JP2003067953A - Optical disk apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical disk apparatus which can prevent the traverse follow-up for an unusual TE signal and which can perform a stable seeking operation. SOLUTION: The optical disk apparatus performing the tracking control for a data recording line spirally recorded on a recording surface of an optical disk 1 or the focus control for the recording surface includes a judgment part 28 which judges whether a tracking pull-in process performed in the tracking control has been completed normally or not and a traverse gain cut circuit 36 which cuts a traverse drive gain on the basis of the judgment result of the judgment part 28.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a DVD, a CD-RO.
The present invention relates to an optical disk device for recording / reproducing an optical disk such as M.

[0002]

2. Description of the Related Art Seek control in a conventional optical disk device is performed by driving a traverse motor to drive a screw shaft and a bobbin.
A seek operation is performed, and thereafter, tracking pull-in processing, tracking pull-in confirmation processing, and tracking flow detection are performed. The traverse motor, screw shaft, and bobbin form a traverse system.

FIG. 15 is a block diagram showing a conventional optical disk device. In FIG. 15, 1 is an optical disk, 2 is an optical pickup, 3 is an objective lens, 4 is a tracking actuator driver, 5 is a tracking servo circuit, and 6
Is a focus driver, 7 is a focus servo circuit, 8
Is a bobbin, 9 is a traverse motor, 10 is a traverse motor driver, 11 is a screw shaft, 12 is a seek control circuit, 13 is a spindle motor, 14 is a front end processor (FEP), 18 is a tracking pull-in determination circuit, and 19 is a tracking flow. It is a detection circuit.

A seek operation and a tracking operation of the optical disc device having the above structure will be described.
The light emitted from the optical pickup 2 onto the optical disc 1 is reflected by the optical disc 1 and returned to the objective lens 3. A photodetector (not shown) incorporated in the optical pickup 2 obtains displacement information necessary for performing focus control and tracking control described later from the light received by the objective lens 3. The focus control and tracking control will be described below.

The focus driver 6 is controlled by a signal output from the focus servo circuit 7, and sets the objective lens 3 mounted on the optical pickup 2 to the optical disk 1.
A focus coil (not shown) drives the lens in the focus direction (vertical direction) so as to focus on. The tracking servo circuit 5 controls a tracking actuator driver 4 that drives a tracking coil (not shown) provided in the optical pickup 2 and moves the optical pickup 2 on the bobbin 8 along the screw shaft 11 (in the disc radial direction). The seek control circuit 12 that controls the traverse motor 9 to be moved is controlled.

That is, the signal from the tracking servo circuit 5 is sent to the tracking actuator driver 4 as described above.
The objective lens 3 is driven in the tracking direction (disk radial direction) by the tracking coil via the tracking coil and the seek control circuit 12 and the traverse motor driver 1
Through 0, the traverse motor 9 moves the optical pickup 2 on the screw shaft 11.

As described above, while focusing on the data sequence spirally recorded on the recording surface of the optical disc 1, the follow-up control to the data sequence is performed. The seek control circuit 12 controls the movement of the optical pickup 2 during rough seek, and the traverse motor driver 10
Optical pickup 2 on the screw shaft 11 via
The optical pickup 2 is moved to the vicinity of the address where the target data exists. At the time of initial startup after mounting the disc, the seek control circuit 12 performs eccentricity amount measurement for measuring the disc deviation, tracking balance adjustment for adjusting the balance of the tracking signal with respect to the tracking offset, and initial tracking pull-in. Done. After that, the tracking servo circuit 5 starts the information track follow-up control. After mounting the optical disk in this way, initial startup, coarse seek control, optical pickup 2
The information signal can be reproduced by controlling the following of the information track of the optical disc 1.

FIG. 16 is a block diagram showing the tracking servo system of FIG. In FIG. 16, the tracking actuator driver 4, the traverse motor 9,
Traverse motor driver 10, seek control circuit 12,
FEP (front end processor) 14, tracking pull-in determination circuit 18, tracking flow detection circuit 1
9 is the same as that in FIG.

Reference numeral 20 is a tracking equalizer, 21 is a tracking coil control amplifier, 22 is a tracking coil, 23 is a motor control equalizer, and 24 is a motor control amplifier. The above components 20, 21, 23,
Reference numeral 24 constitutes the tracking servo circuit 5.

The operation of the tracking servo system thus constructed will be described. The tracking error signal output from the FEP 14 (hereinafter, "TE signal")
(Hereinafter referred to as “TC signal”), the tracking equalizer 20 generates a signal (hereinafter, referred to as “TC signal”) for controlling the minute movement of the objective lens 3 in the disk radial direction, and the signal is sent to the tracking coil 22. . Also, TE
The signal is branched and input to the motor control equalizer 23 and controls the movement of the optical pickup 2 on the screw shaft 11 (hereinafter, referred to as “PMC signal”).
Is generated and sent to the traverse motor 9 via the traverse motor driver 10.

These TC signal and PMC signal are given appropriate gains by a tracking coil control amplifier 21 and a motor control amplifier 24, respectively, and the tracking coil driver 22 and the traverse motor 22 are driven by a tracking actuator driver 4 and a traverse motor driver 10, respectively. Feedback control is performed by driving 9 and returning the TC signal and the PMC signal at the time of driving to the tracking equalizer 20 and the motor control equalizer 23. As described above, the information tracks arranged in a spiral on the optical disc 1 can be followed.

Further, the traverse motor driver 10 is
Input a seek command signal via the seek control circuit 12,
The seek operation is performed by rotating the motor at high speed. After the seek operation, a process for pulling in the tracking is performed, and the tracking pull-in determination circuit 18 determines whether or not the tracking is correctly pulled in. After that, in the tracking following processing, the tracking flow detection circuit 19 detects whether or not the tracking operation to the information track is correctly performed.

FIG. 17 is a block diagram showing the tracking pull-in determination circuit 18 of FIG. In FIG. 17, reference numeral 25 is a track jump number counter, 26 is a comparator, 27 is a repeat routine section, 28 is a determination section, 29 is a tracking pull-in processing start signal, 30 is a confirmation time width setting register for setting a confirmation time width, 31 Is a normal jump number setting register for setting the normal jump number.

