This is undesirable, however, because of the obvious impractical aspects of having to deal with two separate devices, both in terms of sheer bulk as well as the inconvenience of switching between units. Simply put, there are more things to buy, more things to break, and more things to lose. Another option is to purchase an add-on telephone device for a PDA. While this option is preferable to carrying two devices around, it still has limitations. For example, an add-on telephone device adds bulk to and changes the form factor of the PDA. In addition, since such a PDA must be designed to operate without an add-on telephone, the degree to which the user interface of the PDA can be integrated with the user interface of the add-on telephone is limited. Thus, an add-on solution is of only limited value, since there is not a true integration between the cellular telephone device and the PDA, but rather two separate devices at best co-existing side-by-side. Accordingly, what is needed is a system and method for providing a user interface to a device featuring integrated functionality of both a PDA and cellular telephone. SUMMARY OF THE INVENTION In accordance with the present invention there is provided a system and method for using an integrated device featuring functionality of both a PDA and cellular telephone. Features of the present invention include a power button offering control of both the computing and telephony functions of the device; a lid that turns the device on and off depending on its state, and can also be used to begin and terminate calls; a jog rocker that activates the device and is used to select from a variety of menu options; application buttons that offer direct access to applications stored on the device, and which can be configured to operate in conjunction with secondary keys to offer added functionality; an override-able ringer switch; a keyboard; and an Auto Word Completion function that verifies and corrects a user's typing in real time. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an illustration of a device with keyboard in accordance with an embodiment of the present invention. FIG. 2 is an illustration of a device without keyboard in accordance with an embodiment of the present invention. FIG. 3 is a flow chart illustrating power-on behavior of a device in accordance with an embodiment of the present invention. FIG. 4 is a flow chart illustrating power-off behavior of a device in accordance with an embodiment of the present invention. FIG. 5 is an illustration of a matrix describing behavior of a lid attached to a device in accordance with an embodiment of the present invention. FIGS. 6 a and 6 b are illustrations of a keyboard layout in accordance with an embodiment of the present invention. FIGS. 7 a and 7 b illustrates views of a display screen when Option mode and Option Lock mode are activate in accordance with an embodiment of the present invention. FIG. 8 is an illustration of a dialog box presented to a user when a call is incoming in accordance with one embodiment of the present invention. DETAILED DESCRIPTION In the discussion set forth below, for purposes of explanation, specific details are set forth in order to provide a thorough understanding of the invention. It will be appreciated by those skilled in the art that the present invention may be practiced without these specific details. In particular, those skilled in the art will appreciate that the methods described herein can be implemented in devices, systems and software other than the examples set forth. In other instances, conventional or otherwise well-known structures, devices, methods and techniques are referred to schematically or shown in block diagram form in order to facilitate description of the present invention. The present invention includes steps that may be embodied in machine-executable software instructions, and includes method steps that are implemented as a result of one or more processors executing such instructions. In other embodiments, hardware elements may be employed in place of, or in combination with, software instructions to implement the present invention. The software instructions may be stored in RAM or ROM, or on other media including removable media. The present invention includes a user interface for the operation of an integrated handheld personal computing device and wireless communication device. Referring now to FIG. 1 , there is shown an example of such an integrated device 100 . As illustrated in FIG. 1 , device 100 includes a base section 102 , a lid 104 , application and scroll buttons 106 , power button 110 , antenna 112 , jog rocker 114 , and ringer switch 116 , and display 118 . In addition, device 100 includes a keyboard 108 . As will be appreciated by those of skill in the art, the present invention may exist in a variety of embodiments, including embodiments in which the integrated device includes more or fewer physical components than are illustrated in FIG. 1 . For example, FIG. 2 illustrates another device 200 that does not have a keyboard, but instead has a writeable area 202 enabling input to the device 200 via, for example, a stylus. For convenience and clarity, device 100 of FIG. 1 serves as the illustration that will be referenced throughout this specification, but such reference should in no way be understood to restrict what is disclosed to such an embodiment. Device 100 includes an integrated GSM radio (also referred to as a cellular telephone), and while in alternative embodiments is of varying sizes and shapes, in one embodiment the device is designed to fit comfortably in a pocket. While the radio uses the GSM standard in one embodiment, in alternative embodiments the radio may use the CDMA standard, or any of a variety of other well-known wireless standards. Power Button Device 100 has a power button 110 , located in one embodiment on the top face, next to the antenna 112 . In one embodiment, the power button 110 performs the following functions: A single press and release of the power 110 button toggles device 100 on/off. Pressing and holding the power button 110 toggles the radio on/off. Double-tapping the power button 110 toggles a backlight on/off. Triple-tapping the power button 110 inverts the display 118 and insures that the backlight is on. A single press of the power button 110 when an incoming call is ringing silences the ring but does not turn off the device 100 . Referring now to FIG. 3 , there is shown a flowchart of the operation of the power button functionality starting from a device-off state. Initially, the device 100 is off and the power key is pressed 300 . If the key is being pressed for the first time within a given period 302 (e.g., it has not been pressed for at least the previous half second), the device 100 is switched on 304 . If the power button is held down for longer than a threshold amount of time, e.g., 1 second 306 then the radio is toggled on or off 308 . If the power button is held down for less than the threshold amount 306 , then upon release a countdown of predetermined length, e.g., ½ second, is begun 310 . If the power button is pressed 312 during the countdown, then the backlight is toggled on or off 314 . If the cycle is repeated and the power button is pressed for a third time during the countdown 312 , then the display 118 is inverted 316 , and the backlight is preferably turned on if it is not already on. If the power button is not pressed 312 during the countdown, then no additional actions take place as a result of the power button press. After the display is inverted in step 316 , the countdown is once again begun 318 . However, if the power button is pressed during this or subsequent countdowns 320 , the display is again inverted at step 316 . This countdown cycle continues until the power button is not pressed during the countdown 320 . Referring now to FIG. 4 , there is shown a flowchart of the operation of the power button functionality starting from a device-on state. Initially, the device is on, and the power key is pressed 400 . If the power key is being pressed for the first time 402 (e.g., it has not been pressed for at least the previous half second), no action is initially taken. If the power button is held down for longer than a threshold amount of time, e.g., 1 second 404 then the radio is toggled on or off 406 . If the power button is held down for less than the threshold amount 404 , then upon release a countdown of predetermined length, e.g., ½ second, is begun 408 . If the power button is not pressed 410 during the countdown, then the device is turned off 416 . If the power button is pressed 410 during the countdown, then the backlight is toggled on or off 412 . If the cycle is repeated and the power button is pressed for a third time during the countdown, then the display is inverted 414 , and the backlight is turned on if not already on. After the display is inverted 414 , another countdown is begun 416 . If the power button is pressed again 418 during the countdown, then the display is once again inverted 414 , and countdown 416 restarted. This continues until the countdown expires without the power button being pressed 418 . In addition, in one embodiment pressing the power button 110 when there is an incoming call silences the ring or vibrate. Further, if a call is in progress, pressing the power button turns off the device 100 but does not terminate the call. Finally, if the device is off when a call comes in, the device is turned on, and the backlight is illuminated, which helps to locate the device 100 , e.g., in a poorly-lit room. Lid Referring again to FIG. 1 , there is shown a view of device 100 , having a lid 104 attached to base 102 . In FIG. 1 , lid 104 is connected to base 102 via a hinge or other mechanism that allows lid 104 to open and close. Note that the lid 104 may be connected to base 102 in any of a variety of ways while still including features described herein. The particular embodiment of FIG. 1 is therefore meant to illustrate only one of many possible configurations. In one embodiment, lid 104 features a hardware switch for lid open and lid close detection, and may additionally include an integrated speaker for flip phone-like functionality. When closed, in one embodiment, lid 104 covers all of base 102 except for application and scroll buttons 106 . In one embodiment, lid 104 also includes a transparent window for viewing the display 118 of device 100 while the lid 104 is closed. The effect of opening and closing the lid 104 varies according to the state of device 100 at the time the lid 104 is opened or closed. In one embodiment, and referring now to FIG. 5 , opening and closing the lid 104 has the following effect: If the device is off, opening the lid turns on the device 100 , and launches 502 a predetermined application. In one embodiment, the predetermined application is a speed dial view of a telephone application, however in other embodiments the application can be any application on the device 100 , assignable by the user in one embodiment via a preferences control panel-type application. If the device is off, closing the lid has no effect 504 . If the device is on, then it is in one of three states: either a call is in progress, a call is incoming, or there is no call activity. If a call is incoming, then an incoming call notification is given to the user. An illustration of such a notification is shown in FIG. 8 . It will be appreciated that a user may be in the process of opening the lid when a call comes in. In such a situation, the user may not want to actually take the incoming call. For that reason, if the lid is opened within, in one embodiment, one second of the incoming call notification, no action is taken 506 (although the user can still answer the call in other ways, e.g., by tapping a dialog box 802 on the display of device 100 ). In other embodiments, the time may be shorter or longer than one second. If the lid is opened more than one second after the initial incoming call notification, then the call is answered 508 . Note also that in one embodiment a user can choose to accept or ignore any incoming telephone call by selecting the answer 802 or ignore 804 options presented in a popup dialog box. Similarly, if the user is in the process of closing the lid when a call comes in, it is desirable to assume that the lid is being closed not in response to the incoming call, but rather by coincidence. Thus if the lid is closed within an initial time, e.g., one second, of the first notification of an incoming call, no action is taken 510 . After this initial period, if the lid is closed, then in one embodiment the ring is silenced, the call is ignored, and the device is turned off 512 . During an active call, the lid is open in a preferred embodiment, unless a headset is plugged in. If a call is in progress and the headset is being used, then opening the lid has no effect on the call 514 . If the lid is closed while a headset call is in progress, the device is turned off, but the call is not disconnected 516 . If a telephone call is in progress without using a headset, then closing the lid hangs up the telephone, in one embodiment after displaying a warning message confirming that the call is about to be disconnected, and turns the device off 518 . During the confirmation warning message, the user has the opportunity to tell the device not to disconnect the call, e.g. by pressing the scroll-up button. In alternative embodiments, the call is disconnected as soon as the lid is closed. If a telephone call is not in progress, then in one embodiment, opening the lid when the device is already on has no effect 520 . That is, even if there is an application assigned to be launched upon the opening of the lid, when the power is already on, opening the lid does not launch the assigned application, but rather has no effect on what application is currently executing. Also, in one embodiment, if a call is not in progress, closing the lid turns the device off 522 . In addition, in one embodiment keyboard 108 is deactivated when the lid 104 is closed, whether the device 100 is on or off. This guards against inadvertent input to the device when pressure is applied to the lid, e.g., if the device is carried in a pocket, or if something heavy is placed on top of the device. In alternative embodiments, the keyboard 108 remains active at all times regardless of lid position. In one embodiment, application and scroll buttons 106 remain active even when the lid 104 is closed. This allows the scroll buttons to be used to respond to dialog boxes that may be presented to the user when the lid is closed. For example, if an alarm goes off, the user can dismiss the alarm by pressing a scroll button, instead of having to open the lid to tap the display 118 or press a button on the keyboard 108 . Tog Rocker Device 100 includes a jog rocker 114 such as is pictured in FIG. 1 . A jog rocker in one embodiment allows four input actions: up, down, press in, and press and hold. While individual applications provide specific responses to input from jog rocker 114 , in one embodiment pressing the jog rocker 114 when device 100 is turned off wakes device 100 up and launches a predefined application, such as the phone application in one embodiment. In one embodiment, this behavior is executed on jog rocker 114 press, not release, so that a press and hold of the jog rocker 114 wakes the device up, launches the predefined application on the press, and then executes within the application whatever that application has specified for a jog rocker 114 hold on the hold. In another embodiment, jog rocker 114 can be used to provide a scroll-up and scroll-down function similar to that provided by scroll buttons 106 . In one embodiment this is the default use for jog rocker 114 when an application does not provide additional functionality for the jog rocker. Ringer Switch Ringer switch 116 is used in a preferred embodiment to select whether incoming telephone calls should produce an audible ringing sound on device 100 . In a first position, device 100 produces such a ring tone, which is customizable in one embodiment using application software stored on device 100 . In a second position, device 100 does not produce a ring tone for an incoming call. In one embodiment, device 100 is configured to vibrate in response to an incoming telephone call. The vibrate feature of device 100 may additionally be activated by applications executing on device 100 , for example even when ringer switch 116 is in the first position (the audible ring position). In one embodiment, when ringer switch 116 is in the second position, all sounds made by device 100 are muted, and not just the ring tone. Thus, for example, while a number of applications executed on device 100 , e.g., an alarm, a message alert, etc., may instruct device 100 to produce a sound, the location of the switch in the second position will stop device 100 from actually making the sounds. In yet another embodiment, device 100 allows software resident on device 100 to override the physical setting of ringer switch 116 . This may be of particular use, for example, if the ringer switch is in the first position while a call is in progress and it is undesirable to have sounds from device 100 interfering with the call in an annoying fashion. Application Buttons A device such as device 100 typically has one or more application and scroll buttons 106 located physically on the device, providing direct access to applications associated with the buttons, as well as up-down and left-right scroll functionality. Using a keyboard 108 of device 100 , different applications are assignable to the application buttons 106 being pressed in combination with a modifier key. In one embodiment, an “option” key is the modifier key for these key combinations. In one embodiment, the following applications are mapped to option and (“+”) application button combinations: Option+Phone Application button maps to Memo Pad. Option+Calendar Application button maps to To-Do. Option+Internet Browser Application button maps to CityTime. Option+Messaging Application button maps to the calculator. In one embodiment, the Option+Application button key combination works both in series and in parallel. For example, pressing and releasing the Option button (a serial combination), then pressing an application button 106 launches the application that is mapped to that application button's option modification. Similarly, pressing and holding the Option button while pressing the application button 106 (a parallel combination) also launches that application button's option modification. If the option modification times out before the application button 106 is pressed, then the functionality is the same as if only the application button had been pressed. Pressing and holding Option, and then pressing an application button 106 while Option is still held down also launches the application that is mapped to that applications button's option modification. What occurs if the user continues to hold the application button in is controlled on an application-by-application basis. In one embodiment, the following application buttons 106 and combinations are mappable: a Phone Application button a Calendar Application button an Internet Browser Application button a Messaging Application button In alternative embodiments, the following combinations are also mappable: Option+Calendar Application button Option+Phone Application button Option+Internet Browser Application button Option+Messaging Application button Keyboard In one embodiment, keyboard 108 includes the following keys: a-z (26 keys) . (period) Symbol key Space Return Backspace Shift key Option key Menu key FIG. 6 a illustrates one embodiment of a keyboard 108 layout. In FIG. 6A , the bottom label of each key indicates its normal character, while the top left label indicates its shift key character, and the top right label indicates its option key character. FIG. 6 b illustrations just the number/punctuation keys extracted from FIG. 6 a . In an unmodified state, the keys produce the main character printed on them. In one embodiment, there is no on screen-modification state indicator for the unmodified keyboard state. In Shift state, the keys produce a capital version of the main character printed on them, as illustrated in FIG. 6 a . In Option state, the keys produce the alternate character illustrated in FIG. 6 b . In one embodiment, pressing the Option key once puts device 100 in Option state. Pressing Option in Option state puts the device in Option Lock state. Pressing Option in Option Lock state clears the state. Option state is canceled upon the entry of the Option-modified character. Option Lock state is not canceled upon the entry of the Option-modified character, hence the Lock-ness. Option state can be canceled without entering a character by pressing the Option key twice (once for lock, the second for clear) or pressing backspace. Note that in one embodiment, backspace cancels Option state, but not Option Lock state. Referring now to FIG. 7 a , in one embodiment, an on-screen modification state indicator 702 for Option state, which indicates to the user that the Option key has been pressed, is an oval tilted to have the same appearance as the shape of the Option key itself. Referring now to FIG. 7 b, the on-screen modification state indicator 704 for Option Lock state is similar to the Option state indicator except with a “bottom bar”. Holding down a key for a prolonged period causes the key to repeat. In one embodiment, all text entry has the same repeat rate, i.e. holding down the j produces j's at the same rate as holding down shift+j produces J's and option+j produces 5's. The Option and Shift keys both “time out” if additional input is not received within a prescribed period of time, e.g., 3 seconds in one embodiment. Note that in one embodiment the Option Lock and Shift Lock states do not time out. In addition, in a preferred embodiment, when the currently executing application on device 100 changes from a first application to a second application, the Shift state is cleared to avoid unintended Shifted input into the second application. Auto Word Completion In order to provide a fast and easy way to enter awkward or often-misspelled text, device 100 includes a word auto-completion/correction system that in one embodiment checks every word that a user enters against a database of common misspellings and convenient abbreviations and replaces the entered word with a preset correct or complete version of the word. For example, if a user enters ‘beleive’, it will automatically be replaced with ‘believe’. If a user enters ‘im’, it will be replaced with ‘I'm’. In one embodiment, Word Completion executes whenever a user enters any character that signals that they are finished typing the previous word, e.g.: Space Any punctuation Tab Return Next or Previous Field For instance, when a user types b,e,l,e,i,v,e the word ‘beleive’ is still displayed. If the user then enters a space (or any of the characters listed above) then ‘beleive’ is replaced by ‘believe’. Typing backspace once will erase the space (or tab, new line, etc.) that invoked the Word Completion. Typing backspace a second time will undo the word completion without deleting the last character of the word. At this point, typing any of the characters that usually invoke Word Completion will not invoke it again. If the replacement word in the database is not capitalized, then the capitalization of the word to be replaced is maintained. For instance, there is an entry in the Word Completion database that has the wrong word “feild” marked to be replaced with “field” so: feild becomes field Feild becomes Field If the replacement word in the database is capitalized, then the resulting word is capitalized no matter what the capitalization of the word to be replaced was. For instance, there is an entry in the Word Completion database that has the wrong word “im” marked to be replaced with “I'm” so: im becomes I'm Im becomes I'm Keyboard Navigation and Commands In one embodiment, device 100 switches off or “sleeps” in order to conserve power after a predefined period of time. In such circumstance, pressing a key on the keyboard 108 wakes the device back up, i.e. restoring the device to a power on state in the same condition that it was in prior to going to sleep. In other embodiments, waking the device 100 up is equivalent to a power on command, which starts the device with a predefined initial application. Note that the keys which will wake the device up may be predetermined, or may be changeable by the user. In one embodiment, some navigational activities of device 100 are keyboard enabled. Buttons such as “OK,” “Done,” and “Cancel” are mapped to certain keys and key combinations. Common actions, which may also be on-screen buttons like “New” and “Details . . . ,” are frequently included as menu items. These menu items have menu button+letter combinations assigned to them so that they may be executed easily from the keyboard 108 . In one embodiment, menus on device 100 are navigable via a menu key and menu mode. Pressing and releasing a dedicated hardware menu key on keyboard 108 displays a first pull-down menu of the current view. Pressing and releasing the menu key a second time dismisses the menu. While the menu is being displayed, in one embodiment the user can navigate the menus and execute menu items with the following actions: Scroll Up displays the next menu list to the right. Scroll Up from the last menu list scrolls back to the first. Holding Scroll Up repeats this action at the normal repeat rate. Scroll Down moves a highlight down through the current displayed list of menu items. If there is no highlighted item, such as when the menu list is first displayed, then the first press of Scroll Down highlights the first menu item. Scroll Down from the last menu item in the list scrolls back to the first item in the same list. Holding Scroll Down repeats this action at the normal repeat rate. Space executes the highlighted menu item on press. Return also executes the highlighted menu item on press. Backspace dismisses the menu. At any time when any menu is displayed, pressing any of the short cut letters executes the corresponding menu item, even if that menu item is in a menu list that is not currently displayed. Typing any character that is not detailed above or a short cut letter plays an error beep. At any time, whether or not a menu is displayed, pressing and holding the menu key and pressing a one of the shortcut letters executes the corresponding menu item, in one embodiment, without the menu being drawn on the screen. Pressing and releasing the menu key and then pressing the shortcut letter will display the menu, however, in one embodiment. Any menu that is being displayed is dismissed whenever a menu item is executed. Shift Lock and Option Lock are ignored when entering short cut letters. It is possible, however, to enter an option character as a short cut character in parallel: User presses the menu button to enter menu mode User presses and holds Option User presses x for instance The menu item with the short cut character ? would get executed, because the question mark (?) is formed by pressing Option-x. Pressing and releasing Option and then pressing x would execute the menu item with the short cut letter x. Menu mode itself will not clear the modification state, but the execution of a menu item may clear the modifications state depending on what that menu item does. User starts in Option Lock User presses the menu button User presses the menu button again to dismiss the menu The user should still be in Option Lock Thus, when buttons containing certain text are on the screen, certain keys or key combinations can be pressed that will execute the buttons as if they were pressed on the screen. The buttons that are mapped to the keyboard in one embodiment are: OK Done Cancel Yes No Next Previous The following four keys/key combinations are used for mapping to certain common on-screen buttons in one embodiment: Return Backspace Option+Return Option+Backspace Option+Return and Option+Backspace will work only in parallel. Globally, in one embodiment: Option+Return executes: OK Done Yes Next Send Accept Option+Backspace executes: Cancel No Previous Back Reject In one embodiment, if there is no opportunity for text entry on a particular screen, then the holding down of the Option key may be unnecessary. Thus, for example, within the context of alert dialogs: Return executes: OK Done Yes Next Send Accept Backspace executes: Cancel No Previous Back Reject Return and Backspace do not map to buttons in other contexts in one embodiment, since in other contexts there will likely be text areas in which Return and Backspace benefit from their normal functionality. In addition, in one embodiment the mappings described above also apply to non-English based applications. For example, Option+Return is mapped to “Oui” in a French language application. This allows a user to execute a foreign-language application on device 100 while providing similar functionality to an English-language application. The foregoing discloses exemplary methods and embodiments of the present invention. It will be understood that the invention may be embodied in other forms and variations without departing from the spirit or scope of the invention. Accordingly, this disclosure of the present invention is illustrative, but not limiting, of the invention, the scope of which is defined by the following claims.
An integrated device provides functionality of both a PDA and cellular telephone. Features include a power button offering control of both the computing and telephony functions of the device; a lid that turns the device on and off and controls additional telephony functions; a jog rocker that activates the device and is used to select from a variety of menu options; application buttons that offer direct access to applications stored on the device, and which can be configured to operate in conjunction with secondary keys to offer added functionality; a keyboard that enables data input into the device; an automatic word completion function that verifies and corrects a user's typing in real time; and a simplified keyboard navigation system that allows the navigation of menus using keyboard shortcuts.
Provide a concise summary of the essential information conveyed in the context.
[ "CROSS REFERENCE TO RELATED APPLICATION This patent application is a continuation of and claims priority to U.S. patent application Ser.", "No. 12/126,793, which is a divisional of U.S. patent application Ser.", "No. 09/976,475, filed Oct. 12, 2001, which claims a benefit and priority under 35 USC §119(e) to U.S. Provisional Application No. 60/297,817, filed Jun. 11, 2001, all of which are incorporated herein by reference in their entirety.", "BACKGROUND 1.", "Field of the Invention The present invention is related generally to a user interface for a personal digital assistant device.", "Description of the Related Art Carrying a personal digital assistant (PDA) around is very convenient for tasks such as taking notes at a meeting or lecture, scheduling appointments, looking up addresses, and for performing a whole host of other functions.", "However, one function not easily performed with a PDA is that of telecommunications.", "A typical cellular telephone, meanwhile, offers a range of features, from speed dial to speakerphone to caller-ID, phonebook, etc.", "In order to have the functionality of a cellular telephone and the functionality of a PDA, consumers have generally had to choose from a selection of largely unsatisfactory options.", "The most common option is to carry both a PDA and cell phone.", "This is undesirable, however, because of the obvious impractical aspects of having to deal with two separate devices, both in terms of sheer bulk as well as the inconvenience of switching between units.", "Simply put, there are more things to buy, more things to break, and more things to lose.", "Another option is to purchase an add-on telephone device for a PDA.", "While this option is preferable to carrying two devices around, it still has limitations.", "For example, an add-on telephone device adds bulk to and changes the form factor of the PDA.", "In addition, since such a PDA must be designed to operate without an add-on telephone, the degree to which the user interface of the PDA can be integrated with the user interface of the add-on telephone is limited.", "Thus, an add-on solution is of only limited value, since there is not a true integration between the cellular telephone device and the PDA, but rather two separate devices at best co-existing side-by-side.", "Accordingly, what is needed is a system and method for providing a user interface to a device featuring integrated functionality of both a PDA and cellular telephone.", "SUMMARY OF THE INVENTION In accordance with the present invention there is provided a system and method for using an integrated device featuring functionality of both a PDA and cellular telephone.", "Features of the present invention include a power button offering control of both the computing and telephony functions of the device;", "a lid that turns the device on and off depending on its state, and can also be used to begin and terminate calls;", "a jog rocker that activates the device and is used to select from a variety of menu options;", "application buttons that offer direct access to applications stored on the device, and which can be configured to operate in conjunction with secondary keys to offer added functionality;", "an override-able ringer switch;", "a keyboard;", "and an Auto Word Completion function that verifies and corrects a user's typing in real time.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an illustration of a device with keyboard in accordance with an embodiment of the present invention.", "FIG. 2 is an illustration of a device without keyboard in accordance with an embodiment of the present invention.", "FIG. 3 is a flow chart illustrating power-on behavior of a device in accordance with an embodiment of the present invention.", "FIG. 4 is a flow chart illustrating power-off behavior of a device in accordance with an embodiment of the present invention.", "FIG. 5 is an illustration of a matrix describing behavior of a lid attached to a device in accordance with an embodiment of the present invention.", "FIGS. 6 a and 6 b are illustrations of a keyboard layout in accordance with an embodiment of the present invention.", "FIGS. 7 a and 7 b illustrates views of a display screen when Option mode and Option Lock mode are activate in accordance with an embodiment of the present invention.", "FIG. 8 is an illustration of a dialog box presented to a user when a call is incoming in accordance with one embodiment of the present invention.", "DETAILED DESCRIPTION In the discussion set forth below, for purposes of explanation, specific details are set forth in order to provide a thorough understanding of the invention.", "It will be appreciated by those skilled in the art that the present invention may be practiced without these specific details.", "In particular, those skilled in the art will appreciate that the methods described herein can be implemented in devices, systems and software other than the examples set forth.", "In other instances, conventional or otherwise well-known structures, devices, methods and techniques are referred to schematically or shown in block diagram form in order to facilitate description of the present invention.", "The present invention includes steps that may be embodied in machine-executable software instructions, and includes method steps that are implemented as a result of one or more processors executing such instructions.", "In other embodiments, hardware elements may be employed in place of, or in combination with, software instructions to implement the present invention.", "The software instructions may be stored in RAM or ROM, or on other media including removable media.", "The present invention includes a user interface for the operation of an integrated handheld personal computing device and wireless communication device.", "Referring now to FIG. 1 , there is shown an example of such an integrated device 100 .", "As illustrated in FIG. 1 , device 100 includes a base section 102 , a lid 104 , application and scroll buttons 106 , power button 110 , antenna 112 , jog rocker 114 , and ringer switch 116 , and display 118 .", "In addition, device 100 includes a keyboard 108 .", "As will be appreciated by those of skill in the art, the present invention may exist in a variety of embodiments, including embodiments in which the integrated device includes more or fewer physical components than are illustrated in FIG. 1 .", "For example, FIG. 2 illustrates another device 200 that does not have a keyboard, but instead has a writeable area 202 enabling input to the device 200 via, for example, a stylus.", "For convenience and clarity, device 100 of FIG. 1 serves as the illustration that will be referenced throughout this specification, but such reference should in no way be understood to restrict what is disclosed to such an embodiment.", "Device 100 includes an integrated GSM radio (also referred to as a cellular telephone), and while in alternative embodiments is of varying sizes and shapes, in one embodiment the device is designed to fit comfortably in a pocket.", "While the radio uses the GSM standard in one embodiment, in alternative embodiments the radio may use the CDMA standard, or any of a variety of other well-known wireless standards.", "Power Button Device 100 has a power button 110 , located in one embodiment on the top face, next to the antenna 112 .", "In one embodiment, the power button 110 performs the following functions: A single press and release of the power 110 button toggles device 100 on/off.", "Pressing and holding the power button 110 toggles the radio on/off.", "Double-tapping the power button 110 toggles a backlight on/off.", "Triple-tapping the power button 110 inverts the display 118 and insures that the backlight is on.", "A single press of the power button 110 when an incoming call is ringing silences the ring but does not turn off the device 100 .", "Referring now to FIG. 3 , there is shown a flowchart of the operation of the power button functionality starting from a device-off state.", "Initially, the device 100 is off and the power key is pressed 300 .", "If the key is being pressed for the first time within a given period 302 (e.g., it has not been pressed for at least the previous half second), the device 100 is switched on 304 .", "If the power button is held down for longer than a threshold amount of time, e.g., 1 second 306 then the radio is toggled on or off 308 .", "If the power button is held down for less than the threshold amount 306 , then upon release a countdown of predetermined length, e.g., ½ second, is begun 310 .", "If the power button is pressed 312 during the countdown, then the backlight is toggled on or off 314 .", "If the cycle is repeated and the power button is pressed for a third time during the countdown 312 , then the display 118 is inverted 316 , and the backlight is preferably turned on if it is not already on.", "If the power button is not pressed 312 during the countdown, then no additional actions take place as a result of the power button press.", "After the display is inverted in step 316 , the countdown is once again begun 318 .", "However, if the power button is pressed during this or subsequent countdowns 320 , the display is again inverted at step 316 .", "This countdown cycle continues until the power button is not pressed during the countdown 320 .", "Referring now to FIG. 4 , there is shown a flowchart of the operation of the power button functionality starting from a device-on state.", "Initially, the device is on, and the power key is pressed 400 .", "If the power key is being pressed for the first time 402 (e.g., it has not been pressed for at least the previous half second), no action is initially taken.", "If the power button is held down for longer than a threshold amount of time, e.g., 1 second 404 then the radio is toggled on or off 406 .", "If the power button is held down for less than the threshold amount 404 , then upon release a countdown of predetermined length, e.g., ½ second, is begun 408 .", "If the power button is not pressed 410 during the countdown, then the device is turned off 416 .", "If the power button is pressed 410 during the countdown, then the backlight is toggled on or off 412 .", "If the cycle is repeated and the power button is pressed for a third time during the countdown, then the display is inverted 414 , and the backlight is turned on if not already on.", "After the display is inverted 414 , another countdown is begun 416 .", "If the power button is pressed again 418 during the countdown, then the display is once again inverted 414 , and countdown 416 restarted.", "This continues until the countdown expires without the power button being pressed 418 .", "In addition, in one embodiment pressing the power button 110 when there is an incoming call silences the ring or vibrate.", "Further, if a call is in progress, pressing the power button turns off the device 100 but does not terminate the call.", "Finally, if the device is off when a call comes in, the device is turned on, and the backlight is illuminated, which helps to locate the device 100 , e.g., in a poorly-lit room.", "Lid Referring again to FIG. 1 , there is shown a view of device 100 , having a lid 104 attached to base 102 .", "In FIG. 1 , lid 104 is connected to base 102 via a hinge or other mechanism that allows lid 104 to open and close.", "Note that the lid 104 may be connected to base 102 in any of a variety of ways while still including features described herein.", "The particular embodiment of FIG. 1 is therefore meant to illustrate only one of many possible configurations.", "In one embodiment, lid 104 features a hardware switch for lid open and lid close detection, and may additionally include an integrated speaker for flip phone-like functionality.", "When closed, in one embodiment, lid 104 covers all of base 102 except for application and scroll buttons 106 .", "In one embodiment, lid 104 also includes a transparent window for viewing the display 118 of device 100 while the lid 104 is closed.", "The effect of opening and closing the lid 104 varies according to the state of device 100 at the time the lid 104 is opened or closed.", "In one embodiment, and referring now to FIG. 5 , opening and closing the lid 104 has the following effect: If the device is off, opening the lid turns on the device 100 , and launches 502 a predetermined application.", "In one embodiment, the predetermined application is a speed dial view of a telephone application, however in other embodiments the application can be any application on the device 100 , assignable by the user in one embodiment via a preferences control panel-type application.", "If the device is off, closing the lid has no effect 504 .", "If the device is on, then it is in one of three states: either a call is in progress, a call is incoming, or there is no call activity.", "If a call is incoming, then an incoming call notification is given to the user.", "An illustration of such a notification is shown in FIG. 8 .", "It will be appreciated that a user may be in the process of opening the lid when a call comes in.", "In such a situation, the user may not want to actually take the incoming call.", "For that reason, if the lid is opened within, in one embodiment, one second of the incoming call notification, no action is taken 506 (although the user can still answer the call in other ways, e.g., by tapping a dialog box 802 on the display of device 100 ).", "In other embodiments, the time may be shorter or longer than one second.", "If the lid is opened more than one second after the initial incoming call notification, then the call is answered 508 .", "Note also that in one embodiment a user can choose to accept or ignore any incoming telephone call by selecting the answer 802 or ignore 804 options presented in a popup dialog box.", "Similarly, if the user is in the process of closing the lid when a call comes in, it is desirable to assume that the lid is being closed not in response to the incoming call, but rather by coincidence.", "Thus if the lid is closed within an initial time, e.g., one second, of the first notification of an incoming call, no action is taken 510 .", "After this initial period, if the lid is closed, then in one embodiment the ring is silenced, the call is ignored, and the device is turned off 512 .", "During an active call, the lid is open in a preferred embodiment, unless a headset is plugged in.", "If a call is in progress and the headset is being used, then opening the lid has no effect on the call 514 .", "If the lid is closed while a headset call is in progress, the device is turned off, but the call is not disconnected 516 .", "If a telephone call is in progress without using a headset, then closing the lid hangs up the telephone, in one embodiment after displaying a warning message confirming that the call is about to be disconnected, and turns the device off 518 .", "During the confirmation warning message, the user has the opportunity to tell the device not to disconnect the call, e.g. by pressing the scroll-up button.", "In alternative embodiments, the call is disconnected as soon as the lid is closed.", "If a telephone call is not in progress, then in one embodiment, opening the lid when the device is already on has no effect 520 .", "That is, even if there is an application assigned to be launched upon the opening of the lid, when the power is already on, opening the lid does not launch the assigned application, but rather has no effect on what application is currently executing.", "Also, in one embodiment, if a call is not in progress, closing the lid turns the device off 522 .", "In addition, in one embodiment keyboard 108 is deactivated when the lid 104 is closed, whether the device 100 is on or off.", "This guards against inadvertent input to the device when pressure is applied to the lid, e.g., if the device is carried in a pocket, or if something heavy is placed on top of the device.", "In alternative embodiments, the keyboard 108 remains active at all times regardless of lid position.", "In one embodiment, application and scroll buttons 106 remain active even when the lid 104 is closed.", "This allows the scroll buttons to be used to respond to dialog boxes that may be presented to the user when the lid is closed.", "For example, if an alarm goes off, the user can dismiss the alarm by pressing a scroll button, instead of having to open the lid to tap the display 118 or press a button on the keyboard 108 .", "Tog Rocker Device 100 includes a jog rocker 114 such as is pictured in FIG. 1 .", "A jog rocker in one embodiment allows four input actions: up, down, press in, and press and hold.", "While individual applications provide specific responses to input from jog rocker 114 , in one embodiment pressing the jog rocker 114 when device 100 is turned off wakes device 100 up and launches a predefined application, such as the phone application in one embodiment.", "In one embodiment, this behavior is executed on jog rocker 114 press, not release, so that a press and hold of the jog rocker 114 wakes the device up, launches the predefined application on the press, and then executes within the application whatever that application has specified for a jog rocker 114 hold on the hold.", "In another embodiment, jog rocker 114 can be used to provide a scroll-up and scroll-down function similar to that provided by scroll buttons 106 .", "In one embodiment this is the default use for jog rocker 114 when an application does not provide additional functionality for the jog rocker.", "Ringer Switch Ringer switch 116 is used in a preferred embodiment to select whether incoming telephone calls should produce an audible ringing sound on device 100 .", "In a first position, device 100 produces such a ring tone, which is customizable in one embodiment using application software stored on device 100 .", "In a second position, device 100 does not produce a ring tone for an incoming call.", "In one embodiment, device 100 is configured to vibrate in response to an incoming telephone call.", "The vibrate feature of device 100 may additionally be activated by applications executing on device 100 , for example even when ringer switch 116 is in the first position (the audible ring position).", "In one embodiment, when ringer switch 116 is in the second position, all sounds made by device 100 are muted, and not just the ring tone.", "Thus, for example, while a number of applications executed on device 100 , e.g., an alarm, a message alert, etc.", ", may instruct device 100 to produce a sound, the location of the switch in the second position will stop device 100 from actually making the sounds.", "In yet another embodiment, device 100 allows software resident on device 100 to override the physical setting of ringer switch 116 .", "This may be of particular use, for example, if the ringer switch is in the first position while a call is in progress and it is undesirable to have sounds from device 100 interfering with the call in an annoying fashion.", "Application Buttons A device such as device 100 typically has one or more application and scroll buttons 106 located physically on the device, providing direct access to applications associated with the buttons, as well as up-down and left-right scroll functionality.", "Using a keyboard 108 of device 100 , different applications are assignable to the application buttons 106 being pressed in combination with a modifier key.", "In one embodiment, an “option”", "key is the modifier key for these key combinations.", "In one embodiment, the following applications are mapped to option and (“+”) application button combinations: Option+Phone Application button maps to Memo Pad.", "Option+Calendar Application button maps to To-Do.", "Option+Internet Browser Application button maps to CityTime.", "Option+Messaging Application button maps to the calculator.", "In one embodiment, the Option+Application button key combination works both in series and in parallel.", "For example, pressing and releasing the Option button (a serial combination), then pressing an application button 106 launches the application that is mapped to that application button's option modification.", "Similarly, pressing and holding the Option button while pressing the application button 106 (a parallel combination) also launches that application button's option modification.", "If the option modification times out before the application button 106 is pressed, then the functionality is the same as if only the application button had been pressed.", "Pressing and holding Option, and then pressing an application button 106 while Option is still held down also launches the application that is mapped to that applications button's option modification.", "What occurs if the user continues to hold the application button in is controlled on an application-by-application basis.", "In one embodiment, the following application buttons 106 and combinations are mappable: a Phone Application button a Calendar Application button an Internet Browser Application button a Messaging Application button In alternative embodiments, the following combinations are also mappable: Option+Calendar Application button Option+Phone Application button Option+Internet Browser Application button Option+Messaging Application button Keyboard In one embodiment, keyboard 108 includes the following keys: a-z (26 keys) .", "(period) Symbol key Space Return Backspace Shift key Option key Menu key FIG. 6 a illustrates one embodiment of a keyboard 108 layout.", "In FIG. 6A , the bottom label of each key indicates its normal character, while the top left label indicates its shift key character, and the top right label indicates its option key character.", "FIG. 6 b illustrations just the number/punctuation keys extracted from FIG. 6 a .", "In an unmodified state, the keys produce the main character printed on them.", "In one embodiment, there is no on screen-modification state indicator for the unmodified keyboard state.", "In Shift state, the keys produce a capital version of the main character printed on them, as illustrated in FIG. 6 a .", "In Option state, the keys produce the alternate character illustrated in FIG. 6 b .", "In one embodiment, pressing the Option key once puts device 100 in Option state.", "Pressing Option in Option state puts the device in Option Lock state.", "Pressing Option in Option Lock state clears the state.", "Option state is canceled upon the entry of the Option-modified character.", "Option Lock state is not canceled upon the entry of the Option-modified character, hence the Lock-ness.", "Option state can be canceled without entering a character by pressing the Option key twice (once for lock, the second for clear) or pressing backspace.", "Note that in one embodiment, backspace cancels Option state, but not Option Lock state.", "Referring now to FIG. 7 a , in one embodiment, an on-screen modification state indicator 702 for Option state, which indicates to the user that the Option key has been pressed, is an oval tilted to have the same appearance as the shape of the Option key itself.", "Referring now to FIG. 7 b, the on-screen modification state indicator 704 for Option Lock state is similar to the Option state indicator except with a “bottom bar.”", "Holding down a key for a prolonged period causes the key to repeat.", "In one embodiment, all text entry has the same repeat rate, i.e. holding down the j produces j's at the same rate as holding down shift+j produces J's and option+j produces 5's.", "The Option and Shift keys both “time out”", "if additional input is not received within a prescribed period of time, e.g., 3 seconds in one embodiment.", "Note that in one embodiment the Option Lock and Shift Lock states do not time out.", "In addition, in a preferred embodiment, when the currently executing application on device 100 changes from a first application to a second application, the Shift state is cleared to avoid unintended Shifted input into the second application.", "Auto Word Completion In order to provide a fast and easy way to enter awkward or often-misspelled text, device 100 includes a word auto-completion/correction system that in one embodiment checks every word that a user enters against a database of common misspellings and convenient abbreviations and replaces the entered word with a preset correct or complete version of the word.", "For example, if a user enters ‘beleive’, it will automatically be replaced with ‘believe’.", "If a user enters ‘im’, it will be replaced with ‘I'm’.", "In one embodiment, Word Completion executes whenever a user enters any character that signals that they are finished typing the previous word, e.g.: Space Any punctuation Tab Return Next or Previous Field For instance, when a user types b,e,l,e,i,v,e the word ‘beleive’ is still displayed.", "If the user then enters a space (or any of the characters listed above) then ‘beleive’ is replaced by ‘believe’.", "Typing backspace once will erase the space (or tab, new line, etc.) that invoked the Word Completion.", "Typing backspace a second time will undo the word completion without deleting the last character of the word.", "At this point, typing any of the characters that usually invoke Word Completion will not invoke it again.", "If the replacement word in the database is not capitalized, then the capitalization of the word to be replaced is maintained.", "For instance, there is an entry in the Word Completion database that has the wrong word “feild”", "marked to be replaced with “field”", "so: feild becomes field Feild becomes Field If the replacement word in the database is capitalized, then the resulting word is capitalized no matter what the capitalization of the word to be replaced was.", "For instance, there is an entry in the Word Completion database that has the wrong word “im”", "marked to be replaced with “I'm”", "so: im becomes I'm Im becomes I'm Keyboard Navigation and Commands In one embodiment, device 100 switches off or “sleeps”", "in order to conserve power after a predefined period of time.", "In such circumstance, pressing a key on the keyboard 108 wakes the device back up, i.e. restoring the device to a power on state in the same condition that it was in prior to going to sleep.", "In other embodiments, waking the device 100 up is equivalent to a power on command, which starts the device with a predefined initial application.", "Note that the keys which will wake the device up may be predetermined, or may be changeable by the user.", "In one embodiment, some navigational activities of device 100 are keyboard enabled.", "Buttons such as “OK,” “Done,” and “Cancel”", "are mapped to certain keys and key combinations.", "Common actions, which may also be on-screen buttons like “New”", "and “Details . . . ,” are frequently included as menu items.", "These menu items have menu button+letter combinations assigned to them so that they may be executed easily from the keyboard 108 .", "In one embodiment, menus on device 100 are navigable via a menu key and menu mode.", "Pressing and releasing a dedicated hardware menu key on keyboard 108 displays a first pull-down menu of the current view.", "Pressing and releasing the menu key a second time dismisses the menu.", "While the menu is being displayed, in one embodiment the user can navigate the menus and execute menu items with the following actions: Scroll Up displays the next menu list to the right.", "Scroll Up from the last menu list scrolls back to the first.", "Holding Scroll Up repeats this action at the normal repeat rate.", "Scroll Down moves a highlight down through the current displayed list of menu items.", "If there is no highlighted item, such as when the menu list is first displayed, then the first press of Scroll Down highlights the first menu item.", "Scroll Down from the last menu item in the list scrolls back to the first item in the same list.", "Holding Scroll Down repeats this action at the normal repeat rate.", "Space executes the highlighted menu item on press.", "Return also executes the highlighted menu item on press.", "Backspace dismisses the menu.", "At any time when any menu is displayed, pressing any of the short cut letters executes the corresponding menu item, even if that menu item is in a menu list that is not currently displayed.", "Typing any character that is not detailed above or a short cut letter plays an error beep.", "At any time, whether or not a menu is displayed, pressing and holding the menu key and pressing a one of the shortcut letters executes the corresponding menu item, in one embodiment, without the menu being drawn on the screen.", "Pressing and releasing the menu key and then pressing the shortcut letter will display the menu, however, in one embodiment.", "Any menu that is being displayed is dismissed whenever a menu item is executed.", "Shift Lock and Option Lock are ignored when entering short cut letters.", "It is possible, however, to enter an option character as a short cut character in parallel: User presses the menu button to enter menu mode User presses and holds Option User presses x for instance The menu item with the short cut character ?", "would get executed, because the question mark (?) is formed by pressing Option-x.", "Pressing and releasing Option and then pressing x would execute the menu item with the short cut letter x. Menu mode itself will not clear the modification state, but the execution of a menu item may clear the modifications state depending on what that menu item does.", "User starts in Option Lock User presses the menu button User presses the menu button again to dismiss the menu The user should still be in Option Lock Thus, when buttons containing certain text are on the screen, certain keys or key combinations can be pressed that will execute the buttons as if they were pressed on the screen.", "The buttons that are mapped to the keyboard in one embodiment are: OK Done Cancel Yes No Next Previous The following four keys/key combinations are used for mapping to certain common on-screen buttons in one embodiment: Return Backspace Option+Return Option+Backspace Option+Return and Option+Backspace will work only in parallel.", "Globally, in one embodiment: Option+Return executes: OK Done Yes Next Send Accept Option+Backspace executes: Cancel No Previous Back Reject In one embodiment, if there is no opportunity for text entry on a particular screen, then the holding down of the Option key may be unnecessary.", "Thus, for example, within the context of alert dialogs: Return executes: OK Done Yes Next Send Accept Backspace executes: Cancel No Previous Back Reject Return and Backspace do not map to buttons in other contexts in one embodiment, since in other contexts there will likely be text areas in which Return and Backspace benefit from their normal functionality.", "In addition, in one embodiment the mappings described above also apply to non-English based applications.", "For example, Option+Return is mapped to “Oui”", "in a French language application.", "This allows a user to execute a foreign-language application on device 100 while providing similar functionality to an English-language application.", "The foregoing discloses exemplary methods and embodiments of the present invention.", "It will be understood that the invention may be embodied in other forms and variations without departing from the spirit or scope of the invention.", "Accordingly, this disclosure of the present invention is illustrative, but not limiting, of the invention, the scope of which is defined by the following claims." ]
BACKGROUND 1. Field of the Invention This invention relates generally to the field of air filtering for buildings and more specifically to the filtering of carbon monoxide from air. 2. Description of the Related Art It is undesirable to have carbon monoxide present in the breathable air of commercial or private buildings. However, various small amounts of this poisonous gas are always present since it is produced by automobiles and other industrial processes. Prior filtering techniques for carbon monoxide have generally required either passing the gas over a catalyst at high temperatures to convert it to carbon dioxide, or else trapping the gas in some sort of absorptive medium. Both of these techniques are undesirable for continuous filtering of building air. The first method requires considerable energy to heat the catalyst material; the second requires frequent replacement of the filter material. A filter with high energy usage and high temperatures is particularly undesirable for a residence where energy costs and safety are both very important. Any filter that requires periodic replacement of its internal parts is undesirable from a cost standpoint. It is also fairly well established that filters that require periodic maintenance may not be well maintained in practice. Titanium dioxide, along with other materials, is a well known catalyst, and has used been along with a reducing agent, to reduce nitrogen oxides in flue gas (Vogel et al. U.S. Pat. No. 5,225,390). It has also been used as a basis for catalysts that oxidize carbon monoxide and various hydrocarbons (Vorob'iev U.S. Pat. No. 5,204,309). However, to accomplish this, gas temperatures must be higher than 100 degrees C. A typical temperature range is 100 degrees C. to 300 degrees C. It is known in the art of liquid filtering that titanium dioxide possesses the property of photo-catalytic activity. Here, the titanium dioxide becomes excited by ultraviolet light to act as a very effective catalyst to oxidize hydrocarbons, in solution. A disc of borosilicate glass can be coated with anatase titanium dioxide. Such a reactor can be spun at high RPM in the presence of ultraviolet light while liquids containing photocatalytically degradable organic material are applied to the disk (Urwin et al. U.S. Pat. No. 5,308,458). Dry titanium dioxide has been used to convert ethane to carbon dioxide and water (Daroux et al. Canadian J. of Chem. Eng. vol 63, Aug. 85). What is badly needed in the field of indoor air quality and HVAC is a low priced passive filter for carbon monoxide in air that works at room temperature and does not become contaminated so as to require periodic replacement or maintenance. This filter should function in a dry state and not require moving parts. It should remove most of the carbon monoxide normally present in breathable air as this air is passed through it at a reasonable flow rate. In addition, the filter should be simple to manufacture. SUMMARY OF THE INVENTION A tube, bulb, flat tile, or other reaction chamber is filled with a fine fibrous material such as fiberglass that has been coated with titanium dioxide. Embedded in the mesh of fibrous material is a source of ultraviolet light that excites the titanium dioxide into a photocatalytic state. Incident photons create electron-hole pairs in the titanium dioxide forming an active surface that has an affinity for oxygen molecules. When a CO molecule attaches to the titanium oxide-oxygen radical, the entire complex oxidizes the CO to carbon dioxide, a stable compound which is then released. Thus incoming carbon monoxide is effectively oxidized to carbon dioxide. There is no poisoning or degradation of the titanium dioxide in the filter by this process. Since carbon dioxide in low concentrations in breathable air is not objectionable, the filter converts a poisonous, very undesirable gas, to a stable, not undesirable one. One embodiment of the present invention is to form filter plates several feet square of the fibrous filter material. Each plate can contain a UV source, or the light can be piped into the material with lossy fiber optics (light fibers that loose light through their outer walls). The lossy light fibers themselves can be coated with titanium dioxide which becomes photocatalytic anytime UV light is in the fiber. Such lossy fibers can be formed into flat plates or placed in a bulb or chamber. The fiber ends can be terminated in a UV reflector to cause light reaching the fiber end to travel backward down the fiber and more efficiently defuse into the titanium dioxide. Such filters can be placed into the airflow of a building HVAC system to effectively remove CO from the circulating air supply of a building. These filters also have uses for filtering carbon monoxide from flow gases in pipes. BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of this invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention. FIG. 1 is a schematic diagram showing a bulb or reaction chamber filled with titanium dioxide and illuminated with an internal ultraviolet light source. FIG. 2 shows a conceptual design for a possible reaction chamber. FIG. 3 is a diagram showing the essential steps of the dry titanium dioxide photocatalytic chemistry as carbon monoxide is converted to carbon dioxide. FIG. 4 shows a flat plate filter suitable for HVAC systems. FIG. 5 shows another flat plate filter suitable for use in HVAC systems. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. DESCRIPTION OF PREFERRED EMBODIMENTS The carbon monoxide filter is shown schematically in FIG. 1. Here a reaction chamber 1 forming a closed area is filled with a web or matrix of inert material 3. This inert material must be such that it can hold titanium dioxide and in addition not react with incoming air. Its most important property is that it provide mechanical support for the powered titanium dioxide. An addition, it should not be oxidized by the passage of moisture. Also, since the titanium dioxide is excited by light photons, this material should not compete for photons. A simple fibrous material such as fiber glass make by Owens Corning is quite sufficient. However, the invention is not limited to the use of fiberglass; any fibrous material capable of holding powdered titanium dioxide, either with and adhesive, or without, is acceptable and may be incorporated into the present invention. The web or fibrous material 3 is coated with anatase titanium dioxide that is applied in the form of a fine powder. The particle size can vary over a wide range. The important feature of the titanium dioxide is that there be sufficient surface area to absorb photons and interact with the carbon monoxide present in air. High dispersion pigment grade anatase titanium dioxide having a specific surface area of from about 10 to 50 square meters per gram is entirely adequate. This material is provided commercially as type AO-1 by Chimex Technology Co. of Uzbekistan and other companies. Titanium dioxide in rutile form having a surface area of less than 10 square meters per gram does not have enough surface area for use in the present invention. It is possible to use anatase material as fine as 200 square meters per gram. In general, the more surface area, the better. The titanium dioxide must be made to adhere to the fibrous matrix. In a dense matrix, the powder may simply be sprayed in. However, this technique may not totally coat the fibers with the density desired. A better method is to immerse the matrix in a low viscosity adhesive liquid so that most fiber surfaces wet. Then the powdered titanium dioxide will adhere to the fibers. As the adhesive sets, the titanium dioxide becomes glued to the surface of the fibers. The initial bath must not form globs that plug the matrix. It is possible to blow excess adhesive from the matrix with compressed air before blowing in titanium dioxide powder. Any method that deposits a high surface area of titanium dioxide into the matrix satisfies the present invention. An ultraviolet optical source 2 is mounted in the chamber. This source supplies photons to excite the titanium dioxide in the mesh 3 to a photocatalytic state as explained in the next section. This optical source 2 should supply a wavelength shorter than 360 nm since this wavelength represents the cutoff energy for semiconductor bandgap excitation in titanium dioxide. A mercury lamp such as a Hanovia 450 Watt lamp is sufficient but may require more power than is necessary since it is only necessary to supply enough photons to excite most of the surface area of the titanium dioxide. It is entirely possible to use lower power low-pressure UV lamps in the present invention. To fully excite the titanium dioxide, it is desirable to achieve a photon flux of between 0.5-1.3 times 10 to the 15 photons per square cm per second. However, the present invention will work satisfactorily at lower intensities. Air containing carbon monoxide enters the reaction chamber through an orifice 4; the CO reacts with the titanium dioxide, and air containing the resulting carbon dioxide exits from a second orifice 5. The maximum flow rate depends of such factors as the total surface area of the titanium dioxide, the concentration of CO in the incoming air, the degree of conversion required, and the intensity of the UV optical source. An alternative embodiment of the present invention suitable for an HVAC duct can be made from a frame containing the fibrous material (see FIG. 4). FIG. 2 shows a reaction chamber for removing carbon monoxide from air that is piped. Incoming air enter a first orifice 4, interacts with a matrix containing titanium dioxide 3 and exits from a second orifice 5. An ultraviolet light source 2 is embedded in the matrix to supply photons to the titanium dioxide. The UV light source 2 is powered by wires 6A and 6B from its electrodes 7A and 7B. These wires 6 run to external electrodes 8A and 8B from where they are attached to a power supply. FIG. 3 shows schematically the titanium dioxide surface photochemistry involved in oxidation of carbon monoxide to carbon dioxide. The outer electron orbitals of pure titanium contain two 3d electrons and two 4s electrons. In the oxide these four electrons from partially covalent and partially ionic bonds with two oxygen atoms. The two 3d electrons are no longer in the 3d band of the titanium atom, but in the 2p band of the extra oxygen. This bonding is ionic. Since the 3d band of pure titanium dioxide is empty, the pure oxide is an insulator. Slight impurities create holes in the oxygen 2p band and conduction electrons in the titanium 3d band to make the slightly impure material an extrinsic semiconductor. The material normally appears as an n type semiconductor since the typical impurities lead to an excess of conduction electrons. Excitation of this band structure by a photon of sufficient energy creates extra holes and electrons in pairs as an electron from the valance band is excited to the conduction band. The bandgap energy is approximately 3.45 electron volts. Thus the wavelength of the exciting UV light must be shorter than 360 nm. In FIG. 3, titanium dioxide 9 is excited by photons of sufficient energy 10 producing extra hole and electron pairs 11. In the presence of an electrophilic compound such as oxygen gas molecules, the solid surface is covered by negative adsorbed molecules. Therefore, the photo-produced hole is attracted to the surface by the electric field thus created. Under these conditions, the semiconductor becomes capable of separating the photo-produced charges and can behave as a photo-catalyst. Maintenance of electrical neutrality is achieved either by direct charge recombination or by an equilibrium between the holes reacting with an oxidizable negative species and electrons captured by a reducible species. Thus in FIG. 3, oxygen molecules 12 are attracted to the surface of the excited titanium dioxide 13. Conduction electrons convert O2 molecules to adsorbed O2 radicals. Holes convert the adsorbed molecules to single adsorbed O atoms at the surface. Carbon monoxide 14 attaches briefly to this complex 15\16. The adsorbed oxygen atom reacts immediately to form carbon dioxide 17, and the titanium dioxide 18 remains unchanged from its initial state 18. The reaction continues in equilibrium at the surface of the titanium dioxide as long as there are enough photons to keep the catalyst excited, and enough carbon monoxide to convert to carbon dioxide. In the absence of carbon monoxide or other compounds to convert, and the in the continued presence of sufficient photons, the excited titanium dioxide-oxygen complex 13 is relatively stable. FIG. 4 shows a filter suitable for use in a duct associated with an HVAC system. A frame 19 of some suitable support material such as wood holds a matrix of fibers 3 that are coated with titanium dioxide. The filter is divided into tiles, and each tile contains an ultraviolet light source 2 to photo-excite the titanium dioxide in that tile. The fibrous material, which can be fiberglass or similar material, is from 0.5 to several inches thick. Normal HVAC flow rates through such tiles significantly reduce the amount of carbon monoxide in building air. The filter does not poison or degrade with time. However, air entering the filter should be prefiltered to first remove particulate matter that might lodge in the carbon monoxide filter. An alternative method of supplying UV light to the filter matrix is to use lossy optical waveguides. Here UV light of sufficient intensity and energy is launched into the fiber as with any other light fiber; however, the fiber is constructed with a particularly thin cladding that allows light to leak. Also there is very little difference (if any) in refractive index between the core and the cladding. Multimode plastic fibers that pass ultraviolet are particularly suitable for this application. The end of such a fiber should preferably contain a reflector so that there is no light loss from the fiber end; rather, the light diffuses out along the fiber in a uniform fashion. It is also possible to attach the titanium dioxide directly to these fibers providing the outer or reacting surface of the catalyst is exposed to enough light to become photo-excited. FIG. 5 shows another flat plate filter suitable for use in an air duct in a HVAC system. Fibrous material coated with titanium dioxide 3 is placed in a flat frame several inches thick. The fibrous material may be fiber glass or any other fiber web capable of holding titanium dioxide powder. A particularly attractive material is zeolite which is a chemical matrix capable of holding other compounds in its structure. The zeolite or zeolite membrane is pretreated with titanium dioxide before it is placed in the matrix 3. A UV light source 2 illuminates and photo-excites the titanium dioxide 3. Behind the UV light source 2 is an optional reflector 21 that causes most of the light from the source to impinge upon the titanium dioxide 3. Upstream of the titanium dioxide matrix 3 is an optional layer of volatile organic compound (VOC) capture medium. This optional layer 20 allows the filter to also remove VOC contaminants from the air along with carbon monoxide. This captive 20 medium, since it is "sticky", can be used to hold some or all of the titanium dioxide to increase carbon monoxide removal if desired. If titanium dioxide is used on such a sticky layer, means must be provided to illuminate it so it becomes photoexcited. The filtering medium holding the titanium dioxide may take the form of fibers, pellets, or coated surfaces of all types.
A reaction chamber is filled with a fine fibrous material capable of holding powdered anatase titanium dioxide. Embedded in the fibrous mesh is a source of ultraviolet light that is used to photo-excite the titanium dioxide. Air containing carbon monoxide is passed through the reaction chamber, and carbon monoxide is oxidized to carbon dioxide which then passes out of the filter. An alternative embodiment is a rectangular plate several feet square containing fibrous material containing titanium dioxide. Ultraviolet light impinges on the fibrous material photo-exciting the titanium dioxide. When air from an HVAC system is passed through the filter, carbon monoxide is oxidized into carbon dioxide and thus effectively removed from the air. Ultraviolet light can alternatively be supplied to the filter via lossy optical waveguides or fiber optics. These waveguides may be coated with titanium dioxide or the titanium dioxide may be separately suspended in the filter.
Briefly summarize the invention's components and working principles as described in the document.
[ "BACKGROUND 1.", "Field of the Invention This invention relates generally to the field of air filtering for buildings and more specifically to the filtering of carbon monoxide from air.", "Description of the Related Art It is undesirable to have carbon monoxide present in the breathable air of commercial or private buildings.", "However, various small amounts of this poisonous gas are always present since it is produced by automobiles and other industrial processes.", "Prior filtering techniques for carbon monoxide have generally required either passing the gas over a catalyst at high temperatures to convert it to carbon dioxide, or else trapping the gas in some sort of absorptive medium.", "Both of these techniques are undesirable for continuous filtering of building air.", "The first method requires considerable energy to heat the catalyst material;", "the second requires frequent replacement of the filter material.", "A filter with high energy usage and high temperatures is particularly undesirable for a residence where energy costs and safety are both very important.", "Any filter that requires periodic replacement of its internal parts is undesirable from a cost standpoint.", "It is also fairly well established that filters that require periodic maintenance may not be well maintained in practice.", "Titanium dioxide, along with other materials, is a well known catalyst, and has used been along with a reducing agent, to reduce nitrogen oxides in flue gas (Vogel et al.", "U.S. Pat. No. 5,225,390).", "It has also been used as a basis for catalysts that oxidize carbon monoxide and various hydrocarbons (Vorob'iev U.S. Pat. No. 5,204,309).", "However, to accomplish this, gas temperatures must be higher than 100 degrees C. A typical temperature range is 100 degrees C. to 300 degrees C. It is known in the art of liquid filtering that titanium dioxide possesses the property of photo-catalytic activity.", "Here, the titanium dioxide becomes excited by ultraviolet light to act as a very effective catalyst to oxidize hydrocarbons, in solution.", "A disc of borosilicate glass can be coated with anatase titanium dioxide.", "Such a reactor can be spun at high RPM in the presence of ultraviolet light while liquids containing photocatalytically degradable organic material are applied to the disk (Urwin et al.", "U.S. Pat. No. 5,308,458).", "Dry titanium dioxide has been used to convert ethane to carbon dioxide and water (Daroux et al.", "Canadian J. of Chem.", "Eng.", "vol 63, Aug. 85).", "What is badly needed in the field of indoor air quality and HVAC is a low priced passive filter for carbon monoxide in air that works at room temperature and does not become contaminated so as to require periodic replacement or maintenance.", "This filter should function in a dry state and not require moving parts.", "It should remove most of the carbon monoxide normally present in breathable air as this air is passed through it at a reasonable flow rate.", "In addition, the filter should be simple to manufacture.", "SUMMARY OF THE INVENTION A tube, bulb, flat tile, or other reaction chamber is filled with a fine fibrous material such as fiberglass that has been coated with titanium dioxide.", "Embedded in the mesh of fibrous material is a source of ultraviolet light that excites the titanium dioxide into a photocatalytic state.", "Incident photons create electron-hole pairs in the titanium dioxide forming an active surface that has an affinity for oxygen molecules.", "When a CO molecule attaches to the titanium oxide-oxygen radical, the entire complex oxidizes the CO to carbon dioxide, a stable compound which is then released.", "Thus incoming carbon monoxide is effectively oxidized to carbon dioxide.", "There is no poisoning or degradation of the titanium dioxide in the filter by this process.", "Since carbon dioxide in low concentrations in breathable air is not objectionable, the filter converts a poisonous, very undesirable gas, to a stable, not undesirable one.", "One embodiment of the present invention is to form filter plates several feet square of the fibrous filter material.", "Each plate can contain a UV source, or the light can be piped into the material with lossy fiber optics (light fibers that loose light through their outer walls).", "The lossy light fibers themselves can be coated with titanium dioxide which becomes photocatalytic anytime UV light is in the fiber.", "Such lossy fibers can be formed into flat plates or placed in a bulb or chamber.", "The fiber ends can be terminated in a UV reflector to cause light reaching the fiber end to travel backward down the fiber and more efficiently defuse into the titanium dioxide.", "Such filters can be placed into the airflow of a building HVAC system to effectively remove CO from the circulating air supply of a building.", "These filters also have uses for filtering carbon monoxide from flow gases in pipes.", "BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of this invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention.", "FIG. 1 is a schematic diagram showing a bulb or reaction chamber filled with titanium dioxide and illuminated with an internal ultraviolet light source.", "FIG. 2 shows a conceptual design for a possible reaction chamber.", "FIG. 3 is a diagram showing the essential steps of the dry titanium dioxide photocatalytic chemistry as carbon monoxide is converted to carbon dioxide.", "FIG. 4 shows a flat plate filter suitable for HVAC systems.", "FIG. 5 shows another flat plate filter suitable for use in HVAC systems.", "It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.", "DESCRIPTION OF PREFERRED EMBODIMENTS The carbon monoxide filter is shown schematically in FIG. 1. Here a reaction chamber 1 forming a closed area is filled with a web or matrix of inert material 3.", "This inert material must be such that it can hold titanium dioxide and in addition not react with incoming air.", "Its most important property is that it provide mechanical support for the powered titanium dioxide.", "An addition, it should not be oxidized by the passage of moisture.", "Also, since the titanium dioxide is excited by light photons, this material should not compete for photons.", "A simple fibrous material such as fiber glass make by Owens Corning is quite sufficient.", "However, the invention is not limited to the use of fiberglass;", "any fibrous material capable of holding powdered titanium dioxide, either with and adhesive, or without, is acceptable and may be incorporated into the present invention.", "The web or fibrous material 3 is coated with anatase titanium dioxide that is applied in the form of a fine powder.", "The particle size can vary over a wide range.", "The important feature of the titanium dioxide is that there be sufficient surface area to absorb photons and interact with the carbon monoxide present in air.", "High dispersion pigment grade anatase titanium dioxide having a specific surface area of from about 10 to 50 square meters per gram is entirely adequate.", "This material is provided commercially as type AO-1 by Chimex Technology Co. of Uzbekistan and other companies.", "Titanium dioxide in rutile form having a surface area of less than 10 square meters per gram does not have enough surface area for use in the present invention.", "It is possible to use anatase material as fine as 200 square meters per gram.", "In general, the more surface area, the better.", "The titanium dioxide must be made to adhere to the fibrous matrix.", "In a dense matrix, the powder may simply be sprayed in.", "However, this technique may not totally coat the fibers with the density desired.", "A better method is to immerse the matrix in a low viscosity adhesive liquid so that most fiber surfaces wet.", "Then the powdered titanium dioxide will adhere to the fibers.", "As the adhesive sets, the titanium dioxide becomes glued to the surface of the fibers.", "The initial bath must not form globs that plug the matrix.", "It is possible to blow excess adhesive from the matrix with compressed air before blowing in titanium dioxide powder.", "Any method that deposits a high surface area of titanium dioxide into the matrix satisfies the present invention.", "An ultraviolet optical source 2 is mounted in the chamber.", "This source supplies photons to excite the titanium dioxide in the mesh 3 to a photocatalytic state as explained in the next section.", "This optical source 2 should supply a wavelength shorter than 360 nm since this wavelength represents the cutoff energy for semiconductor bandgap excitation in titanium dioxide.", "A mercury lamp such as a Hanovia 450 Watt lamp is sufficient but may require more power than is necessary since it is only necessary to supply enough photons to excite most of the surface area of the titanium dioxide.", "It is entirely possible to use lower power low-pressure UV lamps in the present invention.", "To fully excite the titanium dioxide, it is desirable to achieve a photon flux of between 0.5-1.3 times 10 to the 15 photons per square cm per second.", "However, the present invention will work satisfactorily at lower intensities.", "Air containing carbon monoxide enters the reaction chamber through an orifice 4;", "the CO reacts with the titanium dioxide, and air containing the resulting carbon dioxide exits from a second orifice 5.", "The maximum flow rate depends of such factors as the total surface area of the titanium dioxide, the concentration of CO in the incoming air, the degree of conversion required, and the intensity of the UV optical source.", "An alternative embodiment of the present invention suitable for an HVAC duct can be made from a frame containing the fibrous material (see FIG. 4).", "FIG. 2 shows a reaction chamber for removing carbon monoxide from air that is piped.", "Incoming air enter a first orifice 4, interacts with a matrix containing titanium dioxide 3 and exits from a second orifice 5.", "An ultraviolet light source 2 is embedded in the matrix to supply photons to the titanium dioxide.", "The UV light source 2 is powered by wires 6A and 6B from its electrodes 7A and 7B.", "These wires 6 run to external electrodes 8A and 8B from where they are attached to a power supply.", "FIG. 3 shows schematically the titanium dioxide surface photochemistry involved in oxidation of carbon monoxide to carbon dioxide.", "The outer electron orbitals of pure titanium contain two 3d electrons and two 4s electrons.", "In the oxide these four electrons from partially covalent and partially ionic bonds with two oxygen atoms.", "The two 3d electrons are no longer in the 3d band of the titanium atom, but in the 2p band of the extra oxygen.", "This bonding is ionic.", "Since the 3d band of pure titanium dioxide is empty, the pure oxide is an insulator.", "Slight impurities create holes in the oxygen 2p band and conduction electrons in the titanium 3d band to make the slightly impure material an extrinsic semiconductor.", "The material normally appears as an n type semiconductor since the typical impurities lead to an excess of conduction electrons.", "Excitation of this band structure by a photon of sufficient energy creates extra holes and electrons in pairs as an electron from the valance band is excited to the conduction band.", "The bandgap energy is approximately 3.45 electron volts.", "Thus the wavelength of the exciting UV light must be shorter than 360 nm.", "In FIG. 3, titanium dioxide 9 is excited by photons of sufficient energy 10 producing extra hole and electron pairs 11.", "In the presence of an electrophilic compound such as oxygen gas molecules, the solid surface is covered by negative adsorbed molecules.", "Therefore, the photo-produced hole is attracted to the surface by the electric field thus created.", "Under these conditions, the semiconductor becomes capable of separating the photo-produced charges and can behave as a photo-catalyst.", "Maintenance of electrical neutrality is achieved either by direct charge recombination or by an equilibrium between the holes reacting with an oxidizable negative species and electrons captured by a reducible species.", "Thus in FIG. 3, oxygen molecules 12 are attracted to the surface of the excited titanium dioxide 13.", "Conduction electrons convert O2 molecules to adsorbed O2 radicals.", "Holes convert the adsorbed molecules to single adsorbed O atoms at the surface.", "Carbon monoxide 14 attaches briefly to this complex 15\\16.", "The adsorbed oxygen atom reacts immediately to form carbon dioxide 17, and the titanium dioxide 18 remains unchanged from its initial state 18.", "The reaction continues in equilibrium at the surface of the titanium dioxide as long as there are enough photons to keep the catalyst excited, and enough carbon monoxide to convert to carbon dioxide.", "In the absence of carbon monoxide or other compounds to convert, and the in the continued presence of sufficient photons, the excited titanium dioxide-oxygen complex 13 is relatively stable.", "FIG. 4 shows a filter suitable for use in a duct associated with an HVAC system.", "A frame 19 of some suitable support material such as wood holds a matrix of fibers 3 that are coated with titanium dioxide.", "The filter is divided into tiles, and each tile contains an ultraviolet light source 2 to photo-excite the titanium dioxide in that tile.", "The fibrous material, which can be fiberglass or similar material, is from 0.5 to several inches thick.", "Normal HVAC flow rates through such tiles significantly reduce the amount of carbon monoxide in building air.", "The filter does not poison or degrade with time.", "However, air entering the filter should be prefiltered to first remove particulate matter that might lodge in the carbon monoxide filter.", "An alternative method of supplying UV light to the filter matrix is to use lossy optical waveguides.", "Here UV light of sufficient intensity and energy is launched into the fiber as with any other light fiber;", "however, the fiber is constructed with a particularly thin cladding that allows light to leak.", "Also there is very little difference (if any) in refractive index between the core and the cladding.", "Multimode plastic fibers that pass ultraviolet are particularly suitable for this application.", "The end of such a fiber should preferably contain a reflector so that there is no light loss from the fiber end;", "rather, the light diffuses out along the fiber in a uniform fashion.", "It is also possible to attach the titanium dioxide directly to these fibers providing the outer or reacting surface of the catalyst is exposed to enough light to become photo-excited.", "FIG. 5 shows another flat plate filter suitable for use in an air duct in a HVAC system.", "Fibrous material coated with titanium dioxide 3 is placed in a flat frame several inches thick.", "The fibrous material may be fiber glass or any other fiber web capable of holding titanium dioxide powder.", "A particularly attractive material is zeolite which is a chemical matrix capable of holding other compounds in its structure.", "The zeolite or zeolite membrane is pretreated with titanium dioxide before it is placed in the matrix 3.", "A UV light source 2 illuminates and photo-excites the titanium dioxide 3.", "Behind the UV light source 2 is an optional reflector 21 that causes most of the light from the source to impinge upon the titanium dioxide 3.", "Upstream of the titanium dioxide matrix 3 is an optional layer of volatile organic compound (VOC) capture medium.", "This optional layer 20 allows the filter to also remove VOC contaminants from the air along with carbon monoxide.", "This captive 20 medium, since it is "sticky", can be used to hold some or all of the titanium dioxide to increase carbon monoxide removal if desired.", "If titanium dioxide is used on such a sticky layer, means must be provided to illuminate it so it becomes photoexcited.", "The filtering medium holding the titanium dioxide may take the form of fibers, pellets, or coated surfaces of all types." ]
PRIORITY CLAIM The present application is a Continuation Application of pending U.S. patent application Ser. No. 12/521,842 filed on Jun. 30, 2009; which is a 371 application of PCT Application Serial No. PCT/US2008/055226 filed on Feb. 28, 2008; which claims the benefit of the U.S. Provisional Patent Application Ser. No. 60/903,823 filed on Feb. 28, 2007. The disclosures of the above applications/patents are incorporated herein by reference FIELD OF THE INVENTION The present invention relates generally to orthopedics, in particular, to a crimp used to hold surgical cable after it has been looped around a fractured bone. BACKGROUND OF THE INVENTION It is well known to use surgical cable and crimp assemblies to fix parts of a fractured bone and to join them together until the bone heals. Surgical procedures on and in the vicinity of a bone with closely neighboring nerves, arteries, muscle, ligaments, complicated anatomical structures and delicate areas represent a difficult and time consuming task for the surgeon. Thus it is important for the cable and crimp device to be assembled accurately, minimizing stress, trauma, risk, and injury to a patient while facilitating and shortening the procedure. Furthermore it is desirable to maintain the bulk of the cable as well as the joint where the cable is affixed to itself as compact as possible to minimize discomfort and damage to the surrounding tissue. Known minimally invasive techniques for such procedures generally involve looping the cable, isolated from the crimp member, about the bone and then inserting a beaded first end of the cable into a cavity of a groove in the crimp member. The groove at the crimp member allows the first end of the cable to slide in place until the bead locks in its final position. The second end of the cable is then inserted through the hole of the crimp member and the cable is tensioned by application of a tensioning tool to the cable through a handle, to a proximal abutment face of the crimp. Once the desired final tension has been established, the set screw is tightened using a screwdriver through the handle, deforming the cable inside the hole. The tensioning tool is then removed and the free end of the cable extending from the proximal abutment face of the crimp is cut off. Many of the known tools for performing this procedure require pulling the cable from both ends after the cable has been looped around the bone. To access both ends of the cable as required, such devices require significant spreading of the incision and the tissue along the path of the cable increasing trauma to muscle and other surrounding tissue and making them unsuitable for use in restricted areas. Such devices are disclosed, for example, in U.S. Pat. Nos. 5,649,927 and 6,017,347. Other devices such as that described in allow tensioning of the cable by application of a tensioning tool to one of the cable ends and to an abutment face of the crimp by employing a surgical cable factory crimped to one of the holes of the crimp, as those disclosed in U.S. Pat. Nos. 5,423,820, 6,007,268 and 6,387,099. The same effect is achieved by instruments such as that described in U.S. Pat. No. 6,017,347, that use a wire with a beaded end which locks into an end of the crimp preventing the wire from slipping out of the clamp. The bead locks into the end of the crimp preventing the wire from sliding out of the crimp. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a compact tool which is easy to assemble and use to secure surgical cable around bone without requiring a large incision and which minimizes the exposure or stripping of musculature away from the bone. Furthermore, it is an object of the present invention to provide a cable and crimp assembly that enables the cable to be inserted isolated from the crimp member, and the crimp member to be attached to the surgical cable only after the cable has been looped around the bone. The embodiments of the present invention comprise a flexible cable, a crimp member, a set screw, a handle, and a screw-driver. The surgical cable has an enlargement (e.g., a bead) affixed to its first end and the crimp member has a two-part groove, a cable hole for the cable and an oblique threaded hole for a set screw. The groove has a first part including a cavity sized to accept the beaded end of cable. The second part of groove is sized to allow the flexible cable to pass therethrough while stopping the larger, beaded first end of the cable. The cable hole is sized to accommodate the cable while the oblique threaded hole extends to the cable with an abutment, proximal face of the crimp member located near a proximal end of the cable hole. The present invention is also directed to a device for binding a cable about a fractured bone to stabilize a fracture comprising a slot including a distal opening sized to receive an enlarged end of a cable and a proximal opening sized to permit the cable to slide therethrough while preventing the enlarged end from passing therethough and a bore sized to slidably receive the cable, the bore extending to a proximal opening in combination with a locking element channel extending to a distal end opening into the bore and a locking element movable into a locking position in which a distal end of the locking element extends into the bore to engage a portion of the cable received therein and lock the cable in a desired position within the bore. Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Preferred features of the present invention are disclosed in the accompanying drawings, wherein similar reference characters denote similar elements throughout the several views, and wherein: FIG. 1 shows a side view of a crimp device according to the first embodiment of the present invention, prior to assembling with a flexible cable; FIG. 2 shows a top view of the crimp device of FIG. 1 ; FIG. 3 shows a proximal view of the crimp device of FIG. 1 ; FIG. 4 shows a perspective view of the crimp device of FIG. 1 ; FIG. 5 shows a side view of a disassembled system for fixing a cable about a fractured bone including the crimp device of FIG. 1 ; FIG. 6 shows a top view of the system of FIG. 5 ; FIG. 7 shows a first perspective view of the system of FIG. 5 ; FIG. 8 shows a second perspective view of the system of FIG. 5 ; FIG. 9 shows a side view of a set screw for use with a crimp device according to the invention; FIG. 10 shows a proximal view of the set screw of FIG. 9 ; FIG. 11 shows a perspective view of the set screw of FIG. 9 ; FIG. 12 shows a proximal view of a crimp device according a second embodiment of the present invention, prior to assembling with a flexible cable; FIG. 13 shows a top view of the crimp device of FIG. 12 ; FIG. 14 shows a side view of the crimp device of FIG. 12 ; FIG. 15 shows a perspective view of the crimp device of FIG. 12 ; FIG. 16 shows a side view of a system for fixing a cable about a fractured bone including the crimp device of FIG. 12 in a partially assembled state; FIG. 17 shows a perspective view of the system of FIG. 16 in a partially assembled state; FIG. 18 shows a side view of the system of FIG. 16 in a fully assembled state; and FIG. 19 shows a perspective view of the system of FIG. 16 in a fully assembled state. DETAILED DESCRIPTION Hereinafter, an apparatus and method for securing surgical cable around a bone according to the preferred embodiment of the present invention will be explained with reference to FIGS. 1-6 . As would be understood by those skilled in the art, the term ‘proximal’ describes a direction approaching a user (e.g., a surgeon) along the item being described while the term ‘distal’ refers to a direction away from the user along the item being described. Thus, the distal end of a cable refers to an end of the cable furthest from an end extending, for example out of the body to a point accessible to a user, along the cable and not to a portion of the cable located physically furthest from the operator. As shown in FIGS. 1-4 a binding member 10 according to a first embodiment of the present invention includes an outer surface 12 , a bone facing surface 14 , a distal end 16 and an abutment surface 18 formed at a proximal end 20 thereof. A groove 22 is formed in the binding member 10 extending distally at an angle from a proximal opening 24 in the abutment surface 18 adjacent to the bone facing surface 14 to a distal end 26 . A bore 28 extends from a proximal opening 30 at the distal end 26 of the groove 22 to a distal opening 32 in the distal end 16 . The bore 28 is preferably formed as a simple through hole sized to accept a flexible cable 34 to be held by the binding member 10 . The groove 22 according to this embodiment is formed as a two-part slotted hole open at the outer surface 12 . The proximal opening 24 of the groove 22 is preferably sized so that the cable 34 may slidably pass therethrough while an enlarged first end 36 of the cable 34 is prevented from passing therethrough. The groove 22 may also include a lip 38 (shown in FIG. 2 as the space between the broken lines and the unbroken lines of the groove 22 ) extending substantially around the perimeter thereof sized to permit the cable 34 to pass slidably therethrough while preventing the enlarged first end 36 from passing through. The rest of the groove 22 (i.e., an interior passage thereof) is preferably sized to permit the cable 34 and the enlarged first end 36 to slide therethrough. In addition, the groove 22 includes an enlarged distal opening 40 at the distal end 26 sized to permit the enlarged first end 36 to be inserted into the groove 22 . The binding member 10 further comprises a locking element channel 42 extending at an angle from a proximal opening 44 to a distal opening 46 into the bore 28 . As would be understood by those skilled in the art, although the locking element channel 42 is described in conjunction with the disclosed embodiments as receiving a set screw, any number of alternate locking elements may be employed to lock the cable 34 at a desired position in the bore 28 (i.e., to maintain a desired tension thereon) as will be described in more detail below. For example, the locking element may include an interference fit plug, a tube that is crushed, etc. or any other suitable device. As can be seen in FIG. 4 , a proximal part of the channel 42 may include a thread 48 sized to mate with the thread 52 of a corresponding part of a set screw 50 as shown in FIGS. 9-11 . A proximal end of the set screw 50 preferably includes a structure (e.g., a hex recess 51 ) to mate with a known tightening device (not shown) such as a screw driver, hex wrench, etc. As shown in FIGS. 5-8 , an apparatus for implanting a binding device 10 includes a mating element 54 including a first channel 56 which, when the element is in a desired position, is aligned with the bore 28 and a second channel 58 including a distal portion 60 which, when in the desired position, is aligned with the channel 42 and a proximal portion 62 which, in this embodiment, extends proximally from a proximal end of the distal portion 60 angled back toward the channel 56 to reduce a profile of the mating element 54 . As would be understood by those skilled in the art, the angle between the proximal and distal portions 62 , 60 , respectively, should preferably be no more than 20° to avoid impeding the operation of the universal joint in a tightening tool to be inserted therethrough as will be described below. Furthermore, a maximum width of the element 54 is preferably no more than 8 mm to minimize trauma to surrounding tissue. The element 54 also includes an abutting surface 64 which, when the element 54 is in the desired position, contacts the abutment surface 18 . In use, the cable 34 is first passed around the portion(s) of fractured bone to be stabilized and the enlarged first end 36 is inserted into the groove 22 via the opening 40 . The cable 34 and the enlarged first end 36 are then drawn through the groove 22 until contact between the enlarged first end 36 and the lip 38 prevents the enlarged end 36 from moving further. The second end of the cable 34 is then inserted into the distal opening 32 and passed through the bore 28 out of the proximal opening 30 and into the groove 22 . The second end of the cable 34 is drawn out of the proximal opening 24 and the slack in the cable 34 is drawn out by pulling the cable 34 proximally out of the opening 24 . The second end of the cable 34 is then inserted into the channel 56 and passed therethrough to a known tensioning mechanism (not shown) as the mating element 54 is moved distally over the cable 34 until the abutting surface 64 contacts the abutment surface 18 . The tensioning mechanism is then operated as would be understood by those skilled in the art until a desired tension is placed on the cable 34 . A tightening device including a joint (e.g., a universal joint) allowing the tightening device to navigate the bend in the channel 58 is then inserted through the channel 58 to mate with the hex recess 51 . The set screw 50 is then screwed into the channel 42 until a distal end thereof extends into the bore 28 locking the cable 34 in position therein and maintaining the desired tension in the cable 34 . The second end of the cable 34 may then be released from the tensioning mechanism and the portion of the cable 34 extending proximally from the groove 22 may be cut off and withdrawn from the body. As shown in FIGS. 12-19 , a binding member 100 according to a second embodiment of the invention operates in a manner substantially similar to that of the binding member 10 described above. Similar to the binding member 10 , the binding member 100 includes an outer surface 112 , a bone facing surface 114 , a distal end 116 and an abutment surface 118 formed at a proximal end 120 thereof. A groove 122 is formed in the binding member 100 extending distally from a proximal opening 124 in the abutment surface 118 to a distal end 26 . However, in the binding member 100 , the bore 128 does not open into the groove 122 . Rather, the bore 128 extends from a proximal opening 130 in proximal end 120 to a distal opening 132 in the distal end 116 . The bore 128 is preferably formed as a simple through hole sized to accept a flexible cable 34 to be held by the binding member 100 . The proximal opening 124 of the groove 122 is sized so that a cable 134 may slidably pass therethrough while an enlarged first end 136 of the cable 134 is prevented from passing therethrough. The groove 122 also includes a lip 138 extending substantially around the perimeter thereof sized to permit the cable 134 to pass slidably therethrough while preventing the enlarged first end 136 from passing through. The rest of the groove 122 (i.e., an interior passage thereof) is preferably sized to permit the cable 134 and the enlarged first end 136 to slide therethrough. In addition, the groove 122 includes an enlarged distal opening 140 at a distal end 126 thereof sized to permit the enlarged first end 136 to be inserted into the groove 122 . As the bore 128 does not open into the groove 122 , the groove 122 does not need to be angled relative to the outer surface 112 and the bone facing surface 114 . Rather, the groove 122 may extend substantially parallel to these surfaces allowing the thickness of the binding member 100 to be reduced. The binding member 100 further comprises a locking element channel 142 extending at an angle from a proximal opening 144 to a distal opening 146 into the bore 128 . As described above in regard to the binding member 10 , although the channel 142 is shown as adapted to receive a set screw 50 as shown in FIGS. 9-11 , any number of alternate locking elements may be employed to lock the cable 134 at a desired position in the bore 128 (i.e., to maintain a desired tension thereon). A proximal end of the set screw 50 preferably includes a structure (e.g., a hex recess 51 ) to mate with a known tightening device (not shown) such as a screw driver, hex wrench, etc. As shown in FIGS. 16-19 , an apparatus for implanting a binding device 100 includes a mating element 154 including a first channel (not shown) which, when the element 154 is in a desired position, is aligned with the bore 128 and a second channel (not shown) which may include an angled proximal section to reduce the profile of the element 154 similar to the distal portion 60 of the element 54 described above. The distal portion of this second channel, when in the element 154 is in the desired position, is aligned with the channel 142 . The element 154 also includes an abutting surface 164 which, when the element 154 is in the desired position, contacts the abutment surface 118 . In use, the cable 134 separate from the binding member 100 is inserted around the bone to be cerclaged as would be understood by those skilled in the art and the enlarged first end 136 is inserted into the groove 122 via the opening 140 . The cable 134 and the enlarged first end 136 are then drawn through the groove 122 until contact between the enlarged first end 136 and the lip 138 prevents the enlarged end 136 from moving further. The second end of the cable 134 is then inserted into the distal opening 132 and passed through the bore 128 out of the proximal opening 130 . The slack in the cable 134 is drawn out by pulling the cable 134 proximally out of the opening 130 and the second end of the cable 134 is inserted into the channel 156 and passed therethrough to a known tensioning mechanism (not shown) as the mating element 154 is moved distally over the cable 134 until the abutting surface 164 contacts the abutment surface 118 . The tensioning mechanism is then operated as would be understood by those skilled in the art until a desired tension is placed on the cable 134 . As described above in regard to element 54 , a tightening device is inserted through the second channel to mate with the hex recess 51 . The set screw 50 is then screwed into the channel 142 until a distal end thereof extends into the bore 128 locking the cable 134 in position therein and maintaining the desired tension in the cable 134 . The second end of the cable 134 may then be released from the tensioning mechanism and the portion of the cable 34 extending proximally from the opening 130 may be cut off and withdrawn from the body. The present invention has been described with reference to specific exemplary embodiments. Those skilled in the art will understand that various modifications and changes may be made to the embodiments without departing from the teaching of the invention. These embodiments specification are therefore, to be regarded in an illustrative rather than a restrictive sense and are not intended to limit the scope of the invention which is intended to cover all modifications and variations of this invention that come within the scope of the appended claims and their equivalents.
