AU8273682A - Data carrier - Google Patents

Description

Data carrier

This invention is directed to a data carrier being preferably shaped as a personal card holding information about the owner, the card issuing organization, account number, etc. and being intended for manual utiliza¬ tion at the place of use or by means of a read in/read out device com- prised in a terminal equipment, said data carrier comprising means for internal processing of supplied identification information of the owner during a verification process and for generating an acceptance signal, as a result of a verification of the identity and/or right of the owner to use ^"the data carrier. Data carriers or cards of the type indicated above are known before of many different shapes and for different purposes and are in da ly talk named as credit cards. Normally, said cards are dimensioned according to an accepted ISO standard, which means that the card is made from a PVC material being tensil to some extent and having the approximate dimensions of 0,8 mm x 54 mm x 85 mm.

Data cards intended to be handled manually may comprise said informa¬ tion in a embossed print allowing the information to be transferred to a payment verification by means of a print operation.

Data cards intended to be handled by a terminal equipment may com- prise a loop of magnetizable material comprising said information, which terminal comprises a read out device for reading the information which is registered magnetically and eventually a read-in device for a read-in of new information. Data cards of this type may alternatively comprise opti¬ cally readable and writeable areas and may also be of the punched card type holding combination of holes being mechanically readable by the ter¬ minal equipment.

Recently data cards named active cards have began to appear on the market. Said cards are provided with memory circuits and logic circuits of semiconductor type which allows for storing of information and processing of the same internally on the card. For the communication with a terminal equipment cards of this type are provided with a number of externally available electrical connection means or corresponding coupling means.

A general problem when data cards are used is the fact that a lost or stolen data card may be used without authorization by a different person. This problem may be eliminated if the user is obliged to verify his right before the data card may be used.

OMPI In the case of data cards intended for manual handling the verifica¬ tion may be carried out in that the user verfies his identity by presen¬ ting a different identification document. Normally, however, a certifica¬ tion is not required when such a data card is used, among other things due to the fact that this wil create a delay and give rise a queue-up at the places of use. Instead the active control or check is carried out by means of so called black lists comprising the numbers of all blocked accounts, which may have been blocked due to the fact the account holder has not fulfilled his obligations towards the accounting organization or the fact that the account holder has reported the card as lost. The black l sts, being up-dated regularly, means a significant increase of work at the places of use and the situation, when a blocked account is not observed during a manual check, may not be excluded. As a consequence, the card will be used despite the fact that it should not. Furthermore a card, which has been lost for example, may be missused from the time it is re¬ ported as lost until an updated black list is available.

In order to improve the working situation at the places of use so called electronic "black lists" have been developed lately. Then is used a data computer including a memory. In said memory the information about blocked accounts which was previously printed on the black lists is stored. During a check the actual account number is introduced and there¬ after compared with the total of stored account numbers. Summarizing, even if a device of this type allows for an improved check, it may be concluded that an adequate solution to the described problem is not available for the time being.

For data cards intended to be handled by a terminal device one method for preventing unauthorized use of the card means that the card holder will have to verify his right by introducing personal identification code, i.e. a PIN code, via a key set of the terminal equipment. In the terminal the PIN code introduced in this manner and other information which has been read out from the card are evaluated and if the result of the evalua¬ tion is positive the data card is accepted and the transaction may con¬ tinue. Handling of the secret codes means a significant adm nistrative problem to the accounting or card issuing organization. To the card holder it means a practical problem to memorize the secret code comprising nor¬ mally four didgets. The last mentioned problem is aggrevated also by the fact that many persons today hold a number of different data or account cards of this type and, consequently, are forced to memorize a correspon- ding number of different secret codes. This may lead to a situation that a person in this situation, as a support to his memory, writes down the dif¬ ferent codes and keeps the note easily available together w th his credit cards. Obviously this means a drastical decrease of the security which is aimed at by the personal code.

Within a reasonably near future it may be expected that cards of the last mentioned type will be useful more generally as a payment means at a so called POS terminals in shops of many different types. This actualizes a further security risk of the system described above according to which . PIN code is evaluated in a terminal device. People within this field talk about the so called "wardrobe case". Thereby is understood the situation when a card holder may come into contact w th a false terminal at a place of purchase. Then the customer will introduce this PIN-code without any doubts. The PIN-code and yhe associated acount number will be registered ^• by means of an equipment arranged at a different place, that is in the so called "wardrobe". In this "wardrobe" is also kept equipment for forwar¬ ding the transaction correctly. The registered pairs of associated account numbers and PIN-codes may afterwards be used for preparation of false account cards. If these false account cards are used now and then and within an extended geographical area a significant time may elapse until the forgery is detected. The main reason behind this problem is the fact that the account number information and the PIN-code information are transferred to an evaluation device on signal lines being already or which may be made physically available, allowing thereby detection of the infor- aton.-

The US patent specification 4023012 proposes a solution which eli¬ minates the problem of administrating the secret code numbers. According to this solution the card holder may by himself select his secret code when the card is used for the first time. This code is stored on the card and is later on used for verification when the card is used thereafter. In case a person is a holder of a number of different cards of this type it may happen that th s person selects the one and same secret PIN-code for all of these cards in order to make it easier to memorize the PIN-code. Alternatively, this person may select his PIN-code in accordance with a rule which is simple, e.g. as part of his telephone number or citizen identification number. In both of said cases the security is influenced negatively since unvealing of the secret code is facilitated and this opens for a m ssuse of a number of different account cards.

