Automated check processing system and method

Abstract

A document processing system comprises an input receptacle for receiving documents. A transport mechanism receives the documents from the input receptacle and transports the documents past a full image scanner and a discrimination unit. An output receptacle receives the documents from the transport mechanism after being transported past the full image scanner and the discrimination unit. The full image scanner includes means for obtaining a full video image of said documents, means for obtaining a image of a selected area of said documents, and means for obtaining information contained in said selected area of said document. The discrimination unit includes means for determining the authenticity of said document. A system controller directs the flows of documents over the transport mechanism.

Claims

What is claimed is:

1. A check processing system comprising:

an input receptacle for receiving checks;

an image scanner;

a transport mechanism coupled to the input receptacle and transporting the checks past the image scanner at a rate in excess of 800 checks per minute;

an output receptacle for receiving the checks from the transport mechanism after being transported past the image scanner;

the image scanner being adapted to obtain images of the checks, the scanner further being adapted to optically recognize fields within the checks and to automatically extract information from the fields; and

automatic means for dispensing and distributing funds among financial accounts associated with the checks.

2. The check processing system of claim 1 wherein the output receptacle is a single bin.

3. The check processing system of claim 1 wherein the output receptacle is a plurality of bins.

4. The check processing system of claim 3, wherein one of the plurality of output bins is an off sort bin.

5. The check processing system of claim 1 further comprising a communications panel adapted to communicate operational instructions to a user.

6. The check processing system of claim 1 further comprising an interface adapted to communicate the images and field information with an outside accounting system.

7. The check processing system of claim 1 wherein the checks have wide and narrow dimensions and the checks are transported with their narrow dimension parallel to the direction of transport.

8. The check processing system of claim 7, wherein the output receptacle is a single bin.

9. The check processing system of claim 7, wherein the output receptacle is two bins.

10. The check processing system of claim 9, wherein one of the two bins is an off sort bin.

11. The check processing system of claim 7, wherein the output receptacle is a plurality of output bins.

12. The check processing system of claim 11, wherein one of the plurality of output bins is an off sort bin.

13. The check processing system of claim 1 wherein the checks have wide and narrow dimensions and the checks documents are transported with their wide dimension parallel to the direction of transport.

14. The check processing system of claim 1 further including means for authenticating presented customer identification prior to dispensing and distributing funds, wherein the customer identification comprises an electronic image containing information comprising the bank and identity of the customer.

15. The check processing system of claim 1 further including means for authenticating presented customer identification prior to dispensing and distributing funds, wherein the customer identification comprises a slip of paper containing information comprising the bank and identity of the customer.

16. The check processing system of claim 1 wherein the checks have first and second surfaces and the checkers are scanned on first and second surfaces.

17. The check processing system of claim 1 wherein the output receptacle comprises two bins.

18. The check processing system of claim 17 wherein one of the two bins is an off sort bin.

19. The check processing system of claim 1, further comprising a stacking wheel comprising flexible blades positioned to restack checks in the output receptacle.

20. The check processing system of claim 1, further comprising means for flagging checks meeting or failing to meet predetermined criteria.

21. The check processing system of claim 20, wherein the means for flagging documents flags a check by suspending the operation of the system, the system being halted so that the flagged check is located at a predetermined position within the system when the transport mechanism stops.

22. A check processing system at a financial institution, comprising:

an input receptacle receiving checks;

an image scanner that scans the checks to generate electronic check image tiles;

a transport mechanism that transports the checks from the input receptacle past the image scanner; and

means for electronically tagging the check image files with endorsement data for the financial institution.

23. The system of claim 22 wherein the transport mechanism transports the checks past the image scanner at a rate in excess of 800 checks per minute.

24. The system of claim 22 wherein the image scanner further obtains information from fields within the checks.

25. The system of claim 22 wherein the endorsement data tagged to the check image file comprises bank information.

26. The system of claim 22 further including an accounting system that receives the tagged check image files and updates a financial account associated with a customer depositing the checks.

27. The system of claim 26, further including:

means for accepting identification from the customer associated with the financial account; and

means for dispensing currency to the customer;

the accounting system updating the balance of the financial account with respect to the dispensed currency.

28. The system of claim 22 further including a user input device through which unrecognizable field information may be input.

29. The system of claim 22 further including an interface through which tagged check image files are output to other financial institutions for further processing.

30. A check processing method comprising the steps of:

receiving checks;

scanning each check with an image scanner to obtain images of the checks;

transporting the checks past the image scanner at a rate in excess of 800 checks per minute;

receiving the checks after being transported past the image scanner;

optically recognizing fields within the check images in order to automatically extract information from the fields; and

automatically dispensing and distributing funds among financial accounts associated with the checks.

31. The method of claim 30 wherein the checks have wide and narrow dimensions and the step of transporting comprises the step of transporting the checks with their narrow dimension parallel to a direction of transport.

32. The method of claim 30 wherein the checks have wide and narrow dimensions and the step of transporting comprises the step of transporting the checks with their wide dimension parallel to a direction of transport.

33. The method of claim 30 further including the step of authenticating customer identification prior to dispensing and distributing funds, wherein the customer identification comprises an electronic image containing information comprising the bank and identity of the customer.

34. The method of claim 30 further including the step of authenticating customer identification prior to dispensing and distributing funds, wherein the customer identification comprises a slip of paper containing information comprising the bank and identity of the customer.

35. The method of claim 30 wherein the checks have first and second surfaces and the step of scanning comprises the step of imaging both the first and second surfaces.

36. The method of claim 30, further comprising the step of flagging checks meeting or failing to meet predetermined criteria.

37. The method of claim 36, wherein the step of flagging comprises the step of suspending check transport so that the flagged check is located at a predetermined position.

38. A check processing method performed at a financial institution, comprising the steps of:

receiving checks;

scanning the checks with an image scanner to generate electronic check image files;

transporting the received checks past the image scanner; and

electronically tagging the check image files with endorsement data for the financial institution.

39. The method of claim 38 wherein the step of transporting comprises the step of transporting the checks past the image scanner at a rate in excess of 800 checks per minute.

40. The method of claim 38 further including the step of optically recognizing information from fields within the checks.

41. The method of claim 38 wherein the endorsement data tagged to the check image file comprises bank information.

42. The method of claim 38 further including the step of updating a financial account associated with a customer depositing the checks.

43. The method of claim 38, further including steps of:

accepting identification from the customer associated with the financial account; and

dispensing currency to the customer;

updating the balance of the financial account with respect to the dispensed currency.

44. The method of claim 38 further including a user input device through which unrecognizable field information may be input.

45. The method of claim 38 further including the step of outputting tagged check image files to other financial institutions for further processing.

Description

FIELD OF INVENTION

The present invention relates to document processing systems such as automatic teller machines and currency redemption machines.

SUMMARY OF THE INVENTION

The primary object of the invention is to provide a document and currency processing system capable of processing documents utilizing full image scanning and a currency discriminator.

It is a further object of the invention is to provide a document processing system capable of processing documents utilizing fill image scanning.

It is another object of the invention is to provide a currency processing system capable of processing currency utilizing a currency discriminator.

It is another object of the invention to provide a document processing system capable of processing all types of documents and interfacing with all types of outside accounting systems.

It is still another object of the invention to provide a document processing system which obtains information by performing full image scanning of documents and utilizes this information to determine additional information such as the value of the document;

It is yet another object of the invention to provide a document processing system which is coupled to an outside accounting system such that deposits and withdrawals from the outside accounting system are processed substantially immediately.

It is yet another object of the invention to provide a system where deposits are processed substantially immediately.

It is a further object of the invention to provide a document processing system whereby the full image of the scanned document can be communicated to a central office.

It is yet another object of the invention to provide a currency and document processing system which provides all the benefits of an automated teller machine.

Other aspects and advantages of the present invention will become apparent upon reading the following detailed description and in reference to the drawings.

In accordance with the present invention, the foregoing objectives are realized by providing a document processing system comprising an input receptacle for receiving documents; a transport mechanism receiving said documents from said input receptacle and transporting said documents past a full image scanner and a discrimination unit; an output receptacle for receiving said documents from said transport mechanism after being transported past said full image scanner and discrimination unit; said full image scanner including means for obtaining a full video image of said documents, means for obtaining a image of a selected area of said documents, and means for obtaining information contained in said selected area of said document; said discrimination unit including means for determining the authenticity of said document; and a system controller for directing the flows of documents on said transport mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a shows a block diagram of the components of a document and currency processing system with a single output bin according to principles of the present invention;

FIG. 1b is a perspective view of one embodiment of the processing system with a video screen and keyboard according to principles of the present invention;

FIG. 1c is a diagram of the document processing system with touch screen according to principles of the present invention;

FIG. 1d is a block diagram of the document processing system with touch screen and keyboard according to principles of the present invention;

FIG. 1e is a block diagram of the document processing system with dual output bins according to principles of the present invention;

FIG. 1f is a block diagram of the document processing system with a plurality of output bins according to principles of the present invention;

FIG. 1g is a block diagram of the document processing system without a discrimination unit and having a single output receptacle according to principles of the present invention;

FIG. 1h is a block diagram of the document processing system without a discrimination unit and having dual output receptacles according to principles of the present invention;

FIG. 1i is a block diagram of the document processing system without a discrimination unit and having a plurality of output receptacles according to principles of the present invention;

FIG. 1j is a cut-away view of the document processing systems showing three output bins;

FIG. 1k is a cut-away view of the document processing systems showing four output bins;

FIG. 1l is a cut-away view of the document processing systems showing six output bins,

FIG. 1m is a view of a document being scanned by the full image scanner in the wide dimension;

FIG. 1n is a view of a document being scanned by the full image scanner in the narrow dimension;

FIG. 1o is a view of a compact document processing system according to principles of the present invention;

FIG. 1p is a block diagram of the document processing system with modules to insert smart cards, dispense smart cards, and insert optical media according to principles of the present invention;

FIG. 1q illustrates the document processing system according to principles of the present invention;

FIG. 1r is a block diagram of the document processing system with coin sorter according to principles of the present invention;

FIG. 1s is a perspective view of a document processor system having two output bins;

FIG. 1t is a side view of an evaluation device depicting various transport rolls in side elevation according to one embodiment of the present invention;

FIGS. 1u-v are a diagrams of networks of full image scanners according to principles of the present invention;

FIGS. 1w-y are topological diagrams of networks of full image scanners according to principles of the present invention;

FIG. 2 shows a flowchart describing the operation of the document processing system according to principles of the present invention;

FIG. 3 is a block diagram of the full image scanner according to principles of the present invention;

FIG. 4a is a block diagram of the discrimination unit according to principles of the present invention;

FIGS. 4b-4d illustrate the scanning process of the discrimination unit according to principles of the present invention;

FIG. 4e illustrates one embodiment of size determining sensors;

FIG. 4f illustrates the operation of the scanning process in the discrimination unit according to principles of the present invention;

FIG. 5a and 5b are graphs illustrating the correlation of scanned and master patterns according to principles of the present invention;

FIG. 6 illustrates a multiple scanhead according to principles of the present invention;

FIG. 7 illustrates another embodiment of the multiple scanheads according to principles of the present invention;

FIG. 8 depicts another embodiment of the scanning system according to principles of the present invention;

FIG. 9 depicts another embodiment of the scanning system according to principles of the present invention;

FIG. 10 is a top view of a staggered scanhead arrangement according to principles of the present invention;

FIGS. 11a and 11b are flowcharts illustrating the operation of the discrimination unit according to principles of the present invention;

FIG. 12 shows a block diagram of a counterfeit detector according to principles of the present invention;

FIG. 13 is a flow diagram of the discrimination unit according to principles of the present invention;

FIG. 14 is a graphical representation of the magnetic data points generated by two types of currency according to principles of the present invention;

