MXPA02006344A

MXPA02006344A - Charge card purchase.

Info

Publication number: MXPA02006344A
Application number: MXPA02006344A
Authority: MX
Inventors: Petter Ericson
Original assignee: Anoto Ab
Priority date: 1999-12-23
Filing date: 2000-12-22
Publication date: 2002-12-13
Also published as: BR0016683A; EP1244956A1; WO2001048592A1; CA2393923A1; AU2568001A; RU2002119570A; CN1413322A; JP2003518689A; KR20020065596A; KR100784577B1

Abstract

An arrangement for handling charge card purchases has a digital pen (1; 1) which is arranged to record the signature of a charge card purchaser in digital form when the purchaser writes the signature on a physical charge card receipt (2; 40) using a pen point (17) arranged on the digital pen. The arrangement also has a signal processing means (16; 33) which is arranged to produce a digital charge card receipt, which corresponds to the physical charge card receipt, by storing the digital signature together with digital purchase information relating to the charge card purchase to which said physical charge card receipt relates. A charge card receipt and a method of handling charge card purchases are also disclosed.

Description

PURCHASES WITH PAYMENT CARD FIELD OF THE INVENTION The present invention relates to an arrangement for handling purchases with a payment card, a method for handling purchases with a payment card and a payment card voucher.

BACKGROUND OF THE INVENTION In order for a purchase to be made with a payment card, it is generally necessary for the buyer to present his payment card and confirm the purchase with his signature on a payment card receipt that contains information about the purchase, for example the cost of the purchase. and the payment card number. The payment card voucher can be a preprinted payment card voucher filled out by the seller with information about the purchase. Certain information, such as the payment card number, can be added by an impression that is made of the payment card itself using a special device. When the buyer has signed the payment card voucher, he receives a copy of the voucher, while the seller keeps the original. Subsequently the original is sent to the seller's bank, where the information of the payment card voucher it is entered into a computer and forms the basis for the transfer of money from the buyer's account to the seller's account. This handling of the vouchers of payment cards has the disadvantage that it is totally manual with all that this involves in terms of the risk of errors and time of the physical handling of the vouchers. The seller can, for example, get to write incorrect information on the voucher, and the bank can get to enter incorrect information in your computer system. Some vendors have a payment card reader connected to a cash register, which allows a certain simplification of the handling. When a buyer wishes to make a purchase with a payment card, the seller passes the payment card through the payment card reader that reads information from the payment card from the payment card and sends it to the cash register that prints a voucher of payment card that the buyer can sign. This considerably reduces the risk of errors associated with the issuance of vouchers. In some cases, the buyer keeps a copy of the signed receipt, and the seller retains the original. In other cases, the buyer signs a receipt that the seller retains, while the buyer receives another receipt that indicates that the purchase was made by payment card but does not have a copy of the buyer's signature. In both cases, information about the purchase with a payment card can be sent to the bank in digital form.

However, the seller or the bank still has to store the physical vouchers of the payment card as proof in case a buyer subsequently claims that he did not make a purchase that has been charged to his account. In an additional variant, the buyer confirms the purchase by indicating his PIN code on a keyboard. In this case, all the information of the payment card voucher is sent to the bank in digital form. However, security is not so much because it is easier to discover the PIN code that belongs to a payment card than to forge the owner's signature.

BRIEF DESCRIPTION OF THE INVENTION An object of the present invention is to completely or partially correct the problems described above. - This object is achieved by an arrangement according to claim 1, a method according to claim 18, and a payment card voucher according to claim 22. More specifically, according to a first aspect of the invention , a provision is provided to handle purchases with a payment card, which comprises a handheld device, preferably a digital pen, which is arranged to record the signature of a buyer with a payment card in digital form when the buyer places the signature on a card. physical voucher for a payment card using a compass drawing line arranged in the handheld device, and a signal processing means that is arranged to produce a digital payment card voucher, which corresponds to the physical voucher of a payment card, by storing the digital signature together with the digital information of the purchase related to the purchase with payment card to which said physical voucher of payment card refers. An advantage of this provision is that the buyer can confirm the purchase with his signature on a physical proof of payment card that he can keep, and even the seller himself does not have to spend time managing physical payment card vouchers. Instead, a digital payment card voucher is created, which contains the signature of the buyer and therefore fully corresponds to and replaces the physical voucher of the payment card. More particularly, the digital payment card voucher comprises all the information that is added by hand and / or by machine in the physical voucher of the payment card in relation to the purchase. A further advantage of the arrangement according to the invention is that it does not require any fundamental change to the existing infrastructure to handle payment card vouchers. The only change that the buyer will notice is that he must use a digital pen or other handheld device instead of an ordinary pen. For banks, the change is that it is no longer necessary to enter information from purchases with a payment card manually because the information is received in digital form. They no longer have to store physical vouchers for payment cards.

