Card, an assembly, a method of assembling the card and a method of outputting information

Abstract

A card configured to output an magnetic field on or at a surface thereof, the card comprising an elongated magnetically conducting material on or at the surface of the card, the magnetically conducting material having a first and a second guide ends, and a field generator positioned so as to feed a magnetic field into the magnetically conducting material. The magnetically conducting material is positioned at the position where the reading head travels and forms a return path for the field generated by the field generator, whereby field from the generator is fed to the reading head via the magnetically conducting material.

Claims

1. A card configured to output a magnetic field on or at a surface thereof, the card comprising: an elongated magnetically conducting material on or at the surface of the card, the elongated magnetically conducting material having a first guide end and a second guide end, the elongated magnetically conducting material extending at least 50% of a width or length of the card, and a field generator positioned so as to feed a magnetic field into the elongated magnetically conducting material, the field generator including an elongated coil extending at least substantially parallel to a longitudinal direction of the elongated magnetically conducting material, where the elongated magnetically conducting material and the field generator, at a position along the longitudinal direction of the elongated magnetically conducting material and in a plane perpendicular to the longitudinal direction, have non-overlapping cross-sectional circumscribing curves.

2. A card according to claim 1, the card having an outer, at least substantially straight side and wherein the elongated magnetically conducting material is a straight line being at least substantially parallel to the side and positioned between 6.9 mm and 7.2 mm from the side.

3. A card according to claim 1, the card having an outer, at least substantially straight side and wherein the elongated magnetically conducting material is a straight line being at least substantially parallel to the side and positioned between 10.2 mm and 10.5 mm from the side.

4. A card according to claim 1, wherein the elongated magnetically conducting material has a magnetic conductivity of no more than 100,000 ?r.

5. A card according to claim 1, wherein the elongated magnetically conducting material has a thickness, in a direction perpendicular to the surface, of 5-200 ?m.

6. A card according to claim 1, wherein the field generator comprises a first end and a second end, the first end and the second end proximate to the first guide end and the second guide end, respectively.

7. A card according to claim 1, wherein, in a cross section perpendicular to the longitudinal direction, the field generator is positioned no more than 5 mm from the elongated magnetically conducting material.

8. A card according claim 1, wherein the field generator is elongated and has two generator ends, the card further comprising magnetically conducting elements configured to guide magnetic field from each generator end to a guide end.

9. An assembly of a card according to claim 1 and a card reader comprising a reading head configured to be positioned at, or travel a distance over, in relation to the card, the elongated magnetically conducting material of the card while sensing the magnetic field and to output a signal relating to the field sensed.

10. An assembly according to claim 9, wherein the reading head comprises at least a first field sensor having a magnetic conductivity of at least 100,000 ?r.

11. A method of assembling a card according to claim 1, the method comprising the steps of: 1) providing a card blank, 2) fixing the field generator in relation to the card blank, 3) subsequent to step 2), fixing the elongated magnetically conducting material in relation to the card blank.

12. A method according to claim 11, wherein step 3) comprises providing no electrical connection between the elongated magnetically conducting material and the field generator.

13. A method of outputting a signal from a card according to claim 1, the method comprising the step of operating the field generator to feed a magnetic field into the elongated magnetically conducting material, the elongated magnetically conducting material outputting the signal.

14. A method according to claim 13, wherein the operating step comprises operating the field generator to feed a magnetic field into the elongated magnetically conducting material, which magnetic field varies over time.

15. A method of transferring information from a card, according to claim 1, to a reading head, the method comprising: operating the field generator of the card to feed the magnetic field into the elongated magnetically conducting material, positioning a reading device in the proximity of the elongated magnetically conducting material during the operating step, so that, during the operating step, at least a part of a magnetic field transported in the elongated magnetically conducting material exits the elongated magnetically conducting material and enters the reading device, and where the reading device outputs a signal corresponding to the at least part of the magnetic field entering the reading device.

16. A method according to claim 15, wherein the positioning step comprises translating the reading device in relation to the card.

17. A method according to claim 15, wherein the operating includes feeding a field into the elongated magnetically conducting material, the field varying over time.

Description

(1) In the following, preferred embodiments of the invention will be described with reference to the drawings, wherein:

(2) FIG. 1 illustrates a credit card with a magnetic strip,

(3) FIG. 2 illustrates the standardized positions of the individual magnetic tracks of a magnetic card,

(4) FIG. 3 illustrates the relative positions of an encoder, a guide and a track position,

(5) FIG. 4 illustrates two field generators on a card, including compensating coils, and

(6) FIG. 5 illustrates a cross section of a card according to the invention.

