KR20190044333A - Method of manufacturing laminate - Google Patents

Abstract

According to the present application, a method for manufacturing a laminate can provide a manufacturing method capable of manufacturing a holographic diffractive optical device layer which is included in the laminate and is impossible to be manufactured in the air. The laminate of the present application can be used for recognizing a height pattern of an object being in contact with the laminate.

Description

[0001] The present invention relates to a method of manufacturing a laminate,

The present application relates to a method for producing a laminate.

Recently, security for personal mobile devices such as smart phones and tablet PCs has become a hot topic. As the frequency of users' use of mobile devices increases, security in electronic commerce or the like through mobile devices is required. Biometric information such as fingerprints, irises, facial expressions, voices, and blood vessels are used in response to these demands. The most commonly used technology among various biometric information authentication technologies is fingerprint authentication technology. In recent years, smartphone and tablet PCs have been introduced with fingerprint recognition and authentication technology.

Fingerprint recognition generally includes optical, ultrasonic, capacitive, electric field measurement, and thermal sensing. Dual optics is a generalized authentication means compared to other means with a simple structure and excellent performance.

A conventional optical fingerprint recognition device includes a prism that contacts a light source for irradiating fingerprint recognition light with a finger, a lens for imaging a fingerprint image emitted from the prism, and an image sensor that converts a fingerprint image formed on the lens into an electrical signal . However, such an optical fingerprint recognition device requires a separate sensor and prism for fingerprint recognition, and a large-sized light source is required, thereby increasing the volume of the portable device.

Therefore, an optical fingerprint recognition method that reduces the size of a light source by using light that totally reflects and guides in a region where a fingerprint is to be recognized is being studied.

The present application provides a method for producing a laminate. The laminate of the present application can be used, for example, in an optical fingerprint recognition apparatus.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. The accompanying drawings illustrate exemplary embodiments of the invention and are provided to aid in the understanding of the invention. In the accompanying drawings, the optical paths shown are for the sake of understanding only, so that the refraction generated while passing through the interfaces of the two media can be omitted.

In this specification, the units of angles are degrees (degrees) unless otherwise specified. If the refractive index can be changed by temperature and / or pressure in defining the refractive index of any medium in this specification, the refractive index may be a temperature of 10 ° C to 50 ° C and / or a temperature of 0.90 the refractive index may be a measured refractive index for light having a wavelength of 500 nm to 600 nm at a pressure of atm to 1.10 atm and preferably a refractive index measured for light having a wavelength of 532 nm at 25 ° C and 1 atm.

In the method of manufacturing a laminate of the present application, a first light ray and a second light ray are incident on an interface between a photosensitive material immersed in a refractive index compensation and a refractive index compensation, and a hologram is recorded on the photosensitive material to manufacture a holographic diffraction optical element . ≪ / RTI >

The laminate may include a first base layer, a holographic diffraction optical element layer and a second base layer sequentially laminated. For example, the first base layer 101, the holographic diffraction optical element layer 102, and the second base layer 103 may be sequentially laminated as shown in Fig.

The method of producing a laminate of the present application is a method of producing a laminate used for recognizing a height pattern of an object having a height pattern. In the present specification, the term " object having a height pattern " means an object having a ridge protruding from the surface and a valley embedded in it, and having a predetermined pattern formed by the floor portion and the valley portion . For example, the object having the elevation pattern may be a fingerprint, and the method of manufacturing the laminate of the present application may be a method of manufacturing a laminate for fingerprint recognition. In one example, the laminate may be a laminate for fingerprint recognition that recognizes a fingerprint using total reflection of light.

