JP2002083432A - Disk drive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfactorily set the track position to which the track jump is carried out at the time of track jump even for a disk drive allowing the high speed reproducing or high speed recording operation. SOLUTION: At the time of controlling the position of the laser beam emitted with an optical pickup 12 on the disk 1 by a control means 20, when the emitting position of the laser beam is track-jumped to the prescribed objective track position, the jump is made at the position scanned precedently by the specified distance from the objective track position, and the specified distance to be precedently jumped is arranged so as to variably set in accordance with the rotating speed of the disk set by a spindle servo means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk drive for recording or reproducing data on, for example, an optical disk or a magneto-optical disk, and more particularly to a track jump for scanning a track formed on the disk. When it comes to technology.

[0002]

2. Description of the Related Art Conventionally, CD (Compact Disc), MD (Mi
ni Disc), DVD (Digital VideoDisc or Digital V)
2. Description of the Related Art In a disk drive device that records or reproduces data on an optical disk such as an erasatile disk) or a magneto-optical disk, an optical pickup that irradiates the disk with a laser beam needs to perform tracking control to follow a track on the disk.

That is, an optical pickup for irradiating a laser beam to a disk requires a sled feed for moving the entire pickup in the radial direction of the disk and only a few optical components for irradiating a laser beam such as a lens in the optical pickup.
The target track position on the disk is set by tracking control by a tracking adjustment mechanism that moves the disk in the radial direction within a range of approximately mm (for example, a range of approximately several hundred tracks in the number of tracks). Here, for example, when performing recording or reproduction continuously on a spirally formed track on a disk, a combination of movement of the entire optical pickup by thread feed and tracking control by a tracking adjustment mechanism is executed. , So as to follow the track continuously.

When the target track position for recording or reproduction is different from the track position currently being scanned, if the difference between the track positions cannot be dealt with only by the tracking control by the tracking adjustment mechanism, the thread feed is performed. The optical pickup is moved to the vicinity of the target track, and thereafter, the target track position is scanned by a track jump by the tracking adjustment mechanism.
When the difference between the target track position and the track position currently being scanned can be dealt with only by tracking control by the tracking adjustment mechanism, the target track position is determined only by the track jump. In any case, the final adjustment of the track scanning position is executed by a track jump by the tracking adjustment mechanism.

[0005]

By the way, when a track jump is performed by the tracking adjustment mechanism, simply jumping to a target track position is difficult.
Actually, there is a problem that reproduction cannot be performed from that position.
That is, data recorded on an optical disc such as a CD or MD or a magneto-optical disc is digital data, and when data recorded on a specific track of the disc is reproduced, the data is already read at the time of scanning that track. A clock for demodulating data must be detected.
Therefore, a PLL for extracting a clock component from reproduced data
Unless the circuit (phase locked loop circuit) locks to the reproduction data and outputs a clock, the data read from the track cannot be reproduced correctly.

For this reason, conventionally, when a track jump is executed, the position to be scanned after the track jump is set to a track position before the target track position. Specifically, when the tracks formed on the disk are spiral and the tracks are sequentially scanned from the inner circumference side, for example, two tracks are set on the inner circumference side from the target track position. . Here, the unit of the number of tracks is one track of the disk as one track (the same applies to the number of tracks described in the following description).

As described above, by causing the track jump to the position on the inner circumferential side of the two tracks from the target position and executing the reproduction from that position, the PL is reproduced during the progress of the two-track reproduction.
When the L circuit is locked to the clock included in the reproduction data, and the target track is actually reproduced, the reproduction data from that track can be correctly decoded.

In recent years, there has been a demand for a disk drive to be able to record and reproduce data at high speed. For example, in the case of continuously reproducing audio data or the like, a so-called 1 × speed reproduction in which the reproduction speed is continuously reproduced at a specified linear speed is performed.
Basically, continuous reproduction of audio data recorded on a disc can be performed. On the other hand, high-speed reproduction such as double-speed reproduction or quadruple-speed reproduction is performed, data is read at high speed, a certain amount of data is stored in a buffer memory in a short time, and the stored data is stored in the buffer memory. If audio is output continuously and the process of performing intermittent data reading such that data is reproduced from the disk again when the remaining amount of data in the buffer memory becomes low, the disk is driven to rotate. Time can be shortened, and power consumption and the like can be reduced.
Further, by changing the reproduction speed continuously according to the remaining amount of data in the buffer memory at that time (for example, continuously changing the reproduction speed in a range from 4 × speed reproduction to 1 × speed reproduction), more effect is obtained. It is also possible to reduce power consumption.

