| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 369112050 | In radiation beam path to storage medium | 46 |
| 20080232224 | OPTICAL PICKUP AND OPTICAL DISC DEVICE - In the present invention, by utilizing the difference between the polarization directions of an optical beam and a reflected optical beam, a neutral density filter part of a variable filter in an optical pickup reduces the light amount of the optical beam and directs the optical beam to the objective lens, and directs the reflected optical beam to a photodetector being a photodetection unit with slight change in the light amount of the reflected optical beam. When reducing a transmitted beam, which is the optical beam transmitted by diffracting the optical beam using a diffraction grating, the irradiation positions of first-order optical beams being diffracted±first-order optical beams on the recording layer of an optical disc are dispersed. | 09-25-2008 |
| 20080239926 | Optical Compensator, Optical Element, Optical Scanning Head An Optical Scanning Device - An optical compensator for use in an optical scanning device for scanning a first optical record carrier ( | 10-02-2008 |
| 20080253263 | Optical head device and diffractive element, optical information apparatus, computer, disc player, car navigation system, optical disc recorder, and vehicle - In an optical head device responding to optical disc of different track pitches, an effect of both obtaining the tracking error signal by the optimum DPP method using a single diffractive element and suppressing the lowering amount in the amplitude of the tracking error signal in a state the object lens is moved by track following is obtained. In the optical head device, the grating phase of left and right regions of a sub-beam generating diffractive element differ from each other by 180 degrees. A central region of the sub-beam generating diffractive element has a grating pattern different from the left and right regions, and is divided into a plurality of regions to form different gratings different from each other. | 10-16-2008 |
| 20080259767 | Objective optical element and optical pickup apparatus - An objective optical element of an optical pickup apparatus has a magnification m | 10-23-2008 |
| 20080285420 | Optical Pickup and Optical Drive - An optical pickup including a two-wavelength multilaser for generating a tracking error signal and a focusing error signal with high accuracy without light quantity variations which otherwise might be caused by the interference. An optical beam of first wavelength is emitted from first laser light source, and an optical beam of second wavelength longer than the first wavelength is emitted from second laser light source. The optical beams of the first and second wavelength are each split into at least one main optical beam and two sub-optical beams by a grating having, in a single plane, a first grating pattern area for splitting the optical beam of the first wavelength and a second grating pattern area for splitting the optical beam of the second wavelength. The area of the first grating pattern area is larger than the area of the second grating pattern area. | 11-20-2008 |
| 20080310283 | Method of Reading Out Information from a Multiple Layer Optical Recording Medium and Optical Readout Device - The present invention relates to a method of reading out information from a multiple layer optical recording medium ( | 12-18-2008 |
| 20080316900 | Optical pickup apparatus, recording/reproducing apparatus provided with the optical pickup apparatus, optical element, and information recording/reproducing method - An optical pickup apparatus for reproducing information from an optical information recording medium or for recording information onto an optical information recording medium, is provided with a first light source for emitting first light flux having a first wavelength; a second light source for emitting second light flux having a second wavelength, the first wavelength being different from the second wavelength; a converging optical system having an optical axis and a diffractive portion, and a photo detector; wherein in case that the first light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the first light flux is greater than that of any other ordered diffracted ray of the first light flux, and in case that the second light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the second light flux is greater than that of any other ordered diffracted ray of the second light flux, where n stands for an integer other than zero. | 12-25-2008 |
| 20090086609 | OPTICAL PICKUP APPARATUS AND DRIVE APPARATUS HAVING THE SAME - An optical pickup apparatus and a drive apparatus having the same are provided. Second light-receiving elements or third light-receiving elements for receiving ±first-order diffraction light beams from a polarization hologram are arranged outwardly of a circular region having the optical axis of a zero-order diffraction light beam on a light detector as its center, a radius of which is expressed by (2×t/n)×(f | 04-02-2009 |
| 20090190459 | Chromatic diffractive optical element corrector, optical system including the same and associated methods - An optical element may include a substrate including a diffractive structure having multiple periods, at least one period of the multiple periods having multiple steps, heights of the multiple steps non-monotonically increasing across the at least one period. The optical element may be used with at least two wavelengths, e.g., three wavelengths, may be on a single surface and may provide an efficiency of at least 50% for all wavelengths. | 07-30-2009 |
