KR100257621B1 - Apparatus for jumping track of optical disk system and its controlling method - Google Patents

Abstract

PURPOSE: A method for controlling a track jump of an optical disk system and a controlling method thereof are provided to exactly perform a track jump for data searching, and to compensate a track count pulse signal used when the track jump is carried out. CONSTITUTION: An optical disk system detects a track count pulse in accordance with a track movement of an optical pickup device. The system detects a track moving time of the optical pickup device. If the track count pulse is not detected within a set time, the system track-moves the optical pickup device during the set time relating to a unit track. If the track count pulse is detected within the set time, the system completes the track movement as detecting the pulse, simultaneously. In the step of track-moving of the optical pickup device, a forward voltage is applied to the optical pickup device during the first set time, and a backward voltage is applied during the second set time.

Description

Track jumper and control method of optical disc system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a track jumping apparatus and a control method thereof for an optical disc system, and more particularly, to a track jumping apparatus for performing a track jumping operation for data search and a control method thereof.

The optical disc system tracks the information track on which data is recorded on the disc and reads out the data recorded on the track. Therefore, after the data recorded in one track is read, 1 track jump is performed to read the data recorded in the next track. If the track is located at a short distance, 10 track jump is performed. When track movement located at a distance is to be performed, M track movement by driving the slide motor is performed.

That is, the optical disc system performs a track jump operation for searching for desired data in order to read the desired data among the data recorded on the disk. Adjust the sub control. However, even after 10 track movements or after M track movements, a one track jump operation is required in which the optical pickup device is positioned at the center of the track on which the data to be reproduced is recorded, so the operation of the one track jump requires very accuracy.

Furthermore, in the case of a digital video disc which does not perform continuous renewal of recorded data as in a compact disc but selectively performs data playback after moving a track to a place where necessary data is located, operations for searching for desired data occur very frequently. As a result, the operation of one track jump requires very high accuracy.

1 is a block diagram showing a general optical disc reproducing system.

Beams emitted from the laser diode 1 included in the optical pickup apparatus 10 of the optical disc reproducing system are divided into three beams through the diffraction grating 2. The beam split into three beams in the diffraction grating 2 passes through a collimator lens 4 which makes a parallel beam via a beam splitter 3. Then, an optical lens 6 passes through an object lens 5 that focuses a beam spot on a pit in which information is recorded.

Through such a path, the beam modulated by the information carrier recorded on the information recording surface of the optical disc 6 is reflected along the same path back to the objective lens, the collimating lens, and the beam splitter. The path is changed in the beam splitter and is collected by a sensor lens 7, and the focused beam is incident to an optical detector 8.

In this case, the photodetector 8 is located at the center of the light receiving unit (A, B, C, D) for receiving the main beam is divided into four. The light receiving units E and F for receiving the auxiliary beam are positioned above and below the main beam.

The electrical signal output from the photodetector 8 of the pickup apparatus 10 configured as described above is a reproduction signal processor for performing predetermined signal processing and amplification so as to be used as a basic signal for tracking and focusing control and information reproduction ( 11) is applied. The tracking error signals A + C- (B + D) and focusing error signals A + C- (B + D) output from the reproduction signal processing unit 11 are input to the servo unit 12, Servo control is performed according to the tracking of the optical pickup device 10 and the adjustment of the focusing actuator 9. That is, the tracking jump of the optical pickup device 10 is made by adjusting the tracking actuator 9 of the optical pickup device 10 within a small range such as 1 track jump or 10 track jump.

In addition, the electrical signal (A + B + C + D) output from the photodetector 8 of the pickup device 10 is output by performing a process of predetermined signal compensation and filtering for reproduction. At this time, after the signal is processed until the output signal is displayed in the digital signal processing unit 13, it is output to the display device, the user is watching the desired image.

That is, the optical pickup apparatus 10 emits the laser 1 to irradiate the disk 6, and receives the optical signal reflected from the disk 6 by the photodetector 8 to reproduce the disk. Therefore, the spot of the laser 1 irradiated from the optical pickup apparatus 10 accurately tracks the track of the disk 6 on which the information is recorded, and also includes an error that is included in the data to be read only when the focus of the track is correctly adjusted. The signal is minimized.