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Λ. WIPO From the US patent specification 3.399.473 a data card is known be¬ fore comprising a number of rotateable and trans!ateable switching means. Said switch means are provided with numeric or alphabetic denumerations. By setting of a secret number or a letter combination, which is known to the holder, the switching means are made to close an internal electric circuit on the data card. When the data card is thereafter used in a ter¬ minal device the so closed electrical circuit may be used as a verifica¬ tion of the holder's authority. Similar technical solutions are disclosed in US patent specifications 3.504.343, 3.287.839, 3.593.292, 3.713.235, 3.762.081, 3.972.138 and 4.100.689. All of the data cards described in said patent specifications have in common the drawback that the holder must memorize a part of or a complete secret code. Furthermore, the con¬ struction of the cards including mechanically adjustable means will have to be considered as a passed state of the technical development. The object of invention is to provide a data carrier or data card in which the drawbacks described above have been eliminated and which makes possible a verification of the user by the use of means accommodated on the card without the use of a secret information which must be memorized. The object of invention is obtained by a data carrier as defined in the introduction and which according to the invention is caracther zed in that said means is provided with a verification device for carrying out said verification process and comprising a sensor device for sensing a finger tip of the owner and obtaining the corresponding papillary line information, said sensor device comprising sensing elements having each a sensing surface for contacting the finger tip and a registration means, which may be controlled by said surface and the registration state of which during the sensing operation is defined dependent on the relative positions of the sensing surface and a papillary line, means for reading said state of registration, signal processing means for forming an identi- fication bit sequence from the registration state information of said registration means obtained by said reading, memory means for permanent storage of a previously and correspondingly obtained reference' b t sequence, comparator means for comparing said identification bit sequence and said reference bit sequence and for generating said acceptance signal when the degree of coincidence between said bit sequencies is acceptable, and means for the control and current supply of said verification device during the verification process.

IPO The problem of memorizing a secret code is eliminated since the iden¬ tification information is received from a finger tip pattern. The finger tip pattern is unique for each individual and thereby provides for a good identification security. Due to the fact that the verification is carried out on the very data carrier the risk of the above related wardrobe case is eliminated and the verification may be carried out with least possible inconvenience for the user by the use of the personal data carrier only. The achieved verification security allows for a use of the data carrier as a mere identification document, for example, at boarder passages between countries and at entrance to restricted areas.

The invention will be described closer in the following with refe¬ rence to embodiments which are shown on the drawings and in which: fig 1_ shows a block diagram of the verification device which is provided on the data carrier; fig 2_ shows one embodiment of a sensing element comprised in the verification device; fig 3 shows a modified embodiment of the sensing surface in fig 2; fig 3a shows a further modi.fied embodiment of the sensing surface; fig 4 shows schematically one embodiment of an optical sensing element; fig 5a ,b,c shows the principal zone of three different finger tip patterns; f g 6 shows a simplified finger tip pat- tern illustrating a method for the reception of in formation; and fig 7 illustrates signal wave forms obtained at the reception of information according to fig 6.

The block diagram shown in fig 1 of the verfication device on the data carrier 1 comprises a sensor device 2 having sensing elements arranged in the shape of a sensing matrix 9 which is indicated. The dimen¬ sion of the sensing matrix is adapted to the finger tip pattern of a thumb. The sensing elements may be read by means of a reading means 3 con¬ nected to the sensing device via a transmission a. By the reading means 3 the sensing elements may be read in accordance with a predetermined reading program and the information will obtain a binary form.

Via a transmission b the binary information may be forwarded to a signal processing device 4 in which the information is transformed so that it may be used for identification. Dependent on the predetermined reading program the information may be modified with respect to the position and orientation of the finger on the matrix during the recording operation. Finally, an identification bit sequence is calculated from said informa¬ tion, the method of calculation and the bit number of said bit sequence

OMPI

Λ,. WIPO « being so that it wil caractherize the finger tip pattern in a way which is adquate with respect to the security of identification.

