JP2005259248A - Optical disk recording and reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk recording and reproducing device in which, even when the reproducing of information or the recording of information is performed to an optical disk suffering from surface wobbling, or warpage, or eccentricity, an optical pickup can be made to follow quickly to tracks of the optical disk. <P>SOLUTION: In order to investigate the shape of an optical disk on which the reproducing of information or the recording of information is desired to be performed, a system controller 22 sets a shape acquiring point to the optical disk 1 by lowering the revolving speed of a spindle motor 2 to a prescribed revolving speed while controlling a servo control part 4 and then moves an optical pickup 2 to the shape acquiring point and calculates the shape value of the pertinent optical disk 2 on the basis of the value of a servo control voltage at this time. At the time of reproduction or recording, the controller 22 adds the shape calculated value to the value of the servo control voltage and it controls the servo control part 4 so that a servo control voltage by the value of the servo control voltage to which the shape calculated value is added is output by the servo control part 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to an optical disk recording / reproducing apparatus that records information on an optical disk or reproduces information recorded on an optical disk, and more particularly to an optical disk recording / reproducing apparatus having a function of controlling an optical pickup in accordance with the shape of the optical disk.

In general, in an optical disk recording / reproducing apparatus, when the optical disk is rotated during reproduction, laser light is irradiated along the track of the optical disk, and the recorded information on the track is read by the reflected light. The servo control unit performs tracking servo control for appropriately shifting the laser light irradiation position in the radial direction of the optical disc so that the laser light irradiation position coincides with the track position. This tracking servo control is realized by supplying a tracking servo control voltage from the servo control unit to a tracking actuator that holds the optical pickup in a movable state, thereby moving the optical pickup appropriately in the radial direction of the optical disk.

By the way, in the conventional optical disk recording / reproducing apparatus, when the optical disk is mounted on the mounting portion and the recorded information of the optical disk is reproduced by rotating the optical disk, the output of the optical pickup is detected when there is surface deflection, warpage or eccentricity of the optical disk. Surface deviation, warpage, or eccentricity of the optical disc is detected by a focus error signal or tracking error signal extracted from the RF signal that is a signal.
JP 2002-123957 A Japanese Patent Laid-Open No. 11-16171 JP 2003-196849 A JP 2000-276753 A

However, in such a conventional optical disc recording / reproducing apparatus, the shape of the optical disc is not confirmed at all, or even if the shape is confirmed, the shape is confirmed by performing shape recognition at one point on the optical disc, and Since the rotational speed of the optical disk is not reduced when this shape is confirmed, the servo system can no longer cope with surface deflection, warpage, or eccentricity of the optical disk that originally exceeds the servo control range. May not be able to follow the track of the optical disc. Therefore, when playback or recording is performed on an optical disc with surface deflection, warpage, or eccentricity that the servo system cannot handle, playback or recording temporarily stops during playback or recording, and playback or recording thereafter becomes impossible. May end up.

In the prior art of Patent Document 1, a focus error signal and a tracking error signal are acquired in two stages of low speed and high speed, and the power supply voltage of each control driver is increased from the difference in deviation between these error signals. However, this does not change the initial value of the servo control voltage, it simply multiplies the servo control voltage, and not only low speed but also high-speed shape acquisition is required. End up. In addition, since the servo control voltage is increased uniformly, the resolution of control is lowered and it becomes difficult to perform delicate control. In addition, since the resolution of the control is lowered, there is a possibility that writing errors increase during recording, and this servo control is not suitable for the recording process.

In the prior art of Patent Document 2, for example, in a focus servo system, focus adjustment is performed based on a bias value set based on a control signal, and the control circuit adds to the focal position according to the state of the optical disk. Alternatively, negative bias voltage data is generated and applied to the focus servo system as a control signal, and a bias point at which the jitter of the reproduction signal is minimized is detected and fixed at a bias value at which the jitter is minimized. Although surface wobbling, warping, and eccentricity are dealt with, this processing is performed during reproduction, so it is impossible to deal with surface wobbling, warping, or eccentricity of the optical disk that originally exceeds the servo control range.

