Abstract:
The signature comparison process associated with bank approval processes is automated using signature capture devices and a stored database of valid signatures. A signature is captured as part of a normal credit transaction, digitized and compared with entries in a database of known valid signatures. In an automated gas pump environment, the signature is captured, compared and approved before any gas is dispensed.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to the field of computerized credit approval, and, more particularly, to digital signature comparison techniques for ensuring that a card user is authorized. 
     2. Description of Related Art 
     When a credit card holder receives a new credit card, he is requested to sign the back of the card. The purpose of this visible signature is to permit a comparison to be made with the signature of a person who presents the card in payment for goods or services. If the signature on the credit card invoice matches that on the card, the presenter of the card is presumed to be authorized to use the card. A variety of other types of cards are treated similarly and will also be referred to as “credit cards” for convenience even though the descriptor “credit” may not be entirely accurate. 
     In some business establishments, such as a restaurant, when a customer signs a credit card receipt, the waiter will take the card and the receipt to a cashier who performs an independent comparison of the signature on the card with the signature on the receipt. 
     In other business establishments, a customer is requested to sign a blank piece of paper. The signed blank paper and the card are then taken to a cashier who runs the card through a card reader, and compares the card signature with the signature on the blank paper. If the two match, the authorized credit slip is taken back to the card holder for signature without further comparison. 
     The way in which credit cards are handled, as just described, presents two problems. The most serious problem is that signature comparison often does not occur. The second problem is that the user must wait while a signature comparison process is undertaken. 
     With the advent of automated fuel pumps, any pretense of signature comparison has been given up and no attempt is made whatever to ensure that the person presenting the card for gasoline is an authorized holder of the card. This presents a problem that losses are higher than would be expected if a presenter of card anticipated at least a nominal check of signature for authenticity. 
     There is thus a need for improving the signature comparison process to eliminate obviously unauthorized holders of credit cards and other authorizing cards. 
     SUMMARY OF THE INVENTION 
     The present invention provides apparatus, methods, systems and processes for capturing signatures and for comparing signatures with authorized exemplars to ensure that a card holder is authorized to use the card. This is accomplished by capturing in digitized form a signature of a customer presenting a credit card and by submitting that signature either to the credit card company who issued the card or to a signature service where an automatic comparison will be made of the similarities between the signature of the person presenting the card and an authorized holder of the card. 
     The invention relates to a system for comparison of a signature with an authorized signature. The system uses a portable device having a docking port and containing a signature pad for capturing an electronic replica of a signature. The portable device docks with a computer which has a docking port for receiving the portable device and which is configured for downloading the electronic replica from the portable device and for sending that replica to a central computer over a network for comparison with an authorized signature. 
     The invention also relates to a system for processing payment information having a signature. A plurality of merchant terminals are connected to a network, for obtaining approval of payment information. The payment information includes a payment card number and an electronic replica of a signature. A central computer is also connected to the network and has a database of electronic replicas of respective authorized signatures. The central computer is configured to compare an electronic replica of a signature with authorized signatures for the payment card number and to approve payment when replicas of signatures match by more than a threshold amount. Merchant terminals may include a gas pump equipped with a signature pad. 
     The invention is also directed to apparatus for processing payment information which includes a central computer having a database of signatures accessible by a card number for which a particular signature is authorized. The computer has a receiver for receiving an electronic replica of a signature and a card number, an access mechanism for retrieving one or more authorized signatures for a received card number, a signature comparator for comparing a received electronic replica of a signature with the one or more authorized signatures for a received card number, and a transmitter for authorizing payment when the signature comparator indicates that the received signature matches an authorized signature for the received card number. 
     The invention is also directed to terminal apparatus for processing payment information including a transmitter for sending an electronic replica of a signature and a card number to a central computer, a receiver for receiving payment information from the central computer, and a docking port for receiving an electronic replica of a signature from a portable device and for sending it to the transmitter. 
     The invention is also directed to vending apparatus for processing payment information including a signature pad for capturing an electronic replica of a signature, a card reader, a transmitter for sending an electronic replica of a signature from the signature pad and a card number from the reader to a central computer, and a receiver for receiving payment information from the central computer. 
     The invention is also directed to a method of comparing signatures. A signature is captured in electronic form and sent to a central computer with a card number. It is there compared with stored replicas of authorized signatures for the card number. The signature may be captured in electronic form on a portable device and then the portable device is docked with a merchant computer and downloading the signature to the merchant computer. 
     The invention is also directed to a method of processing payment information having a signature by storing a plurality of electronic replicas of authorized signatures, receiving payment information including a payment card number and an electronic replica of a signature, comparing an electronic replica of a signature with authorized signatures for the payment card number and approving payment when replicas of signatures match by more than a threshold amount. 