The conventional tracking pull-in determination operation will be described below with reference to FIG. The TE signal output from the FEP 14 is the track jump number counter 25.
Entered in. The track jump number counter 25 counts the number of tracks jumped after the tracking pull-in process by counting the TE signal at a constant threshold level. Here, the above-mentioned fixed threshold level is an arbitrary potential level in the entire amplitude range of the TE signal, and is not particularly defined.
If the tracking is pulled in normally, do not cross the track (do not jump the track)
Therefore, the count value should ideally be 0. However, in the process from the start to the end of the track pull-in process, some tracks are crossed due to a disk rotation waiting time until stable track pull-in becomes possible, servo disturbance, and the like.

The counting of the TE signal is started by the tracking pull-in processing start signal 29 input to the track jump number counter 25, and the counting is ended by the confirmation time width setting which is a register set in the tracking servo circuit 5. It is determined by the confirmation time width setting value d1 stored in the register 30. Track jump counter 2
The number of track jump counts obtained from 5 is
The value is input to the comparator 26 and is also compared with the normal jump number setting value d2 input from the normal jump number setting register 31 to the comparator 25. The normal jump number setting register 31 is a register set in the tracking servo circuit 5. As a result, the determination unit 28 determines that the tracking pull-in process has ended normally if the track jump count count is equal to or less than the normal jump count set value d2. If it is not regarded as a normal end, the same processing is repeated by the set number of times by the routine of the repeat routine unit 27.

FIG. 18 is a block diagram showing the tracking flow detection circuit 19 of FIG. In FIG. 18, 25 is a track jump number counter, 26 is a comparator, 32 is a tracking flow detection time setting register, 33 is a normal tracking flow number setting register, 34 is a tracking flow detection start signal, 28 is a judging section, and 45 is a return. It is a routine section. The conventional tracking flow detection operation will be described below.

The TE signal output from the FEP 14 is input to the track jump number counter 25. The operation of the track jump number counter 25 is the same as that of the track jump number counter 25 of FIG. 17, and thus the description thereof is omitted. The counting of the TE signal is started by the tracking flow detection processing start signal 34 inputted to the track jump number counter 25, and the counting is ended by the tracking flow detection time setting which is a register set in the tracking servo circuit 5. Register 32
It is determined by the storage flow detection time setting value d3. The track jump count number obtained by the track jump number counter 25 is input to the comparator 25 and compared with the normal flow number set value d4 which is also input to the comparator 25 from the normal flow number setting register 33. The normal flow number setting register 33 is a register set in the tracking servo circuit 5.

As a result, when the number of track jump counts is equal to or less than the normal flow line number set value d4 in the determination unit 28, it is determined that the tracking follow-up is normally executed. Further, when it is not regarded as the normal operation, the re-routing processing of the tracking is performed by the routine of the return routine unit 45. As described above, the startup process after the disk is mounted and the tracking pull-in process after the rough seek are performed, and then the track following operation is performed.

Hereinafter, the optical pickup 2 based on the TE signal
A control system that causes the objective lens 3 of FIG. 1 to follow the information track of the optical disc 1 by the tracking coil 5 is called a lens servo system. A control system that causes the traverse to follow the position of the objective lens 3 is a traverse servo system, and an optical pickup on the traverse. A control system that moves 2 at high speed is called a seek control system.

In the information signal reproducing operation of the optical disc apparatus, it is necessary to improve the playability by promptly completing the initial start-up process after the disc is mounted and performing the tracking pull-in after the rough seek control. In the initial startup processing, tracking balance adjustment for adjusting the balance of the tracking signal,
Tracking / focus gain adjustment for adjusting the gain balance of the tracking system and focus servo system, lens shift adjustment for adjusting the optical neutral point of the objective lens 3, and the like are performed. The lens shift adjustment is an adjustment for searching an optical neutral point of the objective lens 3 with respect to the bobbin 8 based on the TE signal detected by the phase difference method.

However, in the recordable optical disc 1 represented by the DVD-RAM, the TE signal detected by the phase difference method and the TE signal detected by the push-pull method are distinguished by the disc recording area and used. It is divided. The recording area of the TE signal detected by the phase difference method in the DVD-RAM disk is about 22.6 mm to 2 from the disk center in the disk recording area.
It is a region having a width of only 1.4 mm near the innermost periphery of 4 mm, and is a region in which pits are formed in advance, and is called an EMBOSS region. T detected by the push-pull method
The recording area of the E signal is approximately 24 mm to 5 mm from the center of the disc.
It exists in a wide area of 7.6 mm and is called the RW area.
That is, in the lens shift adjustment in the DVD-RAM, it is necessary to quickly move to the EMBOSS region existing near the innermost circumference of the disc. The focus / tracking gain adjustment is for setting an appropriate gain in the focus servo system and the tracking servo system, and is performed in the innermost peripheral portion of the disk where data existence is high in the RW area.

As described above, the above various adjustments performed at the time of initial startup are performed, and in order to end the initial startup processing early, the optical pickup 2 is rapidly moved to the inner peripheral portion of the disk, and after the rough seek. It is necessary to perform tracking pull-in. However, there is an area called a mirror area in which the recorded data does not exist at all in the innermost circumference of the disk.
When a rough seek to the innermost circumference occurs and the optical pickup 2 moves to the mirror area, the TE signal is not output at all. Therefore, the track count signal, which is the determination reference in the tracking pull-in process and the tracking flow detection process, is set. There is a case that the judgment cannot be obtained because the information cannot be obtained. Then, the traverse erroneously determines that the tracking follow-up is normally performed, and follows the TE signal outputting the abnormal signal. As a result, the traverse may start to operate unexpectedly and cause damage to the traverse moving mechanical system and the optical pickup system.

[0023]

As described above, since the TE signal is not output at all when the optical pickup 2 is moved to the mirror area, the track count signal cannot be obtained and the determination may be erroneous. Had the problem.

