JPH117634A - Optical disk drive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical disk device that enables high speed recovering in the case of access outside the data area of an optical disk or in the occurrence of abnormality in focus servo at a position on a damaged disk. SOLUTION: This device is equipped with a disk 1 on which information is recorded, an optical pickup 2 for optically reading the information so recorded, a traverse driving means 4 for moving the optical pickup 2 in the disk radial direction, a means 5 for detecting the maximum amplitude of a focus error signal in the direction vertical to the data recording face, and a means 7 for inner circumferential moving and recovering at the time of a focus error above a specific level such that the focus servo can be pulled in by moving the optical pickup 2 for a specific quantity in the inner circumferential direction if the maximum amplitude above a specific level is detected at the time of setting error of the focus servo. In this case, if the focus servo is abnormal, the optical pickup 2 is moved in the inner circumferential direction, enabling the focus servo to recover at high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a recovery process when a focus servo error occurs during access to an optical disk device.

[0002]

2. Description of the Related Art Conventionally, as a process for recovering from a focus servo abnormality occurring during access to an optical disk device, for example, a process disclosed in Japanese Patent Application Laid-Open No. 8-194953 is known. FIG. 6 is a block diagram schematically showing the configuration of such a conventional optical disk device. Hereinafter, FIG.
The configuration of the above-described conventional optical disk device will be described with reference to FIG.

In FIG. 6, 1 is a disk on which information is recorded, 2 is an optical pickup for optically reading information recorded on the disk 1, and 4 is a traverse driving means for moving the optical pickup 2 in the disk radial direction. Reference numeral 5 denotes a focus error amplitude maximum value detecting means for detecting a maximum amplitude value of a focus error signal, which is a vertical position error signal from the data recording surface, and reference numeral 6 denotes a tracking servo slippage prevention means for preventing tracking servo slippage. .

Next, the operation of the above-mentioned conventional optical disk device will be described with reference to FIG. First, spindle motor 3
When the disc 1 is rotating, the optical pickup 2 is moved to a desired position in the radial direction of the disc 1 by the traverse driving means 4, and the tracking is controlled to perform the access. While the optical pickup 2 is being accessed, the focus error amplitude maximum value detecting means 5 detects the maximum value of the focus error amplitude, and based on the detected value, the tracking servo deviating means 6 prevents the tracking servo of the optical pickup 2 from deviating. Control is performed.

[0005]

However, in the above-mentioned conventional optical disk device, it is possible to avoid an abnormal tracking servo when accessing the vicinity of a boundary between different groove structures, such as a data area using pits and a data area using grooves. When the optical pickup moves to the highly reflective surface outside the data area near the outermost circumference of the disk and fails to pull in the focus servo, that is, when the runaway to the outer circumference of the traverse is performed or the access accuracy is poor due to the tracking servo abnormality, At the time of access when the pickup comes out of the data area of the disk, or when an abnormality of the focus servo occurs at a position on the disk having a flaw, there is a problem that the focus servo cannot be pulled in.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and can be performed at a high speed even when an access is made outside the data area of an optical disk or when a focus servo error occurs at a position on a damaged disk. It is an object of the present invention to provide an optical disk device that enables focus servo pull-in.

[0007]

An optical disk apparatus according to the present invention detects a maximum value of a focus error amplitude when a focus servo pull-in fails, and uses the value to detect a position where an optical pickup is outside a data area of a disk or a scratch on a disk. The optical pickup is moved in the inner circumferential direction by a fixed amount by the traverse driving means, and then the focus servo is pulled in again.

According to the present invention, the focus servo is pulled again after the optical pickup is moved to a normal data area, so that the focus servo can be performed at the time of access to the vicinity of the outermost circumference of the disk outside the data area or on the scratch of the disk. Even if an abnormality occurs, it is possible to obtain an optical disk device that can perform focus servo pull-in at high speed.

