Abstract: In an optical information recording/reproducing apparatus using holography in which a relative inclination between a recording light or a reproducing light and a recording medium is corrected by using a device which is suitable for size-reduction. Provided is an optical information recording/reproducing apparatus for recording/reproducing information to/from a recording medium through irradiating recording light or reproducing light by an objective lens onto a recording medium to/from which information is recorded/reproduced using holography, wherein light ray flux of the recording light or the reproducing light entering an objective lens is parallel-translated according to a relative inclination between the recording light or the reproducing light and the recording medium.

Abstract: It is an object of the invention to improve a recording capacity density by removing part of diffracted light and by making a recording region in relation to a recording medium in the efficient shape. An optical information recording apparatus in which holography is formed in an optical information recording medium by making information light reflected by a spatial modulator interfere with reference light, is provided with a diffracted light removal means which removes part of diffracted light of the reflected light, and whose aperture is in the shape of a square.

Abstract: An optical pick-up device that records and/or reproduces information on an optical information recording medium, through the use of holography, can prevent deterioration of recording and reproduction accuracy due to vibrations from exterior or fluctuations in the relative positional relationship with the recording medium. The optical pick-up device includes a pick-up body and a position adjusting device. The position adjusting device changes the position of the pick-up body in a direction perpendicular to a surface of the recording medium, in a direction parallel to the surface of the recording medium, and in such a direction as to change the inclination of the pick-up body with respect to the surface of the recording medium.

Abstract: An optical-disk recording method, recording apparatus and reproducing apparatus are provided which are capable of continuously recording/reproducing a hologram with ultra-high density. In the case of recording a hologram to a holographic recording area, a holographic recording spot HSP on one track of the holographic recording area and a holographic recording spot HSP on a track adjacent thereto are recorded in circumferentially different positions. At least one holographic recording spot HSP is formed on each track, making the process continuous. Recording is made such that, provided that the holographic recording spot HSP has a diameter D and a multiplex number of holographic recording spots HSP is m, a pitch P between adjacent holographic recording spots HSP is P=D/m. Consequently, it is possible to efficiently record a hologram with density to a holographic recording area of an optical disk recording medium, and to achieve the density increase of holographic recording capacity.

Abstract: An optical information-recording medium 1 is constituted by depositing a quarter-wave plate 4, a hologram-recording layer 3 and a reflection layer 5 on a transparent base plate 2 in this order. Reproducing reference light (P-polarized light) passes through the quarter-wave plate 4 to change into a circularly polarized light, and then the circularly polarized light enters the hologram-recording layer 3, so that the reproducing light (circular polarization) generated from the hologram-recording layer 3 passes through the quarter-wave plate 4 to change into a S-polarized light. On the other hand, stray light SL1 (P-polarized light) resulting from the process in which the reproducing light is reflected from the surface of the base plate or in the inside thereof has an vibration direction different from that in the stray light SL2 (P-polarized light) resulting from the process in which the reproducing reference light goes and returns in the inside of the optical information-recording medium 1.

Abstract: It is an object of the invention to record or reproduce information through the use of holography, attain a small configuration of the optical system for recording or reproduction, and improve the S/N ratio of reproduced information.

Abstract: It is an object of the invention to allow the use of a practical light source to record information in each information recording area of a recording medium having a plurality of information recording areas through the use of holography while moving the recording medium.

Abstract: An object of the present invention is to record and reproduce information through the use of holography, and achieve compact configuration of an optical system with no reduction in the amount of information. For recording, a spatial light modulator (25) generates information light and a phase spatial light modulator (17) generates recording-specific reference light having a spatially modulated phase. The information light and the recording-specific reference light are projected onto one side of an information recording layer (3) of an optical information recording medium (1) coaxially so as to converge on a reflecting surface. At the time of recording of information, P-polarized recording-specific reference light and S-polarized information light are each optically rotated by a two-way split optical rotation plate (21) in directions different between respective half areas of the cross section of the beam thereof.

Abstract: To record information, a recording/reproducing optical system in an optical head irradiates a recording medium with information light and reference light for recording so that two-dimensional image information is recorded on the recording medium by means of interference between the information light and the reference light for recording. To reproduce information, the recording/reproducing optical system irradiates the recording medium with reference light for reproduction, and collects and detects reproduction light occurring from the recording medium. An optical information recording/reproducing apparatus comprises a tilt detector and an image deviation correction circuit. The tilt detector detects a tilt of the recording medium with respect to a predetermined reference position.

Abstract: An object of the invention is to simplify the configuration of an optical system for recording or reproduction without causing a reduction in the amount of information. For recording, a spatial light modulator (27) generates information light by spatially modulating light according to information to be recorded. The information light is collected by an objective lens (21) and applied to an optical information recording medium (1) while converging to become minimum in diameter on the interface between a transparent substrate (2) and a protective layer (5). Recording-specific reference light is collected by an objective lens (31) and applied to the optical information recording medium (1) while converging to become minimum in diameter on the interface between the transparent substrate (2) and the protective layer (5). In an information recording layer (3), the information light and the recording-specific reference light interfere with each other to form an interference pattern.

