Abstract: A magneto-optical record medium and a reproducing apparatus for the same allow data reproduction having good characteristics by a simple structure. The magneto-optical record medium includes a plurality of first grooves (3) each having sidewalls, at least one of which is wobbled in accordance with address information; an address mark (21) formed by changing a width of a land located between second grooves connected to the first grooves; and third grooves wobbled cyclically, formed in a data portion magnetically storing data and connected to the second grooves. The reproducing apparatus reproduces the data from the magneto-optical record medium.

Abstract: There is provided an optical disc having preformed thereon a spiral wobbled track as a grove and/or land along with data is to be recorded. The track is wobbled for a series of predetermined signal units each composed of an FSK information bit part based on a waveform resulted from FSK modulation of information bit and a singe-frequency part based on a waveform of a single frequency. The FSK modulation uses two different frequencies of which the one is the same as the single frequency and the other is different from the single frequency. These different frequencies are in such a relation that each of them has an even number of wobbles and an odd number of wobbles alternately in a predetermined cycle.

Abstract: An optical disc having a data area in which information signals are recorded, a lead-in area and a lead-out area provided before and after the data area, and a program memory area for temporarily storing address information necessary for additionally writing information signals. A subcode Q of the lead-in area or a subcode Q of the program memory area is provided with identification information for identifying these subcodes Q. For example, the identification information is provided at least in one of address (ADR), track number (TNO), and zero (ZERO) constituting the subcode Q of the program memory area or the lead-in area. Thus, it is possible to discriminate the subcode Q of the program memory area and the subcode Q of the lead-in area securely and instantaneously.

Abstract: A method for reading address information from an optical disc with a wobbled track groove includes the steps of: obtaining a sine wave address signal, a first address signal representing a first groove region with sine wave wobbled portions and an inverted phase portion, and a second address signal representing a second groove region with steep inward or outward displacements; multiplying a first reference signal, being phase-locked to, and having the same frequency as, the sine wave address signal, and the first address signal together to obtain a first multiplied signal; multiplying a second reference signal, being phase-locked to, and having a frequency twice as high as, the sine wave address signal, and the second address signal together to obtain a second multiplied signal; integrating the first and the first address signal 405, the second address signal 406 second multiplied signals separately to obtain a first integral and a second integral, respectively; and adding the first and second integrals toget

Abstract: An apparatus and a method for detecting address information are provided. The apparatus for detecting address information from an optical disc on which a plurality of sectors are arranged and pre-pit data are recorded on each sector, includes: a window generation circuit for generating a detection window for detecting the pre-pit data; a data detection circuit for detecting the pre-pit data based on the generated detection window; a latch for latching the data detected by the data detection circuit to a larger number of bits than a pre-allotted number of bits; a synch information extraction circuit for generating synch information informing a time to refer to the latched data; and an address information extraction circuit for detecting address information by reading the latched data based on the generated synch information. Therefore, the address information recorded on an optical recording medium as land pre-pit (LPP) data can be efficiently detected.

Abstract: An address decoder includes a PLL circuit generating a PLL clock signal synchronized with an external clock signal, a frequency divider dividing the PLL clock signal, a selector selecting a binary wobble signal or an inverted signal thereof, a timing generator generating each of sync window signals, a biphase enable signal, CRC enable signals, a CRC polarity signal, and an output enable signal, a biphase decoder decoding a wobble signal selected by the selector, a Gray code decoder decoding a biphase decode data, and an output control circuit outputting a decoded address signal. Therefore, this address decoder can reproduce an address signal by decoding the wobble signal.

Abstract: At the time of heterodyne detection, information is reproduced constantly in the optimum condition. A method reproduces information recording medium including a reference wobble block which has a first wobble pattern representing a first information content; and an information wobble block which follows the reference wobble block and which has at least one of the first wobble pattern and a second wobble pattern representing a second information and different from the first wobble pattern. The method includes reading the reference wobble block and the information wobble block; comparing a wobble pattern read from the information wobble block with the first wobble pattern of the reference wobble block; judging that information recorded in the information wobble block is the first information or the second information according to the wobble pattern read from the information wobble block; and outputting one of the first and the second information based on the judging result.

