JPH11353666A - Optical disk automatic adjusting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the tracking balance deviation after an AB gain adjustment by avoiding an AB gain adjustment in a condition where the tracking balance is deviated. SOLUTION: The automatic adjusting device is provided with an offset compensating means 15 which compensates the offset of tracking error signals, a tracking balance adjusting means 18 which adjusts the balance of the output signals of the means 15, a tracking balance deviation detecting means 17 which detects the deviation of the tracking balance from a reference voltage, and a coefficient adjusting means 21 which adjusts a coefficient K so as to eliminate the offset of tracking error signals while an objective lens 4 is shifted to a prescribed position. A tracking balance adjustment is conducted while no voltage is applied, to a tracking actuator 5. Then, the voltage which shifts the lens 4 from an objective lens driving means 20, is applied to the actuator 5, the coefficient K is adjusted and an AB gain automatic adjustment is conducted. Then, a tracking balance adjustment is conducted again and the deviation in the tracking balance is minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic optical disk adjusting device for detecting and correcting a tracking error (hereinafter abbreviated as TE) in an optical disk device.

[0002]

2. Description of the Related Art Optical discs have been put into practical use and spread as digital information media in the age of digital information. CDs (Compact Discs), LDs (Laser Discs), MDs (M
Ini Discs), DVDs (Digital Video Discs) and the like are now indispensable.

As a tracking detection method of this optical disk device, a one-beam method called a push-pull (hereinafter, referred to as PP) method is known. This method is simpler in structure than the three-beam method, and has a high use efficiency of the laser light amount, so that it is suitable for a recordable optical disk device requiring a large laser output. However, when the objective lens is displaced in a direction substantially perpendicular to the track, a problem arises in that an offset occurs in the TE signal, and a traverse mechanism capable of high-speed response is required for removing the offset, thereby causing an increase in cost.

[0004] An improved PP (hereinafter referred to as APP) method for reducing the offset of the TE signal when the objective lens is displaced has been proposed.

[0005] With respect to the prior art relating to the APP method, see, for example, Japanese Patent Application No. 9-194895 and Japanese Patent Application No. 8-2.
There is a technique described in 8905 specification and the like. T below
A conventional optical disk automatic adjustment device using the APP method for E detection will be described.

FIG. 9 is a block diagram of a conventional automatic optical disk adjusting apparatus using the APP method.
Is a turntable for fixing the optical disc 1, 3 is a motor for rotating the optical disc 1, 4 is an objective lens for condensing the light beam on the recording surface of the optical disc 1, and condensing the reflected light. Is a tracking actuator for displacing the objective lens 4 in a direction substantially perpendicular to the track so that the light beam follows an information track on the optical disk 1. A tracking actuator 6 performs phase compensation, low-frequency compensation, and the like on the TE signal. A tracking control means constituting a control system, 7 is a light spot where the reflected light from the optical disc 1 is condensed by the objective lens 4, 8 is a light spot 7 which is reflected on the recording surface of the optical disc 1 without diffracting.
An area (hereinafter referred to as a push-pull area) where the light spot of the next-order diffracted light and the ± 1st-order diffracted light diffracted and reflected by the track shape on the recording surface of the optical disc 1 cause interference (hereinafter referred to as a push-pull area), and 9 receives the light spot 7 A light receiving element 10 composed of a plurality of light receiving cells is a dividing line that divides the light receiving element 9 into a plurality of light receiving cells substantially perpendicularly to a direction corresponding to a track, and 11 is a light emitting element 9 corresponding to a track. This is a dividing line that divides the light receiving cell into a plurality of light receiving cells substantially parallel to the direction of the light receiving cell. A, B, C, and D are division line 10 and division line 1
The light-receiving cells A and B receive light in an end region with respect to the center of the light spot 7, and the light-receiving cells C and D are light-centered with respect to the center of the light spot 7. Receive the light in the area.