In this optical disk device, it is required to prevent traverse follow-up to an abnormal TE signal and perform a stable seek operation.

In order to meet this requirement, the present invention prevents traverse runaway due to traverse following to an abnormal TE signal, avoids damage given to the traverse moving mechanical system and eventually the optical pickup, and performs a stable seek operation. It is an object of the present invention to provide an optical disk device capable of achieving the above.

[0026]

In order to solve the above problems, an optical disk device of the present invention receives a laser reflected light from an optical disk by a photodetector and converts an optical signal detected by the photodetector into an electric signal. Tracking control is performed in an optical disk device that performs tracking control of a data recording row spirally recorded on the recording surface of the optical disk and focus control to the recording surface by using the change in the electric signal obtained by the conversion. A determination device for determining whether or not the tracking pull-in process is normally completed,
And a traverse gain cut circuit that cuts the traverse drive gain based on the determination result of the determination device.

As a result, it is possible to obtain an optical disk device capable of preventing an unexpected operation due to the traverse following an abnormal TE signal and performing a stable seek operation.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical disk device according to claim 1 of the present invention receives a laser reflected light from an optical disk by a photodetector, converts an optical signal detected by the photodetector into an electric signal, and converts the electric signal. Tracking performed by tracking control in an optical disk device that performs tracking control of a data recording row spirally recorded on the recording surface of the optical disk and focus control on the recording surface by using the change of the obtained electric signal The determination device determines whether or not the pull-in process is normally completed, and the traverse gain cut circuit that cuts the traverse drive gain based on the determination result of the determination device.

With this configuration, the determination device detects an abnormality in the tracking pull-in process, the tracking pull-in confirmation process, the tracking flow detection process, and the information track follow-up operation, and there is no information data at all in the mirror area. The traverse gain cut circuit can cut the traverse gain when the rush of the optical pickup into the optical pickup is detected and the abnormalities are detected, preventing the unexpected movement due to the traverse following the abnormal TE signal. However, it has an effect that a stable seek operation can be performed.

According to a second aspect of the present invention, in the optical disc apparatus according to the first aspect, the traverse gain cut circuit starts the operation based on the determination result at least before the tracking pull-in process at the rough seek time. It is a thing.

With this configuration, the traverse drive gain can be cut based on the abnormal TE signal at least before the tracking pull-in at the time of the rough seek, so that an unexpected operation due to the traverse following of the abnormal TE signal can be prevented. It has the effect that

According to a third aspect of the present invention, in the optical disc apparatus according to the first aspect, the traverse gain cut circuit starts an operation based on the determination result at least before the tracking pull-in confirmation processing performed after the tracking pull-in processing. It was decided.

With this configuration, since the traverse drive gain can be cut based on the abnormal TE signal at least before the tracking pull-in confirmation processing performed after the tracking pull-in processing, an unexpected operation due to the traverse following of the abnormal TE signal is performed. Has the effect of being able to prevent

According to a fourth aspect of the present invention, in the optical disc apparatus according to the first aspect, the determining device determines whether the optical pickup movement to the mirror area occurs based on a tracking error signal used in tracking control. It has an area determination circuit.

With this configuration, the mirror area can be determined from the tracking error signal, so that the mirror area can be easily determined.

According to a fifth aspect of the present invention, in the optical disc apparatus according to the fourth aspect, the traverse gain cut circuit operates to set the traverse drive gain to 0 when the optical pickup moves to the mirror area. It was decided to start.

With this configuration, the traverse drive gain is cut when the optical pickup moves to the mirror area, so that an unexpected operation can be surely prevented.

An optical disk device according to a sixth aspect of the present invention is the optical disk device according to the first aspect, wherein the traverse gain cut circuit makes a determination for at least a predetermined time in a tracking flow detection process performed after a tracking pull-in confirmation process at the time of rough seek. The operation is based on the result.

With this configuration, the traverse drive gain is cut based on the abnormal TE signal for a certain period of time in the tracking flow detection process performed after the tracking pull-in confirmation process at least during the rough seek, so that the traverse to the abnormal TE signal is performed. This has the effect of preventing an unexpected movement due to tracking.

An optical disk device according to a seventh aspect of the present invention receives a laser reflected light from an optical disk having a pre-pit address by a photodetector, converts an optical signal detected by the photodetector into an electric signal, and obtains it by conversion. By using the change in the electric signal, the tracking flow carried out by the tracking control is performed in the optical disk device that performs tracking control of the data recording sequence spirally recorded on the recording surface of the optical disk and focus control on the recording surface. It has a judging device for judging whether or not it has been detected, and a pre-pit address detection counting circuit for counting the pre-pit address detection based on the judgment result in the judging device.

With this configuration, the pre-pit address can be detected at least during the tracking control and the number of times of detection can be counted, so that there is an effect that an abnormality in the tracking or the mirror area can be detected and detected.

An optical disk device according to an eighth aspect of the present invention is the optical disk device according to the seventh aspect, wherein the pre-pit address detection count circuit is activated at least when a tracking flow is detected during tracking control. is there.

With this configuration, at least the pre-pit address detection can be counted at the time of detecting the tracking flow, so that the tracking or the abnormality in the mirror area can be detected / detected at the time of detecting the tracking flow.

According to a ninth aspect of the present invention, in the optical disc apparatus according to the seventh aspect, the pre-pit address detection count circuit is activated at least when the tracking flow is detected immediately after the tracking pull-in process. .

With this configuration, at least the pre-pit address detection can be counted at the time of detecting the tracking flow immediately after the tracking pull-in process. Therefore, at the time of detecting the tracking flow immediately after the tracking pull-in process, an abnormality in the tracking or mirror area is detected / detected. It has the effect of being able to.

FIG. 1 shows the embodiment of the present invention.
~ It demonstrates using FIG.

