Abstract: A method for the reproduction of data, such as digital audio data and/or video data, stored on a storage medium, for example, on an optical storage disk, in a playback device, in which an accelerated selection may be possible of storage media to be reproduced or to be rejected by playback device. In a first operating mode, data are filed in, for example, a nonvolatile memory during a play-back process of the storage medium. In a second operating mode, the storage medium is selected, for example, for a playback process and a reproduction process. Within a timespan during which the selected storage medium is brought from a magazine into a playback position, in which the data stored in the storage medium may be read out by a read device, or into an eject position, from which the selected storage medium may be retrieved, at least a part of the data filed in the memory is played back and reproduced.

Abstract: A method for performing a track skip and a playback device for optical storage disks enable an accelerated track skip in the case of a non-moving storage disk in which a time is determined for the track skip of a read device between a current track and a selected track of a storage disk inserted in the playback device, as a function of the tracks to be skipped in this instance, and the read device is moved in the direction of the selected track for the determined time. In response to a track skip request, the read device is moved in the direction of a lead-in area of the optical storage disk until a starting position is detected. The time necessary for the track skip from starting position to the selected track is determined from this track.

Abstract: A method for performing a track skip and a playback device (10) for optical storage disks (15) are proposed that enable an accelerated track skip in the case of a non-moving storage disk (15). A time is determined for the track skip of a read device (2) between a current track and a selected track (3) of a storage disk (15) inserted in the playback device (10), as a function of the tracks to be skipped in this instance, and the read device (2) is moved in the direction of the selected track (30) for the determined time. In response to a track skip request, the read device (2) is moved in the direction of a lead-in area (20) of the optical storage disk (15) until a starting position (25) is detected. The time necessary for the track skip from starting position (25) to the selected track (30) is determined from this track (30).

Abstract: An electrical device allows voltage to be supplied with minimal power loss. The electrical device has elements with differing supply voltage demands. The same supply voltage is supplied in each case to the elements. The supply voltage can be switched over. The supply voltage is set as a function of the currently highest voltage demand of the elements. The electrical device can be configured as a playback device for optical memory disks, and can include a device for driving an optical memory disk inserted into the playback device and for positioning a scanning unit.

Abstract: A disc player is proposed for playing discs with optically stored data on which information is digitally stored in tracks. The disc player has a read/write memory for buffering data blocks that are read into the read/write memory at a first clock rate and are read out of the read/write memory at a second clock rate. To fill the read/write memory, the first clock rate is selected to be greater than the second. The data stored in the read/write memory can be read out throughout the duration of a track jump. Moreover, an operating mode is provided in which excerpts of music pieces stored on a compact disc are played in sequence. At the first clock rate, a sufficiently large quantity of data can be stored in the read/write memory to ensure that the data can be reproduced at the second clock rate throughout the entire duration of the jump times.

Abstract: A method is proposed which serves to control the focusing of a light beam, aimed at a rotating recording medium (25) for reading data, of a scanner (15, 20) onto the recording medium (25) and the guidance of the light beam along the data tracks of the recording medium (25), each by means of a respective control circuit. The scanner (15, 20) and the recording medium (25) are mounted on a fundamental substrate (10) in at least one housing (1), and the at least one housing (1), together with the fundamental substrate (10), the scanner (15, 20) and the recording medium (25), forms a coupled mechanical oscillator, which is vibrated as a function of a vibration spectrum (75); the scanner (15, 20) is accelerated by the vibration and a relative motion of the recording medium (25) with respect to the scanner (15, 20) is effected, and the amplitudes of the relative motion and the accelerations have a frequency response.

Abstract: An electrical device (1), especially a CD changer, is proposed, which offers protection against theft. An electrical device (1) is connected by a connecting cable (35) to a second electrical device (5), especially to a car radio. The connection has a first pole (95) for a first reference potential (15) and a second pole (100) for a second reference potential (25). In the second electrical device (5), the first reference potential (15) is connected to the second reference potential (25). A third pole (55) contains a supply voltage feed for the first electrical device (1). In the first electrical device (1), a control unit (40) is provided for controlling the first electrical device (1). When the connection between the first and second poles (95, 100) is cut, the residual charge remaining in the first electrical device (1) produces a voltage difference between these two poles (95, 100), as a result of which a security procedure is initiated in control unit (40).

Abstract: An optical recording and/or playback system having tracking and focus regulating circuits. Mechanical shock and/or disc defects are detected and the adverse effects on the tracking and focus regulating circuits are reduced.

Abstract: An optical disc record playback apparatus includes tracking circuitry for radially translating the scanning pickup device during normal playback of the disc. Coarse and fine drive circuits are responsive to tracking error signals to provide coarse and more precise radial translations respectively. The tracking error signals are monitored for the occurrence for abnormalities such as may be produced by dust on the disc surface, and responsive to the detection of such abnormalities the coarse drive system is disabled to preclude the pickup from leaving the track.

Abstract: A disc playback apparatus includes a system for scanning a disc and storing in memory, an address associated with every point on the disc where the scanning device mistracks. A modified regulating signal is calculated for guiding the scanning device back onto the desired data track, from the value of the regulating signal generated by the tracking regulation circuit prior to track loss. The modified regulating signal is also stored in the memory, and during every subsequent reading of the disc, upon encountering track areas associated with stored addresses, the tracking regulation circuit is provided a corresponding modified regulating signal in order to maintain the scanning device near the desired data track. In further scans of the disc successive modified track regulating signals are iteratively generated and tested for tracking response until a substantially optimum modified signal is generated.