[0009] However, if the reproduction speed changes as in such double speed reproduction or quadruple speed reproduction, there is a problem that the above-described process of jumping inward by a certain number of tracks at the time of track jump cannot be adequately dealt with. there were.
That is, for example, in the case of performing quadruple-speed playback, assuming that the track jump position is two tracks before the target track, the rotation speed of the disk is four times the normal speed, so that the PLL circuit is locked. At the point in time when the data can be stably reproduced, a position beyond the target track position is scanned. For this reason, the track jump must be performed again, and it takes a long time before the data from the target track can be reproduced. It should be noted that when such a disc is reproduced, the PL
The time required for the L circuit to lock hardly changes even if the disk rotation speed (double-speed reproduction speed) changes.

In order to solve this problem, in accordance with the maximum playback speed that can be executed by the disk drive,
All you have to do is decide where you want the track to jump. For example, 4
If the double-speed playback is at the maximum playback speed, the track jump position is set four tracks before the target track. When the four-track playback advances from the track jump position during the quadruple-speed playback, the PLL circuit locks. And it can be played back stably. However, if the reproducing apparatus always performs the quadruple-speed reproduction, such a measure can be taken. However, as described above, when the reproduction speed changes adaptively between the quadruple-speed reproduction and the normal-speed reproduction, At the time of 2 × speed reproduction or 1 × speed reproduction, if the track jump position is four tracks before, it takes a long time until the reproduction proceeds to the target track position. That is,
At the time of 1 × speed reproduction, the jump should be made to the position two tracks before. However, since the jump is made to four tracks, the scanning of two tracks is wastefully performed. The time required for the track jump is wasted and the access speed at the time of the track jump is reduced.

Here, the case where the quadruple speed reproduction is set to the maximum speed has been described. Therefore, the difference in the number of tracks is about two tracks. However, when performing higher speed double speed reproduction, the number of tracks that needlessly be scanned is also reduced. It increases in proportion to the increase in the reproduction speed.

The present invention has been made in view of such a situation, and it is an object of the present invention to enable the position of a track to which a track is jumped at the time of a track jump to be set well even in a disk drive capable of high-speed reproduction. is there.

[0013]

According to the present invention, there is provided a method for controlling a laser beam irradiation position on a disk by an optical pickup by controlling a laser beam irradiation position to jump to a target predetermined track position. A jump is made to a position which is scanned by a predetermined distance ahead of the target track position, and the predetermined distance to be jumped ahead is variably set according to the rotation speed of the disk set by the spindle servo means. It was done.

According to the present invention, the position at which the track jumps is variably set in accordance with the rotation speed of the disk, so that it is possible to jump to an appropriate preceding position according to the rotation speed at that time.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described.
This will be described with reference to the accompanying drawings.

FIG. 1 is a diagram showing a configuration example of the disk drive device of the present embodiment. In this example, MD (Mini Disc)
This is an example of a disk drive for recording and / or reproducing data on an optical disk or a magneto-optical disk having a format referred to as a "disk drive", and here, a disk drive for recording or reproducing audio data. In the format called MD, tracks are spirally formed on the disk starting from the inner circumference side. When a magneto-optical disk is used as a medium, wobbling is applied to the magneto-optical disk. The track address (sector address) is recorded in advance according to the so-called meandering state of the track. In the MD format, an absolute address on a track is set as a sector address.
In this embodiment, a description will be given as a track address.

Disk 1 mounted on disk drive
Is driven to rotate by a spindle motor 11. In this case, with respect to the rotation speed control of the disk 1, in this case, a constant linear speed control (CLV control) is performed, and the rotation speed is controlled by a drive circuit 19 described later to be constant. Speed control is performed. However, if the reproduction at a constant linear velocity specified by the format is 1 × speed reproduction, the reproduction can be performed by varying the reference linear velocity in the range from 1 × speed reproduction to 4 × speed reproduction. .

Recording and reproduction on the disk 1 are performed by irradiating the disk with laser light from the optical pickup 12. When irradiating the laser beam, the signal is focused on the signal recording surface on the disk and irradiated. An optical component such as a lens for irradiating the laser light is driven by a tracking coil attached to the optical pickup 12 so as to adjust the position of the disk in the radial direction. The track jump described later is realized by driving by the tracking coil. The focus position can be adjusted by driving a lens by a focus coil attached to the optical pickup 12. During recording when the disk 1 is a magneto-optical disk, a process of generating a recording magnetic field using a magnetic field modulation coil (not shown) and then heating the signal recording portion with laser light to perform recording is performed.