[0009]

DETAILED DESCRIPTION OF THE INVENTION An optical disk device according to the first aspect of the present invention includes a disk on which information is recorded, an optical pickup for optically reading information recorded on the disk, and a disk having the optical pickup. Traverse driving means moving in the radial direction, focus error amplitude maximum value detecting means detecting the amplitude maximum value of the focus error signal in the direction perpendicular to the data recording surface, and amplitude maximum value when the focus servo pull-in failure of a certain value or more fails. When the optical pickup is detected, the optical pickup is moved in the inner circumferential direction by a fixed amount to move the focus servo. Even when the optical pickup moves to the data area, return it to the data area and It has the effect that the write can be returned to the high speed.

In the optical disc apparatus according to the present invention, when the focus error is equal to or more than a predetermined value, the inner peripheral movement return means detects a maximum amplitude value when a focus servo pull-in of a certain value or less fails. The optical pickup is moved in the inner circumferential direction by a fixed amount to pull in the focus servo. When the focus error is below a certain level, the inner circumferential movement is returned. Even when the optical pickup is moved, the optical pickup can be returned to the data area and the focus servo can be returned at high speed.

In the optical disc apparatus according to a third aspect of the present invention, the focus error amplitude maximum value detection means is an RF signal maximum value detection means for detecting a maximum value of an RF signal indicating the amount of reflected light from the disk. When the focus error is equal to or greater than a predetermined value, the inner peripheral movement returning means detects the RF signal maximum value equal to or greater than a certain value during access. When the pickup is moved in the inner circumferential direction by a fixed amount and then the tracking servo is pulled in, the inner circumferential movement return means is used when the RF is higher than a certain value. During access, the optical pickup moves to the vicinity of the outermost circumference of the disk outside the data area. And the tracking servo can be returned at high speed even at that time. That.

According to a fourth aspect of the present invention, there is provided an optical disk apparatus, wherein: a disk on which information is recorded; an optical pickup for optically reading information recorded on the disk; and the optical pickup is moved in a radial direction of the disk. When a focus servo error occurs during access, the optical pickup is moved by a fixed amount in the inner circumferential direction to perform focus servo retraction, and when the focus servo retraction fails, the optical pickup is moved by a fixed amount in the outer circumferential direction. Traverse alternate drive return means for pulling in the focus servo by means of a focus servo abnormality. A disk with two or more scratches cannot be pulled in even if it moves a certain amount in the inner circumferential direction because it has scratches. Even in this case, move the focus servo to another location It has the effect that the trough that can burn them.

According to a fifth aspect of the present invention, there is provided an optical disk apparatus comprising: a disk on which information is recorded; an optical pickup for optically reading information recorded on the disk; and an optical pickup which is moved in a radial direction of the disk. Traverse drive means that moves the optical pickup by a fixed amount in the same direction as the traverse drive direction immediately before the occurrence of the focus servo abnormality when the focus servo abnormality occurs at the time of access; And a drive return unit, which has the effect of allowing access to be resumed by passing through the position on the disk where the focus servo error has occurred during access.

Hereinafter, based on the attached drawings and FIGS. 1 to 5,
An embodiment of the present invention will be described in detail. (First Embodiment) First, a configuration of an optical disk device according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing the configuration of the optical disk device according to the first embodiment of the present invention.

In FIG. 1, 1 is a disk on which information is recorded, 2 is an optical pickup for optically reading information recorded on the disk 1, 3 is a spindle motor that rotates the disk 1, and 4 is an optical motor. Pickup 2
A traverse drive means for moving the focus error signal in the radial direction of the disk 1, a focus error amplitude maximum value detection means for detecting the amplitude maximum value of a focus error signal which is a vertical position error signal from the data recording surface, and a focus servo 7 When the focus error amplitude maximum value at the time of pull-in failure is detected to be equal to or more than a predetermined value, the optical pickup is moved in the inner circumferential direction by a predetermined amount to pull in the focus servo.

