EP4417436A1 - Identification document, decryption application and method for producing an identification document - Google Patents

Abstract

The invention relates to an identification document (1) with an image information layer (10), a lens arrangement (20) and a print layer (30). The print layer (30) is printed on the lens arrangement (20) and contains color information (32) in order to thus form a colored identification image (34) on the identification document (1). The color information (32) has a first color information portion (32a) which comprises a color extract of the colored identification image (34), and a second color information portion (32b) which is integrated into the colored identification image (34) in the form of encrypted information. The image information layer (10) has image information (12) with black-and-white information which correlates with the second color information portion (32b) and can be reconstructed through the lens arrangement (20). The invention further relates to a decryption application and a method for producing an identification document (1).

Description

The present invention relates to identification documents with hidden authenticity information. In particular, the invention relates to an identification document, a decryption application and a method for producing an identification document.

Background of the invention

Identification documents such as ID cards, credit cards or bank cards should offer the greatest possible security against forgery or falsification due to their legitimation function and yet be relatively easy and inexpensive to produce. Hiding encryption information in the identification document, for example in the form of security features, is particularly important because forging an identification document usually requires knowledge of the existence and functioning of such security features. Steganographic hiding of information is a well-known example.

EP 1 484 710 A2 describes a photographic identification document with a photograph and a printed area. A first digital watermark is steganographically encoded in the photograph, whereby the digital watermark transmits initial information that can later be decoded and used to authenticate the document. Additionally, a second digital watermark is steganographically encoded in the printed area of the document, the second digital watermark conveying second information whose contents have an expected match with contents of the first information. The first and second information can be decoded and checked for the expected match to assist in determining whether the photograph or the printed area has been fraudulently altered.

EP 4 064 095 A1 describes an encoding system for a security document with a printer-hardened, steganographically encoded image and a decoding and integrity validation system for a security document with a printer-hardened, steganographically encoded image.

Description

It is an object of the present invention to improve the forgery security of identification documents.

This object is achieved by the subject matter of the independent claims. Exemplary embodiments emerge from the dependent claims and the following description.

According to one aspect, an identification document is specified. The identification document comprises an image information layer for recording image information, a lens arrangement and a print layer for recording color information. The print layer is printed on the lens arrangement in order to form a colored identification image on the identification document using the color information. The color information has a first color information portion recorded in the print layer, which comprises a color extract of the colored identification image. This first color information portion can have a represent the unencrypted color portion of the identification image. The color information also has a second color information portion recorded in the print layer, which is integrated into the colored identification image in the form of encrypted information. This second color information portion can therefore represent an encrypted color portion of the identification image. The image information includes black-and-white information recorded in the image information layer, which correlates with the second color information portion recorded in the print layer and can be reconstructed through the lens arrangement.

The identification document according to the invention makes it possible to provide a security or authenticity feature that is not perceptible to the eye of a viewer in an identification image on the identification document, such as a portrait photo. This security or authenticity feature provided in the identification image can therefore be viewed as hidden or concealed information. It can be provided that the security or authenticity feature can only be detected from the identification image with the aid of a technical detection device.

In addition to capturing the hidden information from the identification image, a further hurdle for potential document forgery can be created by the fact that, under certain conditions, a security or authenticity feature can also be captured from the image information layer of the identification document, which corresponds to the hidden information from the identification image of the print layer. The authenticity or genuineness of the identification document can then be determined by comparing the security or authenticity feature captured from the image information layer with the encrypted information captured from the identification image. A software application or app for execution on a mobile device, such as a mobile phone, can be used for this purpose.

The identification document can be an ID card, a credit card, a bank card or the like. The identification document can have a carrier, in particular a card-shaped carrier, on which the identification image is arranged so that it is visible from the outside. The identification document can be formed, at least in the area of the identification image, by a stacked arrangement of the image information layer, the lens arrangement and the print layer, whereby this stacked arrangement can be provided on the carrier of the identification document. An exemplary structure will be explained in more detail in the description of the figures.