The identification bit sequence is forwarded to a comparator means 5 via a transmission c. At the same time a reference bit sequence is sup- plied to the comparator 5 from a memory 6, which may comprise a PRO - memory into which the reference bit sequence has been programmed when the data carrier was delivered to the holder. Preferably, the number of bits ot the reference bit sequence and of the ident fication bit sequence are equal and the same is calculated in a manner which corresponds to the cal- culation of the identification bit sequence in an equipment which besides the means which correspond to units 2,3 and 4 also comprises means for programing the memory 6. Method and means for programming a PROM- or a ROM-memory are generally known and for a closer information in this re¬ spect is referred to the special litterature in this field. Block 8 comprises means for control and current supply of the other units. In order to simplify the disclosure the interconnections are shown as one single line, which transmits control signals as well as supply cur¬ rent. The control signals are generated by a micro processor, being pro¬ grammed to control the reading operation of the reading means 3 and the calculation of the signal pro cessing device 4. As will be evident from the following the micro processor may receive control information which is specific to the individual from memory δ. The current supply is obtained from an accumulator which may be exchangeable. The current supply is acti¬ vated by a switch 10, being constantly in a so called "stand by" position. Switch 10 obtains its control information from a touch contact. This con¬ tact may be provided separately on the data carrier or the sensing ele¬ ments of the sensing matrix 9. When the finger tip is pressed against this contact the switch 10 is changed to a closed position and closes thereby the current supply loop. Thereafter the switch will stay closed during a given amount of time necessary for performing the identification process and the eventually following transactions or may al ernatively, it may comprise a bistabile circuit, for example a flip-flop, from which follows that the switch will change from a closed position to an open position when the sensing element is activated a second time. In fig 1 it is assumed that said touch contact comprises one element of the matrix 9, which is indicated by a connection between the switch 10 and the sensing device 2.

OMPI In case the comparator 5 detects a sufficient degree of coincidence between the reference bit sequence from memory 6 and the calculated iden¬ tification bit sequence from the signal processing device 4 an acceptance signal ace is generated and supplied to the indicator 7. The indicator 7 comprises a switching means which may be activated by the signal ace for activating a likewise included light emitting diod (LED) which transmits a green radiation when the acc-signal is received. This green light then indicates the fact that the holder of the data carrier has been able to verify his right to use the same. Alternatively, the block 7 may comprise a switching means which, when receiving the acc-signal, closes a signal path and thereby enables an exchange of data between the data carrier and a terminal equipment.

The data carrier is provided with some given amount of written infor¬ mation, which in fig 1 is illustrated by the name of the card holder, and a mark 11 illustrated as a schematic finger tip for a course adjustment of the finger on the matrix 9.

It is observed that, besides the sensing device 2, the separate blocks are shown in an enlarged scale in fig 1. The physical structure of blocks 3-10 corresponds to prior art of said so called active cards. Blocks 3,4,6 and 8 represent functions which are well known and the cir¬ cuitry thereof corresponds to prior art of integrated semiconductor cir¬ cuits. Said blocks may be made in the shape of one LSI-circuit which may be accommodated on one single silicon wafer or chip. For what remains about the detailed configuration of the separate blocks and the iπtercon- nections on the data carrier according to the invention is referred to US patent specifications 4.001.50 and 3.637.994, disclosing active cards. The French magazine Inter Electronique, May 29, 1978, discloses an active card which is named "electronic check".

The sensing device is built from sensing elements being arranged in the shape of a matrix 9 as is illustrated by the sensing surfaces 9' com¬ prised in the sensing elements 9' in fig 1. In fig 2 is shown one embodi¬ ment of the detailed configuration of the one single sensing element. The sensing surface in this case comprises two metal plates of which one cir¬ cumferential plate 22 connected to a current supply line 25 and one inter- πal plate 21 which, via a registration means 23, is connected to the cur¬ rent supply line 26. Lines 25 and 26, respectively, may be connected to the positive and negative poles, respectively, of said accummulator via

OMPI

Λ, IPO -v, the switch 10. The internal metal plate 21 is seperated from the circum¬ ferential plate 22 by a slot. Because of the disclosed shape of said plates the internal one will determine the resolution at the place or area which is sensed. It is possible to have the dimensions so that the plate 21 may have a diameter of 0,05 mm, the slot may have a width of 0,025 mm and the circumferential plate may have an external diameter of 0,2 mm. This dimensioning of the plate.21 means that the same may separate details of the papillary line pattern having a mutual distance which is greater than 0,05 mm and that approximately 16 sensing points per mm are ob- tained. By the fact that plate 22 fully encloses the plate 21 crosstalk between adjacent sensing elements is el minated due to the fact that a papillary line in contact with the plate 21 of a first sensing element may not have contact with the plate 22 of a second, adjacent sensing element without being also in contact with the plate 22 of said first sensing ele- ment. Contact plates 21 and 22 of each of the sensing elements may be ob¬ tained by photo-etching starting from a cont nous metal layer.

