JP2008026845A - Three-dimensional image display screen system and three-dimensional image display device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional image display screen system which is excellent in transparency and diffraction efficiency, has uniform brightness as the whole screen and can be easily prepared with respect to the three-dimensional image display screen system for applying a reconstruction method of parallax rays, and to provide a three-dimensional image display device using the three-dimensional image display screen system. <P>SOLUTION: The three-dimensional image display screen system 1 can visualize a three-dimensional image by causing transmission light of respective projected light rays to converge or diverge when a plurality of light rays constituting a two-dimensional image are projected from a projector 9. The three-dimensional image display screen system includes a hologram screen (or diffusion screen) 12 and a plurality of volume phase type hologram lenses 11 which diffract irradiated light rays into specified directions, respectively. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a three-dimensional image display screen system for displaying a three-dimensional image on a hologram screen or the like, and a three-dimensional image display apparatus using the same.

Conventionally, there has been proposed a hologram display device using a hologram screen that uses a hologram element as a screen and diffracts a real image formed using a projector to an observer on the opposite side of the projector (Patent Literature). 1-2).
In a hologram display device using such a hologram screen, the reproduced image can be observed while seeing through the background.
By using such a hologram screen, for example, it is possible to perform customer service while checking customers and patients at a window such as a bank or a hospital. In this case, the video can be displayed on the customer side (displays video for the customer) or can be displayed on the customer service side (displays the video for the store clerk who serves the customer). Furthermore, by using the hologram screen, advertisement images and the like can be displayed on the window glass of various showrooms such as department stores and underground malls. In this case, an image can be presented without obstructing the observation of exhibits in the showroom. Moreover, such a holographic screen can also be used as a head-up display for various moving bodies such as automobiles.

  In recent years, as a technique for stereoscopically viewing a still image, a stereoscopic vision technique using a lenticular lens plate or an eyelet lens plate is known (see Non-Patent Document 1). A lenticular lens is an optical element in which fine cylindrical lenses are arranged on the surface. The eyelet lens plate is an integrated optical element in which a large number of small convex spherical lenses having a diameter of several mm are arranged on a plane.

  On the other hand, in recent years, a three-dimensional image display method called a parallax light reproduction method has been proposed (see Non-Patent Documents 2 to 4). Such parallax ray reproduction method is a method of reproducing a three-dimensional image by reproducing the point light source based on the idea that a generally displayed three-dimensional image is composed of a collection of point light sources. Hereinafter, the parallax light beam reproduction method will be described more specifically with reference to FIG.

FIG. 1 is an explanatory diagram for explaining the concept of a three-dimensional image display method based on a parallax light reproduction method. As shown in FIG. 1, the parallax light beam reproduction method diffracts each irradiated light beam in a specific direction (in the example shown in FIG. 1, the directions of the light beams A1 and B3 according to the hologram part irradiated with the light beam). A plurality of holograms 11 'are recorded (three holograms shown in FIG. 1 represent one hologram). The holograms 11' are illustrated as being diffracted in the three directions of light rays A2 and B2 and light rays A3 and B1. Actually, even in the same hologram, the diffraction direction is continuously different depending on the portion irradiated with the light beam, but in FIG. The diffraction direction is constant and the diffraction direction is different at different squares, and a small number of holograms are shown in FIG.
The screen 1 'on which about 0000 holograms are recorded) is irradiated with parallel light from the light source 2, and part of the hologram 11' is shielded by the mask M to reproduce the point light source. is there. That is, in the example shown in FIG. 1, the virtual image point light source A is reproduced by the three divergent rays A1, A2, and A3 that are transmitted through the screen 1 'without being shielded and diffracted, while the three convergent rays B1, A real image point light source B is reproduced by B2 and B3. The parallax light reproduction method is a method of reproducing a plurality of point light sources by appropriately setting the arrangement of the mask M, thereby reproducing a three-dimensional image.

In addition, as an actual apparatus configuration for carrying out such a parallax light beam reproduction method, a digital micromirror device (DMD) is used as the mask M, and the reflected light amount of the light beam emitted from the light source 2 is determined for each element of the device. A configuration that realizes the function of the mask M by independently controlling each time or using a liquid crystal display (LCD) as the light source 2 and the mask M and independently controlling the density of each pixel of the display. Has been. Further, the plurality of holograms 11 ′ that diffract the irradiated light beams in specific directions interfere with two light beams of the reference light and the object light for each predetermined region of the silver salt photosensitive material applied on the surface of the screen 1 ′. Recorded by exposure.
JP-A-9-114354 JP 2000-155374 A Hiroshi Inoue, “Searching for the mystery of stereoscopic vision”, Optronics Publishing H.TAKAHASHI, K.SAKAMOTO, H.UEDA, E.SHIMIZU, “3-D DISPLAY SYSTEM WITH A HOLOGRAPHIC OPTICAL ELEMENT”, PRPC. OF IDW, 1996, p.473-476 R.KISHIGAMI, H.TAKAHASHI, E.SHIMIZU, “REAL-TIME COLOR THREE-DIMENSIONAL DISPLAY SYSTEM USING HOLOGRAPHIC OPTICAL ELEMENTS”, PRPC. OF SPIE, 2001, p.102-107 H.TAKAHASHI, K.YAMADA, E.SHIMIZU, “ARBITRARY VIEWPOINT 3D DISPLAY SYSTEM”, PRPC. OF SPIE, 2003, p.50-58

  However, when a screen formed using an existing silver salt photosensitive material is used as a screen for performing the above-described parallax ray reproduction method, the diffraction efficiency is 10% or less, and a bright image can be obtained. There was a problem that I could not.

  In addition, the conventional method of combining a diffusing plate, a lenticular lens plate, and an eyelet lens plate is capable of stereoscopic viewing, but has a problem that it cannot express a stereoscopic effect that is very low in transparency and floating in space. there were.

  The present invention has been made to solve such problems of the prior art, and is a three-dimensional image display screen system for stereoscopic viewing using a projector, which is excellent in transparency and diffraction efficiency. It is an object of the present invention to provide a three-dimensional image display screen system that has uniform brightness as a whole and that can be easily manufactured, and a three-dimensional image display device using the same.

  In order to solve the above problems, the inventors of the present invention have intensively studied, and as a result, conceived that the above problems can be solved by combining a hologram screen and a hologram lens using a specific photopolymer photosensitive material. It has been completed.