The optical pickup 12 is configured to be movable in the radial direction from the innermost track forming position of the disk 1 to the outermost track forming position by the thread feed mechanism 13. This thread feed mechanism 13
Is driven by, for example, a pulse motor.

The return light of the laser light radiated from the optical pickup 12 to the signal recording surface of the disk 1 is divided and detected by a detection unit (not shown) in the optical pickup 12.
The signals divided and detected by the respective detection units and output are supplied to a high-frequency circuit (hereinafter referred to as an RF circuit) 14, where the reproduction signal RF, the tracking error signal TE, and the address signal The component ADIP is obtained.
The reproduction signal RF is a signal for reproducing data recorded on the track of the disk, and includes an address signal component AD.
IP is a signal obtained by detecting the wobbling component of the track described above. Here, other signals such as a focus error signal are omitted.

The signal output from the RF circuit 14 is supplied to a digital signal processor (hereinafter referred to as DSP) 15. The DSP 15 performs a demodulation process of a supplied signal, a correction process of characteristics, and the like. That is, the RF circuit 1
The RF signal supplied from 4 is decoded in the DSP 15, and the decoded reproduced data is supplied to the output terminal 18. In this case, the clock component included in the RF signal is supplied to the reproduction data demodulation PLL circuit 16, the PLL circuit 16 outputs a frequency signal synchronized with the clock of the reproduction data, and the DSP 15 synchronizes the data with the clock. Perform decoding. Audio data recorded on the disc of this example is EFM (so-called 8-1).
4), and performs decoding from the EFM modulation. ATRAC (registered trademark) (Compressive T
Decoding from the ransform Acoustic Coding method may be performed in the DSP 15. Note that DSP1
5 has a built-in memory (not shown) for temporarily storing reproduction data, and controls reproduction from the disc 1 so that the data storage amount of the memory is within a certain range during reproduction. It is.

The address signal component ADIP supplied from the RF circuit 14 to the DSP 15 is decoded in the DSP 15 and then the optical pickup 12
Detects the address of the track being scanned. In this case, the clock component included in the address signal component ADIP is supplied to the address demodulation PLL circuit 17, and the PLL circuit 17 outputs a frequency signal synchronized with the clock of the reproduction data. Is decoded. The decoded track address is supplied to a CPU 20 described later. Also, regarding the information as to whether the PLL circuits 16 and 17 are locked,
It is supplied to the CPU 20.

The tracking error signal supplied from the RF circuit 14 to the DSP 15 is supplied to a digital filter in the DSP to perform phase compensation, and the phase-compensated tracking error signal is supplied to a servo control drive circuit 19. To supply.

When each output of the RF circuit 14 is an analog signal, it is converted into a digital signal by an analog / digital converter (not shown) and then input to the DSP 15.

On the basis of the tracking error signal supplied from the DSP 15 to the drive circuit 19, the drive circuit 19 generates a drive signal (voltage signal) to be supplied to the tracking coil of the optical pickup 12, and generates a drive signal (voltage signal) on the track formed on the disk 1. A tracking servo to follow is performed. When a track jump command is sent from the central control unit (CPU) 20 of the disk drive to the drive circuit 19, a drive signal for executing the corresponding track jump is supplied to the tracking coil. When the track jump is executed, the CPU 20 can determine how many tracks on the disk the scanning position of the laser beam straddles, for example, from a change in a tracking error signal at that time.

The drive signal supplied to the sled feed motor provided in the sled feed mechanism 13 also
The thread servo is generated by the drive circuit 19. Further, a drive signal to be supplied to the spindle motor 11 is also generated by the drive circuit 19. The drive circuit 19 detects the rotation speed of the spindle motor 11 by detecting means (not shown),
A spindle servo for stabilizing the rotation speed is performed. These thread servos and spindle servos are also executed based on instructions from the CPU 20.

The CPU 20 is a means for controlling the disk drive of the disk drive, and controls the track position accessed by the optical pickup 12,
The control of the reproduction speed in the range from the double speed reproduction to the quadruple speed reproduction is also executed under the control of the CPU 20. The CPU 20 appropriately controls the playback speed based on, for example, the remaining capacity of the memory for temporarily storing playback data built in the DSP 15. For example, when the amount of data stored in the memory is relatively small, high-speed reproduction such as quadruple-speed reproduction is performed to increase the amount of data stored in the memory. When the amount of data stored in the memory is relatively large, 1-time reproduction is performed. The playback is performed at a relatively low speed, such as a playback speed of 2.times. Further, when a certain amount of reproduction data is stored in the memory, control for temporarily stopping reproduction from the disk is performed until the amount of data stored in the memory decreases to a certain amount. The track address data decoded by the DSP 15 is supplied to the CPU 20 so that the optical pickup 12 can determine the track position during scanning.

