WO1992018977A1 - Support de donnees magnetique, son procede de fabrication, systeme de donnees et dispositif de decodage de donnees - Google Patents

Support de donnees magnetique, son procede de fabrication, systeme de donnees et dispositif de decodage de donnees Download PDF

Info

Publication number
WO1992018977A1
WO1992018977A1 PCT/GB1992/000749 GB9200749W WO9218977A1 WO 1992018977 A1 WO1992018977 A1 WO 1992018977A1 GB 9200749 W GB9200749 W GB 9200749W WO 9218977 A1 WO9218977 A1 WO 9218977A1
Authority
WO
WIPO (PCT)
Prior art keywords
magnetic
data
pattern
recording material
layer
Prior art date
Application number
PCT/GB1992/000749
Other languages
English (en)
Inventor
Charles Richard Jarvis
David John Silvester
Original Assignee
Gec Avery Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gec Avery Limited filed Critical Gec Avery Limited
Publication of WO1992018977A1 publication Critical patent/WO1992018977A1/fr

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
    • G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
    • G11B5/716—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by two or more magnetic layers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers
    • G11B5/855—Coating only part of a support with a magnetic layer

Definitions

  • This invention relates to a magnetic data medium, for example a magnetic tape, a bank card, a credit card, a telephone prepayment card, or a railway ticket.
  • bank cards and credit cards are typically of the "read only" type, in which relevant account data is initially recorded in a layer formed, for example, from magnetic tape comprising a magnetic coating on a substrate, and thereafter read back for each transaction without being changed.
  • Some types of card for example telephone prepayment cards, require data to be written to the card at each transaction for which it is used, for example leaving a record of prepaid telephone units remaining from the original value of the card.
  • Such cards typically use a layer of high coercivity material to resist fraud, since it is difficult to record onto high coercivity material and such recording cannot readily be changed by the user of the card. It is convenient to produce such magnetic layers by printing, for example by screen printing, the magnetic recording material in ink form onto the card substrate.
  • Some types of telephone prepayment card have read-only data recorded in certain areas of the card onto originally unmagnetised magnetic recording material.
  • each data transition is typically from +1 to 0, from 0 to -1, or vice versa, giving a signal transition half that of the changeable data or read-write areas of the card which, as with most conventional magnetic tape recordings, have transitions from +1 to -1 and vice versa.
  • a protective plastic coating typically a PVC layer about 40 microns thick
  • the read head must receive a sufficiently strong signal across this 40 micron spacing.
  • the magnetic permeability is, of course, a property of the magnetic recording material or materials used, whilst the value of the permeance is a function of the permeability and the dimensions of the magnetic layer.
  • the signal strength is a direct function of permeance which in turn is a direct function of the thickness of the magnetic layer.
  • a security magnetic recording support prefferably in the form of a strip and to comprise a magnetic recording base having a substantially constant thickness and, in certain areas, reinforcements or increased thickness zones whose coercivity is identical to that of the magnetic recording support base and whose thickness exceed by at least 40% the average thickness of the magnetic recording support base.
  • This structure is achieved by the transfer to a first transfer tape of reinforcements from a second transfer tape by the application of heat and pressure by means of a heated hammer.
  • the first transfer tape, bearing the localised reinforcements from the second transfer tape is then transferred into alignment with an object, such as a credit card, which is positioned on a support.
  • a vertically movable heated hammer having a head specially shaped to correspond to the element to be applied, is then used to engage the transfer tape on the obj ct to be processed and, under the combined action of temperature and pressure, the magnetic part of the tape is transferred to the object.
  • the credit card, or other object is provided with the magnetic support which may subsequently be covered with a protective film.
  • the strip so formed comprises a matrix of heat-meltable resin and magnetisable particles, the thickness of the magnetisable support being increased in certain defined or undefined areas in such a way that, after the magnetic recording of a signal, the corresponding reading signal is modulated in amplitude by a value greater than that obtained by the small variations in thickness resulting from the manufacture of prior art supports. This amplitude modulation of the reading signal is then transformed into a code corresponding to the thickness variations of the magnetic support.
  • a magnetic data medium such as a magnetic tape, a bank card, a credit card, a telephone prepayment card, or a railway ticket
  • One aspect of the invention is accordingly concerned with magnetic data medium including a substrate bearing a region of magnetic recording material whose thickness varies in accordance with a predetermined pattern to define a pattern of varying magnetic permeance.
  • the magnetic recording material is defined by a first layer printed onto the substrate and by a second layer in a discontinuous pattern on the first layer. In this manner additional security can be incorporated into a magnetic data medium by varying the printing pattern between successive layers to produce areas with different thicknesses.
  • the resultant signal transitions from the magnetised material from, say, one printed thickness to two or more printed thicknesses can be detected, thus enabling a wide range of markings such as magnetic signatures or security markings, to be incorporated in the magnetic recording material of the magnetic data card, without the use of transfer tapes or complex tooling, such as heated hammers housing specially profiled heads.
