Method for manufacturing a display body, a display body, and a method for verifying the authenticity of a display body

Abstract

This display body is provided with a base material having a first region, a second region, and a third region. In the display body, a code of identification information and an image are formed in the first region, a hidden code including information obtained by coding at least part of the identification information is formed in the second region, and an encrypted ciphertext is recorded in the third region. The ciphertext is generated from the code of the identification information and / or the hidden code.

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE The present invention relates to a method for manufacturing an indicia, ... and a method for verifying the authenticity of an indicia. This application claims priority to Japanese Patent Application No. 2019-218137, filed in Japan on December 2, 2019, the contents of which are incorporated herein by reference. Further, a method for reading the indicia, an observation device, and a method for verifying authenticity are also mentioned. [Background technology]

[0002] Various ID (IDentification) cards such as passports and driver's licenses are known as display media that contain personal information. Many ID cards display facial images and text information to allow visual identification of personal information. If personal information is simply printed on a display media, it can easily be tampered with or forged.

[0003] As a method for preventing counterfeiting of a display, Patent Document 1 describes providing a hologram transfer foil to the display to improve the falsification prevention properties of the display. Patent Document 2 describes the use of a fluorescent material to add personal information that is transparent and invisible under visible light observation but visible under ultraviolet light observation.

[0004] The anti-counterfeiting technology described in Patent Document 1 is already widely known, and in addition, if a general hologram that emits rainbow-colored diffracted light is used, it is not difficult to counterfeit it, so there is room for improvement. Patent Document 3 describes a further method for preventing counterfeiting, in which authenticity is verified using reconstructed information displayed on a hologram by irradiating the hologram with light of a specific wavelength. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 6-67592 [Patent Document 2] Japanese Patent No. 3198324 [Patent Document 3] Japanese Patent No. 4677683 Summary of the Invention [Problem to be solved by the invention]

[0006] In the technology described in Patent Document 3, the reproduced information is designed in advance and is immutable. Therefore, if a counterfeiter learns the reproduced information, there is a possibility that he or she could create a hologram that imitates the reproduced information, and there is still room for improvement.

[0007] In consideration of the above circumstances, an object of the present invention is to provide a display body that has a simple configuration and can suitably prevent tampering and counterfeiting. [Means for solving the problem]

[0008] According to a first aspect of the present invention, a method for manufacturing a display includes generating a concealment code from identification information, encrypting the concealment code to generate a ciphertext, forming at least one of a code and an image of the identification information on a substrate by at least one of thermal transfer and laser engraving, and engraving the concealment code on a substrate by thermal transfer or security printing. The above The code is formed on a substrate and the code is printed on the substrate by at least one of thermal transfer and laser engraving. The above Recording on substrate The concealment code is formed by applying external energy to a hologram transfer foil having a hologram structure to thermally transfer a hologram film to the substrate, and a plurality of the hologram structures are transferred. The position of at least one reconstructed image of the hologram structure in the thickness direction of the substrate is different from the position of the at least one reconstructed image on the surface of the substrate, and is different from the positions of other reconstructed images in the thickness direction of the substrate. .

[0009] According to a second aspect of the present invention, a display comprises a substrate having a first region, a second region, and a third region. Identification information is formed in the first region, and a concealment code including information obtained by encoding at least a part of the identification information is formed in the second region. An encrypted ciphertext is recorded in the third region. The ciphertext is generated from at least one of the code of the identification information and the concealment code. At least one of the plurality of information elements constituting the concealment code or the cipher text has a hologram structure, the concealment code or the cipher text has a plurality of hologram structures, and the reconstructed images of the plurality of hologram structures are located at positions spaced apart from the surface of the base material, and the position of at least one of the reconstructed images of the plurality of hologram structures in the thickness direction of the base material is different from the position of the at least one reconstructed image on the surface of the base material, and is different from the positions of other reconstructed images in the thickness direction of the base material. .

[0010] According to a third aspect of the present invention, there is provided a method for verifying authenticity of a display medium, for verifying whether or not the display medium according to the first aspect is authentic. A method of verifying authenticity includes obtaining the identification information and the concealment code from the display body, and verifying whether the display body is authentic based on the obtained identification information and the concealment code. Effect of the Invention

[0011] The display of the above aspect can effectively prevent tampering and counterfeiting with a simple configuration. Furthermore, the authenticity can be verified by a concealment code that produces a special visual effect under specific observation conditions, and in addition, forensic verification is possible by a cipher text. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a plan view conceptually showing a display according to a first embodiment of the present invention. [Figure 2A] FIG. 2 is a perspective view of the display unit of FIG. [Figure 2B] FIG. 2 is a schematic cross-sectional view of the display of FIG. 1, and shows the position of a reconstructed image. [Figure 3A] 3 shows an example of the positional relationship between a substrate and identification information. [Figure 3B] 3 shows an example of the positional relationship between a substrate and identification information. [Figure 4A] 2 is an enlarged schematic view of a second region of the display of FIG. 1. [Figure 4B] 3A and 3B show schematic diagrams illustrating the position of a holographic reconstruction image in the second region. [Figure 5A] 2 shows an example of the positions of the second area and the third area in the display of FIG. 1. [Figure 5B] 2 shows an example of the positions of the second area and the third area in the display of FIG. 1. [Figure 5C] 2 shows an example of the positions of the second area and the third area in the display of FIG. 1. [Figure 6] 1 is an example of a process flow relating to a method for manufacturing a display. [Figure 7] 1 is an example of a process flow relating to a method for manufacturing a display. [Figure 8A] FIG. 2 is a perspective view of a hologram film. [Figure 8B] FIG. 8B is a cross-sectional view taken along line II in FIG. 8A, and shows a schematic diagram of the position of a reconstructed image. [Figure 9A] FIG. 2 is a schematic diagram showing a process by which information elements are transferred from a holographic film. [Figure 9B] FIG. 2 is a schematic diagram showing a process by which information elements are transferred from a holographic film. [Figure 10] 10 is a flowchart showing a procedure for verifying the authenticity of a display body. [Figure 11A] FIG. 2 is a schematic diagram showing an observation device for a display body. [Figure 11B] FIG. 2 is a schematic diagram showing an observation device for a display body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, one embodiment of the present invention will be described with reference to FIGS. The embodiments of the present invention are a group of embodiments based on a single unique invention. Also, each aspect of the present invention is an aspect of a group of embodiments based on a single invention. Each configuration of the present invention may have each aspect of the present disclosure. Each feature of the present invention can be combined to form each configuration. Therefore, each feature of the present invention, each configuration of the present invention, each aspect of the present disclosure, and each embodiment of the present invention can be combined, and the combination can exhibit a cooperative function and a synergistic effect. 1 is a plan view conceptually showing a display 100 according to the present embodiment. The display 100 has a first region 11, a second region 12, and a third region .