(Embodiment 1) FIG. 1 is a block diagram showing an optical disk device according to Embodiment 1 of the present invention. Figure 1
In optical disc 1, optical pickup 2, objective lens 3, tracking actuator driver 4, tracking servo circuit 5, focus driver 6, focus servo circuit 7, bobbin 8, traverse motor 9, traverse motor driver 10, screw shaft 11,
The seek control circuit 12, the spindle motor 13, and the front end processor (FEP) 14 are the same as those in FIG. Reference numeral 15 is a tracking pull-in determination circuit for determining whether or not tracking pull-in is normally performed, and reference numeral 16 is for detecting whether or not the optical pickup 2 correctly follows the information track in the track following operation after the tracking pull-in processing. The tracking flow detection unit 17 is a tracking servo abnormality detection circuit as a pre-pit address detection counting circuit that counts pre-pit address detection.

Next, the difference between this embodiment and the conventional technique will be described. FIG. 2 is a block diagram showing the tracking pull-in determination circuit 15 of FIG. In FIG.
25 is a track jump number counter, 26 is a comparator,
Numeral 28 is a judging section which constitutes the judging apparatus, 34 is a repeating routine section which stores the repeating routine, 35 is a mirror area judging circuit which constitutes the judging apparatus, 36 is a traverse gain cut circuit, 29 is a tracking pull-in processing start signal, and 30 is A confirmation time width setting register for storing the confirmation time width setting value d1 and a reference numeral 31 for a normal flight number setting register for storing the normal jump number setting value d2. Hereinafter, the operation of the tracking pull-in determination according to the present embodiment will be described with reference to FIG.

The TE signal output from the FEP 14 is input to the track jump number counter 25. The track jump number counter 25 counts the number of tracks jumped after the tracking pull-in process by counting the TE signal at a constant threshold level. Here, the constant threshold level is TE
It is an arbitrary potential level in the entire amplitude range of the signal, and is not particularly defined. When tracking is normally pulled in, the track does not cross the track, so the count value should ideally be 0. However, in the process from the start to the end of the track pull-in process, some tracks are crossed due to a disk rotation waiting time until stable track pull-in becomes possible, servo disturbance, and the like.

The counting of the TE signal is started by the tracking pull-in processing start signal 29 input to the track jump number counter 25, and the counting is ended by the confirmation time width setting which is a register set in the tracking servo circuit 5. Confirmation time width setting value d1 of register 30
Determined by The track jump count number obtained by the track jump number counter 25 is input to the comparator 25, and the normal jump number setting value d2 is also input to the comparator 25 from the normal jump number setting register 31.
Compared to. The normal jump number setting register 31 is a register set in the tracking servo circuit 5. As a result, the determination unit 28 determines that the tracking pull-in process has ended normally if the track jump count count is equal to or less than the normal jump count set value d2. If it is not regarded as a normal end, the same routine is repeated for the set number of times by the routine of the repeat routine section 34, and at the same time, the pull-in abnormality signal 37 is output to the traverse gain cut circuit 36.

During the tracking pull-in process,
When the optical pickup 2 enters a mirror area where no data exists, the mirror area determination circuit 35 outputs a mirror detection signal (not shown), and this mirror detection signal is input to the traverse gain cut circuit 36. . The traverse gain cut circuit 36 works to invalidate the traverse drive gain when either the mirror detection signal or the pull-in abnormality signal 37 is input. As a method of invalidating the traverse drive gain, there is a method of setting the gain setting value in the digital filter that controls the traverse servo control to 0, or cutting the traverse drive electric signal system directly by an external switch.

FIG. 3 is a block diagram showing the mirror area determination circuit 35 of FIG. In FIG. 3, 38 is a comparator,
Reference numeral 39 is a TE signal, 40 is a mirror determination reference signal, and 41 is a mirror determination signal. The operation of the mirror area determination circuit 35 thus configured will be described with reference to FIGS. 4 and 5. FIG. 4 is a waveform diagram showing the TE signal in the data region, and FIG. 5 is a waveform diagram showing the TE signal in the mirror region.

The TE signal 39 output from the FEP 14 is input to the comparator 38. The other signal input to the comparator 38 is a mirror determination reference signal 40, which is a reference signal for determining whether or not the optical pickup 2 is in the mirror area.

Here, FIG. 4 shows the case where the optical pickup 2 is present in the data area and TE at the time of tracking off.
The waveform of the signal is shown, showing that the TE signal appears as a track crossing signal due to a change in light amount in the data area. FIG. 5 shows the waveform of the TE signal when the optical pickup 2 is present in the mirror area. Since the laser light emitted from the optical pickup 2 is totally reflected in the mirror area, the TE signal has a high potential. It shows how it exists at the level.

As described above, when the optical pickup 2 plunges into the mirror portion, the potential level of the TE signal changes remarkably, so that it can be easily compared with the potential change level of the TE signal when the optical pickup 2 exists in the data area. It can be distinguished. Further, the tracking pull-in determination circuit 15 in the present embodiment works to quickly cut the traverse gain when a tracking pull-in abnormality or a mirror area plunge of the optical pickup 2 occurs during the tracking pull-in process.

FIG. 6 is a block diagram showing the tracking flow detection circuit 16 of FIG. In FIG. 6, reference numeral 25 is a track jump number counter, 26 is a comparator, 28 is a judgment unit which constitutes a judgment device, 35 is a mirror area judgment circuit which constitutes the judgment device, 36 is a traverse gain cut circuit, and 42 is a tracking flow detection. A start signal, 43 is a tracking flow detection time setting register that stores a tracking flow detection time setting value d3, 44 is a normal tracking flow number setting register that stores a normal tracking flow number setting value d4, and 45 is a return routine that stores a return routine. A reference numeral 46 is a determination start / end instruction unit for instructing start and end of determination, and 47 is a switch.

The operation of the tracking flow detection circuit 16 thus constructed will be described. FEP14
The TE signal thus output is input to the track jump number counter 25. Track jump counter 2
Reference numeral 5 counts the TE signal at a constant threshold level to count the number of tracks jumped after the tracking pull-in process. Here, the above-mentioned fixed threshold level is an arbitrary potential level in the entire amplitude range of the TE signal, and is not particularly defined. When tracking is normally pulled in, the track does not cross the track, so the count value should ideally be 0.

