Pioneer Electronic Corporation

Pioneer Corporation

Fumihiko Sano

Naoharu Yanagawa

Shinji Suzuki

Masanori Nakahara

Hiroshi Suzuki

Yasumitsu Suzuki

Susumu Nomura

A sufficient S/N ratio in reproduction of an optical disk is achieved without complexing a circuit structure even if a data recording speed relative to the optical disk is increased. When data is recorded into an optical disk (DK), in an information recording and reproduction device (RP), both a first light beam and a second light beam are emitted at the same time. A sub-actuator section () is provided in addition to a main actuator () for correcting the displacement of light collecting spots caused by the displacement between the optical axis of the first beam and the optical axis of the second beam. Only the optical axis of the second light beam is adjusted by the sub-actuator section ().

Optical pickup device, and information recording and reproduction device

A laser light intensity controller includes a polarizing beam splitter for passing most of one of an x-direction polarization component perpendicular to a direction in which a laser beam emitted from a light source travels and a y-direction polarization component parallel with the traveling direction and for reflecting a little portion of the one polarization component as monitoring light, and a photodetector for receiving the reflected monitoring light to generate a light intensity signal. The controller drives the light source in accordance with the light intensity signal. The photodetector reflects the other of the x-direction polarization component and the y-direction polarization component and is not sensitive thereto, and absorbs the one polarization component and is sensitive thereto.

Laser light intensity controller

A laser light intensity controller includes a polarizing beam splitter for passing most of one of an x-direction polarization component perpendicular to a direction in which a laser beam emitted from a light source travels and a y-direction polarization component parallel with the traveling direction and for reflecting a little portion of the one polarization component as monitoring light, and a photodetector for receiving the reflected monitoring light to generate a light intensity signal. The controller drives the light source in accordance with the light intensity signal. An optical element which passes passing only the one polarization component is installed between the light source and the polarizing beam splitter.

An optical record medium has an information record surface on which a plurality of circular arc tracks are arranged such that centers of the circular arc tracks are arranged in a straight line direction. An apparatus for optically recording and reproducing information onto and from the optical record medium is provided with: a rotatable optical system for emitting a light beam onto the circular arc track of the optical record medium which is being moved straight in the straight line direction, while being rotated with an rotational axis perpendicular to the information record surface; a straight moving device for relatively moving the rotatable optical system and the optical record medium to each other in the straight line direction; a detecting device for detecting a displacement amount from the circular arc track at an irradiated position on the information record surface of the light beam, on the basis of a reflection light from the circular arc track of the light beam, and outputting a displacement amount signal indicating the detected displacement amount; a perpendicularly moving device for relatively moving the optical record medium and the rotatable optical system to each other perpendicularly to the straight line direction such that the irradiated position approaches the circular arc track, on the basis of the outputted displacement amount signal; and a recording and reproducing device for recording and reproducing the information onto and from the optical record medium by use of the light beam emitted to the circular arc track.

Optical information recording and reproducing apparatus

An optical head emits a plurality of light beams onto an information record medium to perform a recording operation and/or a reproducing operation. The optical head is provided with: a plurality of light source, each outputting one of the light beams; an objective lens for collecting the light beams outputted from the light sources onto the information record medium; an optical element located on the optical path of only one of the light beams; a detector for receiving the light beam from the information record medium and outputting a detection signal; and a generating circuit for generating a drive signal based on the detection signal. The optical head is further provided with a dual-axis actuator for actuating the optical element in an optical axis direction of the light beam and in a substantially perpendicular direction to the optical axis direction in accordance with the drive signal. Because the objective lens is commonly used for all of the light beams while the optical element is actuated by the dual-axis actuator, the number of parts in the optical head is reduced while permitting the necessary collection of the light beams from the information record medium.

Optical head

A rotary type pickup apparatus adopting a light modulation system, is capable of over-writing and suitable for miniaturization. In the optical pickup apparatus constituted by a stationary optical part and a rotary optical part which comprises an objective lens and a light beam guiding device, a recording magnet and an initialization auxiliary magnet are provided in the rotary optical part, the recording magnet being disposed close to the objective lens and the initialization auxiliary magnet being positioned over a rotation circumference where the objective lens rotates. Further provided are a recording magnet and an initialization auxiliary magnet which are disposed so as to pinch a magnetooptical recording medium together with the objective lens, the initialization auxiliary magnet being positioned behind the recording magnet in a sending direction of an optical card.

Magneto-optical card recording apparatus employing an initialization

An optical pickup device includes: a stationary optical system for emitting a light beam and for producing a tracking error signal; and a rotary optical system rotatable around a rotary axis. The rotary optical system includes: a dividing unit for dividing the light beam emitted from the stationary optical system into a main beam and sub-beams; an objective lens for converging the main beam and the sub-beams on a recording surface of an optical tape and for receiving the main beam and the sub-beams reflected by the recording surface; and a guiding unit for guiding the main beam and the sub-beams to the objective lens and for guiding the main beam and the sub-beams reflected by the recording surface to the stationary optical system. The dividing unit, the objective lens and the guiding unit are arranged so as to be integrally rotated along with the rotary optical system, and the dividing unit is arranged on an optical path of the light beam between the stationary optical system and the objective lens.

Rotary optical system for guiding and converging divided light beams to

An optical pickup includes: a laser diode for emitting p-polarized light, the laser diode having unit for controlling output power of the p-polarized light by detecting power of the emitted light in front thereof; a photodetector for receiving a laser light and outputting a signal corresponding to quantity of the laser light received; a polarization prism for transmitting and guiding the emitted light to an optical disc on which information is recorded by applying heat thereon, and for reflecting and guiding at least a portion of the light reflected by the optical disc to the photodetector. The optical pickup substantially satisfies the following conditions:

Growing community of inventors

Tokorozawa, Japan

Fumihiko Sano