Referring to FIG. 1, the laminate 100 produced by the method of producing a laminate of the present application is a laminate obtained by using light (106, 107) propagating in a laminate through a predetermined optical path, (104) and the goal (105). Light 106 traveling to the first optical path travels through the interface between the air and the first base layer, between the floor 104 of the fingerprint and the first base layer 101, and between the holographic diffraction optics layer 102 and the second substrate Lt; RTI ID = 0.0 > 103 < / RTI > Herein, the term " light traveling to the first optical path " and " trapped light " refer to the interface between air and the first base layer, the floor 104 of the fingerprint and the first base layer 101, And light traveling to the optical path for total reflection at the interface between the holographic diffraction optical element layer 102 and the second base layer 103. [ The light 107 traveling to the second optical path totally reflects at the interface between the air and the first base layer 101. Since the light traveling to the second optical path is totally reflected as described above, total reflection is also performed in the trough 105 of the fingerprint that comes into contact with the first base layer. The light 107 traveling to the second optical path is transmitted or scattered at the interface between the floor 105 of the fingerprint and the first base layer and is transmitted or scattered at the interface between the holographic diffraction optical element layer 102 and the second base layer 103 At the interface, it permeates. In the present specification, the term " light traveling to the second optical path " and " selectively total reflection light " are totally reflected at the interface between air and the first base layer 101 in the laminate, May be transmitted or scattered at the interface between the holographic diffraction optical element layer 102 and the first base layer 103 and light traveling through the optical path passing through the interface between the holographic diffraction optic element layer 102 and the second base layer 103.

The first base layer 101, the holographic diffraction optical element layer, and the second base layer 103 may satisfy the following general formulas 2 to 4 so as to enable total reflection as described above.

[Formula 2]

n ₁ > n _air

[Formula 3]

n _hoe > n ₂

[Formula 4]

n ₁ > n _o

In the general formula 2 to 4, n ₁ is the refractive index of the layer a first substrate, a refractive index of n _air air, n _hoe is the refractive index of the graphics-optic medium layer alone, n ₂ is a refractive index of the second substrate layer, n _o Is a refractive index of a portion of an object having a height pattern directly contacting the first base layer. The portion of the object having the height pattern directly contacting the first base layer may be a floor portion of the object, for example, a floor portion of the fingerprint in contact with the first base layer.

As shown in Fig. 1, the light 106 traveling to the first optical path is trapped inside the laminate produced by the method of manufacturing the laminate of the present application. The light 106 traveling to the first optical path is trapped in the region inside the laminate regardless of whether or not an object having a height pattern, for example, a fingerprint, is in contact with the first base layer, The light 106 can function as a light source for generating light 107 that travels from the entire area inside the laminate to the second optical path. Accordingly, the laminate is a light source (not shown) ) Can be reduced.

As shown in Fig. 1, the light 106 traveling to the first optical path is trapped inside the laminate manufactured by the method of manufacturing the laminate of the present application. The fact that the light is trapped inside the laminate means that the light does not flow out to the outside by repeating the total internal reflection inside the laminate. More specifically, as described above, the light 106 traveling to the first optical path is incident on the interface between the air and the first base layer, the interface between the base 104 of the fingerprint and the first base layer 101, The light 107 is totally reflected at the interface between the element layer 102 and the second base layer 103 and the light 107 traveling to the second optical path is totally reflected at the interface between the air and the first base layer 101. [

The light 106 traveling to the first optical path may be generated by a light source separately provided in, for example, a fingerprint recognition device including a laminate. In one example, a light source (not shown) is disposed on one edge side of the laminate so that the light emitted from the light source is incident on the interface between the first base layer and the air at the angle A shown in Fig. 1, Progressive light 106 can be generated. The light source is not limited as long as it emits light suitable for optical fingerprint recognition. For example, a laser diode or a light emitting diode can be used.

The holographic diffraction optical element layer is formed by, for example, forming a part of light traveling to the first optical path incident on the interface between the air and the first base layer at an angle A to the second optical path Lt; / RTI > The diffraction may be performed by a hologram recorded in the holographic diffraction optical element layer. As shown in Fig. 1, the light 106 traveling to the first optical path travels to the optical path incident on the interface between the air and the first base layer 101 at an angle A, and the light traveling to the second optical path (107) is light traveling to an optical path incident at an angle B to the interface between air and the first base layer (101).

In one example, the first optical path is totally reflected at the interface of the air and the first base layer, and is not totally reflected at the interface of the first base layer and the holographic diffraction optical element layer, and the holographic diffraction optical element layer and the second substrate Lt; RTI ID = 0.0 > interface. ≪ / RTI > In the above example, the light traveling to the first optical path can be trapped inside the laminate, and is incident on the holographic diffraction optical element layer in the course of repeating total reflection.

