JPH09171623A - Optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a reproduced signal on a track by making luminous flux follow up the track on an optical disk and accurately detect attached information on an address of a track-wobble recorded optical disk. SOLUTION: This device is provided with a wobble signal control means 12 which attenuates and adds or subtracts the reproduced signal to or from a track error signal when detecting the attached information of the track-wobble recorded optical disk. If the attached information of the optical disk can not be detected, the reproduced signal is attenuated and added to or subtracted from the track error signal to detect a wobble signal from the output of a track error signal arithmetic circuit 5a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device for detecting a reproduction signal on a track by causing a light beam to follow a track on the optical disk and detecting incidental information such as an address of the track wobble recorded optical disk. In particular, the present invention relates to an optical disc device that enables accurate detection of incidental information.

[0002]

2. Description of the Related Art Generally, when detecting incidental information from an optical disk having a structure for recording incidental information in which a groove for tracking is wobbled, it is detected from a difference in light receiving element output for detecting a track signal. However, if there is an imbalance in the amount of light incident on the light receiving element for track signal detection, common mode noise cannot be sufficiently removed when the difference is taken,
There is a problem that the incidental information cannot be detected accurately.

That is, if there is no imbalance, the common-mode noise removal ratio becomes sufficiently large to allow accurate detection, but if imbalance occurs, it becomes difficult to perform accurate detection. Such a problem is particularly pronounced when the incidental information is detected in a recorded area of an optical disc for recording or reproducing data due to the intensity of reflected light such as CD-R, and the incidental information cannot be detected. In some cases, it cannot be done.

Needless to say, it is desirable to adjust the optical system so that an imbalance in light quantity does not occur, but there is a limit to mechanical adjustment, and it may be delayed due to changes over time or warpage of the medium. The imbalance that occurs in the inevitable. As one method for solving such an inconvenience, a reproduction signal is generated from a sum signal of two light receiving elements divided in the track tangential direction, and the two light receiving element outputs are normalized by the reproduction signal and normalized. A method of detecting incidental information from the difference between the signals has been proposed (Japanese Patent Laid-Open No. 6-290462).

In this case, the reproduced signal has a signal band of several 100 KHz or more, and two normalizing circuits are required in this signal band, resulting in an increase in cost. That is, the normalization circuit in the signal band of such a reproduction signal has 2
Since the number of circuits is increased, the circuit scale is increased and three detection circuits are also required, which results in an increase in cost. The inventor of the present application has previously described an optical disc device capable of detecting incidental information of a disc by applying an offset voltage to a position sensor arithmetic circuit and moving an objective lens to remove track asymmetry. Proposed (Japanese Patent Application No. 7-2333)
No. 26, joint invention of "optical disk device").

[0006]

As described in the prior art, when wobbling a tracking groove to detect incidental information such as an address recorded on a disk, for example, a pair of tracks for detecting a track signal is generally used. It is detected from the difference in the output of the light receiving element. In this case, if there is an imbalance in the amount of light incident on the light receiving element for track signal detection, common mode noise cannot be sufficiently removed when the difference between the light receiving element outputs is taken, and incidental information cannot be accurately detected. , There is a problem.

Conversely, if there is no such imbalance, the common-mode noise removal ratio can be made sufficiently large, and the incidental information can be accurately detected. According to the present invention, when the reproduction signal mixes with the track error signal and the incidental information of the optical disc cannot be detected, the reproduction signal is attenuated and addition and subtraction are performed with the track error signal to determine the mixing amount of the reproduction signal into the track error signal. Smaller,
The wobble signal (incidental information) can be detected from the track error signal output from the track error signal arithmetic circuit (the invention of claims 1 to 10).

[0008]

According to another aspect of the present invention, there is provided an optical disk apparatus, wherein a focus control means for focusing a light beam from a semiconductor laser on the optical disk by an objective lens, a track control means, and an objective lens in a radial direction of the optical disk. An optical disk device comprising a carriage servo means for moving, which detects a reproduction signal on a track by causing a light beam to follow a track on the optical disk and detects incidental information of the track-wobble-recorded optical disk. Depending on the difference between the plurality of track light receiving elements that detect the deviation of the emitted light flux from the track center, the I / V conversion circuit that converts the output from the track light receiving element into a current / voltage, and the output from the I / V conversion circuit. A track error signal calculation circuit for generating a track error signal;
In an optical disc device having a reproduction signal calculation circuit for generating a reproduction signal by summing outputs from a V / V conversion circuit, wobble signal control means for attenuating the reproduction signal and adding / subtracting to / from a track error signal, and controlling the wobble signal control means When the incidental information of the optical disc cannot be detected, the CPU attenuates the reproduction signal to add / subtract the track error signal, and detects the wobble signal from the output of the track error signal calculation circuit.

According to the optical disk device of claim 2, claim 1
In the optical disc device, the wobble signal control means is
A first and a second analog switch connected to the reproduction signal, an inverter for switching the first and the second analog switch on / off by a signal from the CPU, and a reproduction signal connected to the first analog switch And a second electronic volume that is connected to the second analog switch and that attenuates the reproduced signal and subtracts it from the track error signal. .

According to the optical disk device of claim 3, claim 1
In the optical disc device, the reproduction signal mixing amount detecting means for detecting the mixing amount of the reproduction signal in the track error signal is provided, and the attenuation amount of the reproduction signal amplitude for adding / subtracting to / from the track error signal is set to the track of the reproduction signal in the track-on state. It is determined so that the mixing into the error signal is minimized.

According to the optical disk device of claim 4,
Therefore, in the optical disk device according to the third aspect, the attenuation amount of the reproduction signal amplitude which is added to or subtracted from the track error signal is changed according to the radial position of the optical disk.

According to the optical disk device of claim 5,
Therefore, in the optical disk device according to the fourth aspect, the amount of attenuation of the reproduction signal amplitude that is added to or subtracted from the track error signal is limited.

According to the optical disk device of claim 6,
Therefore, in the optical disk device according to the fifth aspect, when the power is turned on or when the optical disk is inserted, the reproduction signal is attenuated and added to or subtracted from the track error signal.

According to the optical disk device of claim 7,
Therefore, in the optical disk device according to the sixth aspect, the temperature detecting means is provided, and the reproduction signal is attenuated again by the temperature change, and the track error signal is added or subtracted.

According to the optical disk device of claim 8,
Therefore, in the optical disc device according to the seventh aspect, the attenuation amount of the reproduction signal amplitude which is added to or subtracted from the track error signal is readjusted at predetermined time intervals.

According to the optical disk device of claim 9, claim 1
Therefore, in the optical disk device according to the eighth aspect, the attenuation amount of the RF signal amplitude to be added to or subtracted from the track error signal is readjusted immediately before the data recording or reproducing operation.

According to a tenth aspect of the present invention, in the optical disc apparatus according to the third aspect, there is provided a storage means for storing a parameter relating to a reproduction signal mixing amount and a reproduction signal amplitude attenuation rate when the reproduction signal is added or subtracted. The CPU, when detecting the mixed amount of the reproduced signal, attenuates the reproduced signal in accordance with the parameter stored in the storage means and adds or subtracts the track error signal.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to an optical disc device for detecting incidental information such as an address of an optical disc on which track wobble recording is performed, and more specifically, it realizes an optical disc device which enables accurate detection of incidental information. The invention of claim 1 is the basic invention, and all the inventions of claims 2 to 10 are based on the invention of claim 1. First, an example of an embodiment of the overall configuration of an optical disc device of the present invention will be described with reference to the drawings.

FIG. 1 is a functional block diagram showing an example of an embodiment of the main configuration of the optical disk device of the present invention. In the figure, 1 is an optical disk, 2 is a spindle motor, 3 is an optical pickup, 4 is a focus control means, 4a is a focus error signal operation circuit, 5 is a track control means, 5a is a track error signal operation circuit, and 6
Is a carriage servo means, 7 is a preamplifier, 8 is RF
Signal arithmetic circuit, 9 servo controller, 10 CPU
FE indicates a focus error signal, TE indicates a track error signal, and RF indicates a reproduction signal.