Reference numeral 12 denotes a light receiving cell B from the output of the light receiving cell A.
The light spot displacement detecting means 13 for calculating the relative displacement in the direction substantially perpendicular to the track of the light spot 7 on the light receiving element 9 by taking the difference between the end areas by subtracting the output of TE detection means for subtracting the output of the cell B to obtain the difference in the middle area, detecting the relative displacement between the light beam condensed on the disk recording surface and the information track, and outputting a TE signal; Amplifying means 15 for weighting the output signal of the displacement detecting means 12 and having an amplification factor K times (K is a coefficient) subtracts the output of the amplifying means 14 from the output of the TE detecting means 13 to correct the offset of the TE signal. This is the offset correction means to be performed.

The operation of the conventional optical disk automatic adjusting apparatus having the above-described configuration will be described with reference to FIGS.
This will be described with reference to FIGS.

FIG. 2 is a diagram showing the relative positional relationship between the light spot 7 of the reflected light from the disk and the light receiving element 9. FIG. 2A shows that the displacement of the objective lens 4 corresponds to the center of the optical axis of the light beam. FIG. 2B shows a case where the displacement of the objective lens 4 deviates from the center of the optical axis of the light beam to the inside of the disc, and FIG. 2C shows a case where the displacement of the objective lens 4 is light. This shows a case where the beam deviates from the optical axis center to the outside of the disk.
In the graph of FIG. 2D, the vertical axis indicates the DC component (hereinafter, referred to as DC component) of the light amount of each of the light receiving cells A, B, C, and D of the light receiving element 9, and the horizontal axis indicates the objective. Lens 4
, The amount of displacement of the objective lens 4 (hereinafter referred to as lens shift).

FIG. 3 shows the DC component of the uncorrected TE (= CD) signal output by the TE detection means 13 in FIG. 9, that is, the offset component of the output signal of the TE detection means 13. Further, by multiplying the output of the light spot displacement detecting means 12 by the coefficient K of the amplifying means 14, the K (A−B) signal which is a component for removing the offset of TE is amplified by the amplifying means 1.
4 is output. At this time, the coefficient K is multiplied by AB so that the offset of the CD signal becomes zero.

FIG. 4 shows the offset correction means 1 shown in FIG.
5 shows an output signal. As shown in FIG.
Is varied, the offset of the TE signal varies. At this time, TE, which is the output of the TE detection means 13,
The output signal of the offset correcting means 15, which is a means for subtracting the output of the amplifying means 14 from the signal, is called a TE1 signal.

When the relative position between the light beam and the track changes, the zero-order light in the push-pull region 8 in FIG.
Since the manner of interference of the next light changes, the difference component (CD component of the light receiving cell 9) in the middle region changes in a sine wave shape as shown by a broken line in FIG. A TE signal containing a push-pull component is obtained. At this time, the sine wave rotates 360 degrees in phase by one track movement. Further, in the end region, since the interference between the 0th order light and the ± 1st order light does not occur, the difference component (AB component of the light receiving cell 9) of the end region does not generate a sine wave as shown in FIG.

When the displacement of the objective lens 4 coincides with the optical axis of the light beam, that is, when the lens shift amount is 0,
Since the light spot 7 is located at the center of the light receiving element 9 as shown in FIG. 2A, the dashed waveform in FIG. , The K (AB) signal which is a difference signal in the end region is almost 0.
Becomes

When the irradiation position of the light beam is shifted from the optical axis by shifting the lens, the relative displacement between the light spot 7 and the light receiving element 9 is substantially perpendicular to the track as shown in FIGS. 2 (a) and 2 (b). Therefore, the difference signal in the middle area is a signal obtained by adding an offset corresponding to the lens shift amount to the TE signal as shown by a sine wave-shaped broken line in FIG. The difference signal in the end region can be considered as an offset removal signal corresponding to the displacement of the objective lens as indicated by K (AB).
By varying the value of K as shown in FIG. 4, it is possible to generate a TE1 signal such that the offset amount becomes zero. A method of changing the value of K so as to minimize the balance when the lens is shifted at this time and removing the offset of the TE1 signal is referred to as AB gain adjustment.