The seller is also prevented from handling physical vouchers for payment cards. The handheld device is preferably provided by the vendor and is designed to be used at the vendor's premises. The handheld device could also, however, belong to the user. The signal processing means may be integrated in the handheld device. You could understand a software program that is executed by a processor. It could also be done in hardware by means of an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). The signal processing means could also be performed partially or totally in a separate unit of the handheld device. The term "payment card" as used in the present application can be a credit card, a debit card or any other physical card or unit that can be used to make purchases and requires a signature from the owner as confirmation of the purchase. The purchase with a payment card can refer to a product or service. The arrangement according to the invention can be used favorably by sellers who previously handled payment card purchases in a completely manual way by means of preprinted physical vouchers of payment cards. In this case, the handheld device can be ordered to record additional information in digital form when the The purchaser writes the additional information using the handheld device in the physical voucher of the payment card, this additional information in digital form constitutes at least in part said digital information of the purchase stored by the signal processing unit. The handheld device can therefore be used to record all the information that is filled manually in a preprinted physical receipt of a payment card. If required, the signal processing means may supplement the information that is filled in manually with date and time, for example, the name of the vendor, the serial number of the payment card voucher, a unique pen identifier (ID). pen) or similar information. The handheld device can be of various types. For example, it may contain an acceleration sensor or gyrosensor that records the movement of the device when the buyer writes with it. In a favorable modality, however, the handheld device comprises an optical sensor for recording images of the physical surface of the payment card when the buyer writes about it with the handheld device. In this way, no moving parts or complicated sensors are required. The recording of what the buyer writes can be done by recording a plurality of images with partially overlapping contents and determining the relative position of these images as described in International patent application WO 99/60467, which is incorporated in the present invention by reference. However, the arrangement conveniently comprises means for identifying a position coding design in said images and for converting the position encoding design in each image into coordinates for the handheld device position in the physical voucher of payment card when He recorded the image. In this way, what the buyer writes in the physical voucher of the payment card can be stored in a memory in the form of a sequence of coordinates by means of the signal processing means. In this case, the payment card voucher is thus provided with an absolute position coding design that encodes the coordinates for a plurality of absolute positions on the payment card voucher so that what the buyer writes on the voucher of payment card can be recorded by continuous readings of the position coding design. The signature written on the payment card voucher is recorded in such a way that it can be reproduced graphically, for example, on a computer screen. Additionally, the sequence of coordinates that make up the signature also makes it possible to determine exactly where the signature was written on the payment card voucher. This feature makes the comparison of the digital payment card voucher with the original physical voucher of the payment card so secure as the traditional comparison of the copy of the customer's payment card voucher with the original physical voucher of the payment card. The means for identifying and converting the position coding design into coordinates can be achieved by means of an appropriate processor and software in the handheld device. Alternatively, the medium may be formed as a part of the signal processing means which in turn may be integrated with the handheld device or a physically separate means. In the latter case, the handheld device only records images that are sent and processed in the signal processing medium. In one embodiment, the arrangement comprises a reservation of preprinted physical payment card vouchers that are provided with a position coding design on at least part of its surface. These physical preprinted payment card vouchers can have the appearance exactly as conventional physical preprinted vouchers for payment cards, with the difference that they are provided with a position coding design at least in part of their surface, whose part is that part or those parts that are going to be filled by means of the digital pen. An additional difference is that a copy is not required, but only one proof is sufficient. These preprinted payment card receipts can be used in the same way as conventional preprinted payment card receipts except for the fact that the required purchase information is filled using a digital pen or other handheld device.