The structure and operation of the optical disk device shown in FIG. 1 are as follows. The optical disc 1 is rotationally driven by a spindle motor 2. Optical pickup 3
Includes a semiconductor laser, an optical system, a focus actuator, a track actuator, a four-division light receiving element, and a position sensor (not shown), and irradiates the optical disc 1 with laser light. This optical pickup 3
Receives the reflected light from the optical disc 1 and gives its output to the focus control means 4 and the track control means 5 via the preamplifier section 7 in the next stage.

The focus control means 4 produces a focus error signal FE from the received light receiving signal, and the track control means 5 similarly produces a track error signal TE from the light receiving signal. In addition, by giving the output of the preamplifier section 7 to the RF signal arithmetic circuit 8 and adding it,
Reproduction signal RF of optical disc 1 (hereinafter referred to as RF signal)
Is generated. Here, the generation of the RF signal will be described. The RF signal is generated by the preamplifier section 7, the focus control means 4, the track control means 5, and the RF signal calculation circuit 8 shown in FIG. A circuit for generating this RF signal will be described with reference to FIGS. 2 and 3 below.

FIG. 2 is a circuit diagram showing an example of a detailed configuration of an RF signal generation circuit around the RF signal arithmetic circuit 8 of FIG. Reference numerals in the figure are the same as those in FIG. 1, 7A to 7D are respective I / V conversion circuits of the preamplifier section 11, 11 is a four-division light receiving element, 11A to 11D are their respective light receiving elements, and 12 is a wobble signal control means. Show, V
ref indicates the reference voltage.

FIG. 3 shows the wobble signal control means 12 of FIG.
FIG. 3 is a diagram showing an example of an embodiment of a detailed configuration of the above. Reference numerals in the figure are the same as those in FIG. 2, 12A is a first analog switch, 12B is a second analog switch, 12C is a first electronic volume, 12D is a second electronic volume, and 12E is an inverter.

The preamplifier section 7 includes I / V conversion circuits 7A to 7A.
It is composed of four 7D I / V conversion circuits. As shown in FIG. 2, the preamplifier unit 7 of FIG. 1 corresponds to each of the light receiving elements 11A to 11D of the four-division light receiving element 11,
It is composed of a total of four I / V conversion circuits of V conversion circuits 7A to 7D. These light receiving elements 11A to 11D are four-division light receiving elements built in the optical pickup 3 of FIG.

Then, each light receiving element 11 of the four-division light receiving element
The outputs of A to 11D are current-voltage converted by the corresponding I / V conversion circuits 7A to 7D, and given to the track error signal operation circuit 5a, the focus error signal operation circuit 4a, and the RF signal operation circuit 8 in the next stage. . The track error signal calculation circuit 5a and the focus error signal calculation circuit 4a perform calculations on the outputs of the I / V conversion circuits 7A to 7D. As shown in FIG. 1, the track error signal calculation circuit 5a is built in the track control means 5, and the focus error signal calculation circuit 4a is built in the focus control means 4.

Further, the focus error signal arithmetic circuit 4a
In the RF signal operation circuit 8 to which the same output signal as
The outputs of the respective I / V conversion circuits 7A to 7D are added to generate an output centered on the reference voltage Vref and output to the wobble signal control means 12. The wobble signal control means 12
As shown in detail in FIG. 3, the first for adjusting the attenuation rate when the RF signal is added to the track error signal TE.
Electronic volume 12C, a second electronic volume 12D for adjusting the attenuation rate when the RF signal is subtracted from the track error signal TE, and the track error signal TE.
To the first analog switch 12A which is turned on when the RF signal is added to the track error signal TE
It is composed of a second analog switch 12B which is turned on when the F signal is subtracted, and an inverter 12E for switching between the first and second two analog switches 12A and 12B by a signal from the CPU 10.

The track error signal operation circuit 5a is composed of an operational amplifier, and the inverting input terminal of the operational amplifier is connected to the second electronic volume 12D in the wobble signal control means 12. The non-inverting input terminal of the operational amplifier is connected to the first electronic volume 12C in the wobble signal control means 12. When adding the RF signal to the track error signal TE, the CPU 1
0 to Inverter 12E in wobble signal control means 12
To the second analog switch 12 by turning on the first analog switch 12A by sending a control signal to the second analog switch 12A.
Set B to the off state.

In this case, the CPU 10 can attenuate and add the RF signal by changing the resistance value of the first electronic volume 12C. For example, if the resistance value of the first electronic volume 12C is made larger than the value of the feedback resistance of the operational amplifier in the track error signal calculation circuit 5a, the RF signal can be attenuated and added.
Since the RF signals are not amplified and added,
It is not necessary to select the resistance value of the first electronic volume 12C smaller than the value of the feedback resistance of the operational amplifier in the track error signal calculation circuit 5a.

When the RF signal is subtracted from the track error signal TE, the control signal is sent from the CPU 10 to the inverter 12E in the wobble signal control means 12 to turn off the first analog switch 12A and the second analog switch 12A. The analog switch 12B is set to the ON state. The CPU 10 can attenuate and subtract the RF signal by changing the resistance value of the second electronic volume 12D. That is, when the resistance value of the second electronic volume 12D is made larger than the value of the feedback resistance of the operational amplifier in the track error signal calculation circuit 5a, the RF signal can be attenuated and subtracted. The circuits related to the generation of the RF signal shown in FIGS. 2 and 3, that is, the preamplifier section 7, the focus control means 4, the track control means 5, and the RF signal calculation circuit 8 shown in FIG. It has a function to generate.

Now, returning to FIG. 1, the focus error signal FE generated by the focus error signal operation circuit 4a in the focus control means 4 is a phase correction circuit (not shown) and a drive for stabilizing the servo system. It is output as a control signal to the focus actuator of the optical pickup 3 via an amplifier (not shown). The focus servo system has such a configuration. The same applies to the track servo system, in which the track error signal TE generated by the track error signal calculation circuit 5a in the track control means 5 stabilizes the servo system by a phase correction circuit (not shown) and a drive amplifier (not shown). Is output as a control signal to the track actuator of the optical pickup 3 via.

The focus control means 4 and the track control means 5 are controlled by the servo controller 9. The track error signal TE is also supplied to the carriage servo means 6 via a phase correction circuit (not shown) and a drive amplifier (not shown), which move the optical pickup 3 in the radial direction of the optical disc 1. A carriage servo system for performing the operation is configured. The optical pickup 3 will be described below with reference to FIGS. 4 and 5.

FIG. 4 is an exploded perspective view showing the main structure of the optical system provided inside the optical pickup 3. In the figure, the four-division light receiving element 11 is the same as that in FIG. 2, 21 is an aspherical objective lens, 22 is a quarter wavelength plate, 23 is a deflecting prism, 24 is a collimating lens, 2
5 is a polarization beam splitter, 26 is a cylindrical lens, 27 is a semiconductor laser, and 28 is a high frequency superposition module.

FIGS. 5A and 5B are views showing the main structure of the optical system of the optical pickup 3 shown in FIG. 4, in which FIG. 5A is a side view and FIG. . Reference numerals in the drawings are the same as those in FIGS. 2 and 4.

The light emitted from the semiconductor laser 27 is incident on the polarization beam splitter 25. At this time, since the laser light is deflected in the vertical direction, 100% of the laser light that has entered the polarization beam splitter 25 enters the collimator lens 24. Since the collimator lens 24 converts the diffused light into parallel light, the deflection prism 23 has
The vertically polarized parallel light is incident.

The laser light reflected by the deflection prism 23 passes through the quarter-wave plate 22 and passes through the aspherical objective lens 21 to enter the optical disc 1. The polarization direction of the laser light becomes circularly polarized light after passing through the 1/4 wavelength plate 22, and the reflected light from the optical disk 1 becomes circularly polarized light in the opposite direction and is incident on the 1/4 wavelength plate 22 again. This quarter wave plate 2
After passing through 2, the light has a horizontal polarization direction and is incident on the polarization beam splitter 25 via the collimator lens 24.

In this state, since the polarization direction is horizontal, 100% of the incident light is the cylindrical lens 26.
To the four-division light receiving element 11. Each light receiving element of the four-divided light receiving element 11 is composed of four light receiving elements 11A to 11D as shown in the front view (light receiving surface) in FIG.