In the prior art of Patent Document 3, when tracking pull-in is performed, the relative speed between the moving speed of the optical disk to be pulled in the track direction and the moving speed of the optical pickup is detected, and the tracking actuator is used in accordance with the detected relative speed. By controlling the polarity and voltage value of the actuator drive voltage to be supplied, we deal with surface wobbling, warping or eccentricity of the optical disc, but this processing is performed during playback, so it originally exceeds the servo control range. It cannot cope with surface deflection, warpage or eccentricity of an optical disk.

In the prior art of Patent Document 4, vibration information generated by the rotation of the disk is detected and stored in a memory, and each of the focus direction and the tracking direction to the objective lens in the optical pickup is based on the stored vibration information. By generating a correction signal for removing the predicted vibration effect and generating an actuator drive signal that is added to the servo control signal, it is possible to reduce the surface deflection, warpage, or eccentricity of the optical disc. Although this is being dealt with, since this processing is performed during playback, it is impossible to deal with surface deflection, warpage, or eccentricity of the optical disc that originally exceeds the servo control range.

The present invention has been made in order to solve the above-described problems. Even when reproduction or recording is performed on an optical disc having surface wobbling, warping, or eccentricity, the optical pickup is adapted to the track of the optical disc. An object of the present invention is to provide an optical disc recording / reproducing apparatus that can quickly follow.

In order to achieve the above object, the invention of claim 1 includes an optical pickup for optically reproducing / recording information on an optical disc, and a thread for moving the optical pickup in the radial direction of the optical disc, Focus control and tracking control for driving the spindle motor and the sled according to instructions from the system controller and moving the focal position of the laser light emitted from the optical pickup in the vertical and horizontal directions with respect to the recording surface of the optical disc, respectively. In the optical disk recording / reproducing apparatus having a servo control unit for performing the above-described optical pickup, the system controller controls the servo control unit to check in advance the shape of the optical disk to be reproduced or recorded. The rotational speed of the spindle motor A rotational speed reducing means for reducing the rotational speed to a rotational speed, a shape acquisition point setting means for setting a shape acquisition point for the optical disk in order to examine the shape of the optical disk, and a shape acquisition point for controlling the servo control unit Shape acquisition point moving means for moving to the shape acquisition means, storage processing means for storing in the memory the value of the servo control voltage based on the output signal of the optical pickup obtained by moving to the shape acquisition point and rotating the optical disc by a predetermined amount, After the servo control voltage values corresponding to the number of shape acquisition points are stored in the memory, the shape value of the optical disk is calculated based on a plurality of servo control voltage values stored in the memory and stored in the memory And a shape value calculation means for reading the shape calculation value stored in the memory at the time of reproduction or recording. Adding means for adding to the value of the control voltage; and servo control means for controlling the servo control unit so that a servo control voltage based on the value of the servo control voltage added with the shape calculation value is output from the servo control unit; There is provided an optical disc recording / reproducing apparatus characterized by comprising:

In this configuration, in order to investigate in advance the shape of the optical disc to be reproduced or recorded, the rotation speed reduction means of the system controller controls the servo control unit to reduce the rotation speed of the spindle motor to a predetermined rotation speed. The shape acquisition point for the optical disc is set by the shape acquisition point setting means, and the shape acquisition point moving means controls the servo control unit to move the optical pickup to the shape acquisition point. Then, the value of the servo control voltage based on the output signal of the optical pickup obtained by moving to the shape acquisition point and rotating the optical disk by a predetermined rotation is stored in the memory by the storage processing means. After the servo control voltage values corresponding to the number of shape acquisition points are stored in the memory in this way, the disk shape value calculation means calculates the shape value of the optical disk based on the values of the plurality of servo control voltages stored in the memory. Calculate

At the time of reproduction or recording, the adding means reads the shape calculation value stored in the memory,
The servo control means controls the servo control unit so that a servo control voltage based on the servo control voltage value added with the shape calculation value is output from the servo control unit. Thereby, since the servo control unit outputs a servo control voltage based on the value of the servo control voltage to which the calculated shape value is added, even if the optical disc being reproduced or recorded has surface deflection, warpage, or eccentricity, The optical pickup can quickly follow the track on the optical disk.

