Abstract: There is provided a hologram recording method, including generating a signal light which is spatially modulated such that digital data is represented by an image of intensity distribution, irradiating the signal light on an optical recording medium after a Fourier transformation of the signal light such that a zero-order component of the signal light comes into focus at a point removed from the optical recording medium, forming a diffraction grating in the optical recording medium by interference between the zero-order component of the signal light and a high-order component thereof, and recording digital data represented by the signal light as a hologram.

Abstract: The present invention provides an image formation device including: an image reading section which reads an image from an image formation member, at which image formation member the image is formed and a hologram recording medium is mounted, associated information relating to the image being stored as a hologram in the hologram recording medium; an information acquisition section which acquires the stored associated information from the hologram recording medium; an image processing section which processes the image read by the image reading section in accordance with the associated information acquired by the information acquisition section; and an image formation section which forms an image processed by the image processing section.

Abstract: There is provided a hologram recording medium having: a recording layer at which a hologram can be recorded by illumination of writing light; and a protective layer provided on the recording layer in order to protect the recording layer, a water absorbency of the protective layer being less than or equal to 0.01%.

Abstract: An optical recording apparatus comprises: a focusing section that focuses to a transmission type recording medium a recording light beam including a signal light beam and a reference light beam which are radiated from a same direction with a common optical axis; and a focused-position moving section that moves with respect to a direction of the optical axis a focused position where the recording light beam is focused to the transmission type recording medium by the focusing section, wherein an interference fringe formed by the recording light beam is recorded in the transmission type recording medium at each position which is moved by the focused-position moving section.

Abstract: A postprocessing apparatus for conducting postprocessing on an image forming member, including a receiving unit for receiving an image forming member having an image formed thereon, and an attaching unit for attaching a hologram recording medium in which a hologram can be written, to the image forming member. The postprocessing apparatus further includes a recording unit for writing related information corresponding to image formed on the image forming member, onto the hologram recording medium.

Abstract: A hologram recording method includes generating a signal beam with data formed by superimposing pattern data, the pattern data representing a pattern in which a large number of plural kinds of pixels having different tone values are arranged in a two-dimensional manner, on an image data of respective pixels represented by tone values corresponding to density, and recording a hologram by irradiating a converted beam formed by Fourier transformation of the generated signal beam with a lens and a reference beam to an optical recording medium.

Abstract: A hologram recording method is disclosed in which: signal light includes a plurality of arranged reversal regions in which lightness and darkness of plural pixels of a light and dark image is reversed for an intensity distribution of the light and dark image; the signal light is Fourier-transformed; the Fourier-transformed signal light and reference light are illuminated onto an optical recording medium; and the signal light is recorded as a hologram. Also is disclosed an apparatus capable of implementing the hologram recording method, and an optical recording medium usable with the method.

Abstract: There is provided a hologram recording method including: generating light of a pattern in which a plurality of unit blocks, which include at least one pixel and express luminance, are arrayed, the pattern being sectioned into a region of a signal beam and a region of a reference beam, and being generated such that the region of the reference beam includes a plurality of unit blocks whose numbers of pixels are different; collecting the generated light at a common optical system, and illuminating it onto an optical recording medium; and recording, as a hologram, data which the signal beam expresses.

Abstract: A hologram recording material is used for recording information by at least irradiation with light. The hologram recording material includes photoresponsive molecules, liquid crystal molecules, and particles having an average particle diameter of one tenth or less of a wavelength of light used in the information recording.

Abstract: While Fourier transformation of a signal light beam is performed to perform recording during holographic recording so that a focal point is formed outside a holographic recording layer (defocus recording), an aperture is arranged on an outgoing side of the reproduced signal light beam (reproduction light beam), the reproduction light beam is focused at the aperture, and low-order components of a Fourier transform image of the reproduction light beam are selectively transmitted to detect only the transmitted light beam. Therefore, information recorded as the hologram in the holographic recording layer can be reproduced with high S/N ratio from the holographic recording layer added onto a support body, particularly onto a sheet member having non-optical quality such as paper and a plastic card.

Abstract: A hologram recording method for recording information of signal light as holograms in an optical recording medium, which includes illuminating signal light at the optical recording medium; illuminating reference light at the optical recording medium simultaneously with the signal light such that an interference pattern is formed by the signal light and the reference light intersecting in the optical recording medium; and shifting a region in the optical recording medium at which the signal light and the reference light intersect, by shifting an illumination position of the reference light along an optical axis of the signal light, thereby recording a plurality of holograms in the recording medium.

Abstract: A hologram is recorded by irradiating, with a reference light beam, a region corresponding to an intensity distribution of a signal light beam on an optical recording medium. For example, the reference light beam having the intensity distribution which substantially coincides with the intensity distribution of the signal light beam is generated, and only the region which substantially coincides with the region irradiated by the signal light beam (i.e., the signal light beam defocused region) is irradiated with the reference light beam. This enables only the necessary region to be exposed and the regions which need not be exposed not to be exposed. Accordingly, the hologram can be recorded without losing information of the signal light beam and thus high-density recording can be realized.