| 20100020671 | PHASE CORRECTION ELEMENT AND OPTICAL HEAD DEVICE - The present invention provides a phase correction element which can be used for recording and/or reproducing an information of three types of optical disks for HD, DVD and CD by employing a single objective lens for HD, and an optical head device. | 01-28-2010 |
| 20100103798 | OPTICAL DATA RECORDING AND IMAGING ON MEDIA USING APOCHROMATIC LENSES AND A LIGHT SEPARATING MEANS - An apparatus includes a recording medium ( | 04-29-2010 |
| 20100157777 | OPTICAL HEAD AND OPTICAL DISC DEVICE - A compact and inexpensive optical head that enables stable compatible playback and compatible recording with optical discs of different kinds with the use of a single objective lens is achieved. The order of diffracted light at which the diffraction efficiency by a diffraction element forming the objective lens becomes the maximum is set to the third order for blue light, the second order for red light, and the second order for infrared light in the inner peripheral portion of the diffraction element, and to the sixth order for blue light, the fourth order for red light, and the third order for infrared light to limit the aperture for infrared light in the intermediate peripheral portion. In the outer peripheral portion, the aperture for red light is limited by setting the order to an integer other than multiples of 3 for blue light. | 06-24-2010 |
| 20110075543 | OBJECT LENS, OPTICAL PICKUP, AND OPTICAL DISC DEVICE - An optical pickup includes: a first emitting unit to emit an optical beam of a first wavelength; a second emitting unit to emit an optical beam of a second wavelength; a third emitting unit to emit an optical beam of a third wavelength; an object lens to condense optical beams emitted from the first through third emitting units onto a signal recording face of an optical disc; and a diffraction unit provided on one face of an optical element or the object lens positioned on the optical path of the optical beams of the first through third wavelengths; wherein the diffraction unit includes a generally circular first diffraction region provided on the innermost perimeter, a ring zone shaped second diffraction region provided on the outer side of the first diffraction region, and a ring zone shaped third diffraction region provided on the outer side of the second diffraction region. | 03-31-2011 |
| 20110211438 | COLLIMATING LENS UNIT AND OPTICAL PICKUP DEVICE USING THE SAME - An optical pickup device that can reduce interlayer crosstalk, without changing the configuration of the optical system, and without excessively increasing the size of the optical system. The optical pickup device reproduces a signal from a multilayered optical information recording medium having a plurality of information recording layers. The optical pickup device uses a collimating lens unit as a collimating optical system that collimates light from a light source, and the collimating lens unit includes a first and second lens group arranged at a predetermined distance from each other so as to form a converged light spot in the interior of the collimating lens unit, and an optical element provided between the first lens group and the second lens group so as to form a light spot at a position defocused from the position of the converged light spot, thereby decreasing quantity of light passing through the collimating lens unit. | 09-01-2011 |
| 20120002533 | OPTICAL PICKUP DEVICE - A spectral element separates first laser light in such a manner that an area including only signal light as reflected first laser light is formed on a photodetector. The photodetector is provided with a first sensor group which is disposed at an irradiation position of signal light of the separated first laser light, and a second sensor group which receives zero-th order diffraction light of a main beam and two sub beams of second laser light that has been transmitted through the spectral element. The second sensor group includes a four-divided sensor which receives the main beam. The four-divided sensor is disposed in an area surrounded by the first sensor group. Zero-th order diffraction light of the first laser light that has been transmitted through the spectral element is irradiated onto the four-divided sensor. | 01-05-2012 |
| 20120075979 | OPTICAL ELEMENT AND OBJECTIVE LENS THROUGH WHICH A PLURALITY OF LIGHT BEAMS HAVING DIFFERENT DESIGN WAVELENGTHS PASS - A method of designing an optical element to be used for an optical system in which each of a plurality of light beams having different design wavelengths passes through the optical element is provided. The method includes determining at least two types of optical path difference functions including first and second optical path difference functions in such a manner that proportion, brought by the first optical path difference function, between diffraction orders at which diffraction efficiencies of the plurality of light beams are maximized is different from proportion, brought by the second optical path difference function, between diffraction orders at which diffraction efficiencies of the plurality of light beams are maximized, and obtaining a shape defined by combining the at least two types of optical path difference functions so as to apply the obtained shape to at least one surface of surfaces of the optical element. | 03-29-2012 |