[0014] At least one of a code and an image of the identification information 21 is formed in the first region 11. This code can be visible. Also, it can be identifiable by a reader. The reader may include a line sensor or an image sensor. Also, the reader may include a light source. As shown in FIG. 1, the visible code can be a combination of text, letters, numbers, and symbols. These codes are visually readable. That is, the identification information 21 can be recorded as a visually readable code. Also, the image of the identification information 21 can be a face image or a signature. The identification information 21 can be personal information of the owner of the display body 100. The personal information of the owner is the name, date of birth, country of origin, place of origin, and personal identification number. These personal information can be recorded as a code in the form of a combination of letters, numbers, symbols, and the like. In FIG. 1, the face image of the owner is recorded as identification information in an oval portion in the first region 11. The identification information can be biometric information of the owner. The biometric information can be a face image, a signature image, or a biometric feature. The biometric feature can be recorded as a code in the first area 11. The face image also constitutes a part of the identification information formed in the first area 11. The identification information can be converted into a code according to a certain rule. That is, a code can be generated from the identification information. This code can be digital data. The digital data can be 1 byte or more and 256 bytes or less. When the image is converted into digital data, the data can be 1 Mbyte or more and 1 Gbyte or less. The image may be digital data of 10 kbyte or more and less than 1 Mbyte. The code and image data can be fixed length or variable length. If the data is fixed length, it is easy to process the data. If the data is variable length, the amount of data can be reduced. The identification information is discretized when it is converted into a code of digital data. The code recorded in the first area 11 can be interpreted to obtain the identification information. Although the code is not the same as the identification information, a specific single or specific multiple objects can be identified and selected from a specific group by the code generated from the identification information. If the identification information is a product serial number, the target product can be identified from multiple products. If the identification information is personal information, an individual can be identified from a code generated from the identification information. The cryptogram can be recorded as a code. The code or image can be formed as the shape, size, and arrangement of an area with specific physical properties. The formed code exists as a substance or a space surrounded by a substance. The image can also be recorded as the shape, size, and arrangement of an area with specific physical properties. The recorded image exists as a substance or a space surrounded by a substance.

[0015] The substrate 30 forming the display 100 is, for example, a polycarbonate sheet. Since the polycarbonate resin of the polycarbonate sheet is carbonized by the heat of the laser beam, it is possible to form at least one of a code and an image of the identification information in the first region by the laser beam. That is, the identification information 21 can be formed as at least one of a code and an image in the first region by laser engraving. Furthermore, since the polycarbonate resin of the polycarbonate sheet is carbonized by the heat of the laser beam, it is possible to record a ciphertext in the third region by the laser beam. That is, the ciphertext can be recorded by laser engraving. Since these recorded codes are difficult to erase, it is difficult to rewrite and tamper with a code once recorded.

[0016] At least one of the code and the image of the identification information 21 can be formed by thermal transfer. The identification information 21 may be directly thermally transferred to the substrate 30. Alternatively, a substrate on which the identification information 21 has been thermally transferred in advance may be laminated to another substrate. In this manner, the display body 100 may be formed. The identification information 21 is thermally transferred partially to the substrate by a thermal head using at least one of a thermal transfer ribbon on which a transferable ink layer is formed and a hologram transfer foil on which a thermally transferable hologram is formed, so that at least one of the code and the image of the identification information 21 can be formed in the first region. In particular, by making the thermal transfer ribbon a dye-sublimation type, a high-quality image can be formed. The hologram transfer foil can be formed with a hologram structure that reflects diffracted light corresponding to red, green, and blue. The hologram structures that reflect diffracted light corresponding to red, green, and blue may be formed sequentially in the longitudinal direction of the transfer foil. In this manner, a color image can be formed with one hologram transfer foil. Since it is difficult to form an image of the owner's face with a hologram transfer foil, an image of the owner's face is formed with a hologram transfer foil as an image of identification information, and the image is compared with the owner, thereby making it possible to visually verify whether or not there has been any impersonation. Also, the ciphertext 25 can be recorded in the third area by partially thermally transferring, to a substrate, at least one of a thermal transfer ribbon on which a thermally transferable ink layer is formed and a hologram transfer foil on which a thermally transferable hologram is formed, using a thermal head. In other words, the ciphertext 25 can be recorded in the third area by partially thermally transferring, to a substrate, at least one of a transfer foil on which a thermally transferable ink layer is formed and a transfer foil on which a thermally transferable hologram is formed, using a thermal head. Alternatively, at least one of the code and the image of the identification information 21 may be formed by inkjet printing. Also, the cipher text 25 may be recorded by inkjet printing. Inkjet printing is simple and convenient. Substrate 30 can be laser engravable and / or thermal transferable, and may also be inkjet printable.

[0017] By directly laser engraving the substrate 30 or positioning the printed portion inside the substrate by the above-mentioned overlapping, the identification information 21 is more likely to be destroyed when the display 100 is counterfeited or tampered with, making it easier to verify whether counterfeiting or tampering has occurred. Fig. 3A shows a schematic example in which the identification information 21 is located inside the substrate 30. Fig. 3B shows a schematic example in which the identification information 21 is located on the surface of the substrate 30. The identification information 21 can also be formed inside the substrate 30 by focusing a laser beam inside the substrate 30.

[0018] 1, in display body 100, a part of second region 12 and third region 13 are located within first region 11 and overlap when viewed in a plan view of display body 100. In this way, in addition to the structures of second region 12 and third region 13 described below, the positional relationship between them must also be taken into consideration when counterfeiting or tampering, making counterfeiting and tampering more difficult. The manner in which the regions 11, 12, and 13 overlap, the size of the overlapping area, and the like can be determined according to the ease of viewing for the user. The first area 11, the second area 12, and the third area 13 may not overlap. In this way, the visibility of each area can be improved. In addition, a security patch may be further superimposed on any of the areas. The security patch may be a hologram film of a predetermined shape that is thermally transferred with a thermally transferable hologram transfer foil having a hologram structure formed thereon. The hologram film may be a laminate of a layer having a hologram structure formed thereon and an adhesive layer. The outer shape of the security patch may be a circle, an ellipse, or a rectangle with rounded corners. The shape of the security patch may be determined by the shape of the die head used for thermal transfer. The thermal transfer of the hologram transfer foil with the die head is also called hot stamping.

[0019] A hidden code 22 is formed in the second area 12. A ciphertext 25 is recorded in the third area 13. In this embodiment, the contents of the hidden code 22 and the ciphertext 25 are the same as a part of the identification information 21. In addition, the hidden code 22 recorded by laser engraving or printing and a reconstructed image 24 of the hidden code 22 formed by a holographic film described later may be aligned so as to completely overlap in a planar view. This printing may be security printing described later. In the example of FIG. 1, the ciphertext 25 formed by laser engraving or inkjet printing and reconstructed images 27A, 27B of the ciphertext 25 formed by a holographic film described later are aligned so as to overlap in a planar view. Specifically, the identification information 21 is a code consisting of a string of characters that combines symbols, numbers, and letters as shown in FIG. 1, the concealment code 22 is the string “DOME”, and the cipher text 25 is “AJPN012345”, which is a combination of letters and numbers. The concealed code may be formed only from a hologram film. The ciphertext 25 may be recorded only by laser engraving or inkjet printing. The concealed code may be formed only from a hologram film, and the ciphertext 25 may be formed only by laser engraving or printing. This makes it possible to realize both counterfeit resistance and ease of manufacture. The concealed code 22 may be formed by security printing. The security printing may be a latent image made of fine lines formed in different directions. The recorded code can be visually recognized by reflection observation from a specific direction, transmission observation, or superposition of a line filter. The security printing may also be printing of invisible ink or variable ink. The variable ink may be pearl ink, cholesteric liquid crystal ink, or magnetic ink. The invisible ink may be fluorescent ink. The fluorescent ink can be visualized by irradiating ultraviolet light. The invisible ink may also be infrared absorbing ink. The infrared absorbing ink can be visualized by a night vision device. Furthermore, the security print may be one in which multiple regions of nematic liquid crystals with different orientations are formed for each region. This is a nematic liquid crystal security print. This can be visualized with a polarizing plate. The security print can be formed by gravure printing, gravure offset printing, or screen printing. In other words, the concealment code 22 is formed by at least one of a hologram film that exhibits a special visual effect under specific viewing conditions and a security print having a special visual effect. The hidden code 22 has the special visual effect described above, which allows the authenticity of the display on which the hidden code 22 is formed to be verified. This verification of authenticity is either OVART or COVERT verification.

