JP2010113750A - Optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve stable and precise actuator control using a disturbance observer when the use of the disturbance observer can suppress a disturbance caused by the decentration of a disk or a non-periodical disturbance but the use of the disturbance observer unstabilizes the control of a defect signal such as the flaw or defect of the disk and furthermore, an optimal system is not always obtained when simply introducing the disturbance observer to the feedback control system composed of a phase compensator and a low-frequency compensator. <P>SOLUTION: Depending on whether the optical disk device is following a track or is seeking it, the device varies the output of a tracking disturbance observer 22 and the characteristic of a tracking control means, or varies at least the output of a focus disturbance observer 12 or the characteristic of a focus control means. Moreover, in a defect detection period, the outputs of a tracking hold circuit 25 and a focus hold circuit 15 are held. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical disc apparatus.

  An optical disc apparatus records, reproduces, and erases information using an optical disc as a medium. In order to optically record / reproduce information to / from an optical disk using a laser light source, the focus actuator is controlled so that the light spot is positioned on a predetermined reproduction surface, and the light spot is positioned on a predetermined track. It is necessary to control the tracking actuator. In particular, as the recording density increases in recent years and the light spot diameter decreases, the required control accuracy increases.

In a conventional optical disk apparatus, a disturbance observer is introduced as one method for improving control performance against disturbance due to eccentricity of the disk (see Patent Document 1).
JP 2006-48903 A

  By using a disturbance observer, it is possible to suppress disturbances due to eccentricity of the optical disk and aperiodic disturbances. However, the use of a disturbance observer may make the control unstable against defects such as scratches and defects on the disk. Furthermore, in a servo system designed on the assumption that a disturbance observer is applied, optimum servo characteristics may not always be obtained if the disturbance observer function is simply turned off.

  Therefore, an object of the present invention is to realize stable and highly accurate actuator control using a disturbance observer.

  The above object can be achieved by, for example, the configuration described in the claims.

  According to the present invention, stable and highly accurate actuator control using a disturbance observer can be realized.

  Examples of the present invention will be described below.

  The configuration of the optical disk apparatus of this embodiment will be described with reference to FIG.

  In FIG. 1, 1 is an optical disk, 2 is an objective lens, 3 is a focus actuator that moves the objective lens 2 in the focus direction, 4 is a tracking actuator that moves the objective lens 2 in the track direction, 5 is a laser light source, and 6 is light detection. 7 is an optical pickup composed of an objective lens 2, a focus actuator 3, a tracking actuator 4, a laser light source 5, and a light detector 6, 8 is a slider for moving the optical pickup 7 over a wide range in the track direction, and 10 is an optical disk 1. A focus error signal generating means for generating an error signal in the focus direction between the lens and the objective lens 2; 11 a focus control means for controlling the light spot to follow a predetermined reproduction surface; and 12 estimating a disturbance applied to the focus actuator 3 Focus disturbance observer, 13 Vessel, 14 denotes a focus actuator driving means for driving the focus actuator 3.

  20 is a tracking error signal generating means for generating an error in the track direction between the track of the optical disc 1 and the objective lens 2, 21 is a tracking control means for controlling the light spot so as to follow a predetermined track, and 22 is a tracking actuator 4. A tracking disturbance observer for estimating the applied disturbance, 23 is an adder, and 24 is a tracking actuator driving means for driving the tracking actuator 4.

  Reference numeral 30 denotes slider control means for controlling the slider 8, reference numeral 31 denotes slider drive means for driving the slider 8, reference numeral 32 denotes a system controller, reference numeral 35 denotes a spindle motor for rotating the disk, and reference numeral 36 generates a signal corresponding to the rotational speed of the spindle motor. Frequency generating means 37 is motor control means for controlling the spindle motor to rotate at a predetermined speed.

  Next, an outline of the operation of each block and the relationship between the blocks will be described. In FIG. 1, the focus actuator 3 moves the objective lens 2 in the focus direction, and the tracking actuator 4 moves the objective lens 2 in the track direction. The photodetector 6 converts the reflected light into an electrical signal, and sends the converted signal to the focus error signal generation means 10 and the tracking error signal generation means 20.

