JPH09147382A - Disk player - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk player capable of playing without generating a sound-dropout even though a scratch is present on a disk. SOLUTION: When a scratch is detected on a compact disk 11, the input of a tracking servo control part 19b is changed over from the side of the tracking error detecting circuit of an RF amplifier 15 to the side of a DC hold circuit 26 by a changeover circuit 25. Next, the pickup hold signal from the DC hold circuit 26 is inputted to the tracking servo control part 19b, which outputs a tracking servo signal and a tracking correcting circuit 24 prepares a tracking correction signal based on the scratch detection signal DFS from a defect circuit of the RF amplifier 15. Moreover, the tracking correction signal and the tracking servo control signal are added in an adding circuit 27 to drive a tracking actuator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc player, and more particularly to a disc player capable of preventing skipping due to scratches on the disc.

[0002]

2. Description of the Related Art In a disc player such as a CD and a video disc, a beam spot of a laser emitted from an optical pickup is focused on a disc signal surface by a focusing servo, and a pit row is formed according to the rotation of the disc by a tracking servo. While properly tracing the (track), the reflected beam is photoelectrically converted by a 4-division photodiode, etc.
After the signal is created, the digital signal processing circuit performs data demodulation, error detection / correction, and other processing to reproduce subcode data and audio data. By the way, in the disc player, when the disc has scratches or dust, a tracking error occurs there, and accurate tracking control cannot be performed, resulting in sound skipping. In order to prevent this sound skip, conventionally, a detection circuit for detecting scratches or dust on the disk is provided, and when the scratches or dust are detected, the DC level of the tracking error signal is held (DC hold) to prevent scratches or dust. It keeps holding while dust is detected, and returns to normal tracking servo when scratches and dust are no longer detected.

[0003]

However, in the conventional disc player such as the CD or the video disc as described above, the DC level is held when the scratch or dust is detected, so that the pickup has the DC level. It remains stopped at the corresponding position. However, even though the pickup was stopped, the disc itself continued to rotate, and when scratches and dust were not detected, the track continued spiraling from the inside to the outside, so On the other hand, it means that they are moving outward (Fig. 8
reference). Therefore, at this time, there is a problem that a track is displaced and a sound skip occurs. From the above, an object of the present invention is to provide a disc player capable of playing without causing skipping even if the disc is scratched.

[0004]

According to the first aspect of the present invention,
A pickup that detects the signal recorded on the disc,
A tracking error detection circuit that creates a tracking error signal based on a detection signal from the pickup; a pickup holding circuit that inputs the tracking error signal from the tracking error detection circuit and outputs a pickup holding signal that holds the pickup; A scratch detection circuit that detects scratches, a switching circuit that switches the output signal from a tracking error signal to a pickup holding signal according to the scratch detection signal from the scratch detection circuit, and a tracking servo that receives the output signal from the switching circuit A tracking servo control unit that outputs a control signal, a tracking correction circuit that creates a tracking correction signal based on the scratch detection signal from the scratch detection circuit, a tracking correction signal and a tracking servo control signal when a scratch on the disk is detected. And add An addition circuit for performing calculation and a tracking drive circuit for driving the tracking actuator according to the output from the addition circuit are provided.

According to a second aspect of the present invention, there is provided a pickup for detecting a signal recorded on a disc, a tracking error detection circuit for producing a tracking error signal based on a detection signal from the pickup, and a tracking from the tracking error detection circuit. A pickup holding circuit that inputs an error signal and outputs a pickup holding signal that holds the pickup, a switching circuit that switches and outputs the pickup holding signal and a tracking error signal, and a scratch detection circuit that detects a scratch on the disk. A tracking correction circuit that creates a tracking correction signal that corrects a tracking shift based on a scratch detection signal from the scratch detection circuit, and a tracking error signal for switching from a tracking error signal to a pickup holding signal according to the scratch detection signal from the scratch detection circuit. Switching signal A system controller that outputs an ON signal for turning on the tracking correction circuit and outputs the tracking servo control signal to the switching circuit, and a tracking servo control unit that inputs an output signal from the switching circuit and outputs a tracking servo control signal. And an adder circuit for adding the tracking correction signal and the tracking servo control signal when a scratch on the disk is detected, and a tracking drive circuit for driving the tracking actuator according to the output from the adder circuit. And

