Abstract: A recording medium having at least a lead-in area, a data recording area to which data is recorded, and a lead-out area, wherein the data recording area comprises a first recording area portion to which data that has been encoded with an error correction code is recorded; and a second recording area portion to which at least data that has been encoded with a plurality of types of generation polynomials as error correction codes.

Abstract: A DVD audio data structure following high-sound-quality specifications is realized, making the best use of the audio data structure standard in DVD video. A first sample data string created by digitizing a first channel audio signal at a first sampling frequency in a first number of quantization bits, a second sample data string created by digitizing a second channel audio signal at a second sampling frequency in a second number of quantization bits, and header data including timing data to synchronize the first sample data string with the second sample data string are recorded on a recording medium.

Abstract: A recording medium storing a write protection information, and a write protection method for protecting data recorded on a recordable and/or rewritable disc from unwanted overwriting or erasing. In order for write protection of a disc in a bare state that is usually used in a cartridge having a recognition switch for write-protection, such as a DVD-RAM, write protection information is recorded in a Lead-in area, a Lead-out area or a recording information area other than a user data area of the disc, and the data is protected from unwanted overwriting or erasing using the write protection information. Also, even though the write protection information stored on a disc does not match the state of a recognition switch of a case for write-protection, the data can be prevented from unwanted overwriting or erasing. Thus, the write protection can be ensured when a recordable and/or rewritable recording medium, such as DVD-RAM, DVD-R and DVD-RW, is used in a bare state.

Abstract: Audio-centered information is stored on a unitary medium by using a Table-of-Contents (TOC) mechanism that specifies an actual configuration of various audio items on the medium. In particular, each one of a set of one or more Track Areas gets at least two mutually logically conforming Sub-TOCs assigned. This allows to retrieve any constituent Sub-TOC part from at least any correct copy of the Sub-TOCs. Furthermore, one or more Master-TOCs are provided for specifically pointing to each of the Sub-TOCs.

Abstract: An optical reproducing apparatus that uses a hologram laser module and is applicable to a DVD Multi drive, wherein five sub spots of light in total that are most suitable to perform the differential push-pull tracking both for DVD-RAM and for DVD-R/RW are irradiated on the disk, respectively, and influence of several sub spots that are unnecessary in recording and reproducing a disk is canceled out by calculation, to realize an optical head that is compatible with the DVD Multi drive using a hologram laser module, and thereby providing a small-size, high-performance optical reproducing apparatus.

Abstract: A data recording/reproducing apparatus wherein various data to be used for maintenance are measured, and parameters required for analysis of the maintenance data are prerecorded to realize prediction of the service life of a semiconductor laser and detection of occurrence of any trouble that may be derived therefrom. In this apparatus where data are recorded in and/or reproduced from a recording medium, the internal state of the apparatus is measured, then any abnormal state in the apparatus is detected on the basis of abnormal state decision data, and the detected state is transmitted to an external information processor. The apparatus comprises a means for measuring first data relative to the apparatus; a first memory means for storing second data to make a decision as to an abnormal state of the measured first data; a means for generating third data relative to maintenance of the apparatus on the basis of the first and second data; and an output means for delivering the third data as an output.

Abstract: A molecular memory media having a media surface and a platform with read/write heads. The platform and media are moved to allow one of addition, removal, and repositioning of atoms, electrons, and charges on a surface of the media. The media is a material capable of storing data written to it, and detectable using a vibrating tip sensor that resonates at a free space value which is phase shifted when charges or anomalies on a surface of the media are present. Other methods of reading and writing to the media are presented. The media may be enhanced by augmenting grain boundaries of the media vis deposition and removal of PMMA materials. Servo trenches and sync bits identify positions of the read/write heads and maintain alignment during memory operations.

Abstract: A tracking control apparatus comprises an signal processing section, a lens characteristic measuring section and an optimum lens position searching section. The lens characteristic measuring section acquires a first address and second address of an optical disk. The lens characteristic measuring section successively generates offset set values so that the position of a converging lens is moved by an actuator at predetermined spatial intervals and counts the number of times both the first address and the second address are acquired. The optimum lens position searching section searches for a maximum value of the acquisition count and moves the converging lens using the actuator based on the offset set value when the acquisition count reaches a maximum value.

Abstract: A substrate for an optical recording medium includes recording tracks formed in guide grooves on a disc and an address section having an address pit sequence formed between the recording tracks in the guide grooves along an information reading direction of the recording tracks. The recording tracks in the guide grooves are divided into a prescribed number of zones. In each of the zones, the center of the address section corresponding to a recording track in the radially outermost or radially innermost guide groove is disposed so as to shift in a radial direction of the disc in relative relationship to the center of the recording track in the guide groove.

Abstract: If data is recorded using a disc with deviating characteristics and a recorder with deviating characteristics, data will not be appropriately recorded, and errors will occur in the read signal. Standard recording pulse parameters specifying recording pulse positions for plural possible mark length and space length combinations are read from a writable optical disc, these standard recording pulse parameters are then used for test writing, the standard recording pulse parameters are changed uniformly or individually, a best recording pulse parameter is thus obtained, and jitter can be reduced.

Abstract: According to the present invention, an optical pickup device forms one main spot, a first subspot, and a second subspot by irradiation of light on an optical disk having a groove part and a land part. The optical pickup device includes operation circuits which indicate a deviation between each of the optical spots and a track, and ? detecting means for detecting such an ? value that a difference in absolute value between SPP1 and ?SPP2 falls in a preset range, where an AC amplitude of a push-pull signal of the first subspot is SPP1, and an AC amplitude of a push-pull signal of the second subspot is SPP2, wherein SPP1??SPP2 (? is a constant) is a land/groove discriminating signal. With this, in the optical pickup device for recording and reproducing information on/from the optical disk having a land/groove part, it is possible to generate a land/groove discriminating signal and a tracking error signal without an offset, thereby performing excellent tracking control.