The identification image can be located in the print layer or be formed by it. In particular, the print layer has color information which on the one hand contains the pure color extract of the identification image, for example a photo or a portrait photo of a person, and on the other hand also contains hidden information which can be incorporated into the identification image in the form of a color component. For example, the color extract of the identification image can be a color photo of a person or a color portrait photo, as previously recorded by means of imaging by a camera. In addition to the color extract, the color component of the hidden information can also be included in the identification image, whereby a viewer with the naked eye is not able to perceive this additional color component of the hidden information. Rather, the viewer with the naked eye only sees the color photo of the person or the color portrait photo.

To achieve this, the color information contained in the print layer has the first color information portion that comprises or defines the color separation of the color identification image. This may mean that the first color information portion only contains the color information portion that represents the color photo of the person or the color portrait image as captured by imaging with the camera.

In addition, the color information contained in the print layer may include the second color information portion, which provides the additional color portion for the hidden Information, whereby the second color information component is incorporated into the colored identification image as encrypted information in addition to the color extract. The difference between the identification image without additional color component of the encrypted information and the identification image with additional color component of the encrypted information is not perceptible to a viewer of the identification image, i.e. not visible.

In addition, the identification document also contains the image information, in particular black-and-white information recorded in the image information layer, which correlates with the second color information component recorded in the print layer. For example, it can be provided that the black-and-white information represents a black-and-white component that is assigned to the above-mentioned additional color component in the identification image of the print layer. The black-and-white information can therefore correspond to a black-and-white print of the color component for the hidden information from the identification image. Since the color component for the hidden information can contain the encrypted information, the black-and-white component can also be considered as complementary, encrypted information that is assigned to the hidden or encrypted color component.

It can be provided that part of the encrypted information, namely the additional color portion contained in the printing layer, is printed, while the other part of the encrypted information, namely the black and white portion contained in the image information layer, is lasered.

It can also be provided that the color component for the hidden information or the second color information component in the form of the encrypted information in the identification image can be captured by a camera of a mobile device, namely from all capture directions or viewing directions in relation to the identification image. It can also be provided that the black-and-white component for the hidden information or the black-and-white information in the image information layer can also be captured by the camera of the mobile device, but only starting from a predetermined detection direction, which preferably differs from a perpendicular detection direction in relation to the identification image. The black-and-white information from the image information layer can be reconstructed during detection along the predetermined detection direction through the lens arrangement, so that the detected black-and-white information can then be compared with the detected second color information component.

According to one embodiment, the color separation of the colored identification image represents a photographic image.

For example, the color separation is a color photograph of a person or a color portrait image of a person. In one example, the color separation of the identification image is a biometric photograph.

According to one embodiment, the second color information portion comprises a color portion printed in the colored identification image, which is superimposed on the color separation of the colored identification image.

This can mean that when the identification document is produced, the identification image is printed onto the lens arrangement, whereby both the color extract of the identification image, in particular the photo or portrait image, and the additional color portion of the identification image forming the encrypted information are preferably printed onto the lens arrangement simultaneously or in one step. All of the color information is thus located on the same level on the document surface. This applies to the encrypted and the unencrypted color portion of the identification image. In one example, the additional color portion printed in the colored identification image comprises the encrypted information or this additional color portion represents the encrypted information.

According to one embodiment, the black-and-white information is formed by a black-and-white portion of the printed color portion of the second color information portion.

This can mean that a black and white image of the color portion of the encrypted information contained in the identification image is stored in the image information layer. The image information layer can be a laser-modifiable layer and/or the black and white information can be introduced into the image information layer using a laser. In other words, the black and white information belonging to the photo can be introduced into the image information layer under the lens arrangement using a laser. For example, a black and white portion of the hidden or encrypted information can be introduced into the image information layer at a predetermined angle. This predetermined angle in relation to a vertical direction on the identification document can be a maximum of 30°.

According to one embodiment, the second color information portion comprises text information.