Here, when the outputs (based on the amount of incident light) of the light receiving elements 11A to 11D are shown by A to D, the generated focus error signal FE, track error signal TE, and reproduction signal RF are as follows. It can be represented by an expression such as. Signal FE = (A + C)-(B + D) Signal TE = (A + B)-(C + D) Signal RF =-(A + B + C + D) The above is all the inventions (the inventions of claims 1 to 10) of the optical disk device of the invention. 2) is a configuration and an operation common to the embodiment of FIG. The embodiments of the invention described below are based on the optical disk device described above.

First Embodiment The first embodiment is mainly claim 1 and claim 2.
Although it corresponds to the invention of claim 1, it is also related to the inventions of claims 3 to 10, and the invention of claim 1 is the basic invention. In the optical disk device of the present invention, the reason why the incidental information of the optical disk cannot be accurately detected is that the reproduction signal is mixed with the track error signal. If the reproduction signal is attenuated and addition and subtraction are performed with the track error signal, the reproduction signal Focusing on the fact that it is possible to reduce the amount of mixing in the track error signal, when the incidental information of the optical disc cannot be detected, the reproduction signal is attenuated and the track error signal is added or subtracted to reduce the track error. The wobble signal (incidental information) can be reliably detected from the track error signal output from the signal calculation circuit. The first embodiment is characterized in that a wobble signal control means for attenuating the reproduction signal and adding or subtracting the track error signal is added (the invention of claim 1). Also,
Another feature is that the wobble signal control means is composed of a simple circuit (the invention of claim 2).

As described above, by reducing the mixing amount of the reproduced signal into the track error signal, it is possible to accurately detect the wobble signal (supplementary information such as an address). Therefore, in the optical disk device for detecting the incidental information of the optical disk on which track wobble recording is shown in FIG. 1, a plurality of track light receiving elements (four-division light receiving in FIG. 2) for detecting the deviation of the condensed light flux from the track center are detected. Element 11
Each of the light receiving elements 11A to 11D), an I / V conversion circuit (I / V conversion circuits 7A to 7D in FIG. 2) for converting the output from these track light receiving elements into a current / voltage, and these I / V conversion circuits.
A track error signal operation circuit (5a) that generates a track error signal based on the difference in output from the V conversion circuit, and a reproduction signal operation circuit (8) that also generates a reproduction signal based on the sum of outputs from the I / V conversion circuit. Wobble signal control means (12 in FIG. 2) for attenuating the reproduction signal and adding / subtracting to / from the track error signal in the optical disc device having
And a CPU (10) for controlling the wobble signal control means, and when additional information of the optical disc cannot be detected,
The CPU attenuates the reproduced signal, adds to and subtracts from the track error signal, and detects the wobble signal from the output of the track error signal calculation circuit (the invention of claim 1).

The overall structure is as shown in FIG. 1, and the preamplifier section 7 and the focus control means 4,
The detailed configurations of the track control means 5 and the RF signal calculation circuit 8 are shown in FIGS. 2 and 3. Optical pickup 3
Is shown in FIGS. 4 and 5. In the optical disk device of FIG. 1, the CPU 10 rotationally drives the spindle motor 2 by a spindle motor drive (not shown). After that, the semiconductor laser 27 is turned on by a driver (not shown) of the semiconductor laser 27 and the servo controller 9 is instructed to perform the focus servo by the focus control means 4. Further, the track control means 5 applies track servo to read the incidental information (wobble signal) of the optical disc 1 (the incidental information of the optical disc is called a wobble signal,
In the following, the supplementary information and the wobble signal have the same meaning).

In this case, when the supplementary information cannot be detected, the CPU 10 detects the supplementary information again by the following operation. Specifically, in order to set the optimum value of the attenuation amount of the RF signal amplitude to be added to the track error signal and the attenuation amount of the RF signal amplitude to be subtracted (a value that minimizes the mixing amount of the RF signal), the wobble signal The control means 12 attenuates the reproduced signal to add / subtract with the track error signal.

FIG. 6 is a flow chart showing the main processing flow at the time of re-detection of the incidental information of the optical disk in the first embodiment of the present invention. In the figure,
# 1 to # 3 indicate steps.

This control is performed by the CPU 10. In step # 1, the CPU 10 sends a signal to the inverter 12E of FIG. 3 to set the state in which the RF signal is added to the track error signal, turns on the first analog switch 12A, and turns on the second analog switch. 12B
To the off state. In this state, the auxiliary information (wobble signal) of the optical disc 1 is read while changing the resistance value of the first electronic volume 12C.

At step # 2, it is determined whether the incidental information on the optical disc 1 has been read. When the supplementary information has been read, the flow of FIG. 6 ends. If not, go to step # 3. CP in step # 3
On the contrary, the U10, in order to set the state where the RF signal is subtracted from the track error signal, the inverter 12E of FIG.
To switch the first analog switch 12A to the off state and the second analog switch 12B to the on state.

Then, while changing the resistance value of the second electronic volume 12D, the supplementary information of the optical disc 1 is read, and the flow of FIG. 6 is terminated. By the above processing, the mixing amount of the reproduction signal RF into the track error signal TE is reduced, so that the wobble signal can be detected from the output of the track error signal calculation circuit. Therefore, even if the reproduction signal RF is mixed in the track error signal TE, it is possible to reduce the mixing of the reproduction signal RF in the track error signal TE without adding a special circuit, and to accurately attach the optical disc 1 to the optical disc 1. It becomes possible by detecting information (wobble signal) (the invention of claim 1).

Next, the wobble signal control means 12 shown in FIGS. 2 and 3 will be described in detail (the invention of claim 2). This wobble signal control means 12 includes first and second analog switches (12A, 12A) to which reproduction signals are connected.
B), an inverter (12E) for switching ON / OFF of the first and second analog switches, and a first electronic connected to the first analog switch for attenuating the reproduction signal and adding it to the track error signal. Volume (12C)
And a second electronic volume (12D) connected to the second analog switch for attenuating the reproduction signal and subtracting it from the track error signal.

The CPU 10 outputs RF to the track error signal.
Inverter 12 is used to set the state of adding signals.
A signal is sent to E to set the first analog switch 12A to the on state and the second analog switch 12B to the off state. In this case, the signal output from the CPU 10 is inverted by the inverter 12E, so that the signal output to the first analog switch 12A and the signal output to the second analog switch 12B have opposite polarities.
Therefore, when the first analog switch 12A is on, the second analog switch 12B is off, and when the first analog switch 12A is off, the second analog switch 12B is on.

By such switching control, the RF signal is connected to the non-inverting input terminal of the operational amplifier in the track error signal operation circuit 5a via the first electronic volume 12C and added to the track error signal. The RF signal amplitude (attenuation rate) to be added is determined by the resistance value of the first electronic volume 12C, and the resistance value of the first electronic volume 12C can be variably controlled by a signal from the CPU 10. . So, first,
If the incidental information is detected while changing the resistance value of the electronic volume 12C, the optimum resistance value can be set.

In this case, if the optimum resistance value is not set even if the RF signal is added to the track error signal (when the additional information cannot be read), the RF signal is subtracted from the track error signal. That is, the CPU 10 sends a signal to the inverter 12E to set the state in which the RF signal is subtracted from the track error signal, sets the first analog switch 12A in the off state, and sets the second analog switch 12B in the on state. To do.

By this switching, the RF signal is connected to the inverting input terminal of the operational amplifier in the track error signal operation circuit 5a via the second electronic volume 12D,
Subtracted from the track error signal. The RF signal amplitude to be subtracted can be controlled by the resistance value of the second electronic volume 12D by the signal from the CPU 10, and the wobble signal is changed while sequentially changing the resistance value of the second electronic volume 12D. An optimum resistance value is set by detecting the wobble signal.

The resistance value can be set at high speed by using a known difference method algorithm. The CPU 10 determines whether or not the wobble signal can be detected by using a wobble signal (44.1 KHz ± 2 KHz during double speed reproduction) from the track error signal in the track-on state.
So that only the signal modulated by C.) is detected, FM demodulation is performed through a bandpass filter, and the demodulated data is C
This can be done by reading by the PU 10. Note that FIG.
The wobble signal control means 12 shown in FIG. 3 and FIG. 3 show a basic configuration and an operating principle. When the auxiliary information of the optical disk can be detected, the wobble signal control means 12 does not operate (first and second electronic devices). It goes without saying that the resistance values of the volumes 12C and 12D are set to 0) and the wobble signal control means 12 is separated so that addition and subtraction with the track error signal are not performed (the output of the wobble signal control means 12 is invalidated). Nor. As described above, the wobble signal control means 12 is
Since it is possible to reduce the amount of the RF signal mixed into the track error signal, it is possible to accurately detect the incidental information, and the cost can be reduced because the circuit is simple.