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. (Embodiment of the Invention According to Claim 1) FIG. 1 is an overall configuration diagram of a disc player of one embodiment according to the present invention. In the figure, 11 is a compact disc in which music signals are digitally recorded by a pit train, 12 is a spindle motor for rotating the compact disc at a predetermined constant linear velocity, 1
Reference numeral 3 is a pickup for detecting a digital recording signal of the compact disc, 13a is an objective lens for focusing the beam spot on the pit row and tracing the pit row, and 13b is a four-division photodetector for detecting the digital recording signal. Then, four light detection signals A to D are output. 1
Reference numeral 4 is a feed motor for feeding the pickup in the radial direction of the disc, 15 is an RF amplifier for creating an RF signal, a focus error signal FE, and a tracking error signal TE from the signals detected by the pickup, 16 is data demodulation and error detection from the RF signal A digital signal processing circuit that performs processing such as / correction and the like to reproduce subcode data and audio data, 17 is a system controller that controls the entire system, and 18 is an operation / display panel.

A servo processor 19 performs pickup servo control (focus servo control, tracking servo control), pickup feed servo control, spindle servo control and the like. The spindle servo controls the rotation of the disk at n times (for example, 2 times) the normal linear velocity. Reference numeral 19a is a focus servo control unit, 19b is a tracking servo control unit, 19c is a pickup feed servo control unit, and 19d is a spindle servo control unit. Reference numeral 20a denotes a focus driver that drives a focus actuator (not shown) provided on the pickup based on the output of the focus servo control unit, and 20b drives a tracking actuator (not shown) provided on the pickup based on the output of the tracking servo control unit. The tracking driver 20c is a feed motor driver that drives the feed motor 14 based on the output of the pickup feed servo control unit, and 20d is a spindle motor driver that drives the spindle motor 12 based on the output of the spindle servo control unit. Reference numeral 21 is a shock proof memory in which data is written at a double speed and stored data is read at a normal speed in parallel with the writing, 22 is a shock proof memory controller having a microcomputer configuration, and 23 is a D
/ A converter.

Reference numeral 24 denotes a correction signal (correction signal for correcting a tracking error of the pickup by forming a series circuit composed of a resistor (R) and a capacitor (C) and inputting a flaw detection signal DFS from a defect circuit in the RF amplifier 15. 6)), a switching circuit 25 for switching between the tracking error detection circuit of the RF amplifier 15 and the DC hold circuit, and 26 a tracking error circuit at the time when a scratch on the disk is detected. A DC hold circuit that holds the DC level of the error signal (DC hold), and an adder circuit 27 that adds the tracking correction signal from the tracking correction circuit 24 and the tracking servo control signal from the tracking servo control unit 19b.

In the program area of the compact disc 11, control data called a frame synchronization signal or a sub-code is recorded for each frame together with acoustic data. Depending on the Q channel of the serve code,
(1) Song number according to the current position of the pickup, (2) Index (indicates the movement of the song, etc.), (3) Elapsed time from the beginning of the song number (performance time: minutes, seconds, frames) (4) The absolute elapsed time from the initial position of the pickup, etc. is instructed and displayed on the operation / display panel 18 as appropriate.

The system controller 17 is composed of a microcomputer, and displays the music number, the elapsed time for each music, the total elapsed time, etc. on the operation / display panel 18 based on the sub-code Q channel data. Access processing to the desired song number is performed based on the instruction on the display panel, and further, (1) detection of abnormality such as track jump due to shock or scratch, (2) return control of pickup to position immediately before abnormality occurrence , (3) pause control, (4) various servo return control, (5) servo characteristic switching control, (6)
It communicates with the shock proof memory controller 22. The pickup 13 detects a pit string signal (digital recording information) optically recorded on the compact disc 11 by a four-division type photodetector 13b, and A, B,
It outputs four light detection signals of C and D.