Abstract: Process for stopping a record-shaped, rotating information medium, for example, a CD. CD-players, for example, are provided with a loading and unloading mechanism for the information medium, the CD. However, before a CD can be automatically unloaded by the CD-player after reproduction or activation of a STOP-key, the rotation of the CD must be stopped in order to avoid damages of its sensitive surface. Because the moment of inertia and the diameter of records (CDs) are varied, and because a small mini-CD exists, it may occur that the CD is still rotating during the unloading process. To stop the record (CD) safely independently of its moment of inertia and its size, a first applied braking pulse (B1) causes the record (CD) to be braked to full stop and subsequently to be accelerated in the opposite direction.

Abstract: A method of reading recorded-data on a spiral data track of a rotating recording medium which is scanned by a radially moveable scanning device. The scanning device follows the spiral data track and appears to shift from one track to another. The directory data are divided into a plurality of directory data blocks and stored on the spiral data track. Each of the data blocks represents a different characteristic of the recorded-data and at least n+1 identical blocks for each characteristic are sequentially arranged on the spiral data track, n being a whole number. The directory data are read by moving the scanning device from one data block to another. The motion between data blocks occurs either along the same track, inwardly from one track to another, or outwardly from one track to another and therefore the scanning of all n+1 blocks for every characteristic is not necessary.

Abstract: A method of adjusting the moveable unit of a positioning device having a light source and a photodetector for scanning markers identifying positions at which the moveable unit is to be located includes the steps of accurately and manually positioning the unit at one of the identifying positions. The unit is then automatically driven to a second position where the output signal of the photodetector is maximum. The deviation from the first position to the second position is stored as an offset which is subsequently used to accurately position the moveable unit.

Abstract: In CD-players with a memory having A storage positions for the storage of titles recorded on a CD-record it can happen, that more titles C are on the CD-record than storage positions A provided therefore in the CD-record. In order to use the storage space better in these cases and to keep the access times to the single titles low, the difference of the start times of each two consecutive titles are stored, instead of storing the start times of the individual titles. The more titles that are recorded on a inserted CD-record, the better the storage space is used, and the more the access times are reduced.

Abstract: A compact-disk player for playing a compact disk that carries data in a plurality of program blocks recorded on the disk. The program blocks are dividable into sections by indices which are stored for each program block. Each index has starting and ending times that are also stored. Any index within any program block may be selected, and an optical scanner scans the compact disk to be played. The amount to be skipped by the optical scanner to arrive at a position that corresponds to the selected index, is calculated from the stored starting and ending times.

Abstract: A tracking circuit for guiding a beam of light along data tracks of a recorded medium as compact disks and video disks, in which the recorded medium reflects a light beam onto a photodetector. The photodetector has an output voltage that is applied to a servo through a variable-gain amplifier. A compensation voltage is superimposed over the output voltage from the photodetector during the open state of the circuit to compensate off said voltages. This compensation voltage is varied until the sum of the output voltage from the photodetector and the compensation voltage attains a predetermined value. Thereafter the circuit is closed.

Abstract: A method for skipping tracks in apparatus playing back data that is readable from data-storage tracks on a recording medium by an optical scanner when a base of light is positioned on the tracks by a tracking circuit. The optical scanner is shifted from one data track to another by a skipping pulse during a track-skipping procedure, and is halted in place there by a braking pulse. The tracking circuit is opened not prior to the beginning of the skipping pulse and not later than the departure from the data-storage track. The optical scanner is braked by a first braking pulse of constant length and amplitude, but which is too small. A second braking pulse is produced with pulse characteristics dependent on the time that elapses until a predetermined point on the next data-storage is arrived at. The second braking pulse thereby halts the scanner in the middle of the next data-storage track.

Abstract: An arrangement for inserting and extracting a recorded medium in which a movable slidable member is slidable in directions into and out of said stationary housing member. The slidable member is provided with two nose-shaped elements that are spaced from one another. A single switch mounted on the stationary housing member is actuated by the nose-shaped elements when the slidable member moves in-and-out of the stationary housing member. The in-and-out motion of the slidable member is made dependent on the states of the single switch.

Abstract: In CD-players with a memory (S) having A storage locations for the storing of the titles recorded on a CD-record, it can occur that the number of titles C recorded on the CD-record exceeds the number of storage locations A in the CD-player.In order to keep the access times for individual titles low, the memory (S) is partitioned into a first part (T1), having B storage positions, and a second part T2, having A-B storage positions. The titles 1 to B are stored in sequence in the B storage locations of the T1 portion of memory S. The remaining titles are distributed to the A-B storage locations of the part (T2) such that, no continuing sequence with the first B titles is formed. For example, the remaining C-B titles may be distributed evenly in the second part (T2) of memory S.

Abstract: A servo loop arrangement for the reproduction of data from a record medium has interleaved pulse trains of opposite polarity pulses applied to it to add to the servo loop control signal which undesirably includes an offset voltage. The resultant increasing opposite polarity changes in the control signal in successive pulse train intervals are threshold detected. The numbers of opposite polarity pulses required to reach the threshold values are compared and any difference in number is converted to a compensation signal which is added to the servo loop to compensate for the offset voltage.