Abstract: A tracking device usable in an optical information recording and reproducing apparatus for an optical information record medium on which a plurality of tracks are arranged substantially parallel in a first direction. The device includes a light source, a first optical system for forming a small spot on the record medium by converging a light beam from the light source, a second optical system for obtaining the light beam from the record medium, a detecting device for receiving the light beam obtained by the second optical system to output a tracking signal, a vibrating device for vibrating the spot relative to the record medium in a second direction intersecting the first direction, a control device for effecting tracking control with respect to a track, and a selecting device for selectively actuating the vibrating device and the control device in accordance with the tracking signal from the detecting device.

Abstract: In an optical information recording medium of the type wherein information is recorded or reproduced when a light beam scans each of a plurality of mutually parallel tracking tracks, an auxiliary track is extended between the adjacent tracking tracks and has at least one portion in parallel with the tracking tracks. In a method of recording or reproducing information by scanning a light beam on each of a plurality of mutually parallel tracking tracks on the recording medium, the recording medium has an auxiliary track which is extended between the adjacent tracking tracks and which has at least one portion in parallel with the tracking tracks and the light beam is kicked in the parallel portion of the auxiliary track.

Abstract: There is disclosed an optical card recorder-reader, in which erroneous signal recording, caused by a low-level light beam when it is stopped at a position for a prolonged period between writing and/or reading operation, either by interruping the irradiation, or by reducing the power of irradiation, or by placing the light beam outside the recording area, when the recording or reading operation is not in progress.

Abstract: An information recording medium comprises a plurality of record bands each having a plurality of information recording tracks arranged orthogonally to a direction of the track, and the record bands are arranged orthogonally to a direction of arrangement of the tracks. Identification fields are provided in the respective bands to allow identification of track groups.

Abstract: A method and apparatus for accessing a track in a recording medium during a stopped state of recording or reproduction. The method includes accessing a recording and/or reproducing device to a desired track of a plurality of tracks on the information recording medium. The recording and/or reproducing device and the recording medium are not relatively moved in a longitudinal direction of the tracks, while the recording and/or reproducing device is moved relative to the recording medium in a direction which crosses the tracks.

Abstract: This invention relates to an information reproducing method and apparatus in which a phase locked loop (PLL) circuit produces a clock signal from a reproduced signal and includes a sensitivity varying mechanism. The sensitivity of the PLL circuit is increased or decreased relative to when a tracking error signal is low or high, respectively. Further, if the reproduced signal drops, the frequency and phase of the clock signal are held. Then, immediately after the reproduced signal is regained and the hold is released, the sensitivity of the PLL circuit is lowered to a value less than that prior to the drop in the reproduced signal.

Abstract: An optical information recording and reproducing apparatus comprises, an optical head for recording and reproducing information on and from a card-shaped optical recording medium, first means for relatively reciprocally moving said optical head to said card-shaped optical recording medium, and control means for controlling a relative speed between said optical head and said optical recording medium, said control means keeping a constant relative speed between said optical head and said optical recording medium in a record area of said optical recording medium and changing the relative speed between said optical head and said optical recording medium and reversing the direction of the relative movement between said optical head and said optical recording medium in areas outside of the record area.

Abstract: Method and apparatus for recording information on a card-shaped optical information recording medium with a light beam and/or for reproducing information recorded on the medium. The apparatus includes a device for irradiating the medium with a light beam, a device for causing relative reciprocal movement between the medium and the light beam, and a device for terminating or displacing the light beam on the medium, after the lapse of a predetermined period of time from a moment when the relative speed of the medium and the light beam is reduced below a predetermined speed. The method includes the steps carried out by the apparatus.

Abstract: An optical information recording and reproducing apparatus for an optical information record medium on which a plurality of tracks are arranged substantially in parallel, comprises a light source, a first optical system for guiding a light beam from the light source, onto the record medium, a second optical system for obtaining the light beam from the record medium, a detecting device for receiving the light beam obtained by the second optical system to output at least one of a focusing signal and a tracking signal, an adjusting device for adjusting at least one of focusing and tracking operation in accordance with at least one of the focusing and tracking signals, a reciprocating device for causing the record medium to reciprocate, a control device for controlling the reciprocating device, and a change device for changing at least a servo gain of the adjusting device in accordance with at least a signal from the control device.

Abstract: An information reproducing medium comprises plural tracks for recording information arranged to form a band and such plural bands are arranged normal to the direction of the track arrangement. The track has no area for obtaining an information reproducing clock. In a reproducing method, when information on one track of one band is to be reproduced, an information reproducing clock is derived from at least a portion of information on a track other than the one track, preferably a track adjacent thereto.

Abstract: An apparatus for recording or reproducing information in or from an optical disc, has a semiconductor laser system, a split photosensor, a signal processing circuit, and a disc controller with a CPU and a memory. Defective sectors of the optical disc are detected, and information recording/reproduction is performed for only nondefective sectors.

Abstract: Method and apparatus for seeking a desired one of a plurality of tracks formed on an optical information carrier are disclosed. The tracks are scanned by a light spot traversing the tracks, the tracks traversed by the light spot are detected, and the tracks detected are counted by a counter. When the light spot traverses a defect area on the track, the track which is not detected because of the defect area is also counted by the counter.

Abstract: An information recording medium includes: a plurality of information tracks for storing information to be recorded; a first area for separating and discriminating an information track from another information track adjacent to the information track in the direction of information sequence; and a second area for separating and discriminating the information track from another information track adjacent to the information track in the direction perpendicular to the direction of information sequence, the second area having a common portion to the first area.

Abstract: An optical information recording medium in the form of a card having tracking tracks for obtaining a tracking signal and clock tracks for obtaining a clock signal arranged alternately and record zones for recording information between each of the tracking tracks and each of the clock tracks, and apparatus for recording/reproducing information using the recording medium.