(7) In FIG. 1, a standard credit card 10 is illustrated having a magnetic area 12 positioned in a predetermined and standardized position. The magnetic area 12 typically comprises two individual strips or signal tracks, 121 and 122, of magnetically encoded information. The positions of these strips or tracks, 121 and 122 also are standardized.

(8) According to ISO/IEC 7811-2:2001, the track 121, positioned the closest to the nearest longitudinal side 16 of the card 10 (see FIG. 2), has an edge closest to the side 16 of no more than 0.228 (5.79 mm). The boundary between the first and second tracks 121/122 is between 0.328 (8.33 mm) and 0.358 (9.09 mm) from the edge 16. The second track 122 extends to between 0.458 (11.63 mm) and 0.498 (12.65 mm) from the edge 16. A minimum track width is 0.100 (2.45 mm).

(9) Different sources identify slightly different centre distances from the edge 16 to a centre of the tracks 121 and 122, but the following distances are seen: distance from edge 16 to centre of track 121: (0.228+0.328)/2=0.278 (7.06 mm), distance from edge 16 to centre of track 122: (0.358+0.458)/2=0.408 (10.36 mm).

(10) Naturally, the tracks 121/122 may be positioned along any curves on the card. The straight lines are preferred as they facilitate a linear swipe or translation of the card in relation to the reader.

(11) The preferred embodiments of the card of the invention have one or more magnetic encoders positioned at or near the track positions of the card. These encoders are able to generate a magnetic field emulating that of a legacy magnetic strip of a card translated in relation to a reader.

(12) In FIG. 3, an encoder strategy is seen wherein a single encoder 20 is provided having a field generating element 21 comprising a coil 22 and a core 24, if desired, extending along, preferably parallel to, a curve 121 which is at one of the standardized positions of a magnetic track of a credit card. In addition, the encoder comprises a field guide 26 positioned at or below the curve position.

(13) The ends 20 and 20 of the coil 22 or core 24, which ever extends the farthest to the right and to the left, defines end points at which a large part of a generated magnetic field is output and which will travel to the other end point in a manner defined by the card characteristics and the surroundings of the card 10.

(14) The distance, D, between the ends 20 and 20 of the encoder 20 and the curve 121 and guide 26 is not critical, as the guide 26 will be selected by the field lines of the magnetic field due to its conduction characteristicsespecially if or when no other magnetically conducting elements generally directed from the first end to the second end are provided.

(15) It is noted that the main field emitted by the encoder 20 is output by the ends 20 and 20. Thus, when the positions of the ends 20 and 20 are fixed, any shape may, in principle, be used for the remainder of the encoder 20. An alternative to the straight encoder 20 of FIG. 3 is a bent or curved encoder, such as an encoder forming part of a circle, an oval or the like.

(16) However, it has been found that the coil 22/core 24 do, in fact, also output a field between the ends. This effect may be utilized by varying the distance, along the longitudinal direction, between the coil 22/core 24 and the guide 26 to e.g. obtain that the same field strength travels inside the guide 26 along its length or that the same field strength is sensed by a reading head (see below) along the length of the guide 26. In this situation, the distance D would usually increase closer to the centre of the guide 26. Alternatively, it may be desired that the guide 26 and coil 22/core 24 are parallel, such as straight.

(17) The operation of the encoder 20 is that a signal, corresponding to the magnetic field to be sensed by the reading head of a reader, which reading head is stationary over or travels along or over the field guide 26, is transmitted into the coil 22. As a result thereof, the coil 22 and core 24 outputs an magnetic field which travels into the field guide 26, via the ends thereof, to complete the unbroken field lines of the field. The field fed into the guide 26 is received both from the end portions of the core 22/coil 24 but also from positions along the length thereof (between the ends), depending on the distance between the coil 22/core 24 and the guide 26 along the length thereof.

(18) When a reader head travels along the field guide 26, or is stationary in relation thereto, field lines within the field guide will choose to enter the reader head and thus feed part of the field into the reader head and thus transfer the information, while emulating the behaviour of a standard magnetic strip of a credit card.

(19) The advantage of using the guide 26, compared to positioning the coil 22/core 24 at the curve, is that the magnetic field exiting the guide 26 and entering a reading head enters the reading head in the same manner, such as under the same angles, as those of the old-fashioned magnetic stripe cards. Thus, the field lines entering the reading head are suitably aligned compared to the coils in the reading head.

