Patent application number | Description | Published |
20080225675 | Optical disk apparatus - An optical disk apparatus includes: a semiconductor laser which emits laser light; a focusing unit which focuses the laser light emitted from the semiconductor laser onto an optical disk; a detector which receives reflected light from the optical disk; a drive unit which rotates the optical disk; and a control unit which controls the semiconductor laser and the drive unit. When the optical disk is reproduced, the control unit causes the semiconductor laser to emit the laser light by a first power realizing a relative intensity noise tolerable for the reproduction of the optical disk. And the control unit causes the drive unit to rotate the optical disk at a first linear velocity which is free from reproduction light deterioration when the semiconductor laser emits the laser light by the first power. | 09-18-2008 |
20080267043 | Optical pickup having optical path length correction function - An optical pickup configured so as to reproduce signals recorded in optical disks of plural standards by means of a single laser beam. The optical pickup has an objective lens for gathering a laser beam emitted from a semiconductor laser—which emits a laser beam of single wavelength—onto a signal recording layer provided in each of optical disks of first and second standards whose cover layers differ from each other in terms of a thicknesses. The first standard is; for example, a CD, and the second standard is; for example, a DVD. An optical path length correction member—in which there is formed an optical path length correction section for making a correction to an optical path length falling within a range smaller than the diameter of a light beam passing through the objective lens—is provided in an optical path between the semiconductor laser and the objective lens. The optical path length correction section may also be formed on a lens plane of the objective lens facing the semiconductor laser. | 10-30-2008 |
20090252022 | Method of Manufacturing Synthetic Resin Lens, Method of Manufacturing Reformed Synthetic Resin Material and Optical Pickup Apparatus - A method of manufacturing a synthetic resin lens, comprising: adjusting a degree of change in transmittance of a lens member made of synthetic resin for a blue violet laser beam with accumulated application of the blue violet laser beam, by applying to the lens member an electromagnetic wave shorter in wavelength than the blue violet laser beam. | 10-08-2009 |
20100238781 | Optical Pickup Apparatus and Objective Lens - An optical pickup apparatus comprising: a laser diode; an objective lens made of synthetic resin arranged in an optical path of laser light between the laser diode and an optical disc so that the laser light from the laser diode is focused onto a signal recording layer through a protection layer of the optical disc; and an aberration correction element interposed in an optical path of the laser light between the laser diode and the objective lens, the aberration correction element configured to be operated so as to correct spherical aberration caused by moisture-absorption characteristics of the objective lens. | 09-23-2010 |
20110103215 | Optical Pickup Apparatus - An optical pickup apparatus, which reads signals recorded on first and second signal recording layers of an optical disc, includes: a laser diode; an objective lens to condense a laser beam to the first and second signal recording layers; and a collimating lens disposed in a light path of the laser beam between the laser diode and the objective lens and configured to correct a spherical aberration by moving in a light axis direction of the laser beam, and the objective lens includes a bifocal lens and is configured such that a second focal point does not coincide in position with the second signal recording layer when a first focal point coincides in position with the first signal recording layer, and the first focal point does not coincide in position with the first signal recording layer when the second focal point coincides in position with the second signal recording layer. | 05-05-2011 |
20110110215 | Optical Pickup Apparatus - An optical pickup apparatus comprises: a first laser diode that generates a first laser beam having a first wavelength; a second laser diode that generates a second laser beam having a second wavelength longer than the wavelength; a third laser diode that generates a third laser beam having a third wavelength longer than the first wavelength and shorter than the second wavelength; an objective lens having an inner, outer, intermediate regions on an incident surface, the first laser beam being condensed on a signal recording layer of a first optical disc by condensing actions of the inner and outer regions, the second laser beam being condensed on a signal recording layer of a second optical disc by condensing actions of the inner and intermediate regions, the third laser beam being condensed on a signal recording layer of a third optical disc by condensing actions of the inner and intermediate regions. | 05-12-2011 |
20110116354 | Optical Pickup Apparatus - An optical pickup apparatus includes: a laser diode configured to emit a laser beam; and an objective lens configured to condense the laser beam into a laser spot through which a signal recorded on a signal recording layer of an optical disc is read out by the laser beam, the objective lens having formed thereon a lens surface with a second numerical aperture for acting as a lens, which is larger than a first numerical aperture for forming the laser spot. | 05-19-2011 |
