HK21292A

HK21292A - Card-shaped data carrier and method of producing it

Info

Publication number: HK21292A
Application number: HK212/92A
Authority: HK
Inventors: Thomas Maurer
Original assignee: Maurer Electronics Gmbh
Priority date: 1985-10-01
Filing date: 1992-03-19
Publication date: 1992-03-27
Also published as: AU600922B2; EP0216947B1; ATE59717T1; EP0216947A1; AU6698386A; DE3581082D1; SG16892G

Abstract

Card-shaped data carrier with a substrate and at least one transparent cover foil, which substrate is provided with information items which are recognisable through the cover foil by using a laser beam through the cover foil, the transparent cover foil (2) carrying a relief (3) which has been applied before the recording of the information items and which at least partially overlaps the information area, which relief characteristically changes the information recording due to its optical lens effect, and method for fabricating it. <IMAGE>

Description

The subject of the invention is a map-shaped, relief-bearing data carrier as described in the heading of the main claim 1 and a process for its manufacture.

The data carriers for visually readable data, such as those used for credit cards, identity cards and similar applications, will be provided with a transparent cover, such as a transparent cover made of polyvinyl chloride or polyester, to protect the data stored, in order to prevent the data recorded on the data carrier (text, images, logos, patterns, markings and the like) from becoming illegible or unrecognizable by contamination or alteration in normal use, and to ensure that the data can be easily and with minimal effort enlarged or altered.

To prevent or prevent counterfeiting, the information carrier can be protected by various measures using techniques known to be used in the printing of paper or banknotes, for example the form of a laminated identity card, the card inlet of which consists of watermark paper, which may be printed with so-called guilloches in several colours, as is known for example for cheque cards.

DE-B-3 248 748 describes an identity card with alphanumeric characters, which are available in high-pressure form, suitable for use as a printing plate.

In accordance with GB-A-2 132 136, which also describes an identification card, there is also a cover film on the substrate.

The FR-A-2 450 164 also contains an identity card with a light-sensitive layer and a transparent cover layer above it, where the transparent cover film also serves to increase the displayed representations of the safety print.

Finally, DE-PS 29 070 004 provides for a further development in the form of an identity card consisting of two cover films, at least one of which is transparent, and a card insert made of a light-transmitting material, in particular paper, bearing visually identifiable information, which has been applied through the transparent cover film to the insert by means of a laser beam.

However, falsification or falsification cannot be excluded here either; in order to further improve the safety of falsification, the present state of the art also specifies that, depending on the energy dosage of the laser beam used to record the information, the upper cover film can be melted down to form a cover-like relief over the linear line of the information which can be felt manually.

The Commission has already made a number of proposals to the Council and the Council on the subject of the use of the information system for the identification of persons, in particular by means of the use of the Internet, and the use of the Internet for the identification of persons, in particular by the use of the Internet.

The present invention is therefore intended to further improve the security of counterfeiting of card-shaped data media of the type indicated at the outset.

This problem is now solved by the characteristics of the card-shaped data carrier as described in main claim 1.

The object of the invention is therefore a map-shaped, relief-bearing data carrier with a substrate and at least one transparent cover film, which substrate is covered by a laser beam through the cover film with information discernible through the cover film, characterized by the fact that the transparent cover film bears the information area at least partially overlapping relief placed before recording the information, which has an optical lens effect and thus characteristically modifies the information to be recorded using the laser beam.

The subclaims concern preferred embodiments of the subject matter of the invention.

The invention also relates to a method for the manufacture of the data carrier according to the invention, characterized by covering a transparent cover film with a relief having an optical lens effect on the substrate by engraving a negative relief pattern on a cashmere plate or, after covering a negative relief pattern, by rendering the cover film with the optical lens effect by using these imprints and then, through the cover film, at least partially recording the information on the substrate by means of a laser beam in the area below the relief.

The invention prevents the attempts to falsify mentioned above by the addition of a relief to the transparent cover film and thus to the surface of the card, on a suitable frame, namely in the area of the card in which essential information, e.g. a photograph of the cardholder, is to be recorded later by means of a laser beam, in the form of a raised line or point pattern, namely in the form of convex lines or points, which thus form an optical lens system on the surface of the cover film of the card-shaped carrier, which, when recorded later by means of a laser beam, produces a laser beam in a manner which does not obstruct the transmission of this information - and which is necessary in the course of the work - in such a way that the information obtained by the laser beam is transmitted in a manner which is not necessarily reflected by the material - and thus the material is not subject to any change in the material.

This modification of the information recorded by the laser beam on the substrate remains visible even if, for example, the original relief is removed and/or replaced so that such a forgery can be detected without further delay.

The relief according to the invention, which is arranged on the transparent cover film, may be advantageously presented in the form of a raised convex line or point pattern, which may be either surface- or non-surface-covered.

A particularly preferred embodiment of the invention is to provide the surface-covered line or point pattern in the form of lines, concentric circles, a flat typeface and/or a flat logo, for example in the form of Guilloche patterns, as found on banknotes or cheque cards. It is even more preferable, however, to provide this relief in the form of a non-area-covered line or point pattern, namely in the form of letter symbols, a monogram, limited modes of a Guilloche photo pattern, a stamp, a relief pattern and/or a linear effect pattern, which is determined by the fact that the portion of the image is being drawn with a laser, which is now used to modify the image of the cardholder, such as a photo-transparent image or a photo-transparent image, which can be obtained by using a laser or a photographic substrate, which is now used to record the image of the person, such as a photo-transparent image, or a photo-transparent image, which can be recorded by means of a laser.