According to this configuration, the servo control unit outputs a servo control voltage based on the value of the servo control voltage added with the calculated value of the optical disk shape, so that reproduction or recording is performed on an optical disk having surface wobbling, warping, or eccentricity. Even when the optical pickup is performed, the optical pickup can quickly follow the track of the optical disk, so that errors during reproduction or recording are almost eliminated, and smooth reproduction processing or recording processing can be performed without interruption.

The invention of claim 2 is an optical pickup for optically reproducing / recording information on an optical disc, a thread for moving the optical pickup in the radial direction of the optical disc,
Focus control and tracking control for driving the spindle motor and the sled according to instructions from the system controller and moving the focal position of the laser light emitted from the optical pickup in the vertical and horizontal directions with respect to the recording surface of the optical disc, respectively. In the optical disk recording / reproducing apparatus having a servo control unit for performing the above-described operation on the optical pickup, the system controller sets a predetermined number of rotations of the spindle motor in order to examine in advance the shape of the optical disk to be reproduced or recorded. Decrease the number of revolutions, set the shape acquisition point for the optical disc, move to the shape acquisition point and rotate the optical disc for a predetermined rotation, based on the value of the servo control voltage based on the output signal of the optical pickup Calculate shape value During reproduction or recording, the shape calculation value is added to the servo control voltage value, and the servo control unit is controlled so that the servo control voltage with the shape calculation value added is output from the servo control unit. An optical disc recording / reproducing apparatus is provided.

In this configuration, the system controller performs the following process in order to examine in advance the shape of the optical disc to be reproduced or recorded. That is, the servo control unit is controlled to reduce the rotational speed of the spindle motor to a predetermined rotational speed, and the shape acquisition point for the optical disc is set. Then, the optical pickup is moved to the shape acquisition point, and the shape value of the optical disk is calculated based on the value of the servo control voltage obtained from the output signal of the optical pickup at this time.

During reproduction or recording, the servo control unit adds the shape calculation value to the servo control voltage value and outputs a servo control voltage based on the servo control voltage value to which the shape calculation value is added from the servo control unit. To control. Thereby, since the servo control unit outputs a servo control voltage based on the value of the servo control voltage to which the calculated shape value is added, even if the optical disc being reproduced or recorded has surface deflection, warpage, or eccentricity, The optical pickup can quickly follow the track on the optical disk.

According to this configuration, the servo control unit outputs a servo control voltage based on the value of the servo control voltage added with the calculated value of the optical disk shape, so that reproduction or recording is performed on an optical disk having surface wobbling, warping, or eccentricity. Even when the optical pickup is performed, the optical pickup can quickly follow the track of the optical disk, and therefore, errors during reproduction or recording are almost eliminated, and smooth reproduction processing or recording processing can be performed without interruption.

According to a third aspect of the present invention, in the second aspect of the invention, the system controller controls the servo control unit to control the rotation speed of the spindle motor in order to investigate in advance the shape of the optical disk to be reproduced or recorded. Rotational speed reduction means for reducing the rotational speed to a predetermined rotational speed, shape acquisition point setting means for setting a shape acquisition point for the optical disk in order to examine the shape of the optical disk, and shape acquisition of the optical pickup by controlling the servo control unit Shape acquisition point moving means for moving to a point; storage processing means for storing in a memory a value of a servo control voltage based on an output signal of an optical pickup obtained by moving to the shape acquisition point and rotating an optical disk by a predetermined rotation; and After the servo control voltage values for the number of shape acquisition points are stored in the memory,
Since it has disk shape value calculation means for calculating the shape value of the optical disk based on a plurality of servo control voltages stored in the memory and storing it in the memory, it is possible to obtain a shape calculation value indicating the shape of the optical disk. A servo control voltage having a quick response can be obtained by using the calculated shape value.

