DE102009037832A1 - Identification document with two overlapping images - Google Patents

Abstract

The invention relates to an identification document which is provided with two superimposed images and a method for producing such an identification document. Furthermore, the invention relates to a method for checking the authenticity of such an identification document. In order to better secure such identification documents that are provided with a color image against counterfeiting or manipulation, it is proposed that the images are applied in separate work steps, that at least one of the images is in a form that is not accessible from the outside, that it is one of the images is a grayscale image and that one of the images is a color image that includes both color information and light / dark information.

Description

The invention relates to an identification document provided with two superimposed images and to a method for producing such an identification document. Moreover, the invention relates to a method for checking the authenticity of such an identification document.

Identification documents, such as identification cards or passports, or other recording media, such as bank cards or credit cards, etc. are increasingly provided with a color image, for example, with a color light image of the owner. The commonly used in practice printing method for printing color images, z. As the dye sublimation, are considered uncertain, since the dyes can be relatively easily removed because of their low penetration depth. To increase the security of the color image, a transparent laminate or varnish has been applied to the color image in the past.

Another way to increase the security of such documents is to use, in addition to the printing process, another method of applying higher security image information. Labeling with a marking laser is considered to be a safe marking method because of the possible high depth of penetration and the irreversible material change, so that color printing is combined with laser marking in practice.

Such a combination is for example from the document EP 0 537 484 A1 known. In the method described therein, a color image is divided into two parts, namely a light / dark portion and a colored portion, wherein the light / dark portion is introduced by means of a caption laser forgery-proof in an image carrier. The sub-image thus generated is then superimposed coincident with the color component, which is printed on the image carrier for this purpose. In other words, the printed color sub-image contains only color information, while the associated light / dark information is contained in the sub-image underneath. The two fields complement each other to the stored total information. The bright-dark sub-image introduced in the image carrier without forgery remains intact even if the printed color image is removed from the image carrier. An identification should then be possible solely on the basis of the remaining light / dark field.

A disadvantage of the described method, however, is that the two partial images must always be arranged exactly one above the other, so that the desired overall impression arises with a complete image information. For this purpose, either a complex coordination of the data sets for printer and laser arrangement or a no less complex assignment of the two partial images to each other is required by markings provided on the image carrier are detected by means of optical sensors. The method described is therefore comparatively complicated, especially when different printing systems have to be used and coordinated with one another.

In addition, the increase in security is limited. Since the color partial image superimposes the light / dark partial image congruently, the bright / dark partial image is not completely visible to the naked eye, so that the image information of the light / dark component can only be verified poorly. In a manipulation of the image data, it could be exploited that only a portion of the image information has been stored counterfeit-proof in the bright / dark field. Thus, it is possible to remove the color image and print with a conventional color printing system a new color image with other image information, which then superimposed on the unchanged light / dark content. Such manipulation is facilitated in identification documents with light images due to the fact that a uniform orientation of the head, the size of the image, etc. is required for photographs. Due to the high similarity of the different light images with each other, the newly applied color image can thus be aligned with the more clearly visible components of the light / dark partial image (eg eyes, nose, mouth, etc.), so that a very precise superposition of the manipulated colored partial image with the existing light / dark field is possible.

An object of the present invention is to better secure identification documents provided with a color image against forgery.

This object is achieved by an identification document according to claim 1 or a method for producing such an identification document according to claim 8.

The identification document according to the invention is characterized in that it is provided with two superimposed images, that the images are applied in separate steps, that at least one of the images is present in a form not accessible from the outside, that it is one of the images Grayscale image, and that one of the images is a color image that includes both color information and light / dark information.

The inventive method for producing an identification document, the two superimposed images is characterized in that one of the images is a grayscale image, that one of the images is a color image comprising both color information and bright / dark information, and that the Color image is printed on an image carrier and the grayscale image is introduced by means of a controlled laser beam in an image carrier.

Moreover, the above object is achieved by a method for examining such an identification document or the like according to claim 11.

The inventive method for checking the authenticity of an identification document is characterized by the steps of: irradiating the identification document or the like with a first test radiation for reading the image information of the color image, irradiating the identification document or the like with a second test radiation for reading the image information of the gray scale image, reading the Image information of the color image and the gray scale image and evaluation, in particular comparing the image information obtained.

Advantageous embodiments of the invention are specified in the subclaims.

The advantages and embodiments explained below in connection with the method also apply mutatis mutandis to the devices according to the invention and vice versa.

Under an identification document in the context of the invention not only identity cards or passports are understood, but also other recording or data carriers, such as bank or credit cards or the like, which are not or not primarily used for identification purposes. In general, this is understood to mean a document or record carrier which is provided with images which are to be protected against manipulation or forgery.

In this case, an image is understood to be an optically readable representation of information, which may in particular be photographs of persons, symbols of highness, graphical security elements, text information or other representations.