Said registration means 23 comprises a CCD-ele ent which is charged when the current path from line 25 to line 26 is closed via a detail of the papillary line pattern closing the current path between contact plates 21 and 22. If plate 21 and plate 22 are not interconnected by a papillay line said current path will not be closed and as a consequence the CCD- element will not be charged. Alternatively, the registration means 23 may comprise a bistabel element which is switched to a second stable condition when a current of a given magnitude flows through said current path. Fig 3 shows an alternative embodiment of the sensing elements com¬ prised in said sensing matrix. In this case a common contact plat 30 is used for the total number of sensing elements. Consequently, plate 30 cor¬ responds to an integration of the circumferential contact plates 22 accor¬ ding to fig 2 into one continous element. Plate 30 comprises a metal layer in which apertures 30 corresponding to each of the sensing surfaces 9'

(fig 1} have been obtained by photo- etching or a different corresponding method. The common plate 30 is electrically connected to the current supp¬ ly line 25. Centrally of each aperture 30 is provided an internal, point- shaped plate 32 corresponding to the internal plate 21 in fig 2. In the same manner as disclosed in fig 2 the internal plates 32 are respectively connected to the current supply line 26 via a respective registration means. Said point-shaped plates 32 may adequately be formed together with

OMPI IP the apertures 31 during the one and same photo-etching operation. It is observed that the diameter of the apertures 31 has been exaggerated for the sake of clarity.

Fig 3a shows a cross section of a sensing element comprised in the , device according to fig 3. The common contact plate 30 consists of a metal layer. Plate 30 is arranged on an electrically insulating layer 33. In the center of the aperture of hole 31 the internal contact plate 32 is situa¬ ted. Plate 32 connected to the belonging registration means 34 having a terminal 35 for connection to the current supply line 26 (see Fig 3). As shown on the drawing the internal plate 32 is somewhat lowered with re¬ spect to plate 30. By lowering plate 32 is safeguarded that electrical contact between plates 30 and 32 is obtained via the papillary lines only and not via intervals between these lines.

Reception of information from the finger tip pattern may be be ob- tained by the use of the heat transmission from the finger to a sensing device comprising a thermo-seπsitive element. Then the papillary lines can be distinguished because transmission of heat from a papillary line to a sensing element is greater than the heat transmission from the interval between two papillary lines to a sensing element. With reference to fig 3a, the internal contact plate 32 may then be replaced by a thermistor element with temperature dependent resistance. When a galvanic contact is created between plate 30 and thermistor 32 a current is obtained through the current loop closed thereby between lines 25 and 26 (see fig 2) which is dependent on the temperature of the thermistor. Accordingly, the rate of current is decided by the position of the thermistor relative to a papillary line. If the registration means 34 comprises a chargeable CCD- element, its amount of charge after the interval of information reception indicates the position of the papillary line relative to the thermistor 32. By expressing the value of charge by a bit sequence comprising eight bits for example, a "grey coulor scale" is obtained and thereby an in¬ creased amount of information can be used for determining the extension of the papillary line.

An alternative use of said differences of heat transfer is to con¬ struct each sensing element as a thermo-electical transducer. Such a transducer comprises two elements of different metals which are comprised in an electrical circuit. When the metal elements are given different tem- pertures an electromotive force is produced between the elements and an electric current is obtained in the circuit. This current may control said registration means (23, 34). One of the metal elements is arranged adja¬ cent to the surface of the sensing device and the other metal element in contact with and under the first mentioned one. The increase of tempera-

5 ture of the surface adjoining metal elements which occurs when the finger tip is pressed against the sensing device produces a difference in tempe¬ rature between the metal elements and thus creates said current.

The sensing elements may also be of an optical type utilizing the fact that reflected light from an illuminated finger tip comprises infor-

10 ation about the papillary line pattern. This is based on the fact that reflected light from a given sensing point varies with the position of the point within the pattern. Thus, the reflected amount of light from a sen¬ sing point which falls in the middle of a papillary line is greater than the reflected amount of light from a sensing point which falls on the edge

15 of a papillary line. Fig 4 shows schematically an embodiment of such an optical sensing element. It is to be observed that fig 4 illustrates the sensning element in a considerably enlarged scale and firstly serves to illustrate its principal construction. Fig 4 shows a glass fiber 41 the opening 49 of which terminates at the sensing surface of the sensing de-

20 vice. A fi.nger tip is pressed against the sensing surface, which is sche¬ matically shown by line 40. Via a radiation splitting element 42 the fiber 41 is in optical contact with two further fibres 43 and 44. In connection to the input surface of fiber 43 a light emitting diod 45 is arranged. Via the light emitting diod 45 light is suppplied, marked by arrows, into

25. fiber 43 during the sensing interval. The output surface of fiber 44 is connected to a photo transistor 46, which is comprised in a control cir¬ cuit for the control of a switch 47. Switch 47 is series-connected to the registration means 48, which corresponds to registration means 21 and 34 in fig 2 and 3a, respectively, between current supply lines 25 and 26.