According to a fourth aspect of the invention, in the third aspect of the invention, the system controller reads the calculated shape value stored in the memory and adds it to the servo control voltage value during reproduction or recording, and the shape Servo control means for controlling the servo control unit so that a servo control voltage based on the value of the servo control voltage to which the calculated value is added is output from the servo control unit. Servo control voltage can be output according to the value of the servo control voltage added to the optical pickup. Even when playback or recording is performed on an optical disc with surface deflection, warpage, or eccentricity, the optical pickup is applied to the track of the optical disc. Can be followed quickly.

As described above, according to the present invention, the system controller controls the servo control unit to reduce the rotational speed of the spindle motor to a predetermined rotational speed in order to check the shape of the optical disk to be reproduced or recorded in advance. Number acquisition means, shape acquisition point setting means for setting a shape acquisition point for the optical disk to investigate the shape of the optical disk, and shape acquisition point movement for controlling the servo control unit to move the optical pickup to the shape acquisition point Means, storage processing means for storing in a memory a servo control voltage value based on an output signal of an optical pickup obtained by moving to the shape acquisition point and rotating the optical disk by a predetermined rotation, and servo control voltages for the number of shape acquisition points Is stored in the memory, and then based on a plurality of servo control voltage values stored in the memory. A disk shape value calculating means for calculating a disk shape value and storing it in the memory, and an addition means for reading the shape calculated value stored in the memory and adding it to the value of the servo control voltage during reproduction or recording And servo control means for controlling the servo control unit so that a servo control voltage based on the value of the servo control voltage added with the shape calculation value is output from the servo control unit. Servo control voltage can be output based on the servo control voltage value added with the calculated value of the shape of the optical pickup, so that even if playback or recording is performed on an optical disc with surface wobbling, warping, or eccentricity, the optical pickup Can be made to follow the track of the optical disc quickly. Scan is almost no, it is possible to perform smooth playback processing or recording processing without interruption.

Further, according to the present invention, the system controller reduces the number of revolutions of the spindle motor to a predetermined number of revolutions and sets a shape acquisition point for the optical disc in order to examine in advance the shape of the optical disc to be reproduced or recorded. The shape value of the optical disk is calculated based on the value of the servo control voltage based on the output signal of the optical pickup obtained by moving the optical disk to a predetermined rotation by moving to the shape acquisition point. Is added to the value of the servo control voltage, and the servo control unit is controlled so that the servo control voltage to which the calculated shape value is added is output from the servo control unit. Servo control voltage can be output based on the added servo control voltage value.
As a result, even when reproduction or recording is performed on an optical disc having surface wobbling, warping, or eccentricity, the optical pickup can quickly follow the track of the optical disc. Therefore, smooth reproduction processing or recording processing can be performed without interruption.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram showing a configuration of an optical disc recording / reproducing apparatus according to an embodiment of the present invention.

The optical disk recording / reproducing apparatus includes a spindle motor 5 that rotates the optical disk 1, an optical pickup 2 that emits a laser beam for reproducing information recorded on the optical disk 1 and receives reflected light from the optical disk 1, and A sled 3 for moving the optical pickup 2 in the radial direction of the optical disc 1, and a spindle motor 5 and the sled 3 are driven according to an instruction from the system controller 22 and an objective lens (not shown) built in the optical pickup 2 And a servo control unit 4 that performs control to move the focal position of the laser beam in the vertical direction and the horizontal direction with respect to the recording surface of the optical disc 1.

The optical disc recording / reproducing apparatus also amplifies an RF signal which is a read signal from the optical pickup 2 during reproduction of the optical disc 1 and converts the RF signal output from the RF amplifier 6 into digital data. A digital signal processing unit 8 that stores data generated by performing signal demodulation processing and error correction processing according to the data format of the optical disc 1 in the RAM 7, and is output from the digital signal processing unit 8 in response to an instruction from the system controller 22. A stream separation unit 9 is provided for separating audio data, sub-picture data, and video data from the data stream.

