JP2002117615A - Disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable rapid shift to the signal processing, based on a laser beam after the completion of a seek. SOLUTION: When an optical pickup 12 is moved to another zone during recording/reproducing of a magneto-optical disk 12 of a ZCLV system (during seek), a DSP 40 rotates a spindle motor 52 at the optimum rotating speed corresponding to the zone at a moving destination in accordance with the FG pulse outputted from a motor driver 54. When the optical pickup 12 arrives at a desired track belonging to the zone of the moving destination, the DSP 40 rotates a spindle motor 52 based on the FCM signal outputted from an FCM signal detecting circuit 28. The spindle motor 52 rotates at the optimum rotating speed, corresponding to the zone of the moving destination.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk drive, and more particularly to, for example, a plurality of areas having mutually different optimum rotational speeds are allocated to a recording surface, a track is formed on the recording surface, and a predetermined area is provided on the track at predetermined intervals. The present invention relates to a disk device that rotates a disk recording medium on which a mark is formed by a spindle motor and irradiates a recording surface with a laser beam by an optical pickup to detect a predetermined mark signal related to the predetermined mark.

[0002]

2. Description of the Related Art ASMO (Advanced Storage Magneto O
In the case of a magneto-optical disk such as a ptical disc, the rotation speed is determined by ZCLV (Zone Constant Linear Velocity).
The method is adopted. For this reason, in each of a plurality of zones (areas) formed on the recording surface, the angular velocity needs to be constant. In ASMO, FCM (Fine Clock
Mark) is formed at a predetermined interval on the track, so that the FC based on the reflected light when tracing the FCM is used.
Various operations such as the disk rotation speed can be controlled by the M signal.

Therefore, in a conventional disk drive, F
At the time of recording / reproduction that can detect the CM signal, the disk rotation speed is controlled based on the FCM signal (FCM control),
At the time of seek in which the M signal cannot be detected, the disk rotation speed is controlled based on the FG signal output from the spindle motor (FG control).

[0004]

However, if there is a discrepancy between the disk rotation speed during the FCM control and the disk rotation speed during the FG control, the FCM control and the FG control are performed when the optical pickup is moved to a desired zone by a seek operation. Switching between and is not performed smoothly. As a result, when the FCM control is restarted in a desired zone, it takes time for the disk rotation speed to stabilize, and there is a problem that it is not possible to quickly shift to signal processing based on laser light.

[0005] Further, if tracking is lost during recording / reproduction and the FCM signal is no longer detected, FCM control becomes impossible and the spindle motor may run away.

SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide a disk device which can promptly shift to signal processing based on laser light when an optical pickup reaches a desired area.

Another object of the present invention is to provide a disk drive capable of preventing runaway of a spindle motor when tracking error occurs.

[0008]

According to a first aspect of the present invention, a plurality of areas having mutually different optimum rotational speeds are allocated to a recording surface, a track is formed on the recording surface, and a predetermined mark is formed on the track at a predetermined distance. In a disk drive for rotating a recorded disk medium by a spindle motor and irradiating a recording surface with a laser beam by an optical pickup to detect a predetermined mark signal related to a predetermined mark, a speed related to a rotation speed of the spindle motor is used. Generating means for generating a signal, moving means for moving the optical pickup in the radial direction of the disk recording medium so that laser light is irradiated on a desired track included in another area, when moving the optical pickup by the moving means, Spindle motor with optimal rotation speed corresponding to another area based on speed-related signals First rotation control means for rotating the optical pickup; and second rotation control means for rotating the spindle motor at an optimum rotation speed corresponding to another area based on a predetermined mark signal when the optical pickup reaches a desired track. A disk device characterized by the following.

According to a second aspect of the present invention, there is provided a disk for irradiating a laser beam onto a track while rotating a disk recording medium having a track formed on a recording surface and a predetermined mark formed on the track at predetermined distances by a spindle motor. In the apparatus, first detecting means for detecting a predetermined mark signal related to a predetermined mark based on reflected light from a track, generating means for generating a speed-related signal related to a rotation speed of a spindle motor, a predetermined mark signal and a speed-related signal Selection means for selecting one of the signals, rotation speed control means for controlling the rotation speed based on the selection signal from the selection means, and determination of the presence / absence of laser beam de-tracking when the predetermined mark signal is selected by the selection means. The speed-related signal is selected by the discriminating means and the selecting means when tracking loss occurs. Characterized in that it comprises a selection control unit for a disk apparatus.

