Pioneer Corporation

Pioneer Electronic Corporation

Akihiro Tachibana

Yoshihisa Kubota

Satoshi Sugiura

Satoru Tanaka

Yoshihisa Itoh

Kazuo Kuroda

Masakazu Ogasawara

Shuuichi Yanagisawa

Akira Miura

Toshihiko Kurihara

Michikazu Hashimoto

Yoshiyuki Tsukai

Yuzo Yamakawa

Michio Sakano

A holographic recording and reproducing apparatus comprises: a pickup for moving an objective lens that focuses a coherent light beam along a recording track on a holographic recording medium and for detecting reflected light from the recording track to perform focus- and tracking-servo control; a relative velocity determination unit for determining a relative velocity of a converging position of the objective lens with respect to the holographic recording medium; a driving unit for changing a relative position of the objective lens with respect to an optical path of the coherent light beam so as to make the relative velocity fall within a predetermined range at least during a predetermined period; and a control unit for performing recording or reproduction for a recording layer during the predetermined period. The holographic recording medium includes a plurality of markers used for positioning an optical interference pattern of the coherent light beam.

Holographic recording/reproducing apparatus having relative speed controller and method

A recording medium has a recording layer capable of be performed in recording or reproducing of information with light irradiation and carried with a substrate. The recording medium includes a guide layer having guide tracks each followed by a light beam spot focused from an objective lens through the recording layer, the guide tracks disposed at a first pitch. The recording medium includes a guide track transfer region provided on the guide layer and having at least one line of a track arranged in parallel between the guide tracks adjacent to each other in the extending direction of the guide track so as to be in a direction perpendicular to the guide track within a range shorter than that of the guide track.

Optical recording medium having a plurality of guide tracks transfer regions

A hologram recording apparatus () includes a record angle change device () capable of relatively changing the record angle of a hologram recording medium () relative to signal light (L) and reference light (L); and a control device (). The control device sets a record angle for recording a specific angle record plane as a standard record angle among a plurality of angle record planes on the hologram recording medium. Furthermore, the control device controls the record angle change device so as to change and fix the record angle after then by a predetermined angle from the set standard record angle.

Angle-multiplexing hologram recording device, method, hologram reproduction device, and method

A hologram record apparatus () includes a parameter set device (), a move device (), and a control device (). The parameter set device () modifies parameters for multiple recordings such as a record angle and a focal depth in relation to at least one of signal light (L) and reference light (L) and can fix the parameters. The move device () relatively moves the focus position of the signal light and the reference light in the direction along the record surface of a hologram record medium. The control device () performs control so that the parameter for the last recording used for recording at the m-th focus position is used as the parameter for the first recording at the m+1-th focus position.

Multiplex recording type hologram recording device, method, hologram reproduction device, and method

A spatial light modulator, in which light modulation elements are arranged in a same plane. In the spatial light modulator, a plurality of the light modulation elements are arranged such that there are at least two periods of periodic structure corresponding to an arrangement of the light modulation elements in an arbitrary direction in the plane where the light modulation elements are arranged.

Spatial optical modulator

An example recording apparatus includes a pulse oscillation laser, a half mirror for splitting the pulse oscillation light of the laser into a signal light and a reference light, an optical shutter disposed in the optical path of the signal light, a beam expander for converting the signal light into a light beam of a predetermined diameter, a spatial modulator for modulating the recording data into two-dimensional image information, a Fourier Transform lens for introducing the signal light modulated by the spatial modulator onto a recording medium, mirrors for introducing the reference light onto the recording medium with a predetermined angle, a system control unit, a laser driver, a system controller, a recording medium drive mechanism, a modulator driver, a data input unit, and a data processing unit.

Recording device, reproduction device, and recording/reproduction device

A hologram record apparatus () includes a spatial light modulator () and a control device (). The spatial light modulator () is arranged on an optical path of signal light (L) and divided into a plurality of cell blocks () arranged in a matrix. Each of the cell blocks () is further divided into a plurality of cells () arranged in a matrix. The spatial light modulator () can perform modulation on the cell basis. The control device () controls the spatial light modulator so as to modulate the signal light according to a plurality of record information sets to be recorded on a hologram record medium (). Pluralities of modulation units () existing in the same cell block are not made into identical patterns. Since a plurality of cell blocks having a large pitch as compared to the pixel pitch are simultaneously or successively turned on/off, it is possible to reduce the distance between the zeroth-order light and the higher-order light.