A device for binding a cable about a fractured bone to stabilize a fracture includes a slot including a distal opening sized to receive an enlarged end of a cable and a proximal opening sized to permit the cable to slide therethrough while preventing the enlarged end from passing therethough and a bore sized to slidably receive the cable, the bore extending to a proximal opening in combination with a locking element channel extending to a distal end opening into the bore and a locking element movable into a locking position in which a distal end of the locking element extends into the bore to engage a portion of the cable received therein and lock the cable in a desired position within the bore.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "PRIORITY CLAIM The present application is a Continuation Application of pending U.S. patent application Ser.", "No. 12/521,842 filed on Jun. 30, 2009;", "which is a 371 application of PCT Application Serial No. PCT/US2008/055226 filed on Feb. 28, 2008;", "which claims the benefit of the U.S. Provisional Patent Application Ser.", "No. 60/903,823 filed on Feb. 28, 2007.", "The disclosures of the above applications/patents are incorporated herein by reference FIELD OF THE INVENTION The present invention relates generally to orthopedics, in particular, to a crimp used to hold surgical cable after it has been looped around a fractured bone.", "BACKGROUND OF THE INVENTION It is well known to use surgical cable and crimp assemblies to fix parts of a fractured bone and to join them together until the bone heals.", "Surgical procedures on and in the vicinity of a bone with closely neighboring nerves, arteries, muscle, ligaments, complicated anatomical structures and delicate areas represent a difficult and time consuming task for the surgeon.", "Thus it is important for the cable and crimp device to be assembled accurately, minimizing stress, trauma, risk, and injury to a patient while facilitating and shortening the procedure.", "Furthermore it is desirable to maintain the bulk of the cable as well as the joint where the cable is affixed to itself as compact as possible to minimize discomfort and damage to the surrounding tissue.", "Known minimally invasive techniques for such procedures generally involve looping the cable, isolated from the crimp member, about the bone and then inserting a beaded first end of the cable into a cavity of a groove in the crimp member.", "The groove at the crimp member allows the first end of the cable to slide in place until the bead locks in its final position.", "The second end of the cable is then inserted through the hole of the crimp member and the cable is tensioned by application of a tensioning tool to the cable through a handle, to a proximal abutment face of the crimp.", "Once the desired final tension has been established, the set screw is tightened using a screwdriver through the handle, deforming the cable inside the hole.", "The tensioning tool is then removed and the free end of the cable extending from the proximal abutment face of the crimp is cut off.", "Many of the known tools for performing this procedure require pulling the cable from both ends after the cable has been looped around the bone.", "To access both ends of the cable as required, such devices require significant spreading of the incision and the tissue along the path of the cable increasing trauma to muscle and other surrounding tissue and making them unsuitable for use in restricted areas.", "Such devices are disclosed, for example, in U.S. Pat. Nos. 5,649,927 and 6,017,347.", "Other devices such as that described in allow tensioning of the cable by application of a tensioning tool to one of the cable ends and to an abutment face of the crimp by employing a surgical cable factory crimped to one of the holes of the crimp, as those disclosed in U.S. Pat. Nos. 5,423,820, 6,007,268 and 6,387,099.", "The same effect is achieved by instruments such as that described in U.S. Pat. No. 6,017,347, that use a wire with a beaded end which locks into an end of the crimp preventing the wire from slipping out of the clamp.", "The bead locks into the end of the crimp preventing the wire from sliding out of the crimp.", "SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a compact tool which is easy to assemble and use to secure surgical cable around bone without requiring a large incision and which minimizes the exposure or stripping of musculature away from the bone.", "Furthermore, it is an object of the present invention to provide a cable and crimp assembly that enables the cable to be inserted isolated from the crimp member, and the crimp member to be attached to the surgical cable only after the cable has been looped around the bone.", "The embodiments of the present invention comprise a flexible cable, a crimp member, a set screw, a handle, and a screw-driver.", "The surgical cable has an enlargement (e.g., a bead) affixed to its first end and the crimp member has a two-part groove, a cable hole for the cable and an oblique threaded hole for a set screw.", "The groove has a first part including a cavity sized to accept the beaded end of cable.", "The second part of groove is sized to allow the flexible cable to pass therethrough while stopping the larger, beaded first end of the cable.", "The cable hole is sized to accommodate the cable while the oblique threaded hole extends to the cable with an abutment, proximal face of the crimp member located near a proximal end of the cable hole.", "The present invention is also directed to a device for binding a cable about a fractured bone to stabilize a fracture comprising a slot including a distal opening sized to receive an enlarged end of a cable and a proximal opening sized to permit the cable to slide therethrough while preventing the enlarged end from passing therethough and a bore sized to slidably receive the cable, the bore extending to a proximal opening in combination with a locking element channel extending to a distal end opening into the bore and a locking element movable into a locking position in which a distal end of the locking element extends into the bore to engage a portion of the cable received therein and lock the cable in a desired position within the bore.", "Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS Preferred features of the present invention are disclosed in the accompanying drawings, wherein similar reference characters denote similar elements throughout the several views, and wherein: FIG. 1 shows a side view of a crimp device according to the first embodiment of the present invention, prior to assembling with a flexible cable;", "FIG. 2 shows a top view of the crimp device of FIG. 1 ;", "FIG. 3 shows a proximal view of the crimp device of FIG. 1 ;", "FIG. 4 shows a perspective view of the crimp device of FIG. 1 ;", "FIG. 5 shows a side view of a disassembled system for fixing a cable about a fractured bone including the crimp device of FIG. 1 ;", "FIG. 6 shows a top view of the system of FIG. 5 ;", "FIG. 7 shows a first perspective view of the system of FIG. 5 ;", "FIG. 8 shows a second perspective view of the system of FIG. 5 ;", "FIG. 9 shows a side view of a set screw for use with a crimp device according to the invention;", "FIG. 10 shows a proximal view of the set screw of FIG. 9 ;", "FIG. 11 shows a perspective view of the set screw of FIG. 9 ;", "FIG. 12 shows a proximal view of a crimp device according a second embodiment of the present invention, prior to assembling with a flexible cable;", "FIG. 13 shows a top view of the crimp device of FIG. 12 ;", "FIG. 14 shows a side view of the crimp device of FIG. 12 ;", "FIG. 15 shows a perspective view of the crimp device of FIG. 12 ;", "FIG. 16 shows a side view of a system for fixing a cable about a fractured bone including the crimp device of FIG. 12 in a partially assembled state;", "FIG. 17 shows a perspective view of the system of FIG. 16 in a partially assembled state;", "FIG. 18 shows a side view of the system of FIG. 16 in a fully assembled state;", "and FIG. 19 shows a perspective view of the system of FIG. 16 in a fully assembled state.", "DETAILED DESCRIPTION Hereinafter, an apparatus and method for securing surgical cable around a bone according to the preferred embodiment of the present invention will be explained with reference to FIGS. 1-6 .", "As would be understood by those skilled in the art, the term ‘proximal’ describes a direction approaching a user (e.g., a surgeon) along the item being described while the term ‘distal’ refers to a direction away from the user along the item being described.", "Thus, the distal end of a cable refers to an end of the cable furthest from an end extending, for example out of the body to a point accessible to a user, along the cable and not to a portion of the cable located physically furthest from the operator.", "As shown in FIGS. 1-4 a binding member 10 according to a first embodiment of the present invention includes an outer surface 12 , a bone facing surface 14 , a distal end 16 and an abutment surface 18 formed at a proximal end 20 thereof.", "A groove 22 is formed in the binding member 10 extending distally at an angle from a proximal opening 24 in the abutment surface 18 adjacent to the bone facing surface 14 to a distal end 26 .", "A bore 28 extends from a proximal opening 30 at the distal end 26 of the groove 22 to a distal opening 32 in the distal end 16 .", "The bore 28 is preferably formed as a simple through hole sized to accept a flexible cable 34 to be held by the binding member 10 .", "The groove 22 according to this embodiment is formed as a two-part slotted hole open at the outer surface 12 .", "The proximal opening 24 of the groove 22 is preferably sized so that the cable 34 may slidably pass therethrough while an enlarged first end 36 of the cable 34 is prevented from passing therethrough.", "The groove 22 may also include a lip 38 (shown in FIG. 2 as the space between the broken lines and the unbroken lines of the groove 22 ) extending substantially around the perimeter thereof sized to permit the cable 34 to pass slidably therethrough while preventing the enlarged first end 36 from passing through.", "The rest of the groove 22 (i.e., an interior passage thereof) is preferably sized to permit the cable 34 and the enlarged first end 36 to slide therethrough.", "In addition, the groove 22 includes an enlarged distal opening 40 at the distal end 26 sized to permit the enlarged first end 36 to be inserted into the groove 22 .", "The binding member 10 further comprises a locking element channel 42 extending at an angle from a proximal opening 44 to a distal opening 46 into the bore 28 .", "As would be understood by those skilled in the art, although the locking element channel 42 is described in conjunction with the disclosed embodiments as receiving a set screw, any number of alternate locking elements may be employed to lock the cable 34 at a desired position in the bore 28 (i.e., to maintain a desired tension thereon) as will be described in more detail below.", "For example, the locking element may include an interference fit plug, a tube that is crushed, etc.", "or any other suitable device.", "As can be seen in FIG. 4 , a proximal part of the channel 42 may include a thread 48 sized to mate with the thread 52 of a corresponding part of a set screw 50 as shown in FIGS. 9-11 .", "A proximal end of the set screw 50 preferably includes a structure (e.g., a hex recess 51 ) to mate with a known tightening device (not shown) such as a screw driver, hex wrench, etc.", "As shown in FIGS. 5-8 , an apparatus for implanting a binding device 10 includes a mating element 54 including a first channel 56 which, when the element is in a desired position, is aligned with the bore 28 and a second channel 58 including a distal portion 60 which, when in the desired position, is aligned with the channel 42 and a proximal portion 62 which, in this embodiment, extends proximally from a proximal end of the distal portion 60 angled back toward the channel 56 to reduce a profile of the mating element 54 .", "As would be understood by those skilled in the art, the angle between the proximal and distal portions 62 , 60 , respectively, should preferably be no more than 20° to avoid impeding the operation of the universal joint in a tightening tool to be inserted therethrough as will be described below.", "Furthermore, a maximum width of the element 54 is preferably no more than 8 mm to minimize trauma to surrounding tissue.", "The element 54 also includes an abutting surface 64 which, when the element 54 is in the desired position, contacts the abutment surface 18 .", "In use, the cable 34 is first passed around the portion(s) of fractured bone to be stabilized and the enlarged first end 36 is inserted into the groove 22 via the opening 40 .", "The cable 34 and the enlarged first end 36 are then drawn through the groove 22 until contact between the enlarged first end 36 and the lip 38 prevents the enlarged end 36 from moving further.", "The second end of the cable 34 is then inserted into the distal opening 32 and passed through the bore 28 out of the proximal opening 30 and into the groove 22 .", "The second end of the cable 34 is drawn out of the proximal opening 24 and the slack in the cable 34 is drawn out by pulling the cable 34 proximally out of the opening 24 .", "The second end of the cable 34 is then inserted into the channel 56 and passed therethrough to a known tensioning mechanism (not shown) as the mating element 54 is moved distally over the cable 34 until the abutting surface 64 contacts the abutment surface 18 .", "The tensioning mechanism is then operated as would be understood by those skilled in the art until a desired tension is placed on the cable 34 .", "A tightening device including a joint (e.g., a universal joint) allowing the tightening device to navigate the bend in the channel 58 is then inserted through the channel 58 to mate with the hex recess 51 .", "The set screw 50 is then screwed into the channel 42 until a distal end thereof extends into the bore 28 locking the cable 34 in position therein and maintaining the desired tension in the cable 34 .", "The second end of the cable 34 may then be released from the tensioning mechanism and the portion of the cable 34 extending proximally from the groove 22 may be cut off and withdrawn from the body.", "As shown in FIGS. 12-19 , a binding member 100 according to a second embodiment of the invention operates in a manner substantially similar to that of the binding member 10 described above.", "Similar to the binding member 10 , the binding member 100 includes an outer surface 112 , a bone facing surface 114 , a distal end 116 and an abutment surface 118 formed at a proximal end 120 thereof.", "A groove 122 is formed in the binding member 100 extending distally from a proximal opening 124 in the abutment surface 118 to a distal end 26 .", "However, in the binding member 100 , the bore 128 does not open into the groove 122 .", "Rather, the bore 128 extends from a proximal opening 130 in proximal end 120 to a distal opening 132 in the distal end 116 .", "The bore 128 is preferably formed as a simple through hole sized to accept a flexible cable 34 to be held by the binding member 100 .", "The proximal opening 124 of the groove 122 is sized so that a cable 134 may slidably pass therethrough while an enlarged first end 136 of the cable 134 is prevented from passing therethrough.", "The groove 122 also includes a lip 138 extending substantially around the perimeter thereof sized to permit the cable 134 to pass slidably therethrough while preventing the enlarged first end 136 from passing through.", "The rest of the groove 122 (i.e., an interior passage thereof) is preferably sized to permit the cable 134 and the enlarged first end 136 to slide therethrough.", "In addition, the groove 122 includes an enlarged distal opening 140 at a distal end 126 thereof sized to permit the enlarged first end 136 to be inserted into the groove 122 .", "As the bore 128 does not open into the groove 122 , the groove 122 does not need to be angled relative to the outer surface 112 and the bone facing surface 114 .", "Rather, the groove 122 may extend substantially parallel to these surfaces allowing the thickness of the binding member 100 to be reduced.", "The binding member 100 further comprises a locking element channel 142 extending at an angle from a proximal opening 144 to a distal opening 146 into the bore 128 .", "As described above in regard to the binding member 10 , although the channel 142 is shown as adapted to receive a set screw 50 as shown in FIGS. 9-11 , any number of alternate locking elements may be employed to lock the cable 134 at a desired position in the bore 128 (i.e., to maintain a desired tension thereon).", "A proximal end of the set screw 50 preferably includes a structure (e.g., a hex recess 51 ) to mate with a known tightening device (not shown) such as a screw driver, hex wrench, etc.", "As shown in FIGS. 16-19 , an apparatus for implanting a binding device 100 includes a mating element 154 including a first channel (not shown) which, when the element 154 is in a desired position, is aligned with the bore 128 and a second channel (not shown) which may include an angled proximal section to reduce the profile of the element 154 similar to the distal portion 60 of the element 54 described above.", "The distal portion of this second channel, when in the element 154 is in the desired position, is aligned with the channel 142 .", "The element 154 also includes an abutting surface 164 which, when the element 154 is in the desired position, contacts the abutment surface 118 .", "In use, the cable 134 separate from the binding member 100 is inserted around the bone to be cerclaged as would be understood by those skilled in the art and the enlarged first end 136 is inserted into the groove 122 via the opening 140 .", "The cable 134 and the enlarged first end 136 are then drawn through the groove 122 until contact between the enlarged first end 136 and the lip 138 prevents the enlarged end 136 from moving further.", "The second end of the cable 134 is then inserted into the distal opening 132 and passed through the bore 128 out of the proximal opening 130 .", "The slack in the cable 134 is drawn out by pulling the cable 134 proximally out of the opening 130 and the second end of the cable 134 is inserted into the channel 156 and passed therethrough to a known tensioning mechanism (not shown) as the mating element 154 is moved distally over the cable 134 until the abutting surface 164 contacts the abutment surface 118 .", "The tensioning mechanism is then operated as would be understood by those skilled in the art until a desired tension is placed on the cable 134 .", "As described above in regard to element 54 , a tightening device is inserted through the second channel to mate with the hex recess 51 .", "The set screw 50 is then screwed into the channel 142 until a distal end thereof extends into the bore 128 locking the cable 134 in position therein and maintaining the desired tension in the cable 134 .", "The second end of the cable 134 may then be released from the tensioning mechanism and the portion of the cable 34 extending proximally from the opening 130 may be cut off and withdrawn from the body.", "The present invention has been described with reference to specific exemplary embodiments.", "Those skilled in the art will understand that various modifications and changes may be made to the embodiments without departing from the teaching of the invention.", "These embodiments specification are therefore, to be regarded in an illustrative rather than a restrictive sense and are not intended to limit the scope of the invention which is intended to cover all modifications and variations of this invention that come within the scope of the appended claims and their equivalents." ]
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The subject invention is generally related to sensor, monitor and control appliance devices generally utilized in monitoring and surveillance systems and is specifically directed to a network adaptation of such appliances. [0003] 2. Discussion of the Prior Art [0004] Security of public facilities such as schools, banks, airports, arenas and the like is a topic of increasing concern in recent years. Over the past few years, a number of violent incidents including bombings, shootings, arson, and hostage situations have occurred. In addition, agencies responsible for public security in these facilities must cope with more commonplace crimes, such as drug dealing, vandalism, theft and the like. [0005] Such facilities frequently employ monitoring and surveillance systems and access control systems to enhance security. This has been common practice for a number of years. Such systems generally have a centralized monitoring console, usually attended by a guard or dispatcher. A variety of sensors are located throughout the facility, such as smoke detectors, fire detectors, motion sensors, glass breakage detectors, badge readers at various access points, and sometimes, video cameras and/or microphones. Other sensors and transducers are utilized to lock and unlock doors. [0006] There are numerous devices utilized to collect information at remote locations and initiate a local alarm, store the information for later retrieval or forward the information to a remote location for storage and/or near real time review. Examples include fire alarms, security cameras, motion sensors, proximity switches, heat sensors, smoke and fire sensors, and the like. Almost all of these appliances can be used in some form of configuration where one or more sensors may be used in combination to provide a surveillance scheme over an area to be monitored. In prior art systems, the signal generated by each type of device was used locally, or if part of a network, was sent over a dedicated connection to a remote collection point for that type of device. [0007] These prior-art devices often use technologies that not ‘intelligent’ in the modern sense; they merely provide an ‘ON/OFF’ indication to the centralized monitoring system. The appliances also are not ‘networked’ in the modern sense; they are generally hard-wired to the centralized monitoring system via a ‘current loop’ or similar arrangement, and do not provide situational data other than their ON/OFF status. SUMMARY OF THE INVENTION [0008] The subject invention is directed to support function systems that may be used separately or in combination as building support devices by adapting them to network appliances and configuring them to communicate over network topologies to each other, to building databases, and to the users. This allows either stand alone functional systems, or a fully integrating them into a single “seamless” system. By way of example, school classrooms may have several communications and monitoring systems to support a classroom such as an intercom, clock system, thermostat, motion detector, door access control, computer network connections and the like. The subject invention permits the combination of all of these functions into a single device that may communicate over a single network connection providing various combinations to provide for building support functions. The devices may also communicate to other buildings and control nodes in other facilities by use of Wide Area Networks (WANs) such as Intranets and the Internet. [0009] The invention is particularly well adapted for use in connection with my co-pending patent applications, entitled: Multimedia Surveillance and Monitoring System Including Network Configuration, Ser. No. 09/594,041, filed on Jun. 14, 2000; Method and Apparatus for Distributing Digitized Streaming Video Over a Network, Ser. No. 09/716,141, filed on Nov. 17, 2000; and Method and Apparatus for Collecting, Sending, Archiving and Retrieving Motion Video and Still Images and Notification of Detected Events, Ser. No. 09/853,274, filed May 11, 2001, and incorporated by reference herein. [0010] The subject invention includes specific network appliances designed to participate in a comprehensive multimedia security and building support system that may be deployed singularly or in combination to achieve the degree of monitoring and protection desired. [0011] The subject invention also permits all of the support functions to be combined in one appliance, achieving both improved functionality and support at a lower costs because of use of shared components, shared wiring and shared network connectivity. In the preferred embodiment, the appliance is connected to a single Category5 (CAT5) wire, fiber or the like to the system network. The single appliance provides all of the functions previously supplied by a plurality of dedicated purpose discrete appliances. [0012] Functional superiority over the discrete appliances is also achieved because of the opportunity to integrate the various subsystems common in the appliances. For example, a universal wall appliance in accordance with the subject invention can use a common display panel for a clock/bell system and a visual alarm. A single microphone can be shared for the intercom, for noise detection and for alarm oral response or activation. A single speaker can be utilized for the intercom, a telephone call bell, an alarm emitter and a clock/bell sound emitter. A single temperature sensor can be shared between a fire alarm system, the HVAC system and be utilized to check for appliances proper ambient operating temperature environment. A wireless LAN access point can be shared for remote or mobile alarm/sensor/display modules and for classroom computer access. A single video camera can be shared for security monitoring, video conferencing and distance learning. A single streaming audio/video decoder can present Video On Demand (VOD) classroom video presentations, broadcast television and video conferencing. [0013] The subject invention permits network components and appliances to be used in combination with a network based full service, multi-media surveillance system capable of a wide range of monitoring techniques utilizing digital network architecture. [0014] Schools, banks, retail operations and other security conscious businesses and institutions have a need for advanced hardware and software solutions that provide total, user friendly control over their surveillance and monitoring equipment. A system desirably provides: [0015] 1. Multimedia data collection; [0016] 2. Automated control; [0017] 3. Archive storage; [0018] 4. Enhanced search and recall of archived event recordings; [0019] 5. Preset responses to triggers and triggering events; [0020] 6. Remote viewing and management from a wide area network including, preferably, the World Wide Web (or Internet) accessibility. [0021] 7. Automatic system pre-failure prediction and post failure analysis. [0022] 8. Common infrastructure and workstations shared with other co-located systems. [0023] 9. Wireless infrastructure for sensors, monitors and shared applications/systems. [0024] In accordance with the teachings of the subject invention, any or a plurality of distinctive appliances may be connected to the comprehensive, wired/wireless multimedia surveillance and monitoring system for transmitting event data, video and/or image monitoring information, audio signals and other network appliance sensor and detector data over significant distances using digital data transmission over networks such as a local area network (LAN), a wireless LAN (WLAN), a wide area network (WAN) such as the Internet for other network automatic event recording, assessment and response, including dispatch of response personnel. Wired, wireless and optical appliances and sensor systems may be employed. The wireless LAN connectivity permits local distribution of sensor, audio, video and image data with relatively high bandwidth without expensive local wiring/fiber and without the requirement of a license and without relying on a common carrier and the fees associated therewith. The surveillance system may be interfaced with a WAN (wide area network) such as optical fiber, frame relay or the Internet for providing a worldwide, low cost surveillance system with virtually unlimited geographic application. Centralized and distributed remote monitoring stations have access to all of the surveillance data from various remote locations via the network or the WAN. A server provides a centralized location for data collection, alarm detection and processing, access control, auto response generation, paging, automatic e-mail generation, telephone dialing and message transmission, dispatch processing, logging functions, configuration management, and/or other specialized functions. The server may be inserted virtually anywhere in the Intranet/Internet network, and may be segmented and installed in a distributed manner to further add to system security, reduce bandwidth requirements, or allow redundancy. [0025] Multiple sensors and appliances may be accommodated, as required. The topology of the network will be established by the geographic situation of the specific installation. Appropriate firewalls, encryption and access codes may be set up as desired to protect unauthorized access to the system or collected data. The server based system permits a security provider to have access to the appliance, related sensor and surveillance data or to configure or reconfigure the system from any station on the Intranet or Internet. [0026] The system of the subject invention permits comprehensive monitoring of locations over great distances with sufficient performance to provide widespread use as a security surveillance device. [0027] The subject invention is specifically directed to networked appliances such as video and/or image appliances, access control devices, detectors and sensors as well as audio, condition and/or event monitoring systems. In its preferred form, the comprehensive multimedia safety and surveillance system of the subject invention provides both visual and audio information as well as critical data such as temperature fire and smoke detection. Manually operated transducers, such as panic buttons, door contacts, floor sensors, and the like may also be included to activate the system in the presence of an event at the sensor location, such as a fire alarm or security alarm panic bar or the like. Controlled transducers, such as electric door strikes, magnetic door strikes, electric door openers, strobe lights, sirens, room lights, fire control equipment and the like can be controlled by the appliances. Numerous appliances, including but not limited to detection and sensor systems, are utilized to provide monitoring stations or personnel, such as security personnel, and/or a base station monitoring critical information from the sensor system and to record the information and permit reconstruction of events after the fact. [0028] In its preferred form, a plurality of sensor units, which may include at least one video image appliance sensor and/or at least one audio appliance sensor and/or at least one motion appliance sensor and/or other sensors, are placed strategically about the facility to be monitored. In addition, strategically placed motion detectors, fire sensors, panic switches, smoke sensors and other monitoring equipment is incorporated in the system. Cameras may be placed throughout the facility and in other desired spaces including on the grounds outside the facility. The audio sensors/transducers and other sensors and detectors are also strategically located both internal and external of the facility. [0029] While the appliances of the subject system may be hardwired, in its preferred form the system of the present invention is adapted for use in connection with wireless transmission and receiving systems. The wireless system is particularly useful for adapting the system as a retrofit in existing facilities and also provides assurances against disruption of data transmission such as during a fire, as well as permitting roving interactive monitors that can be carried or worn. In the preferred embodiment, the wireless system is fully self-contained with each appliance and/or sensor unit having an independent power supply and, where required for image sensors, a sensor light source. The security system may include either motion sensitive, audio sensitive and/or image processing based activation systems so that the equipment is not activated until some event is detected, i.e., the system is action triggered. [0030] In the preferred embodiment, each appliance will transmit any detected information to a monitor system located at a base monitoring station, located on site and/or at a remote or roving location, and/or a server for logging, forwarding, archiving same. The base station has instant live access to all of the image and audio signals as they are captured by the sensors, and where desired is adapted to record and make an historic record of the images for archive purposes. Where random access recording techniques are used, such as, by way of example, digital random access memory storage devices or high speed disk storage arrays, the archive may be readily searched for stored information. [0031] One significant advantage to the appliance configuration of the subject invention is that it permits multimedia surveillance in applications and locations where physical wiring cannot be used, and over distances not possible or not cost effective with other systems. The system of the present invention provides surveillance capability utilizing techniques ranging from closed-circuit, hard wired systems to the Internet based techniques and is not limited by the data capacity; or cost associated with systems currently on the market. [0032] It is, therefore, an object and feature of the subject invention to provide both wired and wireless communication links between appliances, sensors, monitors and/or sensors. [0033] It is an additional object and feature of the subject invention to provide an appliance configuration for a multimedia surveillance system adapted for any of a plurality of monitoring and surveillance appliances which may be incorporated in the system via network connections through a server to provide a versatile, wide-ranging multi-media system which may be configured to meet specific application needs. [0034] It is an additional object and feature of the subject invention to provide an appliance and monitoring station configuration for a multimedia surveillance system adapted for a plurality simultaneously operating geographically distributed monitoring stations. [0035] It is another object and feature of the subject invention to provide appliances adapted for use in connection with a surveillance system for transmitting data over significant distances using typical bandwidth carriers such as the public telephone system, and wireless carriers such as cellular telephones, including AMPS, PCS, GSM, CDMA, wide band CDMA and the like, CDPD data links, two-way pagers, satellite networks such as Iridium and the like. [0036] It is another object and feature of the subject invention to provide appliances adapted for use in connection with a surveillance system for transmitting data over significant distances using typical broadband carriers such as cable TV networks, dedicated fiber optics networks, DSL and ADSL carriers, and forthcoming broadband wireless networks. [0037] It is also an object and feature of the subject invention to provide appliances for a surveillance system adapted for utilizing wired video and/or image data collection and/or transmission using the Internet and/or IP protocols. [0038] It is also an object and feature of the subject invention to provide appliances for a surveillance system adapted for utilizing wireless video and/or image data collection and/or transmission using the Internet and/or IP protocols. [0039] It is also an object and feature of the subject invention to utilize network communication systems to distribute both appliance surveillance data and control data. [0040] It is another object and feature of the subject invention to provide network appliances for a security surveillance system adapted for use in connection with a wireless LAN (WLAN) communications system, such as the IEEE 802.11 standards and follow-on standards. [0041] It is another object and feature of the subject invention to provide time display to a network appliance communicating over the IP network. [0042] It is another object and feature of the subject invention to provide emergency event annunciation to a network appliance communicating over the IP network. [0043] It is another object and feature of the subject invention to provide room paging through a network appliance communicating over the IP network. [0044] It is another object and feature of the subject invention to provide room audio monitoring utilizing a network appliance communicating over the IP network. [0045] It is another object and feature of the subject invention to provide room intercom utilizing a network appliance communicating over the IP network. [0046] It is another object and feature of the subject invention to provide room temperature sensing using a network appliance communicating over the IP network. [0047] It is another object and feature of the subject invention to provide device temperature sensing using a network appliance communicating over the IP network. [0048] It is another object and feature of the subject invention to provide room gunshot detection utilizing a network appliance communicating over the IP network. [0049] It is another object and feature of the subject invention to provide room access control utilizing a network appliance communicating over the IP network. [0050] It is another object and feature of the subject invention to provide an audio monitor or intercom between one or more network appliances and one or more monitor system using voice-over-IP (VOIP). [0051] It is another object and feature of the subject invention to provide an audio monitor or intercom between two or more network appliances utilizing VOIP. [0052] It is another object and feature of the subject invention to provide archival storage of VOIP audio information for later playback. [0053] It is another object and feature of the subject invention to provide a network appliance with video and/or audio capability with muted camera video and/or muted microphone audio capability in a room for privacy. [0054] It is another object and feature of the subject invention to provide a network appliance device that has an open camera and/or microphone when panic button is pushed. [0055] It is another object and feature of the subject invention to provide “intercom” and “emergency” buttons on a panic button. [0056] It is another object and feature of the subject invention to provide panic button initiated actions, such as: [0057] Intercom functions to and from room over IP. [0058] Logging of all intercom calls. [0059] Emergency notification to wired guard stations over IP. [0060] Emergency notification to wireless guard stations over IP. [0061] Push-To-Talk (or voice activation) response from guard or administrator. [0062] Display on room display stating identity of the responding party. [0063] Flashing location icon on map for intercom or emergency. [0064] Pop-up name of person pushing panic button. [0065] Pop-up location of person pushing panic button. [0066] Pop-up name of room where emergency is taking place. [0067] Logging of all panic button pushes, by whom, time, location, and the like. [0068] Logging of all responses, by whom, time, and the like. [0069] Recording of all emergency audio/video on server or appliance. [0070] For emergency calls, automatic call list: i.e., if first guard does not respond, go to next, go to administration. [0071] For emergency calls, have a party line: i.e., call all stations, all can respond asynchronously. [0072] On party line, all stations display the name of any speaker doing a push-to-talk (or voice activation) operation, with workstations having a pop-up display and wall appliance display shows instead of time. [0073] A software priority is established for the responding push to talk (or voice activation). Automatic notification priority based upon location, nearest, first, and so on. [0074] It is another object and feature of the subject invention to provide a workstation-to-workstation intercom utilizing VOIP. [0075] It is another object and feature of the subject invention to provide push-to-talk or voice activated control of audio from two or more stations on a group session at one time. [0076] It is another object and feature of the subject invention to provide an audio/video intercom from workstation-to-workstation utilizing VOIP. [0077] It is another object and feature of the subject invention to provide map-based dialing to workstations or network appliances. [0078] It is another object and feature of the subject invention to provide menu-based dialing to workstations or network appliances. [0079] It is another object and feature of the subject invention to provide IP video to and from network appliances. [0080] It is another object and feature of the subject invention to provide logging of all calls. [0081] It is another object and feature of the subject invention to provide logging of all calls with caller and/or called station ID's. [0082] It is another object and feature of the subject invention to provide logging of all calls with time stamps for time of calling and answering. [0083] It is another object and feature of the subject invention to provide logging of all calls by recording actual audio on the server. [0084] It is another object and feature of the subject invention to provide calls to guard stations and standard PC workstations. [0085] It is another object and feature of the subject invention to provide calls to administrative stations. [0086] It is another object and feature of the subject invention to provide calls from any workstation to any other workstation. [0087] It is another object and feature of the subject invention to provide other voice interfaces, such as: [0088] Calls patched into POTS telephone calls from the “outside” through a gateway network appliance device. [0089] Calls on internal PBX through a gateway network appliance device. [0090] Multimedia network appliances can be patched into VOIP telephone calls such as from the Internet, VOIP phone systems and the like. Incoming calls are automatically distributed. [0091] Outgoing calls by automatic priority, such as guard station first, if no answer, the police department over POTS. [0092] Outgoing calls by speed dialing. It is another object and feature of the subject invention to provide access control, such as: [0093] Access granted or denied flashing on map. [0094] Automatic camera switching based on any access attempt. [0095] Automatic camera switching on access denied only. [0096] Mode for manual guard confirmation for all accesses. [0097] Access network appliance powered over Cat-5 wiring. [0098] Access network appliance controlled over IP wiring. [0099] Access control of a network appliance decided by server, or by internal tables. [0100] Access network appliance has internal access allowance tables set over IP wiring. [0101] Access network appliance uses internal tables if server is down. [0102] Access network appliance always uses internal tables (to save bandwidth). [0103] Access network appliance is has encryption. [0104] Access network appliance has contact outputs. [0105] Access network appliance has optional wireless badge reader. [0106] Access network appliance has optional swipe badge reader. [0107] Access network appliance has optional fingerprint reader. [0108] Access network appliance has optional retina scanner. [0109] Access network appliance has link to personal geo-locator such that if authorized person is in close proximity door opens. [0110] Access network appliance opens under local control. [0111] Access network appliance opens under server control. [0112] Access network appliance has tamper detectors reporting over IP. [0113] Access network appliance sends all activity to server for logging. [0114] Access network appliance has local memory for logging all activity. [0115] Access network appliance can send local memory content to server for logging. [0116] Server can request access network appliance data for logging. [0117] Access network appliance is configured over IP. [0118] Access network appliance has HTML server for setup and monitoring. [0119] Access network appliance supports friendly names, such as “East Outside Door”. [0120] Access network appliance has password protection. [0121] Access network appliance has encrypted communications to and/or from. [0122] Access network appliance can communicate over wired LAN (example, cat-5). [0123] Access network appliance can communicate over wireless LAN (example IEEE 802.11B). [0124] Other objects and features will be readily apparent from the accompanying drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS [0125] [0125]FIG. 1 is a perspective view of a room network appliance module in accordance with the subject invention. [0126] [0126]FIG. 2 depicts an overall block-diagram view of a simple implementation of a wall network appliance of the typed shown in FIG. 1. [0127] [0127]FIG. 3 illustrates a network-supported circuit for communicating a time standard to a network appliance for use in event logging or event execution by a network appliance via a local network. [0128] [0128]FIG. 4 shows a configuration including a network hub embedded into the security network appliance. [0129] [0129]FIG. 5 shows a configuration wherein a room network appliance includes wireless networking technologies. [0130] [0130]FIG. 6 illustrates the utility of the room network appliance as configures as an integrated multimedia sensor for a plurality safety-related sensors commonly employed in such a facility. [0131] [0131]FIG. 6A is a wireless version of network appliance shown in FIG. 6. [0132] [0132]FIG. 7 depicts a room network appliance as a gathering point for room environmental data. [0133] [0133]FIG. 7A is a wireless version of the network appliance shown in FIG. 7. [0134] [0134]FIG. 8 illustrates a network appliance enhancement including a video camera, digitizer, motion video compressor, still-frame video compressor, infrared illuminator for dark operation, audio sensor, digitizer, and audio compressor. [0135] [0135]FIG. 8A is a wireless version of the network appliance shown in FIG. 8. [0136] [0136]FIG. 9 illustrates a room network appliance with an alternative alarm source wherein a wireless “panic button” alarm device may activate the system. [0137] [0137]FIG. 9A is a wireless version of the room network appliance shown in FIG. 9. [0138] [0138]FIG. 10 illustrates one method power insertion technique utilizing the LAN data link incorporated in the system of the invention to power a wired network appliance. [0139] [0139]FIG. 11 depicts an alternative embodiment including an alternate power insertion technique whereby DC power conveyed along signal pairs of the cable, in common-mode, in order to power a wired network appliance. [0140] [0140]FIG. 12 depicts a motion detector sensor network appliance with an IP network interface and power receiver. [0141] [0141]FIG. 12A is a wireless version of the network appliance shown in FIG. 12. [0142] [0142]FIG. 13 depicts a networked smoke detector network appliance using the network interface of FIG. 12. [0143] [0143]FIG. 13A is a wireless version of the network appliance shown in FIG. 13. [0144] [0144]FIG. 14 depicts a conventional ‘Pull Handle’ commonly used in institutional fire alarm systems as adapted for incorporation in the networked appliance of the subject invention. [0145] [0145]FIG. 14A is a wireless version of the network appliance shown in FIG. 14. [0146] [0146]FIG. 15 depicts a contact-closure interface, as is commonly used for door or window sensors in alarm systems as adapted as a networked appliance of the subject invention. [0147] [0147]FIG. 15A is a wireless version of the network appliance shown in FIG. 15. [0148] [0148]FIG. 16 depicts a heat sensor network appliance. [0149] [0149]FIG. 16A is a wireless version of the network appliance shown in FIG. 16. [0150] [0150]FIG. 17 depicts a glass breakage sensor network appliance. [0151] [0151]FIG. 17A is a wireless version of the network appliance shown in FIG. 17. [0152] [0152]FIG. 18 depicts an alarm siren network appliance. [0153] [0153]FIG. 18A is a wireless version of the network appliance shown in FIG. 18. [0154] [0154]FIG. 19 depicts a strobe light network appliance. [0155] [0155]FIG. 19A is a wireless version of the network appliance shown in FIG. 19. [0156] [0156]FIG. 20 depicts a thermostat/humidistat network appliance. [0157] [0157]FIG. 20A is a wireless version of the network appliance shown in FIG. 20A. [0158] [0158]FIG. 21 depicts a general-purpose control panel network appliance. [0159] [0159]FIG. 21A is a wireless version of the network appliance shown in FIG. 21. [0160] [0160]FIG. 22 depicts a simple control switch network appliance. [0161] [0161]FIG. 22A is a wireless version of the network appliance shown in FIG. 22. [0162] [0162]FIG. 23 depicts an indicator light panel network appliance. [0163] [0163]FIG. 23A is a wireless version of the network appliance shown in FIG. 23. [0164] [0164]FIG. 24 depicts a networked analog user interface control network appliance, such as may be used to control room lights, temperature, fan speed, louver blind position, loudspeaker volume, and the like. [0165] [0165]FIG. 24A is a wireless version of the network appliance shown in FIG. 24. [0166] [0166]FIG. 25 depicts a loudspeaker network appliance. [0167] [0167]FIG. 25A is a wireless version of the network appliance shown in FIG. 25. [0168] [0168]FIG. 26 depicts a control panel network appliance with indicator lights. [0169] [0169]FIG. 26A is a wireless version of the network appliance shown in FIG. 26. [0170] [0170]FIG. 27 depicts a power outlet network appliance. [0171] [0171]FIG. 27A is a wireless version of the network appliance shown in FIG. 27. [0172] [0172]FIG. 28 illustrates an AC socket as expanded into a network-controlled AC power strip network appliance. [0173] [0173]FIG. 28A is a wireless version of the network appliance shown in FIG. 28. [0174] [0174]FIG. 29 depicts a telephone interface/dialer network appliance. [0175] [0175]FIG. 29A is a wireless version of the network appliance shown in FIG. 29. [0176] [0176]FIG. 30 depicts a lighting fixture network appliance controlled over a network. [0177] [0177]FIG. 30A is a wireless version of the network appliance shown in FIG. 30. [0178] [0178]FIG. 31 depicts an analog wall clock network appliance controlled over the IP network. [0179] [0179]FIG. 31A is a wireless version of the network appliance shown in FIG. 31. [0180] [0180]FIG. 32 depicts an alternative embodiment of the network appliance of FIG. 31, wherein a digital display replaces the stepper motor, gearbox, hands and shaft encoder. [0181] [0181]FIG. 32A is a wireless version of the network appliance shown in FIG. 32. [0182] [0182]FIG. 33 depicts a self-contained magnetic strip reader network appliance, containing a reader as is commonly used in ATM machines, gas pumps, and point-of-sale cash registers. [0183] [0183]FIG. 33A is a wireless version of the network shown in FIG. 33. [0184] [0184]FIG. 34 depicts a proximity card reader network appliance. [0185] [0185]FIG. 34A is a wireless version of the network appliance shown in FIG. 34. [0186] [0186]FIG. 35 depicts an electronic door strike controller network appliance shown controlling a standard elector-mechanical door strike. [0187] [0187]FIG. 35A is a wireless version of the network appliance shown in FIG. 35. [0188] [0188]FIG. 35B is a self-contained electronic door strike network appliance with an integrated IP network interface and electro-mechanical door strike. [0189] [0189]FIG. 35C is a wireless version of the network appliance shown in FIG. 35B. [0190] [0190]FIG. 36 depicts a combination security controller network appliance showing as it is utilized to control an electronic door strike, a door contact switch, a keypad entry system, and a secondary identification component such as a magnetic stripe reader, a proximity sensor or retina reader, or the like. [0191] [0191]FIG. 36A is a wireless version of the network appliance shown in a FIG. 36. [0192] [0192]FIG. 37 depicts a combination security controller network appliance controlling an electric door strike, and sensing door contacts and a proximity sensor FIG. 37A is a wireless version of the network appliance shown in FIG. 37. [0193] [0193]FIG. 37B is an electronic strike network appliance with external contact inputs. [0194] [0194]FIG. 37C is a wireless version of the network appliance shown in FIG. 37B. [0195] [0195]FIG. 38 depicts a combination network appliance that is controlling an electric door strike and sensing door contacts and a magnetic stripe reader. FIG. 38A is a wireless version of the network appliance show in FIG. 38. [0196] [0196]FIG. 39 depicts a keypad entry network appliance with auxiliary electric strike and door contacts. [0197] [0197]FIG. 39A is a wireless version of the network appliance shown in FIG. 39. [0198] [0198]FIG. 40 shows a wireless proximity sensor network appliance. [0199] [0199]FIG. 39A depicts the circuit diagram for the system of FIG. 39 [0200] [0200]FIG. 39B depicts the circuit diagram for a wireless version of the system of FIG. 39. [0201] [0201]FIG. 40 shows a system similar to the system shown in FIG. 39 with the addition of an exit sign. [0202] [0202]FIG. 40A depicts the circuit diagram for the system of FIG. 40. [0203] [0203]FIG. 41 depicts a wired universal interface-pull handle/strobe system. [0204] [0204]FIG. 41A is a wireless version of the system shown in FIG. 41. [0205] [0205]FIG. 42 depicts a wired pull handle system. [0206] [0206]FIG. 42A is a wireless version of the system shown in FIG. 42. [0207] [0207]FIG. 43 depicts a wired exit device. [0208] [0208]FIG. 43A is a wireless version of the system shown in FIG. 43. [0209] [0209]FIG. 44 depicts a wired keypad mortise lock. [0210] [0210]FIG. 44A is a wireless version of the system shown in FIG. 44. [0211] [0211]FIG. 45 depicts a wired magnetic card stripe swipe reader mortise lock. [0212] [0212]FIG. 45A is a wireless version of the system of FIG. 45. [0213] [0213]FIG. 46 depicts a wired proximity card reader mortise lock. [0214] [0214]FIG. 46A is a wireless version of the system of FIG. 46. [0215] [0215]FIG. 47 is a control center system and diagram for connecting various sensors to the system. [0216] [0216]FIG. 47A is a wireless version of the system of FIG. 47. [0217] [0217]FIGS. 48 and 49 depict multiple universal interface applications. [0218] [0218]FIG. 50 is a block diagram of the multiple appliance security system in accordance with the invention. [0219] [0219]FIGS. 51 and 51A-* comprise a full schematic of the system in accordance with the block diagram of FIG. 50. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0220] [0220]FIG. 1 depicts an overall view of the appliance 5 of the subject invention. The appliance contains a variety of devices that are commonplace or useful in educational, institutional, or office environments, including: [0221] A conventional clock display 25 , operable to display other information as needed such as temperature, humidity, alert messages, etc. [0222] A microphone 35 , to detect local ambient sounds in the room and send them to a remote location and, optionally, to support acoustic event detection of gunshots and the like, [0223] A loudspeaker 20 , to allow remote supervisory personnel to communicate with room occupants, [0224] A beacon transmitter 30 , which emits coded infrared, RF, or ultrasonic energy into the room for the purpose of activating personnel locator devices therein, [0225] A beacon receiver also 30 , which detects coded infrared, RF, or ultrasonic energy emitted by locator devices within the room, [0226] A camera 15 , to view live or still scenes in the room and send them to a remote location, [0227] A standard RJ-45 or equivalent connector 40 for connecting to a facility Network. [0228] An antenna 10 may be provided for supporting a wireless connection, as will be explained therein. [0229] [0229]FIG. 2 depicts an overall block-diagram view of a simple implementation, such as may be used in an educational setting. In this implementation, the appliance only supports a clock display 65 , a loudspeaker 45 , and a microphone 55 , to support the ordinary clock and intercom commonly found in schoolrooms. As shown, a digital-to-analog converter 50 and an analog-to-digital converter 60 are used as required for conditioning signals input to and output from the signal processor 70 . The system processor is connected to a network interface 80 , and/or as desired a wireless interface 85 . The wireless interface 85 is in wireless communication with a wireless access point 87 for providing a gateway to the network 90 . [0230] The device is connected to a local-area-network, such as the commonplace 10Base-T, via the network interface. 10Base-T networks commonly employ twisted-pair wiring between hubs and connected devices; an alternative implementation may use IEEE 802.11 or equivalent wireless connections. In either case, the network interface passes information to and from the appliance's processor. The processor controls the clock display. Ambient sounds picked up by the microphone are digitized, compressed, and transmitted to the network via the A/D converter, signal processor, system processor, and network interface. A variety of compression methods and communication protocols may be employed; in the preferred embodiment the audio is compressed using MP3 and sent to the network using the RTP and TCP/IP protocols. Similarly, compressed audio from the network may be received, de-multiplexed, decoded, and played back via the network interface, system processor, signal processor, and D/A converter. [0231] As depicted in FIG. 3, the clock may be set from a time server 110 connected to the local network 115 . A variety of network-based time-transfer methods exist, the most popular and convenient is Network Time Protocol (NTP), a protocol used in conjunction with local-area networks or the Internet. Using NTP, the time server and the client (in this case, the appliance) exchange time messages, and determine a statistical value for network delay, which is then factored out. Accuracies on the order of 1 millisecond are possible on a local network. The timeserver may be set manually, or may optionally be set using a commercially available WWV time receiver 100 or GPS time receiver 105 . As an alternative, the local time server may set itself to an internet-based master timeserver, such as provided by NIST or the U.S. Naval Observatory (USNO) as indicated by the network timeserver 125 , via the network 120 . Various security appliances including the security circuits 94 may be incorporated in the circuit via the network interface 95 . [0232] A useful refinement of the system is depicted in FIG. 4. As there shown, the appliance processor 130 is connected to an embedded network hub 140 via a network interface 135 . Typically, a 10Base-T hub, or equivalent, is embedded into the appliance. [0233] This allows other computers 150 , 155 , printers 145 , or other networked devices (via network 160 ) to share the existing connection from the room to the facility's local area network. By way of an example, remote workstation 157 may be supported in this manner. An archival server 161 is accessible over the network 160 . [0234] The local area network hub may also include wireless networking technologies, such as the IEEE 802.11, as depicted in FIG. 5. In this enhancement a wireless LAN access point 180 and an antenna 175 is provided at the appliance, permitting communication with various wireless remote components or systems such as the printer 195 supported by the wireless adapter 205 and antenna 200 , the wireless desktop PC 215 and antenna 210 , the wireless laptop 225 or other portable device and antenna 220 . [0235] [0235]FIG. 6 illustrates the utility of the room appliance as a collection point for safety-related sensors such as, by way of example, the microwave motion detector 230 , the infrared motion detector 235 , the smoke detector 240 , and the carbon monoxide detector 250 , commonly employed in such a facility. The processor 265 collects data from the various sensors in the room. Such inputs are often simple contact closure inputs. When activated, the appliance alerts a security monitoring station via the local network or via a wide-area network 275 through the network interface 270 . The security station may then summon the appropriate help, such as police, fire, ambulance, or other services as needed. Also, the system processor when so activated may generate an appropriate local warning sound using the D/A converter 260 and the loudspeaker 255 . Appropriate sounds might be a fire horn, alarm bell, klaxon, or the like. The warning sounds may be generated from stored sounds in the processor's memory, or may be generated by the facility security system and transmitted to the room appliance via the intervening network. As shown, various remote stations such as a logging server or archive server 161 , a security monitoring station 280 and other systems such as by way of example the environmental monitoring controller 281 . [0236] [0236]FIG. 6A is a wireless version of the system of FIG. 6. In this enhancement a wireless interface 283 is provided for communicating with a wireless access point 287 to provide a link to the network 275 . Also in this embodiment a power supply 289 and a converter 291 is provided to power the appliance system. In the wired version the network cabling is used to provide power. [0237] [0237]FIG. 7 depicts the room appliance as a gathering point for room environmental data, as may be used in controlling an HVAC system. Various environmental control sensors, such as a relative humidity sensor 285 , temperature sensor 290 , or thermostat panel 295 , may connect to the facility HVAC controller 315 via the room appliance processor 265 and network 310 . Other critical monitoring systems such as, by way of example, the fire alarm controller 316 , may be interconnected to this subsystem via the network. The wireless version is shown in FIG. 7A. [0238] [0238]FIG. 8 illustrates an enhancement to the basic appliance system, wherein a video camera 325 , digitizer 330 , motion video buffer 335 and compressor 340 and, optionally, a still-frame video buffer 345 and compressor 350 is added. An illuminator 320 for low light conditions may also be supplied. When activated, the camera captures local scenes, and transmits them to a monitoring station(s) 390 on the local network or-wide-area network using suitable compression methods such as MPEG or JPEG, via the network comprising the multiplexer 355 , the system or appliance processor 375 and a network interface 380 whereby communication via the network 385 is supported. Simultaneously, the microphone 360 may be included to receive local sounds, digitize them at converter 365 , compress them at compressor 370 , and send them to the same destinations. Activation of the camera and microphone may be accomplished locally via one or more of the attached sensors, or remotely via the network from a monitoring station. If the ambient illumination is insufficient for viewing via the camera, an illuminator may be enabled by command from the appliance's processor or by command from the remote station. The illuminator may be visible light or infrared, as desired. A wireless version is shown in FIG. 8A with an independent power supply 289 , converter 291 and wireless access point 287 is provided as previously described. [0239] An alternative alarm source is depicted in FIG. 9, wherein a wireless “panic button” alarm device 440 may activate the system using the wireless transmitter 445 and receiver 450 , 455 . As shown, the wireless alarm has an RF receiver 455 and transmitter 465 , controlled by the T/R switch 460 , a device ID memory 475 , and a pushbutton switch 480 . A process controller 470 is also provided. During normal usage, the room appliance 485 periodically transmits a code representing its location. The personal alarm 440 receives and stores this location code. When the alarm is activated by pressing the switch 480 , the alarm transmits its device ID and the room ID information to the appliance 440 . This then activates the appliance, enabling the camera and microphone, and alerts the central monitoring station via the intervening network. As shown, the appliance 440 in this configuration includes a compatible RF receiver 400 , T/R switch 405 , RF transmitter 410 with antenna 395 . The appliance processor 425 and network interface 430 communicate with the network 435 as previously described. An encoder 420 may be provided as necessary. FIG. 9A shows the same system with wireless network interfacing as previously described. [0240] [0240]FIGS. 10 and 11 depict a standardized method and apparatus for monitoring, controlling, and powering a variety of network-based appliances, which are subsequently described. This is advantageous when the network-based may be located in an area where conventional AC-operated power is not easily accessible. Referring to FIG. 10, a conventional LAN data link is depicted. The hub's physical-layer interface 800 connects to twisted-pairs 815 and 820 via transformers 805 and 810 . The remote network device's physical-layer interface 830 connects to the same twisted pairs 815 and 820 via transformers 825 and 830 , thus effectuating a conventional LAN connection. Twisted-pair cable typically used in LAN's generally contains 4 pairs, who of which are unused in this example. Accordingly, one or both of the unused twisted-pairs 855 and 865 are employed to convey operating power to the remote device. A power source 840 is disposed at the centralized hub or switch. The power source is preferably a voltage source, and preferably a DC source of moderately high voltage. Typical voltage levels may run in the 30 to 60 Volt range. Current sensor 845 senses the DC current consumed by the remote device, and may cause current limiter 850 to reduce or eliminate any current supplied to the remote device, in the case of a fault in the wiring or in the remote device. At the remote device, power is extracted and regulated by regulator 860 , preferably a switched-mode down-converter of high efficiency. [0241] [0241]FIG. 11 depicts a variation of the same method, wherein the DC power is conveyed along the signal pairs of the cable 855 , 865 , in common-mode. In this example, transformers 805 , 810 , 825 , and 830 are center-tapped, and the power is applied to the center taps of transformers 805 and 810 . Said power is extracted from the center taps of transformers 825 and 830 at the remote device. As before, power is supplied by source 840 , and is monitored and protected by current sensor 845 and limiter 850 . At the remote end, power extracted from the center taps of transformers 825 and 830 is appropriately regulated by regulator 860 . [0242] The network interface, common to all subsequent network devices, here represented as the motion sensor 525 , is depicted in FIG. 12. The device attaches to the network using RJ-45 connector 520 . An Ethernet interface 515 handles the physical-layer connection to the Ethernet network. The required DC operating power, as supplied over the network wiring, passed through RJ-45 connector 520 to the Ethernet Line-Power Interface 510 . This interface extracts the DC power provided by the network, and provides filtering and regulation as necessary to provide the DC operating voltages required by the device via line 505 . The power provided by the network will typically be at a relatively high DC voltage for the sake of transmission efficiency. The Line-Power interface will therefore typically contain one or more regulators to reduce the line-supplied DC voltage to an appropriate value such as the standard 3.3 VDC or 5 VDC. An IP controller 500 is provided. [0243] An additional benefit of the described configuration is that all sensors or appliances are intelligent due to the presence of the preprogrammed IP controller. This allows a centralized system monitoring station to automatically detect and configure the individual sensors or appliances. For example, a device may ‘announce’ itself immediately upon installation, thus becoming automatically recognized and monitored by the centralized monitoring station. Also, relevant operating parameters of the device may be measured or controlled remotely. An example might be a glass breakage detector with a history of false alarms; the sensor's sensitivity may be reduced from the centralized monitoring station via the network. FIG. 12A shows a wireless version of the system depicted in FIG. 12. In this enhancement a wireless interface card 526 and receiver/transmitter 528 is provided at the device, for defining the wireless interface 380 that operates as previously described. [0244] [0244]FIGS. 13 through 34A depict a variety of additional sensors and appliances that may be attached to the described network. All these described devices share a common network interface, allowing any such device to be added to the network as desired. Moreover, all such devices are configured to derive their operating DC power from the network, rather than from locally supplied power. [0245] [0245]FIG. 13 depicts a networked smoke detector, using the same standardized network interface of FIG. 12. The device may also contain a heat sensor, to increase the accuracy of detecting a fire. The smoke and heat sensors 530 and 535 pass their data to the IP controller 500 , which generates and transmits a predefined message to the network. Note that the heat sensor may pass an actual numerical value for temperature to the network if desired, rather than a simple 1-bit indication that a temperature threshold has been exceeded. FIG. 13A is the wireless version and corresponds to the circuit shown in FIG. 12A. [0246] [0246]FIG. 14 depicts a conventional ‘Pull Handle’ commonly used in institutional fire alarm systems. In this case, the input to the IP controller 500 is a simple 1-bit input from the pull handle switch 540 . Again, the device sends a predefined IP message to the network and system monitoring station upon activation. FIG. 14 is the wireless version. [0247] [0247]FIG. 15 depicts a simple contact-closure interface, as is commonly used for door or window sensors in alarm systems. The sensors often contain a magnet in one module, and a magnetic reed switch in the other module. In this implementation, the contact closure thus effectuated by the reed switch 545 becomes input bit into the IP controller 500 . In response to a change in switch status, the controller 500 generates and transmits a predefined IP message via the Ethernet interface to the network and associated monitoring apparatus. FIG. 15A is the wireless version. [0248] [0248]FIG. 16 depicts a networked heat sensor. The sensor 550 may produce a simple one-bit ‘threshold crossed’ indication to the controller 500 , or may pass a variable representing actual sensed temperature. In either case, the IP controller 500 generates and transmits a predefined IP message to the network and associated monitoring apparatus. As an additional refinement, the device may be programmed to accept configuration commands from the networked monitoring apparatus. Such commands may, for example, change the sensor's trip point or temporarily suspend the transmission of messages. FIG. 16A is the wireless version. [0249] A networked glass breakage sensor is depicted in FIG. 17. Sensor 555 produces an output indicative of breaking glass to the IP controller 500 , which generates a predefined IP message and transmits said message to the network. The sensor's output may, if necessary be processed or analyzed by controller 500 in the case of a simple microphone or vibration sensor. The device may additionally be configured to respond to incoming control and configuration messages from the network, such as commands to change the sensor's sensitivity or to temporarily disable the device. FIG. 17 is the wireless version. [0250] [0250]FIGS. 18 and 19 depict a networked alarm siren and strobe light respectively. The IP controller 500 receives IP messages from the network and controls the alarm 560 or strobe light 565 respectively. Network messages may be used to turn the alarm or strobe on or off, or may control other characteristics of the device such as volume, flash rate, etc. The IP controller may also send status messages to the network, either in response to inquiries from control devices or at regular intervals. FIGS. 18A and 19A are the wireless versions, respectively. [0251] [0251]FIG. 20 depicts a networked thermostat or humidistat, or both combined. The temperature sensor 570 and/or humidity sensor 575 produce signals indicative of local temperature and/or humidity. As before, IP controller 500 generates and transmits predefined messages to the network representing the current values of temperature and/or humidity. In addition, switches 580 and 585 allow a user to increase or decrease the desired temperature setting. Contact closures produced by switches 580 or 585 are detected by IP controller 500 and transmitted via IP messages to a monitoring and/or control device disposed on the network. In addition, display 590 displays the current value of the local temperature and/or temperature setting. The temperature displayed may be generated locally by the controller 500 or may be commanded by a networked monitoring and control device via IP messaging. FIG. 20A is the wireless version of the thermostat/humidistat network appliance. [0252] A general-purpose control panel network appliance is depicted in FIG. 21. This is a highly flexible device that can be used for several multimedia monitoring functions, as well as many control functions. For example, the control network appliance can be utilized as a conventional type control keypad for alarm system functions. It also could be utilized for lighting control, HVAC control, pump control, fan control, volume control, and other facility management founctions. A keypad 595 and display 600 are connected to the IP controller 500 . The controller 500 detects and interprets keystrokes on keypad 595 , and generates appropriate IP messages for transmission over the intervening network to a networked monitoring and control station. Similarly, a networked monitoring and control station may generate messages to be displayed on the control panel's display 600 . Said messages are transmitted from the monitoring and control station via the IP network to the controller 500 , which causes the appropriate message to be displayed. Speaker 601 is provided for audible indications of keypad depression, status, alarms and for streaming of audio streams. [0253] [0253]FIG. 21A is the wireless version of the control panel network appliance. [0254] [0254]FIG. 22 depicts a simple control switch network appliance. The switch 605 may be a toggle, rocker, or push-button switch as appropriate. The status of switch 605 is detected by IP controller 500 , which generates and transmits an appropriate message over the IP network to a networked monitoring and control station. The appliance may be configured to generate “on” and “off” signals for controlling a two state device, or with a center return momentary switch, can generate streams of “up” and “down” signal steams relating to the length of time that the button is held for “analog” controlling of devices. [0255] [0255]FIG. 22A is the wireless version of the control switch network appliance. [0256] An indicator light network appliance is depicted in FIG. 23. IP controller 500 receives messages from a networked monitoring and control station, and thereupon causes the appropriate lamp or lamps in light array 610 to be illuminated or extinguished. FIG. 23A is the wireless version of the indicator light network appliance. [0257] [0257]FIG. 24 depicts an analog control device network appliance, such as may be used to control room lights, temperature, loudspeaker volume, fan speed and the like. IP controller 500 receives input from potentiometer 615 or shaft encoder 620 , and thereupon generates appropriate IP messages and transmits them via the intervening IP network to a networked monitoring and control station. [0258] [0258]FIG. 24A is the wireless analog control device network appliance. [0259] A networked loudspeaker appliance is depicted in FIG. 25. In the preferred embodiment, the device receives a stream of data representing audio from the IP network. IP controller 500 passes this data to processor 625 , which decodes the data stream and generates an appropriate analog signal for reproduction via loudspeaker 630 . Control signals such as speaker amplifier gain, tone controls and the like can be sent to the loudspeaker appliance via the network. [0260] [0260]FIG. 25A is the wireless version of the loudspeaker network appliance. [0261] A control panel network appliance, with indicator lights is depicted in FIG. 26. Switches 635 and 640 cause the IP controller 500 to generate and transmit IP messages to a networked monitoring and control station. Additionally, a networked monitoring and control station may generate appropriate IP messages to control the status of lamps 645 , 650 , and 655 via the intervening network and IP controller 500 . FIG. 26A is the wireless version of the control panel network appliance. [0262] A networked power outlet is depicted in FIG. 27. In this device, the IP controller 500 controls the status of an AC power switch 670 in response to received IP messages from a networked monitoring and control station. The networked monitoring and control station may thereby turn an AC-powered appliance ON or OFF via networked IP messages. Alternatively, power switch 670 may be replaced with a dimmer module, to allow dimming of a lamp from the networked monitoring and control station. Additionally, an RJ-45 socket 665 may be installed on the device, to provide a local user with an Ethernet connection into the network. Effectively this allows the power control module to act as a network hub as well. Since the network connection to the network is already in use by the system controller 500 , when another network connection port is needed such as 665 , it is necessary to implement a simple three-port network hub 660 between the network physical-layer interface 515 and the RJ-45 connector to the network 520 . [0263] [0263]FIG. 27A is the wireless version. In the preferred embodiment the power for the network interface and control circuits are taken from the incoming AC power. [0264] In FIG. 28, the network-controlled AC socket is expanded into a network-controlled AC power strip appliance. As previously described in FIG. 27, the IP controller 500 controls a switch or dimmer 670 in response to IP messages received via the network from a monitoring and control station. In this embodiment, multiple AC sockets 675 are provided. In addition, a circuit breaker 680 protects the device from overload. Surge protectors can also be implemented. Additional circuits can can read the status of the power strip, such as the state of the circuit breaker, input voltage and the status of the surge protector. The current load of the power strip can also be measured. This allows for extensive “remote management” of the power strip over the network such as from a network operations center (NOC). Multiple power controllers, such as 670 , can be implemted such as one for each plug. This allows independent control of each plug. This could allow remote power cycling of a bank of network computers, for example, or would allow control of multiple temporary lighting circuits, stage lights, etc. Although the power strip network appliance can be powered by the incoming AC power line, if the power is not present the status of the strip could not be read. The network and control circuits can,however, be powered by the network connection as is described elsewhere in this application. This would allow the network devices to read the managed power strip status even if the incoming AC power is not available or the circuit breaker is tripped. [0265] [0265]FIG. 28A is the wireless version of the power strip network appliance. [0266] [0266]FIG. 29 depicts a network-controlled telephone dialer/interface, preferably housed in a standard telephone wall socket. A standard POTS telephone line or telephone is plugged into the telephone line 700 via RJ-11 socket 705 . VOIP data can then be transferred from the phone line to the network, and from the network to the telephone line. If a central office (CO) line or private branch exchange (PBX) line is plugged into the RJ-11 jack, the RJ-11 interface is configured as a virtual telephone instrument. If a POTS telephone instrument is plugged into the RJ-11 socket, the RJ-11 interface is configured as a virtual telephone line. When configured as a virtual instrument, the IP controller 500 , in response to commands received from the IP network, energizes relay 695 , thus seizing telephone line 700 . The IP controller 500 thereupon, in response to IP commands received via the IP network, causes DTMF generator 685 to produce the desired DTMF tones on telephone line 700 via line transformer 690 . The interface also monitors the line to detect ringing and to detect caller-ID (CLID) data, and communicates that date via the LAN, then awaits for instuction to seize the telephone line. When configured as a virtual line, the network appliance supplies talk battery to the POT S telephone to power the telephone, the tone dial, and to detect off-hook conditions. It also generates a ring voltage to ring the POTS telephone when instructed to do so from instructions received over the network. This device has several uses in the multimedia system. It can be used to provide an interface to emergency telephones that are in communication with monitor stations. It is also used to interface to the telephone line for dialing and signaling under the control of the event notification services as is described in my other patents/patent applications. It also can be used a stand-alone relay for a voice circuit between a pair if, or more, telephones, emulating an “order wire”. It also can be used as a bridge, providing a remote POTS telephone line via a LAN or WAN to another location for a POTS telephone instrument. [0267] [0267]FIG. 29A is the wireless version of the telephone dialer/interface network appliance. [0268] [0268]FIG. 30 depicts a lighting fixture network appliance controlled over the network. As in FIG. 27, IP controller 500 turns the light ON or OFF, or may dim the light, in response to IP messages received from a monitoring and control station via the network. The appliance can also monitor the status of the bulb and report over the network. This “managed bulb” can then be interrogated from a NOC, or a burned out bulb can generate an event that is notified to maintenance personnel for action by the notification services as described by my other patents/applications. [0269] [0269]FIG. 30A is the wireless version of the lighting fixture network appliance. [0270] [0270]FIG. 31 depicts an analog wall clock network appliance controlled by the IP network. IP controller- 500 maintains an accurate knowledge of local time through periodic synchronization with a network time standard via SNTP or other appropriate network-time protocols. IP controller 500 drives a stepper motor 720 , which drives hands 735 , 740 , and 745 via gear train 730 . Shaft encoder 725 provides shaft position feedback information to IP controller 500 , to allow the clock to be set after a power failure. The shaft encoder may be as simple as a one-bit indication that the hands are all in the 12:00 position. [0271] [0271]FIG. 31A is the wireless version of the analog wall clock network appliance. [0272] [0272]FIG. 32 depicts an alternative embodiment, the digital clock network appliance, wherein a digital display 735 and drive electronics replaces the stepper motor 720 , gearbox 730 , hands 735 , 740 , and 745 , and shaft encoder 725 . As before, IP controller 500 maintains accurate time via periodic synchronization over the IP network. [0273] [0273]FIG. 32A is the wireless version digital clock network appliance. [0274] [0274]FIG. 33 depicts a magnetic strip reader network appliance. The magnetic strip reader, as commonly used in ATM machines, gas pumps, and point-of-sale cash registers. Card reader 750 passes data extracted from the card to IP controller 500 , which thereupon transmits the card data to a device on the IP network for appropriate processing. The card data is preferentially encrypted by IP controller before transmission, to provide security. [0275] [0275]FIG. 33A is the wireless version magnetic strip reader network appliance. [0276] [0276]FIG. 34 depicts a proximity card reader network appliance. This incorporates a proximity ID card readers, as commonly used at door entrances. IP controller 500 receives data detected by badge sensor 755 , and passes an appropriate predefined IP message to a networked monitoring and control station. [0277] [0277]FIG. 34 depicts a proximity card reader network appliance. This incorporates a proximity ID card readers, as commonly used at door entrances. IP controller 500 receives data detected by badge sensor 755 , and passes an appropriate predefined IP message to a networked monitoring and control station. [0278] [0278]FIG. 34A is the wireless proximity card reader network appliance. [0279] It is an important feature of the subject invention that legacy sensors, alarms and devices may be connected to the multimedia network system without modification of the legacy devices, permitting signals generated by the legacy devices to be communicated via and managed by the system of the subject invention. FIGS. 35 - 38 are examples of security network appliances that provide such enhancements. An important component of this feature is a common interface permitting the communication of the signals generated by the legacy device to the network supporting the system of the subject invention. One common interface network appliance device 900 is shown in FIG. 35 and includes two terminals or connectors 901 , 902 for connecting the output wires 904 , 905 of a legacy device, here an electric door strike 906 , to the network. The network connection is made via a wire connected at the RJ-45 jack 908 . [0280] As shown in FIG. 35A, the legacy device can also be connected via wireless interface 910 . In this version, a power adapter 912 is provided for driving the interface 910 . A wireless transmitter/receiver card 914 is added to provide the wireless network connection. In the wired version, the connector wire connected to the RJ-45 jack 908 is ideally used to provide power. However, a separate power supply can be provided where desired. FIG. 35B shows an electric strike 906 with an RJ45 jack 908 . FIG. 35C is the wireless version. FIG. 34 depicts a proximity card reader network appliance. This incorporates a proximity ID card readers, as commonly used at door entrances. IP controller 500 receives data detected by badge sensor 755 , and passes an appropriate predefined IP message to a networked monitoring and control station. [0281] [0281]FIG. 34A is the wireless proximity card reader network appliance. [0282] It is an important feature of the subject invention that legacy sensors, alarms and devices may be connected to the multimedia network system without modification of the legacy devices, permitting signals generated by the legacy devices to be communicated via and managed by the system of the subject invention. FIGS. 35 - 38 are examples of security network appliances that provide such enhancements. An important component of this feature is a common interface permitting the communication of the signals generated by the legacy device to the network supporting the system of the subject invention. One common interface network appliance device 900 is shown in FIG. 35 and includes two terminals or connectors 901 , 902 for connecting the output wires 904 , 905 of a legacy device, here an electric door strike 906 , to the network. The network connection is made via a wire connected at the RJ-45 jack 908 . [0283] As shown in FIG. 35A, the legacy device can also be connected via wireless interface 910 . In this version, a power adapter 912 is provided for driving the interface 910 . A wireless transmitter/receiver card 914 is added to provide the wireless network connection. In the wired version, the connector wire connected to the RJ-45 jack 908 is ideally used to provide power. However, a separate power supply can be provided where desired. FIG. 35B shows an electric strike 906 with an RJ45 jack 908 . FIG. 35C is the wireless version. [0284] Multiple legacy appliances may be connected to a common interface network appliance system as shown in FIG. 36 (wired version) and FIG. 36A (wireless version). As there shown, the interface 920 has multiple terminals 901 , 902 , 920 , 921 and 922 for contact type devices and/or appliance jacks 924 , 925 , such as could be in communication with RS-232 signals, for connecting numerous legacy appliances such as the retina reader 926 , proximity reader 927 , swipe reader 928 and keypad display 929 . All of these are connected to the network via a connector such as a wire via RJ-45 jack 908 (FIG. 36) or via a wireless connection card 914 (FIG. 36A). As before, the power supply 912 may be used in either version. [0285] [0285]FIG. 37 is an enhancement wherein a network sensor in accordance with the subject invention includes an integrated interface for connecting a legacy appliance to the network via the network sensor system. In this enhancement the proximity reader/controller 930 has an LED sensor 931 as is well known in the art and includes an RJ-45 jack for connecting the sensor to the network. As previously described, a wireless version is also supported. The sensor includes terminals or connectors 901 , 902 and 920 for connecting various legacy appliances such as, by way of example the electric door strike 906 or the door contacts 923 . FIG. 37A shows the wireless version. FIG. 37B shows a door strike 906 with an R45 jack 924 and optional door contacts 923 . FIG. 37C is the wireless version. [0286] Other sensors/devices may be similarly enhanced, as shown with the swipe reader 932 of FIG. 38. [0287] [0287] 38 A is the wireless version of 38 . [0288] A keypad entry appliance 934 is similarly enhanced as shown in FIG. 39. [0289] [0289] 39 A is the wireless version of 39 . [0290] A further enhancement is shown in FIGS. 40 - 40 C. In this enhancement a wireless proximity sensor 934 for monitoring movement within the marked zones, see zone 936 , around monitored door 938 is connected to the network via the wireless transmitter/receiver card 526 and antenna 528 to a wireless access point interface 287 . As is better shown in FIG. 40A, the circuitry for supporting this sensor 934 is identical to the circuitry shown and described in FIG. ??. The wireless version is shown in FIG. ?? and is consistent with the circuitry shown in FIG. ??A. [0291] [0291]FIGS. 40C and 40D show an enhancement of the door proximity sensor shown in FIG. ?? with a message display such as, by way of example, the EXIT display 940 . In this configuration a power supply comprising the AC input, a transformer 942 and a battery charger 944 provides power to the display. This provides power to the lamp display 940 in the normal manner, and can also be used to power the IP controller 500 . [0292] The wireless connection can be made via a wireless antenna 943 or by coupling to the AC power wiring 945 such as through RF coupling capacitors 947 . The wireless/power carrier version is shown in FIG. 40D and is consistent with the changes made in the previously discussed embodiments. [0293] [0293]FIGS. 41 and 41A show a wired universal interface network appliance and wireless universal interface network interface, respectively. This configuration of the interface 946 includes an independent connection to a power supply as indicated at 948 , or may be powered over the LAN 950 as has been previously discussed. The LAN connection such as the RJ-45 jack 950 in the configuration of FIG. 41 or the wireless connector 952 of FIG. 41A may be utilized. A plurality of terminal connectors 954 are provided for connecting the legacy devices such as the fire strobe display alarm 956 and the pull-handle alarm 958 . The legacy devices can be powered from the LAN also, utilizing the power output terminals at 954 . [0294] [0294]FIG. 42 shows a pull-handle network appliance 959 modified for direct network hook-up using a wired RJ-45 jack 960 . FIG. 42A is a wireless version of the pull-handle network appliance with the wireless modifications previously described. [0295] A wired exit device network appliance is shown in FIG. 43. The wireless version of the exit device network appliance is shown in FIG. 43A. In this enhancement the exit device includes a latch 962 , a push bar 964 and a key lock 966 . Action on any of these elements will transmit a signal via wire 968 to show activity at the door. The wire is connected to terminals on the universal interface 946 , which is in turn connected to the network 970 via a CAT-5 wire or other cabling to the universal interface. A wireless version is shown in FIG. 43A and includes the external power supply 289 , the wireless access component 380 , and the wireless access point 287 , as with previously described enhancements. [0296] A keypad mortise lock entry device network appliance is shown in FIG. 44, with the wireless version being depicted in FIG. 44A. The keypad lock device 972 includes a keypad 974 , backup key lock 976 and a door handle 976 , each of which will generate a signal when activated. The signal is carried from the control box 980 to a universal interface 946 for connection to the LAN 970 . A wireless version is shown in FIG. 44A. [0297] The keypad lock 974 is replaced by a card 986 and swipe reader 984 in FIG. 45 (wired) and FIG. 45A (wireless). A magnetic or optical card reader 990 and compatible card 992 is shown in FIG. 46 (wired) and FIG. 46A (wireless). [0298] An alternative universal connector interface network appliance 996 is shown in FIGS. 47 (wired) and 47 A (wireless). The universal connector interface network appliance includes a plurality of terminals for providing power out ( 998 ), input from legacy devices ( 999 ) and various output signals other than network ( 1000 ). Applications of the universal interface network appliance are shown in FIG. 48 wherein an electric strike 1002 and latch 1004 , an electric strike 1006 and a magnetic contact 1008 . FIG. 49 shows additional universal interface applications using legacy appliances. [0299] [0299]FIG. 50 is block diagram of the circuitry for supporting a multiple appliance security system in accordance with the subject invention. The full schematic is shown in FIGS. 51 and 51A- 51 BB. With reference to FIG. 50, the security appliance 5 includes a system processor 75 having both Read Only Memory (ROM) and Random Access Memory (RAM) components 1025 and 1026 , respectively. A contact closure interface 1028 is provided for connecting any combination of simple external appliances to the security appliance center. Specifically, these appliances are generally limited to ON/OFF conditions and responses The RS-232 interface 1030 is provided for connecting more sophisticated external appliances such as, by way of example, the listed appliances and the appliances described elsewhere herein. A DTMF/CLID detector 1032 and phone line circuit monitor 1034 provides connection to an external telephone 1036 and to the telephone network 1038 . External power is provided to the system either through the wired LAN interface 80 and the network power module 1040 . External power may also be provided by the power supply 289 or through the option AC power brick 1042 . The system is capable of wireless connection to the network 90 via the wireless network interface 85 and the wireless access point 87 , or alternatively by wired connection to the network via network interface 80 . [0300] While certain embodiments and features of the invention have been described in detail herein, it will be readily understood that the invention includes all modifications and enhancements within the scope and spirit of the following claims.
Network appliances for use in combination with a network based full service, multi-media surveillance system provide a wide range of monitoring techniques utilizing digital network architecture. The appliances may be connected to the surveillance system for transmitting event data, video and/or image monitoring information, audio signals and other data over significant distances using digital data transmission over networks such as a local area network (LAN), a wireless LAN (WLAN), a wide area network such as the Internet for other networks, permitting remote manual and/or automatic assessment and response. The wireless LAN connectivity permits local distribution of sensor information audio, video and image data with relatively high bandwidth without requirement of a license and without relying on a common carrier and the fees associated therewith. The surveillance system may be interfaced with a WAN (wide area network) such as frame relay or the Internet for providing a worldwide, low cost surveillance system with virtually unlimited geographic application. Multiple sensors and appliances may be accommodated, as required. The topology of the network will be established by the geographic situation of the specific installation. Appropriate firewalls may be set up as desired to protect unauthorized access to the system or collected data. The server based system permits a security provider to have access to the appliance, related sensor and surveillance data or to configure or reconfigure the system from any station on the Intranet or Internet. The use of power supplied over LAN wiring to various configurations of security network appliances provides an important simplification and cost reduction of the installation of various alarm and security system devices, such as card readers and scanners, audible devices, strobe enunciators, keypads, motion detectors, and the like. The use of networked sensors in the form of network appliances allows various servers and monitors to share common sensors, further reducing installation costs and greatly increased flexibility.
Condense the core contents of the given document.
[ "BACKGROUND OF THE INVENTION [0001] 1.", "Field of the Invention [0002] The subject invention is generally related to sensor, monitor and control appliance devices generally utilized in monitoring and surveillance systems and is specifically directed to a network adaptation of such appliances.", "[0003] 2.", "Discussion of the Prior Art [0004] Security of public facilities such as schools, banks, airports, arenas and the like is a topic of increasing concern in recent years.", "Over the past few years, a number of violent incidents including bombings, shootings, arson, and hostage situations have occurred.", "In addition, agencies responsible for public security in these facilities must cope with more commonplace crimes, such as drug dealing, vandalism, theft and the like.", "[0005] Such facilities frequently employ monitoring and surveillance systems and access control systems to enhance security.", "This has been common practice for a number of years.", "Such systems generally have a centralized monitoring console, usually attended by a guard or dispatcher.", "A variety of sensors are located throughout the facility, such as smoke detectors, fire detectors, motion sensors, glass breakage detectors, badge readers at various access points, and sometimes, video cameras and/or microphones.", "Other sensors and transducers are utilized to lock and unlock doors.", "[0006] There are numerous devices utilized to collect information at remote locations and initiate a local alarm, store the information for later retrieval or forward the information to a remote location for storage and/or near real time review.", "Examples include fire alarms, security cameras, motion sensors, proximity switches, heat sensors, smoke and fire sensors, and the like.", "Almost all of these appliances can be used in some form of configuration where one or more sensors may be used in combination to provide a surveillance scheme over an area to be monitored.", "In prior art systems, the signal generated by each type of device was used locally, or if part of a network, was sent over a dedicated connection to a remote collection point for that type of device.", "[0007] These prior-art devices often use technologies that not ‘intelligent’ in the modern sense;", "they merely provide an ‘ON/OFF’ indication to the centralized monitoring system.", "The appliances also are not ‘networked’ in the modern sense;", "they are generally hard-wired to the centralized monitoring system via a ‘current loop’ or similar arrangement, and do not provide situational data other than their ON/OFF status.", "SUMMARY OF THE INVENTION [0008] The subject invention is directed to support function systems that may be used separately or in combination as building support devices by adapting them to network appliances and configuring them to communicate over network topologies to each other, to building databases, and to the users.", "This allows either stand alone functional systems, or a fully integrating them into a single “seamless”", "system.", "By way of example, school classrooms may have several communications and monitoring systems to support a classroom such as an intercom, clock system, thermostat, motion detector, door access control, computer network connections and the like.", "The subject invention permits the combination of all of these functions into a single device that may communicate over a single network connection providing various combinations to provide for building support functions.", "The devices may also communicate to other buildings and control nodes in other facilities by use of Wide Area Networks (WANs) such as Intranets and the Internet.", "[0009] The invention is particularly well adapted for use in connection with my co-pending patent applications, entitled: Multimedia Surveillance and Monitoring System Including Network Configuration, Ser.", "No. 09/594,041, filed on Jun. 14, 2000;", "Method and Apparatus for Distributing Digitized Streaming Video Over a Network, Ser.", "No. 09/716,141, filed on Nov. 17, 2000;", "and Method and Apparatus for Collecting, Sending, Archiving and Retrieving Motion Video and Still Images and Notification of Detected Events, Ser.", "No. 09/853,274, filed May 11, 2001, and incorporated by reference herein.", "[0010] The subject invention includes specific network appliances designed to participate in a comprehensive multimedia security and building support system that may be deployed singularly or in combination to achieve the degree of monitoring and protection desired.", "[0011] The subject invention also permits all of the support functions to be combined in one appliance, achieving both improved functionality and support at a lower costs because of use of shared components, shared wiring and shared network connectivity.", "In the preferred embodiment, the appliance is connected to a single Category5 (CAT5) wire, fiber or the like to the system network.", "The single appliance provides all of the functions previously supplied by a plurality of dedicated purpose discrete appliances.", "[0012] Functional superiority over the discrete appliances is also achieved because of the opportunity to integrate the various subsystems common in the appliances.", "For example, a universal wall appliance in accordance with the subject invention can use a common display panel for a clock/bell system and a visual alarm.", "A single microphone can be shared for the intercom, for noise detection and for alarm oral response or activation.", "A single speaker can be utilized for the intercom, a telephone call bell, an alarm emitter and a clock/bell sound emitter.", "A single temperature sensor can be shared between a fire alarm system, the HVAC system and be utilized to check for appliances proper ambient operating temperature environment.", "A wireless LAN access point can be shared for remote or mobile alarm/sensor/display modules and for classroom computer access.", "A single video camera can be shared for security monitoring, video conferencing and distance learning.", "A single streaming audio/video decoder can present Video On Demand (VOD) classroom video presentations, broadcast television and video conferencing.", "[0013] The subject invention permits network components and appliances to be used in combination with a network based full service, multi-media surveillance system capable of a wide range of monitoring techniques utilizing digital network architecture.", "[0014] Schools, banks, retail operations and other security conscious businesses and institutions have a need for advanced hardware and software solutions that provide total, user friendly control over their surveillance and monitoring equipment.", "A system desirably provides: [0015] 1.", "Multimedia data collection;", "[0016] 2.", "Automated control;", "[0017] 3.", "Archive storage;", "[0018] 4.", "Enhanced search and recall of archived event recordings;", "[0019] 5.", "Preset responses to triggers and triggering events;", "[0020] 6.", "Remote viewing and management from a wide area network including, preferably, the World Wide Web (or Internet) accessibility.", "[0021] 7.", "Automatic system pre-failure prediction and post failure analysis.", "[0022] 8.", "Common infrastructure and workstations shared with other co-located systems.", "[0023] 9.", "Wireless infrastructure for sensors, monitors and shared applications/systems.", "[0024] In accordance with the teachings of the subject invention, any or a plurality of distinctive appliances may be connected to the comprehensive, wired/wireless multimedia surveillance and monitoring system for transmitting event data, video and/or image monitoring information, audio signals and other network appliance sensor and detector data over significant distances using digital data transmission over networks such as a local area network (LAN), a wireless LAN (WLAN), a wide area network (WAN) such as the Internet for other network automatic event recording, assessment and response, including dispatch of response personnel.", "Wired, wireless and optical appliances and sensor systems may be employed.", "The wireless LAN connectivity permits local distribution of sensor, audio, video and image data with relatively high bandwidth without expensive local wiring/fiber and without the requirement of a license and without relying on a common carrier and the fees associated therewith.", "The surveillance system may be interfaced with a WAN (wide area network) such as optical fiber, frame relay or the Internet for providing a worldwide, low cost surveillance system with virtually unlimited geographic application.", "Centralized and distributed remote monitoring stations have access to all of the surveillance data from various remote locations via the network or the WAN.", "A server provides a centralized location for data collection, alarm detection and processing, access control, auto response generation, paging, automatic e-mail generation, telephone dialing and message transmission, dispatch processing, logging functions, configuration management, and/or other specialized functions.", "The server may be inserted virtually anywhere in the Intranet/Internet network, and may be segmented and installed in a distributed manner to further add to system security, reduce bandwidth requirements, or allow redundancy.", "[0025] Multiple sensors and appliances may be accommodated, as required.", "The topology of the network will be established by the geographic situation of the specific installation.", "Appropriate firewalls, encryption and access codes may be set up as desired to protect unauthorized access to the system or collected data.", "The server based system permits a security provider to have access to the appliance, related sensor and surveillance data or to configure or reconfigure the system from any station on the Intranet or Internet.", "[0026] The system of the subject invention permits comprehensive monitoring of locations over great distances with sufficient performance to provide widespread use as a security surveillance device.", "[0027] The subject invention is specifically directed to networked appliances such as video and/or image appliances, access control devices, detectors and sensors as well as audio, condition and/or event monitoring systems.", "In its preferred form, the comprehensive multimedia safety and surveillance system of the subject invention provides both visual and audio information as well as critical data such as temperature fire and smoke detection.", "Manually operated transducers, such as panic buttons, door contacts, floor sensors, and the like may also be included to activate the system in the presence of an event at the sensor location, such as a fire alarm or security alarm panic bar or the like.", "Controlled transducers, such as electric door strikes, magnetic door strikes, electric door openers, strobe lights, sirens, room lights, fire control equipment and the like can be controlled by the appliances.", "Numerous appliances, including but not limited to detection and sensor systems, are utilized to provide monitoring stations or personnel, such as security personnel, and/or a base station monitoring critical information from the sensor system and to record the information and permit reconstruction of events after the fact.", "[0028] In its preferred form, a plurality of sensor units, which may include at least one video image appliance sensor and/or at least one audio appliance sensor and/or at least one motion appliance sensor and/or other sensors, are placed strategically about the facility to be monitored.", "In addition, strategically placed motion detectors, fire sensors, panic switches, smoke sensors and other monitoring equipment is incorporated in the system.", "Cameras may be placed throughout the facility and in other desired spaces including on the grounds outside the facility.", "The audio sensors/transducers and other sensors and detectors are also strategically located both internal and external of the facility.", "[0029] While the appliances of the subject system may be hardwired, in its preferred form the system of the present invention is adapted for use in connection with wireless transmission and receiving systems.", "The wireless system is particularly useful for adapting the system as a retrofit in existing facilities and also provides assurances against disruption of data transmission such as during a fire, as well as permitting roving interactive monitors that can be carried or worn.", "In the preferred embodiment, the wireless system is fully self-contained with each appliance and/or sensor unit having an independent power supply and, where required for image sensors, a sensor light source.", "The security system may include either motion sensitive, audio sensitive and/or image processing based activation systems so that the equipment is not activated until some event is detected, i.e., the system is action triggered.", "[0030] In the preferred embodiment, each appliance will transmit any detected information to a monitor system located at a base monitoring station, located on site and/or at a remote or roving location, and/or a server for logging, forwarding, archiving same.", "The base station has instant live access to all of the image and audio signals as they are captured by the sensors, and where desired is adapted to record and make an historic record of the images for archive purposes.", "Where random access recording techniques are used, such as, by way of example, digital random access memory storage devices or high speed disk storage arrays, the archive may be readily searched for stored information.", "[0031] One significant advantage to the appliance configuration of the subject invention is that it permits multimedia surveillance in applications and locations where physical wiring cannot be used, and over distances not possible or not cost effective with other systems.", "The system of the present invention provides surveillance capability utilizing techniques ranging from closed-circuit, hard wired systems to the Internet based techniques and is not limited by the data capacity;", "or cost associated with systems currently on the market.", "[0032] It is, therefore, an object and feature of the subject invention to provide both wired and wireless communication links between appliances, sensors, monitors and/or sensors.", "[0033] It is an additional object and feature of the subject invention to provide an appliance configuration for a multimedia surveillance system adapted for any of a plurality of monitoring and surveillance appliances which may be incorporated in the system via network connections through a server to provide a versatile, wide-ranging multi-media system which may be configured to meet specific application needs.", "[0034] It is an additional object and feature of the subject invention to provide an appliance and monitoring station configuration for a multimedia surveillance system adapted for a plurality simultaneously operating geographically distributed monitoring stations.", "[0035] It is another object and feature of the subject invention to provide appliances adapted for use in connection with a surveillance system for transmitting data over significant distances using typical bandwidth carriers such as the public telephone system, and wireless carriers such as cellular telephones, including AMPS, PCS, GSM, CDMA, wide band CDMA and the like, CDPD data links, two-way pagers, satellite networks such as Iridium and the like.", "[0036] It is another object and feature of the subject invention to provide appliances adapted for use in connection with a surveillance system for transmitting data over significant distances using typical broadband carriers such as cable TV networks, dedicated fiber optics networks, DSL and ADSL carriers, and forthcoming broadband wireless networks.", "[0037] It is also an object and feature of the subject invention to provide appliances for a surveillance system adapted for utilizing wired video and/or image data collection and/or transmission using the Internet and/or IP protocols.", "[0038] It is also an object and feature of the subject invention to provide appliances for a surveillance system adapted for utilizing wireless video and/or image data collection and/or transmission using the Internet and/or IP protocols.", "[0039] It is also an object and feature of the subject invention to utilize network communication systems to distribute both appliance surveillance data and control data.", "[0040] It is another object and feature of the subject invention to provide network appliances for a security surveillance system adapted for use in connection with a wireless LAN (WLAN) communications system, such as the IEEE 802.11 standards and follow-on standards.", "[0041] It is another object and feature of the subject invention to provide time display to a network appliance communicating over the IP network.", "[0042] It is another object and feature of the subject invention to provide emergency event annunciation to a network appliance communicating over the IP network.", "[0043] It is another object and feature of the subject invention to provide room paging through a network appliance communicating over the IP network.", "[0044] It is another object and feature of the subject invention to provide room audio monitoring utilizing a network appliance communicating over the IP network.", "[0045] It is another object and feature of the subject invention to provide room intercom utilizing a network appliance communicating over the IP network.", "[0046] It is another object and feature of the subject invention to provide room temperature sensing using a network appliance communicating over the IP network.", "[0047] It is another object and feature of the subject invention to provide device temperature sensing using a network appliance communicating over the IP network.", "[0048] It is another object and feature of the subject invention to provide room gunshot detection utilizing a network appliance communicating over the IP network.", "[0049] It is another object and feature of the subject invention to provide room access control utilizing a network appliance communicating over the IP network.", "[0050] It is another object and feature of the subject invention to provide an audio monitor or intercom between one or more network appliances and one or more monitor system using voice-over-IP (VOIP).", "[0051] It is another object and feature of the subject invention to provide an audio monitor or intercom between two or more network appliances utilizing VOIP.", "[0052] It is another object and feature of the subject invention to provide archival storage of VOIP audio information for later playback.", "[0053] It is another object and feature of the subject invention to provide a network appliance with video and/or audio capability with muted camera video and/or muted microphone audio capability in a room for privacy.", "[0054] It is another object and feature of the subject invention to provide a network appliance device that has an open camera and/or microphone when panic button is pushed.", "[0055] It is another object and feature of the subject invention to provide “intercom”", "and “emergency”", "buttons on a panic button.", "[0056] It is another object and feature of the subject invention to provide panic button initiated actions, such as: [0057] Intercom functions to and from room over IP.", "[0058] Logging of all intercom calls.", "[0059] Emergency notification to wired guard stations over IP.", "[0060] Emergency notification to wireless guard stations over IP.", "[0061] Push-To-Talk (or voice activation) response from guard or administrator.", "[0062] Display on room display stating identity of the responding party.", "[0063] Flashing location icon on map for intercom or emergency.", "[0064] Pop-up name of person pushing panic button.", "[0065] Pop-up location of person pushing panic button.", "[0066] Pop-up name of room where emergency is taking place.", "[0067] Logging of all panic button pushes, by whom, time, location, and the like.", "[0068] Logging of all responses, by whom, time, and the like.", "[0069] Recording of all emergency audio/video on server or appliance.", "[0070] For emergency calls, automatic call list: i.e., if first guard does not respond, go to next, go to administration.", "[0071] For emergency calls, have a party line: i.e., call all stations, all can respond asynchronously.", "[0072] On party line, all stations display the name of any speaker doing a push-to-talk (or voice activation) operation, with workstations having a pop-up display and wall appliance display shows instead of time.", "[0073] A software priority is established for the responding push to talk (or voice activation).", "Automatic notification priority based upon location, nearest, first, and so on.", "[0074] It is another object and feature of the subject invention to provide a workstation-to-workstation intercom utilizing VOIP.", "[0075] It is another object and feature of the subject invention to provide push-to-talk or voice activated control of audio from two or more stations on a group session at one time.", "[0076] It is another object and feature of the subject invention to provide an audio/video intercom from workstation-to-workstation utilizing VOIP.", "[0077] It is another object and feature of the subject invention to provide map-based dialing to workstations or network appliances.", "[0078] It is another object and feature of the subject invention to provide menu-based dialing to workstations or network appliances.", "[0079] It is another object and feature of the subject invention to provide IP video to and from network appliances.", "[0080] It is another object and feature of the subject invention to provide logging of all calls.", "[0081] It is another object and feature of the subject invention to provide logging of all calls with caller and/or called station ID's.", "[0082] It is another object and feature of the subject invention to provide logging of all calls with time stamps for time of calling and answering.", "[0083] It is another object and feature of the subject invention to provide logging of all calls by recording actual audio on the server.", "[0084] It is another object and feature of the subject invention to provide calls to guard stations and standard PC workstations.", "[0085] It is another object and feature of the subject invention to provide calls to administrative stations.", "[0086] It is another object and feature of the subject invention to provide calls from any workstation to any other workstation.", "[0087] It is another object and feature of the subject invention to provide other voice interfaces, such as: [0088] Calls patched into POTS telephone calls from the “outside”", "through a gateway network appliance device.", "[0089] Calls on internal PBX through a gateway network appliance device.", "[0090] Multimedia network appliances can be patched into VOIP telephone calls such as from the Internet, VOIP phone systems and the like.", "Incoming calls are automatically distributed.", "[0091] Outgoing calls by automatic priority, such as guard station first, if no answer, the police department over POTS.", "[0092] Outgoing calls by speed dialing.", "It is another object and feature of the subject invention to provide access control, such as: [0093] Access granted or denied flashing on map.", "[0094] Automatic camera switching based on any access attempt.", "[0095] Automatic camera switching on access denied only.", "[0096] Mode for manual guard confirmation for all accesses.", "[0097] Access network appliance powered over Cat-5 wiring.", "[0098] Access network appliance controlled over IP wiring.", "[0099] Access control of a network appliance decided by server, or by internal tables.", "[0100] Access network appliance has internal access allowance tables set over IP wiring.", "[0101] Access network appliance uses internal tables if server is down.", "[0102] Access network appliance always uses internal tables (to save bandwidth).", "[0103] Access network appliance is has encryption.", "[0104] Access network appliance has contact outputs.", "[0105] Access network appliance has optional wireless badge reader.", "[0106] Access network appliance has optional swipe badge reader.", "[0107] Access network appliance has optional fingerprint reader.", "[0108] Access network appliance has optional retina scanner.", "[0109] Access network appliance has link to personal geo-locator such that if authorized person is in close proximity door opens.", "[0110] Access network appliance opens under local control.", "[0111] Access network appliance opens under server control.", "[0112] Access network appliance has tamper detectors reporting over IP.", "[0113] Access network appliance sends all activity to server for logging.", "[0114] Access network appliance has local memory for logging all activity.", "[0115] Access network appliance can send local memory content to server for logging.", "[0116] Server can request access network appliance data for logging.", "[0117] Access network appliance is configured over IP.", "[0118] Access network appliance has HTML server for setup and monitoring.", "[0119] Access network appliance supports friendly names, such as “East Outside Door.”", "[0120] Access network appliance has password protection.", "[0121] Access network appliance has encrypted communications to and/or from.", "[0122] Access network appliance can communicate over wired LAN (example, cat-5).", "[0123] Access network appliance can communicate over wireless LAN (example IEEE 802.11B).", "[0124] Other objects and features will be readily apparent from the accompanying drawings and detailed description.", "BRIEF DESCRIPTION OF THE DRAWINGS [0125] [0125 ]FIG. 1 is a perspective view of a room network appliance module in accordance with the subject invention.", "[0126] [0126 ]FIG. 2 depicts an overall block-diagram view of a simple implementation of a wall network appliance of the typed shown in FIG. 1. [0127] [0127 ]FIG. 3 illustrates a network-supported circuit for communicating a time standard to a network appliance for use in event logging or event execution by a network appliance via a local network.", "[0128] [0128 ]FIG. 4 shows a configuration including a network hub embedded into the security network appliance.", "[0129] [0129 ]FIG. 5 shows a configuration wherein a room network appliance includes wireless networking technologies.", "[0130] [0130 ]FIG. 6 illustrates the utility of the room network appliance as configures as an integrated multimedia sensor for a plurality safety-related sensors commonly employed in such a facility.", "[0131] [0131 ]FIG. 6A is a wireless version of network appliance shown in FIG. 6. [0132] [0132 ]FIG. 7 depicts a room network appliance as a gathering point for room environmental data.", "[0133] [0133 ]FIG. 7A is a wireless version of the network appliance shown in FIG. 7. [0134] [0134 ]FIG. 8 illustrates a network appliance enhancement including a video camera, digitizer, motion video compressor, still-frame video compressor, infrared illuminator for dark operation, audio sensor, digitizer, and audio compressor.", "[0135] [0135 ]FIG. 8A is a wireless version of the network appliance shown in FIG. 8. [0136] [0136 ]FIG. 9 illustrates a room network appliance with an alternative alarm source wherein a wireless “panic button”", "alarm device may activate the system.", "[0137] [0137 ]FIG. 9A is a wireless version of the room network appliance shown in FIG. 9. [0138] [0138 ]FIG. 10 illustrates one method power insertion technique utilizing the LAN data link incorporated in the system of the invention to power a wired network appliance.", "[0139] [0139 ]FIG. 11 depicts an alternative embodiment including an alternate power insertion technique whereby DC power conveyed along signal pairs of the cable, in common-mode, in order to power a wired network appliance.", "[0140] [0140 ]FIG. 12 depicts a motion detector sensor network appliance with an IP network interface and power receiver.", "[0141] [0141 ]FIG. 12A is a wireless version of the network appliance shown in FIG. 12.", "[0142] [0142 ]FIG. 13 depicts a networked smoke detector network appliance using the network interface of FIG. 12.", "[0143] [0143 ]FIG. 13A is a wireless version of the network appliance shown in FIG. 13.", "[0144] [0144 ]FIG. 14 depicts a conventional ‘Pull Handle’ commonly used in institutional fire alarm systems as adapted for incorporation in the networked appliance of the subject invention.", "[0145] [0145 ]FIG. 14A is a wireless version of the network appliance shown in FIG. 14.", "[0146] [0146 ]FIG. 15 depicts a contact-closure interface, as is commonly used for door or window sensors in alarm systems as adapted as a networked appliance of the subject invention.", "[0147] [0147 ]FIG. 15A is a wireless version of the network appliance shown in FIG. 15.", "[0148] [0148 ]FIG. 16 depicts a heat sensor network appliance.", "[0149] [0149 ]FIG. 16A is a wireless version of the network appliance shown in FIG. 16.", "[0150] [0150 ]FIG. 17 depicts a glass breakage sensor network appliance.", "[0151] [0151 ]FIG. 17A is a wireless version of the network appliance shown in FIG. 17.", "[0152] [0152 ]FIG. 18 depicts an alarm siren network appliance.", "[0153] [0153 ]FIG. 18A is a wireless version of the network appliance shown in FIG. 18.", "[0154] [0154 ]FIG. 19 depicts a strobe light network appliance.", "[0155] [0155 ]FIG. 19A is a wireless version of the network appliance shown in FIG. 19.", "[0156] [0156 ]FIG. 20 depicts a thermostat/humidistat network appliance.", "[0157] [0157 ]FIG. 20A is a wireless version of the network appliance shown in FIG. 20A.", "[0158] [0158 ]FIG. 21 depicts a general-purpose control panel network appliance.", "[0159] [0159 ]FIG. 21A is a wireless version of the network appliance shown in FIG. 21.", "[0160] [0160 ]FIG. 22 depicts a simple control switch network appliance.", "[0161] [0161 ]FIG. 22A is a wireless version of the network appliance shown in FIG. 22.", "[0162] [0162 ]FIG. 23 depicts an indicator light panel network appliance.", "[0163] [0163 ]FIG. 23A is a wireless version of the network appliance shown in FIG. 23.", "[0164] [0164 ]FIG. 24 depicts a networked analog user interface control network appliance, such as may be used to control room lights, temperature, fan speed, louver blind position, loudspeaker volume, and the like.", "[0165] [0165 ]FIG. 24A is a wireless version of the network appliance shown in FIG. 24.", "[0166] [0166 ]FIG. 25 depicts a loudspeaker network appliance.", "[0167] [0167 ]FIG. 25A is a wireless version of the network appliance shown in FIG. 25.", "[0168] [0168 ]FIG. 26 depicts a control panel network appliance with indicator lights.", "[0169] [0169 ]FIG. 26A is a wireless version of the network appliance shown in FIG. 26.", "[0170] [0170 ]FIG. 27 depicts a power outlet network appliance.", "[0171] [0171 ]FIG. 27A is a wireless version of the network appliance shown in FIG. 27.", "[0172] [0172 ]FIG. 28 illustrates an AC socket as expanded into a network-controlled AC power strip network appliance.", "[0173] [0173 ]FIG. 28A is a wireless version of the network appliance shown in FIG. 28.", "[0174] [0174 ]FIG. 29 depicts a telephone interface/dialer network appliance.", "[0175] [0175 ]FIG. 29A is a wireless version of the network appliance shown in FIG. 29.", "[0176] [0176 ]FIG. 30 depicts a lighting fixture network appliance controlled over a network.", "[0177] [0177 ]FIG. 30A is a wireless version of the network appliance shown in FIG. 30.", "[0178] [0178 ]FIG. 31 depicts an analog wall clock network appliance controlled over the IP network.", "[0179] [0179 ]FIG. 31A is a wireless version of the network appliance shown in FIG. 31.", "[0180] [0180 ]FIG. 32 depicts an alternative embodiment of the network appliance of FIG. 31, wherein a digital display replaces the stepper motor, gearbox, hands and shaft encoder.", "[0181] [0181 ]FIG. 32A is a wireless version of the network appliance shown in FIG. 32.", "[0182] [0182 ]FIG. 33 depicts a self-contained magnetic strip reader network appliance, containing a reader as is commonly used in ATM machines, gas pumps, and point-of-sale cash registers.", "[0183] [0183 ]FIG. 33A is a wireless version of the network shown in FIG. 33.", "[0184] [0184 ]FIG. 34 depicts a proximity card reader network appliance.", "[0185] [0185 ]FIG. 34A is a wireless version of the network appliance shown in FIG. 34.", "[0186] [0186 ]FIG. 35 depicts an electronic door strike controller network appliance shown controlling a standard elector-mechanical door strike.", "[0187] [0187 ]FIG. 35A is a wireless version of the network appliance shown in FIG. 35.", "[0188] [0188 ]FIG. 35B is a self-contained electronic door strike network appliance with an integrated IP network interface and electro-mechanical door strike.", "[0189] [0189 ]FIG. 35C is a wireless version of the network appliance shown in FIG. 35B.", "[0190] [0190 ]FIG. 36 depicts a combination security controller network appliance showing as it is utilized to control an electronic door strike, a door contact switch, a keypad entry system, and a secondary identification component such as a magnetic stripe reader, a proximity sensor or retina reader, or the like.", "[0191] [0191 ]FIG. 36A is a wireless version of the network appliance shown in a FIG. 36.", "[0192] [0192 ]FIG. 37 depicts a combination security controller network appliance controlling an electric door strike, and sensing door contacts and a proximity sensor FIG. 37A is a wireless version of the network appliance shown in FIG. 37.", "[0193] [0193 ]FIG. 37B is an electronic strike network appliance with external contact inputs.", "[0194] [0194 ]FIG. 37C is a wireless version of the network appliance shown in FIG. 37B.", "[0195] [0195 ]FIG. 38 depicts a combination network appliance that is controlling an electric door strike and sensing door contacts and a magnetic stripe reader.", "FIG. 38A is a wireless version of the network appliance show in FIG. 38.", "[0196] [0196 ]FIG. 39 depicts a keypad entry network appliance with auxiliary electric strike and door contacts.", "[0197] [0197 ]FIG. 39A is a wireless version of the network appliance shown in FIG. 39.", "[0198] [0198 ]FIG. 40 shows a wireless proximity sensor network appliance.", "[0199] [0199 ]FIG. 39A depicts the circuit diagram for the system of FIG. 39 [0200] [0200 ]FIG. 39B depicts the circuit diagram for a wireless version of the system of FIG. 39.", "[0201] [0201 ]FIG. 40 shows a system similar to the system shown in FIG. 39 with the addition of an exit sign.", "[0202] [0202 ]FIG. 40A depicts the circuit diagram for the system of FIG. 40.", "[0203] [0203 ]FIG. 41 depicts a wired universal interface-pull handle/strobe system.", "[0204] [0204 ]FIG. 41A is a wireless version of the system shown in FIG. 41.", "[0205] [0205 ]FIG. 42 depicts a wired pull handle system.", "[0206] [0206 ]FIG. 42A is a wireless version of the system shown in FIG. 42.", "[0207] [0207 ]FIG. 43 depicts a wired exit device.", "[0208] [0208 ]FIG. 43A is a wireless version of the system shown in FIG. 43.", "[0209] [0209 ]FIG. 44 depicts a wired keypad mortise lock.", "[0210] [0210 ]FIG. 44A is a wireless version of the system shown in FIG. 44.", "[0211] [0211 ]FIG. 45 depicts a wired magnetic card stripe swipe reader mortise lock.", "[0212] [0212 ]FIG. 45A is a wireless version of the system of FIG. 45.", "[0213] [0213 ]FIG. 46 depicts a wired proximity card reader mortise lock.", "[0214] [0214 ]FIG. 46A is a wireless version of the system of FIG. 46.", "[0215] [0215 ]FIG. 47 is a control center system and diagram for connecting various sensors to the system.", "[0216] [0216 ]FIG. 47A is a wireless version of the system of FIG. 47.", "[0217] [0217 ]FIGS. 48 and 49 depict multiple universal interface applications.", "[0218] [0218 ]FIG. 50 is a block diagram of the multiple appliance security system in accordance with the invention.", "[0219] [0219 ]FIGS. 51 and 51A-* comprise a full schematic of the system in accordance with the block diagram of FIG. 50.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0220] [0220 ]FIG. 1 depicts an overall view of the appliance 5 of the subject invention.", "The appliance contains a variety of devices that are commonplace or useful in educational, institutional, or office environments, including: [0221] A conventional clock display 25 , operable to display other information as needed such as temperature, humidity, alert messages, etc.", "[0222] A microphone 35 , to detect local ambient sounds in the room and send them to a remote location and, optionally, to support acoustic event detection of gunshots and the like, [0223] A loudspeaker 20 , to allow remote supervisory personnel to communicate with room occupants, [0224] A beacon transmitter 30 , which emits coded infrared, RF, or ultrasonic energy into the room for the purpose of activating personnel locator devices therein, [0225] A beacon receiver also 30 , which detects coded infrared, RF, or ultrasonic energy emitted by locator devices within the room, [0226] A camera 15 , to view live or still scenes in the room and send them to a remote location, [0227] A standard RJ-45 or equivalent connector 40 for connecting to a facility Network.", "[0228] An antenna 10 may be provided for supporting a wireless connection, as will be explained therein.", "[0229] [0229 ]FIG. 2 depicts an overall block-diagram view of a simple implementation, such as may be used in an educational setting.", "In this implementation, the appliance only supports a clock display 65 , a loudspeaker 45 , and a microphone 55 , to support the ordinary clock and intercom commonly found in schoolrooms.", "As shown, a digital-to-analog converter 50 and an analog-to-digital converter 60 are used as required for conditioning signals input to and output from the signal processor 70 .", "The system processor is connected to a network interface 80 , and/or as desired a wireless interface 85 .", "The wireless interface 85 is in wireless communication with a wireless access point 87 for providing a gateway to the network 90 .", "[0230] The device is connected to a local-area-network, such as the commonplace 10Base-T, via the network interface.", "10Base-T networks commonly employ twisted-pair wiring between hubs and connected devices;", "an alternative implementation may use IEEE 802.11 or equivalent wireless connections.", "In either case, the network interface passes information to and from the appliance's processor.", "The processor controls the clock display.", "Ambient sounds picked up by the microphone are digitized, compressed, and transmitted to the network via the A/D converter, signal processor, system processor, and network interface.", "A variety of compression methods and communication protocols may be employed;", "in the preferred embodiment the audio is compressed using MP3 and sent to the network using the RTP and TCP/IP protocols.", "Similarly, compressed audio from the network may be received, de-multiplexed, decoded, and played back via the network interface, system processor, signal processor, and D/A converter.", "[0231] As depicted in FIG. 3, the clock may be set from a time server 110 connected to the local network 115 .", "A variety of network-based time-transfer methods exist, the most popular and convenient is Network Time Protocol (NTP), a protocol used in conjunction with local-area networks or the Internet.", "Using NTP, the time server and the client (in this case, the appliance) exchange time messages, and determine a statistical value for network delay, which is then factored out.", "Accuracies on the order of 1 millisecond are possible on a local network.", "The timeserver may be set manually, or may optionally be set using a commercially available WWV time receiver 100 or GPS time receiver 105 .", "As an alternative, the local time server may set itself to an internet-based master timeserver, such as provided by NIST or the U.S. Naval Observatory (USNO) as indicated by the network timeserver 125 , via the network 120 .", "Various security appliances including the security circuits 94 may be incorporated in the circuit via the network interface 95 .", "[0232] A useful refinement of the system is depicted in FIG. 4. As there shown, the appliance processor 130 is connected to an embedded network hub 140 via a network interface 135 .", "Typically, a 10Base-T hub, or equivalent, is embedded into the appliance.", "[0233] This allows other computers 150 , 155 , printers 145 , or other networked devices (via network 160 ) to share the existing connection from the room to the facility's local area network.", "By way of an example, remote workstation 157 may be supported in this manner.", "An archival server 161 is accessible over the network 160 .", "[0234] The local area network hub may also include wireless networking technologies, such as the IEEE 802.11, as depicted in FIG. 5. In this enhancement a wireless LAN access point 180 and an antenna 175 is provided at the appliance, permitting communication with various wireless remote components or systems such as the printer 195 supported by the wireless adapter 205 and antenna 200 , the wireless desktop PC 215 and antenna 210 , the wireless laptop 225 or other portable device and antenna 220 .", "[0235] [0235 ]FIG. 6 illustrates the utility of the room appliance as a collection point for safety-related sensors such as, by way of example, the microwave motion detector 230 , the infrared motion detector 235 , the smoke detector 240 , and the carbon monoxide detector 250 , commonly employed in such a facility.", "The processor 265 collects data from the various sensors in the room.", "Such inputs are often simple contact closure inputs.", "When activated, the appliance alerts a security monitoring station via the local network or via a wide-area network 275 through the network interface 270 .", "The security station may then summon the appropriate help, such as police, fire, ambulance, or other services as needed.", "Also, the system processor when so activated may generate an appropriate local warning sound using the D/A converter 260 and the loudspeaker 255 .", "Appropriate sounds might be a fire horn, alarm bell, klaxon, or the like.", "The warning sounds may be generated from stored sounds in the processor's memory, or may be generated by the facility security system and transmitted to the room appliance via the intervening network.", "As shown, various remote stations such as a logging server or archive server 161 , a security monitoring station 280 and other systems such as by way of example the environmental monitoring controller 281 .", "[0236] [0236 ]FIG. 6A is a wireless version of the system of FIG. 6. In this enhancement a wireless interface 283 is provided for communicating with a wireless access point 287 to provide a link to the network 275 .", "Also in this embodiment a power supply 289 and a converter 291 is provided to power the appliance system.", "In the wired version the network cabling is used to provide power.", "[0237] [0237 ]FIG. 7 depicts the room appliance as a gathering point for room environmental data, as may be used in controlling an HVAC system.", "Various environmental control sensors, such as a relative humidity sensor 285 , temperature sensor 290 , or thermostat panel 295 , may connect to the facility HVAC controller 315 via the room appliance processor 265 and network 310 .", "Other critical monitoring systems such as, by way of example, the fire alarm controller 316 , may be interconnected to this subsystem via the network.", "The wireless version is shown in FIG. 7A.", "[0238] [0238 ]FIG. 8 illustrates an enhancement to the basic appliance system, wherein a video camera 325 , digitizer 330 , motion video buffer 335 and compressor 340 and, optionally, a still-frame video buffer 345 and compressor 350 is added.", "An illuminator 320 for low light conditions may also be supplied.", "When activated, the camera captures local scenes, and transmits them to a monitoring station(s) 390 on the local network or-wide-area network using suitable compression methods such as MPEG or JPEG, via the network comprising the multiplexer 355 , the system or appliance processor 375 and a network interface 380 whereby communication via the network 385 is supported.", "Simultaneously, the microphone 360 may be included to receive local sounds, digitize them at converter 365 , compress them at compressor 370 , and send them to the same destinations.", "Activation of the camera and microphone may be accomplished locally via one or more of the attached sensors, or remotely via the network from a monitoring station.", "If the ambient illumination is insufficient for viewing via the camera, an illuminator may be enabled by command from the appliance's processor or by command from the remote station.", "The illuminator may be visible light or infrared, as desired.", "A wireless version is shown in FIG. 8A with an independent power supply 289 , converter 291 and wireless access point 287 is provided as previously described.", "[0239] An alternative alarm source is depicted in FIG. 9, wherein a wireless “panic button”", "alarm device 440 may activate the system using the wireless transmitter 445 and receiver 450 , 455 .", "As shown, the wireless alarm has an RF receiver 455 and transmitter 465 , controlled by the T/R switch 460 , a device ID memory 475 , and a pushbutton switch 480 .", "A process controller 470 is also provided.", "During normal usage, the room appliance 485 periodically transmits a code representing its location.", "The personal alarm 440 receives and stores this location code.", "When the alarm is activated by pressing the switch 480 , the alarm transmits its device ID and the room ID information to the appliance 440 .", "This then activates the appliance, enabling the camera and microphone, and alerts the central monitoring station via the intervening network.", "As shown, the appliance 440 in this configuration includes a compatible RF receiver 400 , T/R switch 405 , RF transmitter 410 with antenna 395 .", "The appliance processor 425 and network interface 430 communicate with the network 435 as previously described.", "An encoder 420 may be provided as necessary.", "FIG. 9A shows the same system with wireless network interfacing as previously described.", "[0240] [0240 ]FIGS. 10 and 11 depict a standardized method and apparatus for monitoring, controlling, and powering a variety of network-based appliances, which are subsequently described.", "This is advantageous when the network-based may be located in an area where conventional AC-operated power is not easily accessible.", "Referring to FIG. 10, a conventional LAN data link is depicted.", "The hub's physical-layer interface 800 connects to twisted-pairs 815 and 820 via transformers 805 and 810 .", "The remote network device's physical-layer interface 830 connects to the same twisted pairs 815 and 820 via transformers 825 and 830 , thus effectuating a conventional LAN connection.", "Twisted-pair cable typically used in LAN's generally contains 4 pairs, who of which are unused in this example.", "Accordingly, one or both of the unused twisted-pairs 855 and 865 are employed to convey operating power to the remote device.", "A power source 840 is disposed at the centralized hub or switch.", "The power source is preferably a voltage source, and preferably a DC source of moderately high voltage.", "Typical voltage levels may run in the 30 to 60 Volt range.", "Current sensor 845 senses the DC current consumed by the remote device, and may cause current limiter 850 to reduce or eliminate any current supplied to the remote device, in the case of a fault in the wiring or in the remote device.", "At the remote device, power is extracted and regulated by regulator 860 , preferably a switched-mode down-converter of high efficiency.", "[0241] [0241 ]FIG. 11 depicts a variation of the same method, wherein the DC power is conveyed along the signal pairs of the cable 855 , 865 , in common-mode.", "In this example, transformers 805 , 810 , 825 , and 830 are center-tapped, and the power is applied to the center taps of transformers 805 and 810 .", "Said power is extracted from the center taps of transformers 825 and 830 at the remote device.", "As before, power is supplied by source 840 , and is monitored and protected by current sensor 845 and limiter 850 .", "At the remote end, power extracted from the center taps of transformers 825 and 830 is appropriately regulated by regulator 860 .", "[0242] The network interface, common to all subsequent network devices, here represented as the motion sensor 525 , is depicted in FIG. 12.", "The device attaches to the network using RJ-45 connector 520 .", "An Ethernet interface 515 handles the physical-layer connection to the Ethernet network.", "The required DC operating power, as supplied over the network wiring, passed through RJ-45 connector 520 to the Ethernet Line-Power Interface 510 .", "This interface extracts the DC power provided by the network, and provides filtering and regulation as necessary to provide the DC operating voltages required by the device via line 505 .", "The power provided by the network will typically be at a relatively high DC voltage for the sake of transmission efficiency.", "The Line-Power interface will therefore typically contain one or more regulators to reduce the line-supplied DC voltage to an appropriate value such as the standard 3.3 VDC or 5 VDC.", "An IP controller 500 is provided.", "[0243] An additional benefit of the described configuration is that all sensors or appliances are intelligent due to the presence of the preprogrammed IP controller.", "This allows a centralized system monitoring station to automatically detect and configure the individual sensors or appliances.", "For example, a device may ‘announce’ itself immediately upon installation, thus becoming automatically recognized and monitored by the centralized monitoring station.", "Also, relevant operating parameters of the device may be measured or controlled remotely.", "An example might be a glass breakage detector with a history of false alarms;", "the sensor's sensitivity may be reduced from the centralized monitoring station via the network.", "FIG. 12A shows a wireless version of the system depicted in FIG. 12.", "In this enhancement a wireless interface card 526 and receiver/transmitter 528 is provided at the device, for defining the wireless interface 380 that operates as previously described.", "[0244] [0244 ]FIGS. 13 through 34A depict a variety of additional sensors and appliances that may be attached to the described network.", "All these described devices share a common network interface, allowing any such device to be added to the network as desired.", "Moreover, all such devices are configured to derive their operating DC power from the network, rather than from locally supplied power.", "[0245] [0245 ]FIG. 13 depicts a networked smoke detector, using the same standardized network interface of FIG. 12.", "The device may also contain a heat sensor, to increase the accuracy of detecting a fire.", "The smoke and heat sensors 530 and 535 pass their data to the IP controller 500 , which generates and transmits a predefined message to the network.", "Note that the heat sensor may pass an actual numerical value for temperature to the network if desired, rather than a simple 1-bit indication that a temperature threshold has been exceeded.", "FIG. 13A is the wireless version and corresponds to the circuit shown in FIG. 12A.", "[0246] [0246 ]FIG. 14 depicts a conventional ‘Pull Handle’ commonly used in institutional fire alarm systems.", "In this case, the input to the IP controller 500 is a simple 1-bit input from the pull handle switch 540 .", "Again, the device sends a predefined IP message to the network and system monitoring station upon activation.", "FIG. 14 is the wireless version.", "[0247] [0247 ]FIG. 15 depicts a simple contact-closure interface, as is commonly used for door or window sensors in alarm systems.", "The sensors often contain a magnet in one module, and a magnetic reed switch in the other module.", "In this implementation, the contact closure thus effectuated by the reed switch 545 becomes input bit into the IP controller 500 .", "In response to a change in switch status, the controller 500 generates and transmits a predefined IP message via the Ethernet interface to the network and associated monitoring apparatus.", "FIG. 15A is the wireless version.", "[0248] [0248 ]FIG. 16 depicts a networked heat sensor.", "The sensor 550 may produce a simple one-bit ‘threshold crossed’ indication to the controller 500 , or may pass a variable representing actual sensed temperature.", "In either case, the IP controller 500 generates and transmits a predefined IP message to the network and associated monitoring apparatus.", "As an additional refinement, the device may be programmed to accept configuration commands from the networked monitoring apparatus.", "Such commands may, for example, change the sensor's trip point or temporarily suspend the transmission of messages.", "FIG. 16A is the wireless version.", "[0249] A networked glass breakage sensor is depicted in FIG. 17.", "Sensor 555 produces an output indicative of breaking glass to the IP controller 500 , which generates a predefined IP message and transmits said message to the network.", "The sensor's output may, if necessary be processed or analyzed by controller 500 in the case of a simple microphone or vibration sensor.", "The device may additionally be configured to respond to incoming control and configuration messages from the network, such as commands to change the sensor's sensitivity or to temporarily disable the device.", "FIG. 17 is the wireless version.", "[0250] [0250 ]FIGS. 18 and 19 depict a networked alarm siren and strobe light respectively.", "The IP controller 500 receives IP messages from the network and controls the alarm 560 or strobe light 565 respectively.", "Network messages may be used to turn the alarm or strobe on or off, or may control other characteristics of the device such as volume, flash rate, etc.", "The IP controller may also send status messages to the network, either in response to inquiries from control devices or at regular intervals.", "FIGS. 18A and 19A are the wireless versions, respectively.", "[0251] [0251 ]FIG. 20 depicts a networked thermostat or humidistat, or both combined.", "The temperature sensor 570 and/or humidity sensor 575 produce signals indicative of local temperature and/or humidity.", "As before, IP controller 500 generates and transmits predefined messages to the network representing the current values of temperature and/or humidity.", "In addition, switches 580 and 585 allow a user to increase or decrease the desired temperature setting.", "Contact closures produced by switches 580 or 585 are detected by IP controller 500 and transmitted via IP messages to a monitoring and/or control device disposed on the network.", "In addition, display 590 displays the current value of the local temperature and/or temperature setting.", "The temperature displayed may be generated locally by the controller 500 or may be commanded by a networked monitoring and control device via IP messaging.", "FIG. 20A is the wireless version of the thermostat/humidistat network appliance.", "[0252] A general-purpose control panel network appliance is depicted in FIG. 21.", "This is a highly flexible device that can be used for several multimedia monitoring functions, as well as many control functions.", "For example, the control network appliance can be utilized as a conventional type control keypad for alarm system functions.", "It also could be utilized for lighting control, HVAC control, pump control, fan control, volume control, and other facility management founctions.", "A keypad 595 and display 600 are connected to the IP controller 500 .", "The controller 500 detects and interprets keystrokes on keypad 595 , and generates appropriate IP messages for transmission over the intervening network to a networked monitoring and control station.", "Similarly, a networked monitoring and control station may generate messages to be displayed on the control panel's display 600 .", "Said messages are transmitted from the monitoring and control station via the IP network to the controller 500 , which causes the appropriate message to be displayed.", "Speaker 601 is provided for audible indications of keypad depression, status, alarms and for streaming of audio streams.", "[0253] [0253 ]FIG. 21A is the wireless version of the control panel network appliance.", "[0254] [0254 ]FIG. 22 depicts a simple control switch network appliance.", "The switch 605 may be a toggle, rocker, or push-button switch as appropriate.", "The status of switch 605 is detected by IP controller 500 , which generates and transmits an appropriate message over the IP network to a networked monitoring and control station.", "The appliance may be configured to generate “on”", "and “off”", "signals for controlling a two state device, or with a center return momentary switch, can generate streams of “up”", "and “down”", "signal steams relating to the length of time that the button is held for “analog”", "controlling of devices.", "[0255] [0255 ]FIG. 22A is the wireless version of the control switch network appliance.", "[0256] An indicator light network appliance is depicted in FIG. 23.", "IP controller 500 receives messages from a networked monitoring and control station, and thereupon causes the appropriate lamp or lamps in light array 610 to be illuminated or extinguished.", "FIG. 23A is the wireless version of the indicator light network appliance.", "[0257] [0257 ]FIG. 24 depicts an analog control device network appliance, such as may be used to control room lights, temperature, loudspeaker volume, fan speed and the like.", "IP controller 500 receives input from potentiometer 615 or shaft encoder 620 , and thereupon generates appropriate IP messages and transmits them via the intervening IP network to a networked monitoring and control station.", "[0258] [0258 ]FIG. 24A is the wireless analog control device network appliance.", "[0259] A networked loudspeaker appliance is depicted in FIG. 25.", "In the preferred embodiment, the device receives a stream of data representing audio from the IP network.", "IP controller 500 passes this data to processor 625 , which decodes the data stream and generates an appropriate analog signal for reproduction via loudspeaker 630 .", "Control signals such as speaker amplifier gain, tone controls and the like can be sent to the loudspeaker appliance via the network.", "[0260] [0260 ]FIG. 25A is the wireless version of the loudspeaker network appliance.", "[0261] A control panel network appliance, with indicator lights is depicted in FIG. 26.", "Switches 635 and 640 cause the IP controller 500 to generate and transmit IP messages to a networked monitoring and control station.", "Additionally, a networked monitoring and control station may generate appropriate IP messages to control the status of lamps 645 , 650 , and 655 via the intervening network and IP controller 500 .", "FIG. 26A is the wireless version of the control panel network appliance.", "[0262] A networked power outlet is depicted in FIG. 27.", "In this device, the IP controller 500 controls the status of an AC power switch 670 in response to received IP messages from a networked monitoring and control station.", "The networked monitoring and control station may thereby turn an AC-powered appliance ON or OFF via networked IP messages.", "Alternatively, power switch 670 may be replaced with a dimmer module, to allow dimming of a lamp from the networked monitoring and control station.", "Additionally, an RJ-45 socket 665 may be installed on the device, to provide a local user with an Ethernet connection into the network.", "Effectively this allows the power control module to act as a network hub as well.", "Since the network connection to the network is already in use by the system controller 500 , when another network connection port is needed such as 665 , it is necessary to implement a simple three-port network hub 660 between the network physical-layer interface 515 and the RJ-45 connector to the network 520 .", "[0263] [0263 ]FIG. 27A is the wireless version.", "In the preferred embodiment the power for the network interface and control circuits are taken from the incoming AC power.", "[0264] In FIG. 28, the network-controlled AC socket is expanded into a network-controlled AC power strip appliance.", "As previously described in FIG. 27, the IP controller 500 controls a switch or dimmer 670 in response to IP messages received via the network from a monitoring and control station.", "In this embodiment, multiple AC sockets 675 are provided.", "In addition, a circuit breaker 680 protects the device from overload.", "Surge protectors can also be implemented.", "Additional circuits can can read the status of the power strip, such as the state of the circuit breaker, input voltage and the status of the surge protector.", "The current load of the power strip can also be measured.", "This allows for extensive “remote management”", "of the power strip over the network such as from a network operations center (NOC).", "Multiple power controllers, such as 670 , can be implemted such as one for each plug.", "This allows independent control of each plug.", "This could allow remote power cycling of a bank of network computers, for example, or would allow control of multiple temporary lighting circuits, stage lights, etc.", "Although the power strip network appliance can be powered by the incoming AC power line, if the power is not present the status of the strip could not be read.", "The network and control circuits can,however, be powered by the network connection as is described elsewhere in this application.", "This would allow the network devices to read the managed power strip status even if the incoming AC power is not available or the circuit breaker is tripped.", "[0265] [0265 ]FIG. 28A is the wireless version of the power strip network appliance.", "[0266] [0266 ]FIG. 29 depicts a network-controlled telephone dialer/interface, preferably housed in a standard telephone wall socket.", "A standard POTS telephone line or telephone is plugged into the telephone line 700 via RJ-11 socket 705 .", "VOIP data can then be transferred from the phone line to the network, and from the network to the telephone line.", "If a central office (CO) line or private branch exchange (PBX) line is plugged into the RJ-11 jack, the RJ-11 interface is configured as a virtual telephone instrument.", "If a POTS telephone instrument is plugged into the RJ-11 socket, the RJ-11 interface is configured as a virtual telephone line.", "When configured as a virtual instrument, the IP controller 500 , in response to commands received from the IP network, energizes relay 695 , thus seizing telephone line 700 .", "The IP controller 500 thereupon, in response to IP commands received via the IP network, causes DTMF generator 685 to produce the desired DTMF tones on telephone line 700 via line transformer 690 .", "The interface also monitors the line to detect ringing and to detect caller-ID (CLID) data, and communicates that date via the LAN, then awaits for instuction to seize the telephone line.", "When configured as a virtual line, the network appliance supplies talk battery to the POT S telephone to power the telephone, the tone dial, and to detect off-hook conditions.", "It also generates a ring voltage to ring the POTS telephone when instructed to do so from instructions received over the network.", "This device has several uses in the multimedia system.", "It can be used to provide an interface to emergency telephones that are in communication with monitor stations.", "It is also used to interface to the telephone line for dialing and signaling under the control of the event notification services as is described in my other patents/patent applications.", "It also can be used a stand-alone relay for a voice circuit between a pair if, or more, telephones, emulating an “order wire.”", "It also can be used as a bridge, providing a remote POTS telephone line via a LAN or WAN to another location for a POTS telephone instrument.", "[0267] [0267 ]FIG. 29A is the wireless version of the telephone dialer/interface network appliance.", "[0268] [0268 ]FIG. 30 depicts a lighting fixture network appliance controlled over the network.", "As in FIG. 27, IP controller 500 turns the light ON or OFF, or may dim the light, in response to IP messages received from a monitoring and control station via the network.", "The appliance can also monitor the status of the bulb and report over the network.", "This “managed bulb”", "can then be interrogated from a NOC, or a burned out bulb can generate an event that is notified to maintenance personnel for action by the notification services as described by my other patents/applications.", "[0269] [0269 ]FIG. 30A is the wireless version of the lighting fixture network appliance.", "[0270] [0270 ]FIG. 31 depicts an analog wall clock network appliance controlled by the IP network.", "IP controller- 500 maintains an accurate knowledge of local time through periodic synchronization with a network time standard via SNTP or other appropriate network-time protocols.", "IP controller 500 drives a stepper motor 720 , which drives hands 735 , 740 , and 745 via gear train 730 .", "Shaft encoder 725 provides shaft position feedback information to IP controller 500 , to allow the clock to be set after a power failure.", "The shaft encoder may be as simple as a one-bit indication that the hands are all in the 12:00 position.", "[0271] [0271 ]FIG. 31A is the wireless version of the analog wall clock network appliance.", "[0272] [0272 ]FIG. 32 depicts an alternative embodiment, the digital clock network appliance, wherein a digital display 735 and drive electronics replaces the stepper motor 720 , gearbox 730 , hands 735 , 740 , and 745 , and shaft encoder 725 .", "As before, IP controller 500 maintains accurate time via periodic synchronization over the IP network.", "[0273] [0273 ]FIG. 32A is the wireless version digital clock network appliance.", "[0274] [0274 ]FIG. 33 depicts a magnetic strip reader network appliance.", "The magnetic strip reader, as commonly used in ATM machines, gas pumps, and point-of-sale cash registers.", "Card reader 750 passes data extracted from the card to IP controller 500 , which thereupon transmits the card data to a device on the IP network for appropriate processing.", "The card data is preferentially encrypted by IP controller before transmission, to provide security.", "[0275] [0275 ]FIG. 33A is the wireless version magnetic strip reader network appliance.", "[0276] [0276 ]FIG. 34 depicts a proximity card reader network appliance.", "This incorporates a proximity ID card readers, as commonly used at door entrances.", "IP controller 500 receives data detected by badge sensor 755 , and passes an appropriate predefined IP message to a networked monitoring and control station.", "[0277] [0277 ]FIG. 34 depicts a proximity card reader network appliance.", "This incorporates a proximity ID card readers, as commonly used at door entrances.", "IP controller 500 receives data detected by badge sensor 755 , and passes an appropriate predefined IP message to a networked monitoring and control station.", "[0278] [0278 ]FIG. 34A is the wireless proximity card reader network appliance.", "[0279] It is an important feature of the subject invention that legacy sensors, alarms and devices may be connected to the multimedia network system without modification of the legacy devices, permitting signals generated by the legacy devices to be communicated via and managed by the system of the subject invention.", "FIGS. 35 - 38 are examples of security network appliances that provide such enhancements.", "An important component of this feature is a common interface permitting the communication of the signals generated by the legacy device to the network supporting the system of the subject invention.", "One common interface network appliance device 900 is shown in FIG. 35 and includes two terminals or connectors 901 , 902 for connecting the output wires 904 , 905 of a legacy device, here an electric door strike 906 , to the network.", "The network connection is made via a wire connected at the RJ-45 jack 908 .", "[0280] As shown in FIG. 35A, the legacy device can also be connected via wireless interface 910 .", "In this version, a power adapter 912 is provided for driving the interface 910 .", "A wireless transmitter/receiver card 914 is added to provide the wireless network connection.", "In the wired version, the connector wire connected to the RJ-45 jack 908 is ideally used to provide power.", "However, a separate power supply can be provided where desired.", "FIG. 35B shows an electric strike 906 with an RJ45 jack 908 .", "FIG. 35C is the wireless version.", "FIG. 34 depicts a proximity card reader network appliance.", "This incorporates a proximity ID card readers, as commonly used at door entrances.", "IP controller 500 receives data detected by badge sensor 755 , and passes an appropriate predefined IP message to a networked monitoring and control station.", "[0281] [0281 ]FIG. 34A is the wireless proximity card reader network appliance.", "[0282] It is an important feature of the subject invention that legacy sensors, alarms and devices may be connected to the multimedia network system without modification of the legacy devices, permitting signals generated by the legacy devices to be communicated via and managed by the system of the subject invention.", "FIGS. 35 - 38 are examples of security network appliances that provide such enhancements.", "An important component of this feature is a common interface permitting the communication of the signals generated by the legacy device to the network supporting the system of the subject invention.", "One common interface network appliance device 900 is shown in FIG. 35 and includes two terminals or connectors 901 , 902 for connecting the output wires 904 , 905 of a legacy device, here an electric door strike 906 , to the network.", "The network connection is made via a wire connected at the RJ-45 jack 908 .", "[0283] As shown in FIG. 35A, the legacy device can also be connected via wireless interface 910 .", "In this version, a power adapter 912 is provided for driving the interface 910 .", "A wireless transmitter/receiver card 914 is added to provide the wireless network connection.", "In the wired version, the connector wire connected to the RJ-45 jack 908 is ideally used to provide power.", "However, a separate power supply can be provided where desired.", "FIG. 35B shows an electric strike 906 with an RJ45 jack 908 .", "FIG. 35C is the wireless version.", "[0284] Multiple legacy appliances may be connected to a common interface network appliance system as shown in FIG. 36 (wired version) and FIG. 36A (wireless version).", "As there shown, the interface 920 has multiple terminals 901 , 902 , 920 , 921 and 922 for contact type devices and/or appliance jacks 924 , 925 , such as could be in communication with RS-232 signals, for connecting numerous legacy appliances such as the retina reader 926 , proximity reader 927 , swipe reader 928 and keypad display 929 .", "All of these are connected to the network via a connector such as a wire via RJ-45 jack 908 (FIG.", "36) or via a wireless connection card 914 (FIG.", "36A).", "As before, the power supply 912 may be used in either version.", "[0285] [0285 ]FIG. 37 is an enhancement wherein a network sensor in accordance with the subject invention includes an integrated interface for connecting a legacy appliance to the network via the network sensor system.", "In this enhancement the proximity reader/controller 930 has an LED sensor 931 as is well known in the art and includes an RJ-45 jack for connecting the sensor to the network.", "As previously described, a wireless version is also supported.", "The sensor includes terminals or connectors 901 , 902 and 920 for connecting various legacy appliances such as, by way of example the electric door strike 906 or the door contacts 923 .", "FIG. 37A shows the wireless version.", "FIG. 37B shows a door strike 906 with an R45 jack 924 and optional door contacts 923 .", "FIG. 37C is the wireless version.", "[0286] Other sensors/devices may be similarly enhanced, as shown with the swipe reader 932 of FIG. 38.", "[0287] [0287] 38 A is the wireless version of 38 .", "[0288] A keypad entry appliance 934 is similarly enhanced as shown in FIG. 39.", "[0289] [0289] 39 A is the wireless version of 39 .", "[0290] A further enhancement is shown in FIGS. 40 - 40 C. In this enhancement a wireless proximity sensor 934 for monitoring movement within the marked zones, see zone 936 , around monitored door 938 is connected to the network via the wireless transmitter/receiver card 526 and antenna 528 to a wireless access point interface 287 .", "As is better shown in FIG. 40A, the circuitry for supporting this sensor 934 is identical to the circuitry shown and described in FIG. ??", "The wireless version is shown in FIG. ??", "and is consistent with the circuitry shown in FIG. ??", "[0291] [0291 ]FIGS. 40C and 40D show an enhancement of the door proximity sensor shown in FIG. ??", "with a message display such as, by way of example, the EXIT display 940 .", "In this configuration a power supply comprising the AC input, a transformer 942 and a battery charger 944 provides power to the display.", "This provides power to the lamp display 940 in the normal manner, and can also be used to power the IP controller 500 .", "[0292] The wireless connection can be made via a wireless antenna 943 or by coupling to the AC power wiring 945 such as through RF coupling capacitors 947 .", "The wireless/power carrier version is shown in FIG. 40D and is consistent with the changes made in the previously discussed embodiments.", "[0293] [0293 ]FIGS. 41 and 41A show a wired universal interface network appliance and wireless universal interface network interface, respectively.", "This configuration of the interface 946 includes an independent connection to a power supply as indicated at 948 , or may be powered over the LAN 950 as has been previously discussed.", "The LAN connection such as the RJ-45 jack 950 in the configuration of FIG. 41 or the wireless connector 952 of FIG. 41A may be utilized.", "A plurality of terminal connectors 954 are provided for connecting the legacy devices such as the fire strobe display alarm 956 and the pull-handle alarm 958 .", "The legacy devices can be powered from the LAN also, utilizing the power output terminals at 954 .", "[0294] [0294 ]FIG. 42 shows a pull-handle network appliance 959 modified for direct network hook-up using a wired RJ-45 jack 960 .", "FIG. 42A is a wireless version of the pull-handle network appliance with the wireless modifications previously described.", "[0295] A wired exit device network appliance is shown in FIG. 43.", "The wireless version of the exit device network appliance is shown in FIG. 43A.", "In this enhancement the exit device includes a latch 962 , a push bar 964 and a key lock 966 .", "Action on any of these elements will transmit a signal via wire 968 to show activity at the door.", "The wire is connected to terminals on the universal interface 946 , which is in turn connected to the network 970 via a CAT-5 wire or other cabling to the universal interface.", "A wireless version is shown in FIG. 43A and includes the external power supply 289 , the wireless access component 380 , and the wireless access point 287 , as with previously described enhancements.", "[0296] A keypad mortise lock entry device network appliance is shown in FIG. 44, with the wireless version being depicted in FIG. 44A.", "The keypad lock device 972 includes a keypad 974 , backup key lock 976 and a door handle 976 , each of which will generate a signal when activated.", "The signal is carried from the control box 980 to a universal interface 946 for connection to the LAN 970 .", "A wireless version is shown in FIG. 44A.", "[0297] The keypad lock 974 is replaced by a card 986 and swipe reader 984 in FIG. 45 (wired) and FIG. 45A (wireless).", "A magnetic or optical card reader 990 and compatible card 992 is shown in FIG. 46 (wired) and FIG. 46A (wireless).", "[0298] An alternative universal connector interface network appliance 996 is shown in FIGS. 47 (wired) and 47 A (wireless).", "The universal connector interface network appliance includes a plurality of terminals for providing power out ( 998 ), input from legacy devices ( 999 ) and various output signals other than network ( 1000 ).", "Applications of the universal interface network appliance are shown in FIG. 48 wherein an electric strike 1002 and latch 1004 , an electric strike 1006 and a magnetic contact 1008 .", "FIG. 49 shows additional universal interface applications using legacy appliances.", "[0299] [0299 ]FIG. 50 is block diagram of the circuitry for supporting a multiple appliance security system in accordance with the subject invention.", "The full schematic is shown in FIGS. 51 and 51A- 51 BB.", "With reference to FIG. 50, the security appliance 5 includes a system processor 75 having both Read Only Memory (ROM) and Random Access Memory (RAM) components 1025 and 1026 , respectively.", "A contact closure interface 1028 is provided for connecting any combination of simple external appliances to the security appliance center.", "Specifically, these appliances are generally limited to ON/OFF conditions and responses The RS-232 interface 1030 is provided for connecting more sophisticated external appliances such as, by way of example, the listed appliances and the appliances described elsewhere herein.", "A DTMF/CLID detector 1032 and phone line circuit monitor 1034 provides connection to an external telephone 1036 and to the telephone network 1038 .", "External power is provided to the system either through the wired LAN interface 80 and the network power module 1040 .", "External power may also be provided by the power supply 289 or through the option AC power brick 1042 .", "The system is capable of wireless connection to the network 90 via the wireless network interface 85 and the wireless access point 87 , or alternatively by wired connection to the network via network interface 80 .", "[0300] While certain embodiments and features of the invention have been described in detail herein, it will be readily understood that the invention includes all modifications and enhancements within the scope and spirit of the following claims." ]
[0001] This nonprovisional application claims priority under 35 U.S.C. § 119(a) on German Patent Application No. DE 102004010890.0 filed in Germany on Mar. 6, 2004, which is herein incorporated by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to a method and a circuit arrangement for switching an electronic circuit into a power-saving mode by a switchover signal. [0004] 2. Description of the Background Art [0005] Switchover into a power-saving mode is necessary in particular for circuits powered by a battery voltage, for example in automotive or mobile radio applications, in order to minimize power consumption during the circuit's inactive phases. “Inactive phases” are, for example, those periods of time during which the circuit, which in particular can be an integrated circuit, e.g. an infrared receiver, transmits no data to other electronic assemblies, e.g. a microcontroller. [0006] In prior art methods and circuit arrangements of the aforementioned type, a connecting pin of a circuit is dedicated exclusively to serve as an input pin for the switchover signal, or else an additional pin is provided for the switchover signal. It can be seen as a disadvantage here that either a pin of the circuit is unavailable for other applications, or the provision of an additional pin entails additional manufacturing expense, and is to be avoided in particular in the course of advancing miniaturization of electronic structures, not least on account of the additional space required. SUMMARY OF THE INVENTION [0007] It is therefore an object of the present invention to provide a method and circuit arrangement such that the above-mentioned disadvantages are avoided. [0008] The object is attained in a method of the aforementioned type in that a data output pin of the circuit is also used as an input pin for an external signal on the basis of which the switchover signal is then produced. In order to achieve the object in a circuit arrangement of the aforementioned type, provision is made that a data output pin of the circuit can also be used as an input pin for an external signal, with the external signal being the basis for producing the switchover signal. In this way the invention allows the function of a power-saving mode without “tying up” a connecting pin of the circuit or requiring the provision of an additional pin. [0009] In a further development of the method according to an embodiment of the invention, provision is made that a potential value at the data output pin is compared with a reference value, by which a first internal control signal is generated. The first internal control signal is then logically combined with a second internal control signal, and the result of the combination is then used as the switchover signal. Here, the second internal control signal preferably represents an activity of data transmission to the data output pin, so that according to the invention switchover to the power-saving mode can only occur if the second internal control signal indicates a state of absence of data activity. In this way the data output pin effectively functions as a switchover control input only when the circuit to be controlled is not active at the time. [0010] In a circuit arrangement according to the invention, corresponding provision can be made to connect a comparator to the data output pin to compare the external signal to a reference signal and generate a first internal control signal as a function of the comparison result, with the circuit arrangement preferably having an additional signal generating means to indicate an activity of the data transmission to the data output pin by a second internal control signal. In order, as already mentioned above, to permit the use of the data output pin for the purpose of a mode switch only during inactivity of the circuit, the inventive circuit arrangement advantageously has a logical combiner for the first and second internal control signals which is further characterized in that the switchover signal can be generated by the combiner. [0011] To further reduce power consumption in the power-saving mode, in a further embodiment of the present invention, it is provided that, once switchover to the power-saving mode takes place, a pull-up resistor connected between the data output pin and a connection for a supply voltage is replaced by a low current source. Thus, a circuit arrangement can have a switch to replace a pull-up resistor that is arranged between the data output pin and a supply voltage connection with a low current source. In the operating mode of the circuit, the pull-up resistor provides for a defined potential at the data output pin, but would otherwise result in too much current as a result of the applied supply voltage. According to an embodiment of the invention, the switch, which is provided by circuitry to replace the resistor, can also be controlled by the switchover signal. [0012] According to an alternate embodiment of the circuit arrangement, the low current source and the pull-up resistor are connected in parallel and the switch are transistors that are connected directly ahead of the low current source and/or directly ahead of the pull-up resistor. The transistors, like the circuit, can be controlled by the switchover signal. [0013] For the purpose of the simplest possible design of the circuit arrangement according to the invention, the low current source can be embodied as a resistor with a high value in comparison to the pull-up resistor. [0014] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. BRIEF DESCRIPTION OF THE DRAWINGS [0015] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein the single FIGURE shows a circuit arrangement according to an embodiment of the present invention. DETAILED DESCRIPTION [0016] The single FIGURE shows a circuit arrangement according to an embodiment of the present invention for switchover of an integrated circuit (IC) 1 at the direction of an external microcontroller (μC) 2 . In the example embodiment shown, the integrated circuit 1 is a circuit designed to receive signals in an infrared (IR) portion of the spectrum, i.e. an IR receiver. During normal operation the integrated circuit 1 draws a current I S from a supply voltage V S , for example a battery voltage, and in a power-saving mode (shutdown mode, SD) draws a current I SD that is reduced in comparison to the current I S . [0017] A circuit arrangement 3 in accordance with the invention is wired in operative connection to the integrated circuit 1 . In this regard, the circuit arrangement 3 and the integrated circuit 1 can also be integrated together (monolithic), as indicated in the FIGURE by a dashed line 4 (integrated unit). [0018] In accordance with the example embodiment shown, the circuit arrangement 3 includes a data output pin 1 . 1 of the IC 1 , through which the latter transmits received data DAT to the microcontroller 2 . Within the circuit arrangement 3 , the data output pin 1 . 1 is connected to a node 3 . 1 that lies between a supply voltage V S , for example, a battery voltage in which V S =5V, and a ground potential GND. A first switch, which can be a NMOS transistor 3 . 2 , hereinafter referred to as the output transistor, is connected between the node 3 . 1 and the ground potential GND. The output transistor 3 . 2 can have a self-cutoff characteristic, and can function as a pull-down transistor with regard to the node 3 . 1 . [0019] The gate electrode of the output transistor 3 . 2 is connected to a functional unit 3 . 3 of the circuit arrangement 3 , which can be a demodulator, for example, by which the output transistor 3 . 2 can be controlled at its gate electrode by a signal D. The signal D can be a binary data signal from the IC 1 that is isolated in the functional unit 3 . 3 from a carrier wave, e.g., a series of HIGH and LOW level values. Whereby, the output transistor 3 . 2 is cut off in the case when D=0 and conducts when D=1. In the latter case, the node 3 . 1 is at the ground potential GND. [0020] Connected between the node 3 . 1 and a connection for the supply voltage V S , starting from the node 3 . 1 there are a pull-up resistor R 1 and, in series therewith, a second switch, which can be a self-conducting PMOS transistor 3 . 4 . In parallel therewith, the circuit arrangement 3 has a third switch, which can be an additional self-conducting PMOS transistor 3 . 5 , and a current source 3 . 6 that supplies a low “sense” current I L on, for example, the order of I L =100 nA. Alternatively, the current source 3 . 6 can also be designed as a resistor R 2 with a value that is high relative to the pull-up resistor R 1 (e.g., R 1 =100 kΩ, R 2 □R 1 ), as is shown in the FIGURE with the aid of the dotted connections. Also starting from the supply voltage V S , there are arranged first the transistor 3 . 5 and then the current source 3 . 6 /the resistor R 2 , where the connections of the pull-up resistor R 1 and the current source 3 . 6 /the resistor R 2 , which face the node 3 . 1 , terminate in a common node 3 . 7 . [0021] Additionally, the circuit arrangement 3 has a comparison means in the form of a comparator 3 . 8 whose inputs for comparison are connected to the node 3 . 7 and to a reference voltage V R , with V R >GND. An output signal S 1 of the comparator 3 . 8 , which functions as a first internal control signal, is connected to one of the inputs of a logical combiner, which can be an AND gate 3 . 9 . The second input of the AND gate 3 . 9 is connected to the functional unit 3 . 3 for receiving a second internal control signal S 2 , by which the functional unit 3 . 3 indicates an activity of data transmission (hereinafter referred to as data activity) from IC 1 to data output pin 1 . 1 . In the embodiment of the invention shown, for example, S 2 =1 in the absence of data activity (no data burst to the output pin 1 . 1 ). [0022] The output of the AND gate 3 . 9 is connected to an additional node 3 . 10 , which branches off to a gate electrode of the PMOS transistor 3 . 4 , to a gate electrode of the PMOS 3 . 5 via an inverter 3 . 11 , and to the IC 1 (signal SD′). In this way, both of the PMOS transistors 3 . 4 , 3 . 5 (complementary to one another) and also the IC 1 can be controlled by the output of the AND gate 3 . 9 . [0023] In normal operation, the transistor 3 . 4 conducts. As already mentioned, the output transistor 3 . 2 is controlled by the functional unit 3 . 3 . Thus, via the pull-up resistor R 1 an output signal DAT can be accessed at output pin 1 . 1 as a direct reproduction of the signal D for further processing by the microcontroller 2 . The current Is typically flows at approximately 500 μA. [0024] The circuit arrangement 3 now operates to switch IC 1 into the power-saving mode as follows: the data output pin 1 . 1 is externally brought to ground potential GND by the microcontroller 2 . This process is symbolized in the FIGURE by the arrow SD from the microcontroller 2 to the output pin 1 . 1 . As a result the nodes 3 . 1 , 3 . 7 drop the voltage at one input of the comparator 3 . 8 below the reference value V R so that the comparator 3 . 8 generates the signal S 1 , here S 1 =1. This signal is combined with the signal S 2 by the AND gate 3 . 9 , with the AND gate then providing a HIGH level output signal to node 3 . 10 when S 1 =1 and S 2 =1 at the same time, which is to say when no data activity is taking place and the external SD signal has been given. [0025] The output signal of the AND gate 3 . 9 serves firstly as an (internal) shutdown signal SD′ for IC 1 . Consequently, the IC 1 can only be switched over into the power-saving mode on the basis of the external signal SD when no data is being transmitted at this moment. [0026] Thus, the data output pin 1 . 1 of the integrated circuit 1 is used simultaneously as an input pin for the external shutdown signal SD, according to which—as already described in detail above—the internal switchover signal SD′ is subsequently generated. [0027] Secondly, an additional power reduction is achieved on account of the controlling connections from the node 3 . 10 to the transistors 3 . 4 , 3 . 5 in the power-saving mode according to the invention. In the event of a HIGH level signal at node 3 . 10 , the PMOS transistor 3 . 4 cuts off, while the PMOS transistor 3 . 5 conducts on account of the inverter 3 . 11 . In this way, the pull-up resistor R 1 is replaced by the current source 3 . 6 or the resistor R 2 . This makes it possible to avoid having an excessively high current I=V S /R 1 =50 μA flow from the supply voltage V S through the pull-up resistor R 1 in the power-saving mode of the IC 1 . In contrast, the quiescent current consumption of IC 1 is only approximately I SD =100 nA. According to the invention, on account of I L =100 nA, a total quiescent current in power-saving mode of I SD +I L =200 nA results, which is to say one 250 th of the quiescent current through the resistor R 1 . Alternatively, the same result is achieved using a resistor with a high value R 2 =50 MΩ in comparison to the pull-up resistor R 1 . [0028] It is necessary to switch on the current I L or VS/R 2 in order to set the output pin 1 . 1 at a defined potential even in power-saving mode, i.e. in the absence of data activity; without this current, the output pin would float. [0029] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.
