JPH11180079A - Information recording medium and its certificating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an information recording medium difficult to be forged such as duplicating or the like with high security by disabling to visually recognize information recorded on a printed part and printing a visible pattern for the purpose of concealing or designing the medium. SOLUTION: The information recording medium comprises a releaf layer 1 recorded with a protrusion and recess pattern by a hologram or a diffraction grating recorded or represented with at least first pattern information, an at least infrared transmittance reflecting layer 2 provided on the layer 1, and an infrared absorption layer 4 provided behind the layer 2 and patterned according to second pattern information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium and an authentication method therefor, and more particularly to another information recording medium recorded in the form of a hologram or a diffraction grating in a pattern recognizable only by infrared rays. The present invention relates to an information recording medium on which the above information is arranged and an authentication method thereof.

[0002]

2. Description of the Related Art Heretofore, the present applicant has applied a method of forming visible light,
A reflective hologram or diffraction grating is provided by providing a transparent vapor-deposited reflective layer that can transmit infrared light, and an infrared-transmitting black concealment layer that transmits infrared light without transmitting visible light is provided below the hologram or diffraction grating. There has been proposed an information recording medium in which a printed portion of a machine readable information such as a bar code made of infrared-absorbing carbon black or the like is provided below the device (Japanese Patent Laid-Open No. 6-270884). The authenticity authentication of the information recording medium involves synchronizing and collating the recorded information of the hologram or diffraction grating read by visible light with the recorded information of the printing unit read by infrared light.

[0003]

However, in the case of an information recording medium such as a label in which the above-mentioned concealing layer is arranged, a substrate such as a card, a certificate, a passbook, a passport or the like on which such an information recording medium is attached is used. Because it is completely shielded, the appearance of the information recording medium part is poor, and there is no printed image from the beginning, and it is suspected that there is confidential information on the back side where the label is attached, so its security Was also inadequate.

[0004] Further, since the bar code or the like printed on the printing portion is usually formed by carbon black printing, even if the label is peeled off and the printed surface is peeled off, the printed surface remains on the substrate and can be visually recognized. However, there is a problem that copying is possible.

[0005] The present invention has been made in view of such problems of the prior art, and an object thereof is to prevent information recorded in a printing unit from being visually recognizable, and to blindfold or hide information in an information recording medium unit. An object of the present invention is to provide an information recording medium on which a visible pattern can be printed for the purpose of design, which has high security and is difficult to forge such as duplication, and an authentication method thereof.

[0006]

According to the present invention, there is provided an information recording medium comprising: a relief layer on which at least a hologram or diffraction grating on which first pattern information is recorded or expressed is recorded as an uneven pattern; It is characterized by comprising at least an infrared-transmissive reflective layer provided on the relief layer, and an infrared-absorbing layer provided behind the reflective layer and patterned according to second pattern information.

In this case, a bar code can be generated as a diffraction image from the relief layer. Also,
Desirably, the reflective layer is transparent to visible light. Part 1
An example is a germanium vapor deposition layer.

The infrared absorbing layer may be patterned by printing or may be patterned by laser marking after being uniformly applied.

On the reflection layer side of the infrared absorption layer or on the opposite side thereof, there is disposed a visible printing layer which is printed using ink which has only absorption and reflection characteristics in the visible light region and is reflective in the infrared region. May be.

According to the authentication method for an information recording medium of the present invention, a relief layer in which at least a first pattern information is recorded or expressed as a hologram or a diffraction grating is recorded as an uneven pattern, and the relief layer is provided on the relief layer. In an authentication method for an information recording medium comprising at least an infrared-transmissive reflective layer and an infrared-absorbing layer provided behind the reflective layer and patterned according to second pattern information, visible light diffracted light from the relief layer is Detected by a visible light detecting device, reads the first pattern information, illuminates infrared light through the relief layer and the reflective layer, and reflects light emitted through the infrared absorbing layer. Is detected by an infrared light detection device, the second pattern information is read, and a predetermined calculation is performed between the two read pattern information, Is a method which is characterized by identifying the information recording medium according to the result of.