[0015]

However, there is a case where the position of the objective lens 4 is deviated from the center of the optical axis of the light beam even though the objective lens 4 is not displaced and the lens shift amount is 0 in FIG. is there. This is related to the assembly accuracy of the optical pickup. That is, to match the center of the objective lens 4 with the center of the optical axis of the light beam,
There is a problem that these centers must be adjusted with an accuracy of several tens of microns (μm). Considering these adjustments, it can be said that cost and time are difficult. Therefore, in order to avoid AB gain adjustment in the presence of an offset component, it is necessary to accurately perform offset removal at a position where the lens is not shifted before performing AB gain adjustment.

Before the AB gain adjustment is performed, not only when there is an offset component at a position where the lens center is 0, but also when there is no offset component, after the AB gain adjustment, an offset component is required due to the AB gain adjustment method. May be applied. In other words, if the point at AB = 0 is shifted from the lens center, the rotation center of the TE offset adjustment coincides with the point at AB = 0, and thus the point is shifted from the lens center position. Therefore, it is conceivable that an offset component is applied to the adjustment result when AB gain adjustment is performed by shifting the lens by a predetermined amount ± p lens as shown in FIG.

The present invention solves such a problem, and
It is an object of the present invention to provide an automatic optical disk adjustment apparatus that can accurately execute offset removal at a position where a lens shift is not performed before B gain adjustment.

[0018]

In order to solve the above-mentioned problem of removing the offset component, an automatic optical disk adjusting apparatus according to the present invention comprises a TE balance adjusting means and an AB gain adjusting means which will be described later in the section of the embodiment of the present invention. Means.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1, wherein a rotating means for rotating an optical disk on which information is recorded in a predetermined track shape, an objective lens for condensing a light beam on the optical disk, and the objective lens To form a light spot by reflecting from the optical disk, dividing the light spot substantially perpendicularly to a direction corresponding to a track, and dividing the light spot into an end area and a middle area with respect to the center thereof. A first dividing means, a second dividing means for further dividing the light spots in the end area and the middle area substantially parallel to a direction corresponding to the track, and a first dividing means. And a light receiving element having a plurality of light receiving cells for receiving the light in the area divided by the second dividing means, and before receiving the light in the end area divided by the second dividing means. Performs the operation of the outputs of the light-receiving cell,
A light spot shift signal detecting means for detecting a relative displacement of the light spot on the light receiving element, and an arithmetic operation between outputs of the light receiving cells for receiving the light in the middle area divided by the second dividing means. Tracking error detecting means for detecting a relative displacement between the track and the objective lens; multiplying means for multiplying an output signal of the light spot shift signal detecting means by a predetermined coefficient; and an output of the multiplying means and the tracking. A tracking balance having a function of performing a tracking adjustment process for adjusting the balance of the output signal of the offset correction unit, and an offset correction unit for correcting the offset of the tracking error signal by calculating the difference between the output signals of the error detection unit. A voltage is applied to an adjusting unit and an actuator of the objective lens, and the objective lens is moved to a predetermined position. An objective lens driving means for displacing,
An optical spot shift signal coefficient adjusting means including a lens shift adjusting process for adjusting the predetermined coefficient so as to remove an offset of the tracking error signal while the objective lens is displaced to a predetermined position; and the tracking balance adjustment. And a tracking control means forming a tracking control system for the tracking error signal corrected by the light spot deviation signal coefficient adjusting means, and removing the offset by combining the tracking balance means and the lens shift adjustment processing. It has the effect of doing.

According to a second aspect of the present invention, a lens shift adjustment process is performed after the tracking balance adjustment process is completed, and a tracking error offset in a state where no lens shift is performed using a tracking balance means is removed. This has the effect of starting the lens shift adjustment processing accurately from the position where the lens shift amount is 0.

According to a third aspect of the present invention, the tracking balance adjustment processing is performed after the lens shift adjustment processing is completed, and has an effect of removing an offset after performing the lens shift adjustment processing.

According to a fourth aspect of the present invention, a lens shift adjustment process is performed after the tracking balance adjustment process is completed, and a tracking balance adjustment process is further performed after the lens shift adjustment process is completed. The means has the effect of performing the lens shift adjustment processing both before and after the lens shift adjustment processing and removing the offset.