  That is, the screen system for displaying a three-dimensional image of the present invention is configured to converge or diverge the transmitted light of each projected light when a plurality of light beams constituting a two-dimensional image are projected from the projector. A screen system for displaying a three-dimensional image capable of visually recognizing a two-dimensional image, wherein light beams irradiated by exposing two photo fluxes of reference light and object light to the entire surface of the photopolymer photosensitive material are specified. A volume phase hologram screen that diffracts in a direction and a plurality of volumes that diffract light beams irradiated in a specific direction by exposing two beams of reference light and object light to interfere with each other in a predetermined region of the photopolymer photosensitive material. It is characterized by being combined with a hologram lens provided with a phase hologram.

  According to such an invention, since a photopolymer photosensitive material is used as a photosensitive material for recording a hologram, it is possible to obtain a screen system that does not include particulate components and is excellent in transparency and diffraction efficiency. In addition, it is possible to record holograms without the need for wet development processing, and since the film (hologram) shrinkage due to polymerization shrinkage of the polymer contained in the photopolymer is also constant, Compared to the case of recording a hologram using a silver salt photosensitive material, the film thickness distribution of the hologram becomes uniform, and as a result, the entire screen system has a uniform brightness. Furthermore, since it is possible to record a hologram without requiring wet development processing, the photopolymer photosensitive material is coated when recording the hologram on the photopolymer photosensitive material (when performing two-beam interference exposure). If the light-shielding mask is brought into contact with the protective substrate, the surface of the photopolymer photosensitive material is not damaged, and it is not necessary to peel off the protective substrate even after exposure. Easy.

  By using the screen system of the present invention, it is possible to realize a very transparent screen system, and it is possible to display a three-dimensional image in a transparent state.

  The screen system for displaying a three-dimensional image according to the present invention exposes the irradiated light beams in a specific direction by exposing the two light beams of the reference light and the object light for each predetermined region of the photosensitive material coated on the surface. A screen system for displaying a three-dimensional image provided with a plurality of volume phase hologram lenses for diffracting the image, and the image light of the parallax image projected from the projection device is scattered and diffracted by the hologram screen or the diffusion screen. It is also preferable to make the three-dimensional image visible by forming an image of the transmitted light of each projected light beam with the hologram lens.

Since the hologram lens is composed of a plurality of volume phase hologram lenses, unlike the conventional lenticular lens plate and eyelet lens plate, the surface has no irregularities. Therefore, when observing a three-dimensional image, there is no inconvenience that the eye has a focal point on the uneven surface. By setting the diffraction angle, it is possible to form an image at a position where the optical axis from the light source is removed, and the observer does not feel glare.
According to this screen system, for example, as shown in FIG. 10, the image light from the projection device (point light source) is scattered and diffracted by the diffusing screen 12, so that the incident light on the hologram lens 11 is close to parallel rays. Can be converted. As a result, light rays are incident on the hologram lens 11 almost uniformly, and the focusing accuracy is improved as compared with the case where only the hologram lens 11 is used, and a three-dimensional image with a more stereoscopic effect can be formed. For example, in FIG. 10, the light beam that has passed through the hologram lens 11 converges and forms an image as indicated by a solid line, and the image that converges and forms an image as indicated by a chain line appears to overlap with an appropriate deviation. This is because the human eye recognizes it as a solid.

In particular, the screen is preferably a volume phase hologram screen or an embossed hologram screen.
With such a screen, the diffraction angle of transmitted light can be freely changed by design, so that a three-dimensional image can be observed at a position deviated from the optical axis from the projection device (point light source). In addition to the advantage that the observer does not feel glare, there is also the advantage that the installation location of the screen system can be freely selected. Further, since the transmitted light can be diffracted at a certain angle, each light beam can be uniformly incident on the hologram lens at the calculated angle, and the focus accuracy is further improved.

Alternatively, it is more preferable that the screen has a photopolymer as a main component, the transmittance of the screen with respect to 0 ° incident light is 65% or more, and the transmittance with respect to incident light at a set diffraction angle is 40% or more.
Hologram screens or diffusion screens mainly composed of photopolymers are superior in transparency and diffraction efficiency compared to screens using conventional silver salt photosensitive materials. A three-dimensional image display screen system including a screen having such transmittance can form a brighter and three-dimensional image.

In the screen system for displaying a three-dimensional image according to the present invention, the hologram lens has a photopolymer as a main component, and a radical polymerizable monomer and a binder polymer are mixed as a composition of the photopolymer to form a refractive index distribution. It's also good.
Since the hologram lens having such characteristics has high transparency and high diffraction efficiency, it is possible to form an image with better brightness and stereoscopic effect.

  The present invention further includes: the screen system for displaying a three-dimensional image; and a projector that projects a light beam that forms a two-dimensional image onto the screen system for displaying a three-dimensional image. The present invention is also provided as a three-dimensional image display device characterized in that the amount of light incident on the three-dimensional image display screen of each light beam constituting the three-dimensional image can be independently controlled.

  According to this three-dimensional image display device, since the three-dimensional image can be observed at a position deviated from the optical axis of the light beam from the projector, the observer does not feel glare. Since the three-dimensional image formed by the above-described three-dimensional image display screen system has high transparency and high diffraction efficiency, an observer can visually recognize the image as if it is transparent.

  According to the present invention, a screen system for displaying a three-dimensional image having excellent transparency and diffraction efficiency, uniform brightness as a whole screen system, and easy to manufacture, and a three-dimensional image display device using the same are obtained. be able to.

  Hereinafter, an embodiment of a screen system for displaying a three-dimensional image according to the present invention will be described with reference to the accompanying drawings as appropriate.

  FIG. 2 is a front view showing a schematic configuration of a three-dimensional image display screen according to an embodiment of the present invention. As shown in FIG. 2, the 3D image display screen system (hereinafter referred to as “screen system” as appropriate) 1 according to the present embodiment is used when a plurality of light beams constituting a 2D image are projected from a projector. The three-dimensional image can be viewed by converging or diverging the transmitted light of each projected light beam, and the reference light and object light are applied to the entire surface of the photopolymer photosensitive material applied on the surface. The volume phase hologram screen (hereinafter referred to as “hologram screen” as appropriate) 10 that diffracts the irradiated light beam in a specific direction is recorded without the need for wet development processing by interfering with the two light beams. Is provided. In addition, each light beam recorded and irradiated without the need for wet development processing can be identified by exposing the reference beam and object beam to interfere with each other in a predetermined area of the photopolymer photosensitive material applied on the surface. A plurality of volume phase hologram lenses (hereinafter referred to as “hologram lenses” as appropriate) 11 are provided. Hereinafter, a method for producing the screen system 1 having such a configuration will be specifically described.