  The focus error signal generation unit 10 generates a focus error signal from the transmitted signal, and sends the generated focus error signal to the focus control unit 11 and the focus disturbance observer 12. The focus control means 11 sends a control signal for the light spot to follow a predetermined reproduction surface to the adder 13 based on the sent signal. The focus disturbance observer 12 sends a signal for suppressing the focus residual error to the adder 13 based on the signal sent from the focus error signal generating means 10 and the output of the adder 13. The adder 13 adds the sent signals and sends them to the focus actuator driving means 14 and the focus disturbance observer 12. The focus actuator driving means 14 sends a drive signal for moving the focus actuator 3 in the focus direction to the focus actuator 3 based on the sent signal.

  On the other hand, the tracking error signal generation unit 20 generates a tracking error signal from the transmitted signal, and sends the generated tracking error signal to the tracking control unit 21 and the tracking disturbance observer 22. The tracking control means 21 sends a control signal for the light spot to follow a predetermined track to the adder 23 and the slider control means 30 based on the sent signal. The tracking disturbance observer 22 sends a signal for suppressing the tracking residual error to the adder 23 based on the signal sent from the tracking error signal generating means 20 and the output of the adder 23. The adder 23 adds the sent signals and sends them to the tracking actuator driving means 24 and the tracking disturbance observer 22. The tracking actuator driving means 24 sends a driving signal for moving the tracking actuator 4 in the track direction to the tracking actuator 4 based on the sent signal. The slider control means 30 sends a signal for controlling the optical pickup 7 in the track direction to the slider driving means 31 based on the sent signal. Based on the sent signal, the slider driving means 31 sends a signal for driving the optical pickup 7 in the track direction to the slider.

  The spindle motor 35 drives the optical disc 1. The frequency generator 36 converts the rotational speed information of the spindle motor 35 into an electric signal, and sends the converted signal to the motor controller 37. The motor control means 37 controls the spindle motor 35 so that the optical disc 1 rotates at a predetermined rotational speed based on the sent signal.

  The system controller 32 switches the filter characteristics of the focus control means 11 between when the output of the focus disturbance observer 12 is turned on and when it is turned off. Similarly, the tracking control is performed when the output of the tracking disturbance observer 22 is turned on and when it is turned off. The filter characteristic of the means 21 is switched. When the light spot follows a predetermined track, the outputs of the tracking disturbance observer 22 and the focus disturbance observer 12 are set to ON, and the tracking control means 21 and the focus control means 11 are set. During the seek across the track, the output of the tracking disturbance observer 22 is set to OFF and the tracking control means 21 is set. At this time, the settings of the focus disturbance observer 12 and the focus control means 11 are determined depending on the disc and the performance of the apparatus. For example, when the tracking error signal leaks into the focus error signal, the current for driving the focus actuator 3 increases, so that the focus disturbance observer 12 and the tracking disturbance observer 22 are turned off during the seek. Therefore, the control states of the focus disturbance observer 12 and the tracking disturbance observer 22 do not necessarily match.

  The filter characteristic switching of the tracking control means 21 will be described with reference to FIG. The tracking control means 21 has a filter characteristic 100 and a filter characteristic 101 inside as shown in FIG. 2, and switches the filter characteristic by operating an internal switch according to a control signal from the system controller 32. It is assumed that the focus control unit 11 has a similar structure. The filter characteristic switching means may be other than the above. Further, in the tracking system and the focus system, the characteristics that are paired by turning on and off the disturbance observer are not limited to one set. For example, it may have a plurality of pairs of characteristics such as a filter characteristic according to the disk rotation speed and a characteristic suitable when the feedback servo is pulled in.

  Next, operations of the tracking disturbance observer 22 and the tracking control means 21 during the seek across the track will be described with reference to FIG.

In the Seek operation, the system controller 32 outputs a control signal, and the slider control means 30 outputs a control signal for controlling the optical pickup 7 in the track direction with a predetermined drive pattern. Based on this control signal, the slider drive means 31 moves the slider. Is to move. After completion of Seek, the light spot is made to follow a predetermined track. (Hereafter referred to as truck pull-in)
The output state of the tracking disturbance observer 22 during Seek and the filter characteristic switching timing inside the tracking control means 21 will be described with reference to FIG. When the disturbance observer function is ON, it can be expected to suppress disturbance caused by eccentricity of the optical disk or vibration of the optical disk apparatus. However, a phase lag occurs in the low band, which may adversely affect track pull-in after Seek. Therefore, the internal filter characteristics of the tracking control means 21 are changed depending on whether the disturbance observer function is ON or OFF.