As an alternative to preprinted physical vouchers for payment cards, the provision can use payment card vouchers that are printed at the time of purchase. For this purpose, the signal processing means may be arranged to have a voucher printer print out said physical payment card voucher. The physical voucher of the printed payment card conveniently comprises information describing the purchase, such as price, details of the product or service purchased, and payment card number. The arrangement may comprise a stock of paper, for example sheets or reels, the total surface of which is provided with a position coding design, said sheets or reels being used to print said physical voucher of payment card. In this case, the paper is previously printed in this way with position coding designs, and only the purchase information is added. In a favorable embodiment, however, the signal processing means is arranged to cause said voucher printer to print a position coding design at least in part of said physical payment card voucher. The advantage of this mode is that ordinary paper of one color can be used to print the vouchers. The position coding design is printed at least on that part of the receipt where the buyer is going to place his signature. If the buyer or seller will fill in additional information, of course the design of Position coding is also printed where this information will be filled. Printing could also be done in two runs, one with the position coding design and one with the other information. The arrangement may be favorably connected to a payment card reader in order to receive a payment card number from the payment card reader, the payment card number constitutes part of said digital purchase information. The signal processing means can thus receive the payment card number and any other information stored in a payment card from the payment card reader and add this information to the digital payment card voucher. Alternatively, the payment card reader may be part of the provision. The connection can be wired or wireless. In a favorable mode, the arrangement is connected to a cash register in order to receive at least part of said digital information from the purchase therefrom. In this mode, all the purchase information except for the payment card number is obtained from the cash register and can then be printed on the payment card voucher. Alternatively, the cash register may be part of the arrangement itself. Also here the connection can be wired or wireless. The provision can conveniently be ordered to send the digital voucher of payment card to an external unit, for example a bank. In this way, all the handling of the payment card vouchers can be done automatically. The position coding design described above is favorably of the types described in international patent applications WO 00/73983, PCT / SE00 / 01895, PCT / SE00 / 01897 and PCT / SE00 / 01898, which are incorporated in the present invention. by reference. According to a second aspect, the present invention relates to a method for handling purchases by payment card, which comprises the steps of submitting a physical voucher of a payment card to a buyer, having the buyer place his signature on the voucher physical payment card by means of a handheld device, which digitally records the signature when it is being written, and produce a digital voucher for a payment card comprising the signature in digital form and digital information of the purchase. According to a third aspect, the present invention relates to a payment card voucher comprising at least one writing area that is for the signature of a buyer, the voucher of payment card is provided with a coding design of position that extends over at least said writing area and makes possible the digital recording of the signature. The advantages of the method and the voucher of payment card are evident from the analysis of the disposition. What has been said about what The latter also applies, when appropriate, to the payment card method and voucher.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described by means of modalities with reference to the accompanying drawings, in which: Figure 1 shows schematically a first embodiment of an arrangement according to the invention, Figure 2 shows schematically a second embodiment of a arrangement according to the invention, which is to print physical vouchers of payment card at the time of purchase, Figure 3 is a schematic view of an enlarged portion of a sheet of paper provided with a position coding design, the figure 4 schematically shows how symbols included in the position coding design can be composed, and Figure 5 is a schematic view of an example of 4x4 symbols that are used to encode a position.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES The arrangement shown in Figure 1 for the handling of payment card vouchers comprises a handheld device in the form of a digital pen 1 as well as a preprinted voucher of payment card 2. The digital pen 1 comprises a frame 11 which in general lines has the form of a pen. There is an opening 12 in the short side of the frame. The frame essentially houses an optical part, an electronic part and an energy source. The optical part comprises at least one IR light emitting diode 13 for illuminating the surface to be reproduced and a light-sensitive area sensor 14, such as a CCD or CMOS sensor, for recording a two-dimensional image. Optionally, the pen may also contain a lens system (not shown). The IR light is absorbed by the position coding design and makes it visible to the sensor in this way. The power source for the pen is obtained from a battery 15 mounted in a separate compartment in the frame. The electronic part contains a processor 16 with associated memory. The processor is programmed to perform the functions described above.

The digital pen 1 also comprises a compass 17 line, by means of which the user can make ordinary writings based on pigments that simultaneously digitally record the digital pen. The digital pen 1 also comprises buttons 18 by means of which the unit is operated and controlled. Finally, it also has a transceiver 19 for short-range wireless communications, for example by IR light or radio waves, with external units. The payment card voucher 2 is a pre-printed proof of payment card. It has a series of 20 writing areas. These are for different items of purchase information, such as payment card number, purchase and price details, that the seller fills manually. It also has a writing area 21 that is for the buyer's signature. A position coding design 5 is printed on the entire surface of the payment card voucher. This position coding design 5 has the property that if an arbitrary part of the design of a certain minimum size is recorded, its position in the Position coding design and therefore in the payment card voucher can be determined unambiguously. The position coding design 5 may be of the type described in the aforementioned document US Pat. No. 5,852,434, in which each position is encoded by a specific symbol.

However, the position coding design is favorably of the type described in the international applications described above, wherein each position is encoded by a plurality of symbols, and each symbol contributes to the coding of a plurality of positions. The position coding design is composed of a small number of symbol types. An example is described in PCT / SE00 / 01085, in which a larger point represents a "one" and a smaller point represents a "zero". Another example is described in PCT / SE00 / 01895, in which four different displacements of a point relative to a frame point encode four different values. This position coding design is described in more detail below. Figure 1 shows the position coding design which is composed of symbols in the form of a larger point 5a and a smaller point 5b. For the purpose of clarity, the design is displayed only on a small part of the payment card voucher and at the same time greatly increased. The position coding design in the payment card voucher may constitute a subset of a larger position coding design. The subset encodes coordinates of points within a specific area of coordinates, which is an area of the part of a larger imaginary coordinate area. The coordinate area more large corresponds to all points, whose coordinates the largest position coding design has the ability to encode. The subset in the payment card voucher may be dedicated to the seller, so that only that specific vendor has the right to use the subset. Other subsets of the larger position coding design can be dedicated for other vendors. Even additional subsets of the larger position coding design can be dedicated for applications other than payment card vouchers. Whether the subset in the digital payment card vouchers is dedicated to a particular vendor or your business, it is possible, analyzing the coordinates that represent a digital signature, establishing later that this digital signature comes from the digital voucher of payment card of this determined vendor. In addition, the exact position in which the signature was placed on the payment card voucher can be established. All the payment card vouchers of a certain seller can have the same position coding design. Alternatively, all vouchers from this vendor may have unique position coding designs that nevertheless belong to a defined defined subset of the larger position coding design.