FIG. 15 shows a functional block diagram illustrating one embodiment of the currency discrimination unit according to principles of the present invention;

FIGS. 16a and 16b show a flowchart illustrating the steps in implementing the discrimination unit according to principles of the present invention;

FIG. 17 illustrate a routine for detecting the overlapping of bills according to principles of the present invention;

FIGS. 18a-18c show one embodiment of the document authenticating system in the discrimination unit according to principles of the present invention;

FIG. 19 shows a functional block diagram illustrating one embodiment of the document authenticating system according to principles of the present invention;

FIG. 20 shows a modified version of the document authenticating system according to principles of the present invention;

FIG. 21 shows the magnetic characteristics of bills;

FIG. 22 shows other magnetic characteristics of bills;

FIGS. 23 and 24 illustrate bills being transported across sensors according to principles of the present invention;

FIG. 25 is a flowchart illustrating the steps performed in optically determining the denomination of a bill according to principles of the present invention;

FIG. 26 is a flowchart illustrating the steps performed in optically determining the denomination of a bill based on the presence of a security thread according to principles of the present invention;

FIG. 27 is a flowchart illustrating the steps performed in optically determining the denomination of a bill based on the color of the security thread according to principles of the present invention;

FIG. 28 is a flowchart illustrating the steps performed in optically determining the denomination of a bill based on the location and color of the security thread according to principle of the prevent invention;

FIG. 29 is a flowchart illustrating the steps performed in magnetically determining the denomination of a bill according to principles of the present invention;

FIG. 30 is a flowchart illustrating the steps performed in optically denominating a bill and authenticating the bill based on thread location and/or color information;

FIG. 31 is a flowchart illustrating the steps performed in denominating a bill based on thread location and/or color information and optically authenticating the bill;

FIG. 32 is a flowchart illustrating the steps performed in optically determining the denomination of a bill and magnetically authenticating the bill according to principles of the present invention;

FIG. 33 is a flowchart illustrating the steps performed in magnetically determining the denomination of a bill and optically authenticating the bill according to principles of the present invention;

FIG. 34 is a flowchart illustrating the steps in denominating the bill according to principles of the present invention;

FIG. 35 is a flowchart illustrating the steps performed in denominating the bill both optically and magnetically according to principles of the present invention;

FIG. 36 is a flowchart illustrating the steps in denominating the bill magnetically and based on thread location according to principles of the present invention;

FIG. 37 is a flowchart illustrating the steps performed in denominating a bill optically, based on thread location and magnetically according to principles of the present invention;

FIG. 38 is a flowchart illustrating the steps performed in denominating a bill based on a first characteristic and authenticating it based on a second characteristic according to principles of the present invention;

FIGS. 39-47 illustrate alternative methods for denominating and/or authenticating according to principles of the present invention;

FIGS. 48a-48c illustrate control panels;

FIGS. 49a, 49b, 50a, 50b, 51a, 51b, and 52-53 illustrate alternate means for entering the value of no-call documents according to principles of the present invention;

FIG. 54 illustrates one embodiment of the control panel according to principles of the present invention;

FIG. 55 shows the touch screen according to principles of the present invention;

FIG. 56a is a flowchart of conducting a document transaction according to principles of the present invention;

FIGS. 56b, 56c, and 56d are flowcharts of the funds distribution algorithm according to principles of the present invention;

FIG. 56e is a flowchart of an alternate funds distribution algorithm according to principles of the present invention;

FIG. 56f is a flowchart of the coin sorting algorithm according to principles of the present invention;

FIG. 57a illustrates means for entering the value of a no-call document according to principles of the present invention;

FIG. 57b illustrates means for entering the value of a no-call document on a touch screen according to principles of the present invention;

FIG. 58 is perspective view of a disc-type coin sorter embodying the present invention, with a top portion thereof broken away to show internal structure;

FIG. 59 is an enlarged horizontal section taken generally along line 59--59 in FIG. 58;

FIG. 60 is an enlarged section taken generally along line 62--62 in FIG. 59, showing the coins in full elevation;

FIG. 61 is an enlarged section taken generally along line 63--63 in FIG. 59, showing in full elevation a nickel registered with an ejection recess;

FIG. 62 is a diagrammatic cross-section of a coin and an improved coin discrimination sensor embodying the invention;

FIG. 63 is a schematic circuit diagram of the coin discrimination sensor of FIG. 62;

FIG. 64 is a diagrammatic perspective view of the coils in the coin discrimination sensor of FIG. 62;

FIG. 65a is a circuit diagram of a detector circuit for use with the discrimination sensor of this invention;

FIG. 65b is a waveform diagram of the input signals supplied to the circuit of FIG. 65a;

FIG. 66 is a perspective view of an outboard shunting device embodying the present invention;

FIG. 67 is a section taken generally along line 67--67 in FIG. 66;

FIG. 68 is a section taken generally along line 68--68 in FIG. 66, showing a movable partition in a nondiverting position; and

FIG. 69 is the same section illustrated in FIG. 68, showing the movable portion in a diverting position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As illustrated in FIGS. 1a and 1b, a user deposits bills or documents into an input receptacle 16. By "currency", "documents", or "bills" it is meant to include not only conventional U.S. or foreign bills, such as $1 bills, but also to include checks, deposit slips, coupon and loan payment documents, food stamps, cash tickets, savings withdrawal tickets, check deposit slips, savings deposit slips, and all other documents utilized as a proof of deposit at financial institutions. It is also meant by the term "documents" to include loan applications, credit card applications, student loan applications, accounting invoices, debit forms, account transfer forms, and all other types of forms with predetermined fields. By "financial institution documents" it is meant to include all of the above documents with the exception of currency. A transport mechanism 18 transports the documents from the input receptacle 16 past a full image scanner 12, as the documents are illuminated by a light (not shown). The full image scanner 12, described in greater detail below, scans the full image of the document, recognizes certain fields within the document, and processes information contained within these fields in the document. For example, the full image scanner 12 may search for the serial number field when processing U.S. currency, determine the serial number once the field is located, and store the serial number for later use by the system. The system may also be used to capture any document image for electronic document display, electronic document storage, electronic document transfer, electronic document recognition (such as denomination recognition or check amount recognition) or any other processing function that can be performed using an electronic image.

Next, the transport mechanism 18 transports the document past a discrimination and authentication unit 14 which is also described in greater detail below. The discrimination and authentication unit 14 authenticates the document and, in the case of a bill, determines the denomination of the bill. On other documents, such as checks, the system may capture information such as the check amount, account number, bank number, or check number. The discrimination and authentication unit 14 also directs the transport unit 18 to place the document in the output receptacle 20 as described below.

A dispensing unit 22 dispenses funds to a user. For example, when the user is depositing currency in an account, the system has the capability to return all or part of a deposit back to the user in the form of bills, coins, or other media via the dispensing unit 22. The amount of payback to the user may be supplemented by funds from other accounts, as well, as described below. The dispensing unit 22 is capable of accepting a variety of media including money orders, smart cards, and checks and may include separate units directed to accepting a particular type of media.

A controller 10 manages the operation of the system. The controller 10 directs the flow of documents from the input receptacle 16 through the transport mechanism 18, past the full image scanner 12 and the discrimination and authentication unit 14, and into the output receptacle 20. The transport mechanism directs the documents through the system such that the documents are scanned either along their wide dimension as shown in FIG. 1m. Alternatively, the documents are passed through the system such that they are scanned along their narrow dimension as shown in FIG. 1n. The controller 10 also directs the dispensing unit 22 to dispense funds to the user and routes information from the full image scanner 12 and the discrimination and authentication unit 14 to an interface 24 which communicates with an outside accounting system or central office. The controller is also capable of directing information from the outside office through the interface and to a communications panel 26. Finally, the controller 10 selectively processes information from the full image scanner 12 and the discrimination and authentication unit 14 for use by the system.

By "outside accounting system," it is meant to include the hardware and software associated with accessing, maintaining, tracking, and updating savings accounts, checking accounts, credit card accounts, business and commercial loans, consumer payments, and all other similar accounts at locations remotely located from the full image scanners. The term includes three broad types of systems: systems where deposits are made; systems where withdrawals are made; and systems where both deposits and withdrawals are made. Although the outside accounting system described herein is described as being employed at a financial institution such as a bank, it will be understood that any business, public or private institution, or individual can employ an outside accounting system to process transactions. By "financial institution" it is meant to include savings and loans, investment houses, and all other types of financial institutions whether private, public, or government. The following description is in terms of banks but it also includes all financial institutions as well.

Various types of payments are made between customers of a financial institution using a full image scanner and the accounting system at a selected financial institution. First, payments are made from one financial institution to another financial institution to settle accounts. Second, payments are made from a retail customer to a given financial institution or from the financial institution to the given retail customer. Third, financial institutions can issue payments to and receive payments from the Federal Reserve Banks within each region. Fourth, consumers can make payments or withdraw payments from financial institutions. Fifth, businesses of many kinds can make payments to or withdraw payments from financial institutions. The outside accounting system at the financial institution receives information which has been processed at the full image scanner of the present invention. The outside accounting system performs different operations based upon the type of media used in the transaction and the type of accounts accessed.

When checks are utilized in a transaction, the check is tagged with the customer checking account number, the bank number, and the Federal Reserve Region. If multiple banks are involved in the payment, each bank's number is tagged to the payment through an endorsement on the back of the check. Alternatively, the system could tag the checks electronically. In other words, the customer checking account number, bank number, and Federal Reserve region are electronically tagged to the check's image. Tagging also occurs on current electronic payments such as wire transfers.

The outside accounting system processes information associated with checking accounts which can be held by individual consumers, businesses, trade associations, trusts, non-profit organizations, or any other organization. Documents utilized in the check account function include checks, check account deposit slips, debit or credit slips which may be issued by the bank against the checking account, new account application forms, and forms for customers to reorder check and deposit slips. The full image scanner of the present invent processes all of these documents. The documents could be received at a full image scanner located at the teller line, a drive-up window, an ATM, or, alternatively, the documents may be received by mail. If received by mail, the bank employee immediately runs the documents through a full image scanner without having to forward the documents to a central location for processing. The outside accounting system maintains a record of all transactions regarding the checking account, balances, and tracks information associated with a particular check.

Savings accounts are another type of account for which the outside accounting system processes information. Savings accounts typically receive some rate of interest payment on the balances held. Individuals may maintain interest bearing savings accounts at a bank. Depending upon the terms, a savings account could vary in duration for withdrawal from immediate demand for withdrawal to as long as five years. When a consumer agrees to leave the funds for a longer period of time, this usually provides the account with a higher earning interest rate. Documents used in a savings account transaction include deposit slips, withdrawal slips, new account application slips and debit or credit slips which can be applied against the account by the given banking institution. The full image scanner of the present invention processes all of these documents. Again, the documents could be received at the teller line, drive-up window, ATM, or by mail, and immediately be scanned at point of entry without transporting the document to a central location. This information is sent to an outside accounting system where it can be stored, monitored, and analyzed. The accounting system compiles statistics on customers and their accounts and maintains current balances, interest earnings, available funds, available advances, and records all information concerning deposits and withdrawals.

Credit card accounts are another type of account that are handled by the outside accounting system. When a credit card is used in a transaction, the bank typically receives a commission The full image scanner of the present invention reads credit cards which are being used for electronic payment. The outside accounting system maintains a record of the customer's credit limit, available credit, current balance, and payment Preferably, the outside accounting system does not settle the credit card balance until the end of the month when the customer pays the balance due on the account.

The debit card is similar to a credit card but is a newer type of media. With the debit card, the customer's account is immediately debited when the transaction takes place. The full image processing system of the present invention accepts debit cards and performs the same functions described above with respect to credit cards.