  In FIG. 3, the characteristics of the control means at steady state and when the disturbance observer is OFF are steady characteristics 1, the characteristics of the control means at steady state and when the disturbance observer is ON are steady characteristics 2, and the characteristics of the control means at the time of pull-in and when the disturbance observer is OFF. The pull-in characteristic 1 is the pull-in characteristic 2 which is the characteristic of the control means at the pull-in and when the disturbance observer is ON.

  First, as shown by 201 in FIG. 3, the observer function is turned on, the inside of the control means is set to the steady characteristic 2, and a disturbance suppression effect is obtained (201). Next, in order to prepare for the Seek process, the observer function is turned off immediately before the Seek start, the pull-in characteristic 1 is set (202), and the Seek process (203) is performed.

  Next, the period from the start of track pull-in to the completion will be described. After the track pull-in start determination (204), a predetermined time elapse determination (205) is performed, and the observer function is turned ON (206). Here, since the filter characteristic is changed by turning on the observer function, the switching to the stable pull-in characteristic 2 is performed at the same time. Then, a track pull-in completion determination (207) is performed.

  Finally, by returning the filter characteristic to the steady characteristic 2 (208), a series of processing of the Seek operation is completed.

  The output state of the tracking disturbance observer 22 and the switching timing of the filter characteristics may be simultaneously or interchanged.

  Further, the setting of (206) may be the same as (202) depending on the pull-in performance. Further, the setting in (202) may be the same as the setting in (206).

  Here, an example of the disturbance observer used in the present embodiment will be described in detail. FIG. 14 shows details of the tracking disturbance observer 22 used in this embodiment. The tracking disturbance observer 22 passes the signal from the tracking error signal generation means 20 through the first filter characteristic (300) and adds it to the signal from the adder 23. Thereafter, the signal is passed through the second filter characteristic (301) and output to the adder 23.

  When the filter inside the focus disturbance observer 12 or the tracking disturbance observer 22 has a delay buffer memory, the system controller 32 may clear the buffer memory to zero during the seek (FIG. 13 (c)). For example, in the tracking disturbance observer 22, a signal indicating crossing the track appears in the tracking error signal during the seek, and if this value is stored in the buffer memory, the operation immediately after the tracking disturbance observer 22 is turned on is adversely affected. Because there is a possibility of giving. When the filter is composed of an analog circuit, a capacitor constituting the filter may be discharged. Furthermore, the system controller 32 may clear the buffer memory to zero during a predetermined period until the disturbance observer is turned on (see FIG. 13D). For example, in the tracking disturbance observer 22, since the tracking error signal differs depending on whether the disturbance observer is ON or OFF, the buffer memory is cleared to zero until the disturbance observer is turned ON after a predetermined period.

  As described above, by switching the filter characteristics, it is possible to operate the optical disc apparatus that is resistant to disturbance and stable after the seek.

  Example 2 will be described with reference to FIG. Description of the same parts as those in the first embodiment will be omitted, and the operation outline of each block and the relationship between the blocks will be described with respect to the defect detection means 33, the tracking hold circuit 25, and the focus hold circuit 15.

  The defect detection means 33 detects a scratch or a defect on the optical disc 1 as shown in FIG. 5 based on the output signal of the photodetector 6 as a defect, and sends the output signal to the system controller 32. Defect detection is performed based on the RF signal. As shown in FIG. 6, generally, an RF signal is detected as a defect when the signal level decreases while passing the defect and is equal to or lower than Vth. The tracking hold circuit 25 holds the output of the adder 23 based on the outputs of the defect detection means 33 and the system controller 32, and outputs the tracking drive signal shown in FIG. The focus hold circuit 15 also holds the output of the adder 13 based on the outputs of the defect detection means 33 and the system controller 32. Further, the system controller 32 does not necessarily need to operate the tracking hold circuit 25 and the focus hold circuit 15 at the same time. For example, only the tracking hold circuit 25 may be operated.

  When the filter of the focus disturbance observer 12 or the tracking disturbance observer 22 has a delay buffer memory, the system controller 32 clears the buffer memory to zero during the defect detection period (FIG. 12A) based on the defect detection means 33. (FIG. 12 (c)) may be used. Furthermore, the system controller 32 may clear the buffer memory to zero (FIG. 12 (d)) during the defect detection period and for a predetermined period after completion of the defect detection.

