JPH06325380A - Disk reproducing device - Google Patents

Abstract

PURPOSE:To provide a disk reproducing device capable of holding double speed precision in a high speed reproducing function to a fixed level by using an absolute time recorded on a disk. CONSTITUTION:The information recorded on the disk 4 is read by a reader 5 while following up the track of the disk 4 rotated with a rotation driving device 7 by a tracking servo 19 means, and the reader 5 is moved in two ways of a normal reproducing speed and a high speed reproducing speed in the radial direction of the disk 4 by a moving device 6. Then, the high speed reproducing function repeating the operation turning off the tracking servo circuit 19 and moving the reader 5 in the radial direction of the disk at high speed and the operation of turning on the tracking servo circuit 19 and reproducing for a prescribed time by the reader 5 is controlled by a control part 2, and only a reproducing time at a high speed reproducing time is revised by calculating the substantial position of the reader 5 from the absolute time in the disk 4 by the control part 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc reproducing apparatus, and more particularly to a disc reproducing apparatus capable of switching disc reproduction between normal reproduction and high speed reproduction.

[0002]

2. Description of the Related Art Conventionally, there is a disk reproducing apparatus such as a CD player capable of normal reproduction and high-speed reproduction such as fast-forward and fast-reverse.

Further, the high-speed reproducing function in such a disk reproducing apparatus is realized by alternately performing a normal reproduction and an arbitrary number of track jumps continuously as shown in FIG.

The double speed value consisting of the reproduction time (Xmsec) and the number of track jumps (Y) of the normal reproduction by the pickup device as the reading device is, for example, a case where one minute of music is reproduced in 30 seconds by fast-forward reproduction. 2x speed of 70msec, 2 lines, 1 minute of song by fast-forward playback
75 msec, 3 at 3x speed, such as when playing back at 0 seconds
It is set to 100 msec, 25 tracks, etc. at 30 times speed, such as when a 1-minute song is played back in 2 seconds by fast-forward playback.

[0005]

However, in the disc reproducing apparatus constructed as described above, the radial movement of the pickup device is always performed by a predetermined number of tracks regardless of the position of the pickup device. It is set. Therefore, since the disk rotates at a constant linear velocity, the double speed value toward the outer circumference of the disk becomes about twice as fast as the double speed value toward the inner circumference of the disk. Was occurring.

Therefore, as disclosed in Japanese Examined Patent Publication No. 40792/1992, the number of tracks to be jumped is changed according to the position of the pickup device to make the double speed accuracy uniform during high-speed reproduction according to the pickup device. Is being considered.

However, in the case in which the number of tracks to be jumped differs depending on the position of the pickup device, there is a new problem that it is not practical because the speed cannot be finely adjusted.

In view of the above situation, it is an object of the present invention to provide a disc reproducing apparatus which can keep the double speed precision in the high speed reproducing function constant by utilizing the absolute time recorded on the disc. is there.

[0009]

In order to achieve the object, the present invention provides a reading device for reading information recorded on a disc rotated by a rotary drive device and the reading device for following the track of the disc. Controls a tracking servo means, a high-speed reproducing function for repeating the operation of turning off the tracking servo means to move the reading device at a high speed in the radial direction of the disk, and turning on the tracking servo means to reproduce the reading device for a predetermined time. A disc reproducing apparatus including a control unit for controlling the reading position, the position detecting unit detecting a substantial position of the reading unit, and the changing unit changing the predetermined time based on a detection result of the position detecting unit. That is the main point.

[0010]

In such a structure, there is a high-speed reproducing function in which the operation of turning off the tracking servo means to move the reading device at high speed in the disk radial direction and the operation of turning on the tracking servo means to repeat the reproduction for a predetermined time by the reading device are repeated. The control unit controls the position detecting unit to detect the substantial position of the reading device, and the changing unit changes the predetermined time based on the detection result of the position detecting unit.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a disc reproducing apparatus of the present invention will be described with reference to the drawings.

In FIG. 1, a disc reproducing device 1 includes a control device 2 such as a microprocessor, an operating portion 3 having various operating functions such as a play button and a stop button (not shown), a fast forward button and a fast reverse button, and a disc. 4, a pickup device 5 as a reading device for reading the recorded information, a moving device 6 for moving the pickup device 5 in the radial direction of the disc 4, a rotary drive device 7 for rotating the disc 4, and a control circuit 8. I have it.

The control circuit 8 includes a drive circuit 9,
Thread servo circuit 10, tracking servo circuit 1
1, focus servo circuit 12, processing circuits 13, 14,
15, 16, voltage control oscillator 17, CLV servo circuit 1
8, tracking servo circuit 19, low-pass filter 2
0, a focus servo circuit 21, a track counter circuit 22, an EFM modulation circuit 23, a signal processing circuit 24, and a timer counter 25.