The optical pickup apparatus 10 having such a configuration is mounted on the slide motor 14, and the slide motor 14 is driven when the number of tracks to be moved by the optical pickup apparatus 10 is large, such as M track movement. The track movement of the optical pickup device 10 is made. The microcomputer 15 performs an operation of managing the system as a whole according to the reproduction of the disc 6.

Next, an operation process during one track jump operation according to the prior art will be described with reference to FIG. 2.

3 shows an output waveform diagram generated during the operation of the track jump.

The microcomputer 15 applies a control command to the servo unit 12 to output the voltage set for one track movement. The servo unit 12 applies a predetermined amount of forward voltage to the tracking actuator 9 of the optical pickup device 10 (step 101). The forward voltage according to the 101st step is supplied to the tracking actuator 9.

That is, after the forward voltage is applied in step 101, the reproduction signal processing unit 11 is based on the optical signal received by the photodetector 8 of the optical pickup apparatus 10, as shown in FIG. The same tracking error signals A + C- (B + D) and reproduction high frequency signals A + B + C + D as shown in FIG. 3 (b) are output. The signal which detected the tracking error signal detected at this time as a pulse signal is a 3rd (c) figure, and the signal which detected the said reproduction signal as a pulse signal is a 3rd (d) figure.

In this way, after the predetermined blind time in step 103 has elapsed immediately after the tracking actuator voltage is applied, it is monitored whether the rising edge of the track count pulse in FIG. 3 (e) is detected (step 105). The track count pulse according to step 105 is a signal detected while counting the number of tracks to be moved, and is generated from a point where 1/2 position of the detected tracking error signal and 1/2 position of the reproduction high frequency signal meet. Therefore, the rising edge point of the track count pulse means that the optical pickup device 10 is passing one half of the track.

When the rising edge of the track count pulse in step 105 is detected, the servo unit 12 converts the forward voltage applied to the tracking actuator 9 of the optical pickup device 10 to the reverse voltage and applies the reverse voltage. (Step 107). That is, the step 107 is to decelerate the moving speed of the tracking actuator 9 by applying a reverse voltage to the tracking actuator 9 at the track count rising edge, which is a point passing half of the track.

The reverse voltage of the tracking actuator 9 according to the step 107 is applied during the set break time, and if the reverse voltage is applied during this time, the track actuator 9 becomes almost "0" and the movement of one track is completed. (Step 109). Thereafter, the tracking servo is operated normally to resume the operation of reading data while tracking the recording track on the disc 6 again (step 111).

That is, in the conventional one track jump movement, the positive voltage is continuously applied to the tracking actuator 9 until the rising edge point of the track count pulse is detected, thereby accelerating the tracking actuator 9, and the rising of the track count pulse. After the edge point is detected, the reverse direction voltage is applied to the tracking actuator 9 to decelerate the tracking actuator 9.

Thus, in the conventional one track jump method, when a track count pulse is not detected, there is a problem in that one track jump is not performed while only a positive voltage is continuously applied to the tracking actuator 9. In addition, in the conventional one-track jump method, when the track count pulse is detected too late, the tracking actuator becomes more accelerated than the normal state, whereas the reverse voltage application time for decelerating it is performed during the predetermined break time. The track slipping problem occurred without the normal track jump.

Next, FIG. 4 is an operation flowchart according to the 10 track jump movement.

The microcomputer 15 applies a control command to the servo unit 12 to output a voltage set for 10-track movement. The servo unit 12 applies a predetermined amount of forward voltage to the tracking actuator 9 of the optical pickup device 10 (step 201). The forward voltage in step 201 is supplied to the tracking actuator 9.

That is, based on the optical signal received by the photodetector 8 of the optical pickup apparatus 10 after the application of the forward voltage in step 201, the reproduction signal processing unit 11 is shown in FIG. 3 (a). The same tracking error signals A + C- (B + D) and reproduction high frequency signals A + B + C + D as shown in FIG. 3 (b) are output. After waiting for the set blade time until such a signal is output (step 203), it is monitored whether five track count pulses are detected based on the output tracking error signal and the ashing high frequency signal (step 205). step). The forward voltage is continuously applied to the tracking actuator 9 until five track count pulses are detected.

When five track count pulses are detected in step 205, the servo unit 12 applies a reverse voltage to the tracking actuator 9, and while the reverse voltage is applied, the detected track count pulse period is referred to. It is monitored whether it is longer than the period (step 209).

