Abstract: Aspects of the disclosure pertain to a system and method for providing dynamic y-buffer size adjustment for retained sector reprocessing (RSR). The system and method implement dynamic y-buffer size adjustment for RSR for promoting improved Sector Failure Rate (SFR) performance of the system. The system is a read channel system.

Abstract: The method adapted for a disc burner for sensing/computing the maximum allowable capacity of a disc for overburn purpose where an accurate capacity of the disc based on the outermost-edge wobble signal is obtained, resulting in more data written on the disc with an amount of the data smaller than the physically-recordable maximum capacity of the disc and decreasing the failure rate of data overburning.

Abstract: Techniques are described herein that synchronize media streams using time signal(s) from an independent time source. An independent time source is a time source that is independent from (i.e., that is not connected to) an asynchronous data network via which the media streams are transferred. In accordance with the techniques described herein, media server(s) transfer the media streams to client(s) via an asynchronous data network. The independent time source provides the time signal(s) to the media server(s) and/or the client(s). If the time signal(s) are provided to the media server(s), the media server(s) may provide timing information that is based on the timing signal(s) to the client(s). The client(s) use the timing information from the media server(s) and/or the timing signal(s) from the timing source to synchronize the media streams.

Abstract: A reading apparatus and method for reading data from a digital versatile disc includes a specification section configured to specify a predetermined position of content. A controller generates information indicating a predetermined portion from a position specified by the specification section. A storage section reads the predetermined portion from the digital versatile disc on the basis of the information generated by the generation section and stores the predetermined portion on a storage medium. A reading controller controls reading of data from the storage medium and the digital versatile disc.

Abstract: The directory information on a file system recorded on an optical disc is cached onto a hard disk as a directory table. When accessing a file on the optical disc, a processor references the directory table so as to obtain information related to a position, on the disc medium, where the file to be accessed is located, without accessing the directory information on the optical disc. A disc I/O controller moves a pickup unit to the location indicated by the positional information on the file to be accessed and reads the data on the file. The pickup unit is used to detect signals from the optical disc.

Abstract: A buffer control system for generating a buffered signal having reduced buffer delay time between playback of tracks includes a controller module for providing an end target and for selection of a servo data signal corresponding to a desired track; a compare circuit coupled to the servo data signal for comparing a timestamp of the servo data signal to the end target, and asserting an end match signal when the timestamp of the servo data signal matches the end target; and a data buffering unit for storing the servo data signal as stored data to fill a capacity of an internal memory, and streaming out the buffered signal from the stored data in the internal memory when the capacity has reached a predetermined level; wherein the controller module is for updating selection of the servo data signal according to a next desired track upon assertion of the end match signal.

Abstract: A recording apparatus capable of multiplexing video data and audio data and recording the video data and audio data in multiple record units as one file on a recording medium includes a data receiving unit, a recording instruction receiving unit, a packet generating unit, a recording unit, and a control unit. The control unit controls the packet generating unit and the recording unit so as to record data embedded with padding data in a section from the trailing end of valid data to the trailing end of the block including the trailing end of the valid data at stop of the recording and to record data embedded with the padding data in a section from the trailing end of the block to the trailing end of the packet including the trailing end of the block at restart of the recording after the recording is stopped.

Abstract: An optical disk apparatus for enabling to insert a multi-layered optical disk therein, which has plural numbers of recording layers, comprising: a spindle motor 42; an optical pickup 2; and a system controller 100 for controlling the optical pickup to move into a radial direction of the optical disk, as well as, for controlling the optical pickup so that a light-beam irradiated therefrom is focused upon either one of the plural numbers of recording layers of the optical disk, wherein when it is determined that the target layer to be accessed lies on a layer different from that, upon which the optical pickup focuses the light-beam at present, the light-beam irradiated from the optical pickup is shifted to the target layer, after being moved into a radial direction of said optical disk on the layer, upon which the light-beam irradiated therefrom is focused at present, up to an information recording area where the information of the target layer is recoded.

Abstract: An information recording/reproducing apparatus including an optical pickup unit for generating an RF signal performs signal processing to acquire, at a restart of recording after a halt of recording, a data ID to be used as a reference for specifying a recording restart position in the recording medium based on the RF signal. The signal processing includes reproduced signal generation processing to generate a reproduced signal based on the RF signal, and data ID acquisition determination processing to determine, at the restart of recording after the halt of recording, whether or not the data ID has been properly acquired, based on the reproduced signal. If it is determined in the data ID acquisition determination step that the data ID has not been properly acquired, a reproduction parameter to be used for generating the reproduced signal in the reproduced signal generation step is adjusted.