Second Embodiment This second embodiment corresponds to the invention of claim 3, but is also related to the invention of claim 1. This claim 3
In the invention, the hardware configuration is the same as that of the invention of claim 1 or claim 2, and the optical disk device (preamplifier section 7 and focus control means 4,
It is premised on the track control means 5, the RF signal calculation circuit 8) and the like. In the second embodiment (the invention of claim 3),
2. The optical disk device according to claim 1, further comprising a reproduction signal mixing amount detecting means for detecting a mixing amount of the reproduction signal into the track error signal, and reproducing the attenuation amount of the reproduction signal amplitude for adding / subtracting to / from the track error signal in the track-on state. The feature is that the signal is determined so as to be minimally mixed with the track error signal.

FIG. 7 is a diagram for explaining a waveform in a state where the reproduction signal RF is mixed in the wobble signal. (1) is a normal wobble signal (a state in which the reproduction signal RF is not mixed), and (2)
Represents a wobble signal mixed with the reproduced signal RF, and (3) represents the mixed reproduced signal RF.

The wobble signal is 4 when reproducing at double speed.
4.1 KHz ± 2 KHz (that is, 42.1 KHz to 46.
It is a signal of 1 KHz) and is a signal in which incidental information such as an address is FM-modulated. Wobble signal amplitude is 100 mVp
The amplitude is about p, and the RF signal amplitude is about 1 Vpp or more, while the amplitude is very small. Therefore, R
The F signal has a great influence on the wobble signal. Note that m
Vpp and Vpp indicate voltages between positive and negative peak values.

For example, as shown in FIG. 7 (1), when the reproduction signal RF is mixed with the normal wobble signal, the waveform is distorted as shown in FIG. 7 (2). In this case, the reproduced signal RF mixed is shown in FIG. 7 (3). The frequency of the reproduction signal RF is 785 KHz (corresponding to 11T by EFM modulation: EIGHT TO FOR for EFM modulation) at the time of double speed reproduction.
TEEN MODELATION system) ~ 2.88MHz
The signal frequency is (equivalent to 3T in EFM modulation). next,
A circuit for extracting only the reproduction signal RF from the wobble signal in which the reproduction signal RF is mixed as shown in FIG. 7 (2), that is, an RF signal mixing amount detecting means will be described.

FIG. 8 shows an optical disc apparatus R of the present invention for extracting a reproduction signal RF mixed with a wobble signal.
It is a functional block diagram which shows an example of embodiment of the F signal mixing amount detection circuit. The reference numerals in the figure are the same as those in FIG.
31 is a high pass filter, 32 is a peak hold circuit,
Reference numeral 33 indicates an A / D conversion circuit.

The high-pass filter 31 is a filter that passes only the high frequency component of the track error signal TE output from the track error signal operation circuit 5a shown in FIG. For example, as shown in FIG. 7B, when a waveform in which the reproduction signal RF is mixed is input, only the mixed reproduction signal RF is passed. Since the wobble signal is 46.1 KHz (maximum) during double speed reproduction, if the cutoff frequency is set to about 500 KHz, the frequency component of the wobble signal is blocked and only the frequency component of the reproduction signal RF is passed. be able to.

The reproduced signal RF that has passed through the high-pass filter 31, that is, the reproduced signal RF component mixed in the wobble signal is processed by the peak hold circuit 32 in the next stage.
The amplitude value is retained. The held value is A /
The analog value is converted into a digital value by the D conversion circuit 33, and the converted digital value is output to the CPU 10.

The CPU 10 adjusts the RF signal amplitude to be added / subtracted from the output value of the A / D conversion circuit 33.
First electronic volume 12C, second electronic volume 1
As the 2D resistance value, a resistance value that minimizes the amount of the RF signal mixed is obtained. The resistance value thus obtained is used as the first electronic volume 12 in the wobble signal control means 12.
C, send a signal to the second electronic volume 12D,
The RF signal component mixed in the wobble signal is removed. Therefore, it is possible to detect the optimum wobble signal. The above operation is shown in the flow.

FIG. 9 is a flow chart showing the main processing flow when setting the RF signal amplitude to be added to or subtracted from the track error signal in the second embodiment of the invention. In the figure, # 11 to # 21 indicate steps.

In step # 11, the CPU 10 rotationally drives the spindle motor 2 by a pindle motor driver (not shown), turns on the semiconductor laser 27 by a driver circuit (not shown) of the semiconductor laser 27, and instructs the servo controller 9 to operate. Then, the focus control means 4 activates the focus servo. Step # 12
Then, the track control means 5 applies the track servo. In step # 13, the first analog switch 12A and the second analog switch 12B in the wobble signal control means 12 are turned on and the RF signal is turned on.
Set to the state of adding to the E signal.

In step # 14, the RF signal mixing amount detecting means (high pass filter 31, peak hold circuit 32,
The RF signal mixing amount is detected by the A / D conversion circuit 33). In step # 15, it is determined whether the RF signal mixing amount is the minimum. When the RF signal mixing amount is not the minimum, the process proceeds to step # 16, and the first electronic volume 12
The resistance value of C is incremented, and the process returns to step # 14.

When it is detected in step # 15 that the RF signal mixing amount has become minimum (when the RF signal is added to the TE signal), the process proceeds to step # 17. Step # 17
Then, the first analog switch 12A in the wobble signal control means 12 is turned off, and the second analog switch 12 is turned off.
B is set to the ON state, and the RF signal is set to the state where the RF signal is subtracted from the TE signal. In step # 18, the RF signal mixing amount detection means (including the high-pass filter 31, the peak hold circuit 32, and the A / D conversion circuit 33) detects the RF signal mixing amount.

At step # 19, it is determined whether the RF signal mixing amount is minimum. If the RF signal mixing amount is not the minimum, the process proceeds to step # 20 and the second electronic volume 12
The resistance value of D is incremented, and the process returns to step # 18. When it is detected in step # 19 that the RF signal mixing amount has become minimum (when the RF signal is subtracted from the TE signal), the process proceeds to step # 21. In step # 21, C
The PU 10 adds and subtracts the RF signal to and from the TE signal, resulting in R
The resistance value that minimizes the F signal mixing amount is set in the wobble signal control means 12, and the flow of FIG. 9 is terminated.

As described above, the RF signal mixing amount detecting means for detecting the mixing amount of the RF signal into the track error signal is provided, and the RF signal is subjected to the track error so as to minimize the mixing amount into the track error signal. Add or subtract signals. That is, in Step # 15 (when the RF signal is added to the TE signal) and Step # 19 (when the RF signal is subtracted from the TE signal) in FIG. 9, the two RF signal mixing amounts obtained are the minimum. The resistance values are compared with each other, and one of the addition resistance value and the subtraction resistance value is selected and set in the wobble signal control means 12. Therefore, according to the second embodiment (the invention of claim 3), the incidental information can be detected more accurately than in the case of the first embodiment (the optical disk device of claim 1). It will be possible.

Third Embodiment The third embodiment corresponds to the invention of claim 4, but is also related to the inventions of claims 1 to 3.
The object of the invention of claim 4 is to eliminate the influence of warpage or the like occurring on the optical disk, and it can be applied to all the inventions of claims 1 to 3 described so far.

The invention of claim 4 also has the same hardware configuration as the inventions of claims 1 to 3. This third
The embodiment (the invention of claim 4) is characterized in that the attenuation amount of the reproduction signal amplitude added to and subtracted from the track error signal is changed depending on the position of the optical disc in the radial direction.

FIG. 10 is a conceptual diagram showing an example of a state in which a warped optical disk is loaded in the apparatus. The reference numerals in the figure are the same as those in FIG. 1, and 3'denotes the moving position of the optical pickup 3.

Although the warp of the optical disc 1 is emphasized in FIG. 10, microscopically, almost all the optical discs 1 have such a tilt (tilt: hereinafter referred to as tilt). There is. Therefore, depending on the radial position of the optical disc 1, the amount of light incident on each of the light receiving elements 11A to 11D of the four-division light receiving element 11 of the optical pickup 3 is
As can be seen from FIG. 10, the reproduced signal R is mixed in the track error signal depending on the position of the disk.
The amount of F is different. Therefore, the CPU 10 needs to change the setting of the wobble signal control means 12 according to the position of the optical pickup 3, that is, the position in the radial direction of the disc.