  As described above, the outputs of the tracking hold circuit 25 and the focus hold circuit 15 are held during the defect detection, so that the information can be stably reproduced or recorded on the optical disc 1 by preventing the off-track and the off-focus. Can do.

  Claim 5 will be described with reference to FIG. Description of the same parts as those in the second embodiment will be omitted, and the outline of the operation of each block and the relationship between the blocks in the tracking circuit memory 26, the adder 27, the focus circuit memory 16, and the adder 17 will be described.

  The tracking circuit memory 26 stores the tracking drive signal and sends the output to the adder 27. The adder 27 adds the outputs of the tracking hold circuit 25 and the tracking circuit memory 26 and sends it to the tracking actuator drive means 24 as a tracking drive signal. The focus rotation memory 16 stores the focus drive signal and sends the output to the adder 17. The adder 17 adds the outputs of the focus hold circuit 15 and the focus circuit memory 16 and sends the result to the focus actuator drive means 14 as a focus drive signal. The system controller 32 controls the circular memory.

  In Example 2, by using the hold circuit, it was possible to expect an effect of preventing the off-track and out-of-focus at the time of detecting the defect. However, since the voltage level at the time of detecting the defect is held like the tracking drive signal of FIG. 6, the potential difference due to the disk eccentricity occurs immediately after passing the defect, so that the actuator control may become unstable.

  Therefore, the above circulating memory is utilized. Since the operation of the tracking circumference memory 26 and the focus circumference memory 16 is the same, the tracking circumference memory 26 will be described, and the description of the focus circumference memory 16 will be omitted.

  The tracking circuit memory 26 can store an input signal (FIG. 8B) for one rotation of the disk, and is based on the stored waveform before one rotation during the period when the defect detector 33 detects the defect signal. 8 (c) and the adder 27 obtains the tracking drive signal FIG. 8 (d).

  As described above, by using the circular memory, the error signal immediately after passing the defect is reduced from the second embodiment, and a more stable operation of the optical disc apparatus can be expected.

  Further, the tracking hold circuit 25 and the tracking circuit 26 during defect detection may be calculated as shown in FIG. That is, the output of the tracking hold circuit 25 is output as zero as shown in FIG. 9 (a), and the tracking circuit 26 outputs a waveform according to the waveform before one rotation and adds it by the adder 27, thereby adding the waveform shown in FIG. The tracking drive signal as shown in FIG. As described above, the voltage difference immediately after passing the defect is reduced by making a change.

  Example 4 will be described with reference to FIG. A description of the same parts as those in the first embodiment will be omitted, and an outline of the operation of the block of the vibration detection unit 34 will be described.

  The vibration detection means 34 is a means for the optical disk apparatus itself to recognize external vibrations and shocks, and the system controller 32 can recognize that the vibration detection means 34 has detected vibrations. The system controller 32 sets the output of the tracking disturbance observer 22 and the focus disturbance observer 12 to zero output in the normal state, and causes the tracking disturbance observer 22 and the focus disturbance observer 12 when the vibration to the optical disc apparatus itself occurs. Enable the function. Further, when the output states of the tracking disturbance observer 22 and the focus disturbance observer 12 are changed, the settings of the tracking control means 21 and the focus control means 11 are changed simultaneously.

  As described above, when the disturbance observer is used when vibrations occur in the apparatus itself, the tracking control means 21 and the focus control means 11 in the normal state can be easily designed, and a more stable optical disk apparatus. Can be expected.

  Further, as shown in FIG. 11, it has tracking out-of-track detecting means 28 for detecting that the light spot has deviated from the predetermined track, and defocusing detecting means 18 for detecting that the light spot has deviated from the predetermined reproduction surface. When the deviation is detected and the vibration of the optical disk apparatus is detected, the setting of the tracking control means 21 and the tracking disturbance observer 22 is switched, or when the focus is lost and the vibration of the optical disk apparatus is detected, the focus control means 11 And the focus disturbance observer 12 are switched.

  As described above, the filter characteristics of the tracking control means 21 and the focus control means 11 are switched only in the case of vibration that is a direct cause of off-track or out-of-focus, and the tracking disturbance observer 22 and the focus disturbance observer 12 are switched. The setting may be switched.

  Here, the vibration detecting means may be an acceleration sensor and an acceleration detecting means for detecting an acceleration level based on the output of the acceleration sensor.