| 20120106311 | COMPATIBLE OPTICAL PICKUP AND OPTICAL INFORMATION STORAGE MEDIUM APPARATUS USING THE SAME - An optical pickup and an information storage medium system using the same. The optical pickup includes a light source that emits light having a plurality of different wavelengths. The optical pickup includes a diffraction device having a plurality of diffraction patterns corresponding to the plurality of different wavelengths to divide the light incident from the light source unit into main light and sub light. The optical pickup further includes a photo-detector having a first main light reception unit that receives the main light and a first sub light reception unit that receives the sub light so as to detect an information signal and/or an error signal by receiving reflected light. The first sub light reception unit of the photo-detector is shaped so as to reduce reception of noise sub light due to diffraction based on an undesired diffraction pattern of sub light generated the diffraction device. | 05-03-2012 |
| 20120170439 | Objective Lens Element - An objective lens element having excellent compatibility with optical discs having different base material thicknesses is provided. The objective lens element has optically functional surfaces on an incident side and an exit side. At least either one of the optically functional surfaces on the incident side and the exit side includes a diffraction portion which satisfies at least either one of the following formulas (1) and (2): | 07-05-2012 |
| 20120182852 | OBJECTIVE LENS, OPTICAL HEAD, OPTICAL DISK APPARATUS, AND INFORMATION PROCESSING APPARATUS - An objective lens, an optical head, an optical disk apparatus and an information processing apparatus which can suppress deterioration of a focal spot caused by a drop in the diffraction efficiency are provided. An inner circumference area ( | 07-19-2012 |
| 20120213052 | OPTICAL HEAD, OPTICAL DISC DEVICE, INFORMATION PROCESSING DEVICE, AND OBJECTIVE LENS - Provided are an optical head capable of favorably recording or reproducing information to or from an information recording medium including a plurality of information recording surfaces, an optical disc device including the optical head, an information processing device including the optical disc, and an objective lens. The optical head ( | 08-23-2012 |
| 20120287767 | DIFFRACTION GRATING, ABERRATION CORRECTION ELEMENT AND OPTICAL HEAD DEVICE - There is provided a diffraction grating including a convex portion and a concave portion which are used for lights having different wavelengths λ | 11-15-2012 |
| 20130016598 | OPTICAL INFORMATION RECORDING/REPRODUCING APPARATUS AND OBJECTIVE OPTICAL SYSTEM FOR THE SAMEAANM YAMAGATA; NaokiAACI TokyoAACO JPAAGP YAMAGATA; Naoki Tokyo JPAANM INOUE; SatoshiAACI SaitamaAACO JPAAGP INOUE; Satoshi Saitama JPAANM TAKEUCHI; ShuichiAACI SaitamaAACO JPAAGP TAKEUCHI; Shuichi Saitama JP - An objective optical system for an optical information recording/reproducing apparatus, at least one surface of the objective optical system being configured to be a phase shift surface having a phase shift structure, wherein: the phase shift surface has a first area contributing to converging first, second and third light beams onto recording surfaces of first, second and third optical discs, respectively; in the first area, the phase shift surface has at least two types of phase shift structures including a first phase shift structure having first steps and a second phase shift structure having second steps; the phase shift surface has a plurality of combinations of annular zones which satisfy a condition: | 01-17-2013 |
| 20140153376 | OPTICAL PICKUP APPARATUS - An optical pickup apparatus which includes a light transmitting system is provided. A light source system provides the light transmitting system with light; a light receiving system includes detectors which are configured to detect light reflected from the multilayer optical disk; and a stray light controller is configured to prevent stray light from reaching the detectors. The stray light controller is disposed between the light source system and the light receiving system. The stray light controller includes a light transmitting portion through which light reflected from the multilayer optical disk and the stray light are configured to pass; a light diffraction portion is configured to diffract the light reflected from the multilayer optical disk and the stray light; and a light blocking portion configured to block the light reflected from the multilayer optical disk and the stray light. | 06-05-2014 |
| 20140233367 | METHOD OF ALIGNING LIGHT SOURCES IN AN OPTICAL PICKUP DEVICE, AND OPTICAL PICKUP AND OPTICAL DISC DRIVE EMPLOYING THE METHOD - Provided is an optical pickup device and a method of aligning a twin-light source in an optical disc drive. The method operates two light emitting chips in the light source simultaneously to cause two laser beams to be transmitted through a grating element at the same time. Location errors and rotation errors of the two light emitting chips with respect to the grating element may be corrected while monitoring the laser beams transmitted through the grating element. | 08-21-2014 |