  • the magnetic recording material is additionally defined by a third layer printed in a different discontinuous pattern on the second layer.
  • the substrate upon which the magnetic material is applied may be of any convenient material, for example plastics, paper or cardboard, and of any desired shape or thickness.
  • the substrate may be a plastics film or tape.
  • a tape in accordance with the invention may be applied to a further substrate such as card or plastics, in conventional manner, or may be utilised on its own.
  • the thickness of the magnetic recording material varies in discrete equal steps or multiples thereof.
  • An overlying disguising layer may be provided to avoid ready copying of the pattern.
  • the pattern of varying magnetic permeance includes a portion of the substrate free from magnetic material. In this manner portions of the structure have no magnetic material thereby providing a greater range of magnetic transitions for the "signature".
  • an additional level of security may be introduced, if desired, by writing blocks of data into the data region with varying levels of magnetic intensity in the magnetic write head or recording head in a pattern corresponding to the predetermined pattern, such that the signals, when read, appear to be at the same uniform level.
  • the correct pattern of varying intensity recorded on to a fraudulent card without the same pattern of thicknesses would also produce varying read levels, again readily revealing the attempted fraud.
  • Each layer of magnetic recording material can be applied by any printing technique suitable for the magnetic material and the selected substrate, more preferably by screen printing.
  • the substrate is preferably deformed to accommodate the different printed layers thereby presenting a uniform planar surface.
  • a non-magnetic coating layer may be applied over the resultant pattern of magnetic recording material.
  • the magnetic recording material is sandwiched between the uniform planar surface of the deformed substrate and a cover layer laminated to the substrate.
  • the stripe In the case of bank cards having a single stripe of magnetic recording material thereon, it is conventional to divide the stripe into three distinct tracks, different types of data being recorded on the different tracks. In such a case, a portion of the stripe corresponding to only one, or only two, of the tracks may be formed with a varying thickness to provide security coding. Alternatively, the whole width of the strip may be coded, with the normal data recorded over the coded strip, or only a longitudinal portion of the strip may be coded.
  • the first layer may also define a discrete data region of substantially constant magnetic permeance. The discrete data region may be separate from the region defining the pattern of varying magnetic permeance. The region of magnetic recording material and the substrate may alternatively be substantially coextensive.
  • Telephone cards typically have multiple data areas, for example corner regions used to permit access of the card into the reading machinery and a central stripe divided into three separate regions, the middle region being rewritten with the residual value of the card, and the outer regions of the stripe containing read only data representing the initial value of the card and, perhaps, security data.
  • the variable thickness "signature" in only one of the areas or in more than one, as desired.
  • the residual value data area may be provided with a thickness pattern coding, and when the card is read by the card reading machinery, the reader could be arranged to test for the underlying pattern after the value data is erased and before the value remaining data is rewritten at the end of the transaction.
  • the region of magnetic recording material also bears magnetically-recorded data.
  • the intensity of the magnetically-recorded data may vary in accordance with the predetermined pattern whereby a magnetic reading head passed along the axis will detect a substantially uniform signal level.
  • the magnetic data medium of the invention may comprise a plurality of data regions on its surface, separated by non-magnetic areas, at least one data region consisting of magnetic material whose permeance varies in accordance with the invention.
  • the data regions may be used as read-only or read-write regions, with a single medium having any combination of these in multiple data regions.
  • the whole of one surface of a data card may be used as a data region.
  • a magnetic data recording stripe on a data card or the like in accordance with the invention will yield signals in the form not merely of transitions of +1 to -1, or +1 to 0 and 0 to -1, for example, but complex combinations of such signals with transitions arising from thickness variations, for example 1 to z / ⁇ , 2 / 3 to 1 / 3 , and 1 / 3 to 0.
  • Another aspect of the invention provides a data system comprising a magnetic data medium (or a plurality of such media) in accordance with the invention, and a reader device comprising reading means for reading the pattern of varying signal levels or remanance along the axis of the data medium arising from said predetermined pattern and from the data recorded thereon, means for storing data corresponding to said predetermined pattern, and processing means employing said stored data to process the signals read by said reading means to extract therefrom the recorded data.
  • a method of making a magnetic data medium which includes a substrate bearing a region of magnetic recording material whose thickness varies in accordance with a predetermined pattern to define a pattern of varying magnetic permeance, includes printing a first layer of magnetic recording material directly onto at least a portion of the substrate, and printing a second layer of magnetic recording material in a discontinuous pattern on the first layer.
  • the method preferably includes printing a third layer of magnetic recording material in a different discontinuous pattern on the second layer. If desired at least one portion of the substrate may be kept free of magnetic recording material.