However, in the case of the DVD-RAM, since there are prepits in each sector, 25 to 59 prepit crossing signals are always generated on the TE signal per one rotation of the disc. That is, in the tracking pull-in state, it functions as a pre-pit address detection counter.
Further, since the track crossing signal always appears on the TE signal in the state where the tracking is not pulled in, by setting the detection time d3 by the track flow detection time setting register 43, it is possible to judge whether it is normal or abnormal. It is like this.

The counting of the TE signal is started by the tracking flow detection start signal 42 input to the track jump number counter 25, and the tracking flow detection start signal 42 is detected by the tracking flow detection after the tracking pull-in confirmation process. It is output at the timing of the start of processing. Further, the end of the count is determined by the track flow detection time setting value d3 of the track flow detection time setting register 43 which is a register set in the tracking servo circuit 5.

The number of track jump counts obtained by the track jump number counter 25 is calculated by the comparator 2
5 and is also compared with the normal flow number setting value d4 input from the normal flow number setting register 44 to the comparator 25. The normal flow number setting register 44 is a register set in the tracking servo circuit 5. As a result, the determination unit 28 determines that the tracking servo normally follows the information track in the tracking flow detection process if the track jump count number is equal to or less than the normal flow number set value d4.

When the tracking flow is detected (when the track jump count number is equal to or more than the normal flow number set value d4), the determination section 28 outputs the tracking flow detection signal to the traverse gain cut circuit 36 and at the same time. After the tracking servo is once turned off by the routine of the return routine unit 45, the tracking pull-in process is performed again. If the above process is not completed normally even after repeating the set number of times or the set time, an error is returned and the process ends.

Further, in the tracking flow detection processing performed immediately after the tracking pull-in determination processing after the rough seek, when the tracking flow detection start signal 42 is input from the determination start / end command section 46, for a set time,
By closing the switch 47, the information of the mirror area determination circuit 35 is output to the traverse gain cut circuit 36.

The traverse gain cut 36 works to invalidate the traverse drive gain when either the mirror detection signal or the tracking flow detection signal is input. The operation of the mirror area determination circuit 35 is performed by the mirror area determination circuit 3 used in the tracking pull-in determination circuit 15.
Since it is the same as that of 5, the description thereof is omitted.

As described above, according to the tracking flow detection process of the present embodiment, the abnormality in tracking the information track during the tracking flow detection process and the mirror area of the optical pickup 2 during the tracking flow detection process immediately after the tracking pull-in determination are performed. When a rush operation occurs, it works to quickly cut the traverse drive gain.

FIG. 7 is a block diagram showing the tracking servo abnormality detection circuit 17 of FIG. In FIG. 7, 3
6 is a traverse gain cut circuit, 48 is a voltage comparator,
Reference numeral 49 is a cycle counter, 50 is an abnormality determination unit constituting a determination device, 51 is a CAPA detection slice level, 52 is a detection width setting signal generation unit for generating a detection width setting signal d5, 53
Is a tracking on (TrON) signal, and 54 is a tracking servo abnormality detection signal.

The operation of the tracking servo abnormality detection circuit 17 thus constructed will be described with reference to FIGS. 8 and 9. FIG. 8 shows an optical disc 1 that does not have CAPA as a pre-pit address that exists in each sector.
9 is a waveform diagram of the TE signal when the information track is being followed, and FIG. 9 is a waveform diagram of the TE signal when the information track is being followed in the optical disc 1 in which CAPA is present.

The TE signal output from the FEP 14 is input to the voltage comparator 48. The other signal input to the voltage comparator 48 is the CAPA detection slice level 51. CAPA is a pre-pit address existing in each sector, and is used for optical disks such as DVD-RAM. When the tracking servo is following the optical disc 1 having a CAPA such as a DVD-RAM disc, as shown in FIG.
The TE signal greatly fluctuates in the A (abbreviation of Complementary Allo-cated Prepit Address, which is engraved on the disk medium) section.

As the fluctuation of the TE signal due to CAPA,
There are 25 fluctuations per rotation at the innermost circumference of the optical disc 1 and 59 fluctuations per rotation at the outermost circumference, and the appearance rate increases from the inner circumference toward the outer circumference. In the voltage comparator 48, by matching the CAPA detection slice level 51 with the voltage fluctuation section by the CAPA section appearing in the TE signal, the signal of only the CAPA appearance portion can be extracted as the CAPA detection signal.

In the cycle counter 49, a counter reset operation is performed by the logical sum of the CAPA detection signal output from the voltage comparator 48 and the tracking-on signal 53, and the counter value is reset to 0. In addition, the cycle counter 49
The counter value is loaded by the detection width setting signal d5, and the count result for the time set by the detection width setting signal generation unit 52 is output to the abnormality determination unit 50. In the detection width setting signal generation unit 52, an internal counter (not shown) is reset when the tracking-on signal 53 is input, and simultaneously starts counting. After that, when a count register (not shown) set for the detection width setting signal generation unit 52 is reached, the detection width setting signal d5 is output.

The abnormality determining section 50, which has received the count value from the cycle counter 49, determines from the count value whether the operation of following the information track is normal or abnormal. When the operation of following the information track is normally performed, the count value of the cycle counter 49 is reset by the CAPA detection signal. Therefore, the cycle counter 49 outputs the count value corresponding to the CAPA detection signal section width. become. However, when the information track is not followed, the track crossing signal continuously appears in the TE signal, so that the cycle counter 49 is frequently reset, and the count value does not follow the information track. It will be smaller than if it was done normally. As described above, in the abnormality determination unit 50, when an abnormality occurs in the operation of following the information track, the tracking servo abnormality detection signal 54 is output to the traverse gain cut circuit 36 to cut the traverse drive gain. work.