[0020] In this embodiment, the concealment code 22 is either the character string "DOME" or "INTE." "DOME" stands for "Domestic" and indicates that the owner has the nationality of the country in which the display object 100 is used (JAPAN in the example of FIG. 1). "INTE" stands for "International" and indicates that the owner has a nationality other than the country in which the display object 100 is used (JAPAN in the example of FIG. 1). The concealment code 22 may be any code that allows the country in which the display object 100 is used and the nationality of the owner to be distinguished, and is not limited to the above-mentioned pair of "DOME" and "INTE." In this example, the concealment code 22 is information that encodes part of the personal information related to the owner of the display 100. The encoded information is a three-letter country code defined in ISO3166-1 alpha-3, a two-letter country code defined in ISO3166-1 alpha-2, a three-digit country code defined in ISO3166-1 numeric, or the like. Alternatively, it is a country code based on the IOC code defined by the International Olympic Committee.

[0021] The concealment code 22 is not limited to information indicating the nationality of the owner of the display object 100. For example, the concealment code 22 may be a region code assigned to a prefecture or state as defined by ISO3166-2, a gender code as defined by ISO5218, a currency code as defined by ISO4217, a language code as defined by ISO639, etc. The concealment code 22 may also be a uniquely defined code. The concealment code 22 is information that belongs to or can distinguish the owner of the display body 100, and may be associated with the identification information 21 of the owner. The concealment code 22 may be the above-mentioned various codes as it is, or may be a hash value generated by a hash function from at least one of the above-mentioned various codes or the code and image of the identification information. The hash function is preferably a cryptographic hash function. That is, the concealment code 22 is preferably a hash value generated by a cryptographic hash function. The cryptographic hash function can be defined as one that is preimage-resistant, second preimage-resistant, and highly collision-resistant. This hash function may be a Merkle-Damgard construction (the a after Damgard is a lowercase A with a ring above). This allows hash values ​​to be easily generated even when the identification information 21 and the concealment code 22 are variable length. The applicable hash function that generates a hash value may be any one of MD5, SHA-244, and SHA-256, or a hybrid thereof. It is preferable that the hash value generated by the hash function is of a fixed length. By making it of a fixed length, the code of the concealment code 22 can be recorded in a certain area. In this case, the value input to the hash function may be of a fixed length or of a variable length.

[0022] In generating the ciphertext and concealment code, the encrypted code may be used as the code generated using the hash function described above. The encryption code can generate ciphertext or hidden code using public key cryptography, symmetric key cryptography, or hybrid cryptography.

[0023] When public key cryptography is used to generate a ciphertext from identification information using a private key and record the ciphertext as an encrypted code in the third area, the authentication and verification of the authenticity of the display body 100 can be performed offline, as described below. The authenticity of the display body can be verified offline by storing a public key in the memory of a device or application that authenticates the display body 100 and decrypting the ciphertext using the stored public key. Note that when public key cryptography is used, it may be used not only for offline verification but also for online verification. More specifically, the authenticity of the display body can be verified by encrypting all of the identification information with a private key to generate a code, recording the generated code in a third area, decrypting the code with a public key, and checking whether the code is identical to the identification information and the concealment code. Also, the authenticity of the display body can be verified by encrypting a hash value generated from the identification information using a hash function with a private key to generate a code, recording the generated code in a third area, decrypting the code with a public key, and checking whether the code is identical to the hash value generated by the hash function of the identification information and the concealment code. Verification of the authenticity of the display body based on whether the information obtained by decrypting the ciphertext is identical to the identification information and the concealment code may be a forensic verification. Applicable public key cryptography is either RSA or elliptic curve cryptography, or a hybrid thereof. The public key cryptography may also be lattice cryptography. The key length of the public key is preferably 1024 bits, 2048 bits, 3072 bits, or 4096 bits. The key length can be selected depending on the level of security required for the display.

[0024] Furthermore, when a ciphertext or a concealment code is generated using a common key cryptosystem, this can be used for online verification, which will be described later, to authenticate and verify the authenticity of the display 100. Also, when a ciphertext or a concealment code is generated using a hybrid cryptosystem, this can be used for online verification, which will be described later, to authenticate and verify the authenticity of the display 100. A block cipher, a stream cipher, or a hybrid of these can be applied as the common key method. Applicable block ciphers are AES, Camellia, or a hybrid of these. Applicable stream cipher is RC4. The key length may be 128 bits, 192 bits, or 256 bits.

[0025] The ciphertext 25 in this embodiment is configured by combining a hash value "A" of at least one of the code and image of the identification information 21, a character string "012345" obtained by encrypting the code of the identification information 21, and the Japanese code "JPN" in ISO3166-1 alpha-3. The ciphertext 25 may include a character length. The ciphertext 25 may also be obtained by encrypting the code of the identification information 21. This allows the authenticity to be verified based on whether the code obtained by decrypting the ciphertext is the same as the code of the identification information 21. The ciphertext may also be obtained by encrypting the recorded concealment code 22. In this case, the recorded concealment code 22 may be a hash value of the identification information 21. In particular, by making this hash value generated from a cryptographic hash function, it is easy to prevent spoofing. When the recorded concealment code 22 is of fixed length, the encrypted code can also be of fixed length. In this case, it is easy to implement an encryption program and a decryption program. A hologram film is thermally transferred to the third region 13, and the ciphertext 25 is recorded as a hologram structure of the hologram film and is displayed as a hologram reconstruction image. As shown in Fig. 2A and Fig. 2B, the hologram reconstruction image of the ciphertext 25 is visually recognized as being located within a reconstruction image space 26 that is separated from the substrate 30 in the normal direction Z of the display body 100. In the example shown in Fig. 2A and Fig. 2B, the reconstruction images 27A of "A", "J", "P", "N", "3", "4", and "5" are formed in the reconstruction image space 26 on the upper side (Z>0) of the substrate 30, and the reconstruction images 27B of "0", "1", and "2" are formed in the reconstruction image space 26 on the lower side (Z<0) of the substrate 30. The holographic reconstruction image of the ciphertext 25 can be obtained by a display observation method and a detection device, which will be described later.