The RF amplifier 15 is configured as shown in FIG. 2, and includes a calculator 15a, a waveform equalizer 15b, a waveform shaping circuit 15c, a focus error detection circuit 15d, a tracking error detection circuit 15e, and an RF normality detection circuit 15f.
It has a defect circuit 15g. The arithmetic unit 15a adds all the photodetection signals A to D output from the pickup 13 by the arithmetic unit 15a to create an RF signal. The RF signal is subjected to waveform equalization and waveform shaping by the waveform equalizer 15b and the waveform shaping circuit 15c, and the EFM signal is output to the digital signal processing circuit 16. The focus error detection circuit 15d outputs the focus error signal FE by performing the operation of (A + C)-(B + D), and the tracking error detection circuit 15e performs the operation of (A + B)-(C + D). The signal TE is output.
Here, the tracking error signal TE was obtained by the push-pull method using one beam, but three using three beams.
The tracking error signal TE can be obtained by the beam method or the DPD method which is an improved push-pull method.

The focus error detection circuit 15d and the tracking error detection circuit 15e are supposed to amplify and output the focus error signal FE and the tracking error signal TE, respectively. The RF normality detection circuit 15f outputs an H-level RFOK signal to the servo processor when the average signal level detected by passing the RF signal output from the calculator 15a through the low-pass filter is equal to or higher than a predetermined reference level (see FIG. 3). ). The defect circuit 15g holds the upper envelope of the RF signal output from the calculator 15a with a large time constant, and when the upper envelope is lowered by a certain level or more, the defect detection signal DFS of H level indicating that there is a flaw. Is output (see FIG. 4). The L level of the RFOK signal indicates that the focus servo is out.

Since the compact disc 11 is controlled to rotate at a linear velocity n times (eg, twice) the normal rotational speed, the reproducing system of the pickup 13, the RF amplifier 15, and the digital signal processing circuit 16 is an ordinary CD player. The digital recording information is read at a speed twice as fast as that in (double speed reproduction).

The shock proof memory 21 is composed of a DRAM and has a capacity for recording data of a length of about 2.8 seconds. Under the control of the shock proof memory controller 22, the data is written at a normal double speed and a normal speed. The data can be read at. The shockproof memory controller 22 controls writing / reading of data to / from the shockproof memory 21. For example, (1) the system controller 17 monitors whether or not there is an abnormality occurrence notification, and when an abnormality occurs, writing to the shock proof memory 21 is stopped (reading continues). Also, (2) monitor whether the shock proof memory 21 is full of data (data full),
When the data becomes full, the system controller 17 is notified of the full data and the shockproof memory 21
Stop writing (reading continues). Then, when the reading is continued and a predetermined number of data is read and a vacancy occurs, the system controller 17
And the writing of the data input from the digital signal processing circuit 16 is restarted. Further, (3) at the time of writing data to the shock proof memory 21, writing is performed based on a predetermined clock signal input from the digital signal processing circuit 16, and thereby double speed writing is performed to the shock proof memory 21.

The digital signal processing circuit 16 performs processing such as clock reproduction, synchronization detection, data demodulation, error detection / error correction, etc. on the EFM signal input from the RF amplifier 15 and outputs audio data to the shock proof memory controller 22. Or read the subcode and output it to the system controller 17. A sync signal generator 16a is provided in the digital signal processing circuit to generate a sync signal SYS.

FIG. 5 shows the structure of the tracking servo control section 19b. 19b-1 is a band limiting circuit, 19b-2 is a phase compensation circuit, 19b-3 is a servo switch, 19b-4 is a control section, 19b-
5 is adder, 19b-6 is jump mode switch, 19b-7
Is a jump pulse generator. The band limiting circuit 19b-1 performs a predetermined band limitation on the tracking error signal TE, but the band is widened by opening and closing the switch SW1 (SW1
It is designed to switch between two stages: open) and normal band (when SW1 is closed) (see Fig. 6). That is, SW2 is normally closed, but when vibration is detected (subcode Q
For the absolute time information obtained from the information, and by monitoring the focus servo out-of-focus detection circuit (not shown), switch S
W1 is opened, and the servo gain is switched to a wide band by R6, C4, and R7 so that the servo can follow the frequency component with a high center deviation. However, band switching is not performed when a flaw is detected.