Next, with reference to FIG. 1, the operation of the optical disk device according to the present embodiment configured as described above will be described. First, while the disk 1 is being rotated by the spindle motor 3, the optical pickup 2 is moved to a desired position in the radial direction of the disk 1 by the traverse driving means 4, and access is performed by tracking servo and focus servo. Then, for example, the optical pickup 2 moves to the vicinity of the outermost periphery of the disk 1 being rotated by the spindle motor 3.
When the focus servo failure occurs due to the occurrence of a focus servo abnormality when the access is made by the focus error, the focus error amplitude maximum value detection means 5 detects the amplitude of the focus error.

When the detected amplitude value is equal to or more than a predetermined value, the position of the optical pickup 2 is set to be smaller than the data area near the outermost circumference of the disk, which is outside the data area, by the inner circumference movement returning means 7 when the focus error is equal to or more than a certain value. It is determined that the area is in a high reflectance area. Then, the traverse driving unit 4 attempts to pull in the focus servo again at the position where the optical pickup 2 is moved in the inner circumferential direction by a fixed distance set as the distance from the position to the data area.
In this way, when the optical pickup 2 accesses the data area near the outermost periphery of the disk, which is higher in reflectance than the data area outside the data area, the optical pickup 2 is returned to the data area and the focus servo is performed. Enables recovery from abnormal conditions.

(Second Embodiment) Hereinafter, a configuration of an optical disk device according to a second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the optical disk device according to the second embodiment of the present invention. In FIG. 2, 1 is a disk on which information is recorded, 2 is an optical pickup for optically reading information recorded on the disk 1, and 3 is a spindle motor as a motor for rotating the disk 1.

Reference numeral 4 denotes an optical pickup 2 for a disc 1
5 is a traverse driving means which moves in the radial direction, 5 is a focus error amplitude maximum value detecting means which detects a maximum amplitude of a focus error signal which is a vertical position error signal from the data recording surface, and 8 is when a focus servo pull-in fails. When the maximum value of the amplitude is detected to be equal to or smaller than a predetermined value, the optical pickup is moved in the inner circumferential direction by a fixed amount, and the focus servo is pulled in.

Next, with reference to FIG. 2, the operation of the optical disk device according to the present embodiment configured as described above will be described. First, while the disk 1 is being rotated by the spindle motor 3, the optical pickup 2 is moved to a desired position in the radial direction of the disk 1 by the traverse driving means 4, and access is performed by tracking servo and focus servo. Then, for example, the optical pickup 2 moves to the vicinity of the outermost periphery of the disk 1 being rotated by the spindle motor 3.
When the focus servo failure occurs due to the occurrence of a focus servo abnormality when the access is made by the focus error, the focus error amplitude maximum value detection means 5 detects the amplitude of the focus error.

When the detected amplitude value is equal to or less than a fixed value, the position of the optical pickup 2 is set to be smaller than the data area near the outermost circumference of the disk, which is outside the data area, by the inner-circumferential movement returning means 8 when the focus error is equal to or less than a fixed value. It is determined that the area is in a low reflectance area. Then, the traverse driving unit 4 attempts to pull in the focus servo again at the position where the optical pickup 2 is moved in the inner circumferential direction by a fixed distance set as the distance from the position to the data area.
In this way, the optical pickup moves to an area outside the disk where there is no reflected light from the disk, or the optical pickup 2 accesses too far to an area outside the data area and lower in reflectance than the data area near the outermost periphery of the disk. Even in such a case, the optical pickup 2 is returned to the data area to enable recovery from the abnormal state of the focus servo.

(Third Embodiment) The configuration of an optical disk device according to a third embodiment of the present invention will be described below with reference to FIG. FIG. 3 is a block diagram showing a configuration of an optical disk device according to the third embodiment of the present invention. In FIG. 3, 1 is a disk on which information is recorded, 2 is an optical pickup for optically reading information recorded on the disk 1, and 3 is a spindle motor which is a motor for rotating the disk 1.

