JPH11328710A - Laser output setting method for optical disk recording/ reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform precisely detective operation of a signal level accompanying recording/reproducing operation of a test signal even when a wobbly surface and eccentricity exist in a rotation characteristic of a disk by recording the test signal ranging to peripheral revolution of a track. SOLUTION: The test signal is recorded on a first peripheral revolution track of a trial write area by a prescribed laser output A. At this time, when the disk is rotated once is decided, the test signal is recorded on a second peripheral revolution track by the laser output B different from the laser output A. Then, when the disk is rotated once is decided, the levels of the test signal recorded on the first peripheral revolution track and the test signal recorded on the second peripheral revolution track are detected, and the laser output C is set based on the detected signal level. By reproducing the recorded test signal, and detecting the level, a relation between respective laser outputs and the recording characteristic of the disk is detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk recording / reproducing apparatus configured to record a signal on a disk by a laser radiated from an optical pickup and to reproduce a signal recorded on the disk by the laser. About.

[0002]

2. Description of the Related Art Disk players which read signals recorded on a disk by using an optical pickup have become widespread. Recently, in addition to a reproducing function, a disk irradiated by a laser emitted from the optical pickup has been used. An optical disk recording / reproducing apparatus configured to record a signal on the optical disk has been commercialized.

In such an optical disk recording / reproducing apparatus, a pit is formed on a disk by a laser. However, if the laser output is not optimal, the pit shape may be too large or too small. Will do. Therefore, a disk used in such an optical disk recording / reproducing apparatus is provided with a test writing area on the innermost side, and after recording a signal in the test writing area, reproducing the signal, and detecting the reproduced signal. Is configured to set a laser output for recording by using such a technique. For example, such a technique is disclosed in Japanese Patent Application Laid-Open No. 6-76288.

[0004]

The recording operation of the test signal in the test writing area is performed on a frame-by-frame basis or by time control. There is a problem that the operation is adversely affected, and an accurate laser output setting operation cannot be performed.

An object of the present invention is to provide a laser output setting method which solves such a problem.

[0006]

According to the present invention, a test signal is recorded at different laser outputs on the first track and the second track in the test writing area provided on the disk, and is recorded on the first track and the second track. A laser output is set based on the level of the signal obtained, a test signal is recorded on a third track by the set laser output, and the level of the signal recorded on the third track is determined. The output is set.

[0007]

FIG. 1 is a flowchart showing a laser output setting method according to the present invention, and FIG. 2 is a block circuit diagram showing an embodiment of an optical disk recording / reproducing apparatus according to the present invention.

In FIG. 2, reference numeral 1 denotes a turntable which is rotated by an electric motor 2 and on which a disk 3 is mounted, and 4 denotes a signal surface of the disk 3 which incorporates a laser element for irradiating the disk 3 with a light beam. This is an optical pickup in which a photodetector that receives a light beam that is reflected more is incorporated.

Reference numeral 5 denotes an RF signal amplifying circuit for amplifying an RF signal obtained from the photodetector of the optical pickup 4 and shaping the waveform, and 6 denotes an optical signal based on the signal obtained via the RF signal amplifying circuit 5. Focusing control for focusing the light beam of the pickup 4 on the signal surface of the disk 3, tracking control for causing the light beam to follow a signal track on the signal surface, and track jump operation for moving the light beam to an adjacent track or the like. This is a pickup control circuit to be performed.

Reference numeral 7 denotes a digital signal processing circuit which performs digital signal processing of signals output from the RF signal amplifier circuit 5 and performs demodulation of various signals, and 8 denotes a digital signal processed by the digital signal processing circuit 7. This is a signal reproducing circuit to which a signal is input. When the information recorded on the disk 3 is an audio signal, the signal is converted into an analog signal and then output to an amplifier or the like, and when the signal is a data signal such as computer software. Has a function of outputting a digital signal to a computer device as it is.

Reference numeral 9 denotes an operation switch in which a switch for each operation operated when switching the operation of the optical disk recording / reproducing apparatus is incorporated. 10 denotes a signal which is demodulated by the digital signal processing circuit 7 and is inputted. This is a system control circuit that performs various control operations according to the operation of the operation switch 9. 11 is the system control circuit 1
This is a motor drive circuit whose operation is controlled by 0, and has the function of controlling the rotational drive of the motor 2.

A laser driving circuit 12 for driving a laser element incorporated in the optical pickup 4;
Reference numeral 13 denotes a laser output setting circuit whose operation is controlled by the system control circuit 10. The laser output setting circuit 13 is configured to set the laser output by controlling the laser drive circuit 12. The laser drive circuit 1 receives a recording signal and responds to the signal.
2 is a signal recording circuit for recording a signal on the disk 3 by controlling the laser irradiation operation of the disk 2.