In the present invention, a relief layer in which a hologram or a diffraction grating in which the first pattern information is recorded or expressed is recorded as a concavo-convex pattern, and at least an infrared-transmissive reflective layer provided on the layer. And the infrared absorbing layer provided behind the reflective layer and patterned according to the second pattern information, so that the first pattern information can be read by visible light, and the second pattern can be read by infrared light. The second pattern is not visually recognizable, and is forged by using two pieces of information.
Modification becomes difficult. In addition, a visible pattern can be printed for the purpose of blindfolding or design, so that security is further improved, and forgery such as duplication becomes difficult.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic principle of the information recording medium of the present invention is that the infrared transmitting black concealing layer of the information recording medium of JP-A-6-270884 is omitted, and instead, a hologram or a diffraction grating is provided below. An information recording medium is configured by providing an infrared absorbing layer patterned on machine-readable information such as a bar code, and reading recorded information of a hologram or a diffraction grating with visible light and reading recorded information of the infrared absorbing layer with infrared light. It is like that.

The basic structure of an information recording medium according to the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of one example of a card-shaped information recording medium according to the present invention, and shows a relief hologram or a relief diffraction grating pattern (hereinafter referred to as an optical diffraction pattern) from the side opposite to the card substrate 7. Is formed on the surface of the transparent resin layer 1 on which the irregular pattern is recorded, at least the infrared light, desirably both the infrared light and the visible light can be transmitted. A relief hologram or a relief diffraction grating 3 (hereinafter referred to as a light diffraction pattern relief layer 3) and a substantially red pattern provided on the transparent reflection layer 2 and patterned into machine-readable information such as a bar code. Infrared absorbing layer 4 that absorbs external light and does not absorb visible light, between transparent reflective layer 2 and infrared absorbing layer 4, or between infrared absorbing layer 4 and at least infrared light, preferably red Substrate 7 that reflects both light and visible light
(In the case of FIG. 1, between the infrared absorbing layer 4 and the substrate 7) and the adhesive layer 5 provided on the surface of the substrate 7 and reflecting without absorbing infrared light. The visible print layer 6 is laminated. The visible print layer 6 may be disposed on the light diffraction pattern relief layer 3 side of the infrared absorption layer 4.

[0015] With this configuration, the visible light causes the diffracted light from the light diffraction pattern relief layer 3 to be visible only at a specific light source position and an observation position. The printed pattern of the visible printing layer 6 is visible through the pattern relief layer 3 (when the transparent reflective layer 2 transmits only infrared light, the printed pattern of the visible printing layer 6 is not visible) and recorded on the infrared absorbing layer 4. Since machine-readable information such as a bar code is not visible, the appearance of the information recording medium portion is improved, and there is little suspicion that there is confidential information on the back side where the light diffraction pattern relief layer 3 is attached, and security is reduced. Get better.

When reading mechanically, as described later, information such as a barcode recorded as a hologram image or an image based on a diffraction grating pattern in the light diffraction pattern relief layer 3 with visible light is read, and the infrared light is read. Information such as a barcode recorded as a pattern on the infrared absorption layer 4 is read by light.

The light diffraction pattern relief layer 3 includes
Instead of the machine-readable information, other information on design, authentication, and other purposes for visual recognition may be recorded.

When the light diffraction pattern relief layer 3 is to be peeled off from the base material 7 for forgery or alteration, the transmission of a bar code or the like patterned on the infrared absorption layer 4 by the adhesive force of the adhesive layer 5 is performed. Duplicating the media becomes more difficult as the image is destroyed.

Here, as the light diffraction pattern recorded as the concavo-convex pattern, a relief hologram or a relief diffraction grating in which the intensity distribution of the interference fringes due to the interference between the object light and the reference light is recorded in the concavo-convex pattern. It is recordable, and laser reproduction holograms such as Fresnel holograms, Fraunhofer holograms, lensless Fourier transform holograms, image holograms, and white light reproduction holograms such as rainbow holograms, as well as color holograms and computer holograms utilizing these principles, Hologram display, multiplex hologram,
Examples include holographic stereograms and holographic diffraction gratings that use hologram recording means.In addition, by mechanically creating a diffraction grating using an electron beam lithography device or the like, any diffraction light can be calculated based on calculations. The obtained hologram and diffraction grating can also be mentioned, and these may be recorded singly or in multiples. These holograms or diffraction gratings are generally of a transmission type (the incident side of the illumination light and the observation side of the observer are located on opposite sides of the hologram or diffraction grating), and the surface on which the uneven pattern is formed. By providing the transparent reflection layer 2 on the hologram or the diffraction grating, a reflection type (the incident side of the illumination light and the observation side of the observer are located on the same side with respect to the hologram or diffraction grating) is provided.