(20) The width of the guide 26, perpendicular to the longitudinal direction thereof and parallel to the plane of the card surface may be 2.5 mm.

(21) In FIG. 4, an encoder scheme is illustrated comprising, in addition to the encoder 20, a second encoder 30 as well as compensating elements to be described in further detail.

(22) For illustrative purposes, the encoders 20 and 30 are different. A large variation in encoder schemes, as will also be described further below, may be used. Usually, identical encoder types are used in the same card.

(23) The encoder 20, as in FIG. 3, comprises a field generating element 21 comprising an oblong core material 24 and a coil 22 wound around the core material 24. Parallel to the field generating element 21, a magnetic field guide 26, comprising a magnetically conductive material, is provided. The field guide 26 is provided at or along one of the standardized positions, 121, of the magnetic tracks of credit cards.

(24) The encoder 30 comprises a field generating element 31 with a core 34, a coil 32 and a field guide 36 positioned at another of the standardized positions, 122, of magnetic tracks of credit cards. The encoder 30, however, also has guides 38 configured to guide magnetic field from the coil 32 and core 34 to the guide 36 in order to increase the coupling there between and reduce a loss of field to the surroundings.

(25) In addition to the encoders 20/30, cross talk reducing coils 29/39, which may have cores or not, may be provided in order to prevent cross talk from one encoder to the other when operated simultaneously.

(26) The function of the cross talk reducing coil 29 is to create an magnetic field at the guide 36 to counter the field created at the guide by the encoder 20 at the guide 36 when operating to generate the desired field at or in the guide 26. Thus, it is desired that the resulting field from the encoder 20 and the cross talk reducing coil 29, at the guide 36, is zero or as low as feasible.

(27) The operation of the cross talk reducing coil 39 is similar.

(28) An alternative to the operation of the cross talk reducing coils 29/39 is the subtraction, in the signal fed to the encoder 20, for example, of a signal correlated to that fed to the encoder 30 in order for the encoder 20 to, itself, output a field counter acting that of the encoder 30 at the position 121 or guide 26. Other solutions will be the subtraction of the cross talk signal in the reader if desired, as both the signal from the encoder 20 and that of the encoder 30 may be sensed by the reader.

(29) In FIG. 5, a card 10 is illustrated in a cross section perpendicular to the coils, cores and guides. Illustrated is also electronics 48 for feeding electrical signals into the coils. The cross talk reducing coils 29/39 are not illustrated but may be provided or not. These usually are also fed by the electronics 48, but this is not a requirement.

(30) Also illustrated is a reading head 50 comprising two reading coils 52 and 54 each positioned so as to travel along the tracks 121/122 and thus guides 26/36 while individually receiving the fields output by the guides 26/36, respectively. Usually, the reading coils 52/54 are positioned directly above (perpendicularly to the upper surface of the card) the guides 26/36 and/or the track positions 121/122. As mentioned above, the coils 52/54 may move along the curves or guides 26/36 or remain stationary in relation to the card 10.

(31) The operation thus is as described above: the field generated by the generators is fed into the guides and from the guides, part of the field transported therein will enter the head 50 and thus the coils 52/54 positioned directly above and in close proximity to the guides.

(32) Assembly of the card 10 may be performed by providing a base element 46 which may have an indentation or cut-out portion 46 into which a pre-assembled electronic package comprising the electronics 48, coils, cores and connecting wires may be provided. This package may comprise additional elements, such as a battery, a biometric reader, such as a finger print reader, one or more displays, one or more transmitters/transceivers, such as wireless transmitters/transceivers, such as a Bluetooth transceiver, a Wi-Fi transceiver, an RF transceiver or the like, antennas, a keyboard, one or more switches, such as blister switches or piezo based switches (see e.g. WO2008/104567) or the like.

(33) The cut-away portion 46 and/or electronics may be covered by a layer 44. The guides 26/36 may be provided either individually or as a part of the layer 44 or a next layer 42. On top of the guides 26/36, a final layer 40 may be provided if desired.

(34) It may be found advantageous to have the guides 36/26 form part of the outer, upper surface of the card in order for the card reader coils 52/54 to contact or be very close to the guides 26/36. The upper layer 40 may, on the other hand, be provided in order to protect the guides 26/36 from wear, oxidation and other types of degradation. Preferably, the upper layer 40 is rather thin, such as below 100 ?m, such as below 50 ?m and has a constant thickness along the direction of the guides 26/36.

