JP2001134941A - Recording control method of optical disk recoridng/ reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the recording control method used for an optical disk recording/reproducing device capable of recording a signal on the disk by laser beam ejected from an optical pickup. SOLUTION: In the optical disk recording/reproducing device constituted so as to record the signal on the disk after the output of the laser beam ejected from a laser element is adjusted by means of performing the recording operation of a test signal on the trial writing area which is arranged on the disk 1, the arrangement is made so as to adjust the rise property of the laser beam at the time of adjusting the output of the laser beam.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc recording apparatus which records a signal on a disc by a laser beam emitted from an optical pickup and reproduces a signal recorded on the disc by the laser beam. It relates to a playback device.

[0002]

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

In such an optical disk recording / reproducing apparatus, pits are formed on a disk by a laser beam. However, if the output of the laser beam is not optimal, the pit shape is too large or small. Too much. 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 the laser power for recording by
Such a technique is disclosed in, for example, JP-A-6-76288.

[0004]

The operation of recording a signal on a disk is performed by forming a pit on a signal track provided on the disk by a laser beam output from a laser element. Is set to be a specified size. The recording operation of such a signal is performed by rotating the disk at a predetermined constant linear velocity, but recently, the recording operation is performed with the linear velocity during the recording operation being several times the predetermined velocity. An optical disk recording / reproducing device capable of performing such operations has been commercialized.

[0005] The write-once optical disk recording / reproducing apparatus has a characteristic that a signal recording operation can be performed only once at the same location of a recording area provided on the disk. Therefore, in such an optical disc recording / reproducing apparatus, when performing a signal recording operation, it is configured to recognize the position where the signal is recorded up to the previous time and start the signal recording operation from the position after the position. ing. A link between the previous recording end position and the signal recording start position is called a link, and it is required to narrow the link portion.

However, due to the delay of the rising characteristics of the laser element incorporated in the optical pickup, no signal is recorded in the link portion, that is, an unrecorded portion is formed. In this case, there is a problem that when performing the signal reproducing operation, the signal reproducing characteristics are adversely affected. In order to solve such a problem, a method of overlapping a previous recording end position and a signal recording start position is adopted.

FIG. 3 is an explanatory diagram showing a signal recording position relationship of a disc when a signal recording operation is performed by a method of overlapping a previous recording end position and a signal recording start position, wherein T1 to T2 are shown. The portion recorded by the previous recording operation is shown, and T3 indicates the recording start position of the next signal. As is apparent from FIG.
Up to 2 is a link portion, and a signal is recorded twice.

In this case, since the link portion is double-recorded, there is no unrecorded portion, and the adverse effect on the reproduction characteristics is reduced. Become. Therefore, there is a problem that the synchronization of the PLL is disrupted when performing the signal reproducing operation.

An object of the present invention is to provide a recording control method for an optical disk recording / reproducing apparatus which solves such a problem.

[0010]

According to the present invention, a signal is recorded on a disk after adjusting the output of laser light emitted from a laser element by performing a test signal recording operation on a test writing area provided on the disk. In the optical disk recording / reproducing apparatus, the rising characteristic of the laser light is adjusted when the output of the laser light is adjusted.

[0011]

FIG. 1 is a block circuit diagram showing an embodiment of an optical disk recording / reproducing apparatus according to the present invention, and FIG. 2 is an explanatory diagram showing a signal recording positional relationship for explaining the operation of the present invention. In FIG. 1, reference numeral 1 denotes a disk which is mounted on a turntable (not shown) which is driven to rotate by a spindle motor (not shown) and which is driven to rotate by the rotation of the turntable. The recording is performed by a groove called a groove, and a signal recording / reproducing operation is performed based on a wobble signal obtained from the groove. Reference numeral 2 denotes a laser element for irradiating the disk 1 with laser light, and a monitoring diode for monitoring the laser light emitted from the laser element is incorporated, and a photodetector for receiving the laser reflected from the signal surface of the disk 1 An optical pickup incorporated therein, which is configured to be displaced in the radial direction of the disk 1.

Reference numeral 3 denotes an RF signal amplifying circuit that amplifies an RF signal obtained from a photodetector incorporated in the optical pickup 2 and shapes the waveform, and 4 denotes a signal obtained through the RF signal amplifying circuit 4. Laser light emitted from the optical pickup 2 based on the
And a pickup control circuit that performs a focusing control operation for focusing on the signal surface of the optical disk and a tracking control operation for causing the laser light to follow a signal track on the signal surface.