[0026] As shown in FIG. 2B, the reconstructed images 27A and 27B are formed at a plurality of positions with different distances from the substrate 30 in the normal direction Z, but the distances from the substrate 30 may be uniform. The distance between the reconstructed image and the substrate 30 may constitute a part of the ciphertext 25. That is, the ciphertext 25 may include a code obtained by encrypting the identification information 21 and information on the distance between the hologram reconstructed image of this code and the substrate 30. It is preferable that the distance between the hologram reconstructed image and the substrate 30 is quantized and discrete. The ciphertext 25 may be recorded by laser engraving or inkjet printing. The ciphertext may be recorded as a one-dimensional code or a two-dimensional code. In this way, reading by a reader becomes easy. An applicable one-dimensional code is a barcode. An applicable two-dimensional code is a QR code (registered trademark). The ciphertext may be recorded in an IC chip built into the display body. The display body may have a contact terminal on the surface thereof, and the built-in IC chip may be connected to the contact terminal on the surface of the display body. The display may also have an antenna built in, and the built-in IC chip may be connected to the antenna. The IC chip built in the display may be capable of authentication by itself. This allows electronic authentication. The display with the built-in antenna and IC chip can also be used as RFID.

[0027] The second region 12 also has a holographic structure, and a hidden code 22 is displayed as a holographic reconstructed image. 4A and 4B show the reconstructed positions of the hologram reconstructed image of the concealment code 22. The reconstructed images 24 are all formed above the substrate 30 within the reconstructed image space 23. The distance between the substrate 30 and the reconstructed image corresponding to each character is either distance z1 or z2, which is shorter than distance z1, but may all be different. The distance between the reconstructed image and the substrate 30 may form part of the concealment code 22. In other words, the concealment code 22 may include characters that encode part of personal information and information on the distance between the hologram reconstructed image of the character and the substrate 30. By quantizing this distance, it is possible to make it discrete and record the information as digital data.

[0028] The distance between the reconstructed image and the substrate can be appropriately set depending on the hologram structure. The hologram structure formed in the second region 12 and the third region 13 may be a Lippmann-type volume hologram or a hologram structure having a fine concave-convex structure. The hologram structure having a concave-convex structure may be a computer-generated hologram structure in which a reconstructed image is designed in advance and a diffraction grating hologram pattern is calculated from the designed reconstructed image. These hologram structures can be formed in a film shape with optical phase information for forming the reconstructed image as a fine concave-convex structure. In addition, the positions of the reconstructed image 24 of the concealment code and the reconstructed images 27A and 27B of the ciphertext can be precisely controlled.

[0029] When a Lippmann volume hologram is used in the hologram structure, a photoresponsive photopolymer is irradiated with object light from the concealment code or cipher text to be formed and a reference light for reproducing the object light, and the interference fringes are recorded in the photopolymer to form the hologram structure. The optical phase information of the object light from the concealment code or cipher text may be calculated in advance by a computer, the optical phase information may be displayed by a spatial light phase modulator, and the light transmitted through or reflected by the spatial light phase modulator may be used as the object light to form a Lippmann volume hologram. The material of the volume hologram may be a photopolymer whose refractive index is modulated by exposure to light. The type of photopolymer may be a photocrosslinking type or a photopolymerization type. An example of the photocrosslinking type is one whose main component is polyvinylcarbazole. The photopolymerization type is easy to achieve high sensitivity due to a chain reaction during exposure to light. The photocrosslinking type is easy to increase the refractive index difference. The photopolymerization type may be a wet type that requires development processing, or a dry type that does not require development processing. The dry photopolymer may use a pair of materials with different refractive indexes and low compatibility as the main component. An example of the main component pair is a vinyl acetate compound and an acrylic acid ester compound, or an epoxy compound and an acrylic acid ester compound, and one of these may be a polymer. A photopolymer whose main component pair is a vinyl acetate compound and an acrylic acid ester compound is easy to create a refractive index difference. A photopolymer whose main component pair is an epoxy compound and an acrylic acid ester compound is easy to increase durability. An example of the wet type is a mixture of polyvinylpyrrolidone and a monomer. This mixture tends to increase the refractive index difference because the parts with weak light intensity dissolve in the developer and become voids. Volume holograms can be replicated by irradiating a master hologram with a laser, exposing a photopolymer to the interference fringes of the reflected light (object light) and the irradiated laser light (reference light), and modulating the refractive index of the photopolymer. (Contact copy method)

[0030] When a computer-generated hologram is used in a hologram structure, optical phase information for recording a hidden code or encrypted message is calculated in advance by a computer, and a fine relief structure for realizing the optical phase information is formed by a laser drawing method, an electron beam drawing method, an ion beam drawing method, or the like. The fine relief structure is then used as a master to be pressed against a film material coated with a thermoplastic resin, a thermosetting resin, or a photosetting resin to replicate the structure, thereby obtaining a hologram film.

[0031] The fine uneven structure may have the fine uneven structure described below and disclosed in PCT / JP2017 / 020049 (International Publication WO2017 / 209113A1). As an example, the fine concave-convex structure of the present embodiment has a phase angle recorded region and a phase angle non-recorded region. In the fine concave-convex structure, a region other than the phase angle recorded region is a phase angle non-recorded region. In one example, the phase angle non-recorded region is a mirror surface.

[0032] Here, the positional relationship of each component will be described using an XYZ orthogonal coordinate system. The fine concave-convex structure is disposed along the XY plane. When light is incident from a direction intersecting the fine concave-convex structure, the incident light is modulated by the fine concave-convex structure to obtain a reconstructed image. The reconstructed image is an image of multiple reconstruction points. The reconstruction points are obtained at positions spaced apart from the fine concave-convex structure in the Z direction. When the fine concave-convex structure is viewed from a reconstruction point of interest, the range in the viewing angle direction in which the reconstructed image is reproduced is called the viewing angle θ. In the following explanation, the viewing angle direction is the X direction or the Y direction. On the fine concave-convex structure, the computational element sections are defined according to the viewing angle θ from each reconstruction point where the reconstruction image is reproduced. In this manner, the computational element sections are defined independently of the phase angle recording region and the phase angle non-recording region, and therefore usually overlap with the phase angle recording region and the phase angle non-recording region, respectively.

[0033] In addition, there are a plurality of regeneration points, and therefore there are the same number of computational element partitions as the number of regeneration points, corresponding to each of the plurality of regeneration points. The reproduction point is disposed at a distance from the fine concave-convex structure. The reproduction point is preferably reproduced at a distance of 5 mm or more and 25 mm or less from the fine concave-convex structure in the Z direction. The reproduction point may be reproduced on the observer side from the fine concave-convex structure, or on the opposite side of the fine concave-convex structure from the observer. In either case, the distance of the reproduction point from the fine concave-convex structure can be specified in the same way.

[0034] The viewing angle θ from the reproduction point is defined by the following equation (1). θ<(A / m) (1) Here, if (λ / 2d)≦1, A=asin(λ / 2d), λ is the wavelength of light, d is the arrangement interval of the unit blocks in the viewing angle direction, and m is a real number of 3 or more. Specifically, the wavelength of light λ is 555 nm, which is the maximum relative luminosity of humans among visible light. The arrangement interval d can be the center-to-center distance between the unit blocks. The arrangement interval of the central unit blocks is 10 nm or more and 200 nm or less. The viewing angle θ is determined by the range in the X direction when the fine concave-convex structure is viewed from a focused reproduction point, and is 1 / 2 the angle 2θ formed by the minimum value Xmin in the X direction, the focused reproduction point, and the maximum value Xmax in the X direction. Note that the X direction and the Y direction correspond to the X coordinate axis and the Y coordinate axis of the Euclidean coordinate system, respectively, in which the direction in which the fine concave-convex structure extends is the X direction, and the direction perpendicular to the X direction is the Y direction.

