FR2711438A1 - Unfalsifiable data support - Google Patents

Abstract

Unfalsifiable data support comprising a substrate on which are inscribed at least one first and one second overlapping image bearing data and a lenticular lattice at least partially covering the substrate and having a pitch nominally equal to the pitch of overlap of the images, the said data including information data to be protected and verification data, characterized in that: - a so-called first image includes the information data which are inscribed on at least one background region consisting of a first flat tint of a first non-white colour; - a so-called second image includes the verification data which consist of at least one verification region consisting of a second flat tint of a second non-white colour, different from the first colour, the said background region and the said verification region themselves overlapping.

Description

INFALSIFIABLE DATA SUPPORT
The subject of the present invention is a tamper-proof data medium comprising a substrate on which are written at least first and second nested images carrying data and a lenticular network at least partially covering the substrate and having a pitch nominally equal to the pitch of nesting of images, said data comprising information data to be protected and verification data.

 Such a data carrier is known in particular in the form of an identity card from European patent application EP 323 108 (NIMSLO) according to which three nested tapes form as many images which are written on a photographic emulsion through the lenticular system and, for a much longer time in the field of self stereoscopic relief photography.

 The different images are successively visible and invisible according to the angle of vision with respect to an axis of rotation parallel to the axis of the lenses of the lenticular network.

 One of the images contains data which distinguishes the card from other similar cards, the other images containing patterns, some of which can be seen from all angles, for example a bar code, or only from certain angles.

 The security of the card is ensured by the presence of the lenticular network and by the presence of selective visibility of the verification data identifying the user.

 Although such a card has a significant level of security, it is however possible to falsify it, in particular by truncating or adding information without this appearing.

a plurality of information capable of being read from different angles is recorded using a network of lenses using a laser beam in which security is improved using a guilloche model.

 German patent application DE 3 425 261 (SCHILLER UNIVERSITE TAT) proposed the recording of information using a laser in the volume of a material, so as to improve safety by the presence of a structure of images which is by itself three dimensional.

German patent DE AS 2 155 214 (LANDIS &
GYR) proposed a support having a relief structure, having optical markings and having details of the same order of magnitude as the wavelength of visible light, which makes it possible to give the document specific properties making it difficult to possibly falsification.

 French patent application FR 2 456 625 (JOLY) relates to a process for producing an image on a support which is secured by the use of a reading frame on one side of the support and, on the other side of the support. , a raster image or raster image.

 PCT patent application WO 82/04132 (POLAROID) relates to a verification system in which optical effects are observed presented by patterns of rows of regularly positioned lenticles and of colored lines which correspond to them and which are displayed on a background of lenticles positioned regularly and corresponding colored lines. This technique requires two lenticular networks which correspond.

United States patent US 4,417,784 (RCA
CORPORATION) relates to an information verification device having a relief reflecting structure (lenticular network), each lens of which comprises a series of juxtaposed elements which have different reflection characteristics.

 European patent application OP 105 099 (LANDIS & GYR) relates to a device for securing a document and which includes a color model whose displacement creates a well-defined and verifiable visual effect.

 European patent application OP 216 947 (MAURER ELECTRONICS GmbH) relates to a secure card according to which cylindrical lenses separated from one another make it possible to separate an image into several zones, one of which, located directly above the lens, is concentrated and is darker than the other adjacent areas. In addition, an unimpressed area separates the concentrated area from the adjacent areas.

 Most of the aforementioned devices are characterized by a fairly great complexity of design and / or production without however providing absolute security. In particular, the presence of so-called complicated verification reasons is such as to only recognize the falsification of a document by specialists.

Other systems, if they are safe from forgery, entail a complication which makes their costs incompatible with wide circulation.

 The subject of the present invention is therefore a tamper-proof data carrier which does not have the aforementioned drawbacks and which, in particular, is simple in design and allows easy testing of any falsification of the document.

The invention thus relates to a tamper-proof data medium comprising a substrate on which are written at least first and second nested images carrying data and a lenticular network at least partially covering the substrate and having a pitch nominally equal to the nesting pitch. images (or a multiple thereof), said data comprising information data to be protected and verification data characterized in that
a so-called first image comprises the information data, which is written on at least one background region consisting of a first solid of a first non-white color
a said second image comprises the verification data, which consist of at least one verification region consisting of a second solid of a second non-white color, different from the first color, said background region and said verification region being themselves - same nested.