30 During the sensing interval ligth is supplied from the light emitting diod 45 into the fiber 43 and via the element 42 to fiber 41. This light is reflected against the finger tip pattern at the output surface 49, which is shown at the output surface by arrows of opposite direction. The reflected light passes through said element to fiber 44 and is directed,

35 via the output surface thereof, towards the phototransistor 46. The photo- transistor 46 then becomes conductive, activating thereby the control cir¬ cuit of switch 47 and the switch is closed. Current may then flow from

OMPI WIPO line 25 to line 26 via the registration means 48. The phototransistor 46 is so biased that the transitor will not be conductive unti the reflected amount of light exceeds a threshold value. The threshold value is so selected that the photo transistor 46 will be activated only when the fiber opening 49 meets a papillary line. The registration state of the registration means 48 will then indicate the relative positions of the fiber opening 49 and a papillary line, and thereby information about the extension of the papillary line along the sensing surface may be obtained. In a modified embodiment of the device in Fig 4 the light emitting diod 45 and the belonging photo transistor 46 are arranged more of less in direct contact with the sensing surface. The optical feedback of the reflected light may be improved by the provision of an intermediary opti¬ cal element.

In case the registration means 48 comprises an analogue registration element, for example a CCD-element, then the photo transistor 46 may alternatively be comprised in a charging circuit for said CCD-element. Because the conductivity of the photo transistor 46 is controlled by the amount of the reflected light the charge of the CCD-element will depend proportionally on the relative positions of a papillary line and the fiber opening 49. Therefore, the "gray- scale information" mentioned above may be obtained by this type of sensing element.

Optical sensing of fingertip patterns have been described in US patent specifications 3.201.961, 4.083.035, 3.859.633 and 4.015.240.

At the time when a data carrier according to the invention is issued the fingertip pattern of one thumb or eventually a different finger of the owner is recorded. From the recorded information a reference bit sequence, which is unique for the owner or holder, is calculated and this sequence is stored in memory 6 (Fig 1). When the holder later on is to identify himself against his data carrier the fingertip information should again be recorded correspondingly in order to allow for a comparision against the reference bit sequence. This means substantially two problems. On the first hand it must be safeguarded that the direction of the fingertip relative to the sensing surface will the same as during the recording of the reference bit sequence or otherwise it must be possible to modify the recorded information with respect to a different orientation of the fingertip. On the other hand the information which is recorded in the sensing device must be read and processed in a way which is reproducible. With regard to the orientation of the fingertip it may be concluded that a physical orientation of the fingertip on the sensing surface with the necessary accuracy is difficult to obtain. In the following is described how to obtain a reference point in the fingertip pattern and, with guidance therefrom, how to obtain information of the fingertip pattern in a reproducable manner.

Fig 5 shows the so called principal zone of a number of different fingertip patterns. The pattern a_ is so called single loop pattern, the patternjj is a so called elliptic pattern and the pattern^ is a so called combined pattern. The papillary line patterns are built around a central point named inner terminus. In the pattern a. the inner terminus is situa¬ ted at 51. In the patterns b_ and c_ the inner terminus may not be defined so obviously, which at the same time illustrates the problem of defining a true reference point in the principal zone. In the pattern a_ point 51 is an obvious choice and in the patterns Jb and_c point 52 and 53, respective¬ ly, are adequate choices. In the following is described how said points are defined by scanning the pattern line by line using a scanning line which is directed transverse to the substantially straight parts of the papillary lines close to the reference point. In Fig 6 is shown a schematical fingertip pattern of the single loop type. A scanning line 61 is moved stepwise in the direction of the arrow across the finger tip pattern. In the sensing device this means that the sensing elements thereof are read out in a manner such that information is obtained from the elements coinciding with said scanning line. Reading of the elements of a matrix in this manner is generally known. For a density of sensing elements, which is assumed for the purpose of illustration only, which corresponds to about two elements per line of the papillary line pattern in Fig 6 and assuming that the registration means of each sensing element positioned on or in connection with a papillary line holds a "1" level and that the remaining elements hold "0" level, the output signals disclosed in Fig 7 are obtained within the sensning window 62 along the scanning lines 61 during scanning from left to right. The output signals are represented as bit streams of 0 and 1 and may then be pro¬ cessed in the signal processing means 4 in control of the microprocessor of block 8. The bow-form of the papillary lines will give rise to a cha¬ racteristic longer sequence of 0 in case the scanning line falls between two papillary lines, as scanning lines 1 or 3 for example, which is illu- strated by the corresponding signals 1 and 3, respectively, in Fig 7. In a corresponding manner a characteristic longer sequence of 1 is obtained n case the scanning lines is tangent to a papillary line bow, as is the case of scanning line 2 in Fig 6 for example, which is illustrated by the cor- responding signal 2 in Fig 7.