<Photopolymer photosensitive material>
The photopolymer photosensitive material according to the present embodiment is a refractive index modulation type photopolymer, and is exposed only by a recording process in which interference fringes are recorded by exposing two coherent light beams to interference. It is preferable to use a material that causes a change in refractive index such that the difference between the refractive index and the refractive index of the unexposed portion is at least 0.001. It is essential that a wet development process for amplifying the difference in refractive index is unnecessary, but it is preferable to use a process that does not require a dry development process using light, heat, or the like.

  Furthermore, as a photopolymer component, a photopolymer composition capable of having a large refractive index change when recording the intensity distribution of light and dark of interference fringes obtained by interfering with light having excellent coherence as a change in refractive index. As the product, (A) a radical polymerizable monomer containing at least one unsaturated double bond capable of radical polymerization, and (B) a cationic polymerizable monomer and / or (C) a binder polymer are preferably used. It is done.

  As a more suitable photopolymer composition, (D) polymerization of the radical polymerizable compound (A) is initiated by irradiation of interference fringes obtained by interference of coherent first light having a visible light wavelength region. When it contains a photo radical polymerization initiator, (E) a photosensitizing dye that sensitizes the photo radical polymerization initiator, and (B) a cationic polymerizable compound, (F) a wavelength region different from that of the first light A photocationic polymerization initiator that initiates polymerization of the cationically polymerizable compound (B) by irradiation with a second light having a refractive index of (A) the radically polymerizable compound is (B) the cationically polymerizable compound and (C) A photopolymer composition adjusted to be larger than the weighted average value of the refractive index with the binder polymer.

  The cationic photopolymerization initiator (F) initiates polymerization of the cationic polymerizable monomer (B) by irradiation with the second light, but is sensitive to irradiation of interference fringes obtained by interference with the first light. Is preferably low and does not substantially initiate the polymerization of the cationically polymerizable monomer (B).

Radical polymerizable monomer (A)
The radical polymerizable monomer (A) used in the present invention has compatibility when the composition according to the present invention is prepared together with the cationic polymerizable monomer (B) and / or (C) binder polymer used in the present invention. A wide range of compounds can be used as long as they are present, but the non-gaseous, ie, liquid or solid radically polymerizable compound (A) having a boiling point of 100 ° C. or higher at normal pressure is preferred.
In particular, (meth) acrylic monomers, vinyl monomers, and (meth) allyl monomers having an ethylenically unsaturated double bond are preferred. These may be used alone or in combination of two or more.

Examples of (meth) acrylic monomers include 2-hydroxyethyl (meth) acrylate, isoamyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, ethoxyethylene glycol (meth) acrylate, methoxytriethylene glycol (meta ) Acrylate, phenoxy (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, 2,4,6-tribromophenoxy (meth) acrylate, 2-naphthyl (meth) acrylate, nonylphenol polyethylene glycol (meth) acrylate, tetrahydrofurfuryl (Meth) acrylate, isobornyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-acryloyloxye Lusuccinic acid, 2-acryloyloxyethylphthalic acid, neopentyl glycol acrylic acid benzoate, 9H-carbazole-9-ethyl (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1 , 6-hexanediol di (methane acrylate, neopentyl glycol di (meth) acrylate, dimethylol-tricyclodecane di (meth) acrylate, bisphenol A ethylene oxide adduct di (meth) acrylate, glycerin di (meta ) Acrylate, bisphenoxyethanol full orange (meth) acrylate, bis (4- (meth) acryloylthiophenyl) sulfide, pentaerythritol tri (meth) acrylate, tetramethylol meta Tetra (meth) acrylate, dipentaerythritol hexa (methane acrylate, trimethylolpropane acrylic acid benzoate, etc.).
Furthermore, a compound suitable as a radical polymerizable compound (A) having a 9,9-diarylfluorene skeleton and containing at least one unsaturated double bond capable of radical polymerization, which is solid at ordinary temperature and pressure. Specific examples include 9,9-bis [4- (3-acryloyloxy-2-hydroxy) propoxyphenyl] fluorene, 9,9-bis (4-methacryloyloxyphenyl) fluorene, 9,9-bis (4- Acryloyloxyphenyl) fluorene, 9,9-bis [4- (2-methacryloyloxyethoxy) phenyl] fluorene, 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene, 9,9-bis { 4- [2- (3-acryloyloxy-2-hydroxy-propoxy) -ethoxy] phenyl} fluorene, Examples include 9,9-bis [4- (3-acryloyloxy-2-hydroxy) propoxy-3-methylphenyl] fluorene, acrylic acid adduct of glycidyl ether of 9,9-bis (4-hydroxyphenyl) fluorene, and the like. be able to.
Further, it may be an oligomer having a dimer or trimer of the above compound.

Examples of vinyl monomers include vinyl acetate, 4-vinylaniline, 9-vinylanthracene, 9-vinylcarbazole, 4-vinylanisole, vinylbenzaldehyde, vinylbenzoate, vinylbenzil chloride, 4-vinylbiphenyl, vinyl Bromide, N-vinylcaprolactam, vinyl chloroformate, vinylcrotonate, vinylcyclohexane, 4-vinyl-1-cyclohexenediepoxide, vinylcyclopentane, vinyldecanoate, 4-vinyl-1,3-dioxolane 2-one, vinyl carbonate, vinyl trithiocarbonate, vinyl 2-ethylhexanoate, vinyl ferrocene, vinylidene chloride, vinyl formate, 1-vinyl imidazole, 2-vinyl naphthalene, vinyl neodecano , 5-vinyl-2-norbornene, 4- (vinyloxy) butylbenzoate, 2- (vinyloxy) ethanol, 4-vinylphenyl acetate, vinyl pivalate, vinyl propionate, 2-vinylpyridine, 1-vinyl-2 -Pyrrolidinone, vinyl sulfone, vinyl trimethylsilane, bis (4-vinylthiophenyl) sulfide and the like.
Further, it may be an oligomer having a dimer or trimer of the above compound.

Examples of (meth) allyl monomers include (meth) allylphenylsulfone, (meth) allylethoxysilane, (meth) allyltrimethoxysilane, (methaneallyl 2, 4, 6-tribromophenyl ether, 2, 2, -di (Meth) allylbisphenol A, di (meth) allyldimethylsilane, di (meth) allyldiphenylsilane, di (meth) allylphenyl phosphine, di (meth) allyl phthalate, di (meth) allyl dicarbonate, di Examples include (meth) allyl succinate.
Further, it may be an oligomer having a dimer or trimer of the above compound.

