JPH08171735A - Offset adjusting device - Google Patents

Abstract

PURPOSE: To provide an offset adjusting device in which the starting time of disk recording/reproducing apparently shortened by simultaneously performing starting of a rotary mechanism and offset adjusting in an optical recording/ reproducing device. CONSTITUTION: A command issuing means 10 issues an operation command to a rotational means 2 for starting the operation and simultaneously issues an operation command to an offset adjusting means 9. The offset adjustment control means 9 compares the output of an error signal generating means 6 with a reference value and when a difference thereof (an offset value) exceeds a prescribed range, the offset correction data is outputted to a bias voltage injecting means 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offset adjusting device for correcting an offset of a control system error signal in an optical disk device.

[0002]

2. Description of the Related Art In recent years, an increasing number of optical disc devices automatically adjust a control system error signal each time the power of the device is turned on.

As a conventional offset adjusting device, for example, as disclosed in Japanese Patent Application Laid-Open No. 04-176026, there is one which injects a DC component having a polarity opposite to that of the offset and the same value as the offset into the signal. Can be mentioned.

[0004]

However, in the above-mentioned conventional configuration, there is a problem that the timing for executing the offset adjustment is not mentioned. For example, if the rotating mechanism is started after performing offset adjustment, both the offset adjustment processing time and the time for the rotating mechanism to reach the specified number of rotations are simply added as the disk playback / recording start time. Will be done.

The present invention solves the above-mentioned conventional problems, and provides an offset adjusting device capable of shortening the apparent adjustment processing time by performing the offset adjustment simultaneously with the activation of the rotating mechanism. To aim.

[0006]

In order to achieve this object, an offset adjusting apparatus of the present invention comprises a rotating means for rotating an optical disk having a predetermined track form, and an offset adjusting control means for carrying out processing for obtaining an offset correction value. When,
It has a configuration of command issuing means for issuing an operation command to the rotating means and the offset adjustment control means.

[0007]

With the above structure, the command issuing means issues an operation command to the rotating means to start the activation of the rotating means. Then, the operation command is issued to the offset adjustment control means and the offset adjustment is performed without waiting for the rotation means to reach the predetermined number of rotations, thereby realizing the offset adjustment in which the apparent adjustment processing time is shortened. .

[0008]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an offset adjusting apparatus of the present invention. In FIG. 1, reference numeral 1 is an optical disk having a predetermined track shape, 2 is a rotating means for rotating the optical disk 1, and 3 is a light beam focused on a recording / reproducing surface of the optical disk 1 to form a light spot. An optical pickup for detection 4, a focus actuator for focusing the light spot, 5 a tracking actuator for moving the light spot in the disk radial direction,
6 is an error signal generating means for generating a control system error signal from the output of the optical pickup 3, 7 is a control means for controlling the rotating means 2 and the optical pickup 3, and 8 is an output for converting the output of the offset adjustment control means 9 into a bias voltage. Error signal generating means 6
Bias voltage injecting means for injecting into the device, reference numeral 9 denotes an offset adjusting control means for performing processing for obtaining an offset correction value according to the difference between the output of the error signal generating means 6 and the reference value'a '
Is a command issuing means for issuing a command to the optical pickup 3, the control means 7 and the offset adjustment control means 9, and 11 is a rotation speed reaching signal to the command issuing means 10 when the rotation means 2 is rotating at a predetermined rotation speed. It is a rotation speed determination means for outputting.

The operation of the offset adjusting apparatus of the present embodiment having the above-described structure will be described below in the case of performing the offset adjustment when reproducing the optical disk. Figure 2
Is a flowchart describing this operation.
To F211.

First, the command issuing means 10 issues a rotation mechanism start command to the control means 7 and causes the control means 7 to start the rotation means 2 (F201). Immediately after issuing this command, an offset activation command is issued to the offset adjustment control means 9 to start offset adjustment (F202). The offset adjustment control means 9 first takes in the focus error signal from the error signal generation means 6, compares the focus error signal with the reference value'a ', and when the difference exceeds a predetermined range, the offset adjustment data is obtained. The calculated value is output to the bias voltage injecting means 8, and the offset of the focus error signal is adjusted. Then, for the tracking error signal, offset adjustment of the tracking error signal is performed in the same manner. When these offset adjustments are completed, the offset adjustment control means 9 outputs an adjustment end signal to the command issuing means 10.