In order to clarify this point, the invention is explained in more detail below by reference to the accompanying drawings. Fig. 1 an enlarged partial section view of an embodiment of the card-shaped data carrier of the invention,Fig. 2 a diagram illustrating the modification of the information effect achieved according to the invention,Fig. 3 a curve representation representing the shading curve generated by the embodiment of Fig. 2 andFig. 4 a diagram illustrating the effect of the modification of the recorded information on the viewing.

As shown in Fig. 1, the card-shaped data carrier of the invention comprises a substrate 1 of a material with high absorption for the laser radiation used and may be composed, for example, of a light-transparent material such as paper, filler-containing plastic and the like or also of a transparent material having the required absorption.

On the top of deck film 2 is a relief 3, which, as can be seen from the view shown, is in the form of three cylindrical lenses.

On the substrate 1 or on the boundary between substrate 1 and cover film 2, information is recorded by means of a laser beam through the transparent cover film 2 and the relief 3 above it, which are indicated in Fig. 1 by the reference numbers 4, 5 and 6.

In Figure 2 this is shown on an even larger scale, where the arrows running vertically from top to bottom are supposed to reflect the irradiated laser beam. The laser beams are broken up by the optical lensing effect of relief 3 and collected in area 5 as shown schematically in Figure 2. In areas 6 no laser beam hits the boundary between substrate 1 and transparent sheet 2 where no relief 3 is present, no bundling of laser beams takes place, so that a slightly smaller attenuation of the substrate or of the material being irradiated at the boundary intensity and the cover sheet, a light-sensitive material, is achieved.

As can be seen from Fig. 3, this results in a characteristic modification and change in the density of the recorded information, which is due exclusively to the relief 3 on the cover film 2. Even after removal or change of the relief 3 on the surface of the cover film, this characteristic modification of the recorded information persists, so that a high degree of falsification reliability is achieved.Whereas the relief appears black when viewed at an angle of 90° according to the black arrow A, it appears brighter or even white at a different angle of observation, for example, when the angle of observation is 70° (arrow B), where the unchanged area 6 moves into the field of observation through the optical lens effect of the relief 3 and depends on the refractive index of the transparent cover film 2, the radius of curvature of the relief 3 and the thickness of the transparent cover film 2 and is readily reflected in the law of linear optics.

In the case of the practical application of this effect, for example on the card-shaped data carriers in question, the information of which is fed into the card by means of a high-power laser, a profound change (blackening) occurs on the transparent cover layer due to the special interaction with the card material, which does not, however, affect the effect described or only slightly.

The effect described above can also be achieved with card-shaped data carriers made of a transparent single-layer or multi-layer material capable of absorbing the laser radiation used to record the information to a sufficient extent and constructed in such a way that the blackout caused by the laser radiation is present within the transparent material.

The present invention thus enables, by means of the high relief 3 on the deck sheet 2 or a totally transparent data carrier, a characteristic modification of the information recorded by this relief, with the result that this information disappears on a side view due to the different blacking or nonblacking, an effect which cannot be achieved by subsequent modification of the map.

The invention also relates to a method for producing the above-mentioned card-shaped data carrier according to claim 1, which consists in applying a casing plate to the substrate (1) by engraving the desired relief pattern onto the transparent cover film (2) or, after applying the casing sheet to a flat cover film, by embossing it (3) and then recording the information on the substrate (1) by means of a laser beam through the cover film at least partially in the area below the relief.

Claims

1. Card-shaped data carrier bearing a relief with a substrate and at least one transparent covering film, the substrate being provided with information readable through the covering film by means of a laser beam which passes through the covering film, characterised in that the transparent covering film (2) bears the relief (3), which overlaps the information area at least partially and is applied before the information is recorded, this relief producing an optical lens effect and thus characteristically modifying the information that is to be recorded by means of the laser beam.

2. Card-shaped data carrier according to Claim 1, characterised in that the relief (3) is in the form of a raised pattern of lines or dots.

3. Card-shaped data carrier according to Claim 2, characterised in that the relief (3) is in the form of a raised pattern of convex lines or dots.

4. Card-shaped data carrier according to Claim 3, characterised in that the relief (3) is in the form of cylindrical lenses.

5. Card-shaped data carrier according to at least one of the foregoing Claims, characterised in that the cylindrical lenses are in the form of a pattern of lines covering the surface.

6. Card-shaped data carrier according to at least one of the foregoing Claims, characterised in that the pattern of lines or dots covering the surface is in the form of lines, concentric circles, two-dimensional lettering and/or a two-dimensional logo.

7. Card-shaped data carrier according to at least one of the foregoing Claims, characterised in that the relief (3) is in the form of a pattern of lines or dots which does not cover the surface.

8. Card-shaped data carrier according to Claim 7, characterised in that the relief (3) is in the form of letters, a monogram, an engine-turned pattern, a stamp, a national emblem or a logo made up of lines.

9. Card-shaped data carrier according to at least one of the foregoing Claims, characterised in that the information is characteristically modified by interference phenomena between the pattern of lines or dots of the relief (3) and the grid of the information recording.

10. Method for the manufacture of the card-shaped data carrier according to the foregoing claims, characterised in that a transparent covering film (2) provided with the relief (3) which has an optical lens effect is bonded on to the substrate (1) with the aid of a lining sheet provided with a negative relief pattern produced by engraving, or else after a flat covering film has been bonded on, it is provided with the relief (3) with the optical lens effect by embossing, after which the information is recorded through the covering film onto the substrate (1) at least partially in the area underneath the relief by means of a laser beam.