Abstract: An optical disk apparatus according to the present invention includes a spindle motor that rotates an optical disk on whose information recording surface a plurality of addresses is recorded, an optical pickup that records/reproduces an information signal on/from the information recording surface of the optical disk rotated by the spindle motor, an strobe light-emitting unit that irradiates a label surface of the optical disk with light, and a control unit that causes the strobe light-emitting unit to emit light based on an address selected from the plurality of addresses as a reference address and a reference signal readable from the optical disk.

Abstract: A clock generation circuit is provided that multiplies an input signal of a specific frequency by a specific multiplication factor and generates an output clock signal. The clock generation circuit includes a PLL circuit that multiplies the input signal and generates the output clock signal, and a correction circuit that changes the multiplication factor of the PLL circuit. The correction circuit changes the PLL circuit multiplication factor by increasing or decreasing the specific multiplication factor, the change being performed only during a correction interval for each correction cycle, the correction cycle being longer than one cycle of the input signal, and being performed such that a time difference between an input synchronizing signal synchronized with the input signal and an output synchronizing signal synchronized with the output clock signal is reduced. The PLL circuit multiplies the input signal by the changed multiplication factor during the correction interval.

Abstract: This invention provides an optical storage device for recording a plurality of data onto an optical storage medium. If recording interrupted, the optical storage device generates a data-interrupted address, and re-connects the interrupted data with a data re-connecting physical address. The optical storage device comprises a physical addressing module, a record-interrupt generator, a data recording controller, a data-interrupt address generator and a data-reconnecting physical address generator. The physical addressing module provides a reference physical address for recording data onto the optical storage medium. When detecting the interrupt of data recording, the data-interrupt address generator generates the address of the interrupted data. According to the address of the interrupted data, the data-reconnecting physical address generator generates a data-reconnecting physical address.

Abstract: There is provided an optical disc recording/reproducing apparatus which can reduce the chip size using the high-miniaturization process and can enhance the detection accuracy. A signal which is obtained by amplitude-adjusting a header region in a reproduced signal detected by an optical pickup (1) is digitized, and peak detection or bottom detection from the reproduced signal in each of a first section and a second section in the header region is performed by detection circuits (9) to (12), respectively. Then, amplitude data in the first section and the second section are obtained by subtracters (13) and (14) from the detected values in the respective detection circuits. A difference in amplitude between the first section and the second section in the header region is obtained by a subtracter (15) based on the amplitude data, and the amplitude difference is outputted as an off-track error signal.

Abstract: An apparatus and a method for generating ATIP data is provided. The apparatus generates ATIP data from a wobble signal of a re-writable compact disc. The apparatus includes a frequency demodulator for demodulating the wobble signal to generate an original ATIP data signal; an ATIP clock generating circuit for generating an ATIP clock signal based on the wobble signal; and a data generating circuit, coupled to the frequency demodulator and the ATIP clock generating circuit, for generating the ATIP data based on the number of measurement periods for which the original ATIP data signal is at a first logic level during one period of the ATIP clock signal. This apparatus uses this number and the bi-phase rule to precisely generate ATIP data.

Abstract: This optical disk device includes a read means which reads data from an optical disk upon which data is recorded at a variable bit rate for each sector. Moreover, this optical disk device includes a buffer memory which sequentially stores data which has been read by the read means, and a replay means which sequentially reads out and decodes data stored in the buffer memory, and replays that data. Furthermore, this optical disk device includes a control means which, when a command for special replay is issued, calculates the address of the sector currently being decoded by the replay means based upon the address of the sector currently being read by the read means, and upon the amount of data stored in the buffer memory. And the control means commands the read means to read out, from the optical disk, a sector to be jumped to.

Abstract: A method of controlling recording of an optical disc device and an optical disc device using the method. The optical disc device performs recording of data on a labeled surface of the optical disc. The device includes a buffer memory, a record unit and a controller. The buffer memory stores data and the record unit records data on the labeled surface of the optical disc from the buffer memory. The controller controls the record unit such that when a recording error occurs, the recording is stopped and when the error is corrected, data is recorded from a stopped position.

Abstract: An enhanced write splice for optical recording channels is disclosed. Optical control circuitry locks to previously-written data and determines the estimated write splice location. A training sequence is written to the optical medium at a location based on the estimated write splice location. The phase offset is then estimated by reading the training sequence. A new write splice location may then be calculated compensating for the phase offset estimate. Finally, the new data to be spliced may be written or overwritten to the channel at the new write splice location.