As described above, according to the present embodiment, the determination device for determining whether or not the tracking pull-in process performed by the tracking control is normally completed, and the traverse drive gain based on the determination result in the determination device. By having the traverse gain cut circuit 36 that cuts, the determination device detects an abnormality in the tracking pull-in processing, the tracking pull-in confirmation processing, the tracking flow detection processing, the information track following operation, and the information. When the rush of the optical pickup 2 into the mirror area where there is no data is detected and the abnormalities are detected / detected, the traverse drive gain can be cut in the traverse gain cut circuit 36. Prevents unexpected movement by following the traverse of And, to avoid damage given to the traverse moving mechanical system thus optical pickup, it is possible to perform a stable seek operation.

Further, the judging device has the mirror area judging circuit 35 for judging the occurrence of the movement of the optical pickup to the mirror area in which any recording is not permitted from the tracking error signal used in the tracking control. Since the mirror area can be determined, the mirror area can be easily determined.

Further, the traverse gain cut circuit 36
Is at least a certain time in the tracking flow detection process performed after the tracking pull-in confirmation process during the rough seek, by performing an operation based on the determination result, at least in the tracking flow detection process performed after the tracking pull-in confirmation process during the rough seek, Since the traverse drive gain is cut based on the abnormal TE signal for a fixed time, it is possible to prevent an unexpected operation due to the traverse following the abnormal TE signal.

Further, the laser reflected light from the optical disc 1 having the pre-pit address is received by the photodetector, the optical signal detected by the photodetector is converted into an electric signal, and the change of the electric signal obtained by the conversion is utilized. By doing so, it is possible to determine whether or not the tracking flow performed by the tracking control is detected in the optical disk device that performs tracking control of the data recording sequence spirally recorded on the recording surface of the optical disk 1 and focus control on the recording surface. By having a judgment device for judgment and a pre-pit address detection count circuit 17 for counting the detection of pre-pit address based on the judgment result in the judgment device, at least the pre-pit address is detected during tracking control and the number of detection times is counted. You can do this in the tracking and mirror areas. It can be detected and detects an abnormality.

(Embodiment 2) The configuration of the optical disk device according to Embodiment 2 of the present invention is the same as that of Embodiment 1, as shown in FIG.
The configuration is shown in. FIG. 10 shows the seek control circuit 1 of FIG.
It is a flowchart which shows operation | movement of 2. The difference from the conventional one, which is a feature of the present embodiment, will be described below with reference to the flowchart of FIG.

In FIG. 10, when a command (coarse seek) to a target address is received from a system controller (not shown) (S1), the seek control circuit 12 causes the traverse motor 10 in FIG. 1 to rotate. The screw shaft 11 is rotated to start traverse movement for moving the bobbin 8 (that is, the objective lens 3) in FIG. 1 to the vicinity of the target address (hereinafter referred to as traverse movement processing) (S2). Bobbin 8 near the destination address
When reaches, the traverse movement is completed (S3), and the tracking pull-in process is started (S4).

When the tracking pull-in process is completed in step S4, a tracking pull-in confirmation process is performed in order to confirm whether the tracking pull-in is correct (S5). In the tracking pull-in confirmation processing in step S5, the same processing as the processing in the tracking pull-in determination circuit 15 in FIG. 1 is executed. When the tracking pull-in determination is OK, the tracking pull-in processing is completed (S6). If the tracking pull-in determination is NG, retry processing is performed to try again to start tracking (S7). As described above, the movement processing to the target address (hereinafter referred to as seek operation) is performed.

A command (coarse seek) command to the above-mentioned destination address will be described. When a data read request is sent from the host PC to the optical disk drive device, the drive needs to move to the address where the target data exists. The host PC only issues a read request, and the seek command issues a command for the syscon (CPU mounted in the drive) to analyze the read request and move to the target address.

Here, during the tracking pull-in process in step S4, the screw shaft 11
It is desirable that the bobbin 8 is stationary because the tracking cannot be stably pulled in when the upper bobbin 8 is moving. However, immediately after the traverse movement process, the TE signal in FIG. 1 fluctuates due to the shake of the objective lens 3. As a result, the low-frequency component (not shown) of the TE signal, which is the traverse control signal, may fluctuate and the traverse may operate unexpectedly. The traverse control signal will be described below.

FIG. 11 shows a DVD as an example of an optical disc.
-Shows a schematic diagram of a RAM disk. In FIG. 11, 6
3 is a laser spot, 64 and 66 are groove tracks, and 65 is a land track. A laser beam emitted from the optical pickup 2 to the optical disc 1 in FIG. 1 is reflected by the optical disc 1 and converted into an electric signal by a photodetector (not shown) incorporated in the optical pickup 2.

When the laser spot 63 is on the groove tracks 64, 66 or the land track 65,
The electric signal is adjusted to have a certain reference voltage (hereinafter, referred to as “Vref”). When the laser spot 63 crosses the land track and the groove track, a sine waveform as shown in FIG. 12 is obtained (hereinafter, this signal is referred to as "TE signal"). FIG. 12 is a waveform diagram showing a TE signal waveform when crossing a track. In FIG. 12, 67 indicates a land track point on the land track, 68 indicates a groove track point on the groove track, and shows the case where there is a laser spot.

The optical pickup 2 is also movable in the bobbin 8 in FIG. 1 as shown in FIG. FIG. 13 is a simplified diagram of the bobbin. In FIG. 13, 8 is a bobbin, and 2 is an optical pickup. FIG. 14 is a waveform diagram showing the lens shift and the TE signal waveform. If the optical pickup 2 is located at the neutral point in the bobbin 8, the above TE
The signal is Vref as shown in the waveform (a) in FIG.
It becomes a sine waveform centered on. However, when the optical pickup 2 approaches the inner circumference or the outer circumference (hereinafter referred to as “lens shift”) due to the tracking following operation, the center point is set as shown in waveforms (b) and (c) in FIG. It varies in DC level. That is, D of the TE signal
By utilizing the change of the C signal component (low frequency component),
The same as FIG. 1 on the screw shaft 11 in FIG.
The bobbin 8 in the inside is moved according to the change in the lens shift, and the follow-up operation (traverse control) of the bobbin 8 is performed to compensate for the lens shift. Thus, the TE
The traverse control is performed by using the signal of the low frequency component of the signal as the traverse control signal.