A method and circuit arrangement are provided for switching an electronic circuit into a power-saving mode by a switchover signal that is characterized in that a data output pin of the circuit is simultaneously used as an input pin for an external signal on the basis of which the switchover signal is then produced. When method or circuit arrangement is used, an electronic circuit can be placed in the power-saving mode without the need to provide an additional connecting pin for this purpose.
Summarize the patent information, clearly outlining the technical challenges and proposed solutions.
[ "[0001] This nonprovisional application claims priority under 35 U.S.C. § 119(a) on German Patent Application No. DE 102004010890.0 filed in Germany on Mar. 6, 2004, which is herein incorporated by reference.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] The present invention relates to a method and a circuit arrangement for switching an electronic circuit into a power-saving mode by a switchover signal.", "[0004] 2.", "Description of the Background Art [0005] Switchover into a power-saving mode is necessary in particular for circuits powered by a battery voltage, for example in automotive or mobile radio applications, in order to minimize power consumption during the circuit's inactive phases.", "“Inactive phases”", "are, for example, those periods of time during which the circuit, which in particular can be an integrated circuit, e.g. an infrared receiver, transmits no data to other electronic assemblies, e.g. a microcontroller.", "[0006] In prior art methods and circuit arrangements of the aforementioned type, a connecting pin of a circuit is dedicated exclusively to serve as an input pin for the switchover signal, or else an additional pin is provided for the switchover signal.", "It can be seen as a disadvantage here that either a pin of the circuit is unavailable for other applications, or the provision of an additional pin entails additional manufacturing expense, and is to be avoided in particular in the course of advancing miniaturization of electronic structures, not least on account of the additional space required.", "SUMMARY OF THE INVENTION [0007] It is therefore an object of the present invention to provide a method and circuit arrangement such that the above-mentioned disadvantages are avoided.", "[0008] The object is attained in a method of the aforementioned type in that a data output pin of the circuit is also used as an input pin for an external signal on the basis of which the switchover signal is then produced.", "In order to achieve the object in a circuit arrangement of the aforementioned type, provision is made that a data output pin of the circuit can also be used as an input pin for an external signal, with the external signal being the basis for producing the switchover signal.", "In this way the invention allows the function of a power-saving mode without “tying up”", "a connecting pin of the circuit or requiring the provision of an additional pin.", "[0009] In a further development of the method according to an embodiment of the invention, provision is made that a potential value at the data output pin is compared with a reference value, by which a first internal control signal is generated.", "The first internal control signal is then logically combined with a second internal control signal, and the result of the combination is then used as the switchover signal.", "Here, the second internal control signal preferably represents an activity of data transmission to the data output pin, so that according to the invention switchover to the power-saving mode can only occur if the second internal control signal indicates a state of absence of data activity.", "In this way the data output pin effectively functions as a switchover control input only when the circuit to be controlled is not active at the time.", "[0010] In a circuit arrangement according to the invention, corresponding provision can be made to connect a comparator to the data output pin to compare the external signal to a reference signal and generate a first internal control signal as a function of the comparison result, with the circuit arrangement preferably having an additional signal generating means to indicate an activity of the data transmission to the data output pin by a second internal control signal.", "In order, as already mentioned above, to permit the use of the data output pin for the purpose of a mode switch only during inactivity of the circuit, the inventive circuit arrangement advantageously has a logical combiner for the first and second internal control signals which is further characterized in that the switchover signal can be generated by the combiner.", "[0011] To further reduce power consumption in the power-saving mode, in a further embodiment of the present invention, it is provided that, once switchover to the power-saving mode takes place, a pull-up resistor connected between the data output pin and a connection for a supply voltage is replaced by a low current source.", "Thus, a circuit arrangement can have a switch to replace a pull-up resistor that is arranged between the data output pin and a supply voltage connection with a low current source.", "In the operating mode of the circuit, the pull-up resistor provides for a defined potential at the data output pin, but would otherwise result in too much current as a result of the applied supply voltage.", "According to an embodiment of the invention, the switch, which is provided by circuitry to replace the resistor, can also be controlled by the switchover signal.", "[0012] According to an alternate embodiment of the circuit arrangement, the low current source and the pull-up resistor are connected in parallel and the switch are transistors that are connected directly ahead of the low current source and/or directly ahead of the pull-up resistor.", "The transistors, like the circuit, can be controlled by the switchover signal.", "[0013] For the purpose of the simplest possible design of the circuit arrangement according to the invention, the low current source can be embodied as a resistor with a high value in comparison to the pull-up resistor.", "[0014] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter.", "However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.", "BRIEF DESCRIPTION OF THE DRAWINGS [0015] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein the single FIGURE shows a circuit arrangement according to an embodiment of the present invention.", "DETAILED DESCRIPTION [0016] The single FIGURE shows a circuit arrangement according to an embodiment of the present invention for switchover of an integrated circuit (IC) 1 at the direction of an external microcontroller (μC) 2 .", "In the example embodiment shown, the integrated circuit 1 is a circuit designed to receive signals in an infrared (IR) portion of the spectrum, i.e. an IR receiver.", "During normal operation the integrated circuit 1 draws a current I S from a supply voltage V S , for example a battery voltage, and in a power-saving mode (shutdown mode, SD) draws a current I SD that is reduced in comparison to the current I S .", "[0017] A circuit arrangement 3 in accordance with the invention is wired in operative connection to the integrated circuit 1 .", "In this regard, the circuit arrangement 3 and the integrated circuit 1 can also be integrated together (monolithic), as indicated in the FIGURE by a dashed line 4 (integrated unit).", "[0018] In accordance with the example embodiment shown, the circuit arrangement 3 includes a data output pin 1 .", "1 of the IC 1 , through which the latter transmits received data DAT to the microcontroller 2 .", "Within the circuit arrangement 3 , the data output pin 1 .", "1 is connected to a node 3 .", "1 that lies between a supply voltage V S , for example, a battery voltage in which V S =5V, and a ground potential GND.", "A first switch, which can be a NMOS transistor 3 .", "2 , hereinafter referred to as the output transistor, is connected between the node 3 .", "1 and the ground potential GND.", "The output transistor 3 .", "2 can have a self-cutoff characteristic, and can function as a pull-down transistor with regard to the node 3 .", "1 .", "[0019] The gate electrode of the output transistor 3 .", "2 is connected to a functional unit 3 .", "3 of the circuit arrangement 3 , which can be a demodulator, for example, by which the output transistor 3 .", "2 can be controlled at its gate electrode by a signal D. The signal D can be a binary data signal from the IC 1 that is isolated in the functional unit 3 .", "3 from a carrier wave, e.g., a series of HIGH and LOW level values.", "Whereby, the output transistor 3 .", "2 is cut off in the case when D=0 and conducts when D=1.", "In the latter case, the node 3 .", "1 is at the ground potential GND.", "[0020] Connected between the node 3 .", "1 and a connection for the supply voltage V S , starting from the node 3 .", "1 there are a pull-up resistor R 1 and, in series therewith, a second switch, which can be a self-conducting PMOS transistor 3 .", "4 .", "In parallel therewith, the circuit arrangement 3 has a third switch, which can be an additional self-conducting PMOS transistor 3 .", "5 , and a current source 3 .", "6 that supplies a low “sense”", "current I L on, for example, the order of I L =100 nA.", "Alternatively, the current source 3 .", "6 can also be designed as a resistor R 2 with a value that is high relative to the pull-up resistor R 1 (e.g., R 1 =100 kΩ, R 2 □R 1 ), as is shown in the FIGURE with the aid of the dotted connections.", "Also starting from the supply voltage V S , there are arranged first the transistor 3 .", "5 and then the current source 3 .", "6 /the resistor R 2 , where the connections of the pull-up resistor R 1 and the current source 3 .", "6 /the resistor R 2 , which face the node 3 .", "1 , terminate in a common node 3 .", "7 .", "[0021] Additionally, the circuit arrangement 3 has a comparison means in the form of a comparator 3 .", "8 whose inputs for comparison are connected to the node 3 .", "7 and to a reference voltage V R , with V R >GND.", "An output signal S 1 of the comparator 3 .", "8 , which functions as a first internal control signal, is connected to one of the inputs of a logical combiner, which can be an AND gate 3 .", "9 .", "The second input of the AND gate 3 .", "9 is connected to the functional unit 3 .", "3 for receiving a second internal control signal S 2 , by which the functional unit 3 .", "3 indicates an activity of data transmission (hereinafter referred to as data activity) from IC 1 to data output pin 1 .", "1 .", "In the embodiment of the invention shown, for example, S 2 =1 in the absence of data activity (no data burst to the output pin 1 .", "1 ).", "[0022] The output of the AND gate 3 .", "9 is connected to an additional node 3 .", "10 , which branches off to a gate electrode of the PMOS transistor 3 .", "4 , to a gate electrode of the PMOS 3 .", "5 via an inverter 3 .", "11 , and to the IC 1 (signal SD′).", "In this way, both of the PMOS transistors 3 .", "4 , 3 .", "5 (complementary to one another) and also the IC 1 can be controlled by the output of the AND gate 3 .", "9 .", "[0023] In normal operation, the transistor 3 .", "4 conducts.", "As already mentioned, the output transistor 3 .", "2 is controlled by the functional unit 3 .", "3 .", "Thus, via the pull-up resistor R 1 an output signal DAT can be accessed at output pin 1 .", "1 as a direct reproduction of the signal D for further processing by the microcontroller 2 .", "The current Is typically flows at approximately 500 μA.", "[0024] The circuit arrangement 3 now operates to switch IC 1 into the power-saving mode as follows: the data output pin 1 .", "1 is externally brought to ground potential GND by the microcontroller 2 .", "This process is symbolized in the FIGURE by the arrow SD from the microcontroller 2 to the output pin 1 .", "1 .", "As a result the nodes 3 .", "1 , 3 .", "7 drop the voltage at one input of the comparator 3 .", "8 below the reference value V R so that the comparator 3 .", "8 generates the signal S 1 , here S 1 =1.", "This signal is combined with the signal S 2 by the AND gate 3 .", "9 , with the AND gate then providing a HIGH level output signal to node 3 .", "10 when S 1 =1 and S 2 =1 at the same time, which is to say when no data activity is taking place and the external SD signal has been given.", "[0025] The output signal of the AND gate 3 .", "9 serves firstly as an (internal) shutdown signal SD′ for IC 1 .", "Consequently, the IC 1 can only be switched over into the power-saving mode on the basis of the external signal SD when no data is being transmitted at this moment.", "[0026] Thus, the data output pin 1 .", "1 of the integrated circuit 1 is used simultaneously as an input pin for the external shutdown signal SD, according to which—as already described in detail above—the internal switchover signal SD′ is subsequently generated.", "[0027] Secondly, an additional power reduction is achieved on account of the controlling connections from the node 3 .", "10 to the transistors 3 .", "4 , 3 .", "5 in the power-saving mode according to the invention.", "In the event of a HIGH level signal at node 3 .", "10 , the PMOS transistor 3 .", "4 cuts off, while the PMOS transistor 3 .", "5 conducts on account of the inverter 3 .", "11 .", "In this way, the pull-up resistor R 1 is replaced by the current source 3 .", "6 or the resistor R 2 .", "This makes it possible to avoid having an excessively high current I=V S /R 1 =50 μA flow from the supply voltage V S through the pull-up resistor R 1 in the power-saving mode of the IC 1 .", "In contrast, the quiescent current consumption of IC 1 is only approximately I SD =100 nA.", "According to the invention, on account of I L =100 nA, a total quiescent current in power-saving mode of I SD +I L =200 nA results, which is to say one 250 th of the quiescent current through the resistor R 1 .", "Alternatively, the same result is achieved using a resistor with a high value R 2 =50 MΩ in comparison to the pull-up resistor R 1 .", "[0028] It is necessary to switch on the current I L or VS/R 2 in order to set the output pin 1 .", "1 at a defined potential even in power-saving mode, i.e. in the absence of data activity;", "without this current, the output pin would float.", "[0029] The invention being thus described, it will be obvious that the same may be varied in many ways.", "Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims." ]
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser. No. 13/671,051, filed Nov. 7, 2012. FIELD OF THE INVENTION [0002] The present invention relates to the field of Internet security. More particularly, the invention relates to a method and system suitable to respond to malicious attacks against a computer system, of the denial-of-service type. BACKGROUND OF THE INVENTION [0003] Distributed denial-of-service attack (DDoS attack) is an attempt to make a machine or network resource unavailable to its intended users. It generally consists of the efforts of one or more people to temporarily or indefinitely interrupt or suspend services of a host connected to the Internet. [0004] One common method of denial-of-service (DoS) attack involves saturating the target machine with external communications requests, such that it cannot respond to legitimate traffic, or responds so slowly as to be rendered essentially unavailable. Such attacks usually lead to a server overload. In general terms, DoS attacks are implemented by either forcing the targeted computer(s) to reset, or consuming its resources so that it can no longer provide its intended service or obstructing the communication media between the intended users and the victim so that they can no longer communicate adequately. [0005] A “denial-of-service” attack is characterized by an explicit attempt by attackers to prevent legitimate users of a service from using that service. There are two general forms of DoS attacks: those that crash services and those that flood services. [0006] A DoS attack can be perpetrated in a number of ways. The five basic types of attack are: Consumption of computational resources, such as bandwidth, disk space, or processor time; Disruption of configuration information, such as routing information; Disruption of state information, such as unsolicited resetting of TCP sessions; Disruption of physical network components; Obstructing the communication media between the intended users and the victim so that they can no longer communicate adequately. [0012] Perpetrators of DDoS attacks typically target sites or services hosted on high-profile web servers such as banks, credit card payment gateways, etc. [0013] A distributed denial of service attack (DDoS) occurs when multiple systems flood the bandwidth or resources of a targeted system, usually one or more web servers. These systems are compromised by attackers using a variety of methods. [0014] Malware can carry DDoS attack mechanisms, such as MyDoom, the DoS mechanism of which was triggered on a specific date and time. This type of DDoS involves hardcoding the target IP address prior to release of the malware and no further interaction is then necessary to launch the attack. [0015] DDoS tools, such as the well-known Stacheldraht, use classic DoS attack methods centered on IP spoofing and amplification like smurf attacks and fraggle attacks (also known as bandwidth consumption attacks). Newer tools can use DNS servers for DoS purposes. [0016] The term “DDoS” refers to DoS attacks launched using many systems simultaneously to launch attacks against a remote host. [0017] DDoS attacks have become more frequent against financial institutions, such as banks and have been known to disrupt their activity and that of their customers. Such attacks are often directed against the DNS server of the institution, thereby preventing the resolution of the hostname to which a customer's web browser is directed. It is therefore clear that it would be desirable to provide means by which regular activities of such institutions, as well as of any other body facing the same malicious attacks, could be maintained in spite of all the attacks. [0018] It is an object of the present invention to provide a system and a method which enable a system that finds itself under a DDoS attack directed against its DNS server to continue functioning in spite of the attack. [0019] It is another object of the invention to provide software means associated with the client software available to a customer, which are suitable to prevent or limit the difficulty of the customer in reaching the desired host. [0020] Other objects and advantages of the invention will become apparent as the description proceeds. SUMMARY OF THE INVENTION [0021] The invention relates to a method for defending a computer system comprising a DNS server against a DoS or a DDoS attack directed at said DNS server, comprising replacing the address of said system provided by a user to a client software with an alternative address, wherein said address is replaced by a software agent associated with said user, such that said client software is capable of connecting with said system. [0022] According to one embodiment of the invention the software agent is integral with the client software or web browser used by the user. According to another embodiment of the invention the software agent is separate software that interacts with a browser or other client software. [0023] The alternative address can be the address of an alternative DNS server or a static IP address of a resource that must be reached by the user's client software. [0024] The invention is further directed to software agent suitable to detect a failure to resolve a hostname/domain of a target system and, when such failure is detected, to redirect client software used to communicate with said target system to a different address. [0025] Also encompassed by the invention is a system for defending against DoS and DDoS attacks, comprising one or more of an alternative DNS server, a static IP address and a configuration server, the address of which have not being advertised. BRIEF DESCRIPTION OF THE DRAWINGS [0026] FIG. 1 is a schematic flow chart of an illustrative system operating in accordance with one embodiment of the invention, which employs a Configuration Server. DETAILED DESCRIPTION OF THE INVENTION [0027] According to the invention, when a DNS server of a system becomes unavailable due to a DDoS attack and, accordingly, the browser of a user who is attempting to connect to that system is not able to obtain DNS resolution of the hostname/domain of that system, the user's browser is directed to a different address than selected by the user. Said different address can be created in a variety of manners and it replaces the hostname or other address originally submitted to the browser by the user (either by using a bookmark or by typing it) in a manner that is transparent to the user himself. In the examples to follow the various operations described can be performed by software integral with the client software or web browser used by the user, or by a separate software that interacts with such browser or client software. For the purpose of illustration two alternative embodiment of the invention are discussed below. Using an Alternative DNS Server [0028] According to this embodiment of the invention an alternative DNS server is provided, for use in this scenario, which is not advertised and not made known to the public. In this embodiment once a DoS or a DDoS attack is detected the software provided to the user instructs the client software used to communicate with the system to move to address resolution using the alternative DNS server. [0029] In this way, users are able to continue to receive service while the system deals with the attack. As will be apparent to the skilled person, because the DNS server is not advertised only users provided with client software distributed by the relevant system will be able to reach it. [0030] A schematic flow chart of an illustrative system operating in accordance with one embodiment of the invention, which employs a Configuration Server, is shown in FIG. 1 . The operation of this illustrative system is self-evident from the flow chart and this description and, therefore, is not further discussed for the sake of brevity. Using a Static IP Address [0031] In an alternative embodiment of the invention no alternative DNS server is provided. Instead, the resource that must be reached by the user is associated with a static IP address, which again is not advertised and is only available to the software that is integral, or works together with the client software used by the user to access the system. Once the regular DNS server of the system becomes unavailable the software provided in or with the client software replaces the request to the DNS server with the static IP address, thus making it possible for the user to obtain service. [0032] Several ways are available to the software to perform the replacement of the DNS server address with either that of an alternative DNS server or a static IP, or any other desired location. The actual method used depends on the operating system of the user and the skilled person will implement the method that is the most suitable for a given operating system. For instance, it is possible on the operating system level to utilize the DNS API process. In other operating systems is possible to interfere with the operation of the DNS client or, on the network level, it may be desirable to intercept the UDP outgoing packet and then to create a fake incoming packet suitable to redirect the client software as desired. [0033] The invention may operate in different modes, three of which are detailed below for the purpose of illustration: [0034] 1. Automatic mode: the software agent located on the user's terminal detects a certain number of consecutive failures for DNS resolution of a particular hostname/domain and/or failure ratio greater than a given threshold. The software agent then activates the alternative DNS/static address resolution for the relevant hostname/domain. [0035] 2. Manual mode: the software agent periodically polls a “configuration server”, which is responsible for monitoring the DNS server and for identifying DDoS activity. Monitoring the bank's DNS server is one way of getting notified about a DNS DDoS attack against the bank's DNS server, but other methods (such as, for instance, receiving an alert directly from the owner of the DNS server) can of course be employed. When the configuration server provides a configuration with a DDoS flag turned on, the software agent transitions to the alternative DNS/static IP address. [0036] 3. Manual mode with fallback: this mode operates as mode (2) with the exception that if the configuration server itself is not responsive the software agent transitions to the alternative DNS/static IP address on the assumption that the configuration server itself has come under DDoS attack. [0037] All the above description and examples have been provided for the purpose of illustration and are not meant to limit the invention in any way except as provided by the appended claims.
Managing denial-of-service attacks by intercepting a query by a client software executed by a computer to resolve at a DNS server a network address associated with a target computer system, determining if the DNS server is under denial-of-service attack, and providing to the client software, in response to the query, an alternate network address associated with the target computer system if the DNS server is under denial-of-service attack.
Briefly summarize the main idea's components and working principles as described in the context.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser.", "No. 13/671,051, filed Nov. 7, 2012.", "FIELD OF THE INVENTION [0002] The present invention relates to the field of Internet security.", "More particularly, the invention relates to a method and system suitable to respond to malicious attacks against a computer system, of the denial-of-service type.", "BACKGROUND OF THE INVENTION [0003] Distributed denial-of-service attack (DDoS attack) is an attempt to make a machine or network resource unavailable to its intended users.", "It generally consists of the efforts of one or more people to temporarily or indefinitely interrupt or suspend services of a host connected to the Internet.", "[0004] One common method of denial-of-service (DoS) attack involves saturating the target machine with external communications requests, such that it cannot respond to legitimate traffic, or responds so slowly as to be rendered essentially unavailable.", "Such attacks usually lead to a server overload.", "In general terms, DoS attacks are implemented by either forcing the targeted computer(s) to reset, or consuming its resources so that it can no longer provide its intended service or obstructing the communication media between the intended users and the victim so that they can no longer communicate adequately.", "[0005] A “denial-of-service”", "attack is characterized by an explicit attempt by attackers to prevent legitimate users of a service from using that service.", "There are two general forms of DoS attacks: those that crash services and those that flood services.", "[0006] A DoS attack can be perpetrated in a number of ways.", "The five basic types of attack are: Consumption of computational resources, such as bandwidth, disk space, or processor time;", "Disruption of configuration information, such as routing information;", "Disruption of state information, such as unsolicited resetting of TCP sessions;", "Disruption of physical network components;", "Obstructing the communication media between the intended users and the victim so that they can no longer communicate adequately.", "[0012] Perpetrators of DDoS attacks typically target sites or services hosted on high-profile web servers such as banks, credit card payment gateways, etc.", "[0013] A distributed denial of service attack (DDoS) occurs when multiple systems flood the bandwidth or resources of a targeted system, usually one or more web servers.", "These systems are compromised by attackers using a variety of methods.", "[0014] Malware can carry DDoS attack mechanisms, such as MyDoom, the DoS mechanism of which was triggered on a specific date and time.", "This type of DDoS involves hardcoding the target IP address prior to release of the malware and no further interaction is then necessary to launch the attack.", "[0015] DDoS tools, such as the well-known Stacheldraht, use classic DoS attack methods centered on IP spoofing and amplification like smurf attacks and fraggle attacks (also known as bandwidth consumption attacks).", "Newer tools can use DNS servers for DoS purposes.", "[0016] The term “DDoS”", "refers to DoS attacks launched using many systems simultaneously to launch attacks against a remote host.", "[0017] DDoS attacks have become more frequent against financial institutions, such as banks and have been known to disrupt their activity and that of their customers.", "Such attacks are often directed against the DNS server of the institution, thereby preventing the resolution of the hostname to which a customer's web browser is directed.", "It is therefore clear that it would be desirable to provide means by which regular activities of such institutions, as well as of any other body facing the same malicious attacks, could be maintained in spite of all the attacks.", "[0018] It is an object of the present invention to provide a system and a method which enable a system that finds itself under a DDoS attack directed against its DNS server to continue functioning in spite of the attack.", "[0019] It is another object of the invention to provide software means associated with the client software available to a customer, which are suitable to prevent or limit the difficulty of the customer in reaching the desired host.", "[0020] Other objects and advantages of the invention will become apparent as the description proceeds.", "SUMMARY OF THE INVENTION [0021] The invention relates to a method for defending a computer system comprising a DNS server against a DoS or a DDoS attack directed at said DNS server, comprising replacing the address of said system provided by a user to a client software with an alternative address, wherein said address is replaced by a software agent associated with said user, such that said client software is capable of connecting with said system.", "[0022] According to one embodiment of the invention the software agent is integral with the client software or web browser used by the user.", "According to another embodiment of the invention the software agent is separate software that interacts with a browser or other client software.", "[0023] The alternative address can be the address of an alternative DNS server or a static IP address of a resource that must be reached by the user's client software.", "[0024] The invention is further directed to software agent suitable to detect a failure to resolve a hostname/domain of a target system and, when such failure is detected, to redirect client software used to communicate with said target system to a different address.", "[0025] Also encompassed by the invention is a system for defending against DoS and DDoS attacks, comprising one or more of an alternative DNS server, a static IP address and a configuration server, the address of which have not being advertised.", "BRIEF DESCRIPTION OF THE DRAWINGS [0026] FIG. 1 is a schematic flow chart of an illustrative system operating in accordance with one embodiment of the invention, which employs a Configuration Server.", "DETAILED DESCRIPTION OF THE INVENTION [0027] According to the invention, when a DNS server of a system becomes unavailable due to a DDoS attack and, accordingly, the browser of a user who is attempting to connect to that system is not able to obtain DNS resolution of the hostname/domain of that system, the user's browser is directed to a different address than selected by the user.", "Said different address can be created in a variety of manners and it replaces the hostname or other address originally submitted to the browser by the user (either by using a bookmark or by typing it) in a manner that is transparent to the user himself.", "In the examples to follow the various operations described can be performed by software integral with the client software or web browser used by the user, or by a separate software that interacts with such browser or client software.", "For the purpose of illustration two alternative embodiment of the invention are discussed below.", "Using an Alternative DNS Server [0028] According to this embodiment of the invention an alternative DNS server is provided, for use in this scenario, which is not advertised and not made known to the public.", "In this embodiment once a DoS or a DDoS attack is detected the software provided to the user instructs the client software used to communicate with the system to move to address resolution using the alternative DNS server.", "[0029] In this way, users are able to continue to receive service while the system deals with the attack.", "As will be apparent to the skilled person, because the DNS server is not advertised only users provided with client software distributed by the relevant system will be able to reach it.", "[0030] A schematic flow chart of an illustrative system operating in accordance with one embodiment of the invention, which employs a Configuration Server, is shown in FIG. 1 .", "The operation of this illustrative system is self-evident from the flow chart and this description and, therefore, is not further discussed for the sake of brevity.", "Using a Static IP Address [0031] In an alternative embodiment of the invention no alternative DNS server is provided.", "Instead, the resource that must be reached by the user is associated with a static IP address, which again is not advertised and is only available to the software that is integral, or works together with the client software used by the user to access the system.", "Once the regular DNS server of the system becomes unavailable the software provided in or with the client software replaces the request to the DNS server with the static IP address, thus making it possible for the user to obtain service.", "[0032] Several ways are available to the software to perform the replacement of the DNS server address with either that of an alternative DNS server or a static IP, or any other desired location.", "The actual method used depends on the operating system of the user and the skilled person will implement the method that is the most suitable for a given operating system.", "For instance, it is possible on the operating system level to utilize the DNS API process.", "In other operating systems is possible to interfere with the operation of the DNS client or, on the network level, it may be desirable to intercept the UDP outgoing packet and then to create a fake incoming packet suitable to redirect the client software as desired.", "[0033] The invention may operate in different modes, three of which are detailed below for the purpose of illustration: [0034] 1.", "Automatic mode: the software agent located on the user's terminal detects a certain number of consecutive failures for DNS resolution of a particular hostname/domain and/or failure ratio greater than a given threshold.", "The software agent then activates the alternative DNS/static address resolution for the relevant hostname/domain.", "[0035] 2.", "Manual mode: the software agent periodically polls a “configuration server”, which is responsible for monitoring the DNS server and for identifying DDoS activity.", "Monitoring the bank's DNS server is one way of getting notified about a DNS DDoS attack against the bank's DNS server, but other methods (such as, for instance, receiving an alert directly from the owner of the DNS server) can of course be employed.", "When the configuration server provides a configuration with a DDoS flag turned on, the software agent transitions to the alternative DNS/static IP address.", "[0036] 3.", "Manual mode with fallback: this mode operates as mode (2) with the exception that if the configuration server itself is not responsive the software agent transitions to the alternative DNS/static IP address on the assumption that the configuration server itself has come under DDoS attack.", "[0037] All the above description and examples have been provided for the purpose of illustration and are not meant to limit the invention in any way except as provided by the appended claims." ]
The invention described herein may be manufactured, used and licensed by or for the Government for Governmental purposes without the payment to me of any royalties thereon. BACKGROUND OF THE INVENTION The present invention relates to a military tank/turret weapon system. At the present time a typical military tank combat crew consists of a tank commander, a driver, a gunner and an ammunition loader. The tank commander is the officer in command of the fighting vehicle and responsible for coordinating the functions and activities of the other crew members to successfully complete the vehicle's assigned mission. The driver is responsible for the operation of the vehicle's engine systems and generally driving or otherwise maneuvering the vehicle. The gunner is responsible for operation of the vehicle's weapon systems, tracking and targeting of enemy vehicles and firing the on board weapon system thereby destroying enemy vehicles. The ammunition loader is responsible for physically selecting the particular type of ammunition ordered by the tank commander to be fired and manually loading the chosen ammunition into the weapon. Upon firing of the round, the round's cartridge case (stub case) is ejected by the weapon's breech mechanism with a force sufficient to propel the stub case toward the rear of the tank turret where it is generally received within a holding container. However, many times the stub case does not land within the holding container and the loader must manually capture the case and deposit it within the holding container. Further as the holding container fills with ejected casings, the loader must dispose of the spent casings by manually tossing the ejected stub cases outside the tank turret. Future military tank cannon vehicle systems are being designed with a combat crew of three, the commander, driver, and gunner. The ammunition loader being replaced by an automated and mechanical loading device having a high rate of fire otherwise not achievable by a human loader. The stub case ejected from the weapon's breech must now be disposed of mechanically. SUMMARY OF THE PRESENT INVENTION The present invention teaches method and apparatus whereby the ammunition stub case, ejected from the breech of a tank turret cannon, may be safely and securely captured and subsequently ejected from the tank turret. A stub case catcher mechanism is herein taught that receives and traps therein the ejected stub case ejected from the breech of a typical cannon type weapon system. The stub case catcher decelerates the stub case, absorbing it's kinetic energy thereby stopping the stub case and securing it within the catcher. Once secured within the catcher, the catcher is raised to an inclined position from which the stub case may be physically ejected from the tank turret. As the catcher is raised to the ejection position energy is stored within a torsion bar later to be released thereby providing the necessary force and energy for ejecting the stub case from the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a right side elevational view of my stub case catcher as typically mounted upon the breech of a military cannon. FIG. 2 is a left side elevational view of my stub case catcher. FIG. 3 is a top plan view showing my stub case catcher as attached to a typical weapon system. FIG. 4A illustrates my stub case catcher as mounted upon a typical cannon in the weapon firing position and ready to receive the stub case when ejected from the cannon breech. FIG. 4B illustrates the stub case catcher in its raised position subsequent to capturing therein a stub case ejected from the cannon breech. FIG. 4C illustrates the captured stub case being ejected from the stub case catcher and a new round of ammunition being simultaneously loaded into the cannon breech. FIG. 5 elevational view of my stub case catcher showing the general cation of various mechanical subassemblies. FIG. 6 is a sectional view taken along line 6--6 of FIG. 8. FIG. 7A is a cross sectional view taken along line 7--7 of FIG. 5 showing the stub case positioning mechanism prior to receiving therein a stub case ejected from the cannon breech. FIG. 7B is a sectional view taken along line 7--7 of FIG. 5 showing the stub case positioning mechanism after having received a stub case therein subsequent to ejection of the stub case from the cannon breech. FIG. 8 is a cross sectional view taken along line 8--8 of FIG. 5 showing the torsion bar used to store energy for ejecting the captured stub case from the stub case catcher. FIG. 9 is a cross sectional view as taken along line 9--9 of FIG. 5. FIG. 10 is a cross sectional view taken along line 10--10 of FIG. 5. FIG. 11A is a cross sectional view taken along line 11--11 of FIG. 5 showing the stub case entrapment mechanism prior to receiving therein a stub case ejected from the cannon breech. FIG. 11B is a cross sectional view taken along line 11--11 of FIG. 5 showing the stub case entrapment mechanism after having captured a stub case therein subsequent to ejection of the stub case from the cannon breech. FIG. 11C is a cross sectional view taken along line 11--11 of of FIG. 5 showing the stub case entrapment mechanism ejecting the captured stub case from the catcher. FIG. 12 is a cross sectional view taken along line 12--12 of FIG. 1. FIG. 13 is a cross sectional view taken along line 13--13 of FIG. 1. FIG. 14 is an elevational view taken along line 14--14 of FIG. 11A. FIG. 15 diagrammatically illustrates one simple mechanism for triggering the catcher's ejection mechanism for ejection of the stub case from the catcher. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 through 3, a heavy cannon 10, as typically used in a modern day military tank, is partially shown having my stub case catcher mechanism 15 installed upon the breech 30 thereof. The catcher 15 basically comprises a trap housing 41 for trapping the stub case therein. The trap housing 41 is supported, to the rear of the breech 30, by lift arm 11 piviotly affixed to the right side of breech 30 by pivot 13 and locking arm 21 piviotly affixed to the left side of breech 30 by pivot 23. Lift arm 11, locking arm 21, and the centerline of trap assembly 15 are generally aligned with the centerline of barrel 56. Ejection door 16, closing off the rear opening of trap housing 41, is hingedly affixed to the catcher assembly 15 as described below. Referring now to FIG. 1, lift arm 11 is provided with an offset camming arm 14 having an offset camming slot 18 therein. Affixed generally to the frame of the weapon is hydraulic lifting cylinder 19 having a cam follower 20 attached to the cylinder's actuation rod 25. When cylinder 19 is hydraulically pressurized, rod 25 extends rearward (to the left as viewed in FIG. 1) advancing the cam follower 20 rearwardly into camming slot 18 until engagement with the slanted portion 26 of camming slot 18. As actuation rod 25 advances further, lift arm 11 is caused to pivot about pivot 13 and rise, as shown in FIG. 4B and 4C, thereby elevating catcher 15 above breech 30 thus permitting loading of an ammunition round into the cannon's breech. Similarly, as the activation rod 25 is retracted into cylinder 19 catcher 15 is lowered into alignment with breech 30. Because of the extremely high "G" loads created by the cannon's recoil action upon firing of a round, it is necessary that cylinder 19 be mounted to the weapon's frame. Thus the horizontal portion 27, of camming slot 18, permits axial translation of lift arm 11 with respect to cylinder 19 when cannon 10 recoils. Referring now to FIG. 2. Ejection door 16 is provided with pivot 28 axially parallel to and spaced to the rear of the door hinge. Piviotly connected to pivot 28 is door activation link 22 having its opposite end thereof piviotly connected to breech 30 by pivot 29. As catcher 15 is raised, by action of hydraulic cylinder 19 described above, door link 22 causes clockwise rotation of ejection door 16 about its hinge centerline 60, thereby opening the rear of trap housing 41, as seen in FIGS. 4B and 4C, thus permitting ejection of the entrapped stub casing therein as will be subsequently described in greater detail below. Having generally described the primary structure of my stub case catcher and now referring to FIGS. 4A, 4B, and 4C, the overall operational sequence will be described. FIG. 4A is intended to show my stub case catcher 15 in the weapon firing and stub case receiving position. The center line of catcher 15 is aligned with the weapon's barrel centerline (not shown) and is retained in this position during firing of the ammunition round and the resulting recoil of the weapon. Subsequent to firing of the ammunition round the stub case 50, shown in silhouette in FIGS. 4A and 4B, is ejected rearward from the breech 30, as depicted by arrow 51 and is caught and mechanically trapped within trap housing 41 as is described in greater detail below. The stub case enters the trap housing 41 with a significant amount of kinetic energy and is stopped by impacting against trap door 16. The kinetic energy of the stub case is thus absorbed and/or dissipated by transfer of the impacting force through pivot 28 and into door link 22 causing door link 22 to yield thereby absorbing the kinetic energy transfer from the stub case. After the stub case 50 is secured within trap housing 41 hydraulic cylinder 19 is activated thereby raising catcher 15 to the position as shown in FIG. 4B. It is preferred that the angle between the catcher centerline and that of gun barrel 56 be within the range of 35 to 45 degrees, and most preferably 40 degrees. Once catcher 15 is in the raised or eject position, as shown in FIG. 4B, stub case 50 is ejected from the catcher, through an appropriately aligned and open vehicle hatch (not shown). While in the raised position and before, during or after stub case ejection, a new ammunition round 52 is loaded into the cannon breech 30, preferably by an automatic ammunition loader. Subsequent to reloading of breech 30 and ejection of stub case 50 from catcher 15, hydraulic cylinder 19 is reverse activated thereby lowering the stub case catcher 15 to its firing position as shown in FIG. 4A and the cycle is repeated. Because of the extremely high "G" loading experienced by cannon 10 during its recoil, it is desirable to rigidly affix the stub case catcher to breech 30 during firing and recoil of the weapon. FIG. 12 shows a cross section of a spring loaded stop pin positioned within the left lift arm 11. As the catcher is lowered from its raised position (FIG. 4B and 4C) into the firing position (FIG. 4A) stop pin 39, biased into sliding engagement with the external side wall 44 of breech 30 by compression spring 38, slides along wall 44 of breech 30 until contact is made with ledge 34 thereby stopping further downward travel of the catcher 15. Catcher 15 is now in the firing position. Referring now to FIG. 13, it is also seen that as catcher 15 is lowered to the firing position, locking pin 35, also biased into sliding contact with the external wall 44 of breech 30 by compression spring 36, is caused to cam upon camming surface 33 thereby causing locking pin 35 to retract into bore 43 until aligned with bore 42 of breech 30. Locking pin 35 is then urged into bore 42 (as shown in FIG. 13) by action of compression spring 36 thereby locking lift arm 11, and catcher 15, to breech 30. It is to be appreciated that a similar stop pin and locking pin mechanism is also provided on the left side of breech 30 thereby simultaneously locking lift arm 21 to breech 30. Thus by action of the two lift arm locking pins and pivots 13 and 23, catcher 15 is made fast to breech 30 for the recoil portion of the weapon firing sequence. After the ammunition round is fired from the weapon, breech block 31 retracts downward from the breech (see FIGS. 4A, 4B, and 4C). As seen in FIG. 13 as breech block 31 translates downward camming surface 32 causes release pin 37 to retract into bore 42 thereby forcing locking pin 35 to retract into bore 43 thereby releasing lift arm 11. FIG. 5 presents an end elevation of the stub case catcher 15 assembly showing, in partial cutaway, the stub case alignment assembly 70, the stub case entrapment and ejection assembly 80, and the stub case ejection release mechanism 90. Referring to FIGS. 5, 7A and 7B, the catcher trap housing 41 is provided with three equally spaced stub case alignment mechanisms 70 as shown in FIGS. 7A and 7B. The alignment mechanisms 70 comprises a guide shoe 72 pivoted about pivot 74. Guide shoe 72 is biased radially inward toward the catcher centerline by compression spring 76 urging plunger 75 into contact with the guide shoe. Axially down stream (to the left in FIG. 7A) from guide shoe 72 is stub case centering cam 73 also biased radially inward toward the catcher centerline by compression spring 77. As stub case 50 enters the catcher housing 41, the three equally spaced guide shoes act to center the stub case within the trap housing 41 and align the stub case flange with the entrance ramp 54 of centering cam 73. As the stub case flange 53 proceeds rearward, stub case flange 53, acting upon the centering cam ramp 54, forces the centering cam into it's recess against compression spring 77. The rearward travel of stub case 50 is ultimately stopped by ejector door 16, as described above, thereby positioning stub case flange 57 upon centering cam 73 as shown in FIG. 7B. Stub case 50 is now centered within trap housing 41. At least one of the three stub case alignment mechanisms further includes an electrical switch to signal a central controller that the stub case is properly positioned within catcher 15. FIGS. 7A and 7B show an electrical switch comprising a simple cantilevered spring steel switch arm 79 which is in electrical contact with terminal 78, as shown in FIG. 7A, when no stub case is present within the trap housing 41. When stub case 50 is positioned within trap housing 41, as shown in FIG. 7B, plunger assembly 69 acts against switch 79, breaking the electrical circuit with terminal 78 and thereby providing a signal that the stub case is positioned within the trap housing 41. By having three such switches it may be easily determined if the stub case is properly positioned for ejection or askew. Referring now to FIG. 8 presenting a cross sectional view as taken along line 8--8 of FIG. 5 showing the torque transfer shaft 81 which also acts as the hinge for rotation of ejection door 16 about door hinge center line 60. Transfer shaft 81 is journaled within bore 88, passing through trap housing 41, by bearings 82 positioned at each end thereof. Ejection door 16 is hinged about the torque transfer shaft 81 as shown in FIG. 8. Passing through bore 89 of torque transfer shaft 81 is torsion bar 85 having square end zones 86 and 87. Square end zones 86 and 87 are received within square bores 93 and 94 within torsion arm 17 and the torque transfer shaft 81 as shown in FIG. 8. Torsion arm 17 is received within bearing 83, as shown in FIG. 8 and is retained within bore 96 by action of retention pin 84; thus torsion bar 85 is free to thermally expand and contract in the axial direction. It can now be appreciated that as the stub case catcher 15 is raised from the firing position, as shown in FIG. 4A, to the stub case rejection position, as shown in FIG. 4B by action of hydraulic cylinder 19, torsion bar 85 is torqued or twisted in the counter clockwise direction, as viewed in FIGS. 1, 4A, 4B, and 4C by action of the square ends 86 and 87 and torsion link 12, thereby storing potential energy therein. The square end 87 of torsion bar 85 and torque transfer shaft 81 are restricted from rotation as will be described below. Referring now to FIGS. 2, 5, 8, 9 and 10, rotatably positioned upon the end of the torque transfer shaft 81 is trip cam 24 biased clockwise, as viewed in FIG. 2, by pin 62 and compression spring 63 within a convenient bore within trap housing 41. Maximum clockwise travel of trip cam 24 is checked by the action of tang 97 acting upon abutment 99 of trap housing 41. Trip cam 24 is free to rotate about the torque transfer shaft 81 and serves to release stored energy within torsion bar 85 for ejection of stub case 50 from catcher 15 as will be further described below. Machined into the torque transfer shaft 81, as an integral part thereof and juxtaposed to trip cam 24, is torque release arm 100. Within the extended portion of torque release arm 100 is a cylindrical aperture 101 receiving therein plunger 57 biased to to the left, as viewed in FIG. 5, by compression spring 58 both of which are positioned within an appropriate bore within trap housing 41. Positioned axially in line with plunger 57 is camming ball 61 which is in rolling contact with cam surface 98 of trip cam 24. It can be appreciated, by reference to the figures, that as trip cam 24 is made to rotate counterclockwise, as viewed in FIG. 2, that camming ball 61 is thereby driven axially into aperture 64 driving plunger 57 axially into its bore. When the axial end of plunger 57 aligns with the surface or face of torque release arm 100 the torque release arm 100 is free to rotate relative to the trap housing 41 and trip cam 24. Thus torsion bar 85 is freed to rotate about its axis 60. By this release mechanism the energy stored within torsion bar 85 by raising the catcher 15 to its raised position, as shown in FIG. 4B may be released causing clockwise rotation of torque transfer shaft 81 as viewed in FIG. 2. This clockwise rotation of torque transfer shaft provides the motive force for ejection of the stub case as will be described below. Referring now to FIGS. 5, 6, 8, 11A through 11C and 14 showing details of the preferred stub case ejector mechanism 80. Ejector arm 101 is attached to the torque transfer shaft 81 by means of splines 92 projecting into groove 91 of torque transfer shaft 81 as shown in FIG. 6. Pivotly attached to ejector arm 101 by pivot 105 is ejector pawl 102 having a camming profile 106, best shown in FIG. 11A through 11C. Pawl 102 is biased radially inward, toward the weapon center line by compression spring 108 acting upon cap 107. After firing of the ammunition round and ejection of stub case 50 from breech 30, stub case 50 enters catcher 15 and is centered by action of the stub case alignment mechanisms 70 as described above. Stub case 50 progresses rearward over the pawl camming profile 106 thereby forcing pawl 102 to retract, against the force of compression spring 108, into offset 109 of ejector arm 101 thereby permitting passage of flange 53. After passage of flange 53, compression spring 108, in combination with cap 107, causes pawl 102 to entrap the stub case 50 between pawl 102 and ejector door 16 as shown in FIG. 11B. As catcher 15 is raised into the ejection position (FIG. 4B) torsion bar 85 is twisted thereby storing potential energy therein as described above. Upon release of torque transfer shaft 81 by action of trip cam 24, as described above, the potential energy stored within torsion bar 85 is transferred to torque transfer shaft 81 through square end 87 thereby causing the torque transfer shaft 81 to suddenly rotate counter clockwise, as viewed in FIGS. 9 and 10. As shown in FIG. 11C ejector arm 101 is thus caused to rotate in unison with the torque transfer shaft 81, to the left as viewed in FIG. 11C, thereby ejecting stub case 50 from catcher 15. FIG. 15 illustrates a simple linkage mechanism for the activation of trip cam 24. Cylinder 110 affixed to the roof of the tank turret (not shown) is hydraulically activated thereby causing link 112 to pivot clockwise about pivot 115 thus rotating trip cam 24 counter clockwise thereby releasing the torque transfer shaft 81, as described above, resulting in ejection of the stub case trapped within the catcher as described immediately above. In accordance with the provisions of the patent statutes, the principle and mode of operation of the invention have been illustrated and described in what is considered to represent its preferred embodiment. However, it should be understood that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.
The present invention generally relates to a military cannon as typically unted within the turret of a military armored vehicle such as an armored tank. My invention teaches method and apparatus for the catching and entrapping the stub case typically ejected from the breech of a military cannon after firing of an ammunition round. Subsequent to entrapment of the ejected stub case, the stub case catcher is raised to a preferred elevated angle simultaneously storing potential energy within a torsion bar which upon later release, ejects the entrapped stub case from the catcher and from the vehicle. By use of my invention and an automatic ammunition loader the crew requirements of such fighting vehicles may be reduced by eliminating the need for a human loader.
Briefly describe the main idea outlined in the provided context.
[ "The invention described herein may be manufactured, used and licensed by or for the Government for Governmental purposes without the payment to me of any royalties thereon.", "BACKGROUND OF THE INVENTION The present invention relates to a military tank/turret weapon system.", "At the present time a typical military tank combat crew consists of a tank commander, a driver, a gunner and an ammunition loader.", "The tank commander is the officer in command of the fighting vehicle and responsible for coordinating the functions and activities of the other crew members to successfully complete the vehicle's assigned mission.", "The driver is responsible for the operation of the vehicle's engine systems and generally driving or otherwise maneuvering the vehicle.", "The gunner is responsible for operation of the vehicle's weapon systems, tracking and targeting of enemy vehicles and firing the on board weapon system thereby destroying enemy vehicles.", "The ammunition loader is responsible for physically selecting the particular type of ammunition ordered by the tank commander to be fired and manually loading the chosen ammunition into the weapon.", "Upon firing of the round, the round's cartridge case (stub case) is ejected by the weapon's breech mechanism with a force sufficient to propel the stub case toward the rear of the tank turret where it is generally received within a holding container.", "However, many times the stub case does not land within the holding container and the loader must manually capture the case and deposit it within the holding container.", "Further as the holding container fills with ejected casings, the loader must dispose of the spent casings by manually tossing the ejected stub cases outside the tank turret.", "Future military tank cannon vehicle systems are being designed with a combat crew of three, the commander, driver, and gunner.", "The ammunition loader being replaced by an automated and mechanical loading device having a high rate of fire otherwise not achievable by a human loader.", "The stub case ejected from the weapon's breech must now be disposed of mechanically.", "SUMMARY OF THE PRESENT INVENTION The present invention teaches method and apparatus whereby the ammunition stub case, ejected from the breech of a tank turret cannon, may be safely and securely captured and subsequently ejected from the tank turret.", "A stub case catcher mechanism is herein taught that receives and traps therein the ejected stub case ejected from the breech of a typical cannon type weapon system.", "The stub case catcher decelerates the stub case, absorbing it's kinetic energy thereby stopping the stub case and securing it within the catcher.", "Once secured within the catcher, the catcher is raised to an inclined position from which the stub case may be physically ejected from the tank turret.", "As the catcher is raised to the ejection position energy is stored within a torsion bar later to be released thereby providing the necessary force and energy for ejecting the stub case from the vehicle.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a right side elevational view of my stub case catcher as typically mounted upon the breech of a military cannon.", "FIG. 2 is a left side elevational view of my stub case catcher.", "FIG. 3 is a top plan view showing my stub case catcher as attached to a typical weapon system.", "FIG. 4A illustrates my stub case catcher as mounted upon a typical cannon in the weapon firing position and ready to receive the stub case when ejected from the cannon breech.", "FIG. 4B illustrates the stub case catcher in its raised position subsequent to capturing therein a stub case ejected from the cannon breech.", "FIG. 4C illustrates the captured stub case being ejected from the stub case catcher and a new round of ammunition being simultaneously loaded into the cannon breech.", "FIG. 5 elevational view of my stub case catcher showing the general cation of various mechanical subassemblies.", "FIG. 6 is a sectional view taken along line 6--6 of FIG. 8. FIG. 7A is a cross sectional view taken along line 7--7 of FIG. 5 showing the stub case positioning mechanism prior to receiving therein a stub case ejected from the cannon breech.", "FIG. 7B is a sectional view taken along line 7--7 of FIG. 5 showing the stub case positioning mechanism after having received a stub case therein subsequent to ejection of the stub case from the cannon breech.", "FIG. 8 is a cross sectional view taken along line 8--8 of FIG. 5 showing the torsion bar used to store energy for ejecting the captured stub case from the stub case catcher.", "FIG. 9 is a cross sectional view as taken along line 9--9 of FIG. 5. FIG. 10 is a cross sectional view taken along line 10--10 of FIG. 5. FIG. 11A is a cross sectional view taken along line 11--11 of FIG. 5 showing the stub case entrapment mechanism prior to receiving therein a stub case ejected from the cannon breech.", "FIG. 11B is a cross sectional view taken along line 11--11 of FIG. 5 showing the stub case entrapment mechanism after having captured a stub case therein subsequent to ejection of the stub case from the cannon breech.", "FIG. 11C is a cross sectional view taken along line 11--11 of of FIG. 5 showing the stub case entrapment mechanism ejecting the captured stub case from the catcher.", "FIG. 12 is a cross sectional view taken along line 12--12 of FIG. 1. FIG. 13 is a cross sectional view taken along line 13--13 of FIG. 1. FIG. 14 is an elevational view taken along line 14--14 of FIG. 11A.", "FIG. 15 diagrammatically illustrates one simple mechanism for triggering the catcher's ejection mechanism for ejection of the stub case from the catcher.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 through 3, a heavy cannon 10, as typically used in a modern day military tank, is partially shown having my stub case catcher mechanism 15 installed upon the breech 30 thereof.", "The catcher 15 basically comprises a trap housing 41 for trapping the stub case therein.", "The trap housing 41 is supported, to the rear of the breech 30, by lift arm 11 piviotly affixed to the right side of breech 30 by pivot 13 and locking arm 21 piviotly affixed to the left side of breech 30 by pivot 23.", "Lift arm 11, locking arm 21, and the centerline of trap assembly 15 are generally aligned with the centerline of barrel 56.", "Ejection door 16, closing off the rear opening of trap housing 41, is hingedly affixed to the catcher assembly 15 as described below.", "Referring now to FIG. 1, lift arm 11 is provided with an offset camming arm 14 having an offset camming slot 18 therein.", "Affixed generally to the frame of the weapon is hydraulic lifting cylinder 19 having a cam follower 20 attached to the cylinder's actuation rod 25.", "When cylinder 19 is hydraulically pressurized, rod 25 extends rearward (to the left as viewed in FIG. 1) advancing the cam follower 20 rearwardly into camming slot 18 until engagement with the slanted portion 26 of camming slot 18.", "As actuation rod 25 advances further, lift arm 11 is caused to pivot about pivot 13 and rise, as shown in FIG. 4B and 4C, thereby elevating catcher 15 above breech 30 thus permitting loading of an ammunition round into the cannon's breech.", "Similarly, as the activation rod 25 is retracted into cylinder 19 catcher 15 is lowered into alignment with breech 30.", "Because of the extremely high "G"", "loads created by the cannon's recoil action upon firing of a round, it is necessary that cylinder 19 be mounted to the weapon's frame.", "Thus the horizontal portion 27, of camming slot 18, permits axial translation of lift arm 11 with respect to cylinder 19 when cannon 10 recoils.", "Referring now to FIG. 2. Ejection door 16 is provided with pivot 28 axially parallel to and spaced to the rear of the door hinge.", "Piviotly connected to pivot 28 is door activation link 22 having its opposite end thereof piviotly connected to breech 30 by pivot 29.", "As catcher 15 is raised, by action of hydraulic cylinder 19 described above, door link 22 causes clockwise rotation of ejection door 16 about its hinge centerline 60, thereby opening the rear of trap housing 41, as seen in FIGS. 4B and 4C, thus permitting ejection of the entrapped stub casing therein as will be subsequently described in greater detail below.", "Having generally described the primary structure of my stub case catcher and now referring to FIGS. 4A, 4B, and 4C, the overall operational sequence will be described.", "FIG. 4A is intended to show my stub case catcher 15 in the weapon firing and stub case receiving position.", "The center line of catcher 15 is aligned with the weapon's barrel centerline (not shown) and is retained in this position during firing of the ammunition round and the resulting recoil of the weapon.", "Subsequent to firing of the ammunition round the stub case 50, shown in silhouette in FIGS. 4A and 4B, is ejected rearward from the breech 30, as depicted by arrow 51 and is caught and mechanically trapped within trap housing 41 as is described in greater detail below.", "The stub case enters the trap housing 41 with a significant amount of kinetic energy and is stopped by impacting against trap door 16.", "The kinetic energy of the stub case is thus absorbed and/or dissipated by transfer of the impacting force through pivot 28 and into door link 22 causing door link 22 to yield thereby absorbing the kinetic energy transfer from the stub case.", "After the stub case 50 is secured within trap housing 41 hydraulic cylinder 19 is activated thereby raising catcher 15 to the position as shown in FIG. 4B.", "It is preferred that the angle between the catcher centerline and that of gun barrel 56 be within the range of 35 to 45 degrees, and most preferably 40 degrees.", "Once catcher 15 is in the raised or eject position, as shown in FIG. 4B, stub case 50 is ejected from the catcher, through an appropriately aligned and open vehicle hatch (not shown).", "While in the raised position and before, during or after stub case ejection, a new ammunition round 52 is loaded into the cannon breech 30, preferably by an automatic ammunition loader.", "Subsequent to reloading of breech 30 and ejection of stub case 50 from catcher 15, hydraulic cylinder 19 is reverse activated thereby lowering the stub case catcher 15 to its firing position as shown in FIG. 4A and the cycle is repeated.", "Because of the extremely high "G"", "loading experienced by cannon 10 during its recoil, it is desirable to rigidly affix the stub case catcher to breech 30 during firing and recoil of the weapon.", "FIG. 12 shows a cross section of a spring loaded stop pin positioned within the left lift arm 11.", "As the catcher is lowered from its raised position (FIG.", "4B and 4C) into the firing position (FIG.", "4A) stop pin 39, biased into sliding engagement with the external side wall 44 of breech 30 by compression spring 38, slides along wall 44 of breech 30 until contact is made with ledge 34 thereby stopping further downward travel of the catcher 15.", "Catcher 15 is now in the firing position.", "Referring now to FIG. 13, it is also seen that as catcher 15 is lowered to the firing position, locking pin 35, also biased into sliding contact with the external wall 44 of breech 30 by compression spring 36, is caused to cam upon camming surface 33 thereby causing locking pin 35 to retract into bore 43 until aligned with bore 42 of breech 30.", "Locking pin 35 is then urged into bore 42 (as shown in FIG. 13) by action of compression spring 36 thereby locking lift arm 11, and catcher 15, to breech 30.", "It is to be appreciated that a similar stop pin and locking pin mechanism is also provided on the left side of breech 30 thereby simultaneously locking lift arm 21 to breech 30.", "Thus by action of the two lift arm locking pins and pivots 13 and 23, catcher 15 is made fast to breech 30 for the recoil portion of the weapon firing sequence.", "After the ammunition round is fired from the weapon, breech block 31 retracts downward from the breech (see FIGS. 4A, 4B, and 4C).", "As seen in FIG. 13 as breech block 31 translates downward camming surface 32 causes release pin 37 to retract into bore 42 thereby forcing locking pin 35 to retract into bore 43 thereby releasing lift arm 11.", "FIG. 5 presents an end elevation of the stub case catcher 15 assembly showing, in partial cutaway, the stub case alignment assembly 70, the stub case entrapment and ejection assembly 80, and the stub case ejection release mechanism 90.", "Referring to FIGS. 5, 7A and 7B, the catcher trap housing 41 is provided with three equally spaced stub case alignment mechanisms 70 as shown in FIGS. 7A and 7B.", "The alignment mechanisms 70 comprises a guide shoe 72 pivoted about pivot 74.", "Guide shoe 72 is biased radially inward toward the catcher centerline by compression spring 76 urging plunger 75 into contact with the guide shoe.", "Axially down stream (to the left in FIG. 7A) from guide shoe 72 is stub case centering cam 73 also biased radially inward toward the catcher centerline by compression spring 77.", "As stub case 50 enters the catcher housing 41, the three equally spaced guide shoes act to center the stub case within the trap housing 41 and align the stub case flange with the entrance ramp 54 of centering cam 73.", "As the stub case flange 53 proceeds rearward, stub case flange 53, acting upon the centering cam ramp 54, forces the centering cam into it's recess against compression spring 77.", "The rearward travel of stub case 50 is ultimately stopped by ejector door 16, as described above, thereby positioning stub case flange 57 upon centering cam 73 as shown in FIG. 7B.", "Stub case 50 is now centered within trap housing 41.", "At least one of the three stub case alignment mechanisms further includes an electrical switch to signal a central controller that the stub case is properly positioned within catcher 15.", "FIGS. 7A and 7B show an electrical switch comprising a simple cantilevered spring steel switch arm 79 which is in electrical contact with terminal 78, as shown in FIG. 7A, when no stub case is present within the trap housing 41.", "When stub case 50 is positioned within trap housing 41, as shown in FIG. 7B, plunger assembly 69 acts against switch 79, breaking the electrical circuit with terminal 78 and thereby providing a signal that the stub case is positioned within the trap housing 41.", "By having three such switches it may be easily determined if the stub case is properly positioned for ejection or askew.", "Referring now to FIG. 8 presenting a cross sectional view as taken along line 8--8 of FIG. 5 showing the torque transfer shaft 81 which also acts as the hinge for rotation of ejection door 16 about door hinge center line 60.", "Transfer shaft 81 is journaled within bore 88, passing through trap housing 41, by bearings 82 positioned at each end thereof.", "Ejection door 16 is hinged about the torque transfer shaft 81 as shown in FIG. 8. Passing through bore 89 of torque transfer shaft 81 is torsion bar 85 having square end zones 86 and 87.", "Square end zones 86 and 87 are received within square bores 93 and 94 within torsion arm 17 and the torque transfer shaft 81 as shown in FIG. 8. Torsion arm 17 is received within bearing 83, as shown in FIG. 8 and is retained within bore 96 by action of retention pin 84;", "thus torsion bar 85 is free to thermally expand and contract in the axial direction.", "It can now be appreciated that as the stub case catcher 15 is raised from the firing position, as shown in FIG. 4A, to the stub case rejection position, as shown in FIG. 4B by action of hydraulic cylinder 19, torsion bar 85 is torqued or twisted in the counter clockwise direction, as viewed in FIGS. 1, 4A, 4B, and 4C by action of the square ends 86 and 87 and torsion link 12, thereby storing potential energy therein.", "The square end 87 of torsion bar 85 and torque transfer shaft 81 are restricted from rotation as will be described below.", "Referring now to FIGS. 2, 5, 8, 9 and 10, rotatably positioned upon the end of the torque transfer shaft 81 is trip cam 24 biased clockwise, as viewed in FIG. 2, by pin 62 and compression spring 63 within a convenient bore within trap housing 41.", "Maximum clockwise travel of trip cam 24 is checked by the action of tang 97 acting upon abutment 99 of trap housing 41.", "Trip cam 24 is free to rotate about the torque transfer shaft 81 and serves to release stored energy within torsion bar 85 for ejection of stub case 50 from catcher 15 as will be further described below.", "Machined into the torque transfer shaft 81, as an integral part thereof and juxtaposed to trip cam 24, is torque release arm 100.", "Within the extended portion of torque release arm 100 is a cylindrical aperture 101 receiving therein plunger 57 biased to to the left, as viewed in FIG. 5, by compression spring 58 both of which are positioned within an appropriate bore within trap housing 41.", "Positioned axially in line with plunger 57 is camming ball 61 which is in rolling contact with cam surface 98 of trip cam 24.", "It can be appreciated, by reference to the figures, that as trip cam 24 is made to rotate counterclockwise, as viewed in FIG. 2, that camming ball 61 is thereby driven axially into aperture 64 driving plunger 57 axially into its bore.", "When the axial end of plunger 57 aligns with the surface or face of torque release arm 100 the torque release arm 100 is free to rotate relative to the trap housing 41 and trip cam 24.", "Thus torsion bar 85 is freed to rotate about its axis 60.", "By this release mechanism the energy stored within torsion bar 85 by raising the catcher 15 to its raised position, as shown in FIG. 4B may be released causing clockwise rotation of torque transfer shaft 81 as viewed in FIG. 2. This clockwise rotation of torque transfer shaft provides the motive force for ejection of the stub case as will be described below.", "Referring now to FIGS. 5, 6, 8, 11A through 11C and 14 showing details of the preferred stub case ejector mechanism 80.", "Ejector arm 101 is attached to the torque transfer shaft 81 by means of splines 92 projecting into groove 91 of torque transfer shaft 81 as shown in FIG. 6. Pivotly attached to ejector arm 101 by pivot 105 is ejector pawl 102 having a camming profile 106, best shown in FIG. 11A through 11C.", "Pawl 102 is biased radially inward, toward the weapon center line by compression spring 108 acting upon cap 107.", "After firing of the ammunition round and ejection of stub case 50 from breech 30, stub case 50 enters catcher 15 and is centered by action of the stub case alignment mechanisms 70 as described above.", "Stub case 50 progresses rearward over the pawl camming profile 106 thereby forcing pawl 102 to retract, against the force of compression spring 108, into offset 109 of ejector arm 101 thereby permitting passage of flange 53.", "After passage of flange 53, compression spring 108, in combination with cap 107, causes pawl 102 to entrap the stub case 50 between pawl 102 and ejector door 16 as shown in FIG. 11B.", "As catcher 15 is raised into the ejection position (FIG.", "4B) torsion bar 85 is twisted thereby storing potential energy therein as described above.", "Upon release of torque transfer shaft 81 by action of trip cam 24, as described above, the potential energy stored within torsion bar 85 is transferred to torque transfer shaft 81 through square end 87 thereby causing the torque transfer shaft 81 to suddenly rotate counter clockwise, as viewed in FIGS. 9 and 10.", "As shown in FIG. 11C ejector arm 101 is thus caused to rotate in unison with the torque transfer shaft 81, to the left as viewed in FIG. 11C, thereby ejecting stub case 50 from catcher 15.", "FIG. 15 illustrates a simple linkage mechanism for the activation of trip cam 24.", "Cylinder 110 affixed to the roof of the tank turret (not shown) is hydraulically activated thereby causing link 112 to pivot clockwise about pivot 115 thus rotating trip cam 24 counter clockwise thereby releasing the torque transfer shaft 81, as described above, resulting in ejection of the stub case trapped within the catcher as described immediately above.", "In accordance with the provisions of the patent statutes, the principle and mode of operation of the invention have been illustrated and described in what is considered to represent its preferred embodiment.", "However, it should be understood that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope." ]
BRIEF DESCRIPTION The subject invention is a portable, multiple lamp, fluorescent work light encased in a durable, light-weight tubular case employing resilient end caps. The tubular shell and the resilient end caps, when tied together with a single structural rod, form a strong, durable structure which can be opened by unscrewing just one external nut. The resilient end caps serve the multiple purposes of; I) forming a strong, tight seal between the tubular shell and other external components, II) allowing easy disassembly or assembly of the enhanced portable work light and III) absorbing shocks from falls or other impacts as well as protecting external parts such as a power cord strain relief and power switch from direct impacts. The resilient end caps combine these three features in such a way that the end caps and structure of the invention are durable, light weight and compact. The invention is typically used in work or construction sites where a considerable amount of temporary, rugged lighting needs to be deployed rapidly. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an external view of the enhanced portable work light. FIG. 2 shows how the resilient end cap 6 can be removed from the enhanced portable work light without disconnecting internal wiring 22, by pushing the external disk 5 through the internal slots 19 of the resilient end cap 6. The external disk 5 is sized smaller than the inside diameter of tubular shell 8 to allow tubular shell 8 to slide past external disk 5 and internal components of the light. FIG. 3 shows an exploded cross sectional side view of the invention showing major components of the invention's structure. FIG. 3 also shows how the external disks 5 and 13, resilient end caps 6, structural rod 7, and tubular shell 8 are assembled. Dashed lines indicate the direction of assembly for exterior items. Where a number such as 6 points to two different images, the upper image is a side view, and the lower image is an end view of the same object. FIG. 4 shows an assembled, cross sectional, side view of the invention. DETAILED DESCRIPTION OF THE INVENTION A typical use of the invention would be in a construction or similar type of work environment where the light will be used on a temporary basis or where lights must be moved frequently. A typical application would be inside an airplane during its construction. The invention typically includes a power cord 2 with plug 14 at one end and a power receptacle 1 at the other end such that several enhanced portable work lights can be plugged together to form a string of work lights. Prior art fluorescent work lights were most commonly a single lamp unit in a clear tubular shell which used the shell as an attachment point to hold the end caps 6 in place. Prior art multiple lamp, fluorescent work lights, capable of similar light Lumen output and impact resistance when compared with the invention, have weighed significantly more. The invention differs from prior art in that it uses a circular or near circular cross section tubular shell 8 combined with multipurpose resilient end caps 6 which when tied together with a single, hollow structural rod 7 which travels inside the tubular shell 8 between each of the resilient end caps 6, ties the supporting structural components of the light together in a light weight, strong, and durable package. Construction with the single structural rod 7 allows the light to be opened by means of unscrewing only one large nut 4 threaded onto the end of the structural rod. The electrical 9,10,11 and lamp 15 components are connected to the structural rod. The resilient end cap 6, and the way that it is used in the construction of the enhanced portable work light, is unique in that it provides three separate functions in one compact piece. The integration of any two or all three of these functions into one piece provides an additional benefit in reduced weight, material cost, and production cost for the resilient end cap and enhanced portable work light. The three functions provided by the resilient end cap (REC) 6 are: I) The REC enables a strong, tightly fitting, seal between the external disk and the tubular shell 8 of the enhanced portable work light even though the external disk is smaller in diameter than the inside diameter of the tubular shell. The external disk 5,13 is smaller in diameter than the tubular shell 8 so that the tubular shell may slide over it as well as the rest of the light during assembly or disassembly. II) The external disk can be pushed sideways through the inside of the REC through internal slots 19. This feature allows the resilient end cap to be separated from the light without disconnecting internal wiring 22 attached to the external disk. This is accomplished by first loosening and removing the threaded, capped, nut 4 holding the external disk 5, 13 in position, pulling the external disk away from the REC, then flipping the external disk approximately 90 degrees such that its edges line up with internal slots 19 built into the inside of the REC, and finally, pushing the disc through the inside of the REC through internal slots 19 as shown in FIG. 2. The external disk 5, 13 is pushed through the inside of the REC in order to install or remove the REC from the light without disconnecting internal wiring 22 which is connected to the external disk. Since, as described above, the external disk 5, 13 fits inside the tubular shell 8, the tubular shell may slide on or off past the external disk internal components of the light without having to disconnect internal wiring 22 attached to the external disk. III) The REC has an integral resilient extension 17 which extends or flares radially around and beyond the external disk 5, 13 at the end of the enhanced portable work light in the same way that a skirt would extend or flare around and beyond a person's hip. The purpose of the resilient extension is twofold: first the resilient extension protects components attached to the external disks 5, 13 such as electrical cord strain reliefs 3 or power switches 12 from direct impacts, and secondly the resilient extension 17 serves to cushion the entire enhanced portable work light from impacts whether they are of the type from dropping the enhanced portable work light in a vertical or horizontal orientation. For impacts such as when the enhanced portable work light is dropped in a horizontal orientation, the flaring construction of the resilient extension ensures that the contact point, for an impact with a flat surface such as the floor, will be beyond the end of the tubular shell 8. A contact point at that location will give easier and therefore produce a softer cushioning with a more gradual deceleration, than a contact point closer to the tubular shell such as would happen if the resilient extension did not flare as described above. The above flaring construction therefore enables the REC to provide soft cushioning even when the REC is made of a stiffer or higher durometer material. The advantage of using a stiffer or higher durometer material is that the entire resilient end cap 6 can be constructed with less material to be lighter weight. The preferred material of construction for the resilient end cap 6 is an elastomer such as polyurethane in a durometer range of between 60 and 120 Shore A. The preferred plastic, for the tubular shell 8, is clear polycarbonate which has a very high impact strength relative to weight and size, and therefore allows a lighter weight construction. The tubular shell 8 can have grooves etched in it to defuse light. Additionally, tubular shell 8 can have an oval cross section. The preferred structural rod 7 which ties the resilient end caps 6 together is a hollow aluminum rod which is threaded at each end. The threaded portion of the structural rod 7 extends through external disks 5, 13 on each end of the enhanced portable work light. A threaded, capped, nut 4 can thread onto the end of the structural rod 7 compress and seal an external disk 5, 13 against the resilient end cap 6, which in turn presses and seals the resilient end cap 6 against the tubular shell 8 of the enhanced portable work light. By having a single external tightening mechanism at each end cap, the light can be assembled and disassembled rapidly. The hollow rod 7 also carries electrical wires inside it from one end of the light to the other. The preferred construction of the threaded nut 4 is a capped one made of plastic such that a watertight seal can be made by using an "O" ring between the nut 4 and the external disk 5, 13. The preferred construction of the invention includes watertight exterior electrical components such as cord strain relief, power plug, power receptacle, and power switch. One preferred construction for an enhanced portable work light is to use a quantity of four, four foot long fluorescent T8 lamps, spaced evenly around, and parallel to, the structural rod 7. Alternate constructions include 2, 3, 4, or 6 lamps in 2 foot, 3 foot, 4 foot, 5 foot, or 6 foot lengths. Lamps can be either T5, T8, T10, or T12 diameter size, bipin or single pin fluorescent lamps. The bipin sockets are attached to socket disks which are attached to the structural rod 7. To reduce the chance of improper rotation of one socket disk with respect to the other, the socket disks are made such that they are not radially symmetrical. Another preferred construction of the enhanced portable work light is to use two 22.5 inch long twin-tube compact fluorescent lamps. Alternate constructions include 2, 3, or 4 compact fluorescent bulbs of any length. A preferred construction is to mount a high efficiency, light-weight electronic solid state fluorescent ballast to the structural support rod 7 beyond the end of the lamps 15. The structural rod is notched to provide a flat surface onto which the ballast is mounted. A preferred construction is to incorporate a power cord 2 with a plug 14 connected to one end of the enhanced portable work light, and to incorporate a receptacle 1 attached to the other end of the light. The receptacle can be attached to a power cord 2 as well. Matching water tight plugs and receptacles can be used. The receptacle is wired directly to the power cord 2 so that two or more enhanced portable work lights can be plugged together to form a string of work lights. A preferred construction is to use two Velcro straps 16 to hang the enhanced portable work light which wrap around the light tight enough that straps 16 can not slip past resilient end caps 6, but attached loosely enough so that their position can be adjusted by sliding a strap 16 up or down the length of the tubular shell 8. A preferred construction is to put two large semicircular notches 18 in the flared extensions 17 on the resilient end cap 6. The notches are intended to decrease the chance of the flared extension landing on and pinching the power cord 2 when the enhanced portable work light is rested on its end in a near vertical orientation.
The subject invention is a portable, multiple lamp, fluorescent work light encased in a durable, light-weight tubular case employing resilient end caps. The tubular shell and the resilient end caps, when tied together with a single structural rod, form a strong, durable structure which can be opened by unscrewing just one external nut. The resilient end caps combine three different functions in one item such that weight, size and cost can be reduced. The invention is intended for work or construction sites where a considerable amount of temporary, rugged lighting needs to be deployed rapidly.
Summarize the key points of the given document.
