Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Makoto Takashima

Hideki Aikoh

Hiroyuki Nakamura

Tohru Nakamura

Kousei Sano

Hideki Nakata

Hironori Tomita

Joji Anzai

Takao Hayashi

Eishin Mori

Akira Yoshikawa

Tomio Yamamoto

Toru Tanaka

Kouretsu Boku

Tadashi Kuroda

Kenichi Shinotani

An object of the invention is to provide an optical element for use in an optical information recording and reproducing device or a like device for recording or reproducing information with respect to an information recording medium using laser light, wherein the optical element is a resin optical element capable of suppressing lowering in transmittance due to deterioration by irradiation of light having a high energy density, and maintaining a high transmittance for a long time. To realize the above object, used is an optical element made of a silicon resin cured material obtained by subjecting a silicon resin composition containing a silsesquioxane compound to a curing treatment.

Optical head, optical information recording and reproducing device, and optical information system device

An optical disk device of the present application includes: a turntableincluding plural induction groovestoas concave portions radially extending from vicinity of a center of the turntableand having open portions in an outer periphery of the turntableand plural through-holestopenetrating bottom facestoon the vicinity of the center side of the plural induction groovestoand a top face of the turntable; and an outer rotor type spindle motorprovided with plural finstoas convex portions on a rotor on a side face thereof. The optical disk device of the present application utilizes an airflow generated by rotation of the rotor of the spindle motorand the turntablein conjunction therewith as a dust removing wind for removing dust attaching to an objective lens side area.

Optical disc device and method for controlling optical disc device

An optical-disk drive device is provided which is capable of executing recording or reproduction at a plurality of numerical apertures and keeping constant the quantity of light which is emitted by a light-emitting element. This optical-disk drive device includes: light-emitting elements; a beam splitter which allows a luminous flux that is emitted by each of these light-emitting elements to branch off to a first luminous flux and a second luminous flux; a photo-detector which detects a front light that has branched off at the beam splitter; an aperture restriction member; and a controller which controls the quantity of light that is emitted by each of the light-emitting elements, using a signal which is obtained by the photo-detector, in which the photo-detector has a circular first detection area in which an inner luminous flux of the first luminous flux is received, and a ring-shaped second detection area in which an outer luminous flux of the first luminous flux is received; and the controller controls the quantity of light, at the time of a large numerical aperture, based on the quantity of light which is received in the first detection area and the second detection area, and controls the quantity of light, at the time of a small numerical aperture, based on the quantity of light which is received in the first detection area.

Apparatus for switching modes based on quantity of light received in first section of a photodetector section and first plus second section for controlling a laser diode output

An optical head including a light source for emitting luminous energy recordable on a recording medium, a heat radiating section, in contact with the light source, for radiating heat which accompanies the light emission thereof, and a resin-made bench for mounting and fixing the aforementioned elements, or an optical head having a light source for generating luminous energy required for recording on a disk-shaped information recording medium or reproducing information recorded on the disk-shaped information recording medium; a radiator plate, in contact with the light source either directly or indirectly, for guiding heat which accompanies the emission of light by the light source; an objective lens for focusing light on the disk-shaped information recording medium; an objective lens drive unit for driving the objective lens in the focal and radial direction of the medium; a light receiving element for receiving light reflected from the medium; a sheet-shaped flexible circuit for feeding power to the light source and the light receiving element and communicating signals from the light receiving element; and an optical bench holding at least the light source, the objective lens drive unit, the radiator plate and the light receiving element, in which the radiator plate is brought into contact with a heat transfer section provided in the flexible circuit and, by causing the flexible circuit to guide heat from the radiator plate, heat generated by the light source is radiated through the flexible circuit and the radiator plate.

Optical head and optical head feeder

An optical head includes: a light source for emitting light; first optical element for forming at least three light beams from the light emitted from the light source; second optical element for converging said at least three beams on a storage medium; and a photodetector for receiving said at least three beams reflected by the storage medium to generate electrical outputs in accordance with an intensity of the light beams, the photodetector including; a semiconductor substrate; a light receiving section formed on a surface of the semiconductor substrate for receiving the light beams reflected by the storage medium; a plurality of input terminals for receiving a supply of a predetermined potential; and a plurality of output terminals for outputting electric signals, wherein the light receiving section includes a plurality of light receiving elements for signal detection provided apart from each other on the surface of the semiconductor substrate and a plurality of stray light carrier absorption regions provided so as to substantially fill regions between the plurality of light receiving elements for signal detection, and wherein the plurality of stray light carrier absorption regions are made of first impurity diffusion regions of a first-conductivity type formed in the semiconductor substrate, the first impurity diffusion regions forming PN junctions and depletion layers in the semiconductor substrate so as to absorb stray light carriers generated in the semiconductor substrate by stray light.

Optical detector having stray carrier absorption regions between light

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Nara, Japan

Makoto Takashima