Abstract: In step S1, the address generator generates address information composed of a sync signal which is recorded on an optical disc, address data and an error correction code for the address data, pre-encodes and supplies it to a modulator. At the same time, a carrier signal generator generates a carrier signal which is to carry the address information, and supplies it to the modulator. In step S2, the modulator makes MSK modulation of the carrier signal supplied from the carrier signal generator on the basis of the pre-encoded address information supplied from the address generator, and supplies a resultant MSK modulation signal to a wobbling unit. In step S3, the wobbling unit forms, on the optical disc, a spiral groove wobbled adaptively to the MSK modulation signal supplied from the modulator. In this optical disc, a given address can be accessed quickly and accurately.

Abstract: An ATIP (absolute time in pre-groove) bit data generator free from an uneven duty cycle. The ATIP bit data generator includes an analog processor, a high-frequency clock generator, a first decoder, a sync pattern detector, and a second decoder. The analog processor receives a signal generated from an optical pickup, and further processes the signal to generate an ATIP FM signal. The high-frequency clock generator provides a high-frequency clock using the ATIP FM signal as a reference signal. The first decoder receives the ATIP FM signal and the high-frequency clock and generates bi-phase data. The sync pattern detector receives the bi-phase data and the high-frequency clock, and generates a sync indication signal. The second decoder counts the pulse number of the high-frequency clock for each counting cycle, and the counting cycle includes a plurality of half periods of the ATIP FM signal.

Abstract: Methods for processing and recording data files to an optical disc media are provided. In one example, a method includes the operations of processing data files selected to be recorded and generating a file system database. The file system database generates information about the source data files, and in response to a request for a number of sectors of data, reads the requested sectors of data one at a time into a system memory buffer. The file system database writes a subheader for each of the sectors of data after each sector is written into a memory location that is before each data sector. The sectors and subheaders are then written to an optical disc media. In another example, a computer readable media is provided having program instructions for recording data on an optical disc. The program instructions generate source data information from a file system database and request a number of sectors of data from the file system database.

Abstract: An apparatus and method for detecting a wobble signal read from an optical disc. The wobble signal detection apparatus comprises an analog/digital (A/D) converter for A/D-converting an analog wobble signal, read from the optical disc and then band pass filtered, a slope detector for detecting a slope of the A/D-converted wobble signal according to a variation thereof, and a wobble signal detector for detecting a peak point of the A/D-converted wobble signal using the detected wobble signal slope, and detecting/outputting a square-wave wobble signal with a high level or low level transition at the detected peak point. The slope detector calculates variations of data values of the A/D-converted wobble signal sampled within a predetermined period on the basis of predetermined different weights, accumulates the calculated values and detects the slope of the A/D-converted wobble signal on the basis of the accumulated value.

Abstract: An optical recording medium comprises a plurality of identifiers in association with address information, wherein: each identifier is provided on the optical recording medium; and each identifier comprises at least one of: a first pattern provided on the optical recording medium and representing a first code expressed by one bit; a second pattern provided on the optical recording medium and representing a second code expressed by one bit; and a third pattern provided on the optical recording medium and representing a third code expressed by one bit.

Abstract: A wobble signal detecting circuit for optical disc system includes at least a sample-and-hold circuit for carrying out sample-holding steps on each of first and second photoelectric signals, and a high range frequency limiting circuit for removing frequency components equal to, or higher than, a predetermined cut-off frequency from the first and second photoelectric signals. By selectively enabling either the sample-and-hold circuit or low range frequency limiting circuit depending on recording conditions during the period of recording information into an optical information recording medium, noise components which may unduly affect wobble signals can be removed efficiently irrespective of recording conditions.