If a unique identifier of a digital pen is included in the digital payment card voucher, it is also possible to establish subsequently by which specific digital pen the signature was placed. The arrangement shown in Figure 1 is used as follows. When a payment card purchase is to be made, the seller takes the pre-printed voucher for payment card 2 and fills out the payment card number of the buyer, what the purchase relates to and the total, etc., in the areas of writing 20 by means of the digital pen 1. As the seller is writing, the optical sensor 14 records continuous images of the surface of the payment card voucher and therefore of the position coding design 5 which is located within the field of sensor vision 14. Processor 16 is programmed to record an image at a time from sensor 14, identify symbols in the image, determine which two coordinates (coordinate pair) the symbol encodes and store these coordinates in its memory. The processor 16 is also programmed to analyze pairs of stored coordinates and converts them into a polygonal series which constitutes a description of how the pen has moved on the writing areas 20, 21 of the payment card voucher. When the seller has filled out the purchase information on the payment card voucher, the buyer must confirm the purchase with his signature in the writing area 21. The signature is also placed using the digital pen that records the signature in digital form as a sequence of coordinates. The buyer then receives the physical proof of payment card as proof of purchase. The processor 16 also has software that executes a signal processing means that generates a digital payment card voucher. Alternatively, the signal processing means can be achieved as a physically separate signal processing unit to which the digital pen is connected. The signal processing means compiles the purchase information written in the writing areas of the payment card voucher to form a digital voucher of payment card that also includes the signature of the buyer in digital form and optionally the ID of the pen . The information does not have to be filled in a specific order so that the signal processing means has the ability to identify which piece of information is which. Instead, the signal processing means may use the coordinates to identify in which writing areas the information is written. The signal processing means may also contain ICR (Intelligent Character Recognition) software that interprets handwritten characters and stores them in encoded character format, for example, ASCII format. The signal processing means may store a plurality of digital payment card vouchers. These can then be transferred to an external unit, for example a computer or a mobile telephone, by means of the transceiver 19 for storing in the premises of the seller and / or for remitting to the seller's bank. In the modality described above, the vendor provides the digital pen. It is also possible to make the purchase by means of a digital pen owned by the buyer. In this case, the digitally recorded signature and additional purchase information may be transmitted to a vendor's signal processing means for further processing and storage. The information can be transmitted online at the time of writing, or later, after being stored in the memory of the signal processing means, and transmitted when establishing a connection with the receiver, such as a bank. The arrangement shown in Figure 2 is somewhat more advanced than that of Figure 1 and can be used for fully automatic handling of purchases with payment card. It includes a digital pen 1 ', a cash register 30, a payment card reader 31, a voucher printer 32, and a signal processing unit 33. The digital pen 1 ', the cash register 30, the payment card reader 31 and the printer of vouchers 32 are all connected to the signal processing unit 33 by wire or wireless. The digital pen 1 'is elaborated and functions in the same way as the digital pen 1 in figure 1 with the exception that the medium Signal processing is executed, at least in part, as a separate unit. The cash register 30 is an ordinary cash register. When a user indicates that the entry of purchase information recorded in the cash register refers to a card purchase, the cash register sends this purchase information to the signal processing unit 33. The payment card reader is a conventional payment card reader. When a vendor passes a payment card through the reader, the reader reads information stored on the card and sends this information from the payment card to the signal processing unit. The information on the payment card includes at least the payment card number. The signal processing unit 33 comprises a processor that is programmed to perform the functions described later. When the signal processing unit receives purchase information about a payment card purchase from the cash register 30 and a payment card number from the payment card reader 31, it stores this information in a file and then gives instructions to the voucher printer 32 to print a physical voucher for the payment card 40. The voucher for the payment card is printed on unprinted paper. The payment card printer prints on the one hand the purchase information and the payment card number received and on the other hand part, a position coding design 5 that extends over a part of receipt 40 where the buyer will place his signature. The position coding design is of the same type as described above in relation to figure 1. The printing can be done in a print run with the design and the proof of payment card printed at the same time. Alternatively, the payment card voucher can be printed on a paper already provided with the design. Another alternative is to first print the design with an ink absorbing IR light and then print the proof of payment card on a second run with another ink that does not absorb IR light but absorbs light on the visible scale, or vice versa. In this way, the ink used to form the voucher does not interfere with the IR reading of the design. When the proof of payment card 40 has been printed, the buyer confirms the purchase by placing his signature in the desired place by means of the digital pen 1 '. The signature is recorded by the digital pen in the manner described in relation to Figure 1 as a sequence of coordinate pairs. The coordinate sequence is transferred from the digital pen 1 'to the signal processing unit 33 which stores the coordinate sequence in the aforementioned file together with the card number and the purchase information. Optionally, a unique pen identity number (identifier) is transferred from the digital pen and stored in the file. This unique identity number can be used to subsequently verify which pen was used to sign the receipt of payment card. The Information items stored in the file together form a digital voucher for a payment card. When the buyer has signed the physical voucher for the payment card, he can keep it. The digital payment card voucher is sent directly or at a later time to the vendor's bank, where the information is processed in the same way as in a conventional payment card system. Preferably, the digital payment card voucher is also stored by the vendor. Two embodiments of an arrangement according to the invention and two variants of payment card vouchers have been described above. Other payment card provisions and vouchers are possible within the scope of the claims. For example, the arrangement does not have to comprise all the units described in Figure 2; the digital pen and the signal processing medium are sufficient. One or more of the other units may be added in Figure 2 below. The units shown in figure 2 do not have to be physically separate units either, but two or more of them can be integrated with each other. In the mode of Figure 2 the digital pen is provided by the vendor. It would also be possible to use a provision where the buyer provides the digital pen. In this case, the buyer's digital pen could communicate with the signal processing unit 33 to transfer the signature and any additional purchase information in digital form from the digital pen to the signal processing unit.