Smart cards are a new evolving method of payment. Banks, phone companies, and transit authorities issue smart cards for use by customers. The smart cards have a pre-stored value in place which a customer draws against. Consumers might deposit cash or write a check or submit a savings withdrawal document through the full image scanner to purchase a smart card.

Various other types of documents are maintained by a bank. For example, a bank may maintain a trust for an individual such as a retirement trust account. An outside accounting system can maintain all types of information regarding these types of accounts such as account balances, interest earnings, and maturity dates.

The outside accounting system also maintains records and manages information concerning mortgages, consumer loans, and student loans. The outside accounting system maintains records such as the loan balance, last payment, interest rate, and amount paid.

The outside accounting system also distributes funds between the various accounts described above. For example, an individual, with checking and savings accounts at a bank, may also hold a mortgage with the bank. The outside accounting system can make monthly withdrawals from the checking account or savings account to pay the monthly mortgage amount due the bank. To accomplish this, the customer may issue a check for payment and submit this against a coupon provided to the customer by the bank with the required monthly mortgage payment. The coupon and the check (or savings withdrawal and coupon) are run through the full image scanner (at the teller line or automated teller). The information is read by the full image scanner and transmitted to the outside accounting system which conducts the required transfers.

A customer could use the outside accounting system to electronically remove any funds from an account without issuing a check as payment towards their mortgage. Alternately, a bank customer could mail the check payment and loan coupon to the bank. Upon receipt, the bank employee immediately runs the check and coupon through the full image scanner at any bank location--branch, central offices, payment center, etc. The document would not have to be forwarded to a centralized proof department for handling.

In a like manner, businesses can borrow funds from banks for mortgages on commercial property. Again, monthly payments are required, and the corporation must withdraw funds from their checking account to make these monthly payments. Again, an outside accounting system could be utilized to make an electronic payment without the use of checks by using wire transfer or other methods, or the check for payment and the coupon may be scanned by the full image scanner. Alternatively, a bank customer could mail the check payment and loan coupon to the bank. Upon receipt, the bank employee immediately runs the check and coupon though the scanner at any bank location--branch, central offices, payment center, etc. Thus, the document would not have to be forwarded to a centralized proof department for handling.

Consumer loan transactions, for example, involving auto loans, home improvement loans, and educational loans, is another type of transaction processed by the outside accounting system. Payments are typically made using the monthly repayment schedule by the issuing of the check payable to the bank for the monthly balance. Full image scanning of the check and loan coupon could be utilized for this transaction. The payment can be processed as described above. Alternatively, the customer could mail payment and the bank could process through its full image scanners.

Various types of business loan transactions are also processed by the outside accounting system including a "bank line of credit" or "revolving loan." This type of loan is typically one year in maturity. A given business draws up to an authorized amount in a given year. For example, a business may have a line of credit with a bank for up to $2 million, and, on a daily basis, draw on this line of credit. The typical collateral provided for this loan would include accounts receivables, inventory, etc. As long as the business has receivables to support the loan, it can draw up to as much as the authorized amount. Then, when the financial position of the business improves, the business pays down this revolving loan either by issuing a check payable to the bank or through wire electronic transfer from the business's cash account to the loan payment. The full image scanner could be used to accept such check payments and the outside accounting system at the bank processes these payments as described above.

Other types of loans, such as term loans which might have a five-year maturity with a scheduled principle repayment and interest payment required on a monthly or quarterly basis, are processed and tracked by the outside accounting system. Longer term loans, with collateral such as buildings, are also available that might have a 10 to 15 year life.

Banks sometimes underwrite bonds or other issues of securities by corporations. For example, a business may hold an industrial revenue bond issued by a city in the amount of $1.5 million. However, in support of the business's credit, the bank guarantees payment if the business could not perform. The business pays a small interest rate (for example, 1/4 or 1% per year) for the bank's guarantee. Checks are one method used by banks for such payments. Therefore, the full image scanner and outside accounting system may be utilized to process this type of transaction, as described above.

Another important service provided by the outside accounting system for business accounts is cash management. This can be provided by lock box services or sweep accounts. For example, a business needs a minimum operating cash balance in their checking account each day to meet requirements for payment to vendors or employees, for example. Each day, hundreds of payments from various customers of the business are received, typically by check. The checks are deposited into the general account of the business. When the business's account balances exceeds its operating requirements, the outside accounting system at the bank automatically "sweeps" extra funds from the non-interest bearing account to an interest bearing account such as commercial paper.

In a similar manner, many companies have customer payments directed to a bank "lock box." This lock box address is at a bank location and all customer payments to the company are diverted to this lock box address. This insures that the payments are deposited as quickly as possible so that the bank's commercial customers have immediate use of the funds at the bank. The next day the outside accounting system at the bank advises the business which payments were received into the account and the business adjusts its accounts receivables balance one day later, creating a timing problem due to the delay.

The full image scanner of the present invention enables a business to scan the documents through the scanner at the business's location (thus, eliminating the need to first send payments to a bank lock box location) and receive immediate credit electronically through the outside accounting system located at the bank. The check images and other images would immediately be available via the outside accounting system at the bank for settlement purposes. Therefore, lock box services by banks are handled on a de-centralized basis at bank customer locations.

Another service the outside accounting system provides is payment of payroll accounts. The business instructs the accounting system at the bank of the amounts to withdraw from the business's general account on the day of payroll and credit the employee payroll accounts. The outside accounting system can also provide direct deposits to employee accounts without actually issuing a check. Therefore, the employees have immediate use of their funds.

Businesses often maintain cash balances invested in bank commercial paper. The bank, via the accounting system, pays interest daily on the cash balances. Deposits and withdrawals are typically handled by a pre-authorized officer of the company such as the controller. Movement of funds typically require written authorization including a signature of the company officer. The full image scanner and outside accounting system of the present invention are utilized for withdrawals from commercial paper to a checking account or for purchase of commercial paper. This could be initiated by inserting a pre-designed form with an area to add the amount filed and authorized signature. The full image scanner captures the amount and seeks a match for the signature. The system, via the link with a central office computer 15, processes transactions substantially immediately. That is, deposits are processed in real time rather than waiting for the end of the day. Also, full images of all documents can be stored on mass storage devices 17 at the central office. The images could also be stored at the unit itself, or at another remote system. The images could also be temporarily stored and forwarded at a later time.

A personal computer 11 also be connected to the system. The personal computer can also process data from the scanning modules. Processing of scanned data can occur at the personal computer 11, within the full image scanning module 12 or the discrimination unit 14, or at the central office computer 15. The system also is connected to teller station 13 (which includes a video display).

Several full image scanners can be interconnected to form a local area network (LAN). The individual image scanners may be located at teller stations, in bank vaults, or at businesses, for example. In such a network, some or all image processing is accomplished at the image scanner and not at some centralized location. In other words, the processing functionality is "distributed" in such an arrangement. The individual LANs may have a different physical layouts or topologies. Referring now to FIG. 1w, full image scanners 6054, 6056, 6058, and 6060 are connected to common bus 6062. Bus 6062 is coupled to an interface 6052. The interface communicates with an outside accounting system which functions as described above. The bus-based network topology is inexpensive, reliable, and requires the least amount of cable for any LAN topology.

A LAN using a ring topology is illustrated in FIG. 1x. Full image scanners 6054, 6056, 6058, and 6060 retransmit information to adjacent scanners using point-to-point links. The scanners communicate with other networks through an interface 6052. Although more expensive than the bus topology, the ring topology lends itself to being able to transmit information over greater distances.

A LAN using a star topology is illustrated in FIG. 1y where a central full image scanner 6058 is connected to full image scanners 6054, 6056, 6060, and 6062. The central full image scanner communicates to other networks through an interface 6052. An advantage to the star topology is enhanced network management. Because all traffic passes the central full image scanner 6058, traffic monitoring is simple and detailed network reports are easy to produce. Enhanced security is inherently a part of this type of topology since the central unit can keep tables of user access rights as well as acceptable passwords. Also, the network can easily control who logs onto any remote device present on the network.

Referring now to FIG. 1u, there is illustrated another image processing network according to the present invention. An outside accounting system 6036 communicates with front end processor (FEP) 6038. The FEP 6038 is a software programmable controller that relieves the outside accounting system 6036 of many networking and data communications tasks. The FEP polls devices, performs error checking and recovery, character code translation, and dynamic buffer control. The FEP also serves as a data concentrator concentrating several low speed transmissions into a steady, high-speed flow of data. Full image scanners 6040, 6044, and 6046 communicate with the FEP 6038 (and the outside accounting system 6036) via cluster controller 6042. Cluster controller 6042 serves as an interface between the outside accounting system 6036 and the scanners 6040, 6044, and 6046. The image processing device 6036 has a master/slave relationship with the scanners 6040, 6044, and 6046 and polls, via FEP 6038, the devices and determines if they wish to communicate.

Another image processing network is described in connection with FIG. 1v. In this network, gateways are used to connect networks which have different network architectures. Gateways use all seven layers of the OSI model and perform protocol conversion functions at the Application layer. An outside accounting system 6148 is coupled to FEP 6150a which is connected to a token-ring interface coupler (TIC) gateway 6150b. TIC gateway 6150b provides connections to token ring networks 6156, 6162, and 6164 which include other full image scanners.

The highest performance LAN gateway is the link between a token-ring network 6156 and the image processing device's FEP 6150a via the TIC gateway 6150b. The TIC 6150b permits a 4 mbps or 16 mbps connection depending upon the hardware used. The TIC 6150b is viewed by the host as a cluster controller; the outside accounting system polls the TIC 6150b which in turn polls any units on the token-ring network 6156.

The network also contains a remote LAN gateway which functions as a gateway to another token ring LAN 6162. For example, the gateway 6161 functions as a cluster controller and communicates with the FEP using IBM's SDLC protocol via synchronous modems 6154 and 6155 at both sites. The synchronous modems 6154 and 6155 can dial up the FEP at speeds up to 64 kbps.

Remote X.25 LANs (which use the X.25 packet switching protocol and contain full image scanners) can also communicate with the host via X.25 gateways. A gateway 6151 with an adapter card functions as a cluster controller and runs special gateway 6151 software that runs over a given protocol and communicates with the X.25 network. A local coaxial gateway 6160 is also provided which allows a workstation on the LAN to emulate a distributed function terminal (DFT) mode of processing.

It should be realized that the units connected to particular gateways are in no way limited to use with a particular gateway. In fact, the gateways and units can be interchanged and other types of equipment can be used to structure the network as is known to those skilled in the art.

The communication panel 26 displays information to the user and accepts user commands. The panel 26 consists of a video screen 50 onto which information to the user is displayed by the system and a keyboard 52 for accepting commands from a user. As shown in FIG. 1c, the communications panel 26 can consist of a touch screen 27 or as shown in FIG. 1d, a combination of a touch screen 27 and keyboard 29. A slot 54 is used for receiving a user's identification card. The user inserts the card into the slot 54 to access the machine. The user deposits documents into bin 56. Loose currency is dispensed from slot 58, strapped currency from receptacle 60, and loose or rolled coin at receptacle 62.

As shown in FIG. 1p, other modules can be added to the system. A smart card acceptance module 63 is provided for accepting smart card. A smart card dispensing module 65 is provided for dispensing smart cards. An optical reader module 67 is also provided for accepting and dispensing optical media.