Abstract: An information recording/reproducing apparatus irradiates a light beam on an optical disc on which pre-pits are formed, and performs recording and/or reproduction of information with respect to the optical disc according to a recording clock produced based on a wobble signal and a pre-pit signal. When recording information onto the optical disc having the pre-pits, a light beam is radiated to thereby extract the wobble signal and pre-pit signal. Then, according to the wobble signal and the pre-pit signal, a recording clock signal is produced, and information is recorded based on the recording clock signal. When producing a pre-pit signal, a push-pull signal is produced from the reflected light from the optical disc, and this signal is compared with a reference level to thereby detect a pre-pit. Here, when a pre-pit is not detected, the reference level is changed and the detection processing of the pre-pits is executed again.

Abstract: An optical disk device which reproduces address information embossed and formed on an optical disk. Return light of laser light is detected by a photodetector which is split into at least two components along the radial direction and signals representing the return light are output. Address information is reproduced by selectively switching between a summation signal and a difference signal between two signals. When there is a focus deviation, the summation signal of two signals is used to reproduce the address information and when the optical disk is tilted, the difference signal of two signals is used to reproduce the address information.

Abstract: An optical recording apparatus records information on a rewritable recording medium having a pre-recorded address guide by an external link method without performing complex calculations. Data is recorded on the rewritable optical recording medium on an individual block basis along the pre-recorded address guide, the block including a predetermined number of sectors each of which has a consecutively numbered sector address. A link part having a predetermined fixed length is recorded between adjacent blocks. The link part lacks an address so that the sector address shifts from an address indicated by the pre-recorded address guide by the length of said link part.

Abstract: An optical disc has an information recording portion. The information recording portion has a spiral of a groove, and land portions located between portions of the groove which neighbor each other as viewed in a disc radial direction. Auxiliary information used when an information signal is recorded on and reproduced from the groove is previously recorded on the land portions. The auxiliary information is represented by pre-pits provided in the land portions. The information recording portion is divided into a plurality of zones as viewed in the disc radial direction. In each of the zones, at least one of two sides of the groove wobbles at a fixed frequency in accordance with a constant angular velocity system. In each of the zones, phases of wobbles of respective neighboring portions of the groove are equal to each other.

Abstract: An optical disk apparatus for driving an optical disk on which a groove wobble corresponding to a signal acquired from frequency modulation of biphase modulated address information, and a mark for representing phase information placed inside the wobble are preformatted, and having the biphase bit count “a” (“a” is a natural number) between two of the adjacent marks, and the channel bit count “n” (“n” is a natural number) between two of the adjacent marks. The apparatus includes first clock signal production means for generating a first clock signal utilizing an “n” frequency multiple of the reproduction signal of the clock mark, wobble signal reproduction means for reproducing from the optical disk a wobble signal corresponding to the groove wobble, and frequency demodulation means for acquiring the address information by frequency demodulation of the wobble signal.

Abstract: An information reproducing apparatus includes a rotating portion to rotate an information recording medium on which information has been recorded by wobbling borders on both sides of a track with different phases; a beam irradiating portion for irradiating a beam spot on the track of the information recording medium; a photodetector for receiving a reflected beam of the beam spot from the information recording medium; a detector for detecting a composite waveform including waveforms on the borders on both sides from the received beam intensity of the photodetector; a phase change detector for detecting changes in the phase of wobbling waveforms on the borders on both sides from the composite waveform; and an information reproducer for reproducing information corresponding to detection result of the phase change detector by using a predetermined relation between phase changes and information.

Abstract: In a data storage system in which a sequence of data blocks is written onto a medium, appended data is distinguished by including in the first and subsequent appended data blocks an append point code uniquely identifying the location of the first appended data block. Where the data blocks have a running block number or frame number, the block or frame number of the first appended data block is stored as the append point code. This clearly identifies the most recent append point location which will aid in processes such as tracking calibration data integrity confirmation and track positioning.