The phase compensating circuit 19b-2 stabilizes the servo by performing phase compensation in the high frequency region on the tracking error signal TE after the band is limited. In conjunction with this, the phase compensation characteristic is switched in two stages by opening / closing the switch SW2 (see FIG. 7). That is, SW2 is normally closed, but when vibration is detected, the switch SW2 is opened and R9
, R10, C5 increase the peak frequency of phase compensation in accordance with the widening of the servo gain. However, phase switching is not performed when a flaw is detected. The switch S
System control 1 for switching control between W1 and SW2
7 done.

The servo switch 19b-3 is controlled to be opened / closed by the control unit 19b-4. When the tracking servo OFF command is given from the system controller 17, the control unit 19b-4 opens the servo switch 19b-3. Further, when a servo-on command is given from the system controller 17, the servo switch is turned on at a predetermined timing optimal for turning on the tracking servo (for example, the center run-out speed of the disk is near zero and the servo is a negative feedback). 19b-3
Close. After the servo switch 19b-4 is closed, the tracking error signal TE changes in proportion to the deviation of the beam spot from the track center, and the tracking error signal TE changes from the tracking error signal TE to the band limiting circuit 19b-1 and the phase compensation circuit 19b-2. After band limitation and phase compensation have been performed by the servo switch 19
tracking driver 20 via b-3 and adder 19b-5
Then, the tracking driver 20b drives the tracking actuator 20b after amplification, and moves the objective lens 13a to track the track in the disk radial direction.

The adder 19b-5 is used by the system controller 1 when performing a medium-range search (for example, in units of several hundred tracks).
The step jump signal input from 7 is output to the tracking driver 20b, and the beam spot can be moved to a desired position by jumping over a plurality of tracks in the disk radial direction. When performing a short distance search, the jump mode switch 19b-6 is closed for a short time under the control of the system controller 17, and the jump pulse signal generated by the jump pulse generator 19b-6 under the control of the system controller 17 (forward jump). Pulse or reverse jump pulse) servo switch 19b-
It is applied to the output side of 3 so that the beam spot can be moved to a desired position in the radial direction of the disk in units of one track.

The operation of the disc player of the present invention will be described. Referring to FIG. 1, when a performance is instructed on the operation display panel 18, the system controller 17 issues a command to the servo processor 19 so that the focus servo is turned on, the spindle motor 12 is started, the tracking servo is turned on, and the spindle servo is turned on. Turn on various servos. At this time, the switch (not shown) of the band limiting circuit of the focus servo control unit 19a and the switch SW1 of the band limiting path 19b-1 of the tracking servo control unit 19b are closed to make the servo gain characteristic of the normal band, and the focus servo A switch (not shown) of the phase compensation circuit of the control unit 19a and the tracking servo control unit 19b.
The switch SW2 of the phase compensating circuit 19b-2 is closed to obtain the normal phase compensation characteristic, and the servo characteristic is set to the normal state. As a result, the spindle motor 12 rotates the compact disc 11 at a double linear velocity, and the pickup 13 and the RF amplifier 15 read digital recording information from the compact disc at double velocity. The digital signal processing circuit 16 performs processing such as data demodulation and error detection / correction on the EFM signal input from the RF amplifier 15, outputs audio data together with a clock, and extracts a subcode and outputs it to the system controller 17. .

In parallel with the above operation, the system controller 17 uses the subcode Q channel data to check whether a performance abnormality due to a scratch has occurred. Specifically, first, the absolute time information (total elapsed time) obtained from the subcode Q channel data is monitored, and when the elapsed time is interrupted or discontinuous, it is determined that there is an abnormality. If there is no abnormality, it is checked whether the shock proof memory controller 22 has received a notification (data full signal) that the shock proof memory 21 is full of data.

If the data full signal is not received, in other words, if the shock proof memory 21 is not data full, the predetermined process is continued. Double-speed scanning of is temporarily stopped (pause state). In the paused state, the rotation of the spindle motor 12 is not stopped, absolute time information at the pause start position is stored, and the pickup 13 is stored in advance every time the pickup 13 moves for a predetermined time. By repeating the operation of returning to the position indicated by the absolute time information, the pickup 13
Maintain at the pose start position.

