JPH11250563A - Optical disk damping device and optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a damping device capable of damping the vibration of an optical disk by a simple structure when the information signal of the optical disk is recorded/reproduced, and an optical disk device equipped with the same. SOLUTION: This device is provided with a vibration generation control unit 21 for generating a vibration generation control signal based on a focusing error signal from an optical head 13 for irradiating the signal recording surface of an optical disk 11 with a light, and a vibration generation section 22 for generating vibration in the optical disk 11 according to a vibration generation control signal from the vibration generation control unit 21. When vibration occurs in the optical disk 11 during the reproducing of the information signal of the optical disk 11, vibration having an opposite phase is made from the generated vibration and provided to the optical disk 11, and thus the generated vibration is canceled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping device for suppressing vibration of an optical disk when recording and reproducing an information signal of the optical disk, and an optical disk device provided with the vibration damping device.

[0002]

2. Description of the Related Art For example, a so-called compact disc (C
D: registered trademark or magneto-optical disk (MD: registered trademark or M
The reproduction or recording of the information signal on the optical disk such as O) is performed by the optical disk device. For example, an optical disc apparatus for a CD irradiates a light beam from a light source through a driving unit such as a spindle motor for driving the optical disc to rotate and a signal recording surface of the rotating optical disc from a light source through an optical system including an objective lens. Optical head for detecting the return light beam from the optical system by a photodetector via an optical system including an objective lens, and an electromagnetically driven biaxial supporting the objective lens movably in two axial directions, that is, a focusing direction and a tracking direction. It is roughly composed of an actuator.

In such a configuration, a light beam emitted from a light source is focused on a signal recording surface of an optical disk via an optical system. The return light beam from the optical disk is
The light is separated from the light beam emitted from the light source by the optical system and guided to the photodetector. Then, based on the detection signal from the photodetector, the information signal recorded on the optical disc is reproduced. At this time, the spot on the optical disc of the light beam emitted from the light source follows the displacement of the optical disc in a direction orthogonal to the surface direction of the optical disc caused by warpage of the optical disc, etc. The focus of the objective lens is controlled by a two-axis actuator so that the objective lens is focused, and the position of the objective lens in the optical axis direction, that is, the focusing direction is adjusted.

At the same time, the spot on the optical disk of the light beam emitted from the light source follows the displacement of the optical disk in the surface direction of the optical disk caused by the eccentricity of the optical disk or the meandering of the track formed on the optical disk. As described above, the track servo control of the objective lens is performed by the biaxial actuator, and the position in the direction orthogonal to the optical axis of the objective lens, that is, the position in the tracking direction is adjusted.

[0005]

In the above-mentioned optical disk apparatus, during the reproduction of the information signal recorded on the optical disk,
Due to disturbances such as the natural vibration of the optical disk and the sound pressure of the speaker, the optical disk may vibrate significantly. In such a case, the servo control becomes unstable, so that there is a problem that a so-called skipping of sound occurs.

SUMMARY OF THE INVENTION In view of the above, the present invention provides a vibration damping device capable of suppressing vibration of an optical disk when recording and reproducing an information signal of the optical disk with a simple structure, and an optical disk device having the vibration damping device. It is intended to provide.

[0007]

According to the present invention, there is provided a vibration damping device for suppressing vibration of an optical disk,
A vibration generation control unit that generates a vibration generation control signal based on a focusing error signal from an optical head that irradiates light to a signal recording surface of the optical disk; and the optical disk according to a vibration generation control signal from the vibration generation control unit. And a vibration generating unit that generates vibration with respect to the above.

Further, according to the present invention, there is provided a driving means for rotating an optical disk, irradiating light to a signal recording surface of the rotating optical disk, and generating a return light beam from the signal recording surface of the optical disk. An optical disc device comprising: an optical head for detecting, and a control unit that controls the driving unit and the optical head and generates a reproduction signal based on a detection signal from the optical head. A vibration generation control unit configured to generate a vibration generation control signal based on a focusing error signal, and a vibration generation unit configured to generate vibrations on the optical disc in accordance with the vibration generation control signal from the vibration generation control unit. This is achieved by providing a device.