Abstract: A recording apparatus, a recording method, and a recording medium, which allows a search operation based on a second segment information signal representing finely divided segments of a recording signal even in a player which can perform only a searching operation of a first segment information signal representing large segments of the recording signal. When a change of the second segment information signal of a signal to be recorded is detected, the first segment information signal being formed is updated and the first segment information signal is recorded together with an audio signal. That is, the second segment information signal of the signal to be recorded is converted into the first segment information signal and recorded together with the audio signal.

Abstract: An information playback apparatus is disclosed which can play back information with a high degree of accuracy. The information playback apparatus plays back the addresses from a recording medium on which a land address and a groove address are recorded at positions displaced from each other.

Abstract: In an optical or magnetic disc audio system, during conventional play the audio is decoded and played from the disc (RDISC) under the direction of a presentation control (PC) and the subcodes indicating time on the disc, track number and so forth are generated. Depending on the system hardware, for some speeds and directions (other than normal play) it may not be possible to decode real subcodes from the disc, and an emulator module (EMU) is switched in at these times. The emulator (EMU) plays a virtual disc (VDISC) using a timer (TIM) and the table of contents (TOC) from the real disc. While the audio is not replayed, the track and time listing display (DISP) is kept up to date, with a typical update for each second of real disc play time. As an extension to this feature, the emulator module (EMU) periodically generates seek commands for the read head in relation to the real disc (RDISC) such that, when normal playback is resumed, there is minimal delay in locating the chosen audio.

Abstract: During recording operations, decay processing is performed with regard to reflected light information signals (I1 and I2) during periods wherein the laser output is recording power which is comparatively high level, i.e., wherein data pits are being formed on the disk, and during recording operations, decay processing is not performed with regard to reflected light information signals during periods wherein the laser output is reproducing power which is comparatively low level, i.e., wherein the pits are not being formed on the disk. Accordingly, address information can be extracted in a stable manner while recording.

Abstract: An optical information recording medium according to the present invention includes at least one groove track and at least one land track allowing information to be recorded on or reproduced from the groove track and the land track, the groove track and the land track adjoining each other. The optical information recording medium further includes: an identification signal region including a pre-pit array, the pre-pit array indicating identification information concerning the groove track and the land track; and a servo control region disposed ahead of the identification signal region along the groove track and the land track, the servo control region including wobble pits positioned so as to shift to opposite sides of a center line of either the groove track or the land track.

Abstract: On an optical disk medium according to the present invention, address information is recorded along a wobbling track groove 2. The track groove 2 is made up of a plurality of unit sections 22, 23. Each of these unit sections 22, 23 has side faces that are displaced periodically in a disk radial direction. This displacement oscillates at a single period in a tracking direction. However, the displacement pattern differs depending on “each bit of address information (subdivided information)” allocated to each of the unit sections 22, 23.

Abstract: A disk player for recording or reproducing recording information to a recording disk by emitting a light beam onto the recording disk. The recording disk has a recording track for recording the recording information, a guide track for guiding the light beam to the recording track, and a prepit which is pre-formed on the guiding track and which serves as control information for controlling a recording operation or a reproduction operation of the disk player.

Abstract: A recording apparatus includes a gate signal generator for generating a gate signal in accordance with the data signal; a pre-pit signal generator for generating a pre-pit signal from a signal read from the recording medium; a gate circuit for generating a pre-pit pulse train by allowing the pre-pit signal to pass therethrough in response to the gate signal; a pulse extractor for extracting pulses of predetermined waveform from the pre-pit pulse train; and a synchronization signal generator for generating a recording synchronization signal based on the pulses of predetermined waveform.

Abstract: The present invention discloses a disk player for recording information on a disk and/or reproducing recorded information thereon. The disk player includes a wobble detection unit for detecting a wobble signal corresponding to a wobbling pattern formed along a track of the disk; and an information processing unit for detecting a pre-pit signal recorded on the disk using the wobble signal output from the wobble detection unit and a clock signal obtained by multiplying the wobble signal a predetermined number of times, and for processing the information recorded on the disk or the information to be recorded thereon according to the detected pre-pit signal. Since the detection of a synchronization signal can be performed more precisely, this disk player can reduce error in the recording and reproduction of data.

