Abstract: A method of storing calibrated optical parameters is presented. In some embodiments, calibrated optical parameters are stored in place of stored parameters. In some embodiments, averages between the calibrated operating parameters and stored optical parameters are stored. In other embodiments, the stored optical parameters are allowed to vary only by a maximum amount. In some embodiments, if the calibrated parameters vary by more than threshold values, then the calibrated parameters are not stored.

Abstract: An optical disc player having an optical pickup records and retrieves information on an optical disc while the optical disc is rotating. A rotation pulse is generated each time the optical disc rotates through a prescribed angle. A rotation frequency data representing a frequency of the rotation pulse is also generated. A servo processor performs servo processing for rotation control on the optical disc in accordance with the rotation frequency data. A sampling pulse generator performs computational processing on an input data signal to generate a sampling pulse. The sampling pulse generator also corrects the rotation frequency data based on a phase error between the sampling pulse and the rotation pulse to use a corrected rotation frequency data as the input data signal. Another servo processor performs servo processing for repetitive control on the optical pickup using the sampling pulse.

Abstract: Optimizing performance of physical disk drives in a disk array storage device with a plurality of logical volumes is accomplished by accumulating statistics over an interval to select two logical volumes for an exchange. After testing to determine any adverse effect of making that change, the exchange occurs to more evenly distribute the loading on individual physical disk storage devices. One set of statistics, seek time, is obtained by combining estimated disk access information and an interpolated seek time obtained from a template that stores characteristics seek times among different pairs of segments that define a physical disk device independently of a logical volume configuration.

Abstract: Playback signal amplitude drops and continuity of the signal track amplitude is lost at the beginning the data recording area when data is incrementally written to optical discs such as DVD-R or DVD-RW media. Feed-forward control quickly settles semiconductor laser recording power to the target power level immediately after an incremental recording starts. While recording continues, feedback control maintains laser power at a desired recording power level even when the required current supply varies due to the temperature characteristics of the semiconductor laser when recording lasts for an extended period of time. A semiconductor laser control method and semiconductor laser control device thereby maintain laser power at a stable target recording power level quickly and for as long as recording continues.

Abstract: In a spherical aberration correcting apparatus, a test recording unit is configured to perform a test recording on an optical disk. A characteristic obtaining unit is configured to obtain a characteristic corresponding to a parameter by the test recording. The parameter is correlated with a spherical aberration. A correction amount deciding unit is configured to decide an optimum correction amount of the spherical aberration so as to minimize the spherical aberration according to the characteristic of the parameter. A spherical aberration correcting unit is configured to correct the spherical aberration according to the optimum correction amount of the spherical aberration.

Abstract: An information recording apparatus and a method therefor which can form a beam guide groove in the shape of highly accurate rectangle having abrupt edges. A recording mark is formed by exposing a recording medium with a recording beam having a beam diameter smaller than the beam guide groove, while periodically vibrating the recording beam in a direction perpendicular to a recording track on the recording medium, or in both horizontal and vertical directions of the recording track.

Abstract: Servo control circuitry 300 includes a digital to analog converter 402 for converting digital servo control data into a pulse width modulated signal. A first conductor transmits the pulse width modulated signal to an external device 409. A second conductor transmits a reference signal derived from the clock signal to external device 409, external device 409 differentially receiving the pulse width modulated signal with respect to the reference signal.

Abstract: An information recording apparatus for recording tracks includes: a rotation drive section (RDS) that supports and rotates a master disk with a resist layer; an exposure beam emitting section (EBES) deflectably applying an exposure beam to the disk to form a spot thereon; a relative movement drive section (RMDS) translating the RDS relatively to the spot in a radial direction of the disk; an emission controller supplying the EBES with an instruction for modulating an intensity of the exposure beam according to data to be recorded; and a movement controller supplying the RMDS with an instruction for moving the RDS with the rotating disk by a predetermined moving amount for each disk rotation.

Abstract: An adaptive motion controller for driving a servo motor. The adaptive motion controller has an amplifier including a voltage command which can be set at a voltage at which the amplifier will be operated, a frequency selector which can be set at a frequency at which the amplifier will be operated, a power supply having a current feedback, and a control for driving the servo motor in a test mode wherein the voltage command is set at a selected voltage, and the frequency selector is sequentially set with a series of different frequencies. The servo motor is operated at each frequency, and the frequency of the series of frequencies that has the lowest current feedback is determined and the frequency selector is set at that frequency when the amplifier is operated to drive the servo motor.

Abstract: In a wobble-format type optical recording medium 10 involving a guide groove 11 wherein the guide groove is allowed to meander over substantially the whole length thereof to form wobble, and wobbled intermittent sections 12 where there are no meandrous area are placed at predetermined positions in the wobble; a first wobbled intermittent section 12a for determining reference position is disposed at at least one reference position A in the optical recording medium, and furthermore, a second wobbled intermittent section 12b is disposed selectively at each predetermined position B apart from each reference position by a predetermined distance.

Abstract: An information recording apparatus and a method therefor which can form a beam guide groove in the shape of highly accurate rectangle having abrupt edges. A recording mark is formed by exposing a recording medium with a recording beam having a beam diameter smaller than the beam guide groove, while periodically vibrating the recording beam in a direction perpendicular to a recording track on the recording medium, or in both horizontal and vertical directions of the recording track.