According to the above configuration, when a vibration occurs in the optical disk during the reproduction of the information signal of the optical disk, the vibration generated in the opposite phase is generated from the generated vibration and applied to the optical disk. can do.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the embodiments described below are preferred specific examples of the present invention,
Although various technically preferable limits are given, the scope of the present invention is not limited to these embodiments unless otherwise specified in the following description.

FIG. 1 is a configuration diagram showing an embodiment of an optical disk device provided with an embodiment of a vibration damping device according to the present invention. The optical disk device 10 is an optical disk device for a CD, a spindle motor 12 as a driving unit for rotating the optical disk 11, irradiating a signal recording surface of the rotating optical disk 11 with a light beam, and returning from the signal recording surface. Optical head 1 for reproducing a recording signal by a light beam
3. It is roughly composed of a biaxial actuator 14 for controlling the position of the light beam in two axial directions, that is, a focusing direction and a tracking direction, a control unit 15 for controlling these, a vibration damping device 20 for suppressing the vibration of the optical disk 11, and the like. ing.

As shown in FIG. 2, the optical head 13 has a semiconductor laser element 13a as a light source, a diffraction grating 13b arranged on the optical axis of a light beam from the semiconductor laser element 13a, and a diffraction grating 13b for diffracting the light beam. Laser element 13a
And a beam splitter 13c for reflecting the light beam to the optical disk 11 and transmitting the return light beam from the optical disk 11. Further, the objective lens 1 is arranged on the optical axis of the light beam reflected by the beam splitter 13 c and focuses the reflected light beam on the optical disc 11.
3d, a concave lens 13e disposed on the optical axis of the transmitted light beam in the beam splitter 13c, and condensing the transmitted light beam on the photodetector 13f, and a photodetector detecting the transmitted light beam condensed by the concave lens 13e 13f and the like.

The two-axis actuator 14 includes the optical head 1
3 objective lens 13d in two directions perpendicular to each other, that is, a focusing direction indicated by an arrow Fcs and an arrow Tr
A supporting portion movably supporting in the tracking direction indicated by k and a focusing coil, a tracking coil, a magnet, and the like for moving the objective lens 13d by the electromagnetic force in the above direction are provided.

The control unit 15 includes a signal demodulation circuit 15a for demodulating a recording signal from the optical head 13, a signal demodulation circuit 15
an error correction circuit 15b for correcting the recording signal from
An interface 15c for transmitting a recording signal from the error correction circuit 15b to an external computer or the like is provided. Further, a head access control circuit 15d for moving the optical head 13 to, for example, a predetermined recording track on the optical disk 11 by a track jump or the like, focuses the objective lens 13d held by the biaxial actuator 14 at the moved predetermined position. A servo circuit 15e for moving in the direction Fcs and the tracking direction Trk and an optical disk drive controller 15f for controlling the circuits 15a to 15e and for controlling the drive of the spindle motor 12 at a predetermined number of revolutions are provided.

The vibration damping device 20 includes a vibration generation control circuit 21 for generating a vibration generation control signal based on a focus error signal from the optical head 13, and a vibration generation control circuit 21.
A vibration generating device 22 that generates vibrations on the optical disk 11 in accordance with a vibration generation control signal from the optical disk 11. As shown in FIG. 3, the vibration generation control circuit 21 extracts a vibration waveform from the focus error signal from the optical head 13 and a phase inversion that inverts the phase of the vibration waveform from the vibration waveform extraction unit 21a. The circuit 21b is provided.

The vibration generator 22 includes a phase inversion circuit 21b.
An amplifier 22a for amplifying an inverted signal from the optical disk 11 and a predetermined distance on the surface opposite to the signal recording surface of the optical disk 11, and generate a sound pressure in accordance with the amplified signal from the amplifier 22a to be opposite to the signal recording surface. The speaker 22b that applies vibration to the side surface is provided. The vibration generator 2
The speaker 2 is not limited to the speaker 22b as long as it can generate vibration, and may be a vibration generating device that generates vibration by, for example, atmospheric pressure. The vibration generator 22 may be disposed on the signal recording surface side as long as vibration can be applied to the surface of the optical disk 11.