According to a fifth aspect of the present invention, a predetermined voltage is automatically applied to a tracking actuator, or a predetermined voltage is not automatically applied to a tracking actuator. When the processing using the coefficient adjusting means is completed, the output of the tracking balance deviation detecting means is automatically given as an input of the tracking control means, and the output voltage of the tracking control means is automatically applied to the actuator of the objective lens. It automatically performs a process of performing a lens shift adjustment process after performing a tracking balance adjustment process, and then performing a tracking balance adjustment process after the lens shift adjustment process is completed, using a switch. , And track according to each condition It has an effect of automatically switching with the switch the voltage applied to the grayed actuator.

(Embodiment 1) FIG. 1 is a block diagram of an optical disk apparatus according to Embodiment 1 of the present invention.
Reference numeral 6 denotes a tracking balance setting unit that sets a tracking balance of the TE1 signal output from the offset correction unit 15, 17 denotes a tracking balance deviation detecting unit that detects a deviation of the tracking balance from a reference voltage (Vref), and 18 denotes a tracking balance deviation. The value fed back to the setting means 16 is such that the tracking balance deviation is zero.
The tracking balance adjusting means 19, which adjusts and determines so that the voltage is not applied to the objective lens 4, is a voltage applying off means which does not apply a voltage to both ends of the tracking actuator 5; An objective lens driving means 21 for applying a voltage for displacing the objective lens 4 to a predetermined position; 21 adjusts a coefficient K by which A to B of the light receiving element 9 when the lens is shifted by the objective lens driving means 20; The coefficient adjusting means 22 is a TE balance / AB gain switch for automatically switching the signal flow to one of the tracking balance adjusting means 18, the coefficient adjusting means 21 or the tracking control means 6, and 23 is applied to the actuator. Voltage applying means 19 for applying voltage, objective lens driving means 20
Alternatively, it is a tracking actuator drive voltage changeover switch that automatically switches to one of the tracking control means 6. The same members as those in the prior art shown in FIG. 9 are denoted by the same reference numerals, and detailed description is omitted.

The optical disk automatic adjusting apparatus according to the first embodiment configured as described above will be described more specifically with reference to FIGS. 2, 3 and 4. FIG. 2 shows a case where the displacement of the objective lens 4 is shifted from the center of the optical axis of the light beam to a position of −250 μm inside the disk in the first embodiment.
FIG. 2B shows a case where the displacement of the objective lens 4 is shifted from the center of the optical axis of the light beam to a position of +250 μm outside the disk, as shown in FIG. 2C.

FIG. 5 shows a state in which a voltage is applied between the tracking actuators in order to displace the objective lens 4. The light spot 7 generated from the reflected light from the disk by the movement is the center of the light receiving element 9. FIG. That is, specifically, when no voltage is applied between the tracking actuators 5, the objective lens 4 is located at a position indicated by a solid line (FIG. 2A).
When the voltage is applied, the objective lens 4 moves to the position shown by the broken line (see FIGS. 2B and 2C).

FIG. 3 shows the DC component of the uncorrected TE (= CD) signal output by the TE detection means 13 in FIG. 1, that is, the offset component of the output signal of the TE detection means 13. Further, the output of the light spot displacement detecting means 12 is multiplied by the coefficient K of the amplifying means 14 to show a K (AB) signal which is a component for removing the offset of TE. At this time, the coefficient K is multiplied by AB so that the offset of the CD signal becomes zero.

FIG. 4 shows the offset correcting means 1 in FIG.
5 shows an output signal (TE1 signal). As shown in FIG.
By varying the coefficient K of the amplification means 14, the offset of the TE signal varies.

When the relative position between the light beam and the track changes, the zero-order light in the push-pull region 8 in FIG.
Since the manner of interference of the next light changes, the difference component (CD component of the light receiving cell 9) in the middle region changes in a sine wave shape as shown by a broken line in FIG. A TE signal containing a push-pull component is obtained. At this time, the sine wave rotates 360 degrees in phase by one track movement. Further, in the end region, since the interference between the 0th order light and the ± 1st order light does not occur, the difference component (AB component of the light receiving cell 9) of the end region does not generate a sine wave as shown in FIG.