In order for the first optical path to travel as described above, the angle A at which light traveling to the first optical path enters the interface between air and the first base layer must satisfy the following formulas 5 to 7.

[Formula 5]

A> sin ^-1 (n _o / n ₁ ) × 180 ° / π

[Formula 6]

A <sin ^-1 (n _hoe / n ₁ ) × 180 ° / π

[Formula 7]

A> sin ^-1 (n ₂ / n ₁ ) × 180 ° / π

In the general formulas 5 to 7, n ₁ is the refractive index of the first base layer, n ₂ is the refractive index of the second base layer, n _hoe is the refractive index of the holographic diffractive optical element layer, and n _o is the refractive index The refractive index of the portion of the object directly contacting the first base layer, for example, the refractive index of the floor of the fingerprint.

In one example, the second optical path is totally reflected at the interface between the air and the first base layer, and is a portion of the object having a height pattern directly contacting the first base layer, for example, And may not be totally reflected at the interface between the first base layer and the holographic diffraction optical element layer and may not be totally reflected at the interface between the holographic diffraction optical element layer and the second base layer. In the above example, the light traveling to the second optical path selectively totally reflects the height pattern pattern of the fingerprint in contact with the upper surface portion of the first base layer, so that the information of the height pattern of the fingerprint in contact with the first base layer, So that it can be transmitted to the outside. For example, an image of a height pattern of a fingerprint in contact with the first base layer can be formed through a photosensor array disposed under the second base layer.

In order for the second optical path to travel as described above, the angle B at which the light traveling to the second optical path enters the interface of the air and the second base layer should satisfy the following formulas 8 to 10.

[Formula 8]

sin ^-1 (n _air / n ₁ ) × 180 ° / π <B <sin ^-1 (n _o / n ₁ ) × 180 ° /

[Formula 9]

B <sin ^-1 (n _hoe / n ₁ ) × 180 ° / π

[Formula 10]

B <sin ^-1 (n ₂ / n ₁ ) × 180 ° / π

In the general formulas 8 to 10, n ₁ is the refractive index of the first base layer, n ₂ is the refractive index of the second base layer, n _hoe is the refractive index of the holographic diffraction optical element layer, n _air is the refractive index of air , and n _o is the refractive index of a portion of the object having the height pattern directly contacting the first base layer, for example, the floor portion of the fingerprint.

The light 107 traveling to the second optical path, which conveys the information of the height pattern of the object in contact with the first base layer, is a part of the light 106 traveling through the first optical path of the holographic diffraction optical element layer 107 . &Lt; / RTI &gt; That is, the light 106 traveling to the first optical path functions as a light source of the light 107 traveling to the second optical path. The light 106 traveling to the first optical path serving as the light source of the light 107 traveling to the second optical path travels trapped inside the stacked body and proceeds so that the light 107 traveling to the second optical path travels inside the stacked body Can be generated by the holographic diffraction optical element layer in the entire region. Therefore, the laminate produced by the method of producing a laminate of the present application can reduce the size of the light source by using the holographic diffraction optical element layer, and unlike an optical type fingerprint recognition device capable of fingerprint recognition only at the upper portion of the light source, Fingerprint recognition is possible.

The kinds of the first base layer and the second base layer of the laminate are not particularly limited as long as they satisfy the above-described general formulas 2 to 4, and preferably optically transparent ones satisfying the above-mentioned general formulas 2 to 4 are used . In one example, the first substrate layer can be composed of a material that can be used as a cover glass of a display device, and the second substrate layer can be an optical adhesive used in the display field.

The manufacturing method of the laminate of the present application may include a step of manufacturing a holographic diffraction optical element. A transmissive or reflective hologram may be recorded in the holographic diffraction optical element.

FIG. 2 shows a general transmission type hologram recording method 200. FIG. 2, the first light 202 and the second light 203 are irradiated on one surface of the photosensitive material 201 to expose the photosensitive material, and as a result, the photosensitive material 201 is irradiated with the first light 202 and the second light 203, An interference pattern 204 is formed. In the present specification, the term &quot; exposure &quot; may refer to a process in which two light beams having different optical paths propagate in the photosensitive material, and an interference pattern is formed in the photosensitive material due to interference of the two light beams.

