KR940007284B1 - Double side reproduct system for optical disk - Google Patents

Abstract

The double side reproduction system is for reproducing an optical disc which is inserted with its data surface to be upper or to be behind. The double side reproduction system includes a LD player having double side reproduction function, a focus error detector (2) for detecting focus error from a pick up signal generated by a pick-up signal detector (1), a focus add signal detector (3) for detecting focus add signal, a level divider (4) for detecting that current surface is data surface or not and the disc is in or out, a TTL level adjuster (8) for applying TTL level to a syscom (12) after adjusting TTL level when the surface is not data surface, and a CD switch and a LD switch (21,20) for detecting lead-in area of an LD or a CD.

Description

Double-sided playback system of optical disc

1 is an implementation circuit diagram of the present invention.

2 is a flowchart of a conventional optical disc reproducing apparatus.

3 is a flowchart of the present invention.

4 is a turntable chucking unit of the present invention.

5 is a waveform diagram of the present invention.

* Explanation of symbols for main parts of the drawings

1: pickup signal recognition unit 3: focus sum unit

4: Level separating circuit 8: TTL level adjusting circuit

12: ciscon micom 13: motor direction switching system

14: spindle motor 15: turntable

16 turntable chucking unit 17 disk

18: motor 20: LD switch

21: CD switch 22: Guide

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided reproduction system of an optical disc that enables double-sided reproduction automatically in an optical disc reproducing apparatus. In particular, the present invention relates to an optical disc reproducing apparatus for both LD (Laser Disc) and CD (Compact Disc). The CD is automatically played even if it is mounted in any direction.

In the conventional LD and CD optical disc reproducing apparatus, there is no problem in reproducing the LD in which the information is recorded on both sides, but reproducing is possible only when the mounting direction is considered in the reproducing of the CD in which the information is recorded on one side.

That is, in the case of a CD, the information side has recorded information side and the non-information side information is not recorded. Therefore, when the CD is deposited, the information side must be mounted so that the information side can be located on the pickup. In this case, there was a disadvantage that information reproduction is impossible.

In the present invention, in order to solve the above-mentioned disadvantages, in the LD player capable of double-sided reproduction, playback is possible only when the information side is directed to the pickup side when the CD is played. An information plane recognition means for recognizing the information plane of the disc, and a pickup transport means for moving the pickup toward the information plane when a non-information plane is mounted on the pickup, and a direction switching means for switching the direction of the motor for information plane recognition. It was equipped.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The present invention controls the drive of the spindle motor 14 for rotating the turntable 15 and the motor 18 for transporting the pickup 19 under the control of the ciscon micom 12. In the LD player capable of double-sided playback, the motor 18 is configured to be moved to the upper and lower surfaces of the disk 17 along the guide 22, the focus error in accordance with the pickup signal recognition of the pickup signal recognition unit 1 The focus error part 2 and the focus sum part 3 which detect a signal and a focus sum signal, and the focus sum signal of the said focus sum part 3 are checked and an information plane, a non information plane, or a disc is present. A level separating circuit 4 for judging?, A TTL level adjusting circuit 8 for adjusting the TTL level to be applied to the ciscon micom 12 when the level separating circuit 4 determines the non-information plane, and the guide 22 ) And lead-in zeros for CDs and LDs CD switch 21 and LD switch 20 for detecting the reverse.

The turntable chucking unit 16 for mounting the disk 17 to the turntable 15 is formed by cutting a portion as shown in FIG. This is to detect the lead-in area of the CD disc through the cut-out part because the lead-in area is large and different accordingly.

Prior to describing the operation and effect of the present invention with such a configuration, a description will be given of the prior art in which only a disc having an information surface can be played back.

First, when the reproduction command is received, the pickup signal recognition unit 1 generates the focus actuator driving signal as shown in FIG. 5 (a). Accordingly, the focus sum unit 3 and the focus error unit 2 generate the focus actuator driving signal. (b) (c) detects the focus sum and error signals, and the detection signals in the focus sum unit 3 and the focus error unit 2 are 0.4V and 0.3V, respectively, through the level separating circuit 4; In this case, the normal regeneration operation is performed by applying the focus OK signal as shown in FIG.

The above-mentioned reproduction is a case where the disc has an information plane as in the case of the LD disc. After the reproduction of the bottom surface of the disc having the information plane, the direction of the spindle motor 14 is switched as shown in the flowchart shown in FIG. After turning off the servo such as focus, tracking, and tilt, the motor 19 moves the pickup 19 along the guide 22 to the upper surface of the disk.