Hologram recording device and hologram reproduction device

A hologram recording medium is a hologram recording medium which is irradiated with light for recording information therein or reproducing information therefrom. The hologram recording medium has a recording layer made of a photo-sensitive material capable of preserving an optical interference pattern, a reflective layer disposed on one side of the recording layer opposite to the side on which an light beam impinges, and a quarter wavelength plate interposed between the recording layer and the reflective layer.

Hologram recording medium and recording and reproducing system

A hologram recording and reproducing system having compatibility has: a supporting unit for freely attachably supporting a recording medium including a photosensitive material; a signal light-generating unit for projecting a coherent light beam modulated according to a predetermined data into a recording medium and generating a diffraction grating by providing a three-dimensional light interference pattern in the recording medium; a detector unit for detecting and photoelectrically converting a diffracted light from the diffraction grating; and a demodulating unit for demodulating a predetermined data from an output from the detector unit. The detector unit has an intermediate data-generating unit for generating an intermediate data, and the demodulating unit has a conversion table in which the intermediate data and the predetermined data are uniquely associated, and demodulates the predetermined data by performing a computation based on a correlation in the conversion table.

Hologram recording/reproducing system

A hologram apparatus includes a light beam interfering section for allowing reference and signal light beams to interfere to form a hologram recording region; a reproducing section for allowing the reference light beam to be incident on the recording region and generating a reproduced light; an image sensor for detecting a hologram-reproduced image; a distortion determining section for detecting the distortion-detecting data from the hologram-reproduced image to determine a distortion of the hologram-reproduced image; a distortion corrector for correcting a distortion of the hologram-reproduced image; and a controller for correcting the distortion in accordance with a determined distortion.

Hologram apparatus capable of detecting and correcting distortion of hologram image

In an optical recording medium having a super-resolution layer structure using near-field light, comprising a readout layerfor forming a light scattering regionin the center portion of a laser spot, and a recording layerfor receiving near-field lightgenerated from the light scattering regionof the readout layer, scattering bodiesfor increasing the generated near-field light are provided while enhancing a scattering effect of the near-field lightapplied to a markof the recording layer

Optical recording medium using scattering bodies to enhance modulation

An optical pickup device includes a photodetector divided into four light-receiving elements by two dividing lines, an incident optical system for irradiating a light beam onto an optical recording medium, and a receiving optical system for guiding a return light from the optical recording medium to the photodetector, wherein the receiving optical system includes astigmatism generating means for generating astigmatism having an astigmatism axis at an angle of 45 degree with respect to the two dividing lines.

Astigmatism generating device to remove comma aberration and spherical aberration

An optical pickup apparatus which can be designed compact while having a plurality of semiconductor lasers. The optical pickup apparatus, which reads recorded information from an optical recording medium, comprises an optical system including light intensity detection element having a quarter-split light receiving surface, two semiconductor lasers for emitting light beams of different wavelengths, an objective lens for directing each of the light beams onto an optical recording medium to form a light spot on a recording surface, and a holographic optical element located between the quarter-split light receiving surface and the objective lens, whereby the holographic optical element eliminates coma aberration and spherical aberration of light beams launched from the two semiconductor lasers and traveled through the recording surface and the objective lens, thereby generating a predetermined amount of astigmatism. The holographic optical element further has a lens performance for converging light beams, launched from the two semiconductor lasers and traveled through the recording surface and the objective lens, onto the quarter-split light receiving surface.

Optical pickup apparatus

An optical pickup apparatus which can be designed compact while having a plurality of semiconductor lasers. The optical pickup apparatus, which reads recorded information from an optical recording medium, comprises an optical system including light intensity detection means having a quarter-split light receiving surface, two semiconductor lasers for emitting light beams of different wavelengths, an objective lens for directing each of the light beams onto an optical recording medium to form a light spot on a recording surface, and first and second holographic optical elements located between the quarter-split light receiving surface and the objective lens, whereby the first holographic optical element eliminates coma aberration and spherical aberration of a light beam of a first wavelength from one of the semiconductor lasers, traveled through the recording surface, thereby generating a predetermined amount of astigmatism, and the second holographic optical element eliminates coma aberration and spherical aberration of a light beam of a second wavelength from the other one of the semiconductor lasers, traveled through the recording surface, thereby generating a predetermined amount of astigmatism.

An optical pickup device includes at least four light-receiving-surface elements, at least two semiconductor lasers, and an optical system for irradiating a light beam onto an optical recording medium through an objective lens for forming a light spot onto an information recording surface thereof. The optical system guides the return light from the light spot to the four light-receiving-surface elements through the objective. The semiconductor lasers are mounted on a plurality of flat side surfaces of a single heat sink which do not exist on a common virtual plane.

Growing community of inventors

Tsurugashima, Japan

Akihiro Tachibana