After that, it is monitored whether or not a data empty signal is received from the shock proof memory controller 22, and if it is not received, the pause state is continued, and if it is received, the pause state is canceled and a predetermined process is repeated. After the data is full, a predetermined number of data is read from the shock proof memory 21, and when an appropriate amount of free space is created in the memory, the shock proof memory controller 22 sends a data free signal to the system controller 17.

The above is the case where no abnormality occurs in the performance, but when an abnormality such as a scratch on the disk occurs, the switching circuit 25 is a switching element such as an analog switch, and the defect circuit of the RF amplifier 15 is used. The scratch detection signal DFS from 15g is received and switching control is performed from the tracking error detection circuit 15e side to the DC hold circuit 26 side, and at the same time as this switching operation, the tracking correction circuit 24 inputs the scratch detection signal DFS and outputs a correction signal. It is created and input to the adder 27. The adder 27 inputs a signal corresponding to the flaw detection signal DFS as shown in FIG. 9 to the tracking driver 20b and inputs the objective lens 13a of the pickup 13 to the tracking driver 20b.
To move to the outside. Thereby, the tracking error of the pickup 13 can be corrected.

(Embodiment of the Invention According to Claim 2) FIG.
Reference numeral 0 is an overall configuration diagram of a disc player according to an embodiment of the present invention. In the figure, 11 is a compact disc in which a music signal is digitally recorded by a pit train, 12 is a spindle motor for rotating the compact disc at a predetermined constant linear velocity, and 13 is a pickup for detecting a digital recording signal of the compact disc, Reference numeral 13a is an objective lens for focusing the beam spot on the pit row and tracing the pit row, and 13b is a four-division photodetector for detecting a digital recording signal, which outputs four light detection signals A to D. 14 is a feed motor that feeds the pickup in the radial direction of the disc, 15 is an RF amplifier that creates an RF signal, a focus error signal FE, and a tracking error signal TE from the signals detected by the pickup, 16 is data demodulation and error detection from the RF signal / Perform processing such as correction,
A digital signal processing circuit that reproduces subcode data and audio data, a system controller 17 that controls the entire system, and a control / display panel 18.

A servo processor 19 performs pickup servo control (focus servo control, tracking servo control), pickup feed servo control, spindle servo control, and the like. The spindle servo controls the rotation of the disk at n times (for example, 2 times) the normal linear velocity. Reference numeral 19a is a focus servo control unit, 19b is a tracking servo control unit, 19c is a pickup feed servo control unit, and 19d is a spindle servo control unit. Reference numeral 20a denotes a focus driver that drives a focus actuator (not shown) provided on the pickup based on the output of the focus servo control unit, and 20b drives a tracking actuator (not shown) provided on the pickup based on the output of the tracking servo control unit. The tracking driver 20c is a feed motor driver that drives the feed motor 14 based on the output of the pickup feed servo control unit, and 20d is a spindle motor driver that drives the spindle motor 12 based on the output of the spindle servo control unit. Reference numeral 21 is a shock proof memory in which data is written at a double speed and stored data is read at a normal speed in parallel with the writing, 22 is a shock proof memory controller having a microcomputer configuration, and 23 is a D
/ A converter.

Reference numeral 24 is a tracking correction circuit having an IC structure, for example, which inputs a flaw detection signal DFS from the defect circuit 15g of the RF amplifier 15 and creates a correction signal for correcting a tracking error of the pickup.
Tracking error detection circuit 15e of amplifier 15 and DC
A switching circuit for switching to the hold circuit 26, a DC hold circuit 26 for holding the DC level in the tracking error circuit at the time when a scratch on the disk is detected (DC hold), and 27 a servo control signal for the tracking correction circuit 24. Is an addition circuit for adding the tracking correction signal from the tracking servo control signal from the tracking servo circuit 19b.