Reference numeral 4 denotes an optical pickup 2 and a disk 1
A traverse driving means 9 which moves in the radial direction of the RF signal;
0 indicates that, when it is detected that the maximum value of the RF signal is equal to or more than a certain value during access, the tracking servo which is a lens drive in the disk radial direction is made inoperative and the optical pickup is moved by a certain amount in the inner circumferential direction. Is a means for returning the inner circumference movement when the RF is more than a predetermined value for pulling in the tracking servo.

Next, with reference to FIG. 3, the operation of the optical disk device according to the present embodiment configured as described above will be described. First, while the disk 1 is being rotated by the spindle motor 3, the optical pickup 2 is moved to a desired position in the radial direction of the disk 1 by the traverse driving means 4, and access is performed by tracking servo and focus servo. Then, for example, the optical pickup 2 moves to the vicinity of the outermost periphery of the disk 1 being rotated by the spindle motor 3.
When accessed by R
In the region where the reflectance of the F signal is high, the maximum value of the RF signal is detected by the RF signal maximum value detecting means 9.

When the detected maximum value of the RF signal is equal to or more than a certain value, the position of the optical pickup 2 is determined by the inner circumference movement return means 10 when the RF is equal to or more than the data area near the outermost circumference of the disk. Is determined to be in a region where the RF signal reflectance is high. Then, after the tracking servo is disabled, the traverse driving means 4 moves the optical pickup 2 in the inner circumferential direction by a certain distance set as the distance from the position to the data area, and then returns to the tracking servo. Try to pull in. In this way, even when the optical pickup 2 is accessing too far from the data area near the outermost periphery of the disk, which is outside the data area, to an area having a higher RF signal reflectivity, the optical pickup 2 is moved into the data area. Then, the tracking servo can be returned to normal.

(Fourth Embodiment) The configuration of an optical disk device according to a fourth embodiment of the present invention will be described below with reference to FIG. FIG. 4 is a block diagram showing a configuration of an optical disk device according to the fourth embodiment of the present invention. In FIG. 4, reference numeral 1 denotes a disk on which information is recorded, 2 denotes an optical pickup for optically reading information recorded on the disk 1, and 3 denotes a spindle motor which is a motor for rotating the disk 1.

Reference numeral 4 denotes an optical pickup 2 for a disc 1
The traverse driving means 11 which moves in the radial direction of the optical disc 2 is used when the optical pickup 2 attempts to access a desired position in the radial direction of the disc 1 and a focus servo error occurs due to a scratch on the disc 1 or the like. The optical pickup 2 is moved, for example, by a fixed amount in the inner circumferential direction to perform focus servo pull-in. If the focus servo pull-in still fails, the optical pickup 2 is further moved in the opposite outer circumferential direction by a fixed amount and then refocused. This is traverse alternate drive return means for focus servo abnormality when the servo is pulled in.

Next, with reference to FIG. 4, the operation of the optical disk device according to the present embodiment configured as described above will be described. First, while the disk 1 is being rotated by the spindle motor 3, the optical pickup 2 is moved to a desired position in the radial direction of the disk 1 by the traverse driving means 4, and access is performed by tracking servo and focus servo.

If, for example, the optical pickup 2 makes an access by passing through a scratch on the disk 1 being rotated by the spindle motor 3, a focus servo error occurs and the focus servo pull-in fails, The optical pickup 2 is moved, for example, in the inner circumferential direction by a predetermined amount in the inner circumferential direction and the outer circumferential direction by the traverse alternate drive return unit 11 when the focus servo is abnormal, and the focus servo is pulled in again.
If the focus servo pull-in still fails, the optical pickup 2 is further moved in the opposite outer circumferential direction by a fixed amount, and then the focus servo pull-in is attempted again. In this way, when the optical pickup 2 first moves, for example, in the inner circumferential direction, even if there are two scratches on the disk 1 having the same distance as a predetermined fixed moving distance, the optical pickup 2 moves in the opposite direction again. It can be moved to pull in the focus servo.