This can mean that the hidden information or the encrypted information, which can be represented by the second color information component in the print layer, results from plain text information, for example a document number or a sequence of alphanumeric characters, in particular after encryption. The hidden information or the encrypted information is designed in such a way that it is not immediately visible to a viewer in the photo. The hidden information or the encrypted information can, for example, be a pattern that is superimposed on a photo or portrait photo with a low dot density. The encrypted information can be encrypted with up to eight bits, for example the first eight digits of a document number of the identification document.

According to one embodiment, the lens arrangement is arranged in relation to the image information layer such that the black-and-white information can only be reconstructed through the lens arrangement in a predetermined detection direction, wherein the predetermined detection direction differs from a perpendicular detection direction with respect to the identification document.

The lens arrangement can in particular cause a specific refraction behavior so that the image information contained in the image information layer, i.e. the black and white information, can only be captured or reconstructed at an oblique angle in relation to the identification document surface and/or the identification image surface. In particular, it can be provided that the image information cannot be captured or reconstructed in the case of a perpendicular capture direction in relation to the identification document surface and/or the identification image surface.

The term "detection direction" is described here. However, it should be understood that the term "viewing direction" can be used analogously.

According to one embodiment, the predetermined detection direction and the vertical detection direction enclose an angle of at most 40°. In one example, the predetermined detection direction and the vertical detection direction enclose an angle of at most 30°.

In other words, the predetermined detection direction is tilted relative to the vertical detection direction, wherein the vertical detection direction defines, for example, a direction that runs perpendicular or normal to the identification document surface and/or identification image surface.

According to one embodiment, the second color information portion of the print layer can be reconstructed both in the vertical detection direction on the identification document and in the predetermined detection direction.

In other words, the hidden or encrypted information of the print layer can be captured from any angle to the identification document surface and/or identification image surface. However, as previously indicated, it can be provided that the hidden or encrypted information cannot be perceived visually and thus by the eye of a viewer. However, it can be provided that the hidden or encrypted information can be captured with a suitable capture device, for example a camera of a mobile device.

According to one embodiment, the printing layer is a partially transparent printing layer formed by a rasterized printing layer with opaque raster elements and transparent gaps.

The color information can be contained in the opaque raster elements. However, it is also possible for the partially transparent print layer to be formed by a full-surface, translucent print that contains the color information. The partially transparent print layer is applied directly to the lens arrangement, for example.

According to one embodiment, the lens arrangement is formed by a relief structure with elevations and depressions located between the elevations. The previously described opaque raster elements of the partially transparent printing layer can be arranged at least partially in the depressions of the relief structure.

In the event that the partially transparent printing layer is formed by a rasterized printing layer, the raster elements of the partially transparent printing layer can be arranged at least partially or predominantly in the recesses of the relief structure. The combination of the partially transparent printing layer with the lens arrangement can therefore form a lenticular grid, with the color information of a photo and the incorporated, additional color portion of the hidden information being printed onto the lenticular grid in a common printing pass. By arranging the raster elements partially or predominantly in the recesses of the lens arrangement The raster elements of the partially transparent printing layer can be protected from environmental influences and mechanical damage.

According to one embodiment, the color information is introduced into the print layer by means of a printing process and/or the image information is introduced into the image information layer by means of a laser process.

The print layer can be applied to the lens arrangement with the color information, including the first color information portion and the second color information portion. It can also be provided that after the lens arrangement and the image information layer have been joined together, the image information, i.e. the black and white information, is introduced into the image information layer by means of a laser beam while the laser beam passes through the lens arrangement.

According to one aspect, a use of a mobile device, in particular a mobile phone, for capturing the image information and at least the second color information portion from the identification document, as described herein, is specified.

In particular, the use of the mobile device comprises the detection of the black and white information contained in the image information layer in the predetermined detection direction and the detection of the color component contained in the print layer, which represents the encrypted information, in any detection direction.