[ "BRIEF DESCRIPTION The subject invention is a portable, multiple lamp, fluorescent work light encased in a durable, light-weight tubular case employing resilient end caps.", "The tubular shell and the resilient end caps, when tied together with a single structural rod, form a strong, durable structure which can be opened by unscrewing just one external nut.", "The resilient end caps serve the multiple purposes of;", "I) forming a strong, tight seal between the tubular shell and other external components, II) allowing easy disassembly or assembly of the enhanced portable work light and III) absorbing shocks from falls or other impacts as well as protecting external parts such as a power cord strain relief and power switch from direct impacts.", "The resilient end caps combine these three features in such a way that the end caps and structure of the invention are durable, light weight and compact.", "The invention is typically used in work or construction sites where a considerable amount of temporary, rugged lighting needs to be deployed rapidly.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an external view of the enhanced portable work light.", "FIG. 2 shows how the resilient end cap 6 can be removed from the enhanced portable work light without disconnecting internal wiring 22, by pushing the external disk 5 through the internal slots 19 of the resilient end cap 6.", "The external disk 5 is sized smaller than the inside diameter of tubular shell 8 to allow tubular shell 8 to slide past external disk 5 and internal components of the light.", "FIG. 3 shows an exploded cross sectional side view of the invention showing major components of the invention's structure.", "FIG. 3 also shows how the external disks 5 and 13, resilient end caps 6, structural rod 7, and tubular shell 8 are assembled.", "Dashed lines indicate the direction of assembly for exterior items.", "Where a number such as 6 points to two different images, the upper image is a side view, and the lower image is an end view of the same object.", "FIG. 4 shows an assembled, cross sectional, side view of the invention.", "DETAILED DESCRIPTION OF THE INVENTION A typical use of the invention would be in a construction or similar type of work environment where the light will be used on a temporary basis or where lights must be moved frequently.", "A typical application would be inside an airplane during its construction.", "The invention typically includes a power cord 2 with plug 14 at one end and a power receptacle 1 at the other end such that several enhanced portable work lights can be plugged together to form a string of work lights.", "Prior art fluorescent work lights were most commonly a single lamp unit in a clear tubular shell which used the shell as an attachment point to hold the end caps 6 in place.", "Prior art multiple lamp, fluorescent work lights, capable of similar light Lumen output and impact resistance when compared with the invention, have weighed significantly more.", "The invention differs from prior art in that it uses a circular or near circular cross section tubular shell 8 combined with multipurpose resilient end caps 6 which when tied together with a single, hollow structural rod 7 which travels inside the tubular shell 8 between each of the resilient end caps 6, ties the supporting structural components of the light together in a light weight, strong, and durable package.", "Construction with the single structural rod 7 allows the light to be opened by means of unscrewing only one large nut 4 threaded onto the end of the structural rod.", "The electrical 9,10,11 and lamp 15 components are connected to the structural rod.", "The resilient end cap 6, and the way that it is used in the construction of the enhanced portable work light, is unique in that it provides three separate functions in one compact piece.", "The integration of any two or all three of these functions into one piece provides an additional benefit in reduced weight, material cost, and production cost for the resilient end cap and enhanced portable work light.", "The three functions provided by the resilient end cap (REC) 6 are: I) The REC enables a strong, tightly fitting, seal between the external disk and the tubular shell 8 of the enhanced portable work light even though the external disk is smaller in diameter than the inside diameter of the tubular shell.", "The external disk 5,13 is smaller in diameter than the tubular shell 8 so that the tubular shell may slide over it as well as the rest of the light during assembly or disassembly.", "II) The external disk can be pushed sideways through the inside of the REC through internal slots 19.", "This feature allows the resilient end cap to be separated from the light without disconnecting internal wiring 22 attached to the external disk.", "This is accomplished by first loosening and removing the threaded, capped, nut 4 holding the external disk 5, 13 in position, pulling the external disk away from the REC, then flipping the external disk approximately 90 degrees such that its edges line up with internal slots 19 built into the inside of the REC, and finally, pushing the disc through the inside of the REC through internal slots 19 as shown in FIG. 2. The external disk 5, 13 is pushed through the inside of the REC in order to install or remove the REC from the light without disconnecting internal wiring 22 which is connected to the external disk.", "Since, as described above, the external disk 5, 13 fits inside the tubular shell 8, the tubular shell may slide on or off past the external disk internal components of the light without having to disconnect internal wiring 22 attached to the external disk.", "III) The REC has an integral resilient extension 17 which extends or flares radially around and beyond the external disk 5, 13 at the end of the enhanced portable work light in the same way that a skirt would extend or flare around and beyond a person's hip.", "The purpose of the resilient extension is twofold: first the resilient extension protects components attached to the external disks 5, 13 such as electrical cord strain reliefs 3 or power switches 12 from direct impacts, and secondly the resilient extension 17 serves to cushion the entire enhanced portable work light from impacts whether they are of the type from dropping the enhanced portable work light in a vertical or horizontal orientation.", "For impacts such as when the enhanced portable work light is dropped in a horizontal orientation, the flaring construction of the resilient extension ensures that the contact point, for an impact with a flat surface such as the floor, will be beyond the end of the tubular shell 8.", "A contact point at that location will give easier and therefore produce a softer cushioning with a more gradual deceleration, than a contact point closer to the tubular shell such as would happen if the resilient extension did not flare as described above.", "The above flaring construction therefore enables the REC to provide soft cushioning even when the REC is made of a stiffer or higher durometer material.", "The advantage of using a stiffer or higher durometer material is that the entire resilient end cap 6 can be constructed with less material to be lighter weight.", "The preferred material of construction for the resilient end cap 6 is an elastomer such as polyurethane in a durometer range of between 60 and 120 Shore A. The preferred plastic, for the tubular shell 8, is clear polycarbonate which has a very high impact strength relative to weight and size, and therefore allows a lighter weight construction.", "The tubular shell 8 can have grooves etched in it to defuse light.", "Additionally, tubular shell 8 can have an oval cross section.", "The preferred structural rod 7 which ties the resilient end caps 6 together is a hollow aluminum rod which is threaded at each end.", "The threaded portion of the structural rod 7 extends through external disks 5, 13 on each end of the enhanced portable work light.", "A threaded, capped, nut 4 can thread onto the end of the structural rod 7 compress and seal an external disk 5, 13 against the resilient end cap 6, which in turn presses and seals the resilient end cap 6 against the tubular shell 8 of the enhanced portable work light.", "By having a single external tightening mechanism at each end cap, the light can be assembled and disassembled rapidly.", "The hollow rod 7 also carries electrical wires inside it from one end of the light to the other.", "The preferred construction of the threaded nut 4 is a capped one made of plastic such that a watertight seal can be made by using an "O"", "ring between the nut 4 and the external disk 5, 13.", "The preferred construction of the invention includes watertight exterior electrical components such as cord strain relief, power plug, power receptacle, and power switch.", "One preferred construction for an enhanced portable work light is to use a quantity of four, four foot long fluorescent T8 lamps, spaced evenly around, and parallel to, the structural rod 7.", "Alternate constructions include 2, 3, 4, or 6 lamps in 2 foot, 3 foot, 4 foot, 5 foot, or 6 foot lengths.", "Lamps can be either T5, T8, T10, or T12 diameter size, bipin or single pin fluorescent lamps.", "The bipin sockets are attached to socket disks which are attached to the structural rod 7.", "To reduce the chance of improper rotation of one socket disk with respect to the other, the socket disks are made such that they are not radially symmetrical.", "Another preferred construction of the enhanced portable work light is to use two 22.5 inch long twin-tube compact fluorescent lamps.", "Alternate constructions include 2, 3, or 4 compact fluorescent bulbs of any length.", "A preferred construction is to mount a high efficiency, light-weight electronic solid state fluorescent ballast to the structural support rod 7 beyond the end of the lamps 15.", "The structural rod is notched to provide a flat surface onto which the ballast is mounted.", "A preferred construction is to incorporate a power cord 2 with a plug 14 connected to one end of the enhanced portable work light, and to incorporate a receptacle 1 attached to the other end of the light.", "The receptacle can be attached to a power cord 2 as well.", "Matching water tight plugs and receptacles can be used.", "The receptacle is wired directly to the power cord 2 so that two or more enhanced portable work lights can be plugged together to form a string of work lights.", "A preferred construction is to use two Velcro straps 16 to hang the enhanced portable work light which wrap around the light tight enough that straps 16 can not slip past resilient end caps 6, but attached loosely enough so that their position can be adjusted by sliding a strap 16 up or down the length of the tubular shell 8.", "A preferred construction is to put two large semicircular notches 18 in the flared extensions 17 on the resilient end cap 6.", "The notches are intended to decrease the chance of the flared extension landing on and pinching the power cord 2 when the enhanced portable work light is rested on its end in a near vertical orientation." ]
MICROFICHE APPENDIX A Microfiche Appendix comprising one sheet, totaling twenty-seven frames is included herewith. COPYRIGHT NOTICE A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the reproduction of the patent document or the patent disclosure in exactly the form it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. TECHNICAL FIELD The present invention relates to memory circuits for microprocessors. BACKGROUND OF THE INVENTION The operation of processors frequently involves temporary storage of information for later manipulation. As is well known, data may be stored for random access, or may be stored for access in an ordered fashion such as in a stack or queue. A queue stores data entries in sequential fashion, so that the oldest entry in the queue is retrieved first. The entry and removal of data in queues may be handled by a central processing unit (CPU) processing software instructions. Such a queue system can be a bottleneck in the efficient operation of the processor. For example, a first item of information obtained from one process may need to be queued to wait for the processing of another item of information, so that both items may then be manipulated together by the processor. The queuing and dequeuing of the first item of information may require additional work of the processor, slowing the eventual processing of both items of information further. More complicated situations involving multiple operands and operations cause the queuing and dequeuing complications to multiply, requiring various locks that absorb further processing power and time. The size and complexity of a microprocessor can lead to correspondingly large and complex arrangements for storing queues. The allocation of memory space for these queues is also challenging, as the queues can vary in length depending upon the type of operations being processed. For example, a queuing scheme for a communication system is described by Delp et al. in U.S. Pat. No. 5,629,933, in which a number of data packets are stored in first-in, first out (FIFO) order in queues that are segregated by session identity. Depending upon activity of a particular session, the number of entries in such queues could be very large or zero. In U.S. Pat. No. 5,097,442, Ward et al. teach programming a variable number into a register to store that number of data words in a FIFO memory array, up to the limited size of that array. To distribute memory for queuing different connections, U.S. Pat. No. 5,812,775 to Van Seters et al. teaches a device for a router having a number of network connections that dedicates specific buffers to each network connection as well as providing a pool of buffers for servicing any network connection. A number of static random access memory (SRAM) queues are maintained for tracking buffer usage and allocating buffers for storage. While SRAM provides relatively quick access compared to dynamic random access memory (DRAM), SRAM memory cells are much larger than DRAM, making SRAM relatively expensive in terms of chip real estate. SUMMARY OF THE INVENTION The present invention provides a mechanism for queuing information that is fast, flexible and efficient. The mechanism combines the speed of SRAM with the low cost and low power consumption of DRAM, to enable significant expansion of high-speed data storage in queues without corresponding increases in costs. The queues may be manipulated by hardware or software, and may provide processing events for an event-driven processor. While the queuing mechanism of the present invention can be employed in many systems in place of conventional queues, particular utility is found where high speed access to queues is beneficial, as well for situations in which flexible queue size may be an advantage, and/or for cases where the smaller size and lower cost of DRAM compared to SRAM is of value. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram of a plurality of queues of the present invention. FIG. 2 is a diagram of the enqueuing and dequeuing of entries in a queue of FIG. 1 . FIG. 3 is a diagram of a network computer implementation of the queue system of the present invention. FIG. 4 is a diagram of a plurality of status registers for the queues of FIG. 3 . FIG. 5 is a diagram of a queue manager that manages movement of queue entries between various queues in the queue system of FIG. 3 . FIG. 6 is a diagram of a queue system that may be provided on a card that plugs into a computer or other device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a plurality of hardware queues of the present invention, which may contain other such hardware queues as well. A first queue 20 is formed of a combination of SRAM 22 and DRAM 25 storage units. A second queue 27 is similarly formed as a combination of SRAM 30 and DRAM 25 storage units. The queues 20 and 27 each have an SRAM head and tail which can be used as an SRAM FIFO, and the ability to queue information in a DRAM body as well, allowing expansion and individual configuration of each queue. Connection between SRAM FIFOS 22 and 30 and DRAM 25 allows those queues 20 and 27 to handle situations in which the SRAM head and tail are fall. DRAM 25 may be formed on the same integrated circuit chip as SRAM FIFOS 22 and 30 , or may be separately formed and then connected. The portion of DRAM 25 that is allocated to specific queues such as 20 and 27 may be determined during initialization of the system containing the queues. SRAM FIFOS 22 and 30 afford rapid access to the queues for enqueuing and dequeuing information, while DRAM 25 affords storage for a large number of entries in each queue at minimal cost. SRAM FIFO 22 has individual SRAM storage units, 33 , 35 , 37 and 39 , each containing eight bytes for a total of thirty-two bytes, although the number and capacity of these units may vary in other embodiments. Similarly, SRAM FIFO 30 has SRAM storage units 42 , 44 , 46 and 48 . SRAM units 33 and 35 form a head 50 of FIFO 22 and units 37 and 39 form a tail 52 of that FIFO, while units 42 and 44 form a head 55 of FIFO 30 and units 46 and 48 form a tail 57 of that FIFO. Information for FIFO 22 may be written into head units 33 or 35 , as shown by arrow 60 , and read from tail units 37 or 39 , as shown by arrow 62 . A particular entry, however, may be both written to and read from head units 33 or 35 , or may be both written to and read from tail units 37 or 39 , minimizing data movement and latency. Similarly, information for FIFO 30 is typically written into head units 42 or 44 , as shown by arrow 64 , and read from tail units 46 or 48 , as shown by arrow 66 , but may instead be read from the same head or tail unit to which it was written. While a queue of the present invention may include only one SRAM unit, the availability of plural SRAM units can improve access to SRAM without observable latency from data movement between SRAM and DRAM. Queue 20 may enqueue an entry in DRAM 25 , as shown by arrow 70 , by direct memory access (DMA) units acting under direction of a queue manager, not shown in this figure, instead of being queued in the head or tail of FIFO 22 . Entries stored in DRAM 25 return to SRAM unit 37 , as shown by arrow 73 , extending the length and fall-through time of that FIFO. Diversion of information from SRAM to DRAM is typically reserved for when the SRAM is full, since DRAM is slower and DMA movement causes additional latency. Thus queue 20 may comprise the entries stored by the queue manager in both the FIFO 22 and the DRAM 25 . Likewise, information bound for FIFO 30 can be moved by DMA into DRAM 25 , as shown by arrow 75 . The capacity for queuing in cost-effective albeit slower DRAM 25 is user-definable during initialization, allowing the queues to change in size as desired. Information queued in DRAM 25 can be returned to SRAM unit 46 , as shown by arrow 77 . Movement of information between DRAM and SRAM can be coordinated so that devices utilizing the queue experience SRAM speed although the bulk of queued information may be stored in DRAM. The queue system of the present invention may vary in size and may be used with various devices. Such a queue system may be particularly advantageous for devices that benefit from rapid processing of large amounts of data with plural processors. A preferred embodiment described in detail below and in Verilog code in the microfiche appendix includes a queue manager, SRAM and DRAM controllers and a number of queues that may be used with a network communication device. FIG. 2 depicts the enqueuing and dequeuing of entries in queue 20 for a device 10 such as a processor. When device 10 wants to store data in a queue, information regarding that data is sent to a queue manager 12 , which manages entries in multiple queues such as queue 20 . Queue manager 12 includes a queue controller 14 and DMA units Q 2 D 16 and D 2 Q 18 , which may be part of a number of DMA units acting under the direction of queue controller 14 . DMA units Q 2 D 16 and D 2 Q 18 may be specialized circuitry or dedicated sequencers that transfer data from SRAM to DRAM and vice-versa without using the device 10 . The queue controller 14 enters the data from device 10 in the head 50 of queue 20 , which is composed of SRAM. Should the information be needed again shortly by device 10 , the queue controller can read the entry from head 50 and send it back to device 10 . Otherwise, in order to provide room for another entry in head 50 , DMA unit Q 2 D 16 moves the entry from the SRAM head 50 to DRAM body 25 . Entries are dequeued to device 10 from queue 20 in a similar fashion, with device 10 requesting controller 14 for the next entry from queue 20 , and receiving that entry from tail 52 via controller 14 . DMA unit D 2 Q 18 , operating as a slave to controller 14 , moves entries sequentially from body 25 to SRAM tail 52 , so that entries are immediately available for dequeuing to device 10 . FIG. 3 focuses on a queuing system integrated within a network communication device 160 for a host 170 having a memory 202 and a CPU 205 . The device 160 is coupled to a network 164 via a media access controller 166 and a conventional physical layer interface unit (PHY), not shown, and coupled to the host 170 via a PCI bus 168 . The device 160 maybe provided on the host 170 motherboard or as an add-on network interface card for the host. Although a single network connection is shown in this figure for brevity, the device 160 may offer full-duplex communication for several network connections, partly due to the speed and flexibility of the queuing system. Processing of communications received from and transmitted to the network 164 is primarily handled by receive sequencer 212 and transmit sequencer 215 , respectively. A queue array 200 , which may include thirty-two queues in this embodiment, contains both DRAM 203 and SRAM 206 , where the amount of DRAM 203 earmarked for the queue system can vary in size. The DRAM 203 and SRAM 206 are used for other functions besides the queue array 200 , and may be formed as part of the device or may be separately formed and attached to the device. The device 160 includes a communications microprocessor 208 that interacts with the CPU 205 and host memory 202 across PCI bus 168 via a bus interface unit 210 . A queue manager 220 helps to manage the queue array 200 , via DRAM controller 211 and SRAM controller 214 . Status for each of the hardware queues of the queue array 200 is conveniently maintained by and accessed from a set 80 of four registers, as shown in FIG. 4, in which a specific bit in each register corresponds to a specific queue. The registers are labeled Q-Out_Ready 82 , Q-In_Ready 84 , Q-Empty 86 and Q-Full 88 , and for the thirty-two queue embodiment the registers each have thirty-two bits. If a particular bit is set in the Q-Out_Ready register 82 , the queue corresponding to that bit contains information that is ready to be read, while the setting of the same bit in the Q-In_Ready register 84 means that the queue is ready to be written. Similarly, a positive setting of a specific bit in the Q-Empty register 86 means that the queue corresponding to that bit is empty, while a positive setting of a particular bit in the Q-Full register 88 means that the queue corresponding to that bit is full. Q-Out_Ready 82 contains bits zero 90 through thirty-one 99 in the thirty-two queue embodiment, including bits twenty-seven 95 , twenty-eight 96 , twenty-nine 97 and thirty 98 . Q-In_Ready 84 contains bits zero 100 through thirty-one 109 , including bits twenty-seven 105 , twenty-eight 106 , twenty-nine 107 and thirty 108 . Q-Empty 86 contains bits zero 110 through thirty-one 119 , including bits twenty-seven 115 , twenty-eight 116 , twenty-nine 117 and thirty 118 , and Q-full 88 contains bits zero 120 through thirty-one 129 , including bits twenty-seven 125 , twenty-eight 126 , twenty-nine 127 and thirty 128 . Operation of the queue manager 220 , which manages movement of queue entries between SRAM and the microprocessor, the transmit and receive sequencers, and also between SRAM and DRAM, is shown in more detail in FIG. 5 . Requests, which utilize the queues, include Processor Request 222 , Transmit Sequencer Request 224 , and Receive Sequencer Request 226 . Other requests for the queues are DRAM to SRAM Request (D 2 Q Seq Req) 228 and SRAM to DRAM Request (Q 2 D Seq Req) 230 , which operate on behalf of the queue manager in moving data back and forth between the DRAM and the SRAM head or tail of the queues. Determining which of these various requests will get to use the queue manager in the next cycle is handled by priority logic Arbiter 235 . To enable high frequency operation the queue manager is pipelined, with Register-A 238 and Register-B 240 providing temporary storage, while Status Registers Q_Out_Ready 265 , Q_In_Ready 270 , Q_Empty 275 , and Q_Full 280 maintain status until the next update. The queue manager reserves even cycles for SRAM to DRAM, DRAM to SRAM, receive and transmit sequencer requests and odd cycles for processor requests. Dual ported QRAM 245 stores variables regarding each of the queues, the variables for each queue including a Head Write Pointer, Head Read Pointer, Tail Write Pointer and Tail Read Pointer corresponding to the queue's SRAM condition, and a Body Write Pointer, a Body Read Pointer and a Queue Size Variable corresponding to the queue's DRAM condition and the queue's size. After Arbiter 235 has selected the next operation to be performed, the variables of QRAM 245 are fetched and modified according to the selected operation by a QALU 248 , and an SRAM Read Request 250 or an SRAM Write Request 255 may be generated. The four queue manager registers Q_Out_Ready 265 , Q_In_Ready 270 , Q_Empty 275 , and Q_Full 280 are updated to reflect the new status of the queue that was accessed. The status is also fed to Arbiter 235 to signal that the operation previously requested has been fulfilled, inhibiting duplication of requests. Also updated are SRAM Addresses 283 , Body Write Request 285 and Body Read Requests 288 which are used by DMA CONTROLLER 214 while moving data between SRAM head and DRAM body as well as SRAM tail and DRAM body. If the requested operation was a write to a queue, data as shown by Q Write Data 264 , are selected by multiplexor 266 , and pipelined to SRAM Write Data register 260 . The SRAM controller services the read and write requests by reading the tail or writing the head of the accessed queue and returning an acknowledge. In this manner the various queues can be utilized and their status updated. The array of queues 200 contained within the communication device 160 may include thirty-two queues, for example. At the beginning of operation the device memory is divided into a number of large (2 kilobyte) and small (256 byte) buffers, and pointers denoting the addresses of those buffers are created. These pointers are placed in a large free buffer queue and a small free buffer queue, respectively. Over time, as various operations are executed, these free buffer queues offer a list of addresses for buffers that are available to the communication device 160 or other devices. Due to the potential number of free buffer addresses, these free buffer queues commonly include appreciable DRAM 203 in order to provide sufficient room for listing the buffers available to any device in need of a usable buffer. Note that the queue entries need not be pointers but may, for example, comprise thirty-two bits of control information that is used for communicating with or controlling a device. Another example of a variable capacity queue that may contain a significant amount of DRAM 203 is a trace element queue, which can be used to trace various events that have occurred and provide a history of those events, which may for instance be useful for debugging. FIG. 6 shows a queue system 300 that may be provided on a card that can plug into a computer or similar device. The queue system contains an array of queues that may include both SRAM 303 and DRAM 305 . The queue system may be formed as a single ASIC chip 308 , with the exception of DRAM 305 . The DRAM 305 may be provided on the card as shown or may exist as part of the computer or other device and be connected to the card by a bus. The system 300 may connect to a microprocessor 310 via a microprocessor bus 313 , with a microprocessor bus interface unit 316 translating signals between the microprocessor bus and a queue manager 320 . The queue manager 320 controls DMA units 323 and an SRAM controller 325 that can also control the DMA units 323 . SRAM controller 325 and DMA units 323 can also interact with a DRAM controller 330 , manages and maintains information in DRAM 305 . While the above-described embodiments illustrate several implementations for the queue system of the present invention, it will be apparent to those of ordinary skill in the art that the present invention may be implemented in a number of other ways encompassed by the scope of the following claims. Examples of such implementations include employment for network routers and switches, controllers of peripheral storage devices such as disk drives, controllers for audio or video devices such as monitors or printers, network appliance controllers and multiprocessor computers.
A device for queuing information combines the speed of SRAM with the low cost and low power consumption of DRAM, affording substantial expansion of high-speed data storage in queues without corresponding increases in costs. The queues have a variable size, and provide fast, flexible and efficient data storage via an SRAM interface and a DRAM body. The queues may hold pointers to buffer addresses or other data that allow manipulation of information in the buffers via manipulation of the queues. Particular utility for this mechanism exists in situations for which high-speed access to queues is beneficial, flexible queue size is advantageous, and/or the smaller size and lower cost of DRAM compared to SRAM is of value.
Briefly summarize the invention's components and working principles as described in the document.
[ "MICROFICHE APPENDIX A Microfiche Appendix comprising one sheet, totaling twenty-seven frames is included herewith.", "COPYRIGHT NOTICE A portion of the disclosure of this patent document contains material that is subject to copyright protection.", "The copyright owner has no objection to the reproduction of the patent document or the patent disclosure in exactly the form it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.", "TECHNICAL FIELD The present invention relates to memory circuits for microprocessors.", "BACKGROUND OF THE INVENTION The operation of processors frequently involves temporary storage of information for later manipulation.", "As is well known, data may be stored for random access, or may be stored for access in an ordered fashion such as in a stack or queue.", "A queue stores data entries in sequential fashion, so that the oldest entry in the queue is retrieved first.", "The entry and removal of data in queues may be handled by a central processing unit (CPU) processing software instructions.", "Such a queue system can be a bottleneck in the efficient operation of the processor.", "For example, a first item of information obtained from one process may need to be queued to wait for the processing of another item of information, so that both items may then be manipulated together by the processor.", "The queuing and dequeuing of the first item of information may require additional work of the processor, slowing the eventual processing of both items of information further.", "More complicated situations involving multiple operands and operations cause the queuing and dequeuing complications to multiply, requiring various locks that absorb further processing power and time.", "The size and complexity of a microprocessor can lead to correspondingly large and complex arrangements for storing queues.", "The allocation of memory space for these queues is also challenging, as the queues can vary in length depending upon the type of operations being processed.", "For example, a queuing scheme for a communication system is described by Delp et al.", "in U.S. Pat. No. 5,629,933, in which a number of data packets are stored in first-in, first out (FIFO) order in queues that are segregated by session identity.", "Depending upon activity of a particular session, the number of entries in such queues could be very large or zero.", "In U.S. Pat. No. 5,097,442, Ward et al.", "teach programming a variable number into a register to store that number of data words in a FIFO memory array, up to the limited size of that array.", "To distribute memory for queuing different connections, U.S. Pat. No. 5,812,775 to Van Seters et al.", "teaches a device for a router having a number of network connections that dedicates specific buffers to each network connection as well as providing a pool of buffers for servicing any network connection.", "A number of static random access memory (SRAM) queues are maintained for tracking buffer usage and allocating buffers for storage.", "While SRAM provides relatively quick access compared to dynamic random access memory (DRAM), SRAM memory cells are much larger than DRAM, making SRAM relatively expensive in terms of chip real estate.", "SUMMARY OF THE INVENTION The present invention provides a mechanism for queuing information that is fast, flexible and efficient.", "The mechanism combines the speed of SRAM with the low cost and low power consumption of DRAM, to enable significant expansion of high-speed data storage in queues without corresponding increases in costs.", "The queues may be manipulated by hardware or software, and may provide processing events for an event-driven processor.", "While the queuing mechanism of the present invention can be employed in many systems in place of conventional queues, particular utility is found where high speed access to queues is beneficial, as well for situations in which flexible queue size may be an advantage, and/or for cases where the smaller size and lower cost of DRAM compared to SRAM is of value.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram of a plurality of queues of the present invention.", "FIG. 2 is a diagram of the enqueuing and dequeuing of entries in a queue of FIG. 1 .", "FIG. 3 is a diagram of a network computer implementation of the queue system of the present invention.", "FIG. 4 is a diagram of a plurality of status registers for the queues of FIG. 3 .", "FIG. 5 is a diagram of a queue manager that manages movement of queue entries between various queues in the queue system of FIG. 3 .", "FIG. 6 is a diagram of a queue system that may be provided on a card that plugs into a computer or other device.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a plurality of hardware queues of the present invention, which may contain other such hardware queues as well.", "A first queue 20 is formed of a combination of SRAM 22 and DRAM 25 storage units.", "A second queue 27 is similarly formed as a combination of SRAM 30 and DRAM 25 storage units.", "The queues 20 and 27 each have an SRAM head and tail which can be used as an SRAM FIFO, and the ability to queue information in a DRAM body as well, allowing expansion and individual configuration of each queue.", "Connection between SRAM FIFOS 22 and 30 and DRAM 25 allows those queues 20 and 27 to handle situations in which the SRAM head and tail are fall.", "DRAM 25 may be formed on the same integrated circuit chip as SRAM FIFOS 22 and 30 , or may be separately formed and then connected.", "The portion of DRAM 25 that is allocated to specific queues such as 20 and 27 may be determined during initialization of the system containing the queues.", "SRAM FIFOS 22 and 30 afford rapid access to the queues for enqueuing and dequeuing information, while DRAM 25 affords storage for a large number of entries in each queue at minimal cost.", "SRAM FIFO 22 has individual SRAM storage units, 33 , 35 , 37 and 39 , each containing eight bytes for a total of thirty-two bytes, although the number and capacity of these units may vary in other embodiments.", "Similarly, SRAM FIFO 30 has SRAM storage units 42 , 44 , 46 and 48 .", "SRAM units 33 and 35 form a head 50 of FIFO 22 and units 37 and 39 form a tail 52 of that FIFO, while units 42 and 44 form a head 55 of FIFO 30 and units 46 and 48 form a tail 57 of that FIFO.", "Information for FIFO 22 may be written into head units 33 or 35 , as shown by arrow 60 , and read from tail units 37 or 39 , as shown by arrow 62 .", "A particular entry, however, may be both written to and read from head units 33 or 35 , or may be both written to and read from tail units 37 or 39 , minimizing data movement and latency.", "Similarly, information for FIFO 30 is typically written into head units 42 or 44 , as shown by arrow 64 , and read from tail units 46 or 48 , as shown by arrow 66 , but may instead be read from the same head or tail unit to which it was written.", "While a queue of the present invention may include only one SRAM unit, the availability of plural SRAM units can improve access to SRAM without observable latency from data movement between SRAM and DRAM.", "Queue 20 may enqueue an entry in DRAM 25 , as shown by arrow 70 , by direct memory access (DMA) units acting under direction of a queue manager, not shown in this figure, instead of being queued in the head or tail of FIFO 22 .", "Entries stored in DRAM 25 return to SRAM unit 37 , as shown by arrow 73 , extending the length and fall-through time of that FIFO.", "Diversion of information from SRAM to DRAM is typically reserved for when the SRAM is full, since DRAM is slower and DMA movement causes additional latency.", "Thus queue 20 may comprise the entries stored by the queue manager in both the FIFO 22 and the DRAM 25 .", "Likewise, information bound for FIFO 30 can be moved by DMA into DRAM 25 , as shown by arrow 75 .", "The capacity for queuing in cost-effective albeit slower DRAM 25 is user-definable during initialization, allowing the queues to change in size as desired.", "Information queued in DRAM 25 can be returned to SRAM unit 46 , as shown by arrow 77 .", "Movement of information between DRAM and SRAM can be coordinated so that devices utilizing the queue experience SRAM speed although the bulk of queued information may be stored in DRAM.", "The queue system of the present invention may vary in size and may be used with various devices.", "Such a queue system may be particularly advantageous for devices that benefit from rapid processing of large amounts of data with plural processors.", "A preferred embodiment described in detail below and in Verilog code in the microfiche appendix includes a queue manager, SRAM and DRAM controllers and a number of queues that may be used with a network communication device.", "FIG. 2 depicts the enqueuing and dequeuing of entries in queue 20 for a device 10 such as a processor.", "When device 10 wants to store data in a queue, information regarding that data is sent to a queue manager 12 , which manages entries in multiple queues such as queue 20 .", "Queue manager 12 includes a queue controller 14 and DMA units Q 2 D 16 and D 2 Q 18 , which may be part of a number of DMA units acting under the direction of queue controller 14 .", "DMA units Q 2 D 16 and D 2 Q 18 may be specialized circuitry or dedicated sequencers that transfer data from SRAM to DRAM and vice-versa without using the device 10 .", "The queue controller 14 enters the data from device 10 in the head 50 of queue 20 , which is composed of SRAM.", "Should the information be needed again shortly by device 10 , the queue controller can read the entry from head 50 and send it back to device 10 .", "Otherwise, in order to provide room for another entry in head 50 , DMA unit Q 2 D 16 moves the entry from the SRAM head 50 to DRAM body 25 .", "Entries are dequeued to device 10 from queue 20 in a similar fashion, with device 10 requesting controller 14 for the next entry from queue 20 , and receiving that entry from tail 52 via controller 14 .", "DMA unit D 2 Q 18 , operating as a slave to controller 14 , moves entries sequentially from body 25 to SRAM tail 52 , so that entries are immediately available for dequeuing to device 10 .", "FIG. 3 focuses on a queuing system integrated within a network communication device 160 for a host 170 having a memory 202 and a CPU 205 .", "The device 160 is coupled to a network 164 via a media access controller 166 and a conventional physical layer interface unit (PHY), not shown, and coupled to the host 170 via a PCI bus 168 .", "The device 160 maybe provided on the host 170 motherboard or as an add-on network interface card for the host.", "Although a single network connection is shown in this figure for brevity, the device 160 may offer full-duplex communication for several network connections, partly due to the speed and flexibility of the queuing system.", "Processing of communications received from and transmitted to the network 164 is primarily handled by receive sequencer 212 and transmit sequencer 215 , respectively.", "A queue array 200 , which may include thirty-two queues in this embodiment, contains both DRAM 203 and SRAM 206 , where the amount of DRAM 203 earmarked for the queue system can vary in size.", "The DRAM 203 and SRAM 206 are used for other functions besides the queue array 200 , and may be formed as part of the device or may be separately formed and attached to the device.", "The device 160 includes a communications microprocessor 208 that interacts with the CPU 205 and host memory 202 across PCI bus 168 via a bus interface unit 210 .", "A queue manager 220 helps to manage the queue array 200 , via DRAM controller 211 and SRAM controller 214 .", "Status for each of the hardware queues of the queue array 200 is conveniently maintained by and accessed from a set 80 of four registers, as shown in FIG. 4, in which a specific bit in each register corresponds to a specific queue.", "The registers are labeled Q-Out_Ready 82 , Q-In_Ready 84 , Q-Empty 86 and Q-Full 88 , and for the thirty-two queue embodiment the registers each have thirty-two bits.", "If a particular bit is set in the Q-Out_Ready register 82 , the queue corresponding to that bit contains information that is ready to be read, while the setting of the same bit in the Q-In_Ready register 84 means that the queue is ready to be written.", "Similarly, a positive setting of a specific bit in the Q-Empty register 86 means that the queue corresponding to that bit is empty, while a positive setting of a particular bit in the Q-Full register 88 means that the queue corresponding to that bit is full.", "Q-Out_Ready 82 contains bits zero 90 through thirty-one 99 in the thirty-two queue embodiment, including bits twenty-seven 95 , twenty-eight 96 , twenty-nine 97 and thirty 98 .", "Q-In_Ready 84 contains bits zero 100 through thirty-one 109 , including bits twenty-seven 105 , twenty-eight 106 , twenty-nine 107 and thirty 108 .", "Q-Empty 86 contains bits zero 110 through thirty-one 119 , including bits twenty-seven 115 , twenty-eight 116 , twenty-nine 117 and thirty 118 , and Q-full 88 contains bits zero 120 through thirty-one 129 , including bits twenty-seven 125 , twenty-eight 126 , twenty-nine 127 and thirty 128 .", "Operation of the queue manager 220 , which manages movement of queue entries between SRAM and the microprocessor, the transmit and receive sequencers, and also between SRAM and DRAM, is shown in more detail in FIG. 5 .", "Requests, which utilize the queues, include Processor Request 222 , Transmit Sequencer Request 224 , and Receive Sequencer Request 226 .", "Other requests for the queues are DRAM to SRAM Request (D 2 Q Seq Req) 228 and SRAM to DRAM Request (Q 2 D Seq Req) 230 , which operate on behalf of the queue manager in moving data back and forth between the DRAM and the SRAM head or tail of the queues.", "Determining which of these various requests will get to use the queue manager in the next cycle is handled by priority logic Arbiter 235 .", "To enable high frequency operation the queue manager is pipelined, with Register-A 238 and Register-B 240 providing temporary storage, while Status Registers Q_Out_Ready 265 , Q_In_Ready 270 , Q_Empty 275 , and Q_Full 280 maintain status until the next update.", "The queue manager reserves even cycles for SRAM to DRAM, DRAM to SRAM, receive and transmit sequencer requests and odd cycles for processor requests.", "Dual ported QRAM 245 stores variables regarding each of the queues, the variables for each queue including a Head Write Pointer, Head Read Pointer, Tail Write Pointer and Tail Read Pointer corresponding to the queue's SRAM condition, and a Body Write Pointer, a Body Read Pointer and a Queue Size Variable corresponding to the queue's DRAM condition and the queue's size.", "After Arbiter 235 has selected the next operation to be performed, the variables of QRAM 245 are fetched and modified according to the selected operation by a QALU 248 , and an SRAM Read Request 250 or an SRAM Write Request 255 may be generated.", "The four queue manager registers Q_Out_Ready 265 , Q_In_Ready 270 , Q_Empty 275 , and Q_Full 280 are updated to reflect the new status of the queue that was accessed.", "The status is also fed to Arbiter 235 to signal that the operation previously requested has been fulfilled, inhibiting duplication of requests.", "Also updated are SRAM Addresses 283 , Body Write Request 285 and Body Read Requests 288 which are used by DMA CONTROLLER 214 while moving data between SRAM head and DRAM body as well as SRAM tail and DRAM body.", "If the requested operation was a write to a queue, data as shown by Q Write Data 264 , are selected by multiplexor 266 , and pipelined to SRAM Write Data register 260 .", "The SRAM controller services the read and write requests by reading the tail or writing the head of the accessed queue and returning an acknowledge.", "In this manner the various queues can be utilized and their status updated.", "The array of queues 200 contained within the communication device 160 may include thirty-two queues, for example.", "At the beginning of operation the device memory is divided into a number of large (2 kilobyte) and small (256 byte) buffers, and pointers denoting the addresses of those buffers are created.", "These pointers are placed in a large free buffer queue and a small free buffer queue, respectively.", "Over time, as various operations are executed, these free buffer queues offer a list of addresses for buffers that are available to the communication device 160 or other devices.", "Due to the potential number of free buffer addresses, these free buffer queues commonly include appreciable DRAM 203 in order to provide sufficient room for listing the buffers available to any device in need of a usable buffer.", "Note that the queue entries need not be pointers but may, for example, comprise thirty-two bits of control information that is used for communicating with or controlling a device.", "Another example of a variable capacity queue that may contain a significant amount of DRAM 203 is a trace element queue, which can be used to trace various events that have occurred and provide a history of those events, which may for instance be useful for debugging.", "FIG. 6 shows a queue system 300 that may be provided on a card that can plug into a computer or similar device.", "The queue system contains an array of queues that may include both SRAM 303 and DRAM 305 .", "The queue system may be formed as a single ASIC chip 308 , with the exception of DRAM 305 .", "The DRAM 305 may be provided on the card as shown or may exist as part of the computer or other device and be connected to the card by a bus.", "The system 300 may connect to a microprocessor 310 via a microprocessor bus 313 , with a microprocessor bus interface unit 316 translating signals between the microprocessor bus and a queue manager 320 .", "The queue manager 320 controls DMA units 323 and an SRAM controller 325 that can also control the DMA units 323 .", "SRAM controller 325 and DMA units 323 can also interact with a DRAM controller 330 , manages and maintains information in DRAM 305 .", "While the above-described embodiments illustrate several implementations for the queue system of the present invention, it will be apparent to those of ordinary skill in the art that the present invention may be implemented in a number of other ways encompassed by the scope of the following claims.", "Examples of such implementations include employment for network routers and switches, controllers of peripheral storage devices such as disk drives, controllers for audio or video devices such as monitors or printers, network appliance controllers and multiprocessor computers." ]
CROSS-REFERENCE TO RELATED APPLICATIONS The present application claims priority from German Patent Application No. DE 10 2007 033 279.5, filed Jul. 17, 2007, the contents of which are herein incorporated by reference in its entirety. The present invention relates to a system for object-oriented data management of securities trends. BACKGROUND OF THE INVENTION Successful trading of listed securities depends on being able to recognize and monitor those parameters which decisively affect the value of a security from among a preponderance of the most disparate information. Yet particularly those who are new to the stock markets often face a world which is incomprehensible to them, one which seems to consist of innumerable new terms and unfamiliar conventions. Grasping the at-times, complex mechanisms of the market and the actions which can determine a security's performance, requires seemingly detailed specialized knowledge and is often too challenging for those new to the markets. Right from the very start, these neophytes have to make important, i.e., high-risk decisions which have a direct impact on the monetary stakes. The informed and rapid selection and interpretation of information can therefore be of crucial importance to success in this financial world. Yet the existing systems often impede a neophyte's access to this financial segment, unless the novice is wholly prepared to research the specialized terminology and procedural rules in depth beforehand. The plurality and diversity of communication media available today, now virtually regardless of location or time, affords a good starting point hereto. Traditional information channels such as television, radio and print media, but above all the so-called new media of the internet and its diverse and interactive information offerings via websites, email, chat rooms and online blogs furnish current information virtually around the clock such that this media is ideally suited to being used for market-relevant business applications. The advantage of worldwide access to virtually all information is pitted against the serious disadvantage of those new to the stock market not only having to cull through a preponderance of information, but that comprehending the stock market language and the symbolism with which this information is coded as the cited information channels invariably use cannot be presupposed, especially in the case of one new to the market. An artificial barrier to access is thus initially raised, one which the neophyte can only break through by devoting a great deal of time and concentration to the subject. This is compounded by the fact that the information available on the interaction of rules and effects when trading listed securities is of a structure which is anything but motivating or self-evident to the market layperson. Thus, the stock exchange novice usually sees stock exchange information represented exclusively by numbers and diagrams along with the corresponding technical terms, their complex relationship only discernable at first glance to the market expert. Accordingly, which information could thereby be relevant to the market layperson—often a high-risk decision—the market neophyte has to date had to ferret out alone and yet still bear the consequences which, particularly in the stock market, can have far-reaching impact. Learning the basic principles of trading securities in this way often follows the trial-and-error principle. The diverse information offered is therefore not of real help to the market layperson in this phase of charting such still unknown territory. SUMMARY OF THE INVENTION The task which the present invention therefore addressees is that of specifying a system which makes market-relevant information accessible in a way which is intuitive and quickly grasped by the interested market layperson and which promotes a risk-free and motivated learning of the market's ground rules and an understanding of their complex mechanisms within the stock exchange. The task is solved by a system with which electronic data, which is transmitted from a host computer to a client computer, is converted into a target format which differs from the format in which the data was received at the host computer. In particular, the system includes the following components: 1) a module to receive and store data on a host computer at the request of a client computer in a computer network; a module to convert the data received on the host computer by means of a conversion rule into an object-oriented data format which can be processed by a client computer; a module to transmit the converted data to a client computer upon request of the client computer, its display unit reproducing the transmitted data as graphical objects; and 2) a module for the interactive processing of the transmitted data on the client computer by the user. In the electronic data that was transmitted to the client computer, the representation methodology for the electronic data is understood to be that which displays this transmitted data on the display unit of the client computer. That means the electronic data, which usually consist of numbers, and which can be attributed a specific information content, is displayed in another more comprehensible way on the client computer; thus, being presented in another format, the target format, which nevertheless still represents the same information content originally attributed to the electronic data. The technical interface denotes a system-controlled application which filters the inbound electronic data from an external computer network and forwards the same for processing to the appropriate intrasystem module of the inventive system. Termed the object-oriented data format, is the inventive representation methodology for the electronic data which presents this electronic data in a context-dependent representative form consisting of graphical objects, symbols or icons, which can also be differentiated by their assigned color. The intrasystem approach to generating a correspondent graphical symbol with equivalent information content from the electronic data is termed a conversion rule as implemented in the system according to the invention. The electronic data converted into graphical symbols can be processed interactively by the user; i.e., the user has the opportunity to directly influence the appearance, position and/or type of graphical objects depicted on the display unit of the client computer by means of specific default mouse and/or key combinations and can additionally call up further information attributed to the graphical objects. An essential point of the invention relates to stock market-relevant data, thus, data which is made available directly from one or more selected world-wide virtual stock exchanges, is displayed exclusively with graphical objects. What this thereby achieves, is that even complex issues and context, as can arise when trading in securities, are brought home to the market layperson in an understandable and motivating manner so as to enable the layperson to intuitively interpret this information so essential to him or her quickly and correctly, solely due to the representative form of the graphical objects. The market layperson, drawing on the interactive use of the system, thus, receives—in consideration of his or her previous knowledge—a cautious introduction to the stock exchange world, gradually gaining the expertise to recognize the complex interactions inherent to securities trading and being able to coherently interpret market-relevant information and use it to make the appropriate decisions. It is thus, for example, provided for a single graphical object—assuming the task of a multi-functional information carrier—to be assigned a plurality of information items. This has the advantage that a preponderance of information which to date could only be considered as individual items, can be depicted simultaneously for faster comprehension by the market neophyte. If this information has an interdependency as cause-effect variables, this then additionally promotes an intuitive understanding of the complex associations between the graphically-depicted parameters which can have a bearing on a security's market value. The information content of a graphical object is specified by the representative form assigned to it. There are additionally three degrees of freedom to the visual parameters of form, color and positioning of a graphical object within a defined reference area in order to combine a preponderance of information in a meaningful manner using only one graphical object. This has the advantage that the market layperson can grasp and attribute the continually changing information content at a quick glance and nevertheless, still maintain the overview, since the individually depicted graphical objects are clearly visually differentiated from one another. The automatic customization of the specific representative form of a graphical object moreover allows a more targeted responsiveness to the sentiments of the addressed target group. The system, furthermore, provides for the specific representative form of the graphical objects as information carriers to adjust dynamically to the security's performance during the active trading hours of the stock exchange. The user can thus, monitor the market performance of the selected security in real time. The individual market trend stages at defined times, thus, the respective specific representative forms of the selected information carrier at a defined point in time, are thereby frozen and depicted such that the up-to-the-minute market trend for the security can be gleaned at a glance. It is provided in one embodiment, for the system to depict the sales and performance of a security being monitored in real time with only one graphical object. The market layperson, thus, receives an immediate status report on his or her selected security's trend for any point in time. In another embodiment, the graphical objects encompass the information carrier being able to assume the function of interactive buttons. The graphical objects can thereby trigger information-processing events such as, e.g., the display of context-related information in the form of news, comments, text balloons, etc., the same being automatically controlled by the system. It is however, also provided for the market layperson to be able to trigger such events directly with his or her mouse in order to thereby expand his/her own interaction radius. For a clear, well-designed arrangement of the graphical objects, it is advantageously provided for their dynamic positioning within a defined area of a so-called market performance field. This thereby, always provides the market layperson with a precise overview of the current status of the market/sales trend for his or her selected security. The market performance field is additionally advantageously subdivided such that the current market trend for the selected security can be deduced from the relative position of the graphical objects at a defined point in time so that just one field is sufficient in order to depict market-relevant information, thereby considerably enhancing clarity. The market performance field advantageously allows for integrating interactive online services within a defined area in which the up-to-the-minute security performance is positioned dynamically in the market performance field. This online service enables the market layperson to call up additional information and/or exchange information with other networked subscribers, for example, with chat/blog functions. Yet he or she can simultaneously keep an eye on the current status of the monitored security's development so as to be able to react at any time to changes without needing to switch back and forth between different views. In another embodiment, the market performance field provides for using its free spaces for the placing of interactive informational advertising content such as, e.g., online advertisements. By furnishing additional information on varied topics, products and services, companies would thereby be able to run target group-oriented advertising. The advertisements, run online in combination with images, text or interactive elements which respond to user interaction, can thereby be motion-controlled across the area of the market performance field. The duration of the ad shown—i.e., its presence online or the time during which the informational advertising content is visible for the logged-in user—can thereby be configured by the system accordingly. The duration of an online presence for the depicted informational advertising content can also be made contingent on a leasing fee the advertising client pays in advance to the respective provider. The advertising client thereby purchases online time in order to be allowed to advertise his products in the market performance field. This form of advertisement is not limited exclusively to the market performance field of the application, however, and can also be implemented in other display panels and menus of the application according to the invention based on client requests and specifications. The time and manner of representation regarding the online informational advertising content can moreover be advantageously adapted to the operating or open hours of the available worldwide stock market exchanges selected by the user. However, it would be just as conceivable to use the free spaces of the market performance field for running informational advertising content after a stock exchange closes, when the stock performance display for the user's selected virtual stock exchanges is halted in the market performance field. The logged-in user then has the opportunity to either consider the informational advertising content shown or have another look at the stock performance for a selected interval of time, for example the past day from his preferred virtual stock exchange. Advertisers are thus, given an online platform which allows them to accordingly run target group-specific advertising content at selected periods of time. The form and format of the presented informational advertising content is naturally just as configurable by the system during the booked online time. In another embodiment, furnishing the informational advertising content additionally provides for the content of the presented informational advertising content to be adapted to the interests of the logged-in user, his/her user profile respectively, provided that the user has made this information publicly available and agrees to being shown personalized informational advertising content. This form of personalized advertising yields a win-win situation for both sides: namely, the advertiser only offers a potential customer that informational advertising content on its products online which could be of interest to said customer; and the customer, on the other hand, is spared advertising content which would not be of interest to him or her or not match his/her user profile. The system moreover provides for the transmitted stock exchange data to be automatically transformed into an interactive security map, the market selection account, according to defined categories and rules. Selected market quotations along with their trend histories are listed therein for the preselected country according to industry and company affiliation. Based on this listing, the market layperson can easily put together his or her individual securities portfolio with which he or she can then trade. Each category in the market selection account is additionally allocated it own assigned color code which is uniformly used in order to simplify the user's assigning of a listed security to a corresponding category. In another embodiment, the user-defined selection of securities in the market selection account, which the market layperson is interested in trading, are summarized in an interactive securities account—the test account. In so doing, the dynamically-variable market prices for the selected securities are likewise depicted in the manner described above by characteristic, likewise dynamically-variable representative forms of graphical objects so that the market layperson receives an immediate overview of the current market status of the selected securities in his or her test account, with which he or she can trade during trading hours. The test account always displays the current balance resulting from the activities of the market layperson to same in a practical manner so that such neophytes are kept informed of the effects of their transactions at all times. The overall result of the transactions effected by the market layperson with his/her selected securities is then displayed in a further summarizing interactive securities account, the so-called profit account. This view also works exclusively with graphical objects as information carriers so that the market layperson can immediately grasp the effects of his/her transactions. A further embodiment of the described system provides for the functional configuration of the different views within the application such as market performance field, test account and profit account, to adjust automatically to the foreknowledge of the market layperson. By so doing, market laypersons who have no previous knowledge or experience whatsoever in dealing with stock exchange information are not confronted with information and functionalities which are initially incomprehensible to them. Hence, at a first level, only those basic functions which are necessary for a minimum understanding of dealing with securities are made available to the user. Once, however, the market layperson becomes more familiar with the fundamental terms and rules of stock exchange transactions, he or she can then interactively select a second level of further functionalities and additional market-relevant information. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments and drawings will be used in the following to specify the invention in greater detail. FIG. 1 is a representation of one embodiment of the inventive structure of the system and its connection to external data processing systems; FIG. 1 a is a two-dimensional representation of the home page of the website for selecting the respective country; FIG. 1 b is a two-dimensional representation of the market selection account with a detailed depiction of the catalogued distribution of the selectable market quotations; FIG. 2 is a two-dimensional representation of the market performance field containing graphical objects in accordance with the invention; FIG. 3 is a two-dimensional representation of the market performance field with a dynamically-positionable placeholder for the integration of interactive online services; FIG. 4 is a two-dimensional representation of an interactive securities account (test account) with a detailed depiction of the daily result realized; FIG. 5 is a two-dimensional representation of an interactive profit account; FIG. 6 a is a two-dimensional representation of an interactive profit account including detailed rate data on buy-date X; FIG. 6 b is a two-dimensional representation of an interactive profit account including detailed rate data on buy-date Y; FIG. 6 c is a two-dimensional representation of the daily result realized on buy-date Y. FIG. 7 is a representation of the market performance field with integrated informational advertising content DESCRIPTION OF THE INVENTION FIG. 1 shows the system 1 . 1 according to one embodiment of the invention with the modules 1 . 2 , 1 . 3 , 1 . 4 and 1 . 5 and its connections to external and internal interfaces. Electronic data 1 . 7 is hereby supplied from an external computer network 1 . 9 , which consists of computers 1 . 9 a , and delivered to system 1 . 1 via a technical interface 1 . 6 . The system 1 . 1 processes the delivered data 1 . 7 pursuant an intrasystem conversion rule and transmits the transformed electronic data 1 . 8 , which the system 1 . 1 converted into a new target format, to the user's client computer 1 . 10 , the display unit 1 . 11 of which displays the transformed electronic data in the form of graphical objects. The client computer 1 . 10 itself can in turn be a component of a further computer network 1 . 12 which can be comprised of further interconnected client computers 1 . 12 a. FIG. 1 a shows the home page of the application's website. On this home page, the user first selects that country 02 , along with its listed securities and indices, in which he or she wants to trade. The user is moreover shown the respectively current market trend of the country-specific stock exchange indices in the “Today's Market” column 04 . In the market selection account 1 of FIG. 1 b , the user can select his or her favourite securities for speculation from a global pool of available stock exchanges listing the most important securities and stock exchange indices for the respective country. Available for user selection are thereby the categories of Collective Securities 2 , which indicates the exchange indices of the participating countries, Industry Class 3 such as, e.g., banks and the automotive industry, and the Company Value 4 associated with the industry classes. The fields of each category are thereby respectively coded by means of a significant category-allocated color so that the user quickly grasps the meaning of the respective fields. The significant color coding also remains as such in the various different views. There is furthermore the possibility in the market selection account 1 to trace the daily and historical trends for the respectively displayed securities. This is represented by a corresponding graphical character 10 , e.g. a “+” or “−” sign for rising/falling market trends, or a numerical value in the columns entitled Current Date 5 , Month 6 for the historical monthly market trend, Year 7 for the historical yearly market trend and Dividend 8 indicating a dividend payout. The graphical symbols to be entered in the respective columns thereby correspond to specific quoted numerical values for the daily, monthly and yearly market trends as furnished by an interface and transformed for display in the market selection account. As is additionally evident from FIG. 1 , each industry represented has its own industry-related icon 9 . The selection of the user's securities is thereafter transferred to the user's personal test and profit account. The market selection account furthermore, enables the companies which are listed in the Industry Class 3 category to advertise nationally or internationally on their respective sales/performance element page. The sales/performance element page is thereby a special page from which the user can receive a listing of the data associated with a company in terms of its sales and market value rates. The market performance field 20 of FIG. 2 chronicles and displays the up-to-the-minute market trend of a selected security. The respectively selected security is displayed in the form of a graphical object 22 which migrates across the field during the market's trading hours. The field contains a virtual coordinate system which plots invisible horizontal and vertical reference lines by means of which corresponding information content can be allocated and read out based on the position of a graphical object. In the horizontally-extending trend of the virtual coordinate system, the field is divided into time zones, e.g., hour segments 23 , in order to simulate the length of a full trading day so that the selected security's performance can be tracked at any given point in time. The corresponding sunrise 24 and sunset 25 icons indicate the market's opening and closing to the user. The position of a graphical object in the vertically-extending trend attributes a specific respective positive or negative result to the graphical object. The representative form of the graphical object 22 enables performance and revenue information to be displayed using just one single graphical object. This is achieved by the appropriate coding to the color and design of a graphical object, its representative form changing in real time depending upon the current stock performance. Each specific representative form of a graphical object is assigned the corresponding market figures which the stock exchange delivers to an interface. These market figures as furnished are transformed in the market performance field pursuant the described method so that the position and representative form of a graphical object is controlled solely by the listed security with which the graphical object is coupled. Graphical objects can correspondingly likewise be used to symbolically depict occurring events such as, e.g., stock price plunges, etc. A graphical object, in addition to its flexibly linkable information content, is also an interactive element which can display system-triggered or user-triggered information. One representative form, for example, thus, provides for a user being able to call up additional information, e.g. by way of text balloons, etc., by clicking on a graphical object. The market performance field furthermore, consists of fixed and variable elements. A fixed element can for example be a horizontally-extending center line 26 which divides the field into an upper and a lower half. By so doing, the two sections of the divided field can each be allocated additional visual information content which can be manifested for example by means of a dynamically changed background color. Another representative form, for example, is provided by a graphical object 27 positioned above the center line being assigned a positive performance/revenue value by the appropriate color value and representative form; when in contrast the graphical object 22 is in the field section below the center line, the graphical object displays a different corresponding representative form in order to symbolize its negative performance/revenue value. The variable elements in the market performance field 20 are comprised of graphical objects, colors, diagrams, icons and other similar visual tools. In the market performance field 22 of FIG. 3 , which shows the integration of online services, an unused area can be used to make interactive online services and/or current information available to the user, for example individual transaction status on traded securities. In one representative form, for example, interactive applications 29 with chat and/or blog functionalities are conceivable in order to make communication possible between networked users. The unused area can likewise be used as an advertising vehicle for companies. The size and position of this unused area intended for such interactive services is thereby dynamically configurable and shifts to the right on a virtual horizontal line as the trading day progresses so that each graphical object 22 displayed always remains visible to the user. Test account 30 , one representative form of which is depicted in FIG. 4 as an example, displays a specific number of current daily values 32 for the Collective Securities, Industry Class and individual Company Values which the user can, e.g., drag-and-drop from his/her market selection account 1 into his/her test account 30 . In so doing, the user buys a specific number of securities at a fixed price on the buy-date, the performance of which can then be monitored in the market performance field 20 . The test account depicts the market trend for the selected securities on the buy-date by means of a first daily test account 30 a and on the day after the buy-date by means of a second daily test account 30 b. Upon the lapsing of a specific period of time, e.g., one week, the user can moreover exchange the selected securities for others. The test account 30 itself is linked to a technical interface which transmits the continuously varying values on the securities being monitored to the test account 30 so that the user can track the market trend of the listed securities 32 in real time during trading hours. In the present embodiment of the test account of FIG. 4 , the positive and negative results ensuing from the user's trading activities with the individual securities 41 are additionally displayed in bar-graph form. The length of a bar stands in direct relation to the current price of a security. If the reference mark, i.e., the value of a security on day X, is for example at a value of 100 Euro and the bar extends above that, this is then a sign of the security's increase in value. Analogously, when the bar falls below the reference mark, this is then a sign that the security has lost value compared to an earlier point in time, for example the day before. The color of a bar changes as a function of whether the security assigned to it has gained or lost value. After a specific stock exchange closes, apparent from the respective date 46 in FIG. 5 , the user will be displayed a corresponding positive or negative balance 42 in his/her profit account 40 in FIG. 5 . The balance 42 results from the addition and subtraction of the individual values from the represented daily test accounts 30 a and 30 b from FIG. 4 . The profit account 40 uses graphical objects to show the daily positive/negative results 42 realized by the user on the day after purchasing the corresponding securities. The profit account in FIG. 5 is automatically updated in real time. Each internet subscriber can set up one or a plurality of profit accounts. Each profit account is supplied a virtual sum of money in the respective country's currency on buy-date X, which the user can use for speculating with his or her selected securities. In a further use of the profit account, the user can for example send in his/her realized daily results within the confines of a contest. The profit account with the highest daily balance surplus is paid the amount exceeding the buy-date sum. By the same token, the poorest profit account result is also awarded. In the further FIG. 6 representation of a profit account, the FIG. 5 representation has been rotated 90°. In this representation as well, the length of the bars constitutes a proportional measure of a security's current value. The corresponding values 50 of the respective securities are additionally indicated in numerical values here. In FIG. 6 a , the respective shares 53 of the individual securities are listed and a reference value 50 is assigned to represent the value of a security at the indicated time point X. FIG. 6 b indicates the state of the profit account relative another, usually later, time point Y from that in FIG. 6 a . The changed market values 57 for the individual securities are indicated here by the change in bar length and the corresponding numerical values 57 . FIG. 6 c then calculates and displays the positive or negative result 60 for the security transactions at time point Y from FIG. 6 b which results from the difference between the results for the individual securities 57 from FIG. 6 b and the given amount 62 of the total investment from FIG. 6 c. Informational advertising content is integrated into the market performance field of FIG. 7 . This informational advertising content, which can span the entire background area of the market performance field, can be time-controlled; i.e., the online advertisements of an advertising client can be contingent, among other factors, upon the online time which the advertising client has booked by paying the corresponding fee. One variant of the embodiment additionally provides for the type of representation to the displayed informational advertising content to change in line with the daily, monthly or yearly trend to the market quotation. FIG. 7 shows an embodiment, for example, in which the background image for the informational advertising content to be displayed is continuously replaced by an area of lesser transparency over the progressive course of the day for a selected virtual stock exchange market. For example, when the selected market time is 12:00 p.m., 50% of the background image is already concealed. After the market closes, however, it would be 100%; i.e., the informational advertising content would be completely masked at this point in time and no longer visible to the logged-in user. In this way, although not limited to this embodiment, presented informational advertising content can be successively shown and hidden at a specific rate, thus, indicating the correlation between booked online time and displayed advertising content. It should be emphasized that the above-described embodiments of the invention are merely possible examples of implementations set forth for a clear understanding of the principles of the invention. Variations and modifications may be made to the above-described embodiments of the invention without departing from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of the invention and protected by the following claims.
A system for processing electronic data which is transmitted from a host computer to a client computer is provided. The system converts the electronic data into a target format that differs from the format in which the data was received at the host computer. With the system, stock market-relevant information is to be made accessible, intuitive, and quickly grasped by market laypersons and promotes risk-free and motivating learning of the market's ground rules and an understanding of their complex mechanisms within the stock exchange. The system includes modules to receive and store data on a host computer, to convert the data received at the host computer by a conversion rule into an object-oriented data format, to transmit the converted data to a client computer, its display unit reproducing the transmitted data as graphical objects; and to interactively process the transmitted data on the client computer.
Briefly describe the main idea outlined in the provided context.
[ "CROSS-REFERENCE TO RELATED APPLICATIONS The present application claims priority from German Patent Application No. DE 10 2007 033 279.5, filed Jul. 17, 2007, the contents of which are herein incorporated by reference in its entirety.", "The present invention relates to a system for object-oriented data management of securities trends.", "BACKGROUND OF THE INVENTION Successful trading of listed securities depends on being able to recognize and monitor those parameters which decisively affect the value of a security from among a preponderance of the most disparate information.", "Yet particularly those who are new to the stock markets often face a world which is incomprehensible to them, one which seems to consist of innumerable new terms and unfamiliar conventions.", "Grasping the at-times, complex mechanisms of the market and the actions which can determine a security's performance, requires seemingly detailed specialized knowledge and is often too challenging for those new to the markets.", "Right from the very start, these neophytes have to make important, i.e., high-risk decisions which have a direct impact on the monetary stakes.", "The informed and rapid selection and interpretation of information can therefore be of crucial importance to success in this financial world.", "Yet the existing systems often impede a neophyte's access to this financial segment, unless the novice is wholly prepared to research the specialized terminology and procedural rules in depth beforehand.", "The plurality and diversity of communication media available today, now virtually regardless of location or time, affords a good starting point hereto.", "Traditional information channels such as television, radio and print media, but above all the so-called new media of the internet and its diverse and interactive information offerings via websites, email, chat rooms and online blogs furnish current information virtually around the clock such that this media is ideally suited to being used for market-relevant business applications.", "The advantage of worldwide access to virtually all information is pitted against the serious disadvantage of those new to the stock market not only having to cull through a preponderance of information, but that comprehending the stock market language and the symbolism with which this information is coded as the cited information channels invariably use cannot be presupposed, especially in the case of one new to the market.", "An artificial barrier to access is thus initially raised, one which the neophyte can only break through by devoting a great deal of time and concentration to the subject.", "This is compounded by the fact that the information available on the interaction of rules and effects when trading listed securities is of a structure which is anything but motivating or self-evident to the market layperson.", "Thus, the stock exchange novice usually sees stock exchange information represented exclusively by numbers and diagrams along with the corresponding technical terms, their complex relationship only discernable at first glance to the market expert.", "Accordingly, which information could thereby be relevant to the market layperson—often a high-risk decision—the market neophyte has to date had to ferret out alone and yet still bear the consequences which, particularly in the stock market, can have far-reaching impact.", "Learning the basic principles of trading securities in this way often follows the trial-and-error principle.", "The diverse information offered is therefore not of real help to the market layperson in this phase of charting such still unknown territory.", "SUMMARY OF THE INVENTION The task which the present invention therefore addressees is that of specifying a system which makes market-relevant information accessible in a way which is intuitive and quickly grasped by the interested market layperson and which promotes a risk-free and motivated learning of the market's ground rules and an understanding of their complex mechanisms within the stock exchange.", "The task is solved by a system with which electronic data, which is transmitted from a host computer to a client computer, is converted into a target format which differs from the format in which the data was received at the host computer.", "In particular, the system includes the following components: 1) a module to receive and store data on a host computer at the request of a client computer in a computer network;", "a module to convert the data received on the host computer by means of a conversion rule into an object-oriented data format which can be processed by a client computer;", "a module to transmit the converted data to a client computer upon request of the client computer, its display unit reproducing the transmitted data as graphical objects;", "and 2) a module for the interactive processing of the transmitted data on the client computer by the user.", "In the electronic data that was transmitted to the client computer, the representation methodology for the electronic data is understood to be that which displays this transmitted data on the display unit of the client computer.", "That means the electronic data, which usually consist of numbers, and which can be attributed a specific information content, is displayed in another more comprehensible way on the client computer;", "thus, being presented in another format, the target format, which nevertheless still represents the same information content originally attributed to the electronic data.", "The technical interface denotes a system-controlled application which filters the inbound electronic data from an external computer network and forwards the same for processing to the appropriate intrasystem module of the inventive system.", "Termed the object-oriented data format, is the inventive representation methodology for the electronic data which presents this electronic data in a context-dependent representative form consisting of graphical objects, symbols or icons, which can also be differentiated by their assigned color.", "The intrasystem approach to generating a correspondent graphical symbol with equivalent information content from the electronic data is termed a conversion rule as implemented in the system according to the invention.", "The electronic data converted into graphical symbols can be processed interactively by the user;", "i.e., the user has the opportunity to directly influence the appearance, position and/or type of graphical objects depicted on the display unit of the client computer by means of specific default mouse and/or key combinations and can additionally call up further information attributed to the graphical objects.", "An essential point of the invention relates to stock market-relevant data, thus, data which is made available directly from one or more selected world-wide virtual stock exchanges, is displayed exclusively with graphical objects.", "What this thereby achieves, is that even complex issues and context, as can arise when trading in securities, are brought home to the market layperson in an understandable and motivating manner so as to enable the layperson to intuitively interpret this information so essential to him or her quickly and correctly, solely due to the representative form of the graphical objects.", "The market layperson, drawing on the interactive use of the system, thus, receives—in consideration of his or her previous knowledge—a cautious introduction to the stock exchange world, gradually gaining the expertise to recognize the complex interactions inherent to securities trading and being able to coherently interpret market-relevant information and use it to make the appropriate decisions.", "It is thus, for example, provided for a single graphical object—assuming the task of a multi-functional information carrier—to be assigned a plurality of information items.", "This has the advantage that a preponderance of information which to date could only be considered as individual items, can be depicted simultaneously for faster comprehension by the market neophyte.", "If this information has an interdependency as cause-effect variables, this then additionally promotes an intuitive understanding of the complex associations between the graphically-depicted parameters which can have a bearing on a security's market value.", "The information content of a graphical object is specified by the representative form assigned to it.", "There are additionally three degrees of freedom to the visual parameters of form, color and positioning of a graphical object within a defined reference area in order to combine a preponderance of information in a meaningful manner using only one graphical object.", "This has the advantage that the market layperson can grasp and attribute the continually changing information content at a quick glance and nevertheless, still maintain the overview, since the individually depicted graphical objects are clearly visually differentiated from one another.", "The automatic customization of the specific representative form of a graphical object moreover allows a more targeted responsiveness to the sentiments of the addressed target group.", "The system, furthermore, provides for the specific representative form of the graphical objects as information carriers to adjust dynamically to the security's performance during the active trading hours of the stock exchange.", "The user can thus, monitor the market performance of the selected security in real time.", "The individual market trend stages at defined times, thus, the respective specific representative forms of the selected information carrier at a defined point in time, are thereby frozen and depicted such that the up-to-the-minute market trend for the security can be gleaned at a glance.", "It is provided in one embodiment, for the system to depict the sales and performance of a security being monitored in real time with only one graphical object.", "The market layperson, thus, receives an immediate status report on his or her selected security's trend for any point in time.", "In another embodiment, the graphical objects encompass the information carrier being able to assume the function of interactive buttons.", "The graphical objects can thereby trigger information-processing events such as, e.g., the display of context-related information in the form of news, comments, text balloons, etc.", ", the same being automatically controlled by the system.", "It is however, also provided for the market layperson to be able to trigger such events directly with his or her mouse in order to thereby expand his/her own interaction radius.", "For a clear, well-designed arrangement of the graphical objects, it is advantageously provided for their dynamic positioning within a defined area of a so-called market performance field.", "This thereby, always provides the market layperson with a precise overview of the current status of the market/sales trend for his or her selected security.", "The market performance field is additionally advantageously subdivided such that the current market trend for the selected security can be deduced from the relative position of the graphical objects at a defined point in time so that just one field is sufficient in order to depict market-relevant information, thereby considerably enhancing clarity.", "The market performance field advantageously allows for integrating interactive online services within a defined area in which the up-to-the-minute security performance is positioned dynamically in the market performance field.", "This online service enables the market layperson to call up additional information and/or exchange information with other networked subscribers, for example, with chat/blog functions.", "Yet he or she can simultaneously keep an eye on the current status of the monitored security's development so as to be able to react at any time to changes without needing to switch back and forth between different views.", "In another embodiment, the market performance field provides for using its free spaces for the placing of interactive informational advertising content such as, e.g., online advertisements.", "By furnishing additional information on varied topics, products and services, companies would thereby be able to run target group-oriented advertising.", "The advertisements, run online in combination with images, text or interactive elements which respond to user interaction, can thereby be motion-controlled across the area of the market performance field.", "The duration of the ad shown—i.e., its presence online or the time during which the informational advertising content is visible for the logged-in user—can thereby be configured by the system accordingly.", "The duration of an online presence for the depicted informational advertising content can also be made contingent on a leasing fee the advertising client pays in advance to the respective provider.", "The advertising client thereby purchases online time in order to be allowed to advertise his products in the market performance field.", "This form of advertisement is not limited exclusively to the market performance field of the application, however, and can also be implemented in other display panels and menus of the application according to the invention based on client requests and specifications.", "The time and manner of representation regarding the online informational advertising content can moreover be advantageously adapted to the operating or open hours of the available worldwide stock market exchanges selected by the user.", "However, it would be just as conceivable to use the free spaces of the market performance field for running informational advertising content after a stock exchange closes, when the stock performance display for the user's selected virtual stock exchanges is halted in the market performance field.", "The logged-in user then has the opportunity to either consider the informational advertising content shown or have another look at the stock performance for a selected interval of time, for example the past day from his preferred virtual stock exchange.", "Advertisers are thus, given an online platform which allows them to accordingly run target group-specific advertising content at selected periods of time.", "The form and format of the presented informational advertising content is naturally just as configurable by the system during the booked online time.", "In another embodiment, furnishing the informational advertising content additionally provides for the content of the presented informational advertising content to be adapted to the interests of the logged-in user, his/her user profile respectively, provided that the user has made this information publicly available and agrees to being shown personalized informational advertising content.", "This form of personalized advertising yields a win-win situation for both sides: namely, the advertiser only offers a potential customer that informational advertising content on its products online which could be of interest to said customer;", "and the customer, on the other hand, is spared advertising content which would not be of interest to him or her or not match his/her user profile.", "The system moreover provides for the transmitted stock exchange data to be automatically transformed into an interactive security map, the market selection account, according to defined categories and rules.", "Selected market quotations along with their trend histories are listed therein for the preselected country according to industry and company affiliation.", "Based on this listing, the market layperson can easily put together his or her individual securities portfolio with which he or she can then trade.", "Each category in the market selection account is additionally allocated it own assigned color code which is uniformly used in order to simplify the user's assigning of a listed security to a corresponding category.", "In another embodiment, the user-defined selection of securities in the market selection account, which the market layperson is interested in trading, are summarized in an interactive securities account—the test account.", "In so doing, the dynamically-variable market prices for the selected securities are likewise depicted in the manner described above by characteristic, likewise dynamically-variable representative forms of graphical objects so that the market layperson receives an immediate overview of the current market status of the selected securities in his or her test account, with which he or she can trade during trading hours.", "The test account always displays the current balance resulting from the activities of the market layperson to same in a practical manner so that such neophytes are kept informed of the effects of their transactions at all times.", "The overall result of the transactions effected by the market layperson with his/her selected securities is then displayed in a further summarizing interactive securities account, the so-called profit account.", "This view also works exclusively with graphical objects as information carriers so that the market layperson can immediately grasp the effects of his/her transactions.", "A further embodiment of the described system provides for the functional configuration of the different views within the application such as market performance field, test account and profit account, to adjust automatically to the foreknowledge of the market layperson.", "By so doing, market laypersons who have no previous knowledge or experience whatsoever in dealing with stock exchange information are not confronted with information and functionalities which are initially incomprehensible to them.", "Hence, at a first level, only those basic functions which are necessary for a minimum understanding of dealing with securities are made available to the user.", "Once, however, the market layperson becomes more familiar with the fundamental terms and rules of stock exchange transactions, he or she can then interactively select a second level of further functionalities and additional market-relevant information.", "BRIEF DESCRIPTION OF THE DRAWINGS Embodiments and drawings will be used in the following to specify the invention in greater detail.", "FIG. 1 is a representation of one embodiment of the inventive structure of the system and its connection to external data processing systems;", "FIG. 1 a is a two-dimensional representation of the home page of the website for selecting the respective country;", "FIG. 1 b is a two-dimensional representation of the market selection account with a detailed depiction of the catalogued distribution of the selectable market quotations;", "FIG. 2 is a two-dimensional representation of the market performance field containing graphical objects in accordance with the invention;", "FIG. 3 is a two-dimensional representation of the market performance field with a dynamically-positionable placeholder for the integration of interactive online services;", "FIG. 4 is a two-dimensional representation of an interactive securities account (test account) with a detailed depiction of the daily result realized;", "FIG. 5 is a two-dimensional representation of an interactive profit account;", "FIG. 6 a is a two-dimensional representation of an interactive profit account including detailed rate data on buy-date X;", "FIG. 6 b is a two-dimensional representation of an interactive profit account including detailed rate data on buy-date Y;", "FIG. 6 c is a two-dimensional representation of the daily result realized on buy-date Y. FIG. 7 is a representation of the market performance field with integrated informational advertising content DESCRIPTION OF THE INVENTION FIG. 1 shows the system 1 .", "1 according to one embodiment of the invention with the modules 1 .", "2 , 1 .", "3 , 1 .", "4 and 1 .", "5 and its connections to external and internal interfaces.", "Electronic data 1 .", "7 is hereby supplied from an external computer network 1 .", "9 , which consists of computers 1 .", "9 a , and delivered to system 1 .", "1 via a technical interface 1 .", "6 .", "The system 1 .", "1 processes the delivered data 1 .", "7 pursuant an intrasystem conversion rule and transmits the transformed electronic data 1 .", "8 , which the system 1 .", "1 converted into a new target format, to the user's client computer 1 .", "10 , the display unit 1 .", "11 of which displays the transformed electronic data in the form of graphical objects.", "The client computer 1 .", "10 itself can in turn be a component of a further computer network 1 .", "12 which can be comprised of further interconnected client computers 1 .", "12 a. FIG. 1 a shows the home page of the application's website.", "On this home page, the user first selects that country 02 , along with its listed securities and indices, in which he or she wants to trade.", "The user is moreover shown the respectively current market trend of the country-specific stock exchange indices in the “Today's Market”", "column 04 .", "In the market selection account 1 of FIG. 1 b , the user can select his or her favourite securities for speculation from a global pool of available stock exchanges listing the most important securities and stock exchange indices for the respective country.", "Available for user selection are thereby the categories of Collective Securities 2 , which indicates the exchange indices of the participating countries, Industry Class 3 such as, e.g., banks and the automotive industry, and the Company Value 4 associated with the industry classes.", "The fields of each category are thereby respectively coded by means of a significant category-allocated color so that the user quickly grasps the meaning of the respective fields.", "The significant color coding also remains as such in the various different views.", "There is furthermore the possibility in the market selection account 1 to trace the daily and historical trends for the respectively displayed securities.", "This is represented by a corresponding graphical character 10 , e.g. a “+”", "or “−”", "sign for rising/falling market trends, or a numerical value in the columns entitled Current Date 5 , Month 6 for the historical monthly market trend, Year 7 for the historical yearly market trend and Dividend 8 indicating a dividend payout.", "The graphical symbols to be entered in the respective columns thereby correspond to specific quoted numerical values for the daily, monthly and yearly market trends as furnished by an interface and transformed for display in the market selection account.", "As is additionally evident from FIG. 1 , each industry represented has its own industry-related icon 9 .", "The selection of the user's securities is thereafter transferred to the user's personal test and profit account.", "The market selection account furthermore, enables the companies which are listed in the Industry Class 3 category to advertise nationally or internationally on their respective sales/performance element page.", "The sales/performance element page is thereby a special page from which the user can receive a listing of the data associated with a company in terms of its sales and market value rates.", "The market performance field 20 of FIG. 2 chronicles and displays the up-to-the-minute market trend of a selected security.", "The respectively selected security is displayed in the form of a graphical object 22 which migrates across the field during the market's trading hours.", "The field contains a virtual coordinate system which plots invisible horizontal and vertical reference lines by means of which corresponding information content can be allocated and read out based on the position of a graphical object.", "In the horizontally-extending trend of the virtual coordinate system, the field is divided into time zones, e.g., hour segments 23 , in order to simulate the length of a full trading day so that the selected security's performance can be tracked at any given point in time.", "The corresponding sunrise 24 and sunset 25 icons indicate the market's opening and closing to the user.", "The position of a graphical object in the vertically-extending trend attributes a specific respective positive or negative result to the graphical object.", "The representative form of the graphical object 22 enables performance and revenue information to be displayed using just one single graphical object.", "This is achieved by the appropriate coding to the color and design of a graphical object, its representative form changing in real time depending upon the current stock performance.", "Each specific representative form of a graphical object is assigned the corresponding market figures which the stock exchange delivers to an interface.", "These market figures as furnished are transformed in the market performance field pursuant the described method so that the position and representative form of a graphical object is controlled solely by the listed security with which the graphical object is coupled.", "Graphical objects can correspondingly likewise be used to symbolically depict occurring events such as, e.g., stock price plunges, etc.", "A graphical object, in addition to its flexibly linkable information content, is also an interactive element which can display system-triggered or user-triggered information.", "One representative form, for example, thus, provides for a user being able to call up additional information, e.g. by way of text balloons, etc.", ", by clicking on a graphical object.", "The market performance field furthermore, consists of fixed and variable elements.", "A fixed element can for example be a horizontally-extending center line 26 which divides the field into an upper and a lower half.", "By so doing, the two sections of the divided field can each be allocated additional visual information content which can be manifested for example by means of a dynamically changed background color.", "Another representative form, for example, is provided by a graphical object 27 positioned above the center line being assigned a positive performance/revenue value by the appropriate color value and representative form;", "when in contrast the graphical object 22 is in the field section below the center line, the graphical object displays a different corresponding representative form in order to symbolize its negative performance/revenue value.", "The variable elements in the market performance field 20 are comprised of graphical objects, colors, diagrams, icons and other similar visual tools.", "In the market performance field 22 of FIG. 3 , which shows the integration of online services, an unused area can be used to make interactive online services and/or current information available to the user, for example individual transaction status on traded securities.", "In one representative form, for example, interactive applications 29 with chat and/or blog functionalities are conceivable in order to make communication possible between networked users.", "The unused area can likewise be used as an advertising vehicle for companies.", "The size and position of this unused area intended for such interactive services is thereby dynamically configurable and shifts to the right on a virtual horizontal line as the trading day progresses so that each graphical object 22 displayed always remains visible to the user.", "Test account 30 , one representative form of which is depicted in FIG. 4 as an example, displays a specific number of current daily values 32 for the Collective Securities, Industry Class and individual Company Values which the user can, e.g., drag-and-drop from his/her market selection account 1 into his/her test account 30 .", "In so doing, the user buys a specific number of securities at a fixed price on the buy-date, the performance of which can then be monitored in the market performance field 20 .", "The test account depicts the market trend for the selected securities on the buy-date by means of a first daily test account 30 a and on the day after the buy-date by means of a second daily test account 30 b. Upon the lapsing of a specific period of time, e.g., one week, the user can moreover exchange the selected securities for others.", "The test account 30 itself is linked to a technical interface which transmits the continuously varying values on the securities being monitored to the test account 30 so that the user can track the market trend of the listed securities 32 in real time during trading hours.", "In the present embodiment of the test account of FIG. 4 , the positive and negative results ensuing from the user's trading activities with the individual securities 41 are additionally displayed in bar-graph form.", "The length of a bar stands in direct relation to the current price of a security.", "If the reference mark, i.e., the value of a security on day X, is for example at a value of 100 Euro and the bar extends above that, this is then a sign of the security's increase in value.", "Analogously, when the bar falls below the reference mark, this is then a sign that the security has lost value compared to an earlier point in time, for example the day before.", "The color of a bar changes as a function of whether the security assigned to it has gained or lost value.", "After a specific stock exchange closes, apparent from the respective date 46 in FIG. 5 , the user will be displayed a corresponding positive or negative balance 42 in his/her profit account 40 in FIG. 5 .", "The balance 42 results from the addition and subtraction of the individual values from the represented daily test accounts 30 a and 30 b from FIG. 4 .", "The profit account 40 uses graphical objects to show the daily positive/negative results 42 realized by the user on the day after purchasing the corresponding securities.", "The profit account in FIG. 5 is automatically updated in real time.", "Each internet subscriber can set up one or a plurality of profit accounts.", "Each profit account is supplied a virtual sum of money in the respective country's currency on buy-date X, which the user can use for speculating with his or her selected securities.", "In a further use of the profit account, the user can for example send in his/her realized daily results within the confines of a contest.", "The profit account with the highest daily balance surplus is paid the amount exceeding the buy-date sum.", "By the same token, the poorest profit account result is also awarded.", "In the further FIG. 6 representation of a profit account, the FIG. 5 representation has been rotated 90°.", "In this representation as well, the length of the bars constitutes a proportional measure of a security's current value.", "The corresponding values 50 of the respective securities are additionally indicated in numerical values here.", "In FIG. 6 a , the respective shares 53 of the individual securities are listed and a reference value 50 is assigned to represent the value of a security at the indicated time point X. FIG. 6 b indicates the state of the profit account relative another, usually later, time point Y from that in FIG. 6 a .", "The changed market values 57 for the individual securities are indicated here by the change in bar length and the corresponding numerical values 57 .", "FIG. 6 c then calculates and displays the positive or negative result 60 for the security transactions at time point Y from FIG. 6 b which results from the difference between the results for the individual securities 57 from FIG. 6 b and the given amount 62 of the total investment from FIG. 6 c. Informational advertising content is integrated into the market performance field of FIG. 7 .", "This informational advertising content, which can span the entire background area of the market performance field, can be time-controlled;", "i.e., the online advertisements of an advertising client can be contingent, among other factors, upon the online time which the advertising client has booked by paying the corresponding fee.", "One variant of the embodiment additionally provides for the type of representation to the displayed informational advertising content to change in line with the daily, monthly or yearly trend to the market quotation.", "FIG. 7 shows an embodiment, for example, in which the background image for the informational advertising content to be displayed is continuously replaced by an area of lesser transparency over the progressive course of the day for a selected virtual stock exchange market.", "For example, when the selected market time is 12:00 p.m., 50% of the background image is already concealed.", "After the market closes, however, it would be 100%;", "i.e., the informational advertising content would be completely masked at this point in time and no longer visible to the logged-in user.", "In this way, although not limited to this embodiment, presented informational advertising content can be successively shown and hidden at a specific rate, thus, indicating the correlation between booked online time and displayed advertising content.", "It should be emphasized that the above-described embodiments of the invention are merely possible examples of implementations set forth for a clear understanding of the principles of the invention.", "Variations and modifications may be made to the above-described embodiments of the invention without departing from the spirit and principles of the invention.", "All such modifications and variations are intended to be included herein within the scope of the invention and protected by the following claims." ]
STATEMENT OF PRIORITY The present application claims priority to U.S. Provisional Application No. 61/898,362, titled “Process For The Production Of An Enriched Natural Antioxidant Mixture From A Single Source Plant” and filed Oct. 31, 2013. TECHNICAL FIELD The present disclosure relates to the field of therapeutic natural products and a process for producing an enriched extraction of a natural antioxidant mixture rich in cinnamic acids, catechins, amino acids and xanthines from a single source plant material, guayusa, which can be used to prevent a host of inflammatory diseases such as diabetes, cancer, heart disease, Alzheimer's and obesity as well as help treat ailments associated with poor glucose metabolism, endothelial dysfunction, oxidative stress, inflammation and cognitive decline. BACKGROUND Ilex guayusa is an Amazonian tree of the holly genus, native to the Ecuadorian Amazon Rainforest. The plant yields xanthenes such as caffeine. In addition to caffeine, guayusa also contains theobromine, a stimulant commonly found in chocolate and L-theanine, a glutamic acid analog found in green tee that has been shown to reduce physical and mental stress. See Kimura K, Ozeki M, Jeneja L, Ohira H (2007). “L-Theanine reduces psychological and physiological stress responses.” Biol Psychol 74 (1): 39-45. doi: 10.1016/j.biopsycho.2006.06.006 (http://dxdoi.org/10.1016%2Fj.biopsycho.2006.06.006). PMID16930802 (//hwww.ncbi.nlm.nih.gov/pubmed/16930802). Current approaches for the use of the guayusa plant include steeping the leaves and forming a beverage substrate (the “tea”) as previously disclosed in http://www.stashtea.com/info/guayusa.aspx and http://www.runa.org/our-guayusa/. The finished beverage produced from both the tea leaves and the Ready to Drink (“RTD”) beverages is described as a naturally caffeinated herbal infusion produced from the leaves of a holly tree. The finished beverage composition contains antioxidants, catechins, vitamins and amino acids at relatively low levels (Antioxidant and Compounds Analysis of Guayusa tea, “Lab Number: 056939”. Advanced Botanical Consulting & Testing, Inc., 2010) as well as xanthines or caffeine as a natural sources of energy, FIG. 1 . Accordingly, there is a need to find natural remedies for inflammatory diseases and enhance cognitive function through the production of an extract which contains a specific ratio of actives that allow for effective nutritional formulation and dosage in a concentrated way to ensure product efficacy without having to consume large volumes of liquid. In addition, there is a need for an extract or essence of the guayusa tea leaves with an enhanced finished product sensory profile and a shelf life extension. Specifically, a need exists for a masking agent stabilizing oxidative damage to the antioxidant content without bitterness in a finished tea based beverages (IFT 2013, Chicago, Ill. Presented by TEAWOLF). Finally, there is need for a medicinal extract with the specific active ratio which provides for health benefits not yet seen or described by ingestion of the guayusa tea alone. See Antioxidant and Compounds Analysis of Guayusa tea, “ Lab Number: 056939”. Advanced Botanical Consulting & Testing, Inc., 2010. Suggestive of their role in disease prevention, the active compounds in the guayusa plant, once harvested and concentrated to the correct ratio as described within the disclosure, demonstrate and provide enhanced beneficial effects in human health. SUMMARY OF THE INVENTION According to one aspect, the present disclosure relates to a process for extracting antioxidants from a plant, including contacting a plant material from a guayusa plant for a first time with a solvent, thereby obtaining a first slurry, filtering said first slurry, thereby obtaining a first extract, contacting said plant material for a second time with said solvent, thereby obtaining a second slurry, filtering said second slurry, thereby obtaining a second extract, combining said first extract and said second extract, thereby generating an third extract containing at least antioxidants, xanthines, and amino acids, and substantially drying said third extract. In another aspect, the present disclosure relates to an antioxidant mixture prepared by a process comprising the steps of: contacting a plant material from a guayusa plant for a first time with a solvent, thereby obtaining a first slurry, filtering said first slurry, thereby obtaining a first extract, contacting said plant material for a second time with said solvent, thereby obtaining a second slurry, filtering said second slurry, thereby obtaining a second extract, combining said first extract and said second extract, thereby generating an third extract containing at least antioxidants, xanthines, and amino acids, and substantially drying said third extract. BRIEF DESCRIPTION OF THE DRAWINGS The following FIGURE are included to illustrate certain aspects of the present invention, and should not be viewed as an exclusive embodiments. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to one having ordinary skill in the art and the benefit of this disclosure. FIG. 1 is a prior art lab result, Antioxidant and Compounds Analysis of Guayusa tea, “Lab Number: 056939”. Advanced Botanical Consulting & Testing, Inc., 2010. DETAILED DESCRIPTION Definitions The term “filtration” is used to refer to either ultrafiltration or nanofiltration. In general, the “permeate” is the component that passes freely through the filter, while the “retentate” is the component that is retained by the filter. The term “microfiltration” refers to processes that use filtration membranes having larger pore size than both ultrafiltration and nanofiltration. Microfiltration involves subjecting the antioxidant extract or eluate to filtration through a filter having a pore size of less than about 0.50 μM. As used herein, the term “nanofiltration” refers to processes that use filtration membranes having a smaller molecular weight or pore size than those typically used in ultrafiltration processes. Like ultrafiltration, nanofiltration rejects a portion of the extract or eluate components above a certain molecular size while allowing those of a smaller size to pass through. Suitable nanofiltration membranes for use in the process disclosed herein are preferably made from polymers having a nominal molecular weight cut off of from about 700 Da to about 5000 Da (corresponding to pore sizes in the range of from about 17 A to about 40 A). Particularly preferred nanofiltration membranes are made from polymers having a nominal molecular weight cut off of from about 800 Da to about 2000 Da (corresponding to pore sizes in the range of from about 18 A to about 27 A). This pore size, in general, allows unoxidized phenolic compounds to pass through the membrane while retaining larger sized protein like compounds. As used herein, the term “plant material” means species of guayusa ( Ilex guayusa ), preferably the tea leaves. As used herein, the terms “antioxidant-containing eluate” and “antioxidant eluate” are used interchangeably to refer to the desired antioxidant-containing component collected after exposure to the adsorbent as described herein. Such adsorption step may be column adsorption, or any other adsorption means known to those having ordinary skill in the art. As used herein, the term “nutrient-rich extract” means an extract having a nutrient concentration of at least about 5 times, and preferably at least about 15 times, the starting composition based on the High-Performance Liquid Chromatography (“HPLC”) measurement, of the desired compounds (chlorogenic acids, xanthines, amino acids and flavonoids). As used herein, the term “antioxidant containing retentate” means the amino acid-containing components remaining on the upstream side of the filter after ultrafiltration or nanofiltration. Such amino acid-containing retentates are used as the source of polyphenols, flavonoids, xanthines and other water soluble vitamins. As used herein, the terms “amino acid-containing eluate,” “amino acid eluate” and “amino acid rich extract” are used interchangeably to refer to the desired amino acid-containing components collected after exposure to the adsorbent as described herein such as the L-theanine or luecine. Such adsorption step may be column adsorption, or any other adsorption means known to those having ordinary skill in the art. As used herein, the term “ultrafiltration” means a filtration method that uses an open filtration membrane with a pore size capable of allowing through molecules from at least about 10,000 Da to at least about 100,000 Da in molecular weight. Typically, ultrafiltration removes large molecular weight polysaccharides and proteins, but not oxidized phenolics. As used herein, the term “water,” means any of: deionized water, reverse osmosis water, distilled water, process water, ion exchange or mixtures thereof. All amounts, parts, ratios and percentages used herein are by weight unless otherwise specified. Process The first step in one embodiment of the presently disclosed process disclosed herein involves blanching the leaves by contacting the plant material with boiling water, preferably greater than 80° C., for approximately 30 seconds. In some embodiments, this step may also utilize other leaf pretreatment methods such as steam blanching, citric acid blanching or a convention withering step. However, in preferable embodiments, optimum conditions are met with non withered leaves to avoid any un-necessary oxidation of the phytochemicals prior to extraction. The blanched leaves are then contacted with a solvent to obtain an extract comprising the soluble antioxidants (flavonoids and cinnamic acids), xanthines, and amino acids. The plant material used in the present disclosure is guayusa ( Ilex guayusa ), and more preferably the guayusa leaves (other Ilex species with the particular nutrients desired may also be used, i.e. Ilex vomitoria ). The preferred extraction process involves steeping the guayusa leaves in and ethanol:hot water solution. The guayusa leaves are extracted using a 70:30 ethanol:hot water solution from about 70° C. to about 100° C. (from about 158 F. to about 212° F.), preferably from about 75° C. to about 90° C. (from about 167° F. to about 194° F.), and more preferably from about 80° C. to about 85° C. (from about 176° F. to about 185° F.), and a combined tea leaf to solvent ratio of about from 1:10 to about 1:20, i.e. for every 1 kg of guayusa leaves used, about 10 to 20 kg of solvent solution is used. Additionally, the extraction can be completed using a complete water extraction, supercritical extraction or similar however the yields of polyphenols and catechins and other active compounds will change. The guayusa leaves are soaked in the solvent between approximately 60 minutes to approximately 240 minutes, after which the wet leaves are filtered out through one or more layers of cheese cloth, or other similar straining material, and the antioxidant extract is collected. The wet leaves may then be re-extracted numerous additional times (preferably two or three more times) with another volume of hot water or a water solvent mixture and soaked for about 60 minutes to about 120 minutes further. The leaves are again filtered out and the nutrient rich extract collected. The filtered nutrient extracts can then combined and are ready for further processing or the second nutrient rich extract can be further processes itself, then combined with the first for a finished extract with ideal product specifications. Exposing Extract to Absorbent In one embodiment, the nutrient rich extract resulting from the previous step is subsequently exposed to an adsorbent, which separates the desired compounds from other associated substances, such as the pectins and fiber. The result is a nutrient rich containing eluate that is substantially free of the aforementioned associated insoluble compounds and impurities. The preferred method of carrying out this adsorption step is column chromatography. However, any similar method of separation commonly known to those skilled in the art is acceptable. For example, the nutrient rich extract and adsorbent may be combined in a solvent medium and mixed thoroughly or through a multistage supercritical extraction process. As previously mentioned, column chromatography is the preferred method to separate the desired extract from the other components in the nutrient rich extract. To separate via column chromatography, an inert column, preferably one made of glass or plastic, is first packed with an adsorbent or column packing. The adsorbent material may be any of a variety of hydrophobic cationic materials, however, polymeric resins, such as polyamides or polyclar are preferred. The column is then equilibrated with a solvent that is preferably water-soluble and does not form two phases when mixed with water. The solvent utilized in this phase of the process is preferably selected from water, ethanol, propylene glycol, glycerin, weak solutions of acetone, propanols, other like alcohols, and mixtures thereof. More preferably, the solvent comprises a mixture of water and ethanol. Still more preferably, the solvent mixture comprises less than about 80%, preferably less than about 70% ethanol, by weight of the solvent. In an alternate embodiment, the solvent comprises water. Next, the nutrient rich extract is pumped through the column and the components that are not adsorbed, or poorly adsorbed, i.e. amino acids, will be the first class of components to elute with the solvent. As the solvent strength is increased, such as, for example, through the addition of more ethanol, more strongly adsorbed components are released from the adsorbent material in the column and elute with the solvent. This process allows for the separation of the desired materials and the production of an amino acid rich-containing eluate having a composition containing at least approximately 5% total amino acids. Filtration of the Amino Acid-Containing Eluate The amino acid containing eluate is then subjected to a filtration step, to remove additional high molecular weight material, such as polysaccharides, pectins and fiber, and further enrich the nutritional concentration of the eluate. As defined above, this filtration step may be either ultrafiltration or nanofiltration. Each of these filtration processes is set forth below Nanofiltration involves contacting the amino acid eluate with a nanofiltration membrane to provide a filtered nutrient-rich extract. Nanofiltration according to the present disclosure removes the higher molecular weight materials such as polysaccharides, pectins and fibers. It is preferred that the nanofiltration step be carried out while the nutrient eluate is at a temperature of from about 30° C. to about 50° C. (about 86° F. to about 122° F.), preferably from about 35° C. to about 50° C. (about 95° F. to about 122° F.), and more preferably from about 45° C. to about 50° C. (about 113° F. to about 122° F.). Efficient nanofiltration is typically achieved by warming the nutrient eluate after exposure to the adsorbent material and just prior to nanofiltration. The pressure at which nanofiltration is carried out is preferably sufficiently high to provide adequate flow of the nutrient eluate through the membrane to achieve the desired processing. However, the pressure is preferably not so high as to remove substantial amounts of water from the system. According to the present disclosure, nanofiltration is typically carried out under a hydrostatic pressure of from about 100 psi to about 300 psi, preferably from about 180 psi to about 280 psi, applied to the upstream side of the membrane. Suitable nanofiltration membranes for use in the process of the present disclosure are made from polymers having a nominal molecular weight cut off of from about 700 Da to about 5000 Da (corresponding to pore sizes in the range of from about 17 A to about 40 A). Preferred nanofiltration membranes are made from polymers having a nominal molecular weight cut off of from about 800 Da to about 2000 Da (corresponding to pore sizes in the range of from about 18 A to about 27 A). Suitable polymers are those that have less affinity for the desired polyphenol I flavonoid components in the nutrient eluate. Polymers such as cellulose and the like are usually suitable for making these nanofiltration membranes. Typically, the resulting amino acid-rich extract is cooled to a temperature of about 16° C. (about 60° F.) or less. Similar to nanofiltration, ultrafiltration involves contacting the nutrient eluate with an ultrafiltration membrane to provide a filtered nutrient-rich extract. Ultrafiltration uses an open filtration membrane with a pore size capable of allowing through molecules from at least about 10,000 Da to at least about 100,000 Da in molecular weight. When utilizing ultrafiltration, the nutrient eluate can generally be filtered at a temperature of from about 30° C. to about 50° C. (about 86° F. to about 122° F.), preferably from about 35° C. to about 50° C. (about 95° F. to about 122° F.), and more preferably from about 45° C. to about 50° C. (about 113° F. to about 122° F.). Once the nutrient eluate is subjected to one of the aforementioned filtration processes the nutrient composition obtained contains not less than approximately 10% total amino acids. The resulting amino acid-rich extract can now be enriched with the antioxidant polyphenols and xanthines removed during the initial extraction and separation steps by combining the two concentrated extracts, where evaporation and drying can produce a finished extract that contains no less than 30% chlorogenic acids, 10% xanthines and 5% amino acids, or 45 w/w % total nutrients. More specifically, the finished extract contains no less than 40% chlorogenic acids, 15% xanthines and 10% amino acids, or 65 w/w % total nutrients. Using the Nutrient-Rich Extract After subjecting the plant material to one of the foregoing embodiments, the resulting nutrient-rich extract may then be used to lower the glycemic response of a subject in a more effective way than prior guayusa compositional function (see Swanston-Flatt, S K et. Al Glycaemic effects of traditional European plant treatments for diabetes. Studies in normal and streptozotocin diabetic mice. Diabetes Res. 1989 February; 10(2):69-73) and assist in mood enhancement, provide a natural source of energy, decrease the risk of cardiovascular disease, enhance brain function, assist with weight management and lower oxidative stress. The specific composition produced can provide an optimum source of natural energy that contains both an active element for enhanced metabolic function with its caffeine content while also assisting with glucose metabolism and regulation with the high level of chlorogenic acids. This ratio provides an ideal synergistic level of chlorogenic acids and caffeine to achieve effective weight loss benefits, whilst still shunting overactive insulin activity and hypertension typically associated with an increase in caffeine consumption. Further, the specific composition may provide a masking agent to control the astringent, brackish or bitter taste when formulating, add a level of sweetness to the product or allow for increased shelf stability by protecting or stabilizing the finished formulation from oxidation. EXAMPLES Example 1 The following examples are illustrative of embodiments disclosed herein. Parts and percentages are by dry weight unless otherwise indicated. It should be noted that these examples describe a wide range of conditions, which together with the above descriptions, illustrate the present disclosure in a non limiting fashion. About 400 g of commercial quality non withered guayusa tea leaves are extracted with about 1000 L of an ethanol:deionized water solution (70:30), at about 75° C. to about 85° C. (about 167° F. to about 186° F.) for approximately 120 minutes. The resulting slurry is filtered through two layers of muslin cloth and yields about 1200 g of crude tea extract. The residual leaves are re-extracted with deionized water under the foregoing conditions and again filtered through muslin cloth three more times. The tea extracts are combined and subjected to vacuum drying to concentrate the extract and remove additional impurities at about 80° C. until less than 3% moisture. The above semi solid extract is dissolved in ethanol then the top layer decanted. The top layer is then dried in a rotary drum dryer until less than 2% moisture. The final extract contains a profile of chlorogenic acids, catechins and caffeine for use as a nutritional ingredient in food and beverage applications. The final extract phytochemical profile is as seen in Table 1: TABLE 1 Serial No. Phyto-constituent Assay in w/w % Analysis method 1 Total Polyphenols 35 ± 0.5 w/w % Folin-Ciocalteu by spectrophotometric method 2 Total Chlorogenic 32 ± 0.35 w/w % LCMS/MS method acids 3 Caffeine 26 ± 0.25 w/w % LCMS/MS method 4 Theobromine 0.0215 ± 0.005 w/w % LCMS/MS method 5 L-Theanine 0.011 ± 0.003 w/w % LCMS/MS method Example 2 About 200 g of commercial quality guayusa tea leaves are extracted with about 550 L of an ethanol:deionized water solution (70:30), at about 75° C. to about 85° C. (about 167° F. to about 186° F.) for approximately 120 minutes. The resulting slurry is filtered through two layers of muslin cloth and yields about 1200 g of crude tea extract. The residual leaves are re-extracted with deionized water under the foregoing conditions and again filtered through muslin cloth. The tea extracts are combined and subjected to microfiltration via a 0.45 μM pleated filter (1.5 ft.sup.2, acrylic co-polymer on a polypropylene-polyester support). The resulting permeate is then subjected to nanofiltration using a Millipore® 1000 Dalton Molecular Weight Cut Off (MWCO) filter. The resulting permeate is then used to produce a clarified tea extract which contain the chlorogenic acids, xanthines and other phenols. The retentates from these filtrations, which contain the amino acids and glycosides, are combined to yield an amino acid-containing retentate with a volume of about 300 ml and about S0 Bx. This extract has an active concentration of about 600 mg/L. The nutrient rich extract is diluted with deionized water in a 1:1 ratio, and used as feed in the next step. Amberlite XAD 16HP® (Rohm & Haas) is packed in a column (2.5 cm ID.times.75 cm height) to give a column volume of about 350 ml. The column is washed with about 4-5 column volumes of deionized water. The diluted nutrient extract from the foregoing extraction step is pumped into the column until breakthrough occurs (about 100 ml). The column is first eluted with deionized water to remove the non-phenolic materials including amino acids and other polysaccharides. When the eluate gives no precipitate or a clouding reaction with ethanol, the water elution is stopped. This eluate contains about 200 mg/L amino acids and about 10 mg/ml tea polysaccharides. It is then nanofiltered using a 1000 Dalton MWCO membrane to separate the high molecular weight non-phenolic materials from amino acids. The amino acid-rich extract is then added to the clarified polyphenol tea extract and further concentrated under vacuum until dry to remove any residual solvents and impurities. The finished substrate is then solubilized in a distilled solution and dried in a rotary evaporator to produce an extract of less than approximately 3% moisture. The final extract phytochemical profile is as seen in Table 2: TABLE 2 Serial No. Phyto-constituent Assay in w/w % Analysis method 1 Total Polyphenols 47.1 ± 1.5 w/w % Folin-Ciocalteu by spectrophotometric method 2 Total Chlorogenic 41.5 ± 0.35 w/w % LCMS/MS method acids 3 Caffeine 36.8 ± 0.25 w/w % LCMS/MS method 4 Catechins 7.2 ± 0.05 w/w % LCMS/MS method 5 L-Theanine 1.40 ± 0.04 w/w % LCMS/MS method 6 Theobromine 0.266 ± 0.007 w/w % LCMS/MS method Example 3 200 grams of non-withered Guayusa tea leaves are extracted with an Ethanol:water mixture (95:5) at 55° C. to about 65° C. The water to tea leaves ratio is about 15:1. This extraction is continued for about 2 hours, and the resulting nutrient dense extract is filtered using a filtration funnel with a waterman filtering paper. The residual tea leaves are then extracted twice more with an ethanol:water solvent at a ratio of 90:10, and this second and third nutrient extracts 2 and 3 are passed through filtration using whatman filter paper to remove any residual tea powder residue. The three nutrient extracts are combined, and the total active content in them is determined to be about 220 mg/L. The combined extracts are send through a buchi rotary evaporator vacuum pump to concentrate the extract and remove any residual solvents. The semi-solid extract is completely dried using a savant speedvac vacuum system. The final extract provides a nutrient dense substrate containing the optimum combination of antioxidants and caffeine for use as a nutritional component in foods, beverages and supplements. The final extract phytochemical profile is as seen in Table 3: TABLE 3 Serial No. Analysis Amount Method 1 Total Polyphenols 22.3 ± 1.5 w/w % Folin-Ciocalteu by spectrophotometric method 2 Total Chlorogenic 21.1 ± 0.35 w/w % LCMS/MS method acids 3 Caffeine 17.6 ± 0.15 w/w % LCMS/MS method 4 Catechins 1.5 ± 0.05 w/w % LCMS/MS method 5 L-Theanine 0.002 ± 0.04 w/w % LCMS/MS method 6 Theobromine 0.165 ± 0.007 w/w % LCMS/MS method Example 4 Seven female subjects, ages 29-45, were given 300 mg of guayusa extract containing 42% chlorogenic acid, 16% xanthines and 12% amino acids orally for 3 weeks. Subjects were measured at the onset and upon final administration for Nuerotransmitter levels of Serotonin, GABA, Dopamine, Norepinephrine, Epinephrine, Glutamate and Creatinine Results demonstrate an increase in Serotonin and GABA levels by 22% and 26% respectively, and an increase in of Dopamine, Norephipephrine, Epinephrine by 12%, 11% and 15%. Glutamate and Creatinine levels remained unchanged. Example 5 Two sets of six ready-to-drink tea beverages were prepared by steeping conventional green tea leaves in water at a 1:1 ratio for ten minutes, filtering, pasteurizing, then bottling. With one set, prior to bottling, 200 mg of guayusa extract was added that contained 32% chlorogenic acid, 16% xanthines and 5% amino acids and 30% total glycosides. Packaging was carried out in conventional 500 ml RTD glass bottles and sealed with PTFE screw lined caps. The tea beverages were stored for a period of 12 weeks in a temperature controlled light deprived container. One sample from each set was analyzed over the 12 weeks period for total flavonol glycoside concentration and total EGCG concentration. Over the 12 weeks period, the control set containing no guayusa reduced total glycoside concentration by 37% and total EGCG concentration by 40% with most of the degration during the last two weeks of the study, week 10-week 12. Over the same 12 week period the six green tea beverages containing the 200 mg of guayusa extract per 500 ml seen an average decrease in total glycosides of 2% and a total average decrease in EGCG of 8%. In addition sensory scores completed on both sets indicated an increase in overall product taste as sweetness score by 92% of the sensory evaluations. Although the present disclosure has been described with reference to specific embodiments, this description is not meant to be construed in a limited sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the disclosure will become apparent to persons skilled in the art upon the reference to the description of the present disclosure. It is, therefore, contemplated that the appended claims will cover modifications that fall within the scope of the disclosure.
