OPTICAL DISC DRIVE AND METHOD OF CONTROLLING ACTUATOR

Abstract

The present invention comprises a tracking actuator which drives an objective of a pickup emitting the laser beam, in accordance with a drive signal, a detector which detects or estimates a temperature variation putting an influence on a sensitivity of the tracking actuator, and a corrector which corrects the drive signal in accordance with information detected or estimated by a state detector.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.

FIG. 1 is an illustration showing a notebook-type personal computer equipped with an optical disc drive according to an embodiment of the present invention;

FIG. 2 is an illustration showing an outer appearance of the optical disc drive according to the embodiment of the present invention;

FIG. 3 is an illustration showing a state in which a drawer is ejected from the optical disc drive shown in FIG. 2;

FIG. 4 is a block diagram showing an entire configuration of the optical disc drive according to the embodiment of the present invention;

FIG. 5 is a block diagram showing main components of the optical disc drive according to the embodiment of the present invention;

FIG. 6 is an illustration showing a drive voltage of a focus actuator and a relationship in distance between the optical disc and an objective;

FIG. 7 is an illustration showing a principle of driving the focus actuator;

FIG. 8 is an illustration showing measurement of displacement of the tracking actuator in a case where a voltage is applied to the focus actuator;

FIG. 9 is an illustration showing measurement of influences of resistance variation in a case where a voltage is applied to the focus actuator;

FIG. 10 is an illustration showing a circuit of correcting the sensitivity of the tracking actuator according to the embodiment of the present invention;

FIG. 11 is an illustration showing a circuit of correcting the sensitivity of the tracking actuator according to another embodiment of the present invention; and

FIG. 12 is an illustration showing a circuit of correcting the sensitivity of the tracking actuator according to the other embodiment of the present invention.

Claims

1. An optical disc drive, for emitting a laser beam on a label surface of an optical disc and recording picture information thereon, comprising: an actuator which drives an objective lens of a optical pickup emitting the laser beam, in accordance with a drive signal;a detector which detects a temperature variation putting an influence on a sensitivity of the actuator on the drive signal;anda corrector which corrects the drive signal in accordance with information detected by the detector.

2. The optical disc drive according to claim 1, wherein the actuator is a tracking actuator and the detector estimates the temperature variation in accordance with the drive signal of the focus actuator driving the objective lens.

3. The optical disc drive according to claim 1, wherein the actuator is a tracking actuator and the detector detects the temperature variation by a temperature detection element.

4. The optical disc drive according to claim 1, wherein the actuator is a tracking actuator and the detector estimates the temperature variation by measuring a coil resistance of the tracking actuator.

5. A method of controlling an actuator of an optical disc drive for emitting a laser beam on a label surface of an optical disc and recording picture information thereon, the method comprising: moving an objective lens of a optical pickup emitting the laser beam in a radial direction of the optical disc, by a tracking actuator, in accordance with a drive signal;detecting a temperature variation putting an influence on a sensitivity of the tracking actuator on the drive signal;andcorrecting the drive signal in accordance with the detected temperature variation information.

6. The method according to claim 5, wherein in the detection or estimation of the temperature variation, the temperature variation is estimated in accordance with the drive signal of the focus actuator driving the objective lens.

7. The method according to claim 5, wherein in the detection or estimation of the temperature variation, the temperature variation is estimated by a temperature detection element.

8. The method according to claim 5, wherein in the detection or estimation of the temperature variation, the temperature variation is estimated by measuring a coil resistance of the tracking actuator.

9. An optical disc drive, for emitting a laser beam from an optical pickup on a label surface of an optical disc and recording picture information thereon, comprising: a focus actuator which moves an objective lens in the optical pickup in a focus direction;a tracking actuator which moves the objective lens in the optical pickup in a radial direction;a drive signal generator which receives a reflection detecting signal from the optical pickup and generates a focus drive signal of the focus actuator and a tracking drive signal of the tracking actuator; andan amplifier which, upon recording the picture information, corrects an amplification width of the tracking drive signal in accordance with a signal of comparison between a low frequency signal generated from the focus drive signal and a predetermined reference voltage and supplies a drive signal to a tracking coil of the tracking actuator.

10. An optical disc drive, for emitting a laser beam from an optical pickup on a label surface of an optical disc and recording picture information thereon, comprising: a focus actuator which moves an objective lens in the optical pickup in a focus direction;a tracking actuator which moves the objective lens in the optical pickup in a radial direction;a drive signal generator which receives a reflection detecting signal from the optical pickup and generates a focus drive signal of the focus actuator and a tracking drive signal of the tracking actuator;a thermistor which detects a temperature of a tracking coil of the tracking actuator driven in accordance with the tracking drive signal; andan amplifier which, upon recording the picture information, corrects an amplification width of the tracking drive signal in accordance with a signal of comparison between a voltage output in accordance with the temperature detected by the thermistor and a predetermined reference voltage and supplies a drive signal to the tracking coil.

11. An optical disc drive, for emitting a laser beam from an optical pickup on a label surface of an optical disc and recording picture information thereon, comprising: a focus actuator which moves an objective lens in the optical pickup in a focus direction;a tracking actuator which moves the objective lens in the optical pickup in a radial direction;a drive signal generator which receives a reflection detecting signal from the optical pickup and generates a focus drive signal of the focus actuator and a tracking drive signal of the tracking actuator;a tracking coil of the tracking actuator driven by a drive voltage obtained by adding an AC signal to the tracking drive signal;a resistor which obtains an output voltage of the tracking coil; andan amplifier which, upon recording the picture information, corrects an amplification width with a signal obtained by subtracting a high frequency component of the output voltage from a high frequency component of the drive voltage and supplies the drive signal to the tracking coil.