(Fifth Embodiment) The configuration of an optical disk device according to a fifth embodiment of the present invention will be described below with reference to FIG. FIG. 5 is a block diagram showing a configuration of an optical disk device according to the fifth embodiment of the present invention. In FIG. 5, reference numeral 1 denotes a disk on which information is recorded, 2 denotes an optical pickup for optically reading information recorded on the disk 1, and 3 denotes a spindle motor as a motor for rotating the disk 1.

Reference numeral 4 denotes an optical pickup 2 for a disc 1
The traverse driving means 12 which moves in the radial direction of the optical pickup 2 attempts to access a desired position in the radial direction of the disk 1 by the optical pickup 2 and when a focus servo abnormality occurs due to a scratch on the disk 1 or the like, This is a same-direction traverse drive return unit in the case of a focus servo abnormality, which is moved in a predetermined amount in the same direction as the traverse drive direction immediately before the occurrence of the focus servo abnormality, and then performs focus servo pull-in again.

Next, with reference to FIG. 5, the operation of the optical disk device according to the present embodiment configured as described above will be described. First, while the disk 1 is being rotated by the spindle motor 3, the optical pickup 2 is moved to a desired position in the radial direction of the disk 1 by the traverse driving means 4, and access is performed by tracking servo and focus servo.

Then, for example, as a result of the optical pickup 2 making an access by passing through a scratch on the disk 1 being rotated by the spindle motor 3, a focus servo abnormality occurs on the scratch and the focus servo is pulled in. In the case of failure, the same-direction traverse drive return means 12 at the time of focus servo abnormality moves the optical pickup 2 by a predetermined amount in the same direction as the traverse drive direction immediately before the occurrence of the focus servo abnormality, and attempts to pull in the focus servo. . In this way, even if there is a scratch on the disc 1, access can be resumed through the scratch.

[0034]

The optical disk apparatus according to the present invention is constructed as described above. In particular, when it is detected that the maximum value of the focus error amplitude when the focus servo pull-in fails is not less than a certain value, the optical pickup is internally mounted. By providing the inner circumference movement return means when the focus error is more than a certain value when the focus servo is pulled by moving a certain amount in the circumferential direction, it is located near the outermost circumference of the disk when runaway to the outer circumference of the traverse due to tracking servo error or in a system with poor access accuracy When the optical pickup moves to the high-reflection surface outside the data area and the focus servo pull-in fails, the optical pickup can be quickly moved in the inner circumferential direction to quickly read information.

Further, the optical disk device according to the present invention comprises:
With the configuration as described above, in particular, when it is detected that the maximum value of the focus error amplitude when the focus servo pull-in fails is less than a certain value, the optical pickup is moved by a certain amount in the inner circumferential direction to pull in the focus servo. By providing the inner circumference movement return means when the focus error is below a certain level, the optical pickup moves to an area outside the disk where there is no reflected light from the disk at the time of runaway to the outer circumference of the traverse due to tracking servo abnormality or in a system with poor access accuracy. When the focus servo pull-in fails, the optical pickup can be quickly moved in the inner circumferential direction to quickly read information.

Further, the optical disk device according to the present invention comprises:
With the configuration as described above, in particular, when it is detected that the maximum value of the RF signal is greater than or equal to a certain value during access, the tracking servo, which is a lens drive in the disk radial direction, is made inoperative and the optical pickup is internally driven. By providing the inner circumference movement return means when the RF is more than a certain value for drawing the tracking servo after moving a certain amount in the circumferential direction, if the maximum value of the RF signal is detected to be more than the certain value during access, the optical pickup Judging that it has moved to an area with higher reflectivity than the data area near the outermost circumference of the disk,
Since the tracking servo is drawn by moving in the inner circumferential direction while the focus servo is operated, reading of information can be restored at high speed.