  • the method includes deforming the substrate is after printing of the layers to define a uniform planar surface.
  • the method may also include magnetically recording data over the pattern of varying magnetic permeance.
  • a data system includes a magnetic data medium formed from a substrate bearing a region of magnetic recording material whose thickness varies in accordance with a predetermined pattern to define a pattern of varying magnetic permeance and a reader device, the reader device including reading means for reading the pattern of varying signal levels along the region arising from the predetermined pattern and from data recorded thereon, storage means is provided for storing data corresponding to the predetermined pattern, and processing means is provided to employ said stored data to process the signals read by said reading means to extract therefrom the recorded data.
  • a data system may include a reader device and at least one magnetic data medium formed from a substrate bearing a region of magnetic recording material whose thickness varies in accordance with a predetermined pattern to define a pattern of varying magnetic permeance, and having data signals recorded thereon, the reader device being arranged to read the composite signal comprising the data signal recorded on the pattern of varying magnetic permeance, and to separate the data signal from the underlying magnetic signature defined by the pattern of varying magnetic permeance.
  • the reader device may be arranged to read the data signal from the pitch of the composite signal and to read the magnetic signature from the amplitude of the composite signal.
  • the reader device may be arranged to store the composite signal prior to erasing the data signal, subsequently to read the magnetic signature, subsequently to use the magnetic signature to decode the composite signal to obtain the data signal.
  • the reader device may be arranged finally to restore the data signal for the region.
  • the decoding device may, for example, be interposed between the reading head of a conventional data card reading device and the data handling components thereof, or at some other stage in the data transmission chain, thus permitting existing card reading terminals to be readily adapted to receive data cards in accordance with the invention.
  • Figure 1 is an enlarged sectional view through the data region of a data card in accordance with one embodiment of the invention
  • FIG. 2 is a diagrammatic representation of a bank card in accordance with the invention.
  • FIG. 3 is a diagrammatic representation of a telephone prepayment card in accordance with another embodiment of the invention.
  • FIGS 4, 5 and 6 are diagrammatic representations of bank cards according to further embodiments of the invention.
  • Figure 7 is perspective view of a conventional card reading device modified in accordance with another aspect of the invention.
  • FIGS. 8 and 9 are block diagrams of two other modified card-reading devices.
  • a magnetic data card is formed from a first flexible plastics substrate layer 1 with a magnetic stripe 2 printed thereon in three layers.
  • the first layer 3 is a continuous layer of magnetic material applied in an appropriate pattern on the substrate 1 by a silk screening technique using an ink comprising magnetisable particles suspended in a suitable hardenable liquid medium.
  • a second layer 4 is then printed over the first layer 3 in a discontinuous pattern leaving apertures.
  • a third layer 6 is then printed onto the hardened layer 4 in a different discontinuous pattern with different apertures such that the overall thickness of magnetic material varies along the stripe stepwise from a maximum of three layers to a minimum of one layer so that, when the strip is magnetised by a uniform magnetising field, transitions between three levels of magnetisation can be detected along the strip in a predetermined pattern constituting, in effect, a magnetic "signature".
  • a first cover layer 8 Overlying the magnetic stripe, and indeed the whole face of the card, is a first cover layer 8 providing a surface to the card at a uniform level.
  • the cover layer 8 may be applied by any suitable conventional coating technique, but would preferably be by lamination to ensure planarity of the surface.
  • a second flexible substrate layer 9, bearing printed data, designs and/or other indication on its lower face is positioned beneath the first substrate layer 1, with a second cover layer 10 on the printed face.
  • the three printed layers adopt the configuration shown in Figure 1, with the first substrate layer 1 deforming to accommodate the different thicknesses to present a uniform planar upper layer in contact with the cover layer 8.
  • Figure 2 shows a bank card 20 having a continuous magnetic stripe 21 extending along its length.
  • the magnetic stripe 21 is formed with three parallel regions 21a, 21b and 21c, the first two of which are essentially formed from three coextensive layers of magnetic recording material, printed onto the card in the general manner described hereinbefore with reference to Figure 1, while the third portion 21c is formed with a pattern of differing thicknesses, again as described with reference to Figure 1.
  • the pattern of thicknesses varies along the length of the card according to a predetermined pattern of 3, 2 and 1 layers, represented by different shading and no shading.
  • the three areas 21a, 21b and 21c represent the regions of a conventional bank card or credit card occupied by the three magnetic tracks, of which one or more may remain unused.
  • the magnetic tracks encode data relating to, for example, the personal identification number (PIN) of the holder and perhaps data relating to the maximum size of transaction permitted, with account-identifying data.
  • the track 21c which is encoded with differing thicknesses may have additional data magnetically recorded in the track in conventional manner, the reading head being adapted to detect the data and, separately, the underlying encoding due to the varying thicknesses.