Upon receiving the adjustment end signal (F203), the command issuing means 10 issues a laser-on command to the optical pickup 3 to turn on the laser (F204). Then, a focus control ON command is issued to the control means 7, the focus actuator 4 is operated from the control means 7, and focus control is executed (F205). When the control means 7 confirms that the focus control is completely applied,
The focus control lock signal is output to the command issuing means 10. Upon receiving the focus control lock signal (F206), the command issuing unit 10 issues a tracking control ON command to the control unit 7, causes the control unit 7 to operate the tracking actuator 5, and executes tracking control (F207). After confirming that the tracking control is completely applied, the control means 7 outputs a tracking control lock signal to the command issuing means 10.

When the command issuing means 10 receives the tracking control lock signal (F208), the rotation speed determining means 1
Check whether there is a rotation speed arrival signal output from 1 (F
209). If the rotation speed reaching signal has been issued, a rotation control ON command is issued to the control means 7 (F210), and the control means 7 executes rotation control at a constant angular velocity or a constant linear velocity.

FIG. 3 is a characteristic diagram showing the number of revolutions, the time, and the respective processing times from the activation of the rotation means 2 to the time when the rotation control can be performed. In FIG. 3, MOK is the minimum rotation speed at which rotation control can be applied, and Tmok is the time until the rotation speed reaches MOK. Since at least Tmok is required to reproduce and record the disc, it can be seen that the offset adjustment and laser-on processing as described above can be performed using this time.

As described above, according to this embodiment, the offset adjustment can be performed while the rotating means reaches the predetermined number of rotations by starting the offset adjusting in parallel with the start of the activation of the rotating means. Even if the offset adjustment is added, the disc can be started in a time equivalent to the start time of the disc reproduction when the adjustment is not performed.

In the present embodiment, the offset adjustment of the focus error signal and the tracking error signal is performed, but any signal of the control system may be adjusted.

Further, in the present embodiment, the offset adjustment is performed at the time of reproducing the optical disk, but it may be performed at the time of recording.

Further, each means in this embodiment can be realized by any method of hardware, software, analog processing, digital processing.

[0019]

As described above, according to the present invention, the command issuing means issues the operation command to the rotating means to start the activation of the rotating means, and at the same time, the operation command is issued to the offset adjusting control means to perform the offset adjustment. By doing so, it is possible to realize the offset adjustment in parallel with the activation of the rotating means, and it is possible to realize the offset adjustment in which the apparent disk reproducing / recording starting time is shortened.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an offset adjusting device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the offset adjusting apparatus in the embodiment of the present invention.

FIG. 3 is a characteristic diagram of the rotation speed and time of the rotating means.

[Explanation of symbols]

 2 rotation means 3 optical pickup 6 error signal generation means 8 bias voltage injection means 9 offset adjustment control means 10 command issuing means 11 rotation speed determination means

Claims (2)

[Claims] 1. Rotating means for rotating an optical disk having a predetermined track shape, an optical pickup for converging a light beam on a recording / reproducing surface of the optical disk to form a light spot, and detecting reflected light thereof, An error signal generating unit that outputs a relative position error or a focus position error between the control target position and the light spot from the output of the optical pickup, and an offset correction value according to the difference between the output of the error signal generating unit and the reference value. Offset adjustment control means for performing the required processing, bias injection means for converting the output of the offset adjustment control means into a bias voltage and injecting it into the error signal generation means, and start of operation for the rotation means and the offset adjustment control means. A command issuing means for issuing a command for prompting the Husset adjustment device. 2. A rotation speed determination means for determining whether the rotation means is operating at a predetermined rotation speed or more and outputting the result to a command issuing means is provided, and the rotation is performed after the command issuing means performs offset adjustment. The offset adjusting device according to claim 1, wherein the rotation control is performed after confirming that the means is operating at a predetermined rotation speed or more.