An audio microphone 64a and speaker 64b allow two-way communication between the user and a central office, for example, with a teller at a bank's central office. Thus, during the operating hours of a financial institution, bank personnel are connected to the system by the audio microphone 64a and speaker 64b. The central office computer 15 (which includes a video terminal) also receives and displays full video images of the documents from the system. If the documents are not recognizable, the image is forwarded to the bank employee for observation on the terminal. The bank employee could then discuss the document with the customer. In this case, the bank employee could decide to accept the document immediately for credit after reviewing the image on the terminal. With a full image scan, enough information may have been scanned on an unrecognizable document that review by the bank employee on the terminal will enable the bank employee to accurately call the value of the document. Additionally, the image of a document may be presented on a teller's monitor. By reviewing the data, the teller may be able to enter missing data via their keyboard, if the image is recognizable. If the teller is near the machine and an image on the monitor is unclear, the teller may remove the document from the scanner, inspect the document, and enter the missing data. The value could also be entered by the denomination keys and other information by a alphanumeric keypad, as described below, or with a mouse and applications software. Additionally, the value could be entered by a touch screen device or by any combination of the input means described above. The document would then be placed in back of the output receptacle 20 and processing would continue. In some situations, the customer might enter the value or other information concerning the unidentified documents. This entry would be via the keyboard and credit would be given to the customer's account only after the document is verified by bank personal. In other situations, the customer may merely hold onto the document.

A mentioned previously, the system has a slot for the insertion of a customer identification card. Alternatively, the customer might enter a PIN identification number through the keyboard. After identification of the customer is determined, then the customer submits a document (such as a check or savings account withdrawal slip) and immediate payment to the customer is made.

The output receptacle 20 can be a single bin as shown in FIG. 1a into which all documents transported by the transport mechanism 18 are stored. Alternatively, the output receptacle 20 can consist of dual bins as shown in FIG. 1e. In the case of dual bins, identifiable documents are placed into the first bin and unidentifiable documents are placed into the second bin. Additionally, as shown in FIG. 1f, any number of output bins can be used to store the documents. For example, currency of particular denominations can be stored in separate bins. For example, one bin each can be used to store $1, $5, $10, $20, $50, and $100 bills.

As shown in FIG. 1g, the full image scanner can be used without the discrimination unit with a single output receptacle. Alternatively, as shown in FIG. 1h, a full image scanner can be used in a system without a discrimination unit with two output bins or receptacles. Finally, as shown in FIG. 1i, the full image scanner can be used in a system without a discrimination unit in a system containing any number of output bins.

FIG. 1s depicts an exterior perspective view and FIG. 1t is a side view of a multi-pocket document processing system 5010 according to one embodiment of the present invention. According to one embodiment the document processing system 5010 is compact having a height (H) of about 171/2 inches, width (W) of about 131/2 inches, and a depth (D) of about 15 inches. The evaluation device 5010 may be rested upon a tabletop.

In FIGS. 1s and 1t, documents are fed, one by one, from a stack of documents placed in an input receptacle 5012 into a transport mechanism. The transport mechanism includes a transport plate or guide plate 240 for guiding documents to one of a plurality of output receptacles 5217a and 5217b. Before reaching the output receptacles 5217a, 5217b a document can be, for example, evaluated, analyzed, authenticated, discriminated, counted and/or otherwise processed by a full image scanning module. The results of the above process or processes may be used to determine to which output receptacle 5217a, 5217b a document is directed. In one embodiment, documents such as currency bills are transported, scanned, and identified at a rate in excess of 800 bills or documents per minute. In another embodiment, documents such as currency bills are transported, scanned, and identified at a rate in excess of 1000 bills or documents per minute. In the case of currency bills, the identification includes the determination of the denomination of each bill.

The input receptacle 5012 for receiving a stack of documents to be processed is formed by downwardly sloping and converging walls 205 and 206 (see FIG. 1t) formed by a pair of removable covers (not shown) which snap onto a frame. The converging wall 206 supports a removable hopper (not shown) that includes vertically disposed side walls (not shown). One embodiment of an input receptacle is described and illustrated in more detail in U.S. patent application Ser. No. 08/450,505, filed May 26, 1995, entitled "Method and Apparatus for Discriminating and Counting Documents", now issued as U.S. Pat. No. 5,687,963, which is incorporated by reference in its entirety. The document processing system 5010 in FIG. 1s has a touch panel display 5015 in one embodiment of the present invention which displays appropriate "functional" keys when appropriate. The touch panel display 5015 simplifies the operation of the multi-pocket document processing system 5010. Alternatively or additionally physical keys or buttons may be employed.

From the input receptacle 5012, the documents are moved in seriatim from a bottom of the stack along a curved guideway 211 (shown in FIG. 1t) which receives documents moving downwardly and rearwardly and changes the direction of travel to a forward direction. Although shown as being fed from the bottom, the documents can be fed from the top, front, or back of the stack. The type of feeding used could be friction feed, a vacuum feed, or any other method of feeding known to those skilled in the art. A stripping wheel mounted on a stripping wheel shaft 219 aids in feeding the documents to the curved guideway 211. The curvature of the guideway 211 corresponds substantially to the curved periphery of a drive roll 223 so as to form a narrow passageway for the bills along the rear side of the drive roll 233. An exit end of the curved guideway 211 directs the documents onto the transport plate 240 which carries the documents through an evaluation section and to one of the output receptacles 5217a, 5217b.

Stacking of the documents in one embodiment is accomplished by a pair of driven stacking wheels 5212a and 5213a for the first or upper output receptacle 5217a and by a pair of stacking wheels 5212b and 5213b for the second or bottom output receptacle 5217b. The stacker wheels 5212a,b and 5213a,b are supported for rotational movement about respective shafts 214a,b journalled on a rigid frame and driven by a motor (not shown). Flexible blades of the stacker wheels 5212a and 5213a deliver the documents onto a forward end of a stacker plate 214a. Similarly, the flexible blades of the stacker wheels 5212b and 5213b deliver the bills onto a forward end of a stacker plate 214b.

A diverter 260 directs the documents to either the first or second output receptacle 5217a, 5217b. When the diverter is in a lower position, documents are directed to the first output receptacle 5217a. When the diverter 260 is in an upper position, documents proceed in the direction of the second output receptacle 5217b.

FIGS. 1j-l depict multi-pocket document processing system 10, such as a currency discriminators, according to embodiments of the present invention. FIG. 1j depicts a three-pocket document processing system 10. FIG. 1k depicts a four-pocket document processing system 10FIG. 1l depicts a six-pocket document processing system 10.

The multi-pocket document processing systems 10 in FIGS. 1j-l have a transport mechanism which includes a transport plate or guide plate 240 for guiding currency documents to one of a plurality of output receptacles 217. The transport plate 240 according to one embodiment is substantially flat and linear without any protruding features. Before reaching the output receptacles 217, a document can be, for example, evaluated, analyzed, authenticated, discriminated, counted and/or otherwise processed.

The multi-pocket document processing systems 10 move the documents in seriatim from a bottom of the stack along the curved guideway 211 which receives documents moving downwardly and rearwardly and changes the direction of travel to a forward direction. Although shown as being fed from the bottom, the documents can be fed from the top, front, or back of the stack. An exit end of the curved guideway 211 directs the documents onto the transport plate 240 which carries the documents through an evaluation section and to one of the output receptacles 217. A plurality of diverters 260 direct the documents to the output receptacles 217. When the diverter 260 is in a lower position, documents are directed to the corresponding output receptacle 217. When the diverter 260 is in an upper position, documents proceed in the direction of the remaining output receptacles.

The multi-pocket document processing systems 10 of FIGS. 1j-l according to one embodiment includes passive rolls 260, 251 which are mounted on an underside of the transport plate 240 and are biased into counter-rotating contact with their corresponding driven upper rolls 223 and 241. Other embodiments include a plurality of follower plates which are substantially free from surface features and are substantially smooth like the transport plate 240. The follower plates 262 and 278 are positioned in spaced relation to transport plate 240 so as to define a currency pathway therebetween. In one embodiment, follower plates 262 and 278 have apertures only where necessary for accommodation of passive rolls 268270, 284, and 286.

The follower plate, such as follower plate 262, works in conjunction with the upper portion of the transport plate 240 to guide a bill from the passive roll 251 to a driven roll 264 and then to a driven roll 266. The passive rolls 268, 270 are biased by H-springs into counter-rotating contact with the corresponding drive rolls 264 and 266.

The general operation of the automated document processing system is illustrated in FIG. 2. The user conducts a transaction at step 10a. During the transaction step 10a, the user places documents into the input receptacle 16, the full image scanner 12 scans a full image of the documents, selected parts of the image are processed by the image scanner 12, the discrimination and authentication unit 14 authenticates the document, and the document is placed in the output receptacle 20. During the transaction step 10a, any interaction with personnel at a central office, for example, with a bank teller, occurs. As previously described, the system may also include a smart card processing module, modules which accept and read all forms of magnetic and optical media, and modules which dispense smart cards and all forms of optical and magnetic media.

An alarm condition may be generated during a transaction. At step 10b, the system determines whether an alarm condition is present. If the answer is affirmative, then at step 10c the system responds to the alarm condition. The response may be automatic or may require manual action by the user. If the response is automatic, the system preferably flashes a warning light, for example a 24 VAC external light driven by a relay. If the response required is manual, the user is required to perform some manual action and instructions of how to proceed may be displayed to the user on a user display screen, as described below. Alarm conditions occur when the user presses a help key; when a currency dispenser becomes empty; when more than a programmable predetermined amount of foreign currency is detected; upon a system error condition; and when a bin is full. If the answer to step 10b is negative or upon completion of step 10c, operation continues at step 10d.

After the alarm condition is tested or handled, the amount deposited in the transaction is stored at step 10d for later use. The values are preferably stored in a computer memory. Next, at step 10e, the user or machine distributes the deposited amount stored in step 10d. Step 10e is also described in greater detail below and can, for example, consist of receiving the deposited amount in the form of bills, allocating it to a savings account, or receiving part of the deposit back in bills and crediting the remainder to a bank savings account. At step 10f, the user is given the choice of conducting a new transaction. If the answer is affirmative, the system returns to step 10a which is described above. If the user answers in the negative, then the machine stops.

The full image scanner 12 is now described in detail. In accordance with the present invention, the image scanner may be of the type disclosed in U.S. Pat. No. 4,888,812 which is herein incorporated by reference in its entirety. As shown in FIG. 3, the front and back surfaces of the documents are scanned by scan heads 80 and 82 and the images processed into video image data by electronic circuitry. The scan heads 80 and 82 are preferably charge coupled scanner arrays and generate a sequence of analog signals representing light and dark images defining the image on the document. The scan heads 80 and 82 are arranged for simultaneously scanning both the front and back of the documents and are connected respectively to analog-to-digital converters 84 and 86 which convert the analog values into discrete binary gray scale values of, for example, 256 gray scale levels. The scan heads are capable of obtaining images of varying resolutions. The particular resolution chosen, which can be varied by the user, is selected based upon the type of document being scanned, as is known in the art.

The high resolution gray scale image data from the analog-to-digital converters 84 and 86 is directed to an image data preprocessor 88 in which the data may be enhanced and smoothed and which serves to locate the edges of successive documents and discard irrelevant data between documents. If the documents are slightly skewed, the image preprocessor 88 can also perform rotation on the image data to facilitate subsequent processing.

The image data is monitored for unacceptable image quality by image quality unit 90. For example, the image quality unit 90 and monitors the distribution of gray scale values in the image data and create a histogram. As is well known in the art, acceptable quality images have a distribution of gray scale values within certain prescribed limits. If the gray scale distribution of the histogram falls outside these limits, this is indicative of poor image quality and an error condition is generated.

The image data is transmitted from the quality unit 90 to the image processor 92. As is known in the art, the optical scanners can additionally scan specified fields on the faces of the document. For example, when processing checks, the scan head may search for the "$" symbol as a coordinate to the left of the numeric check amount field box. As is known in the art, a straight coordinate system or dimension system is used where known dimensions of the box are used to locate the field. Also, when scanning currency, the system searches for the serial numbers printed at defined locations which the image processor 92 can locate. The processor 92 can be programmed to locate fields for various types of currency and perform processing as follows. Based on scanning certain areas on the currency or document, the processor 92 first identifies the type of currency, for example, U.S. bank notes. Then, based on the outcome of the previous step, certain fields of interest are located, and the information stored for use by the system. The processor 92 may also compresses the image data, as is known in the art, in preparation for transmission to an outside location.