  Preferable examples of the radical polymerizable compound (A) include phenoxyethyl acrylate, 2, 4, 6-tribromophenoxy (methane acrylate, 2-naphthyl (meth) acrylate, bisphenoxyethanol full orange (meta ) Acrylate.

Cationic polymerizable monomer (B)
The cationically polymerizable monomer (B) used in the present invention is preferably compatible with any other components, has a refractive index as low as that of the radically polymerizable monomer (A), and is liquid at normal temperature and pressure. . By using such a cationically polymerizable monomer, the entire composition is sufficiently compatible before hologram recording, but diffusion transfer of the radically polymerizable monomer (A) is likely to occur as hologram recording is started. . Furthermore, by selecting a material having a low refractive index, the separation from the cationically polymerizable monomer (B) by the diffusion transfer of the radically polymerizable monomer (A) can be carried out with little separation between them. A refractive index difference (refractive index modulation) can be obtained. The cationic polymerizable monomer (B) is polymerized by the reaction of the cationic polymerization initiator (F) by irradiating the second light (preferably ultraviolet light) having a wavelength region different from that of the first light (preferably visible light). .

  Specific examples of the cationically polymerizable monomer (B) include compounds having at least one oxirane structure or oxetane structure in one molecule, or both. Preferred cationic polymerizable monomers (B) are exemplified below.

  Glycidyl ethers; phenyl glycidyl ether, 2-ethylhexyl glycol glycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neonenethyl glycol di Glycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, hydrogenated bisphenol A diglycidyl ether, 2.2-dibromoneopentyl glycol diglycidyl ether.

  Oxetane compounds; 3-ethyl-3-hydroxymethyloxetane, 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, 3-ethyl-3- (phenoxymethyl) oxetane, di [ 1-ethyl (3-oxetanyl)] methyl ether, 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane, 3-ethyl-3-{[3- (triethoxysilyl) propoxy] methyl} oxetane, oxetanyl Silsesquioxysan, phenol novolac oxetane.

  Spiro orthoesters, spiro orthocarbonates, bicycloorthocarbonates and 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate with little polymerization shrinkage can also be used.

  It may be a dimer or trimer oligomer of the above examples. These may be used alone or in combination of two or more. In particular, when a mixture of an oxirane compound and an oxetane compound is used, the cationic polymerization rate increases and a high molecular weight polymer is formed.

Binder polymer (C)
The binder polymer (C) used in the present invention only needs to be compatible with the radical polymerizable compound (A) and the cationic polymerizable compound (B) and can be completely dissolved in the organic solvent. Typical examples include a homopolymer of a monomer having an ethylenically unsaturated double bond, or a copolymer of the monomer and a copolymerizable monomer copolymerizable therewith, a diphenol compound and a dicarboxylic acid compound. Selected from the group consisting of a condensation polymer, a polymer having a carbonate group in the molecule, a polymer having a -SO2- group in the molecule, a cellulose derivative, and a combination of two or more thereof.

  Specific examples of the binder polymer include polyvinyl acetate, polyvinyl butyrate, polyvinyl formal, polyvinyl carbazole, polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polymethyl methacrylate, polyethyl acrylate, polybutyl acrylate, polymethacrylonitrile, Polyethyl methacrylate, polybutyl methacrylate, polyacrylonitrile, poly-1,2-dichloroethylene, ethylene-vinyl acetate copolymer, syndiotactic polymethyl methacrylate, poly-α-vinyl naphthalate, polycarbonate, cellulose acetate, cellulose triacetate Cellulose acetate butyrate, polystyrene, poly-α-methylstyrene, poly-o-methylstyrene, poly-p- For methylstyrene, poly-p-phenylstyrene, poly-2,5-dichlorostyrene, poly-p-chlorostyrene, poly-2,5-dichlorostyrene, polyarylate, polysulfone, polyethersulfone, styrene-acrylonitrile Polymer, styrene-divinylbenzene copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, ABS resin, polyethylene, polyvinyl chloride, polypropylene, polyethylene terephthalate, polyvinyl pyrrolidone, polyvinylidene chloride, hydrogenated Styrene-butadiene-styrene copolymer, transparent polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, a copolymer of (meth) acrylic acid cycloaliphatic ester and methyl (meth) acrylate, and the like.

A binder polymer may be further contained in order to increase the film thickness and provide film flexibility.
The above-mentioned examples of the binder polymer (C) may be used alone or in combination of two or more.

  The binder polymer (C) preferably has a glass transition temperature (Tg) of 100 ° C. or higher.

  The binder polymer (C) can be variously selected depending on the use and application of the hologram. In order to obtain optical properties such as good film formability and diffraction efficiency, polyvinyl acetate, polyvinyl butyrate, cellulose acetate butyrate, ethylene-vinyl acetate copolymer, polymethyl methacrylate, polystyrene, polyvinyl formal, etc. are preferably used. It is done.

  Polyvinyl acetate, polymethyl methacrylate, (meth) acrylic acid cycloaliphatic ester and methyl (meth) acrylate copolymer to obtain better optical properties such as heat resistance, film formability and diffraction efficiency Etc. are preferably used.

  Laser light emitted from a laser light source such as He—Ne (wavelength 633 nm), YAG (wavelength 532 nm), Ar (wavelength 515, 488 nm), He—Cd (wavelength 442 nm) is used as the photopolymerization initiator (D). Those that absorb radicals and generate radicals can be suitably used. Examples of such photopolymerization initiators include carbonyl compounds, amine compounds, arylaminoacetic acid compounds, organic tin compounds, alkylaryl boron salts, onium salts, iron arene complexes, trihalogenomethyl-substituted triazine compounds, organic peroxides. , Bisimidazole derivatives, titanocene compounds, combinations of these photopolymerization initiators and photosensitizing dyes, and the like can be suitably used. Examples of the carbonyl compound include benzyl, benzoin ethyl ether, benzophenone, 3,3 ′, 4,4′-tetra (tert-butylperoxycarbonyl) benzophenone, diethoxyacetophenone, and the like.