  • Figure 3 shows a typical telephone prepayment card for use with a card-operated public telephone.
  • the card has seven distinct data regions consisting of areas of magnetic recording material printed thereon as hereinbefore described.
  • Four corner regions 30, 31, 32 and 33 may be encoded with data which releases the reader mechanism to admit the card to the reader, while three centrally arranged longitudinal regions 34, 35 and 36 carry data relating to the value of the card, as well as security data.
  • the central region 35 is typically used to store the residual value of the card after use. In use, the reader reads the residual value from this region, wipes the data from the region and then at the end of the transaction, rewrites on to the region data representing the new residual value.
  • Regions 34 and 36 contain, for example, security data and data relating to the original value of the card.
  • any of these regions may be printed with a pattern of thicknesses as described with reference to Figure l, the appropriate reading head in the reading mechanism being arranged to detect the pattern of signals arising from the variation in thickness.
  • the corner regions 30 and 31 may be encoded with a predetermined pattern of thicknesses instead of, or as well as, the predetermined magnetic signal recorded in the regions.
  • the reader mechanism may be programmed to refuse admission of the card.
  • one of the central regions 34, 35 or 36 may bear an underlying thickness pattern coding which, after erasure of the residual value data, and before rewriting of the new residual value, may be scanned to determine whether a correct pattern is present, and therefore whether use of the telephone may be authorised. Since it would be very difficult for the correct pattern to be reproduced fraudently, security of the card is greatly increased.
  • the card illustrated in Figure 4 is a modified form of standard ISO bank card having a magnetic stripe 40 adjacent to one edge, with data written to some or all of the three parallel tracks therealong. Occasionally, such data extends over only a part 40a of the length of the stripe, leaving the remainder 40b free of data.
  • at least a part of this remainder 40b is provided with permeance variation coding, and a uniform write (or record) signal is applied to the coded part during manufacture of the card, whereby a permeance code pattern may be detected during reading of the card in a card reader. For example, the detection of the presence of code pattern may permit a higher transaction limit than for a card without the code pattern.
  • Data recorded in the data part 40a of the stripe 40 may include a code activating the reading head in the card reader to continue reading beyond the end of the data part 40a. It would be possible to encode the card with any of a plurality of different codes, with the data in part 40a including an indication of which code had been used for the part 40b.
  • the whole of the stripe 40 bears a permeance variation coding, with the data in part 40a being recorded with a signal level pattern corresponding to but opposite to the underlying coding.
  • Figure 5 illustrates a card which is provided with a standard bank card stripe 50 and a control stripe 51 of the type used in magnetic prepayment cards such as that illustrated in Figure 3.
  • the control stripe 51 is divided into three portions 51a, 51b and 51c, the outer portions 51a and 51c typically being "read-only" data areas, while the middle portion 51b is a "read-write” data area.
  • the stripe 50 may be provided with permeance encoding, as described with reference to Figure 2 or Figure 4 and/or any of the portions of the central stripe 51 may have permeance encoding.
  • Figure 6 illustrates a memory card used for the storage of data and having the whole of one face thereof coated with magnetic recording material, applied such that at least a part thereof is permeance encoded as hereinbefore described.
  • the whole of the surface may be encoded, or regions corresponding to part or all of one or more tracks of data may be encoded. Examples of such regions are indicated by reference numerals 60 in Figure 6.
  • FIG 7 illustrates a conventional card "swipe" device 70 modified to operate in accordance with one aspect of the invention.
  • the device 70 has a channel 71 running along its uppermost surface into which a card, for example of the type illustrated in Figure 4, may be inserted with its magnetic stripe downmost.
  • Running the card along the slot, commonly referred to as “swiping" the card passes the magnetic stripe past the reading head so that data therein can be read.
  • This data normally passes via a cable 72 to further data handling stages, for example for obtaining clearance for a transaction, or effecting the transaction by electronic finds transfer in conjunction with keyed-in data.
  • a decoding device 73 is interposed between the "swipe" device 70 and the further data handling stages.
  • the decoding device 73 receives the signals from the "swipe" device 70 and checks for the presence of the correct reassurance pattern in the non-data portion 40b of the stripe 40, passing a suitable enabling signal to the further data handling stages if the pattern is present.
  • Figure 8 and 9 illustrate different ways of modifying existing card-reading devices to operate with magnetic data media in accordance with the invention.
  • the magnetic reading head 80 is connected via a decoding device 81 to the existing electronics 82 for processing, while in that of Figure 9, the reading head 80 is connected to the existing electronics 82 which is in turn connected to other parts of the data handling chain, represented by the dotted line, and then to the decoding device 81.
  • the decoding device 81 serves essentially the same function as that described with reference to Figure 7.
  • the stripe of varying permeance would be directed along the tape preferably at its start, although it could occur anywhere, or even repeatedly along the tape.
  • the printed layers could be printed on the side of the tape remote from its general magnetic coating, or could be printed on the tape before it is coated, or could be printed on the general magnetic coating.