Abstract: An optical recording method includes providing an optical recording medium capable of forming both a refractive index grating and an absorption grating by light irradiation; Fourier transforming with the same lens a signal beam that represents binary digital data with a brightness image and a reference beam such that they are focused at a point outside the optical recording medium; irradiating the Fourier transformed signal beam and reference beam simultaneously onto the optical recording medium and forming a diffraction grating at the optical recording medium according to an interference fringe between the signal beam and the reference beam, or according to an interference fringe within the signal beam itself, and recording the signal beam as a hologram.

Abstract: There is provided a hologram reconstruction method including: onto an optical recording medium in which a hologram is recorded by simultaneously irradiating the Fourier transformed signal beam representing a digital data with a bright and dark image and removing a DC component and the Fourier transformed reference beam thereon, irradiating a first reference beam for reading out that is the same as the reference beam to generate a first diffracted light generated by the recorded hologram, and synthesizing a DC component of a predetermined phase with the generated first diffracted light to generate a first synthesized light; detecting an inverse Fourier transformed image of the first synthesized light to obtain first image data; irradiating a second reference beam for reading out that differs from the reference beam onto the hologram recorded on the optical recording medium to generate a second diffracted light from the recorded hologram, and synthesizing a DC component of a predetermined phase with the generat

Abstract: A hologram recording method, which records signal light onto an optical recording medium as a hologram, includes: placing a signal light region, which generates signal light, and a reference light region, which generates reference light, symmetrically with respect to an optical axis of coherent light by displaying, on a spatial light modulator which spatially modulates the incident coherent light, a pattern which divides a modulating region into a plurality of regions; generating signal light and reference light by modulating the incident coherent light by the spatial light modulator; simultaneously and coaxially illuminating, onto a reflecting-type optical recording medium, the signal light and the reference light generated from the signal light region and the reference light region disposed symmetrically to one another; and recording the signal light on the optical recording medium as a hologram.

Abstract: In the present invention, a photosensitive layer of an optical recording medium includes a photo-responsive high-molecular compound comprising a photo-responsive group (e.g., an azobenzene derivative) which is geometrically isomerized by light radiation, and a liquid crystal linear mesogen group (e.g., a biphenyl derivative), wherein the photo-responsive group and the linear mesogen group are respectively bonded as side chains. The invention provides an optical recording medium enabling large scale recording by making the photosensitive layer thick without impairing recording characteristics. The photo-responsive high-molecular compound preferably comprises an aromatic ring on a main chain. Further, the photo-responsive high-molecular compound preferably comprises a structural unit which is capable of forming a liquid-crystalline or crystalline polymer and a structural unit which is capable of forming an amorphous polymer.

Abstract: A hologram reproduction method for reproducing a hologram from an optical recording medium in which the hologram is recorded by Fourier transforming a signal light, in which digital data is represented by an image of intensity distribution, and a reference light, and simultaneously irradiating the lights in a state in which a direct current component is removed from at least the Fourier transformed signal light onto the optical recording medium is provided. The method including: irradiating a read out reference light onto the optical recording medium, and generating a diffracted light from the recorded hologram; generating all or a part of a direct current component contained in a Fourier transformed image of the signal light; combining the diffracted light and the generated all or a part of the direct current component, and generating a combined beam; and reproducing the signal light by inverse-Fourier transforming the combined beam.

Abstract: There is provided a data playback method including: acquiring first image data by illuminating reference light for reading onto an optical recording medium on which a hologram has been recorded by Fourier transforming and simultaneously illuminating reference light and signal light expressing digital data as a light-and-dark image, and detecting an inverse Fourier-transform image of diffracted light which is diffracted by the recorded hologram; acquiring second image data, which is a reversal image of the first image data, by generating combined light by combining the diffracted light and a dc component whose phase is different than a phase of a dc component of the signal light included in the diffracted light, and detecting an inverse Fourier-transform image of the combined light; and computing a difference in luminance for each pixel of the light-and-dark image, by carrying out computing processing by using the first and second image data.

Abstract: A holographic recording medium has at least a recording layer with a thickness of L which comprises a recording layer material having an absorption coefficient of ? and containing a photorefractive material, wherein the optical density ?L represented by the product of the absorption coefficient ? and the thickness L is in the range from 0.3 to 2.0.

Abstract: There is proposed a hologram recording method that includes: generating signal light by superimposing a periodic intensity distribution or phase distribution on an intensity distribution of light that expresses binary digital data as a light/dark image; Fourier transforming the signal light; illuminating Fourier transformed signal light and reference light simultaneously on an optical recording medium; and recording the signal light as a hologram.