Abstract: For recording data on and reproducing data from an optical disk of a single spiral land/groove configuration, a header detector detects header regions on the optical disk, a PID error detector judges whether the address information read from the header regions is erroneous, using error detection codes, and detects the number of errors per sector. An error count comparator compares the number of errors per sector with a predetermined value, and a state judging circuit identifies the state of the optical disk device by causing transition to a higher or lower state according to the output of the error count comparator. The recording and reproduction are controlled according to the state thus identified.

Abstract: The present invention is aimed at providing an optical disk, an optical disk device, and an optical disk reproduction method, for allowing for stable and efficient reading of address information. The optical disk includes a plurality of tracks each divided into a plurality of recording sectors. Each of the recording sectors includes a header region. The header region includes address information for identifying the position of the corresponding recording sector and address synchronous information for identifying the recording position of the address information for bit synchronization. The address information has been modulated using a run length limit code of a maximum inversion interval of Tmax bits (Tmax is a natural number), and the address synchronous information includes two patterns of which inversion interval is (Tmax+3) bits or more, so that the reproduced signal of the address synchronous information is distinguished from the reproduced signal of other information.

Abstract: A DVD-RAM disk reproduction apparatus for reducing an error during detection of ID data, which includes a first operational amplifier for obtaining a sum signal resulting from the addition of four picked-up signals picked up by divided-by-four photodiodes from a DVD-RAM disk having a header region and a recording region, second and third operational amplifiers for respectively obtaining two sum signals corresponding to the upper and lower regions of the header region resulting from the addition of the first and second picked-up signals and the third and fourth picked-up signals, respectively, a fourth operational amplifier for obtaining a difference signal between the two sum signals, a header region detector for detecting upper and lower header region signals corresponding to the upper header region and the lower header region based on the difference signal, and detecting a header region signal corresponding to a header region by logically summing the two detected signals, a first multiplexer for selecting o

Abstract: A reproduction apparatus includes a signal input section for receiving an input signal, an Input signal determination section for determining a type of the input signal based on whether or not a first synchronization signal among a series of N synchronization signal exists within a predetermined search area of the input signal (N is an integer equal to or greater than 2); and a signal processing section for performing a signal processing process selected according to the type of the input signal on the Input signal.

Abstract: An information record and playback apparatus configured to perform record and playback operations of an optical disk which is provided with data recording tracks having a surface wobbled at a predetermined frequency and a plurality of prepits formed with a predetermined phase relation to the position for data recording. The apparatus includes at least a demodulation circuit which operates for a predetermined error flag be indicated at the position of the assumed LPP data bit, when the error pattern is detected to be other than ‘1’ or ‘0’, that may be caused, for example, by noise. Erasure correction with the Reed-Solomon code therefore becomes feasible using the error flag. This achieves error correction of a number of errors even using fewer added data, thereby offering advantages in increasing efficiency in the error correction.

Abstract: A pre-pit signal detecting apparatus is used in an information recording apparatus for recording record information onto a record medium on which record control information for controlling a recording operation is recorded in advance by forming a pre-pit on the record medium, and detects a pre-pit signal corresponding to the pre-pit when the information recording apparatus records the record information onto the record medium.

Abstract: An apparatus for detecting and restoring physical identification data (PID) which is the physical position information of sectors arranged on an optical disk, is used in an optical disk recording/reproducing system having a radio frequency amplification unit, includes a pattern detector for outputting an address mark detection signal and a PID pattern upon detecting an AM pattern, and the PID pattern from an eight-to-fourteen modulation (EFM) data stream in the enable section of input signals, a PID error detecting unit for detecting the generation or non-generation of an error by decoding the received PID pattern, and outputting a PID error signal, a sector counting unit for counting the remaining size of a corresponding sector and outputting a counted value as a channel bit clock counting value, a PID window generator for receiving the channel bit clock counting value from the sector counting unit, generating a window signal for PID detection when the counting of a sector is concluded, and outputting the wi