  Further, instead of the vibration detecting means, the outputs of the focus error signal generating means 10 and the tracking error signal generating means 20 may be band limited, and vibration detection may be performed based on the level of the band limited signal.

Component explanatory drawing of Example 1 Configuration example inside tracking control means Flowchart of disturbance observer and control means setting at Seek Component explanatory drawing of Example 2 Examples of defects (scratches and defects) on optical disks Various waveforms during defect detection 1 Component explanatory drawing of Example 3 Various waveforms during defect detection 2 Various waveforms during defect detection 3 Components Explanation Example 1 of Example 4 Component explanatory diagram of Example 4 Various waveforms during defect detection 4 Various waveforms in Seek Example of tracking disturbance observer 22

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk 2 Objective lens 3 Focus actuator 4 Tracking actuator 5 Laser light source 6 Optical detector 7 Optical pick-up 8 Slider 10 Focus error signal generation means 11 Focus control means 12 Focus disturbance observer 13 Adder 14 Focus actuator drive means 15 Focus hold circuit 16 Focus circuit memory 17 Adder 18 Out-of-focus detection means 20 Tracking error signal generation means 21 Tracking control means 22 Tracking disturbance observer 23 Adder 24 Tracking actuator drive means 25 Tracking hold circuit 26 Tracking circuit memory 27 Adder 28 Tracking loss detection means 30 Slider control means 31 Slider drive means 32 System controller 33 Defect detection Vessel 34 vibration detecting means 35 the spindle motor 36 frequency generating means 37 motor control means

Claims (10)