An operation example of such a configuration will be described. The optical disk drive controller 15f controls the drive of the spindle motor 12 at a predetermined number of rotations to rotate the optical disk 11. Then, the head access control circuit 15d drives the semiconductor laser element 13a to emit a light beam, and moves the optical head 13 to, for example, the optical disk 1
1 is moved to a predetermined track on the signal recording surface by track jump or the like. That is, the semiconductor laser element 13a
Is emitted by the diffraction grating 13b.
The light is separated into at least three light beams of the first-order diffracted light and the ± first-order diffracted light, and is guided to the beam splitter 13c. These diffracted light beams are polarized by 90 ° and reflected by the beam splitter 13c, and guided to the objective lens 13d. These reflected light beams are transmitted to the objective lens 13d.
The light is focused on a predetermined track on the signal recording surface of the optical disc 11 rotating via the optical disc 11.

At this time, a spot of the light beam emitted from the semiconductor laser element 13a on the optical disk 11 is generated by warpage of the optical disk 11 or the like.
The objective lens 13d is subjected to focus servo control by the biaxial actuator 14 so as to follow the displacement of the optical disk 11 in a direction perpendicular to the surface direction of the optical disk 11 and to focus on a predetermined track on the signal recording surface of the optical disk 11. Thus, the optical axis direction of the objective lens 13d, that is, the focusing direction Fc
The position of s is adjusted. At the same time, the semiconductor laser device 13
The spot on the optical disk 11 of the light beam emitted from the optical disk 11 follows the displacement of the optical disk 11 in the surface direction of the optical disk 11 caused by the eccentricity of the optical disk 11, the meandering of the track formed on the optical disk 11, and the like. As described above, the track servo control of the objective lens 13d is performed by the biaxial actuator 14, and the position in the direction orthogonal to the optical axis of the objective lens 13d, that is, the position in the tracking direction Trk is adjusted.

That is, the servo circuit 15 e
By controlling the driving current to the focusing coil and the tracking coil of the biaxial actuator 14 based on the focusing error signal and the tracking error signal among the detection signals from the f, magnetic flux is generated in the focusing coil and the tracking coil. Occurs.
Then, due to the interaction between the magnetic flux generated from the coil and the magnetic flux generated by the magnet, a driving force is generated in the magnet in the focusing direction Fcs and the tracking direction Trk, respectively, and the objective lens 13d is driven in the focusing direction Fcs and the tracking direction Trk. be able to.

The return light beam from the optical disk 11 is guided again to the beam splitter 13c via the objective lens 13d. When these return light beams pass through the beam splitter 13c, astigmatism for focus detection occurs, and is guided to the concave lens 13e. These return light beams are guided to the photodetector 13f via the concave lens 13e. Then, a recording signal among the detection signals from the photodetector 13f is input to the signal demodulation circuit 15a. The signal demodulation circuit 15a demodulates the recording signal from the photodetector 13f and inputs the demodulated signal to the error correction circuit 15b. Error correction circuit 15b
Corrects the error of the demodulated signal from the signal demodulation circuit 15a,
The data is sent to an external computer or the like via the interface 15c. Thus, the information signal recorded on the optical disk 11 is reproduced by an external computer or the like.

During reproduction of this information signal, the optical disk 11
If the optical disk 11 vibrates greatly due to the natural vibration of the optical disk or disturbance such as the sound pressure of the speaker, the vibration generation control circuit 21
The vibration waveform extraction unit 21a extracts a vibration waveform from the focusing error signal among the detection signals from the photodetector 13f and inputs the vibration waveform to the phase inversion circuit 21b. The focusing error signal at this time is, for example, si
The waveform has an n-curve. Among these waveforms, a large wave is a vibration waveform of the optical disk 11, and a small wave riding on the vibration waveform is a noise waveform of the photodetector 13f.