According to one aspect, a decryption application is provided. The decryption application serves to decrypt encrypted information contained in an identification document, wherein the decryption application comprises instructions that can be executed by a processor of a mobile device. In one step, the instructions comprise an instruction for capturing a colored identification image of a print layer of the identification document. In a further step, the instructions comprise a Instruction for capturing a color information component contained in the print layer, for example the previously described second color information component, which is integrated in the form of encrypted information in the color identification image. In a further step, the instructions comprise an instruction for capturing black-and-white information contained in an image information layer of the identification document, wherein the black-and-white information is captured through a lens arrangement of the identification document and in a predetermined capture direction in relation to the identification document, which differs from a perpendicular capture direction in relation to the identification document. In a further step, the instructions comprise an instruction for determining whether the captured color information component correlates with the captured black-and-white information.

According to one embodiment, the instructions further comprise an instruction for processing the encrypted information in response to determining that the captured color information portion correlates with the captured black and white information. For example, a decryption of the encrypted information may take place.

A neural network (for example a so-called deep learning neural network) can be used for decryption. The neural network can be designed to learn an encoding and decoding algorithm so that different types of image disturbances caused by image compression, digital transmission, printers, ambient lighting and digital cameras can be taken into account in a robust manner.

According to one aspect, a method for producing an identification document is provided. In one step, a lens arrangement is provided. In a further step, a printing layer is printed onto the lens arrangement, wherein the printing layer comprises color information for generating a colored identification image on the identification document, wherein the color information has a first color information portion which comprises a color separation of the colored identification image, and wherein the color information has a second color information portion, in which the colored identification image is integrated in the form of encrypted information. The first color information component and the second color information component are preferably printed simultaneously onto the lens arrangement. In a further step, an image information layer is provided. In a further step, image information is introduced into the image information layer by means of laser exposure in order to generate black-and-white information in the image information layer which correlates with the second color information component contained in the print layer and can be reconstructed through the lens arrangement.

Short description of the characters

Fig.1

shows an identification document.

Fig.2

shows a cross-section of the identification document along the line II-II of Fig.1 during viewing by a human observer.

Fig.3

shows a cross-section of the identification document along the line II-II of Fig.1 during a capture process by a mobile device.

Fig.4

shows a composition of color information for an identification image of an identification document.

Fig.5

shows a flow chart for a decryption application for decrypting encrypted information contained in an identification document.

Fig.6

shows a flow chart for a method for producing an identification document.

Detailed description of exemplary embodiments

The representations in the figures are schematic and not to scale. If the same reference symbols are used in different figures in the following description of the figures, these refer to identical or similar elements. Identical or similar elements can also be referred to by different reference symbols.

Fig.1 shows a top view of an identification document 1, for example an identification card such as an identity card in credit card format. The identification document 1 has an identification image 34 in a personalization area 3. The identification document 1 also has a bibliography area 4. The identification document 1 can comprise a carrier 2, for example made of a plastic material, wherein the carrier 2 forms the basis for the identification document 1 and the personalization area 3 and the bibliography area 4 are arranged thereon.

The personalization area 3 is designed to record the identification image 34, wherein the identification image 34 has, for example, biometric image information that serves to identify the holder of the identification document 1. The bibliography area 4 is designed to record further information, for example about the cardholder and the identification document 1 itself.

In the personalization area 3, when viewed vertically or at an angle by a viewer of the identification document 1, a colored, biometric passport photo of the holder is visible, which is generally referred to below as identification photo 34. The viewer cannot obtain any further information by simply looking at the identification photo 34. In particular, the viewer cannot see that an additional color information component has been added to the identification photo 34 in addition to a color extract of the identification photo 34. This additional color information component, which is also referred to herein as the second color information component, is, for example, superimposed on the color extract of the identification photo 34 and changes the appearance of the pure color extract of the identification photo 34 in such a way that such a small extent that the viewer cannot visually recognize this additional color information component in the identification image 34.

The Figures 2 and 3 serve to explain in more detail the structure and functioning of an identification document 1, for example the identification document 1 of the Fig.1 . The Figures 2 and 3 show a cross-section of the identification document 1 in the personalization area 3, in particular in the identification image 34, along the line II-II of Fig.1 .