[0035] The viewing angle θ when the viewing angle direction is the Y direction is similarly defined. That is, the viewing angle θ is determined by the range in the Y direction when the fine uneven structure is viewed from the reproduction point of interest, and is 1 / 2 the angle 2θ formed by the minimum value Ymin in the Y direction, the reproduction point of interest, and the maximum value Ymax in the Y direction. Therefore, the arrangement interval d of the unit blocks corresponds to the arrangement interval dx of the unit blocks in the X direction when the viewing angle direction is the X direction, and corresponds to the arrangement interval dy of the unit blocks in the Y direction when the viewing angle direction is the Y direction.

[0036] For this reason, the computational element partition is generally a square or a rectangle. However, the computational element partition may be a polygon other than a rectangle, or a circle or an ellipse. As for polygons, in addition to squares and rectangles, hexagons are also suitable. When the computational element partition is other than a square or rectangle, the minimum value (lower limit value) of the computational element partition in the X direction is set to Xmin, and the maximum value (upper limit value) of the computational element partition in the X direction is set to Xmax. Similarly, the minimum value of the computational element partition in the Y direction is set to Ymin, and the maximum value of the computational element partition 16 in the Y direction is set to Ymax.

[0037] When the shape of the unit block is a square or a rectangle, the corners of the square or rectangle are actually rounded to form a rounded rectangle. The unit block may be fused with an adjacent unit block. In this case, even if the shape of each unit block is a rounded rectangle, the shape of the fused unit blocks is not a rounded rectangle and is deformed, but the optical effect does not change even if the unit blocks are deformed by fusion. The unit blocks are preferably arranged in an orderly manner. The orderly arrangement can be an arrangement at intervals within a certain range or an arrangement at equal intervals. Typical orderly arrangements are a square arrangement and a hexagonal arrangement.

[0038] As can be seen from the above formula (1), the viewing angle θ is less than A. When light passes through this phase component and is diffracted, theoretically, diffraction beyond A does not occur. Therefore, when performing hologram calculation using a computer, the calculation range can be limited to the viewing angle θ as the upper limit. In this way, limiting the calculation range shortens the calculation time. Furthermore, even if calculation is performed for a range exceeding the viewing angle θ, it only calculates diffraction that does not theoretically exist, and the result only contributes as noise. However, in the above calculation, since calculation is not performed for a range exceeding the viewing angle θ, noise is not superimposed when the reproduced image at the reproduction point is reproduced.

[0039] Each of the phase angle recording area and the phase angle non-recording area includes a plurality of unit blocks. For unit blocks included in an area (overlapping area) of the phase angle recording area that overlaps with the calculation element partition, a phase angle is calculated by a computer based on the phase component, and the calculated phase angle is recorded in the corresponding unit block included in the overlapping area.

[0040] The fine relief structure of this embodiment is visible and can be recognized. When an optical structure having such a fine relief structure as a relief structure is tilted by a certain angle or more and observed from outside the range of the viewing angle θ, the reconstructed image disappears due to the relief structure. In addition, the reconstructed image is only reconstructed with a point light source, so the reconstructed image disappears under diffuse illumination. The viewing angle θ is preferably 5 degrees or more from the viewpoint of visibility of the reconstructed image, and is preferably 15 degrees or less from the viewpoint of making the reconstructed point easily disappear.

[0041] A hologram structure having a fine concave-convex structure can be formed by using a concave-convex structure formed by a laser or an electron beam as a resist plate, electroforming the resist plate into a nickel stamper, and embossing the stamper into a resin. This hologram structure can be formed into a hologram transfer foil to obtain a hologram transfer foil on which the hologram structure is formed. By thermally transferring this hologram transfer foil, a hologram film on which the hologram structure is formed can be arranged in each region. A metal reflective layer may be formed on the fine relief hologram structure. The metal of the reflective layer is aluminum (Al), gold (Au), silver (Ag), chromium (Cr), nickel (Ni), or an alloy of these. This improves the brightness of the reconstructed image reproduced by the fine relief hologram structure formed on the hologram film. This makes the reconstructed image of the hidden code or cipher text brighter, making it easier to verify. The fine relief hologram structure is called a relief hologram.

[0042] A reflective layer of a metal compound may be formed on the hologram film on which the hologram structure of the fine relief structure is formed. The metal compound may be a metal sulfide or a metal oxide. An applicable metal sulfide may be zinc sulfide. An applicable metal oxide is titanium dioxide, zirconia, zinc sulfide, or aluminum oxide. The reflective layer of the metal compound has optical transparency. By forming the reflective layer with optical transparency, even if the second region 12 is formed on the first region on which the identification information 21 is formed, the identification information 21 below the second region 12 can be visually recognized. The metallic or metal oxide reflective layer can be formed by physical deposition. Applicable physical deposition methods are vacuum evaporation and sputtering. The metal oxide reflective layer can also be formed by chemical deposition. The reflective layer can also be formed by wet coating techniques such as the sol-gel method.

[0043] In the display body 100, the second region 12 and the third region 13 may be disposed anywhere as long as they are visible in a plan view. The second region 12 and the third region 13 may be disposed at different positions. As shown in FIG. 5A, when the second region 12 and the third region 13 are disposed inside the base material 30, in order to tamper with the second region or the third region, the base material 30 itself must be destroyed. This leads to prevention of tampering and improves the anti-counterfeiting performance. The configuration shown in FIG. 5A can be formed, for example, by forming or attaching the second region 12 and the third region 13 in advance to multiple resin sheets for forming the base material 30, and then integrating these resin sheets by hot-press lamination with the second region 12 and the third region 13 facing the other resin sheets.

[0044] As shown in FIG. 5B, when the second region 12 and the third region 13 are arranged on the surface of the substrate 30, the second region 12 and the third region 13 including the owner information of the owner of the display body 100 can be continuously formed after the substrate 30 is formed, so that the manufacturing efficiency of the display body 100 can be improved. In this case, the first region 11 may be arranged on the surface of the substrate 30. Alternatively, a display body in which the second region 12 is formed in advance on the substrate 30 may be selected according to the identification information. This can improve the productivity of the display body. Alternatively, the third region 13 may be provided on the back surface. 5B, an adhesive material may be disposed on the substrate 30, and the medium to become the second region 12 and the third region 13 may be attached onto the substrate 30. Alternatively, an adhesive layer may be provided on the medium to become the second region 12 and the third region 13, and the medium may be attached onto the substrate 30.

[0045] 5C, the intermediate transfer foil 31 on which the second region 12 or the third region 13 is formed may be attached to the substrate 30 to form the display member 100. In this case, the intermediate transfer foil 31 and the substrate 30 are bonded to each other over their entire surfaces, so that the second region 12 and the third region 13 are in stable contact with each other and are unlikely to peel off.

[0046] A method for manufacturing the display 100 will be described. Although the basic shape and appearance of the display 100 are the same, the recorded identification information 21 and the contents of the cipher text 25 differ from one another. Therefore, in order to manufacture one display, it is necessary to prepare individual information to be recorded each time. Also, the concealment code 22 is not the same for each card.