The phase inversion circuit 21b includes a vibration waveform extraction unit 2
The phase of the vibration waveform from 1a is inverted and transmitted to the speaker 22a via the amplifier 22a of the vibration generator 22. The speaker 22a generates a sound pressure according to the inversion signal from the phase inversion circuit 21b, and gives a vibration to the surface of the optical disk 11 opposite to the signal recording surface. This allows
Since the vibration of the optical disk 11 is offset, the optical disk 1
1 comes to rotate stably. Then, since the servo control is stabilized, so-called skipping of sound or the like can be prevented, and the information signal recorded on the optical disc 11 can be reproduced stably.

In the above embodiment, a compact disk (CD) is described as an example of an optical disk, but the present invention can be applied to other optical disks such as a magneto-optical disk (MD or MO) or a phase change disk. Further, the present invention can be applied to any device that can extract a focusing error signal.

[0024]

As described above, according to the present invention, the vibration of the optical disk when recording and reproducing the information signal of the optical disk can be suppressed with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of an optical disk device including an embodiment of a vibration damping device according to the present invention.

FIG. 2 is a schematic diagram showing a configuration of an optical head in the optical disk device of FIG.

FIG. 3 is a configuration diagram showing an embodiment of a vibration damping device according to the present invention.

FIG. 4 is a waveform chart showing an example of a focus error signal from the optical head of FIG. 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Optical disk apparatus, 11 ... Optical disk apparatus, 12 ... Spindle motor, 13 ... Optical head, 13a ... Semiconductor laser element, 13b ... Diffraction grating, 13c ... Beam splitter, 13d: objective lens, 13e: concave lens, 13f: photodetector, 14: two-axis actuator, 15: control unit, 15a: signal demodulation circuit, 15b: error correction Circuit, 15c: interface, 15d: head access control circuit, 15e: servo circuit, 15
f optical disk controller, 20 vibration damping device, 21 vibration generation control circuit, 21a vibration waveform extraction unit, 21b phase inversion circuit, 22 vibration generation device, 22a ... Amplifier, 22b ... Speaker

Claims (6)

[Claims] 1. A vibration damping device for suppressing vibration of an optical disk, wherein the vibration generation control generates a vibration generation control signal based on a focusing error signal from an optical head that irradiates a signal recording surface of the optical disk with light. According to a vibration generation control signal from the vibration generation control unit,
A vibration damping device, comprising: a vibration generator that generates vibration with respect to the optical disk. 2. The vibration generation control unit includes: a vibration waveform extraction unit that extracts a vibration waveform from the focusing error signal; and a phase inversion unit that inverts the phase of the vibration waveform from the vibration waveform extraction unit. Item 2. The vibration damping device according to Item 1. 3. The apparatus according to claim 1, wherein the vibration generator includes an amplifier that amplifies the inverted signal from the phase inverter, and a speaker that generates a sound pressure according to the amplified signal from the amplifier. Damping device. 4. An optical head for rotating and driving an optical disc, irradiating a signal recording surface of the rotating optical disc with light, and detecting a return light beam from the signal recording surface of the optical disc; A control unit for controlling an optical head and generating a reproduction signal based on a detection signal from the optical head, wherein a vibration generation control is performed based on a focusing error signal from the optical head. A vibration generation control unit that generates a signal,
According to a vibration generation control signal from the vibration generation control unit,
An optical disc device, comprising: a vibration damping device having a vibration generating unit that generates vibration with respect to the optical disc. 5. The vibration generation control unit includes: a vibration waveform extraction unit that extracts a vibration waveform from the focusing error signal; and a phase inversion unit that inverts the phase of the vibration waveform from the vibration waveform extraction unit. Item 5. An optical disk device according to item 4. 6. The apparatus according to claim 4, wherein the vibration generator includes an amplifier for amplifying an inverted signal from the phase inverter, and a speaker for generating a sound pressure in accordance with the amplified signal from the amplifier. Optical disk device.