| 20140241141 | OPTICAL PICKUP AND OPTICAL INFORMATION STORAGE SYSTEM INCLUDING THE SAME - Provided are an optical pickup and an optical information storage system including the same. The optical pickup includes a photodetector that receives a main light beam and a plurality of sub-light beams reflected from an information storage medium and diffracted by a diffracting element. The photo detector detects a tracking error signal using zeroth-order light as the main light beam and using one of first-order light and third-order light as the sub-light beam based on a type of an optical information storage medium. | 08-28-2014 |
| 20140269244 | OPTICAL HEAD, OBJECTIVE LENS, OPTICAL DISC DEVICE, COMPUTER, OPTICAL DISC PLAYER AND OPTICAL DISC RECORDER - An objective lens ( | 09-18-2014 |
| 20150131425 | OPTICAL OSCILLATION DEVICE AND RECORDING APPARATUS - Provided is a recording apparatus including a self-excited oscillation semiconductor laser that has a double quantum well separate confinement heterostructure and includes a saturable absorber section to which a negative bias voltage is applied and a gain section into which a gain current is injected, an optical separation unit, an objective lens, a light reception element, a pulse detection unit, a reference signal generation unit, a phase comparison unit, a recording signal generation unit, and a control unit. | 05-14-2015 |
| 369112060 | Sectioned optical element | 18 |
| 20110110216 | Optical Element, Aberration Correcting Element, Light Converging Element, Objective Optical System, Optical Pickup Device, and Optical Information Recording Reproducing Device - An optical system for use in an optical pickup apparatus comprises a first optical surface having a superposition type diffractive structure including a plurality of ring-shaped zones which are formed concentrically around an optical axis, wherein each ring-shaped zone is composed of a plurality of stepped sections stepwise, and a second optical surface having a diffractive structure including a plurality of ring-shaped zones which are formed concentrically around an optical axis, wherein each of the plurality of ring-shaped zones are divided by a stepped section to generate a diffractive light ray of diffractive order whose absolute value is not small than 1 for the light flux. | 05-12-2011 |
| 20110292782 | Optical Pickup Apparatus - An optical pickup apparatus comprising a first laser unit including a first laser light source and a second laser unit including second and third laser light sources, being respectively disposed on a reflection (transmitting) surface side and a transmitting (reflection) surface side of a first beam splitter, laser lights of the first, second, and third wavelengths being guided onto a common optical path through the first beam splitter and guided to the respective sorts of optical recording mediums, each of the laser lights being divided by a diffraction grating disposed on the common optical path into a main beam and sub-beams, a second beam splitter being disposed on the upstream side of the diffraction grating on a return path of each of the laser lights, the laser lights through the second beam splitter being branched from the common optical path and being received by a photodetector. | 12-01-2011 |
| 20120236701 | OBJECTIVE LENS FOR A COMBINATION THREE WAVELENGTH DISC DRIVE INCLUDING A BLU-RAY DISC READER AND A DVD/CD READER/WRITER, OPTICAL PICKUP INCORPORATING SAID OBJECTIVE LENS, AND A DISC DRIVE INCORPORATING SAID OPTICAL PICKUP - An objective lens for a slim type BD combo disc drive focuses a first light beam onto a first optical disc, a second light beam onto a second optical disc, and a third light beam having a third wavelength onto a third optical disc. The lens may include a first surface through which the first, second, and third light beams emitted from a light source enter the objective lens, and a second surface through which the first, second, and third light beams exit the objective lens and proceed toward the three corresponding optical discs. The first surface may include a diffractive surface which provides focus control in accordance with (i) 0th order light of the first and second light beams which are respectively focused onto the first and second optical discs, and (ii) 1st order diffracted light of the third light beam which is focused onto the third optical disc. | 09-20-2012 |
| 369112070 | Plural diffractive sections | 8 |
| 20080310284 | DIFFRACTIVE OPTICAL ELEMENT AND OPTICAL PICKUP APPARATUS - An optical pickup apparatus includes a diffractive optical element, and an objective lens that focuses a light beam of a first wavelength λ | 12-18-2008 |
| 20090080318 | OPTICAL INFORMATION RECORDING/REPRODUCING APPARATUS, DIFFRACTION-GRATING FABRICATING APPARATUS, OPTICAL INFORMATION RECORDING MEDIUM, AND POSITIONING CONTROL METHOD - An optical information recording/reproducing apparatus includes an optical mechanism that collects an information beam and a reference beam to an optical information recording medium that has a diffraction grating and an information recording layer by using interference fringes produced due to interference between the both beams which are converted from an irradiation beam for recording or reproduction and that guides a servo irradiation beam into the diffraction grating and causes the servo irradiation beam to be transmitted through the diffraction grating, a photodetector that detects a diffracted beam diffracted by the diffraction grating and transmitted therethrough, and an adjusting unit that controls a drive unit to adjust a position or an angle between the optical information recording medium and the optical mechanism based on the intensity of the detected diffracted beam. | 03-26-2009 |