In the optical disk device of FIG. 1, the CPU 1
0 drives the spindle motor 2 to rotate by a spindle motor drive (not shown). After that, the semiconductor laser 27 is turned on by a driver (not shown) of the semiconductor laser 27 and the servo controller 9 is instructed to perform the focus servo by the focus control means 4. After the focus servo is applied, the servo controller 9 is instructed and the track control means 5 applies the track servo.

The CPU 10 detects the radial position of the optical disc 1 in the track-on state. Next, CPU
When detecting a predetermined position (10-minute position, 30-minute position, 60-minute position in this example) 10, the RF signal mixing amount detection means (high-pass filter 31, peak hold circuit 32, A / D conversion circuit in FIG. 8). 33), the amount of the RF signal mixed in the wobble signal is measured.

Then, it is judged whether or not the RF signal mixing amount is the minimum, and the first electronic volume 12C or the second electronic volume in the wobble signal control means 12 is controlled so that the RF signal mixing amount is the minimum. Change the 12D settings. The resistance value that minimizes the mixing of the RF signal into the wobble signal is obtained and set in the wobble signal control means 12. Also in this case, the case of addition and the case of subtraction are compared, and the one (either addition or subtraction) that minimizes the RF signal mixing amount is selected.

Therefore, the attenuation amount of the RF signal amplitude to be added to or subtracted from the track error signal can be obtained according to the radial position on the optical disc 1. By performing such control, the wobble signal can be detected regardless of the tilt generated on the optical disc 1. The position in the radial direction can be detected by the wobble signal or by reproducing the subcode recorded on the optical disc 1 as the reproduction signal RF. The above operation is shown in the flow.

FIG. 11 is a flow chart showing the main processing flow when setting the attenuation amount of the RF signal amplitude to be added to and subtracted from the track error signal in the third embodiment of the invention. In the figure, # 31 to # 40 indicate steps.

This control is also performed by the CPU 10. In step # 31, the CPU 10 rotationally drives the spindle motor 2 by a spindle motor drive (not shown). After that, the semiconductor laser 27 is turned on by a driver (not shown) of the semiconductor laser 27 and the servo controller 9 is instructed to perform the focus servo by the focus control means 4.
In the next step # 32, the CPU 10 commands the servo controller 9 to apply the track servo by the track control means 5.

At step # 33, the CPU 10 detects the radial position on the optical disc 1 in the track-on state. In the next step # 34, the CPU 10 accesses a predetermined position (for example, a 10-minute position according to ISO).

When a predetermined position (for example, 10-minute position) is detected, the process proceeds to step # 35, and the CPU 10 causes the RF
Signal mixing amount detection means (composed of the high-pass filter 31, the peak hold circuit 32, and the A / D conversion circuit 33 in FIG. 8)
Then, the RF signal mixing amount of the wobble signal is measured.
In step # 36, it is determined whether or not the amount of mixed RF signals is minimum.

When the RF signal mixing amount is not the minimum value, the process proceeds to step # 37, and the first electronic volume 12C and the second electronic volume 12C in the wobble signal control means 12 are set so that the RF signal mixing amount is minimized. The setting of the electronic volume 12D is changed. Then, when it is detected in step # 36 that the RF signal mixing amount is the minimum value, step # 38
Proceed to.

In step # 38, the set value that minimizes the amount of the RF signal mixed into the wobble signal is set in the wobble signal control means 12, and the process returns to step # 33. Further, as a result of accessing in the previous step # 34, when a predetermined position (for example, a 10-minute position by ISO) cannot be detected, the process proceeds to step # 39, and another predetermined position (for example, a 30-minute position) is accessed. .

When a predetermined position (for example, 30 minutes position) is detected, the process proceeds to step # 35 and the same processing is performed as in the previous case, and when it cannot be detected, the process proceeds to next step # 40. Go to another predetermined position (for example, 60
Minute position). Also in this case, when the predetermined position (for example, 60-minute position) is detected, the process proceeds to step # 35 as in the previous case, but when it is not detected, the process returns to the previous step # 33 again. Therefore, it is possible to detect the incidental information more accurately as compared with the optical disc device according to the first aspect. Through the above processing, a set value (for example, a resistance value) that minimizes the mixing amount of the RF signal into the wobble signal is obtained for each predetermined position (10-minute position, 30-minute position, and 60-minute position in this example). To be

Therefore, at the time of subsequent access, when the radial position on the optical disk 1 reaches a predetermined value (here, 10 minutes, 30 minutes, 60 minutes according to ISO),
By the method as described in the first embodiment, the wobble signal control means 12 attenuates the reproduction signal and adds / subtracts to / from the track error signal, and the track error signal arithmetic circuit 5a.
The wobble signal is detected from the output of. Therefore, according to the third embodiment (the invention of claim 4), the wobble signal can be detected regardless of the tilt of the optical disc 1. That is, the influence of the warp or the like of the optical disc is removed, and the incidental information can be accurately detected.

Fourth Embodiment The fourth embodiment corresponds to the invention of claim 5, but is also related to the inventions of claims 1 to 4.
In the above-mentioned optical disk devices according to claims 1 to 4, no limitation is set on the amplitude of the reproduction signal RF that is added to or subtracted from the track error signal TE. However, when the track error signal operation circuit 5a is composed of an operational amplifier, the signal amplitude input to the operational amplifier is limited by the power supply of the operational amplifier and the dynamic range is restricted by the power supply voltage and the like.

In this case, the reproduction signal R having a large signal amplitude
When F is added to or subtracted from the track error signal TE, the original purpose of the wobble signal control means 12 is to "prevent mixing of the reproduced signal RF by adding and subtracting the reproduced signal RF to an optimum level to the track error signal TE". There is a problem that you can not do it. In the fourth embodiment (the invention of claim 5), the reproduction signal R of a certain value or less is used.
By adding and subtracting F to the track error signal TE,
It is characterized in that the auxiliary information can be accurately detected by always operating within the dynamic range of the track error signal calculation circuit 5a.

FIG. 12 is a circuit diagram showing an example of a detailed configuration of the preamplifier section 7, the wobble signal control means 12, the track error signal operation circuit 5a and its peripheral circuits shown in FIGS. 2 and 3. Is. Reference numerals in the drawings are the same as those in FIGS. 2 and 3, and 41 is the first RF.
A signal amplitude limiting resistor, 42 is a second RF signal amplitude limiting resistor.

In the circuit shown in FIG. 12, the track error signal TE is used in the track error signal operation circuit 5a.
A first RF signal amplitude limiting resistor 41 for limiting the RF signal amplitude when adding the RF signal to the second and a second RF signal amplitude limiting resistor for limiting the RF signal amplitude when subtracting the RF signal from the track error signal. RF signal amplitude limiting resistor 42
Shows the state where and are added. As described above, when the track error signal operation circuit 5a is composed of an operational amplifier, the signal amplitude input to the operational amplifier is
Limited by the power supply of the operational amplifier. For example, when the first electronic volume 12C has a value smaller than a certain resistance value, R is determined by the gain determined by the ratio with the feedback resistance of the operational amplifier in the track error signal operation circuit 5a.
The F signal is attenuated.

However, by providing the first RF signal amplitude limiting resistor 41 between the first electronic volume 12C and the operational amplifier, the RF signal amplitude becomes the TE signal by the amplitude determined by the following equation. Will be added. (TE) = {(Rfb) × (RF)} / {(R12C)
+ (R41)} TE: TE signal addition signal Rfb: Feedback resistance value of operational amplifier RF: RF signal amplitude R12C: Resistance value of first electronic volume 12C R41: Resistance value of first RF signal amplitude limiting resistor 41

That is, even if the resistance value of the first electronic volume 12C is set small, the inconvenience that the first RF signal amplitude limiting resistor 41 adds the RF amplitude of a certain value or more does not occur. Second electronic volume 1
The same applies when 2D becomes smaller than a certain resistance value.
The RF signal amplitude limiting resistor 42 does not subtract the RF amplitude above a certain value.