The optical disc recording / reproducing apparatus also receives an audio decoder 11 that receives the audio data output from the stream separation unit 9 and performs a predetermined decoding process, and temporarily stores the data to perform the decoding process in the audio decoder 11. The RAM 10 to be stored in the sub-picture decoder 13, the sub-picture decoder 13 that inputs the sub-picture data output from the stream separation unit 9 and performs a predetermined decoding process, and the sub-picture decoder 13 temporarily stores the data to perform the decoding process. The RAM 12 to be stored in the video decoder 15, the video decoder 15 that receives the video data output from the stream separator 9 and performs a predetermined decoding process, and temporarily stores the data for the decoding process in the video decoder 15. RAM 14 is provided.

The optical disk recording / reproducing apparatus also synthesizes the data output from the video decoder 15 and the data output from the sub-picture decoder 13 in accordance with an instruction from the system controller 22, and outputs from the video processor 17. The synthesized data is converted into a video signal for display and a video encoder 18 that displays an image on the display device 20, and the data output from the audio decoder 11 is converted into an analog audio signal and supplied to, for example, a speaker 19. And a D / A converter 16.

The optical disc recording / reproducing apparatus includes an operation unit 21 having various operation keys such as a reproduction key for giving a reproduction instruction to the system controller 22 and a stop key for instructing a reproduction stop, and the entire apparatus. And the system controller 22 to be controlled.
The operation unit 21 may be a remote controller or an operation unit provided on the operation panel of the apparatus main body.

In addition, this optical disk recording / reproducing apparatus performs a calculation process according to the flash ROM 23 storing a program and data for controlling each component of the apparatus and controlling the entire apparatus, and the program and data of the flash ROM 23. System controller 2
2 and a RAM 27 as a memory for storing a servo control voltage value and a shape calculation value, which will be described later.

The optical disc recording / reproducing apparatus also includes a recording data modulation circuit 25 that modulates video / audio data sent from a television receiver (not shown), a personal computer, or the like to the optical disc 1, and the recording data modulation circuit. And a laser modulation circuit 26 that outputs to the optical pickup 2 a laser modulation signal for modulating the laser light emitted from the optical pickup 2 based on the modulation data modulated by 25.

The system controller 22 controls the servo control unit 4 to reduce the rotational speed of the spindle motor 5 to a predetermined rotational speed in order to investigate in advance the shape of the optical disk 1 to be reproduced or recorded, which is a feature of this embodiment. A rotational speed lowering means 221 for controlling the shape, and a shape acquisition point setting means 222 for setting a shape acquisition point for the optical disc 1 in order to investigate the shape of the optical disc 1; Shape acquisition point moving means 223 for moving to the shape acquisition means, storage processing means 224 for storing the value of the servo control voltage obtained from the output signal of the optical pickup 2 moved to the shape acquisition point in the RAM 27, and the number of the shape acquisition points After the servo control voltage values are stored in the RAM 27, the servo control voltage values are stored in the RAM 27 based on a plurality of servo control voltage values. Which has a disk shape value calculation unit 225 to be stored in the RAM27 to calculate the shape value of the optical disc 1 have, at the time of reproduction or recording, R
An adder 226 that reads the calculated shape value stored in the AM 27 and adds it to the servo control voltage value, and a servo control voltage based on the servo control voltage value added with the calculated shape value is output from the servo control unit 4. Servo control means 227 for controlling the servo control unit 4 as described above.

Here, the calculation method of the said shape calculation value is demonstrated with reference to FIGS. FIG. 2 shows the positions of the shape acquisition points P1, P2, and P3 on the optical disc 1. FIG. 3 shows a state in which the optical disc 1 has caused surface deflection, and FIG. 4 shows a state in which the optical disc 1 has caused surface deflection and warpage.