When the displacement of the objective lens 4 coincides with the optical axis of the light beam, that is, when the lens shift amount is 0,
Since the light spot 7a is located at the center of the light receiving element 9 as shown in FIG. 2A, the dashed waveform in FIG. , The K (AB) signal which is a difference signal in the end region is almost 0.
Becomes

When the lens is shifted and the irradiation position of the light beam is shifted from the optical axis, the relative displacement between the light spot 7b and the light receiving element 9 is substantially perpendicular to the track as shown in FIGS. 2 (a) and 2 (b). Therefore, the difference signal in the middle area is a signal obtained by adding an offset corresponding to the lens shift amount to the TE signal as shown by a sine wave-shaped broken line in FIG. The difference signal in the end region can be considered as an offset removal signal corresponding to the displacement of the objective lens as indicated by K (AB). By changing the value of K as shown in FIG. 4, it is possible to generate a TE1 signal that has been subjected to AB gain adjustment so that the offset amount becomes zero.

By the way, as described in the section of the problem to be solved by the invention, the objective lens 4 is actually located at the position shown by the broken line in FIG. There is a case where the position of 4 is deviated from the optical axis center of the light beam. Therefore, in the first embodiment, in order to accurately perform the AB gain adjustment even when there is an offset component, a process of performing the tracking balance adjustment at a position where the lens is not shifted is performed.

First, the tracking actuator drive voltage changeover switch 23 is automatically switched to the voltage application off means 19, and the TE1 signal which is the output signal of the offset correction means 15 in the state where the AB gain adjustment is not performed is changed to the tracking balance setting means 16 Is input to the tracking balance deviation detecting means 17 via the interface, and the tracking balance deviation at this time is detected. Further, as shown in FIG. 6, the deviation amount of the amplitude of TE1 from the reference amplitude of 1.5 V is detected, and TE1 from the center of the reference voltage (Vref) is detected.
Of the amplitude center is detected.

Next, the TE balance / AB gain switch 22 is manually or automatically switched to the tracking balance adjusting means 18 and the output of the tracking balance deviation detecting means 17 is changed to the tracking balance adjusting means 1.
8 to determine the tracking balance adjustment value TB based on the center position of the objective lens 4. The determined value is input to the tracking balance setting means 16,
As shown in FIGS. 6 and 8, a TE2 signal (TE2 = CDK (AB) + T
B) can be generated. At this time, the rotation from the straight line a to the straight line b in FIG. 7 has been executed.

In the apparatus shown in FIG. 1, the offset is adjusted by taking the difference between TE1 and the tracking balance. However, the balance and gain of each signal before taking the difference of TE1 by the offset correction means 15 are adjusted. Needless to say, by changing the TE balance,
This configuration does not hinder the present invention.

Next, the tracking actuator drive voltage switch 23 shown in FIG.
Automatically, and a voltage is applied from the objective lens driving means 20 to the tracking actuator 5 so that the objective lens 4
Are shifted by a predetermined amount toward the inner and outer circumferences of the optical disk, and the coefficient K of the amplifying means 14 is varied as shown in FIG. 4 while being shifted from the center of the optical axis of the light beam.
Adjustment is made to remove the offset of TE1 which is B). Further, the TE1 signal is input to the tracking balance deviation detecting means 17, and the TE balance / AB gain changeover switch 22 is automatically switched to the coefficient adjusting means 21 to adjust the balance of the signal detected by the tracking balance deviation detecting means 17. Is sequentially adjusted.
Thus, the AB gain adjustment is performed. At this time, the rotation from the straight line b to the straight line c in FIG. 7 has been executed.

As described above, the TE balance adjustment and the AB gain adjustment are performed, and when these processes are completed, the TE balance / AB gain switch 22 is automatically switched to the tracking control means 6 and the tracking actuator drive voltage switch 23 is switched. By automatically switching to the tracking control means 6, a tracking error signal obtained by normalizing disturbances and deviations of the tracking error signal is input to the tracking control means 6, thereby forming a tracking control system.

(Embodiment 2) Embodiment 2 of the present invention
Is the TE gain after the AB gain adjustment described in the first embodiment.
The offset is removed by executing the balance adjustment. Note that AB gain adjustment and TE balance adjustment are the same as those in the first embodiment, and thus description thereof is omitted.