Although a hardware embodiment is shown in FIG. 12, a non-volatile memory (not shown) is provided in the CPU 10, and the non-volatile memory includes a first electronic volume 12C and a second electronic volume. The lower limit value of 12D is stored. Then, when setting the resistance values of the first electronic volume 12C and the second electronic volume 12D, the CPU 10 may not set the resistance values below the lower limit value stored in the nonvolatile memory. As described above, in the fourth embodiment, the amount of attenuation of the RF signal amplitude that is added to or subtracted from the track error signal is limited, and the reproduction signal RF having a fixed value or less is added to or subtracted from the track error signal TE. There is. Therefore, it becomes possible to always operate within the dynamic range of the track error signal calculation circuit 5a, and the incidental information can be accurately detected.

Fifth Embodiment The fifth embodiment corresponds to the invention of claim 6 but is also related to the inventions of claims 1 to 5.
The amount of the RF signal mixed in the track error signal greatly changes due to variations in the optical disc as well as variations in the optical disc device. In the optical disk device according to claims 1 to 5, when the optical disks are replaced,
In some cases, the incidental information cannot be accurately detected. In the fifth embodiment (the invention of claim 6), in the optical disk device of claims 1 to 5, when the power is turned on or the optical disk is inserted, the attenuation amount of the RF signal amplitude to be added / subtracted to / from the track error signal is reproduced. It has a feature in adjusting.

FIG. 13 is a diagram showing an example of an embodiment of the main configuration of an optical disc insertion detecting section in the optical disc device of the present invention. (1) is a functional block diagram and (2) is a structural diagram. Reference numerals in the figure are the same as those in FIG. 1, 51 is a signal line, 52 is a media-in switch, and 53 is a drive housing.

As shown in FIGS. 13 (1) and 13 (2), a media-in switch 52 is provided, which is pushed by the optical disc 1 and is turned on when the optical disc 1 is inserted into the drive housing 53. This media-in switch 52
When is turned on, the signal line 51 changes to L level, for example. When the CPU 10 detects this state, it is determined that the optical disc 1 has been inserted.

Then, at this time, in order to remove the RF signal mixed in the wobble signal by the wobble signal control means 12, a process of adding or subtracting the RF signal to or from the track error signal, that is, an RF signal to be added or subtracted from the track error signal. Adjust the amplitude attenuation. Instead of adjusting the attenuation amount of the RF signal amplitude using the media-in switch 52, it is also possible to perform the adjustment together with the reset generation of the CPU 10 when the power is turned on. Next, the above operation will be described with a flow.

FIG. 14 is a flow chart showing the main processing flow at the time of readjustment of the attenuation amount of the RF signal amplitude added to and subtracted from the track error signal in the fifth embodiment of the invention. In the figure, # 41 to # 42 indicate steps.

At step # 41, it is checked whether or not an optical disk is inserted (it is also possible to check whether or not the power is turned on). When it is detected that an optical disc has been inserted, the process proceeds to step # 42, the RF signal is attenuated, the track error signal is added / subtracted, the attenuation amount of the RF signal amplitude is readjusted, and the flow of FIG. 14 is ended.

As described above, in the fifth embodiment, the CPU 10 performs the R after the optical disc 1 is inserted.
The F signal is attenuated and added to or subtracted from the track error signal.
Therefore, the incidental information can be accurately detected regardless of variations in the optical disc.

Sixth Embodiment The sixth embodiment corresponds to the invention of claim 7, but is also related to the inventions of claims 1 to 6.
In the optical disk device according to any one of claims 1 to 6, when the warp of the disk changes due to a temperature change or the like, or the mixing amount of the reproduction signal changes due to the temperature characteristic of the optical system,
The incidental information cannot be detected accurately. In the sixth embodiment (the invention of claim 7), in the optical disk device according to claims 1 to 6, a temperature detecting means is provided, and the reproduction signal is attenuated again by the temperature change, and the track error signal is added / subtracted. The feature is that it does.

FIG. 15 is a functional block diagram showing an example of an embodiment of the main configuration of the temperature detecting section in the optical disk device of the present invention. The reference numerals in FIG.
61 is a temperature sensor, 62 is a resistor, and 63 is
Indicates a buffer amplifier, 64 indicates an A / D conversion circuit, and X indicates a point on the signal line.

The temperature sensor 61 is a sensor for detecting the temperature of the optical disk device (drive), and is a thermistor whose resistance value changes according to the temperature. For example,
The thermistor is an element whose resistance value decreases as the temperature rises and conversely increases as the temperature falls.

In FIG. 15, the temperature sensor 61 is connected in series with the resistor 62 and is lowered to the GND level. By connecting in this way, one point X on the signal line
Voltage varies with temperature changes. The voltage at the point X is buffered by the buffer amplifier 63 in the next stage and output to the A / D conversion circuit 64 in the next stage. The buffer amplifier 63 is inserted to reduce the error in the detected temperature due to the input current required by the A / D conversion circuit 64.

The A / D conversion circuit 64 converts the detected analog voltage value into a digital value and outputs it to the CPU 10. When the CPU 10 detects a temperature change based on the output from the temperature detector of FIG. 15, the CPU 10 adjusts the attenuation amount of the RF signal amplitude that is added to or subtracted from the track error signal at that time. The above operation will be described with a flow.

FIG. 16 is a flow chart showing the main processing flow at the time of readjustment of the attenuation amount of the RF signal amplitude added to and subtracted from the track error signal in the sixth embodiment of the invention. In the figure, # 51 to # 53 indicate steps.

At step # 51, the CPU 10 detects the temperature inside the drive by the output of the A / D conversion circuit 64. In step # 52, the CPU 10 again detects the temperature by the output of the A / D conversion circuit 64, and checks whether the difference from the temperature at the previous detection is a predetermined value or more.

When the difference from the temperature at the previous detection is equal to or more than the predetermined value, the process proceeds to step # 53, the RF signal is attenuated, and the track error signal is added / subtracted, and this FIG.
Ends the flow. As described above, the CPU 10 detects the temperature inside the drive by the output of the A / D conversion circuit 64, detects the temperature again by the A / D conversion circuit 64, and outputs the RF signal only when the temperature difference occurs. Is attenuated and added to or subtracted from the track error signal. Therefore, the influence of the temperature change is removed, and the incidental information can be accurately detected.

Seventh Embodiment The seventh embodiment corresponds to the invention of claim 8 but is also related to the inventions of claims 1 to 7.
In the sixth embodiment (the invention of claim 7), the attenuation of the reproduction signal added to and subtracted from the track error signal is readjusted due to the temperature change, but the passage of time is not taken into consideration. The seventh embodiment (the invention of claim 8) is characterized in that more accurate detection of incidental information can be performed by re-adjusting the attenuation amount of the reproduction signal due to the change over time as well as the temperature change. have.

FIG. 17 is a functional block diagram showing an example of an embodiment of the configuration of the main part of the timer section of the optical disk device of the present invention. The reference numerals in FIG.
And 71 indicates a timer circuit.

In FIG. 17, the timer circuit 71
This is a circuit that outputs a time signal to the CPU 10 at regular time intervals. The timer circuit 71 may be a counter composed of a flip-flop and an oscillator, or may be a timer LSI as long as it is a type that outputs a signal at regular time intervals. When the CPU 10 receives the signal from the timer circuit 71, the CPU 10 readjusts the attenuation amount of the RF signal amplitude to be added / subtracted from the track error signal by the above-mentioned arbitrary method. The above operation will be described with a flow.

FIG. 18 is a flow chart showing the main processing flow at the time of readjustment of the attenuation amount of the RF signal amplitude which is added to or subtracted from the track error signal in the seventh embodiment of the invention. In the figure, # 61 to # 62 indicate steps.

At step # 61, the CPU 10 checks the presence / absence of a signal from the timer circuit 71. When the signal from the timer circuit 71 is received, in step # 62, the attenuation amount of the RF signal amplitude that is added to or subtracted from the track error signal is readjusted.

In the seventh embodiment, as described above, when the signal indicating the elapse of a certain time is output from the timer circuit 71, the CPU 10 resets the attenuation amount of the RF signal amplitude to be added to or subtracted from the track error signal. adjust. That is, in the disk device of claim 8, in the optical disk device of claims 1 to 7, the attenuation amount of the RF signal amplitude to be added / subtracted to / from the track error signal is readjusted according to time change. Therefore, the influence of the mixing amount of the RF signal of the track error signal due to the passage of time is removed, and the incidental information can be accurately detected. In addition, if the readjustment interval is sufficiently short, the effect of temperature change is also removed.