[0010]

In the first aspect of the present invention, tracks are formed on the recording surface of the disk recording medium, and a plurality of areas having mutually different optimum rotational speeds are allocated. Also, a predetermined mark is formed on the track at a predetermined distance. The spindle motor rotates such a disk recording medium, and the optical pickup irradiates the recording surface of such a disk recording medium with laser light. By irradiation with the laser beam, a predetermined mark signal related to the predetermined mark is detected.

When it is desired to irradiate a desired track included in another area with the laser beam, the moving means moves the optical pickup in the radial direction of the disk recording medium. At this time, the first rotation control means rotates the spindle motor at the optimum rotation speed corresponding to the destination area based on the speed-related signal (related to the rotation speed of the spindle motor) generated by the generation means. When the optical pickup reaches a desired track belonging to the destination area,
Second rotation control means rotates the spindle motor based on the predetermined mark signal. The spindle motor rotates at an optimum rotation speed corresponding to the destination area.

The predetermined mark is preferably an embossed mark.

In the second invention, a track is formed on a recording surface of a disk recording medium, and a predetermined mark is formed on the track at a predetermined distance. The spindle motor rotates such a recording medium, and the track is irradiated with laser light. The first detecting means detects a predetermined mark signal related to the predetermined mark based on the reflected light from the track, and the generating means generates a speed-related signal related to the rotation speed of the spindle motor. The rotation control means controls the rotation speed of the spindle motor based on the predetermined mark signal when the predetermined mark signal is selected by the selection means. The rotation speed of the spindle motor is controlled based on the rotation speed. The presence / absence of laser beam de-tracking is determined by the determination means when the rotation speed is controlled by the predetermined mark signal. When tracking loss occurs, the selection control means causes the selection means to select a speed-related signal. The rotation speed of the spindle motor is controlled based on a speed-related signal.

When the tracking error signal is detected by the second detecting means based on the reflected light from the track,
The determining means compares the detected level of the tracking error signal with a predetermined level to determine the presence or absence of tracking error.

Here, the predetermined mark is preferably a mark embossed on a track.

[0016]

According to the first invention, when the optical pickup is moved in the radial direction of the disk recording medium, the spindle motor is rotated at an optimum rotation speed corresponding to the destination area based on the speed-related signal. I made it. Therefore, when the optical pickup reaches a desired area, the rotation speed of the spindle motor has reached near the optimum rotation speed, and it is possible to promptly shift to signal processing based on laser light.

According to the second aspect of the present invention, when tracking loss occurs during rotation speed control based on a predetermined mark signal,
Since the control is switched to the rotation speed control based on the speed-related signal, runaway of the spindle motor can be prevented.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0019]

Referring to FIG. 1, an optical disk device 10 of this embodiment includes an optical pickup 12 provided with an optical lens 14. The optical lens 14 is supported by the tracking actuator 16 and the focus actuator 18, and the laser light emitted from the laser diode 20 is converged by such an optical lens 14 and is
O is irradiated on the recording surface of the magneto-optical disk 48 such as O.
As a result, desired data is recorded on or reproduced from the magneto-optical disk 48.

The magneto-optical disk 48 adopts the ZCLV system, and a plurality of zones (areas) 0 to 13 are formed on the recording surface from the outer periphery to the inner periphery as shown in FIG.

[0021]

[Table 1]

Referring to Table 1, as long as they belong to the same band, the number of frames per track is the same, but if the band is different, the same number of frames is not guaranteed.
Since the length of one track is shorter on the inner circumference than on the outer circumference, the number of frames per track decreases from the outer circumference toward the inner circumference. Further, in each zone, one frame is 2048 bytes,
The data transfer rate during recording / reproduction needs to be constant regardless of the zone. For this reason, the rotation speed (optimum rotation speed) of the magneto-optical disk 50 increases from the outer periphery toward the inner periphery.