The recording of the reflection type hologram uses the first light and the second light similarly to the transmission type hologram, but the first light and the second light are not irradiated on one surface of the photosensitive material, but are incident on one surface and the opposite surface So that an interference pattern is formed.

The type of the photosensitive material used in the method for producing a laminate of the present application is not particularly limited as long as it can form an interference pattern due to the interference of irradiated light rays. In the field of hologram recording, various photosensitive materials capable of recording holograms are known. In this application, a suitable photosensitive material can be selected and used in consideration of the photosensitive performance of the photosensitive material. In one example, the photosensitive material may be a photosensitive material layer formed on a glass or triacetylcellulose (TAC) substrate.

The kind of the first and second light beams used in the method of manufacturing the laminate of the present application is not particularly limited as long as it can form an interference pattern on the selected photosensitive material. For example, a laser can be used. Preferably, continuous wave lasers (CW lasers) can be used as the first and second light beams. A continuous wave laser may mean a laser capable of oscillating a continuous beam with a constant output in time. Also, longitudinal mode lasers can be used as the first and second light beams. The longitudinal mode laser is a laser having a vibration parallel to the resonator axis, and may mean a laser having the same vibration direction and traveling direction. More preferably, the first light beam and the second light beam may be a single longitudinal mode laser. Single mode can mean that the resonator of the laser selects and amplifies only one band.

The laminate produced by the laminate production method of the present application uses light traveling to the above-described first and second optical paths. As described above, the light traveling to the second optical path can be formed by diffracting a part of the light traveling to the first optical path trapped in the laminate, by the holographic diffraction optical element layer.

What can function as a holographic diffractive optical element layer that forms light selectively reflecting from the trapped light as described above can be, for example, a holographic diffractive optical element.

The manufacturing method of the laminate of the present application may include, for example, a step of manufacturing the holographic diffraction optical element. The step of fabricating the holographic diffractive optical element may include irradiating the first light beam and the second light beam to the interface between the photosensitive material immersed in the refractive index compensation and the refractive index compensation to record the hologram in the photosensitive material. The fact that the photosensitive material is immersed in the refractive index compensation means that all or a part of the photosensitive material is contained in the refractive index compensation.

In the present specification, &quot; incident first light ray and second light ray at the interface between the photosensitive material and the refractive index compensation &quot; means that at least one of the first light ray and the second light ray passes through the refractive index compensation, It may mean that the second light beam irradiates the first light beam and the second light beam such that the second light beam is irradiated at either interface where the refractive index adjustment and the photosensitive material are in contact with each other.

In order to manufacture the holographic diffraction optical element, for example, as shown in FIG. 2, the first light 202 and the second light 203 should travel in a predetermined optical path within the photosensitive material 201 do. Particularly, in order to manufacture a holographic diffractive optical element that forms light selectively and totally reflected from the trapped light as described above, it is preferable that the angle at which the trapped light travels in the holographic diffractive optical element layer, A light beam incident on the photosensitive material so that the light rays incident on the photosensitive material progress inside the photosensitive material and the light propagating in the photosensitive material progresses at an angle corresponding to the angle at which the selectively reflected light advances in the holographic optical element layer do.

For example, when the interference pattern 204 is to be recorded on the photosensitive material 201 in a manner similar to that described in Fig. 2, the first light 202 and the second light 203 are respectively incident on the photosensitive material 201, In the exemplary stack shown in FIG. 1, the angle at which the trapped light 106 travels in the holographic diffractive optical element layer 102 and optionally the total reflected light 107 travels through the holographic diffractive optical element layer The first light 202 and the second light 203 must be irradiated to the photosensitive material 201 so as to proceed at an angle corresponding to an angle that advances within the photosensitive material 201. [

However, even if the photosensitive material is irradiated with light at any angle in the air, at least one of the first light 202 and the second light 203 is diffracted at the above-mentioned angle in the photosensitive material due to the difference in refractive index between air and the photosensitive material I can not proceed. In order to solve the above problem caused by the refractive index difference between the air and the photosensitive material, the method of manufacturing the laminate of the present application uses a refractive index compensation.