Eighth Embodiment The eighth embodiment corresponds to the invention of claim 9, but is also related to the inventions of claims 1 to 8.
The eighth embodiment (the invention of claim 9) is characterized by the timing of readjusting the attenuation amount of the RF signal amplitude that is added to or subtracted from the track error signal.

FIG. 19 is a functional block diagram showing an example of the embodiment of the system configuration to which the optical disk device of the present invention is connected. The reference numerals in FIG.
81 is an initiator, 82 is a SCSI interface device, and 83 is a SCSI controller.

In FIG. 19, the initiator 81
Is a device that issues a command to an optical disk device (not shown), for example, a host computer. The initiator 81 issues a command for recording or reproducing data to the SCSI controller 83 via the SCSI interface device 82, and the SCSI (small computer system interface) controller 83
Informs the CPU 10 of the content of the command.

If the received command is a command for recording / reproducing information on the optical disk, the CPU 10 adds / subtracts to / from the track error signal by the method described above.
Readjust the F signal amplitude. Such an operation is performed when the interface device is SCSI, but it is the same when other interface devices are used.

In FIG. 19, when the CPU 10 receives a command for recording or reproducing on the optical disc 1 from the initiator 81, it re-adjusts the attenuation amount of the RF signal amplitude which is added to or subtracted from the track error signal. The above operation is shown by a flow.

FIG. 20 is a flow chart showing the main processing flow at the time of readjustment of the attenuation amount of the RF signal amplitude which is added to or subtracted from the track error signal in the eighth embodiment of the invention. In the figure, # 71 to # 72 indicate steps.

This control is also performed by the CPU 10. In step # 71, the CPU 10 causes the initiator 8
It is monitored whether or not the command for recording or reproducing from the optical disc 1 is received from the device 1. When the command is received, in the next step # 72, the RF signal amplitude to be added to or subtracted from the track error signal is readjusted, and the flow of FIG. 20 is ended.

As described above, in the eighth embodiment (the invention of claim 9), the track error signal is output immediately before the data recording or reproducing operation in the optical disk device of claims 1 to 8. The amount of attenuation of the RF signal amplitude to be added and subtracted is readjusted. Therefore, it is always possible to accurately detect the incidental information.

Ninth Embodiment This ninth embodiment corresponds to the invention of claim 10 but is also related to the invention of claim 3. The ninth embodiment (the invention of claim 10) is characterized in that the attenuation amount of the RF signal amplitude which is added to or subtracted from the track error signal is set quickly.

FIG. 21 is a functional block diagram showing an example of an embodiment of the main configuration of the optical disk device of the present invention. Reference numerals in the drawings are shown in FIG. 1, FIG. 2 and FIG.
91 is a non-volatile memory.

In FIG. 21, the nonvolatile memory 91
Is the resistance value and RF of the first electronic volume 12C and the second electronic volume 12D in the wobble signal control means 12.
It is a storage unit that stores the relationship with the signal mixing amount. The configuration other than the nonvolatile memory 91 is the same as that of FIG. 1 described in the first and second embodiments.

FIG. 22 is a diagram showing an example of the parameters stored in the non-volatile memory 91.

The CPU 10 determines the amount of the RF signal mixed into the high pass filter 31, peak hold circuit 32, A /
It is detected by the D conversion circuit 33. RF signal mixing amount is 2
When it is 0 mVpp, the resistance value of the first electronic volume 12C and the second electronic volume 12D is set to 270 KΩ to reduce the attenuation rate of the RF signal amplitude to be added and subtracted. Also, when the RF signal mixing amount is 10 mVpp,
First electronic volume 12C, second electronic volume 1
By setting the 2D resistance value to 330 KΩ, the attenuation rate of the RF signal amplitude to be added / subtracted is increased. Thus, by determining the attenuation rate of the RF signal amplitude to be added / subtracted according to the amount of the RF signal mixed in the track error signal, high speed processing becomes possible.

FIG. 23 is a flow chart showing the main processing flow at the time of readjustment of the attenuation amount of the RF signal amplitude added to and subtracted from the track error signal in the ninth embodiment of the invention. In the figure, # 81 to # 84 indicate steps.

In step # 81, the CPU 10 rotationally drives the spindle motor 2 by a spindle motor drive (not shown). After that, the semiconductor laser 27
Semiconductor laser 27 by a driver (not shown) of
Is turned on and a focus servo is applied by the focus control means 4 by instructing the servo controller 9. In the next step # 82, the CPU 10 commands the servo controller 9 to apply the track servo by the track control means 5.

At step # 83, the CPU 10 measures the RF signal mixing amount of the wobble signal by the RF signal mixing amount detecting means (comprising the high pass filter 31, the peak hold circuit 32 and the A / D conversion circuit 33 of FIG. 8). . In step # 84, the RF signal is attenuated according to the parameters stored in the non-volatile memory 91 to be added / subtracted from the track error signal, and the flow of FIG. 23 is ended.

Through the above processing, the CPU 10 measures the RF signal mixing amount of the wobble signal. When the RF signal mixing amount of the wobble signal is detected, the RF signal mixing amount stored in the nonvolatile memory 91 and the first electronic volume 12 are stored.
The first electronic volume 12C and the second electronic volume 12D are set from the parameters such as C and the resistance value of the second electronic volume 12D, and the RF signal is added or subtracted. Therefore, it is possible to set the wobble signal control means at a higher speed than in the optical disk device according to the third aspect.

[0127]

According to the optical disk device of the first aspect of the present invention, the wobble signal is detected from the output of the track error signal arithmetic circuit by attenuating the reproduction signal, adding and subtracting the track error signal. Therefore, even if the reproduction signal is mixed in the track error signal, it is possible to reduce the mixing of the reproduction signal in the track error signal with an inexpensive configuration that does not require addition of a special circuit. Information can be detected.

According to the optical disk device of the second aspect, the first aspect
In the optical disc device, the wobble signal control means is
Two analog switches and analog switch on / off
It is composed of an inverter that switches off and two electronic potentiometers. Therefore, it is possible to reduce the mixing of the track error signal in the reproduction signal with a low-cost and simple circuit configuration, and it is possible to accurately detect the incidental information.

According to the optical disc device of claim 3,
In the optical disc device, the RF signal mixing amount detection means is provided, and the reproduction signal is added to or subtracted from the track error signal so that the mixing amount of the RF signal into the track error signal is minimized. Therefore, it is possible to detect the incidental information more accurately as compared with the optical disc device according to the first aspect.

According to the optical disc device of claim 4,
Therefore, in the optical disc apparatus according to the third aspect, when the reproduction signal is attenuated and added to or subtracted from the track error signal, the position is changed depending on the radial position of the optical disc. Therefore, the influence of the warp of the optical disc is removed, and the incidental information can be accurately detected.

According to the optical disk device of claim 5,
Therefore, in the optical disk device according to the fourth aspect, the RF signal amplitude to be added / subtracted to / from the track error signal is limited, and the reproduction signal having a predetermined amplitude or less is added / subtracted to / from the track error signal. Therefore, in addition to the effects of the optical disk device according to the first to fourth aspects, the optical disc apparatus can be operated within the dynamic range of the track error signal arithmetic circuit, and the incidental information can be accurately detected.

According to the optical disk device of claim 6,
Therefore, in the optical disk device according to the fifth aspect, when the power is turned on or when the optical disk is inserted, the reproduction signal is attenuated and added to or subtracted from the track error signal. Therefore, in addition to the effects of the optical disk device according to the first to fifth aspects, the incidental information can always be accurately detected regardless of the variation of the optical disk.

According to the optical disk device of the seventh aspect, the first aspect
Therefore, in the optical disk device according to the sixth aspect, the reproduction signal is attenuated again by the temperature change, and the track error signal is added or subtracted. Therefore, in addition to the effects of the optical disk device according to the first to sixth aspects, the influence of the temperature change is removed, and the incidental information can be accurately detected.

According to an eighth aspect of the present invention, in the optical disc apparatus according to the first to seventh aspects, the attenuation amount of the reproduction signal amplitude to be added to or subtracted from the track error signal is readjusted according to the time change. Therefore, in addition to the effects of the optical disk device according to the first to seventh aspects, the influence of the RF signal mixing amount of the track error signal due to the passage of time is removed, and the accurate incidental information can be detected. In addition, if the readjustment interval is sufficiently short, the effect of temperature change can be eliminated.