[0047] FIG. 6 shows an example of a process flow for manufacturing the display 100. First, in step S200, the identification information 21 is acquired. For example, in a passport issuing device, an ID card issuing device, or the like, step S200 is executed by selecting and inputting individual information related to a user to whom the display body 100 is to be issued. At this time, at least one of a code and an image of the identification information 21 is also generated. By preparing an input form or format in advance, it is possible to easily acquire and recognize the identification information.

[0048] In step S201, a concealment code 22 is generated from at least one of the code and the image of the identification information 21 acquired in step S200. In step S202, at least one of the code of the identification information and the concealment code is encrypted to generate ciphertext 25. When the ciphertext 25 is decrypted, it becomes identical to a part or all of at least one of the code of the identification information and the concealment code. In other words, the ciphertext 25 is associated with at least one of the code of the identification information and the concealment code.

[0049] In step S203, at least one of a code and an image of the identification information 21 is formed in the first region 11 of the display body 100. As described above, the formation is performed by at least one of thermal transfer and laser engraving. Alternatively, the formation may be performed by inkjet printing. In step S204, the concealment code 22 is formed in the second region 12 of the display 100. In step S205, the ciphertext 25 is recorded in the third area 13 of the display 100.

[0050] 6, either step S201 or step S202 may be performed first. Steps S203, S204, and S205 may be performed in any order or at any timing as long as they are performed after the corresponding individual information is acquired.

[0051] The flow shown in FIG. 7 shows an example of a procedure for manufacturing a display unit using a plurality of base materials prepared in advance. After the identification information is acquired in step S200, in step S210, one of the multiple substrates prepared in advance for producing the display body 100 is selected and acquired based on the acquired identification information. A concealment code that encodes a part of the identification information has already been formed in the second region of each of the multiple substrates. That is, the concealment code possessed by the multiple substrates is associated with a predetermined part of the identification information. For example, there can be illustrated a case where there are two types of substrates, "for Japanese people" and "for non-Japanese people", and the character string "DOME" is formed as a concealment code in the second region of the substrate for Japanese people, and the character string "INTE" is formed as a concealment code in the second region of the substrate for non-Japanese people. As a result, in step S210, the multiple substrates are selected and acquired in association with a part of the identification information, and a concealment code is formed in the second region. The subsequent steps are similar to those described in Fig. 6. Thus, the concealment code may be one of several patterns associated with a portion of the identification information.

[0052] FIG. 8A shows an embodiment of steps S204 and S205. FIG. 8A shows a hologram transfer foil 140 on which a plurality of information elements 150 are formed as a hologram structure. In steps S204 and S205, the hologram transfer foil 140 is positioned above the display body, and the information elements 150 corresponding to the content of the individual information to be recorded are selected and thermally transferred to the display body. In other words, as described above, the information elements 150 of the hologram structure 142 that match the positions of the cipher text 25, the characters of the concealed code 22, and the reproduced images of each character are selected and thermally transferred to the substrate 30 to form the information elements 150. Note that instead of directly thermally transferring the information elements 150 to the display body 100, they may be thermally transferred to the intermediate transfer foil 31 described above. The code of the cipher text 25 and the concealed code 22 can be formed as character strings with different positions of reproduced images.

[0053] Fig. 8B is a cross-sectional view taken along line II in Fig. 8A. A plurality of identical information elements 150 are formed on the hologram transfer foil 140, but the positions of the reconstructed images 170 of the plurality of information elements 150 are different from one another, as shown in Fig. 8B. Therefore, individual information including a plurality of identical information elements can be formed by varying the positions of the reconstructed images. This makes it possible to significantly increase the amount of information that can be included in the concealment code and ciphertext. For example, when forming three digits from 0 to 9, the number of combinations is 10 to the power of 3 (1,000 ways), but by combining the positions of the reconstructed images, the number of selectable combinations increases. For example, as shown in Figure 8B, if there are five patterns for the positions of the reconstructed images, the number of combinations is 50 to the power of 3 (125,000 ways), which is 125 times the number of combinations. The number of combinations can be further increased by including not only numbers but also letters and symbols such as the alphabet. This makes it possible to reduce the number of information elements required for the concealment code 22 and the ciphertext 25, thereby enabling greater freedom in the layout of the display body and improving manufacturing efficiency.

[0054] 9A and 9B show a method for forming only desired information elements 150 on a substrate 30 from a hologram transfer foil 140. FIG. As shown in Fig. 9A, the hologram transfer foil 140 includes a carrier film 141 and a hologram structure 142 formed on the carrier film 141. With respect to this hologram transfer foil 140, an energy application unit 60 is brought into contact with the position of a desired information element 150 on the carrier film 141, and external energy is applied to the information element 150. When an adhesive layer provided on the hologram structure 142 is activated by the external energy, the adhesive layer is bonded to the substrate 30, and only the desired information element 150 is thermally transferred to the substrate 30, as shown in Fig. 9B. The energy applying unit 60 may be a heat head or a laser head. The heat head may be a die head having a shape to be thermally transferred or a thermal head.

[0055] As another example, information elements may be formed by partially removing a hologram film that has been thermally transferred onto a substrate with a laser beam. For example, a hologram film having a shape of a seven-segment display may be thermally transferred onto a substrate, and predetermined segments may be removed to form numbers, alphabets, and the like. Furthermore, information elements may be formed by partially removing a hologram film selectively thermally transferred from a hologram transfer foil with a laser beam.

[0056] A method for reading information from the display 100 will now be described. At least one of the code and image of the identification information 21 recorded on the display 100 can be made visible. Also, at least one of the code and image of the identification information 21 recorded on the display 100 can be made readable by a reading device. When reading the recorded concealment code 22 and ciphertext 25, the conditions for reading the concealment code 22 and ciphertext 25 (light source information, light source and reading spectrum, reproduction position of the reproduced image to be read, etc.) are obtained, and all or part of the concealment code 22 and ciphertext 25 can be obtained based on the conditions.

[0057] When reading, the information conversion program or encryption process used when generating the ciphertext 25 from the code of the identification information 21 or the concealment code 22 may be used. Alternatively, the read condition may be included in at least one of the code of the identification information 21 and the concealment code 22. Furthermore, the ciphertext 25 may include the read condition. In order to obtain a reconstructed image of the hologram structure formed in the second area 12 and the third area 13, a point light source corresponding to a predetermined reference light or a laser light source is required. The point light source may be an LED light source. The readout condition may include information on the type of the light source.

[0058] Based on the information read from the display 100, the authenticity of the display can be verified. When the observation device used to verify authenticity is connected to a network, it is possible to verify whether the display object is authentic by checking the combination of the acquired identification information 21, concealment code 22, and cipher text 25 against a server, database, etc. connected to the network. In other words, it is possible to verify whether the acquired identification information 21, concealment code 22, and cipher text 25 match by checking against a server, database, etc. connected to the network. Alternatively, the identification information 21 acquired by the observation device may be transmitted to a server or database via a network and collated, so that the observation device receives and acquires the read conditions for the concealment code 22 and the ciphertext 25. After that, the authenticity can be verified by adapting the acquired concealment code 22 and the ciphertext 25 according to the read conditions. In this case, the read conditions for the concealment code 22 and the ciphertext 25 used for authenticity verification can be changed each time verification is performed, thereby further improving security.