 According to an advantageous variant, the data medium comprises several separate background regions and an equal number of verification regions.

 The first and second colors can be complementary colors, for example green and red. These colors being very different from each other, the identification of a possible falsification is made even more obvious.

 The nesting pitch of the images is preferably substantially equal to 50 microns, a value corresponding on the one hand to a pitch of the lenticular network which can be easily achievable in practice, and on the other hand to difficult falsification.

 Said data may also include unprotected information data, for example standard data (NAME, FIRST NAME, ADDRESS, etc.) such as that found for example on identity cards.

According to a preferred embodiment, the data medium comprises a color photographic layer coated on a flat face with a lenticular network and said data are recorded photographically.

 The invention also relates to a method for manufacturing a data carrier as defined above, characterized in that it comprises the following steps a) advancing a roll of data carriers by a determined quantity, said determined quantity being nominally equal to one dimension of an individual data carrier, b) successively overlay a first image and a second nested image, c) cut the individual data carriers, d) repeat the operations a) ac) for each individual data carrier.

 These data carriers may include a color photographic film coated on a flat face with a lenticular network. The method can then include the following steps e) after step b), developing and drying the film photographically impressed during step b).

Other characteristics and advantages will appear better on reading the description which follows, given by way of nonlimiting example, in conjunction with the drawings which represent
FIG. 1: the first and second images as well as an identity document comprising it,
FIG. 2: a detail of a data carrier according to a preferred embodiment of the invention,
FIG. 3: a preferred embodiment of an installation for implementing the method according to the invention,
- Figure 4: a device for implementing the method according to the invention.

In FIG. 1, a first image 1 comprises information data inscribed on a printed background consisting of a first solid of a first color different from white. This information data is, in this case, constituted by standard data such as 11 (NAME, FIRST NAME), 12 (ADDRESS DELIVERED BY, SIGNATURE) and personalized data specific to each data medium, namely the NAME of the card holder 14, the FIRST NAME 15 of the card holder, their ADDRESS 16, the NAME 16 "of the authority that issued the card, the
NUMBER 17 of the card and, finally, the SIGNATURE 18 affixed to it by the card holder whose PHOTOGRAPHY 19 is affixed to it.

 The second image comprises, in the example illustrated in the figure, the same standard data 11, 12 of image 1 and a certain number of areas 24, 25, 26, 26 ', 27, 28 and 29 which are produced in a second non-white color different from the first color and which corresponds respectively to data 14, 15, 16, 16 ', 17, 18 and 19.

 Images 1 and 2 are nested on a card support 3 on which a lenticular network 32 has been added, the axis of the individual lenses of which is parallel to the upper edge 6 of the card.

 As shown in the box in FIG. 1, images 1 and 2 are nested together at a step equal or multiple to that of the lenticular network: for example we have shown for each lens 33 of the lenticular network 32 an overlapping of two images 1 and two images 2 each of which occupies 50% of the surface, which corresponds to equal viewing angles for the two images. This equality ratio can be modified for example to increase the visibility angle of the image 1. The first and second colors must have a good contrast with the color in which the information is written (generally black) .

 When he looks at the map from different angles, that is to say by rotating it under an axis parallel to its upper edge 6, the observer alternately sees images 1 and 2, that is to say either standard information and identity information relating to the card holder, ie image 2 containing the standard information and verification information 24 to 29 in the form of a solid of the second color.

 It will be understood that this allows easy verification of a possible falsification of the card.

 For this purpose, reference is made to FIG. 2, which shows an enlarged detail of a card according to the invention in which the image 1 and 2 are in an area containing protected information.

In such areas, the card appears in alternation of red lines R corresponding to the verification ranges 24, 25, 26, 26 ', 27, 28 and 29 (image 2) and green lines corresponding to the protected data 14, 15 , 16, 16 ', 17, 18 and 19 (image 1)
In FIG. 2, the information data have been represented in the form of black areas 30 which are all, of course, located in the green lines.

If we now imagine that a falsifier would have wanted to delete or add information 30 after the card was made, we can notice that
- in the first case, consisting of a deletion of information, any erasure of a range 30 results in the presence of a white or discolored area and, in any case, having a color different from the original green color in green lines.