Such a light diffraction pattern is obtained by expressing a pattern of a hologram or a diffraction grating once in the form of irregularities using a photosensitive resin, a thermoplastic resin or the like, and forming a relief hologram or a relief diffraction grating. The relief hologram or the relief diffraction grating is molded by plating or the like to prepare and use a mold, so that a large amount of the relief hologram or the relief diffraction grating can be copied by a molding method for a synthetic resin. The resin layer 1 is preferably made of a moldable thermoplastic resin.
As the moldable synthetic resin, a compound such as polyacrylic acid, polyethylene terephthalate, or polypropylene can be used.

In order to provide a relief hologram or a relief diffraction grating on the resin layer 1 using a thermoplastic resin, a conventionally known method can be used. As a mold for forming a relief hologram or a relief diffraction grating,
(1) an interference fringe between an object beam and a reference beam is formed on a photoresist in the form of irregularities by exposure and development;
(2) Any of the molds in which the irregularities of (1) are duplicated can be used, for example, by silver plating or nickel plating on the side (mold surface) having irregularities of (1) above. It is preferred that a large number of relief holograms or relief diffraction gratings be replicated in a single shaping step by duplicating a large number by appropriate means and performing an appropriate arrangement to form a composite type.

The material of the transparent reflection layer 2 is disclosed in
Cr, Ti, Fe, C described in US Pat.
o, Ni, Cu, Ag, Au, Ge, Al, Mg, S
b, Pb, Pd, Cd, Bi, Se, Sn, In, G
It is formed by using a metal such as a and Rb and its oxide, nitride or the like singly or in combination of two or more kinds. As described later, among these, Ge is particularly preferable. The transparent reflection layer 2 is formed by vapor deposition, sputtering, ion plating,
It can be formed by a method such as CVD or plating, and its thickness is preferably 200 to 1000 °. As the material of the transparent reflection layer 2, other materials described in JP-A-6-270884 can also be used.

The hologram or diffraction grating of the present invention basically has the resin layer 1 having the hologram or diffraction grating irregularities on the lower surface and the transparent reflection layer 2 on the lower surface of the resin layer 1 as described above. However, it may be composed of a resin layer 1 having the hologram or diffraction grating unevenness on the upper surface, and a transparent reflection layer 2 provided in contact with the hologram or diffraction grating unevenness.

The infrared absorbing layer 4 which substantially absorbs infrared light and does not absorb visible light includes cyanine dyes, phthalocyanine dyes, naphthoquinone dyes, anthraquinone dyes, zirol dyes, triphenylmethane dyes. A material that is substantially transparent to visible light and absorbs infrared light, such as a material composed of a pigment, a fine powder of ytterbium oxide, copper oxide, or iron oxide and a vehicle, may be used.

Next, when the authentication information for machine reading is recorded in the light diffraction pattern relief layer 3 and the authentication information for machine reading is also recorded in the infrared absorption layer 4, a method for reading both information and its method are described. One example of signal processing is shown in FIG.
As shown in FIG.

As shown in FIG. 2, the light source 11 emits visible light 15 to read information recorded on the light diffraction pattern relief layer 3 and the infrared light 17 emits light to read information recorded on the infrared absorption layer 4. And a visible light sensor 12 that reads a hologram reproduction pattern 21 reproduced by the diffracted light 16 from the light diffraction pattern relief layer 3, Sensor 14 that reads reflected scattered light 18
And place. Both the hologram reproduction pattern 21 recorded on the light diffraction pattern relief layer 3 and the infrared absorption pattern 22 (FIG. 3) recorded on the infrared absorption layer 4 are, for example, numeric bar codes, and the signals of the hologram reproduction pattern 21 are used. Is fixed information, the signal of the infrared absorption pattern 22 is variable information, and the two barcodes are read by the two sensors 1 while moving the information recording medium in the direction of the double arrow in FIG.
2 and 14, and the read signal is input to the arithmetic unit 23 as shown in FIG. 3, where the two signals are added,
Processing is performed by subtraction, multiplication, division, or a combination of these operations, and the result is input to the determination unit 24, and it is determined whether or not the value of the result is within a certain range, for example. Is determined to be forgery or genuine, is output as authentication information, and the read variable information or the result obtained from the arithmetic unit 23 is used. Therefore, if any one of the light diffraction pattern relief layer 3 and the infrared absorption layer 4 is altered or falsified, authentication information can no longer be obtained and advanced authentication can be performed.