Abstract: A playback device for playback of a media stream stored on a storage medium, the device includes a controller for controlling the reading, buffering and playback of the media stream. During playback, a buffer is filled by a reader and emptied by a playback unit. At each buffer, filling a buffer refilling time, i.e., the moment when the buffer will be empty and thus has to be refilled, is calculated. After each buffer filling, the storage medium can change to standby mode till buffer refilling is to occur. Thus, power consumption by the storage medium is minimized. The buffer refilling time depends on the total consumption time and the buffer filling period. The total consumption time is determined depending on playback mode control information. The buffer filling period is calculated depending on information about the retrieval of the media stream or an estimation of the buffer filling period is made.

Abstract: A write strategy setting apparatus applied in an optical disc drive includes a storage unit, an error calculator, and a write strategy controller. The storage unit stores an initial write strategy including a plurality of write strategy parameter sets corresponding to a plurality of data set types; the error calculator calculates an error value set for each data set type generated by the optical disc drive utilizing a corresponding write strategy parameter set in the initial write strategy, and stores the calculated error value set into the storage unit to thereby overwrite the write strategy parameter set; and the write strategy controller determines a modified write strategy by referring to a plurality of error value sets stored in the storage unit and the initial write strategy, and then storing the modified write strategy into the storage unit.

Abstract: A system for generating an output signal indicating a specific area on an optical disc is disclosed. The system includes: a detecting circuit, a header signal generator, a protection circuit, a counter and an output signal generator. The detecting circuit detects pre-recorded address information on the optical disc to generate a detection signal. The header signal generator detects headers on the optical disc to generate a header signal. The protection circuit computes a first counter value and reloads the first counter value according to the detection signal and the header signal, wherein the protection circuit does not reload the first counter value twice successively due to the header signal. The counter computes a second counter value and reloads the second counter value according to the first counter value. The output signal generator generates the output signal according to the first counter value.

Abstract: Herein disclosed a phase difference detection apparatus for detecting a phase difference between a first signal and a second signal, which may include a waveform equalization section configured to input the first and second signals as a target waveform and an input waveform, respectively, to perform a waveform equalization process using a FIR filter so that the input waveform may coincide with the target waveform; and a phase difference detection section configured to perform a predetermined calculation based on predetermined tap coefficients of the FIR filter in the waveform equalization section to calculate an asymmetric component of the tap coefficients of the FIR filter thereby to detect the phase difference between the first and second signals.

Abstract: A method and apparatus for recording data at specific locations on a DVD includes selectively detecting the occurrence of wobble sync during a window computed from previous occurrences of wobble sync and eight-to-fourteen modulation sync. The method and apparatus also uses a phase-locked loop to recover the wobble signal, including wobble sync, and computes phase drift between wobble sync and eight-to-fourteen modulation sync and applies a compensation profile, compatible with a read clock phase-locked loop, to the wobble phase-locked loop.

Abstract: An enhanced write splice for optical recording channels is disclosed. Optical control circuitry locks to previously-written data and determines the estimated write splice location. A training sequence is written to the optical medium at a location based on the estimated write splice location. The phase offset is then estimated by reading the training sequence. A new write splice location may then be calculated compensating for the phase offset estimate. Finally, the new data to be spliced may be written or overwritten to the channel at the new write splice location.

Abstract: A data recording method is disclosed which includes the steps of: firstly recording audio data onto a temporary storage medium following retrieval of the audio data from an external storage medium in response to an audio data import request; detecting whether a leading frame of the audio data held on the temporary storage medium references a preceding frame; and secondly recording the audio data held on the temporary storage medium to a storage medium in accordance with an outcome of the detecting step.

Abstract: A method for identifying an optical disk according to a radio frequency integration filtering signal includes the steps of: moving an optical head to an initial position; rotating the optical disk and making focus, moving the optical head in a direction toward an inner ring until the optical head is moved to a home position or the focus fails, reading the radio frequency integration filtering signal, and recording a maximum and a minimum thereof when the optical head is being moved; stopping the optical head and determining whether a difference between the maximum and the minimum is greater than a predetermined threshold value; setting the optical disk as a second type of disk if the difference is greater than the predetermined threshold value; and setting the optical disk as a first type of disk if the difference is smaller than or equal to the predetermined threshold value.