In the step 209, the tracking actuator 9 is accelerated while the forward voltage is applied to the tracking actuator 9 until the five track count pulses are detected, and then the tracking actuator 9 is applied while the reverse voltage is applied. ) Detects when the speed of nearly "0" is reached since the cycle of the track count pulse detected gradually decreases gradually.

When the track count pulse detected by the step 209 is longer than the reference period, the microprocessor 15 performs reproduction of the disc while operating the tracking servo of the servo unit 12 (step 211).

That is, in the conventional 10-track jump method, a forward voltage is applied while a 5 track count pulse is detected, and a reverse track voltage is applied until the detected track count pulse period is longer than the reference period to perform 10 track jump. have.

Therefore, the conventional 10-track jump method counts five track count pulses, checks the period of the track count pulses, and so on, depending on the accuracy of the track count pulses being counted. There is a problem that track slip occurs.

In addition, the conventional 10-track jump method has a case in which the operation of applying the reverse voltage continuously occurs even when the moving direction of the tracking actuator is changed while the reverse voltage is applied, thereby generating track slipping.

Next, FIG. 5 is a flowchart illustrating a conventional M track jump operation.

After the control of the servo unit 12 turns off the operation of the tracking servo to maintain the current track, the microcomputer 15 applies a control command for instructing the M track movement to the servo unit 12. The servo unit 12 drives the slide motor 14 on which the optical pickup device 10 is mounted in the forward direction (step 301).

Immediately after driving for the track movement of the optical pickup apparatus 10 in step 301, the predetermined bladder time is waited for (step 303), and thereafter, in the photodetector 8 of the optical pickup apparatus 10, The number of tracks to be moved is counted based on the detected signal (step 305). The track movement of the optical pickup apparatus 10 by the driving of the slide motor 14 continues until the number of tracks detected in step 305 reaches the number of tracks M to be moved.

When M track count pulses are detected in step 305, the microcomputer 15 applies a control signal to the servo unit 12 to stop driving of the slide motor 14, and the servo unit 12 The drive of the slide motor 14 is stopped by this signal. The servo unit 12 turns on the tracking servo to control the optical pickup device 10 to read data while normally tracking the recording track of the disc 6 (step 307).

That is, the conventional M track jump method controls the track movement of the optical pickup apparatus by driving the slide motor until track count pulses are detected by the number of tracks to be moved. However, immediately after the desired number of tracks is detected, the stop position of the slide motor is out of the desired position due to the inertia that is moved even when the driving of the slide motor is stopped. That is, track slippage is generated.

In addition, since the conventional M track jump method is detected by counting the number of tracks to which the detection up to the number of target tracks is moved, there is a problem of causing track slippage when the number of tracks to be counted is not correct.

In the above description, since the conventional track jump method tends to depend on the track count pulse to be detected, there is no method that can prevent the occurrence of track slippage when the detected track count pulse is not accurate. In particular, when there are defects or scratches on the disc, the track actuator may not be generated normally, so that the tracking actuator remains too accelerated or less accelerated until the rising edge of the track count pulse is detected. There is a problem that can not suppress the occurrence of track slip caused by. In addition, in the conventional track jump method, the influence depending on the acceleration and deceleration characteristics of the tracking actuator is too large.

Accordingly, an object of the present invention is to provide a track jump control apparatus and an control method thereof for an optical disk system capable of accurately performing track jump for data search.

Another object of the present invention is to provide an apparatus and method for controlling a track jump of an optical disc system capable of compensating for a track count pulse signal used when performing a track jump.

1 is a block diagram showing a general optical disc reproducing system.

2 is an operation process diagram during a one-track jump operation according to the prior art.

3 is an output waveform diagram generated during the operation of a conventional track jump.

4 is an operation flowchart according to a 10-track jump movement.

5 is a flowchart according to a conventional M track jump operation.

6 is an operation flowchart for controlling the operation of the one track jump according to the present invention.

7 is a waveform diagram that is output while one track jump operation is performed.

8 is a flow chart of operation for 2N track jumps in accordance with the present invention.

9 is a waveform diagram output during a 2N track jump operation.

10 is a block diagram of an M track jumper.

11 is a timing diagram when performing M track jump of the present invention.