Since the compact disc 11 is controlled to rotate at a linear velocity n times (for example, twice) the normal rotational speed, the reproducing system of the pickup 13, the RF amplifier 15, and the digital signal processing circuit 16 is an ordinary CD player. The digital recording information is read at a speed twice as fast as that in (double speed reproduction). The pickup 13 detects a pit string signal (digital recording information) optically recorded on the compact disc 11 by a four-division type photodetector 13a,
It outputs four light detection signals of B, C, and D. The digital signal processing circuit 16 uses the EFM input from the RF amplifier 15.
Clock reproduction, synchronization detection, data demodulation, error detection / error correction, etc. are performed on the signal to output audio data to the shock proof memory controller 22, or a subcode is read to read the system controller 17
Output to A sync signal generator 16a is provided in the digital signal processing circuit to generate a sync signal SYS.

The shock proof memory 21 is composed of a DRAM and has a capacity capable of recording data having a length of about 2.8 seconds. Under the control of the shock proof memory controller 22, the data is written at the normal double speed, and the normal speed is set. The data can be read at. The shockproof memory controller 22 controls writing / reading of data to / from the shockproof memory 21. A detailed description of the compact disc 11, the RF amplifier 15, the tracking servo control unit 19b, and the shock proof memory controller 22 has been described in the embodiment according to claim 1, and will not be repeated here.

The system controller 17 is composed of a microcomputer, and displays the music number, the elapsed time for each music, the total elapsed time, etc. on the operation / display panel 18 based on the sub-code Q channel data. Access processing to the desired song number is performed based on the instruction on the display panel, and further, (1) detection of abnormality such as track jump due to shock or scratch, (2) return control of pickup to position immediately before abnormality occurrence , (3) pause control, (4) various servo return control, (5) servo characteristic switching control, (6)
It communicates with the shock proof memory controller 22. The pickup 13 detects a pit string signal (digital recording information) optically recorded on the compact disc 11 by a four-division type photodetector 13b, and A, B,
It outputs four light detection signals of C and D. Then, the flaw detection signal DFS from the defect circuit 15g is input, a switching signal for switching from the tracking error detection circuit 15e side to the DC hold circuit 26 side is output to the switching circuit 25, and the tracking correction circuit 24 is turned on. Output an ON signal for.

The operation of the disc player of the present invention will be described below. FIG. 13 is a flow chart showing the processing of the system controller 17 in the present invention. First, when performance is instructed on the operation display panel 18, the system controller 17 issues a command to the servo processor 19 to turn on various servos in the order of focus servo on, spindle motor 12 startup, tracking servo on, and spindle servo on. (Step 101). At this time, a switch (not shown) of the band limiting circuit of the focus servo controller 19a and the tracking servo controller 19b.
The switch SW1 of the band limiting path 19b-1 is closed to obtain the servo gain characteristic of the normal band, the switch (not shown) of the phase compensation circuit of the focus servo control unit 19a and the phase compensation circuit 19b of the tracking servo control unit 19b. Set the -2 switch SW2 to the normal phase compensation characteristic to set the servo characteristic to the normal state. As a result, the spindle motor 12 rotates the compact disc 11 at a double linear velocity, and the pickup 13 and the RF amplifier 15 read digital recording information from the compact disc at a double velocity. The digital signal processing circuit 16 is the RF amplifier 1
Data demodulation and error detection from the EFM signal input from 5
Processing such as correction is performed, audio data is output together with the clock, and subcodes are extracted and output to the system controller 17 (step 102).

In parallel with the above operation, the system controller 17 uses the subcode Q channel data to check whether a performance abnormality due to a scratch has occurred. Specifically, first, the absolute time information (total elapsed time) obtained from the subcode Q channel data is monitored, and when the elapsed time is interrupted or discontinuous, it is determined that there is an abnormality. If there is no abnormality, it is checked whether the shock proof memory controller 22 has received a notification (data full signal) that the shock proof memory 21 is full of data (step 104).

If the data full signal has not been received, in other words, if the shock proof memory 21 is not data full, the processing from step 102 onward is continued. Double-speed reading of the data of is temporarily stopped (pause state). In the paused state, the spindle motor 1
2 rotation is not stopped, absolute time information at the pause start position is stored, and each time the pickup 13 moves for a predetermined time, the position indicated by the previously stored absolute time information is shown. The pickup 13 is maintained at the pause start position by repeating the operation of returning to step (step 1
05).