The amount of image data per document may vary depending upon the size and nature of the document and the efficiency of the data compression and reduction for that particular document. To insure that no data is lost in the event that the volume of image data may temporally exceed the transfer capacity of the high speed data channel, a prechannel buffer 94 interposed prior to the data channel, which is connected to the controller 10. The capacity of the pre-channel buffer 94 is continually monitored by the controller 10 so that appropriate action may be taken if the buffer becomes overloaded. The compressed video image data is received by the controller 10 over a high-speed data channel 96 and is initially routed to temporary storage. The image buffer is preferably of a size capable of storing the image data from at least several batches or runs of checks or similar documents. The controller 10 in the full image scanner performs the functions of analyzing the data. Alternatively, as discussed above, analysis of the data can occur at the central office computer 15 or at a personal computer 11 attached to the system.

The personal computer or alternate means may be used to create images of documents that are electronic images only, without scanning documents. For example, the EDGE system by Cummins-Allison corporation could be used. In such a system, computer software electronically creates an image of a document such as a check. A special printer (not shown) is connected to the system to print documents with special fields such as magnetic ink fields.

A plurality of document processing systems may be connected in a "hub and spokes" network architecture as is known in the art. In order to prevent congestion, the image buffer on each document processing system stores data until polled by the central office computer or outside accounting system. When polled, the data is uploaded to the central office computer or accounting system.

Other scanning modules and methods can be used in place or in addition to the particular one described above. These include CCD array systems, multi-cell arrays and other well-known scanning techniques. Examples of these techniques and devices are described in U.S. Pat. No. 5,023,782; U.S. Pat. No. 5,237,158; U.S. Pat. No. 5,187,750; and U.S. Pat. No. 4,205,780 all of which are incorporated by reference in their entirety. The scanning module can also be a color image scanner such as the type described in U.S. Pat. No. 5,335,292 which is incorporated by reference in its entirety.

The discrimination and authentication unit may contain a single or multiple head scanner. Before explaining such a multiple head scanner, the operation of a scanner having a single scanhead is first described. In particular, a currency discrimination system adapted to U.S. currency is described in connection with FIGS. 4a-4d. Subsequently, modifications to such a discrimination and authentication unit will be described in obtaining a currency discrimination and authentication unit in accordance with the present invention. Furthermore, while the embodiments of the discrimination and authentication unit described below entail the scanning of currency bills, the discrimination and authentication unit of the present invention is applicable to other documents as well. For example, the system of the present invention may be employed in conjunction with stock certificates, checks, bonds, and postage and food stamps, and all other financial institution documents.

Referring now to FIG. 4a, there is shown a functional block diagram illustrating a currency discriminating unit having a single scanhead. The unit 910 includes a bill accepting station 912 where stacks of currency bills that need to be identified and counted are positioned by the transport mechanism. Accepted bills are acted upon by a bill separating station 914 which functions to pick out or separate one bill at a time for being sequentially relayed by a bill transport mechanism 916, according to a precisely predetermined transport path, across scanhead 918 where the currency denomination of the bill is scanned and identified. Scanhead 918 is an optical scanhead that scans for characteristic information from a scanned bill 917 which is used to identify the denomination of the bill The scanned bill 917 is then transported to a bill stacking station 920 where bills so processed are stacked for subsequent removal.

The optical scanhead 918 of FIG. 4a comprises at least one light source 922 directing a beam of coherent light downwardly onto the bill transport path so as to illuminate a substantially rectangular light strip 924 upon a currency bill 917 positioned on the transport path below the scanhead 918. Light reflected off the illuminated strip 924 is sensed by a photodetector 926 positioned directly above the strip. The analog output of photodetector 926 is converted into a digital signal by means of an analog-to-digital (ADC) converter unit 928 whose output is fed as a digital input to a central processing unit (CPU) 930.

While scanhead 918 of FIG. 4a is an optical scanhead, it should be understood that it may be designed to detect a variety of characteristic information from currency bills. Additionally, the scanhead may employ a variety of detection means such as magnetic, optical, electrical conductivity, and capacitive sensors. Use of such sensors is discussed in more detail below, for example, in connection with FIG. 15.

Referring again to FIG. 4a, the bill transport path is defined in such a way that the transport mechanism 916 moves currency bills with the narrow dimension of the bills being parallel to the transport path and the scan direction. Alternatively, the system 910 may be designed to scan bills along their long dimension or along a skewed dimension. As a bill 917 moves on the transport path on the scanhead 918, the coherent light strip 924 effectively scans the bill across the narrow dimension of the bill. As depicted, the transport path is so arranged that a currency bill 917 is scanned by scanhead 918 approximately about the central section of the bill along its narrow dimension, as shown in FIG. 4a. The scanhead 918 functions to detect light reflected from the bill as it moves across the illuminated light strip 924 and to provide an analog representation of the variation in light so reflected which, in turn, represents the variation in the dark and light content of the printed pattern or indicia on the surface of the bill. This variation in light reflected from the narrow dimension scanning of the bills serves as a measure for distinguishing, with a high degree of confidence, among a plurality of currency denominations which the discrimination unit of this invention is programmed to handle.

A series of such detected reflectance signals are obtained across the narrow dimension of the bill, or across a selected segment thereof, and the resulting analog signals are digitized under control of the CPU 930 to yield a fixed number of digital reflectance data samples. The data samples are then subjected to a digitizing process which includes a normalizing routine for processing the sampled data for improved correlation and for smoothing out variations due to contrast fluctuations in the printed pattern existing on the bill surface. The normalized reflectance data so digitized represents a characteristic pattern that is fairly unique for a given bill denomination and provides sufficient distinguishing features among characteristic patterns for different currency denominations. This process is more fully explained in U.S. patent application Ser. No. 07/885,648, filed on May 19, 1992, now issued as U.S. Pat. No. 5,295,196 for a "Method and Apparatus for Currency Discrimination and Counting," which is incorporated herein by reference in its entirety.

In order to ensure strict correspondence between reflectance samples obtained by narrow dimension scanning of successive bills, the initiation of the reflectance sampling process is preferably controlled through the CPU 930 by means of an optical encoder 932 which is linked to the bill transport mechanism 916 and precisely tracks the physical movement of the bill 917 across the scanhead 918. More specifically, the optical encoder 932 is linked to the rotary motion of the drive motor which generates the movement imparted to the bill as it is relayed along the transport path. In addition, the mechanics of the feed mechanism (not shown, see U.S. Pat. No. 5,295,196 referred to above) ensure that positive contact is maintained between the bill and the transport path, particularly when the bill is being scanned by scanhead 918. Under these conditions, the optical encoder 932 is capable of precisely tracking the movement of the bill 917 relative to the light strip 924 generated by the scanhead 918 by monitoring the rotary motion of the drive motor.

The output of photodetector 926 is monitored by the CPU 930 to initially detect the presence of the bill underneath the scanhead 918 and, subsequently, to detect the starting point of the printed pattern on the bill, as represented by the thin borderline 917A which typically encloses the printed indicia on currency bills. Once the borderline 917A has been detected, the optical encoder 932 is used to control the timing and number of reflectance samples that are obtained from the output of the photodetector 926 as the bill 917 moves across the scanhead 918 and is scanned along its narrow dimension.

The use of the optical encoder 932 for controlling the sampling process relative to the physical movement of a bill 917 across the scanhead 918 is also advantageous in that the encoder 932 can be used to provide a predetermined delay following detection of the borderline prior to initiation of samples. The encoder delay can be adjusted in such a way that the bill 917 is scanned only across those segments along its narrow dimension which contain the most distinguishable printed indicia relative to the different currency denominations.

In the case of U.S. currency, for instance, it has been determined that the central, approximately two-inch (approximately 5 cm) portion of currency bills, as scanned across the central section of the narrow dimension of the bill, provides sufficient data for distinguishing among the various U.S. currency denominations on the basis of the correlation technique disclosed in U.S. Pat. No. 5,295,196 referred to above. Accordingly, the optical encoder can be used to control the scanning process so that reflectance samples are taken for a set period of time and only after a certain period of time has elapsed since the borderline 917A has been detected, thereby restricting the scanning to the desired central portion of the narrow dimension of the bill.

FIGS. 4b-4d illustrate the scanning process of scanhead 920 in more detail. Referring to FIG. 4b, as a bill 917 is advanced in a direction parallel to the narrow edges of the bill, scanning via a wide slit in the scanhead 918 is effected along a segment S of the central portion of the bill 917. This segment S begins a fixed distance D inboard of the borderline 917A. As the bill 917 traverses the scanhead 918, a strip s of the segment S is always illuminated, and the photodetector 926 produces a continuous output signal which is proportional to the intensity of the light reflected from the illuminated strip s at any given instant. This output is sampled at intervals controlled by the encoder, so that the sampling intervals are precisely synchronized with the movement of the bill across the scanhead 918.

As illustrated in FIGS. 4b and 4d, it is preferred that the sampling intervals be selected so that the strips s that are illuminated for successive samples overlap one another. The odd-numbered and even-numbered sample strips have been separated in FIGS. 4b and 4d to more clearly illustrate this overlap. For example, the first and second strips s1 and s2 overlap each other, the second and third strips s2 and s3 overlap each other, and so on. Each adjacent pair of strips overlap each other. For U.S. currency, this is accomplished by sampling strips that are 0.050 inch (0.127 cm) wide at 0.029 inch (0.074 cm) intervals, along a segment S that is 1.83 inch (4.65 cm) long (64 samples).

The optical sensing and correlation technique is based upon using the above process to generate a series of stored intensity signal patterns using genuine bills for each denomination of currency that is to be detected. According to one embodiment, two or four sets of master intensity signal samples are generated and stored within system memory, preferably in the form of an EPROM 934 (see FIG. 4a), for each detectable currency denomination. The sets of master intensity signal samples for each bill are generated from optical scans, performed on the green surface of the bill and taken along both the "forward" and "reverse" directions relative to the pattern printed on the bill. Alternatively, the optical scanning may be performed on the black side of U.S. currency bills or on either surface of bills from other countries. Additionally, the optical scanning may be performed on both sides of a bill, for example, by placing a scanhead on each side of the bill transport path as described in more detail in U.S. patent application Ser. No. 08/207,592 filed Mar. 8, 1994, for a "Method and Apparatus for Currency Discrimination," now issued as U.S. Pat. No. 5,467,406, and incorporated herein by reference.

In adapting this technique to U.S. currency, for example, sets of stored intensity signal samples are generated and stored for seven different denominations of U.S. currency, i.e., $1, $2, $5, $10, $20, $50 and $100. For bills which produce significant pattern changes when shifted slightly to the left or right, such as the $2 and the $10 bill in U.S. currency, it is preferred to store two patterns for each of the "forward" and "reverse" directions, each pair of patterns for the same direction represent two scan areas that are slightly displaced from each other along the long dimension of the bill. Accordingly, a set of a number of different master characteristic patterns is stored within the system memory for subsequent correlation purposes. Once the master patterns have been stored, the pattern generated by scanning a bill under test is compared by the CPU 930 with each of the master patterns of stored intensity signal samples to generate, for each comparison, a correlation number representing the extent of correlation, i.e., similarity between corresponding ones of the plurality of data samples, for the sets of data being compared. In the case of checks, the system compares the image signature to a stored master signature or to an account number.