A process for extracting antioxidants from a plant, including contacting a plant material from a guayusa plant for a first time with a solvent, thereby obtaining a first slurry, filtering said first slurry, thereby obtaining a first extract, contacting said plant material for a second time with said solvent, thereby obtaining a second slurry, filtering said second slurry, thereby obtaining a second extract, combining said first extract and said second extract, thereby generating an third extract containing at least antioxidants, xanthines, and amino acids, and substantially drying said third extract.
Briefly summarize the main idea's components and working principles as described in the context.
[ "STATEMENT OF PRIORITY The present application claims priority to U.S. Provisional Application No. 61/898,362, titled “Process For The Production Of An Enriched Natural Antioxidant Mixture From A Single Source Plant”", "and filed Oct. 31, 2013.", "TECHNICAL FIELD The present disclosure relates to the field of therapeutic natural products and a process for producing an enriched extraction of a natural antioxidant mixture rich in cinnamic acids, catechins, amino acids and xanthines from a single source plant material, guayusa, which can be used to prevent a host of inflammatory diseases such as diabetes, cancer, heart disease, Alzheimer's and obesity as well as help treat ailments associated with poor glucose metabolism, endothelial dysfunction, oxidative stress, inflammation and cognitive decline.", "BACKGROUND Ilex guayusa is an Amazonian tree of the holly genus, native to the Ecuadorian Amazon Rainforest.", "The plant yields xanthenes such as caffeine.", "In addition to caffeine, guayusa also contains theobromine, a stimulant commonly found in chocolate and L-theanine, a glutamic acid analog found in green tee that has been shown to reduce physical and mental stress.", "See Kimura K, Ozeki M, Jeneja L, Ohira H (2007).", "“L-Theanine reduces psychological and physiological stress responses.”", "Biol Psychol 74 (1): 39-45.", "doi: 10.1016/j.", "biopsycho[.", "].2006.06.006 (http://dxdoi.org/10.1016%2Fj.", "biopsycho[.", "].2006.06.006).", "PMID16930802 (//hwww.", "ncbi.", "nlm.", "nih.gov/pubmed/16930802).", "Current approaches for the use of the guayusa plant include steeping the leaves and forming a beverage substrate (the “tea”) as previously disclosed in http://www.", "stashtea.com/info/guayusa.", "aspx and http://www.", "runa.org/our-guayusa/.", "The finished beverage produced from both the tea leaves and the Ready to Drink (“RTD”) beverages is described as a naturally caffeinated herbal infusion produced from the leaves of a holly tree.", "The finished beverage composition contains antioxidants, catechins, vitamins and amino acids at relatively low levels (Antioxidant and Compounds Analysis of Guayusa tea, “Lab Number: 056939.”", "Advanced Botanical Consulting &", "Testing, Inc., 2010) as well as xanthines or caffeine as a natural sources of energy, FIG. 1 .", "Accordingly, there is a need to find natural remedies for inflammatory diseases and enhance cognitive function through the production of an extract which contains a specific ratio of actives that allow for effective nutritional formulation and dosage in a concentrated way to ensure product efficacy without having to consume large volumes of liquid.", "In addition, there is a need for an extract or essence of the guayusa tea leaves with an enhanced finished product sensory profile and a shelf life extension.", "Specifically, a need exists for a masking agent stabilizing oxidative damage to the antioxidant content without bitterness in a finished tea based beverages (IFT 2013, Chicago, Ill.", "Presented by TEAWOLF).", "Finally, there is need for a medicinal extract with the specific active ratio which provides for health benefits not yet seen or described by ingestion of the guayusa tea alone.", "See Antioxidant and Compounds Analysis of Guayusa tea, “ Lab Number: 056939.”", "Advanced Botanical Consulting &", "Testing, Inc., 2010.", "Suggestive of their role in disease prevention, the active compounds in the guayusa plant, once harvested and concentrated to the correct ratio as described within the disclosure, demonstrate and provide enhanced beneficial effects in human health.", "SUMMARY OF THE INVENTION According to one aspect, the present disclosure relates to a process for extracting antioxidants from a plant, including contacting a plant material from a guayusa plant for a first time with a solvent, thereby obtaining a first slurry, filtering said first slurry, thereby obtaining a first extract, contacting said plant material for a second time with said solvent, thereby obtaining a second slurry, filtering said second slurry, thereby obtaining a second extract, combining said first extract and said second extract, thereby generating an third extract containing at least antioxidants, xanthines, and amino acids, and substantially drying said third extract.", "In another aspect, the present disclosure relates to an antioxidant mixture prepared by a process comprising the steps of: contacting a plant material from a guayusa plant for a first time with a solvent, thereby obtaining a first slurry, filtering said first slurry, thereby obtaining a first extract, contacting said plant material for a second time with said solvent, thereby obtaining a second slurry, filtering said second slurry, thereby obtaining a second extract, combining said first extract and said second extract, thereby generating an third extract containing at least antioxidants, xanthines, and amino acids, and substantially drying said third extract.", "BRIEF DESCRIPTION OF THE DRAWINGS The following FIGURE are included to illustrate certain aspects of the present invention, and should not be viewed as an exclusive embodiments.", "The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to one having ordinary skill in the art and the benefit of this disclosure.", "FIG. 1 is a prior art lab result, Antioxidant and Compounds Analysis of Guayusa tea, “Lab Number: 056939.”", "Advanced Botanical Consulting &", "Testing, Inc., 2010.", "DETAILED DESCRIPTION Definitions The term “filtration”", "is used to refer to either ultrafiltration or nanofiltration.", "In general, the “permeate”", "is the component that passes freely through the filter, while the “retentate”", "is the component that is retained by the filter.", "The term “microfiltration”", "refers to processes that use filtration membranes having larger pore size than both ultrafiltration and nanofiltration.", "Microfiltration involves subjecting the antioxidant extract or eluate to filtration through a filter having a pore size of less than about 0.50 μM.", "As used herein, the term “nanofiltration”", "refers to processes that use filtration membranes having a smaller molecular weight or pore size than those typically used in ultrafiltration processes.", "Like ultrafiltration, nanofiltration rejects a portion of the extract or eluate components above a certain molecular size while allowing those of a smaller size to pass through.", "Suitable nanofiltration membranes for use in the process disclosed herein are preferably made from polymers having a nominal molecular weight cut off of from about 700 Da to about 5000 Da (corresponding to pore sizes in the range of from about 17 A to about 40 A).", "Particularly preferred nanofiltration membranes are made from polymers having a nominal molecular weight cut off of from about 800 Da to about 2000 Da (corresponding to pore sizes in the range of from about 18 A to about 27 A).", "This pore size, in general, allows unoxidized phenolic compounds to pass through the membrane while retaining larger sized protein like compounds.", "As used herein, the term “plant material”", "means species of guayusa ( Ilex guayusa ), preferably the tea leaves.", "As used herein, the terms “antioxidant-containing eluate”", "and “antioxidant eluate”", "are used interchangeably to refer to the desired antioxidant-containing component collected after exposure to the adsorbent as described herein.", "Such adsorption step may be column adsorption, or any other adsorption means known to those having ordinary skill in the art.", "As used herein, the term “nutrient-rich extract”", "means an extract having a nutrient concentration of at least about 5 times, and preferably at least about 15 times, the starting composition based on the High-Performance Liquid Chromatography (“HPLC”) measurement, of the desired compounds (chlorogenic acids, xanthines, amino acids and flavonoids).", "As used herein, the term “antioxidant containing retentate”", "means the amino acid-containing components remaining on the upstream side of the filter after ultrafiltration or nanofiltration.", "Such amino acid-containing retentates are used as the source of polyphenols, flavonoids, xanthines and other water soluble vitamins.", "As used herein, the terms “amino acid-containing eluate,” “amino acid eluate”", "and “amino acid rich extract”", "are used interchangeably to refer to the desired amino acid-containing components collected after exposure to the adsorbent as described herein such as the L-theanine or luecine.", "Such adsorption step may be column adsorption, or any other adsorption means known to those having ordinary skill in the art.", "As used herein, the term “ultrafiltration”", "means a filtration method that uses an open filtration membrane with a pore size capable of allowing through molecules from at least about 10,000 Da to at least about 100,000 Da in molecular weight.", "Typically, ultrafiltration removes large molecular weight polysaccharides and proteins, but not oxidized phenolics.", "As used herein, the term “water,” means any of: deionized water, reverse osmosis water, distilled water, process water, ion exchange or mixtures thereof.", "All amounts, parts, ratios and percentages used herein are by weight unless otherwise specified.", "Process The first step in one embodiment of the presently disclosed process disclosed herein involves blanching the leaves by contacting the plant material with boiling water, preferably greater than 80° C., for approximately 30 seconds.", "In some embodiments, this step may also utilize other leaf pretreatment methods such as steam blanching, citric acid blanching or a convention withering step.", "However, in preferable embodiments, optimum conditions are met with non withered leaves to avoid any un-necessary oxidation of the phytochemicals prior to extraction.", "The blanched leaves are then contacted with a solvent to obtain an extract comprising the soluble antioxidants (flavonoids and cinnamic acids), xanthines, and amino acids.", "The plant material used in the present disclosure is guayusa ( Ilex guayusa ), and more preferably the guayusa leaves (other Ilex species with the particular nutrients desired may also be used, i.e. Ilex vomitoria ).", "The preferred extraction process involves steeping the guayusa leaves in and ethanol:hot water solution.", "The guayusa leaves are extracted using a 70:30 ethanol:hot water solution from about 70° C. to about 100° C. (from about 158 F. to about 212° F.), preferably from about 75° C. to about 90° C. (from about 167° F. to about 194° F.), and more preferably from about 80° C. to about 85° C. (from about 176° F. to about 185° F.), and a combined tea leaf to solvent ratio of about from 1:10 to about 1:20, i.e. for every 1 kg of guayusa leaves used, about 10 to 20 kg of solvent solution is used.", "Additionally, the extraction can be completed using a complete water extraction, supercritical extraction or similar however the yields of polyphenols and catechins and other active compounds will change.", "The guayusa leaves are soaked in the solvent between approximately 60 minutes to approximately 240 minutes, after which the wet leaves are filtered out through one or more layers of cheese cloth, or other similar straining material, and the antioxidant extract is collected.", "The wet leaves may then be re-extracted numerous additional times (preferably two or three more times) with another volume of hot water or a water solvent mixture and soaked for about 60 minutes to about 120 minutes further.", "The leaves are again filtered out and the nutrient rich extract collected.", "The filtered nutrient extracts can then combined and are ready for further processing or the second nutrient rich extract can be further processes itself, then combined with the first for a finished extract with ideal product specifications.", "Exposing Extract to Absorbent In one embodiment, the nutrient rich extract resulting from the previous step is subsequently exposed to an adsorbent, which separates the desired compounds from other associated substances, such as the pectins and fiber.", "The result is a nutrient rich containing eluate that is substantially free of the aforementioned associated insoluble compounds and impurities.", "The preferred method of carrying out this adsorption step is column chromatography.", "However, any similar method of separation commonly known to those skilled in the art is acceptable.", "For example, the nutrient rich extract and adsorbent may be combined in a solvent medium and mixed thoroughly or through a multistage supercritical extraction process.", "As previously mentioned, column chromatography is the preferred method to separate the desired extract from the other components in the nutrient rich extract.", "To separate via column chromatography, an inert column, preferably one made of glass or plastic, is first packed with an adsorbent or column packing.", "The adsorbent material may be any of a variety of hydrophobic cationic materials, however, polymeric resins, such as polyamides or polyclar are preferred.", "The column is then equilibrated with a solvent that is preferably water-soluble and does not form two phases when mixed with water.", "The solvent utilized in this phase of the process is preferably selected from water, ethanol, propylene glycol, glycerin, weak solutions of acetone, propanols, other like alcohols, and mixtures thereof.", "More preferably, the solvent comprises a mixture of water and ethanol.", "Still more preferably, the solvent mixture comprises less than about 80%, preferably less than about 70% ethanol, by weight of the solvent.", "In an alternate embodiment, the solvent comprises water.", "Next, the nutrient rich extract is pumped through the column and the components that are not adsorbed, or poorly adsorbed, i.e. amino acids, will be the first class of components to elute with the solvent.", "As the solvent strength is increased, such as, for example, through the addition of more ethanol, more strongly adsorbed components are released from the adsorbent material in the column and elute with the solvent.", "This process allows for the separation of the desired materials and the production of an amino acid rich-containing eluate having a composition containing at least approximately 5% total amino acids.", "Filtration of the Amino Acid-Containing Eluate The amino acid containing eluate is then subjected to a filtration step, to remove additional high molecular weight material, such as polysaccharides, pectins and fiber, and further enrich the nutritional concentration of the eluate.", "As defined above, this filtration step may be either ultrafiltration or nanofiltration.", "Each of these filtration processes is set forth below Nanofiltration involves contacting the amino acid eluate with a nanofiltration membrane to provide a filtered nutrient-rich extract.", "Nanofiltration according to the present disclosure removes the higher molecular weight materials such as polysaccharides, pectins and fibers.", "It is preferred that the nanofiltration step be carried out while the nutrient eluate is at a temperature of from about 30° C. to about 50° C. (about 86° F. to about 122° F.), preferably from about 35° C. to about 50° C. (about 95° F. to about 122° F.), and more preferably from about 45° C. to about 50° C. (about 113° F. to about 122° F.).", "Efficient nanofiltration is typically achieved by warming the nutrient eluate after exposure to the adsorbent material and just prior to nanofiltration.", "The pressure at which nanofiltration is carried out is preferably sufficiently high to provide adequate flow of the nutrient eluate through the membrane to achieve the desired processing.", "However, the pressure is preferably not so high as to remove substantial amounts of water from the system.", "According to the present disclosure, nanofiltration is typically carried out under a hydrostatic pressure of from about 100 psi to about 300 psi, preferably from about 180 psi to about 280 psi, applied to the upstream side of the membrane.", "Suitable nanofiltration membranes for use in the process of the present disclosure are made from polymers having a nominal molecular weight cut off of from about 700 Da to about 5000 Da (corresponding to pore sizes in the range of from about 17 A to about 40 A).", "Preferred nanofiltration membranes are made from polymers having a nominal molecular weight cut off of from about 800 Da to about 2000 Da (corresponding to pore sizes in the range of from about 18 A to about 27 A).", "Suitable polymers are those that have less affinity for the desired polyphenol I flavonoid components in the nutrient eluate.", "Polymers such as cellulose and the like are usually suitable for making these nanofiltration membranes.", "Typically, the resulting amino acid-rich extract is cooled to a temperature of about 16° C. (about 60° F.) or less.", "Similar to nanofiltration, ultrafiltration involves contacting the nutrient eluate with an ultrafiltration membrane to provide a filtered nutrient-rich extract.", "Ultrafiltration uses an open filtration membrane with a pore size capable of allowing through molecules from at least about 10,000 Da to at least about 100,000 Da in molecular weight.", "When utilizing ultrafiltration, the nutrient eluate can generally be filtered at a temperature of from about 30° C. to about 50° C. (about 86° F. to about 122° F.), preferably from about 35° C. to about 50° C. (about 95° F. to about 122° F.), and more preferably from about 45° C. to about 50° C. (about 113° F. to about 122° F.).", "Once the nutrient eluate is subjected to one of the aforementioned filtration processes the nutrient composition obtained contains not less than approximately 10% total amino acids.", "The resulting amino acid-rich extract can now be enriched with the antioxidant polyphenols and xanthines removed during the initial extraction and separation steps by combining the two concentrated extracts, where evaporation and drying can produce a finished extract that contains no less than 30% chlorogenic acids, 10% xanthines and 5% amino acids, or 45 w/w % total nutrients.", "More specifically, the finished extract contains no less than 40% chlorogenic acids, 15% xanthines and 10% amino acids, or 65 w/w % total nutrients.", "Using the Nutrient-Rich Extract After subjecting the plant material to one of the foregoing embodiments, the resulting nutrient-rich extract may then be used to lower the glycemic response of a subject in a more effective way than prior guayusa compositional function (see Swanston-Flatt, S K et.", "Al Glycaemic effects of traditional European plant treatments for diabetes.", "Studies in normal and streptozotocin diabetic mice.", "Diabetes Res.", "1989 February;", "10(2):69-73) and assist in mood enhancement, provide a natural source of energy, decrease the risk of cardiovascular disease, enhance brain function, assist with weight management and lower oxidative stress.", "The specific composition produced can provide an optimum source of natural energy that contains both an active element for enhanced metabolic function with its caffeine content while also assisting with glucose metabolism and regulation with the high level of chlorogenic acids.", "This ratio provides an ideal synergistic level of chlorogenic acids and caffeine to achieve effective weight loss benefits, whilst still shunting overactive insulin activity and hypertension typically associated with an increase in caffeine consumption.", "Further, the specific composition may provide a masking agent to control the astringent, brackish or bitter taste when formulating, add a level of sweetness to the product or allow for increased shelf stability by protecting or stabilizing the finished formulation from oxidation.", "EXAMPLES Example 1 The following examples are illustrative of embodiments disclosed herein.", "Parts and percentages are by dry weight unless otherwise indicated.", "It should be noted that these examples describe a wide range of conditions, which together with the above descriptions, illustrate the present disclosure in a non limiting fashion.", "About 400 g of commercial quality non withered guayusa tea leaves are extracted with about 1000 L of an ethanol:deionized water solution (70:30), at about 75° C. to about 85° C. (about 167° F. to about 186° F.) for approximately 120 minutes.", "The resulting slurry is filtered through two layers of muslin cloth and yields about 1200 g of crude tea extract.", "The residual leaves are re-extracted with deionized water under the foregoing conditions and again filtered through muslin cloth three more times.", "The tea extracts are combined and subjected to vacuum drying to concentrate the extract and remove additional impurities at about 80° C. until less than 3% moisture.", "The above semi solid extract is dissolved in ethanol then the top layer decanted.", "The top layer is then dried in a rotary drum dryer until less than 2% moisture.", "The final extract contains a profile of chlorogenic acids, catechins and caffeine for use as a nutritional ingredient in food and beverage applications.", "The final extract phytochemical profile is as seen in Table 1: TABLE 1 Serial No. Phyto-constituent Assay in w/w % Analysis method 1 Total Polyphenols 35 ± 0.5 w/w % Folin-Ciocalteu by spectrophotometric method 2 Total Chlorogenic 32 ± 0.35 w/w % LCMS/MS method acids 3 Caffeine 26 ± 0.25 w/w % LCMS/MS method 4 Theobromine 0.0215 ± 0.005 w/w % LCMS/MS method 5 L-Theanine 0.011 ± 0.003 w/w % LCMS/MS method Example 2 About 200 g of commercial quality guayusa tea leaves are extracted with about 550 L of an ethanol:deionized water solution (70:30), at about 75° C. to about 85° C. (about 167° F. to about 186° F.) for approximately 120 minutes.", "The resulting slurry is filtered through two layers of muslin cloth and yields about 1200 g of crude tea extract.", "The residual leaves are re-extracted with deionized water under the foregoing conditions and again filtered through muslin cloth.", "The tea extracts are combined and subjected to microfiltration via a 0.45 μM pleated filter (1.5 ft.", "sup[.", "].2, acrylic co-polymer on a polypropylene-polyester support).", "The resulting permeate is then subjected to nanofiltration using a Millipore® 1000 Dalton Molecular Weight Cut Off (MWCO) filter.", "The resulting permeate is then used to produce a clarified tea extract which contain the chlorogenic acids, xanthines and other phenols.", "The retentates from these filtrations, which contain the amino acids and glycosides, are combined to yield an amino acid-containing retentate with a volume of about 300 ml and about S0 Bx.", "This extract has an active concentration of about 600 mg/L.", "The nutrient rich extract is diluted with deionized water in a 1:1 ratio, and used as feed in the next step.", "Amberlite XAD 16HP® (Rohm &", "Haas) is packed in a column (2.5 cm ID.", "times[.", "].75 cm height) to give a column volume of about 350 ml.", "The column is washed with about 4-5 column volumes of deionized water.", "The diluted nutrient extract from the foregoing extraction step is pumped into the column until breakthrough occurs (about 100 ml).", "The column is first eluted with deionized water to remove the non-phenolic materials including amino acids and other polysaccharides.", "When the eluate gives no precipitate or a clouding reaction with ethanol, the water elution is stopped.", "This eluate contains about 200 mg/L amino acids and about 10 mg/ml tea polysaccharides.", "It is then nanofiltered using a 1000 Dalton MWCO membrane to separate the high molecular weight non-phenolic materials from amino acids.", "The amino acid-rich extract is then added to the clarified polyphenol tea extract and further concentrated under vacuum until dry to remove any residual solvents and impurities.", "The finished substrate is then solubilized in a distilled solution and dried in a rotary evaporator to produce an extract of less than approximately 3% moisture.", "The final extract phytochemical profile is as seen in Table 2: TABLE 2 Serial No. Phyto-constituent Assay in w/w % Analysis method 1 Total Polyphenols 47.1 ± 1.5 w/w % Folin-Ciocalteu by spectrophotometric method 2 Total Chlorogenic 41.5 ± 0.35 w/w % LCMS/MS method acids 3 Caffeine 36.8 ± 0.25 w/w % LCMS/MS method 4 Catechins 7.2 ± 0.05 w/w % LCMS/MS method 5 L-Theanine 1.40 ± 0.04 w/w % LCMS/MS method 6 Theobromine 0.266 ± 0.007 w/w % LCMS/MS method Example 3 200 grams of non-withered Guayusa tea leaves are extracted with an Ethanol:water mixture (95:5) at 55° C. to about 65° C. The water to tea leaves ratio is about 15:1.", "This extraction is continued for about 2 hours, and the resulting nutrient dense extract is filtered using a filtration funnel with a waterman filtering paper.", "The residual tea leaves are then extracted twice more with an ethanol:water solvent at a ratio of 90:10, and this second and third nutrient extracts 2 and 3 are passed through filtration using whatman filter paper to remove any residual tea powder residue.", "The three nutrient extracts are combined, and the total active content in them is determined to be about 220 mg/L.", "The combined extracts are send through a buchi rotary evaporator vacuum pump to concentrate the extract and remove any residual solvents.", "The semi-solid extract is completely dried using a savant speedvac vacuum system.", "The final extract provides a nutrient dense substrate containing the optimum combination of antioxidants and caffeine for use as a nutritional component in foods, beverages and supplements.", "The final extract phytochemical profile is as seen in Table 3: TABLE 3 Serial No. Analysis Amount Method 1 Total Polyphenols 22.3 ± 1.5 w/w % Folin-Ciocalteu by spectrophotometric method 2 Total Chlorogenic 21.1 ± 0.35 w/w % LCMS/MS method acids 3 Caffeine 17.6 ± 0.15 w/w % LCMS/MS method 4 Catechins 1.5 ± 0.05 w/w % LCMS/MS method 5 L-Theanine 0.002 ± 0.04 w/w % LCMS/MS method 6 Theobromine 0.165 ± 0.007 w/w % LCMS/MS method Example 4 Seven female subjects, ages 29-45, were given 300 mg of guayusa extract containing 42% chlorogenic acid, 16% xanthines and 12% amino acids orally for 3 weeks.", "Subjects were measured at the onset and upon final administration for Nuerotransmitter levels of Serotonin, GABA, Dopamine, Norepinephrine, Epinephrine, Glutamate and Creatinine Results demonstrate an increase in Serotonin and GABA levels by 22% and 26% respectively, and an increase in of Dopamine, Norephipephrine, Epinephrine by 12%, 11% and 15%.", "Glutamate and Creatinine levels remained unchanged.", "Example 5 Two sets of six ready-to-drink tea beverages were prepared by steeping conventional green tea leaves in water at a 1:1 ratio for ten minutes, filtering, pasteurizing, then bottling.", "With one set, prior to bottling, 200 mg of guayusa extract was added that contained 32% chlorogenic acid, 16% xanthines and 5% amino acids and 30% total glycosides.", "Packaging was carried out in conventional 500 ml RTD glass bottles and sealed with PTFE screw lined caps.", "The tea beverages were stored for a period of 12 weeks in a temperature controlled light deprived container.", "One sample from each set was analyzed over the 12 weeks period for total flavonol glycoside concentration and total EGCG concentration.", "Over the 12 weeks period, the control set containing no guayusa reduced total glycoside concentration by 37% and total EGCG concentration by 40% with most of the degration during the last two weeks of the study, week 10-week 12.", "Over the same 12 week period the six green tea beverages containing the 200 mg of guayusa extract per 500 ml seen an average decrease in total glycosides of 2% and a total average decrease in EGCG of 8%.", "In addition sensory scores completed on both sets indicated an increase in overall product taste as sweetness score by 92% of the sensory evaluations.", "Although the present disclosure has been described with reference to specific embodiments, this description is not meant to be construed in a limited sense.", "Various modifications of the disclosed embodiments, as well as alternative embodiments of the disclosure will become apparent to persons skilled in the art upon the reference to the description of the present disclosure.", "It is, therefore, contemplated that the appended claims will cover modifications that fall within the scope of the disclosure." ]
CROSS REFERENCE TO RELATED APPLICATIONS (Not Applicable) STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT (Not Applicable) BACKGROUND OF THE INVENTION 1. Technical Field This invention relates to the field of computer speech navigation and more particularly to a method and apparatus for speech enabling labeless controls in an existing graphical user interface. 2. Description of the Related Art Speech recognition, also referred to as speech-to-text, is technology that enables a computer to transcribe spoken words into computer recognized text equivalents. Speech recognition is the process of converting an acoustic signal, captured by a transducive element, such as a microphone or a telephone, to a set of words. Subsequently, these words can be used for speech navigation and speech dictation. Though the use of speech recognition for speech dictation has flourished, the transparent application of speech navigation to a graphical user interface for speech command and control lags behind. Originally, speech application developers accomplished speech navigation by associating a discrete number of commands available in a graphical user interface with command and control macros. In turn, speech application developers assigned to each command and control macro a corresponding speech command. Thus, a speech navigation system user's utterance invoked a particular command and control macro associated with a command in the graphical user interface. Still, the command specific nature of the speech user interface inhibited its generic application to customized graphical user interfaces. Notably a graphical user interface could include interface objects capable of performing at least one action, for example a button or a list box. Unless the speech developer was aware of each control in a graphical user interface, those controls unknown to the speech developer remained separate from the speech navigation system. Hence, past speech navigation systems lacked portability. Recently, speech recognition systems have integrated speech navigation, at least as applied to standard graphical user interface controls. Using an accessibility interface, for instance Microsoft® Active Accessibility®, speech developers can provide a more seamless interface between the speech navigation system and the graphical user interface. By way of example, Active Accessibility® can supply a speech navigation system with a wide variety of information concerning controls such as toolbars, buttons and menus in a program's graphical user interface. Using an accessibility interface, speech developers can dynamically assign speech commands to individual controls according to information provided to the speech navigation system by the accessibility interface. In consequence, when a user invokes a window containing a set of controls, the speech navigation system, using the accessibility interface, can query the window for its contents identifying each control. Subsequently, the speech navigation system can assign corresponding standard speech commands according to the identity of each control. Still, present speech navigation systems cannot properly supply an appropriate speech command for labeless controls not recognized by an accessibility interface. Specifically, present speech navigation systems cannot properly supply an appropriate speech command for controls not having an inherent label. As a result, in a window containing labeless controls in addition to standard controls, the accessibility interface can report only the identity of the standard controls. The speech navigation system will remain ineffective as to each labeless control. Thus, present systems do not provide a complete integration between the speech navigation system and the graphical user interface. SUMMARY OF THE INVENTION A system for extending the range of speech commands to labeless controls in an existing graphical user interface in accordance with the inventive arrangement satisfies the long-felt need of the prior art by providing a complete integration between the speech navigation system and the graphical user interface. Thus, the inventive arrangements provide a method and system for speech enabling labeless controls in an existing graphical user interface. The inventive arrangements have advantages over all known speech enabling methods used to speech enable graphical user interface controls, and provides a novel and nonobvious system, including apparatus and method, for speech enabling labeless controls in an existing graphical user interface. A method for speech enabling labeless controls in an existing graphical user interface can comprise the steps of: identifying controls in a window contained in the graphical user interface; testing each identified control for an associated label; for each identified control having an associated label, adding the associated label to an active grammar of a speech recognition system; for each identified control not having an associated label, creating a label based upon object properties of contextual relevant user interface objects, for instance those object positioned proximate to the identified control; and, further adding each created label to the active grammar. In testing each identified control for an associated label, an accessibility interface query can be applied to each identified control in the window. In addition, in creating the label, each contextually relevant object can be searched for an object property descriptive of the identified control not having an associated label. Subsequently, a label can be formed based upon the descriptive object property found in the searching step. A method for speech enabling labeless controls in an existing graphical user interface can further comprise the steps of: for each identified control not having a created label based upon an object property of contextually relevant object found in the searching step, determining whether the identified control has a default action; assigning a generic label to the identified control having a default action; associating the determined default action with the assigned label; and, adding the assigned label corresponding to the default action to the active grammar. Additionally, for each identified control having multiple actions with no clear default action, the method can further include the steps of forming a help panel with information about speech commands accessible for that identified control; and, assigning the help panel as the default action. BRIEF DESCRIPTION OF THE DRAWINGS There are presently shown in the drawings embodiments which are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. FIG. 1 is a pictorial representation of a computer system with audio capabilities on which the method of the invention can be used. FIG. 2 is a block diagram showing a typical high level architecture for the computer system in FIG. 1 . FIGS. 3A-3C, taken together, are a flow chart illustrating the inventive method. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a typical computer system 1 for use in conjunction with the present invention. The system preferably comprises a computer 3 including a central processing unit (CPU), fixed disk 8 A, and internal memory device 8 B. The system also includes a microphone 7 operatively connected to the computer system through suitable interface circuitry or “sound board” (not shown), a keyboard 5 , and at least one user interface display unit 2 such as a video data terminal (VDT) operatively connected thereto. The CPU can comprise any suitable microprocessor or other electronic processing unit, as is well known to those skilled in the art. An example of such a CPU would include the Pentium or Pentium II brand microprocessor available from Intel Corporation, or any similar microprocessor. Speakers 4 , as well as an interface device, such as mouse 6 , can also be provided with the system, but are not necessary for operation of the invention as described herein. The various hardware requirements for the computer system as described herein can generally be satisfied by any one of many commercially available high speed multimedia personal computers offered by manufacturers such as International Business Machines (IBM), Compaq, Hewlett Packard, or Apple Computers. FIG. 2 illustrates a presently preferred architecture for a speech navigation system in computer 1 . As shown in FIG. 2, the system can include an operating system 9 , a speech navigation system 10 in accordance with the inventive arrangements, and a graphical user interface 11 . A speech enabled application 12 can also be provided. In FIG. 2, the speech navigation system 10 , the graphical user interface 11 , and the speech enabled application 12 are shown as separate application programs. It should be noted, however, that the invention is not limited in this regard, and these various applications could, of course, be implemented as a single, more complex applications program. As shown in FIG. 2, computer system 1 includes one or more computer memory devices 8 , preferably an electronic random access memory 8 B and a bulk data storage medium, such as a fixed disk drive 8 A. In a presently preferred embodiment described herein, operating system 9 is one of the Windows family of operating systems, such as Windows NT, Windows 95 or Windows 98 which are available from Microsoft Corporation of Redmond, Wash. However, the system is not limited in this regard, and the invention can also be used with any other type of computer operating system. The system as disclosed herein can be implemented by a programmer, using commercially available development tools for the operating systems described above. In the present invention, audio signals representative of sound received in microphone 7 are processed within computer 1 using conventional computer audio circuitry so as to be made available to operating system 9 in digitized form. The audio signals received by the computer 1 are conventionally provided to the speech navigation system 10 via the computer operating system 9 in order to perform speech recognition functions. As in conventional speech recognition systems, the audio signals are processed by the speech navigation system 10 to identify speech commands spoken by a user into microphone 7 . Recognized speech commands subsequently can be converted to corresponding system commands in the graphical user interface 11 associated with the speech enabled application 12 . FIGS. 3A-3C, taken together, are a flow chart illustrating a process for speech enabling labeless controls in an existing graphical user interface. In FIG. 3A, the method in accordance with the inventive arrangements begins in block 20 upon a window becoming the exclusive active window in the foreground of the graphical user interface 12 , commonly referred to as obtaining focus. Following path 21 to decision block 22 , the process continues only if unidentified objects remain in the active window. Continuing along path 23 to block 24 , the next unidentified object in the window is identified and, in block 26 , tested to determine if the object is a control suitable for speech navigation. If the object is determined not to be a control, returning along paths 39 and 33 to decision block 22 , the process can repeat, if necessary. If, in block 26 , the object is determined to be a control, following path 27 to decision block 86 , it is further determined whether the control has multiple actions and no clear default action. If the control is determined to have a single action, or a clear default action in decision block 86 , the method continues along path 87 to decision block 28 . Alternatively, if the control has multiple actions and no clear default action, following path 79 to block 80 , a help panel can be formed to include information pertaining to the standard speech commands available for use with the particular class of controls corresponding to the subject control. For instance, the help panel for a list-box type control could include “Scroll Up”, “Scroll-Down”, or “Enter-Key”. Moreover, following path 81 to block 82 , the newly formed help panel can be assigned to the subject control. Finally, the presentation of the help panel is assigned to the control as the default action in block 84 . In this way, the user can be informed of possible speech commands consistent with the subject control. Continuing along path 85 to decision block 28 , the control can be queried for a corresponding label. Specifically, each control can be queried through the use of an accessibility interface provided by Microsoft® Active Accessibility®. Active Accessibility® is based on the Component Object Model (COM), the Microsoft®-developed industry standard that defines a common way for applications and operating systems to communicate. In an Active Accessibility® application, sometimes referred to as a server, the server can provide information about the contents of the computer screen that is within the server's control. Accessibility aids, referred to as clients, use Active Accessibility® to obtain information about the user interface of other applications and the operating system. With Active Accessibility®, user interface elements are exposed to clients as COM objects. These accessible objects maintain pieces of information, called properties, which describe the object's name, screen location, and other information needed by accessibility aids. Accessible objects also provide methods, which are functions that clients can call to cause the object to perform some action. Accessible objects are implemented using Active Accessibility®'s COM-based IAccessible interface. This interface includes functions such as IAccessible::get_accName and IAccessible::accLocation, which allow clients to examine an object's properties. The interface also provides methods such as IAccessible::accDoDefaultAction and IAccessible::accHitTest, which clients can call to cause the object to perform some action. Clients obtain information about or interact with an object by calling the IAccessible properties and methods. Thus, in decision block 28 , a control identified in decision block 26 can be queried for a corresponding label using IAccessible::get_accName. If the Active Accessibility® interface returns a label, following path 31 to block 30 , the label can be added to the active grammar of the speech navigation system. Returning along path 33 to decision block 22 , the next object can be tested unless no more unidentified objects remain in the active window. Accordingly, following path 37 to block 32 , the process terminates. In contrast, if in decision block 28 the Active Accessibility® interface fails to return a label, following path 29 to jump circle B, contextually relevant user interface objects, for instance objects proximate to the labeless control, can be examined for object properties pertinent to the identity of the labeless control. Specifically, in FIG. 3B, following path 41 from jump circle B to decision block 40 , the process can continue so long as unidentified contextually relevant objects remain. If unidentified contextually relevant objects remain to be inspected, the process continues along path 45 to block 42 in which the object properties of each contextually relevant object are inspected for a potential label. Following path 47 to decision block 44 , the next contextually relevant object can be examined if the process fails to uncover a descriptive object property in the present contextually relevant object. If, however, a descriptive property is found in a contextually relevent object in decision block 44 , continuing along path 49 to block 46 , a label can be created using the uncovered descriptive object property. Subsequently, following path 51 to block 48 , the created label can be added to the active grammar of the speech navigation system before returning along path 53 to jump circle A to decision block 22 in FIG. 3A, whereupon the next window object can be identified and labeled, if necessary. But, if all contextually relevant objects have been identified in decision block 40 , yet none provide a descriptive object property useful in the creation of a label for the control, then following path 43 to jump circle C, a default method can provide an appropriate mechanism suitable for speech navigation which can be associated with the subject labeless control as a label substitute. FIG. 3C illustrates the default method for providing a substitute label for unhandled labeless controls. From jump circle C, leading to block 68 along path 61 , a speech command can be associated with the labeless control corresponding to the labeless control's default action. Following path 67 to block 64 , a numeric label can be assigned to the labeless control as a label. Finally, following path 71 to block 66 , the assigned label is added to the active grammar. Subsequently, the process can return along path 73 to jump circle A to decision block 22 in FIG. 3A, whereupon the next window object can be identified and labeled, if necessary. Having assigned a label or label substitute to each control and labeless control in the active window, the speech navigation system 10 in coordination with graphical user interface 12 can display each label in or near the controls to which they apply. If labeling obstructs the view of objects in the active window, a symbol, for instance a transparent image of a speech bubble with a line therethrough, or a small red dot, can be positioned proximate to the control. The symbol can indicate to the user that the user must take an affirmative action to display the controls. The affirmative action can be a click of mouse 6 , or a tap of a key in keyboard 5 . Furthermore, the affirmative action could be the speech command, “Show Me What To Say.” Upon receiving the affirmative command, the labels can be displayed until the user either issues a speech command affecting a control in the active window, issues a speech command to hide the labels, or until a reasonable timeout period, for instance one minute, elapses. As an alternative, each label can be drawn transparently over the label's corresponding control so as to not obscure important graphical information. When the speech navigation system 10 receives a speech command corresponding to a label associated with a control in the active window, the speech navigation system 10 can execute the single function associated with that control. In contrast, where the control associated with the invoked label is more complex and can respond to several speech commands, the help panel containing information about each speech command pertaining to a control aspect of the object can be displayed. In any event, however, each control contained in the active window, including labeless controls, can be manipulated by the speech navigation system 10 . Hence, the present inventive method provides a complete integration between the speech navigation system 10 and the graphical user interface 12 .
A method for speech enabling labeless controls in an existing graphical user interface can comprise the steps of: identifying controls in a window contained in the graphical user interface; testing each identified control for an associated label; for each identified control having an associated label, adding the associated label to an active grammar of a speech recognition system; for each identified control not having an associated label, creating a label based upon an object property of a contextually relevant user interface object; and, further adding each created label to the active grammar. In testing each identified control for an associated label, an accessibility interface query can be applied to each identified control in the window. In addition, in creating the label, each contextually relevant object can be searched for an object property descriptive of the identified control not having an associated label. Subsequently, a label can be formed based upon the descriptive object property found in the searching step.
Briefly summarize the invention's components and working principles as described in the document.
[ "CROSS REFERENCE TO RELATED APPLICATIONS (Not Applicable) STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT (Not Applicable) BACKGROUND OF THE INVENTION 1.", "Technical Field This invention relates to the field of computer speech navigation and more particularly to a method and apparatus for speech enabling labeless controls in an existing graphical user interface.", "Description of the Related Art Speech recognition, also referred to as speech-to-text, is technology that enables a computer to transcribe spoken words into computer recognized text equivalents.", "Speech recognition is the process of converting an acoustic signal, captured by a transducive element, such as a microphone or a telephone, to a set of words.", "Subsequently, these words can be used for speech navigation and speech dictation.", "Though the use of speech recognition for speech dictation has flourished, the transparent application of speech navigation to a graphical user interface for speech command and control lags behind.", "Originally, speech application developers accomplished speech navigation by associating a discrete number of commands available in a graphical user interface with command and control macros.", "In turn, speech application developers assigned to each command and control macro a corresponding speech command.", "Thus, a speech navigation system user's utterance invoked a particular command and control macro associated with a command in the graphical user interface.", "Still, the command specific nature of the speech user interface inhibited its generic application to customized graphical user interfaces.", "Notably a graphical user interface could include interface objects capable of performing at least one action, for example a button or a list box.", "Unless the speech developer was aware of each control in a graphical user interface, those controls unknown to the speech developer remained separate from the speech navigation system.", "Hence, past speech navigation systems lacked portability.", "Recently, speech recognition systems have integrated speech navigation, at least as applied to standard graphical user interface controls.", "Using an accessibility interface, for instance Microsoft® Active Accessibility®, speech developers can provide a more seamless interface between the speech navigation system and the graphical user interface.", "By way of example, Active Accessibility® can supply a speech navigation system with a wide variety of information concerning controls such as toolbars, buttons and menus in a program's graphical user interface.", "Using an accessibility interface, speech developers can dynamically assign speech commands to individual controls according to information provided to the speech navigation system by the accessibility interface.", "In consequence, when a user invokes a window containing a set of controls, the speech navigation system, using the accessibility interface, can query the window for its contents identifying each control.", "Subsequently, the speech navigation system can assign corresponding standard speech commands according to the identity of each control.", "Still, present speech navigation systems cannot properly supply an appropriate speech command for labeless controls not recognized by an accessibility interface.", "Specifically, present speech navigation systems cannot properly supply an appropriate speech command for controls not having an inherent label.", "As a result, in a window containing labeless controls in addition to standard controls, the accessibility interface can report only the identity of the standard controls.", "The speech navigation system will remain ineffective as to each labeless control.", "Thus, present systems do not provide a complete integration between the speech navigation system and the graphical user interface.", "SUMMARY OF THE INVENTION A system for extending the range of speech commands to labeless controls in an existing graphical user interface in accordance with the inventive arrangement satisfies the long-felt need of the prior art by providing a complete integration between the speech navigation system and the graphical user interface.", "Thus, the inventive arrangements provide a method and system for speech enabling labeless controls in an existing graphical user interface.", "The inventive arrangements have advantages over all known speech enabling methods used to speech enable graphical user interface controls, and provides a novel and nonobvious system, including apparatus and method, for speech enabling labeless controls in an existing graphical user interface.", "A method for speech enabling labeless controls in an existing graphical user interface can comprise the steps of: identifying controls in a window contained in the graphical user interface;", "testing each identified control for an associated label;", "for each identified control having an associated label, adding the associated label to an active grammar of a speech recognition system;", "for each identified control not having an associated label, creating a label based upon object properties of contextual relevant user interface objects, for instance those object positioned proximate to the identified control;", "and, further adding each created label to the active grammar.", "In testing each identified control for an associated label, an accessibility interface query can be applied to each identified control in the window.", "In addition, in creating the label, each contextually relevant object can be searched for an object property descriptive of the identified control not having an associated label.", "Subsequently, a label can be formed based upon the descriptive object property found in the searching step.", "A method for speech enabling labeless controls in an existing graphical user interface can further comprise the steps of: for each identified control not having a created label based upon an object property of contextually relevant object found in the searching step, determining whether the identified control has a default action;", "assigning a generic label to the identified control having a default action;", "associating the determined default action with the assigned label;", "and, adding the assigned label corresponding to the default action to the active grammar.", "Additionally, for each identified control having multiple actions with no clear default action, the method can further include the steps of forming a help panel with information about speech commands accessible for that identified control;", "and, assigning the help panel as the default action.", "BRIEF DESCRIPTION OF THE DRAWINGS There are presently shown in the drawings embodiments which are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.", "FIG. 1 is a pictorial representation of a computer system with audio capabilities on which the method of the invention can be used.", "FIG. 2 is a block diagram showing a typical high level architecture for the computer system in FIG. 1 .", "FIGS. 3A-3C, taken together, are a flow chart illustrating the inventive method.", "DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a typical computer system 1 for use in conjunction with the present invention.", "The system preferably comprises a computer 3 including a central processing unit (CPU), fixed disk 8 A, and internal memory device 8 B. The system also includes a microphone 7 operatively connected to the computer system through suitable interface circuitry or “sound board”", "(not shown), a keyboard 5 , and at least one user interface display unit 2 such as a video data terminal (VDT) operatively connected thereto.", "The CPU can comprise any suitable microprocessor or other electronic processing unit, as is well known to those skilled in the art.", "An example of such a CPU would include the Pentium or Pentium II brand microprocessor available from Intel Corporation, or any similar microprocessor.", "Speakers 4 , as well as an interface device, such as mouse 6 , can also be provided with the system, but are not necessary for operation of the invention as described herein.", "The various hardware requirements for the computer system as described herein can generally be satisfied by any one of many commercially available high speed multimedia personal computers offered by manufacturers such as International Business Machines (IBM), Compaq, Hewlett Packard, or Apple Computers.", "FIG. 2 illustrates a presently preferred architecture for a speech navigation system in computer 1 .", "As shown in FIG. 2, the system can include an operating system 9 , a speech navigation system 10 in accordance with the inventive arrangements, and a graphical user interface 11 .", "A speech enabled application 12 can also be provided.", "In FIG. 2, the speech navigation system 10 , the graphical user interface 11 , and the speech enabled application 12 are shown as separate application programs.", "It should be noted, however, that the invention is not limited in this regard, and these various applications could, of course, be implemented as a single, more complex applications program.", "As shown in FIG. 2, computer system 1 includes one or more computer memory devices 8 , preferably an electronic random access memory 8 B and a bulk data storage medium, such as a fixed disk drive 8 A. In a presently preferred embodiment described herein, operating system 9 is one of the Windows family of operating systems, such as Windows NT, Windows 95 or Windows 98 which are available from Microsoft Corporation of Redmond, Wash.", "However, the system is not limited in this regard, and the invention can also be used with any other type of computer operating system.", "The system as disclosed herein can be implemented by a programmer, using commercially available development tools for the operating systems described above.", "In the present invention, audio signals representative of sound received in microphone 7 are processed within computer 1 using conventional computer audio circuitry so as to be made available to operating system 9 in digitized form.", "The audio signals received by the computer 1 are conventionally provided to the speech navigation system 10 via the computer operating system 9 in order to perform speech recognition functions.", "As in conventional speech recognition systems, the audio signals are processed by the speech navigation system 10 to identify speech commands spoken by a user into microphone 7 .", "Recognized speech commands subsequently can be converted to corresponding system commands in the graphical user interface 11 associated with the speech enabled application 12 .", "FIGS. 3A-3C, taken together, are a flow chart illustrating a process for speech enabling labeless controls in an existing graphical user interface.", "In FIG. 3A, the method in accordance with the inventive arrangements begins in block 20 upon a window becoming the exclusive active window in the foreground of the graphical user interface 12 , commonly referred to as obtaining focus.", "Following path 21 to decision block 22 , the process continues only if unidentified objects remain in the active window.", "Continuing along path 23 to block 24 , the next unidentified object in the window is identified and, in block 26 , tested to determine if the object is a control suitable for speech navigation.", "If the object is determined not to be a control, returning along paths 39 and 33 to decision block 22 , the process can repeat, if necessary.", "If, in block 26 , the object is determined to be a control, following path 27 to decision block 86 , it is further determined whether the control has multiple actions and no clear default action.", "If the control is determined to have a single action, or a clear default action in decision block 86 , the method continues along path 87 to decision block 28 .", "Alternatively, if the control has multiple actions and no clear default action, following path 79 to block 80 , a help panel can be formed to include information pertaining to the standard speech commands available for use with the particular class of controls corresponding to the subject control.", "For instance, the help panel for a list-box type control could include “Scroll Up”, “Scroll-Down”, or “Enter-Key.”", "Moreover, following path 81 to block 82 , the newly formed help panel can be assigned to the subject control.", "Finally, the presentation of the help panel is assigned to the control as the default action in block 84 .", "In this way, the user can be informed of possible speech commands consistent with the subject control.", "Continuing along path 85 to decision block 28 , the control can be queried for a corresponding label.", "Specifically, each control can be queried through the use of an accessibility interface provided by Microsoft® Active Accessibility®.", "Active Accessibility® is based on the Component Object Model (COM), the Microsoft®-developed industry standard that defines a common way for applications and operating systems to communicate.", "In an Active Accessibility® application, sometimes referred to as a server, the server can provide information about the contents of the computer screen that is within the server's control.", "Accessibility aids, referred to as clients, use Active Accessibility® to obtain information about the user interface of other applications and the operating system.", "With Active Accessibility®, user interface elements are exposed to clients as COM objects.", "These accessible objects maintain pieces of information, called properties, which describe the object's name, screen location, and other information needed by accessibility aids.", "Accessible objects also provide methods, which are functions that clients can call to cause the object to perform some action.", "Accessible objects are implemented using Active Accessibility®'s COM-based IAccessible interface.", "This interface includes functions such as IAccessible::get_accName and IAccessible::accLocation, which allow clients to examine an object's properties.", "The interface also provides methods such as IAccessible::accDoDefaultAction and IAccessible::accHitTest, which clients can call to cause the object to perform some action.", "Clients obtain information about or interact with an object by calling the IAccessible properties and methods.", "Thus, in decision block 28 , a control identified in decision block 26 can be queried for a corresponding label using IAccessible::get_accName.", "If the Active Accessibility® interface returns a label, following path 31 to block 30 , the label can be added to the active grammar of the speech navigation system.", "Returning along path 33 to decision block 22 , the next object can be tested unless no more unidentified objects remain in the active window.", "Accordingly, following path 37 to block 32 , the process terminates.", "In contrast, if in decision block 28 the Active Accessibility® interface fails to return a label, following path 29 to jump circle B, contextually relevant user interface objects, for instance objects proximate to the labeless control, can be examined for object properties pertinent to the identity of the labeless control.", "Specifically, in FIG. 3B, following path 41 from jump circle B to decision block 40 , the process can continue so long as unidentified contextually relevant objects remain.", "If unidentified contextually relevant objects remain to be inspected, the process continues along path 45 to block 42 in which the object properties of each contextually relevant object are inspected for a potential label.", "Following path 47 to decision block 44 , the next contextually relevant object can be examined if the process fails to uncover a descriptive object property in the present contextually relevant object.", "If, however, a descriptive property is found in a contextually relevent object in decision block 44 , continuing along path 49 to block 46 , a label can be created using the uncovered descriptive object property.", "Subsequently, following path 51 to block 48 , the created label can be added to the active grammar of the speech navigation system before returning along path 53 to jump circle A to decision block 22 in FIG. 3A, whereupon the next window object can be identified and labeled, if necessary.", "But, if all contextually relevant objects have been identified in decision block 40 , yet none provide a descriptive object property useful in the creation of a label for the control, then following path 43 to jump circle C, a default method can provide an appropriate mechanism suitable for speech navigation which can be associated with the subject labeless control as a label substitute.", "FIG. 3C illustrates the default method for providing a substitute label for unhandled labeless controls.", "From jump circle C, leading to block 68 along path 61 , a speech command can be associated with the labeless control corresponding to the labeless control's default action.", "Following path 67 to block 64 , a numeric label can be assigned to the labeless control as a label.", "Finally, following path 71 to block 66 , the assigned label is added to the active grammar.", "Subsequently, the process can return along path 73 to jump circle A to decision block 22 in FIG. 3A, whereupon the next window object can be identified and labeled, if necessary.", "Having assigned a label or label substitute to each control and labeless control in the active window, the speech navigation system 10 in coordination with graphical user interface 12 can display each label in or near the controls to which they apply.", "If labeling obstructs the view of objects in the active window, a symbol, for instance a transparent image of a speech bubble with a line therethrough, or a small red dot, can be positioned proximate to the control.", "The symbol can indicate to the user that the user must take an affirmative action to display the controls.", "The affirmative action can be a click of mouse 6 , or a tap of a key in keyboard 5 .", "Furthermore, the affirmative action could be the speech command, “Show Me What To Say.”", "Upon receiving the affirmative command, the labels can be displayed until the user either issues a speech command affecting a control in the active window, issues a speech command to hide the labels, or until a reasonable timeout period, for instance one minute, elapses.", "As an alternative, each label can be drawn transparently over the label's corresponding control so as to not obscure important graphical information.", "When the speech navigation system 10 receives a speech command corresponding to a label associated with a control in the active window, the speech navigation system 10 can execute the single function associated with that control.", "In contrast, where the control associated with the invoked label is more complex and can respond to several speech commands, the help panel containing information about each speech command pertaining to a control aspect of the object can be displayed.", "In any event, however, each control contained in the active window, including labeless controls, can be manipulated by the speech navigation system 10 .", "Hence, the present inventive method provides a complete integration between the speech navigation system 10 and the graphical user interface 12 ." ]
FIELD OF THE INVENTION The present invention relates to a system and method for automatically executing securities trades based upon a series of user-definable rules. BACKGROUND OF THE INVENTION Under existing equities trading systems, a trader needs to review every order, including small orders, and make a decision as to whether to send the order to an exchange or to fill the order from the inventory of the brokerage. For certain orders, for example where the client has asked for a limit order, the trader would need to review the order and perform an action on it. While this arrangement provides for accurate order placement, it lengthens the time between when the order is placed and when the order is filled due to the review process undertaken by the trader. In an environment where market movements may be large and rapid, short execution times are critical in obtaining the best possible price for a trade. Combine the rapidly-moving markets with computer-enabled order placement, and customers desire (and often expect) to have their orders executed as soon as possible after being placed. By requiring the trader to manually review each order and make a decision thereon, the execution time of the order is inherently slow. It is therefore desirable to shorten the time between when an order is placed and when the order is executed. The system and method of the present invention are designed to overcome the limitations in the prior art. SUMMARY OF THE INVENTION By using the system and method of the present invention, a trader can set some basic rules for all orders, so that the trader does not need to take any action on an order if it meets the pre-defined criteria. If the order fails to meet the criteria, then the trader will directly act upon the order; otherwise, all orders will be automatically processed which will shorten execution time. The system is most effective with small orders which are easily filled. By freeing up some of the trader's time, he or she can concentrate on the larger orders that are more difficult to fill. An order that is entered into the system of the present invention can be handled in one of three ways: (1) worked by the trader in the same manner as a typical telephone order; (2) automatically filled from the brokerage's inventory; or (3) automatically forwarded to a trading exchange to be filled. An order will be automatically processed only if certain pre-defined criteria are met. This is accomplished by passing an order through a series of filters; if the order passes through all the filters, then it will be automatically processed. If an order does not meet all of the filters, it will be passed out of the filter loop to a trader to be manually processed. An automated securities order execution system according to the present invention includes order entering means for a client to enter an order and at least one filtering means for determining whether the order can be automatically executed. After the filtering means have been applied, routing means will route the order to a destination based upon the determination made by the filtering means. Next, executing means will carry out execution of the order and reporting means will report the result of the order execution to the client. A method for automatically executing a securities trade according to the present invention includes the steps of first creating at least one filter and then entering an order for a security by a client. Next, each filter is applied to the order to determine whether the order can be automatically executed. The order is then routed to a destination based upon whether the order can be automatically executed. The order will be executed and the results of the trade are reported to the client. BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention, reference is made to the following detailed description of an exemplary embodiment considered in conjunction with the accompanying drawings, in which: FIG. 1 is a diagrammatical overview of the system of the present invention; FIG. 2 is a rule definition screen used in connection with the system shown in FIG. 1 ; FIG. 3 is a rule summary screen used in connection with the system shown in FIG. 1 ; FIG. 4 is an alert definition screen used in connection with the system shown in FIG. 1 ; FIG. 5 is an alert summary screen used in connection with the system shown in FIG. 1 ; FIG. 6 is a broker alert definition screen used in connection with the system shown in FIG. 1 ; and FIG. 7 is a broker alert summary screen used in connection with the system shown in FIG. 1 . DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a diagrammatic overview of an automated trade execution system 10 constructed in accordance with the present invention. A client 12 places an order 14 via an order management system 16 . The order 14 enters a brokerage's internal systems 18 via a firewall 20 . The firewall 20 provides the usual types of protection expected when using a firewall, such as protection of the brokerage's internal systems 18 and client validation, to ensure that only authorized clients 12 can access the brokerage's internal systems 18 . To protect the client 12 and the security of an order 14 , an order is encrypted by the order management system 16 before being sent through the firewall 20 . The order management system 16 can be of any type desired by the client 12 , provided that the order management system 16 can communicate with the brokerage's internal systems 18 . The order management system 16 can operate on an unillustrated communications device such as a conventional personal computer or a wireless access device such as a personal digital assistant, and over a suitable communications network to access the brokerage's internal systems 18 . By way of illustration but not limitation, when communicating with a particular brokerage, the order management system 16 may need to be capable of sending a FIX protocol message to the brokerage's internal systems 18 . FIX or Financial Information Exchange protocol is a messaging standard developed specifically for the real-time electronic exchange of securities transactions and is a public-domain specification owned and maintained by FIX Protocol, Ltd. It will be understood that different message protocols may be required to enable communication between the order management system 16 and other brokerages. In a fully automated embodiment, the trade execution system 10 is preferably configured with appropriate proprietary or commercially available software suitable to enable direct interaction with a client 12 . Preferably, the system 10 is highly scalable, whereby any number of clients may be readily connected to and simultaneously submit orders to the system. Further, the system architecture may be portable and capable of being run on a variety of software platforms such as Windows®, UNIX®, etc. The system 10 may comprise a flexible and adaptable client-server architecture that employs any suitable object-oriented programming language such as, for example, Java® or C++. The system 10 may also operate on any electronic communication network capable of enabling interactive participation by users of the system. Examples of communication networks that may support the system 10 include the Internet, a proprietary network, a local or wide area network, a wireless network, a telephone network, etc. By way of illustration but not limitation, the system 10 may be a World Wide Web (Web) based system functioning on the Internet. The system 10 further includes a communication network services integrator appropriate for the communication network within which the system is implemented. For example, in a Web based environment, a suitable communication network services integrator may be the user interface, program logic, data server, and Web server applications marketed by Oracle Corp. of Redwood Shores, Calif. The order 14 first passes through a series of broker filters 22 , which evaluate items such as a credit check on the client 12 to determine whether the order 14 can be covered, whether the order 14 is for a restricted security, or whether the order 14 has exceeded any limits placed on the client's account. The types of checks applied by the broker filters 22 can include any check to validate whether an order 14 can be processed. If the order 14 does not clear all of the broker filters 22 , an exception 24 is generated which is passed, along with the order 14 , to a broker 26 . The broker 26 will then contact the client 12 regarding the exceptions 24 to attempt to resolve the problem. Once the order 14 has been rejected, the client 12 may resubmit the order 14 by re-entering it in the same way as the original order. However, if the order 14 has been rejected on, for example, credit grounds, then it is unlikely to succeed until the credit limit has been altered (e.g., raised) or otherwise addressed. The broker filters 22 are pre-defined by the rules of the brokerage and cannot be modified by the client 12 . Other types of broker filters 22 can include whether the order 14 is a standard market order or a limit order, whether the execution instructions on the order 14 are “held” (meaning that the trader has no discretion in filling the order) or “not held” (meaning that the trader can exercise discretion in filling the order; this is the default setting when used), whether the order 14 is for regular settlement in the normal trading currency, and whether there are any special instructions associated with the order 14 . If the order 14 clears all of the broker filters 22 , it is passed to a series of trader filters 30 which will determine whether the order 14 is automatically processed, whether a trader 32 will need to manually fill the order 14 , or whether the trader 32 will need to manually send the order 14 to an exchange. The trader filters 30 include the types of checks a trader 32 would use in evaluating an order 14 and deciding the best method of filling the order 14 . For example, the trader filters 30 can include items such as volume of the order 14 in terms of the number of shares involved, the value of the order 14 , any limit price on the order 14 , and the current price spread of the product. The trader filters 30 will be discussed in greater detail below in connection with FIG. 2 . If an order 14 does not clear any one of the trader filters 30 , it will be passed to a trader 32 to be manually processed. The trader filters 30 may be individually active or inactive, but an order 14 must pass through all of the active trader filters 30 to be automatically processed. The number of orders 14 that will be manually handled by the trader 32 is dependent upon the number of trader filters 30 that are set, the criteria of each of the trader filters 30 , and the types of orders that the trader 32 normally receives. Each trader 32 has the ability to set the criteria for his or her own trader filters 30 , as will be discussed below in connection with FIG. 2 . Ideally, the trader filters 30 will accept smaller orders 14 (in terms of both volume and value) and will only pass larger or unusual orders 14 to the trader 32 for manual processing. If an order 14 meets the requirements of all of the trader filters 30 , it will be passed to a set of compliance filters 40 . The compliance filters 40 are used to determine if the order 14 can be filled based upon the governing market rules. For example, a determination is made whether the order 14 is of a minimum volume (i.e., no odd-lot trades), whether the price of the order 14 is within a specified percentage of the market price, or whether the security is presently suspended from trading. Additional compliance filters 40 can be added when necessary to meet specific compliance concerns. The compliance filters 40 are dictated by the local market rules, and cannot be modified by either the brokers 26 or the traders 32 . If the order 14 fails any of the compliance filters 40 , an exception 42 will be generated, and the order 14 along with the exception 42 will be passed to the trader 32 for manual processing. A human compliance officer 44 can view the compliance filters 40 in operation, to determine what number of orders 14 meet or fail the criteria set. If the order 14 passes all of the compliance filters 40 , and depending on the action status of the relevant rule, it will be forwarded to be automatically filled from inventory 50 of the brokerage or directed to an appropriate trading exchange 52 . At present, it is believed that only human compliance officers are able to monitor the compliance filters 40 . However, at such time that automated/electronic transaction compliance technology is developed that partially or completely performs the functions of a human compliance officer, it will be understood that such technology may be used in the automated trade execution system 10 of the present invention. To be able to properly track an order 14 as it moves through the brokerage's internal systems 18 , certain identifying information is attached to the data record that includes the order 14 , such as client and account identifiers and tags. A tag is used to uniquely identify every trade or execution that is processed by the system 10 . With this additional information, an audit trail for the order 14 can be constructed so that the progress of the order 14 through the various filters 22 , 30 , 40 can be monitored. The compliance officer 44 can view the audit trail at any time, to monitor order flow and to ensure that an order 14 is being properly handled. Presently, the compliance officer 44 can call a member of the relevant team for a detailed description of an identified problem, although a brief description can be obtained from the order history and the associated tags. The background process is also responsible for accepting orders via FIX, handing off the orders to the automated trade execution system 10 , and if necessary, routing orders to the applicable exchange or filling the orders from inventory. After an order 14 is processed either from inventory 50 or through an exchange 52 , a status record 60 is generated. The status record 60 is passed backwards through the brokerage's internal systems 18 until the status record 60 is passed through the firewall 20 where it can be retrieved by the order management system 16 . This way, the client 12 has a complete record of the history of the order 14 and whether the order 14 was successfully filled. FIG. 2 is a rule definition screen 200 that is used by a trader 32 to define the trader filters 30 . (The terms “filter” and “rule” are used interchangeably herein.) A rule 202 is the collection of information that is used to check against an order. A Product 204 is the security that the rule 202 is to be defined for on a particular Market 206 . A Priority 208 is assigned to the rule 202 which determines the order in which the rule 202 is applied to the Product 204 . If there are multiple rules 202 defined for a Product 204 , each rule 202 will have a different Priority 208 and will be tested against the order by ascending priority value. The checkboxes 210 , 212 , 214 , 216 can be used to determine whether the system 10 should test an order 14 against an Individual Client 210 or a Client Group 212 and/or against a Booking Representative 214 or a Booking Representative Group 216 . The grouping of the checkboxes is such that either both the Individual Client 210 and the Client Group 212 are unchecked or only one of them is checked. The same grouping principle applies to the Booking Representative 214 and the Booking Representative Group 216 . When the desired Client and/or Booking Representative selection(s) have been made in checkboxes 210 , 212 , 214 , 216 , appropriate dropdown lists appear which are populated with the relevant options for the selected checkbox(es) from which the user chooses the desired Individual Client 210 or Client Group 212 and/or Booking Representative 214 or Booking Representative Group 216 . The value for Side 220 allows the trader to determine what type of transactions will be filtered by the rule 202 . The Side 220 may be “buy” for buy orders, “sell” for sell orders, or “all” for both buy and sell orders. The Volume 222 is based on the number of shares for a single order. At 224 , the value of the order to be filtered can be expressed in United States dollars or, at 226 , the local currency. Limit 228 is the limit price on a limit order that can pass the rule 202 . A limit order is an order to a broker to buy a specified quantity of a security at or below a specified price, or to sell it at or above a specified price. The Spread Ticks value 230 is used to determine whether the order price is within the specified value of the current market price for the Product 204 . The value specified for Spread Ticks is the difference between the bid and the offer. The spread is the current market spread, so that specifying a rule with a spread less than or equal to five (for example), would mean that the order would only be automatically traded if the current bid-offer spread was less than five ticks. The trader may want to limit orders to be automatically processed only when the volatility of the stock is low, i.e., with a small spread. The values for Volume 222 , Value 224 , Value 226 , Limit 228 , and Spread Ticks 230 may be defined to be either less than, less than/equal to, greater than, or greater than/equal to (via the drop-down list) the numeric value entered into the field. The selections for Action 232 determine where an order is sent after it successfully passes the applicable rule 202 . The possible values for Action 232 include: “Send To Exchange,” where the order will be sent directly to the exchange where the Product 204 is traded; “Fill From Inventory,” where the order will be filled from the inventory of the brokerage; and “Send Round Lot, Fill Odd Lot,” which is used on exchanges that prohibit orders having a volume that is not equal to a multiple of a given lot size, where the round lot portion will be sent to the exchange and the odd lot portion will be filled from the inventory of the brokerage. The value for Send To 234 directs where the order should be sent if it passes all of the specified criteria. If the Action 232 is “Send To Exchange,” then Send To 234 will be a code for the exchange. Send To 234 is not specified for the action “Fill From Inventory”. The Firm Account 236 is used when the Action 232 is “Send To Exchange” to properly track the order and credit or debit the appropriate account. The firm account is a tool that enables the company to track its position. Quantities of (positions in) related stocks are usually tracked in the same account. The From time 238 and the To time 240 are used to set the boundaries for when the rule is operational. Since the system 10 is designed to process orders automatically, it is necessary for the Market 206 where the Product 204 is traded to be open for business. The Is Active checkbox 242 is used to place a rule 202 into and out of an active state. The checkbox 242 can be used to disable a particular rule 202 without having to delete it from the system. When defining the criteria that comprise a rule 202 , a trader can select any combination of criteria; it is not necessary to define values for all of the criteria. For an order to successfully pass a given rule 202 , all of the specified criteria need to be satisfied. If the order does not pass one of the criteria of the rule 202 , the order fails the rule 202 and will then be passed to a trader 32 for manual processing. After the criteria for the rule 202 have been defined, the user can save or delete the rule 202 by clicking on the appropriate button 250 , 252 . Additional filters can be added and can include any quantifiable criteria that a trader would normally evaluate in determining how to process an order. Furthermore, a trader may set limits for the total volume or total value of orders that may be executed against the brokerage's inventory or directed to an exchange. Referring now to FIG. 3 , a rule summary screen 300 contains a compact listing of all of the rules 202 that have been defined in the system 10 . A rule summary 302 includes the market 304 for which the rule 202 applies and the criteria 306 for each product 308 . An individual rule 202 may enabled (e.g., made active or inactive) by toggling the checkbox 310 . A user can view the details of a rule 202 by clicking on the Details link 312 , which will lead the user to a screen like that shown in FIG. 2 . A default trader dropdown list (Trader list) 320 identifies those persons with permissions to execute (i.e., trade) on the respective exchanges. Persons on Trader list 320 can view and edit rules 202 . The dropdown list contains all valid traders for the relevant market. A selected trader on Trader list 320 is a person to whom certain orders that do not meet the criteria 306 of a rule 202 will be sent. A rejected order will be sent to all relevant traders for that market, not just the trader selected in the Trader list 320 . Persons on Trader list 320 each have a unique trader identifier that is associated with an order that is sent to an exchange. In effect, the automated process of the present invention thus works “on behalf” of the trader. By clicking on the Update button 322 , the user saves a changed value of a trader specified in Trader list 320 . FIG. 4 shows an alert definition screen 400 that permits a user to define when an alert 402 is generated. An alert 402 will notify a trader when a certain condition occurs, as will be explained below. An alert 402 can be defined for a specific Product 404 traded on a Market 406 and by the type of Action 408 to be performed as defined by the rule for that Product 404 . Additionally, an alert be created for all products in a market. The Type 410 can include United States dollar value, local currency value, or volume of the order. The Value 412 is a check against which it will be determined whether to trigger an alert. The Alert Level 414 is a percentage value which is used to determine when an alert 402 will be generated, which is when the value in the order specified by the selection of the Type 410 is greater than the Value 412 multiplied by the Alert Level 414 . The Alert Only checkbox 416 is used to determine what type of alert will be sent to the trader. If the box 416 is checked, only an alert will be sent to the trader. If the box 416 is not checked, the system 10 will stop processing the rule that allowed the order that violated the threshold to be automatically traded (i.e., the offending rule will be made inactive). The Is Active checkbox 418 permits the user to selectively activate the alert 402 without having to delete it from the system 10 . Once the user has defined the alert 402 , the user can either save or delete the alert 402 by clicking the appropriate buttons 420 , 422 . FIG. 5 shows an alert summary screen 500 that displays an alert summary 502 for each alert 402 that has been created by the user. The alert summary 502 is grouped by market 504 and lists the criteria 506 that have been defined for either a particular product 508 or an entire market 504 . An Enabled checkbox 510 permits the user to active or deactivate an alert 402 without having to delete the alert 402 from the system 10 . The user can also view the details of the alert 402 by clicking on the Details link 512 . The Enabled checkboxes 510 associated with each alert summary 502 allow the user to configure a variety of alerts 402 . The user can enable all of the alerts 402 by clicking the Select All button 520 or deactivate all of the alerts 402 by clicking on the Clear Selection button 522 . Once the user has enabled their desired selection of alerts 402 , clicking on the Activate Current Selection button 524 will activate all of the alerts 402 that have been enabled. FIG. 6 shows a broker alert definition screen 600 that permits a user to define when a broker alert 602 is generated. A broker alert 602 will notify a trader when the thresholds for a given broker have been met or exceeded. This allows the trader to be alerted when a certain amount of business has been done through a given broker. An alert 602 is defined for a specific broker (Send To) 604 . The Type 606 can include United States dollar value, local currency value, or volume of the order. The Value 606 is the numerical value that will be tested in order to generate the alert 602 . The Alert Level 610 is a percentage value used to determine when the threshold has been exceeded. An alert 602 will be generated when the total value of all the orders generated by the broker 604 specified by the selection of the Type 606 is greater than the Value 608 multiplied by the Alert Level 610 . The Is Active checkbox 612 permits the user to selectively activate the alert 602 without having to delete it from the system 10 . Once the user has defined the alert 602 , the user can either save or delete the alert 602 by clicking the appropriate buttons 620 , 622 . FIG. 7 shows a broker alert summary screen 700 that displays an alert summary 702 for each alert 602 that has been created by the user. The alert summary 702 is grouped by broker 704 and lists the criteria 706 that have been defined for the broker 704 and the Type of alert 708 desired. An Enabled checkbox 710 permits the user to active or deactivate a broker alert 602 without having to delete the alert 602 from the system 10 . The user can also view the details of the alert 602 by clicking on the Details link 712 . The Enabled checkboxes 710 associated with each alert summary 702 allow the user to configure a variety of alerts 602 . The user can enable all of the broker alerts 602 by clicking the Select All button 720 or deactivate all of the alerts 602 by clicking on the Clear Selection button 722 . Once the user has enabled their desired selection of broker alerts 602 , clicking on the Activate Current Selection button 724 will activate all of the alerts 602 that have been enabled. It will be understood that the embodiment described herein is merely exemplary and that a person skilled in the art may make many variations and modifications without departing from the spirit and scope of the present invention. For instance, the filters exemplified herein can be expanded to include any type of filter that would accomplish the goal to be achieved by that stage of the processing. Moreover, the user screens shown in FIGS. 2-7 are illustrative of a preferred embodiment for constructing the filters and communicating this information to a user of the system 10 . A person skilled in the art would be readily able to create many other types of user screens that would collect and display the necessary information contained therein. In addition, the criteria defined for a filter can be any quantifiable criteria that would normally be evaluated by a trader when processing an order. All such variations and modifications are intended to be included within the scope of the invention as defined in the appended claims.
An automated securities order execution system includes order entering means for a client to enter an order and at least one filtering means for determining whether the order can be automatically executed. Routing means are used for routing the order to a destination based upon the determination made by each of the filtering means. After the order has been properly routed, the order is executed and the result of the order execution is reported to the client.
Briefly outline the background technology and the problem the invention aims to solve.
[ "FIELD OF THE INVENTION The present invention relates to a system and method for automatically executing securities trades based upon a series of user-definable rules.", "BACKGROUND OF THE INVENTION Under existing equities trading systems, a trader needs to review every order, including small orders, and make a decision as to whether to send the order to an exchange or to fill the order from the inventory of the brokerage.", "For certain orders, for example where the client has asked for a limit order, the trader would need to review the order and perform an action on it.", "While this arrangement provides for accurate order placement, it lengthens the time between when the order is placed and when the order is filled due to the review process undertaken by the trader.", "In an environment where market movements may be large and rapid, short execution times are critical in obtaining the best possible price for a trade.", "Combine the rapidly-moving markets with computer-enabled order placement, and customers desire (and often expect) to have their orders executed as soon as possible after being placed.", "By requiring the trader to manually review each order and make a decision thereon, the execution time of the order is inherently slow.", "It is therefore desirable to shorten the time between when an order is placed and when the order is executed.", "The system and method of the present invention are designed to overcome the limitations in the prior art.", "SUMMARY OF THE INVENTION By using the system and method of the present invention, a trader can set some basic rules for all orders, so that the trader does not need to take any action on an order if it meets the pre-defined criteria.", "If the order fails to meet the criteria, then the trader will directly act upon the order;", "otherwise, all orders will be automatically processed which will shorten execution time.", "The system is most effective with small orders which are easily filled.", "By freeing up some of the trader's time, he or she can concentrate on the larger orders that are more difficult to fill.", "An order that is entered into the system of the present invention can be handled in one of three ways: (1) worked by the trader in the same manner as a typical telephone order;", "(2) automatically filled from the brokerage's inventory;", "or (3) automatically forwarded to a trading exchange to be filled.", "An order will be automatically processed only if certain pre-defined criteria are met.", "This is accomplished by passing an order through a series of filters;", "if the order passes through all the filters, then it will be automatically processed.", "If an order does not meet all of the filters, it will be passed out of the filter loop to a trader to be manually processed.", "An automated securities order execution system according to the present invention includes order entering means for a client to enter an order and at least one filtering means for determining whether the order can be automatically executed.", "After the filtering means have been applied, routing means will route the order to a destination based upon the determination made by the filtering means.", "Next, executing means will carry out execution of the order and reporting means will report the result of the order execution to the client.", "A method for automatically executing a securities trade according to the present invention includes the steps of first creating at least one filter and then entering an order for a security by a client.", "Next, each filter is applied to the order to determine whether the order can be automatically executed.", "The order is then routed to a destination based upon whether the order can be automatically executed.", "The order will be executed and the results of the trade are reported to the client.", "BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention, reference is made to the following detailed description of an exemplary embodiment considered in conjunction with the accompanying drawings, in which: FIG. 1 is a diagrammatical overview of the system of the present invention;", "FIG. 2 is a rule definition screen used in connection with the system shown in FIG. 1 ;", "FIG. 3 is a rule summary screen used in connection with the system shown in FIG. 1 ;", "FIG. 4 is an alert definition screen used in connection with the system shown in FIG. 1 ;", "FIG. 5 is an alert summary screen used in connection with the system shown in FIG. 1 ;", "FIG. 6 is a broker alert definition screen used in connection with the system shown in FIG. 1 ;", "and FIG. 7 is a broker alert summary screen used in connection with the system shown in FIG. 1 .", "DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a diagrammatic overview of an automated trade execution system 10 constructed in accordance with the present invention.", "A client 12 places an order 14 via an order management system 16 .", "The order 14 enters a brokerage's internal systems 18 via a firewall 20 .", "The firewall 20 provides the usual types of protection expected when using a firewall, such as protection of the brokerage's internal systems 18 and client validation, to ensure that only authorized clients 12 can access the brokerage's internal systems 18 .", "To protect the client 12 and the security of an order 14 , an order is encrypted by the order management system 16 before being sent through the firewall 20 .", "The order management system 16 can be of any type desired by the client 12 , provided that the order management system 16 can communicate with the brokerage's internal systems 18 .", "The order management system 16 can operate on an unillustrated communications device such as a conventional personal computer or a wireless access device such as a personal digital assistant, and over a suitable communications network to access the brokerage's internal systems 18 .", "By way of illustration but not limitation, when communicating with a particular brokerage, the order management system 16 may need to be capable of sending a FIX protocol message to the brokerage's internal systems 18 .", "FIX or Financial Information Exchange protocol is a messaging standard developed specifically for the real-time electronic exchange of securities transactions and is a public-domain specification owned and maintained by FIX Protocol, Ltd", "It will be understood that different message protocols may be required to enable communication between the order management system 16 and other brokerages.", "In a fully automated embodiment, the trade execution system 10 is preferably configured with appropriate proprietary or commercially available software suitable to enable direct interaction with a client 12 .", "Preferably, the system 10 is highly scalable, whereby any number of clients may be readily connected to and simultaneously submit orders to the system.", "Further, the system architecture may be portable and capable of being run on a variety of software platforms such as Windows®, UNIX®, etc.", "The system 10 may comprise a flexible and adaptable client-server architecture that employs any suitable object-oriented programming language such as, for example, Java® or C++.", "The system 10 may also operate on any electronic communication network capable of enabling interactive participation by users of the system.", "Examples of communication networks that may support the system 10 include the Internet, a proprietary network, a local or wide area network, a wireless network, a telephone network, etc.", "By way of illustration but not limitation, the system 10 may be a World Wide Web (Web) based system functioning on the Internet.", "The system 10 further includes a communication network services integrator appropriate for the communication network within which the system is implemented.", "For example, in a Web based environment, a suitable communication network services integrator may be the user interface, program logic, data server, and Web server applications marketed by Oracle Corp.", "of Redwood Shores, Calif.", "The order 14 first passes through a series of broker filters 22 , which evaluate items such as a credit check on the client 12 to determine whether the order 14 can be covered, whether the order 14 is for a restricted security, or whether the order 14 has exceeded any limits placed on the client's account.", "The types of checks applied by the broker filters 22 can include any check to validate whether an order 14 can be processed.", "If the order 14 does not clear all of the broker filters 22 , an exception 24 is generated which is passed, along with the order 14 , to a broker 26 .", "The broker 26 will then contact the client 12 regarding the exceptions 24 to attempt to resolve the problem.", "Once the order 14 has been rejected, the client 12 may resubmit the order 14 by re-entering it in the same way as the original order.", "However, if the order 14 has been rejected on, for example, credit grounds, then it is unlikely to succeed until the credit limit has been altered (e.g., raised) or otherwise addressed.", "The broker filters 22 are pre-defined by the rules of the brokerage and cannot be modified by the client 12 .", "Other types of broker filters 22 can include whether the order 14 is a standard market order or a limit order, whether the execution instructions on the order 14 are “held”", "(meaning that the trader has no discretion in filling the order) or “not held”", "(meaning that the trader can exercise discretion in filling the order;", "this is the default setting when used), whether the order 14 is for regular settlement in the normal trading currency, and whether there are any special instructions associated with the order 14 .", "If the order 14 clears all of the broker filters 22 , it is passed to a series of trader filters 30 which will determine whether the order 14 is automatically processed, whether a trader 32 will need to manually fill the order 14 , or whether the trader 32 will need to manually send the order 14 to an exchange.", "The trader filters 30 include the types of checks a trader 32 would use in evaluating an order 14 and deciding the best method of filling the order 14 .", "For example, the trader filters 30 can include items such as volume of the order 14 in terms of the number of shares involved, the value of the order 14 , any limit price on the order 14 , and the current price spread of the product.", "The trader filters 30 will be discussed in greater detail below in connection with FIG. 2 .", "If an order 14 does not clear any one of the trader filters 30 , it will be passed to a trader 32 to be manually processed.", "The trader filters 30 may be individually active or inactive, but an order 14 must pass through all of the active trader filters 30 to be automatically processed.", "The number of orders 14 that will be manually handled by the trader 32 is dependent upon the number of trader filters 30 that are set, the criteria of each of the trader filters 30 , and the types of orders that the trader 32 normally receives.", "Each trader 32 has the ability to set the criteria for his or her own trader filters 30 , as will be discussed below in connection with FIG. 2 .", "Ideally, the trader filters 30 will accept smaller orders 14 (in terms of both volume and value) and will only pass larger or unusual orders 14 to the trader 32 for manual processing.", "If an order 14 meets the requirements of all of the trader filters 30 , it will be passed to a set of compliance filters 40 .", "The compliance filters 40 are used to determine if the order 14 can be filled based upon the governing market rules.", "For example, a determination is made whether the order 14 is of a minimum volume (i.e., no odd-lot trades), whether the price of the order 14 is within a specified percentage of the market price, or whether the security is presently suspended from trading.", "Additional compliance filters 40 can be added when necessary to meet specific compliance concerns.", "The compliance filters 40 are dictated by the local market rules, and cannot be modified by either the brokers 26 or the traders 32 .", "If the order 14 fails any of the compliance filters 40 , an exception 42 will be generated, and the order 14 along with the exception 42 will be passed to the trader 32 for manual processing.", "A human compliance officer 44 can view the compliance filters 40 in operation, to determine what number of orders 14 meet or fail the criteria set.", "If the order 14 passes all of the compliance filters 40 , and depending on the action status of the relevant rule, it will be forwarded to be automatically filled from inventory 50 of the brokerage or directed to an appropriate trading exchange 52 .", "At present, it is believed that only human compliance officers are able to monitor the compliance filters 40 .", "However, at such time that automated/electronic transaction compliance technology is developed that partially or completely performs the functions of a human compliance officer, it will be understood that such technology may be used in the automated trade execution system 10 of the present invention.", "To be able to properly track an order 14 as it moves through the brokerage's internal systems 18 , certain identifying information is attached to the data record that includes the order 14 , such as client and account identifiers and tags.", "A tag is used to uniquely identify every trade or execution that is processed by the system 10 .", "With this additional information, an audit trail for the order 14 can be constructed so that the progress of the order 14 through the various filters 22 , 30 , 40 can be monitored.", "The compliance officer 44 can view the audit trail at any time, to monitor order flow and to ensure that an order 14 is being properly handled.", "Presently, the compliance officer 44 can call a member of the relevant team for a detailed description of an identified problem, although a brief description can be obtained from the order history and the associated tags.", "The background process is also responsible for accepting orders via FIX, handing off the orders to the automated trade execution system 10 , and if necessary, routing orders to the applicable exchange or filling the orders from inventory.", "After an order 14 is processed either from inventory 50 or through an exchange 52 , a status record 60 is generated.", "The status record 60 is passed backwards through the brokerage's internal systems 18 until the status record 60 is passed through the firewall 20 where it can be retrieved by the order management system 16 .", "This way, the client 12 has a complete record of the history of the order 14 and whether the order 14 was successfully filled.", "FIG. 2 is a rule definition screen 200 that is used by a trader 32 to define the trader filters 30 .", "(The terms “filter”", "and “rule”", "are used interchangeably herein.) A rule 202 is the collection of information that is used to check against an order.", "A Product 204 is the security that the rule 202 is to be defined for on a particular Market 206 .", "A Priority 208 is assigned to the rule 202 which determines the order in which the rule 202 is applied to the Product 204 .", "If there are multiple rules 202 defined for a Product 204 , each rule 202 will have a different Priority 208 and will be tested against the order by ascending priority value.", "The checkboxes 210 , 212 , 214 , 216 can be used to determine whether the system 10 should test an order 14 against an Individual Client 210 or a Client Group 212 and/or against a Booking Representative 214 or a Booking Representative Group 216 .", "The grouping of the checkboxes is such that either both the Individual Client 210 and the Client Group 212 are unchecked or only one of them is checked.", "The same grouping principle applies to the Booking Representative 214 and the Booking Representative Group 216 .", "When the desired Client and/or Booking Representative selection(s) have been made in checkboxes 210 , 212 , 214 , 216 , appropriate dropdown lists appear which are populated with the relevant options for the selected checkbox(es) from which the user chooses the desired Individual Client 210 or Client Group 212 and/or Booking Representative 214 or Booking Representative Group 216 .", "The value for Side 220 allows the trader to determine what type of transactions will be filtered by the rule 202 .", "The Side 220 may be “buy”", "for buy orders, “sell”", "for sell orders, or “all”", "for both buy and sell orders.", "The Volume 222 is based on the number of shares for a single order.", "At 224 , the value of the order to be filtered can be expressed in United States dollars or, at 226 , the local currency.", "Limit 228 is the limit price on a limit order that can pass the rule 202 .", "A limit order is an order to a broker to buy a specified quantity of a security at or below a specified price, or to sell it at or above a specified price.", "The Spread Ticks value 230 is used to determine whether the order price is within the specified value of the current market price for the Product 204 .", "The value specified for Spread Ticks is the difference between the bid and the offer.", "The spread is the current market spread, so that specifying a rule with a spread less than or equal to five (for example), would mean that the order would only be automatically traded if the current bid-offer spread was less than five ticks.", "The trader may want to limit orders to be automatically processed only when the volatility of the stock is low, i.e., with a small spread.", "The values for Volume 222 , Value 224 , Value 226 , Limit 228 , and Spread Ticks 230 may be defined to be either less than, less than/equal to, greater than, or greater than/equal to (via the drop-down list) the numeric value entered into the field.", "The selections for Action 232 determine where an order is sent after it successfully passes the applicable rule 202 .", "The possible values for Action 232 include: “Send To Exchange,” where the order will be sent directly to the exchange where the Product 204 is traded;", "“Fill From Inventory,” where the order will be filled from the inventory of the brokerage;", "and “Send Round Lot, Fill Odd Lot,” which is used on exchanges that prohibit orders having a volume that is not equal to a multiple of a given lot size, where the round lot portion will be sent to the exchange and the odd lot portion will be filled from the inventory of the brokerage.", "The value for Send To 234 directs where the order should be sent if it passes all of the specified criteria.", "If the Action 232 is “Send To Exchange,” then Send To 234 will be a code for the exchange.", "Send To 234 is not specified for the action “Fill From Inventory.”", "The Firm Account 236 is used when the Action 232 is “Send To Exchange”", "to properly track the order and credit or debit the appropriate account.", "The firm account is a tool that enables the company to track its position.", "Quantities of (positions in) related stocks are usually tracked in the same account.", "The From time 238 and the To time 240 are used to set the boundaries for when the rule is operational.", "Since the system 10 is designed to process orders automatically, it is necessary for the Market 206 where the Product 204 is traded to be open for business.", "The Is Active checkbox 242 is used to place a rule 202 into and out of an active state.", "The checkbox 242 can be used to disable a particular rule 202 without having to delete it from the system.", "When defining the criteria that comprise a rule 202 , a trader can select any combination of criteria;", "it is not necessary to define values for all of the criteria.", "For an order to successfully pass a given rule 202 , all of the specified criteria need to be satisfied.", "If the order does not pass one of the criteria of the rule 202 , the order fails the rule 202 and will then be passed to a trader 32 for manual processing.", "After the criteria for the rule 202 have been defined, the user can save or delete the rule 202 by clicking on the appropriate button 250 , 252 .", "Additional filters can be added and can include any quantifiable criteria that a trader would normally evaluate in determining how to process an order.", "Furthermore, a trader may set limits for the total volume or total value of orders that may be executed against the brokerage's inventory or directed to an exchange.", "Referring now to FIG. 3 , a rule summary screen 300 contains a compact listing of all of the rules 202 that have been defined in the system 10 .", "A rule summary 302 includes the market 304 for which the rule 202 applies and the criteria 306 for each product 308 .", "An individual rule 202 may enabled (e.g., made active or inactive) by toggling the checkbox 310 .", "A user can view the details of a rule 202 by clicking on the Details link 312 , which will lead the user to a screen like that shown in FIG. 2 .", "A default trader dropdown list (Trader list) 320 identifies those persons with permissions to execute (i.e., trade) on the respective exchanges.", "Persons on Trader list 320 can view and edit rules 202 .", "The dropdown list contains all valid traders for the relevant market.", "A selected trader on Trader list 320 is a person to whom certain orders that do not meet the criteria 306 of a rule 202 will be sent.", "A rejected order will be sent to all relevant traders for that market, not just the trader selected in the Trader list 320 .", "Persons on Trader list 320 each have a unique trader identifier that is associated with an order that is sent to an exchange.", "In effect, the automated process of the present invention thus works “on behalf”", "of the trader.", "By clicking on the Update button 322 , the user saves a changed value of a trader specified in Trader list 320 .", "FIG. 4 shows an alert definition screen 400 that permits a user to define when an alert 402 is generated.", "An alert 402 will notify a trader when a certain condition occurs, as will be explained below.", "An alert 402 can be defined for a specific Product 404 traded on a Market 406 and by the type of Action 408 to be performed as defined by the rule for that Product 404 .", "Additionally, an alert be created for all products in a market.", "The Type 410 can include United States dollar value, local currency value, or volume of the order.", "The Value 412 is a check against which it will be determined whether to trigger an alert.", "The Alert Level 414 is a percentage value which is used to determine when an alert 402 will be generated, which is when the value in the order specified by the selection of the Type 410 is greater than the Value 412 multiplied by the Alert Level 414 .", "The Alert Only checkbox 416 is used to determine what type of alert will be sent to the trader.", "If the box 416 is checked, only an alert will be sent to the trader.", "If the box 416 is not checked, the system 10 will stop processing the rule that allowed the order that violated the threshold to be automatically traded (i.e., the offending rule will be made inactive).", "The Is Active checkbox 418 permits the user to selectively activate the alert 402 without having to delete it from the system 10 .", "Once the user has defined the alert 402 , the user can either save or delete the alert 402 by clicking the appropriate buttons 420 , 422 .", "FIG. 5 shows an alert summary screen 500 that displays an alert summary 502 for each alert 402 that has been created by the user.", "The alert summary 502 is grouped by market 504 and lists the criteria 506 that have been defined for either a particular product 508 or an entire market 504 .", "An Enabled checkbox 510 permits the user to active or deactivate an alert 402 without having to delete the alert 402 from the system 10 .", "The user can also view the details of the alert 402 by clicking on the Details link 512 .", "The Enabled checkboxes 510 associated with each alert summary 502 allow the user to configure a variety of alerts 402 .", "The user can enable all of the alerts 402 by clicking the Select All button 520 or deactivate all of the alerts 402 by clicking on the Clear Selection button 522 .", "Once the user has enabled their desired selection of alerts 402 , clicking on the Activate Current Selection button 524 will activate all of the alerts 402 that have been enabled.", "FIG. 6 shows a broker alert definition screen 600 that permits a user to define when a broker alert 602 is generated.", "A broker alert 602 will notify a trader when the thresholds for a given broker have been met or exceeded.", "This allows the trader to be alerted when a certain amount of business has been done through a given broker.", "An alert 602 is defined for a specific broker (Send To) 604 .", "The Type 606 can include United States dollar value, local currency value, or volume of the order.", "The Value 606 is the numerical value that will be tested in order to generate the alert 602 .", "The Alert Level 610 is a percentage value used to determine when the threshold has been exceeded.", "An alert 602 will be generated when the total value of all the orders generated by the broker 604 specified by the selection of the Type 606 is greater than the Value 608 multiplied by the Alert Level 610 .", "The Is Active checkbox 612 permits the user to selectively activate the alert 602 without having to delete it from the system 10 .", "Once the user has defined the alert 602 , the user can either save or delete the alert 602 by clicking the appropriate buttons 620 , 622 .", "FIG. 7 shows a broker alert summary screen 700 that displays an alert summary 702 for each alert 602 that has been created by the user.", "The alert summary 702 is grouped by broker 704 and lists the criteria 706 that have been defined for the broker 704 and the Type of alert 708 desired.", "An Enabled checkbox 710 permits the user to active or deactivate a broker alert 602 without having to delete the alert 602 from the system 10 .", "The user can also view the details of the alert 602 by clicking on the Details link 712 .", "The Enabled checkboxes 710 associated with each alert summary 702 allow the user to configure a variety of alerts 602 .", "The user can enable all of the broker alerts 602 by clicking the Select All button 720 or deactivate all of the alerts 602 by clicking on the Clear Selection button 722 .", "Once the user has enabled their desired selection of broker alerts 602 , clicking on the Activate Current Selection button 724 will activate all of the alerts 602 that have been enabled.", "It will be understood that the embodiment described herein is merely exemplary and that a person skilled in the art may make many variations and modifications without departing from the spirit and scope of the present invention.", "For instance, the filters exemplified herein can be expanded to include any type of filter that would accomplish the goal to be achieved by that stage of the processing.", "Moreover, the user screens shown in FIGS. 2-7 are illustrative of a preferred embodiment for constructing the filters and communicating this information to a user of the system 10 .", "A person skilled in the art would be readily able to create many other types of user screens that would collect and display the necessary information contained therein.", "In addition, the criteria defined for a filter can be any quantifiable criteria that would normally be evaluated by a trader when processing an order.", "All such variations and modifications are intended to be included within the scope of the invention as defined in the appended claims." ]
TECHNICAL FIELD OF THE INVENTION The present invention relates generally to downhole tools for determining characteristics of the borehole and formation during or after the drilling of a well. More particularly, the present invention relates to a resistivity logging tool for measuring formation resistivity parameters. Still more particularly, the present invention relates to a method for processing resistivity measurement variables to improve the detection of bed boundaries. BACKGROUND OF THE INVENTION Modern petroleum drilling and production operations demand a great quantity of information relating to parameters and conditions downhole. Such information typically includes characteristics of the earth formations traversed by the wellbore, in addition to data relating to the size and configuration of the borehole itself. The collection of information relating to conditions downhole, which commonly is referred to as “logging,” can be performed by several methods. In conventional oil well wireline logging, a probe or “sonde” is lowered into the borehole after some or all of the well has been drilled, and is used to determine certain characteristics of the formations traversed by the borehole. The sonde may include one or more sensors to measure parameters downhole and typically is constructed as a hermetically sealed cylinder for housing the sensors, which hangs at the end of a long cable or “wireline.” The cable or wireline provides mechanical support to the sonde and also provides an electrical connection between the sensors and associated instrumentation within the sonde, and electrical equipment located at the surface of the well. Normally, the cable supplies operating power to the sonde and is used as an electrical conductor to transmit information signals from the sonde to the surface. In accordance with conventional techniques, various parameters of the earth's formations are measured and correlated with the position of the sonde in the borehole as the sonde is pulled uphole. While wireline logging is useful in assimilating information relating to formations downhole, it nonetheless has certain disadvantages. For example, before the wireline logging tool can be run in the wellbore, the drillstring and bottomhole assembly must first be removed or “tripped” from the borehole, resulting in considerable cost and loss of drilling time for the driller (who typically is paying daily fees for the rental of drilling equipment). Because of these limitations associated with wireline logging, there has been an emphasis on developing tools that could collect data during the drilling process itself. By collecting and processing data during the drilling process, without the necessity of tripping the drilling assembly to insert a wireline logging tool, the driller can make accurate modifications or corrections in “real-time” to optimize drilling performance. Designs for measuring conditions downhole and the movement and location of the drilling assembly, contemporaneously with the drilling of the well, have come to be known as “measurement-while-drilling” techniques, or “MWD.” Similar techniques, concentrating more on the measurement of formation parameters of the type associated with wireline tools, commonly have been referred to as “logging while drilling” techniques, or “LWD.” While distinctions between MWD and LWD may exist, the terms MWD and LWD often are used interchangeably. For the purposes of this disclosure, the term MWD will be used with the understanding that the term encompasses both the collection of formation parameters and the collection of information relating to the position of the drilling assembly while the bottomhole assembly is in the well. The sensors used in a wireline sonde or MWD logging tools usually include a source device for transmitting energy into the formation, and one or more receivers for detecting the energy reflected from the formation. Various sensors have been used to determine particular characteristics of the formation, including nuclear sensors, acoustic sensors, and electrical sensors. See generally J. Lab, A Practical Introduction to Borehole Geophysics (Society of Exploration Geophysicists 1986); D. R. Skinner, Introduction to Petroleum Production, Volume 1, at 54-63 (Gulf Publishing Co. 1981). For a formation to contain petroleum, and for the formation to permit the petroleum to flow through it, the rock comprising the formation must have certain well known physical characteristics. One measurable characteristic is the resistivity (or conductivity) of the formation. A variety of tool types are used for measuring resistivity. Induction tools are one type of resistivity tool generally known in the art. An induction tool comprises a pair of antenna coils, one of which transmits while the other receives. Induction tools measure the resistivity of the formation by measuring the current induced in the receiving antenna as a result of magnetic flux caused by current in the emitting antenna. Specifically, an alternating current with a known intensity is fed to the emitting coil or antenna. Current flow through the emitting coil induces currents in the formation that flow in coaxial loops around the tool. These currents in turn induce a signal in the receiving coil. This signal induced in the receiving coil can be measured and is generally proportional to the conductivity of the formation. Of similar construction is a second type of resistivity tool called an electromagnetic propagation (EMP) tool. These tools operate at much higher frequencies than induction tools (about 10 6 Hz as compared with about 10 4 Hz). EMP tools use transmitter coils to transmit radio frequency signals into the formation, and use receiver coils to measure the relative amplitude and phase of the signals received by the receivers. The formation resistivity causes changes in the intensity and timing of the transmitted wave, so the receiver does not receive an exact copy of the wave that the transmitter sent. Instead, the resistivity of the formation reduces (or “attenuates”) the intensity of the signal and causes a time delay (or “phase shift”) in the signal. Accordingly, the attenuation and phase shift can be measured at the receiver and used to gauge the resistivity of the formation. Higher frequency signals provide a higher measurement accuracy, but tend to have a reduced investigation depth. Consequently, when multiple transmitter coils are present, the transmitter-receiver configuration(s) with a shallower investigation depth may employ a higher frequency (e.g. 2 MHz) for better accuracy, and transmitter-receiver configuration(s) with deeper investigation depths may require a lower frequency (e.g. 0.5 MHz) for adequate performance. Resistivity derived from attenuation measurements is commonly called “attenuation resistivity,” and resistivity derived from phase measurements is commonly known as “phase resistivity.” See generally, James R. Jordan, et al., Well Logging II—Electric And Acoustic Logging, SPE Monograph Series, Volume 10, at 71-87 (1986). The various “beds” or layers in the earth have characteristic resistivities which can be used to identify their position. For example, in a so-called “shaley-sand” formation, the shale bed can have a low resistivity of about 1 ohm-m. A bed of oil-saturated sandstone, on the other hand, is likely to have a higher resistivity of about 10 ohm-m, or more. The sudden change in resistivity at the boundary between beds of shale and sandstone can be used to locate these boundaries. However, for relatively thin beds and deviated boreholes, this detection can be difficult to accomplish reliably. SUMMARY OF THE INVENTION Accordingly, there is provided herein a method and apparatus for identifying boundaries between thin beds having different resistivities. In one embodiment, the method includes (a) transmitting an oscillatory signal from a first transmitter; (b) determining a first phase difference between signals induced in two receivers by the oscillatory signal from the first transmitter; (c) transmitting an oscillatory signal from a second transmitter; (d) determining a second phase difference between signals induced in the two receivers by the oscillatory signal from the second transmitter; and (e) calculating a interferometric difference between the first and second phase differences. When the transmitters are symmetrically located with respect to the receivers, the interferometric difference exhibits a maximum or minimum value near the boundary location. This low-complexity method provides good boundary detection results when the bed thickness is larger than the transmitter-receiver spacing. In a second method embodiment, the interferometric difference is calculated from the logarithm of the measured attenuation. BRIEF DESCRIPTION OF THE DRAWINGS A better understanding of the present invention can be obtained when the following detailed description of the preferred embodiment is considered in conjunction with the following drawings, in which: FIG. 1 is a block diagram (in part) of a resistivity tool according to a preferred embodiment; FIG. 2 is a graph showing resistivity as a function of depth for a series of progressively thicker beds; FIG. 3 is a graph of apparent resistivity as indicated by measured attenuation and phase shift; FIG. 4 is a graph of interferometric differences in both phase and amplitude; FIG. 5 is graph of apparent resistivity for dipping beds; FIG. 6 is a graph of interferometric differences for dipping beds; FIG. 7 is a graph of interferometric phase differences for different receiver spacings; FIG. 8 is a graph of interferometric phase differences for different transmitter-receiver spacings; FIG. 9 is a graph of apparent phase resistivity for different signal frequencies; FIG. 10 is a flowchart of a method for measuring attenuation and/or phase shift in a resistivity tool; and FIG. 11 is a flowchart of a method for detecting bed boundaries. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As with all downhole well components, resistivity tools are exposed to a harsh environment that includes a wide temperature and pressure range. To avoid a correspondingly wide variation in tool performance, various compensation techniques are employed. One useful compensation technique for resistivity tools is to provide the tool with a symmetric configuration. It is herein proposed that the symmetric halves of such tools can be used in an “interfering” fashion to detect bed boundaries. Turning now to the figures, FIG. 1 shows a resistivity tool subassembly 102 . The subassembly 102 is provided with one or more regions 106 of reduced diameter. A wire coil 104 is placed in the region 106 and spaced away from the surface of subassembly 102 by a constant distance. To mechanically support and protect the coil 104 , a non-conductive filler material (not shown) such as epoxy, rubber, or ceramics may be used in the reduced diameter regions 106 . Coils 104 and 112 are transmitter coils, and coils 108 and 110 are receiving coils. In operation, transmitter coils 104 and 112 alternately transmit interrogating electromagnetic signals which propagate through the wellbore and surrounding formation. Receiver coils 108 , 110 detect the interrogating electromagnetic signals and provide a measure of the amplitude attenuation and phase shift between coils 108 and 110 . From the amplitude attenuation and phase shift, the resistivity of the formation can be estimated using conventional techniques. The transmitter and receiver coils may comprise as little as one loop of wire, although more loops may provide additional signal power. The distance between the coils and the tool surface is preferably in the range from {fraction (1/16)} inch to ¾ inch, but may be larger. The spacing D between the receiver coils 108 , 110 is preferably between 1 and 15 inches, and the transmitter-receiver spacing L is preferably between 10 and 30 inches. Oscillator 114 generates a sinusoidal signal. Amplifier 116 amplifies the sinusoidal signal and switch 118 routes the amplified signal through one of the impedance matching circuits 120 , 122 to the corresponding transmitter coil. Signals from the receiver coils 108 , 110 pass through corresponding impedance matching circuits 124 and 126 and are amplified by corresponding amplifiers 128 and 130 . Attenuation detector 134 measures the amplitude of the signals from the amplifiers 128 , 130 , and determines attenuation by finding the ratio of the signal amplitudes. Phase difference detector 132 measures the phase difference between the signals from amplifiers 128 , 130 . The digital signal processor 144 reads the attenuation and phase difference measurements from the detectors 132 , 134 . The digital signal processor controls the setting of switch 118 to measure the attenuation and/or phase shift of signals propagating from either transmitter. One implementation of attenuation detector 134 and phase difference detector 132 is described in U.S. Pat. No. 5,389,881 (Bittar, et. al.) which is hereby incorporated herein by reference. An exemplary flowchart of the software executed by the digital signal processor 144 is shown in FIG. 10 . Starting at block 202 , the digital signal processor sets switch 132 to select receiver 108 in block 204 . In block 206 , the digital signal processor sets switch 118 to select transmitter 104 . A pause is made in block 208 to allow the transient ringing of the coils to damp out. Then in block 210 the digital signal processor measures the attenuation and/or phase shift of the signal between receivers 108 , 110 . In block 216 , the digital signal processor selects transmitter 112 and pauses in block 218 to again allow the transient ringing of the coils to damp out. A determination of the attenuation and/or phase shift of the signal between receivers 110 , 108 is made in block 220 . The determined attenuation and phase shifts are provided to the downhole controller in block 226 , and the digital signal processor returns to block 206 . The downhole controller gathers the measurements from a variety of sensors including the resistivity sensor, encodes the measurements, and transmits the measurements to the surface, where they are combined with position information. The measurements are processed on the surface to determine downhole formation characteristics. FIG. 11 shows one method for processing the attenuation and phase shift measurements from the resistivity tool. A surface processor (typically a personal computer) retrieves the measurements and position information in block 232 . In block 234 , the surface processor calculates the apparent resistivity from the measurements, and plots the apparent resistivity as a function of the position. The apparent resistivity is the resistivity of a homogeneous formation that would produce the measured attenuation and/or phase shift. The apparent resistivity calculated from attenuation measurements is not necessarily the same as the apparent resistivity calculated from phase measurements. Accordingly, the apparent resistivity is also termed attenuation resistivity or phase resistivity to indicate the measurements upon which the calculation is based. In block 236 , the surface processor uses a straightforward interferometric processing technique described below to determine the presence and location of boundaries, and plots the boundaries on the apparent resistivity graph. This technique is much less computationally intensive than other techniques such as de-convolution. A derivation is now made to demonstrate how two symmetric halves of a resistivity tool can be used to provide compensation, and how those same halves can be used to calculate an interferometric measurement. An example of the compensated measurements and interferometric measurements for various device configurations will be discussed afterwards. The voltage induced in a receiver coil R by a signal in a transmitter coil T can be written: V=ξ T ξ R A e i(φ+Φ T +Φ R) ,  (1) where ξ T and ξ R are intrinsic efficiencies of the transmitter T and receiver R, respectively, and Φ T and Φ R are intrinsic phase shifts induced by the transmitter T and receiver R, respectively. In subsequent equations, subscripts “u” and “L” will be used to differentiate between the upper and lower transmitter and receiver coils. For example, T u designates the upper transmitter 104 , and R L designates the lower receiver 110 . The ideal amplitude A and ideal phase φ will be provided with subscripts “+” and “−” to indicate whether they correspond to the transmitter receiver spacing of L+(D/2) or L−(D/2) (L and D are shown in FIG. 1 ). The ratio between voltages induced in the two receiver coils from the upper transmitter is: V R L  T U V R U  T U = ξ R L ξ R U  η u     ( δϕ U + φ R L - φ R U ) , ( 2 ) where η U =A + /A − is the ideal attenuation, and δφ U =φ + −φ − is the ideal phase shift in the signal from the upper transmitter. Similarly, the ratio between voltages induced by the lower transmitter is: V R U  T L V R L  T L = ξ R U ξ R L  η L     ( δϕ L + φ R U - φ R L ) . ( 3 ) The intrinsic receiver efficiency and phase can be eliminated by combining equations (2) and (3) V R L  T U V R U  T U  V R U  T L V R L  T L = η u  η L     ( δϕ U + δϕ L ) / 2 . ( 4 ) Equation (4) therefore represents a way of compensating for variations in intrinsic efficiency and phase and to obtain correct attenuation and phase shift measurements when the formation is homogeneous (η U =η L and δφ U =δφ L ). It is important to eliminate the intrinsic circuit biases when absolute resistivity measurements are needed. However, boundary detection focuses on identifying sharp changes in resistivity. Accordingly, the attenuation and phase resistivity measurements using upper and lower transmitters can be combined in a different manner to highlight changes in phase and attenuation that are indicative of bed boundaries. Consider the situation where the center of the resistivity tool is positioned at a boundary between two thick seismic beds. The signals travelling from one transmitter to the receivers travel mostly through one bed, while the signals travelling to the receivers from the other transmitter travel mostly through the other bed. The attenuation and phase shifts of the signals are indicative of the resistivity of the beds through which they travel, and the difference between the attenuations and phase shifts is maximized when the tool is centered at the boundary. The difference decreases as the tool moves away from the boundary. To measure the variations in attenuation and phase shift, the amplitude and phase of equations (2) and (3) is measured, and the differences taken. The following interferometric variations are proposed: I (δφ)=(δφ u +Φ u −Φ L )=(δφ L +Φ L −Φ u )=δφ u −δφ L +2(Φ u −Φ L )  (5) I  ( ln     η ) = ln  ( ξ R L ξ R U  η u ) - ln  ( ξ R U ξ R L  η L ) = ln  ( η u ) - ln  ( η L ) + 2  ln  ( ξ R L ξ R U ) ( 6 ) The last term in each equation is relatively constant in the neighborhood of any given boundary. The preceding terms are equal in a homogeneous formation, but one always changes before the other as the tool crosses a boundary. Extreme values (local maximums and minimums) in the difference are indicative of the location of the boundary. FIG. 2 shows an actual resistance of a hypothetical series of formation beds that is used below to demonstrate the performance of the interferometric technique. The formation includes six “thin” beds with a resistivity of 10 Ω-m, separated by “shoulder” beds with a resistivity of 1 Ω-m. The low-resistivity beds are 4 feet thick, while the high-resistivity beds have varying thicknesses of ¼, ½, 1, 2, 3, and 4 feet. FIG. 3 shows apparent attenuation resistivity (broken line) and apparent phase resistivity (solid line) as measured by a compensated resistivity tool having L=25″ and D=10″ and operating at a frequency of 2 MHz. Actual bed boundaries are shown by vertical solid lines. FIG. 4 shows the interferometric attenuation (broken line) and phase shift (solid line) variations for the same tool configuration. For bed thicknesses less than 1 foot, the interferometric variation fails to accurately locate the boundaries. However, the peaks in the interferometric variations clearly correspond to the boundaries for thicknesses larger than 1 foot. The interferometric phase variation appears to provide a better sensitivity to the presence of boundaries than the interferometric attenuation variation. FIG. 5 shows the apparent attenuation resistivity and apparent phase resistivity for the same tool configuration when the tool encounters the beds at a 60° dip angle. It is noted that the boundary “horns” may cause difficulty in identifying the number and location of bed boundaries. FIG. 6 shows the interferometric attenuation and phase shift variations, and here a clear correspondence exists between the peaks in the interferometric phase shift variation and the bed boundaries. Returning to the original bed dip angle, FIG. 7 shows interferometric phase shift variation for tools with a varying receiver spacing of D=2″, 6″, 10″, and 14″. Although the peaks move slightly for thinner beds, the main effect of varying the receiver spacing is the increased amplitude of the peaks for shorter spacings. FIG. 8 shows interferometric phase shift variation for tools with a varying transmitter-receiver spacing of L=10″, 15″, and 25″. For the shorter spacings, the peaks much more closely correspond with the boundaries of thin beds, although a price is paid in terms of the amplitude of the peaks. It is noted that the shorter spacings allow significantly better boundary detection for bed thicknesses less than 1 foot. FIG. 9 shows the interferometric phase shift variation for two frequencies f=0.5 MHz and 2 MHz. The higher frequency has a higher amplitude and better correspondence of peaks to bed boundaries. It is noted that the interferometric differences can be found from the logarithm of the ratio of equations (2) and (3): ln  ( V R L  T U V R U  T U / V R U  T L V R L  T L ) = ln  [ ( ξ R L ξ R U ) 2  η u η L     ( δϕ U - δϕ L + 2  ( φ R L - φ R U ) ) ] ( 7 ) ln  ( V R L  T U V R U  T U / V R U  T L V R L  T L ) =    ln     η U - ln     η L + 2  ln  ( ξ R L ξ R U ) +      ( δϕ U - δϕ L + 2  ( φ R L - φ R U ) ) ( 8 ) ln  ( V R L  T U V R U  T U / V R U  T L V R L  T L ) = I  ( ln     η ) +      I  ( δϕ ) ( 9 ) Taking the magnitude of this logarithm effectively combines the interferometric differences, but the interferometric phase shift variation dominates. This interferometric magnitude may be preferred in some situations. Returning to FIG. 11, in block 236 the surface processor calculates the interferometric variations as a function of position, and identifies initial boundary locations at the local minimum and local maximum points. It may be preferred to establish predetermined thresholds relative to the average interferometric variation that the local maximum or local minimum must exceed before a boundary is identified. For example, the local maximum or minimum interferometric phase variation might be required to be at least 10 degrees away from the average variation, or the interferometric attenuation variation might be required to be 3 dB away from the average. In some embodiments, the surface processor will adjust the initial boundary locations if the bed is determined to have a thickness less than some threshold. While the present invention has been described and disclosed in terms of a preferred embodiment, it will be understood that variations in the details thereof can be made without departing from the scope of the invention.