A signal level detection circuit 15 receives a signal output from the RF signal amplification circuit 5 and detects the level of the signal. The detection level is input to the system control circuit 10. It is configured.
Reference numeral 16 denotes a rotation detection circuit to which a pulse signal obtained from a hall element or the like incorporated in the electric motor 2 in accordance with the rotation driving operation of the electric motor 2 is inputted, and which is turned on by counting the number of inputted pulse signals. Table 1 is 1
It is configured to detect rotation and output a detection output to the system control circuit 10.

In such a circuit configuration, when the disk 3 is inserted into the mounting portion of the disk in order to perform a signal recording operation, a laser output setting operation is performed. The operation of setting the laser output is performed by performing an operation of recording a test signal in a test writing area provided on the innermost peripheral side of the disk 3 and an operation of reproducing the recorded test signal. Will be described later.

The laser output is set by the operation of recording and reproducing the test signal in the test writing area, and the operation of recording the signal in the data signal recording area provided on the disk is started by the laser output thus set. However, when a signal recording operation is being performed, the value of the drive current supplied from the laser drive circuit 12 to the laser element is changed by monitoring the change in the light reflected from the disk 3 to constantly perform the recording operation. It is configured to adjust the laser output to be optimal.

As described above, the optical disk recording / reproducing apparatus according to the present invention is configured. Next, the reproducing operation in the circuit configured as described above will be described. Operation switch 9
Is operated, a control operation for a reproduction operation by the system control circuit 10 is started. When such a reproducing operation is performed, a driving current for obtaining a laser output for performing a signal reading operation is supplied to the laser element incorporated in the optical pickup 4 from the laser driving circuit 12. Is set to

When the control operation for such a reproduction operation is started, the rotation control operation of the electric motor 2 by the electric motor drive circuit 11 is performed, and the focus control operation and the tracking control operation of the optical pickup 4 are started. The operation of reading a signal from the disk 3 by the optical pickup 4 is started. The signal read by the optical pickup 4 is input to a digital signal processing circuit 7 through an RF signal amplification circuit 5 to perform a signal demodulation operation. When signal processing is performed by the digital signal processing circuit 7 to extract information data, the information data is subjected to signal processing such as error correction and then applied to the signal reproduction circuit 8.

When the information data read from the disk 3 is an audio signal, the signal reproducing circuit 8 converts the information data into an analog signal and outputs the analog signal to an amplifier or the like. In this case, the digital signal is output as it is to the computer device.

As described above, the reproducing operation in this embodiment is performed. Next, the signal recording operation will be described. When the recording disk 3 is inserted into the mounting portion of the disk, an operation of setting a laser output is performed by an operation of recording and reproducing a test signal in a test writing area described later.

When the laser output value is set by the operation of recording the test signal in the test writing area and the operation of reproducing the test signal, the operation of recording the signal input from the signal recording circuit 14 is started. Such a signal recording operation is performed on a data signal recording area provided on the disk 3.

In the state where such a recording operation is being performed,
Since the temperature of the optical pickup 4 changes, the output of the laser and the wavelength of the laser change, and the recording characteristics for the disk 3 change. When the recording characteristics for the disk 3 change, the light reflected from the disk surface changes, so that the laser output value set by the laser output setting circuit 13 to correct the change is changed. Therefore, the signal recording operation on the disk 3 can be performed continuously with the optimum laser output value.

The signal recording operation is released by operating the recording stop switch provided on the operation switch 9, but the recording operation is terminated by the position information indicating the signal recording position and the like. It is configured to complete by recording data or the like at a predetermined position. That is, a reproduction operation of a desired signal can be started by using such position information data, and a setting operation of a position at which a next recording operation is started can be performed.

The signal recording operation is performed as described above. Next, the laser output setting method according to the present invention will be described with reference to the flowchart shown in FIG.
When the recording disk is mounted on the disk mounting portion, the operation of setting the laser output is started. First, the laser output A previously set on the first orbital track of the test writing area provided on the disk is set. The recording operation of the test signal is performed at (A). When such a test signal recording operation is performed, it is determined by the operation of the rotation detection circuit 16 whether or not the turntable 1, that is, the disk has made one rotation (step B).

If it is determined in step B that the disk has made one revolution, a test signal recording operation is performed on the second orbital track with a laser output B different from the laser output A (step C). When such a test signal recording operation is performed, it is determined by the operation of the rotation detection circuit 16 whether or not the disk has made one rotation (step D).

If it is determined at step D that the disk has made one revolution, at step A the level of the test signal recorded on the first orbital track and at step C the level detection of the test signal recorded on the second orbital track The operation is performed (Step E). The laser output C is set based on the signal level detected in Step E (Step F). By reproducing the recorded test signal and detecting its level, the relationship between each laser output and the recording characteristics of the disc can be detected, and the laser output C can be detected from the relationship between the laser output A and the laser output B. Can be set.