Abstract: In an optical pickup device in which the response of track follow-up control is improved, a polarizing beam splitter (PBS) combines information light and reference light, and the combined light is made incident on a recording disk via an optical rotary plate divided into two parts, a tracking galvano-mirror, relay lenses, a follow-up galvano-mirror and an objective lens. The tracking galvano-mirror can scan the combined light in a radial direction of the recording disk, and the follow-up galvano-mirror can scan the combined light in a track direction of the recording disk. The objective lens can be moved in opposite directions toward and away from the recording disk by a direct driving type of actuator.

Abstract: A cartridge for storing a holographic recording medium designed to allow a user to check whether a holographic recording medium is contained within the cartridge. The cartridge includes a disc tray on which a recording medium may be mounted and a housing that is capable of accommodating the disc tray and wherein a side surface of the housing may be opened. The housing is constructed to prevent the passage into its interior of light to which the recording medium is sensitive (dead band color). The housing, however, includes at least a portion that allows the passage into its interior of light to which the recording medium is not sensitive (e.g., orange through red colors), to allow the cartridge to be visually checked to determine whether a recording medium is contained within it. To further prevent the passage of any damaging light into the cartridge's interior, an elastic (e.g.

Abstract: In a servo operation, position-controlling light, which is red light, is projected onto a recording medium so as to converge to a minimum diameter on a reflecting surface of the recording medium. In a recording operation, information light and recording-specific reference light, each of which is green light, are projected coaxially onto one side of an information recording layer of the recording medium so as to converge to a minimum diameter at an identical position located off the reflecting surface. Information is recorded in the information recording layer in the form of an interference pattern resulting from interference between the information light yet to impinge on the reflecting surface and the recording-specific reference light reflected by the reflecting surface and an interference pattern resulting from interference between the recording-specific reference light yet to impinge on the reflecting surface and the information light reflected by the reflecting surface.

Abstract: An object of the present invention is to make it possible to record information on an optical information recording medium in the form of three dimensional interference patterns so that the information is erasable in part.

Abstract: An optical information recording device for recording information utilizing holography comprises a recording medium moving means for moving a recording medium, a follow-up control circuit for controlling an irradiation position, and a signal converting means for obtaining a reproduction signal from an address servo-control area including a light source for radiating an information beam and a reference beam onto the recording medium. The follow-up control circuit is composed of a binary-coding means for binary-coding the reproduction signal and a follow-up signal circuit, and detects the travel amount of the irradiation position moving means and generates, according to the travel amount detected and for a specific time during which the irradiation position of the information beam and the reference beam follows, an irradiation position control signal for controlling an irradiation position moving in one information recording area through an output terminal of a gain control amplifier.

Abstract: The present invention makes it possible to reduce the size of an optical system for multiplex recording or reproduction of information utilizing holography.

Abstract: An object of the invention is to provide an optical pick-up device for recording and reproducing information through the use of holography, which can prevent deterioration of recording and reproduction accuracy due to vibrations from exterior or fluctuations in the relative positional relationship with a recording medium.

Abstract: The present invention makes it possible to reduce the size of an optical system for multiplex recording or reproduction of information utilizing holography.

Abstract: The invention makes it possible to form a hologram for reproducing a three-dimensional image easily free of limitations placed by the size of the three-dimensional image to be reproduced, the size of the hologram and reference light for reproduction. A controller calculates a three-dimensional interference pattern for generating reproduction light associated with a desired three-dimensional image when a recording medium (1) is illuminated with reference light for reproduction, divides the three-dimensional interference pattern into partial interference patterns and calculates reference light and information light for recording for each of the partial interference patterns. A final hologram is formed by illuminating the recording medium (1) with reference light and information light for recording using a head (10) while changing the relative positional relationship between the recording medium (1) and the head (10) by moving the head (10) with a VCM (13) while transporting the recording medium (1).

Abstract: When a plurality of magneto-optic disks are inserted via a mail slot provided in a front panel block, a controller controls a manipulator of a robotics block so as to load magneto-optic (MO) disks in MO disk arrays constituted by connecting a plurality of MO drives and one Redundant Array of Inexpensive Disk (RAID) controller. Then, when a RAID recording system is selected by the user, the controller controls the recording operation of the MO disk arrays in accordance with the selected recording system. More specifically, when a RAID recording striping system is selected by the user, the controller divides the data supplied from the outside and controls the recording operation of the MO drives so as to perform the recording in parallel by the MO drives. As a result, data such as image data may be handled with a high transfer speed.