As shown in FIG. 3, on the surface of the magneto-optical disk 48, convex land tracks and concave groove tracks are formed alternately every other track, and FCMs are arranged at predetermined intervals on each track. Embossed.
That is, the FCM on the land track is formed in a concave shape,
The FCM on the groove track is formed in a convex shape. Note that the number of FCMs allocated to one frame is 3 for both the land track and the groove track.
There are nine.

Returning to FIG. 1, the reflected light from the recording surface passes through the optical lens 14 and is irradiated on the photodetector 22. The output of the photodetector 22 is supplied to the FE signal detection circuit 24 and TE
The signals are input to the signal detection circuit 26, and the FE signal (focus error signal) and the TE signal (tracking error signal) are detected respectively. The detected FE signal and T
The E signal passes through A / D converters 38a and 38b,
The signals are provided to a DSP (Digital Signal Processor) 40, respectively.

The DSP 40 executes focus servo processing based on the FE signal, and executes tracking servo processing based on the TE signal. A focus actuator control signal is generated by the focus servo processing, and D
Actuator 1 via the A / A converter 42a
8 is output. Further, a tracking actuator control signal and a thread control signal are generated by the tracking servo processing, and the D / A converter 42b and the PWM
From the signal generation circuit 42c to the tracking actuator 1
6 and the thread motor 44.

The output of the photodetector 22 is also input to the FCM signal detection circuit 28. The FCM signal detection circuit 28 generates a fine clock mark signal (FCM signal) based on the reflected light of the FCM formed on the magneto-optical disk 48. The FCM signal changes as shown in FIG. 4A when the laser beam follows the land track, and changes as shown in FIG. 4C when the laser beam follows the groove track.

The generated FCM signal is a VCA (Voltag
e Control Amplifier) 30 to a peak hold circuit 32. The peak hold circuit 32 is an FCM
The peak level of the signal is detected, and FIG.
In (C), a peak hold signal indicated by a chain line is output. The output peak hold signal is provided to the DSP 40 via the A / D converter 38c.

The DSP 40 generates a gain control signal for controlling the gain of the VCA 30 and a slice signal for slicing the FCM signal based on the input peak hold signal. The gain control signal is supplied to the VCA 30 via the D / A converter 42e, and the slice signal is supplied to the D / A converter 4e.
The signal is supplied to the comparator 34 via 2d. The slice signal is the level of the peak hold signal (peak level)
Is multiplied by a predetermined value α (0 <α <1).
It has a slice level indicated by a dotted line in FIG.

The comparator 34 includes a variable gain amplifier 30
Of the FCM signal output from the D / A converter 42
Then, the level of the slice signal output from e is compared.
If FCM level> slice level, a high level signal is output, and if FCM level ≦ slice level, a low level signal is output. As a result, FIG.
4B for the FCM signal shown in FIG. 4B, and FIG. 4D for the FCM signal shown in FIG.
Are output from the comparator 34.
The rising cycle of this comparison signal matches the cycle of the FCM signal, and this comparison signal is defined as an FCM pulse.

The frequency dividing circuit 36 divides the frequency of the FCM pulse output from the comparator 34 by 39. As mentioned above,
Since 39 FCMs are allocated per frame,
The output (divided pulse) of the divider 36 rises for each frame. Such frequency-divided pulses are input to the DSP 40 via a pulse width counter (PWC) 38d.

The magneto-optical disk 48 is mounted on a spindle 50, and the spindle 50 has a spindle motor 52
Supported by The spindle motor 52 is driven by a motor driver 54, and with the rotation of the spindle motor 52, the spindle 50 and thus the magneto-optical disk 48 rotate. The driver 54 is a spindle motor 5
2, and outputs an FG pulse related to this rotation speed to the DSP 40.

The DSP 40 controls the driver 54 based on the frequency-divided pulse output from the PWM 38 d or the FG pulse output from the driver 54.
Generate a pulse. That is, when the tracking control is performed normally and the FCM signal is detected, a PWM pulse is generated based on the frequency-divided pulse (FCM control). When the tracking is lost and the FCM signal is not detected, A PWM signal is generated based on the FG pulse (FG control). The driver 54 rotates the spindle motor 52 at a speed corresponding to the pulse width of the generated PWM pulse.