20110149709 | Optical Pickup Apparatus - An optical-pickup apparatus includes: a three-wavelength-laser diode including first-, second-, and third-laser elements to emit first-, second-, and third laser beams having first, second, and third wavelengths, respectively, the three laser elements housed in the same case; an objective lens to focus the three laser beams onto first- to third-optical-disc-signal-recording layers, respectively; a first photodetector to be irradiated with first-return light reflected from the first-optical-disc-signal-recording layer, a second photodetector to be irradiated with second- and third-return lights respectively reflected from the second- and third-optical-disc-signal-recording layers; a polarizing-beam splitter to reflect the three laser beams toward the lens, and allow the three return lights having passed through the lens to pass therethrough; a semitransparent mirror on which the three return lights having passed through the polarizing-beam splitter are incident, and which guide the first-return light toward the first photodetector and the second- and third-return lights toward the second photodetector. | 06-23-2011 |
20110170396 | LIGHT EMITTING DEVICE, OPTICAL PICKUP APPARATUS AND METHOD FOR MANUFACTURING THE SAME - In the present invention, to improve CD read/write characteristics having poor image height characteristics, a third light emitting source emitting a third laser beam for CD is disposed on an optical axis of an objective lens. Thereby, the third laser beam emitted from the third light emitting source travels along the optical axis of the objective lens, thus generating no coma aberration in the third laser beam. Furthermore, in the present invention, a second light emitting source emitting a second laser beam for DVD and a first light emitting source emitting a first laser beam for BD are disposed across the third light emitting source. Thereby the phase propagation directions of coma aberrations in the first and second laser beams coincide with each other. Adjustment of the coma aberration in one of the laser beams enables the coma aberration in the other laser beam to be adjusted. | 07-14-2011 |
20110182167 | OPTICAL PICKUP DEVICE AND METHOD FOR MANUFACTURING THE SAME - An optical pickup device comprises a first objective lens fixed on a lens holder and configured to focus a first laser beam on a signal recording layer provided in an optical disc, the lens holder supported by support wires so that the lens holder is movable toward a signal surface of an optical disc and in a radial direction of the optical disc, and a second objective lens fixed on the lens holder and configured to focus a second laser beam on a signal recording layer provided in an optical disc. Bearing surfaces of the first and second objective lenses are tilted at predetermined angles, respectively, generation directions of coma aberrations by the first and second objective lenses are broadly divided by a simple method, and the objective lenses are fixed with the directions of the coma aberrations aligned. | 07-28-2011 |
20110191794 | OPTICAL PICKUP APPARATUS - An optical-pickup apparatus includes first and second objective lenses that focus first and second laser light on information-recording layers of first and second optical discs, the second optical disc having an information-recording format different from that of the first optical disc; and a lens holder that integrally holds the first and second objective lenses in an adjacent manner, a disc surface of the first optical disc and of the second optical disc being substantially parallel to confronting faces of the first and second objective lenses, that confront the disc surface, a minimum distance between the disc surface and the confronting faces in a direction of an optical axis of the turntable being greater than a thickness of the turntable in a direction of a rotation axis of the turntable, either one or both of the first and second objective lenses configured to focus bluish-violet laser light on an optical disc. | 08-04-2011 |
20110205878 | LASER ATTACHMENT DEVICE AND OPTICAL PICK-UP DEVICE USING THE SAME - In a laser attachment device of the preferred embodiment of the invention, a pair of protruding portions are formed on a seating surface of a LD holder by which the position of a CAN package is fixed. The CAN package inserted in a through-hole comes into contact with the pair of protruding portions, and then is fixedly bonded to the inside of the LD holder while being inclined with the protruding portions being the starting point of the inclination. This structure allows the luminance adjustment of a laser beam to be performed without causing displacement of the emitting direction of the laser beam from an optical axis of an optical pick-up device. Thus, the laser attachment device having an improved workability and being suitable for mass production is achieved. | 08-25-2011 |
20110209164 | Optical Pickup Apparatus and Manufacturing Method of Optical Pickup Apparatus - An optical-pickup apparatus includes: a first-objective lens; a second-objective lens; a lens holder including a first-lens barrel having the first-objective lens mounted on an end face thereof and a second-lens barrel having the second-objective lens mounted on an end face thereof; an actuator unit having the lens holder mounted thereon; and a housing having the actuator unit mounted thereon, the first and second objective lenses each being mounted on the lens holder such that a direction, in which wavefront of coma aberration on each lens face is most advanced in phase, is aligned with a radial direction of an information-recording medium, the actuator unit being mounted on the housing such that an optical axis of the first-objective lens is inclined in the radial direction at an inclination angle of the axis toward a recording surface of the medium required to cancel coma aberration of the first-objective lens to the surface. | 08-25-2011 |
