Dai Nippon Printing Co., Ltd.

Tsuyoshi Hotta

Kenji Ueda

Yukio Taniguchi

Atsushi Sekiguchi

Hideyuki Iriyama

Yuko Kuwabara

Toshikazu Segawa

Nobuhiko Ichikawa

Masachika Watanabe

Shingo Nishikawa

Hideaki Morita

Daijiro Kodama

Osamu Takekoh

The hologram recording sheet according to the invention is made up of a base film and hologram sensitive materials sensitive to different wavelength regions formed therein in a desired pattern, or a film and at least two hologram recording sensitive materials sensitive to different wavelength regions laminated on the film with a transparent plastic spacer layer located therebetween, thereby enabling the required diffraction light wavelengths to be recorded on the required sites without producing unnecessary interference fringes. At least two hologram recording sensitive materials sensitive to different wavelength regions are formed on different sites on a film in dotted or striped configuration, the size of which is up to 200 mm or at least twice as large as the thickness of the sensitive material layers, thereby enabling regions diffracting light of different wavelengths to be formed in the form of independent sets of interference fringes.

Hologram recording sheet, holographic optical element using said sheet, and its production process

A method of fabricating a hologram having a pattern made up of pixels in which a photosensitive material for forming a hologram is stacked on either a reflection-type hologram or a transmission type hologram. According to one aspect of the invention, the photosensitive material is stacked on a reflection-type relief hologram and reconstructing illumination light of a given wavelength is struck on the reflection-type relief hologram through the photosensitive material, so that interference fringes produced by interference of the light diffracted from the reflection type relief hologram and the incident light are recorded in the photosensitive material. According to another aspect of the invention, the photosensitive material is stacked on a transmission-type hologram, and reconstructing illumination light of a given wavelength is struck on a side of the transmission type hologram that is not opposite to the volume hologram photosensitive material, so that interference fringes produced by interference of light diffracted from the transmission type hologram and reference light incident on the photosensitive material are recorded in the photosensitive material. According to a third aspect of the invention, the photosensitive material is stacked on a transmission type hologram, and reconstructing illumination light of a given wavelength is struck on a side of the transmission type hologram that is not opposite to the photosensitive material, so that interference fringes produced by interference of light diffracted from the transmission type hologram and zero-order transmitted light are recorded in the photosensitive material, and a reflecting layer is provided on a back side of the photosensitive material.

Reflection type diffuse hologram, hologram for reflection hologram color filters, etc., and reflection type display device using such holograms

A reflection type color display device and a reflection type of direct-view color display device are provided. The reflection type color display device includes a spatial light modulator having a collection of pixels and a controllable transmittance per pixel, with a reflection type hologram color filter located on the back side of the modulator. The reflection type of direct-view color display device includes a hologram color filter which has an array of light-collecting holograms. Each of the light-collecting holograms has its own hologram color filter, reflection type hologram, and transmission type spatial light modulator located between the hologram color filter and the reflection type hologram.

A liquid crystal display apparatus and liquid crystal projection display apparatus, which employ a hologram color filter, and which are designed so that the illuminating light utilization efficiency is improved to a considerable extent, and that a color image can be faithfully displayed with excellent color reproducibility without uneven color or other similar problem. A color liquid crystal display apparatus ( ) has a hologram ( ), which diffractively disperses incident light so as to emanate light rays in different wavelength regions at a predetermined spatial period, as a color filter, and a liquid crystal display device ( ). The display apparatus ( ) is illuminated by white parallel back light ( ) from an illuminator ( ). A displayed image which is modulated in the color liquid crystal display apparatus ( ) is passed through a field lens, which is disposed in the vicinity of the display apparatus ( ), and formed as an enlarged image on a screen ( ) for display through a projection lens ( ). A short-wavelength cut-off filter whose transmittance for a wavelength not longer than 430 nm is not higher than 5% is disposed at a position in an optical path extending from a lamp ( ) to the screen ( ), thereby preventing crosstalk of colors which might otherwise occur when light which should be incident on a pixel assigned to display blue undesirably enters a pixel which is adjacent to the pixel for blue, and thus making it possible to display a faithful color image.

Liquid crystal display apparatus and liquid crystal projection display apparatus which employ hologram color filter

The present invention provides a hologram color filter having a drastically decreased dependence of diffraction efficiency on wavelength and well corrected for a color balance among the three colors R, G and B comprising an array of converging element holograms 5&prime;, each of which enables white light incident at a given angle &thgr; with respect to a normal line of a hologram recorded surface thereof to be spectroscopically separated by wavelength dispersion in a direction substantially along the hologram recorded surface, wherein the converging element holograms 5&prime; have each a plurality of hologram pieces and superposed on each other or multi-recorded therein, which, with respect to the white light incident at the given angle &thgr;, have substantially identical spatial wavelength distributions of wavelength dispersion and different peak wavelengths of diffraction efficiency.

Hologram color filter, and its fabrication method

A transmission hologram allowing an illuminating light source for holographic reconstruction to be placed behind the hologram, i.e. on the side opposite to the viewing side, and permitting reconstruction of an image that is bright and clear and has low chromatic dispersion, which is the feature of the reflection type volume hologram. A transmissively viewable reflection hologram has a semitransparent reflecting mirror or a semitransparent reflecting layer placed at either side of a reflection type volume hologram member. The semitransparent reflecting mirror or the semitransparent reflecting layer is integral with or separate from the reflection type volume hologram member.

Transmissively viewable reflection hologram

Hologram recording sheet holographic optical element using said sheet and its production process

Hologram recording sheet, holographic optical element using said sheet,

A holographic optical element or other similar molded article using glass as a substrate is improved in the adhesion between the glass substrate and a resin layer formed thereon so that neither peeling nor change of properties will occur. A holographic optical element (4) is adapted to generate interference fringes of the same pitch as that of tracks formed on a magnetic recording disk or repeated patterns formed on an encoder by interference between two light beams emerging from two different holographic lens regions. The holographic optical element (4) includes a glass substrate (3), a radiation-cured resin layer (2) having a hologram relief pattern on the surface thereof, and a silane coupling agent layer (5) provided between the glass substrate (3) and the radiation-cured resin layer (2).

Molded articles using glass as substrate, such as holographic optical

A liquid crystal display apparatus and liquid crystal projection display apparatus, which employ a hologram color filter, and which are designed so that the illuminating light utilization efficiency is improved to a considerable extent, and that a color image can be faithfully displayed with excellent color reproducibility without uneven color or other similar problem. A color liquid crystal display apparatus (11) has a hologram (5), which diffractively disperses incident light so as to emanate light rays in different wavelength regions at a predetermined spatial period, as a color filter, and a liquid crystal display device (6). The display apparatus (11) is illuminated by white parallel back light (3) from an illuminator (14). A displayed image which is modulated in the color liquid crystal display apparatus (11) is passed through a field lens, which is disposed in the vicinity of the display apparatus (11), and formed as an enlarged image on a screen (19) for display through a projection lens (18). A short-wavelength cut-off filter whose transmittance for a wavelength not longer than 430 nm is not higher than 5% is disposed at a position in an optical path extending from a lamp (15) to the screen (19), thereby preventing crosstalk of colors which might otherwise occur when light which should be incident on a pixel assigned to display blue undesirably enters a pixel which is adjacent to the pixel for blue, and thus making it possible to display a faithful color image.

Growing community of inventors

Tokyo, Japan

Tsuyoshi Hotta