As shown in FIG. 3, when the optical disc 1 is tilted (surface runout) with respect to the axis of the spindle motor 5, the optical disc 1 has an inclination angle with respect to the reference line L, and the shape acquisition point P1.
, P2, P3 to the reference line L have distances H1, H2, H3, and when the optical disk 1 is not warped, H1 / a = H2 / b = H3 / c. Then, as shown in FIG. 4, when the optical disc 1 has surface deflection and warpage, Y1 / a ≠ Y2 / b ≠ Y3 / c. When the optical pickup 2 reads the shape acquisition points P1, P2, and P3 on the optical disc 1, since the distance H1 <distance H2 <distance H3, the shape reading voltage by the optical pickup 2 is the shape acquisition points P1, P2, and P3, respectively. Differently, each shape reading voltage value is calculated as each shape calculation value RA.
Store in M27.

3 and 4, for convenience of explanation, the shape reading voltage has been described on the assumption that the optical pickup 2 has read the shape acquisition points P1, P2, and P3 while the optical disk 1 is stopped. Actually, the optical pickup 2 is in the shape acquisition point P while the optical disc 1 is rotating.
1, P2, and P3 are sequentially set, and a shape reading voltage (servo control voltage) with respect to one rotation of the disk is detected to calculate each shape calculation value. For warping in the circumferential direction, if a shape acquisition point that passes through the warped portion is designated, all warping can be determined (recognized) as voltage values.

FIG. 5 is a graph showing a disk shape obtained by providing a shape acquisition point at a certain point on the optical disk, moving the optical pickup 2 to this shape acquisition point, and rotating the optical disk once. In FIG. 5, 50 is a line indicating the disk shape of an ideal optical disk, and 51
Is a line showing the disk shape of an actual optical disk with surface wobbling and warping. Regarding the eccentricity of the optical disk, if the ideal circumference is the line 50, the deviation from the ideal circumference can be indicated by the line 51.

In FIG. 6, a shape acquisition point is provided at one point on the optical disk, the optical pickup 2 is moved to this shape acquisition point, and the optical disk is rotated once and read by the optical pickup 2 (shape calculation value). FIG. In FIG. 6, 60 is a line indicating the shape reading voltage (shape calculation value) for an ideal optical disk, and 61 is a line indicating the shape reading voltage (shape calculation value) for an actual optical disk with surface wobbling and warping. Regarding the eccentricity of the optical disk, if the shape reading voltage (shape calculation value) of the ideal circumference is the line 60,
The shape reading voltage (shape calculation value) deviated from the ideal circumference can be indicated by a line 61.

FIG. 7 is a graph showing the movement of the initial value of the servo control voltage with respect to the optical pickup 2 when a shape acquisition point is provided at one point on the optical disk, the optical pickup 2 is moved to this shape acquisition point, and the optical disk is rotated once. FIG. In FIG. 7, reference numeral 70 denotes a line indicating the original initial value of the servo control voltage, and reference numeral 71 denotes a line indicating the initial value of the servo control voltage obtained by adding the shape reading voltage (shape calculation value).

FIG. 8 is a flowchart for explaining the process of reading the shape of the optical disc in advance in the present embodiment. A process for reading the shape of the optical disc in advance will be described with reference to this flowchart.

In this optical disk recording / reproducing apparatus, in order to examine in advance the shape of the optical disk 1 to be reproduced or recorded, the rotational speed lowering means 221 of the system controller 22 controls the servo control unit 4 to set the rotational speed of the spindle motor 5 to a predetermined value. The rotational speed is decreased to a rotational speed (a rotational speed that is low enough for the optical pickup 2 to follow a track of the optical disc 1 having surface deflection, warpage, or eccentricity) (step S1).

Next, the shape acquisition point setting means 222 sets a shape acquisition point for the optical disc 1 (step S2). For example, three shape acquisition points P1, P2 on the optical disc 1 as shown in FIG.
, P3 corresponding to shape acquisition points are set. Note that the number of shape acquisition points is not limited to three, and the more the number of shape acquisition points, the higher the servo accuracy. Thereafter, the shape acquisition point moving means 223 controls the servo control unit 4 to drive the sled 3 to move the optical pickup 2 to the shape acquisition point (for example, the shape acquisition point P1) (step S3).