* Explanation of symbols for main parts of the drawings

30: control unit 32, 34: noise removing unit

36: latch 38: direction detection unit

40, 42: Signal selector 44: Speed detection cycle count

46: number of jump tracks 48: track jump control unit

50: reference speed generator

A one-track jump method of an optical disc system according to the present invention comprises the steps of: detecting a track count pulse according to a track movement of an optical pickup apparatus; Detecting a track movement time of the optical pickup apparatus; And when the track count pulse is not detected within the set time, track moving the optical pickup device for the set time for the unit track, and if the track count pulse is detected within the set time, the track movement is terminated at the same time as the pulse detection. do.

An N track jump method of an optical disc reproducing system according to the present invention includes the steps of: accelerating a moving speed of a pickup up to a predetermined period of a target number of tracks; Decelerating a moving speed of the pickup when a predetermined section of the target track number is detected; Monitoring whether the moving direction of the pickup changes while the moving speed of the pickup is decelerated, and simultaneously monitoring whether the target track number is detected; Stopping the movement of the pickup when the direction of movement of the pickup is changed or the target track number is detected.

An M track jumping apparatus of an optical disc reproducing system according to the present invention comprises: direction / speed detection means for detecting a moving direction and a speed of a pickup; A jump track number counter for counting the number of jump tracks of the pickup; Reference speed generating means for generating a reference speed according to the number of jumped tracks; Pickup driving means for accelerating the speed of pickup until a predetermined number of tracks is detected in said jump track number counter, and decelerating the speed of pickup after a predetermined number of tracks is detected; And track jump control means for controlling the pickup driving means so that a difference signal between the speed detecting means and the reference speed generating means is not generated.

In the one-track jump method of the present invention, when the track count pulse is normally detected, the track movement of the optical pickup apparatus is performed by the forward voltage until the rising edge of the track count pulse. When the reverse voltage is applied to the falling edge of the track count pulse or when the falling edge of the track count pulse is not detected within the set time, the reverse voltage is cut off when the set time elapses.

In addition, when the track count pulse is not normally detected, the one-track jump method of the present invention performs the track movement of the optical pickup device by the positive voltage for a predetermined time, and reverses the voltage in the reverse direction as much as the positive time is applied. It is characterized by applying.

Hereinafter, with reference to the accompanying drawings will be described in detail a track jumping device and a control method of the optical disc system according to the present invention. The necessary hardware configuration will be described with reference to FIG.

6 is an operation flowchart for controlling the operation of the one track jump according to the present invention. 7 shows a waveform diagram that is output while one track jump operation is performed.

First, since the slide motor 14 is not driven at the time of one track jump movement, the microcomputer 15 turns off the slide servo. Then, the servo actuator 12 applies the positive voltage to the tracking actuator 9 of the optical pickup device 10 (T1 section in FIG. 7 (d)), and simultaneously the positive voltage is applied to the tracking actuator 9. The acceleration time at which the acceleration in (9) is performed is counted (step 401).

After the forward voltage according to the step 401 is applied, a predetermined blind time is provided to prevent a malfunction due to an incorrect track count pulse (step 403).

When the set blade time has elapsed, a time (current acceleration time) when the forward voltage is applied is detected, and it is compared whether the current acceleration time is larger than the reference acceleration time for the set one track jump (step 405).

By comparing the step 405, it is determined whether the rising edge point of the track count pulse is detected when the current acceleration time is smaller than the reference acceleration time (step 407). During the normal track jump, since the track count pulse is generated before and after passing through the center of the track, if the track count pulse is detected within the reference acceleration time, it will be determined that the normal track jump operation is performed in this case.

When the rising edge of the track count pulse in step 407 is detected (Fig. 7 (b)), the microcomputer 15 applies the reverse voltage to the tracking actuator 9 from this time (Fig. 7 (d)). T2 interval in degrees). As the reverse voltage is applied, the tracking actuator 9 begins to decelerate, and counts the deceleration time of the tracking actuator 9 from the deceleration start point (step 409).

Comparing whether the deceleration time of the tracking actuator 9 is greater than the set reference deceleration time by performing the step 409 (step 411), the falling edge of the track count pulse is detected until the deceleration time of the tracking actuator 9 is greater than the reference deceleration time. It is monitored (step 413).

That is, if the falling edge of the track count pulse is detected while the current deceleration time is smaller than the set reference deceleration time, the speed is close to “0”. Therefore, the track servo operation is completed and the tracking servo is operated normally. The operation for playing the disc is started (step 415).

