Abstract: According to the present invention, it is intended that the recording can be executed normally even against small vibrations to which a servo error signal detecting circuit cannot respond. A recording apparatus according to the present invention includes an optical head (12) for receiving a reflected laser beam (LREF) obtained when a laser beam (LIRR) is irradiated on a CD-R (10). This recording apparatus further includes a gate circuit (31) to which an output signal (SRD) of the optical head (12) is supplied and a level comparing circuit (34) for comparing a value of an output signal (DTAU) of this gate circuit (31) with a predetermined reference value (DTH). Upon recording, the gate circuit (31) is controlled in such a manner that a signal of a predetermined period ts may be outputted from the output signal (SRD) supplied from the optical head (12) to the gate circuit (31) as the output signal (DTAU).

Abstract: A track jump method for an optical recording/reproducing medium is provided. In the track jump method, once a track jump command is input, a track jump operation is held until a falling edge of a header mask signal is detected. The track jump starts at the falling edge of the header mask signal and ends before a rising edge of the header mask signal so that a TZC signal is not influenced by a header during the track jump. Therefore, the track jump can be exactly and stably performed. In particular, when the track jump command is input, a PLL of a wobble signal is inhibited, and a PLL-wobble signal is held to a previous value obtained before the track jump is performed, during the track jump, or a header mask signal is generated using a read channel signal which is not influenced by a wobble period, until a wobble signal becomes stable after a trackjump. During a normal servo, a header mask signal is generated using a PLL-wobble signal to mask a header area.

Abstract: A playback apparatus for reproducing data recorded on a disk medium by using an optical pickup, the playback apparatus comprising: RF signal generating means, data signal generating means, defect signal generating means, focus error signal generating means, focus servo control means, tracking error signal generating means, tracking servo control means, monitoring means, and defect period processing control means for controlling the focus servo control means and the tracking servo control means, wherein the focus servo control means and the tracking servo control means perform defect period processing when a result of the monitoring by the monitoring means indicates the defect period.

Abstract: The present invention realizes stable focus entry control even in the case where a wideband focus error signal is used with which the focus error signal sensitivity and the level in the vicinity of a focus point vary depending on a light path length. A second focus error signal having a wide range is used, causing an objective lens to approach a disk while maintaining a predetermined rate of change with respect to time, and, during approach, a transition to focus servo is performed by detecting the focus position according to the first focus error signal.

Abstract: There provided an optical disk recording/reproducing method and an apparatus thereof capable of constantly forming an optimum mark region while appropriately correcting recording conditions. A sample hold circuit 6 detects and holds the level of a TPP signal to output a state monitoring signal. A reference level setting portion 8 holds the level of the state monitoring signal at which an optimum recording state is obtained and outputs a reference level signal. A recording state determining portion 7 outputs a record shortage signal and a record surplus signal based on the result of comparison between the reference level signal and the state monitoring signal. An LD output correcting portion 9 outputs an LD output correcting signal based on the record shortage signal and the record surplus signal as well as a record data signal.

Abstract: Disclosed is a disk-like recording medium, a disk recording apparatus and a disk recording method, and a disk playback apparatus and a disk playback method. Disk ID is recorded over a circle of a burst cutting area on an optical disk. The circle is divided into n blocks, each of the blocks is divided into m frames, and ID information is recorded in each of the frames with k channel bits.

Abstract: The data recording and reproducing device includes a cantilever 11 having a probe h and extending so as to locate the tip of the probe h in the vicinity of a recording film 20, a piezo driving unit 12 for vibrating the cantilever 11, an optical lever 13 for detecting a displacement due to the vibration of the cantilever 11, a Z feedback circuit 33 for performing feedback control for the driving in a direction vertical to the table 21, a write circuit 18 for supplying a recording voltage to the cantilever 11 in response to a recording signal IN, a voltage circuit 16 and a variable bias circuit 17 for applying an AC voltage to the cantilever 11, and a V feedback circuit 34 for performing the feedback control for the bias voltage applied to the cantilever.

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 information recording medium according to an aspect of this invention includes a data area (A2) for recording user data and an address area (DMA address area) for recording address data that indicates the position of a defect management area that manages a defect present in the data area.

Abstract: Methods and devices are described for writing an optical record carrier, in which a mark representing recorded data is written in a phase-change layer of a record carrier by a sequence of radiation pulses. A rear heating pulse 24 is introduced after a last write pulse 23, 26 and a front heating pulse 25 is introduced before the first write pulse 22,26. The power level 13 of the front heating pulse and the power level 15 of the rear heating pulse may be dependent on the length of the mark to be recorded and on properties of the record carrier. The method results in a reduced jitter of the marks written, especially when writing at high recording speeds.

