Abstract: The present invention relates to a method for producing an optical recording medium. In the method, on the surface of a recording layer formed by spin-coating a first coating solution containing a photo-isomerizable component, a second coating solution that contains a photo-isomerizable component that can be isomerized by radiation having the same wavelength as radiation used for isomerizing the photo-isomerizable component contained in the recording layer and incapable of dissolving the recording layer is spin-coated to form an intermediate layer. Since the intermediate layer thus formed cannot be dissolved by the first coating solution, a recording layer is further laminated on this layer. Thus, it becomes possible to make the recording layer thicker and also to provide a high-density recording characteristic.

Abstract: The present invention relates to a method for producing an optical recording medium. In the method, on the surface of a recording layer formed by spin-coating a first coating solution containing a photo-isomerizable component, a second coating solution that contains a photo-isomerizable component that can be isomerized by radiation having the same wavelength as radiation used for isomerizing the photo-isomerizable component contained in the recording layer and incapable of dissolving the recording layer is spin-coated to form an intermediate layer. Since the intermediate layer thus formed cannot be dissolved by the first coating solution, a recording layer is further laminated on this layer. Thus, it becomes possible to make the recording layer thicker and also to provide a high-density recording characteristic.

Abstract: A recording medium including a storage part to hold a medium identifier intrinsic to each recording medium, and a hologram generated using a reference beam modulated with the medium identifier. Preferably, the hologram is fixed on a surface of the recording medium.

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: 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: 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 shredder that shreds a recording medium which includes, on a surface thereof, an image forming portion and a holographic memory portion in which data is recorded. The shredder includes a data destroying unit that destroys at least the data recorded in the holographic memory portion and a shredding unit that shreds the entire recording medium. Thus, when a recording medium to which has been added a holographic memory portion in which useful information is recorded is to be discarded, the data(information) recorded in the holographic memory portion can be safely destroyed so that the data can no longer be read.

Abstract: In the disclosed holographic recording method, when multiplex recording of data of a plurality of pages is performed, exposure time of a hologram of a final page to be recorded is fixed irrespective of a degree of multiplicity while an exposure time of each page is changed and diffraction efficiencies of the holograms of the plurality of pages becomes equal.

Abstract: Information recorded as a hologram in a predetermined position of an optical recording medium is reproduced, and subsequently the reproduced information is re-recorded and retained in the same position as the predetermined position as a hologram. Alternatively, information recorded as a hologram in a predetermined position of an optical recording medium is reproduced, and subsequently the reproduced information is re-recorded and retained in a position different from the predetermined position as a hologram easily.

Abstract: A holographic recording method and a holographic recording apparatus capable of selectively rewriting or erasing only desired data without degrading data other than the desired data are provided. Holograms are multiple recorded per file, and page data in one file is multiple recorded, while page data in one file and page data in another file are not multiple recorded. Therefore, only the desired file can be selectively rewritten or erased without degrading the other files.

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: The present invention discloses a hologram erasing method, in which a predetermined hologram is erased by irradiating a predetermined region of a hologram recording medium in which the hologram to be erased is recorded with a reference light beam and a signal light beam holding a random data pattern at the same time. In this method, the signal light beam and the reference light beam interfere with each other in the medium, and a Fourier transform hologram recorded in the region where the interference occurs is destroyed and erased by interference light beam. That is, a data page for erasing including a random pattern is overwritten to erase an original data page. According to the present invention, the hologram recorded in the optical recording medium can be selectively and completely erased in a simple method.

Abstract: Quality of a reproduced light beam is improved, and rewriting and recording are performed at high speed without erasing data. Each page of a hologram is newly recorded so that the maximum point of diffraction light beam intensity in reproducing the newly recorded hologram is located at a position where diffraction light beam intensity from a data page of a hologram which has been previously recorded in a hologram recording medium is minimized at the time of reproducing the data.

Abstract: In a recording layer, a recording track is provided in the form of concentric circles or a spiral along a moving direction of a recording spot. When only specific Fourier transform components in a Fourier transform image of signal light are recorded, a width of the recording track provided in the recording layer is set corresponding to a diffraction order of the Fourier transform component to be recorded. That is to say, according to the diffraction order of the Fourier transform component to be recorded, the width of the recording track is determined within the range satisfying the following relationship. Here w is the width of the recording track, d is a length of one side of one-bit data of the signal light, &lgr; is a wavelength of the signal light, F is a focal distance of a lens system, and n is an integer of 2, 3, or 4.

Abstract: An optical recording medium including a recording layer which is formed into a predetermined shape with a thickness of 0.1 mm to 5 mm and which contains a polyester represented by the following formula (1).

Abstract: An optical recording/reproducing apparatus having excellent resistance against vibration and noise is provided. In recording, coherent light is polarization-modulated with a spatial light modulator to generate signal light and reference light whose polarization directions are crossed at right angles with each other. The signal light permeates a polarizing beam splitter, and is incident to a quarter wavelength plate. The reference light passes through a passing hole, is diffused by a light diffuser and is incident to the quarter wavelength plate. The reference and signal light are converted into circularly polarized light which revolve in directions opposite to each other and condensed by a condenser lens, and then a predetermined area of an optical recording medium is irradiated with the reference and signal light. Thus, the reference and signal light are generated by modulating the incident light from the same light source and are coaxially incident to the polarizing beam splitter.

Abstract: The present invention relates to a method for producing an optical recording medium. In the method, on the surface of a recording layer formed by spin-coating a first coating solution containing a photo-isomerizable component, a second coating solution that contains a photo-isomerizable component that can be isomerized by radiation having the same wavelength as radiation used for isomerizing the photo-isomerizable component contained in the recording layer and incapable of dissolving the recording layer is spin-coated to form an intermediate layer. Since the intermediate layer thus formed cannot be dissolved by the first coating solution, a recording layer is further laminated on this layer. Thus, it becomes possible to make the recording layer thicker and also to provide a high-density recording characteristic.