Patent application number | Description | Published |
20090135687 | OPTICAL HEAD, CONTROL METHOD FOR OPTICAL HEAD, AND OPTICAL INFORMATION PROCESSING APPARATUS - An optical head includes a hologram which extracts, from a luminous flux of reflected light from an optical disk, at least a first luminous flux branch which does not include the optical axis of the luminous flux; and a photodetector which receives the reflected light from the optical disk and produces signal output, wherein the photodetector has light-receiving areas which receive the first luminous flux branch of reflected light from an optical information recording medium layer targeted for recording or playback out of the plurality of optical information recording medium layers of the optical disk, the light-receiving areas are placed in such a way that the signal output resulting from a light spot formed by the first luminous flux branch of the reflected light from the optical information recording medium layer targeted for recording or playback is practically the same between the first and second photodetection areas, and a boundary line of the light-receiving areas is located in such a position as not to include light spots formed by luminous fluxes of reflected light from the optical information recording medium layers other than the optical information recording medium layer targeted for recording or playback. | 05-28-2009 |
20090257340 | OPTICAL HEAD - To provide an optical head to produce good servo and read signals by reducing the influence of interference by light reflected from a non-read layer of a multilayer optical disc. | 10-15-2009 |
20090262630 | OPTICAL CONTROL DEVICE, OPTICAL INFORMATION RECORDING/REPRODUCING DEVICE, OPTICAL INFORMATION RECORDING MEDIUM AND OPTICAL HEAD CONTROL METHOD - An optical controller includes a light source for emitting light, an object lens for condensing light emitted from the light source, a light detection unit for receiving light reflected on an optical information recording medium and outputting a signal corresponding to the amount of the light, and a laser control unit for controlling the amount of the light emitted from the light source to the information recording surface on which information is to be recorded or reproduced, based on the recording state of an information recording surface disposed closer to the object lens than an information recording surface on which the information is to be recorded or reproduced. | 10-22-2009 |
20090268588 | OPTICAL HEAD, OPTICAL INFORMATION RECORDING AND REPRODUCING DEVICE, AND OPTICAL INFORMATION SYSTEM DEVICE - 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. | 10-29-2009 |
20100254236 | OPTICAL HEAD DEVICE, AND RECORDING AND/OR REPRODUCING DEVICE - An object of the invention is to suppress an influence of a wavefront aberration which is generated at the time of correcting a third-order spherical aberration, and realize satisfactory information recording and/or reproducing. A collimator lens | 10-07-2010 |