Pioneer Corporation

Pioneer Electronic Corporation

Masayuki Koyama

Shinichi Takahashi

Akira Miura

Ko Ishii

Makoto Kawamura

Mitsutoshi Sugano

Hirokatsu Nagatake

Aki Yoshioka

Yuichi Mizuuchi

Tsuyoshi Iwano

Masaya Murata

Takehiko Hayashi

Taichi Akiba

Hitoshi Furuhata

Shigeyuki Sasanuma

Tomotaka Nishimura

Osamu Ueda

A laser light source () and a heat-radiating plate () are provided on a pickup base (). The laser light source () irradiates a laser beam to an optical disk (). The heat-radiating plate () has at least one part exposed outside the pickup base (), having a predetermined distance between the heat-radiating plate () and the pickup base (), and radiates heat generated by the laser light source (). The plate () can radiate heat also from a surface opposing the pickup base () and can therefore have a high heat-radiating efficiency.

Pickup device with heat-radiating mechanism

A communication hole () is provided in a pickup base (). A laser light source () is provided at an end of the communication hole (). A grating () is provided at another end of the communication hole (). The communication hole () is provided with a heat radiation path () which connects the inside of the communication hole () with the outside of the pickup base (). Heat generated from the laser light source () is radiated from the heat radiation path ().

Pickup device having a heat-radiation path

An optical pickup apparatus and a laser diode chip which can simplify and miniaturize a construction of the apparatus is provided for using a plurality of laser beams of different wavelengths. The laser diode chip is a chip for the optical pickup apparatus in which a plurality of light emitting portions for emitting the laser beams of the different wavelengths in the same emitting direction are formed on a substrate. Light emitting points of the plurality of light emitting portions are located at positions which are different in the emitting direction.

Optical pickup apparatus and laser diode chip

An optical pickup apparatus comprises a first light source for emitting a first laser beam having a first wavelength; a second light source for emitting a second laser beam having a second wavelength; and an objective lens for condensing the first laser beam and the second laser beam. The first light source and the second light source are disposed in positions in such a way that a total amount of coma aberration, which is generated on the first laser beam in accordance with a distance between the first light source and an optical axis of a whole optical system and coma aberration, which is generated on the first laser beam in accordance with a tilting amount of the objective lens becomes null, and a total amount of coma aberration, which is generated on the second laser beam in accordance with a distance between the second light source and said optical axis and coma aberration, which is generated on the second laser beam in accordance with the tilting amount of the objective lens becomes null.

Optical pickup apparatus

An optical pickup apparatus which supports two wavelengths and is amenable to a reduction in size without employing a combining prism. The optical pickup apparatus employs a semiconductor laser device implemented in the form of a one-chip laser diode having two light sources for emitting a first laser beam and a second laser beam at a wavelength different from that of the first laser beam. A photodetector unit has a first detector section for receiving the first laser beam and a second detector section for receiving the second laser beam, and is set at positions at which the first and second laser beams follow return light paths of different lengths from an optical disc to the first and second detector sections.

Optical pickup apparatus for reading different types of recording media at different reading wavelengths

An optical pickup apparatus capable of reading information from recording media of different read wavelengths, includes a light-emitter having a first light source for emitting a first laser beam integrated with a second light source for emitting a second laser beam of a different wavelength from that of the first laser beam. The optical pickup apparatus includes a photodetector for receiving a beam reflected by each of the recording media and an optical system having a plurality of optical elements which form an optical path to guide the first and second laser beams to the recording media and which form an optical path for guiding the reflected beam to the photodetector and through which the first and second laser beams pass.

An optical pickup apparatus includes a semiconductor laser device having a plurality of light emitting portions for emitting laser beams having different wavelengths on a substrate for emitting a laser beam from one of the plurality of light emitting portions in response to a light emitter selecting instruction in the same emitting direction. The laser beam emitted from the semiconductor laser device is converged by an objective lens and led to a recording surface of an optical disk, and the objective lens is moved to one of a plurality of different positions in a radial direction of the optical disk, corresponding to the selected light emitting portion.