     The invention is also directed to a method of obtaining payment information for vending apparatus by providing a signature pad on the vending apparatus and capturing an electronic replica of a signature using that pad. The electronic replica and the card number are sent to a central computer, and payment information is received from the central computer. 
     The invention is also directed to computer program products, each including one or more memory media, and a computer program stored on the one or more memory media. The computer programs stored on the memory media implement the apparatus, systems and methods described above. The memory media may also include a database of authorized signatures stored thereon. 
     Still other objects and advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein only the preferred embodiment of the invention is shown and described, simply by way of illustration of the best mode contemplated of carrying out the invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the invention. Accordingly, the drawing and description are to be regarded as illustrative in nature, and not as restrictive. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     The objects, features and advantages of the system of the present invention will be apparent from the following description in which: 
     FIGS. 1A and 1B illustrates respective embodiments of a signature capture device. 
     FIG. 2 illustrates is a block diagram of the construction of a signature capture device. 
     FIG. 3 is a flow chart of how a signature is captured in a signature capture device and uploaded to a master station. 
     FIG. 4 is an exemplary hardware arrangement for carrying out the invention. 
     FIG. 5 is a diagram illustrating a credit card transaction and signature approval process. 
     FIG. 6 is a flowchart of a signal approval process. 
     FIG. 7 illustrates an application of the signature approval process at an automated gas pump. 
    
    
     NOTATIONS AND NOMENCLATURE 
     The detailed descriptions which follow may be presented in terms of program procedures executed on a computer or network of computers. These procedural descriptions and representations are the means used by those skilled in the art to most effectively convey the substance of their work to others skilled in the art. 
     A procedure is here, and generally, conceived to be a self-consistent sequence of steps leading to a desired result. These steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It proves convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like. It should be noted, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. 
     Further, the manipulations performed are often referred to in terms, such as adding or comparing, which are commonly associated with mental operations performed by a human operator. No such capability of a human operator is necessary, or desirable in most cases, in any of the operations described herein which form part of the present invention; the operations are machine operations. Useful machines for performing the operation of the present invention include general purpose digital computers or similar devices. 
     The present invention also relates to apparatus for performing these operations. This apparatus may be specially constructed for the required purpose or it may comprise a general purpose computer as selectively activated or reconfigured by a computer program stored in the computer. The procedures presented herein are not inherently related to a particular computer or other apparatus. Various general purpose machines may be used with programs written in accordance with the teachings herein, or it may prove more convenient to construct more specialized apparatus to perform the required method steps. The required structure for a variety of these machines will appear from the description given. 
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1A and 1B illustrate respective embodiments of a signature capture device. In FIG. 1A, a signature capture device  100 A includes a touch screen signature pad  110  on which a printed receipt  130  is overlaid for signature. When the customer signs at a point indicated by X on the drawing, the pressure from the signature results in capturing a bit map of the signature utilizing the touch screen signature pad  110  located below the printed receipt. The captured signature can then be uploaded through a docking connector  120  to a master station for processing. 
     Signature capture device  100 B is similar to  100 A discussed above except that in lieu of a printed receipt  130 , an itemized bill  150  is shown on a display screen  140 . The touch screen area  110  serves as a signature pad for capturing a bit map of a user&#39;s signature. In the approach shown in FIG. 1B, no actual writing occurs; however, as the user presses on the touch screen display, the location of the pressure points are detected and the pixels underneath the pressure points are illuminated, thus replicating the process by which a pencil writes on a paper. 
     FIG. 2 is a block diagram of the construction of the signature capture devices of FIGS. 1A and 1B. As shown in FIG. 2, CPU  270  controls the capture and storage of signatures and their display. It also controls the transfer of a captured signature over the docking interface  220  to a master station. The CPU has access to all other devices over bus  260 . Memory  250  stores programs and data which the CPU uses in carrying out its functions. Touch screen signature pad  210  is used as an input/output device and is connected to the bus over touch screen pad interface  209 . Display  240  is also connected to the bus over display interface  239 . Display  240  is optional and is utilized with the embodiment shown in FIG.  1 B. It is not required for the embodiment shown in FIG.  1 A. 
     In operation, a user signs his touch screen signature pad  210  or a receipt positioned on the pad and a copy of that signature is captured and stored in memory  250 . It is simultaneously displayed on the touch screen signature pad  210 . When the signature capture device is docked, the stored signature is transferred over docking interface  220  to a master station for processing as discussed more hereinafter. If a paper receipt is not utilized, display  240  will display the itemized bill for the user&#39;s signature. The user then signs using touch screen signature pad  210  as before. 
