Hologram recording film and method of manufacturing same, and image display apparatus

Abstract

A hologram recording film manufacturing method includes the steps of obtaining a laminated structure by alternately laminating M (where M≧2) photosensitive material precursor layers including a photosensitive material and at least one (M−1) resin layer on one another, obtaining M photosensitive material layers, where at least two interference fringes with a desired pitch and a desired slant angle are formed on each of the M photosensitive material layers, from the M photosensitive material precursor layers by irradiating the laminated structure with a reference laser light beam and an object laser light beam, and making the slant angles of the M photosensitive material layers different from each other while retaining the pitch value, which is defined on a face of the photosensitive material layer, by irradiating the laminated structure with an energy ray from the laminated structure's one face side, and heating the laminated structure.

The application is claimed as follows: 
     
         1 . A hologram recording film comprising:
 a multilayer structure in which M (where M≧2) photosensitive-material layers made of a photosensitive material and at least one (M−1) resin layer are alternately stacked, the photosensitive-material layers having interference fringes with a desired pitch and slant angle, the resin layer having a different energy ray transmittance or energy ray transmission amount from the photosensitive-material layers, wherein   among the M photosensitive-material layers, values of pitches are identical and slant angles are different on surfaces of the photosensitive-material layers, and   the resin layer is composed of an (M−1) second-photosensitive-material layer made of a second photosensitive material, the second-photosensitive-material layer having interference fringes with a desired pitch and slant angle.   
     
     
         2 . The hologram recording film according to  claim 1 , wherein the resin layer enables slant angles in the individual photosensitive-material layers to be controlled. 
     
     
         3 . The hologram recording film according to  claim 1 , wherein the resin layer contains a material that absorbs an energy ray. 
     
     
         4 . The hologram recording film according to  claim 1 , wherein a reproduction center wavelength in the M photosensitive-material layers is changed in accordance with a value of M. 
     
     
         5 . The hologram recording film according to  claim 4 , wherein a difference between a reproduction center wavelength before irradiation of an energy ray and a reproduction center wavelength after irradiation of an energy ray changes more monotonously as the value of M increases. 
     
     
         6 . An image display device comprising:
 (A) an image forming device including a plurality of pixels arranged in a two-dimensional matrix pattern;   (B) a collimating optical system configured to collimate light beams emitted from the individual pixels of the image forming device; and   (C) an optical device configured to receive, guide, and emit the light beams collimated by the collimating optical system,   the optical device including   (a) a light guiding plate configured to receive the light beams, cause the light beams to propagate therein by total reflection, and emit the light beams,   (b) a first diffraction grating member provided on the light guiding plate and configured to diffract and reflect the light beams received by the light guiding plate so that the light beams received by the light guiding plate are totally reflected in the light guiding plate, and   (c) a second diffraction grating member provided on the light guiding plate and configured to diffract and reflect the light beams propagated in the light guiding plate by total reflection and cause the light beams to be emitted from the light guiding plate, wherein   the first diffraction grating member and the second diffraction grating member are composed of a hologram recording film,   the hologram recording film includes a multilayer structure in which M (where M≧2) photosensitive-material layers made of a photosensitive material and at least one (M−1) resin layer are alternately stacked, the photosensitive-material layers having interference fringes with a desired pitch and slant angle, the resin layer having a different energy ray transmittance or energy ray transmission amount from the photosensitive-material layers,   among the M photosensitive-material layers, values of pitches are identical and slant angles are different on surfaces of the photosensitive-material layers, and   the resin layer is composed of an (M−1) second-photosensitive-material layer made of a second photosensitive material, the second-photosensitive-material layer having interference fringes with a desired pitch and slant angle.   
     
     
         7 . An image display device comprising:
 (A) a light source;   (B) a collimating optical system configured to collimate light emitted from the light source;   (C) scanning means for scanning collimated light emitted from the collimating optical system;   (D) a relay optical system configured to relay the collimated light scanned by the scanning means; and   (E) an optical device configured to receive, guide, and emit the light collimated by the relay optical system,   the optical device including   (a) a light guiding plate configured to receive the light, cause the light to propagate therein by total reflection, and emit the light,   (b) a first diffraction grating member provided on the light guiding plate and configured to diffract and reflect the light received by the light guiding plate so that the light received by the light guiding plate is totally reflected in the light guiding plate, and   (c) a second diffraction grating member provided on the light guiding plate and configured to diffract and reflect the light propagated in the light guiding plate by total reflection and cause the light to be emitted from the light guiding plate, wherein   the first diffraction grating member and the second diffraction grating member are composed of a hologram recording film,   the hologram recording film includes a multilayer structure in which M (where M≧2) photosensitive-material layers made of a photosensitive material and at least one (M−1) resin layer are alternately stacked, the photosensitive-material layers having interference fringes with a desired pitch and slant angle, the resin layer having a different energy ray transmittance or energy ray transmission amount from the photosensitive-material layers,   among the M photosensitive-material layers, values of pitches are identical and slant angles are different on surfaces of the photosensitive-material layers, and   the resin layer is composed of an (M−1) second-photosensitive-material layer made of a second photosensitive material, the second-photosensitive-material layer having interference fringes with a desired pitch and slant angle.   
     
     
         8 . The image display device according to  claim 6 , wherein the resin layer enables slant angles in the individual photosensitive-material layers to be controlled. 
     
     
         9 . The image display device according to  claim 6 , wherein the resin layer contains a material that absorbs an energy ray. 
     
     
         10 . The image display device according to  claim 6 , wherein a reproduction center wavelength in the M photosensitive-material layers is changed in accordance with a value of M. 
     
     
         11 . The image display device according to  claim 10 , wherein a difference between a reproduction center wavelength before irradiation of an energy ray and a reproduction center wavelength after irradiation of an energy ray changes more monotonously as the value of M increases.