Abstract: An optical pickup apparatus comprises first, second and third light sources to emit light fluxes of wavelength ?1, ?2 and ?3 for conducting recording and/or reproducing information for first, second and third optical information recording mediums having respective protective substrates of thickness t1, t2 and t3 and a diffractive optical element located on a common optical path for the first, second and third light sources. A converged-light spot is formed on the first optical information recording medium with m-th order diffracted-light ray of the wavelength ?1, on the second optical information recording medium with n-th order diffracted-light ray of the wavelength ?2, and on the third optical information recording medium with k-th order diffracted-light ray of the wavelength ?3 generated by the diffractive optical element respectively, wherein one of m, n and k is different from one of other two numbers.

Abstract: An optical head device is provided with a semiconductor laser, an aberration correcting element for transmitting a beam from the semiconductor laser, a light guiding portion for introducing the beam from the semiconductor laser to the aberration correcting element, and an objective lens for focusing the beam having passed through the aberration correcting element on an optical disc. The aberration correcting element corrects a longitudinal chromatic aberration occurring in the objective lens and a longitudinal chromatic aberration occurring in the light guiding portion excluding the objective lens and the aberration correcting element based on a longitudinal chromatic aberration occurring in the aberration correcting element when the semiconductor laser emits a beam having a wavelength different by a specified wavelength difference.

Abstract: Methods, software, and apparatus for the calibration of writing characteristics for writing to an optical storage medium, and methods of encoding calibration pattern data and calibration instructions are disclosed. The method of calibration generally includes the steps of (a) receiving pattern data and instructions synchronized with the pattern data, (b) writing the pattern data to the optical storage medium in accordance with the instructions, (c) reading a readback signal corresponding to the pattern data from the optical storage medium, (d) processing the readback signal in accordance with the instructions, and (e) determining a value of a writing characteristic for writing data to the optical storage medium based at least in part on the readback signal. The method provides the ability to flexibly set test parameters and to quickly and accurately test the write characteristics of a recordable or re-writable optical storage medium.

Abstract: In an exemplary embodiment of the present invention, after test write is performed with a predetermined test power to a first track on an optical disk, test write is performed with the same test power as the first track to a second track adjacent to the first track. Then, reproduction signals are obtained by reproducing the first track and the second track respectively, and a determination whether or not the test power is set to a recording laser power in recording main information is made based on a relationship between the obtained reproduction signals.

Abstract: An objective lens drive includes a lens holder holding first and second objective lenses and moved at least in a focusing direction substantially parallel to optical axes of the objective lenses and in a tracking direction orthogonal to the focusing direction; a support supporting the lens holder movably at least in the focusing and tracking directions; a first adjusting unit provided between the first objective lens and the lens holder and adjusting a tilt of the first objective lens in a direction about an axis in a first direction being any direction in a plane orthogonal to the focusing direction; and a second adjusting unit provided between the second objective lens and the lens holder and adjusting a tilt of the second objective lens in a direction about an axis in a second direction being in a plane orthogonal to the focusing direction and substantially orthogonal to the first direction.

Abstract: An optical pickup device includes: a light source that emits a light beam; a divergence-angle converting lens that converts an angle of divergence of the light beam emitted from the light source and emits the light beam; and an object lens displaceable in a tracking direction that receives incidence of the light beam, the angle of divergence of which is converted by the divergence-angle converting lens, and converges and emits the light beam, wherein spherical aberration equivalent to an amount that can offset astigmatism caused when the object lens is displaced is given to the divergence-angle converting leans, and spherical aberration that can offset the spherical aberration given to the divergence-angle converting leans is given to the object lens and comatic aberration that can offset comatic aberration caused by the spherical aberration given to the divergence-angle converting lens when the object lens is displaced is given to the object lens.

Abstract: The length of a format modulation area in an address segment is limited to be 25% of the address-segment length or less, and the position of the format modulation area is selectable two possible positions. Subsequently, where a CLV optical-disk medium is used, wobble modulation areas in adjacent recording tracks do not overlap each other in the radius direction.

Abstract: This invention provides a method and a system to read and buffer an audio data file from an optical storage medium into a buffer memory. The data file comprises blocks sequentially stored in the medium. Each block comprises a subcode block with encoded subcodes and a corresponding main data block with encoded audio data. The method first designates a starting block where buffering starts and searches for the starting block in the blocks. After the starting block is searched, trigger a main data block decoding procedure to decode the starting block and main data blocks in later blocks. According to the timing when the main data block decoding procedure is triggered, decide the timing to trigger buffering the decoded subcodes to the buffer memory. Therefore, the subcodes and corresponding audio data belonging to the same block before decoding can be buffered into the same buffer unit after decoding.

Abstract: An optical pickup device includes an objective lens (1) for focusing a light flux onto an information layer of a disk-shaped medium, an objective lens driving unit that drives the objective lens (1) in a focus servo direction and in a tracking servo direction, a correction lens (14) disposed on the same optical axis as the objective lens (1), and a correction lens driving unit that drives the correction lens (14) in the same direction as the focus servo direction to control the condition of the light flux incident on the objective lens.

Abstract: An optical disc of a desired thickness is formed by adhering a stamper substrate 20 to an L0 layer substrate 10. Concave/convex portions to transfer fine concave/convex portions for an L1 layer are formed on one principal plane of the stamper substrate 20. After the fine concave/convex portions for the L1 layer were transferred and formed onto an intermediate layer 32 by the stamper substrate 20, the stamper substrate 20 is adhered to the L0 layer substrate 10.