Abstract: An apparatus for and a method of detecting a wobble signal in accordance with a time shift includes comparing a basic wobble signal with reference levels to detect pulses representing the time shift in an analog fashion, and digitally determining a code value for the basic wobble signal on the basis of the widths of the pulses using a channel clock signal and a wobble clock signal. The determined code value is accumulated and serves as a basis on which final wobble data is produced.

Abstract: An optical recording device records data on an optical storage medium. The device generates a data-interrupted address and reconnects the interrupted data from a data-reconnecting address so as to enable further correct reading of the interrupted data. The device comprises an addressing module for providing a reference address on the storage medium as a reference address; a recording-interrupted generator for detecting a recording-interrupted condition and generating a recording-interrupted signal; a data recording module for recording and suspending recording the data according to the recording-interrupted signal, and reconnecting the data according to a data-reconnecting address and the reference address; a data-interrupted address generator for generating the data-interrupted address; a data-reconnecting address generator for generating the data-reconnecting address.

Abstract: A reading unit for reading data from a digital data carrier, the reading unit comprising: a reading head including a sensor for sensing data from the data carrier and generating a sensor signal indicative for the sensed data; head positioning apparatus for positioning the head relative to the data carrier in response to a head positioning control signal; a head positioning controller for receiving the sensed data and being operable in accordance with a stored instruction set to process the sensed data to generate the head positioning control signal; and a data decoder for decoding the sensed data to form a digital output signal.

Abstract: A disc playing method and related system without interruption is disclosed. First, the data blocks on a disc (such as a DVD) is previewed without playing. Next, the error ratio of the data block is determined. If the error ratio of the data block exceeds a predetermined threshold, the address of the data block is recorded in an error data table. Finally, the data blocks not recorded in the error data table are played.

Abstract: An apparatus for scanning a track on a record carrier has a head for scanning the track and generating a read signal. The tilt between the head and the record carrier (11) is compensated via a tilt servo loop. Thereto the head is provided with tilt compensating actuators (42). A measure of the tilt is jitter in the read signal generated by a front end (43) and filter (44). A wobble generator (40) provides a wobble signal to the actuators and to an input of multiplier (45) for synchronous detection of the jitter. The output of the multiplier (45) is coupled to a low pass filter (46) for generating a tilt error signal coupled to a tilt controller (47) for generating a tilt control signal.

Abstract: The invention provides a data recording device comprising: an interval counter; an ? counter; and a segment counter, wherein the interval counter and the ? counter operate with a clock having a constant frequency which is independent of clock information, the interval counter is reset when division information is detected and, also, is reset and activates the ? counter when it reaches a count value corresponding to a segment length, the ? counter is reset when the division information is detected and, also, is reset and increments the count value of the segment counter when it reaches a count value corresponding to a predetermined length smaller than the segment length, and the segment counter increments its count value when the division information is detected and outputs a writing inhibition signal when it reaches a count value corresponding to the frame length.

Abstract: This optical disk device includes a read means which reads data from an optical disk upon which data is recorded at a variable bit rate for each sector. Moreover, this optical disk device includes a buffer memory which sequentially stores data which has been read by the read means, and a replay means which sequentially reads out and decodes data stored in the buffer memory, and replays that data. Furthermore, this optical disk device includes a control means which, when a command for special replay is issued, calculates the address of the sector currently being decoded by the replay means based upon the address of the sector currently being read by the read means, and upon the amount of data stored in the buffer memory. And the control means commands the read means to read out, from the optical disk, a sector to be jumped to.

Abstract: A method for recording address information to an optical disc (5) by forming a wobbled groove is provided. The method includes steps S1 to S3. In step S1, there is generated address information composed of a sync signal, address data and an error correction code for the address data. In step S2, a carrier signal is multiplied by the address information to generate a phase modulation signal. In step S3, there is formed on the optical disc (5) a spiral groove wobbled adaptively to the phase modulation signal.

Abstract: A detector for detecting information carried by a wobble signal having a sawtooth-like shape with a base frequency of fwob. The detector includes a first band-pass filter having a center frequency close to 2*fwob for filtering the wobble signal and generating a first filtered signal, a second band-pass filter having the center frequency close to fwob for filtering the wobble signal and generating a second filtered signal, first and second comparators for respectively comparing the first and second filtered signal with a reference voltage and generating first and second compared signals, a delay unit for delaying the second compared signal by a time period, and then outputting a delayed signal, and a sampling unit for sampling the first compared signal using the delayed signal as a sampling clock, and for outputting a sampled value representing the information carried by the sawtooth wobble.