(35) It is noted that no electrical connections are required between the guides 26/36 and the coils 52/54 so that the assembly of the card may be quite simple, such as a standard lamination.

(36) Naturally, the magnetic properties of the individual parts of the encoder should support the above functionality.

(37) Thus, the coil of the encoder may be a single coil or a plurality of coils positioned along the elongated encoder, preferably with longitudinal axes along the encoder direction. The coil(s) may have the same or a varying pitch over the length. A varying pitch may be used for controlling the strength of a field output at the windings, i.e. between the ends.

(38) A single coil of 1-10 mH is presently preferred.

(39) It is noted, as mentioned above, that the coil may be bent so as to adapt the strength of transferred field along the length thereof to the guide.

(40) The core may be one or more cores. Preferably, the core(s) is/are able to carry a large field strength without the material saturating. Different materials have different B-H curves describing the flux density as a function of magnetic field strength. A material with a straight B-H curve may be the VC6025Z (from www.VacuumSchmelze.de) which has a rather sharp saturation corner, whereas mu-metal has a much softer characteristic. In the latter situation, the field strength may be kept sufficiently low for it to be in a linear area, or a compensation may be made either in the signal or in the detection.

(41) Preferably, the permeability of the core material is 100-100,000 ?r, such as 5,000-15,000 ?r, such as around 10,000 ?r. pr being the permeability relative to that of vacuum, ?0.

(42) The sharper corner of the VC6025Z material will cause a higher distortion in case of saturation but may carry more field strength before distorting the output field

(43) The magnetic properties of the guide 26/36 preferably are slightly different from those of the core, as it is desired that part of the field lines actually exit the guide when the reading head approaches. Thus, the magnetic properties of the guide should be sufficiently good for the field lines to enter the guide at the ends of the encoder. On the other hand, the magnetic properties should be sufficiently low to have some of the field lines exit the guide and enter the reading head when approaching.

(44) Thus, the permeability preferably is much higher than air and the bulk material of the card (such as plastics or polymers) and preferably lower than those of typical reading heads. Many reading heads have a permeability in the order of 300,000 ?r.

(45) Preferably, the guide has a permeability lower than that of the core (if provided at all), such as 100-10,000?r, preferably 800-5,000 ?r, such as around 1600 ?r.

(46) In this context, also the cross sectional dimensions of the guide(s) is of relevance, as the field lines travelling at the bottom of a relatively thick (in the direction perpendicular to the card surface) guide may not experience the effect of the reading head, whereby only a portion of the field lines in the guide will take part in the transfer of information.

(47) The guide may have a wide variety of thicknesses. Generally, the lower the thickness, the higher is the permeability desired to still be able to attract and carry a sufficient field.

(48) With a permeability around 1600 ?r, a thickness of about 18 ?m is suitable.

(49) Naturally, the distance from the guide to the reading head is also of relevance. Preferably, the reading head is as close to the guides as possible. It may not be desired that the reading head touches the magnetically conducting material, such as during a translation, though. A distance of 0-500 ?m, such as 5-50 ?m, is desired, such as if provided through an upper layer of a material, so that the head may touch the card during translation.

(50) In order for the guide to collect the magnetic field, it is desired that there are no other or better alternatives for the field in the vicinity of the field generator. Thus, preferably, apart from the coil(s), the core(s) and the guide, no other elements with a ?r>100, such as a ?r>10, are present in the card within 10 mm, such as within 5 mm, such as within 3 mm, such as within 2 mm, such as within 1 mm of a longitudinal or central axis of the coil(s) or the curve.

(51) Also, it may be desired to alter a depth of the guide (distance from the surface to the guide) along its length in order to adapt a field strength transferred to a reading head travelling over the surface with a fixed distance to the surface. Thus, in one embodiment, the depth of the guide may be higher at a centre thereof than at the ends thereof.

(52) The magnetic properties of the guide may be tailor-made if desired. For example, it may be preferred to provide a guide with different magnetic properties in different directions. For example, it may be desired to have a higher pr in a direction toward the surface or reading head than along the longitudinal direction of the guide. In this manner, field lines travelling far from the surface will see a lower pr when travelling up through the guide material and into the reading head, so that thicker guide materials may be used.

(53) The guide material may be a metal. The guide material may be a monolithic material, such as a foil or tape. Alternatively, the guide material may be a powder moulded or otherwise provided into a carrier material, such as plastics, polymers or the like. The guide material may form part of a plastic sheet provided on the card. This may be obtained using co-extrusion, embedding, moulding or the like.