Abstract: The optical pickup includes two objective lenses, and an objective lens holder that holds the two objective lenses. The objective lens holder has two fixture holes that pass through from the lower surface to the upper surface to which the two objective lenses are attached at an upper portion with space between them. The fixture hole is provided with a fixed lens supporting portion and two movable lens supporting portions for supporting the objective lens and adjusting tilt degree thereof. The movable lens supporting portion includes a through hole that passes through to the upper portion of the fixture hole and a column member that is inserted in the through hole in a slidable manner.

Abstract: An offset-free tracking signal enables stable tracking control even if an optical disc is a multi-layer disc having three or more layers. Light receiving portions of a main region light receiving portion group are arranged between a projection line of a third dividing line on a photodetector and a projection line of a fourth dividing line on the photodetector by stray lights from information layers adjacent to the one, on which a light beam is focused, out of a plurality of information layers. Further, light receiving portions of a subregion light receiving portion group is arranged between a projection line of a first dividing line on a photodetector and a projection line of a second dividing line on the photodetector by the stray lights from the information layers adjacent to the one, on which a light beam is focused, out of the plurality of information layers.

Abstract: By use of a substrate which can be stably formed and has a relatively small groove depth, a very high density optical recording medium having good recording/reading characteristics is provided. In an optical recording medium of a surface incidence type, in which a reflective layer, a recording layer containing a dye as a main component and a cover layer are sequentially formed on a substrate having guide grooves formed therein, a guide groove part on a far side from a plane of incidence of a recording/reading light beam on the cover layer is set as a recording groove part, and reflected light intensity in a recorded pit portion formed in the recording groove part is increased by a phase shift and is set higher than reflected light intensity in unrecorded.

Abstract: A multi-layer information storage medium 600 includes: a data-reading surface; and eight recording layers 601 to 608 for recording data which is read out by using a blue-violet light beam. Each of the recording layers 601 to 608 has a user data area 610. A recording layer which is the most distant from the data-reading surface 601 includes a disk information area 26 and a defect management area 27 for recording management information concerning all of the recording layers 601 to 608.

Abstract: A disc with a temporary defect management information area and a defect management area includes a defect management area that is present in at least one of a lead-in area, a lead-out area, and an outer area, a temporary defect information area which is formed in the data area and in which temporary defect information is recorded, and a temporary defect management information area which is present in at least one of the lead-in area, and the lead-out area. Accordingly, it is possible to record user data in a recordable disc, especially, a write-once disc, while performing defect management thereon, thereby enabling efficient use of a defect management area having a limited recording capacity.

Abstract: An optical pickup includes a diffraction grating partitioned into three areas, in which the phase of periodic grating groove structure in an area is successively shifted from that in the adjacent area by 90°. In the generation of a differential push-pull signal, an amplification factor K for sub push-pull signals is varied depending on the type of the optical disk. By such composition of the optical pickup, amplitude deterioration of the tracking error signal accompanying displacement of the object lens is reduced.

Abstract: A method for storing information, in particular audio signals, received via radio, in particular broadcast radio, the received information being written to a first memory, where the information stored in the first memory is overwritten by newly received information, preferably no later than when the memory capacity of the first memory is exceeded by the sum of the information stored in the first memory, and where in response to a record command all or part of the information present in the first memory is transferred into a second memory. As a result, even when playback of information which is of interest to the user has already begun, the latter can nevertheless record the entire information unit, for example the whole piece of music, part of which has already been played back, in its entirety right from the beginning.

Abstract: Disclosed herein is an optical pickup device. In an embodiment of the present invention, sub beams from which an AC component has been removed are generated using a first diffractive element based upon properties that a beam incident on a disc is reflected with being separated by the track structure of the disc, and beams reflected from adjacent layers are prevented from being diffracted to sub cells for receiving the sub beams using a second diffractive element. In this case, the grating direction of the first diffractive element and the second diffractive element is adjusted, and thus the influence of dead zones generated in a tracking error signal due to the second diffractive element is removed.

Abstract: An information recording apparatus (300) is for recording record information onto an information recording medium (100) comprising a first recording layer (L0 layer) and a second recording layer (L1 layer) to record therein the record information by irradiating laser light. The information recording apparatus is provided with: a recording device (352) for recording the record information into at least one of the first recording layer and the second recording layer by irradiating the laser light; and a controlling device (354) for controlling the recording device to record the record information into a target area (115a), which is a recording area of the second recording layer corresponding to a recording area (105a) of the first recording layer in which the record information is recorded, if the record information is recorded into the second recording layer.

Abstract: In the first and second light-receiving regions equally divided into two in parallel with the track of the optical disc, the reflected light received from the optical disk is converted into electric signals and fed out by individual light-receiving regions. Then, the light-receiving ratio indicating the ratio of amounts of received light is calculated from the amplitude of the electric signal generated in the first light-receiving region and the amplitude of the electric signal generated in the second light-receiving region. Then, it is determined whether or not an absolute value of the light-receiving ratio is larger than a predetermined vale. When the absolute value is larger, the movement of the objective lens in a radial direction is corrected by incorporating a predetermined correction value.