The micro processor programme performs the following steps of opera¬ tion: go to the long O-interval in anyone of of the signals 1-9; define correspond ngly positioned long O-intervals of the remaining signals; calculate, for the defined O-intervals, an average bit position which is equal to the integer of the average value; choose as a reference bit the bit of the average position in the signal having the highest order number comprising a long O-iπter- val : define the sensing surface of the sensing element comprising the reference bit as a reference point of the recorded fingertip pattern. If the bit positions of the signals in Fig 7 are numbered 1-17 from left to right is obtained, for the O-intervals in signals 1, 3, 5 and 7, a "bit position number sum" which equals 163. The number of bits within the intervals equals 16. The average bit position will then be 163/16 = 10 3/16 the interger part of which is 10. Accordingly the encircled point 64 in Fig 6 is defined as a reference point.

The signals in Fig 7 are obtained in the sequence shown by scanning the papillary line pattern in Fig 6 by moving stepwise a horizontal scan¬ ning line from top to bottom and a line scanning direction from left to right. In the matrix of Fig 1 this means line by line reading from left to right of the registration means comprised in the sensing elements.

In the patterns according to Fig 5b and 5c the scanning should like- wise be from top to bottom in order for the respective reference points 52 and 53 to be surely defined according to the described method. In further different patterns it may be adequate to carry out a horizontal scanning from bottom to top or a vertical scanning from left to right or vice versa. Therefore, the manner of scanning should be adapted to the type of fingertip pattern in question.

The choice of scanning method may be done in connection with the recording of the reference bit pattern when the data carrier is issued.

OMPI Then as a first step an adequate reference point in the fingertip pattern is selected and thereafter a scanning method which is adequate for estab¬ lishing the same. At the same time the control information required for the scanning method is selected or formed, which information may be fully individual but which preferably comprises a control programme which has been prepared beforehand for the type of fingertip pattern in question.

The rules for decision as described above for establishing the refe¬ rence point may be formed otherwise and may eventually be specifically adapted to each individual . Indiviual zed information as mentioned above with respect to scanning of the sensing elements and the decision rules for the establishment of the reference point are programmed into the memory 6 when the data carrier is issued.

After establishing the reference point the fingertip information is read out by polar reading of the reg stration state of the registration means. This means reading of sensing elements coinciding with one or a number of reading circles having its center in the reference point. The difference of the radiuses between the reading circles is then equal to the center distance between two adjacent sensing elements of the sensing matrix. Alternatively, the one and same reading circle may be used but then the center thereof is each time displaced to another sensing element adjacent to the sensing element established as a reference point, and thereby a decision of the position of the reference point which is even¬ tually wrong is taken into consideration. In Fig 6 is shown a scanning or reading circle 63. The reading of the sensing elements, coinciding with the circle, starts at the intersection to the right between the scanning l ne 7 and the circle and is carried out clockwise. The scanning will result in a signal of the same type as the signals in Fig 7, which signal may be represented by a sequence of 1 and 0. By performing the scanning along the circle 63, having its center in the reference point which may be established in a reproducible manner, principally the one and same bit sequence is always obtained with the dif¬ ference that the position in the bit sequence of the bit which is first read out may vary due to a different relative polar orientation of the papillary line pattern and the sensing matrix, that is a different oriten- tation of the thumb on the sensing device 2 during subsequent recording occasions.

The obtained bit sequence may be used directly as an ident fication

- GREΛ OMPI bit sequence, but if necessary the number of bits may be reduced according to a predetermined algorithm in the signal processing means 4.

From what has been mentioned above is clear that a number of reading circles may be used and then a corresponding number of different bit sequences are obtained. The choise between the alternatives of using dif¬ ferent radiuses or different center points of the reading circles will be made based on a repeated trial of different reading methods when the refe¬ rence bit sequence is formed. The reading method giving the best verfica- tion result is selected and the belonging individualized control informa- tion is programmed into memory 6.

In case of reading of several bit sequencies these may either be used seperately for forming a corresponding number of identification bit sequencies which are thereafter separately compared with the reference bit sequence, or, alternatively, the bit sequencies may be superposed accor- ding to a predetermined algorithm and the result thereof may be used as an identification bit sequence. Also in this case a choice which is specific to the individual may be done when the reference bit sequence is formed. If so, the corresponding control information is programmed into the memory 6. According to what has been mentioned above the sensing elements of the device 2 may comprise analogue registration means 23 (see Fig 2) the analogue values of which may be expressed by bit streams comprising 8 bits for example. It it obvious that the processing of information within the signal processing means 4 will be more extensive in case such registration means are used.