However, in the tracking pull-in confirmation processing of step S5, an erroneous determination (tracking pull-in O
If the traverse control signal is in a fluctuating state, the traverse cannot be fixed similarly. Also,
When the bobbin 8 moves to the mirror area where no recording is allowed, the TE signal becomes undetectable,
There is a risk of making an erroneous determination in the tracking pull-in confirmation process of step S5. As a result, the traverse may behave unexpectedly. In order to prevent this, at least immediately before the start of the tracking pull-in in step S4 or immediately before the tracking pull-in confirmation processing in step S5, the traverse drive output from the traverse motor driver in FIG. 1 is performed to perform the traverse movement processing. By shutting off the gain, unexpected operation can be prevented.

As described above, according to the present embodiment, the traverse gain cut circuit 36 starts the operation based on the determination result at least before the tracking pull-in processing at the time of the rough seek, thereby at least the tracking pull-in at the time of the rough seek. Since the traverse drive gain can be cut based on the abnormal TE signal before,
It is possible to prevent an unexpected operation due to the traverse following the signal.

Further, the traverse gain cut circuit 36
Cuts the traverse drive gain based on the abnormal TE signal at least before the tracking pull-in confirmation processing performed at least after the tracking pull-in processing by starting the operation based on the determination result at least before the tracking pull-in confirmation processing performed after the tracking pull-in processing. Therefore, it is possible to prevent an unexpected operation due to the traverse following the abnormal TE signal.

Further, the traverse gain cut circuit 36
Sets the traverse drive gain to 0 when the optical pickup moves to the mirror area where no recording is allowed.
By starting the operation described above, the traverse drive gain is cut when the optical pickup moves to the mirror area, so that unexpected operation can be reliably prevented.

Further, since the tracking servo abnormality detection circuit 17 operates at least at the time of tracking flow detection performed during tracking control, it can count the pre-pit address detection at least at the time of tracking flow detection. Sometimes, it detects anomalies in the tracking and mirror areas.
Can be detected.

Further, since the tracking servo abnormality detection circuit 17 operates at least when the tracking flow is detected immediately after the tracking pull-in process, at least the pre-pit address detection can be counted when the tracking flow is detected immediately after the tracking pull-in process. When detecting the tracking flow immediately after the tracking pull-in process, it is possible to detect and detect an abnormality in the tracking or mirror area.

[0089]

As described above, according to the optical disk device of the first aspect of the present invention, the laser reflected light from the optical disk is received by the photodetector, and the optical signal detected by the photodetector is converted into an electrical signal. In an optical disc device that performs tracking control of a data recording sequence spirally recorded on the recording surface of the optical disc and focus control to the recording surface by converting and using the change of the electric signal obtained by the conversion A determination device for determining whether or not the tracking pull-in process performed in step 1 has been completed normally,
By having a traverse gain cut circuit that cuts the traverse drive gain based on the determination result in the determination device, in the determination device, tracking pull-in processing, tracking pull-in confirmation processing, tracking flow detection processing, to the information track Traverse gain can be cut in the traverse gain cut circuit when an abnormality in the tracking operation is detected, and when the optical pickup enters the mirror area where there is no information data. Therefore, it is possible to prevent an unexpected operation due to the traverse following the abnormal TE signal, avoid the damage given to the traverse moving mechanical system and the optical pickup, and obtain the advantageous effect that the stable seek operation can be performed. .

According to the optical disk device of the second aspect, in the optical disk device of the first aspect, the traverse gain cut circuit starts an operation based on the determination result at least before the tracking pull-in process at the rough seek time. Thus, the traverse drive gain can be cut based on the abnormal TE signal at least before the tracking pull-in at the time of the rough seek, so that it is possible to prevent an unexpected operation due to the traverse following the abnormal TE signal. The effect is obtained.

According to the optical disk device of the third aspect, in the optical disk device of the first aspect, the traverse gain cut circuit operates based on the determination result at least before the tracking pull-in confirmation process performed after the tracking pull-in process. By starting, at least before the tracking pull-in confirmation processing performed after the tracking pull-in processing, the traverse drive gain can be cut based on the abnormal TE signal, so that the unexpected movement due to the traverse following of the abnormal TE signal is prevented. The advantageous effect of being able to do is obtained.

According to the optical disk device of the fourth aspect, in the optical disk device of the first aspect, the determination device is used in tracking control for occurrence of movement of the optical pickup to a mirror area in which any recording is not permitted. Since the mirror area can be determined from the tracking error signal by including the mirror area determination circuit that determines from the tracking error signal, the advantageous effect that the mirror area can be easily determined is obtained.

According to the optical disk device of the fifth aspect, in the optical disk device of the fourth aspect, the traverse gain cut circuit drives the traverse when the optical pickup moves to a mirror area where no recording is permitted. By starting the operation for setting the gain to 0, the traverse drive gain is cut when the optical pickup is moved to the mirror area, so that there is an advantageous effect that an unexpected operation can be surely prevented.

According to the optical disk device of the sixth aspect, in the optical disk device of the first aspect, the traverse gain cut circuit is used for at least a predetermined time in the tracking flow detection process performed after the tracking pull-in confirmation process at the rough seek time. By performing the operation based on the determination result, the traverse drive gain is cut based on the abnormal TE signal for a certain period of time in the tracking flow detection process performed at least after the tracking pull-in confirmation process at the time of the rough seek. An advantageous effect is obtained in that it is possible to prevent an unexpected operation due to the traverse following of the signal.

According to the optical disk device of the seventh aspect, the laser reflected light from the optical disk having the pre-pit address is received by the photodetector, the optical signal detected by the photodetector is converted into an electric signal, and the optical signal is converted. Tracking performed by tracking control in an optical disk device that performs tracking control of a data recording row spirally recorded on the recording surface of the optical disk and focus control on the recording surface by using the change of the obtained electric signal At least tracking control is provided by including a determination device that determines whether or not a flow is detected, and a pre-pit address detection counting circuit (tracking flow detection circuit) that counts pre-pit address detection based on the determination result of the determination device. Detect the pre-pit address inside,
Since it is possible to count the number of times of detection, it is possible to obtain an advantageous effect that it is possible to detect and detect an abnormality in tracking or a mirror area.