A method and apparatus are disclosed for identifying boundaries between thin beds having different resistivities. In one embodiment, the method includes (a) transmitting an oscillatory signal from a first transmitter; (b) determining a first phase difference between signals induced in two receivers by the oscillatory signal from the first transmitter; (c) transmitting an oscillatory signal from a second transmitter; (d) determining a second phase difference between signals induced in the two receivers by the oscillatory signal from the second transmitter; and (e) calculating a interferometric difference between the first and second phase differences. When the transmitters are symmetrically located with respect to the receivers, the interferometric difference exhibits a maximum or minimum value near the boundary location. This low-complexity method provides good boundary detection results when the bed thickness is larger than the transmitter-receiver spacing. In a second method embodiment, the interferometric difference is calculated from the logarithm of the measured attenuation.
Identify the most important claim in the given context and summarize it
[ "TECHNICAL FIELD OF THE INVENTION The present invention relates generally to downhole tools for determining characteristics of the borehole and formation during or after the drilling of a well.", "More particularly, the present invention relates to a resistivity logging tool for measuring formation resistivity parameters.", "Still more particularly, the present invention relates to a method for processing resistivity measurement variables to improve the detection of bed boundaries.", "BACKGROUND OF THE INVENTION Modern petroleum drilling and production operations demand a great quantity of information relating to parameters and conditions downhole.", "Such information typically includes characteristics of the earth formations traversed by the wellbore, in addition to data relating to the size and configuration of the borehole itself.", "The collection of information relating to conditions downhole, which commonly is referred to as “logging,” can be performed by several methods.", "In conventional oil well wireline logging, a probe or “sonde”", "is lowered into the borehole after some or all of the well has been drilled, and is used to determine certain characteristics of the formations traversed by the borehole.", "The sonde may include one or more sensors to measure parameters downhole and typically is constructed as a hermetically sealed cylinder for housing the sensors, which hangs at the end of a long cable or “wireline.”", "The cable or wireline provides mechanical support to the sonde and also provides an electrical connection between the sensors and associated instrumentation within the sonde, and electrical equipment located at the surface of the well.", "Normally, the cable supplies operating power to the sonde and is used as an electrical conductor to transmit information signals from the sonde to the surface.", "In accordance with conventional techniques, various parameters of the earth's formations are measured and correlated with the position of the sonde in the borehole as the sonde is pulled uphole.", "While wireline logging is useful in assimilating information relating to formations downhole, it nonetheless has certain disadvantages.", "For example, before the wireline logging tool can be run in the wellbore, the drillstring and bottomhole assembly must first be removed or “tripped”", "from the borehole, resulting in considerable cost and loss of drilling time for the driller (who typically is paying daily fees for the rental of drilling equipment).", "Because of these limitations associated with wireline logging, there has been an emphasis on developing tools that could collect data during the drilling process itself.", "By collecting and processing data during the drilling process, without the necessity of tripping the drilling assembly to insert a wireline logging tool, the driller can make accurate modifications or corrections in “real-time”", "to optimize drilling performance.", "Designs for measuring conditions downhole and the movement and location of the drilling assembly, contemporaneously with the drilling of the well, have come to be known as “measurement-while-drilling”", "techniques, or “MWD.”", "Similar techniques, concentrating more on the measurement of formation parameters of the type associated with wireline tools, commonly have been referred to as “logging while drilling”", "techniques, or “LWD.”", "While distinctions between MWD and LWD may exist, the terms MWD and LWD often are used interchangeably.", "For the purposes of this disclosure, the term MWD will be used with the understanding that the term encompasses both the collection of formation parameters and the collection of information relating to the position of the drilling assembly while the bottomhole assembly is in the well.", "The sensors used in a wireline sonde or MWD logging tools usually include a source device for transmitting energy into the formation, and one or more receivers for detecting the energy reflected from the formation.", "Various sensors have been used to determine particular characteristics of the formation, including nuclear sensors, acoustic sensors, and electrical sensors.", "See generally J. Lab, A Practical Introduction to Borehole Geophysics (Society of Exploration Geophysicists 1986);", "D. R. Skinner, Introduction to Petroleum Production, Volume 1, at 54-63 (Gulf Publishing Co. 1981).", "For a formation to contain petroleum, and for the formation to permit the petroleum to flow through it, the rock comprising the formation must have certain well known physical characteristics.", "One measurable characteristic is the resistivity (or conductivity) of the formation.", "A variety of tool types are used for measuring resistivity.", "Induction tools are one type of resistivity tool generally known in the art.", "An induction tool comprises a pair of antenna coils, one of which transmits while the other receives.", "Induction tools measure the resistivity of the formation by measuring the current induced in the receiving antenna as a result of magnetic flux caused by current in the emitting antenna.", "Specifically, an alternating current with a known intensity is fed to the emitting coil or antenna.", "Current flow through the emitting coil induces currents in the formation that flow in coaxial loops around the tool.", "These currents in turn induce a signal in the receiving coil.", "This signal induced in the receiving coil can be measured and is generally proportional to the conductivity of the formation.", "Of similar construction is a second type of resistivity tool called an electromagnetic propagation (EMP) tool.", "These tools operate at much higher frequencies than induction tools (about 10 6 Hz as compared with about 10 4 Hz).", "EMP tools use transmitter coils to transmit radio frequency signals into the formation, and use receiver coils to measure the relative amplitude and phase of the signals received by the receivers.", "The formation resistivity causes changes in the intensity and timing of the transmitted wave, so the receiver does not receive an exact copy of the wave that the transmitter sent.", "Instead, the resistivity of the formation reduces (or “attenuates”) the intensity of the signal and causes a time delay (or “phase shift”) in the signal.", "Accordingly, the attenuation and phase shift can be measured at the receiver and used to gauge the resistivity of the formation.", "Higher frequency signals provide a higher measurement accuracy, but tend to have a reduced investigation depth.", "Consequently, when multiple transmitter coils are present, the transmitter-receiver configuration(s) with a shallower investigation depth may employ a higher frequency (e.g. 2 MHz) for better accuracy, and transmitter-receiver configuration(s) with deeper investigation depths may require a lower frequency (e.g. 0.5 MHz) for adequate performance.", "Resistivity derived from attenuation measurements is commonly called “attenuation resistivity,” and resistivity derived from phase measurements is commonly known as “phase resistivity.”", "See generally, James R. Jordan, et al.", ", Well Logging II—Electric And Acoustic Logging, SPE Monograph Series, Volume 10, at 71-87 (1986).", "The various “beds”", "or layers in the earth have characteristic resistivities which can be used to identify their position.", "For example, in a so-called “shaley-sand”", "formation, the shale bed can have a low resistivity of about 1 ohm-m.", "A bed of oil-saturated sandstone, on the other hand, is likely to have a higher resistivity of about 10 ohm-m, or more.", "The sudden change in resistivity at the boundary between beds of shale and sandstone can be used to locate these boundaries.", "However, for relatively thin beds and deviated boreholes, this detection can be difficult to accomplish reliably.", "SUMMARY OF THE INVENTION Accordingly, there is provided herein a method and apparatus for identifying boundaries between thin beds having different resistivities.", "In one embodiment, the method includes (a) transmitting an oscillatory signal from a first transmitter;", "(b) determining a first phase difference between signals induced in two receivers by the oscillatory signal from the first transmitter;", "(c) transmitting an oscillatory signal from a second transmitter;", "(d) determining a second phase difference between signals induced in the two receivers by the oscillatory signal from the second transmitter;", "and (e) calculating a interferometric difference between the first and second phase differences.", "When the transmitters are symmetrically located with respect to the receivers, the interferometric difference exhibits a maximum or minimum value near the boundary location.", "This low-complexity method provides good boundary detection results when the bed thickness is larger than the transmitter-receiver spacing.", "In a second method embodiment, the interferometric difference is calculated from the logarithm of the measured attenuation.", "BRIEF DESCRIPTION OF THE DRAWINGS A better understanding of the present invention can be obtained when the following detailed description of the preferred embodiment is considered in conjunction with the following drawings, in which: FIG. 1 is a block diagram (in part) of a resistivity tool according to a preferred embodiment;", "FIG. 2 is a graph showing resistivity as a function of depth for a series of progressively thicker beds;", "FIG. 3 is a graph of apparent resistivity as indicated by measured attenuation and phase shift;", "FIG. 4 is a graph of interferometric differences in both phase and amplitude;", "FIG. 5 is graph of apparent resistivity for dipping beds;", "FIG. 6 is a graph of interferometric differences for dipping beds;", "FIG. 7 is a graph of interferometric phase differences for different receiver spacings;", "FIG. 8 is a graph of interferometric phase differences for different transmitter-receiver spacings;", "FIG. 9 is a graph of apparent phase resistivity for different signal frequencies;", "FIG. 10 is a flowchart of a method for measuring attenuation and/or phase shift in a resistivity tool;", "and FIG. 11 is a flowchart of a method for detecting bed boundaries.", "While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.", "It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As with all downhole well components, resistivity tools are exposed to a harsh environment that includes a wide temperature and pressure range.", "To avoid a correspondingly wide variation in tool performance, various compensation techniques are employed.", "One useful compensation technique for resistivity tools is to provide the tool with a symmetric configuration.", "It is herein proposed that the symmetric halves of such tools can be used in an “interfering”", "fashion to detect bed boundaries.", "Turning now to the figures, FIG. 1 shows a resistivity tool subassembly 102 .", "The subassembly 102 is provided with one or more regions 106 of reduced diameter.", "A wire coil 104 is placed in the region 106 and spaced away from the surface of subassembly 102 by a constant distance.", "To mechanically support and protect the coil 104 , a non-conductive filler material (not shown) such as epoxy, rubber, or ceramics may be used in the reduced diameter regions 106 .", "Coils 104 and 112 are transmitter coils, and coils 108 and 110 are receiving coils.", "In operation, transmitter coils 104 and 112 alternately transmit interrogating electromagnetic signals which propagate through the wellbore and surrounding formation.", "Receiver coils 108 , 110 detect the interrogating electromagnetic signals and provide a measure of the amplitude attenuation and phase shift between coils 108 and 110 .", "From the amplitude attenuation and phase shift, the resistivity of the formation can be estimated using conventional techniques.", "The transmitter and receiver coils may comprise as little as one loop of wire, although more loops may provide additional signal power.", "The distance between the coils and the tool surface is preferably in the range from {fraction (1/16)} inch to ¾ inch, but may be larger.", "The spacing D between the receiver coils 108 , 110 is preferably between 1 and 15 inches, and the transmitter-receiver spacing L is preferably between 10 and 30 inches.", "Oscillator 114 generates a sinusoidal signal.", "Amplifier 116 amplifies the sinusoidal signal and switch 118 routes the amplified signal through one of the impedance matching circuits 120 , 122 to the corresponding transmitter coil.", "Signals from the receiver coils 108 , 110 pass through corresponding impedance matching circuits 124 and 126 and are amplified by corresponding amplifiers 128 and 130 .", "Attenuation detector 134 measures the amplitude of the signals from the amplifiers 128 , 130 , and determines attenuation by finding the ratio of the signal amplitudes.", "Phase difference detector 132 measures the phase difference between the signals from amplifiers 128 , 130 .", "The digital signal processor 144 reads the attenuation and phase difference measurements from the detectors 132 , 134 .", "The digital signal processor controls the setting of switch 118 to measure the attenuation and/or phase shift of signals propagating from either transmitter.", "One implementation of attenuation detector 134 and phase difference detector 132 is described in U.S. Pat. No. 5,389,881 (Bittar, et.", "al.) which is hereby incorporated herein by reference.", "An exemplary flowchart of the software executed by the digital signal processor 144 is shown in FIG. 10 .", "Starting at block 202 , the digital signal processor sets switch 132 to select receiver 108 in block 204 .", "In block 206 , the digital signal processor sets switch 118 to select transmitter 104 .", "A pause is made in block 208 to allow the transient ringing of the coils to damp out.", "Then in block 210 the digital signal processor measures the attenuation and/or phase shift of the signal between receivers 108 , 110 .", "In block 216 , the digital signal processor selects transmitter 112 and pauses in block 218 to again allow the transient ringing of the coils to damp out.", "A determination of the attenuation and/or phase shift of the signal between receivers 110 , 108 is made in block 220 .", "The determined attenuation and phase shifts are provided to the downhole controller in block 226 , and the digital signal processor returns to block 206 .", "The downhole controller gathers the measurements from a variety of sensors including the resistivity sensor, encodes the measurements, and transmits the measurements to the surface, where they are combined with position information.", "The measurements are processed on the surface to determine downhole formation characteristics.", "FIG. 11 shows one method for processing the attenuation and phase shift measurements from the resistivity tool.", "A surface processor (typically a personal computer) retrieves the measurements and position information in block 232 .", "In block 234 , the surface processor calculates the apparent resistivity from the measurements, and plots the apparent resistivity as a function of the position.", "The apparent resistivity is the resistivity of a homogeneous formation that would produce the measured attenuation and/or phase shift.", "The apparent resistivity calculated from attenuation measurements is not necessarily the same as the apparent resistivity calculated from phase measurements.", "Accordingly, the apparent resistivity is also termed attenuation resistivity or phase resistivity to indicate the measurements upon which the calculation is based.", "In block 236 , the surface processor uses a straightforward interferometric processing technique described below to determine the presence and location of boundaries, and plots the boundaries on the apparent resistivity graph.", "This technique is much less computationally intensive than other techniques such as de-convolution.", "A derivation is now made to demonstrate how two symmetric halves of a resistivity tool can be used to provide compensation, and how those same halves can be used to calculate an interferometric measurement.", "An example of the compensated measurements and interferometric measurements for various device configurations will be discussed afterwards.", "The voltage induced in a receiver coil R by a signal in a transmitter coil T can be written: V=ξ T ξ R A e i(φ+Φ T +Φ R) , (1) where ξ T and ξ R are intrinsic efficiencies of the transmitter T and receiver R, respectively, and Φ T and Φ R are intrinsic phase shifts induced by the transmitter T and receiver R, respectively.", "In subsequent equations, subscripts “u”", "and “L”", "will be used to differentiate between the upper and lower transmitter and receiver coils.", "For example, T u designates the upper transmitter 104 , and R L designates the lower receiver 110 .", "The ideal amplitude A and ideal phase φ will be provided with subscripts “+”", "and “−”", "to indicate whether they correspond to the transmitter receiver spacing of L+(D/2) or L−(D/2) (L and D are shown in FIG. 1 ).", "The ratio between voltages induced in the two receiver coils from the upper transmitter is: V R L  T U V R U  T U = ξ R L ξ R U  η u     ( δϕ U + φ R L - φ R U ) , ( 2 ) where η U =A + /A − is the ideal attenuation, and δφ U =φ + −φ − is the ideal phase shift in the signal from the upper transmitter.", "Similarly, the ratio between voltages induced by the lower transmitter is: V R U  T L V R L  T L = ξ R U ξ R L  η L     ( δϕ L + φ R U - φ R L ) .", "( 3 ) The intrinsic receiver efficiency and phase can be eliminated by combining equations (2) and (3) V R L  T U V R U  T U  V R U  T L V R L  T L = η u  η L     ( δϕ U + δϕ L ) / 2 .", "( 4 ) Equation (4) therefore represents a way of compensating for variations in intrinsic efficiency and phase and to obtain correct attenuation and phase shift measurements when the formation is homogeneous (η U =η L and δφ U =δφ L ).", "It is important to eliminate the intrinsic circuit biases when absolute resistivity measurements are needed.", "However, boundary detection focuses on identifying sharp changes in resistivity.", "Accordingly, the attenuation and phase resistivity measurements using upper and lower transmitters can be combined in a different manner to highlight changes in phase and attenuation that are indicative of bed boundaries.", "Consider the situation where the center of the resistivity tool is positioned at a boundary between two thick seismic beds.", "The signals travelling from one transmitter to the receivers travel mostly through one bed, while the signals travelling to the receivers from the other transmitter travel mostly through the other bed.", "The attenuation and phase shifts of the signals are indicative of the resistivity of the beds through which they travel, and the difference between the attenuations and phase shifts is maximized when the tool is centered at the boundary.", "The difference decreases as the tool moves away from the boundary.", "To measure the variations in attenuation and phase shift, the amplitude and phase of equations (2) and (3) is measured, and the differences taken.", "The following interferometric variations are proposed: I (δφ)=(δφ u +Φ u −Φ L )=(δφ L +Φ L −Φ u )=δφ u −δφ L +2(Φ u −Φ L ) (5) I  ( ln   η ) = ln  ( ξ R L ξ R U  η u ) - ln  ( ξ R U ξ R L  η L ) = ln  ( η u ) - ln  ( η L ) + 2  ln  ( ξ R L ξ R U ) ( 6 ) The last term in each equation is relatively constant in the neighborhood of any given boundary.", "The preceding terms are equal in a homogeneous formation, but one always changes before the other as the tool crosses a boundary.", "Extreme values (local maximums and minimums) in the difference are indicative of the location of the boundary.", "FIG. 2 shows an actual resistance of a hypothetical series of formation beds that is used below to demonstrate the performance of the interferometric technique.", "The formation includes six “thin”", "beds with a resistivity of 10 Ω-m, separated by “shoulder”", "beds with a resistivity of 1 Ω-m.", "The low-resistivity beds are 4 feet thick, while the high-resistivity beds have varying thicknesses of ¼, ½, 1, 2, 3, and 4 feet.", "FIG. 3 shows apparent attenuation resistivity (broken line) and apparent phase resistivity (solid line) as measured by a compensated resistivity tool having L=25″ and D=10″ and operating at a frequency of 2 MHz.", "Actual bed boundaries are shown by vertical solid lines.", "FIG. 4 shows the interferometric attenuation (broken line) and phase shift (solid line) variations for the same tool configuration.", "For bed thicknesses less than 1 foot, the interferometric variation fails to accurately locate the boundaries.", "However, the peaks in the interferometric variations clearly correspond to the boundaries for thicknesses larger than 1 foot.", "The interferometric phase variation appears to provide a better sensitivity to the presence of boundaries than the interferometric attenuation variation.", "FIG. 5 shows the apparent attenuation resistivity and apparent phase resistivity for the same tool configuration when the tool encounters the beds at a 60° dip angle.", "It is noted that the boundary “horns”", "may cause difficulty in identifying the number and location of bed boundaries.", "FIG. 6 shows the interferometric attenuation and phase shift variations, and here a clear correspondence exists between the peaks in the interferometric phase shift variation and the bed boundaries.", "Returning to the original bed dip angle, FIG. 7 shows interferometric phase shift variation for tools with a varying receiver spacing of D=2″, 6″, 10″, and 14″.", "Although the peaks move slightly for thinner beds, the main effect of varying the receiver spacing is the increased amplitude of the peaks for shorter spacings.", "FIG. 8 shows interferometric phase shift variation for tools with a varying transmitter-receiver spacing of L=10″, 15″, and 25″.", "For the shorter spacings, the peaks much more closely correspond with the boundaries of thin beds, although a price is paid in terms of the amplitude of the peaks.", "It is noted that the shorter spacings allow significantly better boundary detection for bed thicknesses less than 1 foot.", "FIG. 9 shows the interferometric phase shift variation for two frequencies f=0.5 MHz and 2 MHz.", "The higher frequency has a higher amplitude and better correspondence of peaks to bed boundaries.", "It is noted that the interferometric differences can be found from the logarithm of the ratio of equations (2) and (3): ln  ( V R L  T U V R U  T U / V R U  T L V R L  T L ) = ln  [ ( ξ R L ξ R U ) 2  η u η L     ( δϕ U - δϕ L + 2  ( φ R L - φ R U ) ) ] ( 7 ) ln  ( V R L  T U V R U  T U / V R U  T L V R L  T L ) =  ln   η U - ln   η L + 2  ln  ( ξ R L ξ R U ) +    ( δϕ U - δϕ L + 2  ( φ R L - φ R U ) ) ( 8 ) ln  ( V R L  T U V R U  T U / V R U  T L V R L  T L ) = I  ( ln   η ) +    I  ( δϕ ) ( 9 ) Taking the magnitude of this logarithm effectively combines the interferometric differences, but the interferometric phase shift variation dominates.", "This interferometric magnitude may be preferred in some situations.", "Returning to FIG. 11, in block 236 the surface processor calculates the interferometric variations as a function of position, and identifies initial boundary locations at the local minimum and local maximum points.", "It may be preferred to establish predetermined thresholds relative to the average interferometric variation that the local maximum or local minimum must exceed before a boundary is identified.", "For example, the local maximum or minimum interferometric phase variation might be required to be at least 10 degrees away from the average variation, or the interferometric attenuation variation might be required to be 3 dB away from the average.", "In some embodiments, the surface processor will adjust the initial boundary locations if the bed is determined to have a thickness less than some threshold.", "While the present invention has been described and disclosed in terms of a preferred embodiment, it will be understood that variations in the details thereof can be made without departing from the scope of the invention." ]
BACKGROUND OF THE INVENTION The present invention concerns a microwave dielectric ceramic composition and, more in particular, it relates to a microwave dielectric ceramic composition having a temperature coefficient of a resonance frequency (hereinafter simply referred to as τf) varied generally within a practical characteristic range while maintaining a practical unload Q (hereinafter simply referred to Qu) and a greatly improved specific dielectric constant (hereinafter simply referred to as εr). The present invention also concerns a microwave dielectric ceramic composition in which each of the characteristic is balanced at a practical level. The present invention further concerns a microwave dielectric ceramic composition in which εr and Qu are controlled generally within a practical characteristic range while maintaining τf at a practical high level and each of the characteristics is balanced at a high level. The present invention further concerns a microwave dielectric ceramic composition in which εr, Qu and τf are controlled generally within a practical characteristic range and each of the characteristics is maintained in a well balanced state. The present invention is utilized for impedance matching or the like of dielectric resonators, microwave integrated circuit substrate, various kinds of microwave circuits in a microwave region and it is particularly suitable to LC filter materials. Generally, LC filter materials, dielectric resonators, dielectric substrates used in a region of high frequency waves such as microwaves or milliwaves are required to have high εr and high flu, as well as small absolute value for the temperature coefficient of the resonance frequency. Namely, since the dielectric loss of a microwave dielectric ceramic composition (hereinafter simply referred to as dielectric ceramic composition) tends to increase as the working frequency becomes higher, a dielectric ceramic composition having large εr and Qu in a microwave region is desired. For such a dielectric ceramic composition, a composition belonging to a composite perovskite structure such as Ba(Zn 1/3 Ta 2/3 )O 3 or Ba(Mg 1/3 Ta 2/3 )O 3 or BaO--TiO 2 system composition has been used in recent years, but any of them requires a high sintering temperature of 1300° C. or higher. Such a high sintering temperature requires greater power electric power consumption during sintering to result in a drawback of causing a disadvantage in view of production cost or productivity. Further, in a case of sintering together with a conductor having a low melting point as an electrode, for example, silver (melting point: 961° C.) or copper (melting point: 1083° C.) as in an LC filter or a strip line filter, it is particularly advantageous that the sintering temperature is lower than the melting point of the conductor. Accordingly, a material sinterable at a temperature as low as possible is demanded. SUMMARY OF THE INVENTION An object of the present invention is to provide a dielectric ceramic composition capable of having τf varying generally within a practical range and high εr while maintaining high Qu by a composition comprising a main ingredient of Bi 2 O 3 --Nb 2 O 5 --Ta 2 O 5 system and a predetermined amount of V 2 O 5 added and incorporated thereto. The present inventor has made various studies on Bi 2 O 3 ---Nb 2 O 5 --Ta 2 O 5 system compositions having τf varied generally within a practical characteristic range while maintaining high Qu, having high εr and capable of being produced by sintering at a low temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can be attained by varying the ratio between Nb 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 thereto. That is, the dielectric ceramic composition according to the present invention comprises a composition represented by xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ) in which 0.45≦x≦0.55 and 0<y<1.0 as a main ingredient, to which not more than 0.8 parts by weight (not including 0 part by weight) of V 2 O 5 s is added and incorporated based on 100 parts by weight of the xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ). In the above-mentioned invention, x is defined as 0.45 to 0.55, because Qu is too small if x is less than 0.45 or exceeds 0.55. Further, y is within a range: 0<y<1.0. If Nb 2 O 5 is not present (y=0), the absolute value for τf tends to increase (decrease in a negative direction) and εr tends to decrease. If N 2 O 5 is present even in a small amount, εr which is important for LC filter material tends to be improved. On the other hand if y is at 1.0, εr tends to decrease and Qu tends to decrease as y increases. Further, the addition ratio of V 2 O 5 is defined as not more than 0.8% by weight (not including 0% by weight), because Qu tends to decrease if it is added in excess of 0.8% by weight although the addition of V 2 O 5 can lower the sintering temperature. Further, a case in which α is 0% by weight, that is, of V 2 O 5 is not added is excluded, because this makes sintering insufficient and lowers each of the characteristics. The addition amount of V 2 O 5 at 0.4% by weight is more preferred since Qu increases much higher as compared with the case of addition of 0.8% by weight, 0.6% by weight and 0.2% by weight (Nos. 5-8 compared with Nos. 13-16, Nos. 9-12 and 1-4 in Table 1). In particular, it is preferred that x is from 0.47 to 0.53, y is from 0.4 to 0.8 and α is from 0.4 to 0.6, since each physical property is balanced. In this case, εr is from 42.9 to 47.7, Qu is from 790 to 1490 and τf is from -46.4 to -16.2 ppm/°C. Further, the dielectric ceramic composition of the present invention is produced as described below. Specifically, bismuth oxide (III) powder, niobium oxide (V) powder, tantalum oxide (V) powder and vanadium oxide (V) powder are mixed so as to provide a composition comprising a composition represented by xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 in which 0.45≦x≦0.55 and 0<y<1.0 as a main ingredient, to which not more than 0.8 parts by weight (not including 0 part by weight) of V 2 O 5 is added and incorporated based on 100 parts by weight of the xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ) and then calcined to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 860°-950° C. The sintering temperature is defined as within 860° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range. Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter. The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere. In the dielectric ceramic composition according to the present invention, τf can be varied widely within a practical characteristic range while maintaining Qu at a level with no practical problem by setting each of the oxides a predetermined ratio in the Bi 2 O 3 --Nb 2 O 5 --Ta 2 O 5 system, to which a predetermined amount of V 2 O 5 is added. Further, a dielectric ceramic composition having extremely high εr and suitable to LC filter material can be obtained. Further, the dielectric ceramic composition according to the present invention can be prepared by sintering at a relatively low temperature as 860° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor. An object of the present invention is to provide a dielectric ceramic composition in which (Qu and τf are controlled within a wide characteristic range while maintaining εr at a high and each of the characteristics is balanced at a practical level, by with a composition comprising Bi(NbTa)O 4 as a main ingredient to which V 2 O 5 and PbO is added each in a predetermined amount. The present inventor has made various studies on Bi(NbTa)O 4 system compositions having Qu and τf cotroled within a wide practical characteristic range while maintaining high εr and capable of being produced by sintering at a low and wide temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can be attained by varying the ratio between Nb 2 O 5 and Ta 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 and PhO thereto. The dielectric ceramic composition of the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 in which 0<x≦0.96 as a main ingredient to which not more than 5% by weight (not including 0% by weight) of V 2 O 5 and not more than 2% by weight (not including 0% by weight) of PbO are added and incorporated based on 100% by weight of Bi(NbxTa1-x)O 4 . In the above-mentioned invention, x is defined as: 0<x≦0.96, because the Ta 2 O 5 ingredient is substantially absent if x exceeds 0.96, making it difficult to control εr and τf. Further, the addition amount of V 2 O 5 is defined as greater than 0 and not more than 5% by weight, because addition in excess of 5% by weight can not provide any further effect and it rather results in deterioration of other characteristics such as Qu, although the sintering temperature can be lowered by the addition of V 2 O 5 , and because sintering is insufficient to lower each of the characteristics if V 2 O 5 is not added. The addition amount of V 2 O 5 within a range from 0.2 to 2.0% by weight is more preferred since a practical dielectric ceramic composition showing well balanced in each of the characteristics can be obtained. Further, the addition amount of PbO is greater than 0 and not more than 2% by weight. Addition of PbO can increase εr and Qu as compared with a case of not adding PbO at all. However, although εr is improved in proportion with the addition amount of PbO, Qu reaches a peak at the addition amount of 0.2% by weight and tends to reduce beyond the peak, τf tends to increase in the negative direction in proportion with the addition of PbO. This trend is remarkable if the addition amount is as great as 1 to 2% by weight. Accordingly, for obtaining a dielectric ceramic composition well balanced in each of the characteristics and having a high level, it is preferred that the addition amount of PbO is within a range from 0.1 to 1.0% by weight. Further, it is preferred that x is from 0.2 to 0.9 (table 1 and 2), the addition amount of V 2 O 5 is from 0.2 to 2.0% by weight and the addition amount of PbO is from 0.2 to 0.6% by weight (table 3). In this case, εr is from 45 to 48, Qu is from 960 to 1640 (at from 3.6 to 4.0 GHz) and τf is from -47 to -36 ppm/°C. Further, the dielectric ceramic composition of the present invention is produced as described below. The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 850°-950° C. The sintering temperature is defined as within 850° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range. Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter. The sintering can he carried out either in an ambient atmosphere or a reducing atmosphere. In the dielectric ceramic composition according to the present invention, a dielectric ceramic composition well balanced in each of the characteristics such as Qu and τf while maintaining practically high εr and suitable to LC filter material can be obtained by setting each of the oxides at a predetermined ratio in the Bi(NbTa)O 4 system, to which V 2 O 5 and PbO are added each in a predetermined amount. Further, a composition of particularly excellent performance can he obtained in a range of relatively lower addition amount of PbO. Further, the dielectric ceramic composition according to the present invention can he prepared by sintering at a relatively low and wide temperature as 850° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor. An object of the present invention is to provide a dielectric ceramic composition in which εr and Qu are controlled widely within a practical characteristic range while maintaining τf at a practically high level and each of the characteristics is balanced at a high level, by a composition comprising a Bi(NbTa)O 4 system as a main ingredient to which V 2 O 5 and MnO 2 are added and incorporated each by a predetermined amount. The present inventor has made various studies on Bi(NbTa)O 4 system compositions having εr and Qu cotroled widely within a practical characteristic range while maintaining practical high τf and capable of being produced by sintering at a low and wide temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can be attained by varying the ratio between Nb 2 O 5 and Ta 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 and MnO 2 thereto. The dielectric ceramic composition according to the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 in which 0<x ≦0.96 as a main ingredient, to which not more than 5% by weight (not including 0% by weight) of V 2 O 5 and not more than by weight (not including 0% by weight) of MnO 2 are added and incorporated based on 100% by weight of Bi(NbxTa1-x)O 4 . Further, in the present invention, the addition amount of MnO 2 may be from 0.1 to 1.0% by weight based on 100% by weight of Bi(NbxTa1-x)O 4 . In the above-mentioned invention, x is defined as: 0<x≦0.96, because the Ta 2 O 5 ingredient is substantially absent if x exceeds 0.96, making it difficult to control εr and τf. Further, the addition amount of V 2 O 5 is defined as greater than 0 and not more than 5% by weight, because addition in excess of 5% by weight can not provide any further effect and it rather results in deterioration of other characteristics such as Qu, although the sintering temperature can be lowered by the addition of V 2 O 5 , and because sintering is insufficient to lower each of the characteristics if V 2 O 5 is not added. The addition amount of V 2 O 5 within a range from 0.2 to 2.0% by weight is more preferred since a practical dielectric ceramic composition showing well balanced in each of the characteristics can be obtained. The addition amount of MnO 2 is more than 0 and not more than 2% by weight and the addition of MnO 2 can improve all of τf, εr and Qu with a certain exception as compared with a case of not adding MnO 2 at all. However, although εr is improved linearly in proportion with the addition mount of MnO 2 , τf rather decreases depending on the case as the addition amount of τf exceeds 1% by weight, particularly, as the sintering temperature goes higher, while Qu reaches a peak at the addition amount of 0.2% by weight and tends to lower beyond the peak. Accordingly, for obtaining a dielectric ceramic composition well balanced in each of the characteristics at a high level, it is preferred that the addition amount of MnO 2 is within a range from 0.1 to 1.0% by weight Further, it is preferred that x is from 0.2 to 0.9 (tables 1 and 2), the addition amount of V 2 O 5 is from 0.2 to 2.0% by weight and the addition amount of MnO 2 is from 0.1 to 0.6% by weight (table 4). In this case, εr is from 45 to 47, Qu is from 970 to 1640 (at from 3.6 to 3.9 GHz) and τf is from -14 to -5.5 ppm/°C. Further, the dielectric ceramic composition of the present invention is produced as described below. The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 850°-950° C. The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere. The sintering temperature is defined as within 850° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range. Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter. In the dielectric ceramic composition according to the present invention, a dielectric ceramic composition well balanced in each of the characteristics such as εr and Qu while maintaining practically high τf and suitable to LC filter material can be obtained by setting each of the oxides at a predetermined ratio in the Bi(NbTa)O 4 system, to which V 2 O 5 and MnO 2 are added each in a predetermined amount. Further, a composition of particularly excellent performance can be obtained in a range of relatively lower addition amount of MnO2. Further, the dielectric ceramic composition according to the present invention can be prepared by sintering at a relatively low and wide temperature as 850° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor. An object of the present invention is to provide a microwave dielectric ceramic composition in which εr, Qu and τf are controlled widely within a practical characteristic range and each of the characteristics is maintained in a well balanced state, by a composition comprising Bi(NbTa)O 4 system as a main ingredient to which V 2 O 5 and TiO 2 are added each in a predetermined amount. The present inventor has made various studies on Bi(NbTa)O 4 system compositions having εr, Qu and τf cotroled within a wide practical characteristic range and capable of being produced by sintering at a low temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can be attained by varying the ratio between Nb 2 O 5 and Ta 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 and TiO 2 thereto, and in particular the discovery that the foregoing object can be attained by cotroling τ f by an addition of TiO 2 . The dielectric ceramic composition according to the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 ) in which 0<x≦0.96 as a main ingredient to which not more than 2% by weight (not including 0% by weight) of V 2 O 5 and not more than 1% by weight (not including 0% by weight) of TiO 2 are added and incorporated based on 100% by weight of the Bi(NbxTa1-x)O 4 ). In the above-mentioned invention, x is defined as: 0<x≦0.96, because the Ta 2 O 5 ingredient is substantially absent if x exceeds 0.96, making it difficult to control εr and τf. By varying the addition amount of Ta 2 O 5 , control for εr and τf is facilitated and, particularly, by increasing the addition amount of Ta 2 O 5 , εr and Qu can be increased. Further, the addition amount of V 2 O 5 is determined as more than 0 but not more than 2% by weight, because V 2 O 5 functions as a sintering aid and, accordingly, can lower the sintering temperature and stabilize the performance by the addition, but addition in excess of 2% by weight decreases Qu and τf, whereas no addition of V 2 O 5 makes sintering insufficient and decreases each of the characteristics. The addition amount of V 2 O 5 , particularly, within a range from 0.3 to 0.5% by weight (particularly around 0.4% by weight) is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics is obtained. Further, the addition amount of TiO 2 is defined as not more than 1% by weight, because each of the characteristics decreases remarkably if the addition amount exceeds about 1% by weight. TiO 2 has an effect of transferring τf from a negative to positive direction by the addition and an addition amount within a range from 0.1 to 0.3% weight (particularly, 0.2% by weight) is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics is obtained. Further, x is from 0.6 to 0.96, the addition amount of V 2 O 5 may be from 0.2 to 1.0% by weight and the addition amount of TiO 5 may be from 0.1 to 0.6% by weight. This is because well balanced performance can be obtained for εr, Qu and τf within such a range of addition. Further, a practical balanced performance such as τf from -30 to 0 ppm/°C., Qu from 510 to 1160, εr from 42 to 58 can be obtained with the above-mentioned composition. Further, the dielectric ceramic composition of the present invention is produced as described below. The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined at 600°-800° C. to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 875°-950° C. The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere. The sintering temperature is defined as within 875° to 950° C., because a sintering temperature of less than 875° C. may make sintering insufficient, a sufficient sintering density is ensured by sintering within this sintering range and the performance is stabilized. Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter. In the dielectric composition according to the present invention, εr, Qu and τf are within a practical characteristic range and each of the characteristics is maintained in a well balanced state. Accordingly, it is suitable to the LC filter material. Further, the dielectric ceramic composition according to the present invention can be prepared by sintering at a relatively low and wide temperature as 875° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor. An object of present invention is to provide a microwave dielectric ceramic composition in which εr, Qu and τf are controlled within a wide practical characteristic range and each of the characteristics is maintained in a well balanced state, by a composition comprising a Bi(NbTa)O 4 system as a main ingredient, to which V 2 O 5 and MnO 2 , as well as TiO 2 or PbO are added and incorporated each in a predetermined amount. The present inventor has made various studies on Bi(NbTa)O 4 system compositions having εr, Qu and τf cotroled widely within a practical characteristic range and capable of being produced by sintering at a low temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can he attained by varying the ratio between Nb 2 O 5 and Ta 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 , MnO 2 and TiO 2 (or PbO) thereto. The dielectric ceramic composition according to the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 in which 0<x≦0.96 as a main ingredient, to which not more than 2% by weight (not including 0% by weight) of V 2 O 5 , not more than 2% by weight (not including 0% by weight) of MnO 2 and not more than 0.7% by weight (not including 0% by weight) of TiO 2 are added and incorporated based on 100% by weight of Bi(NbxTa 1 -x)O 4 . In the above-mentioned invention, x is defined as: 0<x≦0.96, because the Ta 2 O 5 ingredient is substantially absent if x exceeds 0.96, making it difficult to control εr and τf. Since V 2 O 5 functions as a sintering aid, addition thereof can lower the sintering temperature and stabilize the performance. If the addition amount of V 2 O 5 exceeds 2% by weight, it decreases Qu and τf, whereas if V 2 O 5 is not added, sintering is insufficient to decrease each of the characteristics. An addition amount of V 2 O 5 , particularly, from 0.2 to 1.0% by weight (preferably, from 0.3 to 0.5% by weight, more preferably, about 0.4% by weight) is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained. For instance, at the addition amount: (1) from 0.2 to 1.0% by weight (MnO 2 and TiO 2 : both 0.2% by weight, x: 0.8), εr is 46.6 to 47.9, Qu is 890 to 1300 as τf is -10.91 to -2.45 ppm/°C. and (2) addition amount of 0.4% by weight (MnO 2 and TiO 2 : both 0.2% by weight, x: 0.8), εr is 47.1, Qu is 1325 and τf is -7.46 ppm/°C. Further, both of Qu and τf are improved by the addition of MnO 2 up to 0.4% by weight. Accordingly, since MnO 2 has an effect of transferring τf from negative to positive direction within this addition range, it is effective to adjust τf from negative to positive direction. On the other hand, if it is added by more than 2% by weight, it is not preferred since tends to decrease greatly. Particularly, an addition amount of not more than 1.0% by weight is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained. For instance, at the addition amount of from 0.2 to 1.0% by weight (V 2 O 5 ; 0.4% by weight, TiO 2 ; 0.2% by weight, x; 0.8), εr is 47.0 to 47.5, Qu is 900 to 1440 and τf is -6.0 to -11.1 ppm/°C. Further, the addition amount of TiO 2 is defined as not more than 0.7% by weight, because Qu is decreases greatly and τf transfers in the positive direction apart from 0 if the addition amount is more than 0.7% by weight. Since TiO 2 has an effect of transferring τf from negative to positive direction by the addition, it is effective for adjusting τf from negative to positive direction. Particularly, a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained with an addition amount of 0.1 to 0.2% by weight. For instance, at the addition amount from 0.1 to 0.2% by weight (V 2 O 5 ; 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8), εr is46.4 to 47.1, Qu is 1320 to 1490 and τf is -8.8 to -7.5 ppm/°C. Further, it is possible to set the addition amount of V 2 O 5 as 0.2 to 1.0% by weight, the addition amount of MnO 2 of not more than 1.0% by weight and the addition amount of TiO 2 of not more than 0.4% by weight and x as 0.8 to 0.96, because the performance is well balanced in this case. For instance, it is possible to attain τf: -12 to +7 ppm/°C., Qu: 800 to 1600 and εr: 45 to 50. Further, the dielectric ceramic composition of the present invention is produced as described below. The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined at 600°-800° C. to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 850°-950° C. The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere. The sintering temperature is defined as within 850° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range. Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter. A dielectric ceramic composition according to the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 , in which 0<x≦0.96 as a main ingredient, to which 0.2 to 1% by weight of V 2 O 5 , not more than 1% by weight (not including 0% by weight) of MnO 2 and not more than 0.5% by weight (not including 0% by weight) of PbO are added and incorporated. The reason why x is defined as 0<x≦0.96 in this invention is identical with the reason explained for the first invention. Further, since V 2 O 5 functions as a sintering aid, addition thereof can lower the sintering temperature and stabilize the performance. If the addition amount exceeds 1% by weight, Qu decreases and it decreases remarkably to about 510 at the addition amount of 3% by weight. Further, if the addition amount exceeds 1% by weight, τf is not more than -24 ppm/°C., that is, increases toward the negative direction. Further, if is not added sintering is insufficient and Qu decreases, which is not desired. The addition amount of V 2 O 5 , particularly, from 0.4 to 0.8% by weight is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained. For instance, (1) at the addition amount of from 0.4 to 0.8% by weight (x: 0.8, MnO 2 and PbO: both 0.2% by weight), εr is 44.9 to 46.8, Qu is 1460 to 1950 as τf is -14.5 to -1.7 ppm/°C. and (2) addition amount of 0.6% by weight (x: 0.8, MnO 2 and PbO: both 0.2% by weight), εr is 46.5, Qu is 1430 and τf is -1.75 ppm/°C. and τ f is nearly 0. Further, addition of MnO 2 can increase εr and τf. Since the addition of this ingredient has a function of transferring particularly, τf from negative to positive direction, so that it is effective for adjusting τf from negative to positive direction. On the other hand, if addition amount is more than 1% by weight, Qu tends to decrease remarkably, which it is not preferred. Particularly, the addition amount of MnO 2 from 0.2 to 0.4% by weight (V 2 O 5 ; 0.4% by weight, PbO; 0.2% by weight and x; 0.8) is preferred since this can provide a practical dielectric ceramic composition well balanced in each of the characteristics as εr: 46.8 to 47.9, Qu: 1351 to 1465 and τf: -6.3 to -2.1 ppm/°C. Further, the addition amount of PbO is defined as not more than 0.5% by weight, because Qu and τf decrease greatly if the addition amount is more than 0.5% by weight. Since PbO has an effect of transferring, particularly, τf from positive to negative direction by the addition, it is effect ire for adjusting τf from positive to negative direction. Particularly, the addition amount of PbO from 0.2 to 0.4% by weight (V 2 O 5 : 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8) is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained as εr: 46.8 to 47.4, Qu: 1293 to 1465, τf; -13.2 to -6.3 ppm/°C. Further, it is possible to set the addition amount of V 2 O 5 as 0.3 to 0.8% by weight, the addition amount of MnO 2 as 0.1 to 1.0% by weight, the addition amount of PbO as not more than 0.4% by weight and x as from 0.8 to 0.96, because the performances are well balanced in this case. For instance, it is possible to attain τf; -15 to +4 ppm/°C., Qu: 1000 to 2000 and εr: 44-49. Further, the dielectric ceramic composition of the present invention is produced as described below. The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined at 600°-800° C. to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 850°-950° C. The sintering temperature is defined as within 850° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range. Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter. The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere. In the dielectric ceramic composition according to the present invention, εr, Qu and τf are within a practical characteristic range and each of the characteristics is maintained in a well balanced state. Accordingly, it is suitable to the LC filter material. Further, the dielectric ceramic composition according to the present invention can be prepared by sintering at a relatively low and wide temperature as 850° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing a relation between x and εr in (the main ingredient represented by xBi 2 O 3 -(1-x) (0.8Nb 2 O 5 -0.2Ta 2 O 5 )+0.4% by weight of V 2 O 5 ). FIG. 2 is a graph showing a relation between x and Qu in (a main ingredient represented by xBi 2 O 5 -(1-x) (0.8Nb 2 O 5 -0.2Ta 2 O 5 )+0.4% by weight of V 2 O 5 ). FIG. 3 is a graph showing a relation between x and τf in (the main ingredient represented by xBi 2 O 3 -(1-x) (0.8Nb 2 O 5 -0.2Ta 2 O 5 )+0.4% by weight of V 2 O 5 ). FIG. 4 is a graph showing a relation between y of the main ingredient represented by 0.5Bi 2 O 3 -0.5(yNb 2 O 5 -(1-y) Ta 2 O 5 ) and the addition amount of (α) of V 2 O 5 , and εr. FIG. 5 is a graph showing a relation between y of the main ingredient represented by 0.5Bi 2 O 3 -0.5(yNb 2 O 5 -(1-y) Ta 2 O 5 ) and the addition amount (α) of V 2 O 5 , and Qu. FIG. 6 is a graph showing a relation between y of the main ingredient represented by 0.5Bi 2 O 5 -0.5(yNb 2 O 5 -(1-y) Ta 2 O 5 ) and the addition amount (α) of V 2 O 5 , and τf. FIG. 7 is a graph showing a relation between the sintering temperature and the addition amount (δ) of PbO, and εr in (the main ingredient represented by Bi(Nb 0 .6 Ta 0 .4)O 0 .4)O 4 +0.4% by weight of V 2 O 5 ). FIG. 8 is a graph showing a relation between the sintering temperature and the addition amount (δ) of PbO, and Qu in (the main ingredient represented by Bi(Nb 0 .6 Ta 0 .4)O 4 +0.4% by weight of V 2 O 5 ). FIG. 9 is a graph showing a relation between the sintering temperature and the addition amount (δ) of PhO, and τf in (the main ingredient represented by Bi(Nb 0 .6 Ta 0 .4)O 4 +0.4% by weight of V 2 O 5 ). FIG. 10 is a graph showing a relation between the sintering temperature and the addition amount (δ) of PbO, and the sintering density in (the main ingredient represented by Bi(Nb 0 .6 Ta 0 .4)O 4 +0.4% by weight of V 2 O 5 ). FIG. 11 is a graph showing a relation between the addition amount (δ) of PbO and εr in (the main ingredient represented by Bi(Nb 0 .6 Ta 0 .4)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 12 is a graph showing a relation between the addition amount (δ) of PbO and Qu in (the main ingredient represented by Bi(Nb 0 .6 Ta 0 .4)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 13 is a graph showing a relation between the addition amount (δ) of PbO and τf in (the main ingredient represented by Bi(Nb 0 .6 Ta 0 .4)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 14 is a graph showing a relation between the addition amount (δ) of PbO and the sintering density in (the main ingredient represented by Bi(Nb 0 .6 Ta 0 .4)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 15 is a graph showing a relation between the sintering temperature and the addition amount (β) of MnO 2 , and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 ). FIG. 16 is a graph showing a relation between the sintering temperature and the addition amount (β) of MnO 2 , and Qu in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 ). FIG. 17 is a graph showing a relation between the sintering temperature and the addition amount (β) of MnO 2 , and τf (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2O 5 ). FIG. 18 is a graph showing a relation between the sintering temperature and the addition amount (β) of MnO 2 , and the sintering density in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 ). FIG. 19 is a graph showing a relation between the addition amount (β) of MnO 2 and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 20 is graph showing a relation between the addition amount (β) of MnO 2 and Qu in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 21 is a graph showing a relation between the addition amount (β) of MnO 2 and τf in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 22 is a graph showing a relation between the addition amount (β) of MnO 2 and the sintering density in (the ma in ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 23 is a graph showing a relation between the addition amount (γ) of TiO 2 and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature. FIG. 24 is a graph showing a relation between the addition amount (γ) of TiO 2 and Qu in the ceramic composition and the sintering temperature in FIG. 23. FIG. 25 is a graph showing a relation between the addition amount (γ) of TiO 2 and τf in the ceramic composition and the sintering temperature in FIG. 23. FIG. 26 is a graph showing a relation between the addition amount (γ) of TiO 2 and the sintering density in the ceramic composition and the sintering temperature in FIG. 23. FIG. 27 is a graph showing a relation between the addition amount (α) of V 2 O 5 and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.2% by weight of TiO 2 ) and in case of 900° C. of sintering temperature. FIG. 28 is a graph showing a relation between the addition amount (α) of V 2 O 5 and Qu in the ceramic composition and the sintering temperature in FIG. 27. FIG. 29 is a graph showing a relation between the addition amount (α) of V 2 O 5 and τf in the ceramic composition and the sintering temperature in FIG. 27. FIG. 30 is a graph showing a relation between the addition amount (α) of V 2 O 5 and the sintering density in the ceramic composition and the sintering temperature in FIG. 27. FIG. 31 is a graph showing a relation between x and εr in (the main ingredient represented by Bi(Nbx Ta1-x)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of TiO 2 ) and in case of 900° C. of sintering temperature. FIG. 32 is a graph showing a relation between x and Qu in the ceramic composition and the sintering temperature in FIG. 31. FIG. 33 is a graph showing a relation between x and τf in the ceramic composition and the sintering-temperature in FIG. 31. FIG. 34 is a graph showing a relation between x and the sintering density in the ceramic composition and the sintering temperature in FIG. 31. FIG. 35 is a graph showing a relation between the sintering temperature and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of TiO 2 ). FIG. 36 is a graph showing a relation between the sintering temperature and Qu in the ceramic composition in FIG. 35. FIG. 37 is a graph showing a relation between the sintering temperature and τf in the ceramic composition in FIG. 35. FIG. 38 is a graph showing a relation between the sintering temperature and the sintering density in the ceramic composition in FIG. 35. FIG. 39 is a graph showing a relation between the addition amount (α) of V 2 O 5 and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.2% by weight of MnO 2 +0.2% by weight of TiO 2 (or PbO)) and in case of 900° C. of sintering temperature. FIG. 40 is a graph showing a relation between the addition amount (α) of V 2 O 5 and Qu in the ceramic composition and the sintering temperature in FIG. 39. FIG. 41 is a graph showing a relation between the addition amount (α) of V 2 O 5 and τf in the ceramic composition and the sintering temperature in FIG. 39. FIG. 42 is a graph showing a relation between the addition amount (α) of V 2 O 5 and the sintering density in the ceramic composition and the sintering temperature in FIG. 39. FIG. 43 is a graph showing a relation between the addition amount (β) of MnO 2 and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of TiO 2 (or PbO)) and in case of 900° C. of sintering temperature. FIG. 44 is a graph showing a relation between the addition amount (β) of MnO 2 and Qu in the ceramic composition and the sintering temperature in FIG. 43. FIG. 45 is a graph showing a relation between the addition amount (β) of MnO 2 and τf in the ceramic composition and the sintering temperature in FIG. 43. FIG. 46 is a graph showing a relation between the addition amount (β) of MnO 2 and the sintering density in the ceramic composition and the sintering temperature in FIG. 43. FIG. 47 is a graph showing a relation between the addition amount (γ) of TiO 2 and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of MnO 2 ) and in case of 900 ° C. of sintering temperature. FIG. 48 is a graph showing a relation between the addition amount (γ) of TiO 2 and Qu in the ceramic composition and the sintering temperature in FIG. 47. FIG. 49 is a graph showing a relation between the addition amount (γ) of TiO 2 and τf in the ceramic composition and the sintering temperature in FIG. 47. FIG. 50 is a graph showing a relation between the addition amount (γ) of TiO 2 and the sintering density in the ceramic composition and the sintering temperature in FIG. 47. FIG. 51 is a graph showing a relation between the addition amount (δ) of PbO and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of MnO 2 ) and in case of 900 ° C. of sintering temperature. FIG. 52 is a graph showing a relation between the addition amount (δ) of PhO and Qu in the ceramic composition and the sintering temperature in FIG. 51. FIG. 53 is a graph showing a relation between the addition amount (δ) of PbO and τf in the ceramic composition and the sintering temperature in FIG. 51. FIG. 54 is a graph showing a relation between the addition amount (δ) of PbO and the sintering density in the ceramic composition and the sintering temperature in FIG. 51. FIG. 55 is a graph showing a relation between x and εr in (the main ingredient represented by Bi(Nbx Ta1-x)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of MnO 2 +0.2% by weight of TiO 2 (or PhO)) and in case of 900° C. of sintering temperature. FIG. 56 is a graph showing a relation between x and Qu in the ceramic composition and the sintering temperature in FIG. 55. FIG. 57 is a graph showing a relation between x and τf in the ceramic composition and the sintering temperature in FIG. 55. FIG. 58 is a graph showing a relation between x and the sintering density in the ceramic composition and the sintering temperature in FIG. 55. FIG. 59 is a graph showing a relation between the sintering temperature and εr in (the main ingredient represented by Bi(Nb 0 .8 Ta 0 .2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of MnO 2 +0.2% by weight of TiO 2 (or PbO)). FIG. 60 is a graph showing a relation between the sintering temperature and Qu in the ceramic composition in FIG. 59. FIG. 61 is a graph showing a relation between the sintering temperature and τf in the ceramic composition in FIG. 59. FIG. 62 is a graph showing a relation between the sintering temperature and the sintering density in the ceramic composition in FIG. 59. DETAILED DESCRIPTION OF THE INVENTION EXAMPLES The present invention will be explained more specifically by way of examples. Example 1 Bi 2 O 3 a powder (purity: 98.9%), Nb 2 O 5 powder (purity: 99.9%), Ta 2 O 5 powder (purity: 99.9%) and V 2 O 5 powder (purity: 99.5%) were used as the raw material, and they are weighed and mixed each by a predetermined amount (about 600 g as the entire amount in each of the cases) so as to provide compositions in which x ranges from 0.43 to 0.57 and each of y and the addition amount of V 2 O 5 (α% by weight) varies within a range of 0 to 1.0 in xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ) as shown in Tables 1 and 2. Subsequently, the weighed and mixed raw material powders were applied with primary pulverization by a vibration mill (3 hours) and then calcined in an ambient atmosphere at 700° C. for 2 hours. Then, an appropriate amount of an organic binder (15 g) and water (320 g) were added to each calcined powder and applied with secondary pulverization was conducted in a ball mill using alumina balls of 20 mmφ, at 90 rpm for 23 hours. Subsequently, they were pelletized by vacuum freeze drying (pressure: about 0.4 Torr, freezing temperature: -20° to -40° C., drying temperature: 40° to 50° C., drying time: about 20 hours). The thus pelletized raw materials were molded at a pressure of 1 ton/cm 2 to obtain cylindrical molding products each of 19 mmφ×10 mmt (height). TABLE 1______________________________________[0.5Bi.sub.2 O.sub.3 - 0.5 {yNb.sub.2 O.sub.5 - (1 - y) Ta.sub.2 O.sub.5} +αV.sub.2 O.sub.5] ceramic composition Rel. α dielect. (V.sub.2 O.sub.5) f.sub.o const. τ.sub.fNo. y (wt %) (GHz) ε.sub.r Qu (ppm/°C.)______________________________________1 0.2 0.2 4.4 33.2 703 -56.82 0.4 0.2 4.0 42.5 510 -49.03 0.6 0.2 3.9 43.5 443 -41.24 0.8 0.2 3.9 43.1 491 -28.05 0.2 0.4 3.9 44.7 1344 -53.16 0.4 0.4 3.9 45.9 1488 -46.47 0.6 0.4 3.8 46.2 1305 -32.88 0.8 0.4 3.9 44.6 1487 -18.59 0.2 0.6 3.8 47.1 1014 -52.110 0.4 0.6 3.8 47.7 897 -39.811 0.6 0.6 3.8 46.6 791 -29.612 0.8 0.6 3.9 45.6 816 -18.513 0.2 0.8 3.7 49.0 746 -51.114 0.4 0.8 3.7 49.0 590 -36.215 0.6 0.8 3.8 48.0 505 -25.016 0.8 0.8 3.9 45.7 598 -18.9______________________________________ TABLE 2______________________________________[xBi.sub.2 O.sub.3 - (1 - x) {yNb.sub.2 O.sub.5 - (1 - y)Ta.sub.2 O.sub.5 } + αV.sub.2 O.sub.5] ceramic composition Rel. α dielect. (V.sub.2 O.sub.5) f.sub.o const. τ.sub.fNo. x y (wt %) (GHz) ε.sub.r Qu (ppm/°C.)______________________________________17 0.43 0.8 0.4 4.0 41.6 243 -26.518 0.45 0.8 0.4 4.0 42.2 610 -18.019 0.47 0.8 0.4 4.0 42.9 1100 -16.220 0.49 0.8 0.4 3.9 44.0 1360 -17.321 0.51 0.8 0.4 3.9 45.0 1432 -23.122 0.53 0.8 0.4 3.9 44.8 1190 -27.023 0.55 0.8 0.4 4.0 43.9 780 -31.524 0.57 0.8 0.4 4.0 42.7 370 -38.025 0.5 0 0.2 4.6 30.8 829 -57.526 0.5 0 0.4 4.1 40.4 1115 -48.327 0.5 0 1.0 3.7 50.3 562 -36.528 0.5 1.0 0.2 4.1 42.3 476 -23.629 0.5 0.9 0.4 4.0 43.7 1450 -11.530 0.5 1.0 0.4 4.0 42.9 1504 -2.731 0.5 1.0 1.0 4.0 44.5 557 -6.232 0.5 0.4 0 4.9 29.8 203 -68.0______________________________________ Then, the molding products were degreased in an atmospheric air at 500° C. for 3 hours and then sintered at 850° to 900° C. for 2 hours to obtain sintering products. Finally, each of the sintering products was polished at both end faces into a cylindrical shape of about 16 mmφ×8 mmt (height), further cleaned with a diluted solution comprising 5 parts of an aqueous detergent ("Eriese K-2000" manufactured by Asahi Kasei Co.) and 100 parts of water mixed together, at 23° C. for 60 min, and dried at 80° C. for 10 hours to form dielectric specimens (Nos. 1-32 in Tables 1 and 2). The temperature elevation rate was 200° C./h and the temperature lowering rate was -200° C./h in the calcining step, the temperature elevation rate was 50° C./h in the decreasing step, and the temperature elevation rate was 100° C./h and the temperature lowering rate was -100° C./h in the sintering step. Then, εr, Qu and τf were measured for each of the specimens by a parallel conductor plate dielectric columnar resonator method (TE 011 MODE) or the like. The resonance frequency upon measurement is as shown in Table 1 (f 0 ). Further, τf was measured at a temperature region from 23° to 80° C. and calculated according τf=(f 80 -f 23 )/(f 23 ×ΔT) and ΔT=80-23=57° C. The results are shown in Tables 1 and 2 and in the graphs of FIGS. 1 to 6. From the results, Qu decreases remarkably at x for 0.43 and 0.57 and εr also decreases considerably at x for 0.43 (No. 17 in Table 2) and τf also decreases in the negative direction at x for 0.57 (No. 24 in Table 2). On the other hand it can seen that within a range of x from 0.45 to 0.55, particularly, from 0.47 to 0.51, compositions excellent in all of εr, Qu and τf and well balanced in the characteristics is obtained (FIGS. 1-3). Further, εr slightly decrease at y=1.0 and at a of 0.2% by weight (No. 28 in Table 2) and 0.4% by weight (No. 30 in Table 2) as compared with a case of y at 0.2 to 0.8. And if y is 0.9 and α is 0.4% by weight (No. 29 in Table 2), balance of εr, Qu and τf is excellent. If y is 0, εr decreases further. Further, if y is 0, and α is 1.0 % by weight (No. 27 in Table 2), although εr is excellent, Qu tends to decrease. Further, if y is 1.0, and αis 1.0% by weight (No. 31 in Table 2), although τf is excellent, Qu decreases. If y is 0.4 and α is 0 (No. 32 in Table 2), all εr, Qu and τf greatly decrease because sintering is insufficient (FIGS. 4-6). In each of the examples described above, although each of the performances εr, Qu and τf is excellent individually, balance between each of them is somewhat poor. On the other hand, if y is in a range of 0.2 to 0.8 and α is 0.8 % by weight (Nos. 13-16 in Table 1) and 0.6 by weight (Nos 9-12 in Table 1), εr is excellent. Although Qu decreases if α is 0.8% by weight but it is within a range causing no practical problem. Further, τf also exhibits a practically sufficient performance with no problem. Further, if y is within a range from 0.2 to 0.8 and α is 0.4 % by weight (Nos. 5 to 8 in Table 1), although εr tends to decrease slightly as compared with the case of α at 0.8 % and 0.6% by weight, Qu is improved greatly and τf is equivalent, to show well balanced excellent performance. Furthermore, if y is within a range from 0.2 to 0.8 and a is 0.2% by weight (Nos. 1-4 in Table 1), each of the characteristics tends to decrease as compared with the case of greater α, but they are within a practically sufficient range (FIGS. 4 to 6). In particular, as shown in results of tables 1 and 2, it is preferred that x is from 0.47 to 0.53, y is from 0.4 to 0.8 and α is from 0.4 to 0.6, since each physical property is balanced. In this case, εr may be from 42.9 to 47.7, Qu may be from 790 to 1490 and τf may be from -46.4 to -16.2 ppm/°C. Further, it can be seen from FIGS. 4 to 6, that each of the characteristics exhibits a substantially identical trend as y increases from 0.2 to 0.8 irrespective of the value α and, particularly, the performance τf tends to be improved, and the value rf can be controlled within a practical value while maintaining high εr and Qu with no practical problem, by varying the ratio of Nb 2 O 5 and Ta 2 O 5 . Example 2 As the raw material in this example, PbO powder (purity: 99.5%) was added further to each of the powder used in Example 1. Then, the starting materials were weighed and mixed in the same manner as in Example 1 so as to obtain a composition in which x is 0.6, the addition amount of V 2 O 5 is 0.4% by weight and the addition amount of PbO (δ% by weight) varies within a range from 0 to 2.0 in Bi(NbxTa1-x)O 4 as shown in Table 3. In Table 3, x is 0.2 in No. 13, an addition amount of V 2 O 5 is 3.0% by weight in No. 14, and x is 0.2 and an addition amount of V 2 O 5 is 3.0% by weight in No. 15. Further, in the same manner as in Example 1, dielectric specimens of identical shape (Nos. 1 to 30 in Table 3) were obtained and performance evaluation (εr, Qu, τf and sintering density) was carried out. The results are also shown in Table 3 and shown in the graphs of FIGS. 7 to 14. The sintering products were cleaned after polishing at 80° C. for 30 min and then dried subsequently at 100° C. for 4 hours. The resonance frequency upon measurement is as shown in Table 3 (f 0 ). τf was measured within a temperature region of 25° to 80° C. and calculated according to τf=(f 80 -f 25 )/(f 25 ×ΔT), and ΔT=80-25=55° C. TABLE 3__________________________________________________________________________ Sinter. V.sub.2 O.sub.5 PbO Sint. temp. (α) (δ) f.sub.o τ.sub.f densityNo. (°C.) x (wt %) (wt %) (GHz) ε.sub.r Qu (ppm/°C.) (g/cm.sup.3)__________________________________________________________________________1 850 0.6 0.4 0 Resonance wave form is 6.81 very weak.2 0.6 0.4 0.2 3.98 42.05 1425 -42.10 7.493 0.6 0.4 0.4 3.83 46.19 1041 -47.22 7.864 0.6 0.4 1 3.83 46.08 487 -58.78 7.705 0.6 0.4 2 3.75 48.06 193 -60.38 7.726 875 0.6 0.4 0 3.85 44.08 1607 -35.91 7.707 0.6 0.4 0.2 3.85 45.43 1640 -39.18 7.798 0.6 0.4 0.4 3.82 46.53 1213 -47.32 7.899 0.6 0.4 1 3.75 48.33 482 -53.06 7.9110 0.6 0.4 2 3.67 50.38 238 -73.80 7.9111 900 0.6 0.4 0 3.85 46.19 1304 -32.82 7.9012 0.6 0.4 0.2 3.83 46.21 1528 -36.67 7.8513 0.2 0.4 0.2 3.85 45.01 1511 -48.21 8.0514 0.6 3.0 0.2 3.80 46.71 735 -42.33 7.9515 0.2 3.0 0.2 3.83 46.40 594 -53.03 8.2316 0.6 0.4 0.4 3.83 46.94 1211 -43.50 7.8917 0.6 0.4 0.6 3.81 47.46 956 -47.80 7.9018 0.6 0.4 0.7 3.80 47.71 828 -49.90 7.9119 0.6 0.4 1 3.76 48.48 445 -56.27 7.9320 0.6 0.4 2 3.65 51.37 280 -83.01 7.9621 925 0.6 0.4 0 3.84 45.93 1255 -31.78 7.6722 0.6 0.4 0.2 3.82 46.36 1423 -39.76 7.8823 0.6 0.4 0.4 3.82 46.58 1192 -45.64 7.8724 0.6 0.4 1 3.75 48.52 458 -56.87 7.9225 0.6 0.4 2 3.64 51.45 240 -104.80 7.9826 950 0.6 0.4 0 3.87 44.87 1214 -33.01 7.6527 0.6 0.4 0.2 3.81 46.16 1378 -39.12 7.8428 0.6 0.4 0.4 3.82 46.46 1094 -44.83 7.8529 0.6 0.4 1 3.75 48.53 407 - 62.61 7.9130 0.6 0.4 2 3.63 51.69 214 106.00 7.97__________________________________________________________________________ From the results, εr is improved from about 45 to about 51 along with increase in the addition amount of PbO irrespective of the sintering temperature except for a case of 42.05 at a sintering temperature of 850° C. and the addition amount of PbO of 0.2% by weight (FIGS. 7 and 11). Improvement of Qu is observed if PbO is added by 0.2% by weight at each of sintering temperature as compared with the case of no addition, but it tends to decrease as the addition amount increases and, particularly, Qu decreases greatly at the addition amount of 1 to 2% by weight (the trend is shown clearly in FIGS. 8 and 12). Further, τf tends to increase toward the negative direction along with increase in the addition amount of PbO and the trend is particularly remarkable at the addition amount of 2% by weight (the trend is shown clearly in FIGS. 9 and 13). From abovementioned results, it is preferred that x is from 0.2 to 0.9 (tables 1 and 2), the addition amount of V 2 O 5 is from 0.2 to 2.0 part by weight and the addition amount of PbO is from 0.2 to 0.6% by weight (table 3). In this case, εr may be from 45 to 48, Qu may be from 960 to 1640 (at from 3.6 to 4.0 GHz) and τf may be from -47 to -32 ppm/°C. On the other hand, the sintering density takes a particularly small value in a case where PhO is not added and the sintering temperature is as low as 850° C. In other cases, it slightly increases at each of the sintering temperatures along with the increase in the addition amount of PbO except for a certain case but no remarkable change is observed as a whole (it can be seen also in FIGS. 10 and 14) As described above, while each of the characteristics varies in accordance with the addition amount of PbO and the sintering temperature, each of the characteristics is within a range of causing no practical problem so long as they are within the range of the present invention. As a whole, it can he seen that most practically preferred dielectric ceramic compositions are obtained at a sintering temperature of 875° C. or 900° C., with the addition amount of PbO of 0.2 or 0.4% by weight since each of the characteristic is balanced most satisfactorily. Further, as can be seen from the results of Nos. 13 to 15, τf tends to increase toward the negative direction if x is as small as 0.2 in the present invention, but dielectric ceramic compositions of excellent characteristics can be obtained according to the present invention within a wide range for x and the addition amount of V 2 O 5 . Example 3 For the raw material in this example, MnO 2 powder (purity: 96.0%) was used instead of the PbO powder used in Example 2. Then, the raw materials were weighed and mixed in the same manner as in Example 2 so as to obtain compositions in which x Bi(NbxTa 1 -x)O 4 is 0.8, the addition amount of V 2 O 5 is 0.4% by weight and the addition amount of MnO 2 (β% by weight) ranges range from 0 to 2.0. In Table x is 0.2 in 4, No. 14, addition amount of V 2 O 5 is 3.0% by weight in No. 15, and x is 0.2 and addition amount of V 2 O 5 is 0.3% by weight in No. 16 in Table 4. TABLE 4__________________________________________________________________________ Sinter. V.sub.2 O.sub.5 MnO.sub.2 Sint. temp. (α) (β) f.sub.o τ.sub.f densityNo. (°C.) x (wt %) (wt %) (GHz) ε.sub.r Qu (ppm/°C.) (g/cm.sup.3)__________________________________________________________________________1 850 0.8 0.4 0 Resonance wave form is 7.08 very weak.2 0.8 0.4 0.2 3.84 45.85 1640 -11.61 7.523 0.8 0.4 0.4 3.81 46.83 1176 -9.76 7.524 0.8 0.4 1 3.75 48.62 715 -7.84 7.515 0.8 0.4 2 3.66 50.99 433 -5.50 7.486 875 0.8 0.4 0 3.86 44.45 1757 -18.73 7.477 0.8 0.4 0.2 3.84 46.01 1684 -11.75 7.528 0.8 0.4 0.4 3.82 46.93 1223 -9.91 7.539 0.8 0.4 1 3.75 48.71 729 -10.09 7.5110 0.8 0.4 2 3.65 51.25 449 -8.31 7.4811 900 0.8 0.4 0 3.92 44.60 1485 -18.47 7.4812 0.8 0.4 0.1 3.89 45.17 1574 -14.32 7.4913 0.8 0.4 0.2 3.86 45.74 1662 -10.16 7.5014 0.2 0.4 0.2 3.88 44.72 1482 -53.10 8.1315 0.8 3.0 0.2 3.82 46.31 681 -12.13 7.5516 0.2 3.0 0.2 3.86 45.81 721 -62.31 8.2417 0.8 0.4 0.4 3.83 46.85 1202 -8.34 7.5118 0.8 0.4 0.6 3.80 47.40 1046 -7.81 7.5019 0.8 0.4 0.7 3.79 47.68 968 -7.55 7.5020 0.8 0.4 1 3.75 48.50 734 -6.76 7.4921 0.8 0.4 2 3.65 51.45 476 -8.53 7.4722 925 0.8 0.4 0 3.91 44.78 1319 -19.47 7.3723 0.8 0.4 0.2 3.88 45.12 1680 -11.70 7.4624 0.8 0.4 0.4 3.84 46.37 1163 -8.43 7.4625 0.8 0.4 1 3.77 48.18 721 -9.38 7.4426 0.8 0.4 2 3.65 51.02 445 -10.60 7.4427 950 0.8 0.4 0 3.94 43.75 1245 -19.76 7.2528 0.8 0.4 0.2 3.91 44.09 1668 -13.33 7.3929 0.8 0.4 0.4 3.87 45.35 1181 -10.37 7.3930 0.8 0.4 1 3.80 46.95 710 -9.26 7.3531 0.8 0.4 2 3.67 50.50 418 -12.50 7.35__________________________________________________________________________ Further, in the same manner as in Example 2, dielectric specimens of identical shape (Nos. 1 to 31 in Table 4) were obtained and performance evaluation (εr, Qu, τf and sintering density) was carried out. The resonance frequency upon measurement was as shown in Table 5 (f 0 ). The results are shown together in Table 4 and a 1 so shown in the graphs of FIGS. 15 to 22. According to the results, τf is extremely poor in a case of not adding MnO 2 and it is improved greatly by the addition of MnO 2 by 0.2% by weight. However, although τf tends to the improve a slightly with further increase of the addition amount but shows no great change (in FIG. 17, a curve at β=0 is much different from others, and other curves show no so great difference. This can be seen clearly also in FIG. 21). Further, εr is improved from about 45 to about 51 along with increase in the addition amount of MnO 2 irrespective of the sintering temperature (FIGS. 15 and 19). Further, although Qu tends to decrease along with increase in the addition amount of MnO 2 in a lower sintering temperature, it reaches a peak at the addition amount of 0.2% by weight as the sintering temperature goes higher and subsequently decreases along with increase the addition amount of MnO 2 (in FIG. 16, curves for β and β=0.2 intersect with each other between 875° C. and 900° C. and Qu at β=0.2 is higher in a high temperature region higher than 900° C. Further, such a trend is also shown in FIG. 20 for the sintering temperature at 900° C.). From abovementioned results, it is preferred that x is from 0.2 to 0.9 (table 1 and 2), the addition amount of V 2 O 5 is from 0.2 to 2.0 part by weight (table 4) and the addition amount of MnO 2 is from 0.1 to 0.6 wt % (table 4). In this case, εr may be from 45 to 47, Qu may be from 970 to 1640 (at from 3.6 to 3.9 GHz) and τf may be from -14 to -5.5 ppm/°C. On the other hand, the sintering density takes a particularly small value if MnO 2 is not added and the sintering temperature is as low as 850° C. In other cases where the sintering temperature is high, the sintering density is improve slightly by the addition amount of MnO 2 of 0.2% by weight at a higher sintering temperature and no remarkable changes is observed with addition amount of MnO 2 . Further, the sintering density tends to lower as a whole, as the sintering temperature goes higher (this is shown clearly in FIGS. 18 and 22). In this way, each of the characteristics changes variously along with the addition amount of MnO 2 and the sintering temperature, but each of the characteristics lies within a range of causing no practical problem so long as they are within a range of the present invention. It can be seen as a whole, that preferred dielectric ceramic compositions well balanced in each of the characteristics can be obtained, particularly, at a sintering temperature of 875° C. or 900° C. and with the addition amount of MnO 2 of 0.2 or 0.4 by weight. Further, as can be seen from the results of Nos. 14 to 16, τf tends to increase toward the negative direction if x is as small as 0.2 in the present invention, but dielectric ceramic compositions having practically sufficient characteristics can be obtained in a wide range for x and the addition amount of V 2 O 5 . Example 4 For the raw material in this example, TiO 2 powder (purity: 99.9%) was used instead of the PbO powder used in Example 2. Then, the starting materials were weighed and mixed in the same manner as in Example 2 so as to obtain a composition in which x in Bi(NbxTa1-x)O4 ranges from 0 to 1.0, the addition amount of V 2 O 5 (α% by weight) ranges from 0 to 3.0 and the addition amount of TiO 2 (τ% by weight) ranges from 0 to 2.0. Further, dielectric specimens of identical shape were prepared in same manner as Example 2 (Nos. 1 to 23 in Table 5) and performance evaluation (εr, Qu, τf and sintering density) was carried out. The resonance frequency upon measurement was as shown in Table 5 (f 0 ). The results are shown together in Table 5 and also shown in the graphs of FIGS. 23 to 38. TABLE 5__________________________________________________________________________ Sinter. V.sub.2 O.sub.5 TiO.sub.2 Sint. temp. (α) (γ) f.sub.o τ.sub.f densityNo. (°C.) x (wt %) (wt %) (GHz) ε.sub.r Qu (ppm/°C.) (g/cm.sup.3)__________________________________________________________________________1 900 0.8 0.4 0 3.92 44.60 1485 -18.47 7.482 900 0.8 0.4 0.1 3.40 45.92 1155 -15.81 7.493 900 0.8 0.4 0.2 3.45 47.06 865 -12.24 7.514 900 0.8 0.4 0.4 3.38 47.48 678 -8.96 7.435 900 0.8 0.4 0.6 3.47 46.33 598 -2.38 7.236 900 0.8 0.4 1.0 3.52 43.37 371 10.61 6.897 900 0.8 0.4 2.0 3.54 37.39 251 53.78 6.898 850 0.8 0.4 0.2 Sintering is insufficient.9 875 0.8 0.4 0.2 3.89 45.43 909 -12.27 7.3610 925 0.8 0.4 0.2 3.40 47.16 838 -10.81 7.5211 950 0.8 0.4 0.2 3.53 47.70 785 -11.76 7.5212 900 0.8 0 0.2 Sintering is insufficient.13 900 0.8 0.2 0.2 3.47 46.73 839 -13.55 7.5014 900 0.8 1.0 0.2 3.35 47.62 613 -5.51 7.5515 900 0.8 2.0 0.2 3.48 48.18 318 -13.94 7.5316 900 0.8 3.0 0.2 3.60 49.01 185 -21.63 7.5417 900 0 0.4 0.2 3.59 42.03 553 -52.13 8.0818 900 0.2 0.4 0.2 3.53 44.54 512 -55.21 8.1119 900 0.4 0.4 0.2 3.48 46.44 631 -48.03 8.0520 900 0.6 0.4 0.2 3.41 47.21 725 -30.12 7.9021 900 0.7 0.4 0.2 3.43 47.13 795 -21.18 7.7022 900 0.96 0.4 0.2 3.45 46.11 1010 -0.11 7.1523 900 1.0 0.4 0.2 3.23 45.86 1050 2.01 7.05__________________________________________________________________________ The results show that τf improves greatly along with the addition amount of TiO 2 and τf can be controlled easily (FIG. 25). However, since εr and Qu decrease along with addition of TiO 2 (FIGS. 23 and 24), addition of a great amount of TiO 2 is not preferred. Further, if V 2 O 5 is not added (No. 12), the sintering is insufficient and measurement for each of the characteristics is impossible. Then, since εr increases (FIG. 27) and τf decreases (FIG. 29) by the addition, τf can be controlled. However, since Qu decreases by the addition (FIG. 28), addition of a great amount of V 2 O 5 is not preferred. Further, since τf increases along with increase for the value x in Bi(NbxTa1-x)O 4 (FIG. 33), τf can be controlled by the change of the value x. Further, since εr and Qu also increase along with this increase (FIGS. 31 and 32), although it is preferred in view of this physical property, the sintering density is lowered (FIG. 34). 7.0 kg/m 3 of sintering density can be ensured even if x is 1.0 (FIG. 34). Further, if the sintering temperature is at 850° C. (No. 8 in Table 5), sintering is insufficient and measurement for each of the characteristics is impossible. On the other hand, at 875° to 950° C. (x=0.8, V 2 O 5 =0.4% by weight, TiO 2 =0.2% by weight), the sintering density is as large as 7.36 to 7.52 kg/m 3 (FIG. 38) and the physical properties is are also stable (FIGS. 35-37). As described above, while each of the physical properties changes variously in accordance with the addition amounts of V 2 O 5 and TiO 2 and the sintering temperature, each of the characteristics lies within a range causing no practical problem so long as they are within a range of the present invention. For instance, in a case where x=0.6 to 0.96, V 2 O 5 =0.2 to 1.0% by weight and TiO 2 =0.1 to 0.6% by weight, τf=-30 to 0 ppm/°C., Qu=610 to 1160, εr=42 to 48. In a case where x=0.8 to 0.96, V 2 O 5 =0.4 to 1.0% by weight and TiO 2 =0.2 to 1.0% by weight, εr=43.3 to 47.7, Qu=370 to 910, τf=-13 to +11 ppm/°C. Particularly, in a case where x=0.8, V 2 O 5 is 0.4% by weight, TiO 2 =0.2 to 0.4% by weight, εr=45.4 to 47.7, Qu=510 to 910 and τf=-13 to -9 ppm/°C., showing excellent balance of performance. As can be seen from the results of Nos. 18 to 20 in Table 5, although τf tends to increase toward the negative direction (-55 to -30 ppm/°C.) if x=as small as 0.2 to 0.6 in the present invention, εr is from 42.0 to 47.2 and Qu is from 510 to 730, which are practically sufficient characteristics. Example 5 (1) Preparation of dielectric ceramic composition As the raw material in this example, TiO 2 powder (purity: 99.9%) or PbO powder (purity: 99.5%) was further used in addition to the powder used in Example 3. Then, the raw materials were weighted and mixed in the same manner as in Example 3 so as to obtain a composition in which x in Bi(NbxTa1-x)O 4 varies from 0 to 1.0, the addition amount of V 2 O 5 (α% by weight) varies from 0 to 3.0, the addition amount of MnO 2 (β% by weight) varies from 0 to 2.0 and the addition amount of TiO 2 (γ% by weight, shown in Table 6) varies from 0 to 2.0 and, further, the addition amount of PbO (δ% by weight, shown in Table 7) varies from 0 to 2.0, as shown in Table 6 and 7. Further, in the same manner as in Example 3, dielectric specimens of identical shape (Nos. 1 to 27 in Table 6 and Nos. 1 to 29 in Table 7) were obtained and performance evaluation (εr, Qu, τf and sintering density) was carried out. The resonance frequency upon measurement was as shown in Tables 6 and 7 (f 0 ). The results are shown together in Tables 6 and 7 and also shown in the graphs of FIGS. 39 to 62. (2) Effect of examples in V 2 O 5 --MnO 2 --TiO 2 system composition According to the results of Table 6 and FIGS. 39-50 and FIGS. 55 to 62, if V 2 O 5 is not added (No. 12 in Table 6) sintering is insufficient and measurement for each of the characteristics is impossible. Then, since εr increases (FIG. 39) and τf decreases (FIGS. 41) along with addition, τf can be controlled. However, since Qu decreases along with addition (FIG. 40), addition of a great amount of V 2 O 5 is not preferred. TABLE 6__________________________________________________________________________ Sinter. α β γ Sint. temp. (V.sub.2 O.sub.5) (MnO.sub.2) (TiO.sub.2) f.sub.o τ.sub.f densityNo. (°C.) x (wt %) (wt %) (wt %) (GHz) ε.sub.r Qu (ppm/°C.) (g/cm.sup.3)__________________________________________________________________________1 900 0.8 0.4 0.2 0 3.86 45.74 1662 -10.16 7.502 900 0.8 0.4 0.2 0.1 3.40 46.40 1493 -8.81 7.513 900 0.8 0.4 0.2 0.2 3.35 47.06 1325 -7.46 7.534 900 0.8 0.4 0.2 0.4 3.38 48.57 747 -1.17 7.505 900 0.8 0.4 0.2 0.7 3.36 48.91 632 6.48 7.366 900 0.8 0.4 0.2 1.0 3.24 49.25 517 14.13 7.227 900 0.8 0.4 0.2 2.0 3.42 46.81 255 50.22 6.678 850 0.8 0.4 0.2 0.2 3.15 46.33 1618 -6.59 7.309 875 0.8 0.4 0.2 0.2 3.19 46.92 1461 -6.78 7.5210 925 0.8 0.4 0.2 0.2 3.33 46.94 1319 -6.30 7.5211 950 0.8 0.4 0.2 0.2 3.31 47.20 1282 -5.44 7.5112 900 0.8 0 0.2 0.2 Sintering is insufficient.13 900 0.8 0.2 0.2 0.2 3.41 46.63 1227 -10.91 7.5014 900 0.8 1.0 0.2 0.2 3.35 47.88 893 -2.45 7.5615 900 0.8 2.0 0.2 0.2 3.43 48.91 598 -9.03 7.5016 900 0.8 3.0 0.2 0.2 3.41 49.04 417 -16.79 7.4517 900 0.8 0.4 0 0.2 3.45 47.06 865 -12.24 7.5118 900 0.8 0.4 0.4 0.2 3.31 47.23 1438 -6.03 7.5019 900 0.8 0.4 1.0 0.2 3.44 47.46 903 -11.10 7.5020 900 0.8 0.4 1.5 0.2 3.41 47.18 760 -11.46 7.4621 900 0.8 0.4 2.0 0.2 3.40 46.89 618 -11.83 7.4122 900 0 0.4 0.2 0.2 3.31 44.18 884 -48.23 8.0823 900 0.2 0.4 0.2 0.2 3.24 45.90 1023 -49.58 8.1324 900 0.4 0.4 0.2 0.2 3.43 47.16 1211 -44.35 7.9825 900 0.6 0.4 0.2 0.2 3.41 47.51 1203 -25.11 7.7326 900 0.96 0.4 0.2 0.2 3.27 46.02 1389 3.51 7.2127 900 1.0 0.4 0.2 0.2 3.40 45.74 1415 6.34 7.05__________________________________________________________________________ TABLE 7__________________________________________________________________________ Sinter. α β δ Sint. temp. (V.sub.2 O.sub.5) (MnO.sub.2) (PbO) f.sub.o τ.sub.f densityNo. (°C.) x (wt %) (wt %) (wt %) (GHz) ε.sub.r Qu (ppm/°C.) (g/cm.sup.3)__________________________________________________________________________1 900 0.8 0 0.2 0.2 Sintering is insufficient.2 900 0.8 0.2 0.2 0.2 3.45 47.80 641 -12.90 7.573 900 0.8 0.3 0.2 0.2 3.44 47.30 1050 -9.60 7.554 900 0.8 0.4 0.2 0.2 3.47 46.81 1465 -6.28 7.535 900 0.8 0.6 0.2 0.2 3.42 46.53 1430 -1.75 7.516 900 0.8 0.8 0.2 0.2 3.47 44.88 1952 -14.46 7.467 900 0.8 1.0 0.2 0.2 3.45 43.75 1842 -23.14 7.428 900 0.8 2.0 0.2 0.2 3.46 42.49 1204 -35.03 7.359 900 0.8 3.0 0.2 0.2 3.40 41.80 513 -44.12 7.4010 850 0.8 0.4 0.2 0.2 3.50 46.98 1523 -16.24 7.4811 875 0.8 0.4 0.2 0.2 3.39 47.13 1468 -11.74 7.5512 925 0.8 0.4 0.2 0.2 3.48 46.89 1388 -13.43 7.5013 950 0.8 0.4 0.2 0.2 3.45 47.04 1399 -10.02 7.5214 900 0.8 0.4 0 0.2 3.40 45.35 1604 -18.04 7.5015 900 0.8 0.4 0.1 0.2 3.46 46.58 1520 -15.47 7.5316 900 0.8 0.4 0.4 0.2 3.35 47.86 1351 -2.07 7.5217 900 0.8 0.4 1.0 0.2 3.46 48.51 1047 -5.34 7.5018 900 0.8 0.4 2.0 0.2 3.45 49.10 798 -12.95 7.5319 900 0.8 0.4 0.2 0 3.86 45.74 1662 -10.16 7.5020 900 0.8 0.4 0.2 0.4 3.65 47.39 1293 -13.24 7.4921 900 0.8 0.4 0.2 0.5 3.36 47.42 1203 -15.70 7.4922 900 0.8 0.4 0.2 1.0 3.54 48.48 753 -28.00 7.4823 900 0.8 0.4 0.2 2.0 3.32 49.25 490 -49.57 7.4524 900 0 0.4 0.2 0.2 3.45 43.81 1050 -44.03 8.0725 900 0.2 0.4 0.2 0.2 3.41 45.99 1223 -48.15 8.0926 900 0.4 0.4 0.2 0.2 3.40 46.75 1335 -39.95 8.0027 900 0.6 0.4 0.2 0.2 3.47 47.01 1421 -23.42 7.7528 900 0.96 0.4 0.2 0.2 3.40 45.89 1503 3.98 7.1229 900 1.0 0.4 0.2 0.2 3.49 45.50 1530 5.15 7.04__________________________________________________________________________ Further, since Qu increases along with addition of MnO 2 up to 0.4% by weight, the addition is effective, but addition of a great amount (1 and 2% by weight) is not preferred because Qu decreases greatly (FIG. 43). It is shown that τf is improved greatly by addition of TiO 2 and τf can be controlled easily (FIG. 49) Further, addition of TiO 2 up to 1.0% by weight is preferred since εr increases (FIG. 47). Further, since Qu decreases by the addition of TiO 2 and, particularly, Qu decreases remarkably as 747 at 0.4% by weight, addition of a great amount of TiO 2 is not preferred (FIG. 48). Further, since τf increases along with increase of the value x in Bi(NbxTa1-x)O 4 (FIG. 57), τf can be controlled by the change of the x. Further, since Qu increases along with increase of x (FIG. 56) and εr also increases with x up to 0.6 (FIG. 55), it is preferred in view of this physical property, but the sintering density is lowered (FIG. 58). Further, 7.05 kg/m 3 of the sintering density can be insured even if x is 1.0 (No. 27, FIG. 58). Further, sintering is sufficient even at a sintering temperature of 850° C. (No. 8 in Table 6) and the sintering density is as great as 7.30 to 7.51 kg/m 3 at 850°-950° C. (x=0.8, V 2 O 5 =0.4% by weight, MnO 2 =0.2% by weight and TiO 2 =0.2% by weight) (Nos. 8 to 11 in Table 6, FIG. 62), and physical properties are also stable (FIGS. 59 to 62). As described above, each of the characteristics changes variously in accordance with the kind of each of the additives, the addition amount thereof and the sintering temperature and well balanced practical performances as shown below are given, for example, with the range of the following compositions according to the results of this example (Table 6). (1) At V 2 O 5 : 0.2 to 1.0% by weight, Mn 2 , TiO 2 : both 0.2% by weight and x: 0.8, εr: 46.6 to 47.9, Qu: 890 to 1300, τf: -10.91 to -2.45 ppm/°C. (2) At V 2 O 5 : 0.4% by weight, MnO 2 , TiO 2 : both 0.2% by weight and x: 0.8, εr: 47.1, Qu: 1325, τf: -7.46 ppm/°C. (3) At MnO 2 : 0.2-1.0% by weight, V 2 O 5 : 0.4% by weight, TiO 2 : 0.2% by weight and x: 0.8, εr: 47.0 to 47.5, Qu: 900 to 1440, τf: -11.1 to -6.0 ppm/°C. (4) At TiO 2 : less than 0.4% by weight, V 2 O 5 : 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8, εr: 45.7 to 48.6, Qu: 750 to 1660, τf: -10.2 to -1.1 ppm/°C. (5) At TiO 2 : 0.1 to 0.2% by weight, V 2 O 5 : 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8, εr: 46.4 to 47.1, Qu: 1320 to 1490, τf: -8.8 to -7.5 ppm/°C. (6) At V 2 O 5 : 0.2 to 1.0% by weight, MnO 2 : not more than 1.0% by weight, TiO 2 : not more than 0.4% by weight and x: 0.8 to 0.96, τf: -12 to +7 ppm/°C., Qu: 800 to 1600, and εr: 45 to 50. (3) Effect of the example in V 2 O 5 --MnO 2 --PbO system composition According to the results of Table 7 and FIGS. 39 to 46 and FIGS. 51 to 62, if V 2O 5 is not added (No. 1 in Table 7), sintering is insufficient and measurement for each of the characteristics is impossible. Then, since τf and Qu change by the addition (each in FIGS. 41 and 40), τf and Qu can be controlled. Particularly, since τf increases along with the addition up to 0.6% and Qu increases along with addition up to 0.8% by weight, such addition is preferred. Further, εr increases along with addition of MnO 2 (FIG. 43). Further, τf increases along with addition up to 0.4% by weight (FIG. 45). Since Qu decreases by the addition, a great amount of addition is not preferred (FIG. 44). Since τf changes along with addition of PbO (mainly in the negative direction), it shows that τf can be controlled easily (FIG. 53). Further, since εr increases with the addition, it is preferred (FIG. 51). Since Qu decreases with the addition, a great amount of addition is not preferred (FIG. 52). Further, since τf changes greatly along with increase of the value x in Bi(NbxTa1-x)O 4 (mainly changes in the positive direction) (FIG. 57), τf can be controlled by the change of the value x. Further, since Qu increases along with increases of the value x, it is preferred (FIG. 56). While the sintering density tends to lower with the addition, 7.04 kg/m 3 of the sintering density can be ensured even x is 1.0 (No. 29 in Table 7, FIG. 54). Further, referring to the sintering temperature, sufficient sintering is attained at 850° to 950° C. (FIG. 62) and physical properties are also stable (FIGS. 59-62). Like that in the V 2 O 5 --MnO 2 --TiO 2 system composition. As described above, while each of the characteristics changes variously in accordance with the kind of each of the additives, the addition amount thereof and the sintering temperature, the following well balanced practical performances is shown, for example, within a compositional range shown below according to the results of this example (Table 7). For instance, the V 2 O 5 --MnO 2 --PbO system compositions exhibit the following well balanced practical performances. (1) At V 2 O 5 : 0.4 to 0.8% by weight, MnO 2 and PbO: both 0.2% by weight and x: 0.8, εr: 44.9 to 46.8, Qu: 1460 to 1950, τf: -14.5 to -1.7 ppm/°C. (2) At V 2 O 5 : 0.6% by weight, MnO 2 and PbO: both 0.2% by weight and x: 0.8, εr: 46.5, Ou: 1430, τf: -1.75 ppm/°C. (3) At MnO 2 : 0.2 to 0.4% by weight, V 2 O 5 : 0.4% by weight, PbO: 0.2% by weight and x: 0.8, εr: 46.8 to 47.9, Qu: 1351 to 1465, τf: -6.3 to -2.1 ppm/°C. (4) At PbO: 0.2 to 0.4% by weight, V 2 O 5 : 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8, εr: 46.8 to 47.4, Qu: 1293 to 1465, τf: -13.2 to -6.3 ppm/°C. (5) At V 2 O 5 :0.3 to 0.8% by weight, MnO 2 : 0.1 to 1.0% by weight, PbO: not more than 0.4% by weight and x: 0.8 to 0.96, τf: -15 to +4 ppm/°C., Qu: 1000 to 2000 and εr: 44 to 49. The present invention is not restricted to the concrete examples as described above but variously modified embodiment can be made within a scope of the present invention in accordance with the purpose and application uses thereof.
The present invention provides a microwave dielectric ceramic composition in which εr, Qu and τf are generally controlled within a practical characteristic range and each of the characteristics is maintained in a well balanced state. A ceramic composition of the present invention comprises a composition represented by xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ) in which 0.45≦x≦0.55 and 0.1≦y<1.0 as a main ingredient, to which not more than 0.8 parts by weight of V 2 O 5 is added and incorporated. An another ceramic composition comprises a composition represented by Bi(NbxTa1-x)O 4 in which 0<x≦0.96 as a main ingredient, to which not more than 5 wt % of V 2 O 5 and not more than 2 wt % of PbO are added and incorporated. An another ceramic composition comprises the main ingredient as described above to which not more than 5 wt % of V 2 O 5 and not more than 2 wt % of MnO 2 are added and incorporated. An another ceramic composition comprises the main ingredient as described above to which not more than 2 wt % of V 2 O 5 and not more than 1 wt % of TiO 2 are added and incorporated. An another ceramic composition comprises the main ingredient as described above, to which not more than 2 wt % of V 2 O 5 , not more than 2 wt % of MnO 2 and not more than 0.7 wt % of TiO 2 are added and incorporated. Instead of TiO 2 described above, not more than 0.5 wt % (particularly not more than 0.4 wt %) of PbO can be added and incorporated.
Briefly describe the main invention outlined in the provided context.
