Abstract: A magneto-optic disk unit includes a cartridge holder having an insertion opening, an inside surface and first and second surfaces, an erroneous insertion preventing mechanism having at one end a stopper portion for prohibiting erroneous insertion of a magnetic disk cartridge and at the other end an insertion detecting portion for detecting insertion of a magnetic-optic disk cartridge, and a supporting mechanism for rotatably supporting the erroneous insertion preventing mechanism. The insertion detecting portion projects inside of the cartridge holder from an upper surface of the cartridge holder, so that when the magneto-optic disk cartridge is inserted the insertion detecting portion moves outside of the cartridge holder to allow insertion of the magneto-optic disk cartridge, and that when the magnetic disk cartridge is inserted the insertion detecting portion does not substantially move, thus permitting the stopper portion to prevent insertion of the magnetic disk cartridge.

Abstract: A double-sided reproducing disk player wherein reduction in size and simplification in structure of a carriage can be attained and reduction in number of parts and simplification in construction of the entire arrangement can be attained to attain reduction in overall size and also in production cost. The player comprises upper and lower face guide mechanisms for guiding a carriage, on which an optical pickup is carried, along upper and lower surfaces of a disk, respectively. The upper and lower face guide mechanisms are carried on a carrying device which is supported for tilting motion on a stationary frame of the player, and the tilt angle of the carrying device with respect to the stationary frame is adjusted by a tilt angle adjusting device. The tilt angle adjusting device includes an eccentric member on the stationary frame and a spring for biasing the carrying device into cooperation with the eccentric member.

Abstract: An automated disk library which provides the necessary rigidity and accuracy of positioning of the transport mechanism with respect to the storage bays and the disk drives without the attendant cost, bulk and weight of the prior art devices. The transport drive and support comprises a carriage member disposed in the shaftway with structure for locating the carriage with respect to an x-axis and a y-axis transverse of the shaftway while permitting motion of the carriage along a z-axis parallel to the shaftway. A plurality of guide surfaces are provided on the portion of the housing adjacent the shaftway with guide rollers rotatably mounted on the carriage and bearing on guide surfaces to locate the carriage with respect to the x- and y-axis.

Abstract: A track transverse detection signal generating circuit in a LD or a CD player, which comprises a presence signal amplifier for amplifying a presence signal indicating that an optical spot for reading information exists on a recording track, a controller for receiving a speed signal corresponding to a moving speed of the optical spot for reading information on the recording track to control an amplification level of the presence signal amplifier in response to the moving speed of the optical spot, and a presence signal comparator for receiving the presence signal which has been amplified and transmitted from the presence signal amplifier, for making a comparison between the amplified presence signal and a reference value, and for transmitting a pulse-shaped track transverse detection signal.

Abstract: An apparatus for rotationally driving an optical disk in an optical disk recording and/or reproducing apparatus capable of recording or reproducing signals from disks having different sizes includes a spindle motor for rotationally driving a disk, a servo unit for controlling the rotation of the spindle motor, and a control unit for detecting an activation response state of the spindle motor upon starting, and switching a gain of the servo unit on the basis of the detection result.

Abstract: Adjustable mounting structure for a compact disc player includes a platform to support the player; an arm supporting the platform; ball and socket swivel elements, one of the elements supporting the arm; and a bracket supporting the other of the ball and socket elements, the bracket attachable to included vehicle passanger compartment structure; the socket element adjustably clamping the ball element to frictionally resist relative swiveling thereof. Switching circuitry is to be connected with the platform and has terminals connectible withi) speaker circuitry,ii) audio circuitry, andiii) a player output connection.

Abstract: In the reproduction of data from one of N-frame sectors of an optical disk, data marks representing the front ends of the respective frames of a desired sector are detected and counted. When the number of the data marks is more than a predetermined value M (1<M.ltoreq.N), the reproduced data is accepted. Hence, the data accuracy can be ensured and the operating reliability of a data reproducing apparatus can be improved.

Abstract: A magnetooptic disk has circumferentially-spaced-apart, radially-aligned embossed sector areas which indicate data storage tracks. The sector areas include embossed signals which indicate track-following information, and in a second area which trails the track-following information, track-seeking information is carried by the embossed signals. A magnetooptic coating covers the entire disk including the embossed sector areas. Readback clock synchronization signals are recorded over the track-seeking area to enable synchronizing a readback phase-locked loop such that more of the areas between sector areas can be used for recording data signals. During track seeking, the track seek controlling embossed signals are read using intensity demodulation, while in track following, during a readback, the clock signals recorded over the embossing are read for synchronizing the readback circuits. During recording, the synchronization signals are recorded over the embossed area dedicated to track seeking.

Abstract: A record player is provided with a turntable brake for instantly stopping the turntable of the record player in playback when desired and a pair of balance wheels for permitting slant of the turntable within a predetermined range when manually operating the turntable. The turntable hereof has a peripheral drum portion extending downwardly from its bottom and a rubber shoe is mounted on one end of a pivoted lever arm. The lever arm is adapted to be actuated to press the rubber shoe against the drum portion of the turntable for stopping rotating movement of the turntable by means of friction.

Abstract: An optical storage medium is disclosed. In general, the storage medium includes a substrate, with a first, expansion layer, a second, reflective layer bonded to the first layer, and a third, retention layer bonded to the second layer, opposite the first layer. An opto-electronic system for recording data is also disclosed, along with a method of manufacture of the storage medium.