A basic idea of the invention is to pick up the technology described in the prior art and modify it such that the color image comprises complete image information, that is, both color and contrast information. So it is a key point of the invention to use just no fields. Since there are always two images, each with complete image information, these can be verified more easily, so that manipulations are easier to recognize or a forgery is significantly more difficult.

In this case, the image information from the one image may be completely or partially contained in the other image. In an advantageous embodiment of the invention, the grayscale image comprises all image information of the color image, with the exception of the color information.

If the two images are identical or the images differ only with regard to the color information, then they are advantageously arranged relative to one another such that they overlap congruently. For this purpose, both images have identical dimensions and are positioned exactly to each other. In this case, two images with maximum image information can be arranged on a carrier in a particularly space-saving manner. The color image is preferably designed so that it is visibly visible to a viewer over the underlying gray scale image in daylight. Therefore, no exact alignment of the two images is required. Moreover, a congruent overlay is also not necessary because the pictures do not have to be complete.

In an alternative embodiment of the invention, none of the pictures contains picture information of the other picture. In other words, it is also possible to provide the identification document with two different images. This possibility is not possible in the solution known from the prior art, in which the image information of the two partial images must first be added to produce the overall image.

An embodiment of the invention has proved to be particularly advantageous in which the color image is permeable to a test radiation with which the gray scale image is irradiated for test purposes. This ensures that a reading of the full image information of the gray scale image is not hindered by the color image. This allows a particularly simple check of the authenticity of the identification document.

If the color image is printed with a printer on an image carrier and the grayscale image introduced by means of a controlled laser beam in an image carrier, the application of the images is thus in other words in separate steps, then such printing and labeling methods can be used, already in practice are tested. Thus, the present invention can be used substantially with existing machines be realized without major Umrüstkosten arise.

Preferably, it is the grayscale image that is generated in a form not accessible from the outside. Particularly suitable for this purpose is the use of a controlled laser beam, which inscribes the grayscale image in the image carrier. A grayscale image is understood to be an image that includes light / dark information. The number of grayscale plays only a minor role for the invention; In principle, therefore, the grayscale image can also be a black and white image.

As the image carrier is, for example, a transparent film, as it is used as one of the outer layers of a plastic identification document. When the transparent film is used as a common carrier for the color image and the gray scale image, the color image is printed on the transparent film. The grayscale image is burned into the film using the laser beam. Preferably, to protect the color image on the transparent film, a further protective layer, such as a laminate or lacquer layer, attached.

If the ink used for the color image is transparent to the test radiation used to irradiate the grayscale image and a label laser emitting in the same wavelength range is used, the order of "printing processes" is arbitrary. In other words, either the color image first or the grayscale image first can be produced. The visual impression of the visible color image is the same in both processes.

In a further embodiment of the invention, different image carriers are used for the color image and the gray scale image. For example, if the identification document is layered, as is often the case with laminated cards, different layers of the card serve as image carriers for the color and grayscale images, respectively.

The image carrier for the color and grayscale image may be an intermediate in the manufacturing process of the security document. Thus, for example, the film image carrier can be arranged on a carrier substrate that serves as part of a layer structure of an identification card. However, the image carrier may already be a finished end product.

When checking the authenticity of the identification document, it is irradiated with a first and a second test radiation, wherein the first test radiation is used to read the image information of the color image and the second test radiation is used to read the image information of the gray scale image. Subsequently, the image information obtained is compared, wherein all the above-mentioned method steps, but in particular the comparison step in the corresponding test apparatus can be automated.

Since the color image for the test radiation, with which the grayscale image is irradiated for testing purposes, is transparent, it can not be detected when using such a test radiation. In other words, reading the image information of the color image using this test radiation is not possible. The grayscale image, on the other hand, is completely readable in this case. Thus it can be checked whether the color image has actually been applied with such printing inks that are permeable to the test radiation. If false inks are used, the color image overlaps the underlying grayscale image and reading of the full image information of the grayscale image is excluded. In other words, it is possible to fully visualize the gray scale image covered by the color image with the aid of the inspection radiation, without the color image covering image information of the gray scale image.

In the test radiation, with which the gray scale image is irradiated for testing purposes, it is preferably infrared radiation, which with an infrared illumination and an infrared-sensitive detector, for. As a CCD sensor that can be used in video or video cameras are detected. Alternatively, test radiations with other wavelengths or wavelength ranges may be used. The prerequisite for this is that the working environment is adapted accordingly. In particular, materials suitable for the test radiation, in particular for the inks of the color image and the image carriers, must be used and suitable sensors for checking the image information must be available.

In the test radiation, with which the color image is irradiated for testing purposes, it is preferably visible to the human eye light, z. B. Daylight. Upon irradiation of the identification document with daylight, essentially only the color image is visible to a viewer.