[ "BACKGROUND OF THE INVENTION The present invention concerns a microwave dielectric ceramic composition and, more in particular, it relates to a microwave dielectric ceramic composition having a temperature coefficient of a resonance frequency (hereinafter simply referred to as τf) varied generally within a practical characteristic range while maintaining a practical unload Q (hereinafter simply referred to Qu) and a greatly improved specific dielectric constant (hereinafter simply referred to as εr).", "The present invention also concerns a microwave dielectric ceramic composition in which each of the characteristic is balanced at a practical level.", "The present invention further concerns a microwave dielectric ceramic composition in which εr and Qu are controlled generally within a practical characteristic range while maintaining τf at a practical high level and each of the characteristics is balanced at a high level.", "The present invention further concerns a microwave dielectric ceramic composition in which εr, Qu and τf are controlled generally within a practical characteristic range and each of the characteristics is maintained in a well balanced state.", "The present invention is utilized for impedance matching or the like of dielectric resonators, microwave integrated circuit substrate, various kinds of microwave circuits in a microwave region and it is particularly suitable to LC filter materials.", "Generally, LC filter materials, dielectric resonators, dielectric substrates used in a region of high frequency waves such as microwaves or milliwaves are required to have high εr and high flu, as well as small absolute value for the temperature coefficient of the resonance frequency.", "Namely, since the dielectric loss of a microwave dielectric ceramic composition (hereinafter simply referred to as dielectric ceramic composition) tends to increase as the working frequency becomes higher, a dielectric ceramic composition having large εr and Qu in a microwave region is desired.", "For such a dielectric ceramic composition, a composition belonging to a composite perovskite structure such as Ba(Zn 1/3 Ta 2/3 )O 3 or Ba(Mg 1/3 Ta 2/3 )O 3 or BaO--TiO 2 system composition has been used in recent years, but any of them requires a high sintering temperature of 1300° C. or higher.", "Such a high sintering temperature requires greater power electric power consumption during sintering to result in a drawback of causing a disadvantage in view of production cost or productivity.", "Further, in a case of sintering together with a conductor having a low melting point as an electrode, for example, silver (melting point: 961° C.) or copper (melting point: 1083° C.) as in an LC filter or a strip line filter, it is particularly advantageous that the sintering temperature is lower than the melting point of the conductor.", "Accordingly, a material sinterable at a temperature as low as possible is demanded.", "SUMMARY OF THE INVENTION An object of the present invention is to provide a dielectric ceramic composition capable of having τf varying generally within a practical range and high εr while maintaining high Qu by a composition comprising a main ingredient of Bi 2 O 3 --Nb 2 O 5 --Ta 2 O 5 system and a predetermined amount of V 2 O 5 added and incorporated thereto.", "The present inventor has made various studies on Bi 2 O 3 ---Nb 2 O 5 --Ta 2 O 5 system compositions having τf varied generally within a practical characteristic range while maintaining high Qu, having high εr and capable of being produced by sintering at a low temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can be attained by varying the ratio between Nb 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 thereto.", "That is, the dielectric ceramic composition according to the present invention comprises a composition represented by xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ) in which 0.45≦x≦0.55 and 0<y<1.0 as a main ingredient, to which not more than 0.8 parts by weight (not including 0 part by weight) of V 2 O 5 s is added and incorporated based on 100 parts by weight of the xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ).", "In the above-mentioned invention, x is defined as 0.45 to 0.55, because Qu is too small if x is less than 0.45 or exceeds 0.55.", "Further, y is within a range: 0<y<1.0.", "If Nb 2 O 5 is not present (y=0), the absolute value for τf tends to increase (decrease in a negative direction) and εr tends to decrease.", "If N 2 O 5 is present even in a small amount, εr which is important for LC filter material tends to be improved.", "On the other hand if y is at 1.0, εr tends to decrease and Qu tends to decrease as y increases.", "Further, the addition ratio of V 2 O 5 is defined as not more than 0.8% by weight (not including 0% by weight), because Qu tends to decrease if it is added in excess of 0.8% by weight although the addition of V 2 O 5 can lower the sintering temperature.", "Further, a case in which α is 0% by weight, that is, of V 2 O 5 is not added is excluded, because this makes sintering insufficient and lowers each of the characteristics.", "The addition amount of V 2 O 5 at 0.4% by weight is more preferred since Qu increases much higher as compared with the case of addition of 0.8% by weight, 0.6% by weight and 0.2% by weight (Nos.", "5-8 compared with Nos. 13-16, Nos. 9-12 and 1-4 in Table 1).", "In particular, it is preferred that x is from 0.47 to 0.53, y is from 0.4 to 0.8 and α is from 0.4 to 0.6, since each physical property is balanced.", "In this case, εr is from 42.9 to 47.7, Qu is from 790 to 1490 and τf is from -46.4 to -16.2 ppm/°C.", "Further, the dielectric ceramic composition of the present invention is produced as described below.", "Specifically, bismuth oxide (III) powder, niobium oxide (V) powder, tantalum oxide (V) powder and vanadium oxide (V) powder are mixed so as to provide a composition comprising a composition represented by xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 in which 0.45≦x≦0.55 and 0<y<1.0 as a main ingredient, to which not more than 0.8 parts by weight (not including 0 part by weight) of V 2 O 5 is added and incorporated based on 100 parts by weight of the xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ) and then calcined to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 860°-950° C. The sintering temperature is defined as within 860° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range.", "Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter.", "The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere.", "In the dielectric ceramic composition according to the present invention, τf can be varied widely within a practical characteristic range while maintaining Qu at a level with no practical problem by setting each of the oxides a predetermined ratio in the Bi 2 O 3 --Nb 2 O 5 --Ta 2 O 5 system, to which a predetermined amount of V 2 O 5 is added.", "Further, a dielectric ceramic composition having extremely high εr and suitable to LC filter material can be obtained.", "Further, the dielectric ceramic composition according to the present invention can be prepared by sintering at a relatively low temperature as 860° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor.", "An object of the present invention is to provide a dielectric ceramic composition in which (Qu and τf are controlled within a wide characteristic range while maintaining εr at a high and each of the characteristics is balanced at a practical level, by with a composition comprising Bi(NbTa)O 4 as a main ingredient to which V 2 O 5 and PbO is added each in a predetermined amount.", "The present inventor has made various studies on Bi(NbTa)O 4 system compositions having Qu and τf cotroled within a wide practical characteristic range while maintaining high εr and capable of being produced by sintering at a low and wide temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can be attained by varying the ratio between Nb 2 O 5 and Ta 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 and PhO thereto.", "The dielectric ceramic composition of the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 in which 0<x≦0.96 as a main ingredient to which not more than 5% by weight (not including 0% by weight) of V 2 O 5 and not more than 2% by weight (not including 0% by weight) of PbO are added and incorporated based on 100% by weight of Bi(NbxTa1-x)O 4 .", "In the above-mentioned invention, x is defined as: 0<x≦0.96, because the Ta 2 O 5 ingredient is substantially absent if x exceeds 0.96, making it difficult to control εr and τf.", "Further, the addition amount of V 2 O 5 is defined as greater than 0 and not more than 5% by weight, because addition in excess of 5% by weight can not provide any further effect and it rather results in deterioration of other characteristics such as Qu, although the sintering temperature can be lowered by the addition of V 2 O 5 , and because sintering is insufficient to lower each of the characteristics if V 2 O 5 is not added.", "The addition amount of V 2 O 5 within a range from 0.2 to 2.0% by weight is more preferred since a practical dielectric ceramic composition showing well balanced in each of the characteristics can be obtained.", "Further, the addition amount of PbO is greater than 0 and not more than 2% by weight.", "Addition of PbO can increase εr and Qu as compared with a case of not adding PbO at all.", "However, although εr is improved in proportion with the addition amount of PbO, Qu reaches a peak at the addition amount of 0.2% by weight and tends to reduce beyond the peak, τf tends to increase in the negative direction in proportion with the addition of PbO.", "This trend is remarkable if the addition amount is as great as 1 to 2% by weight.", "Accordingly, for obtaining a dielectric ceramic composition well balanced in each of the characteristics and having a high level, it is preferred that the addition amount of PbO is within a range from 0.1 to 1.0% by weight.", "Further, it is preferred that x is from 0.2 to 0.9 (table 1 and 2), the addition amount of V 2 O 5 is from 0.2 to 2.0% by weight and the addition amount of PbO is from 0.2 to 0.6% by weight (table 3).", "In this case, εr is from 45 to 48, Qu is from 960 to 1640 (at from 3.6 to 4.0 GHz) and τf is from -47 to -36 ppm/°C.", "Further, the dielectric ceramic composition of the present invention is produced as described below.", "The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 850°-950° C. The sintering temperature is defined as within 850° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range.", "Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter.", "The sintering can he carried out either in an ambient atmosphere or a reducing atmosphere.", "In the dielectric ceramic composition according to the present invention, a dielectric ceramic composition well balanced in each of the characteristics such as Qu and τf while maintaining practically high εr and suitable to LC filter material can be obtained by setting each of the oxides at a predetermined ratio in the Bi(NbTa)O 4 system, to which V 2 O 5 and PbO are added each in a predetermined amount.", "Further, a composition of particularly excellent performance can he obtained in a range of relatively lower addition amount of PbO.", "Further, the dielectric ceramic composition according to the present invention can he prepared by sintering at a relatively low and wide temperature as 850° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor.", "An object of the present invention is to provide a dielectric ceramic composition in which εr and Qu are controlled widely within a practical characteristic range while maintaining τf at a practically high level and each of the characteristics is balanced at a high level, by a composition comprising a Bi(NbTa)O 4 system as a main ingredient to which V 2 O 5 and MnO 2 are added and incorporated each by a predetermined amount.", "The present inventor has made various studies on Bi(NbTa)O 4 system compositions having εr and Qu cotroled widely within a practical characteristic range while maintaining practical high τf and capable of being produced by sintering at a low and wide temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can be attained by varying the ratio between Nb 2 O 5 and Ta 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 and MnO 2 thereto.", "The dielectric ceramic composition according to the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 in which 0<x ≦0.96 as a main ingredient, to which not more than 5% by weight (not including 0% by weight) of V 2 O 5 and not more than by weight (not including 0% by weight) of MnO 2 are added and incorporated based on 100% by weight of Bi(NbxTa1-x)O 4 .", "Further, in the present invention, the addition amount of MnO 2 may be from 0.1 to 1.0% by weight based on 100% by weight of Bi(NbxTa1-x)O 4 .", "In the above-mentioned invention, x is defined as: 0<x≦0.96, because the Ta 2 O 5 ingredient is substantially absent if x exceeds 0.96, making it difficult to control εr and τf.", "Further, the addition amount of V 2 O 5 is defined as greater than 0 and not more than 5% by weight, because addition in excess of 5% by weight can not provide any further effect and it rather results in deterioration of other characteristics such as Qu, although the sintering temperature can be lowered by the addition of V 2 O 5 , and because sintering is insufficient to lower each of the characteristics if V 2 O 5 is not added.", "The addition amount of V 2 O 5 within a range from 0.2 to 2.0% by weight is more preferred since a practical dielectric ceramic composition showing well balanced in each of the characteristics can be obtained.", "The addition amount of MnO 2 is more than 0 and not more than 2% by weight and the addition of MnO 2 can improve all of τf, εr and Qu with a certain exception as compared with a case of not adding MnO 2 at all.", "However, although εr is improved linearly in proportion with the addition mount of MnO 2 , τf rather decreases depending on the case as the addition amount of τf exceeds 1% by weight, particularly, as the sintering temperature goes higher, while Qu reaches a peak at the addition amount of 0.2% by weight and tends to lower beyond the peak.", "Accordingly, for obtaining a dielectric ceramic composition well balanced in each of the characteristics at a high level, it is preferred that the addition amount of MnO 2 is within a range from 0.1 to 1.0% by weight Further, it is preferred that x is from 0.2 to 0.9 (tables 1 and 2), the addition amount of V 2 O 5 is from 0.2 to 2.0% by weight and the addition amount of MnO 2 is from 0.1 to 0.6% by weight (table 4).", "In this case, εr is from 45 to 47, Qu is from 970 to 1640 (at from 3.6 to 3.9 GHz) and τf is from -14 to -5.5 ppm/°C.", "Further, the dielectric ceramic composition of the present invention is produced as described below.", "The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 850°-950° C. The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere.", "The sintering temperature is defined as within 850° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range.", "Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter.", "In the dielectric ceramic composition according to the present invention, a dielectric ceramic composition well balanced in each of the characteristics such as εr and Qu while maintaining practically high τf and suitable to LC filter material can be obtained by setting each of the oxides at a predetermined ratio in the Bi(NbTa)O 4 system, to which V 2 O 5 and MnO 2 are added each in a predetermined amount.", "Further, a composition of particularly excellent performance can be obtained in a range of relatively lower addition amount of MnO2.", "Further, the dielectric ceramic composition according to the present invention can be prepared by sintering at a relatively low and wide temperature as 850° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor.", "An object of the present invention is to provide a microwave dielectric ceramic composition in which εr, Qu and τf are controlled widely within a practical characteristic range and each of the characteristics is maintained in a well balanced state, by a composition comprising Bi(NbTa)O 4 system as a main ingredient to which V 2 O 5 and TiO 2 are added each in a predetermined amount.", "The present inventor has made various studies on Bi(NbTa)O 4 system compositions having εr, Qu and τf cotroled within a wide practical characteristic range and capable of being produced by sintering at a low temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can be attained by varying the ratio between Nb 2 O 5 and Ta 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 and TiO 2 thereto, and in particular the discovery that the foregoing object can be attained by cotroling τ f by an addition of TiO 2 .", "The dielectric ceramic composition according to the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 ) in which 0<x≦0.96 as a main ingredient to which not more than 2% by weight (not including 0% by weight) of V 2 O 5 and not more than 1% by weight (not including 0% by weight) of TiO 2 are added and incorporated based on 100% by weight of the Bi(NbxTa1-x)O 4 ).", "In the above-mentioned invention, x is defined as: 0<x≦0.96, because the Ta 2 O 5 ingredient is substantially absent if x exceeds 0.96, making it difficult to control εr and τf.", "By varying the addition amount of Ta 2 O 5 , control for εr and τf is facilitated and, particularly, by increasing the addition amount of Ta 2 O 5 , εr and Qu can be increased.", "Further, the addition amount of V 2 O 5 is determined as more than 0 but not more than 2% by weight, because V 2 O 5 functions as a sintering aid and, accordingly, can lower the sintering temperature and stabilize the performance by the addition, but addition in excess of 2% by weight decreases Qu and τf, whereas no addition of V 2 O 5 makes sintering insufficient and decreases each of the characteristics.", "The addition amount of V 2 O 5 , particularly, within a range from 0.3 to 0.5% by weight (particularly around 0.4% by weight) is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics is obtained.", "Further, the addition amount of TiO 2 is defined as not more than 1% by weight, because each of the characteristics decreases remarkably if the addition amount exceeds about 1% by weight.", "TiO 2 has an effect of transferring τf from a negative to positive direction by the addition and an addition amount within a range from 0.1 to 0.3% weight (particularly, 0.2% by weight) is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics is obtained.", "Further, x is from 0.6 to 0.96, the addition amount of V 2 O 5 may be from 0.2 to 1.0% by weight and the addition amount of TiO 5 may be from 0.1 to 0.6% by weight.", "This is because well balanced performance can be obtained for εr, Qu and τf within such a range of addition.", "Further, a practical balanced performance such as τf from -30 to 0 ppm/°C.", ", Qu from 510 to 1160, εr from 42 to 58 can be obtained with the above-mentioned composition.", "Further, the dielectric ceramic composition of the present invention is produced as described below.", "The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined at 600°-800° C. to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 875°-950° C. The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere.", "The sintering temperature is defined as within 875° to 950° C., because a sintering temperature of less than 875° C. may make sintering insufficient, a sufficient sintering density is ensured by sintering within this sintering range and the performance is stabilized.", "Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter.", "In the dielectric composition according to the present invention, εr, Qu and τf are within a practical characteristic range and each of the characteristics is maintained in a well balanced state.", "Accordingly, it is suitable to the LC filter material.", "Further, the dielectric ceramic composition according to the present invention can be prepared by sintering at a relatively low and wide temperature as 875° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor.", "An object of present invention is to provide a microwave dielectric ceramic composition in which εr, Qu and τf are controlled within a wide practical characteristic range and each of the characteristics is maintained in a well balanced state, by a composition comprising a Bi(NbTa)O 4 system as a main ingredient, to which V 2 O 5 and MnO 2 , as well as TiO 2 or PbO are added and incorporated each in a predetermined amount.", "The present inventor has made various studies on Bi(NbTa)O 4 system compositions having εr, Qu and τf cotroled widely within a practical characteristic range and capable of being produced by sintering at a low temperature and, as a result, has accomplished the present invention based on the discovery that the foregoing object can he attained by varying the ratio between Nb 2 O 5 and Ta 2 O 5 in the above-mentioned composition and, further, adding a predetermined amount of V 2 O 5 , MnO 2 and TiO 2 (or PbO) thereto.", "The dielectric ceramic composition according to the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 in which 0<x≦0.96 as a main ingredient, to which not more than 2% by weight (not including 0% by weight) of V 2 O 5 , not more than 2% by weight (not including 0% by weight) of MnO 2 and not more than 0.7% by weight (not including 0% by weight) of TiO 2 are added and incorporated based on 100% by weight of Bi(NbxTa 1 -x)O 4 .", "In the above-mentioned invention, x is defined as: 0<x≦0.96, because the Ta 2 O 5 ingredient is substantially absent if x exceeds 0.96, making it difficult to control εr and τf.", "Since V 2 O 5 functions as a sintering aid, addition thereof can lower the sintering temperature and stabilize the performance.", "If the addition amount of V 2 O 5 exceeds 2% by weight, it decreases Qu and τf, whereas if V 2 O 5 is not added, sintering is insufficient to decrease each of the characteristics.", "An addition amount of V 2 O 5 , particularly, from 0.2 to 1.0% by weight (preferably, from 0.3 to 0.5% by weight, more preferably, about 0.4% by weight) is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained.", "For instance, at the addition amount: (1) from 0.2 to 1.0% by weight (MnO 2 and TiO 2 : both 0.2% by weight, x: 0.8), εr is 46.6 to 47.9, Qu is 890 to 1300 as τf is -10.91 to -2.45 ppm/°C.", "and (2) addition amount of 0.4% by weight (MnO 2 and TiO 2 : both 0.2% by weight, x: 0.8), εr is 47.1, Qu is 1325 and τf is -7.46 ppm/°C.", "Further, both of Qu and τf are improved by the addition of MnO 2 up to 0.4% by weight.", "Accordingly, since MnO 2 has an effect of transferring τf from negative to positive direction within this addition range, it is effective to adjust τf from negative to positive direction.", "On the other hand, if it is added by more than 2% by weight, it is not preferred since tends to decrease greatly.", "Particularly, an addition amount of not more than 1.0% by weight is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained.", "For instance, at the addition amount of from 0.2 to 1.0% by weight (V 2 O 5 ;", "0.4% by weight, TiO 2 ;", "0.2% by weight, x;", "0.8), εr is 47.0 to 47.5, Qu is 900 to 1440 and τf is -6.0 to -11.1 ppm/°C.", "Further, the addition amount of TiO 2 is defined as not more than 0.7% by weight, because Qu is decreases greatly and τf transfers in the positive direction apart from 0 if the addition amount is more than 0.7% by weight.", "Since TiO 2 has an effect of transferring τf from negative to positive direction by the addition, it is effective for adjusting τf from negative to positive direction.", "Particularly, a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained with an addition amount of 0.1 to 0.2% by weight.", "For instance, at the addition amount from 0.1 to 0.2% by weight (V 2 O 5 ;", "0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8), εr is46.4 to 47.1, Qu is 1320 to 1490 and τf is -8.8 to -7.5 ppm/°C.", "Further, it is possible to set the addition amount of V 2 O 5 as 0.2 to 1.0% by weight, the addition amount of MnO 2 of not more than 1.0% by weight and the addition amount of TiO 2 of not more than 0.4% by weight and x as 0.8 to 0.96, because the performance is well balanced in this case.", "For instance, it is possible to attain τf: -12 to +7 ppm/°C.", ", Qu: 800 to 1600 and εr: 45 to 50.", "Further, the dielectric ceramic composition of the present invention is produced as described below.", "The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined at 600°-800° C. to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 850°-950° C. The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere.", "The sintering temperature is defined as within 850° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range.", "Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter.", "A dielectric ceramic composition according to the present invention comprises a composition represented by Bi(NbxTa1-x)O 4 , in which 0<x≦0.96 as a main ingredient, to which 0.2 to 1% by weight of V 2 O 5 , not more than 1% by weight (not including 0% by weight) of MnO 2 and not more than 0.5% by weight (not including 0% by weight) of PbO are added and incorporated.", "The reason why x is defined as 0<x≦0.96 in this invention is identical with the reason explained for the first invention.", "Further, since V 2 O 5 functions as a sintering aid, addition thereof can lower the sintering temperature and stabilize the performance.", "If the addition amount exceeds 1% by weight, Qu decreases and it decreases remarkably to about 510 at the addition amount of 3% by weight.", "Further, if the addition amount exceeds 1% by weight, τf is not more than -24 ppm/°C.", ", that is, increases toward the negative direction.", "Further, if is not added sintering is insufficient and Qu decreases, which is not desired.", "The addition amount of V 2 O 5 , particularly, from 0.4 to 0.8% by weight is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained.", "For instance, (1) at the addition amount of from 0.4 to 0.8% by weight (x: 0.8, MnO 2 and PbO: both 0.2% by weight), εr is 44.9 to 46.8, Qu is 1460 to 1950 as τf is -14.5 to -1.7 ppm/°C.", "and (2) addition amount of 0.6% by weight (x: 0.8, MnO 2 and PbO: both 0.2% by weight), εr is 46.5, Qu is 1430 and τf is -1.75 ppm/°C.", "and τ f is nearly 0.", "Further, addition of MnO 2 can increase εr and τf.", "Since the addition of this ingredient has a function of transferring particularly, τf from negative to positive direction, so that it is effective for adjusting τf from negative to positive direction.", "On the other hand, if addition amount is more than 1% by weight, Qu tends to decrease remarkably, which it is not preferred.", "Particularly, the addition amount of MnO 2 from 0.2 to 0.4% by weight (V 2 O 5 ;", "0.4% by weight, PbO;", "0.2% by weight and x;", "0.8) is preferred since this can provide a practical dielectric ceramic composition well balanced in each of the characteristics as εr: 46.8 to 47.9, Qu: 1351 to 1465 and τf: -6.3 to -2.1 ppm/°C.", "Further, the addition amount of PbO is defined as not more than 0.5% by weight, because Qu and τf decrease greatly if the addition amount is more than 0.5% by weight.", "Since PbO has an effect of transferring, particularly, τf from positive to negative direction by the addition, it is effect ire for adjusting τf from positive to negative direction.", "Particularly, the addition amount of PbO from 0.2 to 0.4% by weight (V 2 O 5 : 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8) is more preferred since a practical dielectric ceramic composition well balanced in each of the characteristics can be obtained as εr: 46.8 to 47.4, Qu: 1293 to 1465, τf;", "-13.2 to -6.3 ppm/°C.", "Further, it is possible to set the addition amount of V 2 O 5 as 0.3 to 0.8% by weight, the addition amount of MnO 2 as 0.1 to 1.0% by weight, the addition amount of PbO as not more than 0.4% by weight and x as from 0.8 to 0.96, because the performances are well balanced in this case.", "For instance, it is possible to attain τf;", "-15 to +4 ppm/°C.", ", Qu: 1000 to 2000 and εr: 44-49.", "Further, the dielectric ceramic composition of the present invention is produced as described below.", "The predetermined metal oxide powders are mixed so as to provide a predetermined composition and then calcined at 600°-800° C. to prepare a calcined powder, which is pulverized, molded into a predetermined shape and then sintered at 850°-950° C. The sintering temperature is defined as within 850° to 950° C., because Qu decreases and τf increases excessively in the negative direction out of the temperature range.", "Further, low temperature sintering is particularly preferred in a case of sintering simultaneously with a conductor such as for an LC filter.", "The sintering can be carried out either in an ambient atmosphere or a reducing atmosphere.", "In the dielectric ceramic composition according to the present invention, εr, Qu and τf are within a practical characteristic range and each of the characteristics is maintained in a well balanced state.", "Accordingly, it is suitable to the LC filter material.", "Further, the dielectric ceramic composition according to the present invention can be prepared by sintering at a relatively low and wide temperature as 850° to 950° C. Such low temperature sintering is particularly advantageous in a case of the LC filter which is sintered simultaneously with a conductor.", "BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing a relation between x and εr in (the main ingredient represented by xBi 2 O 3 -(1-x) (0.8Nb 2 O 5 -0.2Ta 2 O 5 )+0.4% by weight of V 2 O 5 ).", "FIG. 2 is a graph showing a relation between x and Qu in (a main ingredient represented by xBi 2 O 5 -(1-x) (0.8Nb 2 O 5 -0.2Ta 2 O 5 )+0.4% by weight of V 2 O 5 ).", "FIG. 3 is a graph showing a relation between x and τf in (the main ingredient represented by xBi 2 O 3 -(1-x) (0.8Nb 2 O 5 -0.2Ta 2 O 5 )+0.4% by weight of V 2 O 5 ).", "FIG. 4 is a graph showing a relation between y of the main ingredient represented by 0.5Bi 2 O 3 -0.5(yNb 2 O 5 -(1-y) Ta 2 O 5 ) and the addition amount of (α) of V 2 O 5 , and εr.", "FIG. 5 is a graph showing a relation between y of the main ingredient represented by 0.5Bi 2 O 3 -0.5(yNb 2 O 5 -(1-y) Ta 2 O 5 ) and the addition amount (α) of V 2 O 5 , and Qu.", "FIG. 6 is a graph showing a relation between y of the main ingredient represented by 0.5Bi 2 O 5 -0.5(yNb 2 O 5 -(1-y) Ta 2 O 5 ) and the addition amount (α) of V 2 O 5 , and τf.", "FIG. 7 is a graph showing a relation between the sintering temperature and the addition amount (δ) of PbO, and εr in (the main ingredient represented by Bi(Nb 0 [.", "].6 Ta 0 [.", "].4)O 0 [.", "].4)O 4 +0.4% by weight of V 2 O 5 ).", "FIG. 8 is a graph showing a relation between the sintering temperature and the addition amount (δ) of PbO, and Qu in (the main ingredient represented by Bi(Nb 0 [.", "].6 Ta 0 [.", "].4)O 4 +0.4% by weight of V 2 O 5 ).", "FIG. 9 is a graph showing a relation between the sintering temperature and the addition amount (δ) of PhO, and τf in (the main ingredient represented by Bi(Nb 0 [.", "].6 Ta 0 [.", "].4)O 4 +0.4% by weight of V 2 O 5 ).", "FIG. 10 is a graph showing a relation between the sintering temperature and the addition amount (δ) of PbO, and the sintering density in (the main ingredient represented by Bi(Nb 0 [.", "].6 Ta 0 [.", "].4)O 4 +0.4% by weight of V 2 O 5 ).", "FIG. 11 is a graph showing a relation between the addition amount (δ) of PbO and εr in (the main ingredient represented by Bi(Nb 0 [.", "].6 Ta 0 [.", "].4)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 12 is a graph showing a relation between the addition amount (δ) of PbO and Qu in (the main ingredient represented by Bi(Nb 0 [.", "].6 Ta 0 [.", "].4)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 13 is a graph showing a relation between the addition amount (δ) of PbO and τf in (the main ingredient represented by Bi(Nb 0 [.", "].6 Ta 0 [.", "].4)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 14 is a graph showing a relation between the addition amount (δ) of PbO and the sintering density in (the main ingredient represented by Bi(Nb 0 [.", "].6 Ta 0 [.", "].4)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 15 is a graph showing a relation between the sintering temperature and the addition amount (β) of MnO 2 , and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 ).", "FIG. 16 is a graph showing a relation between the sintering temperature and the addition amount (β) of MnO 2 , and Qu in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 ).", "FIG. 17 is a graph showing a relation between the sintering temperature and the addition amount (β) of MnO 2 , and τf (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2O 5 ).", "FIG. 18 is a graph showing a relation between the sintering temperature and the addition amount (β) of MnO 2 , and the sintering density in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 ).", "FIG. 19 is a graph showing a relation between the addition amount (β) of MnO 2 and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 20 is graph showing a relation between the addition amount (β) of MnO 2 and Qu in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 21 is a graph showing a relation between the addition amount (β) of MnO 2 and τf in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 22 is a graph showing a relation between the addition amount (β) of MnO 2 and the sintering density in (the ma in ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 23 is a graph showing a relation between the addition amount (γ) of TiO 2 and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 ) and in case of 900° C. of sintering temperature.", "FIG. 24 is a graph showing a relation between the addition amount (γ) of TiO 2 and Qu in the ceramic composition and the sintering temperature in FIG. 23.", "FIG. 25 is a graph showing a relation between the addition amount (γ) of TiO 2 and τf in the ceramic composition and the sintering temperature in FIG. 23.", "FIG. 26 is a graph showing a relation between the addition amount (γ) of TiO 2 and the sintering density in the ceramic composition and the sintering temperature in FIG. 23.", "FIG. 27 is a graph showing a relation between the addition amount (α) of V 2 O 5 and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.2% by weight of TiO 2 ) and in case of 900° C. of sintering temperature.", "FIG. 28 is a graph showing a relation between the addition amount (α) of V 2 O 5 and Qu in the ceramic composition and the sintering temperature in FIG. 27.", "FIG. 29 is a graph showing a relation between the addition amount (α) of V 2 O 5 and τf in the ceramic composition and the sintering temperature in FIG. 27.", "FIG. 30 is a graph showing a relation between the addition amount (α) of V 2 O 5 and the sintering density in the ceramic composition and the sintering temperature in FIG. 27.", "FIG. 31 is a graph showing a relation between x and εr in (the main ingredient represented by Bi(Nbx Ta1-x)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of TiO 2 ) and in case of 900° C. of sintering temperature.", "FIG. 32 is a graph showing a relation between x and Qu in the ceramic composition and the sintering temperature in FIG. 31.", "FIG. 33 is a graph showing a relation between x and τf in the ceramic composition and the sintering-temperature in FIG. 31.", "FIG. 34 is a graph showing a relation between x and the sintering density in the ceramic composition and the sintering temperature in FIG. 31.", "FIG. 35 is a graph showing a relation between the sintering temperature and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of TiO 2 ).", "FIG. 36 is a graph showing a relation between the sintering temperature and Qu in the ceramic composition in FIG. 35.", "FIG. 37 is a graph showing a relation between the sintering temperature and τf in the ceramic composition in FIG. 35.", "FIG. 38 is a graph showing a relation between the sintering temperature and the sintering density in the ceramic composition in FIG. 35.", "FIG. 39 is a graph showing a relation between the addition amount (α) of V 2 O 5 and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.2% by weight of MnO 2 +0.2% by weight of TiO 2 (or PbO)) and in case of 900° C. of sintering temperature.", "FIG. 40 is a graph showing a relation between the addition amount (α) of V 2 O 5 and Qu in the ceramic composition and the sintering temperature in FIG. 39.", "FIG. 41 is a graph showing a relation between the addition amount (α) of V 2 O 5 and τf in the ceramic composition and the sintering temperature in FIG. 39.", "FIG. 42 is a graph showing a relation between the addition amount (α) of V 2 O 5 and the sintering density in the ceramic composition and the sintering temperature in FIG. 39.", "FIG. 43 is a graph showing a relation between the addition amount (β) of MnO 2 and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of TiO 2 (or PbO)) and in case of 900° C. of sintering temperature.", "FIG. 44 is a graph showing a relation between the addition amount (β) of MnO 2 and Qu in the ceramic composition and the sintering temperature in FIG. 43.", "FIG. 45 is a graph showing a relation between the addition amount (β) of MnO 2 and τf in the ceramic composition and the sintering temperature in FIG. 43.", "FIG. 46 is a graph showing a relation between the addition amount (β) of MnO 2 and the sintering density in the ceramic composition and the sintering temperature in FIG. 43.", "FIG. 47 is a graph showing a relation between the addition amount (γ) of TiO 2 and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of MnO 2 ) and in case of 900 ° C. of sintering temperature.", "FIG. 48 is a graph showing a relation between the addition amount (γ) of TiO 2 and Qu in the ceramic composition and the sintering temperature in FIG. 47.", "FIG. 49 is a graph showing a relation between the addition amount (γ) of TiO 2 and τf in the ceramic composition and the sintering temperature in FIG. 47.", "FIG. 50 is a graph showing a relation between the addition amount (γ) of TiO 2 and the sintering density in the ceramic composition and the sintering temperature in FIG. 47.", "FIG. 51 is a graph showing a relation between the addition amount (δ) of PbO and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of MnO 2 ) and in case of 900 ° C. of sintering temperature.", "FIG. 52 is a graph showing a relation between the addition amount (δ) of PhO and Qu in the ceramic composition and the sintering temperature in FIG. 51.", "FIG. 53 is a graph showing a relation between the addition amount (δ) of PbO and τf in the ceramic composition and the sintering temperature in FIG. 51.", "FIG. 54 is a graph showing a relation between the addition amount (δ) of PbO and the sintering density in the ceramic composition and the sintering temperature in FIG. 51.", "FIG. 55 is a graph showing a relation between x and εr in (the main ingredient represented by Bi(Nbx Ta1-x)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of MnO 2 +0.2% by weight of TiO 2 (or PhO)) and in case of 900° C. of sintering temperature.", "FIG. 56 is a graph showing a relation between x and Qu in the ceramic composition and the sintering temperature in FIG. 55.", "FIG. 57 is a graph showing a relation between x and τf in the ceramic composition and the sintering temperature in FIG. 55.", "FIG. 58 is a graph showing a relation between x and the sintering density in the ceramic composition and the sintering temperature in FIG. 55.", "FIG. 59 is a graph showing a relation between the sintering temperature and εr in (the main ingredient represented by Bi(Nb 0 [.", "].8 Ta 0 [.", "].2)O 4 +0.4% by weight of V 2 O 5 +0.2% by weight of MnO 2 +0.2% by weight of TiO 2 (or PbO)).", "FIG. 60 is a graph showing a relation between the sintering temperature and Qu in the ceramic composition in FIG. 59.", "FIG. 61 is a graph showing a relation between the sintering temperature and τf in the ceramic composition in FIG. 59.", "FIG. 62 is a graph showing a relation between the sintering temperature and the sintering density in the ceramic composition in FIG. 59.", "DETAILED DESCRIPTION OF THE INVENTION EXAMPLES The present invention will be explained more specifically by way of examples.", "Example 1 Bi 2 O 3 a powder (purity: 98.9%), Nb 2 O 5 powder (purity: 99.9%), Ta 2 O 5 powder (purity: 99.9%) and V 2 O 5 powder (purity: 99.5%) were used as the raw material, and they are weighed and mixed each by a predetermined amount (about 600 g as the entire amount in each of the cases) so as to provide compositions in which x ranges from 0.43 to 0.57 and each of y and the addition amount of V 2 O 5 (α% by weight) varies within a range of 0 to 1.0 in xBi 2 O 3 -(1-x) (yNb 2 O 5 -(1-y)Ta 2 O 5 ) as shown in Tables 1 and 2.", "Subsequently, the weighed and mixed raw material powders were applied with primary pulverization by a vibration mill (3 hours) and then calcined in an ambient atmosphere at 700° C. for 2 hours.", "Then, an appropriate amount of an organic binder (15 g) and water (320 g) were added to each calcined powder and applied with secondary pulverization was conducted in a ball mill using alumina balls of 20 mmφ, at 90 rpm for 23 hours.", "Subsequently, they were pelletized by vacuum freeze drying (pressure: about 0.4 Torr, freezing temperature: -20° to -40° C., drying temperature: 40° to 50° C., drying time: about 20 hours).", "The thus pelletized raw materials were molded at a pressure of 1 ton/cm 2 to obtain cylindrical molding products each of 19 mmφ×10 mmt (height).", "TABLE 1______________________________________[0.5Bi.", "sub[.", "].2 O.sub[.", "].3 - 0.5 {yNb.", "sub[.", "].2 O.sub[.", "].5 - (1 - y) Ta.", "sub[.", "].2 O.sub[.", "].5} +αV.", "sub[.", "].2 O.sub[.", "].5] ceramic composition Rel.", "α dielect.", "(V.", "sub[.", "].2 O.sub[.", "].5) f.sub.", "o const.", "sub.", "fNo.", "y (wt %) (GHz) ε.", "sub.", "r Qu (ppm/°C.)______________________________________1 0.2 0.2 4.4 33.2 703 -56.82 0.4 0.2 4.0 42.5 510 -49.03 0.6 0.2 3.9 43.5 443 -41.24 0.8 0.2 3.9 43.1 491 -28.05 0.2 0.4 3.9 44.7 1344 -53.16 0.4 0.4 3.9 45.9 1488 -46.47 0.6 0.4 3.8 46.2 1305 -32.88 0.8 0.4 3.9 44.6 1487 -18.59 0.2 0.6 3.8 47.1 1014 -52.110 0.4 0.6 3.8 47.7 897 -39.811 0.6 0.6 3.8 46.6 791 -29.612 0.8 0.6 3.9 45.6 816 -18.513 0.2 0.8 3.7 49.0 746 -51.114 0.4 0.8 3.7 49.0 590 -36.215 0.6 0.8 3.8 48.0 505 -25.016 0.8 0.8 3.9 45.7 598 -18.9______________________________________ TABLE 2______________________________________[xBi.", "sub[.", "].2 O.sub[.", "].3 - (1 - x) {yNb.", "sub[.", "].2 O.sub[.", "].5 - (1 - y)Ta.", "sub[.", "].2 O.sub[.", "].5 } + αV.", "sub[.", "].2 O.sub[.", "].5] ceramic composition Rel.", "α dielect.", "(V.", "sub[.", "].2 O.sub[.", "].5) f.sub.", "o const.", "sub.", "fNo.", "x y (wt %) (GHz) ε.", "sub.", "r Qu (ppm/°C.)______________________________________17 0.43 0.8 0.4 4.0 41.6 243 -26.518 0.45 0.8 0.4 4.0 42.2 610 -18.019 0.47 0.8 0.4 4.0 42.9 1100 -16.220 0.49 0.8 0.4 3.9 44.0 1360 -17.321 0.51 0.8 0.4 3.9 45.0 1432 -23.122 0.53 0.8 0.4 3.9 44.8 1190 -27.023 0.55 0.8 0.4 4.0 43.9 780 -31.524 0.57 0.8 0.4 4.0 42.7 370 -38.025 0.5 0 0.2 4.6 30.8 829 -57.526 0.5 0 0.4 4.1 40.4 1115 -48.327 0.5 0 1.0 3.7 50.3 562 -36.528 0.5 1.0 0.2 4.1 42.3 476 -23.629 0.5 0.9 0.4 4.0 43.7 1450 -11.530 0.5 1.0 0.4 4.0 42.9 1504 -2.731 0.5 1.0 1.0 4.0 44.5 557 -6.232 0.5 0.4 0 4.9 29.8 203 -68.0______________________________________ Then, the molding products were degreased in an atmospheric air at 500° C. for 3 hours and then sintered at 850° to 900° C. for 2 hours to obtain sintering products.", "Finally, each of the sintering products was polished at both end faces into a cylindrical shape of about 16 mmφ×8 mmt (height), further cleaned with a diluted solution comprising 5 parts of an aqueous detergent ("Eriese K-2000"", "manufactured by Asahi Kasei Co.) and 100 parts of water mixed together, at 23° C. for 60 min, and dried at 80° C. for 10 hours to form dielectric specimens (Nos.", "1-32 in Tables 1 and 2).", "The temperature elevation rate was 200° C./h and the temperature lowering rate was -200° C./h in the calcining step, the temperature elevation rate was 50° C./h in the decreasing step, and the temperature elevation rate was 100° C./h and the temperature lowering rate was -100° C./h in the sintering step.", "Then, εr, Qu and τf were measured for each of the specimens by a parallel conductor plate dielectric columnar resonator method (TE 011 MODE) or the like.", "The resonance frequency upon measurement is as shown in Table 1 (f 0 ).", "Further, τf was measured at a temperature region from 23° to 80° C. and calculated according τf=(f 80 -f 23 )/(f 23 ×ΔT) and ΔT=80-23=57° C. The results are shown in Tables 1 and 2 and in the graphs of FIGS. 1 to 6.", "From the results, Qu decreases remarkably at x for 0.43 and 0.57 and εr also decreases considerably at x for 0.43 (No.", "17 in Table 2) and τf also decreases in the negative direction at x for 0.57 (No.", "24 in Table 2).", "On the other hand it can seen that within a range of x from 0.45 to 0.55, particularly, from 0.47 to 0.51, compositions excellent in all of εr, Qu and τf and well balanced in the characteristics is obtained (FIGS.", "1-3).", "Further, εr slightly decrease at y=1.0 and at a of 0.2% by weight (No.", "28 in Table 2) and 0.4% by weight (No.", "30 in Table 2) as compared with a case of y at 0.2 to 0.8.", "And if y is 0.9 and α is 0.4% by weight (No.", "29 in Table 2), balance of εr, Qu and τf is excellent.", "If y is 0, εr decreases further.", "Further, if y is 0, and α is 1.0 % by weight (No.", "27 in Table 2), although εr is excellent, Qu tends to decrease.", "Further, if y is 1.0, and αis 1.0% by weight (No.", "31 in Table 2), although τf is excellent, Qu decreases.", "If y is 0.4 and α is 0 (No.", "32 in Table 2), all εr, Qu and τf greatly decrease because sintering is insufficient (FIGS.", "4-6).", "In each of the examples described above, although each of the performances εr, Qu and τf is excellent individually, balance between each of them is somewhat poor.", "On the other hand, if y is in a range of 0.2 to 0.8 and α is 0.8 % by weight (Nos.", "13-16 in Table 1) and 0.6 by weight (Nos 9-12 in Table 1), εr is excellent.", "Although Qu decreases if α is 0.8% by weight but it is within a range causing no practical problem.", "Further, τf also exhibits a practically sufficient performance with no problem.", "Further, if y is within a range from 0.2 to 0.8 and α is 0.4 % by weight (Nos.", "5 to 8 in Table 1), although εr tends to decrease slightly as compared with the case of α at 0.8 % and 0.6% by weight, Qu is improved greatly and τf is equivalent, to show well balanced excellent performance.", "Furthermore, if y is within a range from 0.2 to 0.8 and a is 0.2% by weight (Nos.", "1-4 in Table 1), each of the characteristics tends to decrease as compared with the case of greater α, but they are within a practically sufficient range (FIGS.", "4 to 6).", "In particular, as shown in results of tables 1 and 2, it is preferred that x is from 0.47 to 0.53, y is from 0.4 to 0.8 and α is from 0.4 to 0.6, since each physical property is balanced.", "In this case, εr may be from 42.9 to 47.7, Qu may be from 790 to 1490 and τf may be from -46.4 to -16.2 ppm/°C.", "Further, it can be seen from FIGS. 4 to 6, that each of the characteristics exhibits a substantially identical trend as y increases from 0.2 to 0.8 irrespective of the value α and, particularly, the performance τf tends to be improved, and the value rf can be controlled within a practical value while maintaining high εr and Qu with no practical problem, by varying the ratio of Nb 2 O 5 and Ta 2 O 5 .", "Example 2 As the raw material in this example, PbO powder (purity: 99.5%) was added further to each of the powder used in Example 1.", "Then, the starting materials were weighed and mixed in the same manner as in Example 1 so as to obtain a composition in which x is 0.6, the addition amount of V 2 O 5 is 0.4% by weight and the addition amount of PbO (δ% by weight) varies within a range from 0 to 2.0 in Bi(NbxTa1-x)O 4 as shown in Table 3.", "In Table 3, x is 0.2 in No. 13, an addition amount of V 2 O 5 is 3.0% by weight in No. 14, and x is 0.2 and an addition amount of V 2 O 5 is 3.0% by weight in No. 15.", "Further, in the same manner as in Example 1, dielectric specimens of identical shape (Nos.", "1 to 30 in Table 3) were obtained and performance evaluation (εr, Qu, τf and sintering density) was carried out.", "The results are also shown in Table 3 and shown in the graphs of FIGS. 7 to 14.", "The sintering products were cleaned after polishing at 80° C. for 30 min and then dried subsequently at 100° C. for 4 hours.", "The resonance frequency upon measurement is as shown in Table 3 (f 0 ).", "τf was measured within a temperature region of 25° to 80° C. and calculated according to τf=(f 80 -f 25 )/(f 25 ×ΔT), and ΔT=80-25=55° C. TABLE 3__________________________________________________________________________ Sinter.", "V.sub[.", "].2 O.sub[.", "].5 PbO Sint.", "temp.", "(α) (δ) f.sub.", "o τ.", "sub.", "f densityNo.", "(°C.) x (wt %) (wt %) (GHz) ε.", "sub.", "r Qu (ppm/°C.) (g/cm.", "sup[.", "].3)__________________________________________________________________________1 850 0.6 0.4 0 Resonance wave form is 6.81 very weak[.", "].2 0.6 0.4 0.2 3.98 42.05 1425 -42.10 7.493 0.6 0.4 0.4 3.83 46.19 1041 -47.22 7.864 0.6 0.4 1 3.83 46.08 487 -58.78 7.705 0.6 0.4 2 3.75 48.06 193 -60.38 7.726 875 0.6 0.4 0 3.85 44.08 1607 -35.91 7.707 0.6 0.4 0.2 3.85 45.43 1640 -39.18 7.798 0.6 0.4 0.4 3.82 46.53 1213 -47.32 7.899 0.6 0.4 1 3.75 48.33 482 -53.06 7.9110 0.6 0.4 2 3.67 50.38 238 -73.80 7.9111 900 0.6 0.4 0 3.85 46.19 1304 -32.82 7.9012 0.6 0.4 0.2 3.83 46.21 1528 -36.67 7.8513 0.2 0.4 0.2 3.85 45.01 1511 -48.21 8.0514 0.6 3.0 0.2 3.80 46.71 735 -42.33 7.9515 0.2 3.0 0.2 3.83 46.40 594 -53.03 8.2316 0.6 0.4 0.4 3.83 46.94 1211 -43.50 7.8917 0.6 0.4 0.6 3.81 47.46 956 -47.80 7.9018 0.6 0.4 0.7 3.80 47.71 828 -49.90 7.9119 0.6 0.4 1 3.76 48.48 445 -56.27 7.9320 0.6 0.4 2 3.65 51.37 280 -83.01 7.9621 925 0.6 0.4 0 3.84 45.93 1255 -31.78 7.6722 0.6 0.4 0.2 3.82 46.36 1423 -39.76 7.8823 0.6 0.4 0.4 3.82 46.58 1192 -45.64 7.8724 0.6 0.4 1 3.75 48.52 458 -56.87 7.9225 0.6 0.4 2 3.64 51.45 240 -104.80 7.9826 950 0.6 0.4 0 3.87 44.87 1214 -33.01 7.6527 0.6 0.4 0.2 3.81 46.16 1378 -39.12 7.8428 0.6 0.4 0.4 3.82 46.46 1094 -44.83 7.8529 0.6 0.4 1 3.75 48.53 407 - 62.61 7.9130 0.6 0.4 2 3.63 51.69 214 106.00 7.97__________________________________________________________________________ From the results, εr is improved from about 45 to about 51 along with increase in the addition amount of PbO irrespective of the sintering temperature except for a case of 42.05 at a sintering temperature of 850° C. and the addition amount of PbO of 0.2% by weight (FIGS.", "7 and 11).", "Improvement of Qu is observed if PbO is added by 0.2% by weight at each of sintering temperature as compared with the case of no addition, but it tends to decrease as the addition amount increases and, particularly, Qu decreases greatly at the addition amount of 1 to 2% by weight (the trend is shown clearly in FIGS. 8 and 12).", "Further, τf tends to increase toward the negative direction along with increase in the addition amount of PbO and the trend is particularly remarkable at the addition amount of 2% by weight (the trend is shown clearly in FIGS. 9 and 13).", "From abovementioned results, it is preferred that x is from 0.2 to 0.9 (tables 1 and 2), the addition amount of V 2 O 5 is from 0.2 to 2.0 part by weight and the addition amount of PbO is from 0.2 to 0.6% by weight (table 3).", "In this case, εr may be from 45 to 48, Qu may be from 960 to 1640 (at from 3.6 to 4.0 GHz) and τf may be from -47 to -32 ppm/°C.", "On the other hand, the sintering density takes a particularly small value in a case where PhO is not added and the sintering temperature is as low as 850° C. In other cases, it slightly increases at each of the sintering temperatures along with the increase in the addition amount of PbO except for a certain case but no remarkable change is observed as a whole (it can be seen also in FIGS. 10 and 14) As described above, while each of the characteristics varies in accordance with the addition amount of PbO and the sintering temperature, each of the characteristics is within a range of causing no practical problem so long as they are within the range of the present invention.", "As a whole, it can he seen that most practically preferred dielectric ceramic compositions are obtained at a sintering temperature of 875° C. or 900° C., with the addition amount of PbO of 0.2 or 0.4% by weight since each of the characteristic is balanced most satisfactorily.", "Further, as can be seen from the results of Nos. 13 to 15, τf tends to increase toward the negative direction if x is as small as 0.2 in the present invention, but dielectric ceramic compositions of excellent characteristics can be obtained according to the present invention within a wide range for x and the addition amount of V 2 O 5 .", "Example 3 For the raw material in this example, MnO 2 powder (purity: 96.0%) was used instead of the PbO powder used in Example 2.", "Then, the raw materials were weighed and mixed in the same manner as in Example 2 so as to obtain compositions in which x Bi(NbxTa 1 -x)O 4 is 0.8, the addition amount of V 2 O 5 is 0.4% by weight and the addition amount of MnO 2 (β% by weight) ranges range from 0 to 2.0.", "In Table x is 0.2 in 4, No. 14, addition amount of V 2 O 5 is 3.0% by weight in No. 15, and x is 0.2 and addition amount of V 2 O 5 is 0.3% by weight in No. 16 in Table 4.", "TABLE 4__________________________________________________________________________ Sinter.", "V.sub[.", "].2 O.sub[.", "].5 MnO.", "sub[.", "].2 Sint.", "temp.", "(α) (β) f.sub.", "o τ.", "sub.", "f densityNo.", "(°C.) x (wt %) (wt %) (GHz) ε.", "sub.", "r Qu (ppm/°C.) (g/cm.", "sup[.", "].3)__________________________________________________________________________1 850 0.8 0.4 0 Resonance wave form is 7.08 very weak[.", "].2 0.8 0.4 0.2 3.84 45.85 1640 -11.61 7.523 0.8 0.4 0.4 3.81 46.83 1176 -9.76 7.524 0.8 0.4 1 3.75 48.62 715 -7.84 7.515 0.8 0.4 2 3.66 50.99 433 -5.50 7.486 875 0.8 0.4 0 3.86 44.45 1757 -18.73 7.477 0.8 0.4 0.2 3.84 46.01 1684 -11.75 7.528 0.8 0.4 0.4 3.82 46.93 1223 -9.91 7.539 0.8 0.4 1 3.75 48.71 729 -10.09 7.5110 0.8 0.4 2 3.65 51.25 449 -8.31 7.4811 900 0.8 0.4 0 3.92 44.60 1485 -18.47 7.4812 0.8 0.4 0.1 3.89 45.17 1574 -14.32 7.4913 0.8 0.4 0.2 3.86 45.74 1662 -10.16 7.5014 0.2 0.4 0.2 3.88 44.72 1482 -53.10 8.1315 0.8 3.0 0.2 3.82 46.31 681 -12.13 7.5516 0.2 3.0 0.2 3.86 45.81 721 -62.31 8.2417 0.8 0.4 0.4 3.83 46.85 1202 -8.34 7.5118 0.8 0.4 0.6 3.80 47.40 1046 -7.81 7.5019 0.8 0.4 0.7 3.79 47.68 968 -7.55 7.5020 0.8 0.4 1 3.75 48.50 734 -6.76 7.4921 0.8 0.4 2 3.65 51.45 476 -8.53 7.4722 925 0.8 0.4 0 3.91 44.78 1319 -19.47 7.3723 0.8 0.4 0.2 3.88 45.12 1680 -11.70 7.4624 0.8 0.4 0.4 3.84 46.37 1163 -8.43 7.4625 0.8 0.4 1 3.77 48.18 721 -9.38 7.4426 0.8 0.4 2 3.65 51.02 445 -10.60 7.4427 950 0.8 0.4 0 3.94 43.75 1245 -19.76 7.2528 0.8 0.4 0.2 3.91 44.09 1668 -13.33 7.3929 0.8 0.4 0.4 3.87 45.35 1181 -10.37 7.3930 0.8 0.4 1 3.80 46.95 710 -9.26 7.3531 0.8 0.4 2 3.67 50.50 418 -12.50 7.35__________________________________________________________________________ Further, in the same manner as in Example 2, dielectric specimens of identical shape (Nos.", "1 to 31 in Table 4) were obtained and performance evaluation (εr, Qu, τf and sintering density) was carried out.", "The resonance frequency upon measurement was as shown in Table 5 (f 0 ).", "The results are shown together in Table 4 and a 1 so shown in the graphs of FIGS. 15 to 22.", "According to the results, τf is extremely poor in a case of not adding MnO 2 and it is improved greatly by the addition of MnO 2 by 0.2% by weight.", "However, although τf tends to the improve a slightly with further increase of the addition amount but shows no great change (in FIG. 17, a curve at β=0 is much different from others, and other curves show no so great difference.", "This can be seen clearly also in FIG. 21).", "Further, εr is improved from about 45 to about 51 along with increase in the addition amount of MnO 2 irrespective of the sintering temperature (FIGS.", "15 and 19).", "Further, although Qu tends to decrease along with increase in the addition amount of MnO 2 in a lower sintering temperature, it reaches a peak at the addition amount of 0.2% by weight as the sintering temperature goes higher and subsequently decreases along with increase the addition amount of MnO 2 (in FIG. 16, curves for β and β=0.2 intersect with each other between 875° C. and 900° C. and Qu at β=0.2 is higher in a high temperature region higher than 900° C. Further, such a trend is also shown in FIG. 20 for the sintering temperature at 900° C.).", "From abovementioned results, it is preferred that x is from 0.2 to 0.9 (table 1 and 2), the addition amount of V 2 O 5 is from 0.2 to 2.0 part by weight (table 4) and the addition amount of MnO 2 is from 0.1 to 0.6 wt % (table 4).", "In this case, εr may be from 45 to 47, Qu may be from 970 to 1640 (at from 3.6 to 3.9 GHz) and τf may be from -14 to -5.5 ppm/°C.", "On the other hand, the sintering density takes a particularly small value if MnO 2 is not added and the sintering temperature is as low as 850° C. In other cases where the sintering temperature is high, the sintering density is improve slightly by the addition amount of MnO 2 of 0.2% by weight at a higher sintering temperature and no remarkable changes is observed with addition amount of MnO 2 .", "Further, the sintering density tends to lower as a whole, as the sintering temperature goes higher (this is shown clearly in FIGS. 18 and 22).", "In this way, each of the characteristics changes variously along with the addition amount of MnO 2 and the sintering temperature, but each of the characteristics lies within a range of causing no practical problem so long as they are within a range of the present invention.", "It can be seen as a whole, that preferred dielectric ceramic compositions well balanced in each of the characteristics can be obtained, particularly, at a sintering temperature of 875° C. or 900° C. and with the addition amount of MnO 2 of 0.2 or 0.4 by weight.", "Further, as can be seen from the results of Nos. 14 to 16, τf tends to increase toward the negative direction if x is as small as 0.2 in the present invention, but dielectric ceramic compositions having practically sufficient characteristics can be obtained in a wide range for x and the addition amount of V 2 O 5 .", "Example 4 For the raw material in this example, TiO 2 powder (purity: 99.9%) was used instead of the PbO powder used in Example 2.", "Then, the starting materials were weighed and mixed in the same manner as in Example 2 so as to obtain a composition in which x in Bi(NbxTa1-x)O4 ranges from 0 to 1.0, the addition amount of V 2 O 5 (α% by weight) ranges from 0 to 3.0 and the addition amount of TiO 2 (τ% by weight) ranges from 0 to 2.0.", "Further, dielectric specimens of identical shape were prepared in same manner as Example 2 (Nos.", "1 to 23 in Table 5) and performance evaluation (εr, Qu, τf and sintering density) was carried out.", "The resonance frequency upon measurement was as shown in Table 5 (f 0 ).", "The results are shown together in Table 5 and also shown in the graphs of FIGS. 23 to 38.", "TABLE 5__________________________________________________________________________ Sinter.", "V.sub[.", "].2 O.sub[.", "].5 TiO.", "sub[.", "].2 Sint.", "temp.", "(α) (γ) f.sub.", "o τ.", "sub.", "f densityNo.", "(°C.) x (wt %) (wt %) (GHz) ε.", "sub.", "r Qu (ppm/°C.) (g/cm.", "sup[.", "].3)__________________________________________________________________________1 900 0.8 0.4 0 3.92 44.60 1485 -18.47 7.482 900 0.8 0.4 0.1 3.40 45.92 1155 -15.81 7.493 900 0.8 0.4 0.2 3.45 47.06 865 -12.24 7.514 900 0.8 0.4 0.4 3.38 47.48 678 -8.96 7.435 900 0.8 0.4 0.6 3.47 46.33 598 -2.38 7.236 900 0.8 0.4 1.0 3.52 43.37 371 10.61 6.897 900 0.8 0.4 2.0 3.54 37.39 251 53.78 6.898 850 0.8 0.4 0.2 Sintering is insufficient[.", "].9 875 0.8 0.4 0.2 3.89 45.43 909 -12.27 7.3610 925 0.8 0.4 0.2 3.40 47.16 838 -10.81 7.5211 950 0.8 0.4 0.2 3.53 47.70 785 -11.76 7.5212 900 0.8 0 0.2 Sintering is insufficient[.", "].13 900 0.8 0.2 0.2 3.47 46.73 839 -13.55 7.5014 900 0.8 1.0 0.2 3.35 47.62 613 -5.51 7.5515 900 0.8 2.0 0.2 3.48 48.18 318 -13.94 7.5316 900 0.8 3.0 0.2 3.60 49.01 185 -21.63 7.5417 900 0 0.4 0.2 3.59 42.03 553 -52.13 8.0818 900 0.2 0.4 0.2 3.53 44.54 512 -55.21 8.1119 900 0.4 0.4 0.2 3.48 46.44 631 -48.03 8.0520 900 0.6 0.4 0.2 3.41 47.21 725 -30.12 7.9021 900 0.7 0.4 0.2 3.43 47.13 795 -21.18 7.7022 900 0.96 0.4 0.2 3.45 46.11 1010 -0.11 7.1523 900 1.0 0.4 0.2 3.23 45.86 1050 2.01 7.05__________________________________________________________________________ The results show that τf improves greatly along with the addition amount of TiO 2 and τf can be controlled easily (FIG.", "25).", "However, since εr and Qu decrease along with addition of TiO 2 (FIGS.", "23 and 24), addition of a great amount of TiO 2 is not preferred.", "Further, if V 2 O 5 is not added (No.", "12), the sintering is insufficient and measurement for each of the characteristics is impossible.", "Then, since εr increases (FIG.", "27) and τf decreases (FIG.", "29) by the addition, τf can be controlled.", "However, since Qu decreases by the addition (FIG.", "28), addition of a great amount of V 2 O 5 is not preferred.", "Further, since τf increases along with increase for the value x in Bi(NbxTa1-x)O 4 (FIG.", "33), τf can be controlled by the change of the value x. Further, since εr and Qu also increase along with this increase (FIGS.", "31 and 32), although it is preferred in view of this physical property, the sintering density is lowered (FIG.", "34).", "7.0 kg/m 3 of sintering density can be ensured even if x is 1.0 (FIG.", "34).", "Further, if the sintering temperature is at 850° C. (No.", "8 in Table 5), sintering is insufficient and measurement for each of the characteristics is impossible.", "On the other hand, at 875° to 950° C. (x=0.8, V 2 O 5 =0.4% by weight, TiO 2 =0.2% by weight), the sintering density is as large as 7.36 to 7.52 kg/m 3 (FIG.", "38) and the physical properties is are also stable (FIGS.", "35-37).", "As described above, while each of the physical properties changes variously in accordance with the addition amounts of V 2 O 5 and TiO 2 and the sintering temperature, each of the characteristics lies within a range causing no practical problem so long as they are within a range of the present invention.", "For instance, in a case where x=0.6 to 0.96, V 2 O 5 =0.2 to 1.0% by weight and TiO 2 =0.1 to 0.6% by weight, τf=-30 to 0 ppm/°C.", ", Qu=610 to 1160, εr=42 to 48.", "In a case where x=0.8 to 0.96, V 2 O 5 =0.4 to 1.0% by weight and TiO 2 =0.2 to 1.0% by weight, εr=43.3 to 47.7, Qu=370 to 910, τf=-13 to +11 ppm/°C.", "Particularly, in a case where x=0.8, V 2 O 5 is 0.4% by weight, TiO 2 =0.2 to 0.4% by weight, εr=45.4 to 47.7, Qu=510 to 910 and τf=-13 to -9 ppm/°C.", ", showing excellent balance of performance.", "As can be seen from the results of Nos. 18 to 20 in Table 5, although τf tends to increase toward the negative direction (-55 to -30 ppm/°C.) if x=as small as 0.2 to 0.6 in the present invention, εr is from 42.0 to 47.2 and Qu is from 510 to 730, which are practically sufficient characteristics.", "Example 5 (1) Preparation of dielectric ceramic composition As the raw material in this example, TiO 2 powder (purity: 99.9%) or PbO powder (purity: 99.5%) was further used in addition to the powder used in Example 3.", "Then, the raw materials were weighted and mixed in the same manner as in Example 3 so as to obtain a composition in which x in Bi(NbxTa1-x)O 4 varies from 0 to 1.0, the addition amount of V 2 O 5 (α% by weight) varies from 0 to 3.0, the addition amount of MnO 2 (β% by weight) varies from 0 to 2.0 and the addition amount of TiO 2 (γ% by weight, shown in Table 6) varies from 0 to 2.0 and, further, the addition amount of PbO (δ% by weight, shown in Table 7) varies from 0 to 2.0, as shown in Table 6 and 7.", "Further, in the same manner as in Example 3, dielectric specimens of identical shape (Nos.", "1 to 27 in Table 6 and Nos. 1 to 29 in Table 7) were obtained and performance evaluation (εr, Qu, τf and sintering density) was carried out.", "The resonance frequency upon measurement was as shown in Tables 6 and 7 (f 0 ).", "The results are shown together in Tables 6 and 7 and also shown in the graphs of FIGS. 39 to 62.", "(2) Effect of examples in V 2 O 5 --MnO 2 --TiO 2 system composition According to the results of Table 6 and FIGS. 39-50 and FIGS. 55 to 62, if V 2 O 5 is not added (No.", "12 in Table 6) sintering is insufficient and measurement for each of the characteristics is impossible.", "Then, since εr increases (FIG.", "39) and τf decreases (FIGS.", "41) along with addition, τf can be controlled.", "However, since Qu decreases along with addition (FIG.", "40), addition of a great amount of V 2 O 5 is not preferred.", "TABLE 6__________________________________________________________________________ Sinter.", "α β γ Sint.", "temp.", "(V.", "sub[.", "].2 O.sub[.", "].5) (MnO.", "sub[.", "].2) (TiO.", "sub[.", "].2) f.sub.", "o τ.", "sub.", "f densityNo.", "(°C.) x (wt %) (wt %) (wt %) (GHz) ε.", "sub.", "r Qu (ppm/°C.) (g/cm.", "sup[.", "].3)__________________________________________________________________________1 900 0.8 0.4 0.2 0 3.86 45.74 1662 -10.16 7.502 900 0.8 0.4 0.2 0.1 3.40 46.40 1493 -8.81 7.513 900 0.8 0.4 0.2 0.2 3.35 47.06 1325 -7.46 7.534 900 0.8 0.4 0.2 0.4 3.38 48.57 747 -1.17 7.505 900 0.8 0.4 0.2 0.7 3.36 48.91 632 6.48 7.366 900 0.8 0.4 0.2 1.0 3.24 49.25 517 14.13 7.227 900 0.8 0.4 0.2 2.0 3.42 46.81 255 50.22 6.678 850 0.8 0.4 0.2 0.2 3.15 46.33 1618 -6.59 7.309 875 0.8 0.4 0.2 0.2 3.19 46.92 1461 -6.78 7.5210 925 0.8 0.4 0.2 0.2 3.33 46.94 1319 -6.30 7.5211 950 0.8 0.4 0.2 0.2 3.31 47.20 1282 -5.44 7.5112 900 0.8 0 0.2 0.2 Sintering is insufficient[.", "].13 900 0.8 0.2 0.2 0.2 3.41 46.63 1227 -10.91 7.5014 900 0.8 1.0 0.2 0.2 3.35 47.88 893 -2.45 7.5615 900 0.8 2.0 0.2 0.2 3.43 48.91 598 -9.03 7.5016 900 0.8 3.0 0.2 0.2 3.41 49.04 417 -16.79 7.4517 900 0.8 0.4 0 0.2 3.45 47.06 865 -12.24 7.5118 900 0.8 0.4 0.4 0.2 3.31 47.23 1438 -6.03 7.5019 900 0.8 0.4 1.0 0.2 3.44 47.46 903 -11.10 7.5020 900 0.8 0.4 1.5 0.2 3.41 47.18 760 -11.46 7.4621 900 0.8 0.4 2.0 0.2 3.40 46.89 618 -11.83 7.4122 900 0 0.4 0.2 0.2 3.31 44.18 884 -48.23 8.0823 900 0.2 0.4 0.2 0.2 3.24 45.90 1023 -49.58 8.1324 900 0.4 0.4 0.2 0.2 3.43 47.16 1211 -44.35 7.9825 900 0.6 0.4 0.2 0.2 3.41 47.51 1203 -25.11 7.7326 900 0.96 0.4 0.2 0.2 3.27 46.02 1389 3.51 7.2127 900 1.0 0.4 0.2 0.2 3.40 45.74 1415 6.34 7.05__________________________________________________________________________ TABLE 7__________________________________________________________________________ Sinter.", "α β δ Sint.", "temp.", "(V.", "sub[.", "].2 O.sub[.", "].5) (MnO.", "sub[.", "].2) (PbO) f.sub.", "o τ.", "sub.", "f densityNo.", "(°C.) x (wt %) (wt %) (wt %) (GHz) ε.", "sub.", "r Qu (ppm/°C.) (g/cm.", "sup[.", "].3)__________________________________________________________________________1 900 0.8 0 0.2 0.2 Sintering is insufficient[.", "].2 900 0.8 0.2 0.2 0.2 3.45 47.80 641 -12.90 7.573 900 0.8 0.3 0.2 0.2 3.44 47.30 1050 -9.60 7.554 900 0.8 0.4 0.2 0.2 3.47 46.81 1465 -6.28 7.535 900 0.8 0.6 0.2 0.2 3.42 46.53 1430 -1.75 7.516 900 0.8 0.8 0.2 0.2 3.47 44.88 1952 -14.46 7.467 900 0.8 1.0 0.2 0.2 3.45 43.75 1842 -23.14 7.428 900 0.8 2.0 0.2 0.2 3.46 42.49 1204 -35.03 7.359 900 0.8 3.0 0.2 0.2 3.40 41.80 513 -44.12 7.4010 850 0.8 0.4 0.2 0.2 3.50 46.98 1523 -16.24 7.4811 875 0.8 0.4 0.2 0.2 3.39 47.13 1468 -11.74 7.5512 925 0.8 0.4 0.2 0.2 3.48 46.89 1388 -13.43 7.5013 950 0.8 0.4 0.2 0.2 3.45 47.04 1399 -10.02 7.5214 900 0.8 0.4 0 0.2 3.40 45.35 1604 -18.04 7.5015 900 0.8 0.4 0.1 0.2 3.46 46.58 1520 -15.47 7.5316 900 0.8 0.4 0.4 0.2 3.35 47.86 1351 -2.07 7.5217 900 0.8 0.4 1.0 0.2 3.46 48.51 1047 -5.34 7.5018 900 0.8 0.4 2.0 0.2 3.45 49.10 798 -12.95 7.5319 900 0.8 0.4 0.2 0 3.86 45.74 1662 -10.16 7.5020 900 0.8 0.4 0.2 0.4 3.65 47.39 1293 -13.24 7.4921 900 0.8 0.4 0.2 0.5 3.36 47.42 1203 -15.70 7.4922 900 0.8 0.4 0.2 1.0 3.54 48.48 753 -28.00 7.4823 900 0.8 0.4 0.2 2.0 3.32 49.25 490 -49.57 7.4524 900 0 0.4 0.2 0.2 3.45 43.81 1050 -44.03 8.0725 900 0.2 0.4 0.2 0.2 3.41 45.99 1223 -48.15 8.0926 900 0.4 0.4 0.2 0.2 3.40 46.75 1335 -39.95 8.0027 900 0.6 0.4 0.2 0.2 3.47 47.01 1421 -23.42 7.7528 900 0.96 0.4 0.2 0.2 3.40 45.89 1503 3.98 7.1229 900 1.0 0.4 0.2 0.2 3.49 45.50 1530 5.15 7.04__________________________________________________________________________ Further, since Qu increases along with addition of MnO 2 up to 0.4% by weight, the addition is effective, but addition of a great amount (1 and 2% by weight) is not preferred because Qu decreases greatly (FIG.", "43).", "It is shown that τf is improved greatly by addition of TiO 2 and τf can be controlled easily (FIG.", "49) Further, addition of TiO 2 up to 1.0% by weight is preferred since εr increases (FIG.", "47).", "Further, since Qu decreases by the addition of TiO 2 and, particularly, Qu decreases remarkably as 747 at 0.4% by weight, addition of a great amount of TiO 2 is not preferred (FIG.", "48).", "Further, since τf increases along with increase of the value x in Bi(NbxTa1-x)O 4 (FIG.", "57), τf can be controlled by the change of the x. Further, since Qu increases along with increase of x (FIG.", "56) and εr also increases with x up to 0.6 (FIG.", "55), it is preferred in view of this physical property, but the sintering density is lowered (FIG.", "58).", "Further, 7.05 kg/m 3 of the sintering density can be insured even if x is 1.0 (No.", "27, FIG. 58).", "Further, sintering is sufficient even at a sintering temperature of 850° C. (No.", "8 in Table 6) and the sintering density is as great as 7.30 to 7.51 kg/m 3 at 850°-950° C. (x=0.8, V 2 O 5 =0.4% by weight, MnO 2 =0.2% by weight and TiO 2 =0.2% by weight) (Nos.", "8 to 11 in Table 6, FIG. 62), and physical properties are also stable (FIGS.", "59 to 62).", "As described above, each of the characteristics changes variously in accordance with the kind of each of the additives, the addition amount thereof and the sintering temperature and well balanced practical performances as shown below are given, for example, with the range of the following compositions according to the results of this example (Table 6).", "(1) At V 2 O 5 : 0.2 to 1.0% by weight, Mn 2 , TiO 2 : both 0.2% by weight and x: 0.8, εr: 46.6 to 47.9, Qu: 890 to 1300, τf: -10.91 to -2.45 ppm/°C.", "(2) At V 2 O 5 : 0.4% by weight, MnO 2 , TiO 2 : both 0.2% by weight and x: 0.8, εr: 47.1, Qu: 1325, τf: -7.46 ppm/°C.", "(3) At MnO 2 : 0.2-1.0% by weight, V 2 O 5 : 0.4% by weight, TiO 2 : 0.2% by weight and x: 0.8, εr: 47.0 to 47.5, Qu: 900 to 1440, τf: -11.1 to -6.0 ppm/°C.", "(4) At TiO 2 : less than 0.4% by weight, V 2 O 5 : 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8, εr: 45.7 to 48.6, Qu: 750 to 1660, τf: -10.2 to -1.1 ppm/°C.", "(5) At TiO 2 : 0.1 to 0.2% by weight, V 2 O 5 : 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8, εr: 46.4 to 47.1, Qu: 1320 to 1490, τf: -8.8 to -7.5 ppm/°C.", "(6) At V 2 O 5 : 0.2 to 1.0% by weight, MnO 2 : not more than 1.0% by weight, TiO 2 : not more than 0.4% by weight and x: 0.8 to 0.96, τf: -12 to +7 ppm/°C.", ", Qu: 800 to 1600, and εr: 45 to 50.", "(3) Effect of the example in V 2 O 5 --MnO 2 --PbO system composition According to the results of Table 7 and FIGS. 39 to 46 and FIGS. 51 to 62, if V 2O 5 is not added (No.", "1 in Table 7), sintering is insufficient and measurement for each of the characteristics is impossible.", "Then, since τf and Qu change by the addition (each in FIGS. 41 and 40), τf and Qu can be controlled.", "Particularly, since τf increases along with the addition up to 0.6% and Qu increases along with addition up to 0.8% by weight, such addition is preferred.", "Further, εr increases along with addition of MnO 2 (FIG.", "43).", "Further, τf increases along with addition up to 0.4% by weight (FIG.", "45).", "Since Qu decreases by the addition, a great amount of addition is not preferred (FIG.", "44).", "Since τf changes along with addition of PbO (mainly in the negative direction), it shows that τf can be controlled easily (FIG.", "53).", "Further, since εr increases with the addition, it is preferred (FIG.", "51).", "Since Qu decreases with the addition, a great amount of addition is not preferred (FIG.", "52).", "Further, since τf changes greatly along with increase of the value x in Bi(NbxTa1-x)O 4 (mainly changes in the positive direction) (FIG.", "57), τf can be controlled by the change of the value x. Further, since Qu increases along with increases of the value x, it is preferred (FIG.", "56).", "While the sintering density tends to lower with the addition, 7.04 kg/m 3 of the sintering density can be ensured even x is 1.0 (No.", "29 in Table 7, FIG. 54).", "Further, referring to the sintering temperature, sufficient sintering is attained at 850° to 950° C. (FIG.", "62) and physical properties are also stable (FIGS.", "59-62).", "Like that in the V 2 O 5 --MnO 2 --TiO 2 system composition.", "As described above, while each of the characteristics changes variously in accordance with the kind of each of the additives, the addition amount thereof and the sintering temperature, the following well balanced practical performances is shown, for example, within a compositional range shown below according to the results of this example (Table 7).", "For instance, the V 2 O 5 --MnO 2 --PbO system compositions exhibit the following well balanced practical performances.", "(1) At V 2 O 5 : 0.4 to 0.8% by weight, MnO 2 and PbO: both 0.2% by weight and x: 0.8, εr: 44.9 to 46.8, Qu: 1460 to 1950, τf: -14.5 to -1.7 ppm/°C.", "(2) At V 2 O 5 : 0.6% by weight, MnO 2 and PbO: both 0.2% by weight and x: 0.8, εr: 46.5, Ou: 1430, τf: -1.75 ppm/°C.", "(3) At MnO 2 : 0.2 to 0.4% by weight, V 2 O 5 : 0.4% by weight, PbO: 0.2% by weight and x: 0.8, εr: 46.8 to 47.9, Qu: 1351 to 1465, τf: -6.3 to -2.1 ppm/°C.", "(4) At PbO: 0.2 to 0.4% by weight, V 2 O 5 : 0.4% by weight, MnO 2 : 0.2% by weight and x: 0.8, εr: 46.8 to 47.4, Qu: 1293 to 1465, τf: -13.2 to -6.3 ppm/°C.", "(5) At V 2 O 5 :0.3 to 0.8% by weight, MnO 2 : 0.1 to 1.0% by weight, PbO: not more than 0.4% by weight and x: 0.8 to 0.96, τf: -15 to +4 ppm/°C.", ", Qu: 1000 to 2000 and εr: 44 to 49.", "The present invention is not restricted to the concrete examples as described above but variously modified embodiment can be made within a scope of the present invention in accordance with the purpose and application uses thereof." ]
CROSS-REFERENCE TO RELATED APPLICATION The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/281,657, filed Nov. 20, 2009. FIELD OF INVENTION The present invention relates in general to air filtration techniques and in particular to ductless cooking air filtration systems and methods. BACKGROUND OF INVENTION Cooking creates undesirable by-products such as smoke and odor that can pollute an inhabited airspace if they are not removed or reclaimed. Consequently, many devices have been invented for addressing the problem of airborne cooking contaminants. For example, ducted range hoods remove the contaminated air from the inhabited area, while ductless range hoods intake air from the cooking area, remove at least some of the contaminants, and then re-circulate the resulting exhaust air back into the inhabited space. Currently available re-circulating (ductless) residential cooking ventilation systems typically rely on an ineffective grease separator and even less effective optional thin odor “filter”. Laboratory testing of these conventional re-circulating systems has indicated that, at best, only a portion of the cooking contaminants are removed from the exhaust air. These conventional systems are particularly ineffective in removing smoke and lingering odors. Furthermore, conventional grease separators and odor filters, when used, block the natural inflow into the range hood “collector” and eliminate necessary capture space. Hence, given the significant disadvantages of currently available cooking ventilation systems, new cooking ventilation apparatus and methods are desirable for removing cooking by-products, including grease, odors, and smoke, from inhabited areas. SUMMARY OF INVENTION The principles of the present invention are embodied in a cooking air recovery system including a housing having a hood for capturing air, grease, and smoke, and an elongated exhaust section in fluid communication with the hood. A grease extracting blower unit takes in air, grease, and smoke through the hood and exhausts air and smoke through the exhaust section of the housing with a substantial amount of the grease removed by centrifugal force. A charcoal filter disposed in the exhaust section removes odors from the air exhausted from the grease extracting blower unit and a smoke filter removes smoke from the air passed through the charcoal filter. Embodiments of the present principles realize substantial advantages over the prior art. Among other things, an unobstructed hood, without screens or filters at the hood aperture, allows for smoke, grease, and odor to be efficiently captured and passed to the centrifugal blower-separator. The centrifugal blower—grease extractor in turn liquefies and removes grease from the air flow and deposits it in a pan for easy disposal. Furthermore, by removing a substantial portion of the grease, the centrifugal blower—extractor ensures that the media in the following charcoal filter is not contaminated. A thick, heavy charcoal filter advantageously ensures that the exhaust air flow remains in contact with the activated filter media for a sufficiently long period of time to remove odor. Finally, a high-density filter with a large contact area removes smoke from the exhaust air flow. BRIEF DESCRIPTION OF DRAWINGS For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: FIG. 1 is a diagram of a representative duct-free cooking air filtration system, embodying the principles of the present invention, shown in a typical home cooking environment; FIG. 2A is a diagram providing a prospective view of the duct-free air filtration system of FIG. 1 ; FIG. 2B is a diagram providing a partially exploded view of the duct-free air filtration system shown in FIG. 1 ; FIG. 3A is a diagram providing a cut-away view of the duct air filtration system of FIG. 1 ; FIG. 3B is a conceptual diagram of a conventional ductless hood system; and FIG. 4 is a diagram of the blower-grease extractor assembly of the duct-free air filtration system of FIG. 1 . DETAILED DESCRIPTION OF THE INVENTION The principles of the present invention and their advantages are best understood by referring to the illustrated embodiment depicted in FIGS. 1-4 of the drawings, in which like numbers designate like parts. FIG. 1 is a diagram of an exemplary duct-free hood system 100 embodying the principles of the present invention. Duct-free hood system 100 is shown disposed over a conventional home kitchen stove 101 , which during normal cooking generates cooking byproducts including grease, odors, and smoke. While duct-free hood system 100 is shown the preferred home kitchen environment, the present inventive principles are not limited thereto, and may be applied to other environments, such as commercial kitchens. In addition to stoves, the cooking byproducts can be generated by other cooking appliances, such as frying pans and similar electric apparatus. FIG. 2A is line drawing showing the internal structures of duct-free hood system 100 . In particular, duct-free hood system 100 includes a hood 201 , which provides a wide-open aperture, without obstructing screens or filters, for receiving intake air flow containing cooking byproducts. Hood 201 and/or exhaust housing 203 are constructed from stainless steel, glass, or a similar material that is sufficiently rugged yet provides for an ornamental design. Intake air flow is inducted by a centrifugal blower-grease extractor 202 , which in the illustrated embodiment is constructed and operates in accordance with co-assigned U.S. Pat. No. 6,820,609 to Woodall, I I I et al. for Low-profile Ventilation Hood. The exhaust air discharged from centrifugal blower-grease extractor 202 is passed into exhaust housing 203 of duct-free hood system 100 towards exhaust vents 204 a - 204 b . Exhaust housing 203 includes a thick odor removing activated charcoal filter 205 and a pleated fiber smoke filter 206 . As shown in the exploded view of FIG. 2B , activated charcoal filter 205 and smoke filter 206 are preferably discrete units, which can be removed from exhaust housing 203 for servicing or replacement. In the illustrated embodiment, activated charcoal filter 205 is constructed of a double layered squared off inverted “U” shaped chamber made of perforated metal enclosed in a sheet metal box-shaped housing that is open top and bottom. Between the double layers of perforated metal is a one (1) inch thick bed of activated carbon pellets. (Other types of odor filtering media may be used in alternate embodiments.) The squared off inverted “U” shaped carbon bed advantageously maximizes the exposure time of the exhaust air stream to the carbon pellets within the space constraints. Odor removal effectiveness increases with the time the contaminated air is in contact with the actuated charcoal and this design generates carbon pellet to exhaust air stream exposure approximately fifty (50) times longer than existing carbon thin mat filters. For example, for an embodiment of the present invention in which blower-grease extractor 202 provides an exhaust air flow of approximately 200 cubic feet per minute (cfm) and charcoal filter 205 provides approximately 221 cubic inches (cubic in.) of charcoal pellets, the exhaust air stream exposure ratio is approximately 220 cfm/231 cubic in or 0.85 cfm/cubic in. (The performance of charcoal filter 205 can be improved by reducing the cfm/cubic in. ratio or reduced by increasing the cfm/cubic in, as needed for the particular embodiment). Smoke filter 206 , in the illustrated embodiment, mounts directly on the open top of the box shaped charcoal filter housing of charcoal filter 206 . This configuration forces all of the air flowing through the activated carbon bed into smoke filter 206 . Preferably, smoke filter 206 includes a filter element constructed of thin layer glass media folded into a multi-pleated pattern to maximize filter surface area within the space constraints. In the illustrated embodiment, the filter media is rated to trap 95 percent of particles measuring three microns and larger that enter the filter. Other ratings from 60 percent of particles measuring three microns and larger to 99.97 percent of particles measuring three microns and larger can also be utilized. (The smoke particles are permanently trapped within the filter element because they are larger than the openings in the filter media.) For an exhaust air flow of approximately 200 cfm, and a filter media providing approximately 35 square feet of surface area, the exhaust air stream exposure ratio is 200 cfm/35 sq. ft. or 5.5 cfm/sq. ft. (The performance of smoke filter can be increased by reducing the cfm/sq. ft. ratio, or reduced by reducing the cfm/sq. ft. ratio, as required by the particular embodiment. The four-phase air recovery process implemented by duct-free hood system 100 is illustrated in FIG. 3A . The first and second phases are implemented by blower-grease extractor 202 , which is shown in further detail in FIG. 4 . In particular, blower-grease extractor includes a centrifugal blower 401 , circular intake aperture 402 , sidewalls 403 , grease pan 404 , and laterally offset exhaust aperture 405 . A complete description of blower-grease extractor 202 is provided in co-assigned U.S. Pat. No. 6,820,609, incorporated herein by reference. In the first phase, a centrifugal blower 401 achieves active canopy collection by pulling air from hood (canopy) 201 in through intake aperture 402 . The wide-open design of hood canopy 201 allows blower-grease extractor 202 to efficiently capture the rising cooking byproducts from the underlying cooking appliance. For the second phase, a temperature sensor ensures that blower 401 is operating at the optimum speed for centrifugal grease extraction. Such a temperature sensor is disclosed in co-assigned U.S. Pat. No. 6,142,142, also incorporated herein by reference. As the dirty air passes through aperture 402 , the grease is separated from the air as the air undergoes rapid radial acceleration. The grease is then gravity collected in grease collection pan 404 while the grease-free air passes through laterally offset exhaust aperture 405 . In the third phase, the air stream exhausted from blower-grease extractor 202 is passed through charcoal odor filter 205 , discussed in detail above. Finally, in the fourth phase, the air stream is passed through smoke filter 206 and out of exhaust vents 204 a and 204 b. In additional embodiments of the principles of the present invention, apparatus may be provided within hood 201 or exhaust housing 203 for releasing an odor masking agent, freshening aroma, or disinfectant. A reactive device, such as an ultraviolet light source, may also be provided for killing bacteria, viruses, and other pathogens. The illustrated embodiment of the present principles is contrasted with a conventional ductless ventilation hood 300 in FIG. 3A . As shown in FIG. 3A , the conventional system includes a restricted canopy 302 having a limited capability to capture cooking byproducts generated on the underlying cooking equipment (not shown). In particular, the aperture of canopy 302 is obstructed by a conventional filter system 303 formed by metal baffles and/or a thin layer of filter material. The metal baffles and/or thin layer of filter material are not only ineffective in stopping grease, smoke, and odors, from flowing through but also are difficult to remove and clean of those cooking byproducts that are captured. Conventional ventilation system 300 utilizes a simply blower 301 for inducing air flow through the system housing. Blower 301 does not extract any of the grease that has passed through filter 303 and simply exhausts that grease back into the surrounding environment. Conventional ventilation system 300 does not include a thick charcoal filter for removing odors or a smoke filter for removing smoke pulled-in in from the stove. In sum, the principles of the present invention are embodied in robust apparatus and methods for removing airborne cooking byproducts, including grease, odor, and smoke. These embodiments include a wide-open hood (canopy) and a centrifugal blower-grease extractor, which efficiently capture the cooking byproducts and remove grease. A thick odor filter ensures that the airstream exhausted from the blower-grease extractor is sufficiently exposed to the active filter material such that odors are substantially removed. A smoke filter, having a pleated-material filter element with a large surface area, ensures that smoke is substantially removed from the air stream. Although the invention has been described with reference to specific embodiments, these descriptions are not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed might be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. It is therefore contemplated that the claims will cover any such modifications or embodiments that fall within the true scope of the invention.
A duct-free air filtration system including a housing having a hood for capturing air, grease, and smoke, and an elongated exhaust section in fluid communication with the hood. A grease extracting blower unit takes in air, grease, and smoke through the hood and exhausts air and smoke through the exhaust section of the housing with a substantial amount of the grease removed by centrifugal force. A charcoal filter disposed in the exhaust section removes odors from the air exhausted from the grease extracting blower unit and a smoke filter removes smoke from the air passed through the charcoal filter.
Identify and summarize the most critical features from the given passage.
[ "CROSS-REFERENCE TO RELATED APPLICATION The present application claims the benefit of U.S. Provisional Patent Application Ser.", "No. 61/281,657, filed Nov. 20, 2009.", "FIELD OF INVENTION The present invention relates in general to air filtration techniques and in particular to ductless cooking air filtration systems and methods.", "BACKGROUND OF INVENTION Cooking creates undesirable by-products such as smoke and odor that can pollute an inhabited airspace if they are not removed or reclaimed.", "Consequently, many devices have been invented for addressing the problem of airborne cooking contaminants.", "For example, ducted range hoods remove the contaminated air from the inhabited area, while ductless range hoods intake air from the cooking area, remove at least some of the contaminants, and then re-circulate the resulting exhaust air back into the inhabited space.", "Currently available re-circulating (ductless) residential cooking ventilation systems typically rely on an ineffective grease separator and even less effective optional thin odor “filter.”", "Laboratory testing of these conventional re-circulating systems has indicated that, at best, only a portion of the cooking contaminants are removed from the exhaust air.", "These conventional systems are particularly ineffective in removing smoke and lingering odors.", "Furthermore, conventional grease separators and odor filters, when used, block the natural inflow into the range hood “collector”", "and eliminate necessary capture space.", "Hence, given the significant disadvantages of currently available cooking ventilation systems, new cooking ventilation apparatus and methods are desirable for removing cooking by-products, including grease, odors, and smoke, from inhabited areas.", "SUMMARY OF INVENTION The principles of the present invention are embodied in a cooking air recovery system including a housing having a hood for capturing air, grease, and smoke, and an elongated exhaust section in fluid communication with the hood.", "A grease extracting blower unit takes in air, grease, and smoke through the hood and exhausts air and smoke through the exhaust section of the housing with a substantial amount of the grease removed by centrifugal force.", "A charcoal filter disposed in the exhaust section removes odors from the air exhausted from the grease extracting blower unit and a smoke filter removes smoke from the air passed through the charcoal filter.", "Embodiments of the present principles realize substantial advantages over the prior art.", "Among other things, an unobstructed hood, without screens or filters at the hood aperture, allows for smoke, grease, and odor to be efficiently captured and passed to the centrifugal blower-separator.", "The centrifugal blower—grease extractor in turn liquefies and removes grease from the air flow and deposits it in a pan for easy disposal.", "Furthermore, by removing a substantial portion of the grease, the centrifugal blower—extractor ensures that the media in the following charcoal filter is not contaminated.", "A thick, heavy charcoal filter advantageously ensures that the exhaust air flow remains in contact with the activated filter media for a sufficiently long period of time to remove odor.", "Finally, a high-density filter with a large contact area removes smoke from the exhaust air flow.", "BRIEF DESCRIPTION OF DRAWINGS For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: FIG. 1 is a diagram of a representative duct-free cooking air filtration system, embodying the principles of the present invention, shown in a typical home cooking environment;", "FIG. 2A is a diagram providing a prospective view of the duct-free air filtration system of FIG. 1 ;", "FIG. 2B is a diagram providing a partially exploded view of the duct-free air filtration system shown in FIG. 1 ;", "FIG. 3A is a diagram providing a cut-away view of the duct air filtration system of FIG. 1 ;", "FIG. 3B is a conceptual diagram of a conventional ductless hood system;", "and FIG. 4 is a diagram of the blower-grease extractor assembly of the duct-free air filtration system of FIG. 1 .", "DETAILED DESCRIPTION OF THE INVENTION The principles of the present invention and their advantages are best understood by referring to the illustrated embodiment depicted in FIGS. 1-4 of the drawings, in which like numbers designate like parts.", "FIG. 1 is a diagram of an exemplary duct-free hood system 100 embodying the principles of the present invention.", "Duct-free hood system 100 is shown disposed over a conventional home kitchen stove 101 , which during normal cooking generates cooking byproducts including grease, odors, and smoke.", "While duct-free hood system 100 is shown the preferred home kitchen environment, the present inventive principles are not limited thereto, and may be applied to other environments, such as commercial kitchens.", "In addition to stoves, the cooking byproducts can be generated by other cooking appliances, such as frying pans and similar electric apparatus.", "FIG. 2A is line drawing showing the internal structures of duct-free hood system 100 .", "In particular, duct-free hood system 100 includes a hood 201 , which provides a wide-open aperture, without obstructing screens or filters, for receiving intake air flow containing cooking byproducts.", "Hood 201 and/or exhaust housing 203 are constructed from stainless steel, glass, or a similar material that is sufficiently rugged yet provides for an ornamental design.", "Intake air flow is inducted by a centrifugal blower-grease extractor 202 , which in the illustrated embodiment is constructed and operates in accordance with co-assigned U.S. Pat. No. 6,820,609 to Woodall, I I I et al.", "for Low-profile Ventilation Hood.", "The exhaust air discharged from centrifugal blower-grease extractor 202 is passed into exhaust housing 203 of duct-free hood system 100 towards exhaust vents 204 a - 204 b .", "Exhaust housing 203 includes a thick odor removing activated charcoal filter 205 and a pleated fiber smoke filter 206 .", "As shown in the exploded view of FIG. 2B , activated charcoal filter 205 and smoke filter 206 are preferably discrete units, which can be removed from exhaust housing 203 for servicing or replacement.", "In the illustrated embodiment, activated charcoal filter 205 is constructed of a double layered squared off inverted “U”", "shaped chamber made of perforated metal enclosed in a sheet metal box-shaped housing that is open top and bottom.", "Between the double layers of perforated metal is a one (1) inch thick bed of activated carbon pellets.", "(Other types of odor filtering media may be used in alternate embodiments.) The squared off inverted “U”", "shaped carbon bed advantageously maximizes the exposure time of the exhaust air stream to the carbon pellets within the space constraints.", "Odor removal effectiveness increases with the time the contaminated air is in contact with the actuated charcoal and this design generates carbon pellet to exhaust air stream exposure approximately fifty (50) times longer than existing carbon thin mat filters.", "For example, for an embodiment of the present invention in which blower-grease extractor 202 provides an exhaust air flow of approximately 200 cubic feet per minute (cfm) and charcoal filter 205 provides approximately 221 cubic inches (cubic in.) of charcoal pellets, the exhaust air stream exposure ratio is approximately 220 cfm/231 cubic in or 0.85 cfm/cubic in.", "(The performance of charcoal filter 205 can be improved by reducing the cfm/cubic in.", "ratio or reduced by increasing the cfm/cubic in, as needed for the particular embodiment).", "Smoke filter 206 , in the illustrated embodiment, mounts directly on the open top of the box shaped charcoal filter housing of charcoal filter 206 .", "This configuration forces all of the air flowing through the activated carbon bed into smoke filter 206 .", "Preferably, smoke filter 206 includes a filter element constructed of thin layer glass media folded into a multi-pleated pattern to maximize filter surface area within the space constraints.", "In the illustrated embodiment, the filter media is rated to trap 95 percent of particles measuring three microns and larger that enter the filter.", "Other ratings from 60 percent of particles measuring three microns and larger to 99.97 percent of particles measuring three microns and larger can also be utilized.", "(The smoke particles are permanently trapped within the filter element because they are larger than the openings in the filter media.) For an exhaust air flow of approximately 200 cfm, and a filter media providing approximately 35 square feet of surface area, the exhaust air stream exposure ratio is 200 cfm/35 sq.", "ft.", "or 5.5 cfm/sq.", "ft.", "(The performance of smoke filter can be increased by reducing the cfm/sq.", "ft.", "ratio, or reduced by reducing the cfm/sq.", "ft.", "ratio, as required by the particular embodiment.", "The four-phase air recovery process implemented by duct-free hood system 100 is illustrated in FIG. 3A .", "The first and second phases are implemented by blower-grease extractor 202 , which is shown in further detail in FIG. 4 .", "In particular, blower-grease extractor includes a centrifugal blower 401 , circular intake aperture 402 , sidewalls 403 , grease pan 404 , and laterally offset exhaust aperture 405 .", "A complete description of blower-grease extractor 202 is provided in co-assigned U.S. Pat. No. 6,820,609, incorporated herein by reference.", "In the first phase, a centrifugal blower 401 achieves active canopy collection by pulling air from hood (canopy) 201 in through intake aperture 402 .", "The wide-open design of hood canopy 201 allows blower-grease extractor 202 to efficiently capture the rising cooking byproducts from the underlying cooking appliance.", "For the second phase, a temperature sensor ensures that blower 401 is operating at the optimum speed for centrifugal grease extraction.", "Such a temperature sensor is disclosed in co-assigned U.S. Pat. No. 6,142,142, also incorporated herein by reference.", "As the dirty air passes through aperture 402 , the grease is separated from the air as the air undergoes rapid radial acceleration.", "The grease is then gravity collected in grease collection pan 404 while the grease-free air passes through laterally offset exhaust aperture 405 .", "In the third phase, the air stream exhausted from blower-grease extractor 202 is passed through charcoal odor filter 205 , discussed in detail above.", "Finally, in the fourth phase, the air stream is passed through smoke filter 206 and out of exhaust vents 204 a and 204 b. In additional embodiments of the principles of the present invention, apparatus may be provided within hood 201 or exhaust housing 203 for releasing an odor masking agent, freshening aroma, or disinfectant.", "A reactive device, such as an ultraviolet light source, may also be provided for killing bacteria, viruses, and other pathogens.", "The illustrated embodiment of the present principles is contrasted with a conventional ductless ventilation hood 300 in FIG. 3A .", "As shown in FIG. 3A , the conventional system includes a restricted canopy 302 having a limited capability to capture cooking byproducts generated on the underlying cooking equipment (not shown).", "In particular, the aperture of canopy 302 is obstructed by a conventional filter system 303 formed by metal baffles and/or a thin layer of filter material.", "The metal baffles and/or thin layer of filter material are not only ineffective in stopping grease, smoke, and odors, from flowing through but also are difficult to remove and clean of those cooking byproducts that are captured.", "Conventional ventilation system 300 utilizes a simply blower 301 for inducing air flow through the system housing.", "Blower 301 does not extract any of the grease that has passed through filter 303 and simply exhausts that grease back into the surrounding environment.", "Conventional ventilation system 300 does not include a thick charcoal filter for removing odors or a smoke filter for removing smoke pulled-in in from the stove.", "In sum, the principles of the present invention are embodied in robust apparatus and methods for removing airborne cooking byproducts, including grease, odor, and smoke.", "These embodiments include a wide-open hood (canopy) and a centrifugal blower-grease extractor, which efficiently capture the cooking byproducts and remove grease.", "A thick odor filter ensures that the airstream exhausted from the blower-grease extractor is sufficiently exposed to the active filter material such that odors are substantially removed.", "A smoke filter, having a pleated-material filter element with a large surface area, ensures that smoke is substantially removed from the air stream.", "Although the invention has been described with reference to specific embodiments, these descriptions are not meant to be construed in a limiting sense.", "Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention.", "It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed might be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention.", "It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.", "It is therefore contemplated that the claims will cover any such modifications or embodiments that fall within the true scope of the invention." ]
BACKGROUND OF THE INVENTION [0001] This invention generally relates to compressing digital video data, and more specifically, to methods and systems using MPEG standards for compressing such data. [0002] Full motion video displays based upon analog video signals have long been available in the form of television. With recent increases in computer processing capabilities and affordability, full motion video displays based upon digital video signals are becoming more widely available. Digital video systems can provide significant improvements over conventional analog video systems in creating, modifying, transmitting, storing, and playing full motion video sequences. [0003] Digital video displays include large numbers of image frames that are played or rendered successively at frequencies of between 30 and 75 Hz. Each image frame is a still image formed from an array of pixels according to the display resolution of a particular system. As examples, VHS based systems have display resolutions of 320×480 pixels, NTSC based systems have display resolutions of 720×486 pixels, and high-definition television (HDTV) systems have display resolutions of 1360×1024 pixels. [0004] The amounts of raw digital information included in video sequences are massive. The storage and transmission of these massive amounts of video information is infeasible with conventional personal computer equipment. For instance, a two hour full length motion picture, shown in VHS image format, may have 100 gigabytes of digital information. [0005] In response to the limitations in storing or transmitting such massive amounts of digital video information, various video compression standards or processes have been established, including MPEG-1 and MPEG-2. These conventional video compression techniques utilize similarities between successive image frames, referred to as temporal or interframe correlation, to provide interframe compression in which pixel based representations of image frames are converted to motion representations. In addition, the conventional video compression techniques use similarities within image frames, referred to as spatial or intraframe correlation, to provide intraframe compression in which the motion representations within an image frame are further compressed. Intraframe compression is based upon conventional processes for compressing still images, such as discrete cosine transform (DCT) encoding. [0006] The MPEG standard provides interframe and intraframe compression based upon square blocks or arrays of pixels in video images. A video image is divided into macroblocks having dimensions of 16×16 pixels. Each macroblock 16×16 is broken into 4 8×8 luminances blocks and 2 or 4 8×8 chrominance blocks. For each macroblocks T n in an image frame N, a search is performed across the image of the next successive video frame N+1 or an immediately preceding image frame N−1 (i.e., bidirectionally) to identify the most similar respective macroblocks T N+1 or T N−1 . [0007] In an ideal case, the pixels in macroblocks T N and T N+1 are identical, even if the macroblocks have different positions in their respective image frames. Under these circumstances, the pixel information in macroblocks T N+1 is redundant to that in macroblocks T N . Compression is achieved by substituting the positional translation between macroblocks T N and T N+1 . In this simplified example, a single translation vector (Δx, Δy) is designated for the video information associated with the 256 pixels in macroblocks T N+1 . [0008] With prior art MPEG compression, or encoding, routines, each macroblocks of pixels, or coefficients, is encoded by a variable length encoding (VLE) unit, and then sent to a compressed output interface as part of an encoded bitstream. In constant bitrate (CBR) encoding, the average compressed output, which consists of headers plus VLE unit output, must match a user selected bitrate. The encoding system translates the bitrate into target bits per picture and subsequently into target bits per block. The bits used by the headers are predictable, but the bits used by the VLE unit output are variable. If the VLE unit passes the first N bits of its output per block, where N is the target bits per block, then a constant bitrate can be achieved. If the number of bits being used per block is known in advance, the speed of the encoding process can be increased by eliminating the time needed to wait for the actual number of bits to be reported. A sophisticated look-ahead bit production scheme is needed to accomplish this. SUMMARY OF THE INVENTION [0009] An object of this invention is to encode a digital video picture to an exact size, in terms of number of bits, using an MPEG digital encoder in real-time. [0010] Another object of this invention is to provide an encoding method and system that may be used to help maintain an exact bitrate while encoding digital video in real-time. [0011] These and other objectives are obtained with a method and system for encoding digital video picture data. In accordance with this method, the video picture data is partitioned into a group of blocks, at least some of those blocks are selected, one block at a time, and each of the selected blocks of data is encoded to form encoded coefficients having an associated number of bits. The encoded coefficients are outputted, and an accumulated sum of the number of bits in the outputted encoded coefficients is kept. The outputting of the encoded coefficients is terminated at a defined time in order to prevent the accumulated sum from exceeding a given number. [0012] Preferably, the group of blocks that are partitioned from the video picture data, have a defined order, and the selected blocks are encoded in this defined order. Also, with this preferred arrangement, after each time one of the encoded coefficients is outputted, a look-ahead sum is determined by adding (1) the above-mentioned accumulated sum, and (2) the number of bits in the encoded coefficient next in the defined order within the block. The outputting of the encoded coefficients is terminated when that look-ahead sum is greater than the given number. [0013] Further benefits and advantages of the invention will become apparent from a consideration of the following detailed description, given with reference to the accompanying drawing, which specifies and shows a preferred embodiment of the invention. BRIEF DESCRIPTION OF THE DRAWING [0014] The sole FIGURE in the drawing is a block diagram of a digital video picture encoder. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0015] The FIGURE is a block diagram of an MPEG encoder. An input video signal contains pixel data for a video frame, and this frame data are stored in the current frame memory 12 . This frame data is passed both to a reference frame memory 14 and to a sampling circuit 16 . The frame data stored in the reference frame memory 14 is used as reference data in the motion estimation process, discussed below. [0016] There are two modes of processing frame data: an intra-coded mode, and a predictive coded mode. In the intra-coded mode, each frame is coded using information only from the frame itself; and in the predictive coded mode, each frame is coded using motion compensation predicted from a part of a previous coded frame. In practice, most of the frames are coded using the predictive-coding mode. [0017] Block sampling circuit 16 receives the data stored in the current frame memory 12 and partitions the frame data into spatially non-overlapping blocks of pixel data. To provide a reasonable level of adaptiveness, a block size of 8×8 pixels may be used. Switch 20 selectively delivers the output blocks of pixel data from the block sampling circuit 16 either to a line 22 for intra-coded processing or to a line 24 for predictive coded processing. [0018] For the intra-coded mode, the output of circuit 16 is transmitted to a discrete cosine transform (DCT) circuit 26 . Circuit 26 performs a discrete cosine transform, which is a popular mathematical transformation for converting image data to data in the frequency domain. The transformed data are then subjected to a quantization process in a quantization circuit 30 using a quantizer matrix and a quantizer step size that is provided by a rate controller 32 . The quantized data is then transmitted to a run length coding and variable length coding circuit 34 , which performs run-length and variable length coding of the quantized data. The output of the circuit 34 is a coded bit stream ready to be transmitted to a decoder. [0019] This bit stream is also passed to the rate controller 32 . Based on the number of bits already used at the time of encoding the block, the rate controller 32 adjusts the quantizer step so that the output bit stream satisfies the bit rate requirement of the encoder system. The quantized values obtained by circuit 30 are also passed to inverse circuits 36 . These circuits reverse both the quantization performed by circuit 30 and the transform performed by circuit 26 to obtain reconstructed data. This reconstructed data is stored in memory 40 and may be used for the motion compensation process of the next input frame. [0020] For the predictive-coding mode, the output of the block sampling circuit 16 is applied to a motion vector circuit 42 . This circuit compares the current frame with a previous frame stored in memory 14 to determine motion vectors. This circuit outputs the obtained motion vectors together with the blocks of pixels supplied from sampling circuit 16 . [0021] This output is applied to a motion compensation circuit 44 , which may perform motion compensation using the blocks stored in the local frame memory 40 as reference blocks. Circuit 44 generates either a differential block (coded with motion compensation) or the original block (coded without motion compensation). Circuit 44 also generates a bit indicating whether the block is coded with or without motion compensation. This data generated by circuit 44 is applied to DCT circuit 26 and then to circuits 30 and 34 , and this latter circuit outputs the coded bit stream ready for transmission to the decoder. [0022] With prior art MPEG encoders, each 8×8 block of coefficients is encoded by the VLE unit 34 and sent to the compressed output interface as part of the encoded bitstream. Each encoded coefficient is variable in length. The variable-length code is selected based on the value of the given quantized DCT coefficient and its distance from the previous non-zero coefficient in the block as determined by a predefined block scanning order. Therefore, the actual encoded size of an 8×8 block, in terms of number of bits, is unknown until after each coefficients's variable-length code has been determined within the VLE unit. [0023] In accordance with the present invention, a digital video picture is encoded to an exact size by calculating and setting a bit limit per block in the VLE unit 34 . This limit is calculated and set by microcode, schematically represented at 46 . This bit limit is used in conjunction with the bitrate control algorithm and the bits per picture target to encode pictures to a predetermined size. Also, preferably, this bit limit can be adjusted dynamically by the microcode. [0024] More specifically ,as represented by block 50 , the VLE unit 34 accumulates a sum of the total number of bits used per block while receiving the quantized DCT coefficients as input and outputting the variable-length code. Also, the VLE unit, as schematically represented by block 52 , compares the accumulated number of used bits with the block limit value set by the microcode, and the VLE terminates its output of variable-length code for a given block when that accumulated number of used bits reaches the limit. [0025] The VLE unit then discards the remaining coefficients of the block and finishes its encoding of the block by outputting an end of block (EOB) code. This produces a valid (according to the MPEG standard) encoded block with the discarded coefficients being implicitly encoded as coefficients with the value of zero. Because of the nature of the DCT transform and quantization used by MPEG encoding, in many, if not most instances, these coefficients would have been zero or a low value even if they were not discarded. The coefficients that are discarded from the end of the block are the high frequency coefficients that have the least effect on visual picture quality. [0026] Part of the dynamics of this overall mechanism stems from the fact that the encoder uses variable-length codes and does not always reach the limit exactly. Preferably, any variable-length code produced is included in the encoded bitstream in its entirety. In order to accomplish this, the VLE unit 34 looks ahead one coefficient to determine if the next coefficient's variable-length code will cause the accumulated block sum to exceed the block limit. If it will exceed that limit, the VLE unit terminates the block as described above. If it will not exceed the limit, the VLE unit outputs the variable-length code and looks to the next coefficient and so on. In this way, the block limit is never exceeded, but many times it is not reached. When it is not reached exactly, the microcode recognizes this from the bit count that the VLE unit reports, and adjusts the block limit for the next block accordingly in order to use up the allocated bits per picture. By the time the last block of a picture is encoded, the predetermined picture size will be met. [0027] In the preferred implementation, the microcode 46 sets the VLE block limits on a per macroblock basis. The microcode sets two limit values. One limit is used for luminance blocks, and the other is used for chrominance blocks. This allows for the capability of using more bits for the luminance blocks and less for the chrominance blocks or vice versa. With alternative implementations, a different limit may be set for each block of a macroblock, or a new block limit may be provided for each block after adjusting for unused bits. [0028] The present invention is an alternative to a quantization constraining mechanism, described in the prior art, that predetermines that a set number of coefficients will be “zeroed” out. This mechanism can not be used effectively to meet exact picture sizes because it is used prior to the VLE unit in the encoding process. Since it is used prior to the VLE unit, it can not know the final output size, which is determined by the variable-length codes. In addition, it may be blanketing out coefficients that are not necessary (i.e., the encoded blocks may be small even without the constraining, making the constraining unnecessary and most likely detrimental to picture quality). [0029] With the block limit solution used in the present invention, the remainder of the block is only zeroed out if the encoded size of the block has reached the limit. Therefore, blocks with encoded sizes smaller than the limit will be encoded and included in the encoded bitstream in their entirety. Picture quality is not compromised to the unacceptable extent of the prior art quantization constraining mechanism. [0030] The method and system disclosed herein is useful in many digital video encoding applications. Because its intent is to encode a picture to an exact size, it is an important function for the application of video splicing and editing. It is also used in normal real-time encoding in conjunction with the encoder's bitrate algorithm to meet picture targets that are calculated. [0031] While the invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.