Fig. 3 is a diagram showing the steps of manufacturing the exemplary holographic diffractive optical element of the present application. Fig. As shown in FIG. 3, a method of manufacturing an exemplary laminated body includes a step of irradiating a first light ray 303 and a second light ray 304 to an interface at which the photosensitive material 301 and the refractive index adjuster 302 are in contact with each other .

In one example, as shown in FIG. 4, the refractive index adjustment unit 401 includes fixing means 402 for fixing the photosensitive material and incident angle adjusting means 403 for adjusting the angle of light irradiated to the photosensitive material And the photosensitive material can be stably immersed in the refractive index adjustment by fixing the photosensitive material to the fixing means provided in the container.

At least one of the first light ray and the second light ray may satisfy the following general formula (1).

[Formula 1]

θ _pp > sin ^-1 (n _air / n _pp ) × 180 ° / π

In the above general formula (1),? _Pp is the angle at which the light beam travels in the photosensitive material on the incident plane, n _air is the refractive index of air at 25 ° C and 1 atmosphere, and n _pp is the refractive index of the photosensitive material. As shown in Fig. 3, at least one of the first light beam and the second light beam may satisfy Formula 1 in the photosensitive material 301 in order to manufacture the holographic diffractive optical element described above. The fact that at least one of the first light ray and the second light ray satisfy Formula 1 means that when at least one of the first light ray and the second light ray is incident at the interface between air and the photosensitive material inside the photosensitive material, The optical path of the laser beam can not proceed due to the refractive index of the laser beam.

The refractive index of the refractive index compensation can be selected within a range that can solve the above-described problems, and for example, the following general formulas 7 and 8 can be satisfied.

[Formula 7]

n _l > _pp × sinA

[Formula 8]

n _l > _pp × sinB

In the above general formulas 7 and 8, n ₁ is the refractive index of the refractive index compensation, n _pp is the refractive index of the photosensitive material, and A and B are the angles defined in the above-described general formulas 5 and 6, respectively. By using a refractive index compensation having a refractive index satisfying the above general formulas 7 and 8, it is possible to record a hologram even if any one of the first and second light beams satisfies the condition of the general formula 1 described above, A part of the diffracted light is diffracted so as to proceed to the second optical path.

The kind of the refractive index is not particularly limited as long as it satisfies the above-mentioned refractive index and can record a hologram which can not be recorded in the air. For example, water, silicone oil, alcohol, .

The manufacturing method of the laminate of the present application may further include the step of replicating the holographic diffractive optical element on which the hologram is recorded by the manufacturing method of the present application, to the photosensitive material for duplication. FIG. 5 is a diagram showing a reproduction step of an exemplary transmission type holographic diffraction optical element. FIG. 5, the copying step 500 of the method of manufacturing a laminate according to the present application is a method in which the holographic diffraction optical element 501 and the copying photosensitive material 502 are sequentially laminated, ) And copying the hologram recorded in the holographic diffraction optical element 501 to the photographic material 502 for copying. Although the holographic diffractive optical element 501 and the photographic photosensitive material 502 for copying are spaced apart from each other, the holographic diffractive optical element 501 and the photographic photosensitive material for copying 502 may be in contact with each other. Unlike the exemplary replication step of FIG. 5 using a transmissive holographic diffractive optical element, it will be understood by those skilled in the art that the direction of the diffracted light irradiated to the stack must be different when using a reflective holographic diffractive optical element. 5, when the duplicated light 503 is irradiated onto the laminate of the holographic diffraction optical element 501 and the photographic material 502 for copying, the holographic diffraction optical element 501 is irradiated with the duplicated light 503 503 are diffracted to form diffracted diffracted light 504. The photosensitive material 502 for copying is exposed by the duplicated light 503 transmitted through the holographic diffraction optical element 501 and the diffracted duplicated light 504 so that an interference pattern is formed on the photosensitive material 502 for duplication .