[0059] If the observation device is not connected to a network, the combination of the identification information 21, the concealment code 22, and the ciphertext 25 may be stored in the observation device and the matching may be performed in the observation device. However, in this case, if the number of combinations becomes huge, the matching may take a long time or the observation device may not be able to store all of them. In addition, the maintenance of the database becomes cumbersome because it must be performed for each observation device.

[0060] In such a case, by previously associating the contents of the identification information with the reading conditions of the concealment code 22, it is possible to omit obtaining the reading conditions and shorten the time required to verify the authenticity. Fig. 10 shows a flow chart of an example of such a method for verifying authenticity. In the display according to this example, a three-letter country code based on ISO3166-1 alpha-3 is included in the identification information. The concealment code has a hologram structure in which the same country code is reproduced, and the reproduced image of the three-letter information element is set at one of three positions Z1, Z2, and Z3, each of which is at a different distance from the substrate surface.

[0061] First, in step S301, the observation device reads the code of the identification information 21 in the first area 11 and obtains the country code. Next, in step S302, the observation device refers to the stored table and acquires, as the reading conditions, the reading positions of the reconstructed images of the characters corresponding to the acquired country code. An example of the table is shown in Table 1.

[0062] [Table 1]

[0063] In step S303, the observation device obtains a reconstructed image in the second region according to the readout conditions obtained in step S302, and sets the reconstructed image as the concealment code 22. For example, if the country code acquired in step S301 is "IRL," then in step S302, the read conditions of "first character Z1, second character Z1, third character Z2" are acquired based on Table 1. Then, in step S303, the observation device acquires a reconstructed image at a position specified in the read conditions. If the display body is genuine, the reconstructed image of each character is acquired normally, but in the case of a counterfeit product in which all reconstructed images are located at Z1, the reconstructed image of the third character is not acquired, and the concealment code is incomplete.

[0064] After the ciphertext is acquired in step S304, in step S305, whether the combination of the acquired identification information, concealment code, and ciphertext is appropriate, in other words, whether they match, is compared with the information stored in the observation device to determine whether the display object is genuine. In the above case, since the concealment code of the counterfeit product is incomplete, consisting of only the two characters "IR," it can be determined that the display object is not genuine. The determination in step S304 can be performed either online or offline. In the case of online, for example, the acquired identification information, concealment code, and cipher text are transmitted from the observation device to a server or database via a network, and it can be confirmed on the server or database whether the combination of the identification information, concealment code, and cipher text is appropriate, in other words, whether they match. In the case of offline, a list of country names and country codes as shown in Table 1 is recorded in the observation device. First, the observation device acquires nationality as identification information from the display body, and based on the acquired nationality information, the observation device acquires the reading position of each character of the country code from the list. After that, the observation device reads and acquires the country code as the concealment code from the display body, and by comparing the acquired concealment code with the list, it is possible to check whether the identification information and the concealment code match. In addition, the authenticity of the display body can be verified based on whether the data obtained by decrypting the cipher text is the same as the whole or part of at least one of the code of the identification information and the concealment code. In addition, the authenticity of the display body may be verified based on whether the data obtained by decrypting the cipher text is the same as the concealment code. In this decryption, if the public key cryptosystem is used, a public key is used, and if the common key cryptosystem is used, a common key is used. In addition, in the case of a hybrid of these, a public key and a common key are used. Forensic verification is performed in step S304. Since the hidden code is recorded by a hologram film or security printing, it is difficult to tamper with it. In addition, since an encryption algorithm and an encryption key are required to match the hidden code with the ciphertext, two-factor verification is possible using the possessed information and the encryption. The decryption key may include the owner's PIN. In addition, when encrypting the ciphertext, it may be encrypted twice, using both an encryption using a specific encryption key and an encryption using the owner's PIN. The encryption method using the owner's PIN can be a common key method. In this way, the display body 100 is capable of a high level of authentication. In addition, when an image of the owner's identification information is formed on the display body 100, the image can be compared with the owner. In particular, when a face image is formed as the image, it is easy to compare the owner with the display body 100.Furthermore, when a facial image is formed using a hologram, it is possible to prevent impersonation since it is difficult to compare the owner with the display 100 and to counterfeit the facial image itself.

[0065] An observation device suitable for observing the display body of this embodiment will be described. The observation device is a reader that reads a code. Observation device 400 shown in Fig. 11A is an observation device of a type in which the display body 100 is inserted and read. Observation device 410 shown in Fig. 11B is an observation device of a type in which the display body 100 is placed on a scanner surface 411 and read.

[0066] The observation device 400 includes an optical sensor 401 for acquiring a reconstructed image of the concealment code 22 and the cipher text 25. The observation device 410 includes an optical sensor 413 for acquiring a reconstructed image of the concealment code 22 and the cipher text 25. The optical sensors 401 and 413 are configured to be movable within the observation device, and can be moved to positions corresponding to the second area 12 and the third area 13. The observation device may be provided with a plurality of optical sensors, and the second area 12 and the third area 13 may be read by dedicated optical sensors, respectively.

[0067] The observation device 410 is equipped with a line scanner 412 for acquiring the identification information 21, so that by placing the display 100 on the scanner surface 411 and operating it, it is possible to acquire all of the identification information 21, the concealment code 22, and the ciphertext 25 at once.

[0068] The display of the present invention will be further explained using experimental examples. (Experimental Example) A hologram structure was calculated using a computer-generated hologram so that the three letters "A," "B," and "C" were reproduced at positions 5 mm, 7 mm, and 9 mm from the front side of the hologram film interface, respectively, and a hologram transfer foil was produced with the hologram structure embossed. Green light was used as the reference light.

[0069] The produced hologram transfer foil was thermally transferred onto a polycarbonate resin sheet, and a plurality of polycarbonate resin sheets were stacked together and thermally laminated to produce a pre-display body having a substrate with a hologram film embedded therein as a concealment code.

[0070] Laser engraving was performed on the pre-display using an infrared laser beam with a wavelength of 1064 nm, and two displays were produced, each with the identification information of person A and person B. The read conditions for the hidden code on display A, which recorded person A's information, were "red light source, playback position 9 mm," and the read conditions for the hidden code on display B, which recorded person B's information, were "green light source, playback position 7 mm."

[0071] We created an observation device that combines a full-color LED light source, an optical prism, and a CMOS sensor, in which the light from the light source is incident perpendicularly on the display and the reconstructed image of the holographic film is focused on the CMOS sensor.

[0072] When the observation device was used to obtain the hidden code according to the reading conditions, the hidden code was not obtained from display A. This was because the light became red, changing the position of the reconstructed image of each character, and the reconstructed image at the 9 mm position disappeared. On the other hand, in the case of display body B, only the reconstructed image of “B” located at 7 mm was obtained.

[0073] When the second area of ​​the display bodies A and B is viewed with the naked eye, the reconstructed images of all of "A", "B", and "C" can be seen. Therefore, a person who would attempt to counterfeit or tamper with the display cannot know whether all of "A", "B", and "C" will be used to verify the authenticity, or whether only some of them will be used. In addition, if the above-mentioned read conditions change, the reconstructed image acquired by the observation device also changes, so unless the correct read conditions are known, it is impossible to create a counterfeit that can withstand verification of the authenticity. This experimental example demonstrated that a concealment code can be suitably formed using a hologram structure with different reproduction positions, and that a ciphertext can be suitably recorded as a code.