The natural behavior when writing a payment card voucher is to fill out all the details and / or verify all the voucher details and when everything is in order, the voucher is signed and can not be altered anymore. This behavior can also be used in the present situation. Thus, first all the strokes of the pen in the receipt are recorded and stored in a memory and stamped in time. When the voucher is finally signed, the pen waits for a few seconds and then compiles all the strokes of the voucher pen into a file, which closes now and can not be changed any more, like the situation with the physical voucher. Additionally, the termination of a signature is a signal to the pen to send the information to the receiver, by connecting to a network in order to transmit the file, for example, to the bank as described above. The termination of the signature can be indicated and a sending action initiated when there are no more strokes of the pen in the signature area within a few seconds, such as two seconds. Another alternative to indicate that a second action should be assumed, when the buyer's pen is used, is as follows. When there are no longer beats of the pen in the signature area within a certain time, such as three seconds, a signature verification software on the pen determines whether the signature can be verified to be the signature of the pen owner. When the determination is positive, the aforementioned file is compiled and closed and a sending action is initiated. Other combinations of these procedures are possible, such as that the file is compiled and closed to the verification of the signature but the sending action is initiated in other ways, such as pressing a button or marking a shipping box. When a single design is used for each separate voucher, the identity between the physical voucher and the voucher can be verified at any time after signing the voucher, in case there is any dispute as to whether the bank or the buyer has taken Do your homework Any manipulation with the physical or digital voucher will be easily discovered, since since then the two copies no longer coincide with each other. As already mentioned, the digital payment card vouchers are sent by the signal processing means to the corresponding bank or receiver. The digital payment card vouchers can also be registered by the signal processing means, so that the seller can later prove that the vouchers were sent to the bank. Alternatively or as a supplement, the bank may return a copy of the digital payment card voucher as an acknowledgment of the delivery of the voucher. In the modalities described above, the digital recording of the signature is carried out by means of a position coding design. As mentioned in the introduction, the recording can also be carried out by means of some form of sensor in the pen, which detects the movement of the pen. In this case, of course, totally ordinary physical payment card receipts can be used.

Finally, the preferred embodiment of the absolute position coding design will now be described. For the purpose of simplicity it is described in relation to sheets of paper. Corresponds to the absolute position coding design described in PCT / SE00 / 01895. It is referred to as a position coding design since a surface to which the position code is applied gives a slightly design impression. Figure 3 shows an enlarged portion of a sheet in which its surface 102 is provided with the position coding design 105. The sheet has a coordinate axis x and a coordinate axis y. The position encoding design comprises a virtual frame that is not visible to the human eye nor can be detected directly by a device that will determine positions on the surface, and a plurality of symbols, each of which may assume one of four values "1" - "4" as will be described later. The position coding design is arranged in such a way that the symbols on a partial surface of the paper sheet encode absolute coordinates of a point on an imaginary surface, which will be described later. A first and a second partial surface 125a, 125b are indicated by dashed lines in Figure 3. That part of the position coding design (in this case 4x4 symbols) to be found on the first partial surface 125a encodes the coordinates of a first point, and that part of the position coding design that is to be found in the second partial surface 125b encodes the coordinates of a second point on the imaginary surface. Thus, the position coding design is partially shared by the first and second contiguous points. Said position coding design is referred to in this application as "floating". Figures 4a-4d show a modality of a symbol that can be used in the position coding design. The symbol comprises a virtual frame point 130 which is represented by the intersection between the frame lines, and a mark 106 which has the shape of a point. The value of the symbol depends on where the brand is located. In the example in Figure 4, there are four possible locations, one in each of the raster lines that extend from the raster points. The offset from the raster point is equal to all values. In the following, the symbol in figure 4a has the value 1, in figure 4b the value 2, in figure 4c the value of 3 and in figure 4d the value 4. Expressed in other words, there are four different types of symbols. It should be noted that, of course, the points may have a different form. Each symbol can thus represent four values "1-4". This means that the position coding design can be divided into a first position code for the x coordinate, and a second position code for the y coordinate. The division is made as follows: In this way, the value of each symbol is translated into a first digit, in this case bit, for the code x and a second digit, in this case bit, for the code y. In this way, two completely independent bit designs are obtained. The designs can be combined to a design together, which is encoded graphically by means of a plurality of symbols according to Figure 4. The coordinates for each point are encoded by means of a plurality of symbols. In this example, 4x4 symbols are used to encode a position in two dimensions, that is, an x coordinate and a y coordinate. The position code is composed of a number series of ones and zeros that have the characteristic that no four-bit sequence appears more than once in the series. The numerical series is cyclical, which means that the characteristic also applies when one connects the end of the series at the beginning of the series. Thus, a sequence of four bits always has a determined position without ambiguity in the numerical series.