According to the optical disk device of the eighth aspect, in the optical disk device of the seventh aspect, the pre-pit address detection count circuit (tracking flow detection circuit) is at least a tracking flow detection performed during tracking control. Since the pre-pit address detection can be counted at least at the time of detecting the tracking flow by operating occasionally, it is possible to obtain the advantageous effect of being able to detect and detect an abnormality in the tracking or the mirror area at the time of detecting the tracking flow.

According to the optical disk device of the ninth aspect, in the optical disk device of the seventh aspect, the pre-pit address detection count circuit (tracking flow detection circuit) is at least when the tracking flow is detected immediately after the tracking pull-in process. By operating, the pre-pit address detection can be counted at least when the tracking flow is detected immediately after the tracking pull-in process. The advantageous effect that it can be obtained.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing a tracking pull-in determination circuit of FIG.

FIG. 3 is a block diagram showing a mirror area determination circuit of FIG.

FIG. 4 is a waveform diagram showing a TE signal in a data area.

FIG. 5 is a waveform diagram showing a TE signal in the mirror area.

6 is a block diagram showing the tracking flow detection circuit of FIG.

7 is a block diagram showing the tracking servo abnormality detection circuit of FIG.

FIG. 8 is a waveform diagram of a TE signal when following an information track.

FIG. 9 is a waveform diagram of a TE signal when following an information track.

10 is a flowchart showing the operation of the seek control circuit of FIG.

FIG. 11 is a schematic diagram of a DVD-RAM disc.

FIG. 12 is a waveform diagram showing a TE signal waveform when crossing a track.

FIG. 13 is a simplified diagram of a bobbin.

FIG. 14 is a waveform diagram showing a lens shift and a TE signal waveform.

FIG. 15 is a configuration diagram showing a conventional optical disc device.

16 is a block diagram showing the tracking servo system of FIG.

17 is a block diagram showing the tracking pull-in determination circuit of FIG.

FIG. 18 is a block diagram showing the tracking flow detection circuit of FIG.

[Explanation of symbols]

1 optical disc 2 optical pickup 3 Objective lens 4 Tracking actuator driver 5 Tracking servo circuit 6 Focus driver 7 Focus servo circuit 8 bobbins 9 Traverse motor 10 Traverse motor driver 11 screw shaft 12 seek control circuit 13 Spindle motor 14 Front-end processor (FEP) 15 Tracking pull-in determination circuit 16 Tracking flow detection circuit 17 Tracking servo error detection circuit 18 Tracking pull-in determination circuit 19 Tracking flow detection circuit 20 Tracking equalizer 21 Tracking coil control amplifier 22 Tracking coil 23 Equalizer for motor control 24 Motor control amplifier 25 track jump counter 26, 38 Comparator 27 Repeat routine section 28 Judgment part 29 Tracking pull-in processing start signal 30 Confirmation time width setting register 31 Normal jump number setting register 32, 43 Tracking flow detection time setting register 33, 44 Normal tracking flow number setting register 34 Tracking flow detection start signal 35 Mirror area determination circuit 36 Traverse gain cut circuit 37 Pull-in error signal 39 TE signal 40 Mirror judgment reference signal 42 Tracking flow detection start signal 45 Return routine section 46 Judgment start end command section 47 switch 48 voltage comparator 49 cycle counter 50 Abnormality judgment section 51 CAPA detection slice level 52 Detection width setting signal generator 53 TrON signal 54 Tracking servo error detection signal 63 laser spot 64, 66 groove track 65 Land Truck 67 Land Track Point 68 Groove Track Point

Claims (9)

[Claims] 1. A laser beam reflected from an optical disc is received by a photodetector, an optical signal detected by the photodetector is converted into an electric signal, and a change in the electric signal obtained by the conversion is utilized to obtain: In an optical disk device that performs tracking control of a data recording row spirally recorded on the recording surface of an optical disk and focus control on the recording surface, it is determined whether or not the tracking pull-in processing performed by the tracking control is normally completed. An optical disc device comprising: a determination device for determination, and a traverse gain cut circuit for cutting a traverse drive gain based on a determination result in the determination device. 2. The optical disc apparatus according to claim 1, wherein the traverse gain cut circuit starts an operation based on the determination result at least before the tracking pull-in process at the time of rough seek. 3. The optical disk apparatus according to claim 1, wherein the traverse gain cut circuit starts an operation based on the determination result at least before the tracking pull-in confirmation processing performed after the tracking pull-in processing. 4. The optical disc according to claim 1, wherein the determination device has a mirror area determination circuit for determining occurrence of movement of the optical pickup to the mirror area from a tracking error signal used in tracking control. apparatus. 5. The optical disk apparatus according to claim 4, wherein the traverse gain cut circuit starts an operation for setting a traverse drive gain to 0 when an optical pickup moves to a mirror area. 6. The traverse gain cut circuit, at least for a predetermined time in a tracking flow detection process performed after a tracking pull-in confirmation process at the time of rough seek,
The optical disk device according to claim 1, wherein an operation is performed based on the determination result. 7. A laser beam reflected from an optical disk having a prepit address is received by a photodetector, an optical signal detected by the photodetector is converted into an electric signal, and a change in the electric signal obtained by the conversion is converted. By using it, whether or not the tracking flow carried out by the tracking control is detected in the optical disk device which performs tracking control of the data recording sequence spirally recorded on the recording surface of the optical disk and focus control on the recording surface. An optical disk device comprising: a judgment device for judging whether or not the prepit address is detected based on a judgment result of the judgment device. 8. The optical disk device according to claim 7, wherein the pre-pit address detection count circuit operates at least when a tracking flow is detected during the tracking control. 9. The optical disk apparatus according to claim 7, wherein the pre-pit address detection count circuit operates at least when a tracking flow is detected immediately after the tracking pull-in process.