  As the photosensitizing dye (E), mihiraketone, acridine yellow, merocyanine, methylene blue, camphorquinone, eosin, decarboxylated rose bengal and the like can be suitably used. As the photosensitizing dye, any substance that absorbs light in the visible region may be used. Besides the above, for example, cyanine derivatives, merocyanine derivatives, phthalocyanine derivatives, xanthene derivatives, thioxanthene derivatives, acridine derivatives, porphyrin derivatives, Coumarin derivatives, base styryl derivatives, ketocoumarin derivatives, quinolone derivatives, stilbene derivatives, oxazine derivatives, thiazine dyes, etc. can also be used. Furthermore, “Dye Handbook” (Okawara Shin et al., Kodansha, 1986), “Functionality Photosensitizing dyes described in “Dye Chemistry” (Shin Okawara et al., CMC, 1983) and “Special Functional Materials” (Chemical Ikemori et al., CMC, 1986) can also be used. These photosensitizing dyes may be used alone or in combination of two or more.

  The organic solvent is effective for improving the film forming property, etc., in addition to adjusting the viscosity and compatibility of the photopolymer photosensitive material. For example, acetone, xylene, toluene, methyl ethyl ketone, tetrahydrofuran, benzene, methylene chloride, dichloromethane, Chloroform, methanol, etc. can be used. However, water cannot be used because it inhibits viscosity adjustment, compatibility adjustment, film-forming property, and the like. Water cannot be used as a medium even in emulsion form. The amount of the organic solvent (solvent) used is a total of 100 of the radical polymerizable compound (A), the cationic polymerizable compound (B) and / or the binder polymer (C), and the photopolymerization initiator (D and / or F). It is the range of about 1-1500 weight part with respect to a weight part. Moreover, in order to control the polymerization rate and molecular weight of the radical polymerizable compound (A), a small amount of a thermal polymerization inhibitor or a chain transfer agent may be added.

  Examples of the thermal polymerization inhibitor include hydroquinone, p-methoxyphenol, tert-butylcatechol, naphthylamine, diphenylpicrylhydrazine, diphenylamine and the like which have a function of eliminating the generated polymerization active species.

  Examples of chain transfer agents include α-methylstyrene dimer, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, tert-butyl alcohol, n-butanol, isobutanol, isopropylbenzene, ethylbenzene, chloroform, methyl ethyl ketone, propylene, chloride. Vinyl etc. can be mentioned.

<Adjustment of photopolymer photosensitive material>
To prepare the photopolymer photosensitive material according to this embodiment described above, a radically polymerizable compound (A), a cationically polymerizable compound (B) and / or a binder polymer (C) soluble in an organic solvent, What is necessary is just to put a photoinitiator (D and / or F) etc. in organic-resistant solvent containers, such as a glass beaker, and to stir the whole. In this case, in order to promote dissolution of the solid component, it may be heated to, for example, about 40 to 90 ° C. within a range in which the composition is not denatured.

<Method for producing hologram recording medium>
The hologram recording medium (before hologram recording) using the photopolymer photosensitive material according to the present embodiment is a two-layer structure comprising a photopolymer photosensitive material applied to one side of a substrate and the resulting coating film (recording layer) and the substrate. It is obtained by producing the recording medium. Alternatively, as a preferred embodiment, as shown in FIG. 3, a recording medium having a three-layer structure may be prepared by covering a recording layer 1B on a substrate 1A with a film-like, sheet-like or plate-like protective material 1C. good.

  When an organic solvent is used in the preparation process of the photopolymer photosensitive material, a radical polymerizable compound (A), a cationic polymerizable compound (B) and / or a binder polymer (C) soluble in an organic solvent, a photopolymerization initiator ( D and / or F) and other optional components (photosensitizing dye, thermal polymerization inhibitor and chain transfer agent) are dissolved in an organic solvent (solvent), and the resulting solution is applied onto the substrate. Thereafter, the recording layer may be formed by evaporating the solvent. When the recording layer is covered with a protective material (see FIG. 3), it is preferable to remove the organic solvent by air drying or evaporation under reduced pressure before coating the protective material.

  As a substrate on which the photopolymer photosensitive material is applied, an optically transparent material such as glass or quartz, or a transparent resin such as polyethylene terephthalate (PET), acrylic resin, polycarbonate, polyolefin, alicyclic polyolefin, or the like is used. Can do. The thickness of the substrate is preferably 0.02 to 10 mm. The substrate is not necessarily flat, and may be bent, curved, or have a concavo-convex structure on the surface. The protective material can also be formed from the same optically transparent material as the substrate. The thickness of the protective material is preferably 0.02 to 10 mm.

  As a coating method of the photopolymer photosensitive material, gravure coating, roll coating coating, bar coating coating, spin coating coating or the like can be used. Then, coating is performed so that the thickness of the recording layer after removal of the solvent is 1 to 500 μm, preferably 5 to 50 μm.

<Recording method of hologram>
In order to record the hologram screen and the hologram lens on the hologram recording medium manufactured as described above, a two-beam interference exposure method is used in the present embodiment. Hereinafter, a more specific description will be given with reference to FIGS. 4, 5, and 6.

<Recording method of hologram screen>
FIG. 4 is a schematic configuration diagram showing an example of an optical system for recording a hologram screen on a hologram recording medium. As shown in FIG. 4, coherent light (laser light) having a wavelength emitted from the laser light source 10 in the range of 200 to 800 nm is split into two light beams using a beam splitter 20 or the like. One of the light beams L1 is referred to as reference light, and the other light beam L2 is referred to as object light. Then, the object light L2 is deflected by using the reflection mirror 30 or the like so as to be again combined with the reference light L1 on the hologram recording medium 100. The hologram recording medium 100 is arranged at a position where an interference fringe can be formed by combining the reference light L1 and the deflected object light L2. In this case, the angle (set diffraction angle) formed by the reference light and the object light can be freely selected in the range of 0 ° to 180 °. The reference light L1 and the object light L2 are each irradiated with a wave front having a well-shaped shape by the aperture 50 or the like after the diameter is enlarged about 10 to 40 times by the objective lens 40 or the like. A diffusing plate 90 is installed in front of the hologram recording medium 100 to allow diffused light to enter. Here, with respect to the reference light L1, the convergent light is converted into projection light using a lens (convex lens) 70. It is also possible to use transmitted light (object light) from a master hologram obtained by irradiating light onto a volume phase master hologram in which information on the object light L2 is recorded in advance.

In the above optical system arrangement, when laser light is irradiated from the laser light source 10 for about several minutes, interference fringes between the reference light L1 and the object light L2 to be a hologram are recorded on the hologram recording medium 100. The amount of laser light is preferably 0.1 to 10,000 mJ / cm ² , more preferably 1 to 1,000 mJ / cm ² in terms of the product of light intensity and irradiation time.