The series can be a maximum of 16 bits long if it is going to have the characteristics described above for four-bit sequences. In this example, however, use is made of a series that has a length of seven bits only as follows: "0 0 0 1 0 1 0". The series contains seven unique four-bit sequences that encode a position in the series as follows: To encode the x coordinate, the numeric series is written consecutively in columns across the entire surface to be encoded. The coding is based on the difference or displacement of position between numbers in contiguous columns. The size of the difference is determined by the position (that is, with what sequence) in the numerical series, in which one allows the column to start. More specifically, if one takes the seven module of difference between, on the one hand, a number that is coded by a sequence of four bits in a first column and that can thus have the value (position) 0-6 and, on the other hand , the corresponding number (that is, the sequence in the same "level") in a column contiguous, the result will be the same regardless of where one makes the comparison along two columns. By means of the difference between two columns, it is thus possible to encode a coordinate x that is constant for all the y coordinates. Since each position on the surface is encoded with 4x4 symbols in this example, three differences (which have the value 0-6) are available as indicated above for encoding the x coordinate. Then the coding is done in such a way that of the three differences, one will always have the value 1 or 2 and the other two will have values in the scale 3-6. Consequently, no difference is allowed to be zero in the code x. In other words, the code x is structured so that the differences are as follows: (3-6) (3-6) (1-2) (3-6) (3-6) (1-2) (3- 6) (3-6) (1-2) ... Each x coordinate is therefore coded with two numbers between 3 and 6 and a subsequent number that is 1 or 2. If three of the tall numbers and one is subtracted of the basses, a mixed base number will be obtained, which will directly provide a position in the x direction, from which the x coordinate can be determined directly, as shown in the following example. By means of the principle described above, it is thus possible to code coordinates x 0,1, 2 ..., with the help of numbers representing three differences. These differences are encoded with a bit design that is based on the previous numerical series. Finally, the bit design can be encoded graphically by means of the symbols in figure 4.

In many cases, when reading 4x4 symbols, it will not be possible to produce a complete number that encodes the x coordinate, but parts of two numbers. Since the least important part of the numbers is always 1 or 2, however, a complete number can easily be reconstructed. The y coordinates are coded according to the same principle that was used for the x coordinates. The cyclic number series is written repeatedly in horizontal rows along the surface to be encoded in position. As in the case of the x-coordinates, the rows are allowed to start in different positions, that is, with different sequences, in the numerical series. However, for the coordinates and one does not use differences but encodes the coordinates with numbers that are based on the starting position of the numerical series in each row. When the x coordinate for 4x4 symbols has been determined, in fact it is possible to determine the starting positions in the numerical series for the rows that are included in the code and in the 4x4 symbols. In the code and the most important digit is determined by allowing it to be the only one that has a value on a specific scale. In this example, one allows a row of four to start at position 0-1 in the number series to indicate that this row refers to the least important digit in one y coordinate, and the other three start in position 2-6. In the y direction, there is a series of numbers as follows: (2-6) (2-6) (2-6) (0-1) (2-6) (2-6) (2-6) (0 -1) (2.6) ... Each y coordinate is thus coded with three numbers between 2 and 6 and a subsequent number between 0 and 1.