[0074] Although one embodiment of the present invention and examples have been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and configuration changes and combinations within the scope that do not deviate from the gist of the present invention are also included. Moreover, the scope of the present disclosure is not limited to the embodiments shown and described, but includes all embodiments that achieve equivalent effects to those of the object of the present invention. Moreover, the scope of the present disclosure is not limited to the features of the invention defined by the claims, but includes each and every disclosed feature and any combination of such features.

[0075] The terms "part," "element," "region," "area," "layer," "surface," "display," "article," "recording," "medium," "substrate," "printing," and "engraving" used in this disclosure are physical entities. A physical entity can refer to a material form or a spatial form surrounded by a material. A physical entity can be characterized by its material, physical properties, physical quantities, psychophysical quantities, arrangement, shape, external appearance, the aforementioned statistics, recorded information, recorded data, recorded codes, readable information, readable data, readable codes, capabilities, performance, appearance, color, spectrum, images formed / displayed, processing methods, detection methods, verification methods, and judgment methods. In addition, a physical entity can have a specific function depending on the characteristics of the physical entity. A set of physical entities having a specific function can exhibit a synergistic effect due to each function of each physical entity.

[0076] When interpreting terms, configurations, features, aspects, and embodiments, reference should be made to the drawings as necessary. Matters that can be directly and unambiguously derived from the drawings should be the basis for amendment in the same manner as the text.

[0077] The terms used in this disclosure and particularly in the claims are generally intended as "open" terms (e.g., the term "having" should be interpreted as "having at least," the term "including" should be interpreted as "including but not limited to," etc.). Furthermore, no specific number is intended unless a specific number is explicitly recited in the claims. For example, to aid in understanding, the claims may include the use of the introductory phrases "at least one" and "one or more" to introduce the enumeration of claims. However, the use of such phrases should not be interpreted as limiting a particular claim, including a claim introducing a recitation with the indefinite article "a" or "an," to an embodiment containing only one such recitation. The phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" should be interpreted as meaning at least ("one" or "one or more"). [Industrial Applicability]

[0078] The above-mentioned display body can be used as an optical effect for preventing counterfeiting, as well as a reading device and a method for verifying authenticity, since the individual information obtained during visual observation by a person and the individual information obtained by a reading device can be the same or different. In particular, it can be used as a display body for protecting the value and information contained in items such as personal authentication media such as passports, driver's licenses, and ID cards, in which individual information is used. In addition, since there is individual information that can be obtained only through a reading device, it can also be used in a machine authentication system linked to personal information and individual information. The display of the present invention has a simple structure and can effectively prevent tampering and counterfeiting. [Explanation of symbols]

[0079] 11 First area 12 Second area 13 Third area 21 Identification information 22 Hidden Code 25 Ciphertext 30 Base material 100 represents body

Claims

1. generating a concealment code from the identifying information; encrypting the concealment code to generate a ciphertext; forming at least one of a code and an image of the identification information on a substrate by at least one of thermal transfer and laser engraving; forming the concealment code on the substrate by thermal transfer or security printing; recording the cryptogram on the substrate by at least one of thermal transfer and laser engraving; In a method for producing a display body including the substrate, The concealment code is formed by applying external energy to a hologram transfer foil having a hologram structure to thermally transfer a hologram film to the base material, A method for manufacturing a display in which the hologram structure is transferred multiple times, and the position of at least one reconstructed image of the hologram structure in the thickness direction of the substrate is different from the position of the at least one reconstructed image on the surface of the substrate, and is different from the positions of the other reconstructed images in the thickness direction of the substrate.

2. Obtaining an identification code and a concealment code; encrypting at least one of the identification information code and the concealment code to generate a ciphertext; forming at least one of the code and image of the identification information on a substrate by at least one of thermal transfer and laser engraving; The concealment code is formed on a substrate by transfer printing or security printing, recording said cryptogram on a substrate by at least one of transfer printing and laser engraving; In a method for manufacturing a display body, The concealment code is formed by applying external energy to a hologram transfer foil having a hologram structure to thermally transfer a hologram film to the base material, A method for manufacturing a display in which the hologram structure is transferred multiple times, and the position of at least one reconstructed image of the hologram structure in the thickness direction of the substrate is different from the position of the at least one reconstructed image on the surface of the substrate, and is different from the positions of the other reconstructed images in the thickness direction of the substrate.

3. The identification information is formed by applying external energy to an information element having a holographic structure and thermally transferring it to the substrate. A method for producing the display according to claim 1 or 2.

4. A method for forming the ciphertext by thermally transferring an information element having a holographic structure onto an intermediate transfer foil, The intermediate transfer foil is bonded to the substrate. A method for producing the display according to claim 1 or 2.

5. Forming the ciphertext by thermally transferring an information element having a holographic structure onto an intermediate transfer foil; The intermediate transfer foil is bonded to the substrate. A method for producing the display according to claim 1 or 2.

6. A display comprising a substrate having a first region, a second region, and a third region, At least one of a code and an image of identification information is formed in the first area, A concealment code including information obtained by encoding at least a part of the identification information is formed in the second area, The encrypted ciphertext is recorded in the third area, the ciphertext is generated from at least one of the code of the identification information and the concealment code; At least one of the plurality of information elements constituting the concealment code or the ciphertext has a hologram structure, A plurality of the hologram structures are provided, Each of the reconstructed images of the plurality of hologram structures is located at a position spaced apart from the surface of the substrate, and the position of at least one of the reconstructed images of the plurality of hologram structures in the thickness direction of the substrate is different from the position of the other reconstructed images that are reconstructed at a different position on the surface of the substrate from the position of the at least one reconstructed image, and are different from the positions of the other reconstructed images in the thickness direction of the substrate. Display body.

7. The first region and at least one of the second region and the third region overlap in a planar view. The display according to claim 6.

8. The identification information is formed directly on the substrate. The display according to claim 6.

9. At least one of the multiple information elements constituting the concealment code or the ciphertext is directly formed on the substrate. The display according to claim 6.

10. The holographic structure is disposed within the substrate. The display according to claim 6.

11. The holographic structure is disposed on a surface of the substrate. The display according to claim 6.

12. The concealment code includes any of codes conforming to the international standard ISO having a country code, a geographic code, a gender code, a language code, and a currency code. The display according to claim 6.

13. The concealment code is disposed inside the substrate. The display according to claim 6.

14. A method for verifying the authenticity of the display of claim 6, comprising: Acquiring the identification information and the concealment code from the display; verifying whether the display body is authentic based on the acquired identification information and the concealment code; How to verify the authenticity of the display.

15. The method further comprises obtaining the ciphertext from the display; verifying whether the display object is authentic based on whether the acquired identification information and concealment code are identical to information decrypted from the ciphertext; A method for verifying the authenticity of an indicia according to claim 14.

16. The method further comprises obtaining the ciphertext from the display; verifying whether the display is authentic based on whether data decrypted from the ciphertext contains at least one of the acquired identification information and the acquired concealment code; A method for verifying the authenticity of an indicia according to claim 14.

17. The concealment code is recorded on a holographic film, A read condition for the concealment code is obtained from the obtained identification information; The concealment code is obtained according to the read condition. A method for verifying the authenticity of an indicia according to any one of claims 14 to 16.

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