As a material of the transparent reflection layer 2, Ge (germanium: refraction) is used without using ZnS (refractive index 1.2) or TiO ₂ (refractive index 2.3) in order to brighten a reproduced image. It is desirable to use the ratio 4.4).
The germanium vapor-deposited layer slightly absorbs visible light and is colored in a light gray color, but transmits a certain amount of visible light and infrared light, so that the back side of the film (light diffraction pattern relief layer 3) can be seen through the vapor-deposited layer. . Therefore, the printed image 6 on the base material 7 on which the hologram or diffraction grating formed on the film is transferred or affixed as a label can be seen without being completely concealed through the vapor deposition layer 2. The refractive index difference between the germanium vapor-deposited reflection layer 2 and the resin layer 1 is 3.0, and a hologram image or a diffraction grating image can be obtained as a clear image by strong refraction and reflection, and the printed image 6 is transmitted. appear. Therefore, when a color copy of the information recording medium is performed, the transmission image 6 is copied. However, since there is no strong diffraction reflection image of the hologram or the diffraction grating, the medium has a completely different texture.

Due to the infrared transmittance of germanium of the reflective layer 2, the bar code or the like of the infrared absorbing layer 4 formed by printing on the medium to be transferred with an ink that absorbs infrared light and transmits visible light is reflected and absorbed by infrared light irradiation. It becomes a pattern and becomes machine readable. Even in the case of the infrared absorbing ink, the dye having a high infrared absorbing efficiency is slightly browned even in visible light, but the germanium vapor deposition reflective layer 2 is also colored in the same color. However, the existence of the infrared absorbing layer 4 cannot be recognized at all.

FIG. 1 shows a case where the information recording medium of the present invention is formed in a card shape. However, as shown in FIG. 4, a transfer support 31 having a release layer 32 formed on one side is used. The light diffraction pattern relief layer 3, the infrared absorbing layer 4, and the adhesive layer 5 are formed on the peelable support 33 through the protective layer 30.
May be sequentially laminated to form a transfer sheet-shaped information recording medium. When the transfer support 31 has releasability, the release layer 32 can be omitted, and if the light diffraction pattern relief layer 3 itself is tough, the protective layer 30 can be omitted. It is also possible to omit the infrared absorbing layer 4 and to provide the infrared absorbing layer 4 on the substrate 7 to which the transfer sheet is transferred. Further, a visible print layer 6 (FIG. 1) may be provided above or below the infrared absorption layer 4.

Further, as shown in FIG.
4 may be provided on the side of the adhesive layer 5 opposite to the light diffraction pattern relief layer 3 to form a seal. In this case, the releasable support 34 is peeled off and adhered on the adherend by the adhesive layer 5 on the peeled side. In the case of FIG. 5,
This is an example in which a base material 7 that reflects at least infrared light is incorporated in a seal.

Incidentally, in the structure as shown in FIGS. 1, 4 and 5, the infrared absorbing layer 4 can be left as a uniform layer of ink in which an infrared absorbing dye is dispersed at first. In this case, recording of a bar code or the like on the infrared absorbing layer 4 can be performed by laser marking on the infrared absorbing layer 4, whether in a card state, in a state of a transfer sheet or label, or in a state of being attached to a medium to be transferred. In this case, the marking can be performed individually by destroying the area other than the necessary area.

Hereinafter, specific examples of the information recording medium according to the present invention will be described. [Specific Example 1] 30 parts of methacrylic resin was dissolved in 70 parts of methyl ethyl ketone as a release layer on a PET film having a thickness of 50 μm and applied to a thickness of 1 μm, and then 30 parts of an acrylic resin was dissolved in 70 parts of methyl ethyl ketone and applied to a thickness of 2 μm. , A micro-embossed copy of the hologram interference pattern copied from the resist by Ni plating,
A germanium-deposited reflective layer having a thickness of 20 nm was formed on the duplicated relief pattern by electron beam deposition. The relief hologram film was coated with an adhesive, and a silicone paper was laminated on the adhesive and punched to produce a label.