The CPU 930 is programmed to identify the denomination of the scanned bill as corresponding to the set of stored intensity signal samples for which the correlation number resulting from pattern comparison is found to be the highest. In order to preclude the possibility of mischaracterizing the denomination of a scanned bill, as well as to reduce the possibility of spurious notes being identified as belonging to a valid denomination, a bi-level threshold of correlation is used as the basis for making a "positive" call. Such a method is disclosed in U.S. Pat. No. 5,295,196 referred to above. If a "positive" call can not be made for a scanned bill, an error signal is generated.

Using the above sensing and correlation approach, the CPU 930 is programmed to count the number of bills belonging to a particular currency denomination as part of a given set of bills that have been scanned for a given scan batch, and to determine the aggregate total of the currency amount represented by the bills scanned during a scan batch. The CPU 930 is also linked to an output unit 936 (FIG. 4a) which is adapted to provide a display of the number of bills counted, the breakdown of the bills in terms of currency denomination, and the aggregate total of the currency value represented by counted bills. The output unit 936 can also be adapted to provide a print-out of the displayed information in a desired format.

A procedure for scanning bills and generating characteristic patterns is described in U.S. Pat. No. 5,295,196 referred to above and incorporated by reference in its entirety and co-pending U.S. patent application Ser. No. 08/243,807, filed on May 16, 1994 and entitled "Method and Apparatus for Currency Discrimination", now issued as U.S. Pat. No. 5,633,949.

The optical sensing and correlation technique described in U.S. Pat. No. 5,295,196 permits identification of pre-programmed currency denominations with a high degree of accuracy and is based upon a relatively short processing time for digitizing sampled reflectance values and comparing them to the master characteristic patterns. The approach is used to scan currency bills, normalize the scanned data and generate master patterns in such a way that bill scans during operation have a direct correspondence between compared sample points in portions of the bills which possess the most distinguishable printed indicia. A relatively low number of reflectance samples is required in order to be able to adequately distinguish among several currency denominations.

Now that a single scanhead currency scanner has been described in connection with scanning U.S. currency, a currency discrimination unit according to an embodiment of the present invention will be described. In particular, a discrimination unit that can accommodate bills, checks, or any financial institution document of non-uniform size and/or color will be described.

First of all, because currencies come in a variety of sizes, sensors are added to determine the size of a bill to be scanned. These sensors are placed upstream of the scanheads to be described below. One embodiment of size determining sensors is illustrated in FIG. 4e. Two leading/trailing edge sensors 962 detect the leading and trailing edges of a bill 964 as it passing along the transport path. These sensors in conjunction with the encoder 932 (FIG. 4a) may be used to determine the dimension of the bill along a direction parallel to the scan direction which in FIG. 4e is the narrow dimension (or width) of the bill 964. Additionally, two side edge sensors 966 are used to detect the dimension of a bill 964 transverse to the scan direction which in FIG. 4e is the wide dimension (or length) of the bill 964. While the sensors 962 and 966 of FIG. 4e are optical sensors, any means of determining the size of a bill may be employed.

Once the size of a bill is determined, the potential identity of the bill is limited to those bills having the same size. Accordingly, the area to be scanned can be tailored to the area or areas best suited for identifying the denomination and country of origin of a bill having the measured dimensions.

Secondly, while the printed indicia on U.S. currency is enclosed within a thin borderline, the sensing of which may serve as a trigger to begin scanning using a wider slit, most currencies of other currency systems such as those from other countries do not have such a borderline. Thus the system described above may be modified to begin scanning relative to the edge of a bill for currencies lacking such a borderline. Referring to FIG. 4f, two leading edge detectors 968 are shown. The detection of the leading edge 69 of a bill 970 by leading edge sensors 968 triggers scanning in an area a given distance away from the leading edge of the bill 970, e.g., D.sub.1 or D.sub.2, which may vary depending upon the preliminary indication of the identity of a bill based on the dimensions of a bill. Alternatively, the leading edge 69 of a bill may be detected by one or more of the scanheads (to be described below). Alternatively, the beginning of scanning may be triggered by positional information provided by the encoder 932 of FIG. 4a, for example, in conjunction with the signals provided by sensors 962 of FIG. 4e, thus eliminating the need for leading edge sensors 968.

However, when the initiation of scanning is triggered by the detection of the leading edge of a bill, the chance that a scanned pattern will be offset relative to a corresponding master pattern increases. Offsets can result from the existence of manufacturing tolerances which permit the location of printed indicia of a document to vary relative to the edges of the document. For example, the printed indicia on U.S. bills may vary relative to the leading edge of a bill by as much as 50 mils which is 0.05 inches (1.27 mm). Thus when scanning is triggered relative to the edge of a bill (rather than the detection of a certain part of the printed indicia itself, such as the printed borderline of U.S. bills), a scanned pattern can be offset from a corresponding master pattern by one or more samples. Such offsets can lead to erroneous rejections of genuine bills due to poor correlation between scanned and master patterns. To compensate, overall scanned patterns and master patterns can be shifted relative to each other as illustrated in FIGS. 5a and 5b. More particularly, FIG. 5a illustrates a scanned pattern which is offset from a corresponding master pattern. FIG. 5b illustrates the same patterns after the scanned pattern is shifted relative to the master pattern, thereby increasing the correlation between the two patterns. Alternatively, instead of shifting either scanned patterns or master patterns, master patterns may be stored in memory corresponding to different offset amounts.

Thirdly, while it has been determined that the scanning of the central area on the green side of a U.S. bill (see segment S of FIG. 4c) provides sufficiently distinct patterns to enable discrimination among the plurality of U.S. denominations, the central area may not be suitable for bills originating in other countries. For example, for bills originating from Country 1, it may be determined that segment S.sub.1 (FIG. 4f) provides a more preferable area to be scanned, while segment S.sub.2 (FIG. 4f) is more preferable for bills originating from Country 2. Alternatively, in order to sufficiently discriminate among a given set of bills, it may be necessary to scan bills which are potentially from such set along more than one segment, e.g., scanning a single bill along both S.sub.1 and S.sub.2.

To accommodate scanning in areas other than the central portion of a bill, multiple scanheads may be positioned next to each other. One embodiment of such a multiple scanhead system is depicted in FIG. 6. Multiple scanheads 972a-c and 972d-f are positioned next to each other along a direction lateral to the direction of bill movement. Such a system permits a bill 74 to be scanned along different segments. Multiple scanheads 972a-f are arranged on each side of the transport path, thus permitting both sides of the bill 74 to be scanned.

Two-sided scanning may be used to permit bills to be fed into a currency discrimination unit according to the present invention with either side face up. An example of a two-sided scanhead arrangement is disclosed in U.S. patent application Ser. No. 08/207,592 filed on Mar. 8, 1994 and issued as U.S. Pat. No. 5,467,406 and incorporated herein by reference. Master patterns generated by scanning genuine bills may be stored for segments on one or both sides. In the case where master patterns are stored from the scanning of only one side of a genuine bill, the patterns retrieved by scanning both sides of a bill under test may be compared to a master set of single-sided master patterns. In such a case, a pattern retrieved from one side of a bill under test should match one of the stored master patterns, while a pattern retrieved from the other side of the bill under test should not match one of the master patterns. Alternatively, master patterns may be stored for both sides of genuine bills. In such a two-sided system, a pattern retrieved by scanning one side of a bill under test should match with one of the master patterns of one side (Match 1) and a pattern retrieved from scanning the opposite side of a bill under test should match the master pattern associated with the opposite side of a genuine bill identified by Match 1.

Alternatively, in situations where the face orientation of a bill (i.e., whether a bill is "face up" or "face down") may be determined prior to or during characteristic pattern scanning, the number of comparisons may be reduced by limiting comparisons to patterns corresponding to the same side of a bill. That is, for example, when it is known that a bill is "face up", scanned patterns associated with scanheads above the transport path need only be compared to master patterns generated by scanning the "face" of genuine bills. By "face" of a bill it is meant a side which is designated as the front surface of the bill. For example, the front or "face" of a U.S. bill may be designated as the "black" surface while the back of a U.S. bill may be designated as the "green" surface. The face orientation may be determinable in some situations by sensing the color of the surfaces of a bill. An alternative method of determining the face orientation of U.S. bills by detecting the borderline on each side of a bill is disclosed in U.S. Pat. No. 5,467,406. The implementation of color sensing is discussed in more detailed below.

According to the embodiment of FIG. 6, the bill transport mechanism operates in such a fashion that the central area C of a bill 74 is transported between central scanheads 972b and 972e. Scanheads 972a and 972c and likewise scanheads 972d and 972f are displaced the same distance from central scanheads 972b and 972e, respectively. By symmetrically arranging the scanheads about the central region of a bill, a bill may be scanned in either direction, e.g., top edge first (forward direction) or bottom edge first (reverse direction). As described above with respect to FIG. 4a, master patterns are stored from the scanning of genuine bills in both the forward and reverse directions. While a symmetrical arrangement is preferred, it is not essential provided appropriate master patterns are stored for non-symmetrical system.

While FIG. 6 illustrates a system having three scanheads per side, any number of scanheads per side may be utilized. Likewise, it is not necessary that there be a scanhead positioned over the central region of a bill. For example, FIG. 7 illustrates another embodiment of the present invention capable of scanning the segments S.sub.1 and S.sub.2 of FIG. 4f. Scanheads 976a, 976d, 976e, and 976h scan a bill 78 along segment S.sub.1 while scanheads 976b, 976c, 976f, and 976g scan segment S.sub.2.

FIG. 8 depicts another embodiment of a scanning system according to the present invention having laterally moveable scanheads 980a-b. Similar scanheads may be positioned on the opposite side of the transport path. Moveable scanheads 980a-b may provide more flexibility that may be desirable in certain scanning situations. Upon the determination of the dimensions of a bill as described in connection with FIG. 4e, a preliminary determination of the identity of a bill may be made. Based on this preliminary determination, the moveable scanheads 980a-b may be positioned over the area of the bill which is most appropriate for retrieving discrimination information. For example, if based on the size of a scanned bill, it is preliminarily determined that the bill is a Japanese 5000 Yen bill-type, and if it has been determined that a suitable characteristic pattern for a 5000 Yen bill-type is obtained by scanning a segment 2.0 cm to the left of center of the bill fed in the forward direction, scanheads 980a and 980b may be appropriately positioned for scanning such a segment, e.g., scanhead 980a positioned 2.0 cm left of center and scanhead 980b positioned 2.0 cm right of center. Such positioning permits proper discrimination regardless of the whether the scanned bill is being fed in the forward or reverse direction. Likewise scanheads on the opposite side of the transport path (not shown) could be appropriately positioned. Alternatively, a single moveable scanhead may be used on one or both sides of the transport path. In such a system, size and color information (to be described in more detail below) may be used to properly position a single laterally moveable scanhead, especially where the orientation of a bill may be determined before scanning.

FIG. 8, depicts a unit in which the transport mechanism is designed to deliver a bill 982 to be scanned centered within the area in which scanheads 980a-b are located. Accordingly, scanheads 980a-b are designed to move relative to the center of the transport path with scanhead 980a being moveable within the range R.sub.1 and scanhead 980b being moveable within range R.sub.2.

FIG. 9 depicts another embodiment of a scanning system according to the present invention wherein bills to be scanned are transported in a left justified manner along the transport path, that is wherein the left edge L of a bill 984 is positioned in the same lateral location relative to the transport path. Based on the dimensions of the bill, the position of the center of the bill may be determined and the scanheads 986a-b may in turn be positioned accordingly. As depicted in FIG. 9, scanhead 986a has a range of motion R.sub.3 and scanhead 986b has a range of motion R.sub.4. The ranges of motion of scanheads 986a-b may be influenced by the range of dimensions of bills which the discrimination unit is designed to accommodate. Similar scanheads may be positioned on the opposite side of the transport path.