Further, the optical disk device according to the present invention comprises:
With the configuration as described above, in particular, when a focus servo error occurs at the time of access, the optical pickup is moved by a certain amount in the inner circumferential direction to perform the focus servo pull-in. In the case where two scratches having the same interval as the preset moving distance of the optical pickup are present on the disk by providing the focus servo abnormal traverse alternate drive return means which is moved by a predetermined amount to move the focus servo. However, the information can be read by trying the pull-in of the focus servo again.

Further, the optical disk device according to the present invention comprises:
With the configuration as described above, particularly when a focus servo error occurs during access, a focus servo error in which the optical pickup is moved by a fixed amount in the same direction as the traverse drive direction immediately before the focus servo error occurs to pull in the focus servo. When the same direction traverse drive return means is provided, even if there is a flaw on the disk, access can be resumed through the flaw, so that the number of retries of access to the target sector can be reduced, It is possible to increase the access speed to the sector near the upper flaw.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an optical disc device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an optical disk device according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of an optical disc device according to a third embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of an optical disk device according to a fourth embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of an optical disk device according to a fifth embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a conventional optical disk device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Disc 2 Optical pickup 3 Spindle motor 4 Traverse drive means 5 Focus error amplitude maximum value detection means 6 Tracking servo departure prevention means 7 Inner circumference movement return means when focus error is more than fixed 8 Inner circumference movement return means when focus error is less than fixed 9 RF Signal maximum value detection means 10 Inner circumference movement return means when RF is constant or more 11 Traverse alternate drive return means when focus servo is abnormal 12 Same direction traverse drive return means when focus servo servo is abnormal

Claims (5)

[Claims] 1. A disc on which information is recorded, an optical pickup for optically reading information recorded on the disc, traverse driving means for moving the optical pickup in a radial direction of the disc, Focus error amplitude maximum value detecting means for detecting the amplitude maximum value of the focus error signal, which is a position error signal, and when detecting the amplitude maximum value when the focus servo pull-in fails to be a fixed value or more, the optical pickup is moved in the inner circumferential direction. An optical disc apparatus comprising: an inner-peripheral-movement returning unit that moves a fixed amount to pull in a focus servo when a focus error exceeds a certain level. 2. The optical pickup according to claim 1, wherein the optical pickup is moved in the inner circumferential direction by a fixed amount when the focus error is equal to or more than a fixed value, and the inner peripheral movement returning means detects the maximum amplitude value when the focus servo pull-in operation is smaller than the fixed value. 2. The optical disk device according to claim 1, wherein the inner peripheral movement return means is used when the focus error is below a certain level, the focus servo being pulled in. 3. The focus error amplitude maximum value detecting means is an RF signal maximum value detecting means for detecting a maximum value of an RF signal indicating the amount of reflected light from a disk, and the inner peripheral movement returning means when the focus error is equal to or more than a predetermined value. If an RF signal maximum value equal to or more than a certain value is detected during access, the tracking servo for driving the optical pickup in the disk radial direction is made inoperative, and the optical pickup is moved in the inner circumferential direction by a certain amount, and then the tracking is performed. RF pull in servo
2. An optical disk device according to claim 1, wherein said inner peripheral movement returning means is used when the distance exceeds a predetermined value. 4. A disc on which information is recorded, an optical pickup for optically reading the information recorded on the disc, a traverse driving means for moving the optical pickup in a radial direction of the disc, and a focus servo error occurs at the time of access. In this case, the optical pickup is moved in a fixed amount in the inner circumferential direction to perform focus servo retraction, and if the focus servo retraction fails, the optical servo is moved in a fixed amount in the outer circumferential direction to retract the focus servo. An optical disk device characterized by comprising: 5. A disc on which information is recorded, an optical pickup for optically reading the information recorded on the disc, a traverse drive means for moving the optical pickup in a radial direction of the disc, and a focus servo error occurs at the time of access. An optical disc, comprising: a focus servo abnormality in-direction traverse drive return means for moving the optical pickup by a fixed amount in the same direction as the traverse drive direction immediately before the occurrence of the focus servo abnormality and pulling in the focus servo. apparatus.