| 20100238780 | OPTICAL PICKUP DEVICE - A pickup device includes a diffraction grating | 09-23-2010 |
| 20110103216 | High data density optical recording medium - The present invention relates to a high data density optical recording medium. The invention further relates to an apparatus for reading from such an optical recording medium. The optical recording medium has marks that are arranged in tracks. The tracks have a cross section with a curved shape and protrude above a surface of the optical recording medium. | 05-05-2011 |
| 20110188367 | OPTICAL PICKUP DEVICE - An optical pickup includes a collimator lens having a diverging lens and a converging lens, such that it maintains a constant focal length and has a short optical path length. The collimator lens of the optical pickup device includes a diverging lens located at the side of a light source and a converging lens located at the side of generating parallel light or gentle oscillation light. In addition, the diverging lens and the converging lens of the collimator lens may be integrated, or may also be formed of a hologram optical element. As a result, the optical pickup device can be configured in the form of a slim structure using the collimator lens having a short optical path length. | 08-04-2011 |
| 20130016599 | OPTICAL PICKUP DEVICE AND OPTICAL DISC APPARATUS - Optical pickup device including: semiconductor laser diode emitting optical flux; objective lens converging flux emitted from the diode and radiating flux to an optical disc; diffraction grating branching an optical flux reflected from the disc; and a photodetector receiving flux branched by the grating and has a plurality of light receiving parts, wherein: the grating has areas A, B and C; among diffracted beams diffracted by a track of the optical disc, only a 0-th order diffracted beam becomes incident upon area A, and 0-th and ±1-st order diffracted beams become incident upon area B; the photodetector detects a reproduction signal from optical fluxes diffracted in areas A, B and C; the plurality of light receiving parts which detect the +1-st order diffracted beam or the −1-st diffracted beam diffracted in area A are aligned in a direction substantially perpendicular or parallel to a track direction of the disc. | 01-17-2013 |
| 20140098656 | OPTICAL ELEMENT - An optical element has at least one surface divided into a plurality of regions and includes: a first region configured to converge light with a wavelength λ | 04-10-2014 |
| 20150138942 | OPTICAL DISK INFORMATION DEVICE AND INFORMATION PROCESSING DEVICE - An optical disk information device includes a laser light source that emits a luminous flux with a wavelength λ, an objective lens having a numerical aperture NA, a splitting element, a photodetector, a central portion amplifier, at least two end portion amplifiers, an adder, a control signal processing section having as tracking switcher that inverts a polarity of a tracking control signal depending on whether a track scanned by a condensing spot corresponds to a land portion or a groove portion, and a gain controller that, when the polarity of the tracking control signal is inverted, switches gains of the central portion amplifier and the end portion amplifiers and sets the gain of the central portion amplifier substantially lower than the gain of at least one of the end portion amplifiers so as to reduce crosstalk from adjacent tracks in the optical disk. When a groove pitch in the optical disk is denoted by Gp, (Gp/2)<(1.2•λ)/(2•NA) is satisfied. | 05-21-2015 |
| 369112080 | Lens section | 6 |
| 20090016195 | Optical pickup apparatus, recording/reproducing apparatus provided with the optical pickup apparatus, optical element, and information recording/reproducing method - An optical pickup apparatus for reproducing information from an optical information recording medium or for recording information onto an optical information recording medium, is provided with a first light source for emitting first light flux having a first wavelength; a second light source for emitting second light flux having a second wavelength, the first wavelength being different from the second wavelength; a converging optical system having an optical axis and a diffractive portion, and a photo detector; wherein in case that the first light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the first light flux is greater than that of any other ordered diffracted ray of the first light flux, and in case that the second light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the second light flux is greater than that of any other ordered diffracted ray of the second light flux, where n stands for an integer other than zero. | 01-15-2009 |
| 20090207715 | Optical element, optical pickup device and optical information recording and reproducing apparatus - An optical element for use in an optical pickup device to conduct reproducing and/or recording information for a first disk including a protective substrate by the use of a first light flux emitted from a first light source and to conduct reproducing and/or recording information for a second disk including a protective substrate by the use of a second light flux emitted from a first light source, the optical element includes: an optical surface on which a first phase structure is formed to have a function to correct a spherical aberration; an optical surface on which a second phase structure is formed such that when the wavelength of the first light flux changes, the second phase structure generates a spherical aberration in a direction reverse to the direction of a spherical aberration generated by the first phase structure. | 08-20-2009 |