Next, in the disk drive of this embodiment, the CPU
An access control process for reproducing or recording on an arbitrary track of the disc 1 under the control of the control 20 will be described with reference to the flowchart of FIG. First, when it becomes necessary to access a track at a predetermined address (target address) of the disk 1 under the control of the CPU 20, the CPU 20
20 determines the address of the track currently being scanned by the optical pickup 12 (step 101). It is determined whether or not the current address determined at this time matches the address (target address) of the track for which access is requested (step 102). If the current address matches the target address in this determination, it is determined that the access has been completed, and the track is scanned from that position to reproduce (or record).

If it is determined in step 102 that the addresses do not match and the access has not been completed, the moving distance is calculated from the difference between the current address and the target address (step 103). It is determined from the travel distance whether or not thread feed is necessary (step 1).
04). If it is determined that the thread feed is necessary, the CPU 20 sends a thread feed command to the drive circuit 19 to execute the thread feed so as to scan the vicinity of the target address (step 105).
After the thread feed is executed, it is determined whether or not the address demodulation PLL circuit 17 is locked to the address signal component ADIP detected from the track scanned by the optical pickup 12 (step 106).
It waits until the circuit 17 is locked. P for address demodulation
When the LL circuit 17 locks, the track address can be decoded, and the CPU 20 can determine the track address. When the lock is detected in step 106, the process returns to step 101, and the CPU 20 determines the address of the track currently being scanned.

On the other hand, when it is determined in step 104 that thread feeding is not necessary based on the movement distance calculated in step 103, a track jump is executed. When executing this track jump, the CPU 20 first determines the current rotation speed of the disk by the spindle motor 11, determines the correction amount of the track jump corresponding to the rotation speed, and determines the track position of the target address by the determined correction amount. The position shifted to the side to be scanned earlier (the inner side in this case) is set as the position where the track jump is performed, and the number of tracks to be track jumped is determined (step 108). A specific example of this correction amount will be described later. Then, a track jump is executed by the number of tracks determined in step 108 (step 109).

After this track jump is executed,
In step 106, it is determined whether or not the address demodulation PLL circuit 17 is locked to the address signal component ADIP detected from the track scanned by the optical pickup 12 after the track jump (step 106).
The process waits until the PLL circuit 17 is locked. When the lock is detected, the process returns to step 101, and the CPU 20 determines the address of the track currently being scanned.

Referring to FIG. 3, a situation in which when a track jump is executed, PLL circuits 16 and 17 are locked by a signal read from the track where the track jump has been performed and data can be decoded with reference to FIG. explain. FIG. 3A shows a process of decoding the ADID data read from the disk and reading the track address. When the track address is at a high level, it indicates that the address can be decoded and read. .
FIG. 3B shows audio data (E
This shows processing until decoding of FM-modulated data: EFM data) and reading of recorded data. When it is at a high level, it indicates that EFM data can be decoded and read. .

P for clock generation after track jump
The timing for turning on (operating) the LL circuits 16 and 17 is set to be the same. At this time, the timing at which the PLL circuit 17 locks the data read from the disk and makes it possible to decode the address from the APID data is determined by the timing at which the PLL circuit 16 locks the data read from the disk and the EFM data. Is earlier than the timing at which it can be decoded. Here, the time from the turning on of the PLL circuit to the locking after the track jump does not substantially depend on the rotation speed of the disk at that time, and is a substantially constant time. Specifically, for example, in a certain disk drive, the time from the track jump until the PLL circuit 17 locks and the address can be decoded is about 0.04 seconds, and after that the PLL circuit 16 locks. Requires about 0.03 seconds.

In the present embodiment, the time from when the track jump is performed until the PLL circuit 17 locks the data read from the disk until the address can be decoded from the APID data is described above. 2
When the track jump is executed in step 109 of the flowchart of FIG. 7, the time is used as a reference time for determining the correction amount in step 108.