Abstract: An information recording/reproducing apparatus and information reproducing method records information data, regardless of an external disturbance. According to a demodulated timing pulse, a synchronization signal and address data representative of an address is demodulated from a readout signal. An error correction process carried out on the address data obtains corrected address data. A determination is made if the corrected address data is a correct address. When the synchronization signal has a period equal to a predetermined period, a synchronization process is executed to place the demodulated timing pulse in synchronism with the synchronization signal, wherein, when the corrected address data is determined as a correct address, then the re-synchronization process is put into stand-by until the corrected address data is determined as an incorrect address.

Abstract: A link writing method for a recordable or rewritable compact disk includes recording a writing interruption address and enabling a succeeding writing process after the writing interruption. Enabling a succeeding writing process includes searching the linking area and enabling a start writing signal and activating a laser power. The method can link a succeeding writing area with a previously written interrupted area with sufficient accuracy to allow the data frame to be successfully processed by error correction within the host drive. The linking area may be positioned by counting the values of the interrupted block, the interrupted data frame, and the interrupted bit count or by detecting a blank area. Other techniques for positioning the linking area include detecting an unwritten area having a length greater than a maximum or writing a characteristic pattern after an interruption.

Abstract: This invention provides an optical storage device for recording a plurality of data onto an optical storage medium. If recording interrupted, the optical storage device generates a data-interrupted address, and re-connects the interrupted data with a data re-connecting physical address. The optical storage device comprises a physical addressing module, a record-interrupt generator, a data recording controller, a data-interrupt address generator, and a data-reconnecting physical address generator. The physical addressing module provides a reference physical address for recording data onto the optical storage medium. When detecting the interrupt of data recording, the data-interrupt address generator generates the address of the interrupted data. According to the address of the interrupted data, the data-reconnecting physical address generator generates a data-reconnecting physical address.

Abstract: A method and apparatus for reading an index mark pattern. The pattern may be formed on an optical disc medium. The optical disc medium may include a set of data arranged in a data field, and an index mark pattern for identifying a relative location of the data field.

Abstract: A link writing method for a recordable or rewritable compact disk includes recording a writing interruption address and enabling a succeeding writing process after the writing interruption. Enabling a succeeding writing process includes searching the linking area and enabling a start writing signal and activating a laser power. The method can link a succeeding writing area with a previously written interrupted area with sufficient accuracy to allow the data frame to be successfully processed by error correction within the host drive. The linking area may be positioned by counting the values of the interrupted block, the interrupted data frame, and the interrupted bit count or by detecting a blank area. Other techniques for positioning the linking area include detecting an unwritten area having a length greater than a maximum or writing a characteristic pattern after an interruption.

Abstract: An apparatus and method detecting synchronization of address in pre-groove (ADIP), allowing an optical storage device to write data to an accurate location of a disc includes a bit synchronization detecting unit and a word synchronization detecting unit. The bit synchronization detecting unit determines synchronization of bits of the ADIP to be in a bit synchronization locked state when synchronization of raw bits is detected within a bit synchronization window having a first predetermined period a first predetermined number of consecutive times. The word synchronization detecting unit determines synchronization of words of the ADIP to be in a word synchronization locked state when synchronization of raw words is detected within a word synchronization window having a second predetermined period the first predetermined number of consecutive times.

Abstract: A control circuit for an optical disk drive includes a frequency detector, a phase detector, a low pass filter, a voltage-controlled oscillator (VCO), and a controller. The frequency detector and the phase detector both receive an eight-to-fourteen modulation (EFM) signal and a data phase-locked loop (DPLL) signal. The controller can calculate a target frequency and control the VCO to output the DPLL signal according to the target frequency. During a non-seek mode, the VCO outputs the DPLL signal according to output of the frequency detector, phase detector, and low pass filter. During a seek mode or when spindle speed of the optical disk drive changes, the VCO outputs the DPLL signal according to the target frequency. The controller further outputs charge pump currents for the frequency detector and the phase detector and sets an RF equalizer signal and a differential phase detector (DPD) equalizer signal according to the target frequency.

Abstract: A method for recording address information to an optical disc (5) by forming a wobbled groove is provided. The method includes steps S1 to S3. In step S1, there is generated address information composed of a sync signal, address data and an error correction code for the address data. In step S2, a carrier signal is multiplied by the address information to generate a phase modulation signal. In step S3, there is formed on the optical disc (5) a spiral groove wobbled adaptively to the phase modulation signal.