Fig.2 shows first a cross-section of the identification document 1 along the line II-II of Fig.1 during observation by a human observer 40, 42.

As can be seen, the identification document 1 comprises an image information layer 10 for receiving image information 12, a lens arrangement 20 and a printing layer 30 for receiving color information 32. The printing layer 30 is printed on the lens arrangement 20 in order to form the colored identification image 34 on the identification document 1 using the color information 32.

In the present example, the printing layer 30 is designed as a partially transparent printing layer, which is formed by a rasterized printing layer with opaque raster elements 36 and transparent gaps 38. In the present example, the lens arrangement 20 is formed by a relief structure with elevations 22 and depressions 24 located between the elevations 22, wherein the opaque raster elements 36 of the partially transparent printing layer are arranged in the depressions 24 of the relief structure. The elevations 22 are semicircular in cross-section. When considering the lens arrangement 20 as a whole, the elevations 22 can be parallel cylindrical lenses of the lens arrangement 20. The cylindrical lenses can be designed in the form of narrow, cylindrical microlenses with a width below the resolution limit of the human eye, for example a width of only 50 µm. An optical spacing layer can also be provided between the lens arrangement 20 and the image information layer 10. In particular, provision can be made be such that the distance of the cylindrical lenses to the image information layer 10 essentially corresponds to the focal length of the cylindrical lenses, as can be seen from the dashed lines in the Fig.3 can be removed.

The print layer 30 contains color information 32, which in turn has a first color information portion that includes or defines the above-mentioned color separation of the colored identification image 34. The first color information portion can thus represent a non-hidden or encrypted color portion of the identification image 34, which is visible both to a viewer 40 in a vertical viewing direction 41 and to a viewer 42 in an oblique viewing direction 43. The color separation of the colored identification image 34 is in particular a photographic image or a photo.

The color information 32 contained in the print layer 30 also has the second or additional color information component already mentioned above, which is integrated in the form of encrypted information in the color identification image 34. The second color information component in the print layer 30 can thus represent a hidden or encrypted color component that has been added to the first color information component, i.e. the non-encrypted color component of the identification image 34, and is virtually superimposed on it. The encrypted color component can, for example, be a printed additional color component that is printed as a pattern with a low dot density to the color component of the color separation. The color component of the color separation and the additional, encrypted color component are preferably printed simultaneously in one printing step onto the lens arrangement 20. This additional, hidden or encrypted color component is not visible to the viewer 40 when viewed in a vertical direction 41 or when viewed in an oblique direction 43, i.e. it cannot be distinguished from the first color information component.

In other words, a viewer 40, 42 perceives only the first color information component from all viewing directions 41, 42 and thus the pure color extract of the identification image 34 without recognizing the second color information component, which is superimposed on the color separation as an additional, encrypted color component.

The image information layer 10 contains the image information 12. The image information 12 comprises black and white information which correlates with the second color information component recorded in the print layer 30, i.e. the additional, encrypted color component. The image information 12 or the black and white information is not visible to the viewer 40 either in the vertical viewing direction 41 or in the oblique viewing direction 43. The black and white information can be provided below the lens arrangement 20 in such a way that the black and white information can only be reconstructed through the lens arrangement 20 using a suitable image analysis or imaging method, as is now shown using the Fig.3 is explained.

Fig.3 shows a cross-section of the identification document 1 along the line II-II of Fig.1 during capture by a mobile device 50. The mobile device 50 may be a portable or handheld device, such as a mobile phone or a tablet computer.

A detection by the mobile device 50 along an oblique detection direction 60 and along a vertical detection direction 62 is shown. The structure of the identification document 1, including its components and functions, corresponds to that of the Fig. 2 In particular, the identification document 1 comprises the image information layer 10, the lens arrangement 20 and the print layer 30, including their characteristics and functions, as already described with reference to Fig. 2 described.