That is, in the correction processing of the number of track jumps in step 108, the track jump is made to a position shifted by a correction amount to the side to be scanned (the inner side in this case) ahead of the track position of the target address. The time required for the laser light from the optical pickup to scan the number of tracks to be added as the correction amount is locked by the PLL circuit 17 after the track jump shown in FIG. 3A, so that the track address can be read. Set the time until it becomes

Here, in the case of this embodiment, as described above, the reproduction speed (disc rotation speed) is continuously changed within the range from 1 × speed reproduction to 4 × speed reproduction as the disk rotation speed. The scanning distance of the laser beam from the optical pickup changes within a certain time depending on the disk rotation speed at that time. That is, when the disk rotation speed is high, the number of tracks scanned by the laser light from the optical pickup within a certain period of time increases, and when the disk rotation speed is low, the laser beam from the optical pickup within a certain time period The number of tracks scanned by light is reduced. Therefore, when the CPU 20 sets the correction amount in step 108, the CPU 20 determines the disk rotation speed (rotation speed of the spindle motor) at that time and determines the number of tracks to be added as the correction amount by the laser light from the optical pickup. A process for variably setting the correction amount is performed so that the scanning time becomes constant.

FIG. 4 is a diagram showing the correspondence between the optimum correction amount at the time of the track jump and the rotation speed of the spindle motor in the case of this embodiment. Here, the correction amount is indicated by the number of tracks, and the change range of the spindle rotation speed at the time of 1 × speed reproduction is range S1, and the change range of the spindle rotation speed at the time of 2 × speed reproduction is range S2. Are shown as a range S3 and a change range of the spindle rotation speed at the time of 4 × speed reproduction is shown as a range S4. In the case of this example, since the reproduction is performed by the linear velocity constant control (CLV control) as described above, when scanning the track on the inner circumference side of the disc, and scanning the track on the outer circumference side of the disc, the spindle is used. Since the rotation speed changes, the spindle rotation speed changes at each reproduction speed, and the track jump correction amount may need to be changed between the inner circumference side and the outer circumference side of the disc.

A specific example of the correction amount will be described with reference to FIG. 4. The range S1 at 1 × speed reproduction is substantially one track or less, and the correction amount of one track is set at any track position. In the 2 × speed reproduction indicated by the range S2, when the spindle rotation speed is slow in the outer track, a correction amount of one track is set, and in the track position on the inner circumference side from a certain radial position, the correction amount of two tracks is set. Set the correction amount. In the case of the triple speed reproduction indicated by the range S3, when the spindle rotation speed is slow in the outer track, the correction amount of two tracks is set, and in the track position on the inner circumference side from a certain radial position, the correction amount of three tracks is set. Set the correction amount. In the case of the quadruple speed reproduction indicated by the range S4, when the spindle rotation speed is slow in the outer track, the correction amount for two tracks is set, and the correction amount for three tracks is set from a certain radial position to the inner track position. Is set, and a correction amount for four tracks is set at a track position on the inner peripheral side from another certain radial position. The following [Table 1]
Is a numerical value of the correction amount in FIG.

[0039]

[Table 1]

Actually, as shown in FIG. 4, the correction amount of the track jump has a linear relationship with the spindle rotation speed, and the CPU 20 determines only the rotation speed of the spindle motor to obtain an accurate correction track. The number of jumps can be set, and there is no need for the CPU 20 to determine the reproduction speed at that time. However, in order to simplify the arithmetic processing for setting the number of correction track jumps, the number of correction tracks may be determined from the reproduction speed at that time and the approximate thread position of the optical pickup. Alternatively, the number of correction tracks may be uniquely determined from the reproduction speed at that time without determining the thread position. For example, the correction amount is 1 track at 1 × speed reproduction, the correction amount is 2 tracks at 2 × speed reproduction, the correction amount is 3 tracks at 3 × speed reproduction, and the correction amount is 4 tracks at 4 × speed reproduction, and the correction amount is fixed at reproduction double speed. A value may be set.

As described above, in this embodiment, when a track jump is executed, a target track position is scanned ahead by the number of tracks set according to the disk rotation speed at that time. By correcting the position, the scanning track at the time when the track address is read out after the execution of the track jump becomes the target track position, no matter what the disk rotation speed is set. And quick access to the truck.

In this case, in the present embodiment, the time at which the track address recorded by wobbling of the track formed on the disk can be decoded is used as a reference.
Since the number of correction tracks is set, the track address can be determined immediately after access, and the access time can be set to the minimum time.

In the above description, the correction amount of the track jump is set in the range from one track to four tracks from the results of FIG. 4 and [Table 1]. The track jump may be performed on the inner circumference side so as to allow some time before decoding can be performed.