  A diffusion plate such as ground glass is installed between the hologram recording medium 100 and the object light L2. It is preferable that the diffusion plate be as close to the hologram recording medium 100 as possible, but it is necessary to provide an interval so that the reference light is irradiated so that interference fringes can be formed on the hologram recording medium 100.

  FIG. 5 is a schematic configuration diagram illustrating an example of an optical system for recording a hologram lens on a hologram recording medium. As shown in FIG. 5, coherent light (laser light) having a wavelength emitted from the laser light source 10 in the range of 200 to 800 nm is split into two light beams using a beam splitter 20 or the like. One of the light beams L1 is referred to as reference light, and the other light beam L2 is referred to as object light. Then, the object light L2 is deflected by using the reflection mirror 30 or the like so as to be again combined with the reference light L1 on the hologram recording medium 100. The hologram recording medium 100 is arranged at a position where an interference fringe can be formed by combining the reference light L1 and the deflected object light L2. The reference light L1 and the object light L2 are magnified about 10 to 40 times by the objective lens 40, respectively, and then the wave front is neatly shaped by the pinhole 50, and further diffused light is emitted by the collimator lens 60, etc. It is preferable to convert it into parallel light. Here, for the object light L2, parallel light is converted into convergent light using a lens (plano-convex lens) 70. In order to obtain the object light L2 that converges in this way, the transmitted light (object light) from the master hologram obtained by irradiating the volume phase master hologram on which the information of the object light L2 is recorded in advance is used. It is also possible.

In the above optical system arrangement, when laser light is irradiated from the laser light source 10 for about several seconds, interference fringes between the reference light L1 and the object light L2 to be a hologram are recorded on the hologram recording medium 100. The amount of laser light is preferably 0.1 to 10,000 mJ / cm ² , more preferably 1 to 1,000 mJ / cm ² in terms of the product of light intensity and irradiation time.

  In order to produce a plurality of hologram lenses recorded as described above with high positional accuracy for each predetermined region of the photopolymer photosensitive material (for each predetermined region of the hologram recording medium 100), the hologram recording medium 100 is moved in the vertical direction and The laser beam is placed and fixed on a YZ stage that can be moved independently in the horizontal direction, and the amount of movement of the YZ stage (the amount of movement of the hologram recording medium 100) is controlled by a personal computer or the like. Is preferably exposed. Further, in order to accurately set the dimensions of each element hologram to be produced, a mask (light-shielding mask) 300 is placed between the hologram recording medium 100 and the incident reference light L1 and object light L2 as much as possible. It is preferable to place it close to or in contact with 100. If there is a gap between the mask 300 and the hologram recording medium 100, the size of the hologram lens to be recorded is not reflected on the hologram recording medium 100, and a photo around the hologram lens to be originally recorded due to light diffusion. When light is irradiated to a polymer photosensitive material or hologram lens, and light is irradiated to an element hologram that has already been recorded, diffraction efficiency decreases due to overexposure, or light is irradiated to an unrecorded photopolymer photosensitive material This is because pre-exposure is performed, and as a result, it becomes difficult to produce a screen with uniform brightness.

  As the mask 300, a light shielding plate in which a portion corresponding to the dimension of the hologram lens to be recorded is cut out, or a portion other than the portion corresponding to the dimension of the hologram lens of the transparent substrate, which has been subjected to chromium deposition or the like can be used. In any case, it is preferable to use one having the smallest possible thickness. When the thickness of the mask 300 is large, light is applied to the inner wall of a light transmitting region (for example, a cutout portion of the light shielding plate), and the reflected light further interferes with the interference fringes of the reference light L1 and the object light L2. Things happen. As a result, the brightness of the produced hologram lens becomes non-uniform, and streaks and turbidity occur in the peripheral portion of the hologram, which is not preferable.

<Light source for hologram recording>
As a light source for hologram recording according to the present embodiment, light emitted from a light source is irradiated to a photopolymerization initiator contained in a photopolymer photosensitive material or a photopolymerization initiator system comprising a combination of a photopolymerization initiator and a photosensitizing dye. In this case, any material that induces polymerization of the polymerizable compound with electron transfer may be used. Examples of such a light source include a high pressure mercury lamp, an ultra high pressure mercury lamp, a low pressure mercury lamp, a xenon lamp, a metal halide lamp, and the like. These light sources can be suitably used particularly when copying information of the produced hologram screen and hologram lens to another hologram recording medium using a master hologram.

  Further, as described above, a laser light source can be used as the light source for hologram recording according to the present embodiment. The laser beam emitted from the laser light source has a single wavelength and has coherence (coherence), and therefore can be suitably used for hologram recording (interference fringe recording). As a more preferable light source, a light source that is more excellent in coherence, for example, an optical element such as an etalon mounted on the laser light source and the frequency of the single wavelength is changed to a single frequency can be exemplified.

  As a typical laser light source, a laser light source having an oscillation wavelength of 200 to 800 nm, specifically Kr (wavelength 647 nm), He—Ne (wavelength 633 nm), Ar (wavelength 514.5 nm, 488 nm), YAG (wavelength 532 nm) And a laser light source such as He-Cd (wavelength 442 nm). These laser light sources may be used alone or in combination of two or more. The laser light source may be a type that oscillates continuous light or a type that pulsates at a constant or arbitrary interval.

  A hologram screen and a hologram lens are produced by the production method described above, and function to diffract the irradiated light beam in a specific direction according to the interference fringes recorded on the hologram. 6A and 6B are explanatory views for explaining the diffraction function of the hologram lens. FIG. 6A is a side view of the hologram lens 11, and FIG. 6B is a plan view of the hologram lens 11. FIG. As shown in FIG. 6, when the created hologram lens 11 is irradiated with light (conjugate illumination light) L1 ′ conjugate with reference light L1 (see FIG. 5) at the time of interference fringe recording, the transmitted light is reflected by interference fringes. It is emitted from the hologram lens 11 as diffracted light (conjugated diffracted light) L2 ′ conjugate with the object light L2 (see FIG. 5) at the time of recording. In this embodiment, the example in which the conjugate illumination light L1 ′ is irradiated as the reproduction light has been described. However, the present invention is not limited to this, and the reference light L1 at the time of interference fringe recording may be irradiated as the reproduction light. In this case, the object light L2 is emitted as the light transmitted through the hologram lens 11.