This label is attached to a medium obtained by performing offset color printing and infrared absorbing transparent barcode printing on a high quality paper surface with a process ink that does not absorb infrared rays, and absorbing infrared rays through the attached label. When trying to read the transparent barcode visually, infrared absorption printing was impossible to see from above the label, but machine reading using infrared was possible.

[Specific Example 2] A 50 μm-thick PET film was coated as a release layer with 30 parts of methacrylic resin dissolved in 70 parts of methyl ethyl ketone and applied to a thickness of 1 μm, and then 30 parts of acrylic resin was dissolved in 70 parts of methyl ethyl ketone to obtain 2 μm.
Then, a hologram interference pattern copied from a resist by Ni plating was micro-embossed and a germanium-deposited reflective layer having a thickness of 20 nm was formed on the duplicated relief pattern by electron beam evaporation.

On the germanium vapor-deposited reflection layer of this relief hologram film, 3 parts of an infrared absorbing dye CIR-1081 manufactured by Nippon Carlit Co., Ltd. as an infrared absorbing agent and 27 parts of a polyester resin (Toray Co., Ltd. Byron 200) were used. ,
After coating with a gravure ink dispersed in 35 parts of methyl ethyl ketone and 35 parts of toluene, a pressure-sensitive adhesive was applied thereon, and a silicon paper was laminated on the pressure-sensitive adhesive to perform a punching process to produce a label.

This label was subjected to punching and, at the same time, a Q-switched YAG laser was used to laser-mark an individual bar code number on the infrared absorbing dye ink layer of each label. The label after this marking did not change in appearance from before the treatment.

This label is stuck on a medium which has been subjected to offset color printing with a process ink which does not absorb infrared rays on the surface of high-quality paper, and an infrared-absorbing transparent bar code is transmitted through the attached label to a machine using infrared rays. The reading was successful. The bar code could not be seen from the label, but the printed image on the medium could be seen through.

Although this label was forcibly peeled off from the medium, the label coating layer was broken from the vapor deposition reflection layer and remained irregularly on the label, and the printed image was also irregularly taken on the label due to the difference in halftone dot density. The image was destroyed.

[Specific Example 3] As a release layer, 30 parts of methacrylic resin was dissolved in 70 parts of methyl ethyl ketone and applied to a 50 μm thick PET film to a thickness of 1 μm, and then 30 parts of acrylic resin was dissolved in 70 parts of methyl ethyl ketone to obtain 2 μm.
Then, a hologram interference pattern copied from a resist by Ni plating was micro-embossed and a germanium-deposited reflective layer having a thickness of 20 nm was formed on the duplicated relief pattern by electron beam evaporation.

On the germanium vapor-deposited reflection layer of this relief hologram film, 3 parts of an infrared absorbing dye CIR-1081 manufactured by Nippon Carlit Co., Ltd. as an infrared absorbing agent and 27 parts of a polyester resin (Toray Co., Ltd. Byron 200) were used. ,
After coating with a gravure ink dispersed in 35 parts of methyl ethyl ketone and 35 parts of toluene, a heat sealing agent was applied thereon to prepare a transfer foil.

After transferring this transfer foil onto a medium formed by offset color printing with a process ink that does not absorb infrared light on the surface of high-quality paper, the infrared absorption of each transfer portion is determined for each medium using a Q-switch YAG laser. Individual bar code numbers were laser marked on the dye ink layer. No change was observed in the appearance after the marking before the treatment.

When the infrared-absorbing transparent barcode was read mechanically using infrared rays through the transferred transfer foil, it could be read. The bar code could not be seen from the transfer foil, but the printed image on the medium could be seen through.

Although the information recording medium of the present invention and the authentication method thereof have been described based on the embodiments, the present invention is not limited to these embodiments, and various modifications are possible.