A method and system for encoding digital video picture data. In accordance with this method, the video picture data is partitioned into a group of blocks, at least some of those blocks are selected, one block at a time, and each of the selected blocks of data is encoded to form an encoded coefficient having an associated number of bits. The encoded coefficients are outputted, and an accumulated sum of the number of bits in the outputted encoded coefficients is kept. The outputting of the encoded coefficients is terminated at a defined time in order to prevent the accumulated sum from exceeding a given number.
Summarize the document in concise, focusing on the main idea's functionality and advantages.
[ "BACKGROUND OF THE INVENTION [0001] This invention generally relates to compressing digital video data, and more specifically, to methods and systems using MPEG standards for compressing such data.", "[0002] Full motion video displays based upon analog video signals have long been available in the form of television.", "With recent increases in computer processing capabilities and affordability, full motion video displays based upon digital video signals are becoming more widely available.", "Digital video systems can provide significant improvements over conventional analog video systems in creating, modifying, transmitting, storing, and playing full motion video sequences.", "[0003] Digital video displays include large numbers of image frames that are played or rendered successively at frequencies of between 30 and 75 Hz.", "Each image frame is a still image formed from an array of pixels according to the display resolution of a particular system.", "As examples, VHS based systems have display resolutions of 320×480 pixels, NTSC based systems have display resolutions of 720×486 pixels, and high-definition television (HDTV) systems have display resolutions of 1360×1024 pixels.", "[0004] The amounts of raw digital information included in video sequences are massive.", "The storage and transmission of these massive amounts of video information is infeasible with conventional personal computer equipment.", "For instance, a two hour full length motion picture, shown in VHS image format, may have 100 gigabytes of digital information.", "[0005] In response to the limitations in storing or transmitting such massive amounts of digital video information, various video compression standards or processes have been established, including MPEG-1 and MPEG-2.", "These conventional video compression techniques utilize similarities between successive image frames, referred to as temporal or interframe correlation, to provide interframe compression in which pixel based representations of image frames are converted to motion representations.", "In addition, the conventional video compression techniques use similarities within image frames, referred to as spatial or intraframe correlation, to provide intraframe compression in which the motion representations within an image frame are further compressed.", "Intraframe compression is based upon conventional processes for compressing still images, such as discrete cosine transform (DCT) encoding.", "[0006] The MPEG standard provides interframe and intraframe compression based upon square blocks or arrays of pixels in video images.", "A video image is divided into macroblocks having dimensions of 16×16 pixels.", "Each macroblock 16×16 is broken into 4 8×8 luminances blocks and 2 or 4 8×8 chrominance blocks.", "For each macroblocks T n in an image frame N, a search is performed across the image of the next successive video frame N+1 or an immediately preceding image frame N−1 (i.e., bidirectionally) to identify the most similar respective macroblocks T N+1 or T N−1 .", "[0007] In an ideal case, the pixels in macroblocks T N and T N+1 are identical, even if the macroblocks have different positions in their respective image frames.", "Under these circumstances, the pixel information in macroblocks T N+1 is redundant to that in macroblocks T N .", "Compression is achieved by substituting the positional translation between macroblocks T N and T N+1 .", "In this simplified example, a single translation vector (Δx, Δy) is designated for the video information associated with the 256 pixels in macroblocks T N+1 .", "[0008] With prior art MPEG compression, or encoding, routines, each macroblocks of pixels, or coefficients, is encoded by a variable length encoding (VLE) unit, and then sent to a compressed output interface as part of an encoded bitstream.", "In constant bitrate (CBR) encoding, the average compressed output, which consists of headers plus VLE unit output, must match a user selected bitrate.", "The encoding system translates the bitrate into target bits per picture and subsequently into target bits per block.", "The bits used by the headers are predictable, but the bits used by the VLE unit output are variable.", "If the VLE unit passes the first N bits of its output per block, where N is the target bits per block, then a constant bitrate can be achieved.", "If the number of bits being used per block is known in advance, the speed of the encoding process can be increased by eliminating the time needed to wait for the actual number of bits to be reported.", "A sophisticated look-ahead bit production scheme is needed to accomplish this.", "SUMMARY OF THE INVENTION [0009] An object of this invention is to encode a digital video picture to an exact size, in terms of number of bits, using an MPEG digital encoder in real-time.", "[0010] Another object of this invention is to provide an encoding method and system that may be used to help maintain an exact bitrate while encoding digital video in real-time.", "[0011] These and other objectives are obtained with a method and system for encoding digital video picture data.", "In accordance with this method, the video picture data is partitioned into a group of blocks, at least some of those blocks are selected, one block at a time, and each of the selected blocks of data is encoded to form encoded coefficients having an associated number of bits.", "The encoded coefficients are outputted, and an accumulated sum of the number of bits in the outputted encoded coefficients is kept.", "The outputting of the encoded coefficients is terminated at a defined time in order to prevent the accumulated sum from exceeding a given number.", "[0012] Preferably, the group of blocks that are partitioned from the video picture data, have a defined order, and the selected blocks are encoded in this defined order.", "Also, with this preferred arrangement, after each time one of the encoded coefficients is outputted, a look-ahead sum is determined by adding (1) the above-mentioned accumulated sum, and (2) the number of bits in the encoded coefficient next in the defined order within the block.", "The outputting of the encoded coefficients is terminated when that look-ahead sum is greater than the given number.", "[0013] Further benefits and advantages of the invention will become apparent from a consideration of the following detailed description, given with reference to the accompanying drawing, which specifies and shows a preferred embodiment of the invention.", "BRIEF DESCRIPTION OF THE DRAWING [0014] The sole FIGURE in the drawing is a block diagram of a digital video picture encoder.", "DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0015] The FIGURE is a block diagram of an MPEG encoder.", "An input video signal contains pixel data for a video frame, and this frame data are stored in the current frame memory 12 .", "This frame data is passed both to a reference frame memory 14 and to a sampling circuit 16 .", "The frame data stored in the reference frame memory 14 is used as reference data in the motion estimation process, discussed below.", "[0016] There are two modes of processing frame data: an intra-coded mode, and a predictive coded mode.", "In the intra-coded mode, each frame is coded using information only from the frame itself;", "and in the predictive coded mode, each frame is coded using motion compensation predicted from a part of a previous coded frame.", "In practice, most of the frames are coded using the predictive-coding mode.", "[0017] Block sampling circuit 16 receives the data stored in the current frame memory 12 and partitions the frame data into spatially non-overlapping blocks of pixel data.", "To provide a reasonable level of adaptiveness, a block size of 8×8 pixels may be used.", "Switch 20 selectively delivers the output blocks of pixel data from the block sampling circuit 16 either to a line 22 for intra-coded processing or to a line 24 for predictive coded processing.", "[0018] For the intra-coded mode, the output of circuit 16 is transmitted to a discrete cosine transform (DCT) circuit 26 .", "Circuit 26 performs a discrete cosine transform, which is a popular mathematical transformation for converting image data to data in the frequency domain.", "The transformed data are then subjected to a quantization process in a quantization circuit 30 using a quantizer matrix and a quantizer step size that is provided by a rate controller 32 .", "The quantized data is then transmitted to a run length coding and variable length coding circuit 34 , which performs run-length and variable length coding of the quantized data.", "The output of the circuit 34 is a coded bit stream ready to be transmitted to a decoder.", "[0019] This bit stream is also passed to the rate controller 32 .", "Based on the number of bits already used at the time of encoding the block, the rate controller 32 adjusts the quantizer step so that the output bit stream satisfies the bit rate requirement of the encoder system.", "The quantized values obtained by circuit 30 are also passed to inverse circuits 36 .", "These circuits reverse both the quantization performed by circuit 30 and the transform performed by circuit 26 to obtain reconstructed data.", "This reconstructed data is stored in memory 40 and may be used for the motion compensation process of the next input frame.", "[0020] For the predictive-coding mode, the output of the block sampling circuit 16 is applied to a motion vector circuit 42 .", "This circuit compares the current frame with a previous frame stored in memory 14 to determine motion vectors.", "This circuit outputs the obtained motion vectors together with the blocks of pixels supplied from sampling circuit 16 .", "[0021] This output is applied to a motion compensation circuit 44 , which may perform motion compensation using the blocks stored in the local frame memory 40 as reference blocks.", "Circuit 44 generates either a differential block (coded with motion compensation) or the original block (coded without motion compensation).", "Circuit 44 also generates a bit indicating whether the block is coded with or without motion compensation.", "This data generated by circuit 44 is applied to DCT circuit 26 and then to circuits 30 and 34 , and this latter circuit outputs the coded bit stream ready for transmission to the decoder.", "[0022] With prior art MPEG encoders, each 8×8 block of coefficients is encoded by the VLE unit 34 and sent to the compressed output interface as part of the encoded bitstream.", "Each encoded coefficient is variable in length.", "The variable-length code is selected based on the value of the given quantized DCT coefficient and its distance from the previous non-zero coefficient in the block as determined by a predefined block scanning order.", "Therefore, the actual encoded size of an 8×8 block, in terms of number of bits, is unknown until after each coefficients's variable-length code has been determined within the VLE unit.", "[0023] In accordance with the present invention, a digital video picture is encoded to an exact size by calculating and setting a bit limit per block in the VLE unit 34 .", "This limit is calculated and set by microcode, schematically represented at 46 .", "This bit limit is used in conjunction with the bitrate control algorithm and the bits per picture target to encode pictures to a predetermined size.", "Also, preferably, this bit limit can be adjusted dynamically by the microcode.", "[0024] More specifically ,as represented by block 50 , the VLE unit 34 accumulates a sum of the total number of bits used per block while receiving the quantized DCT coefficients as input and outputting the variable-length code.", "Also, the VLE unit, as schematically represented by block 52 , compares the accumulated number of used bits with the block limit value set by the microcode, and the VLE terminates its output of variable-length code for a given block when that accumulated number of used bits reaches the limit.", "[0025] The VLE unit then discards the remaining coefficients of the block and finishes its encoding of the block by outputting an end of block (EOB) code.", "This produces a valid (according to the MPEG standard) encoded block with the discarded coefficients being implicitly encoded as coefficients with the value of zero.", "Because of the nature of the DCT transform and quantization used by MPEG encoding, in many, if not most instances, these coefficients would have been zero or a low value even if they were not discarded.", "The coefficients that are discarded from the end of the block are the high frequency coefficients that have the least effect on visual picture quality.", "[0026] Part of the dynamics of this overall mechanism stems from the fact that the encoder uses variable-length codes and does not always reach the limit exactly.", "Preferably, any variable-length code produced is included in the encoded bitstream in its entirety.", "In order to accomplish this, the VLE unit 34 looks ahead one coefficient to determine if the next coefficient's variable-length code will cause the accumulated block sum to exceed the block limit.", "If it will exceed that limit, the VLE unit terminates the block as described above.", "If it will not exceed the limit, the VLE unit outputs the variable-length code and looks to the next coefficient and so on.", "In this way, the block limit is never exceeded, but many times it is not reached.", "When it is not reached exactly, the microcode recognizes this from the bit count that the VLE unit reports, and adjusts the block limit for the next block accordingly in order to use up the allocated bits per picture.", "By the time the last block of a picture is encoded, the predetermined picture size will be met.", "[0027] In the preferred implementation, the microcode 46 sets the VLE block limits on a per macroblock basis.", "The microcode sets two limit values.", "One limit is used for luminance blocks, and the other is used for chrominance blocks.", "This allows for the capability of using more bits for the luminance blocks and less for the chrominance blocks or vice versa.", "With alternative implementations, a different limit may be set for each block of a macroblock, or a new block limit may be provided for each block after adjusting for unused bits.", "[0028] The present invention is an alternative to a quantization constraining mechanism, described in the prior art, that predetermines that a set number of coefficients will be “zeroed”", "out.", "This mechanism can not be used effectively to meet exact picture sizes because it is used prior to the VLE unit in the encoding process.", "Since it is used prior to the VLE unit, it can not know the final output size, which is determined by the variable-length codes.", "In addition, it may be blanketing out coefficients that are not necessary (i.e., the encoded blocks may be small even without the constraining, making the constraining unnecessary and most likely detrimental to picture quality).", "[0029] With the block limit solution used in the present invention, the remainder of the block is only zeroed out if the encoded size of the block has reached the limit.", "Therefore, blocks with encoded sizes smaller than the limit will be encoded and included in the encoded bitstream in their entirety.", "Picture quality is not compromised to the unacceptable extent of the prior art quantization constraining mechanism.", "[0030] The method and system disclosed herein is useful in many digital video encoding applications.", "Because its intent is to encode a picture to an exact size, it is an important function for the application of video splicing and editing.", "It is also used in normal real-time encoding in conjunction with the encoder's bitrate algorithm to meet picture targets that are calculated.", "[0031] While the invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention." ]
[0001] This application claims the benefit of U.S. Provisional application No. 60/173,133, filed Dec. 27, 1999, entitled “Solid Oxide Electrolyte, Fuel Cell Module, and Method”, by Helfinstine et al. BACKGROUND OF THE INVENTION [0002] The present invention is in the field of electrochemical devices and more particularly relates to flexible ceramic sheets for solid electrolytes and electrolyte/electrode assemblies for devices such as fuel cells. [0003] U.S. Pat. No. 5,089,455 describes strong, thin, flexible ceramic sheets and tapes of various compositions, and methods for making them. As taught in U.S. Pat. No. 5,273,837, such sheets can be used to provide solid oxide electrolytes and other components for fuel cells that exhibit improved resistance to thermal shock damage due in part to the flexibility and high strength of the ceramic sheets. Further, U.S. Pat. No. 5,519,191 describes the incorporation of thin ceramic sheets into fluid heating structures of corrugated shape that include thin conductive metal layers as electrical heating elements. [0004] Curved electrode and electrolyte designs that reduce the thermal stresses arising during the normal operation of fuel cells are disclosed in published PCT patent application W099/44254. The use of corrugated planar electrode/electrolyte sheets to control such stresses is proposed by K. Tomida et al. in “Preparation of Solid Electrolyte Thin Films for Relaxing Thermal Stresses”, Proceedings of the Third International Symposium on Solid Oxide Fuel Cells, Proceedings Volume 93-4, pages 74-81, Singhal and Iwahara, Editors, The Electrochemical Society, Inc. ( 1993 ). [0005] Substantially planar electrolyte sheets supporting cathodic and anodic electrode layers have been proposed for use in a number of different fuel cell configurations, including configurations that may be characterized as stacked fuel cell designs. In one such stacked design, each planar electrode/electrolyte sub-unit is bonded to and edge-supported by a framing manifold structure, with multiple frames and sub-units being stacked and electrically interconnected in parallel or series to provide the fuel cell output current or voltage required for the particular application of interest. [0006] In this and similar manifolded fuel cell arrangements, even perfect thermal expansion matching of the electrolyte/electrode sheets to the supporting manifold structure does not avoid thermal cycling stress. This is because the manifold structures typically have much higher thermal mass than the sheets, and heat and cool sufficiently more slowly than the electrolyte/electrode sheets that the electrolyte/electrode sheets can be put into severe tension in many sheet directions at once regardless of the extent to which thermal expansion matching is employed. [0007] Unfortunately, the known materials and designs for thin ceramic fuel cell electrolytes do not provide the level of thermal durability necessary to insure dependable fuel cell operation in stacked and other configurations during the extended temperature cycling that cannot be avoided in normal service. In particular, prior art electrolytes do not provide the requisite combination of high multiaxial strain tolerance and high resistance to damage under large strains that will be needed to secure dependable long-term service in fuel cells. SUMMARY OF THE INVENTION [0008] The present invention provides highly strain tolerant ceramic electrolyte layers wherein the electrolyte is formed of a strong, thin ceramic sheet incorporating a two-dimensional surface indentation pattern. For example, flexible ceramic sheet having a surface indentation pattern providing a strain tolerance of not less than 0.5% in any direction in the sheet plane, more preferably a strain tolerance of at least 1% in any direction in the sheet plane, can readily be provided by means hereinafter described. [0009] Useful indentation patterns are those that impart a very high multi-axial strain tolerance to the sheet, within the plane of the sheet, without introducing stress concentrators that reduce sheet strength. Examples of suitable indentation patterns are those comprising multidirectional corrugations or waves, protrusions or indentations of circular, polygonal, or other cross-section, and other contiguous or overlapping indentations or protrusions that do not introduce sharp sheet curvature and do not alter the generally planar configuration of the sheet. One-dimensional patterns, such as single-direction corrugations that provide only uni-axial strain tolerance, are not useful. [0010] The preferred indentation patterns allow not only large in-plane effective strains but also large elastic deformations normal to the plane of the sheet. This permits the sheets to withstand large thermal gradients and large thermal expansion differentials from associated other fuel cell components without risking electrolyte fracture and loss of effective current generation. [0011] The invention further includes a process for making thin, strain-tolerant ceramic sheet for electrolyte and electrolyte/electrode fabrication. In general the process involves the steps of forming a thin cohesive green sheet layer on a suitable fugitive support, forming patterned indentations in the sheet while in the green state, and then consolidating the sheet with its impressed indentation pattern by sintering to remove binders and any fugitive supports. Methods that can be used to impress the desired indentation pattern in the green sheet include vacuum forming, pressing, roll pressing, embossing, or other conventional surface shaping procedures. [0012] Strain tolerant electrolyte sheets produced as described can be employed in a variety of different fuel cell configurations, but are of particular value in planar stacked fuel cell designs. This is because the strain-tolerant electrolyte sheets of the invention offer much higher resistance to mechanical failure under temperature cycling conditions, particularly in an edge-supported electrolyte configuration, than do conventional corrugated or other electrolyte sheet designs. DESCRIPTION OF THE DRAWINGS [0013] The invention may be further understood by reference to the drawings, wherein: [0014] [0014]FIG. 1 illustrates an electrolyte sheet incorporating a full-surface hexagonal indentation pattern in accordance with the invention; [0015] [0015]FIG. 2 illustrates an electrolyte sheet incorporating a peripheral surface portion incorporating an indentation pattern in accordance with the invention; [0016] [0016]FIG. 3 illustrates forming apparatus useful for the production of electrolyte sheet such as shown in FIG. 1; [0017] [0017]FIGS. 4 a - 4 c illustrate examples of multi-directional corrugation patterns outside the scope of the invention; and [0018] [0018]FIGS. 5 a - 5 f illustrate examples of multi-directional corrugation patterns imparting high effective strain tolerance to flexible ceramic sheets provided in accordance with the invention. DETAILED DESCRIPTION [0019] Anode- and cathode-supported solid oxide fuel cells with thin electrolyte layers are of immediate commercial interest because of the impressive single cell power “densities” that have recently been reported. Some single cell power densities above 1 watt/cm 2 have been measured under ideal laboratory conditions. The electrolyte in these single cells has a thickness below about 50 microns, approaching 10 microns or thinner. Co-calendering, laminated cast tapes, colloidal coating on partially sintered electrodes and other methods such as co-tape casting and even ECVD and other vapor/powder deposition methods can be used to make such single cells. [0020] The supporting electrode in these cell configurations is relatively thick, e.g., from 300 microns to 2,000 microns in thickness. The objective of combining a thin electrolyte with a relatively thick electrode, usually the anode, is to provide mechanical support for the thin electrolyte. Corrugations of the type we disclose here will not result in a major improvement in strain tolerance in cells incorporating electrodes of this thickness. [0021] Electrode-supported fuel cells have been reported wherein the electrode surface has been textured to give higher surface area along the plane of the electrolyte, in order to increase the apparent power density. However, without a matching texture across the entire tri-layer anode/electrolyte/cathode composite structure, there will be minimal improved strain tolerance. And, if the electrode is too thick or has a high elastic modulus or has low fracture strength, improved strain tolerance will be minimal. [0022] For performance and also for material usage (cost) reasons, anode- and cathode-supported thin electrolyte SOFC cell designs will not benefit greatly from the thin electrolyte and electrode approaches of the invention unless electrode/electrolyte/electrode tri-layers below about 150 microns in total thickness, perhaps approaching 50 microns in total thickness are, to be employed. However, within these thickness ranges electrode-supported tri-layers will clearly benefit from corrugation of the entire tri-layer structure, particularly if at the same time attention is given to eliminating large strength reducing flaws, layering the cells with surfaces in compression, or other material strengthening/toughening measures. [0023] Lowering the elastic modulus of the outside surface layers of the cell will also help to improve structural strain tolerance. If the anode is graded such that there is primarily nickel metal on the exterior of the electrode, some ductility in that exterior surface will be present. Ductility of the metal electrode exterior can be used in conjunction with corrugation and a thin electrolyte/electrode structure to further enhance strain tolerance, providing a measure of strain tolerance not previously obtainable in electrode-supported cells. [0024] In all solid oxide fuel cells, maintaining good electrical contact between the interconnects and the electrodes is necessary for good performance. Contact problems often arise in stacked planar fuel cell assemblies, especially those incorporating relatively dense electrolyte/electrode/manifold structures, as the result of temperature gradients along the gas flow directions within the device that cause differential thermal strains to warp and twist the structure. [0025] One advantage of the use of flexible electrolyte/electrode sheets in frame-supported designs is the ability to shape the edges of the sheets to improve edge sealing and reduce loss of contact problems. Advantageously, where electrolyte/electrode sheets with large effective multi-axial strain tolerances are used, not only is the risk of mechanical failure and/or loss of electrical contact in the edge seals reduced, but also sheet resilience in directions normal to the sheet plane is improved, significantly lowering the likelihood of sheet fracture and/or loss of electrical contact through structural warpage. [0026] The particular sheet indentation or multi-directional corrugation pattern used to impart high multi-directional effective strain tolerance to the sheet may be chosen according to the particular needs of the environment within which the fuel cell elements are intended to operate. Among the patterns that that give the largest and most uniform effective strain tolerance in multiple directions are patterns such as such as hexagons and Penrose tiles (quasi—periodic structures), “T” shapes, woven squares, bow ties, wiggly squares, flex rectangles (herringbone patterns), and certain combinations of squares and octagons. [0027] Patterns that are not useful to build the required multidirectional strain tolerance are those that have straight corrugation ridges, or straight paths or areas of completely flat sheet, running in straight uninterrupted lines from one edge of the sheet to another. Uninterrupted ridge or flat lines in the sheet surface define axes of very low strain tolerance in the sheet plane, greatly increasing the risk of sheet or contact failure in the event that significant stresses along such axes arise in the course of use. Patterns of this type include parallel corrugation patterns, and also many regular indentation patterns based on repeating triangles, squares and rectangles if the indentations are not appropriatedly staggered to avoid linear ridges or flats. [0028] [0028]FIGS. 4 a - 4 c of the drawing illustrate multidirectional corrugation patterns that are not useful to provide strain-tolerant electrolyte sheets in accordance with the invention. In those figures, the lines represent the outlines or borders of sheet indentations or protrusions having the shapes enclosed by the lines. A shared characteristic of all of these designs is that substantially all of the lines correspond to flat straight paths spanning the entire widths or lengths of the sheets. Accordingly the corrugation patterns shown, although multi-directional in nature, impart essentially no enhanced strain tolerance to the sheets in directions parallel to those span lines. [0029] [0029]FIGS. 5 a - 5 f of the drawing, on the other hand, illustrate multidirectional corrugation patterns that increase the strain tolerance of the sheet in every direction in the sheet plane. The indentation patterns represented by these line drawings are characterized by the complete absence of span lines corresponding to straight ridge or flat lines crossing the entire lengths or widths of the sheets. [0030] Concentric corrugations are appropriate for circular or near circular electrolyte sheet but are not as useful for rectangles and square sheets. Radial corrugations that have straight ridge lines running from one edge of a square or rectangular sheet to the opposite edge of the sheet are not useful. Concentric corrugations can have curved ridge lines from one edge of a square or rectangular sheet to the adjacent edge of the sheet. Of course, completely a-periodic patterns, if free of straight ridge or flat lines, could also be used. [0031] While increasing the depth of the selected indentation patterns theoretically increases the effective strain tolerance attainable in the sheets, overly deep indentations involving a high rate or sharpness of change in plane are generally avoided for a number of reasons. First, shallow corrugations are more compatible with conventional electrode deposition methods such as screen printing, and additionally preserve a substantially planar electrode/electrolyte shape that simplifies the design of associated fuel cell elements such as electrical contacts and current collectors. Secondly, deeper indentations can give rise to abrupt sheet curvatures that act as stress concentrators at higher sheet elongations. Thus the theoretical strain increases of deep indentation designs can be more than offset by reductions in sheet failure stress arising from stress concentrations developed in the sheets when under high strain. [0032] Impressing the selected indentation patterns on thin ceramic sheet can be accomplished in a number of different ways. For example, sufficiently thin ceramic sheet materials can be reformed through a process of superplastic deformation at high temperatures below their melting temperatures. [0033] However, more effective and economic sheet patterning can be achieved according to the invention through the process of reshaping unfired green sheet at or near room temperature prior to sintering to an integral ceramic film. Binder formulations useful for the tape-casting of powdered ceramics are known that offer sufficient plasticity and elongation to permit easy room-temperature pressing of many of the useful indentation patterns. Alternatively, green ceramic sheet formed by tape casting powder dispersions or suspensions together with thin thermoplastic base films can be processed by any of the various embossing or vacuum reforming methods useful for surface patterning plastics, with the base film providing any needed additional support for the green ceramic sheet throughout the reforming process. [0034] The following illustrative Example describes one low-temperature reforming method that may be used. EXAMPLE Production of Strain-Tolerant Ceramic Sheet [0035] A green polymer-bonded ceramic powder sheet is made from a zirconia powder as follows. A ceramic slip is first prepared by combining a yttria-stabilized zirconia powder (TZ-3Y powder from the Tosoh Corporation, Japan) with a vehicle consisting of a mixture of ethanol, butanol, propylene glycol and water. 100 g of the zirconia powder free of contaminants is added to a previously prepared mixture of 36.4 g of ethanol, 8.8 g of 1-butanol, 2 g of propylene glycol, 2.5 g of distilled water, and 1 g of a liquid dispersant (Emphos PS-21A dispersant from the Witco Chemical Company). The resulting powder dispersion is transferred to a milling bottle and is vibration-milled for 72 hours using zirconia balls as the milling media. [0036] To remove coarse zirconia particles from the suspension and narrow the particle size distribution in the final slip, the milled suspension is processed through a double settling process wherein it is first allowed to settle for 72 hours and the liquid then separated from the sediment by decantation. The resulting slip is then allowed to settle for another 24 hours and separated from the sediment for final processing. [0037] The slip thus provided is next flocculated through the addition of an alcohol-acetic acid mixture consisting of 50% of glacial acetic acid and 50% of isopropyl alcohol by weight. This mixture is added to the slip in a proportion sufficient to provide 1 part of acetic acid for each 100 parts by weight of ceramic powder remaining after settling, and the acidified slip is then shaken to assure complete mixing. After the addition of the flocculant, film-forming additives consisting of about 3.5 parts by weight of a dibutyl pthalate liquid plasticizer and 6 parts by weight of a polyvinyl butyral powder binder are added to the slip for each 100 parts by weight of zirconia powder remaining after settling, with gentle shaking after each addition to achieve thorough mixing. The resulting slip has a viscosity suitable for tape casting. [0038] A flexible cohesive zirconia sheet is formed from this slip by casting it onto a thin methyl cellulose release layer previously applied to a flat casting surface. The release layer consists of a dried tape-cast methyl cellulose coating of about 0.0005 inch thickness formed from a 2% (wt.) aqueous solution of Dow K-75 Methocel® cellulose. The tape-cast layer thus provided provides a flexible green ceramic sheet layer after the removal of volatile slip vehicle components by drying. [0039] After this flexible ceramic sheet layer has been formed, a supporting acrylic polymer overlayer is tapecast over the ceramic sheet and dried. This overlayer is provided from an acrylate solution containing 71% of ethyl acetate solvent to which 25% of polymethylmethacrylate powder and 3.5% of dibutyl pthalate (Aldrich Chemical Company) have been added. The acrylate solution is tapecast and then dried to provide a flexible polymer film overcoating. This layer adheres well to the underlying ceramic sheet layer, providing a cohesive composite sheet consisting of the ceramic sheet and acrylate overcoating. This cohesive composite sheet is easily separated from the cellulose release layer after all layers have been completely dried. [0040] To shape a strain-tolerant zirconia sheet from the composite green ceramic sheet thus provided, a metal form with regularly spaced hexagonal cutouts is provided. This form consists of a metal grid about 0.6 mm in thickness incorporating hexagonal cutouts in a close-packed array made up of offset rows of hexagons forming a honeycomb pattern, with a row-to-row center spacing of 6.5 mm. The residual metal framework surrounding the cutouts provides separating ribs about 0.6 mm in width and 0.6 mm in height between each hexagon and its six neighboring hexagons. FIGS. 2 - 2 a of the drawing illustrate a metal form of this design, wherein a plurality of hexagonal cutouts 12 are arranged in close-packed array within form 10 . [0041] To form multi-directional corrugated zirconia sheet the metal form thus provided is placed on a vacuum table and the table and form are preheated to about 60° C. A section of the composite green ceramic sheet about 31 cm by 24 cm in size made as above described is then placed over the form and an insulating section of polymer foam board is placed over the sheet and form to allow them to reach uniform temperature. The vacuum table is then activated for about ten seconds, following which the vacuum is released and the green ceramic sheet is removed from the form and inspected. [0042] The multi-directionally corrugated sheet resulting from this reforming step is a regularly indented green ceramic sheet incorporating hexagonal indentations separated from each other by spacings corresponding to the spacings between adjacent hexagonal cutouts in the metal honeycomb form. This green sheet is trimmed to even rectangular shape with a rotary cloth cutter and then sintered in air on a refractory setter in an electric kiln operating at 1430° C. for a period of two hours. The fully sintered sheet is then removed from the kiln and examined. [0043] FIGS. 1 - 1 ( a ) of the drawing present a schematic top plan and a front elevational cross-sectional view, respectively, of a ceramic sheet 20 which has been fully sintered to set a hexagonal indentation pattern incorporating a plurality of hexagonal indentations 22 established during reforming of the green sheet substantially as above described. When made in accordance with this procedure the sintered sheet will be of zirconia-3 mole % yttria composition with a thickness of about 20 um, supporting an array of hexagonal indentations about 0.15 mm in depth with a row-to-row center spacing of about 4.5 mm between the rows of the hexagons. The unusually high multidirectional strain tolerance of this sheet is manifested by an easily discerned stretch or “give” in the sheet when manually stressed in the sheet plane. The strain tolerance of the free-standing sheet is measured to be in excess of 1% without cracking. [0044] Variations in the reforming procedure employed to process green ceramic sheets can be used to change the nature or extent of the indentation patterns developed. For example, using shorter vacuum forming times, e.g., of 1 to 3 or 4 seconds in duration, give shallower corrugations, while using a polyethylene sheet on top of the green ceramic sheet to increase vacuum retention, or using longer forming times, give deeper (higher) corrugations. [0045] As previously noted, however, attempting to address the problems of thermal stress through the use of widely spaced corrugations of excessive height or curvature, instead of shallow, closely spaced corrugations, limits strain tolerance and ultimate failure strength of the ceramic sheet. An illustrative example of this effect is provided by the hypothetical case of a bi-directionally corrugated yttria-stabilized zirconia (YSZ) sheet of about 40 micrometers thickness featuring a criss-crossing array of relatively large but abrupt corrugations or ridges. The corrugations would be offset 90 degrees from each other at a ridge spacing of approximately 1 cm, a ridge height of about 2 mm, and a ridge base width of about 1 mm, with a radius of curvature for the ridge edges of 0.4 mm. [0046] While the two-dimensional corrugations in this sheet would improve sheet strain tolerance in multiple directions in the sheet plane, free-standing ceramic sheet of this type will suffer crack damage at strains well below useful levels. Such cracking failures will most often occur at corrugation peak locations, due to the depth and spacing of the corrugations employed and the concentration of bending stresses at corrugation ridges. [0047] For the foregoing reasons, indentation patterns provided in accordance with the invention will have indentation populations along any axis in the plane of the sheet at least adequate to permit theoretical sheet elongations of 1% or greater in all directions within the plane of the sheet. Desirably, for sintered zirconia-based ceramic sheets, the corrugation or other indentation patterns will not incorporate curvature radii below about 2 mm or 100× the thickness of the sheet. Further, the corrugations or other indentations will preferably not exceed about 2 mm in height as measured from the base plane of the sheet. [0048] A particular advantage of the invention is that alternative indentation patterns adapted to specific applications for strain-tolerant ceramic sheets may be developed to meet particular needs. For example, where high flatness in selected sheet portions is required to meet special electrical contact or electrode processing requirements, sheets incorporating flat sections together with sections incorporating patterned indentations can be provided. [0049] [0049]FIG. 3 of the drawing illustrates one sheet design of this type, incorporating a multi-directionally corrugated or indented border portion 30 incorporating hexagonal indentations 32 surrounding a rectangular flat central section 34 . This design is particularly well adapted for applications wherein the sheet is to be edge-mounted in a surrounding frame. For a mounting of this type the flat central section of the sheet is isolated from undue stress in all directions in the sheet plane by the surrounding, highly strain tolerant indented border section. Further, the strain-tolerant edge portions facilitate edge mounting since gas-tight edge seals requiring larger sheet deformations can be accommodated with a lower risk of sheet failure. [0050] The importance of high multi-directional strain tolerance in ceramic sheets intended for use as fuel cell electrolytes can be better appreciated from a consideration of the damaging effects of thermal stress on the components of fuel cells, especially fuel cells that are subjected to frequent thermal cycling. One fuel cell design to be considered incorporates a yttria-stabilized zirconia electrolyte sheet mounted in a relatively massive surrounding frame that functions as a sheet separator and enclosure for fuel or oxidant gases to be supplied to the sheet. Such frames will be of much higher thermal mass than the electrolyte sheet and its supported electrode layers. [0051] In some designs the electrolyte/electrode sheets will be mounted in these frames so that they will be substantially unstressed at fuel cell operating temperatures. If a fuel cell operating temperature of 800 C. is specified and the cell is turned off, the electrode/electrolyte sheet will cool to ambient temperatures much more rapidly than the frame. In fact, it can be determined from the known thermal expansion coefficient of yttria-stabilized zirconia (110×10 −7 /° C.) that a strain as high as 0.9% can be developed in an electrolyte/electrode sheet mounted in such a frame at the point of maximum sheet/frame temperature differential during the cooling process. This strain can readily be accommodated by the strain-tolerant electrolyte sheets of the invention. [0052] Other corrugation or indentation designs that are free of straight ridge or flat lines and thus provide high strain tolerance in accordance with the invention are illustrated by line representations in FIGS. 5 b - 5 f of the drawing. In each of these drawings the lines indicate the outlines of the selected indentations, and straight lines traversing the entire indentation pattern are entirely absent. [0053] The imprinting of green ceramic sheets with any of these various indentation patterns can readily be carried out in a continuous process, and can be accomplished at any one of a number of different points in the sheet forming process ranging from the time the green ceramic sheet is first cast to the point at which the dried green sheet is ready for sintering. Further, any of the various indentation patterns having the required shape and frequency characteristics may be used in combination with sheet configurations other than strictly planar configurations, including tubular or dome configurations, to increase multi-axial strain tolerance in tubular or other non-planar fuel cell designs. [0054] For some applications, anisotropic corrugation patterns may be useful to impart anisotropic strain tolerance and stiffness to the sheet. Depending upon the particular thermal and mechanical environment in which the ceramic sheet is to be used, higher strain tolerance in one direction than another may be required. One example of such an environment would be a fuel cell design wherein steeper thermal gradients are expected along one axis than along other axes, due to irregular gas flow patterns across the electrolyte. The use of different indentation patterns at different locations on a single sheet may also be useful to compensate for uneven temperature distributions within the cell. These and numerous other modifications of the products, materials, processes and apparatus hereinabove described will be resorted to by those skilled in the art within the scope of the appended claims.
Flexible ceramic sheets with enhanced strain tolerance for electrochemical applications such as solid oxide fuel cell electrolytes incorporate a surface indentation pattern providing a strain tolerance of not less than 0.5% in any direction in the sheet plane, being made from flexible green ceramic sheet comprising a ceramic powder and a thermoplastic organic binder by heating and reshaping the green sheet to form a multidirectional surface corrugation pattern therein, followed by firing to sinter the ceramic powder to a flexible ceramic sheet having a multi-directional surface corrugation pattern.
Summarize the key points of the given document.
[ "[0001] This application claims the benefit of U.S. Provisional application No. 60/173,133, filed Dec. 27, 1999, entitled “Solid Oxide Electrolyte, Fuel Cell Module, and Method”, by Helfinstine et al.", "BACKGROUND OF THE INVENTION [0002] The present invention is in the field of electrochemical devices and more particularly relates to flexible ceramic sheets for solid electrolytes and electrolyte/electrode assemblies for devices such as fuel cells.", "[0003] U.S. Pat. No. 5,089,455 describes strong, thin, flexible ceramic sheets and tapes of various compositions, and methods for making them.", "As taught in U.S. Pat. No. 5,273,837, such sheets can be used to provide solid oxide electrolytes and other components for fuel cells that exhibit improved resistance to thermal shock damage due in part to the flexibility and high strength of the ceramic sheets.", "Further, U.S. Pat. No. 5,519,191 describes the incorporation of thin ceramic sheets into fluid heating structures of corrugated shape that include thin conductive metal layers as electrical heating elements.", "[0004] Curved electrode and electrolyte designs that reduce the thermal stresses arising during the normal operation of fuel cells are disclosed in published PCT patent application W099/44254.", "The use of corrugated planar electrode/electrolyte sheets to control such stresses is proposed by K. Tomida et al.", "in “Preparation of Solid Electrolyte Thin Films for Relaxing Thermal Stresses”, Proceedings of the Third International Symposium on Solid Oxide Fuel Cells, Proceedings Volume 93-4, pages 74-81, Singhal and Iwahara, Editors, The Electrochemical Society, Inc. ( 1993 ).", "[0005] Substantially planar electrolyte sheets supporting cathodic and anodic electrode layers have been proposed for use in a number of different fuel cell configurations, including configurations that may be characterized as stacked fuel cell designs.", "In one such stacked design, each planar electrode/electrolyte sub-unit is bonded to and edge-supported by a framing manifold structure, with multiple frames and sub-units being stacked and electrically interconnected in parallel or series to provide the fuel cell output current or voltage required for the particular application of interest.", "[0006] In this and similar manifolded fuel cell arrangements, even perfect thermal expansion matching of the electrolyte/electrode sheets to the supporting manifold structure does not avoid thermal cycling stress.", "This is because the manifold structures typically have much higher thermal mass than the sheets, and heat and cool sufficiently more slowly than the electrolyte/electrode sheets that the electrolyte/electrode sheets can be put into severe tension in many sheet directions at once regardless of the extent to which thermal expansion matching is employed.", "[0007] Unfortunately, the known materials and designs for thin ceramic fuel cell electrolytes do not provide the level of thermal durability necessary to insure dependable fuel cell operation in stacked and other configurations during the extended temperature cycling that cannot be avoided in normal service.", "In particular, prior art electrolytes do not provide the requisite combination of high multiaxial strain tolerance and high resistance to damage under large strains that will be needed to secure dependable long-term service in fuel cells.", "SUMMARY OF THE INVENTION [0008] The present invention provides highly strain tolerant ceramic electrolyte layers wherein the electrolyte is formed of a strong, thin ceramic sheet incorporating a two-dimensional surface indentation pattern.", "For example, flexible ceramic sheet having a surface indentation pattern providing a strain tolerance of not less than 0.5% in any direction in the sheet plane, more preferably a strain tolerance of at least 1% in any direction in the sheet plane, can readily be provided by means hereinafter described.", "[0009] Useful indentation patterns are those that impart a very high multi-axial strain tolerance to the sheet, within the plane of the sheet, without introducing stress concentrators that reduce sheet strength.", "Examples of suitable indentation patterns are those comprising multidirectional corrugations or waves, protrusions or indentations of circular, polygonal, or other cross-section, and other contiguous or overlapping indentations or protrusions that do not introduce sharp sheet curvature and do not alter the generally planar configuration of the sheet.", "One-dimensional patterns, such as single-direction corrugations that provide only uni-axial strain tolerance, are not useful.", "[0010] The preferred indentation patterns allow not only large in-plane effective strains but also large elastic deformations normal to the plane of the sheet.", "This permits the sheets to withstand large thermal gradients and large thermal expansion differentials from associated other fuel cell components without risking electrolyte fracture and loss of effective current generation.", "[0011] The invention further includes a process for making thin, strain-tolerant ceramic sheet for electrolyte and electrolyte/electrode fabrication.", "In general the process involves the steps of forming a thin cohesive green sheet layer on a suitable fugitive support, forming patterned indentations in the sheet while in the green state, and then consolidating the sheet with its impressed indentation pattern by sintering to remove binders and any fugitive supports.", "Methods that can be used to impress the desired indentation pattern in the green sheet include vacuum forming, pressing, roll pressing, embossing, or other conventional surface shaping procedures.", "[0012] Strain tolerant electrolyte sheets produced as described can be employed in a variety of different fuel cell configurations, but are of particular value in planar stacked fuel cell designs.", "This is because the strain-tolerant electrolyte sheets of the invention offer much higher resistance to mechanical failure under temperature cycling conditions, particularly in an edge-supported electrolyte configuration, than do conventional corrugated or other electrolyte sheet designs.", "DESCRIPTION OF THE DRAWINGS [0013] The invention may be further understood by reference to the drawings, wherein: [0014] [0014 ]FIG. 1 illustrates an electrolyte sheet incorporating a full-surface hexagonal indentation pattern in accordance with the invention;", "[0015] [0015 ]FIG. 2 illustrates an electrolyte sheet incorporating a peripheral surface portion incorporating an indentation pattern in accordance with the invention;", "[0016] [0016 ]FIG. 3 illustrates forming apparatus useful for the production of electrolyte sheet such as shown in FIG. 1;", "[0017] [0017 ]FIGS. 4 a - 4 c illustrate examples of multi-directional corrugation patterns outside the scope of the invention;", "and [0018] [0018 ]FIGS. 5 a - 5 f illustrate examples of multi-directional corrugation patterns imparting high effective strain tolerance to flexible ceramic sheets provided in accordance with the invention.", "DETAILED DESCRIPTION [0019] Anode- and cathode-supported solid oxide fuel cells with thin electrolyte layers are of immediate commercial interest because of the impressive single cell power “densities”", "that have recently been reported.", "Some single cell power densities above 1 watt/cm 2 have been measured under ideal laboratory conditions.", "The electrolyte in these single cells has a thickness below about 50 microns, approaching 10 microns or thinner.", "Co-calendering, laminated cast tapes, colloidal coating on partially sintered electrodes and other methods such as co-tape casting and even ECVD and other vapor/powder deposition methods can be used to make such single cells.", "[0020] The supporting electrode in these cell configurations is relatively thick, e.g., from 300 microns to 2,000 microns in thickness.", "The objective of combining a thin electrolyte with a relatively thick electrode, usually the anode, is to provide mechanical support for the thin electrolyte.", "Corrugations of the type we disclose here will not result in a major improvement in strain tolerance in cells incorporating electrodes of this thickness.", "[0021] Electrode-supported fuel cells have been reported wherein the electrode surface has been textured to give higher surface area along the plane of the electrolyte, in order to increase the apparent power density.", "However, without a matching texture across the entire tri-layer anode/electrolyte/cathode composite structure, there will be minimal improved strain tolerance.", "And, if the electrode is too thick or has a high elastic modulus or has low fracture strength, improved strain tolerance will be minimal.", "[0022] For performance and also for material usage (cost) reasons, anode- and cathode-supported thin electrolyte SOFC cell designs will not benefit greatly from the thin electrolyte and electrode approaches of the invention unless electrode/electrolyte/electrode tri-layers below about 150 microns in total thickness, perhaps approaching 50 microns in total thickness are, to be employed.", "However, within these thickness ranges electrode-supported tri-layers will clearly benefit from corrugation of the entire tri-layer structure, particularly if at the same time attention is given to eliminating large strength reducing flaws, layering the cells with surfaces in compression, or other material strengthening/toughening measures.", "[0023] Lowering the elastic modulus of the outside surface layers of the cell will also help to improve structural strain tolerance.", "If the anode is graded such that there is primarily nickel metal on the exterior of the electrode, some ductility in that exterior surface will be present.", "Ductility of the metal electrode exterior can be used in conjunction with corrugation and a thin electrolyte/electrode structure to further enhance strain tolerance, providing a measure of strain tolerance not previously obtainable in electrode-supported cells.", "[0024] In all solid oxide fuel cells, maintaining good electrical contact between the interconnects and the electrodes is necessary for good performance.", "Contact problems often arise in stacked planar fuel cell assemblies, especially those incorporating relatively dense electrolyte/electrode/manifold structures, as the result of temperature gradients along the gas flow directions within the device that cause differential thermal strains to warp and twist the structure.", "[0025] One advantage of the use of flexible electrolyte/electrode sheets in frame-supported designs is the ability to shape the edges of the sheets to improve edge sealing and reduce loss of contact problems.", "Advantageously, where electrolyte/electrode sheets with large effective multi-axial strain tolerances are used, not only is the risk of mechanical failure and/or loss of electrical contact in the edge seals reduced, but also sheet resilience in directions normal to the sheet plane is improved, significantly lowering the likelihood of sheet fracture and/or loss of electrical contact through structural warpage.", "[0026] The particular sheet indentation or multi-directional corrugation pattern used to impart high multi-directional effective strain tolerance to the sheet may be chosen according to the particular needs of the environment within which the fuel cell elements are intended to operate.", "Among the patterns that that give the largest and most uniform effective strain tolerance in multiple directions are patterns such as such as hexagons and Penrose tiles (quasi—periodic structures), “T”", "shapes, woven squares, bow ties, wiggly squares, flex rectangles (herringbone patterns), and certain combinations of squares and octagons.", "[0027] Patterns that are not useful to build the required multidirectional strain tolerance are those that have straight corrugation ridges, or straight paths or areas of completely flat sheet, running in straight uninterrupted lines from one edge of the sheet to another.", "Uninterrupted ridge or flat lines in the sheet surface define axes of very low strain tolerance in the sheet plane, greatly increasing the risk of sheet or contact failure in the event that significant stresses along such axes arise in the course of use.", "Patterns of this type include parallel corrugation patterns, and also many regular indentation patterns based on repeating triangles, squares and rectangles if the indentations are not appropriatedly staggered to avoid linear ridges or flats.", "[0028] [0028 ]FIGS. 4 a - 4 c of the drawing illustrate multidirectional corrugation patterns that are not useful to provide strain-tolerant electrolyte sheets in accordance with the invention.", "In those figures, the lines represent the outlines or borders of sheet indentations or protrusions having the shapes enclosed by the lines.", "A shared characteristic of all of these designs is that substantially all of the lines correspond to flat straight paths spanning the entire widths or lengths of the sheets.", "Accordingly the corrugation patterns shown, although multi-directional in nature, impart essentially no enhanced strain tolerance to the sheets in directions parallel to those span lines.", "[0029] [0029 ]FIGS. 5 a - 5 f of the drawing, on the other hand, illustrate multidirectional corrugation patterns that increase the strain tolerance of the sheet in every direction in the sheet plane.", "The indentation patterns represented by these line drawings are characterized by the complete absence of span lines corresponding to straight ridge or flat lines crossing the entire lengths or widths of the sheets.", "[0030] Concentric corrugations are appropriate for circular or near circular electrolyte sheet but are not as useful for rectangles and square sheets.", "Radial corrugations that have straight ridge lines running from one edge of a square or rectangular sheet to the opposite edge of the sheet are not useful.", "Concentric corrugations can have curved ridge lines from one edge of a square or rectangular sheet to the adjacent edge of the sheet.", "Of course, completely a-periodic patterns, if free of straight ridge or flat lines, could also be used.", "[0031] While increasing the depth of the selected indentation patterns theoretically increases the effective strain tolerance attainable in the sheets, overly deep indentations involving a high rate or sharpness of change in plane are generally avoided for a number of reasons.", "First, shallow corrugations are more compatible with conventional electrode deposition methods such as screen printing, and additionally preserve a substantially planar electrode/electrolyte shape that simplifies the design of associated fuel cell elements such as electrical contacts and current collectors.", "Secondly, deeper indentations can give rise to abrupt sheet curvatures that act as stress concentrators at higher sheet elongations.", "Thus the theoretical strain increases of deep indentation designs can be more than offset by reductions in sheet failure stress arising from stress concentrations developed in the sheets when under high strain.", "[0032] Impressing the selected indentation patterns on thin ceramic sheet can be accomplished in a number of different ways.", "For example, sufficiently thin ceramic sheet materials can be reformed through a process of superplastic deformation at high temperatures below their melting temperatures.", "[0033] However, more effective and economic sheet patterning can be achieved according to the invention through the process of reshaping unfired green sheet at or near room temperature prior to sintering to an integral ceramic film.", "Binder formulations useful for the tape-casting of powdered ceramics are known that offer sufficient plasticity and elongation to permit easy room-temperature pressing of many of the useful indentation patterns.", "Alternatively, green ceramic sheet formed by tape casting powder dispersions or suspensions together with thin thermoplastic base films can be processed by any of the various embossing or vacuum reforming methods useful for surface patterning plastics, with the base film providing any needed additional support for the green ceramic sheet throughout the reforming process.", "[0034] The following illustrative Example describes one low-temperature reforming method that may be used.", "EXAMPLE Production of Strain-Tolerant Ceramic Sheet [0035] A green polymer-bonded ceramic powder sheet is made from a zirconia powder as follows.", "A ceramic slip is first prepared by combining a yttria-stabilized zirconia powder (TZ-3Y powder from the Tosoh Corporation, Japan) with a vehicle consisting of a mixture of ethanol, butanol, propylene glycol and water.", "100 g of the zirconia powder free of contaminants is added to a previously prepared mixture of 36.4 g of ethanol, 8.8 g of 1-butanol, 2 g of propylene glycol, 2.5 g of distilled water, and 1 g of a liquid dispersant (Emphos PS-21A dispersant from the Witco Chemical Company).", "The resulting powder dispersion is transferred to a milling bottle and is vibration-milled for 72 hours using zirconia balls as the milling media.", "[0036] To remove coarse zirconia particles from the suspension and narrow the particle size distribution in the final slip, the milled suspension is processed through a double settling process wherein it is first allowed to settle for 72 hours and the liquid then separated from the sediment by decantation.", "The resulting slip is then allowed to settle for another 24 hours and separated from the sediment for final processing.", "[0037] The slip thus provided is next flocculated through the addition of an alcohol-acetic acid mixture consisting of 50% of glacial acetic acid and 50% of isopropyl alcohol by weight.", "This mixture is added to the slip in a proportion sufficient to provide 1 part of acetic acid for each 100 parts by weight of ceramic powder remaining after settling, and the acidified slip is then shaken to assure complete mixing.", "After the addition of the flocculant, film-forming additives consisting of about 3.5 parts by weight of a dibutyl pthalate liquid plasticizer and 6 parts by weight of a polyvinyl butyral powder binder are added to the slip for each 100 parts by weight of zirconia powder remaining after settling, with gentle shaking after each addition to achieve thorough mixing.", "The resulting slip has a viscosity suitable for tape casting.", "[0038] A flexible cohesive zirconia sheet is formed from this slip by casting it onto a thin methyl cellulose release layer previously applied to a flat casting surface.", "The release layer consists of a dried tape-cast methyl cellulose coating of about 0.0005 inch thickness formed from a 2% (wt.) aqueous solution of Dow K-75 Methocel® cellulose.", "The tape-cast layer thus provided provides a flexible green ceramic sheet layer after the removal of volatile slip vehicle components by drying.", "[0039] After this flexible ceramic sheet layer has been formed, a supporting acrylic polymer overlayer is tapecast over the ceramic sheet and dried.", "This overlayer is provided from an acrylate solution containing 71% of ethyl acetate solvent to which 25% of polymethylmethacrylate powder and 3.5% of dibutyl pthalate (Aldrich Chemical Company) have been added.", "The acrylate solution is tapecast and then dried to provide a flexible polymer film overcoating.", "This layer adheres well to the underlying ceramic sheet layer, providing a cohesive composite sheet consisting of the ceramic sheet and acrylate overcoating.", "This cohesive composite sheet is easily separated from the cellulose release layer after all layers have been completely dried.", "[0040] To shape a strain-tolerant zirconia sheet from the composite green ceramic sheet thus provided, a metal form with regularly spaced hexagonal cutouts is provided.", "This form consists of a metal grid about 0.6 mm in thickness incorporating hexagonal cutouts in a close-packed array made up of offset rows of hexagons forming a honeycomb pattern, with a row-to-row center spacing of 6.5 mm.", "The residual metal framework surrounding the cutouts provides separating ribs about 0.6 mm in width and 0.6 mm in height between each hexagon and its six neighboring hexagons.", "FIGS. 2 - 2 a of the drawing illustrate a metal form of this design, wherein a plurality of hexagonal cutouts 12 are arranged in close-packed array within form 10 .", "[0041] To form multi-directional corrugated zirconia sheet the metal form thus provided is placed on a vacuum table and the table and form are preheated to about 60° C. A section of the composite green ceramic sheet about 31 cm by 24 cm in size made as above described is then placed over the form and an insulating section of polymer foam board is placed over the sheet and form to allow them to reach uniform temperature.", "The vacuum table is then activated for about ten seconds, following which the vacuum is released and the green ceramic sheet is removed from the form and inspected.", "[0042] The multi-directionally corrugated sheet resulting from this reforming step is a regularly indented green ceramic sheet incorporating hexagonal indentations separated from each other by spacings corresponding to the spacings between adjacent hexagonal cutouts in the metal honeycomb form.", "This green sheet is trimmed to even rectangular shape with a rotary cloth cutter and then sintered in air on a refractory setter in an electric kiln operating at 1430° C. for a period of two hours.", "The fully sintered sheet is then removed from the kiln and examined.", "[0043] FIGS. 1 - 1 ( a ) of the drawing present a schematic top plan and a front elevational cross-sectional view, respectively, of a ceramic sheet 20 which has been fully sintered to set a hexagonal indentation pattern incorporating a plurality of hexagonal indentations 22 established during reforming of the green sheet substantially as above described.", "When made in accordance with this procedure the sintered sheet will be of zirconia-3 mole % yttria composition with a thickness of about 20 um, supporting an array of hexagonal indentations about 0.15 mm in depth with a row-to-row center spacing of about 4.5 mm between the rows of the hexagons.", "The unusually high multidirectional strain tolerance of this sheet is manifested by an easily discerned stretch or “give”", "in the sheet when manually stressed in the sheet plane.", "The strain tolerance of the free-standing sheet is measured to be in excess of 1% without cracking.", "[0044] Variations in the reforming procedure employed to process green ceramic sheets can be used to change the nature or extent of the indentation patterns developed.", "For example, using shorter vacuum forming times, e.g., of 1 to 3 or 4 seconds in duration, give shallower corrugations, while using a polyethylene sheet on top of the green ceramic sheet to increase vacuum retention, or using longer forming times, give deeper (higher) corrugations.", "[0045] As previously noted, however, attempting to address the problems of thermal stress through the use of widely spaced corrugations of excessive height or curvature, instead of shallow, closely spaced corrugations, limits strain tolerance and ultimate failure strength of the ceramic sheet.", "An illustrative example of this effect is provided by the hypothetical case of a bi-directionally corrugated yttria-stabilized zirconia (YSZ) sheet of about 40 micrometers thickness featuring a criss-crossing array of relatively large but abrupt corrugations or ridges.", "The corrugations would be offset 90 degrees from each other at a ridge spacing of approximately 1 cm, a ridge height of about 2 mm, and a ridge base width of about 1 mm, with a radius of curvature for the ridge edges of 0.4 mm.", "[0046] While the two-dimensional corrugations in this sheet would improve sheet strain tolerance in multiple directions in the sheet plane, free-standing ceramic sheet of this type will suffer crack damage at strains well below useful levels.", "Such cracking failures will most often occur at corrugation peak locations, due to the depth and spacing of the corrugations employed and the concentration of bending stresses at corrugation ridges.", "[0047] For the foregoing reasons, indentation patterns provided in accordance with the invention will have indentation populations along any axis in the plane of the sheet at least adequate to permit theoretical sheet elongations of 1% or greater in all directions within the plane of the sheet.", "Desirably, for sintered zirconia-based ceramic sheets, the corrugation or other indentation patterns will not incorporate curvature radii below about 2 mm or 100× the thickness of the sheet.", "Further, the corrugations or other indentations will preferably not exceed about 2 mm in height as measured from the base plane of the sheet.", "[0048] A particular advantage of the invention is that alternative indentation patterns adapted to specific applications for strain-tolerant ceramic sheets may be developed to meet particular needs.", "For example, where high flatness in selected sheet portions is required to meet special electrical contact or electrode processing requirements, sheets incorporating flat sections together with sections incorporating patterned indentations can be provided.", "[0049] [0049 ]FIG. 3 of the drawing illustrates one sheet design of this type, incorporating a multi-directionally corrugated or indented border portion 30 incorporating hexagonal indentations 32 surrounding a rectangular flat central section 34 .", "This design is particularly well adapted for applications wherein the sheet is to be edge-mounted in a surrounding frame.", "For a mounting of this type the flat central section of the sheet is isolated from undue stress in all directions in the sheet plane by the surrounding, highly strain tolerant indented border section.", "Further, the strain-tolerant edge portions facilitate edge mounting since gas-tight edge seals requiring larger sheet deformations can be accommodated with a lower risk of sheet failure.", "[0050] The importance of high multi-directional strain tolerance in ceramic sheets intended for use as fuel cell electrolytes can be better appreciated from a consideration of the damaging effects of thermal stress on the components of fuel cells, especially fuel cells that are subjected to frequent thermal cycling.", "One fuel cell design to be considered incorporates a yttria-stabilized zirconia electrolyte sheet mounted in a relatively massive surrounding frame that functions as a sheet separator and enclosure for fuel or oxidant gases to be supplied to the sheet.", "Such frames will be of much higher thermal mass than the electrolyte sheet and its supported electrode layers.", "[0051] In some designs the electrolyte/electrode sheets will be mounted in these frames so that they will be substantially unstressed at fuel cell operating temperatures.", "If a fuel cell operating temperature of 800 C. is specified and the cell is turned off, the electrode/electrolyte sheet will cool to ambient temperatures much more rapidly than the frame.", "In fact, it can be determined from the known thermal expansion coefficient of yttria-stabilized zirconia (110×10 −7 /° C.) that a strain as high as 0.9% can be developed in an electrolyte/electrode sheet mounted in such a frame at the point of maximum sheet/frame temperature differential during the cooling process.", "This strain can readily be accommodated by the strain-tolerant electrolyte sheets of the invention.", "[0052] Other corrugation or indentation designs that are free of straight ridge or flat lines and thus provide high strain tolerance in accordance with the invention are illustrated by line representations in FIGS. 5 b - 5 f of the drawing.", "In each of these drawings the lines indicate the outlines of the selected indentations, and straight lines traversing the entire indentation pattern are entirely absent.", "[0053] The imprinting of green ceramic sheets with any of these various indentation patterns can readily be carried out in a continuous process, and can be accomplished at any one of a number of different points in the sheet forming process ranging from the time the green ceramic sheet is first cast to the point at which the dried green sheet is ready for sintering.", "Further, any of the various indentation patterns having the required shape and frequency characteristics may be used in combination with sheet configurations other than strictly planar configurations, including tubular or dome configurations, to increase multi-axial strain tolerance in tubular or other non-planar fuel cell designs.", "[0054] For some applications, anisotropic corrugation patterns may be useful to impart anisotropic strain tolerance and stiffness to the sheet.", "Depending upon the particular thermal and mechanical environment in which the ceramic sheet is to be used, higher strain tolerance in one direction than another may be required.", "One example of such an environment would be a fuel cell design wherein steeper thermal gradients are expected along one axis than along other axes, due to irregular gas flow patterns across the electrolyte.", "The use of different indentation patterns at different locations on a single sheet may also be useful to compensate for uneven temperature distributions within the cell.", "These and numerous other modifications of the products, materials, processes and apparatus hereinabove described will be resorted to by those skilled in the art within the scope of the appended claims." ]
CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of application Ser. No. 11/023,361 filed Dec. 29, 2004 (pending), which is a continuation of application Ser. No. 08/487,778 filed Jun. 7, 1995 (abandoned). Each of the foregoing applications is incorporated by reference in its entirety. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] This invention relates to communication systems used by individuals for general tele-writing, sketching and drawing of hand written information, to be transmitted to other individuals via computer systems. In particular it relates to computer workstations comprised of electrical and mechanical devices for the input, computation, and output of data, resulting an integrated ergonomically designed human-computer interface system. [0004] 2. Description of the Prior Art [0005] In the following, a computer workstation is defined to be a combination of devices and apparatus, which may include computer hardware and software, that a person uses or operates during the performance various computing and communication tasks. These tasks includes, but is not limited to, technical calculations, business computations and local/remote communications. Prior art in this field includes many computer workstations and personal computers. Henceforth, a computer workstation will include personal computers, computer terminals, computer consoles, and like devices. The person operating the workstation will be referred to as the user. Display devices used in computer workstations can be classified into two broad categories. The first category is often referred to as direct-view display devices, in which the user, looks directly at the actual display screen, not projected light image from other components. Most of the display devices in the prior art belong to this category, examples include the Cathode Ray Tube (CRT), liquid crystal, and plasma panel displays. The other category is referred to as non-direct view or projected image displays, where examples include the optical CRT projector and some laser addressed liquid crystal projection devices. [0006] There are presently many computer workstations on the market, many having similar components and physical arrangements. The available workstations are very well known to those skilled in the workstation art. The majority of computer workstations have a CRT display device placed on the table or desk, a mouse unit, a computer unit, and an alphanumeric keyboard. The prior art CRT or other direct-view displays usually have the display screen at near vertical or near 45 degree screen inclinations. A graphic tablet is defined to be an electrical device, which repeatedly measures the position of a stylus, pen or a user's finger over a defined area, encodes the positions into a digital signal, and transmits the data to a computer. A stylus is defined to be any elongated pen-like object that can be used for writing or sketching, including the user's finger. The writing stylus is typically used to point, write, sketch, or draw onto the graphic tablet's active area, referred to as the encoding area. [0007] Prior art in computer workstations exist in various combinations of computers, display devices, and peripheral devices. However, the prior art fails to anticipate the importance of computer workstation with computer, graphic tablet, and display device, with inclined screen angle and its adjustability through large angles. U.S. Pat. No. 4,361,725 of Dagnelie discloses a teletext device having a graphic tablet and a CRT display at a screen inclination fixed near 45 degrees. However, the disclosure does not recognize display screen angle adjustability and does not teach a computing means of any type, which severely limits the usefulness of the device. U.S. Pat. No. 4,562,482 of Brown discloses a computerized executive workstation having a CRT display with a screen inclination angle of 50 degrees from the horizontal, during workstation operation. Although the CRT display can be retracted to a stored position below the work surface area, the teachings of Brown do not disclose a graphic tablet and do not disclose screen angle adjustability. These shortcomings restrict the workstation an operation without graphic input. The U.S. Pat. No. 4,668,026 of Lapeyre and Gundlach discloses a computer terminal cabinet for glare reduction, having a CRT display at an acute angle with the horizontal, a keyboard, and a printer. The reference teaches adjustable mounting only for glare reduction, and does not disclose a graphic tablet or a computer; thus also restricting the terminal to non-graphic input. U.S. Pat. No. 4,669,789 of Pemberton discloses a computer user's desk having a CRT monitor at about 60 degrees from the horizontal, a keyboard, and dual disk drives. This reference does not disclose a graphic tablet or screen angle adjustability to inclinations near the horizontal. Again, the prior art does not anticipate graphic input or screen angle adjustability for optimal stylus control. [0008] All the prior art of computer workstations, terminals or cabinets, of which the above is representative, disclose either display screens near vertical orientation, disclose fixed acute inclinations, or limited screen angle adjustability for glare reduction. No prior art can be found that disclose screen angle adjustability from horizontal to vertical, with a graphic tablet and computer. The prior art workstations can be used in either the conventional manner or at a fixed acute screen angle, but not both. The prior art fails to recognize the importance of an ergonomically design graphic input workstation capable of adjusting between conventional orientation and graphic input mode of operation with stylus data entry and screen angle near the horizontal (about 30 degrees for horizontal). [0009] Although several graphic tablet and stylus devices are available in the market, they usually have been combined with a display device by electrical means only. The typical display and graphic tablet combination has an opaque tablet laying horizontally on the desk or table next to the display device, connected by an electrical cable. Some graphic tablet prior art includes a transparent tablet placed over the display screen, but typically the screen orientation is near vertical. Although this arrangement works satisfactory for general purpose computer processing, it has some definite shortcomings when high resolution graphic processing is attempted. This is important because today software is becoming more graphic intensive than ever before. [0010] An important problem exists if the screen angle is near vertical. The user's hand and wrist must bend to an uncomfortable position to write or sketch on the tablet-display surface. In addition, if the screen is at eye level, as with most prior art, the user's arm must be raised and held at position that will become very tiresome to the user, if used for a significant amount of time. The above is not just a matter of convenience. These shortcomings have severely restricted the use of standard graphic tablet input devices in the marketplace. This is one reason that the mouse input device has found wide spread use as a graphic input device for computer workstations and personal computers. Specifically, the mouse unit slides over the work table or desk, providing a support for the user's hand and arm. However, the mouse graphic input devices also have several disadvantages. First, it is difficult for the user to write, sketch, or draw with a mouse, because the device is too large and bulky to act as a pen or stylus. Secondly, the device must have a clear area on the table or desk for the unit to slide. This is valuable work space that some workstations cannot afford to lose. [0011] Prior art workstations are inherently limited in their graphic interaction capabilities. The use of mice, joysticks, trackballs, and touch panels all have limitations for entering positional and functional data. For example, Computer-Aid Design (CAD) and Computer-Aided Design and Drafting (CADD) applications require precise and natural drawing and pointing means. An engineer or draftsman must be able to work at their workstation all day without great mental or physical fatigue. The prior art also does a poor job at providing a fatigue free workstation. In the area of teleconferencing applications, the computer workstation must be capable of real-time graphic and voice communications. The prior art workstations do not provide the means to accomplish that type of communications. In addition, conventional prior art workstations do not provide the ergonomically designed hardware support necessary for real-time electronic mail communications, while connected to either in Local Area Network communication means or remote communication means. SUMMARY OF THE INVENTION [0012] The disclosed invention solves the shortcomings of the prior art by arranging the standard workstation components so that it results in an integrated ergonomically designed universal workstation. The primary feature of the workstation is that its display device is oriented so that its screen angle is inclined at an angle. A transparent graphic tablet or stylus encoding means is placed over the display screen such that tablet or encoding area is parallel to the screen and above with a minimum space between them. Thus the tablet and screen appear to be one surface to the user. The display and tablet combination can be made to be adjustable through a multiplicity of screen angles. When the user writes with the stylus onto the tablet-surface and the surface is oriented at an angle of about 30 degrees, a natural writing and display surface exits, which provides a surprisingly synergistic and natural man-computer interface. In addition, the same workstation can be used for standard personal computing. [0013] Accordingly, the present invention has for its first object a computer workstation with a display device oriented at an inclined angle near the horizontal such that the user can write, sketch or draw on the display screen-tablet surface it a natural manner, where it results in a new and surprising telewriting, teledrawing, and voice-graphics conferencing system. [0014] Another important object of this invention is to provide an ergonomically designed computer workstation integrating text, graphics, and voice means for the purpose of general purpose computing and communications. [0015] A still another important object of this invention is to provide for a human-computer interface that results in a natural, easy to use, and useful computer workstation, personal computer, computer terminal, personal workstation, and/or computer console. [0016] A further object of this invention is to allow precise hand controlled stylus pointing, sketching, writing, or drawing functions by a user for data entry into a computer means, computer network, distributed network, or communication system. [0017] A still further object of this invention is to provide a workstation with graphic input and output means integrated with two way telephone voice means, such that real-time teleconferencing is made possible from the same workstation herein. [0018] Another important object of this invention is to provide a computer based workstation capable of real-time electronic mail functions. This would involve communicating alphanumeric text, graphics, and images to remote locations, and having a capability of transmitting the user's hand writing, including his or hers personal signature, via electronic mail messages. [0019] A further object of this invention is to provide an improved computer workstation for Computer-Aided Design and Computer-Aided Design and Drafting applications, as well as general purpose high resolution graphic image rendering systems. [0020] Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0021] FIG. 1 is a perspective view of the computer workstation in accordance with the present invention. [0022] FIG. 2 is a right side view of a CRT monitor embodiment of the invention, showing a hidden view, an exploded view and a break away view. [0023] FIG. 3 is a right side view of the flat panel display embodiment of the invention, showing hidden view, an exploded view and a break away view. [0024] FIGS. 4A and 4B are a flow chart of one application of the invention showing the sequence of the stored program events during the operation of the computer workstation. DETAILED DESCRIPTION [0025] The disclosed invention can be described with reference to the perspective view of FIG. 1 , which shows one possible embodiment. The components of the computer workstation may be arranged in several different embodiments. In FIG. 1 , a table support 26 physically supports a display device 22 , a transparent graphic tablet surface area 18 , a stylus 14 , a computer keyboard unit 12 , a mouse unit 15 and a computing means 24 . The table support 26 may be a standard desk or pedestal, modified to physically support the above components, or it may be a specially design structure. All display devices define a display screen of a finite area. The display device 22 has a display screen 16 , which is located under the graphic tablet surface 18 and is of equivalent size, as indicated in the figure. The display screen is inclined at an angle between the horizontal and 45 degrees. The angle of inclination is adjustable through a wide range of angles. The display device 22 has control circuitry which may internal to the screen housing or located some distance away. The control circuitry may have one or more microprocessors associated with it. [0026] The graphic tablet surface 18 may consist of a thin layer of a transparent material such as indium tin oxide or other suitable material; thus it cannot be distinguished for the display screen 16 in FIG. 1 , but can be seen in FIGS. 2 and 3 in exploded view. The stylus 14 has an electrical cable 20 connecting it to the computing means 24 . The graphic tablet surface 18 , the stylus 14 the stylus-computer cable 20 and its control electronics make up a stylus position encoding means. The control electronics is typically located on a printed circuit card inside the computing means. Stylus encoding means are well known to those skilled in the art. The mouse unit is comprised of a hand unit and electrical cable, which is connected to the computing mean's serial port or bus interface. [0027] A telephone means 28 may be located on table support means near the display device and keyboard. The addition of the telephone means to the computer workstation provides for both voice and data communications, simultaneously. The telephone means may be connected to the computing means 24 via an electrical telephone-computer cable 29 . Specific circuitry in the computing means may integrate the voice signals with text/graphic data, well known to those skilled in the art. The computing means may be connected to an external communication means for transmitting and receiving data to and from a communications network 52 . The electrical connection to the communications network is via an external communications cable 49 . The communications network 52 is defined to be any appropriate communication system or network, in which data is transmitted and/or received to and from local or remote devices. Examples of such a communication network include the conventional telephone system, private telephone exchanges, computer local area networks, wide area networks, RS-232 serial interface, and many other types of communication systems. The telephone means 28 may be a speaker-type telephone, where the hands of the user are free to type on the keyboard or to write with the hand-held stylus. In an alternative embodiment, the telephone means may be connected directly to the communications network without going through the computer means. In an alternative embodiment, the computing means' functions may be incorporated into the display control circuitry. [0028] The computer keyboard unit 12 may be a standard alphanumeric type keyboard or a special application specific keyboard design. As shown in FIG. 1 , the keyboard unit is mounted in front of the workstation for easy access by the user. The keyboard is electrically connected to the computer with a cable in the standard manner, well known to those skilled in the art. The computing means 24 may be located in several different positions, but a convenient position may be vertical mounted under the table support 26 , as shown in the figure. [0029] FIG. 2 shows a right side view of one embodiment of the computer workstation, embodied with a CRT display monitor 40 , which is a specific type of display device. For clarity, this figure does not show the telephone means 28 , but it does show the telephone-computer cable 29 . Some elements of the figure are shown with hidden lines and other elements are shown in a break-a-way view. [0030] The computer workstation 10 may be realized with several types of computers or processors, having a wide range of processing powers, capabilities and sizes. Typically, the computing means 24 will have a central processing unit, internal memory, arithmetic logic unit, internal data bus, memory bus, device controllers, and other component well known to those skilled in the art. The computing means 24 will also process stored programs, algorithms and software stored on a computer readable medium, including but not limited to machine language, operating system, assembly languages, high level computational languages, and application software. The software may include text and graphic primitive programs to assist in the generation and manipulation of text and graphic workstation functions. Such software is known to those skilled in the field. [0031] The means to encode a stylus position over the tablet area into electrical signals can be accomplished by several techniques. Among the prior art of encoding means are (1) measurement of x and y time delays via surface acoustic wave, (2) surface resistive sheet, (3) membrane pressure, (4) magnetic field means and (5) air acoustic means. In some embodiments, the tablet surface maybe a thin film applied to the display screen. In other embodiments, the tablet or encoding area may represent an area on the display screen, without a physical embodiment; i.e., air space between sensors. There are many types of graphic tablets that are presently on the market, including the SummaSketch® from Summagraphics Corporation, E-Z Image' from Ovonic Systems Inc., or Scriptelm from Scriptel Corporation. Typically, the stylus position is measured at a rate of about 100-500 points/second in both the x and y directions over the tablet's active area. The tablet electronics, located near the tablet, in the stylus, or on the tablet-computer interface card, converts these measurements into a digital code (encoded) and arranged into digital words or bytes (typically, 8 or 16 bits long). The resolutions of these devices are in the 200-300 dots/inch range. [0032] As presented in FIG. 2 , the graphic tablet means is comprised of the graphic tablet surface 18 and the stylus 14 elements. They are presented in an exploded view, in order to show the reader the distinction between the tablet and the display screen 16 . The space shown between elements 16 and 18 would not be apparent in the disclosed embodiment. The stylus 14 is shown with the cable 20 connecting it the computing means. The term graphic tablet and stylus encoding means are equivalent. Depending on the type of graphic tablet employed, the cable may not be necessary. The cable can be removed if the stylus contains small batteries for electrical power. Electrical cable 20 connects the graphic tablet to the computing means 24 for control. The electrical interface between the tablet and computing means can be a serial RS-232 interface, a parallel bus interface, or other standard computer-device interfaces. In FIG. 2 , at least one electrical cable 42 connects the CRT monitor 40 to the computing means 24 for control of the display functions. The electrical interface is of the standard type well known to those skilled in the display terminal or workstation field. Typically, either digital TTL signals (representing video) or analog RGB video signals are provided to the CRT monitor. [0033] Many types of CRT display monitors could be used in the workstation, but it is preferred that a relatively high resolution (70 dots/inch or higher) flat screen type be used. One possible candidate CRT that is presently available is the Zenith' Data System's Model ZCM-1490 Flat Screen CRT Monitor. This monitor is a color CRT display capable of displaying the IBM® V GA Standard 620×480 pixels at a center screen pitch of 0.28 millimeters. This resolution is sufficient for reasonable quality graphics. The main advantage of the monitor is its flat screen. For the invention disclosed here, the flat screen results in a natural writing surface, when combined with a graphic tablet. Other curved surface CRTs could be used, but a flat screen is a preferred embodiment. Although either monochrome or color display could be used, color displays are preferred, because they can produce a high brightness background color, for example white. A bright display background is important in order to reduce the perceived glare from the display-tablet screen. Of course, color displays are also preferred because of improved human information recognition, well known in the human factors field. [0034] Instead of a CRT display monitor, the workstation may be embodied with a flat panel display device. One possible embodiment is shown in shown in FIG. 3 with flat panel display device 27 . Flat panel displays devices include electroluminescent, liquid crystal, plasma, electrochromic, and electrophoretic display technologies. The primary characteristic of these type displays is the relatively thin structure with a lack of bulkiness. This lack of depth is an advantage since it reduces the mass and volume of the display device. This makes it easier to manufacture the computer workstation, resulting in a lower cost and an improved ergonomically designed workstation. [0035] Since a relatively high resolution display device is required in this system, the active matrix liquid crystal display (LCD) panel is a preferred flat panel technology of choice. The advantages of LCD panels are their low power, light weight, VGA resolution, and the possibility of color. Presently, the disadvantages of LCDs are their high cost, low brightness, low contrast, and limited grey scale and color. The other display technologies have even greater limitations, making it difficult to realize a useful display device. This however, may change in the future when improvements in flat panel display technology will undoubtedly be made. The electrical signals between a flat panel display and the computing means, carried by cable 42 of FIG. 3 , differ from that of the CRT. Flat panel displays are typically driven by matrix addressing techniques, requiring significant circuitry to be located at or near the panel. Data to be transferred between the display and the computing means will consist of digital words containing a number of bits for x and y addresses, write and erase data, color information, scan data, etc. Such interfaces are well known to those skilled in the art of display technology. [0036] The other elements of FIG. 3 , with like element numbers, are equivalent to those of FIG. 2 . The preferred workstation embodiment is the one using flat panel display device 27 and display orientation adjustment means 50 as shown in FIG. 3 . One reason for this preference is the ease of adjusting means and potentially better quality display. However, the low cost of CRT monitors may be an advantage if the cost continues to be less than equivalent flat panel displays. [0037] FIGS. 4A and 4B presents a flow chart of one possible implementation of the software that would be executed in the computing means, including central processor unit or control circuitry. If a computer is embodied in the invention, the software would reside in stored programs residing in memory of the computer. The memory may be semiconductor, magnetic, optical or other memory types. The sequence starts with the power-on switch selection, which starts the power-up initialization program 60 . The term program, as used here, is equivalent to an algorithm or routine, implemented in computer software. The next program step is the systems diagnostics and checkout program 62 that has either of two outputs: PASS or FAIL. If any of the tested components FAIL the test, data is sent to the system error report 64 program. If the system passes, the operator is asked to select the mode of operation 66 , via the keyboard, mouse or graphic tablet. If a terminal emulation mode is selected, the mode is initialized 70 . The terminal mode is defined to be an operational mode where the workstation acts as a conventional computer terminal or communications terminal. If it is to act as a communications terminal, voice data from the telephone means may be communicated as well as text and graphic data. The user is asked whether the voice communications 72 option is desired; if so, a program to control the voice communication is initiated. In either case, a terminal communication program and modem program 80 is initialized. Next, the terminal mode program is set up 92 and the terminal application program is loaded 94 . Exit from the terminal mode is allowed, along with operation stop and power off. [0038] If the workstation mode is selected in element 66 of FIG. 4A , the operating system is booted 68 . The user is then asked to select either a stand-alone or a network mode 74 . If a stand alone mode is chosen, that mode is initialized 82 , a windowing environment program may be loaded 90 , and setup for an application program is accomplished 96 . If the network mode is selected, the network communication's programs are initialized 76 , and the user is asked whether the voice communication option is selected 84 . If so, the voice communication program is initialized, which notifies the program that simultaneous voice communications via the telephone means will take place, with both text and graphic data communications. The voice signals may be integrated with the digital text and graphics data, or it may be transmitted and received via a separate cable to the communications network. A Local Area Network (LAN) or a remote communications programs are then loaded 88 . If necessary, certain data or programs may be downloaded 98 to the workstation from a remote host or workstation. Elements 88 and 98 both input into the load window environment program 90 . [0039] Following element 96 of FIG. 4B , the user is given the opportunity of selecting and initializing the memory and I/O devices 100 , which are available to the workstation. The required application program or programs are then loaded into the workstation memory. A wide variety of application programs could be loaded, including, but not limited to, a realtime tele-writing conferencing program 106 , CAD/CADD application programs 108 , word processing and/or desktop publishing programs 110 , business/finance application programs 102 , and scientific and engineering application programs 104 . The user can exit from the application program or go to another application setup 112 . The user can also either exit the operating mode 114 or go to the mode of operation selection element 66 . If the exit from the operating mode is selected, the system stop and power-off switch can be selected. [0040] The scope of the invention disclosed here should be determined by the appended claims and their legal equivalents, rather than by the examples given above.
A man-computer-man communications system, including a computer workstation ( 10 ), which is comprised of a display device ( 22 ), graphic tablet ( 18 ), stylus ( 14 ), computer unit ( 24 ), and display device screen ( 16 ) located at convenient locations. The active area of the graphic tablet is a transparent surface area ( 18 ), which is coincident to the display screen and is approximately the same size as the display screen. The graphic tablet device may include active or passive stylus ( 14 ). A keyboard unit ( 12 ) and telephone unit ( 28 ) may be added to the workstation. An external communications system may be added to transmit and receive data to or from remote computers or other workstations. The computer unit ( 24 ) controls the operation of the workstation and external communications.
Identify the most important claim in the given context and summarize it
[ "CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of application Ser.", "No. 11/023,361 filed Dec. 29, 2004 (pending), which is a continuation of application Ser.", "No. 08/487,778 filed Jun. 7, 1995 (abandoned).", "Each of the foregoing applications is incorporated by reference in its entirety.", "BACKGROUND OF THE INVENTION [0002] 1.", "Field of the Invention [0003] This invention relates to communication systems used by individuals for general tele-writing, sketching and drawing of hand written information, to be transmitted to other individuals via computer systems.", "In particular it relates to computer workstations comprised of electrical and mechanical devices for the input, computation, and output of data, resulting an integrated ergonomically designed human-computer interface system.", "[0004] 2.", "Description of the Prior Art [0005] In the following, a computer workstation is defined to be a combination of devices and apparatus, which may include computer hardware and software, that a person uses or operates during the performance various computing and communication tasks.", "These tasks includes, but is not limited to, technical calculations, business computations and local/remote communications.", "Prior art in this field includes many computer workstations and personal computers.", "Henceforth, a computer workstation will include personal computers, computer terminals, computer consoles, and like devices.", "The person operating the workstation will be referred to as the user.", "Display devices used in computer workstations can be classified into two broad categories.", "The first category is often referred to as direct-view display devices, in which the user, looks directly at the actual display screen, not projected light image from other components.", "Most of the display devices in the prior art belong to this category, examples include the Cathode Ray Tube (CRT), liquid crystal, and plasma panel displays.", "The other category is referred to as non-direct view or projected image displays, where examples include the optical CRT projector and some laser addressed liquid crystal projection devices.", "[0006] There are presently many computer workstations on the market, many having similar components and physical arrangements.", "The available workstations are very well known to those skilled in the workstation art.", "The majority of computer workstations have a CRT display device placed on the table or desk, a mouse unit, a computer unit, and an alphanumeric keyboard.", "The prior art CRT or other direct-view displays usually have the display screen at near vertical or near 45 degree screen inclinations.", "A graphic tablet is defined to be an electrical device, which repeatedly measures the position of a stylus, pen or a user's finger over a defined area, encodes the positions into a digital signal, and transmits the data to a computer.", "A stylus is defined to be any elongated pen-like object that can be used for writing or sketching, including the user's finger.", "The writing stylus is typically used to point, write, sketch, or draw onto the graphic tablet's active area, referred to as the encoding area.", "[0007] Prior art in computer workstations exist in various combinations of computers, display devices, and peripheral devices.", "However, the prior art fails to anticipate the importance of computer workstation with computer, graphic tablet, and display device, with inclined screen angle and its adjustability through large angles.", "U.S. Pat. No. 4,361,725 of Dagnelie discloses a teletext device having a graphic tablet and a CRT display at a screen inclination fixed near 45 degrees.", "However, the disclosure does not recognize display screen angle adjustability and does not teach a computing means of any type, which severely limits the usefulness of the device.", "U.S. Pat. No. 4,562,482 of Brown discloses a computerized executive workstation having a CRT display with a screen inclination angle of 50 degrees from the horizontal, during workstation operation.", "Although the CRT display can be retracted to a stored position below the work surface area, the teachings of Brown do not disclose a graphic tablet and do not disclose screen angle adjustability.", "These shortcomings restrict the workstation an operation without graphic input.", "The U.S. Pat. No. 4,668,026 of Lapeyre and Gundlach discloses a computer terminal cabinet for glare reduction, having a CRT display at an acute angle with the horizontal, a keyboard, and a printer.", "The reference teaches adjustable mounting only for glare reduction, and does not disclose a graphic tablet or a computer;", "thus also restricting the terminal to non-graphic input.", "U.S. Pat. No. 4,669,789 of Pemberton discloses a computer user's desk having a CRT monitor at about 60 degrees from the horizontal, a keyboard, and dual disk drives.", "This reference does not disclose a graphic tablet or screen angle adjustability to inclinations near the horizontal.", "Again, the prior art does not anticipate graphic input or screen angle adjustability for optimal stylus control.", "[0008] All the prior art of computer workstations, terminals or cabinets, of which the above is representative, disclose either display screens near vertical orientation, disclose fixed acute inclinations, or limited screen angle adjustability for glare reduction.", "No prior art can be found that disclose screen angle adjustability from horizontal to vertical, with a graphic tablet and computer.", "The prior art workstations can be used in either the conventional manner or at a fixed acute screen angle, but not both.", "The prior art fails to recognize the importance of an ergonomically design graphic input workstation capable of adjusting between conventional orientation and graphic input mode of operation with stylus data entry and screen angle near the horizontal (about 30 degrees for horizontal).", "[0009] Although several graphic tablet and stylus devices are available in the market, they usually have been combined with a display device by electrical means only.", "The typical display and graphic tablet combination has an opaque tablet laying horizontally on the desk or table next to the display device, connected by an electrical cable.", "Some graphic tablet prior art includes a transparent tablet placed over the display screen, but typically the screen orientation is near vertical.", "Although this arrangement works satisfactory for general purpose computer processing, it has some definite shortcomings when high resolution graphic processing is attempted.", "This is important because today software is becoming more graphic intensive than ever before.", "[0010] An important problem exists if the screen angle is near vertical.", "The user's hand and wrist must bend to an uncomfortable position to write or sketch on the tablet-display surface.", "In addition, if the screen is at eye level, as with most prior art, the user's arm must be raised and held at position that will become very tiresome to the user, if used for a significant amount of time.", "The above is not just a matter of convenience.", "These shortcomings have severely restricted the use of standard graphic tablet input devices in the marketplace.", "This is one reason that the mouse input device has found wide spread use as a graphic input device for computer workstations and personal computers.", "Specifically, the mouse unit slides over the work table or desk, providing a support for the user's hand and arm.", "However, the mouse graphic input devices also have several disadvantages.", "First, it is difficult for the user to write, sketch, or draw with a mouse, because the device is too large and bulky to act as a pen or stylus.", "Secondly, the device must have a clear area on the table or desk for the unit to slide.", "This is valuable work space that some workstations cannot afford to lose.", "[0011] Prior art workstations are inherently limited in their graphic interaction capabilities.", "The use of mice, joysticks, trackballs, and touch panels all have limitations for entering positional and functional data.", "For example, Computer-Aid Design (CAD) and Computer-Aided Design and Drafting (CADD) applications require precise and natural drawing and pointing means.", "An engineer or draftsman must be able to work at their workstation all day without great mental or physical fatigue.", "The prior art also does a poor job at providing a fatigue free workstation.", "In the area of teleconferencing applications, the computer workstation must be capable of real-time graphic and voice communications.", "The prior art workstations do not provide the means to accomplish that type of communications.", "In addition, conventional prior art workstations do not provide the ergonomically designed hardware support necessary for real-time electronic mail communications, while connected to either in Local Area Network communication means or remote communication means.", "SUMMARY OF THE INVENTION [0012] The disclosed invention solves the shortcomings of the prior art by arranging the standard workstation components so that it results in an integrated ergonomically designed universal workstation.", "The primary feature of the workstation is that its display device is oriented so that its screen angle is inclined at an angle.", "A transparent graphic tablet or stylus encoding means is placed over the display screen such that tablet or encoding area is parallel to the screen and above with a minimum space between them.", "Thus the tablet and screen appear to be one surface to the user.", "The display and tablet combination can be made to be adjustable through a multiplicity of screen angles.", "When the user writes with the stylus onto the tablet-surface and the surface is oriented at an angle of about 30 degrees, a natural writing and display surface exits, which provides a surprisingly synergistic and natural man-computer interface.", "In addition, the same workstation can be used for standard personal computing.", "[0013] Accordingly, the present invention has for its first object a computer workstation with a display device oriented at an inclined angle near the horizontal such that the user can write, sketch or draw on the display screen-tablet surface it a natural manner, where it results in a new and surprising telewriting, teledrawing, and voice-graphics conferencing system.", "[0014] Another important object of this invention is to provide an ergonomically designed computer workstation integrating text, graphics, and voice means for the purpose of general purpose computing and communications.", "[0015] A still another important object of this invention is to provide for a human-computer interface that results in a natural, easy to use, and useful computer workstation, personal computer, computer terminal, personal workstation, and/or computer console.", "[0016] A further object of this invention is to allow precise hand controlled stylus pointing, sketching, writing, or drawing functions by a user for data entry into a computer means, computer network, distributed network, or communication system.", "[0017] A still further object of this invention is to provide a workstation with graphic input and output means integrated with two way telephone voice means, such that real-time teleconferencing is made possible from the same workstation herein.", "[0018] Another important object of this invention is to provide a computer based workstation capable of real-time electronic mail functions.", "This would involve communicating alphanumeric text, graphics, and images to remote locations, and having a capability of transmitting the user's hand writing, including his or hers personal signature, via electronic mail messages.", "[0019] A further object of this invention is to provide an improved computer workstation for Computer-Aided Design and Computer-Aided Design and Drafting applications, as well as general purpose high resolution graphic image rendering systems.", "[0020] Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.", "BRIEF DESCRIPTION OF THE DRAWINGS [0021] FIG. 1 is a perspective view of the computer workstation in accordance with the present invention.", "[0022] FIG. 2 is a right side view of a CRT monitor embodiment of the invention, showing a hidden view, an exploded view and a break away view.", "[0023] FIG. 3 is a right side view of the flat panel display embodiment of the invention, showing hidden view, an exploded view and a break away view.", "[0024] FIGS. 4A and 4B are a flow chart of one application of the invention showing the sequence of the stored program events during the operation of the computer workstation.", "DETAILED DESCRIPTION [0025] The disclosed invention can be described with reference to the perspective view of FIG. 1 , which shows one possible embodiment.", "The components of the computer workstation may be arranged in several different embodiments.", "In FIG. 1 , a table support 26 physically supports a display device 22 , a transparent graphic tablet surface area 18 , a stylus 14 , a computer keyboard unit 12 , a mouse unit 15 and a computing means 24 .", "The table support 26 may be a standard desk or pedestal, modified to physically support the above components, or it may be a specially design structure.", "All display devices define a display screen of a finite area.", "The display device 22 has a display screen 16 , which is located under the graphic tablet surface 18 and is of equivalent size, as indicated in the figure.", "The display screen is inclined at an angle between the horizontal and 45 degrees.", "The angle of inclination is adjustable through a wide range of angles.", "The display device 22 has control circuitry which may internal to the screen housing or located some distance away.", "The control circuitry may have one or more microprocessors associated with it.", "[0026] The graphic tablet surface 18 may consist of a thin layer of a transparent material such as indium tin oxide or other suitable material;", "thus it cannot be distinguished for the display screen 16 in FIG. 1 , but can be seen in FIGS. 2 and 3 in exploded view.", "The stylus 14 has an electrical cable 20 connecting it to the computing means 24 .", "The graphic tablet surface 18 , the stylus 14 the stylus-computer cable 20 and its control electronics make up a stylus position encoding means.", "The control electronics is typically located on a printed circuit card inside the computing means.", "Stylus encoding means are well known to those skilled in the art.", "The mouse unit is comprised of a hand unit and electrical cable, which is connected to the computing mean's serial port or bus interface.", "[0027] A telephone means 28 may be located on table support means near the display device and keyboard.", "The addition of the telephone means to the computer workstation provides for both voice and data communications, simultaneously.", "The telephone means may be connected to the computing means 24 via an electrical telephone-computer cable 29 .", "Specific circuitry in the computing means may integrate the voice signals with text/graphic data, well known to those skilled in the art.", "The computing means may be connected to an external communication means for transmitting and receiving data to and from a communications network 52 .", "The electrical connection to the communications network is via an external communications cable 49 .", "The communications network 52 is defined to be any appropriate communication system or network, in which data is transmitted and/or received to and from local or remote devices.", "Examples of such a communication network include the conventional telephone system, private telephone exchanges, computer local area networks, wide area networks, RS-232 serial interface, and many other types of communication systems.", "The telephone means 28 may be a speaker-type telephone, where the hands of the user are free to type on the keyboard or to write with the hand-held stylus.", "In an alternative embodiment, the telephone means may be connected directly to the communications network without going through the computer means.", "In an alternative embodiment, the computing means'", "functions may be incorporated into the display control circuitry.", "[0028] The computer keyboard unit 12 may be a standard alphanumeric type keyboard or a special application specific keyboard design.", "As shown in FIG. 1 , the keyboard unit is mounted in front of the workstation for easy access by the user.", "The keyboard is electrically connected to the computer with a cable in the standard manner, well known to those skilled in the art.", "The computing means 24 may be located in several different positions, but a convenient position may be vertical mounted under the table support 26 , as shown in the figure.", "[0029] FIG. 2 shows a right side view of one embodiment of the computer workstation, embodied with a CRT display monitor 40 , which is a specific type of display device.", "For clarity, this figure does not show the telephone means 28 , but it does show the telephone-computer cable 29 .", "Some elements of the figure are shown with hidden lines and other elements are shown in a break-a-way view.", "[0030] The computer workstation 10 may be realized with several types of computers or processors, having a wide range of processing powers, capabilities and sizes.", "Typically, the computing means 24 will have a central processing unit, internal memory, arithmetic logic unit, internal data bus, memory bus, device controllers, and other component well known to those skilled in the art.", "The computing means 24 will also process stored programs, algorithms and software stored on a computer readable medium, including but not limited to machine language, operating system, assembly languages, high level computational languages, and application software.", "The software may include text and graphic primitive programs to assist in the generation and manipulation of text and graphic workstation functions.", "Such software is known to those skilled in the field.", "[0031] The means to encode a stylus position over the tablet area into electrical signals can be accomplished by several techniques.", "Among the prior art of encoding means are (1) measurement of x and y time delays via surface acoustic wave, (2) surface resistive sheet, (3) membrane pressure, (4) magnetic field means and (5) air acoustic means.", "In some embodiments, the tablet surface maybe a thin film applied to the display screen.", "In other embodiments, the tablet or encoding area may represent an area on the display screen, without a physical embodiment;", "i.e., air space between sensors.", "There are many types of graphic tablets that are presently on the market, including the SummaSketch® from Summagraphics Corporation, E-Z Image'", "from Ovonic Systems Inc., or Scriptelm from Scriptel Corporation.", "Typically, the stylus position is measured at a rate of about 100-500 points/second in both the x and y directions over the tablet's active area.", "The tablet electronics, located near the tablet, in the stylus, or on the tablet-computer interface card, converts these measurements into a digital code (encoded) and arranged into digital words or bytes (typically, 8 or 16 bits long).", "The resolutions of these devices are in the 200-300 dots/inch range.", "[0032] As presented in FIG. 2 , the graphic tablet means is comprised of the graphic tablet surface 18 and the stylus 14 elements.", "They are presented in an exploded view, in order to show the reader the distinction between the tablet and the display screen 16 .", "The space shown between elements 16 and 18 would not be apparent in the disclosed embodiment.", "The stylus 14 is shown with the cable 20 connecting it the computing means.", "The term graphic tablet and stylus encoding means are equivalent.", "Depending on the type of graphic tablet employed, the cable may not be necessary.", "The cable can be removed if the stylus contains small batteries for electrical power.", "Electrical cable 20 connects the graphic tablet to the computing means 24 for control.", "The electrical interface between the tablet and computing means can be a serial RS-232 interface, a parallel bus interface, or other standard computer-device interfaces.", "In FIG. 2 , at least one electrical cable 42 connects the CRT monitor 40 to the computing means 24 for control of the display functions.", "The electrical interface is of the standard type well known to those skilled in the display terminal or workstation field.", "Typically, either digital TTL signals (representing video) or analog RGB video signals are provided to the CRT monitor.", "[0033] Many types of CRT display monitors could be used in the workstation, but it is preferred that a relatively high resolution (70 dots/inch or higher) flat screen type be used.", "One possible candidate CRT that is presently available is the Zenith'", "Data System's Model ZCM-1490 Flat Screen CRT Monitor.", "This monitor is a color CRT display capable of displaying the IBM® V GA Standard 620×480 pixels at a center screen pitch of 0.28 millimeters.", "This resolution is sufficient for reasonable quality graphics.", "The main advantage of the monitor is its flat screen.", "For the invention disclosed here, the flat screen results in a natural writing surface, when combined with a graphic tablet.", "Other curved surface CRTs could be used, but a flat screen is a preferred embodiment.", "Although either monochrome or color display could be used, color displays are preferred, because they can produce a high brightness background color, for example white.", "A bright display background is important in order to reduce the perceived glare from the display-tablet screen.", "Of course, color displays are also preferred because of improved human information recognition, well known in the human factors field.", "[0034] Instead of a CRT display monitor, the workstation may be embodied with a flat panel display device.", "One possible embodiment is shown in shown in FIG. 3 with flat panel display device 27 .", "Flat panel displays devices include electroluminescent, liquid crystal, plasma, electrochromic, and electrophoretic display technologies.", "The primary characteristic of these type displays is the relatively thin structure with a lack of bulkiness.", "This lack of depth is an advantage since it reduces the mass and volume of the display device.", "This makes it easier to manufacture the computer workstation, resulting in a lower cost and an improved ergonomically designed workstation.", "[0035] Since a relatively high resolution display device is required in this system, the active matrix liquid crystal display (LCD) panel is a preferred flat panel technology of choice.", "The advantages of LCD panels are their low power, light weight, VGA resolution, and the possibility of color.", "Presently, the disadvantages of LCDs are their high cost, low brightness, low contrast, and limited grey scale and color.", "The other display technologies have even greater limitations, making it difficult to realize a useful display device.", "This however, may change in the future when improvements in flat panel display technology will undoubtedly be made.", "The electrical signals between a flat panel display and the computing means, carried by cable 42 of FIG. 3 , differ from that of the CRT.", "Flat panel displays are typically driven by matrix addressing techniques, requiring significant circuitry to be located at or near the panel.", "Data to be transferred between the display and the computing means will consist of digital words containing a number of bits for x and y addresses, write and erase data, color information, scan data, etc.", "Such interfaces are well known to those skilled in the art of display technology.", "[0036] The other elements of FIG. 3 , with like element numbers, are equivalent to those of FIG. 2 .", "The preferred workstation embodiment is the one using flat panel display device 27 and display orientation adjustment means 50 as shown in FIG. 3 .", "One reason for this preference is the ease of adjusting means and potentially better quality display.", "However, the low cost of CRT monitors may be an advantage if the cost continues to be less than equivalent flat panel displays.", "[0037] FIGS. 4A and 4B presents a flow chart of one possible implementation of the software that would be executed in the computing means, including central processor unit or control circuitry.", "If a computer is embodied in the invention, the software would reside in stored programs residing in memory of the computer.", "The memory may be semiconductor, magnetic, optical or other memory types.", "The sequence starts with the power-on switch selection, which starts the power-up initialization program 60 .", "The term program, as used here, is equivalent to an algorithm or routine, implemented in computer software.", "The next program step is the systems diagnostics and checkout program 62 that has either of two outputs: PASS or FAIL.", "If any of the tested components FAIL the test, data is sent to the system error report 64 program.", "If the system passes, the operator is asked to select the mode of operation 66 , via the keyboard, mouse or graphic tablet.", "If a terminal emulation mode is selected, the mode is initialized 70 .", "The terminal mode is defined to be an operational mode where the workstation acts as a conventional computer terminal or communications terminal.", "If it is to act as a communications terminal, voice data from the telephone means may be communicated as well as text and graphic data.", "The user is asked whether the voice communications 72 option is desired;", "if so, a program to control the voice communication is initiated.", "In either case, a terminal communication program and modem program 80 is initialized.", "Next, the terminal mode program is set up 92 and the terminal application program is loaded 94 .", "Exit from the terminal mode is allowed, along with operation stop and power off.", "[0038] If the workstation mode is selected in element 66 of FIG. 4A , the operating system is booted 68 .", "The user is then asked to select either a stand-alone or a network mode 74 .", "If a stand alone mode is chosen, that mode is initialized 82 , a windowing environment program may be loaded 90 , and setup for an application program is accomplished 96 .", "If the network mode is selected, the network communication's programs are initialized 76 , and the user is asked whether the voice communication option is selected 84 .", "If so, the voice communication program is initialized, which notifies the program that simultaneous voice communications via the telephone means will take place, with both text and graphic data communications.", "The voice signals may be integrated with the digital text and graphics data, or it may be transmitted and received via a separate cable to the communications network.", "A Local Area Network (LAN) or a remote communications programs are then loaded 88 .", "If necessary, certain data or programs may be downloaded 98 to the workstation from a remote host or workstation.", "Elements 88 and 98 both input into the load window environment program 90 .", "[0039] Following element 96 of FIG. 4B , the user is given the opportunity of selecting and initializing the memory and I/O devices 100 , which are available to the workstation.", "The required application program or programs are then loaded into the workstation memory.", "A wide variety of application programs could be loaded, including, but not limited to, a realtime tele-writing conferencing program 106 , CAD/CADD application programs 108 , word processing and/or desktop publishing programs 110 , business/finance application programs 102 , and scientific and engineering application programs 104 .", "The user can exit from the application program or go to another application setup 112 .", "The user can also either exit the operating mode 114 or go to the mode of operation selection element 66 .", "If the exit from the operating mode is selected, the system stop and power-off switch can be selected.", "[0040] The scope of the invention disclosed here should be determined by the appended claims and their legal equivalents, rather than by the examples given above." ]