Alternatively, the transport mechanism may be designed such that scanned bills are not necessarily centered or justified along the lateral dimension of the transport path. Rather the design of the transport mechanism may permit the position of bills to vary left and right within the lateral dimension of the transport path. In such a case, the edge sensors 966 of FIG. 4e may be used to locate the edges and center of a bill, and thus provide positional information in a moveable scanhead system and selection criteria in a stationary scanhead system.

In addition to the stationary scanhead and moveable scanhead systems described above, a hybrid system having both stationary and moveable scanheads may be used. Likewise, it should be noted that the laterally displaced scanheads described above need not lie along the same lateral axis. That is, the scanheads may be, for example, staggered upstream and downstream from each other. FIG. 10 is a top view of a staggered scanhead arrangement according to one embodiment of the present invention. As illustrated in FIG. 10, a bill 130 is transported in a centered manner along the transport path 132 so that the center 134 of the bill 130 is aligned with the center 136 of the transport path 132. Scanheads 140a-h are arranged in a staggered manner so as to permit scanning of the entire width of the transport path 132. The areas illuminated by each scanhead are illustrated by strips 142a, 142b, 142e, and 142f for scanheads 140a, 140b, 140e, and 140f, respectively. Based on size determination sensors, scanheads 140a and 140h may either not be activated or their output ignored.

In general, if prior to scanning a document, preliminary information about a document can be obtained, such as its size or color, appropriately positioned stationary scanheads may be activated or laterally moveable scanheads may be appropriately positioned provided the preliminary information provides some indication as to the potential identity of the document. Alternatively, especially in systems having scanheads positioned over a significant portion of the transport path, many or all of the scanheads of a system may be activated to scan a document. Then subsequently, after some preliminary determination as to a document's identity has been made, only the output or derivations thereof of appropriately located scanheads may be used to generate scanned patterns. Derivations of output signals include, for example, data samples stored in memory generated by sampling output signals. Under such an alternative embodiment, information enabling a preliminary determination as to a document's identity may be obtained by analyzing information either from sensors separate from the scanheads or from one or more of the scanheads themselves. An advantage of such preliminary determinations is that the number of scanned patterns which have to be generated or compared to a set of master patterns is reduced. Likewise the number of master patterns to which scanned patterns must be compared may also be reduced.

While the scanheads 140a-h of FIG. 10 are arranged in a non-overlapping manner, they may alternatively be arranged in an overlapping manner. By providing additional lateral positions, an overlapping scanhead arrangement may provide greater selectivity in the segments to be scanned. This increase in scanable segments may be beneficial in compensating for currency manufacturing tolerances which result in positional variances of the printed indicia on bills relative to their edges. Additionally, in one embodiment, scanheads positioned above the transport path are positioned upstream relative to their corresponding scanheads positioned below the transport path.

In addition to size and scanned characteristic patterns, color may also be used to discriminate bills. For example, while all U.S. bills are printed in the same colors, e.g., a green side and a black side, bills from other countries often vary in color with the denomination of the bill. For example, a German 50 deutsche mark bill-type is brown in color while a German 100 deutsche mark bill-type is blue in color. Alternatively, color detection may be used to determine the face orientation of a bill, such as where the color of each side of a bill varies. For example, color detection may be used to determine the face orientation of U.S. bills by detecting whether or not the "green" side of a U.S. bill is facing upwards. Separate color sensors may be added upstream of the scanheads described above. According to such an embodiment, color information may be used in addition to size information to preliminarily identify a bill. Likewise, color information may be used to determine the face orientation of a bill which determination may be used to select upper or lower scanheads for scanning a bill accordingly or compare scanned patterns retrieved from upper scanheads with a set of master patterns generated by scanning a corresponding face while the scanned patterns retrieved from the lower scanheads are compared with a set of master patterns generated by scanning an opposing face. Alternatively, color sensing may be incorporated into the scanheads described above. Such color sensing may be achieved by, for example, incorporating color filters, colored light sources, and/or dichroic beamsplitters into the currency discrimination unit of the present invention. Various color information acquisition techniques are described in U.S. Pat. Nos. 4,841,358; 4,658,289; 4,716,456; 4,825,246; and 4,992,860.

The operation of the currency discrimination unit according to one embodiment of the present invention may be further understood by referring to the flowchart of FIGS. 11a and 11b. In the process beginning at step 100, a bill is fed along a transport path (step 102) past sensors which measure the length and width of the bill (step 104). These size determining sensors may be, for example, those illustrated in FIG. 4e. Next at step 106, it is determined whether the measured dimensions of the bill match the dimensions of at least one bill stored in memory, such as EPROM 960 of FIG. 4e. If no match is found, an appropriate error is generated at step 108. If a match is found, the color of the bill is scanned for at step 110. At step 112, it is determined whether the color of the bill matches a color associated with a genuine bill having the dimensions measured at step 104. An error is generated at step 114 if no such match is found. However, if a match is found, a preliminary set of potentially matching bills is generated at step 116. Often, only one possible identity will exist for a bill having a given color and dimensions. However, the preliminary set of step 116 is not limited to the identification of a single bill-type, that is, a specific denomination of a specific currency system; but rather, the preliminary set may comprise a number of potential bill-types. For example, all U.S. bills have the same size and color. Therefore, the preliminary set generated by scanning a U S. $5 bill would include U.S. bills of all denominations.

Based on the preliminary set (step 116), selected scanheads in a stationary scanhead system may be activated (step 118). For example, if the preliminary identification indicates that a bill being scanned has the color and dimensions of a German 100 deutsche mark, the scanheads over regions associated with the scanning of an appropriate segment for a German 100 deutsche mark may be activated. Then upon detection of the leading edge of the bill by sensors 968 of FIG. 4f, the appropriate segment may be scanned. Alternatively, all scanheads may be active with only the scanning information from selected scanheads being processed. Alternatively, based on the preliminary identification of a bill (step 116), moveable scanheads may be appropriately positioned (step 118).

Subsequently, the bill is scanned for a characteristic pattern (step 120). At step 122, the scanned patterns produced by the scanheads are compared with the stored master patterns associated with genuine bills as dictated by the preliminary set. By only making comparisons with master patterns of bills within the preliminary set, processing time may be reduced. Thus for example, if the preliminary set indicated that the scanned bill could only possibly be a German 100 deutsche mark, then only the master pattern or patterns associated with a German 100 deutsche mark need be compared to the scanned patterns. If no match is found, an appropriate error is generated (step 124). If a scanned pattern does match an appropriate master pattern, the identity of the bill is accordingly indicated (step 126) and the process is ended (step 128).

While some of the embodiments discussed above entailed a unit capable of identifying a plurality of bill-types, the system may be adapted to identify a bill under test as either belonging to a specific bill-type or not. For example, the unit may be adapted to store master information associated with only a single bill-type such as a United Kingdom 5 .English Pound. bill. Such a system would identify bills under test which were United Kingdom 5 .English Pound. bills and would reject all other bill-types.

The scanheads of the present invention may be incorporated into the unit and used to identify a variety of documents including currency and financial institution documents such as checks, deposit slips, coupons and food stamps. For example, the unit may be designed to accommodate a number of currencies from different countries. Such a unit may be designed to permit operation in a number of modes. For example, the unit may be designed to permit an operator to select one or more of a plurality of bill-types which the system is designed to accommodate. Such a selection may be used to limit the number of master patterns with which scanned patterns are to be compared. Likewise, the operator may be permitted to select the manner in which bills will be fed, such as all bills face up, all bills top edge first, random face orientation, and/or random top edge orientation. Additionally, the unit may be designed to permit output information to be displayed in a variety of formats to a variety of peripherals, such as a monitor, LCD display, or printer. For example, the unit may be designed to count the number of each specific bill-types identified and to tabulate the total amount of currency counted for each of a plurality of currency systems. For example, a stack of bills could be placed in the bill accepting station 912 of FIG. 4a, and the output unit 936 of FIG. 4a may indicate that a total of 370 British pounds and 650 German marks were counted. Alternatively, the output from scanning the same batch of bills may provide more detailed information about the specific denominations counted, for example one 100 .English Pound. bill, five 50 .English Pound. bills, and one 20 .English Pound. bill and thirteen 50 deutsche mark bills.

FIG. 12 shows a block diagram of a counterfeit detector 210. A microprocessor 212 controls the overall operation of the counterfeit detector 210. It should be noted that the detailed construction of a mechanism to convey documents through the counterfeit detector 210 is not related to the practice of the present invention. Many configurations are well-known in the prior art. An exemplary configuration includes an arrangement of pulleys and rubber belts driven by a single motor. An encoder 214 may be used to provide input to the microprocessor 212 based on the position of a drive shaft 216, which operates the bill-conveying mechanism. The input from the encoder 214 allows the microprocessor to calculate the position of a document as it travels and to determine the timing of the operations of the counterfeit detector 210.

A stack of documents (not shown) may be deposited in a hopper 218 which holds the documents securely and allows the documents in the stack to be conveyed one at a time through the counterfeit detector 210. After the documents are conveyed to the interior of the counterfeit detector 210, a portion of the document is optically scanned by an optical sensor 220 of the type commonly known in the art. The optical sensor generates signals that correspond to the amount of light reflected by a small portion of the document. Signals from the optical sensor 220 are sent to an amplifier circuit 222, which, in turn, sends an output to an analog-to-digital converter 224. The output of the ADC is read by the microprocessor 212. The microprocessor 212 stores each element of data from the optical sensor 220 in a range of memory locations in a random access memory ("RAM") 226, forming a set of image data that corresponds to the object scanned.

As the document continues its travel through the counterfeit detector 210, it is passed adjacent to a magnetic sensor 228, which detects the presence of magnetic ink. The magnetic sensor 228 desirably makes a plurality of measurements along a path parallel to one edge of the document being examined. For example, the path sensed by the magnetic sensor 228 may be parallel to the shorter edges of the document and substantially through the document's center. The output signal from the magnetic sensor 228 is amplified by an amplifier circuit 230 and digitized by the ADC 224. The digital value of each data point measured by the magnetic sensor 228 is read by the microprocessor 212, whereupon it is stored in a range of memory in the RAM 226. The magnetic sensor 228 is capable of reading and identifying all types of magnetic ink. For instance, the sensor 228 can read "low dispersion" magnetic inks on checks. "Low dispersion" magnetic ink is magnetic ink mixed with color ink and used to print the background of checks as well as the name and address information on the check.

The digitized magnetic data may be mathematically manipulated to simplify its use. For example, the value of all data points may be summed to yield a checksum, which may be used for subsequent comparison to expected values computed from samples of genuine documents. As will be apparent, calculation of a checksum for later comparison eliminates the need to account for the orientation of the document with respect to the magnetic sensor 228. This is true because the checksum represents the concentration of magnetic ink across the entire path scanned by the magnetic sensor 228, regardless of variations caused by higher concentrations in certain regions of the document.

The image data stored in the RAM 226 is compared by the microprocessor 212 to standard image data stored in a read only memory ("ROM") 232. The stored image data corresponds to optical data generated from genuine documents such as currency of a plurality of denominations. The ROM image data may represent various orientations of genuine currency to account for the possibility of a document in the stack being in a reversed orientation compared to other documents in the stack. If the image data generated by the document being evaluated does not fall within an acceptable limit of any of the images stored in ROM, the document is determined to be of an unknown denomination. The machine stops to allow removal of the document from the stack of currency.

If the image data from the document being evaluated corresponds to one of the images stored in the ROM 232, the microprocessor 212 compares the checksum of the magnetic data to one of a plurality of expected checksum values stored in the ROM 232. An expected checksum value is stored for each denomination that is being counted. The value of each expected checksum is determined, for example, by averaging the magnetic data from a number of genuine samples of each denomination of interest. If the value of the measured checksum is within a predetermined range of the expected checksum, the document is considered to be genuine. If the checksum is not within the acceptable range, the operator is signaled that the document is suspect and the operation of the counterfeit detector 210 is stopped to allow its retrieval.