Thereafter, it is monitored whether or not a data empty signal is received from the shock proof memory controller 22 (step 106). If it is not received, the pause state is continued, and if it is received, the pause state is released and the process returns to step 102. The process of is repeated. After the data is full, a predetermined number of data is read from the shock proof memory 21, and when an appropriate amount of free space is created in the memory, the shock proof memory controller 22 sends a data free signal to the system controller 17.

The above is the case where no abnormality has occurred in the performance, but if an abnormality occurs, YES in step 103.
Becomes Here, the system controller 17 uses the flaw detection signal DF from the defect circuit 15g of the RF amplifier 15.
When S is received, a switching signal CS is output to the switching circuit 25, and switching control is performed from the tracking error detection circuit 15e side to the DC hold circuit 26 side (step 107). At the same time as this switching operation, the system controller 17
Turns on the tracking correction circuit 24 and inputs the flaw detection signal DFS. The tracking correction circuit 24 creates a tracking correction signal from the flaw detection signal DFS and inputs this signal to the adder 27. The tracking error of the pickup 13 can be corrected by the addition signal of the tracking correction signal and the tracking servo control signal.

[0036]

According to the present invention, since the tracking error is corrected by the tracking correction signal,
It is possible to prevent sound skipping due to the tracking servo being disengaged with respect to a scratch.

[Brief description of the drawings]

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

FIG. 2 is a configuration diagram of an RF amplifier.

FIG. 3 is an operation waveform diagram of an RF normality detection circuit.

FIG. 4 is an operation waveform diagram of the defect circuit.

FIG. 5 is a configuration diagram of a tracking servo control unit.

FIG. 6 is a diagram showing the operation of the band limiting circuit.

FIG. 7 is a diagram showing the operation of the phase compensation circuit.

FIG. 8 is an explanatory diagram showing a track deviation of a pickup.

FIG. 9 is an output waveform diagram from the tracking correction circuit.

FIG. 10 is a configuration diagram according to an embodiment of the present invention.

FIG. 11 is a flowchart showing the processing of the system controller.

[Explanation of symbols]

 11 Compact Disc 13 Pickup 15 RF Amplifier 16 Digital Signal Processing Circuit 17 System Controller 19 Servo Processor 20b Tracking Driver 24 Tracking Correction Circuit 25 Switching Circuit 26 DC Hold Circuit 27 Adder

Claims (2)

[Claims] 1. A pickup for detecting a signal recorded on a disc, a tracking error detection circuit for generating a tracking error signal by a detection signal from the pickup, and a tracking error signal from the tracking error detection circuit are inputted. A pickup holding circuit that outputs a pickup holding signal that holds the pickup, a scratch detection circuit that detects scratches on the disc, and an output signal is switched from a tracking error signal to a pickup holding signal in accordance with the scratch detection signal from the scratch detection circuit. A switching circuit, a tracking servo control unit that inputs an output signal from the switching circuit and outputs a tracking servo control signal, and a tracking correction circuit that creates a tracking correction signal based on the scratch detection signal from the scratch detection circuit, Disc scratch detected A disc player, comprising: an addition circuit that adds a tracking correction signal and a tracking servo control signal when a recording operation is performed; and a tracking drive circuit that drives a tracking actuator according to an output from the addition circuit. 2. A pickup for detecting a signal recorded on a disc, a tracking error detection circuit for producing a tracking error signal by the detection signal from the pickup, and a tracking error signal from the tracking error detection circuit are inputted. A pickup holding circuit that outputs a pickup holding signal that holds the pickup, a switching circuit that switches and outputs the pickup holding signal and the tracking error signal, a scratch detection circuit that detects a scratch on the disk, and a scratch detection circuit from the scratch detection circuit. A tracking correction circuit that creates a tracking correction signal that corrects the tracking shift based on the scratch detection signal, and a switching signal that switches the tracking error signal to the pickup holding signal according to the scratch detection signal from the scratch detection circuit. Go out In addition, a system controller that outputs an ON signal for turning on the tracking correction circuit, a tracking servo control unit that inputs an output signal from the switching circuit and outputs a tracking servo control signal, and a scratch on the disk A disc player provided with an adder circuit for adding a tracking correction signal and a tracking servo control signal when detected, and a tracking drive circuit for driving a tracking actuator according to an output from the adder circuit. .