Reference numeral 5 denotes a digital signal processing circuit that performs digital signal processing of signals output from the RF signal amplifier circuit 3 and performs demodulation operations of various signals, and 6 denotes a digital signal processed by the digital signal processing circuit 5. A signal reproducing circuit to which a signal is input. When the information recorded on the disc 1 is an audio signal, the signal is converted into an analog signal and then output to an amplifier or the like, and when the data signal is data such as computer software. Has the function of outputting the digital signal to the computer device 7 as it is.

A system control circuit 8 receives a signal demodulated by the digital signal processing circuit 5 and performs various control operations in response to an operation switching control signal output from the computer device 7. Disc 1
A memory circuit in which a program for recording a test signal is stored in a test writing area provided in the memory is provided.

Reference numeral 9 denotes a laser drive circuit for supplying a drive signal to a laser element incorporated in the optical pickup 2, and 10 denotes a laser output control circuit whose operation is controlled by the system control circuit 8. The laser output is set by controlling the circuit 9. A signal recording circuit 11 receives a recording signal such as a test signal or an information signal and controls a laser light irradiation operation by the laser driving circuit 9 in accordance with the signal to record the signal on the disk 1. It is.

Reference numeral 12 denotes a laser servo circuit for controlling a drive signal supplied from the laser drive circuit 9 to the laser element. The laser servo circuit 12 controls the laser based on a signal obtained from a monitor diode incorporated in the optical pickup 2. It is configured to perform a control operation of a drive signal supplied to the device and to control a laser device by a control signal output from the system control circuit 8.

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. When a reproduction switching signal output from the computer device 7 is input to the system control circuit 8, a control operation for a reproduction operation by the system control circuit 8 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 from the laser driving circuit 9 to the laser element incorporated in the optical pickup 2. Is set to

When the control operation for such a reproducing operation is started, a rotation control operation of the spindle motor is performed by a spindle motor driving circuit (not shown), and a focusing control operation and a tracking control operation of the optical pickup 2 are performed. Is started, and the reading operation of the signal from the disk 1 by the optical pickup 2 is started. The signal read by the optical pickup 2 is input to the digital signal processing circuit 5 through the RF signal amplification circuit 3, and the signal is demodulated. When signal processing is performed by the digital signal processing circuit 5 to extract information data, the information data is applied to a signal reproduction circuit 6 after signal processing such as error correction is performed.

When the information data read from the disk 1 is an audio signal, the signal reproducing circuit 6 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 to the computer 7 as it is.

In such a circuit configuration, when the disk 1 is inserted into the mounting portion of the disk in order to perform a signal recording operation, a laser output setting operation is performed. Such an operation of setting the laser output is performed based on a program stored in a memory circuit provided in the system control circuit 8. The operation of setting the laser output is performed in a stepwise manner by the control signal output from the laser output control circuit 10 to control the magnitude of the drive current supplied from the laser drive circuit 9 to the laser device incorporated in the optical pickup 2. This is performed by recording the test signal while changing it to the above and reproducing the recorded signal.

When the magnitude of the driving current supplied to the laser element is changed stepwise, the output of the laser light output from the laser element changes, so that the level of the signal recorded on the disk 1 also changes. Become. Then, the level of the signal recorded on the disc 1 with respect to the laser output is detected, and when the level of the signal to be reproduced reaches a desired value, the laser output at that time is set as the laser output for performing the recording operation.

The operation of recording the data signal in the signal recording area is started by the laser output set in this manner. When the recording operation of the data signal is being performed, the laser reflected from the disk 1 By monitoring the change in light, the value of the drive current supplied from the laser drive circuit 9 to the laser element is changed so that the laser output is always adjusted to the optimum laser output for the recording operation.

As described above, the recording operation of the test signal in the test writing area and the recording operation of the data signal in the signal recording area are performed. In order to perform the recording operation, the laser driving circuit 9 supplies the laser element. The control operation by the laser servo circuit 12 is always performed with respect to the drive signal supplied to.

As described above, the setting operation of the laser output is performed by the operation of recording and reproducing the test signal in the test writing area. Next, the recording control method which is the gist of the present invention will be described.

The laser output set by the above-described operation has a fixed rising characteristic, and does not take into account that the characteristics of the laser element change with temperature or aging. As a result, the signal recording operation is performed as shown in FIG. 3, but since the length of the link portion changes according to the change in the rising characteristic of the laser beam, the double-recorded link portion has to be lengthened. Did not get.