The print layer 30 contains the color information 32, which in turn has the first color information portion, which comprises the color separation of the colored identification image 34. As described, the first color information portion represents the non-hidden or encrypted color portion of the identification image 34, which can be optically detected or reconstructed by the mobile device 50, in particular by a camera 54 of the mobile device 50, in a vertical detection direction 62 as well as in an oblique detection direction 60.

As described, the color information 32 contained in the print layer 30 also has the second or additional color information component, which is integrated in the form of encrypted information in the color identification image 34. The second color information component in the print layer 30 represents the hidden or encrypted color component that was added to the first color information component, i.e. the non-encrypted color component of the identification image 34, and is virtually superimposed on it. This additional, hidden or encrypted color component of the identification image 34 can be optically detected or reconstructed by the mobile device 50, in particular by the camera 54 of the mobile device 50, both in the vertical detection direction 62 and in the oblique detection direction 60. This means that the additional, hidden or encrypted color portion of the identification image 34 can be optically detected or reconstructed by the mobile device 50 at any detection angle with respect to the identification document surface or the identification image surface.

As described, the image information 12 is contained in the image information layer 10. The image information 12 comprises the black-and-white information that correlates with the second color information component contained in the print layer 30, i.e. the additional, encrypted color component. The black-and-white information can have been introduced into the image information layer 10 by laser. The image information 12 or the black-and-white information cannot be optically captured or reconstructed by the mobile device 50 in a vertical viewing direction 62. A specific, predetermined detection angle is therefore required, according to which the camera 54 of the mobile device 50 is to be aligned with the identification document 1 in order to optically capture or reconstruct the black-and-white information from the image information layer 10. The black-and-white information is therefore below the lens arrangement in such a way 20, it is provided that the black-and-white information can be optically detected or reconstructed through the lens arrangement 20 only when detected along the predetermined oblique detection direction 60 and/or using a suitable image analysis or imaging method.

In other words, the encrypted information of the additional color component contained in the print layer 30 can be recovered at the same time as the black-and-white information is recovered from the image information layer 10, namely at the predetermined oblique detection direction 60, which differs from the vertical detection direction 62, but preferably encloses an angle of a maximum of 30° with the vertical detection direction 62. This means that 100% of the encrypted information can be read out at the oblique or tilted angle. This works because only the black-and-white information or the lasered black-and-white component becomes invisible when detected at 90° to the card surface. The printed, additional color component in the print layer 30, on the other hand, is visible at any detection angle. As soon as the identification document 1 is tilted, both parts, i.e. the additional or encrypted color component and the black-and-white component, are visible at the same time.

A corresponding image analysis or imaging can be carried out by means of a processor 52 of the mobile device 50. Likewise, a decryption application as described with respect to the Fig.5 will be explained in more detail, are executed on the processor 52 of the mobile device 50. As part of a decryption, the processor 52 can execute instructions for capturing the second color information portion, i.e. the additional, encrypted color portion from the print layer 30, in order to thereby capture the hidden or encrypted color portion from the identification image 34. Furthermore, the processor 52 can execute instructions for capturing the black and white information from the image information layer 10 at the predetermined capture angle or along the predetermined oblique capture direction 60, in order to thereby capture the black and white information correlating with the hidden or encrypted color portion. Furthermore, the processor 52 Execute instructions for processing or comparing the hidden or encrypted color portion with the black and white information in order to check the authenticity of the identification document 1 or the identification image 34. In particular, such a check can reveal a possible forgery or manipulation of the identification image 34.

Fig.4 shows a composition of color information for an identification image of an identification document. The Fig.4 shows in particular the composition of the colour information 32 for the identification image 34 of the identification document 1 of the Figures 1 to 3 .

The color information 32 contained in the print layer 30 comprises, on the one hand, the pure color extract of the identification image 34, for example a photo or a portrait photo of a person, as it was previously recorded by means of imaging by a camera. The color extract is defined or represented by the first color information portion 32a. Such a pure color extract of the identification image 34 is shown in the upper left illustration of the Fig.4 to see.