The term &quot; duplicating &quot; the hologram recorded in the holographic diffractive optical element in this specification means, for example, that the holographic diffractive optical element diffracts a part of the light incident at the X- The hologram is recorded in the photosensitive material for copying by irradiating the layered product of the holographic diffraction optical element and the photographic material for copying with a copying light so that the photographic material for copying is also irradiated with X angle May be a holographic diffraction optical element which diffracts a part of the light incident on the incident plane at a Y angle. The &quot; copying &quot; is not limited to the case where the holographic diffraction optical element and the copying photosensitive material have the same diffraction efficiency defined by the ratio of the intensity of the diffracted light to the total intensity of the diffracted light and the diffracted light, But also different cases may be included.

In the present specification, the holographic diffractive optical element used for duplication may be referred to as a &quot; master &quot;, and the holographic diffractive optical element duplicated by the holographic diffractive optical element may be referred to as &quot; copy &quot;.

When copying is made by duplicating the master as described above, mass production of the laminate produced by the production method of the laminate of the present application can be facilitated. The mass production is, for example, carried out by a roll-to-roll process in which a photosensitive material for copying for making a copy is conveyed by a roll, and the photosensitive material for copying and the master are stacked and the light is irradiated in a scanning manner .

The manufacturing method of the laminate of the present application can provide a manufacturing method capable of manufacturing a holographic diffraction optical element layer included in the laminate which is impossible to manufacture in air.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram schematically showing an exemplary laminate of the present application. Fig.
2 is a diagram showing an exemplary transmission type hologram recording method.
3 is a diagram illustrating a step of manufacturing an exemplary holographic diffractive optical element of the present application.
Figure 4 shows an exemplary container of the present application.
5 is a diagram illustrating an exemplary replication step of the present application.
6 shows the result of measurement of the diffraction angle according to the incident angle of the holographic diffraction optical element manufactured in the embodiment.

Hereinafter, the method for producing the laminate of the present application will be described with reference to Examples, but the method for producing the laminate of the present application is not limited to the above Examples.

Examples. Manufacture of holographic diffractive optical element using refractive index compensation

The photosensitive material 301 is immersed in the refractive index adjuster 302 as shown in Fig. The photosensitive material has a refractive index of 1.5. A polyol was used as a refractive index compensator, and the refractive index of the polyol was 1.45 at 25 ° C.

A first light ray and a second light ray were irradiated to the photosensitive material immersed in the polyol, and the photosensitive material was exposed by the first light ray and the second light ray. A single mode laser with a wavelength of 532 nm was used as the first and second light beams. Inside the polyol, the first ray was incident at the interface between the polyol and the photosensitive material at 47 degrees, and the second ray was incident at the interface between the polyol and the photosensitive material at 80 degrees. The first light beam travels at an angle of 45 [deg.] On the incident plane in the photosensitive material, and the second light ray travels at an angle of 72 [deg.] On the incident plane in the photosensitive material. Therefore, when referring to the general formula 1, since n _air is 1 and n _pp is 1.5, since the right side of the general formula 1 becomes about 41.8 °, it can be seen that the first and second rays satisfy the above-mentioned general formula 1 .

The result of measuring the diffraction angle according to the incident angle of the manufactured holographic diffraction optical element is shown in FIG. As a result of the measurement, it was found that the angle of incidence at 72 ° was diffracted at 45 °.

Comparative Example. Manufacture of holographic diffractive optical element

The first and second light beams are incident on the interface of the air and the photosensitive material so that the first light ray advances at an angle of 72 ° in the photosensitive material without using the refractive index compensation and the second light ray can travel at an angle of 45 ° in the photosensitive material. I tried to investigate the ray. However, since the critical angle of total reflection between the air (n _air = 1) and the photosensitive material (n _pp = 1.5) is 41.8 °, even if the light is irradiated at any angle in the air, So that it was impossible to manufacture a diffractive optical element that diffracts a light ray incident at an angle of 72 degrees at 45 degrees.

