JPH01113958A - System for reproducing disk - Google Patents

Abstract

PURPOSE:To always reproduce a signal regardless of the mounting direction of a disk by arranging a pick-up in a recording surface side and reproducing the signal when the disk where the signal is recorded to only one side surface is mounted to a turn table. CONSTITUTION:When a disk 3 to have a first surface where the signal is recorded and a second surface where the signal is not recorded is mounted on a turn table 2, the direction of the first surface is detected and when a pick-up 5 is only one, the pick-up 5 is moved to the first surface side. When pick-up 5 and 6 are arranged one by one on the turn table 2 and under the table 2, the pick-up 5, for example, to be arranged in the first surface side is selected. The reproducing is executed by the moved or selected pick-up 5. Thus, regardless of the mounting direction of the disk 3, the reproducing of the first surface can be executed.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a disc playback method suitable for use in a disc player capable of playing compact discs (including CD-V discs) and/or optical video discs. Regarding.

[Summary of the invention]

In the present invention, when a disc with signals recorded only on one side is mounted on a turntable, the pickup is placed on the recording surface side regardless of the mounting direction of the disc,
Play the signal.

[Background technology]

Compact discs have signals recorded on only one side.
No signal is recorded on the other side.

Since the pickup is usually placed on the turntable side, compact discs are loaded with the signal recording side facing down (turntable side). If you accidentally load the disc with the non-recording side facing down, this will be detected and the disc will be unloaded.

(rjJWt points that the invention seeks to solve) Conventional players play only when loaded with the signal recording side facing down, so the loading (installation) direction must be confirmed in advance. The operation was poor.

The present invention was made in view of this situation, and is intended to enable signal reproduction at all times regardless of the direction in which the disc is mounted.

[Means for solving problems]

The disc playback method of the present invention detects the first side when a disc having a first side on which a signal is recorded and a second side on which no signal is recorded is mounted on a turntable. , the pickup is moved to the first side, or the pickup on the first side is selected, and the first side is reproduced regardless of the mounting direction of the disc.

[Effect]

When the disc is loaded onto the turntable, the orientation of the first surface is detected.

If there is only one pickup, the pickup is transferred to the first surface side. When one pickup is placed on the top and one on the top of the turntable, the pickup placed on the first surface side is selected. Then, reproduction is performed by the transport or the selected pickup.

Therefore, the first side can be reproduced regardless of the mounting direction of the disc.

〔Example〕

FIG. 1 is a block diagram of a disc player of the present invention capable of playing both compact discs and optical video discs. In the figure, 1 is a spindle motor, 2 is a turntable rotated by the motor 1, and 4 is a clamper that clamps a disk 3 placed on the turntable 2.

When the disc 3 is loaded onto the turntable 2, the control circuit 12 comprising a microcomputer or the like performs a pickup selection operation according to a flowchart as shown in FIG. 2, for example.

When a playback surface is specified by operating the input means 13, the control circuit 12 turns on the focus servo of the pickup for the specified surface.

For example, when the designated side is the A side, the pickup 5 placed on the lower side (turntable side) of the disc 3 is selected, and when the B side is specified, the pickup 6 placed on the upper side is selected and its focus is Servo loop is turned on. When there is only one pickup, the pickup is transferred to the designated surface side by the driving means 7 (or 8), and the focus servo loop is turned on there.

When the focus servo loop is locked, disk 3
The innermost control track is played. The reproduced signal output from the pickup 5 (or 6) is input to the amplifier circuit 10 via the switch 9, which is switched by the control circuit 12 in accordance with the designated surface, and is amplified. The output of the amplifier circuit 10 is input to a demodulation circuit 11 and demodulated. The control circuit 12 reads TOC information from this demodulated output.

This TOC information includes, for example, a compact disc.

It includes an identification code for the video disc, side A or B of the video disc, etc.

If a compact disc (CD) is loaded, there is only one recording surface, so if the start of playback is input, playback of that side will be started.

Not a compact disc (it's a video disc)
In this case, if the playback side matches the specified side, the playback process is performed, and if they do not match, the selection of insects for Pickup 5 (or 6) is stopped and Pickup 6 (or 5) on the opposite side is selected. , its focus servo loop is turned on.

Error handling is performed when the servo loop does not lock,
When locked, TOC information is read. When the playback surface matches the designated surface, playback processing is performed, and when they do not match, error processing is performed.

If the focus servo of the first designated surface does not lock, the focus servo of the pickup on the opposite side is turned on. If the servo loop does not lock, error handling is performed, and if it locks, the TOC information is read. If the disc is a compact disc or a video disc and the playback surface matches the specified surface, playback processing is performed, and if they do not match, error processing is performed.

If the disc loaded in this way is a compact disc, no matter which side the recording side is loaded on, or whether the non-recording side is designated as the playback side, the recording side will not play. be exposed.

Furthermore, no matter which side of the video disc is loaded, playback is always performed from the designated side, either side A or side B.

If no particular reproduction surface is specified, the focus servo of one side pickup (for example, the lower pickup 5) is first turned on. When the servo is locked, the TOC information is read, and when the disc is a compact disc or side A of a video disc, playback processing is performed.

When it is the B side of the video disc, the focus servo of the opposite pickup (upper pickup 6) is turned on, and if the servo does not lock, error processing is performed.

T when the servo is locked.

The C error information is read, and if the playback side is not the A side, error processing is performed, and if it is the A side, playback processing is performed.

If the focus servo of the lower pickup 5 does not lock at first, the focus servo of the upper pickup 6 is turned on, and if the servo does not lock, error processing is performed. When the servo is locked, the TOC information is read, and if it is a compact disc or side A of a video disc, playback processing is performed. If it is not side A of the video disc, error processing is performed.

Therefore, even if no particular playback surface is specified, the recording surface of the compact disc is played regardless of the loading direction, and playback is started from side A of the video disc.

The reproduction output of the pickup 5 or 6 is input to the demodulation circuit 11 via the switch 9 and the amplifier circuit 10.
A reproduced audio signal and a reproduced video signal are outputted from the output terminal.

In order to enable playback by the pickup 6 disposed on the opposite side of the turntable 2, the outer diameter of the damper 4 must be equal to or smaller than that of the turntable 2.

Furthermore, in the above description, the video disc can be played from both sides, but it is also possible to play back both sides when two compact discs are mounted on the turntable 2 with the recording side facing outward. .

〔effect〕

As described above, according to the present invention, since the pickup can be placed on either the upper or lower side of the disc, it is possible to play a disc on which only one side is the recording surface, regardless of the mounting direction. .

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a disc player of the present invention, and FIG.
The figure is a flowchart. 1...Spindle motor 2...Turntable 3...Disk 4...Clamper 5.6...Pickup 7.8...Drive means 9...Switch 10...Amplification circuit 11. ... Demodulation circuit 12 ... Control circuit 13 ... Input means Patent applicant Pioneer Corporation

Claims (1)

[Claims] When a disc having a first side on which a signal is recorded and a second side on which no signal is recorded is mounted on a turntable, the first side is detected, and the first side is or select the pickup on the first side, and move the pickup to the first side regardless of the mounting direction of the disk.
A disc playback method characterized by playing back sides.