When the pickup 19 is transferred and the LD switch 20 is pressed, the servo is 'on' again, and the play progress direction is switched, and the disc is played back in the same manner as the bottom play.

However, the playback method described above only plays the disc by rotating the focus servo when the disc has an information plane. The disc has only one information plane, such as a CD. It must be mounted so that playback is possible, otherwise playback is impossible.

Therefore, in the present invention, the information surface is automatically reproduced even when the disc is mounted, regardless of the pickup position.

First, when the play command is issued by the scissor micom 12, the voltage level read from the focus sum unit 3 and applied to the level separating circuit 4 according to the pickup signal recognition by the pickup signal recognition unit 1 is the disk 17. There is a difference depending on the state of the.

That is, the focus sum unit 3 applies a voltage of 4 V or more to the level separation circuit 4 when the information surface of the disk 17 is read, and 0.3 V when the non-information surface is read. V or less is applied.

When the applied voltage of the focus summation unit 3 is recognized by the level separating circuit 4, if the voltage is 4V or more, it is an information plane, and if it is 3V or less, it is displayed normally. Since only one side is a disk, the disk signal is sent to the scissor microcomputer 12 via the TTL level adjustment circuit 8.

Then, in the scissor micom 12, the motor control command is transmitted to the motor direction switching system 13 to regenerate the disk. Accordingly, the motor direction switching system 13 may rotate the spindle motor 14 and the motor 10. Control.

In other words, in the case of a disk, the drive of the spindle motor 14 is switched and then the motor 18 is driven so that the pickup 19 is moved along the guide 22 to the top of the disk l7, but the The movement moves to the ground where the CD switch 21 is recognized.

If the CD switch 21 is checked, the driving of the motor 18 is stopped, the focus servo is locked again, and the information surface is reproduced.

At this time, the chucking portion 16 of the turntable 15 cuts a part as shown in FIG. 4 so that the lead-in area of the CD disc can be read out of the pickup 19.

That is, since the radius of the LD disc is larger than that of the CD disc, when the chucking portion 16 chucking the LD disc is used therein, the lead-in area of the CD disc is obscured by the chucking portion 16 so that the pickup 19 can read it. Therefore, as shown in FIG. 4, a portion is cut to read the lead-in area of the CD disc.

The present invention is described above with reference to the flowchart shown in FIG.

When the disc is LD, the disc is reproduced in the same manner as the conventional LD reproducing method. On the other hand, when the disc is a CD, the level separation circuit 4 detects the voltage level of the focus sum unit 3 and detects the non-information surface. After changing the direction of the servo, focus, tracking, tilt, etc. Servo 'off' and drive the motor 18 to move the pickup 19 along the guide 22 to the top and check whether the CD switch 21 is checked. To judge.

If the CD switch 21 is checked, the servo is 'on' and then the regeneration direction is reversed from the lower side, while the regeneration is performed in the same manner as the regeneration.

As described above, in the LD player capable of playing two people, even if a CD disc having information recorded on only one side is mounted regardless of the pickup position, the present invention automatically finds and plays the information surface, thereby providing convenience for use.

Claims (2)

Under the control of the ciscon micom 12, the motor turning system 13 controls the driving of the spindle motor 14 for rotating the turntable 15 and the motor 10 for feeding the pickup 19. The motor 18 is a double-sided reproducible LD player configured to be moved to the upper and lower surfaces of the disk 17 along the guide 22, and the focus error signal and the focus are determined in response to the pickup signal recognition of the pickup signal recognition unit 1. The focus error unit 2 and the focus sum unit 3 which detect the sum signal, and the focus sum signal of the focus sum unit 3 are checked to determine whether the information plane, the non-information plane, or the disc is not present. A level separating circuit 4, a TTL level adjusting circuit 8 for adjusting the TTL level and applying it to the scissor microcomputer 12 when the non-information surface is judged by the level separating circuit 4, and positioned in the guide 22; Detects the lead-in area of CD and LD Both sides of the optical disc reproduction system to the CD consisting of a switch 21 and the LD switch 20 in particular. 2. The double-sided reproduction system for an optical disc according to claim 1, wherein the chucking portion (16) which fixes the disc (17) is formed by cutting a part to the lead-in area of the CD.