If O is subtracted from the low number and 2 from the high, one obtains in the same way with respect to the direction x a position in the direction and in a mixed base from which it is possible to directly determine the y coordinate. With the above method it is possible to code 4 x 4 x 2 = 32 positions in the x direction. Each said position corresponds to three differences, which gives 3 x 32 = 96 positions. In addition, it is possible to code 5 x 5 x 5 x 2 = 250 positions in the y direction. Each said position corresponds to 4 rows, which gives 4 x 250 = 1000 positions. In general, it is possible to code 96000 positions in this way. Since the x coding is based on differences, however, it is possible to select in which position the first number series starts. If one takes into consideration that this first number series can start in seven different positions, it is possible to code 7 x 96000 = 672000 positions. The start position of the first number series in the first column can be calculated when the x coordinate has been determined. The seven different starting positions mentioned above for the first series can encode different sheets of paper or writing surfaces in a product. With the idea of further illustrating the function of a position coding design, a specific example follows which is based on the described mode of the position code. Figure 5 shows an example of an image with 4x4 symbols that are read by a device for position determination. These 4x4 symbols have the following values: 4442 3234 4424 1324 These values represent the following binary code xyy: Code x: Code y: 0000 0001 1010 0100 0000 0010 1100 1010 The vertical x sequences encode the following positions in the number series: 2046. The differences between the columns will be -242 , whose module 7 gives: 542, which in mixed base codes position (5-3) x 8 + (4-3) x 2 + (2-1) = 16 + 2 + 1 = 19. Since the first coded position x is position 0, the difference that is in the scale 1-2 and that will be seen in the 4x4 symbols is the twentieth said difference. Since there is a total of three columns for each difference and there is a start column, the vertical sequence farthest to the right in the x 4x4 code belongs to column 61 in the x code (3 x 20 + 1 = 61 ) and furthest to the left belongs to 58. Sequences and horizontals code positions 0413 in the number series. Since these series start in column 58, the starting position of the rows are these numbers minus 57 module 7, which produces the starting positions 6 3 0 2. Translated into digits in the mixed base, this will be 6-2, 3-2, 0-0, 2-4 = 4 1 0 0 where the third digit is the least important digit in the number in question. The fourth digit is then the most important digit in the next number. In this case, it must be the same as in the number in question. (An exceptional case is when the number in question consists of the highest possible digits in all positions.) Then one knows that the beginning of the next number is one greater than the beginning of the number in question.) The position of the four-digit number will then be in the mixed base 0x50 + 4x10 +1 x2 + 0x1 = 42. The third row in the code and is thus the 43 that has the starting position 0 or 1, and since there are four rows in everything in each said row, the third row is the number 43x4 = 172. Thus, in this example, the position of the highest left corner for the group of 4x4 symbols is (58,170). Since the x sequences in the 4x4 group start in row 170, the x columns of the entire design start at the positions of the number series ((2 0 4 6) - 169) module 7 = 1 6 3 5. Enter the last start position (5) and the first start position, numbers 0-19 are coded in the mixed base, and when adding the representations of numbers 0-19 in the mixed base, one gets the total difference between these columns . A simplistic algorithm to do this is to generate these twenty numbers and directly add your digits The resulting sum is called s. In this way the sheet of paper or writing surface will be given by the module 7 (5-s). In the previous example, a modality has been described, in which each position is encoded with 4x4 symbols and a numerical series with 7 bits is used. Of course, this is just an example. The positions can be coded with a greater or lesser number of symbols. The number of symbols does not need to be the same in both directions. The numerical series can be of different length and does not need to be binary, but can be established in another base. Different numerical series can be used to encode in the x direction and encode in the y direction. The symbols can have different numbers of values. As is evident from the above, an encoding with 6x6 symbols is preferred at this time, each symbol has the capacity to assume four values. One skilled in the art can easily generalize the above examples to involve such coding. In the previous example, the brand is a point but of course it can have a different appearance. For example, it may consist of a diagonal or some other indication that starts at the virtual screen point and extends from there to a predetermined position. As another alternative, the brand can consist of a rectangle, a square, a triangle or some other convenient figure, easily detected. The brand can be full or open.

In the previous example, symbols within a square partial surface are used to encode a position. The partial surface may have a different shape, such as hexagonal. The symbols do not need to be arranged in rows and columns at an angle of 90 ° to one another but can also be arranged in other angles, for example, 60 °, and / or in other arrangements. They could also code positions in polar coordinates or coordinates in other coordinate systems. For the position code to be detected, the virtual frame must be determined. This can be done by studying the distance between different brands. The shortest distance between two marks must be derived from two adjacent symbols that have the value 1 and 3 (horizontally) or 2 and 4 (vertically) so that the marks are located on the same raster line between two raster points. When said pair of marks has been detected, the associated raster points can be determined with knowledge of the distance between the raster points and the movement of the marks from the raster points. When two plot points have been located, additional plot points can be determined by means of distances measured to other marks and with knowledge of the relative distance of the screen points. The position coding design described above can encode a large number of unique positions and more specifically the absolute coordinates of these positions. It can be said that all the positions or points that can be encoded by means of the design of position coding together constitute an imaginary surface. Different parts of the imaginary surface can be dedicated to different specific purposes. For example, one area of the imaginary surface may be dedicated to be used as a writing surface, another as a character recognition area and other areas more as various activation icons. Other areas of the imaginary surface can be used in other applications. A corresponding subset of the position coding design can then be used to create, for example, a certain activation icon that can be ordered in an optional location on a product. The coordinates encoded by this subset of the position coding design therefore do not refer to a position in the product but to a position on the imaginary surface, whose position is always dedicated to correspond with this activation icon. In the currently preferred mode, the nominal spacing between the points is 0.3 mm. Any part of the position coding design containing points 6 x 6 defines the absolute coordinates of a point on the imaginary surface. Each point on the imaginary surface is thus defined by a subset of 1.8 mm x 1.8 mm of the position coding design. When determining the position of the 6 x 6 points on a sensor in a device that is used to read the design, a position can be calculated by interpolation on the imaginary surface with a resolution of 0.03 mm. Since each point is encoded with 6 x 6 points each of which can assume one of four values, they can 272 points are coded, whereby the aforementioned nominal intermediate space between the points corresponds to an area of 4.6 million Km2. The absolute position coding design can be printed on any paper or other material that allows a resolution of approximately 600 dpi. The paper can have any size and shape depending on the desired application. The design can be printed by standard offset reproduction. You can use ordinary black ink based on carbon or some other ink that absorbs IR light. This means in fact that other inks, including black ink that is not carbon-based, can be used to superimpose other printed text on the absolute position coding design, without interfering with reading therein. A surface that is provided with the aforementioned design printed with carbon based black ink will be perceived by the human eye only as a slightly gray shading of the surface (1-3% density), which is user-friendly and aesthetically pleasing . Of course, a smaller or larger number of points than those described above can be used to define a point on the imaginary surface and a greater or lesser distance between the points in the design can be used. The above examples are given only to demonstrate a currently preferred design execution.