However, if the falling edge of the track count pulse is not detected until the current deceleration time is equal to the set deceleration time in step 411, the microcomputer 15 turns on the tracking servo according to step 415 while ending the deceleration time. .

That is, when the deceleration section of the tracking actuator 9 is longer than the set time, the tracking servo is turned on regardless of the presence or absence of the detection of the falling edge of the track count pulse.

In addition, when the rising edge of the track count pulse is not detected within the set reference acceleration time in step 405, the acceleration section is terminated by applying a forward voltage to the tracking actuator at the end of the set reference acceleration time. At this time, a voltage in the reverse direction for deceleration of the tracking actuator 9 is applied, and at the same time, the deceleration time is counted (step 417).

The deceleration time of the tracking actuator 9 is also finished at the point where the current deceleration time is continuously counted and becomes equal to the reference acceleration time (step 419).

In other words, when the acceleration period of the tracking actuator 9 becomes longer than the set acceleration time, the acceleration time is terminated at the point coinciding with the reference acceleration time regardless of the presence or absence of the detection of the rising edge of the track count pulse. After applying the deceleration time, the tracking servo is turned on.

Next, FIG. 8 is an operation flowchart for 2N track jump according to the present invention. 9 shows a waveform diagram output during the 2N track jump operation.

Since the slide motor 14 is not driven during the 2N track jump movement, the microcomputer 15 turns off the slide servo. Then, the servo unit 12 applies a positive voltage to the tracking actuator 9 of the optical pickup device 10 (step 501).

After the forward voltage of step 501 is applied, a predetermined blind time is provided to prevent a malfunction due to an incorrect track count pulse (step 503).

That is, after the forward voltage is applied in step 501, the reproduction signal processing unit 11 outputs a tracking error signal based on the optical signal received by the photodetector 8 of the optical pickup device 10, and the tracking error. Based on the signal, a pulse signal as shown in Fig. 9A is output. Then, based on the reproduction high frequency signal output from the reproduction signal processing section 11, a pulse signal as shown in Fig. 9B is output.

On the other hand, it is monitored whether N track count pulses are detected based on the pulse signal detected from the tracking error signal and the reproduction high frequency signal (step 505). A forward voltage is continuously applied to the tracking actuator 9 until N track count pulses are detected.

When N track count pulses are detected in step 205, the servo unit 12 applies a reverse voltage to the tracking actuator 9 (step 507), and while the reverse voltage is applied, the tracking actuator ( It is monitored whether the traveling direction of 9) is changed (step 509).

If the traveling direction of the tracking actuator 9 in the step 509 is not changed (Fig. 9 (c)), the number of track count pulses to be detected is continuously counted, and the detected track count pulses are the ninth (d). As shown in Fig. 2 (step 511), it is judged that the deceleration of the tracking actuator has been sufficiently decremented, and the reproducing operation of the disc is performed while turning on the tracking servo (step 513).

9 (a) and 9 (b) are pulse error signals for the tracking error signal and the reproduction high frequency signal detected from the optical pickup device 10, and FIG. 9 (c) shows the tracking actuator 9 until the deceleration period ends. ) Does not change the direction of travel. Fig. 9 (d) shows that the deceleration section applied to the tracking actuator 9 ends when the track count pulse signal is normally detected for 2N (Fig. 9 (e)).

On the other hand, the change in the traveling direction of the tracking actuator 9 in the step 509 means that the deceleration of the actuator is sufficient, and it is the moment to move backward from now on. The detection of the actuator traveling direction is detected as a phase of the tracking error signal and the reproduction high frequency signal.

Therefore, the operation of detecting the track count pulse up to 2N at step 511 at the time when the moving direction of the tracking actuator 9 changes in step 509 is omitted, and the tracking servo is controlled to the normal state immediately. That is, in step 509, the direction of the tracking actuator 9 is changed, and at the same time, the tracking servo in step 513 is turned on.

9 (f) and 9 (g) are pulse signals for the tracking error signal and the reproduction high frequency signal detected from the optical pickup device 10, and FIG. 9 (h) shows the progress of the tracking actuator 9 during the deceleration period. Indicates when the direction is changed. Therefore, as the traveling direction of the tracking actuator 9 changes, the deceleration voltage applied to the tracking actuator 9 is cut off. As shown in the second half of FIG. 9 (f) and the ninth (g), the shifting direction of the actuator can be detected by the phase change of the tracking error signal and the reproduction high frequency signal. Therefore, in this case, 2N track count pulses may not be detected.

