Abstract: The present invention provide an apparatus and method for verifying that a record carrier has been transformed from a first state to a second state in accordance with the state of a binary information signal being recorded thereon. In operation, the apparatus detects the signal generated by the record carrier during the supposed transformation and compares this signal to the corresponding portion of the binary information signal to determine whether or not the transformation has taken place, i.e., verifies the transformation. The present invention, in one embodiment, is employed in an optical disk system.

Abstract: An optical head and supporting apparatus has an optical head for irradiating a parallel beam in a direction perpendicular to a recording surface of an optical disk, an objective lens rigidly mounted on the optical head for receiving the parallel beam from the optical head, tracking drive coils for driving the optical head over the whole recording range in a first direction transverse to the recording tracks of the optical disk, focusing drive coils for driving the optical head in a second direction perpendicular to the recording surface of the optical disk, and a support mechanism made of wire-shaped elastic bodies for supporting the optical head freely movably in the first and second directions over the whole recording range in the first direction of the optical head. The support mechanism is fixedly mounted through elastic bodies on a part of a structural body independent of movement of the optical head.

Abstract: Track jumping in the present system is accomplished by using a two step track jump method which accelerates the tracking actuator toward the desired track at maximum acceleration and then decelerates the tracking actuator at a maximum deceleration so that the desired track is reached in a minimum amount of time without the actuator ringing. A matrix containing the times for each jump pulse from track X to track Y is recorded. The matrix table is updated after each jump to compensate for variance factors. The table is stored in memory which allows the system to become more accurate with each jump. If the actuator falls short of the desired position, the jump pulse next applied is lengthened slightly. If the jump pulse causes the actuator to overshoot, the desired position the jump pulse is shortened for the next jump.

Abstract: The present method operates upon an optical disk type servo-system of the type having an optical tracking servo for maintaining a lens centered over a track on a disk and a tracking position servo for moving an optical head's lens to a desired position. Included within such a system is an eccentricity sub-system for providing a compensating sine wave signal for reducing errors in tracking due to disk decentering. The present method automatically adjusts the gain in one of the servos to match the gain appearing in the other servo so as to improve the smoothness of control when switching between the servos.

Abstract: A tilt device for controlling the optical axis of an optical head in an optical disc playback device for optical discs such as a Laser Vision Disc and a Compact Disc in a perpendicular relation to the surface of an optical disc comprises a tilt mechanism for tilting a feed shaft disposed in the radial direction of an optical disc and having an optical pickup mounted reciprocably thereon so as to change the angle of optical axis of the optical pickup, a detector for detecting distance between the optical pickup and the optical disc and producing a detection signal, and a servo system responsive to the detection signal for controlling the tilt mechanism to maintain the distance between the optical pickup and the optical disc constant.

Abstract: An editing apparatus controls a plurality of video tape recorders so that a slow motion picture, a quick motion picture or a combination of the slow motion picture and the quick motion picture reproduced by the video tape recorder can be edited on a video tape. The editing apparatus includes an input keyboard to input data of a desired tape speed at first and second tape positions, a calculating circuit for calculating a tape speed at any position between said first and second positions on the basis of the input data, and a control circuit for controlling a tape speed of said video tape recorders in response to an output signal of said calculating circuit.

Abstract: There is disclosed a magnetic recording and reproducing apparatus provided with a rotary drum wherein audio heads for recording/reproducing an audio signal, video heads for recording/reproducing a video signal, an erasing head for erasing recorded information are provided on the outer circumferential surface of the rotary drum, and a running magnetic tape is obliquely wound at a predetermined length on the outer circumferential surface.