The pickup device 5 inputs (I1) the number of tracks read from the disk 4 to the control device 2 via the track counter circuit 22. In addition, the pickup device 5 uses the EF to record information recorded on the disc 4.
After selecting the bit pattern by the M modulation circuit 23,
The signal is processed by the signal processing circuit 24 and input (I2) to the control device 2.

The control device 2 calculates the current position of the pickup device 5 based on the absolute time (= input I1) previously recorded on the disk 4, for example. At this time, the time recorded on the disk 4 is converted into minutes. In addition, the control device 2
Is a control signal O1, O2, O3, O4 to the processing circuits 13, 13, 15, 16 and the track counter circuit 22 based on the operation from the operation unit 3 and the input signals I1, I2.
Output N. Further, when the high-speed reproduction signal is output from the operation unit 3, the control device 2 changes the reproduction time while keeping the number of track jumps of the disk 4 constant according to the current position of the pickup device 5, thereby achieving the double speed accuracy. Is set to keep constant.

For example, as shown in FIG. 2, when the double speed value near the innermost periphery of the disk 4 is double speed when the reproduction time = 70 msec and the number of track jumps = 2, the pickup device 5 is used. Is a reproduction speed = 70 msec + (absolute time converted into minutes × 2) msec, the number of track jumps, as shown in FIG. 3, for realizing the same double speed as in the vicinity of the innermost circumference in any place. = 2 lines are set.

Therefore, as shown in FIG. 4, apparent fast-forward when the pickup device 5 is located on the inner peripheral side of the disk 4 and when the pickup device 5 is located on the outer peripheral side of the disk 4. The playback speed is constant.

FIG. 5 is a flow chart showing a control example of such a control device 2. It should be noted that this flow chart is based on the premise that the high-speed reproduction function start processing is performed when the disk 4 is in the normal reproduction state.

(Step 1) In Step 1, the absolute time (input signal I2) recorded on the disk 4 is calculated by the controller 2
Reads, and the time x obtained by converting the read time into minutes is obtained.

(Step 2) In Step 2, based on the time x converted into minutes in Step 1, the addition reproduction time X2
Ask for.

(Step 3) In step 3, the reproduction time on the outer peripheral side of the disk 4, that is, the normal reproduction time X1 + the additional reproduction time X2 is stored in the timer counter 25.

(Step 4) In step 4, the timer counter 25 counts X1 + X2 hours while the recording information is read by the pickup device 5.

(Step 5) In Step 5, whether or not the reproduction of the reproduction time X1 + X2 is completed is determined by the timer counter 2
It is determined by the count time of 5, and if it is not executed, it loops to step 4, and if it is executed, it moves to step 6.

(Steps 6 to 8) In Step 6, it is judged whether or not the operation signal for high speed reproduction from the operation unit 3 is fast forward, and if it is fast forward, the process proceeds to Step 7 to track Y tracks. If the jump is executed forward and is not fast forward, that is, if it is fast reverse, the process moves to step 8 to execute Y track jumps backward, and when this jump is executed, loops to step 1. To be done.

[0025]

As described above, in the disc reproducing apparatus of the present invention, the position detecting means for detecting the substantial position of the reading device, and the high speed reproduction based on the detection result of the position detecting means. By providing the changing means for changing only the reproduction time at the time, the double speed precision in the high speed reproduction function can be kept constant by utilizing the absolute time recorded on the disc.

[Brief description of drawings]

FIG. 1 is a block diagram showing a disc reproducing apparatus of the present invention.

FIG. 2 is an explanatory diagram showing a state of high speed reproduction in the vicinity of the inner circumference of the disc.

FIG. 3 is an explanatory diagram showing a state of high speed reproduction in the vicinity of the outer circumference of the disc.

FIG. 4 is an explanatory diagram comparing the inner circumference side and the outer circumference side of the disk during high speed reproduction.

FIG. 5 is a flow chart showing a control example of the control device.

FIG. 6 is an explanatory diagram showing a state of high speed reproduction in a conventional disc reproducing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Disc reproducing device 2 ... Control device 4 ... Disc 5 ... Pickup device (reading device) 19 ... Tracking servo circuit

Claims (1)

[Claims] 1. A reading device for reading information recorded on a disc rotated by a rotation drive device, a tracking servo means for causing the reading device to follow a track of the disc, and the reading by turning off the tracking servo means. A disc reproducing apparatus comprising: a control unit for controlling a high-speed reproducing function for repeating the operation of moving the apparatus at a high speed in the radial direction of the disk and turning on the tracking servo means to reproduce for a predetermined time by the reading apparatus. 2. A disc reproducing apparatus, comprising: a position detecting means for detecting a substantial position of the position detecting means; and a changing means for changing the predetermined time based on a detection result of the position detecting means.