| 20090310465 | OPTICAL HEAD AND OPTICAL INFORMATION DEVICE - An optical head according to the present invention includes: a first light source that emits light with a first wavelength; a beam splitter that splits the light emitted from the first light source into a first light beam traveling in a first direction and a second light beam traveling in a second direction different from the first direction; a first collimator lens for changing degrees of divergence of the first light beam; a first mirror that changes the traveling directions of the first light beam, of which the degrees of divergence have been changed; a first objective lens for converging the first light beam, which has had its traveling directions changed, toward a storage layer of a first optical disk; a mover that holds the first objective lens; a first photodetector that receives the first light beam reflected from the storage layer of the first optical disk and converts it into an electrical signal; a condenser lens for condensing the second light beam; and a second photodetector that receives the second light beam condensed by the condenser lens and converts it into an electrical signal. | 12-17-2009 |
| 20090316563 | OBJECTIVE LENS, OPTICAL PICKUP APPARATUS AND OPTICAL INFORMATION RECORDING AND/OR REPRODUCING APPARATUS - An objective lens according to the present invention is an objective lens used for an optical pickup apparatus, and the objective lens includes a superimposed structure on a surface of a lens with a power in which a first optical path difference providing structure changing spherical aberration in under-corrected direction when a wavelength of an incident light flux becomes longer, and a second optical path difference providing structure changing spherical aberration in over-corrected direction when a wavelength of an incident light flux becomes longer are superimposed. | 12-24-2009 |
| 20100135145 | Optical Pickup Apparatus and Optical Disc Apparatus Including the Same - An optical pickup apparatus comprising at least: a diffraction grating configured to split first wavelength light into at least a first main beam and first sub-beam, and to split second wavelength light into at least a second main beam and second sub-beam, the diffraction grating including a diffraction surface portion corresponding to the second wavelength light; and a photodetector including a first main light-receiving unit configured to be applied with the first main beam, a first sub-light-receiving unit configured to be applied with the first sub-beam, a second main light-receiving unit configured to be applied with the second main beam, and a second sub-light-receiving unit configured to be applied with the second sub-beam, a distance between the first main light-receiving unit and first sub-light-receiving unit being changed relative to a standardized distance between the first main light-receiving unit and first sub-light-receiving unit. | 06-03-2010 |
| 20110194396 | OPTICAL PICKUP APPARATUS, OBJECTIVE OPTICAL ELEMENT AND OPTICAL INFORMATION RECORDING REPRODUCING APPARATUS - An optical pickup apparatus according to the present invention includes: a first light source for emitting a first light flux; a second light source for emitting a second light flux; a third light source for emitting a third light flux; and an objective optical element. The objective optical element has an optical surface including at least two areas provided with optical path difference providing structures. The objective optical element converges the first to third light fluxes each passing through the predetermined areas on the objective optical element onto respective information recording surfaces of the first to third optical disks. The optical pickup apparatus provides a wavelength dependency of a spherical aberration so as to correct a change in a spherical aberration due to a refractive index change with a temperature change of the objective optical element. | 08-11-2011 |
| 369112090 | Prism, mirror, or waveguide section | 1 |
| 20120069725 | OPTICAL PICKUP APPARATUS - In an optical pickup apparatus, a major part of an optical path of a laser beam emitted from a first semiconductor laser device and an optical path of a laser beam emitted from a second semiconductor laser device | 03-22-2012 |
| 369112100 | Holographic | 1 |
| 20080239924 | OPTICAL DISC APPARATUS AND METHOD FOR REPRODUCING INFORMATION - An optical disc apparatus reproducing information on the basis of a standing wave recorded on a disc-like volume type recording medium is disclosed. The apparatus includes: first focus position adjusting means for adjusting the position of a focus on which a first light beam focuses inside a recording layer inside the volume type recording medium in the optical axis direction of the first light beam; second focus position adjusting means for adjusting the position of a focus on which a second light beam focuses inside the recording layer in the optical axis direction of the second light beam; controlling means for controlling the first focus position adjusting means and the second focus position adjusting means; and first and second detecting means for detecting the first and second reproduction light beams. | 10-02-2008 |