When the laser output C is set in step F, a test signal is recorded on the third orbiting track in the test writing area with the laser output C (step G). When the recording operation of the test signal is performed, the rotation detection circuit 16
Is used to determine whether the disk has made one revolution (step H). If it is determined in step H that the disk has made one revolution, the level of the test signal recorded on the third orbit track is detected in step G (step I).

When the level detection operation of the test signal is performed in step I, it is determined whether or not the detected level is an optimum level, that is, whether or not the level is in a level range suitable for recording a signal (step J). ). If it is determined in step J that the level is the optimum level, the operation of setting the laser output ends, and the laser output C set in step F is set as the laser output for performing the recording operation (step K). .

If it is determined in step J that the level is not the optimum level, the laser output is changed, and another operation such as a test signal recording operation is performed again (step L). In this embodiment, a test signal is recorded on the first orbital track with laser output A, then a test signal is recorded on the second orbital track with laser output B, and then the level of the test signal recorded on each orbital track is recorded. I tried to detect,
Immediately after the recording operation of the test signal on each orbit track, the level detection operation of the recorded signal can be performed.

The recording signal level detection operation performed after the recording operation of the test signal on each of the orbital tracks is performed by sampling a plurality of locations on the orbital tracks and calculating an average value of the detected level values. By doing so, an accurate level can be detected, and the laser output can be set accurately.

In this embodiment, when it is determined that the level of the signal recorded on the third track is not within the predetermined value, the laser output is changed and the test signal is again recorded. However, if it is determined that the level of the signal recorded on the third lap track is not within the predetermined value even after performing the recording operation of the test signal a predetermined number of times, the disc cannot perform the recording operation. May be determined and displayed on a display device or the like.

The laser output set when the test signal is recorded in the test writing area can be set in accordance with the type of the disc and the rotational speed of the disc on which the recording operation is performed.

In the present invention, one rotation of the disk is detected by using a signal obtained from a motor for rotating the turntable. However, means for detecting the rotation of the turntable is provided to detect the rotation. It can also be configured.

[0033]

According to the present invention, a test signal is recorded with different laser outputs on the first and second orbital tracks in the test writing area provided on the disk, and the first and second orbital tracks are recorded. Setting the laser output based on the level of the signal recorded on the third track, recording a test signal on the third track by the set laser output, and determining the level of the signal recorded on the third track. Since the laser output is set, that is, the test signal is recorded over the circumference of the track, the signal level accompanying the recording / reproducing operation of the test signal is obtained even if the rotation characteristics of the disc are uneven or eccentric. Can be accurately performed.

In the present invention, the level of the signal recorded on each track is detected by a sampling operation, so that the level of the signal recorded on the track can be averaged and detected, and the disk This has the effect that the signal level detection operation accompanying the recording / reproducing operation of the test signal can be performed more accurately even if the rotation characteristic has run-out or eccentricity.

In the present invention, one rotation of the disk is performed by using a signal obtained from a motor for driving the turntable, that is, a rotation detecting element and the like used for driving the motor for rotation. Can be used, so that the configuration is simplified.

According to the present invention, when the level of the signal recorded on the third track is not within a predetermined value, the laser output is changed and the test signal recording operation is performed again. It is possible to accurately set the laser output even for discs with variations. According to the present invention, when the test signal recording operation has been performed a predetermined number of times, it is determined that the disc cannot perform the recording operation, so that useless operation can be prevented.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a laser output setting method according to the present invention.

FIG. 2 is a block circuit diagram showing one embodiment of an optical disk recording / reproducing apparatus according to the laser output setting method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Turntable 2 Electric motor 3 Disk 4 Optical pickup 5 RF signal amplification circuit 6 Pickup control circuit 7 Digital signal processing circuit 10 System control circuit 12 Laser drive circuit 13 Laser output setting circuit 15 Signal level detection circuit 16 Rotation detection circuit

Claims (5)

[Claims] 1. A test signal is recorded on a first orbital track and a second orbital track in a test writing area provided on a disc with different laser outputs, and is recorded on the first and second orbital tracks. The laser output is set based on the signal level, a test signal is recorded on the third track by the set laser output, and the laser output is determined by determining the level of the signal recorded on the third track. A method for setting a laser output of an optical disc recording / reproducing apparatus, wherein the setting is performed. 2. The laser output setting method according to claim 1, wherein the level of a signal recorded on each orbital track is detected by a sampling operation. 3. The laser output setting method according to claim 1, wherein one rotation of the disk is detected by a signal obtained from a motor for rotating the turntable. 4. The method according to claim 1, wherein when the level of the signal recorded on the third orbit track is not within a predetermined value, the operation of recording the test signal is performed again after changing the laser output. The laser power setting method described. 5. The laser output setting method according to claim 4, wherein when the recording operation of the test signal is performed a predetermined number of times, it is determined that the disk cannot perform the recording operation.