20110211435 | LASER ATTACHMENT DEVICE AND OPTICAL PICK-UP DEVICE USING THE SAME - A laser attachment device of the present invention is formed of a LD package and a LD holder housing it. A first inner wall of the LD holder to come into contact with a side surface of the LD package is an inclined surface. This allows the facing direction of the LD package to be corrected by the first inner wall being the inclined surface, even when a laser beam emitted from a light emitting chip housed in the LD holder is inclined with respect to an optical axis. Thus, the traveling direction of the laser beam is corrected to the optical axis side. | 09-01-2011 |
20110214137 | LENS HOLDER AND OPTICAL PICKUP APPARATUS USING THE SAME - Provided is a lens holder comprising: a mounting hole into which a condenser lens part of the objective lens is to be inserted; a peripheral part which surrounds the mounting hole and on which a flange part of the objective lens is to be mounted; and three protrusions provided in the peripheral part to be spaced apart from each other and to protrude higher than a main surface of the peripheral part. Also provided is an optical pickup apparatus comprising the lens holder and an objective lens supported with a condenser lens part inserted into the mounting hole of the lens holder, and with the flange part being in contact with the three protrusions. | 09-01-2011 |
20110235494 | Optical Pickup Apparatus - An optical pickup apparatus includes: a laser diode configured to generate a laser beam; and an objective lens having an annular diffraction zone formed on an incident surface thereof on which the laser beam is incident, the annular diffraction zone being a zone configured to focus the laser beam on each of signal recording layers of first to third optical discs so that a signal recorded in each of the signal recording layers of the first to third optical discs are read, the first optical disc having the signal recording layer at a first distance from a surface thereof, the second optical disc having the signal recording layer at a second distance longer than the first distance from a surface thereof, the third optical disc having the signal recording layer at a third distance longer than the first distance and shorter than the second distance from a surface thereof. | 09-29-2011 |
20110249545 | Objective Lens and Optical Pickup Apparatus - An objective lens includes: a diffraction area having a diffraction structure provided thereon concentrically around an optical axis of the objective lens; and a first non-diffraction area provided outward an outer circumference of the diffraction area, the objective lens being configured to focus first laser light on a signal recording surface of a first optical recording medium by refraction in the first non-diffraction area; focus second laser light, different in wavelength from the first laser light, on a signal recording surface of a second optical recording medium by diffraction in the diffraction area; and focus third laser light, different in wavelength from the first laser light and the second laser light, on a signal recording surface of a third optical recording medium by diffraction in the diffraction area. | 10-13-2011 |
20120026859 | Optical Pickup Apparatus - An optical-pickup apparatus includes: a laser diode having a first-laser element, which emits a first-laser beam, and a second-laser element, which emits a second-laser beam having a wavelength shorter than a wavelength of the first-laser beam, arranged in the same package; an objective lens to condense the first- and second-laser beams emitted from the laser diode to signal-recording layers of first- and second-optical discs, respectively, the second-optical disc being of a standard different from a standard of the first-optical disc; and a collimating lens arranged in an optical path between the laser diode and the objective lens, the collimating lens configured to change the first- and second-laser beams from divergent light to parallel light, the collimating lens being inclined with respect to optical axes of the first- and second-laser beams so that astigmatism in the first- and second-laser beams is corrected. | 02-02-2012 |
20120201109 | Optical Pickup Apparatus - An optical-pickup apparatus includes: a diffraction grating that a laser beam enters, the diffraction grating being configured to generate a main beam that is 0th-order light and sub-beams that are +1st-order diffracted light and −1st-order diffracted light; an objective lens to focus the main and sub-beams onto a signal-recording layer; a main-beam light-receiving portion that the main beam reflected by the signal-recording layer is applied to; and sub-beam light-receiving portions that the sub-beams reflected by the signal-recording layer are respectively applied to, each light-receiving area of the sub-beam light-receiving portions being smaller than a light-receiving area of the main-beam light-receiving portion, wherein a focusing-control operation is performed by a differential astigmatic method using the main beam applied to the main-beam light-receiving portion and the sub-beams respectively applied to the sub-beam light-receiving portions. | 08-09-2012 |
20120275289 | LIGHT EMITTING DEVICE, OPTICAL PICKUP APPARATUS AND METHOD FOR MANUFACTURING THE SAME - In the present invention, to improve CD read/write characteristics having poor image height characteristics, a third light emitting source emitting a third laser beam for CD is disposed on an optical axis of an objective lens. Thereby, the third laser beam emitted from the third light emitting source travels along the optical axis of the objective lens, thus generating no coma aberration in the third laser beam. Furthermore, in the present invention, a second light emitting source emitting a second laser beam for DVD and a first light emitting source emitting a first laser beam for BD are disposed across the third light emitting source. Thereby the phase propagation directions of coma aberrations in the first and second laser beams coincide with each other. Adjustment of the coma aberration in one of the laser beams enables the coma aberration in the other laser beam to be adjusted. | 11-01-2012 |