Since the FCM is formed at a predetermined interval regardless of the band, when the FCM signal is detected (FCM
At the time of CM control), if the pulse width of the PWM pulse is controlled so that the period of the frequency division pulse becomes a predetermined value, the spindle motor 52 rotates at an optimum speed for each band. On the other hand, since the period of the FG pulse is related to the rotation speed of the spindle motor 52, when the FCM pulse is not detected (during FG control), the pulse width of the PWM pulse is used only with the FG pulse (that is, the rotation of the spindle motor 52). Speed) cannot be properly controlled. Therefore, as shown in FIG. 5, a table 46a in which a band and a target FG cycle are associated is prepared in advance in an internal memory of a CPU (system controller) 46, and a target FG corresponding to a desired band is prepared.
The cycle is set in the DSP 40 by the CPU 46.
At the time of the FG control, the DSP 40 controls the pulse width of the PWM pulse based on the FG pulse given from the motor driver 54 and the target FG cycle set by the CPU 46. Note that the target FG cycle shown in FIG. 5 is represented by a hexadecimal number.

The FCM signal cannot be detected not only when the tracking error occurs unintentionally due to vibration or the like, but also when moving to another band (when seeking). As described above, there is no guarantee that the optimum rotational speed of the destination band is the same as the optimal rotational speed of the current band. For this reason, when the pulse width of the PWM pulse is controlled based on the target FG cycle corresponding to the band before the movement when moving to another band, the rotation speed immediately after the completion of the movement and the optimum rotation speed in the destination band are determined. A gap occurs between them.
For example, when moving from band 0 to band 6 by a seek command, the target FG cycle of band 0 “297FH”
When the pulse width of the PWM pulse is controlled on the basis of the above, the rotation speed of the spindle motor 52 immediately after reaching the band 6 remains at 1920 rpm, and there is a shift of 380 rpm from the rotation speed of the band 6 at 2300 rpm. Then, it takes time to adjust the rotation speed to the movement destination band by the FCM control after the movement is completed.

In order to solve such a problem, in this embodiment, a target FG cycle corresponding to a target band is set in the DSP 40 prior to the start of a seek, and the DSP 40
The pulse width of the PWM pulse is controlled based on the set target FG cycle. Thereby, the spindle motor 52
Changes as shown in FIG. 7 (A) or FIG. 8 (A). Note that FIG. 7B and FIG.
FIG. 6 is a waveform chart showing an E signal.

FIG. 7 shows a case in which the optimum rotation speed of the destination band is faster than the optimum rotation speed of the band before the movement.
The rotation speed of the spindle motor 52 rapidly increases with the start of the FG control, and reaches the optimum rotation speed of the destination band during the FG control. When the seek is completed and the control returns to the FCM control, the spindle motor 52 continues to rotate at the rotation speed before the return. FIG. 8 shows a case where the optimum rotation speed of the band at the movement destination is faster than the optimum rotation speed of the band before movement. At this time, the rotation speed of the spindle motor 52 rapidly decreases with the start of the FG control. When the optical pickup 12 reaches the target band, the rotation speed of the spindle motor 52 is stable, and maintains the same rotation speed even after returning to the FCM control.

As described above, since the rotation speed of the spindle motor 52 is controlled based on the target FG cycle of the destination band, recording / reproducing can be started immediately after reaching the destination band. it can.

The photodetector 22, the FE signal detection circuit 2
4, TE signal detection circuit 26 and FCM signal detection circuit 2
8 is configured as shown in FIG. The photodetector 22 is 4
And two detection elements 22a to 22d.
The outputs of 2a to 22d are subjected to different calculations in the FE signal detection circuit 24, the TE signal detection circuit 26, and the FCM signal detection circuit 28. Specifically, Equation 1 is calculated in the FE signal detection circuit 24, and the TE signal detection circuit 2
Equation 6 is calculated in 6 and Equation 3 is calculated in the FCM signal detection circuit 28. Note that “A” to “D” in Equations 1 to 3 correspond to outputs of the detection elements 22a to 22d, respectively.

[0039]

FE = (A + C)-(B + D)

[0040]

Equation 2 TE = (A + D)-(B + C)

[0041]

FCM = (A + B)-(C + D) CPU46
Operates in accordance with the flowcharts shown in FIGS. 9 and 10, and the DSP 40 operates in accordance with the flowcharts shown in FIGS. Note that the DSP 40 is actually formed by a logic circuit, but for convenience of description, a flowchart is used.