A two-focal-point pickup device capable of suppressing the generation of glitch or bump in reproduced signal. The optical pickup device irradiates a light beam emitted from a light source onto an optical recording medium to form a light spot on a track of a recording surface of the optical recording medium to read the optical recording medium while controlling the position of the light spot relative to the track of the recording surface. The optical pickup device includes a converging lens section coaxially disposed in an optical axis of the light beam to converge the light beam onto the recording surface; and a hologram lens section coaxially disposed in the optical axis of the light beam to diffract the light beam. The hologram lens section has a diffraction grating pattern being formed in such a manner that a first-order diffraction light of the light beam caused by the hologram lens section and converged on the recording surface has a first numerical aperture existing in a direction intersecting the track extending direction and a second numerical aperture existing in the track extending direction. The first numerical aperture is less than the second numerical aperture. The hologram lens section has a diffraction grating pattern including a parallel-line diffraction grating pattern and two semicircular diffraction grating patterns.

Optical pickup device including a hologram lens section with an oval diffraction grating pattern

A two-focal-point pickup device capable of suppressing the generation of glitch or bump in reproduced signal. The optical pickup device irradiates a light beam emitted from a light source onto an optical recording medium to form a light spot on a track of a recording surface of the optical recording medium to read the optical recording medium while controlling the position of the light spot relative to the track of the recording surface. The optical pickup device includes a converging lens section coaxially disposed in an optical axis of the light beam to converge the light beam onto the recording surface; and a hologram lens section coaxially disposed in the optical axis of the light beam to diffract the light beam. The hologram lens section has a diffraction grating pattern being formed in such a manner that a first-order diffraction light of the light beam caused by the hologram lens section and converged on the recording surface has a first numerical aperture existing in a direction intersecting the track extending direction and a second numerical aperture existing in the track extending direction. The first numerical aperture is less than the second numerical aperture. The hologram lens section has a diffraction grating pattern which is a double side cut circular diffraction grating pattern formed by eliminating two symmetrical portions with the optical axis from a circular diffraction grating pattern. The hologram lens section has a diffraction grating pattern which is a double side cut circular diffraction grating pattern formed by eliminating two symmetrical portions with the optical axis from a circular diffraction grating pattern.

Optical pickup device including a holographic lens section with a double

A two-focal-point pickup device capable of suppressing the generation of glitch or bump in reproduced signal. The optical pickup device irradiates a light beam emitted from a light source onto an optical recording medium to form a light spot on a track of a recording surface of the optical recording medium to read the optical recording medium while controlling the position of the light spot relative to the track of the recording surface. The optical pickup device includes a converging lens section coaxially disposed in an optical axis of the light beam to converge the light beam onto the recording surface; and a hologram lens section coaxially disposed in the optical axis of the light beam to diffract the light beam. The hologram lens section has a diffraction grating pattern being formed in such a manner that a first-order diffraction light of the light beam caused by the hologram lens section and converged on the recording surface has a first numerical aperture existing in a direction intersecting the track extending direction and a second numerical aperture existing in the track extending direction. The first numerical aperture is less than the second numerical aperture.

Optical pickup device including a hologram lens section with an

An optical pickup unit that is capable of reproducing information from two types of recording media whose thickness characteristics differ from each other and can reduce heat generated due to DC offsets generated in a focus actuator, that can suppress a change of an aberration of an objective lens due to the generated heat, and that can suppress a change of its pickup performance includes an objective lens; a lens holder for holding the objective lens; a supporting member for supporting the lens holder; an error signal generator for generating a focus error signal based on the reflected light of the light beam from the recording surface upon which the light beam is being impinged; and a focus controller for actuating and controlling the objective lens such that the light beam is converged on the information recording surface based the error signal; the supporting member supporting the lens holder such that a dead-load suspension position of the lens holder is positioned at a position where an absolute value of an offset component of the error signal obtained in controlling the focus for the first recording medium is equal to an absolute value of an offset component of the error signal obtained in controlling the focus for the second recording medium.

Optical pickup unit capable of reading signals recorded on different

A holder is suspended on a carriage, and a magnetic circuit is disposed adjacent to the holder. The magnetic circuit has a first magnetic pole and a second magnetic pole. A focus coil having a magnetic flux receiving portion is provided around a vertical axis of the holder. A tacking coil having a magnetic flux receiving portion is provided around a horizontal axis of the holder. Both the magnetic flux receiving portions are disposed so as not to be overlapped with each other, and disposed in parallel with one of the surface of the first and second magnetic poles. Both of the magnetic flux receiving portions are flush with each other.

Growing community of inventors

Tokorozawa, Japan

Masayuki Koyama