Reverting to the case, which is illustrated in Fig 6, of one reading circle 63, the identification bit sequence obtained as described above comprises from a principal point of view a bit information which is the same as the reference bit sequence but being eventually displaced one or several bit positions. The identification and reference bit sequencies are compared in the comparator 5. At lack of coincidence or a degree of coin¬ cidence which is too low, for example below 90% of the number of bits, the identifiacation sequence is displaced one bit position in a circulating register and thereafter a next comparison is made. This is made repeatedly until a required coincidence is obtained and at that point the acceptance signal ace is generated. The signal ace activates the indicator 7 which verifies the right of the possessor to use the data carrier.

From above is clear that the memory 6 may programmed whith control

OMPI information which is specific for the individual and being related to the fol1owing: horizontal or vertical scanning lines; scanning direction along the scanning lines; - direction of displacement of the scanning lines; decision rule of obtaining the reference point; one or several reading circles; varying radius or center point when using several reading circles; calculation of the identification bit sequence. By choices of this type, which are specific of the individual, the processing of information on the data carrier is simplified with a possi¬ bility to keep the security of verification unchanged. An increased number of choices which are specific to the individual will further simplify the signal processing on the data carrier. This in turn requires a correspon- dingly increased data processing capacity when the reference bit sequence is formed. However, this is not a problem.

With the aim to clarify the description above it has been directed to a data carrier having on the carrier an indicating means which directly indicates the outcome of the verification process. A data carrier of this type will allow for a complete protection against unauthorized use of pro¬ perly issued, authentic data carriers because the same may be activated by the legitimate owner only. Consequently, this prevents an unauthorized use of lost or stolen cards. However, it is underlined that a so shaped card will give no protection against false data carriers provided with a corre- spondiπg indicating means because of the fact, that said indicating means may be activated by an arbitrary type of switch without the need of carrying out a verification process as described above.

The last mentioned means a problem in the first hand when the data carrier is intended for a manual use. An improved protection in this case may be obtained by combining the verification device according to the invention with a structure of the data carrier or card itself which is difficult to falsificate, which may be obtained by providing the card with a photograph of the owner or graphic pattern of the type which is used on banknotes. For data carriers intended to be handled by a terminal equipment the authenticity of the data carrier and preferably also the authenticity of the terminal is verified by using instead said acceptance signal for the

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OMPI

Λ, WIPO activation of a signal path for the exchange of identification information between the data carrier and the terminal. The "electronic block list" mentioned above may have the form a simple terminal equipment comprising a read in/read out device. After the generation of said acceptance signal and switching of said switching means the data carrier is introduced into the read in/read out device. Information, which is stored on thέ data carrier, about the account number of the owner, being preferably protected as a matter of information or physically by the structure of the storage means, is supplied to the terminal and, after being eventually signal pro- cessed, compared to blocked account numbers. At lack of coincidence an indication lamp is activated which will then indicate that the owner is an authorized person, that the data carrier is authentic, and that the corre¬ sponding account is not blocked.

Above a number of US patents have been referred to from which it is known before to use a finger print as a means for identification. Equip¬ ment for the recording and processing of finger print information are described in said patent specifications. Said equipments are intended to be positioned at the places of use, for example in a bank locality. It may be concluded that equipments of this type, if used at all, has not come into practice to an extent which should be motivated by the security of identification which is obtainable. One important reason behind this is the fact that it is not desireable from the side of the users, that is banks etc., to introduce a method of identification of such a "criminal nature", that is the fact that finger prints have been used since long ago for identification of criminals and that very extensive data registers about finger prints are available. An owner of a data carrier which is beyond any reproach is expected to feel a phsycological barrier or unwil¬ lingness against such an identification method. The judgement has been that this, in combination with the hygenical and practical objections which may follow from the fact that several persons use the one and same equipment, may possibly have a negative influence on the relations to cus¬ tomers.

It may be appreciated that the data carrier according to the inven¬ tion eliminates the objections mentioned above because the identification is carried out internally on a personal data carrier and not in a central* equipment, which may be suspected to be connected to a finger print regis¬ ter of criminals, and because the recording of the finger tip information is carried out in connection with the "thumb grip" which is normally used when the data carrier is handled by its owner. In this connection is is observed that the position of the matrix 9 in Fig 1 should be regarded as an example and obviously this position may be fitted to said "thumb grip".

O PI

Claims (12)

Claims.