Abstract: A controller for an optical disk drive includes a modulator configured to modulate a record data to be recorded on a optical disk based on a record clock that is a reference clock in recording, and to generate a modulation data and an address information of the modulation data. A prepit decoder is configured to generate a prepit clock from a prepit signal detected from the optical disk, and a decision circuit is configured to determine whether or not recording in accordance with a standard is performed, from phase characteristic based on the address information and the prepit clock, and to control a frequency of the record clock.

Abstract: An optical disc drive includes: a motor for rotating an optical disc thereon; a photoelectric transducer for converting a light beam, reflected from or transmitted through the disc, into an electric signal; a clock sync signal reader for extracting and outputting a read signal, representing a clock synchronization mark, from the electric signal; a clock generator for generating a clock signal having a variable frequency; a phase locking controller for controlling the clock generator to synchronize the clock signal in phase with the output signal of the clock sync signal reader; and a mechanism for displacing a light beam spot toward a target track on the disc. During a seek operation of displacing the light beam spot toward the target track, the clock generator is controlled to obtain a frequency to be expected on the target track and output a clock signal having the expected frequency.

Abstract: The present invention relates to a recording apparatus for improving operability of a DVD camcorder that performs recording in a video format. When an instruction for starting recording is given at a time T11 and then an instruction for stopping the recording is given at a time T12, a DVD camcorder is brought into a pause state at the time T12. An address and the like of an optical disk at that time are stored in a recording RAM. When an instruction for resuming recording is given at a time T13, the address stored in the recording RAM is read, and rerecording is started at a position on the optical disk which position corresponds to the address. The present invention is applicable to DVD camcorders.

Abstract: A phase difference detection circuit (270) and a gain adjusting circuit (280) are provided in an optical disc recording apparatus (200). When the phase difference detection circuit detects a phase difference between an ATIP synchronization signal and a recording synchronization signal, this phase difference detection circuit activates an internal counter (271). Then, when phase difference information including a result of a counting operation performed by the internal counter is outputted from the phase difference detection circuit to the gain adjusting circuit, the gain adjusting circuit suitably adjust the frequency division ratio of a (1/N)-frequency-divider (242) according to the received phase difference information. Thus, the phase of a recording clock signal to be supplied from a PLL circuit (240) to a data encoder (260) through a frequency divider (250) is controlled.

Abstract: In the CAV recording, it is necessary to vary the recording-system clock frequency in accordance with movement of a recording position, and conventionally a signal generated by multiplying a wobble signal is used as the recording-system clock. However, since the wobble signal is easily susceptible to influences of a disk and a pick-up and its quality is prone to be deteriorated by an influence of a large amount of light at the time of recording etc., it is difficult to maintain jitters of the recording-system clock to a sufficiently low value. To resolve this problem, instead of generating a recording-system clock signal from the wobble signal that is susceptible to noise, a necessary recording-system clock frequency is calculated from the address information that has been modulated into the wobble signal and recorded therein, and a signal of this frequency is generated from a stable reference signal source, such as a quartz oscillator, by a synthesizer method and used as the recording-system clock.

Abstract: An information recording apparatus includes: a unit for applying a predetermined processing to record information divided into error correction units and generating processed record information including a plurality of record units; and a unit for recording the processed record information on an information record medium; a unit for recording, after the recording of the processed record information, predetermined dummy information of an information amount corresponding for the plurality of record units, on the information record medium, subsequent to the processed record information recorded.

Abstract: An optical disc includes a plurality of lands and grooves alternately arranged in a radial direction of the optical disc, each land wobbling in the radial direction and recording a header recording part for holding address information, there being a difference in elevation between each land and each groove, each grove having a data recording part for storing data, wherein the header recording parts offset alternately for respective lands in the radial direction, the data recording part in the groove and the header recording part in the land are arranged offset in a circumferential direction of the optical disc, and the header recording part in each land enables the same address information to be reproduced for two groove at both sides of each land.

Abstract: The sector synchronism of a timing generation section for generating data recording/reproducing timing is corrected at the address-mark detection timing of an address-mark detection section. Moreover, even if only one piece of address information having no error is not reproduced in the sector concerned, when at least one piece of address information having no error is reproduced in any of a predetermined number of sectors preceding the subject sector and at least one address mark is detected in the subject sector, the data recording/reproducing is permitted, and thus, the data is recorded/reproduced at a high speed and a high reliability even if an error rate of a physical address is deteriorated.