Referring to FIG. 9, when power is turned on, CPU 46 resets the focus control flag and the tracking control flag in step S1. The setting / reset of the focus control flag requests the DSP 40 to execute / interrupt the focus servo, and the set / reset of the tracking control flag requests the DSP 40 to execute / interrupt the tracking servo. Therefore, in step S1, the DSP 40 is requested to interrupt the focus servo and the tracking servo.

Subsequently, the CPU 46 sets the target FG cycle (= 1A48H) in the DSP 40 in step S3, and sets the FG flag in step S5. “1A48H”
Is the target FG cycle of band 0 assigned to the outermost periphery of the magneto-optical disk 48. The set state of the FG flag requests a transition from the FCM control to the FG control, and the reset state of the FG flag changes from the FG control to the FCM control.
It is required to shift to control. Therefore, the execution of the FG control is requested to the DSP 40 by the process of step S5.

In step S7, the DSP 40 is instructed to move the optical pickup 12 to the outermost periphery of the magneto-optical disk 48. In subsequent steps S9 and S11, the motor driver 54 and the laser diode 20 are activated, respectively.
When the optical pickup 12 reaches a destination (a destination track), the DSP 40 outputs an arrival notification to the CPU 46. In step S13, it is determined whether or not the optical pickup 12 has reached the destination based on the arrival notification.
When the arrival notification is input, the focus control flag and the tracking control flag are set in step S15,
Execute focus servo and tracking servo
Request to SP40.

Thereafter, the CPU 46 determines whether or not a seek command has been given in step S17. Here YES
If so, the destination band is specified in step S19,
In step S21, the target FG cycle corresponding to the movement destination band is detected from the table 46a, and the detected target F
The G cycle is set in the DSP 40 in step S23. When the setting of the target FG cycle is completed, the focus control flag and the tracking control flag are reset in step S25 (requesting suspension of the focus servo and tracking servo), and in step S27, the movement of the optical pickup 12 to the target band is determined by the DSP 40. To order.

On the other hand, when the arrival notification is returned from the DSP 40, it is determined that the destination has been reached in step S29, and the focus control flag and the tracking control flag are set in step S31. That is, the DSP 40 is requested to execute the focus servo and the tracking servo. Upon completion of the process in the step S31, the process returns to the step S17.

The DSP 40 processes the main routine shown in FIG. 11 by a timer interrupt every predetermined time. First, in step S41, it is determined whether or not a movement command has been input from the CPU 46. When a movement command is given from the CPU 46, the process proceeds from step S41 to step S43, in which the thread motor 44 is driven to move the optical pickup 12. When the optical pickup 12 reaches the destination, step S45
Is determined to be YES, and the arrival notification is sent to the CPU in step S47.
Fire at 42.

In step S49, the state of the focus control flag is determined. If it is in the set state, the focus servo is executed in step S51 before proceeding to step S53. If it is in the reset state, the procedure proceeds to step S53. In step S53, the state of the tracking control flag is determined. If it is set here,
In step S55, tracking servo and thread servo are executed. In step S57, tracking error is detected, and the routine returns.

The detection of tracking loss in step S57 follows a subroutine shown in FIG. DSP40
First, the maximum level of the TE signal is detected in step S61, and the detected maximum level is compared with a predetermined threshold in step S63. Here, if the maximum level is greater than the threshold, it is considered that tracking error has not occurred, and step S6 is performed.
After resetting the tracking error flag at 7, the program returns. On the other hand, if TE signal level ≦ threshold, it is considered that tracking loss has occurred, and a tracking loss flag is set in step S65 before returning.

The DSP 40 also has an FG pulse or FC
The spindle control routine shown in FIG. 13 is processed in response to the rise of the M pulse. First, in step S71, FG
Determine the state of the flag. If the FG flag is set, the process proceeds to step S73 to perform FG control. If the FG flag is reset, the process proceeds to step S77 to perform FCM control.