Claims

NOVELTY OF THE INVENTION CLAIMS 1. - A provision for handling purchases with payment card, characterized by a handheld device (1; 1 ') that is ordered to record the signature of a buyer with a payment card in digital form when the buyer places his signature on a physical voucher of payment card (2; 40) using a compass line (17) ordered in the handheld device, and a signal processing means (16; 33) that is arranged to produce a digital receipt of payment card, which corresponds to the physical voucher of the payment card, by storing the digital signature together with digital information of the purchase related to the purchase with payment card to which said physical voucher of payment card refers. ~ 2.- The arrangement according to claim 1, further characterized in that the handheld device (1, 1 ') is arranged to record additional information in digital form when the buyer writes the additional information using the handheld device in the voucher physical of payment card (2, 40), this additional information in digital form constitutes at least in part said digital information of the purchase that is stored by the signal processing unit. 3. The arrangement according to claim 1 or 2, further characterized in that the handheld device comprises a sensor optical (14) to record images of the surface of the physical voucher of payment card when the buyer writes about it with the handheld device. 4. The arrangement according to claim 3, further characterized in that the arrangement comprises means (16) for identifying a position coding design in said images and for converting the position coding design in each image into coordinates for the position of the handheld device in the physical voucher of the payment card when the image was recorded. 5. - The arrangement according to any of the preceding claims, comprising a reservation of physical blank receipts of payment card that are provided with a position coding design (5) on at least part of its surface. 6. - The arrangement according to any of claims 1-3, further characterized in that the signal processing means is arranged to cause a voucher printer (32) to print said physical payment card voucher. 7. - The arrangement according to claim 6, further characterized in that the signal processing means is arranged to cause said voucher printer to print a position coding design (5) at least in part of said physical card voucher. of payment (40). 8. - The arrangement according to claim 6, further characterized in that the arrangement comprises a stock of papers whose total surface is provided with a position coding design, said paper stock is used to print said physical payment card vouchers. 9. - The arrangement according to any of the preceding claims, further characterized in that the arrangement is arranged so that it is connected to a payment card reader (31) to receive a payment card number from the payment card reader , the payment card number constitutes part of said digital information of the purchase. 10. - The arrangement according to any of the preceding claims, further characterized in that the arrangement is arranged so that it is connected to a cash register (30) to receive at least part of said digital information of the purchase from it. 11. - The arrangement according to any of the preceding claims, further characterized in that the arrangement is arranged to send the digital payment card voucher to an external unit. 12. The arrangement according to claim 11, further characterized in that the termination by the purchaser of the signature in the physical voucher of payment card initiates the sending of the digital voucher of payment card to the external unit. 13. - The arrangement according to any of the preceding claims, further characterized in that the signal processing means is arranged to produce the digital receipt of * payment card when compiling the digital signature and the digital information of the purchase 5 in a file. 14. - The arrangement according to claim 13, further characterized in that the file is closed for alterations a predetermined period after the buyer has finished writing on the physical voucher of payment card. 15. The arrangement according to any of the preceding claims, further characterized in that the signal processing means is adapted to compare the digital signature recorded by the handheld device with a previously stored signature of the owner of the handheld device to verify the signature. 16. The arrangement according to claim 11 and 15, further characterized in that the verification of the signature initiates the sending of a digital receipt of payment card to the external unit. 17. - The arrangement according to any of the preceding claims, further characterized in that the device 20 hand is a digital pen. 18. - A method to handle purchases with payment card, which includes the steps of presenting a physical voucher of a payment card to a buyer, having the buyer place his signature on the voucher physical payment card by a handheld device, which digitally records the signature while it is being written, and produce a digital voucher for a payment card comprising the signature in digital form and digital information of the purchase. 19. The method according to claim 18, which further comprises the step of providing the physical voucher of payment card. 20. - The method according to claim 19, further comprising the step of providing the physical voucher of payment card with a position coding design. 21. - The method according to any of claims 18-20, which further comprises the step of having the buyer write additional information of the purchase on the payment card voucher by means of the hand-held device, which records the additional information in digital form, this additional information in digital form constitutes at least part of said digital information of the purchase. 22. - A payment card voucher comprising at least one writing area (21) that is for the signature of a buyer, characterized in that the payment card voucher is provided with a position coding design that extends over at least said writing area and makes possible the digital recording of said signature. 23. - The payment card voucher according to claim 22, wherein the position coding design is a design of absolute position coding, which encodes coordinates of a plurality of positions in the payment card voucher. 24. - The payment card voucher according to claim 22 or 23, further comprising writing areas (20) that are for additional information of the purchase and that are provided with the position coding design to make possible the digital recording of additional purchase information. 25. - The payment card voucher according to any of claims 22-24, further characterized in that the position coding design comprises a frame and a plurality of symbols, the value of each symbol is determined by the location of a mark in relation to a plot point in the plot. 26. - The payment card voucher according to any of claims 22-25, whose voucher of payment card is used in an arrangement for handling purchases with payment card claimed in claims 1-17.