Abstract: A disk testing apparatus that sets a predetermined condition of a recording density for a disk apparatus, and conducts a test relating to at least readout of data stored in the disk apparatus includes a condition relaxing unit that relaxes, when a result of the test is unsatisfactory, a condition of the recording density currently set for the disk apparatus to set a new condition of the recording density; and a re-testing unit that re-conducts the test on the disk apparatus to which the new condition is set.

Abstract: A shock detection device can detect a slight shock without mis-detection of shocks due to noise in a shock sensor signal. The shock detection device is adapted to output a shock detection signal for stopping writing into a disk medium when a shock applied to the disk medium satisfies a prescribed condition. The shock detection device includes a shock sensor that detects a shock applied to the disk medium and outputs a corresponding shock sensor signal, a variable shock detection slice value setting part that sets a threshold for the shock sensor signal based on a position error signal, a shock sensor signal correction part that outputs, as a new shock sensor signal, a signal by removing noise generated in synchronization with writing from the shock sensor signal, and a shock determining part that outputs a shock detection signal when the shock sensor signal exceeds the variable shock detection slice value.

Abstract: A tracking control method measures an optimum offset by measuring a light beam irradiation state of a light beam while offsetting a tracking target position of the light beam on a recording medium so that an optimum light beam irradiation state is obtained at the tracking target position, and carries out a tracking control by setting the measured optimum offset.

Abstract: A storage apparatus rotates an optical recording medium at two or more kinds of rotational speeds. The rotational speed is decreased when a read or write margin becomes less than or equal to a first predetermined value or, when a frequency of generation of a servo abnormality of a tracking servo and/or a focus servo is greater than or equal to a first predetermined frequency. On the other hand, the rotational speed is increased when the read or write margin becomes greater than or equal to a second predetermined value or, when the frequency of generation of the servo abnormality of the tracking servo and/or the focus servo is less than or equal to a second predetermined frequency.

Abstract: A data reproduction apparatus includes first and second sampling parts which sample a reproduced signal from a recording medium in synchronism with first and second clock signals synchronizing respectively with leading and trailing edges of the reproduced signal and output leading and trailing sampled values, respectively, and a combination part which generates combined sampled values based on the leading and trailing sampled values. Recorded data is reproduced based on transition states of the combined sampled values output from the combination part in accordance with a maximum likelihood decoding technique corresponding to a predetermined partial response waveform.

Abstract: A recording medium and an information storage apparatus having high formatting efficiency are provided. The recording medium and the information storage apparatus give IDs for data to be stored. In one embodiment, one ID is provided for two data areas, and no two IDs are situated in line with each other on two adjacent tracks.

Abstract: A seek control method carries out a seek to a target position on a recording medium by moving a light beam spot which is irradiated on the recording medium. The recording medium has a first region in which information recording is made as variations in optical or magneto-optical properties and a second region in which information recording is made as variations in geometrical configuration, and the first and second regions are provided in different areas on a recording surface of the recording medium. The seek control method includes the step of carrying out a control so that a seek operation from a seek start position within the first region to a seek target position within the second region and a seek operation from a seek start position within the second region to a seek target position within the first region differ.

Abstract: A predetermined electric current is supplied to coil by changing a pulse width of a voltage applied to the coil according to a current instruction value. An electric current which flows through the coil is detected; the thus-detected current value is compared with the current instruction value; the voltage applied to the inductance device is turned on/off according to the comparison result; and an off time for which application of the voltage to the coil is interrupted is controlled according to the current instruction value.

Abstract: A track servo control perform follow-up control of an optical beam to a track of an optical disk, and control the vibration of the optical beam due to the ID pit noise of the optical disk. The control system is comprised of a feedback control block for feedback-controlling the actuator by the track error signal from the actuator and the learning control block. Since the optical disk ID pit noise is periodic noise, the learning control block learns this, inputs the learning result to the feedback control system. The learning result is subtracted from the learning input, and the signal after subtraction is learned in order to converge the learning. Therefore even if the periodic ID pit noise is applied, this noise can be removed from the control loop and the vibration of the actuator due to periodic noise can be decreased, making a stable track follow-up operation possible.