Landscapes

  • Credit Cards Or The Like (AREA)
  • Magnetic Record Carriers (AREA)

Abstract

Une carte de données magnétique comprend une zone de données revêtue d'une matière d'enregistrement magnétique dont l'épaisseur mesurée selon l'axe varie en fonction d'un dessin prédéterminé et sert de filigrane magnétique disposé sous les données enregistrées et utilisable pour vérifier l'authenticité de la carte. L'épaisseur variable est réalisée en imprimant une première couche (3) de matière d'enregistrement magnétique directement sur un substrat (1); une deuxième couche (4) correspondant à un dessin discontinu est appliquée sur la première couche (3) et une troisième couche (6) correspondant à un dessin discontinu est appliquée sur la deuxième couche (4).
PCT/GB1992/000749 1991-04-23 1992-04-23 Support de donnees magnetique, son procede de fabrication, systeme de donnees et dispositif de decodage de donnees WO1992018977A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB919108701A GB9108701D0 (en) 1991-04-23 1991-04-23 Magnetic data medium
GB9108701.5 1991-04-23

Publications (1)

Publication Number Publication Date
WO1992018977A1 true WO1992018977A1 (fr) 1992-10-29

Family

ID=10693797

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1992/000749 WO1992018977A1 (fr) 1991-04-23 1992-04-23 Support de donnees magnetique, son procede de fabrication, systeme de donnees et dispositif de decodage de donnees

Country Status (3)