Next, FIG. 10 shows a block diagram of the M track jumper.

The M track jumper according to the present invention inputs a pulse signal generated from a tracking error signal, removes a noise signal included in the pulse signal, and a pulse signal generated from a reproduction high frequency signal. A second noise canceller 34 for removing a noisy signal included in the pulse signal, and an output signal from the first noise canceller 32 and the second noise canceller 34 and input two signals. And a direction detecting unit 38 for detecting a traveling direction of the current optical pickup apparatus by comparing the phases of the optical pickup devices.

The M track jumper of the present invention uses the output signal of the first and second noise canceling units 32 and 34 and the latch 36 to delay and output the reproduction high frequency pulse signal using the tracking error pulse signal as a clock signal. First and second signal selectors 40 and 42 for selecting one of the output signals, and a speed detection cycle counter 44 for detecting the current speed by detecting the output period of the first signal selector 40. It includes.

The M track jumper according to the present invention includes a jump track number counter 46 that counts the number of jump tracks based on the output signal of the second signal selector 42, and an output value of the jump track number counter 46. Reference speed generator 50 for generating a reference speed according to the.

In addition, the M track jumper of the present invention proceeds according to the track jump direction of the current optical pickup device detected by the direction detecting unit 38 and the track jump of the current optical pickup device detected by the speed detection period counter 44. A track jump control unit for inputting a speed and a reference speed generated by the reference speed generator 50 and controlling the driving speed of the slide motor and the driving speed of the tracking actuator so that the difference signal between the two speeds is “0” (48). And M track jumper of the present invention further comprises a control unit 30 for controlling the system as a whole.

A detailed description will be given with reference to the timing chart to which the M track jump operation of the present invention according to the above configuration is attached.

11 is a timing diagram when performing the M track jump of the present invention.

First, under the control of the track jump controller 48, as shown in FIG. 11A, a slide motor driving signal having a length set in the section of S1 is outputted to guide and move the optical pickup apparatus. In addition, a driving signal is applied to the tracking actuator of the set length in the section of S2 to move the tracking actuator in the forward direction. Of course, the slide motor is being driven even in the S2 section.

As the slide motor is driven and the tracking actuator is driven as described above, a signal reflected from the disk from the optical pickup apparatus is detected, and a reproduction high frequency signal and a tracking error signal are generated based on the detected signal.

The first and second noise canceling units 32 and 34 remove noise signals included in the pulse signal generated from the reproduced high frequency signal and the tracking error signal. That is, the first and second noise canceling units 32 and 34 output the pulse signal obtained from the pure high frequency signal and the pulse signal obtained from the tracking error signal after the unnecessary noise signal is removed. Fig. 11C shows a pulse signal obtained from the tracking error signal.

The direction detecting unit 38 detects the phase difference of the reproduction high frequency pulse signal or the tracking error pulse signal under the control of the control unit 30, and detects the track jump direction of the current optical pickup apparatus.

The speed detection period counter 44 detects the pulse period of the tracking error pulse signal under the control of the control unit 30 to detect the track jump speed of the current optical pickup apparatus. Therefore, the speed of the optical pickup device is accelerated from the S2 section, and the period of the tracking error pulse signal detected is faster.

Similarly, the jump track number counter 46 also counts the number of jumped tracks of the current optical pickup apparatus under the control of the control unit 30. Therefore, the period of the track count pulse signal, which is an output signal of the jump track number counter 46, from the S2 section is also accelerated.

The track jump controller 48 controls the driving speed of the tracking actuator and the slide motor such that the speed of the tracking actuator has a certain period in the section S3. The speed control of the tracking actuator controls the difference between the output signal of the reference speed generator 50 and the output signal of the speed detection period counter 44 so that the pickup device moves at the constant speed during the S3 period. This operation continues until the number of jumped tracks detected by the jump track number counter 46 reaches a predetermined value.

That is, the optical pickup device is moved in the direction detected by the direction detecting unit 38, where the track jump controller 48 detects the reference speed generated by the reference speed generator 50 and the speed detecting period counter 44. The tracking actuator is controlled so that the difference in speed becomes zero.