[0044]

As is apparent from the above description, according to the information recording medium and the authentication method of the present invention, the hologram or diffraction grating on which the first pattern information is recorded or expressed is recorded as an uneven pattern. Since it is composed of a relief layer, a reflective layer provided at least on the layer which transmits infrared light, and an infrared absorbing layer provided behind the reflective layer and patterned according to the second pattern information, the first layer is formed by visible light. The second pattern can be read with infrared light, the second pattern cannot be visually recognized, and forgery and falsification become difficult by using the two pieces of information. In addition, a visible pattern can be printed for the purpose of blindfolding or design, so that security is further improved, and forgery such as duplication becomes difficult.

In the present invention, variable information such as a serial number is transmitted to the infrared absorbing layer by comparing the information with the hologram or the diffraction grating when compared with the case where information is recognized only by the reflection type hologram or the reflection type diffraction grating to determine the authenticity. Since the media can be added after the formation of the media, the media can be managed by a large number of individual numbers, and if this media number is registered, it is easy to identify the forgery when it occurs.

Further, when Ge is used for the reflective layer in the production of the information recording medium, no extra cost is required for forming the reflective layer as compared with other vapor-deposited substances. Alternatively, in printing, since only one ordinary printing or coating step is added, it is possible to provide a medium at low cost and various countermeasures for preventing forgery.

[Brief description of the drawings]

FIG. 1 is a sectional view of an example of a card-shaped information recording medium according to the present invention.

FIG. 2 is a diagram for explaining a method of reading both information from the information recording medium of FIG. 1;

FIG. 3 is a diagram illustrating an example of signal processing for authentication of an information recording medium using the read signal of FIG. 2;

FIG. 4 is a cross-sectional view of an example when the information recording medium of the present invention is configured in a transfer sheet shape.

FIG. 5 is a cross-sectional view of one example when the information recording medium of the present invention is configured as a seal.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Resin layer 2 ... Transparent reflection layer 3 ... Relief hologram, relief diffraction grating Diffraction grating (light diffraction pattern relief layer) 4 ... Infrared absorption layer 5 ... Adhesive layer 6 ... Visible printing layer 7 ... Base material 11 ... Visible light source 12 visible light sensor 13 infrared light source 14 infrared sensor 15 visible light 16 diffracted light 17 infrared light 18 reflected scattered light 21 hologram reproduction pattern 22 infrared absorption pattern 23 arithmetic unit 24 Judgment part 30 ... Protective layer 31 ... Transfer support 32 ... Release layer 33 ... Releasable support 34 ... Releasable support

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G06K 19/10 G06K 19/00 AR

Claims (8)

[Claims] 1. A relief layer on which a hologram or diffraction grating on which at least first pattern information is recorded or expressed is recorded as a concavo-convex pattern, and at least an infrared-transmissive reflection layer provided on the relief layer; An information recording medium, comprising: an infrared absorbing layer provided behind the reflective layer and patterned according to second pattern information. 2. The information recording medium according to claim 1, wherein a bar code is generated as a diffraction image from the relief layer. 3. The information recording medium according to claim 1, wherein the reflective layer is transparent to visible light. 4. The information recording medium according to claim 3, wherein said reflection layer is made of a germanium vapor-deposited layer. 5. The method according to claim 1, wherein the infrared absorbing layer is patterned by printing.
Information recording medium described in the section. 6. The information recording medium according to claim 1, wherein the infrared absorbing layer is patterned by laser marking after being uniformly applied. 7. A visible printing layer, which is printed using an ink having a characteristic of only absorption and reflection in a visible light region and being reflective in an infrared region, is provided on the reflection layer side or the opposite side of the infrared absorption layer. The information recording medium according to any one of claims 1 to 6, wherein the information recording medium is arranged. 8. A relief layer on which a hologram or diffraction grating on which at least the first pattern information is recorded or expressed is recorded as a concavo-convex pattern, at least an infrared-transmissive reflective layer provided on the relief layer, In an authentication method of an information recording medium comprising an infrared absorbing layer patterned according to second pattern information provided behind the reflective layer, a visible light diffracted light from the relief layer is detected by a visible light detecting device, The first pattern information is read, infrared light is illuminated through the relief layer and the reflective layer, and light that is reflected and emitted through the infrared absorption layer is detected by an infrared light detection device. Reading the second pattern information, performing a predetermined calculation between the two read pattern information, and recording the information based on the calculation result. An authentication method for an information recording medium characterized by identifying the medium.