100:
101: a first substrate layer
102: holographic diffraction optical element layer
103: a second substrate layer
104: The floor of the fingerprint
105: Fingerprints
106: Light traveling to the first optical path
107: Light traveling to the second optical path
200: transmission type hologram recording method
201: Photosensitive material
202: First light
203: second light
204: interference pattern
300: Holographic diffraction optical element manufacturing step
301: Photosensitive material
302: Refractive index correction
303: 1st ray
304: 2nd ray
400: container
401: Refractive index correction
402: Fixing means
403: Incident angle adjusting means
500: Replication step
501: holographic diffraction optical element
502: Photosensitive material for reproduction
503: Replication light
504: diffracted diffracted light

Claims (6)

A method for manufacturing a laminate including a first base layer, a holographic diffraction optical element layer and a second base layer sequentially laminated,
And forming a holographic diffraction optical element by irradiating a first light beam and a second light beam at an interface between the photosensitive material immersed in the refractive index compensation and the refractive index compensation to record a hologram in the photosensitive material. The method for producing a laminate according to claim 1, wherein at least one of the first light ray and the second light ray satisfies the following general formula (1)
[Formula 1]
θ _pp > sin ^-1 (n _air / n _pp ) × 180 ° / π
In the general formula (1),? _Pp is the angle at which the light beam travels in the photosensitive material on the incident plane, n _air is the refractive index of air, and n _pp is the refractive index of the photosensitive material. The method for producing a laminate according to claim 1, wherein the laminate satisfies the following formulas 2 to 4:
[Formula 2]
n ₁ > n _air
[Formula 3]
n _hoe > n ₂
[Formula 4]
n ₁ > n _o
In the general formula 2 to 4, n ₁ is the refractive index of the first base material and the refractive index of the layer, n _air is 25 ° C and 1 atmosphere, in which the refractive index of air, n _hoe is a holographic optical element in a layer, n ₂ is the 2 is the refractive index of the base layer, and n _o is the refractive index of the portion of the object having the height pattern directly contacting the first base layer. 2. A holographic diffractive optical element according to claim 1, wherein the holographic diffractive optical element layer comprises a first portion of light incident on the interface between the air and the first base layer at an angle A, Diffracted to proceed to the optical path,
The first optical path is totally reflected at the interface between the air and the first base layer and is totally reflected at the interface between the first base layer and the holographic diffraction optical element layer, Lt; / RTI >
The second optical path is totally reflected at the interface between the air and the first base layer and is totally reflected from the portion of the object having the height pattern directly contacting the first base layer and the interface of the first base layer, The optical path is not totally reflected at the interface of the graphic diffraction optical element layer and is not totally reflected at the interface between the holographic diffraction optical element layer and the second base layer,
Wherein the angle A satisfies the following general formulas 5 to 7 and the angle B satisfies the following general formulas 8 to 10:
[Formula 5]
A> sin ^-1 (n _o / n ₁ ) × 180 ° / π
[Formula 6]
A <sin ^-1 (n _hoe / n ₁ ) × 180 ° / π
[Formula 7]
A> sin ^-1 (n ₂ / n ₁ ) × 180 ° / π
[Formula 8]
sin ^-1 (n _air / n ₁ ) × 180 ° / π <B <sin ^-1 (n _o / n ₁ ) × 180 ° /
[Formula 9]
B <sin ^-1 (n _hoe / n ₁ ) × 180 ° / π
[Formula 10]
B <sin ^-1 (n ₂ / n ₁ ) × 180 ° / π
In the general formulas 5 to 10, n ₁ is the refractive index of the first base layer, n ₂ is the refractive index of the second base layer, n _hoe is the refractive index of the holographic diffractive optical element layer, n _air is the refractive index of air , and n _o is a refractive index of a portion of the object having a height pattern directly contacting the first base layer. The method for producing a laminate according to claim 4, wherein the refractive index of the refractive index compensation satisfies the following formulas 11 and 12:
[Formula 11]
n _l > _pp × sinA
[Formula 12]
n _l > _pp × sinB
In the above general formulas 11 and 12, n ₁ is the refractive index of the refractive index compensation and n _pp is the refractive index of the photosensitive material. The method according to claim 1, further comprising the step of irradiating the layered product in which the holographic diffraction optical element and the photographic material for copying are sequentially laminated to reproduce the hologram recorded in the holographic diffraction optical element, By weight.

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