When proceeding to step S73, first, an FG pulse is fetched in this step, and the cycle of the FG pulse is detected. Next, in step S75, a deviation between the target FG cycle and the detected FG cycle is determined. That is, the FG cycle detected in step S73 is subtracted from the target FG cycle set by the CPU 46, and the subtracted value is used as a deviation.
In step S81, the PWM in which the calculated deviation is eliminated
The pulse width is determined, and in the subsequent step S83, a PWM pulse having the determined pulse width is output to the motor driver 54. Thereby, the rotation speed of the spindle motor 50 is corrected.

On the other hand, when the operation proceeds to step S77 for performing the FCM control, first, in this step, the PWC 38
The frequency dividing pulse is fetched from d, and the period of the FCM pulse is detected based on the frequency dividing pulse. Subsequent step S79
Then, a deviation between the target FCM cycle and the detected FCM cycle is obtained. The target FCM cycle is always constant (18E6H in hexadecimal notation), and the deviation is obtained by subtracting the FCM cycle detected in step S77 from such a target FCM cycle. When the deviation is obtained, steps S81 and S81 are executed.
At 83, the same processing as described above is performed.

In each of steps S85 and S87,
The states of the tracking control flag and the tracking loss flag are determined. Then, even if the tracking control flag is in the reset state (tracking servo interrupted) or the tracking control flag is set (tracking servo execution), the tracking-off flag is set in the set state (T
If (E signal maximum level ≦ threshold), it is considered that the FCM control is impossible, and the FG flag is set in step S89. That is, a request is made to shift from FCM control to FG control. On the other hand, if the tracking control flag is in the set state (tracking servo execution) and the tracking error flag is in the reset state (TE signal maximum level> threshold), it is determined that FCM control is possible, and the FG flag is set in step S91. Reset. That is, a request is made to shift from FG control to FCM control. Upon completion of the process in the step S89 or S91, the process returns.

As can be understood from the above description, land tracks and groove tracks are formed on the recording surface of the magneto-optical disk 48, and a plurality of zones having mutually different optimum rotational speeds are allocated. Further, the FCM is formed on the track at every predetermined distance. The spindle motor 52 rotates such a magneto-optical disk 48, and the optical pickup 12 rotates the magneto-optical disk 4
The recording surface of No. 8 is irradiated with laser light. The irradiation of the laser beam detects the FCM signal.

To irradiate a desired track included in another zone with laser light, the DSP 40 moves the optical pickup 12 in the radial direction of the magneto-optical disk 48.
At this time, based on the FG pulse output from the motor driver 54, the DSP 40 rotates the spindle motor 52 at the optimum rotation speed corresponding to the destination zone.
When the optical pickup 12 reaches a desired track belonging to the destination zone, the DSP 40 rotates the spindle motor 52 based on the FCM signal. The spindle motor 52 rotates at an optimum rotation speed corresponding to the destination zone.

As described above, when the optical pickup 12 is moved in the radial direction of the magneto-optical disk 48, the spindle motor 52 rotates at the optimum rotation speed of the destination zone based on the FG pulse. Therefore, the optical pickup 12
Reaches the desired track, the spindle motor 5
The rotation speed of No. 2 has reached near the optimum rotation speed of the zone to which the desired track belongs, and it is possible to quickly shift to signal processing based on laser light. When the tracking control flag becomes 1 after the seek, the FG flag becomes 0, and it is possible to quickly switch from the FG control to the FCM control.

Further, if the tracking error occurs while the rotation speed of the spindle motor 52 is controlled based on the FCM pulse, the DSP 40 selects the FG pulse instead of the FCM signal, and the DSP 40 selects the FG pulse based on the FG pulse. 52 is controlled. Here, the presence or absence of tracking loss is determined by comparing the maximum level of the TE signal with a predetermined threshold. As described above, when tracking loss occurs during the FCM control, the FCM control shifts to F
Since the control is switched to the G control, runaway of the spindle motor 52 can be prevented.

In this embodiment, the ASMO is used as the magneto-optical disk. However, a plurality of areas having mutually different optimum rotational speeds are allocated to the recording surface, and predetermined marks are formed on the track at predetermined intervals. As long as
It is not limited to ASMO.

The magneto-optical disk of this embodiment is a ZC
The LV system is adopted, but ZCAV (Zone C
onstant Angular Velocity).