1. A data carrier being preferably shaped as a personal card holding information about the owner, the card issuing organization, account number, etc., and being intended for manual utilization at the place of use or by means of a read in/read out device comprised in a terminal equipment, said data carrier comprising means for internal processing of supplied identification information of the owner during a verification process and for generating an acceptance signal as a result of a verifi¬ cation of the identity and/or right of the owner to use the data carrier, c h a r a c t e r z e d in that said means is provided with a verifica- tion device for carrying out said verification process and comprising a sensor device (2) for sensing a finger tip of the owner and obtaining the corresponding papillary line information, said sensor device comprising sensing elements having each a sensing surface (9') for contacting the finger tip and a registration means (23; 34), which may be controlled by said surface and the registration state of which during the sensing opera¬ tion is defined dependent on the relative positions of the sensing surface and a papillary line, means (3) for reading said state of registration, signal processing means (4) for forming an ident fication bit sequence from the registration state information of said registration means ob- tained by said reading, memory means (6) for permanent storage of a pre¬ viously and correspond ngly obtained reference bit sequence, comparator means (5) for comparing said identification bit sequence and said refe¬ rence bit sequence and for generating said acceptance signal (ace) when the degree of coincidence between said bit sequencies is acceptable, and means for the control and current supply (8, 10) of said verification device during the verification process.

2. A data carrier as claimed in claim 1, c h a r a c t e r i z e d by an adjustable switching means (7), being arranged, for activating, at the reception of said acceptance signal, a visually readable indicating means (7), or, alternatively, a signal path for the transmission of information between the data carrier and a terminal equipment.

3. A data carrier as claimed in claim 1 or 2, c h a r a c t e r i z e d in that each sensing surface comprises an internal contact plate (21) and a surrounding contact plate (22), which is arranged to surround but sepa¬ rated from the internal plate by a non-conductive slot, which may be over- bridged electrically by a detail of the finger tip pattern, said sur¬ rounding plate being electrically connected to a first current supply line (25), and said internal plate being electrically connected to a second current supply line (26) via a belonging registration means (23), a supply of current to said registration means being thereby possible when said slot is overbridged.

4. A data carrier as claimed in claim 3, c h a r a c te r i z e d in that said surroundning contact plates are integrated into a common contact plate (30), comprising for each of said sensing elements a ring-shaped hole (30)corresponding to said slot and in the center of which is provided a pointshaped, internal contact plate (32).

5. A data carrier as claimed in anyone of the previous claims, c a¬ r a c te r z e d in that each sensing surface comprises an element the resistance of which is temperature dependent (for example 32 of Fig 3) or, alternatively, an element of a thermoelectrical transducer comprising two elements of different types of metal, the magnitude of the current which is supplied to said registration means being thereby controlled by the transmission of heat from the finger tip to the sensing surface.

6. A data carrier as claimed in claim 1 or 2, c h a r a c t e r i z e d in that each sensing surface comprises an optical element (41, 49) for the supply of light to a contacting detail of the finger tip and for the re¬ ception of reflected light from the same detail, said sensing element com¬ prising a light source (45) and a means (46) which is sensitive to said reflected light and which is arranged to control the registration means (48).

7. A data carrier as claimed in anyone of the previous claims, c h a- r a c t e r i z e d in that said registration means (23; 24) comprises an element for an analogue registration, said elements generating an ana- logue registration va ue dependent on the supply of current, or, alterna¬ tively, a bistabile element which is made to change its state when a current which is supplied exceeds a threshold value.

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O PI WIPO

8. A data carrier as claimed in anyone of the previous claims, c a¬ r a c t e r i z e d in that it comprises means (8, 10) for activating temporarily the verification device, in which said means may comprise a b stabile element which may be controlled via a touch contact element and which is so arranged that it will inactivate the device at a repeated operation of the touch contact element.

9. A data carrier as claimed in anyone of the previous claims, c a¬ r a c t e r i z e d in that it comprises a memory area (6) for a per a- nent storage of control information regarding to a method for reading the registration means and decision rules for forming said identification bit sequence.

10. A data carrier as claimed in claim 9, c h a r a c t e r i z e d in that in said memory areas is stored control information having regard to the decision of a reference point (51, Fig 5a) in the finger tip pattern and the reading of recorded finger tip pattern information from the regi¬ stration means coinciding with a reading circle (63) having its center in said reference point.

11. A data carrier as claimed in anyone of the previous claims, c a¬ r a c t e r i z e d by memory areas for a permanent storage of control information which is specific of an individual, said control information being establ shed during forming of the reference bit sequence.

12. A data carrier as claimed in claims 10 and 11, c h a r a c t e- r i z e d in that said memory areas for storage of control information which is specific of an individual are made to store information having regard to one or several of the functions which follow: line-by-line scan- ning of the registration means by the use of horizontal or vertical scan¬ ning lines; reading direction along said lines; direction of displace¬ ment of said reading lines; decision rules for the evaluation of the information which has been read for establishing said reference point; number of reading circles for reading the finger tip pattern informa- tion; radius or center of a circle when several reading circles are used, rules for establishing said identification bit sequence from the finger tip pattern information which is read along said circles.