     FIG. 3 is a flow chart of how a signature is captured in a signature capture device and uploaded to a master station. The coordinates of points where pressure exceeds some threshold is detected on the touch screen surface ( 300 ) and the value of pixels is changed to a certain value (e.g. on or off) and stored at corresponding points such as in a display buffer and/or in memory. The display buffer thus effectively illuminates the pixels underneath the points at which pressure exceeds the threshold value, thus, tracing the image of the signature on the display screen in an analog to that which is done with a Magic Slate. When the device is docked ( 320 ), transfer of the stored signature occurs to the master station ( 330 ). 
     FIG. 4 is an exemplary hardware arrangement for carrying out the invention. FIG. 4 shows a plurality of cash registers  420  connected to a central processing unit  410  over a bus  400 . A typical cash register is equipped with a keyboard  422  and a display  423 . A card reader/writer  424  is used for reading credit cards and, in some embodiments, for writing smart card information. Printer  425  is utilized for generating paper receipts in the traditional manner. Control of a cash drawer is illustrated at  426  and all of these devices are interfaced to the computer bus over cash register interface  421 . 
     Read only memory  430  contains, typically, boot strap routines and a basic input/output (BIOS) system utilized to initialize CPU  410  at start up. RAM  440  represents the main memory utilized for processing data. Drive controller  450  interfaces one or more disk type drives such as CD ROM  451 , floppy disc drive  452  and hard discs  453 . The number and type of drives utilized with a particular system will vary depending upon user requirements. 
     A network interface  460  permits communications to be sent to and received from a network. Communications port  470  may be used as an alternate means of communication or as a supplemental means of communication. That is, communications port  470  may be utilized for a dial-up connection to one or more networks whereas network interface  460  is a dedicated interface to a particular network. 
     Programs for controlling the operation of the apparatus shown in FIG. 4 are typically stored on a disc drive and then loaded into RAM for execution during the start-up of the computer. 
     A signature capture device docking interface  280  permits docking of the signature capture device disclosed in conjunction with FIG.  1 A and FIG.  1 B. 
     FIG. 5 is a diagram illustrating a credit card and signature approval process. Vender  500  sends a copy of a signature captured using the signature capture device to an authorizing agency, such as a credit card company  510 . The credit card company maintains a signature data base  520  of authorized signatures organized by, for example, credit card number. A copy of a known valid signature is retrieved from the signature data base and compared with the signatures sent from the vendor using comparison software  530 . Comparison software can be either pattern matching or handwriting analysis software that is available in the art. The result of the comparison is a measure of the degree of similarity or, alternatively, a measure of the confidence that the two signatures were written by the same person. If the similarities are sufficiently high or if the confidence is sufficiently high, then one may conclude that the signature is from an authorized source and the credit card company can return an authorization to the vendor stating (1) that the credit card is valid and not indicated as stolen and (2) that the signature compares favorably with that known to be from an authorized user. 
     The signature data base  520  can be collected as part of the credit card application process by digitizing a signature on the application and can include the signatures of a number of authorized users for the credit card so the comparison with any one user&#39;s signature in a favorable way will result in authorization of the transaction. 
     FIG. 6 is a flow chart of a signature approval process. When the signature capture device shown in FIG. 1A or  1 B is docked in the master station ( 600 ) the digital representation of signature is downloaded from the capture device into the master station ( 610 ) from which it is sent to an authorizing agent, such as a credit card company, together with the account number (credit card number) for authorization ( 620 ). A copy of one or more known valid signatures for the account number is retrieved ( 630 ) and a comparison made between the received and known signatures to see if the degree of similarity is acceptable ( 640 ). If it is ( 640 -Y) the transaction is approved ( 650 ). If it is not, ( 640 -N) a transaction is affirmatively disapproved ( 660 ) and messages to that effect are sent to the vendor originating the query. 
     The invention is particularly useful in a context of automated gasoline pumps where, as discussed above, no signature comparison normally occurs. This can be remedied by including a touch screen signature capture device at the pump ( 700 ) and requesting that the person presenting the credit card to the pump for the purchase of gasoline sign the signature capture device ( 760 ). A digitized version of the signature can then be forwarded directly to the credit card company who could check both the credit card and the signature to ensure that the person presenting the card is an authorized holder. 
     There has thus been described techniques for ensuring signature comparison in ways which overcome the problems of the prior art. 
     In this disclosure, there is shown and described only the preferred embodiment of the invention, but, as aforementioned, it is to be understood that the invention is capable of use in various other combinations and environments and is capable of changes or modifications within the scope of the inventive concept as expressed herein.