On the other hand, the color information 32 contained in the print layer 30 also includes the hidden information that is incorporated into the identification image in the form of the additional color component. This additional color component in the identification image 34 is defined or represented by the second color information component 32b. Such an additional color component of the identification image 34 is shown in the upper right illustration of the Fig.4 For explanatory purposes only, the additional color component of the identification image 34 of the upper right illustration of the Fig.4 as a facial contour. However, the additional color component can take on different patterns or shapes.

The lower illustration in Fig.4 now shows a superposition of the pure color extract of the identification image 34 with the additional color component, that is, a superposition of the first color information component 32a with the second color information component 32b. the additional color component in the identification image 34, at least for the eye of a human observer, cannot be distinguished from the pure color extract of the identification image 34. Thus, an observer with the naked eye is not able to perceive this additional color component of the hidden information. Rather, the observer with the naked eye only sees the colored photo of the person or the colored portrait image. Ultimately, this means that for an observer, the photo in the upper left representation in Fig.4 not from the lower illustration in Fig.4 is distinguishable.

Fig.5 shows a flow chart for a decryption application for decrypting encrypted information contained in an identification document. The decryption application can be used to decrypt the information contained in the identification document 1 of Fig.1 The decryption application comprises instructions that are executed by the processor 52 of the mobile device 50 of Fig.3 are executable. In a step S10, the instructions include an instruction for capturing the colored identification image 34 in the print layer 30 of the identification document 1. In a further step S11, the instructions include an instruction for capturing the second color information portion 32b contained in the print layer 30 (cf. Fig.4 ), which is integrated in the form of the encrypted information into the color identification image 34. In a further step S12, the instructions comprise an instruction for capturing the black-and-white information contained in an image information layer 10 of the identification document 1, wherein the capturing of the black-and-white information takes place through the lens arrangement 20 of the identification document 1 and along the predetermined capturing direction 60 with respect to the identification document 1, which differs from the perpendicular capturing direction 62 with respect to the identification document 1. In a further step S13, the instructions comprise an instruction for determining whether the captured second color information portion 32b correlates with the captured black-and-white information. In a further optional step S14, the instructions comprise an instruction for processing the encrypted information in response to determining that the captured second color information portion 32b correlates with the captured black-and-white information correlated. Processing may include decrypting the encrypted information.

In order to check a photo on the identification document 1, the mobile device 50 can be used to read a photo of the identification document 1 itself from above. The black and white portion of the hidden information applied to the image information layer 10 can also be read from an angle. At the same time as the black and white portion, the printed color portion of the hidden information is read from the print layer 30, which is equally visible from all angles. The decryption application can be applied to the hidden information read out in total in order to recover any plain text information contained therein.

Fig.6 shows a flow chart for a method for producing an identification document, for example the identification document 1 of the Figures 1 to 3 . In a step S20 of the method, a lens arrangement 20 is provided. In a further step S21, a printing layer 30 is printed onto the lens arrangement 20, wherein the printing layer 30 comprises color information 32 for generating a colored identification image 34 on the identification document 1, wherein the color information 32 comprises a first color information portion 32a (cf. Fig.4 ) which comprises a color extract of the colored identification image 34, and wherein the color information 32 comprises a second color information portion 32b (cf. Fig.4 ) which is integrated in the form of encrypted information into the colored identification image 34. In a step S22, an image information layer 10 is provided. In a step S23, image information 12 is introduced into the image information layer 10 by means of a laser exposure in order to thus generate black-and-white information in the image information layer 10 which correlates with the second color information portion 32b contained in the print layer 30 and can be reconstructed through the lens arrangement 20.