Next, the storage processing means 224 moves to the shape acquisition point and rotates the optical disk 1 for one rotation, for example, the value of the servo control voltage based on the output signal of the optical pickup (for example, the shape indicated by the line 61 in FIG. 6). The read voltage (shape calculation value) is stored in the RAM 27 (step S4).
). Thereafter, the system controller 22 determines whether or not the process for the number of shape acquisition points has been repeated (step S5). If the process has not been repeated, the process returns to the process of step S3. Here, since the processing for the shape acquisition point P1 is only completed, the process returns to step S3, and similarly, the values of the servo control voltages corresponding to the shape acquisition points P2 and P3 are RA.
After being stored in M27 (step S4) and finishing the processing for the number of shape acquisition points (step S5)
The disk shape value calculation means 225 calculates the shape value of the optical disk 1 based on the values of the plurality of servo control voltages stored in the RAM 27, and stores this shape calculation value in the RAM 27 (step S6).

When there are a plurality of shape acquisition points as described above, the deviation (surface runout, warpage, or eccentricity) of the optical disc 1 with respect to the servo control point is calculated based on each measured value (shape reading voltage), and thereby the servo control point is calculated. The shape reading voltage is calculated and the shape reading voltage is added to the initial servo control voltage, so that the follow-up performance of the optical pickup 2 with respect to the track of the optical disc 1 is enhanced, and the focus servo, tracking servo, etc. are not easily removed. be able to.

FIG. 9 is a flowchart for explaining processing for setting a servo control voltage during reproduction or recording in the present embodiment. Processing for setting a servo control voltage during reproduction or recording will be described with reference to this flowchart.

At the time of reproduction or recording, the adding means 226 reads the calculated shape value stored in the RAM 27 (step N1), and adds this calculated shape value to the value of the servo control voltage (step N2). The servo control means 227 controls the servo control unit 4 so that a servo control voltage based on the value of the servo control voltage added with the shape calculation value is output from the servo control unit 4 (step N3). As a result, the servo control unit 4 outputs a servo control voltage based on the value of the servo control voltage to which the calculated shape value is added. That is, since the calculated shape value is added to the servo control voltage, for example, the servo control voltage such that the original initial value of the servo control voltage as indicated by the line 70 is indicated by the line 71 as illustrated in FIG. Move to the initial value of. As a result, even if the optical disk being reproduced or recorded has surface wobbling, warping or eccentricity, the optical pickup 2 is controlled by the servo control voltage to which the initial value has moved, so that the track on the optical disk 1 can be quickly moved. Can follow.

As described above, according to the present embodiment, the servo control unit outputs the servo control voltage based on the servo control voltage value obtained by adding the calculated shape value of the optical disk, so that it can be applied to an optical disk having surface deflection, warpage, or eccentricity. Even when playback or recording is performed, the optical pickup can quickly follow the track of the optical disk, so that there are almost no mistakes during playback or recording, and smooth playback or recording processing without interruption. It can be performed.

It is a block diagram which shows the structure of the optical disk recording / reproducing apparatus which concerns on one Embodiment of this invention. It is a figure which shows the position of the shape acquisition point on the optical disk in the said embodiment. It is a figure which shows the state in case the optical disk has raise | generated the surface shake in the said embodiment. It is a figure which shows the state in case the optical disk has raise | generated the surface deflection and the curvature in the said embodiment. FIG. 3 is a graph showing a disk shape obtained by providing a shape acquisition point at a certain point on the optical disk in the embodiment, moving the optical pickup to the shape acquisition point, and rotating the optical disk once. In the embodiment, a shape acquisition point is provided at a certain point on the optical disk, the optical pickup is moved to this shape acquisition point, and the optical disk is rotated once and read by the optical pickup. It is the figure represented graphically. In the embodiment, a shape acquisition point is provided at one point on the optical disk, the optical pickup is moved to this shape acquisition point, and the movement of the initial value of the servo control voltage with respect to the optical pickup 2 when the optical disk is rotated once is a graph. FIG. 4 is a flowchart for explaining processing for reading in advance the shape of an optical disc in the embodiment. 4 is a flowchart for explaining processing for setting a servo control voltage during reproduction or recording in the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk 2 Optical pick-up 3 Thread 4 Servo control part 5 Spindle motor 22 System controller 27 RAM (memory)
221 Rotational speed reduction means 222 Shape acquisition point setting means 223 Shape acquisition point moving means 224 Storage processing means 225 Disk shape value calculation means 226 Adding means 227 Servo control means