If the document passes both the optical evaluation and the magnetic evaluation, it exits the counterfeit detector 210 to a stacker 234. Furthermore, the counterfeit detector 210 may desirably include the capability to maintain a running total of genuine documents, for example, currency of each denomination.

It should be noted that the magnetic checksum is only compared to the expected checksum for a single denomination (i.e. the denomination that the optical data comparison has indicated). For instance, the only way in which a bill can be classified as genuine is if its magnetic checksum is within an acceptable range for its specific denomination. For a counterfeit bill to be considered genuine by the counterfeit detector of the present invention, it would have to be within an acceptable range in the denomination-discriminating optical comparison and have a distribution of magnetic ink within an acceptable range for its specific denomination.

To summarize the operation of the unit, a stack of documents, for example, bills or checks, is fed by the transport mechanism (element 18 in FIG. 1a) into the hopper 218. Each document is transported adjacent to the optical sensor 220, which generates image data corresponding to one side of the document. The document is also scanned by a magnetic sensor 228 and a plurality of data points corresponding to the presence of magnetic ink are recorded by the microprocessor 212. A checksum is generated by adding the total of all magnetic data points. The image data generated by the optical sensor 220 is compared to stored images, for example, images that correspond to a plurality of denominations of currency. When predetermined information such as the denomination of the bill being evaluated has been determined, the checksum is compared to a stored checksum corresponding to a genuine bill of that denomination. The microprocessor 212 generates a signal indicating that the document is genuine or counterfeit depending on whether said data is within a predetermined range of the expected value. Documents exit the counterfeit detector 210 and are accumulated in the stacker 234.

FIG. 13 is a flow diagram of an exemplary discrimination unit according to an embodiment of the present invention. At step 236, the presence of a bill approaching the optical sensor 220 is detected by the microprocessor 212, which initiates an optical scanning operation 238. Image data generated by the optical scanning operation are stored in RAM 226. The number of optical samples taken is not critical to the operation of the present invention, but the probability of accurate classification of the denomination of a bill increases as the number of samples increases.

At step 240, the microprocessor 212 initiates the magnetic scanning operation. The data points obtained by the magnetic scanning operation may be stored in the RAM 226 and added together later to yield a checksum, as shown in step 244. Alternatively, the checksum may be calculated by keeping a running total of the magnetic data values by adding each newly acquired value to the previous total. As with the optical scanning operation, the number of data points measured is not essential, but the chances of accurately identifying a counterfeit bill based on the concentration of magnetic ink improve as the number of samples increases. At step 242, the microprocessor determines the denomination of the bill by comparing the image data to a plurality of known images, each of which corresponds to a specific denomination of currency. The bill is identified as belonging to the denomination corresponding to one of the known scan patterns if the correlation between the two is within an acceptable range. At step 246, the checksum resulting from the summation of the magnetic data points is compared to an expected value for a genuine bill of the denomination identified by the comparison of the image data to the stored data.

The expected value may be determined in a variety of ways. One method is to empirically measure the concentration of magnetic ink on a sample of genuine bills and average the measured concentrations. Another method is to program the microprocessor to periodically update the expected value based on magnetic data measurements of bills evaluated by the counterfeit detector over a period of time.

If the checksum of the bill being evaluated is within a predetermined range of the expected value, the bill is considered to be genuine. Otherwise, the bill is considered to be counterfeit. As will be apparent, the choice of an acceptable variation from the expected checksum determines the sensitivity of the counterfeit detector. If the range chosen is too narrow, the possibility that a genuine bill will be classified as counterfeit is increased. On the other hand, the possibility that a counterfeit bill will be classified as genuine increases if the acceptable range is too broad.

FIG. 14 is a graphical representation of the magnetic data points generated by both a genuine pre-1996 series one hundred dollar bill (solid line) and a counterfeit one hundred dollar bill (broken line). As previously noted, bills are desirably scanned along a path that is parallel to one of their short edges. The graph shown in FIG. 14 shows magnetic data obtained by scanning a path passing approximately through the center of the bill. The measurements in the region designated "a" correspond to the area at the top of the bill. The area designated "b" corresponds to the central region of the bill and the region designated "c" corresponds to the bottom of the bill. The magnetic measurements for the genuine bill are relatively high in region a because of the high concentration of magnetic ink near the top of the bill. The concentration of magnetic ink in region b is relatively small and the concentration in region c is generally between the concentrations in regions a and c.

It should be noted that the concentration of magnetic ink in a typical counterfeit bill is uniformly low. Thus, the sum of the all data points for a counterfeit bill is generally significantly lower than for a genuine bill. Nonetheless, as counterfeiting techniques become more sophisticated, the correlation between genuine bills and counterfeits has improved.

The unit described above increases the chances of identifying a counterfeit bill because the denomination of a bill being evaluated is determined prior to the evaluation of the bill for genuineness. The checksum of the bill being evaluated is only compared to the expected checksum for a bill of that denomination. The process of identifying the denomination of the bill prior to evaluating it for genuineness minimizes the chance that a "good" counterfeit will generate a checksum indicative of a genuine bill of any denomination.

Referring next to FIG. 15, there is shown a functional block diagram illustrating one embodiment of a discrimination and authentication unit similar to that depicted in FIG. 4a but illustrating the presence of a second detector. The discrimination and authentication unit 250 includes a bill accepting station 252 where stacks of currency bills that need to be identified, authenticated, and counted are positioned. Accepted bills are acted upon by a bill separating station 254 which functions to pick out or separate one bill at a time for being sequentially relayed by a bill transport mechanism 256, according to a precisely predetermined transport path, across two scanheads 260 and 262 where the currency denomination of the bill is identified and the genuineness of the bill is authenticated. In the embodiment depicted, the scanhead 260 is an optical scanhead that scans for a first type of characteristic information from a scanned bill 257 which is used to identify the bill's denomination. The second scanhead 262 scans for a second type of characteristic information from the scanned bill 257. While in the illustrated embodiment scanheads 260 and 262 are separate and distinct, it is understood that these may be incorporated into a single scanhead. For example, where the first characteristic sensed is intensity of reflected light and the second characteristic sensed is color, a single optical scanhead having a plurality of detectors, one or more without filters and one or more with colored filters, may be employed (U.S. Pat. No. 4,992,860 incorporated herein by reference). The scanned bill is then transported to a bill stacking station 264 where bills so processed are stacked for subsequent removal.

The optical scanhead 260 of the embodiment depicted in FIG. 15 comprises at least one light source 266 directing a beam of coherent light downwardly onto the bill transport path so as to illuminate a substantially rectangular light strip 258 upon a currency bill 257 positioned on the transport path below the scanhead 260. Light reflected off the illuminated strip 258 is sensed by a photodetector 268 positioned directly above the strip. The analog output of the photodetector 268 is converted into a digital signal by means of an analog-to-digital (ADC) converter unit 270 whose output is fed as a digital input to a central processing unit (CPU) 272.

The second scanhead 262 comprises at least one detector 274 for sensing a second type of characteristic information from a bill. The analog output of the detector 274 is converted into a digital signal by means of a second analog to digital converter 276 whose output is also fed as a digital input to the central processing unit (CPU) 272.

While scanhead 260 in the embodiment of FIG. 15 is an optical scanhead, it should be understood that the first and second scanheads 260 and 262 may be designed to detect a variety of characteristic information from currency bills. Additionally these scanheads may employ a variety of detection means such as magnetic or optical sensors. For example, a variety of currency characteristics can be measured using magnetic sensing. These include detection of patterns of changes in magnetic flux (U.S. Pat. No. 3,280,974), patterns of vertical grid lines in the portrait area of bills (U.S. Pat. No. 3,870,629), the presence of a security thread (U.S. Pat. No. 5,151,607), total amount of magnetizable material of a bill (U.S. Pat. No. 4,617,458), patterns from sensing the strength of magnetic fields along a bill (U.S. Pat. No. 4,593,184), and other patterns and counts from scanning different portions of the bill such as the area in which the denomination is written out (U.S. Pat. No. 4,356,473).

With regard to optical sensing, a variety of currency characteristics can be measured such as detection of density (U.S. Pat. No. 4,381,447), color (U.S. Pat. Nos. 4,490,846; 3,496,370; 3,480,785), length and thickness (U.S. Pat. No. 4,255,651), the presence of a security thread (U.S. Pat. No. 5,151,607) and holes (U.S. Pat. No. 4,381,447), and other patterns of reflectance and transmission (U.S. Pat. Nos. 3,496,370; 3,679,314; 3,870,629; 4,179,685). Color detection techniques may employ color filters, colored lamps, and/or dichroic beamsplitters (U.S. Pat. Nos. 4,841,358; 4,658,289; 4,716,456; 4,825,246, 4,992,860 and EP 325,364). An optical sensing system using ultraviolet light is described in the assignee's co-pending U.S. patent application Ser. No. 08/317,349, filed Oct. 4, 1994, now issued as U.S. Pat. No. 5,640,463, and incorporated herein by reference, and described below.

In addition to magnetic and optical sensing, other techniques of detecting characteristic information of currency include electrical conductivity sensing, capacitive sensing (U.S. Pat. No. 5,122,754 [watermark, security thread]; U.S. Pat. No. 3,764,899 [thickness]; U.S. Pat. No. 3,815,021 [dielectric properties]; U.S. Pat. No. 5,151,607 [security thread]), and mechanical sensing (U S. Pat. No. 4,381,447 [limpness]; U.S. Pat. No. 4,255,651 [thickness]).

Referring again to FIG. 15, the bill transport path is defined in such a way that the transport mechanism 256 moves currency bills with the narrow dimension of the bills parallel to the transport path and the scan direction. Alternatively, the system 250 may be designed to scan bills along their long dimension or along a skewed dimension. As a bill 257 moves on the transport path on the scanhead 260, the coherent light strip 258 effectively scans the bill across the narrow dimension of the bill. In the embodiment depicted, the transport path is so arranged that a currency bill 257 is scanned by scanhead 260 approximately about the central section of the bill along its narrow dimension, as best shown in FIG. 15. The scanhead 260 functions to detect light reflected from the bill as it moves across the illuminated light strip 258 and to provide an analog representation of the variation in light so reflected which, in turn, represents the variation in the dark and light content of the printed pattern or indicia on the surface of the bill. This variation in light reflected from the narrow dimension scanning of the bills serves as a measure for distinguishing, with a high degree of confidence, among a plurality of currency denominations which the discrimination and authentication unit of this invention is programmed to handle.

A series of such detected reflectance signals are obtained across the narrow dimension of the bill, or across a selected segment thereof, and the resulting analog signals are digitized under control of the CPU 272 to yield a fixed number of digital reflectance data samples. The data samples are then subjected to a digitizing process which includes a normalizing routine for processing the sampled data for improved correlation and for smoothing out variations due to "contrast" fluctuations in the printed pattern existing on the bill surface. The normalized reflectance data so digitized represents a characteristic pattern that is fairly unique for a given bill denomination and provides sufficient distinguishing features between characteristic patterns for different currency denominations. This process is more fully explained in U.S. patent application Ser. No. 07/885,648, filed on May 19, 1992, now issued as U.S. Pat. No. 5,295,196 for "Method and Apparatus for Currency Discrimination and Counting," which is incorporated herein by reference in its entirety.

In order to ensure strict correspondence between reflectance samples obtained by narrow dimension scanning of successive bills, the initiation of the reflectance sampling process is preferably controlled through the CPU 272 by means of an optical encoder 278 which is linke