JPH01122084A - Optical disk device - Google Patents

Abstract

PURPOSE:To obtain a stable characteristic by detecting an ID signal, synchronizing with a track jump start timing pulse to be generated after a fixed time and executing a jump. CONSTITUTION:A track actuator 13, a tracking error signal detector 14, a phase compensating filter 10, analog switch 11 and an amplifier 12 constitute a tracking servo loop. An ID information (a) from a medium generates a timing pulse (b) after the fixed time by a track jump start timing generator 1, a synchronization with a track jump request signal (c) is obtained by a gate signal generator 4 and a trigger pulse (e) and the gate signal (d) of the switch 11 are generated. By the pulse (e), a jump pulse generator 7 generates accelerating/ reducing pulse (f) from driving the track jump of the actuator 13, the loop is opened by the signal (d) through the switch 11, circuits of the amplifier 12, etc., are connected to the signal (f) side, one track jump is executed and the loop is closed again by the switch 11. Thus, a stable servo characteristic can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical disc device, and particularly to start timing control at the time of track jump.

[Conventional technology]

Conventionally, this type of optical disk device opens a tracking servo loop at an arbitrary time during a track jump, sends acceleration and deceleration pulses for track jump to the tracking actuator, and starts the tracking servo when the light beam has moved one track. It was closed.

[Problem that the invention seeks to solve]

However, in the optical disk device, an ID signal 21 is recorded on the medium 20 as shown in FIG. When the error signal is disturbed, the tracking servo loop may be opened or closed during a track jump, and there is a drawback that stability cannot be maintained when the tracking servo loop is closed after a track jump.

[Means for solving problems]

The present invention provides an optical disk device equipped with a tracking servo loop that processes a tracking error signal from an optical head to drive a tracking actuator. acceleration/deceleration pulse generating means for generating acceleration/deceleration pulses for jumping, and opening the tracking servo loop after the predetermined time from detection of the ID signal to send the acceleration/deceleration pulses to the tracking actuator; and a switch circuit that closes the servo loop again, and passes the ID signal during a track jump.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 and FIG. 2 are a block diagram and a timing chart, respectively, of an embodiment of the present invention. 1 and 2 only show the parts related to the tracking servo loop and track jump control system of the optical disc device.

The error signal g from the tracking actuator 13 and the tracking error signal detector 14 is passed through the phase compensation filter 10.
and then via the analog switch 11,
A tracking servo loop is formed by creating a loop that drives the tracking actuator 13 via the amplifier 12. The ID information a detected from the medium is
The track jump start timing pulse generator 1 is entered, and the pulse generator 1 generates a timing pulse b after a time tl from ID detection as shown in FIG. This time t
, has the following relationship.

t3 proboscis t 1+I/2 (t2). However, time t3 is the interval between ID signals, and time t2 is the time during which the tracking servo loop is open during track jump.

The track jump request signal C is synchronized with the tracking start timing pulse b by the gate signal generator 4, and generates a trigger pulse e and a gate signal d for the analog switch 11. In response to the trigger pulse e, the jump pulse generator 7 generates an acceleration/deceleration pulse f for driving the tracking actuator 13 for a track jump for a certain period of time. This pulse f enters the analog switch 11, and the track servo loop is opened by the gate signal d (the tracking servo loop is opened when the gate signal d is at a high level), and a circuit such as an amplifier 12 is connected to the signal f side. Been, 1
After the track jump is completed, the analog switch 11 closes the servo loop again. At this time, since the track jump is executed across the ID signal, when the servo loop is closed, there is no disturbance of the track error signal due to the ID signal, so stable servo characteristics can be obtained, and a device with stable track jump characteristics can be obtained. can be realized.

〔Effect of the invention〕

As explained above, the present invention detects an ID signal from a medium, generates a track jump start timing pulse after a certain period of time, and performs a track jump in synchronization with this pulse.
passes, and when the track jump ends, track servo is applied using a straightforward track error signal that is not affected by the ID, which has the effect of providing stable track jump characteristics.

[Brief explanation of the drawing]

1 and 2 are a block diagram and a timing chart of each signal of an embodiment of the present invention, respectively, and FIG. 3 is a diagram showing an ID signal on an optical disk medium. DESCRIPTION OF SYMBOLS 1... Track jump σ day timing pulse generator, 4... Gate signal generator, 7... Jump pulse generator, 10... Phase compensation filter, 11...
Analog switch, 12...Amplifier, 13...Tracking actuator, 14...Track error detector, a...Media ID signal, b...Track jump start timing pulse, C... Track jump request pulse, d...analog switch gate signal, f...
...Acceleration/deceleration pulse, g...Track error signal.

Claims (1)

[Claims] In an optical disk device equipped with a tracking servo loop that processes a tracking error signal from an optical head to drive a tracking actuator, when a track jump request is made, a track jump is performed after a certain period of time after detection of the ID signal of the medium. acceleration/deceleration pulse generation means for generating acceleration/deceleration pulses; and opening the tracking servo loop after the predetermined time from detection of the ID signal to send the acceleration/deceleration pulses to the tracking actuator and then restarting the tracking servo loop. An optical disc device characterized in that the optical disc device includes a switch circuit that closes the track, and passes the ID signal during a track jump.