Abstract: A method of recording data optically to an optical disk having a plurality of sectors, in which each sector has a region to be recorded with data, the data is recorded in units of blocks, and the block includes a predetermined number of sectors and is a data unit including error correction codes. In recording data related to a content by dividing and recording the data in a plurality of sectors continuously, dummy data to be used for extracting a clock in PLL for data reproduction is recorded on a region adjacent before a sector from which data recording is started. The data related to the contents is recorded on sectors following the region recorded with the dummy data.

Abstract: A data processor compatible for use with a CD and a DVD includes a first modulation circuit for modulating recording data for recording on a CD to generate first modulated data. A second modulation circuit modulates recording data for recording on a DVD to generate second modulated data. A write signal generation circuit generates a first write signal, which is written to the CD, from the first modulated data, and a second write signal, which is written to the DVD, from the second modulated data. The write signal generation circuit is commonly used for the CD and the DVD to reduce the circuit area of the data processor.

Abstract: A defect detection device for detecting a defect of data recorded on a recording medium includes a waveform state detection part generating information representing a state of a waveform of a reproduced signal from the recording medium based on soft decision results obtained in process of reproducing the data in accordance with a maximum likelihood decoding algorithm corresponding to partial response, and a defect determination part determining the defect of the recorded data based on the information generated in said waveform state detection part.

Abstract: In a tracking controller for an optical pickup, a photodetector having four light reception parts receives return light from an optical disc and outputs light detection electric signals. Predetermined addition and subtraction operations are performed on the light detection electric signals from the light reception parts. A phase comparator compares phases and outputs a pseudo radial contrast signal. Bringing into tracking servo control is performed based on the pseudo radial contrast signal.

Abstract: An optical disk control device comprises a playback signal detection unit for detecting data recorded on a disk by irradiating the disk with a converged light beam; a signal switching unit for successively selecting plural data signals obtained by the playback signal detection unit, and performing time-division-multiplexing on the selected signals; an A/D conversion unit for converting an analog signal which has been time-division-multiplexed by the signal switching unit, into a digital signal; an A/D conversion command unit for generating an A/D conversion command of the A/D conversion unit; a serial transfer unit for serial-transferring the command signal generated by the A/D conversion command unit; a serial reception unit for receiving the signal from the serial transfer unit, and controlling the signal selection operation of the signal switching unit on the basis of the received signal; and an arithmetic unit for generating an optical disk drive controlling signal by performing arithmetic processing on t

Abstract: A rewritable type optical disc includes recording tracks formed with break portions; and recording marks corresponding to predetermined data and formed on the recording tracks. The recording marks are formed over the break portions on the recording tracks. If the predetermined data, such as control data, recorded as the recording mark is illegally altered, the position of the recording marks are changed and some break portions are not covered by the recording marks. Since the return light level of the break portion, which is not covered by the recording mark, is different from the return light level of the break portion covered by the recording mark, such illegal alteration of the predetermined data such as the control data may be detected.

Abstract: An objective lens for an optical pickup is configured such that, when a light beam having a wavelength corresponding to the optical disc requiring the higher NA is converged on the optical disc requiring the higher NA at the higher NA, the phase of light flux passed through the peripheral area is substantially the same as that passed through the central area. When a light beam having a wavelength corresponding to the optical disc requiring the lower NA is converged on the optical disc requiring the lower NA at the lower NA, the phase of light flux passed through a first annular region included in the peripheral area is different from that passed through the central area, and the phase of light flux passed through a second annular region, which is outside the first region, is substantially the same as that passed through the central area.

Abstract: An information recording medium includes a data area for recording data; and a drive information area for recording at least one piece of drive information. The data area is divided into a plurality of segmented areas in a radial direction of the information recording medium. Each at least one piece of drive information includes a recording and reproduction condition corresponding to at least one of the plurality of segmented areas.

Abstract: A method of recording data optically to an optical disk having a plurality of sectors, in which each sector has a region to be recorded with data, the data is recorded in units of blocks, and the block includes a predetermined number of sectors and is a data unit including error correction codes. In recording data related to a content by dividing and recording the data in a plurality of sectors continuously, dummy data to be used for extracting a clock in PLL for data reproduction is recorded on a region adjacent before a sector from which data recording is started. The data related to the contents is recorded on sectors following the region recorded with the dummy data.

Abstract: An adaptive writing method of a high-density optical recording apparatus and a circuit thereof. The circuit includes a discriminator for discriminating a magnitude of a present mark of input NRZI data and magnitudes of leading and/or trailing spaces of the input NRZI data, a generator for controlling the waveform of a write pulse in accordance with the magnitude of the present mark of the input NRZI data and the magnitudes of the leading and/or trailing spaces of the input NRZI data to generate an adaptive write pulse, and a driver for driving a light source by converting the adaptive write pulse into a current signal in accordance with driving power levels for respective channels of the adaptive write pulse. The widths of the first and/or last pulses of the write pulse waveform are varied in accordance with the magnitude of the present mark of input NRZI data and the magnitude of the leading and/or trailing spaces, thereby minimizing jitter to enhance system reliability and performance.