Claims (15)

Identification document (1), comprising: an image information layer (10) for receiving image information (12); a lens arrangement (20); a printing layer (30) for receiving color information (32); wherein the printing layer (30) is printed on the lens arrangement (20) so as to form a colored identification image (34) on the identification document (1) using the color information (32); wherein the color information (32) has a first color information portion (32a) recorded in the printing layer (30), which comprises a color extract of the colored identification image (34); wherein the color information (32) has a second color information portion (32b) recorded in the printing layer (30), which is integrated into the colored identification image (34) in the form of encrypted information; wherein the image information (12) comprises black-and-white information recorded in the image information layer (10), which correlates with the second color information component (32b) recorded in the print layer (30) and can be reconstructed through the lens arrangement (20). Identification document (1) according to claim 1,
wherein the color extract of the colored identification image (34) represents a photographic image. Identification document (1) according to one of the preceding claims,
wherein the second color information portion (32b) comprises a color portion printed in the color identification image (34) which is superimposed on the color separation of the color identification image (34). Identification document (1) according to claim 3,
wherein the black and white information is formed by a black and white portion of the printed color portion. Identification document (1) according to one of the preceding claims,
wherein the second color information portion (32b) comprises text information. Identification document (1) according to one of the preceding claims, wherein the lens arrangement (20) is arranged in relation to the image information layer (10) such that the black-and-white information can be reconstructed through the lens arrangement (20) only in a predetermined detection direction (60); wherein the predetermined detection direction differs from a perpendicular detection direction (62) on the identification document (1). Identification document (1) according to claim 6,
wherein the predetermined detection direction (60) and the vertical detection direction (62) enclose an angle of at most 40°. Identification document (1) according to one of claims 6 or 7,
wherein the second color information portion (32b) of the print layer (30) can be reconstructed both in the vertical detection direction (62) on the identification document (10) and in the predetermined detection direction (60). Identification document (1) according to one of the preceding claims,
wherein the printing layer (30) is a partially transparent printing layer which is formed by a rasterized printing layer with opaque raster elements (36) and transparent gaps (38). Identification document (1) according to claim 9,
wherein the lens arrangement (20) is formed by a relief structure with elevations (22) and depressions (24) located between the elevations (22), wherein the opaque raster elements (36) of the partially transparent printing layer are at least partially arranged in the depressions (24) of the relief structure. Identification document (1) according to one of the preceding claims,
wherein the color information (32) is introduced into the print layer (30) by means of a printing process and/or the image information (12) is introduced into the image information layer (10) by means of a laser process. Use of a mobile device (50) for capturing the image information (12) and the second color information portion (32b) from the identification document (1) according to one of the preceding claims. Decryption application for decrypting encrypted information contained in an identification document (1), the decryption application comprising instructions executable by a processor (52) of a mobile device (50), the instructions comprising: Capturing a colored identification image (34) of a print layer (30) of the identification document (1, S10); Detecting a color information portion (32b) contained in the print layer (30) which is integrated into the colored identification image (34) in the form of encrypted information (S11); Capturing black-and-white information contained in an image information layer (10) of the identification document (1), wherein the capturing of the black-and-white information takes place through a lens arrangement (20) of the identification document (1) and at a predetermined capturing direction (60) with respect to the identification document (1) which differs from a perpendicular capturing direction (62) with respect to the identification document (1) (S12); Determining whether the detected color information component (32b) correlates with the detected black and white information (S13). The decryption application of claim 13, wherein the instructions further comprise:
Processing the encrypted information in response to determining that the detected color information portion (32b) correlates with the detected black and white information (S14). Method for producing an identification document (1), comprising: Providing a lens arrangement (20, S20); Printing a printing layer (30) onto the lens arrangement (20), wherein the printing layer (30) comprises color information (32) for generating a colored identification image (34) on the identification document (1), wherein the color information (32) has a first color information portion (32a) which comprises a color extract of the colored identification image (34), and wherein the color information (32) has a second color information portion (32b) which is integrated into the colored identification image (34) in the form of encrypted information (S21); Providing an image information layer (10, S22); Introducing image information (12) into the image information layer (10) by means of laser exposure in order to thereby generate black-and-white information in the image information layer (10) which correlates with the second color information component (32b) contained in the print layer (30) and can be reconstructed through the lens arrangement (20) (S23).

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