An optical disk device for reproducing or recording information on an optical disk,
A laser light source for emitting laser light;
An objective lens for condensing the laser beam on the recording surface of the optical disc;
A focus actuator for moving the objective lens in the disc rotation axis direction (focus direction);
A tracking actuator that moves the objective lens in a disc radial direction (track direction);
A photodetector for converting reflected light from the optical disc into an electrical signal;
An optical pickup comprising the laser light source, the objective lens, the focus actuator, the tracking actuator, and the photodetector;
A focus error signal generating means for generating a focus error signal from the output signal of the photodetector;
Tracking error signal generating means for generating a tracking error signal from the output signal of the photodetector;
Focus control means for controlling a light spot to follow a predetermined reproduction surface based on an output signal of the focus error signal generating means;
Tracking control means for controlling the light spot to follow a predetermined track based on the output signal of the tracking error signal generating means;
A focus disturbance observer for estimating a disturbance related to a relative position in the focus direction between the objective lens and the optical disc;
A tracking disturbance observer for estimating a disturbance related to the relative position in the track direction between the objective lens and the optical disc;
An adder 1 for adding the output of the focus control means and the output of the focus disturbance observer;
An adder 2 for adding the output of the tracking control means and the output of the tracking disturbance observer in the previous period;
Focus actuator driving means for driving the focus actuator based on the output signal of the adder 1;
Tracking actuator driving means for driving the tracking actuator based on the output signal of the adder 2;
With a system controller,
The system controller changes the output of the tracking disturbance observer and the characteristics of the tracking control means between the case of following the track and during the seek across the track, or the output of the focus disturbance observer and the characteristics of the focus control means. Do at least one of changing
An optical disc device characterized by the above. The optical disk apparatus according to claim 1,
The system controller sets the value of the filter delay means of the focus disturbance observer and the tracking disturbance observer to zero during the seek, or sets the value of the filter delay means to zero during the seek and a predetermined period after the seek ends. To
An optical disc device characterized by the above. The optical disk apparatus according to claim 1,
A defect detection means for detecting a scratch or a defect of the optical disk based on an output signal of the photodetector;
A focus hold circuit 1 for holding the output of the adder 1 based on the output of the defect detection means and the output of the system controller;
A tracking hold circuit 1 for holding the output of the adder 2 based on the output of the defect detection means and the output of the system controller;
The system controller holds the focus hold circuit 1 and the tracking hold circuit 1 during a period in which a scratch or defect of the optical disk is detected based on the output of the defect detection means.
An optical disc device characterized by the above. An optical disc apparatus according to claim 3, wherein
The system controller sets the values of the delay means of the filters included in the focus disturbance observer and the tracking disturbance observer to zero based on the defect detection means, and sets a predetermined period for the hold release of the focus hold circuit 1 and the tracking hold circuit 1. End delaying the delay means value to zero,
An optical disc device characterized by the above. An optical disc apparatus according to claim 3, wherein
A focus rotation memory for storing an input signal of the focus actuator driving means;
An adder 3 for adding the output signal of the focus circuit memory and the output signal of the focus hold circuit 1;
A tracking circuit memory for storing an input signal of the tracking actuator driving means;
An adder 4 for adding the output signal of the tracking circuit and the output signal of the tracking hold circuit 1;
While the system controller detects a scratch or a defect on the optical disk based on the output of the defect detection means, the system controller outputs an output signal based on signals stored in the focus circuit memory and the tracking circuit memory. Output,
An optical disc device characterized by the above. The optical disk apparatus according to claim 1,
A defect detection means for detecting a scratch or a defect of the optical disk based on an output signal of the photodetector;
A focus hold circuit 2 that holds or zero-outputs the output of the adder 1 based on the output of the defect detection means and the output of the system controller;
A tracking hold circuit 2 for holding or zero-outputting the output of the adder 2 based on the output of the defect detection means and the output of the system controller;
A focus rotation memory for storing an input signal of the focus actuator driving means;
An adder 3 for adding the output signal of the focus circuit memory and the output signal of the focus hold circuit 2;
A tracking circuit memory for storing an input signal of the tracking actuator driving means;
An adder 4 for adding the output signal of the tracking circuit memory and the output signal of the tracking hold circuit 2;
The system controller sets the outputs of the focus hold circuit 2 and the tracking hold circuit 2 to zero output during a period of detecting a scratch or defect on the optical disk based on the output of the defect detection means,
Outputting the signals stored in the focusing circuit memory and the tracking circuit memory;
An optical disc device characterized by the above. An optical disk device for reproducing or recording information on an optical disk,
A laser light source for emitting laser light;
An objective lens for condensing the laser beam on the recording surface of the optical disc;
A focus actuator that moves the objective lens in a focus direction;
A tracking actuator for moving the objective lens in a track direction;
A photodetector for converting reflected light from the optical disc into an electrical signal;
An optical pickup comprising the laser light source, the objective lens, the focus actuator, the tracking actuator, and the photodetector;
A focus error signal generating means for generating a focus error signal from the output signal of the photodetector;
Tracking error signal generating means for generating a tracking error signal from the output signal of the photodetector;
Focus control means for controlling the light spot to follow a predetermined reproduction surface based on the focus error signal;
Tracking control means for controlling the light spot to follow a predetermined track based on the tracking error signal;
A focus disturbance observer for estimating a disturbance related to a relative position in the focus direction between the objective lens and the optical disc;
A tracking disturbance observer for estimating a disturbance related to the relative position in the track direction between the objective lens and the optical disc;
An adder 1 for adding the output of the focus control means and the output of the focus disturbance observer;
An adder 2 for adding the output of the tracking control means and the output of the tracking disturbance observer;
Focus actuator driving means for driving the focus actuator based on the output signal of the adder 1;
Tracking actuator driving means for driving the tracking actuator based on the output signal of the adder 2;
Vibration detecting means for detecting vibration of the optical disc device;
With a system controller,
The system controller changes at least one of the settings of the tracking disturbance observer and the tracking control means, or changes the settings of the focus disturbance observer and the focus control means, based on the output of the vibration detection means. I do,
An optical disc device characterized by the above. The optical disc apparatus according to claim 7, wherein
Off-track detection means for detecting that the light spot has deviated from a predetermined track; and
Out-of-focus detection means for detecting that the light spot is out of the predetermined reproduction surface;
Have
The system controller changes the settings of the tracking disturbance observer and the tracking control means when detecting the out-of-track and the vibration of the apparatus based on the outputs of the out-of-track detecting means, the out-of-focus detecting means and the vibration detecting means. Or, when detecting out-of-focus and detecting vibration of the device, changing the setting of the focus disturbance observer and the focus control means,
An optical disc device characterized by the above. The optical disk device according to claim 7, wherein:
The vibration detection means is an acceleration detection means for detecting an acceleration level based on an acceleration sensor and an output of the acceleration sensor.
An optical disc device characterized by the above. The optical disk device according to claim 7, wherein:
The vibration detection means band-limits the output of the focus error signal generation means, and detects vibration based on the level of the band-limit signal.
An optical disc device characterized by the above.

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