Preferably, a detector that is sensitive to both visible and infrared light is used in conjunction with a light source that emits visible light along with infrared light. This can be both artificial light and sunlight. In this case, the color image and, if not covered by the color image, the gray scale image can be detected at the same time.

If a filter is placed in front of this detector, which transmits only infrared light, then the gray scale image can be detected, since the color image for the infrared light is transparent.

Alternatively, the image carrier may optionally be illuminated with visible light and infrared light.

The image information of the two images thus detected can be compared with one another following the illumination and acquisition of the image information.

Tampering or counterfeiting can then be detected when either the color image is visible under the infrared light or the grayscale image is not visible under the infrared light or under visible light or the grayscale image and the color image do not contain the expected information.

Embodiments of the invention are explained below with reference to the drawings. Hereby show:

1 a schematic representation of an identification document with a transparent film as an image carrier (sectional view),

2 a schematic representation of an identification document with two different image carriers (sectional view),

3 a schematic representation of a first example identification document in daylight ( 3a ) and IR light ( 3b )

4 a schematic representation of a second example identification document in daylight ( 4a ) and IR light ( 4b )

5 a schematic representation of a third example identification document in daylight ( 5a ) and IR light ( 5b ) and

6 a schematic representation of a fourth example identification document in daylight ( 6a ) and IR light ( 6b ).

All figures show the invention only schematically and with its essential components. The same reference numerals correspond to elements of the same or comparable function.

On the schematic representation of the printer or the printing method for printing the color image and the schematic representation of the laser assembly and the method for driving the laser beam on the one hand and the schematic representation of the test method or the test device is omitted, since this information is either familiar to the expert or in sufficient clarity from the description below.

A schematic representation of an identification document in the form of an identity card 1 is in 1 displayed. The ID card 1 comprises a polymer carrier 2 and serving as a cover layer, on the support 2 arranged transparent plastic film 3 as image carrier for two superimposed images.

The two pictures are in separate steps on the slide 3 applied or in the film 3 brought in. It is on the one hand on the surface 4 the foil 3 printed color picture 5 and on the other hand, one in the film 3 branded grayscale image 6 , which thus exists in a form not accessible from the outside. The color image is superimposed 5 and the grayscale image 6 ,

The color image 5 is applied using a dye-sublimation printer. The introduction of the grayscale image 6 takes place with the aid of a (near) infrared laser beam operating at a wavelength of 1064 nm, which irreversibly discolors the processed material starting from the surface in the interior by means of local combustion or sooting and thus prevents forgery.

The color image 5 is characterized in that it includes both color information and light / dark information. The underlying grayscale image 6 includes all image information of the color image 5 with the exception of the color information. To generate the grayscale image 6 is preferably the color image 5 in a grayscale picture 6 so that all picture information except the color information is preserved.

In 2 is another identification document, also in the form of an identity card 1 represented. Different layers are used for the construction of the identification card 1 as a picture carrier. The color image 5 is on an upper layer 7 imprinted while the grayscale image 6 with a controlled laser beam in an underlying, directly to the upper layer 7 adjacent lower layer 8th is introduced. An exact assignment of the two layers 7 . 8th each other such that the color image 5 and the grayscale image 6 are arranged congruent to each other, is not mandatory, since each image already contains a complete image information and an exact synopsis of the two images is not required.

To protect the color image 5 is in both cases above the image carrier of the color image one protective layer 17 provided in the form of a transparent laminate.

In both cases, this is the color image 5 permeable to infrared radiation used as test radiation for irradiating the grayscale image 6 serves.

When checking the authenticity of the ID card 1 the card is irradiated 1 with daylight for reading the image information of the color image 5 and infrared light irradiation for reading the image information of the gray scale image 6 , At the same time, the image information of the color image becomes 5 and the grayscale image 6 read with the aid of suitable sensors and fed to an evaluation unit for evaluating, in particular for comparing the obtained image information.

This in 3 illustrated first example identification document 9 is with a color picture 10 , namely the photograph of a woman. This image information is visible in daylight, as in 3a shown. Irradiated this document 9 with infrared light, you get the in 3b illustrated grayscale image 11 which contains the same image information as the color image except for the color information 10 , In an evaluation of the read image information, here in particular in the form of a comparison of the image information of the color image 10 with the image information of the grayscale image 11 is done, this match is detected. There is no forgery or manipulation of the color image 10 in front.

This in 4 illustrated second example identification document 12 is again provided with the colored photograph of a woman. This image information is visible in daylight, as in 4a shown. If you irradiate this document with infrared light, you get the in 4b illustrated grayscale image 13 representing a photograph of a man. An evaluation of the read image information shows that the image information does not match. The document 12 belongs to a male person. The color image 10 was forged.