Abstract: According to the present invention, in a disk-shaped recording medium such as an optical disk and the like, a reference clock with a frequency corresponding to a reproduction frequency of data reproduced from a data recording region is divided in accordance with a ratio between a record density of a header region where pre-formatted data including a sector mark for indicating a leading position of a sector is recorded, and a recording density of a data recording region subsequent to the header region, so as to produce a sampling clock. Then, by use of thus-produced sampling clock, the sector mark is detected. This structure enables, even if the header region has a recording density different from the recording density of the data region, to use a sector mark detector having the same structure as of a sector mark detector which is employed in the case where the header region has the same recording density as that of the data region and therefore a reference clock is used.

Abstract: A recording time point setting method and apparatus are provided. The recording time point setting method is a method of setting a recording time point for recording an information piece into one of a plurality of predetermined areas on a recording medium on the basis of a plurality of marks. The marks are pre-recorded on the recording medium at predetermined intervals. The locations of the marks correspond to the locations of the predetermined areas, respectively. The locations of the predetermined areas are predetermined on the basis of a time length of the information piece. In this method, firstly, at least one of the marks is detected. Then, an expectation signal is generated on the basis of the time length of the information piece, and then, a time point at which an output of the expectation signal is started is synchronized with a time point at which the at least one of the marks is detected.

Abstract: An object of this invention is to provide a method for processing signals for an optical disc device and an optical disc device for immediately determining the on-track state of a main beam light impinging on an optical disc including land areas on which information is recorded, said optical disc being track-formatted to have a double spiral structure. In recording or reproducing information on or from the land areas while track-controlling a first reflected light (MB) based on a second reflect light (SB1) and a third reflect light (SB2), the phases of a sum signal (SUM) and a difference signal (DIFF) between a first push-pull signal (PP1) obtained from an output from a first split photo conductor (21) and a second push-pull signal (PP2) obtained from an output from a second split photo conductor (23) are compared to determine from the mutual phase relationship which land area is providing the first reflected light (MB).

Abstract: A magneto-optical record medium and a reproducing apparatus for the same allow data reproduction having good characteristics by a simple structure. The magneto-optical record medium includes a plurality of first grooves (3) each having sidewalls, at least one of which is wobbled in accordance with address information; an address mark (21) formed by changing a width of a land located between second grooves connected to the first grooves; and third grooves wobbled cyclically, formed in a data portion magnetically storing data and connected to the second grooves. The reproducing apparatus reproduces the data from the magneto-optical record medium.

Abstract: An optical disc having a data area in which information signals are recorded, a lead-in area and a lead-out area provided before and after the data area, and a program memory area for temporarily storing address information necessary for additionally writing information signals. A subcode Q of the lead-in area or a subcode Q of the program memory area is provided with identification information for identifying these subcodes Q. For example, the identification information is provided at least in one of address (ADR), track number (TNO), and zero (ZERO) constituting the subcode Q of the program memory area or the lead-in area. Thus, it is possible to discriminate the subcode Q of the program memory area and the subcode Q of the lead-in area securely and instantaneously.

Abstract: In reproducing a recording medium having a main data area for recording main data, an auxiliary data area for recording auxiliary data such as image data and text data corresponding to the main data, a first control area for controlling the main data area, and a second control area for controlling the auxiliary data, the auxiliary data is reproduced in a predetermined timed relation with the main data based on synchronization information recorded in the second control area.

Abstract: Disclosed is a disc player for obtaining a read signal from an optical disc having sectors including land and groove tracks and ID regions, preformatted at given angular spatial intervals, which demarcate the sectors and are segmented, in the track extending direction, into two regions, each segmented region including a plural number of recording regions and non-recording regions, which are alternately and radially arrayed while being radially shifted by approximately half a track pitch from the tracks of the sectors adjacent to the segmented regions, each recording region containing record position information recorded therein having predetermined time durations.