 - in the case of adding information, it will be noted that any addition of information extending even very slightly beyond the corresponding green line, will be very easily noticed on the red background which is itself strongly contrasted with respect to green and compared to black areas 30.

 It will therefore be understood that the advantage of the invention in the simplicity of the detection of a falsification since, the principle which is implemented is that slight variations in an area of a solid color are very easily noticed.

 This inventive method is therefore very clearly distinguished from those of the prior art in which there were very complicated and difficult to reproduce patterns to provide protection against falsification.

 Furthermore, it will be noted that, if a falsifier wants to try to repair a badly repaired falsification, he will have to find exactly the same shade of color in the solid region, which is very difficult in practice.

 In addition, the use of complementary colors for the solid areas of images 1 and 2 make the detection of forgery even easier, since such colors are highly contrasted with one another.

 FIG. 3 represents a preferred device for implementing the method of its invention.

Image 1 is carried by a support 44 capable of rotating around an axis O1 perpendicular to the plane of the figure and Image 2 is carried by a support 45 capable of rotating around an axis O2 perpendicular to the plane of the figure. The support 45 is arranged on the optical axis so that the axis O2 intercepts the latter, which means that the image 2 can be printed directly on a support 31 covered with a lenticular network 32 while the support 44 sees its image reflected by a mirror 46 movable around an axis O3 perpendicular to the plane of the figure and offset from the optical axis of the lens L. I1 is movable between two positions: that shown in solid lines which makes it possible to return the image 44 through the lens L and a second position shown in dotted lines in which the image 2 is sent directly by the lens L.

 The support 31 covered with a lenticular network 32 is a film carried by a reel 41 deposited in a housing 40 and produced in the form of a continuous strip and returned by a return element 42 and then passes through a development tank 50 (MINILAB) then by a drying installation 51 and a cutting installation 52 to give the individual supports 3. The rotation of the support 44 and 45 takes place at angles B and C of equal value corresponding to the desired viewing angles. This technique is analogous to that used in devices for producing stereoscopic images.

 Figure 4 is a variant of Figure 3 in which the support is made by translation.

 I1 presents an optical device Ol comprising an image sharing device (such as 44,45,46), a lens L 'movable in translation and a support 62 also movable in translation, and having a back to block a region of a film while shooting a map.

The displacement of the lens L ′ and of the support 62 on which the region of the roller 41 to be impressed is placed is such that the optical axis is preserved, ie a displacement proportional to the distance to the image plane of the device 61. This technique is also analogous to that used for producing stereoscopic images. The translatable support 62 is integrated in a housing such as 40 with sufficient length of the film (31,32).

Claims (2)

 1 tamper-proof data medium comprising a substrate on which are written at least first and second nested images carrying data and a lenticular network at least partially covering the substrate and having a pitch nominally equal to the nesting pitch of the images, said data comprising information data to be protected and verification data characterized in that - a said first image comprises the information data, which are written on at least one background region consisting of a first solid of a first color not white - a said second image includes the verification data, which consists of at least one verification region consisting of a second solid of a second non-white color, different from the first color, said background region and said verification region being themselves nested.  2 "Data carrier according to claim 1, characterized in that it comprises several bottom regions separated from each other and an equal number of verification regions.  3O data carrier according to one of claims 1 or 2, characterized in that the first and second colors are complementary colors.  4 "Data carrier according to claim 3, characterized in that said complementary colors are green and red.  5O data carrier according to one of the preceding claims, characterized in that the nesting pitch of the images is substantially equal to 50 microns.  6 "Data carrier according to one of the preceding claims, characterized in that said data also include unprotected information data.  7 "Data carrier according to one of the preceding claims characterized in that it comprises a color photographic layer coated on a flat face with a lenticular network and in that said data are recorded photographically.  8 Data carrier according to one of the preceding claims in that it constitutes an identity document.  9 "A method of manufacturing a data carrier as defined in any one of the preceding claims, characterized in that it comprises the following steps a) advancing a roll of data carriers by a determined quantity, said determined quantity being nominally equal to one dimension of an individual data carrier, b) successively embedding a first nested image and a second image, c) cutting the individual data carriers, d) repeating the operations a) to c) for each data carrier individual.  10 Data carrier according to claim 9, characterized in that the data carriers comprise a color photographic film coated on a flat face of a lenticular network and in that it comprises the following steps e) after step b) , develop and dry the film impressed photographically during step b).