Abstract: The invention provides a disk playback device wherein a disk (1) is irradiated with a laser beam from an optical head (4) to reproduce signals from the disk, and which comprises an external synchronizing signal producing circuit (8) and a delay circuit (12) for producing a reproduction synchronizing signal providing reference timing at which a reproduced signal is detected by reading an output signal from the optical head (4), a circuit (7) for detecting the reproduced signal by reading the output signal from the optical head (4) based on the reproduction synchronizing signal, and a system controller (10) for determining an optimum phase for a normal reproduction operation by altering the phase of the reproduction synchronizing signal and executing a reproduction operation, the controller (10) being operable to make a phase adjustment for the reproduction synchronizing signal prepared by the delay circuit (12).

Abstract: An optical disc player executes a focus pull-in operation while avoiding an inconvenience that an objective lens comes into contact with an optical disc, or the like. The objective lens is forcedly moved gradually from a position that is away from the surface of the optical disc and outside a capture range of a focus servo toward the surface of the optical disc. When the objective lens reaches the capture range of the focusing servo loop by the moving operation and a distance between the objective lens and the disc surface is at the minimum distance or is changing in a widening direction, the moving operation of the objective lens is stopped.

Abstract: A recording and reproducing apparatus of the present invention includes a photo-detector having light receiving sections divided along the track direction of an optical disk. The apparatus also includes a wobble signal processing circuit for generating a wobbling polarity judging signal used in judging a wobbling polarity of a track being tracked by comparing phases of a first wobble signal detected from a difference signal of the outputs of the light receiving sections and a second wobble signal detected from a sum signal of the outputs of the light receiving signals. Consequently, whether the wobbled side wall of the track being tracked is the inner or outer radius of track can be judged in real time by a simple structure using one laser beam.

Abstract: A recording medium including a resin substrate having a first thermal expansion coefficient, a center hole, a first surface, and a second surface opposite to the first surface, a recording layer formed on the first surface of the resin substrate and having a recording region, an inner nonrecording region formed inside the inner periphery of the recording region, and an outer nonrecording region formed outside the outer periphery of the recording region, and a protective layer formed on the second surface of the resin substrate except an inner peripheral region having a predetermined range from the center hole, the recording region, and the outer nonrecording region. The thermal deformation suppressing layer has a second thermal expansion coefficient smaller than the first thermal expansion coefficient.

Abstract: If data is recorded using a disc with deviating characteristics and a recorder with deviating characteristics, data will not be appropriately recorded, and errors will occur in the read signal. Standard recording pulse parameters specifying recording pulse positions for plural possible mark length and space length combinations are read from a writable optical disc, these standard recording pulse parameters are then used for test writing, the standard recording pulse parameters are changed uniformly or individually, a best recording pulse parameter is thus obtained, and jitter can be reduced.

Abstract: A high-speed, write-once type optical recording medium, which utilizes laser light that is either blue or an even shorter wavelength, as well as an optical recording method and an optical recording apparatus for recording onto this optical recording medium. A high-speed, write-once type optical recording medium 10 having a recording layer 18 and a light transmission layer 22 formed sequentially on top of a support substrate 12, wherein the recording layer 18 is formed by laminating first and second vice-recording layers 18A, 18B which include Al and Sb respectively as primary components, and irradiation of a laser light of blue wavelength from a laser light source 24, through the light transmission layer 22 and onto the recording layer 18, causes diffusion and mixing of the Al and Sb contained within the first and second vice-recording layers 18A, 18B, and this mixing enables the formation of a recording mark based on an irreversible change in reflectance.

Abstract: A stabilization part stabilizes surface vibration of a flexible optical disk along a rotation axis direction of the optical disk by means of pressure difference of air flow created according to Bernoulli's law at a portion on which information writing/reading is performed, provided on a side of the optical disk opposite to a side on which information recording/reproducing is performed. In this case, areas are provide on the upstream side and down stream side along the disk rotation direction of the portion of the optical disk which is stabilized by said stabilization part, said areas of the optical disk not having pressure difference created thereon by the air flow.

Abstract: A light emitting device according to the present invention includes: a first light source for emitting light having a first wavelength; and a second light source for emitting light having a second wavelength which is different from the first wavelength, wherein the first light source and the second light source are arranged in the same housing, and a relationship of ?h1>?h2 is satisfied, where ?h1 denotes an angle (full-width-half-maximum) of radiation of the light emitted from the first light source in the horizontal direction, and ?h2 denotes an angle (full-width-half-maximum) of radiation of the light emitted from the second light source in the horizontal direction.

Abstract: This invention relates to a reproducing apparatus compatible with a storage medium storing copyright-protected and copyright-unprotected files, the reproducing apparatus being capable of reproducing any one of the files stored on the medium, the reproducing apparatus comprising: demodulating means for demodulating any one of the copyright-protected files in one way and any one of the copyright-unprotected files in a different way; selective operation executing means operated to select either any one of the copyright-protected files or any one of the copyright-unprotected files as a file to be reproduced; and controlling means for causing the demodulating means to select one of the two different ways of demodulation depending on whether a copyright-protected file or a copyright-unprotected file has been selected by operation of the selective operation executing means.