This in 5 illustrated third example identification document 14 is, as in the cases described above, provided with the photograph of a woman. This image information is again visible in daylight, as in 5a shown. Irradiated this document 14 with infrared light, one finds, as in 5b shown, no grayscale image. It is therefore a forged document 14 in which only one color image 10 was printed. The tamper-proof grayscale image is missing. This is determined by an evaluation of the image information.

This in 6 illustrated fourth example identification document 15 is, as in the cases described above, provided with the photograph of a woman. This image information is again visible in daylight, as in 6a shown. The document 15 differs from the documents shown above in that color formation and grayscale image do not contain identical image information. Instead, it is provided that a numeric code is inscribed below the color image, in this case the date of birth of the document holder. A fake would therefore be recognized immediately if the number code is missing. Now irradiate this document 15 with infrared light, one finds, as in 6b shown, a grayscale image 16 showing the number code. Nevertheless, as in 4 , Color image and grayscale image, it can be assumed at first glance that there is no forgery. To confirm this statement, a subsequent evaluation of the image information, in particular an evaluation of the numerical code and verification of the date of birth, is required.

Conventional devices for checking the authenticity of identification documents usually already comprise the assemblies necessary for carrying out the test method according to the invention, in particular a lighting unit for irradiating the identification document 1 with a first test radiation (eg daylight) for reading the image information of the color image 5 and / or for irradiating the identification document 1 with a second test radiation (eg infrared light) for reading the image information of the gray scale image 6 and an evaluation unit for evaluating, in particular for comparing the obtained image information. For carrying out the method according to the invention, therefore, only an adaptation of the evaluation algorithms is usually required.

Deviations from the exemplified embodiment are possible. For example, the color image 5 also be applied by means of another printing process, if this allows the use of infrared-transmissive ink. In another variant, the grayscale image 6 instead of a birthday another, from the color picture 5 contain various image information, such as a serial number, a crest or other national emblem or the like.

All in the description, the following claims and the drawings illustrated features may be essential to the invention both individually and in any combination.

LIST OF REFERENCE NUMBERS

1

ID card

2

carrier

3

foil

4

film surface

5

color

6

Grayscale image

7

Upper layer

8th

Lower class

9

first document

10

color

11

Grayscale image

12

second document

13

Grayscale image

14

third document

15

fourth document

16

Grayscale image

17

protective layer

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0537484 A1 [0004]

Claims (11)

Identification document ( 1 ) or the like, with two overlapping images ( 5 . 6 ), the images ( 5 . 6 ) are applied in separate working steps, - wherein at least one of the images is present in an externally inaccessible form, - wherein one of the images is a grayscale image ( 6 ) and - wherein one of the images is a color image ( 5 ), which includes both color information and light / dark information. Identification document ( 1 ) or the like according to claim 1, wherein at least portions of the image information of one picture are included in the other picture. Identification document ( 1 ) or the like according to claim 1 or 2, wherein the gray scale image ( 6 ) all image information of the color image ( 5 ) except the color information. Identification document ( 1 ) or the like according to one of claims 1 to 3, wherein the images ( 5 . 6 ) overlap congruently. Identification document ( 1 ) or the like according to claim 1, wherein in none of the pictures ( 5 . 6 ) Image information of the other image are included. Identification document ( 1 ) or the like according to one of claims 1 to 5, wherein the gray scale image ( 6 ) is present in a form not accessible from the outside. Identification document ( 1 ) or the like according to any one of claims 1 to 6, wherein the color image ( 5 ) is permeable to a test radiation with which the grayscale image ( 6 ) is irradiated for test purposes, such that the color image ( 5 ) reading the image information of the grayscale image ( 6 ) not disabled. Method for producing an identification document ( 1 ) or the like, with two overlapping images ( 5 . 6 ), where one of the images is a grayscale image ( 6 ), where one of the images is a color image ( 5 ) comprising both color information and light / dark information, and - the color image ( 5 ) on an image carrier ( 3 ; 7 ) and the grayscale image ( 6 ) by means of a controlled laser beam into an image carrier ( 3 ; 8th ) is introduced. Method according to claim 8, wherein the image carrier ( 3 ) for the color image ( 5 ) at the same time the image carrier ( 3 ) for the grayscale image ( 6 ). Method according to claim 8, wherein the image carriers comprise different, preferably directly adjacent layers ( 7 . 8th ) in the layer structure of the identification document ( 1 ) or the like. Method for checking the authenticity of an identification document ( 1 ) or the like according to any one of claims 1 to 8, comprising the steps of: - irradiating the identification document ( 1 ) or the like having a first inspection radiation for reading the image information of the color image ( 5 ), - irradiation of the identification document ( 1 ) or the like with a second test radiation for reading the image information of the gray scale image ( 6 ), - reading the image information of the color image ( 5 ) and the grayscale image ( 6 ) and - evaluating, in particular comparing the obtained image information.

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