Country Link
GB (2) GB9108701D0 (fr)
WO (1) WO1992018977A1 (fr)
ZA (1) ZA922948B (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8538801B2 (en) 1999-02-19 2013-09-17 Exxonmobile Research & Engineering Company System and method for processing financial transactions
CN106778989B (zh) * 2016-11-22 2020-04-21 中钞特种防伪科技有限公司 防伪元件及防伪产品

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0033041A1 (fr) * 1980-01-25 1981-08-05 Rhone-Poulenc Systemes Support d'enregistrement magnétique sécuritaire et procédé pour sa réalisation
EP0162349A2 (fr) * 1984-05-24 1985-11-27 International Business Machines Corporation Milieu d'enregistrement de données
WO1987005728A1 (fr) * 1986-03-12 1987-09-24 Skidata Computerhandelsgesellschaft M.B.H. Procede pour assurer un support de donnees contre les falsifications, support de donnees assure contre les falsifications et dispositif pour le traitement, le façonage et le controle du support de donnees
US4777540A (en) * 1986-03-18 1988-10-11 American Magnetics Corp. Magnetic card reader with head stop arrangement
WO1990007755A1 (fr) * 1988-12-23 1990-07-12 Coin Controls Limited Systeme de securite ameliore

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2452140A1 (fr) * 1979-03-21 1980-10-17 Automatisme Cie Gle Titre magnetique

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0033041A1 (fr) * 1980-01-25 1981-08-05 Rhone-Poulenc Systemes Support d'enregistrement magnétique sécuritaire et procédé pour sa réalisation
EP0162349A2 (fr) * 1984-05-24 1985-11-27 International Business Machines Corporation Milieu d'enregistrement de données
WO1987005728A1 (fr) * 1986-03-12 1987-09-24 Skidata Computerhandelsgesellschaft M.B.H. Procede pour assurer un support de donnees contre les falsifications, support de donnees assure contre les falsifications et dispositif pour le traitement, le façonage et le controle du support de donnees
US4777540A (en) * 1986-03-18 1988-10-11 American Magnetics Corp. Magnetic card reader with head stop arrangement
WO1990007755A1 (fr) * 1988-12-23 1990-07-12 Coin Controls Limited Systeme de securite ameliore

Also Published As

Publication number Publication date
GB2255046A (en) 1992-10-28
ZA922948B (en) 1992-12-30
GB9208828D0 (en) 1992-06-10
GB9108701D0 (en) 1991-06-12

Similar Documents

Publication Publication Date Title
US4985614A (en) Object verification apparatus and method
EP0275117B1 (fr) Objet vérifiable
US5972438A (en) Magnetic recording medium and method of manufacture of same
US3683413A (en) Method for merging variable and fixed magnetic data on a credit card or the like
EP0227781B1 (fr) Cartes a codage magnetique
EP0276814A2 (fr) Système et méthode de vérification d'objets
US5650606A (en) Accurate read/write head for preventing credit card alteration and counterfeiting of debit cards
US5627357A (en) Magnet information cards
JPH0678037B2 (ja) 認証識別媒体の認証装置
JPH08202842A (ja) 磁気カード類
WO1992018977A1 (fr) Support de donnees magnetique, son procede de fabrication, systeme de donnees et dispositif de decodage de donnees
EP0938720B1 (fr) Support d'enregistrement et procede d'etiquetage d'un article de valeur
US6241152B1 (en) Card processing apparatus and method
JP2005129183A (ja) 記録媒体、記録媒体の判別方法及びカードリーダ
JPH07214955A (ja) 真正さがチェックされるカード状の被検出物とその製造方法
EP0146056A2 (fr) Support d'enregistrement magnétique et son procédé de fabrication
WO1996030880A1 (fr) Systeme de securite pour documents a piste magnetique d'enregistrement d'informations
JPH0827883B2 (ja) 磁気カ−ドおよびそのための磁気記録再生方法および装置
JP2706714B2 (ja) 磁気記録媒体とその製造方法
JPS63171475A (ja) カ−ドの真偽判定方法
JP2908535B2 (ja) 磁気記録式券片の信号判読方法
Tompkin et al. Low-density diffractive optical memories for document security
JPH0689376A (ja) 改ざん不能な磁気カード
JPS63149815A (ja) 磁気ヘツド
JP2601273B2 (ja) 磁気カードの処理方法

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU MC NL SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA