JP2003228835A - Optical disk unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk unit which avoids overwrite in recorded data caused by a scratch and dust on an optical disk. <P>SOLUTION: The optical disk unit for carrying out recording on the optical disk divided into a plurality of segment regions in which each track has a unique segment number comprises a segment number demodulation means to generate the segment numbers from the data of the plurality of segment regions, and a segment number counting means to count the number of segment regions and keep count values corresponding to the segment numbers. When the count values kept by the segment number counting means differs from the segment numbers generated by the segment number demodulation means during recording using a laser beam, the power of the laser beam is changed from a recording state to a non-recording state. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device for recording and reproducing information on an optical disk by using a laser beam, and more particularly to processing when an abnormality occurs during a recording operation.

[0002]

2. Description of the Related Art Conventionally, when information is recorded on an optical disk by using a laser beam, tracking control is missed due to external vibrations / impacts, scratches and dust existing on the optical disk itself, and the area is outside the area to be recorded. In order to avoid the inconvenience of laser light irradiation, the tracking error signal is monitored, and if the signal level exceeds a certain set value, it is judged that tracking error has occurred, and the laser light power control is performed. It was normal to do. As such an optical disk device, for example, there is one described in Japanese Patent Laid-Open No. 07-287856.

[0003]

However, in an optical disc apparatus which stops the recording state by monitoring only the signal level of the tracking error signal as described above, even if the signal level does not exceed a set value, the recording is stopped. There is a possibility that the recorded information may be erased or recording may fail in the area to be recorded. For example, the position information on the optical disc may be lost due to the loss of the optical disc itself. In this case, the position information becomes unknown, and a problem occurs that the information is recorded in the already recorded area.

In view of the above-mentioned problems, the present invention provides an optical disc device which avoids the possibility of erasing recorded information and recording failure in the area to be recorded. Further, the present invention provides an optical disk device capable of avoiding abnormal operation of tracking control due to scratches, dust, etc. existing on the optical disk itself.

[0005]

In order to solve the above problems, an optical disk device of the present invention is an optical disk device for recording on an optical disk in which each track is divided into a plurality of segment areas having a unique segment number. And segment number demodulating means for generating the segment number from the data of the plurality of segment areas, and segment number counting means for counting the number of the segment areas and holding a count value corresponding to the segment number. During recording using laser light, when the count value held by the segment number counting means and the segment number generated by the segment number demodulating means are different, the power of the laser light is changed from the recording state to the non-recording state. It has a configuration that changes to.

Thus, it is possible to avoid the possibility that the recorded information is erased and the recording in the area to be recorded fails.

Further, in order to solve the above problems, the optical disc apparatus of the present invention is such that adjacent tracks have different tracking error signal polarities, and the tracks are divided into a plurality of segment areas having unique segment numbers. An optical disc apparatus for recording on an optical disc, wherein a segment number demodulating means for generating the segment number from a plurality of data of the segment areas, and an initial value is set to the segment number of the segment number demodulating means, And a segment number counting means for holding a count value corresponding to the segment number by counting the number of regions, during recording using a laser beam, the count value held by the segment number counting means and the segment If the segment numbers generated by the number demodulation means are different, , Those having a structure that the power of the laser beam is changed from the recording state to the non-recording state, and stops the tracking control.

Further, the data in the segment area has track address information, position information in the rotation direction which is data common to adjacent tracks, and at least one of error detection code and error correction code of the data. The segment number demodulating means is configured to generate a segment number using the data of the segment area.

As a result, it is possible to avoid the possibility of erasing recorded information and failure of recording in the area to be recorded, and to avoid abnormal operation of tracking control due to scratches or dust existing on the optical disc itself. It is the one.

(Embodiment 1) In Embodiment 1, an example of an optical disk device of the present invention will be described.

FIG. 1 is a block diagram of an example of the optical disk device according to the first embodiment. In addition, FIGS. 2, 3 and 4 are configuration diagrams of an optical disc to be reproduced or recorded by the optical disc device of the present embodiment. First, the structure of the optical disc will be described with reference to FIGS. 2, 3, and 4.

FIG. 2 shows the structure of an optical disk used in the optical disk device of this embodiment. In FIG. 2, even-numbered tracks 202 and odd-numbered tracks 203 are formed on the optical disc 201.
And each track 202, 203 has one track
It is composed of 280 segmented segments 204.

FIG. 3 shows the structure of a segment of an optical disk used in the optical disk device of this embodiment. In FIG. 3, wobble pits 301 and 302 for generating a tracking error signal are provided at the beginning of the segment 204.
And address pits 303 in which address data are dispersed and arranged bit by bit are arranged.

Here, the wobble pit 301 or wobble pit 302 is also used for timing generation for generating a reference clock used when recording or reproducing in the optical disc device.

Address data is distributed to segment 2
Since it is arranged in 04, one segment 204
There is a time margin between the reproduction of 1 bit of the address pit 303 of 1 to the reproduction of the address pit 303 of the next segment 204. During this time, it becomes possible to perform processing such as calculation processing of the error detection code or the error correction code.

FIG. 4 shows a data structure of address data that is distributed and arranged. In FIG. 4, even track 2
The address data of 02 includes a segment number 401, an error detection code 402 for detecting an error of the segment number 401, a track number 403 of the even-numbered track 202, and an error detection code 40 of the track number 403.
It is composed of 4.

Similarly, the address data of the odd-numbered track 203 includes the segment number 401 and the segment number 40.
Error detection code 402 for detecting the error 1
And an error detection code 406 of the track number 405.

Here, the segment numbers 401 of the even number tracks 202 and the odd number tracks 203 have the same data value, and the error detection codes 402 of the even number tracks 202 and the odd number track 203 have the same data value.

The even tracks 202 and the odd tracks 203 correspond to track address information, and the segment number 401 corresponds to position information in the rotating direction.

In FIG. 4, a set of address data is formed by collecting the address pits 303 of 80 segments. Since one track is composed of 1280 segments, 16 address data can be generated per track.

Further, the track number 403 of the even-numbered track 202 and its error detection code 404, and the track number 405 of the odd-numbered track 203 and its error detection code 406 are arranged so that the address pits 303 do not exist in adjacent tracks. There is. by this,
It has a data structure that reduces address read errors due to crosstalk from adjacent tracks.

An optical disk device for recording information on the optical disk configured as described above by using laser light will be described below.

In FIG. 1, the rotation speed detecting section 111 detects the rotation speed of the optical disk 101 based on the rotation signal output from the motor 102. Motor control unit 112
Then, a rotation torque signal is generated according to the detected rotation speed from the rotation speed detection unit 111, and the motor 102 is driven to rotate. In this way, the motor control system is configured and the optical disc 101 is rotationally driven.

The detection signal RFA detected by the optical head 103 is input to the tracking error detector 104, the segment number demodulator 105 and the segment number counter 106.

The tracking error detector 104 uses the detection signal RFA to generate an error signal ER corresponding to the amount of radial deviation between the track on the optical disc 101 and the light spot on the optical disc 101. Specifically, the information of the wobble pit 301 and the information of the wobble pit 302 are detected from the detection signal RFA, and the signal corresponding to the difference signal between them is set as the error signal ER.

The segment number demodulation section 105 generates address data from the address pit information of the detection signal RFA, and the segment number 401 and the error detection code 402.
Is used to generate a demodulation segment number DSEG by demodulating the segment number 401.

In the segment number demodulation section 105,
Track numbers 403 and 405 and error detection code 40
Demodulated track numbers obtained by demodulating the track numbers 403 and 405 by using 4,406 are also generated (not shown).

In the segment number counting section 106, the demodulation segment number DSEG of the segment number demodulating section 105 is set as an initial value, and the number of segments 204 is counted based on the detection signal RFA. The number of the segments 204 can be easily counted because the amplitude of the detection signal RFA changes due to the influence of the wobble pits 301 and 302 or the address pits 303.

Count value CN of the segment number counting unit 106
T_V is used as information for identifying the position on the optical disc 101 when reproducing information on the optical disc 101 or recording information on the optical disc 101.

The tracking polarity switching section 108 uses the count value CNT_V of the segment number counting section 106 to
The polarity of the error signal ER of the tracking error detector 104 is switched to generate the tracking error signal TE.

As shown in FIG. 3, in the even-numbered tracks 202 and the odd-numbered tracks 203, the positional relationship between the wobble pits 301 and the wobble pits 302 is reversed. Therefore, in order to obtain the tracking error signal TE having the same polarity on the even-numbered track 202 and the odd-numbered track 203, it is necessary to invert the polarity of the error signal ER between the even-numbered track 202 and the odd-numbered track 203.

Since the segment number 401 is zero at the switching position between the even number tracks 202 and the odd number tracks 203 of the optical disc 101, the polarity of the error signal ER is switched at the position where the count value CNT_V of the segment number counting section 106 is zero. As a result, a desired tracking error signal TE can be obtained.

The tracking control unit 109 inputs the tracking error signal TE of the tracking polarity switching unit 108, performs predetermined phase lead compensation calculation, low frequency component enhancement calculation, etc., and outputs an objective lens drive signal in the optical head 103. To do.

As described above, the optical head 103, the tracking error detection unit 104, the segment number demodulation unit 105, the tracking polarity switching unit 108, and the tracking control unit 109 constitute a tracking control system.

By the operation of this tracking control system, the light spot on the optical disc 101 moves accurately on the even-numbered tracks 202 and the odd-numbered tracks 203 on the optical disc.

In the laser power control section 110 of FIG. 1, the current to the laser light emitting element is controlled so that the intensity of the laser beam from the optical head 103 becomes a desired value.

The abnormality detecting section 107 compares the demodulation segment number DSEG of the segment number demodulating section 105 with the count value CNT_V of the segment number counting section 106. Since the demodulation segment number DSEG of the segment number demodulation unit 105 is output for every 80 segments,
The comparison operation of the abnormality detection unit 107 is performed for each detection operation of the segment number demodulation unit 105 (for each output of 80 segments).
To be done.

If the demodulation segment number DSEG and the count value CNT_V are different as a result of the comparison operation of the abnormality detecting unit 107, the output signal EM is set to "H" level. When the demodulation segment number DSEG and the value of the count value CNT_V match, the output signal EM is set to the “L” level.

In the laser power controller 110, when the output signal EM of the abnormality detector 107 becomes "H", the intensity of the laser light is switched to the intensity for reproduction.

With the above configuration, the rotation control of the optical disc 101, the tracking control for the even-numbered tracks 202 and the odd-numbered tracks 203, and the laser power control are performed.

Further, by configuring as described above,
It is possible to avoid the possibility that the recorded information is erased or the recording fails in the area to be recorded when the optical disc 101 has scratches or dust. Hereinafter, this will be described in detail.

The recording failure on the optical disc 101 occurs when the position information on the optical disc 101 becomes incorrect. That is, when there is an error in the detection signal RFA of the optical head 103 due to scratches or dust existing on the optical disk itself, the segment number counting unit 106 cannot perform the segment counting operation accurately. Therefore, the position on the optical disk 106 becomes inaccurate.

Count value CN of segment number counting unit 106
When T_V becomes incorrect, the next segment number demodulation unit 1
The demodulation segment number DSEG of 05 does not match.

Count value CNT_V and demodulation segment number D
If the SEGs are different, the abnormality detection unit 107 sets the output signal EM to "H". In the laser power control unit 110,
Since the output signal EM of the abnormality detection unit 107 becomes "H", the intensity of the laser light is switched to the intensity during reproduction. This interrupts the recording operation and shifts to the reproduction operation.

In this way, when the position information on the optical disc 101 becomes inaccurate due to scratches or dust on the optical disc 101, the recording operation is stopped and the reproducing operation is started.

In the reproducing operation, since the intensity of the laser beam is low, the recorded data will not be erased.

In the first embodiment, the abnormality detecting section 107 detects the coincidence between the demodulation segment number DSEG of the segment number demodulating section 105 and the count value CNT_V of the segment number counting section 106. When the demodulation unit 105 detects a code error or the like, the demodulation unit 105 is configured to output a predetermined segment number.
It is possible to stop the recording operation by detecting an anomaly both when a code error is detected by the segment number demodulation unit 105 and when a segment number counting error is detected. Even if the segment number demodulation unit 105 is configured in this way, it is included in the present invention.

When performing the counting operation of the segment number counting section 106, the incoming segments are not directly counted but are counted through a PLL circuit or the like so that the missing segments of the incoming segments are interpolated at predetermined time intervals. It may be constructed to provide protection against small scratches on the optical disc, which is still included in the present invention.

(Second Embodiment) In the second embodiment, another example of the optical disk device of the present invention will be described.

FIG. 5 is a block diagram of an embodiment of the optical disk device of the present invention according to the second embodiment. Optical disc 1 of FIG.
01 is the same as the optical disc 101 of the first embodiment, and the description thereof is omitted.

In FIG. 5, a motor 102, an optical head 103, a tracking error detector 104, a segment number demodulator 105, and a segment number counter 106.
Anomaly detection unit 107 and tracking polarity switching unit 10
8, a laser power control unit 110, and a rotation speed detection unit 1
11 and the motor control unit 112 have the same configurations as those of the first embodiment, and the description thereof will be omitted.

The tracking control 501 in FIG. 5 has a different configuration from the tracking control unit 109 of the first embodiment.

The tracking control 501 in FIG. 5 inputs the tracking error signal TE of the tracking polarity switching unit 108, performs predetermined phase lead compensation calculation, low frequency component enhancement calculation, etc., and outputs the objective lens drive signal in the optical head 103. Is output. Further, in the tracking control 501, when the output signal EM of the abnormality detection unit 107 is “H”, the arithmetic processing in the tracking control 501 is stopped and the tracking control is interrupted.

Similar to the first embodiment, also in the second embodiment, the rotation control of the optical disc 101, the tracking control to the even tracks 202 and the odd tracks 203, and the laser power control are performed by the above configuration. There is.

Further, with the configuration as described above, it is possible to avoid the possibility of erasing recorded information and recording failure in the area to be recorded.
Is the same as.

Further, in the configuration of the second embodiment, when the abnormality detecting unit 107 detects an abnormality, the operation of the tracking control unit 501 is stopped. This is because the tracking polarity switching unit 108 detects the switching point between the even numbered tracks 202 and the odd numbered tracks 203 based on the count value CNT_V of the segment number counting unit 106, so that the count value CNT_V of the segment number counting unit 106 is set. When a counting error occurs, the correct switching point between the even track 202 and the odd track 203 cannot be detected. as a result,
It becomes difficult to generate an accurate tracking error signal TE,
This is because highly accurate tracking control cannot be performed.

By configuring the tracking control unit 501 as in the second embodiment, since the tracking control is stopped at such an abnormal tracking error signal TE, an abnormal operation is generated in the tracking control. Can be suppressed.

In tracking control, if an abnormal tracking error signal TE is input, the objective lens in the optical head 103 may be driven to the movable limit, and the durability and reliability of the optical disk device may be greatly impaired. Become.

Although the tracking control unit 501 according to the second embodiment stops the calculation of tracking control according to the output signal of the abnormality detection unit, the calculation is performed only near the switching point between the even-numbered track and the odd-numbered track. The possibility of the re-pull-in operation of the tracking control may be reduced by enabling the stop operation. Even if the tracking control unit is configured in this way, it is included in the present invention.

[0060]

As described above, in the optical disc apparatus of the present invention, the abnormality detecting section compares the demodulated segment number with the count value of the segment number counting section to change the recording state to the non-recording state. Erroneous recording can be avoided. As a result, the optical disc device is less likely to cause erroneous recording even if the optical disc itself has scratches or dust.

Further, the tracking control unit also stops the tracking operation by the output signal of the abnormality detecting unit. As a result, the adverse effect on the mechanism can be reduced, and the optical disc device becomes highly reliable.

By the above operation, the reliability of the recording operation of the optical disk device is dramatically improved.

[Brief description of drawings]

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

FIG. 2 is a structural diagram of an optical disc to be recorded by the optical disc device of the present invention.

FIG. 3 is a structural diagram of an optical disc segment recorded by the optical disc device of the present invention.

FIG. 4 is a structural diagram of address data of an optical disc.

FIG. 5 is a configuration diagram of an optical disk device according to another embodiment of the present invention.

[Explanation of symbols]

101 optical disc 102 motor 103 optical head 104 tracking error detector 105 segment number demodulator 106 segment number counting unit 107 Abnormality detector 108 Tracking polarity switching unit 109, 501 tracking control unit 110 Laser power control unit 111 Rotation speed detector 112 Motor control unit

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5D044 BC04 CC04 DE38 DE61 DE70                       EF10 FG19 GK19 HH13 JJ01                 5D090 AA01 BB04 CC01 DD03 DD05                       FF02 FF09 FF38 FF43 GG28                       HH02 JJ02 KK05                 5D118 AA27 AA28 BA01 BB05 BC12                       BF03 CA07 CA13 CD07

Claims (3)

[Claims] 1. An optical disk device for recording on an optical disk in which each track is divided into a plurality of segment areas each having a unique segment number, wherein the segment number is generated from data of the plurality of segment areas. Demodulation means, comprising a segment number counting means for counting the number of the segment area and holding a count value corresponding to the segment number, during recording using a laser beam, the segment number counting means holds An optical disk device, wherein when the count value and the segment number generated by the segment number demodulating means are different, the power of the laser beam is changed from a recording state to a non-recording state. 2. An optical disk device for recording on an optical disk in which polarities of tracking error signals are different between adjacent tracks, and the tracks are divided into a plurality of segment areas having unique segment numbers. A segment number demodulation means for generating the segment number from the data of the segment area, and an initial value is set to the segment number of the segment number demodulation means, and a total number corresponding to the segment number is obtained by counting the number of the segment areas. A segment number counting means for holding a numerical value, during recording using a laser beam, when the segment number generated by the segment number demodulating means and the count value held by the segment number counting means is different, the The power of the laser beam is changed from the recorded state to the non-recorded state.
And an optical disk device characterized by stopping tracking control. 3. The data in the segment area includes track address information, position information in the rotating direction which is data common to adjacent tracks, and at least one of an error detection code and an error correction code of the data. 3. The optical disk device according to claim 1, wherein the segment number demodulating means generates a segment number using the data of the segment area.