Further, in this embodiment, when the tracking control is normally performed, the rotation speed of the spindle motor is controlled based on the FCM signal. Embosses are formed at predetermined intervals, and an address mark signal related to this address mark can be detected. Therefore, the rotation speed of the spindle motor may be controlled based on the address mark signal instead of the FCM signal.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is an illustrative view showing a plurality of zones formed on a magneto-optical disk;

FIG. 3 is an illustrative view showing land tracks, groove tracks, and fine clock marks formed on a recording surface of a magneto-optical disk;

FIG. 4A is an FCM detected from a land track.
It is a waveform diagram which shows a signal, (B) is FCM shown in (A).
It is a waveform diagram which shows the FCM pulse based on a signal, (C)
FIG. 4 is a waveform diagram showing an FCM signal detected from a groove track, and FIG. 4D is a waveform diagram showing an FCM pulse based on the FCM signal shown in FIG.

FIG. 5 is an illustrative view showing a table stored in an internal memory of the CPU;

FIG. 6 is a circuit diagram showing a photodetector, a TE signal detection circuit, an FE signal detection circuit, and an FCM signal detection circuit.

FIG. 7A is a waveform diagram showing an example of a change in the rotation speed of a spindle motor, and FIG. 7B is a waveform diagram showing an example of a change in a TE signal.

8A is a waveform diagram showing another example of a change in the rotation speed of the spindle motor, and FIG. 8B is a waveform diagram showing another example of a change in the TE signal.

FIG. 9 is a flowchart showing a part of the operation of the CPU;

FIG. 10 is a flowchart showing another portion of the operation of the CPU;

FIG. 11 is a flowchart showing a part of the operation of the DSP.

FIG. 12 is a flowchart showing another part of the operation of the DSP.

FIG. 13 is a flowchart showing another portion of the operation of the DSP.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Optical disk apparatus 12 ... Optical pick-up 28 ... FCM signal detection circuit 32 ... Peak hold circuit 34 ... Comparator 36 ... Frequency dividing circuit 40 ... DSP 52 ... Spindle motor 54 ... Driver

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shuno Yano 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. F-term (reference) 5D109 KA05 KA12 KB05 KB14 KB27 KD05 KD14 KD37 KD38 KD49 5D118 BA04 BB06 BD04 BF13 CD03 CD07 CF05 CG02

Claims (4)

[Claims] 1. A disk drive comprising: a plurality of areas having different optimum rotational speeds allocated to a recording surface; a track formed on the recording surface; and a predetermined mark formed at predetermined intervals on the track by a spindle motor. A disk device for irradiating a laser beam onto the recording surface by an optical pickup and detecting a predetermined mark signal related to the predetermined mark, wherein a speed-related signal related to a rotation speed of the spindle motor is generated. Moving means for moving the optical pickup in a radial direction of the disk recording medium so that the laser light is irradiated on a desired track included in another area; moving the optical pickup by the moving means Before corresponding to said another area based on said speed related signal First rotation control means for rotating the spindle motor at an optimum rotation speed, and when the optical pickup reaches the desired track, the optical pickup at the optimum rotation speed corresponding to the another area based on the predetermined mark signal. A disk device, comprising: second rotation control means for rotating a spindle motor. 2. A disk drive in which a track is formed on a recording surface and a predetermined mark is formed at predetermined intervals on the track by a spindle motor for rotating a disk recording medium and irradiating the track with laser light. First detection means for detecting a predetermined mark signal related to the predetermined mark based on reflected light from the track; generating means for generating a speed-related signal related to a rotation speed of the spindle motor; Selection means for selecting one of the speed-related signals; rotation speed control means for controlling the rotation speed based on a selection signal from the selection means; the laser beam when a predetermined mark signal is selected by the selection means Determining means for determining the presence or absence of tracking loss, and the tracking loss It occurs, characterized in that it comprises a selection control means for selecting the speed related signal to the selection means when the disk device. 3. The apparatus according to claim 2, further comprising: a second detecting unit that detects a tracking error signal based on the reflected light from the track, wherein the determining unit compares the level of the tracking error signal with a predetermined level to detect the tracking error. 3. The disk device according to claim 2, wherein presence / absence is determined. 4. The disk device according to claim 1, wherein said predetermined mark is a mark embossed on said track.