  The screen system 1 shown in FIG. 7 is configured using the hologram screen and the hologram lens according to the present embodiment described above. The focal length may be adjusted by inserting a transparent plate 1a having an appropriate thickness between the hologram screen 12 (diffusion screen) and the hologram lens 11. Furthermore, as shown in FIG. 8, transparent protective substrates 1 d may be attached to both surfaces of the screen system 1.

  In order to display a three-dimensional image using the screen system 1, the point light source may be reproduced using the projector 9 with respect to the screen system 1, as shown in FIG. Specifically, a projector is constituted by a light source and a digital micromirror device (DMD) as an element that functions as the mask, and the amount of reflected light emitted from the light source is independent for each element of the device. A configuration in which a projector is configured by using a separately controlled configuration or a liquid crystal display (LCD) as a light source and a mask, and a mask function is realized by independently controlling the density of each pixel of the display is adopted. It is possible. The dimension of each element hologram 11 is preferably a dimension corresponding to a plurality of elements (pixels) of the DMD or LCD (for example, 3 × 3 to 8 × 8). Corresponds to several tens of μm to several mm.

  Hereinafter, the features of the present invention will be further clarified by showing examples.

<Production of hologram recording medium 1>
1.08 g of 9,9-bis [4- (3-acryloyloxy-2-hydroxy) propoxyphenyl] fluorene (single refractive index: 1.63) (weight percentage based on the total composition: 28.1 wt%), Ethylene glycol diglycidyl ether (refractive index of simple substance: 1.46) 1.05 g (27.4% by weight), polymethylmethyl methacrylate (refractive index of simple substance: 1.49) 1.25 g (32.6% by weight) 3,3 ′, 4,4′-tetra (tert-butylperoxycarbonyl) benzophenone 0.25 g (6.5 wt%), cyanine dye (2,5-bis [(4-diethylamino) -2- Methylbenzylidene] cyclopentanone) 0.0082 g (0.2 wt%), triarylsulfonium compound (Asahi Denka Kogyo Co., Ltd., “SP-170”, salt hexa Le Oro antimonate) 0.2 g (5.2 wt%), and acetone 5g mixed at room temperature as a solvent, to prepare a photopolymer photosensitive material 1.

  The adjusted photopolymer photosensitive material 1 is applied to one side of a 103 mm × 128 mm glass substrate (MATSUNAMI MICRO SLIDE GLASS) by spin coating so that the thickness after drying is 20 to 25 μm, and then subjected to heat treatment. Thus, the solvent was removed from the coating layer to produce a recording medium 1 having a two-layer structure comprising a substrate and a recording layer.

  Further, a hologram recording medium having a three-layer structure was manufactured by coating a PET film having a thickness of 50 μm as a protective material on the recording layer.

<Production of hologram screen>
After the laser beam emitted from the YAG (wavelength 532 nm) laser light source is split by a beam splitter, one beam is used as a projection beam (reference beam) using a convex lens and an aperture, and the other beam is deflected using a mirror A parallel lens (object beam) was obtained using a convex lens and an aperture. A ground glass was placed between the convex lens and the hologram recording medium, and the hologram recording medium was placed so that the object light and the reference light form interference fringes on the surface of the hologram recording medium. The angle formed by the two light beams of the reference light and the object light was set to 45 degrees (see FIG. 4).

<Evaluation of hologram screen>
With respect to the hologram screen produced as described above, transmitted light intensity (0 degree transmittance) with respect to 0 degree incident light intensity and 45 degrees using an optical power meter (manufactured by PHOTODYNE, OPTICAL POWER / ENERGY METER, MODEL 66XLA). The transmitted light intensity (45 degree transmittance) with respect to the incident light intensity was measured, and the diffraction efficiency was calculated and evaluated based on the following formula (1).
Diffraction efficiency (%) = (diffracted light intensity / incident light intensity) × 100 (1)

  The produced hologram screen had a very high diffraction efficiency of 0% transmittance of 81% and a very high diffraction efficiency of 45% transmittance of 42% and a diffraction efficiency of 58%.

<Preparation of hologram recording medium 2>
2. 5 g of polymethyl methacrylate (Acrypet VH, manufactured by Mitsubishi Rayon Co., Ltd.) and an acrylic acid adduct of 9,9-bis (4-hydroxyphenyl) fluorene glycidyl ether (manufactured by Nippon Steel Chemical Co., Ltd., “ASF400”) 9 g, 6 g of diethyl sebacate (manufactured by Wako Pure Chemical Industries, “SDE”), 3,3 ′, 4,4′-tetra (tert-butylperoxycarbonyl) benzophenone (manufactured by NOF Corporation, “BTTB-25” ] 1 g, 0.023 g of a cyanine dye (manufactured by Nippon Photosensitizer Co., Ltd., NK6141) or 0.0094 g of base cytilyl dye (manufactured by Nippon Photosensitizer Co., Ltd., NK1819) and 18 g of methyl ethyl ketone as an organic solvent are mixed at room temperature Polymer photosensitive material 2 was prepared

  The adjusted photopolymer photosensitive material 2 is applied to one side of a 103 mm × 128 mm glass substrate (MATSUNAMI MICRO SLIDE GLASS) by spin coating so that the thickness after drying is 20 to 25 μm, and then subjected to heat treatment. Thus, the solvent was removed from the coating layer to prepare a recording medium 2 having a two-layer structure comprising a substrate and a recording layer.

  Further, a hologram recording medium having a three-layer structure was manufactured by coating a PET film having a thickness of 50 μm as a protective material on the recording layer.

<Production of hologram lens>
A laser beam emitted from a YAG (wavelength: 532 nm) laser light source is divided by a beam splitter, one light is converted into parallel light (reference light) using an objective lens, a pinhole and a collimator lens, and the other light is reflected by a mirror. After being deflected by using the objective lens, a pinhole, a collimator lens, and a plano-convex lens, the light was converged (object light) and then combined again to cause interference.
A mask having an opening of 2 × 2 mm was placed at a position where the interference fringes can be formed, and the hologram recording medium was placed so that the surface of the hologram recording medium (PET film surface) and the mask were in contact with each other. In addition, the hologram recording medium can record interference fringes at any part of the hologram recording medium by mounting and fixing on the YZ stage (ALS-230-C2P, ALZ-230-C2P manufactured by Chuo Seiki). I did it. The angle formed by the two light beams of the reference light and the object light was set to 45 degrees (see FIG. 5).

