Sanyo Electric Co., Ltd.

Yasushi Hanamoto

Akira Tsukihashi

Koji Hayashi

Toshihiko Hiroshima

Toru Tanaka

Tohru Tanaka

Tsuyoshi Yamamoto

Katsuki Hattori

Hideki Osawa

Yutaka Imamura

Koji Tsukagoshi

Shinji Seki

Hitoshi Ogura

Yasuki Mori

In an optical disk recording and reproducing device which uses an optical disk having at least a first recording layer and a second recording layer, a thickness of a spacer section between the first recording layer and the second recording layer is measured, an amount of defocus with respect to the second recording layer is set based on the measured spacer thickness, and a focus servo operation is performed for focusing the laser light irradiated from an optical pickup device on the second recording layer.

Method of controlling focus of optical disk recording and reproducing device

An optical disk apparatus is disclosed which makes accesses on a block-by-block basis to an optical disk having a recording track segmented into first recording areas by first address information correlated with wobbling information of the recording track, the block being a unit for error correction consisting of a plurality of the first recording areas. The optical disk apparatus comprises an access control unit which, when an access is made to a second recording area consisting of a plurality of the first recording areas, provides access control in sequence without applying any data modulation and/or demodulation process to each of the plurality of first recording areas constituting the second recording area.

Enhanced testing region access for optical disks

An operation for recording a recording signal onto a disk () is interrupted, when an amount of signal data stored in a buffer RAM () for temporarily storing the recording signal is less than an interruption setting value during performing of the recording operation. Moreover, when the amount of signal data stored in the buffer RAM () increases and indicates a resumption setting value, the signal recorded on the disk () before interruption is reproduced, and the recording operation is resumed based on the reproduced signal. Moreover, recording properties are detected by the signal reproduced before resumption of recording.

Optical disk recording/reproducing method and apparatus in which recording properties of the disk are detected when recording speed is changed

A controller for a data recorder for recording data that records data in a continuous manner regardless of interruptions. An encoder encodes data that is to be written to a recording medium. A synchronizing circuit synchronizes the data read from the recording medium with the encoded data when the writing of data to the recording medium is interrupted. A first retry determination circuit determines whether an address of the data read from the recording medium and an address of the data provided to the encoder match. A second retry determination circuit determines whether the timing for reading data from recording medium and the timing for encoding data match. A restart circuit restarts the writing of data to the recording medium based on the determinations of the first and second retry determination circuits.

Controller for data recorder

A data recorder for recording data that records data in a continuous manner regardless of interruptions. An encoder encodes data that is to be written to a recording medium. A synchronizing circuit synchronizes the data read from the recording medium with the encoded data when the writing of data to the recording medium is interrupted. A first retry determination circuit determines whether an address of the data read from the recording medium and an address of the data provided to the encoder match. A second retry determination circuit determines whether the timing for reading data from recording medium and the timing for encoding data match. A restart circuit restarts the writing of data to the recording medium based on the determinations of the first and second retry determination circuits.

Data recorder

To provide a method for optimizing the optical output from an optical head when recording data onto an optical disk, each time a suspension of data recording onto the disk is determined, the optical head reads data recorded onto the disk before the suspension, and recording state of this data is judged. Based on the judged recording state, the optical output from the optical head to be emitted when resuming the data recording is controlled. A timing at which to suspend data recording can be desirably set, so that the recording state of the recorded data in the disk can be judged at desirable timing in data recording operation, so that the optical output from the optical head is controlled based on the judged recording state.

Optical head optical output setting method and optical disk recording apparatus

A pickup control circuit () for performing a control operation of an optical pickup () and an error detection circuit () for detecting an error signal from a servo signal obtained from the pickup control circuit () are provided. During an operation to change to a faster recording speed, a playback operation for an already recorded signal is performed at the recording speed after the change, and an error detection level is set on the basis of characteristics of the servo signal in the playback operation state.

Optical disc recording and playback apparatus

A controller of a data recorder that records data on a recording medium such that the occurrence of buffer underrun errors are prevented. Data encoded by an encoder is recorded on the recording medium. A decoder decodes the data recorded on the recording medium. The data recorder interrupts the recording of data when a buffer underrun is likely to occur. The controller restarts the recording of data when the decoded data and the encoded data are synchronized. When the decoded data is delayed from the encoded data, the controller stops the encoding until the decoded data catches up with the encoded data.

Controller of data recorder

When during the operation of recording a signal onto a disk the amount of signal data stored in a buffer RAM for temporarily storing a recording signal falls below an interruption set value, the recording operation on the disk is interrupted. Subsequently, when the amount of signal data stored in the buffer RAM increases to a resumption set value, a signal recorded on the disk before the interruption is reproduced. On the basis of the reproduced signal, the recording operation is resumed from a position where the recording is interrupted. The operation of resuming recording that is interrupted due to a shock is permitted. The operation of resuming recording after the interruption of the recording is started from a position that is before the position where the recording is interrupted.

Recording control method for optical disk recording and reproducing apparatus

To provide a spindle motor control method adapted to an optical disk recording and reproducing apparatus capable of recording a signal onto a disk using a laser applied from an optical pick-up, a reference signal originated from a disk ( ) and a reference signal necessary for signal recording are synchronized to each other when resuming signal recording once suspended. The synchronization is established without using a phase error component. Once synchronization is established, a phase error component is added to a servo signal of the spindle motor ( ). A gain for a phase error component is begun gradually increasing after a phase error component is begun being added to a servo signal. An upper limit value of the gain of a phase error component to be added is determined depending on the location of a part on the disk ( ) at which to resume the once suspended signal recording.

Spindle motor control method of optical disk recording and reproducing apparatus

Additional recording data is written continuously with data already recorded on a disk and writing of additional data is started in synch with recorded data. The optical head reads data recorded on the disk just before recording is halted every time the record decision unit judges that recording is to be halted. The record-status detection unit detects the formation status of the recorded data. The head output control unit sets the luminous output of the optical head 1 at the beginning of additional writing according to the recording state judged by the record-state detection unit . Thus, the formation status of data recorded on a disk is detected to allow the luminous output of the optical head to be set to an optimum record level.

Growing community of inventors

Hanyu, Japan

Yasushi Hanamoto