According to the present invention, the recording operation of the test signal in the test writing area is performed while changing the rising characteristic of the laser element, and the gap between the test signals is detected when the recording operation of the test signal is performed. Then, the gap is adjusted so that the rising characteristic becomes the narrowest. Such a rise characteristic can be changed by changing the gain of the laser servo circuit 12 or by applying an offset signal to the servo signal.

In this way, the operation of adjusting the rising characteristic of the laser element is performed. By performing the setting operation of the timing for starting the signal recording operation based on the rising characteristic thus set, the link operation is performed. The signal recording operation can be performed in a state where the length of the portion is minimized. FIG. 2 shows a positional relationship of a recording signal when recording is performed in a state where such adjustment is performed, and a region where a data signal is recorded by a previous recording operation is from T1 to T2. . The position at which the signal recording operation is started following the disk 1 recorded in this way is T3, and it is possible to make T2 and T3 substantially coincide.
That is, since the double recorded portion and the unrecorded portion can be reduced as much as possible, not only can the recording area of the disk 1 be used effectively, but also the recording operation can be performed without any trouble in the reproducing operation. Can be done.

Further, if the adjustment operation for changing the rising characteristic of the laser beam is performed by changing the characteristic from a gradual characteristic to a steep characteristic direction, the driving current flowing through the laser element can be suppressed, thereby damaging the laser element. Danger can be reduced.

[0029]

According to the present invention, a signal is recorded on a disk after the output of a laser beam emitted from a laser element is adjusted by performing a test signal recording operation on a test writing area provided on the disk. In the configured optical disc recording / reproducing device, the rising characteristics of the laser light are adjusted when adjusting the output of the laser light.
Even if the characteristics of the laser element change, the signal recording operation can always be performed in a good state.

Further, according to the present invention, a laser servo circuit for controlling the operation of a laser drive circuit for supplying a drive current to a laser element is provided, and a rise characteristic is obtained by changing the gain of the servo circuit or applying an offset signal to the servo signal. Since the adjustment is performed, there is an advantage that the circuit configuration can be simplified.

According to the present invention, the rising characteristic of the laser beam is adjusted by changing the rising characteristic of the laser beam from a gradual characteristic to a steep characteristic direction, so that the drive current flowing through the laser element can be suppressed. As a result, there is an effect that the risk of damaging the laser element can be reduced.

Further, according to the present invention, since the recording start timing is set in accordance with the rising characteristic of the laser beam, the time between the area recorded by the previous recording operation and the area recorded next is set. Since the double-recorded portion and the unrecorded portion of a connection portion can be reduced as much as possible, not only can the recording area of the disc be used effectively, but also the recording operation can be performed without any trouble in the reproducing operation. It has the advantage that it can be done.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram showing one embodiment of an optical disk recording / reproducing apparatus according to a recording control method of the present invention.

FIG. 2 is an explanatory diagram showing a signal recording positional relationship for explaining an operation of the present invention.

FIG. 3 is an explanatory diagram showing a signal recording positional relationship for explaining a conventional recording operation.

[Description of Signs] 1 disc 2 optical pickup 3 RF signal amplification circuit 4 pickup control circuit 5 digital signal processing circuit 7 computer device 8 system control circuit 9 laser drive circuit 10 laser output control circuit 12 laser servo circuit

Claims (5)

[Claims] An optical disk configured to record a signal on a disk after adjusting an output of a laser beam irradiated from a laser element by performing a test signal recording operation on a test writing area provided on the disk. A recording control method for an optical disk recording / reproducing apparatus, wherein a rise characteristic of a laser light at the time of adjusting a laser light output is adjusted in the recording / reproducing apparatus. 2. A laser servo circuit for controlling an operation of a laser drive circuit for supplying a drive current to a laser element, wherein a rise characteristic is adjusted by changing a gain of the servo circuit. Item 1
3. The recording control method according to item 1. 3. A laser servo circuit for controlling an operation of a laser drive circuit for supplying a drive current to a laser element, and a rising characteristic is adjusted by applying an offset signal to a servo signal of the servo circuit. 2. The recording control method according to claim 1, wherein: 4. The recording control method according to claim 1, wherein the rising characteristic of the laser beam is adjusted by changing the rising characteristic from a gentle characteristic to a steep characteristic direction. 5. The recording control method according to claim 1, wherein the recording start timing is set in accordance with the rising characteristics of the laser light.