Abstract: An optical disk recording method for recording predetermined data on an optical disk on the basis of a first reference clock signal used for recording, the optical disk including a groove track having a wobble signal recorded thereon and a land track having a land pre-pit carrying track position information, the first reference clock signal being generated on the basis of the wobble signal reproduced from the optical disk, includes the steps of reproducing a pre-pit signal from the optical disk; generating a second reference clock signal from the pre-pit signal; detecting an amount of phase shift of the first reference clock signal using the second reference clock signal; and correcting the first reference clock signal on the basis of an average value of the detected amount of phase shift.

Abstract: An information processing apparatus for executing a process of recording data on a multilayer optical disk. The information processing apparatus includes: an encoding unit for encoding data to be written; a modulation unit for modulating the encoded data to generate a plurality of modulated data blocks corresponding to different recording formats; a pickup for sequentially writing the modulated data blocks in the different recording formats to different layers of the optical disk; and a control unit for controlling the writing of the modulated data blocks in the different recording formats so that writing processing per unit of modulated data is completed within processing time per unit of data encoded by the encoding unit.

Abstract: An optical disk recording method for recording predetermined data on an optical disk on the basis of a first reference clock signal used for recording, the optical disk including a groove track having a wobble signal recorded thereon and a land track having a land pre-pit carrying track position information, the first reference clock signal being generated on the basis of the wobble signal reproduced from the optical disk, includes the steps of reproducing a pre-pit signal from the optical disk; generating a second reference clock signal from the pre-pit signal; detecting an amount of phase shift of the first reference clock signal using the second reference clock signal; and correcting the first reference clock signal on the basis of an average value of the detected amount of phase shift.

Abstract: A reproduced signal waveform processing apparatus is provided. The apparatus includes an A/D converter for sampling a reproduced signal at a reproducing clock having a predetermined oscillation frequency; a first equalizer for equalizing a digital reproduced signal from the A/D converter; a second equalizer connected in series with the first equalizer for further equalizing the digital reproduced signal from the first equalizer; a phase frequency controller for detecting a phase frequency error between the digital reproduced signal from the first equalizer and the reproducing clock signal, and outputting a control signal on the basis of a result of the detection; and a variable frequency oscillator for varying the oscillation frequency in accordance with the control signal.

Abstract: An information processing apparatus for executing a process of recording data on a multilayer optical disk. The information processing apparatus includes: an encoding unit for encoding data to be written; a modulation unit for modulating the encoded data to generate a plurality of modulated data blocks corresponding to different recording formats; a pickup for sequentially writing the modulated data blocks in the different recording formats to different layers of the optical disk; and a control unit for controlling the writing of the modulated data blocks in the different recording formats so that writing processing per unit of modulated data is completed within processing time per unit of data encoded by the encoding unit.

Abstract: A reproduced signal waveform processing apparatus is provided. The apparatus includes an A/D converter for sampling a reproduced signal at a reproducing clock having a predetermined oscillation frequency; a first equalizer for equalizing a digital reproduced signal from the A/D converter; a second equalizer connected in series with the first equalizer for further equalizing the digital reproduced signal from the first equalizer; a phase frequency controller for detecting a phase frequency error between the digital reproduced signal from the first equalizer and the reproducing clock signal, and outputting a control signal on the basis of a result of the detection; and a variable frequency oscillator for varying the oscillation frequency in accordance with the control signal.

Abstract: A magnetic reproducer for reproducing data recorded on a magnetic tape by forming tracks sequentially and obliquely along a longitudinal direction of the magnetic tape, has magnetic heads for reproducing the information by sequentially scanning the tracks formed on the magnetic tape with a first track width for a first recording system or a second track width for a second recording system wider than that for the first recording system. And, a gap width between the magnetic heads is set at a value which is wider than the first track width and narrower than the second track width.

Abstract: In a magnetic recording device and method, a magnetic reproduction method and its method and a tape recording medium, the performance can be improved. In the case of successively and obliquely forming tracks along the longitudinal direction of a second magnetic tape having a width wider than a first magnetic tape and continuously recording recording data for at least two tracks in a digital recording format on each track, each track is to be formed at a predetermined track pitch set based on the recording time and the reproduction signal characteristic. Thereby, recording data based on the digital recording format which is applied to the first magnetic tape can keep a practically sufficient C/N ratio and can be recorded on the second magnetic tape for a long time. And thus, a magnetic recording device and method, a magnetic reproduction device and method, and a tape recording medium capable of improving the performance can be realized.