Further, in the above-described embodiment, the number of correction tracks is set based on the time until the track address can be decoded. However, actual correction of audio data (EFM data) and the like recorded on a disk is performed. The number of correction tracks may be set based on the time until data can be decoded. In this case, the number of correction tracks slightly increases from the number of tracks described above.

In the configuration of the apparatus described in the above-described embodiment, the configuration for processing the recording data is omitted. However, when the data recording requires a track jump, the recording data is similarly processed. Based on the data recording speed (spindle rotation speed) at that time, the amount of correction of the track jump position is determined, and control for executing the track jump can be performed.

Also, in the above-described embodiment, the disk drive device in which the reproduction speed (recording speed) changes in the range of 1 × to 4 × speed has been described, but the present invention is also applicable to a disk drive device in which the speed change range is larger. Of course, you can.

In the above-described embodiment, an example is described in which the present invention is applied to a disk drive device for recording or reproducing a magneto-optical disk or an optical disk called an MD (mini disk). The present invention can be applied to other disk drive devices in which a jump is performed.

[0048]

According to the present invention, the track jump position is variably set in accordance with the rotational speed of the disk, so that it is possible to jump to an appropriate preceding position according to the rotational speed at that time. Therefore, regardless of the disk rotation speed at the time of the track jump, the time from when the track jump position is scanned to when the target track position is scanned should be set to a substantially constant time. This makes it possible to uniformly set the time required to reach the target track position at the time of the track jump, so that it does not take much time for the track jump due to the disk rotation speed.

In this case, a predetermined distance to be additionally scanned at the time of a track jump is secured by a PLL circuit for locking to a clock component included in a signal obtained from the return light detected by the optical pickup, and the time required for locking is secured. By setting the scanning distance, the target track position is scanned when the PLL circuit is locked after the track jump, and data can be read from the disk after the track jump at a uniform timing. Will be able to do it.

The disk mounted on the disk mounting portion is a disk on which address information is recorded by meandering of tracks, and a predetermined distance to be additionally scanned during a track jump is obtained from return light detected by an optical pickup. The PLL circuit locks to the clock component of the information recorded by the meandering of the track, which is included in the signal, and has a scanning distance that secures the time required for locking, so that the PLL circuit locks after a track jump. At that point, scan the target track position,
The address of that track position can be determined,
After the track jump, determine the disc address,
Data can be read from the track at the determined address position at a uniform timing.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of a disk drive device according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a processing example at the time of access according to the embodiment of the present invention;

FIG. 3 is an explanatory diagram showing an example of a data read state after a track jump according to one embodiment of the present invention;

FIG. 4 is a characteristic diagram showing a correspondence relationship between a spindle rotation speed and a track jump correction amount according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Disc, 11 ... Spindle motor, 12 ... Optical pickup, 13 ... Thread feed mechanism, 14 ... High frequency circuit (RF circuit), 15 ... Digital signal processor (DSP), 16 ... PLL circuit for reproduction data demodulation, 17
... PLL circuit for address demodulation, 18 ... reproduced data output terminal, 19 ... drive circuit, 20 ... central control unit (C
PU)

Claims (3)

[Claims] A disk mounting unit; a spindle motor for driving a disk mounted on the disk mounting unit to rotate; a spindle servo unit for controlling a rotation speed of the disk by the spindle motor; and a disk mounted on the disk mounting unit. An optical pickup that irradiates a laser beam to a track formed on the disc and detects return light from the disc; a tracking servo unit that sets an irradiation position of the laser light from the optical pickup to the disc; and the optical pickup When the laser beam irradiation position on the disk is controlled, and the laser beam irradiation position is track-jumped to the target track position under the control of the tracking servo means, the laser beam is scanned ahead of the target track position by a predetermined distance. Jump to the position
A disk drive device comprising: control means for variably setting the predetermined distance to jump ahead in accordance with the rotation speed of the disk set by the spindle servo means. 2. The disk drive according to claim 1, wherein said predetermined distance is a phase locked loop circuit for locking to a clock component included in a signal obtained from return light detected by said optical pickup. Disk drive, which is the scanning distance to ensure the time it takes to perform. 3. The disk drive according to claim 1, wherein the disk mounted on the disk mounting portion is a disk on which address information is recorded by meandering of a track, and the predetermined distance is detected by the optical pickup. A phase locked loop circuit that locks to the clock component of the information recorded by the meandering of the track, which is included in the signal obtained from the returned return light, and the disk drive that is the scanning distance that secures the time required for locking. apparatus.