According to a ninth aspect of the present invention, in the optical disc apparatus according to the first to eighth aspects, the attenuation amount of the RF signal amplitude to be added to or subtracted from the track error signal is readjusted immediately before the data recording or reproducing operation. There is. Therefore, in addition to the effects of the optical disk device according to the first to eighth aspects, it is possible to always accurately detect the incidental information.

According to the disk device of claim 10, claim 3
In the optical disc device, the storage means for storing the parameters of the relationship between the mixing amount of the RF signal and the attenuation rate of the RF signal amplitude when the reproduction signal is added or subtracted is provided, and the CPU is the RF.
When the amount of mixed signals is detected, the reproduced signal is attenuated according to the parameter stored in the storage means, and added or subtracted from the track error signal. Therefore, claim 3
In addition to the effect of the optical disc device, the wobble signal control means can be set at high speed.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing an example of an embodiment of a main configuration of an optical disc device of the present invention.

FIG. 2 is a circuit diagram showing an example of an embodiment of a detailed configuration of an RF signal generation circuit around the RF signal arithmetic circuit 8 of FIG.

FIG. 3 is a diagram showing an example of an embodiment of a detailed configuration of the wobble signal control means 12 in FIG.

FIG. 4 is an exploded perspective view showing a main structure of an optical system provided inside the optical pickup 3.

5 is a diagram showing a configuration of a main part of an optical system of the optical pickup 3 shown in FIG.

FIG. 6 is a flowchart showing a main processing flow at the time of redetection of incidental information of an optical disc in the first embodiment of the present invention.

FIG. 7 is a diagram illustrating a waveform in a state where a reproduction signal RF is mixed in a wobble signal.

FIG. 8 is a functional block diagram showing an example of an embodiment of an RF signal mixing amount detection circuit for extracting a reproduction signal RF mixed in a wobble signal in the optical disc device of the present invention.

FIG. 9 is a flowchart showing a main processing flow when setting an RF signal amplitude to be added to or subtracted from a track error signal in the second embodiment of the invention.

FIG. 10 is a conceptual diagram showing an example of a state in which a warped optical disk is loaded in the apparatus.

FIG. 11 is a flowchart showing the main processing flow when setting the attenuation amount of the RF signal amplitude to be added to or subtracted from the track error signal in the third embodiment of the invention.

FIG. 12 is a circuit diagram showing an example of a detailed configuration of the preamplifier section 7, wobble signal control means 12, track error signal operation circuit 5a and peripheral circuits thereof shown in FIGS. 2 and 3.

FIG. 13 is a diagram showing an example of an embodiment of a main part configuration of an optical disc insertion detection unit in the optical disc device of the present invention.

FIG. 14 is a flowchart showing a main processing flow at the time of readjustment of the attenuation amount of the RF signal amplitude added to and subtracted from the track error signal in the fifth embodiment of the invention.

FIG. 15 is a functional block diagram showing an example of an embodiment of a main configuration of a temperature detecting section in the optical disk device of the present invention.

FIG. 16 is a flow chart showing a main processing flow at the time of readjustment of the attenuation amount of the RF signal amplitude which is added to or subtracted from the track error signal in the sixth embodiment of the invention.

FIG. 17 is a functional block diagram showing an example of an embodiment of a main part configuration of a timer unit using a timer in the optical disc device of the present invention.

FIG. 18 is a flowchart showing a main processing flow at the time of readjustment of the attenuation amount of the RF signal amplitude which is added to or subtracted from the track error signal in the seventh embodiment of the invention.

FIG. 19 is a functional block diagram showing an example of the embodiment of the configuration of the system to which the optical disk device of the present invention is connected.

FIG. 20 is a flow chart showing the main processing flow when readjusting the attenuation amount of the RF signal amplitude that is added to or subtracted from the track error signal in the eighth embodiment of the present invention.

FIG. 21 is a functional block diagram showing an example of an embodiment of the main configuration of the optical disc device of the present invention.

22 is a diagram showing an example of parameters stored in a nonvolatile memory 91. FIG.

FIG. 23 is a flowchart showing a main processing flow when readjusting the attenuation amount of the RF signal amplitude to be added to or subtracted from the track error signal in the ninth embodiment of the invention.

[Explanation of symbols]

 4 Focus Control Means 4a Focus Error Signal Calculation Circuit 5 Track Control Means 5a Track Error Signal Calculation Circuit 6 Carriage Servo Means 7 Preamplifier 7A-7D I / V Converter 8 RF Signal Calculation Circuit 9 Servo Controller 10 CPU 11 4 Divided Light-Receiving Element 12 wobble signal control means 12A first analog switch 12B second analog switch 12C first electronic volume 12D second electronic volume 12E inverter 31 high-pass filter 32 peak hold circuit 33 A / D conversion circuit 91 non-volatile memory

Claims (10)

[Claims] 1. An optical disc comprising: a focus control unit for focusing a light beam from a semiconductor laser on an optical disc by an objective lens; a track control unit; and a carriage servo unit for moving the objective lens in a radial direction of the optical disc. An optical disc device that detects a reproduction signal on a track by detecting the incidental information of an optical disc on which track wobble recording is performed by causing the luminous flux to follow the upper track. A plurality of track light-receiving elements for detecting an error, an I / V conversion circuit for converting the output from the track light-receiving element into a current / voltage, and a track error signal for generating a track error signal based on a difference between the outputs from the I / V conversion circuit Reproduction by the sum of the output from the signal operation circuit and the I / V conversion circuit An optical disc device having a reproduction signal operation circuit for generating a signal, the wobble signal control means for attenuating the reproduction signal to add / subtract the track error signal, and a CPU for controlling the wobble signal control means, The optical disk device, wherein when the incidental information of the optical disk cannot be detected, the CPU attenuates the reproduction signal to add / subtract the track error signal, and detects a wobble signal from the output of the track error signal calculation circuit. 2. The optical disk device according to claim 1, wherein the wobble signal control means includes first and second analog switches connected to a reproduction signal, and the first and second analog switches according to a signal from a CPU. An inverter for switching ON / OFF, a first electronic volume connected to the first analog switch for attenuating a reproduction signal and adding it to a track error signal, and an electronic volume connected to the second analog switch. An optical disc device comprising: a second electronic volume for attenuating a reproduction signal and subtracting it from a track error signal. 3. The optical disk device according to claim 1, further comprising a reproduction signal mixture amount detection means for detecting a mixture amount of the reproduction signal into the track error signal, wherein an attenuation amount of a reproduction signal amplitude to be added to or subtracted from the track error signal is An optical disk device, characterized in that the reproduction signal is determined so as to be minimally mixed with a track error signal in a track-on state. 4. The optical disk device according to any one of claims 1 to 3, wherein an attenuation amount of a reproduction signal amplitude which is added to or subtracted from the track error signal is changed depending on a radial position of the optical disk. 5. The optical disk device according to any one of claims 1 to 4, wherein a limit is set on an attenuation amount of a reproduction signal amplitude which is added to or subtracted from the track error signal. 6. The optical disk device according to claim 1, wherein the reproduction signal is attenuated and added to or subtracted from the track error signal when the power is turned on or when the optical disk is inserted. 7. The optical disk device according to any one of claims 1 to 6, further comprising: temperature detecting means, wherein the reproduced signal is attenuated again by the temperature change and the track error signal is added or subtracted. 8. The optical disk device according to any one of claims 1 to 7, wherein the attenuation amount of the reproduction signal amplitude to be added to or subtracted from the track error signal is readjusted at a predetermined time interval. 9. The optical disk device according to any one of claims 1 to 8, wherein the attenuation amount of the RF signal amplitude to be added to or subtracted from the track error signal is readjusted immediately before the data recording or reproducing operation. . 10. The optical disk device according to claim 3, further comprising a storage unit that stores a parameter for the relationship between the reproduction signal mixing amount and the attenuation rate of the reproduction signal amplitude when the reproduction signal is added or subtracted. An optical disk device, characterized in that, when a mixing amount is detected, a reproduction signal is attenuated according to a parameter stored in the storage means to be added to or subtracted from a track error signal.