Claims (4)

An optical pickup for optically reproducing / recording information on an optical disc, a sled for moving the optical pickup in the radial direction of the optical disc, and a spindle motor and the sled are driven according to instructions from a system controller And a servo control unit for performing focus control and tracking control on the optical pickup for moving the focal position of the laser light emitted from the optical pickup in the vertical direction and the horizontal direction with respect to the recording surface of the optical disc, respectively. In the optical disk recording / reproducing apparatus, the system controller controls the servo control unit to reduce the number of revolutions of the spindle motor to a predetermined number of revolutions in order to check in advance the shape of the optical disk to be reproduced or recorded. Lowering means, and Shape acquisition point setting means for setting a shape acquisition point for the optical disk to examine the shape of the disk, shape acquisition point moving means for controlling the servo control unit to move the optical pickup to the shape acquisition point, and Storage processing means for storing in the memory the servo control voltage value based on the output signal of the optical pickup obtained by moving to the shape acquisition point and rotating the optical disk by a predetermined rotation, and the servo control voltage value for the number of shape acquisition points A disk shape value calculating means for calculating a shape value of the optical disk based on a plurality of servo control voltage values stored in the memory and storing it in the memory after being stored in the memory; At the time of recording, adding means for reading the calculated shape value stored in the memory and adding it to the value of the servo control voltage; Optical disc recording and reproducing apparatus characterized by having a servo control means for controlling the servo control unit so as to servo-control voltage is outputted from the servo control unit according to the value of the calculated value obtained by adding a servo control voltage. An optical pickup for optically reproducing / recording information on an optical disc, a sled for moving the optical pickup in the radial direction of the optical disc, and a spindle motor and the sled are driven according to instructions from a system controller And a servo control unit for performing focus control and tracking control on the optical pickup for moving the focal position of the laser light emitted from the optical pickup in the vertical direction and the horizontal direction with respect to the recording surface of the optical disc, respectively. In the optical disk recording / reproducing apparatus, the system controller decreases the rotational speed of the spindle motor to a predetermined rotational speed and sets a shape acquisition point for the optical disk in order to examine in advance the shape of the optical disk to be reproduced or recorded. The shape The shape value of the optical disk is calculated based on the value of the servo control voltage based on the output signal of the optical pickup obtained by moving to the acquisition point and rotating the optical disk by a predetermined rotation. An optical disk recording / reproducing apparatus, wherein the servo control unit is added to a control voltage value, and the servo control unit is controlled so that the servo control voltage to which the shape calculation value is added is output from the servo control unit. The system controller controls the servo control unit to reduce the number of revolutions of the spindle motor to a predetermined number of revolutions in order to investigate in advance the shape of the optical disk to be reproduced or recorded, and the optical disk Shape acquisition point setting means for setting a shape acquisition point for the optical disc in order to examine the shape of the optical disk, shape acquisition point moving means for controlling the servo control unit to move the optical pickup to the shape acquisition point, and the shape acquisition Storage processing means for storing in the memory the value of the servo control voltage based on the output signal of the optical pickup obtained by moving the optical disk by a predetermined rotation by moving to a point, and the value of the servo control voltage for the number of shape acquisition points in the memory After being stored, based on the values of a plurality of servo control voltages stored in the memory, Optical disc recording and reproducing apparatus according to claim 2, characterized in that it comprises a disc-shaped value calculating means for the Jo value calculated is stored in the memory. The system controller includes an adding means for reading a calculated shape value stored in the memory and adding the calculated value to the servo control voltage value during reproduction or recording, and servo control based on the servo control voltage value to which the calculated shape value is added. 4. The optical disk recording / reproducing apparatus according to claim 3, further comprising servo control means for controlling the servo control unit so that a voltage is output from the servo control unit.

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