Abstract: An information storage apparatus includes a mark reading section for reading a mark written on an information storage medium. A recording state changing section is provided for changing a recording state in an adjacent region situated next to a region from which the mark reading section fails to read a mark, so as to reduce cross talk caused by the adjacent region. The mark reading section reads the mark in the failed region again after the recording state changing section changes the recording state in the adjacent region.

Abstract: A magneto-optical recording medium processing apparatus of the present invention limits, via a predetermined current limiting means, the bias current applied to a bias coil during seek, when a seek current is applied to a carriage. In accordance therewith, it is possible to reduce the peak of the sum current, which is the total of the seek current and the bias current, and the current consumption of the entire apparatus can also be curbed. Current limiting means, for example, sets a bias current that is smaller than the specified value of the bias current required at media access time, and sets a bias current value such that the total of the seek current and bias current does not exceed an allowable current.

Abstract: An optical recording medium is provided with a substrate having a land and a groove alternately arranged in a predetermined direction, a data recording region provided on the land and the groove, and an identification mark recording region recorded with a data block identification mark. The identification mark recording region is provided on only one of the land and the groove.

Abstract: An optical recording medium is provided with a substrate having a land and a groove alternately arranged in a predetermined direction, a data recording region provided on the land and the groove, and an identification mark recording region-recorded with a data block identification mark. The identification mark recording region is provided on only one of the land and the groove.

Abstract: A shock detection device can detect a slight shock without mis-detection of shocks due to noise in a shock sensor signal. The shock detection device is adapted to output a shock detection signal for stopping writing into a disk medium when a shock applied to the disk medium satisfies a prescribed condition. The shock detection device includes a shock sensor that detects a shock applied to the disk medium and outputs a corresponding shock sensor signal, a variable shock detection slice value setting part that sets a threshold for the shock sensor signal based on a position error signal, a shock sensor signal correction part that outputs, as a new shock sensor signal, a signal by removing noise generated in synchronization with writing from the shock sensor signal, and a shock determining part that outputs a shock detection signal when the shock sensor signal exceeds the variable shock detection slice value.

Abstract: In a data reproducing apparatus, a monitor edge sample value is generated based on a second sample value at a trailing edge of the reproduction signal and a change amount of the monitor edge sample value is generated as an offset amount in a first processing part. Then, the offset amount is supplied to a second processing part where the second sample value is obtained by sampling the reproduction signal at the trailing edge. Then, the second processing part restores data based on the reproduction signal and the offset amount.

Abstract: A recording medium and an information storage apparatus having high formatting efficiency are provided. The recording medium and the information storage apparatus give IDs for data to be stored. In one embodiment, one ID is provided for two data areas, and no two IDs are situated in line with each other on two adjacent tracks.

Abstract: A storage apparatus has a function of controlling rotation of a recording medium which is divided into a plurality of zones in a radial direction thereof and employing a ZCAV system. The storage apparatus is provided with a setting part for setting a mode to one of a normal mode in which the recording medium is controlled to rotate at a first rotational speed, and a high-speed mode in which the recording medium is controlled to rotated at a plurality of second rotational speeds respectively corresponding to a plurality of areas to which the recording medium is divided in the radial direction thereof.

Abstract: A storage apparatus uses a light beam to reproduce information from a recording medium having an information region with a recording format which includes a header including position information and a recording field including a data field for recording data. The storage apparatus is provided with a light source for emitting the light beam, and a control section for controlling a power L2 of the light beam in a vicinity of a start of the recording field to become higher than a power L3 at the data field of the recording field.

Abstract: A magneto-optical recording medium device of the present invention optimizes a magnetic field forming the front mask and a magnetic field forming the rear mask by use of a single bias magnetic field generator, by shifting the peak position of the bias magnetic field in the magneto-optical recording medium device so as to deviate from the center of the laser beam spot in a tangential direction of the magneto-optical recording medium, enabling extended recording and reproduction margins.

Abstract: The present invention aims at providing an inexpensive optical information storing device that produces reduced cross talk. An optical information storing device has a cyclic data output circuit 14—1 that outputs cyclic data in which values are repeated every 5 bytes, and an EXOR circuit 14—2 that calculates the exclusive-OR (EXOR) of recording data input thereto via a buffer 14—5 and the cyclic data and inputs the calculation result to an RLL modulation circuit 14—3 as data to be recorded.