In this state, the hologram recording medium was exposed, and interference fringes to be a hologram were recorded on the hologram recording medium. The light intensity of each of the object light and the reference light on the hologram recording medium was set to 20.0 mW / cm ² and exposed for 1 second (exposure amount was 40.0 mJ / cm ² ). As a result, a transmission type volume phase hologram having a size of 2 × 2 mm was recorded.

  The 2 × 2 mm volume phase hologram recorded as described above is used as a hologram lens, and the Y-Z stage is used to move the exposure position of the hologram recording medium so that the hologram lenses are adjacent to each other. A total of 1200 lenses, 40 in the axial direction and 30 in the Z-axis direction, were recorded to produce a hologram lens (see FIG. 2).

<Evaluation of hologram lens>
For the hologram lens produced as described above, the incident light intensity and the diffracted light intensity at 45 degrees were measured using an optical power meter (manufactured by PHOTODYNE, OPTICAL POWER / ENERGY METER, MODEL 66XLA). The diffraction efficiency was calculated and evaluated based on the formula (1).
Diffraction efficiency (%) = (diffracted light intensity / incident light intensity) × 100 (1)

The produced hologram lens has a diffraction efficiency as high as 79%.
The produced hologram lens was not colored and was bright without going through a development process and a fixing process. Further, when the film thicknesses of the hologram screen and the hologram lens were measured using a micrometer, the film thickness distribution was uniform and the values were 22 μm and 23 μm, respectively. The recording of the hologram lens was performed only by refractive index modulation, not the unevenness of the recording layer, and was highly transparent with almost no light absorption in the visible light region.

<Evaluation of Screen System 1 for 3D Image Display>
Using the hologram screen produced as described above, the screen system 1 was obtained by superimposing the hologram lens produced above with a transparent acrylic plate as a focal length spacer.
The PET film surface (protective material surface) of the produced screen system 1 is used as a display surface (surface on the viewing side), and light constituting a two-dimensional image is projected from the projector (liquid crystal display) disposed on the back side to the screen system 1. The light transmitted through the screen system 1 is diffracted downward. Since the size of one pixel of the liquid crystal display is 250 μm □, a 2 mm × 2 mm hologram lens is irradiated with light beams emitted from a total of 64 pixels in 8 pixels vertically and horizontally. When the display surface was visually confirmed, it was possible to observe a clear three-dimensional image where it was normally transparent.

<Evaluation of Screen System 2 for 3D Image Display>
A commercially available embossed diffusion plate (manufactured by ZEON Corporation) was used, and the screen system 2 was obtained by superimposing the hologram lens prepared above with a transparent acrylic plate as a focal length spacer.
The hologram lens side of the produced screen system 2 is used as a display surface (viewing side surface), and the screen system 2 is irradiated with light constituting a two-dimensional image from a projector (projector) installed on the back side. It arrange | positioned so that the light which permeate | transmitted the system 2 may be diffracted toward the downward direction.
When the display surface was visually confirmed, a clear three-dimensional image could be observed where it was usually translucent.

FIG. 1 is an explanatory diagram for explaining the concept of a three-dimensional image display method based on a parallax light reproduction method. FIG. 2 is a front view showing a schematic configuration of a screen system for displaying a three-dimensional image according to an embodiment of the present invention. FIG. 3 is a longitudinal sectional view showing a schematic configuration of a hologram recording medium for producing a screen system for displaying a three-dimensional image according to an embodiment of the present invention. FIG. 4 is a schematic configuration diagram showing an example of an optical system for recording a hologram screen on the hologram recording medium shown in FIG. FIG. 5 is a schematic configuration diagram showing an example of an optical system for recording a hologram lens on the hologram recording medium shown in FIG. FIG. 6 is an explanatory diagram for explaining the diffraction function of the hologram lens constituting the three-dimensional image display screen system according to the embodiment of the present invention. FIG. 7 is a schematic sectional view of a screen system for displaying a three-dimensional image according to an embodiment of the present invention. FIG. 8 is a schematic cross-sectional view showing a state in which a protection base is provided in the screen system for displaying a three-dimensional image according to one embodiment of the present invention. FIG. 9 is a schematic view showing a three-dimensional image display apparatus according to an embodiment of the present invention. FIG. 10 is an explanatory diagram for explaining a method of displaying a three-dimensional image according to the present invention with respect to a point light source.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Screen system for 3D image display 8 ... 3D image display apparatus 9 ... Projector 11 ... Volume phase type hologram (hologram lens)
12. Diffusion screen (hologram screen)

Claims (7)

  A three-dimensional image in which the image light projected from the projection device is scattered and diffused by a hologram screen or a diffusing screen, and a three-dimensional image can be viewed by converging the transmitted light of each projected light beam with a hologram lens. A display screen system that records and irradiates without requiring wet development processing by exposing two light beams of reference light and object light to interfere with each other in a predetermined area of the photopolymer photosensitive material applied on the surface. A screen system for displaying a three-dimensional image, wherein a plurality of volume phase hologram lenses for diffracting the emitted light beam in a specific direction are provided. A plurality of volume phase hologram lenses are provided that diffract the irradiated light beam in a specific direction by exposing two light beams of reference light and object light to interfere with each other in a predetermined area of the photosensitive material applied on the surface. A screen system for displaying a three-dimensional image,
The image light of the parallax image projected from the projection device is scattered and diffracted by a hologram screen or a diffusing screen, and then the transmitted light of each projected light beam is imaged by the hologram lens described above to form a three-dimensional image. A screen system for displaying a three-dimensional image.   The three-dimensional image display screen system according to claim 1 or 2, wherein the hologram screen or the diffusion screen is a volume phase hologram screen.   3. The screen system for displaying a three-dimensional image according to claim 1, wherein the hologram screen or the diffusing screen is an embossed hologram screen.   The hologram screen or diffusing screen has a photopolymer as a main component, the transmittance of the hologram screen or diffusing screen with respect to 0 ° incident light is 65% or more, and the transmittance with respect to incident light at a set diffraction angle is 40% or more. The three-dimensional image display screen system according to claim 1, wherein the three-dimensional image display screen system is a display system.   6. The hologram lens according to claim 1, wherein the hologram lens comprises a photopolymer as a main component, and a refractive index distribution is formed by mixing a radical polymerizable monomer and a binder polymer as a composition of the photopolymer. A three-dimensional image display screen system according to claim 1.   A projector for projecting light rays constituting a two-dimensional image to the screen system for displaying a three-dimensional image according to any one of claims 1 to 6, wherein the light projector constitutes each light ray constituting the two-dimensional image. A three-dimensional image display device capable of independently controlling the amount of incident light to the three-dimensional image display screen system.