After the S3 section continues until the track count pulse detected by the jump track number counter 46 is counted by a predetermined value, the slide motor is stopped when the desired track count pulse is counted by the jump track number counter 46. To apply the brake pulse voltage to the slide motor during the period of S40. The tracking actuator measures the period of the tracking error pulse signal input to the speed detection period counter 44 in the section of S40 so that the tracking error pulse signal period matches the period of the reference speed generated by the reference speed generator 50. Controlled.

Next, in the S41 section, a signal is applied only to the tracking actuator while the voltage applied to the slide motor is cut off, and at this time, the signal applied to the tracking actuator is detected by the speed detection cycle counter 44 and the reference speed generator 50. ) To make the same occurrence period of

The track counter value detected by the jump track number counter 46 continues to increase until the S41 section elapses, and when the number of tracks corresponding to the M tracks is detected, the track jump controller 48 stops the brake actuator during the S42 section. Is applied. At this time, the reference speed of the reference speed generator 50 is changed so that the speed of the tracking actuator becomes zero by the brake voltage.

And during S5, the tracking servo is settled faster by making the tracking gain higher than normal. The slide servo remains off during the S5 section. Thereafter, the slide servo is turned on, and the gain of the tracking servo is switched to the normal state, thereby controlling normal disc reproduction.

As described above, the present invention makes the track jump operation driven for data search accurate and stable. In particular, when the defect or scratch is present on the disc, the track jumping can be made accurate and stable even while passing through the portion. Since 2N track jumping can be performed, the number of tracks to be moved is 2, 4, 6... … With 2N lights, there is an advantage that the desired track jump can be performed at a time. In addition, the M track jump has an advantage of performing a quick and accurate jump by controlling the track jump of the optical pickup apparatus using the track jumping speed.

Claims (8)

Detecting a track count pulse according to the track movement of the optical pickup apparatus; Detecting a track movement time of the optical pickup apparatus; And when the track count pulse is not detected within the set time, the optical pickup device tracks for the set time for the unit track, and if the track count pulse is detected within the set time, the track movement is terminated at the same time as the pulse detection. A track jump control method for an optical disc system. The method of claim 1, wherein the track movement step of the optical pickup device comprises applying a forward voltage to the optical pickup device for a first set time and applying a reverse voltage to the optical pickup device for a second set time. A track jump control method for an optical disc system. Accelerating the moving speed of the pickup while monitoring the rising edge detection of the track count pulse within the reference acceleration time; If the rising edge of the track count pulse is detected within the reference acceleration time, decelerating the movement speed of the pickup and monitoring the detection of the falling edge of the track count pulse within the reference acceleration time; If the rising edge of the track count pulse is not detected within the reference acceleration time, ending the acceleration section of the pickup and performing the deceleration section by the acceleration section; Stopping the movement of the pickup when the falling edge of the track count pulse is detected or the reference deceleration time is reached within the reference deceleration time; Accelerating a moving speed of the pickup up to a predetermined period of the target track number; Decelerating a moving speed of the pickup when a predetermined section of the target track number is detected; Monitoring whether the moving direction of the pickup changes while the moving speed of the pickup is decelerated, and simultaneously monitoring whether the target track number is detected; Stopping the movement of the pickup when the direction of movement of the pickup is changed or the number of target tracks is detected. 5. The track jump control method for an optical disc system according to claim 4, wherein the section in which the movement speed of the pickup is accelerated is made until half of the target track number is detected. Direction / speed detection means for detecting a moving direction and a speed of the pickup; A jump track number counter for counting the number of jump tracks of the pickup; Reference speed generating means for generating a reference speed according to the number of jumped tracks; Pickup driving means for accelerating the speed of pickup until a predetermined number of tracks is detected in said jump track number counter, and decelerating the speed of pickup after a predetermined number of tracks is detected; And track jump control means for controlling the pickup driving means so that a difference signal between the speed detecting means and the reference speed generating means is not generated. 7. The track jump control apparatus for an optical disc system according to claim 6, wherein the output signal of the reference speed generator generated in the acceleration section and the deceleration section of said pickup driving means has a different value. 8. The track jump control method for an optical disc system according to claim 7, wherein the speed / direction detecting means of the pickup detects the speed and direction based on a reproduction high frequency signal or a tracking error signal.

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