In FIG. 1, after the AB gain adjustment is performed, if the point of AB = 0 is shifted as shown by the straight line c in FIG. 7, the point of AB = 0 is the TE offset adjustment. Since it coincides with the center of rotation, AB in Embodiment 1
Offset adjustment is performed around the point of = 0. That is, when the AB gain is adjusted by shifting ± p (± 250 μm in the second embodiment), the rotation center (A
Since the adjustment is performed based on the offset voltage held at (−B = 0), the AB gain adjustment must be completed with the offset applied so as to move from the straight line b to the straight line c in FIG. Becomes Therefore, in the second embodiment, A
The tracking balance adjustment is performed on the TE1 signal which is the tracking error signal after the B gain adjustment.

First, after the AB gain is adjusted in the same manner as in the first embodiment, the tracking actuator drive voltage changeover switch 23 is automatically switched to the voltage application off means 19, and the TE1 signal after the AB gain adjustment is transferred to the tracking balance setting means. The signal is input to the tracking balance deviation detecting means 17 via the line 16 to detect the tracking balance deviation at this time. At this time, as shown in FIG. 6, the deviation of the amplitude of TE1 from the reference amplitude 1.5V is detected, and the deviation of the amplitude center of TE1 from the center of the reference voltage (Vref) is detected.

Next, the TE balance / AB gain changeover switch 22 is automatically switched to the tracking balance adjusting means 18, the output of the tracking balance deviation detecting means 17 is input to the tracking balance adjusting means 18, and the tracking balance adjustment value is set. decide. The determined value is input to the tracking balance setting means 16, and a TE2 signal in which the TE balance is normalized and adjusted as shown in FIGS. 6 and 8 can be generated. At this time, the movement from the straight line c to the straight line d in FIG. 7 has been executed.

As described above, the TE balance is adjusted from the AB gain adjustment, and when these processes are completed, the TE balance / AB gain switch 22 is automatically switched to the tracking control means 6 and the tracking actuator drive voltage switch 23 is switched. By automatically switching to the tracking control means 6, a tracking error signal obtained by normalizing disturbances and deviations of the tracking error signal is input to the tracking control means 6, thereby forming a tracking control system.

(Embodiment 3) Embodiment 3 of the present invention
In this embodiment, the AB gain adjustment and the TE balance adjustment described in the first and second embodiments are simultaneously performed. That is, a series of operations from a straight line a to a straight line b, a straight line b to a straight line c, and a straight line c to a straight line d in FIG. 7 are executed. The AB gain adjustment and the TE balance adjustment are the same as those in the first and second embodiments, and thus will not be described.

From the TE balance adjustment, through the AB gain adjustment, the TE balance adjustment is performed. When these processes are completed, the TE balance / AB gain switch 2
2 is automatically switched to the tracking control means 6 and the tracking actuator drive voltage changeover switch 23 is automatically switched to the tracking control means 6 to perform tracking control of the tracking error signal in which disturbance and deviation of the tracking error signal are normalized. Input to means 6,
Construct a tracking control system.

[0045]

As described above, according to the present invention, by combining the TE balance adjustment and the AB gain automatic adjustment, it is possible to perform the AB gain automatic adjustment in a state where the TE balance before the AB gain adjustment is shifted. Moreover, it is possible to eliminate the TE balance deviation after the automatic adjustment of the AB gain.

As a result, not only the TE balance at the lens center but also the TE balance can be minimized even when the lens is shifted, so that the tracking pull-in,
And the tracking access operation can be performed smoothly.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an optical disc automatic adjustment device according to a first embodiment of the present invention.

FIG. 2 is a table showing a relationship between a light receiving area and a light spot when the objective lens of FIG. 1 is displaced inward and outward, and a state of a change in light amount of each signal of the light receiving area when the objective lens is displaced. Illustration

FIG. 3 is an explanatory diagram showing an output of a TE detection unit and an output of an amplification unit in FIG. 1;

FIG. 4 is an explanatory view showing a state of offset removal by changing a coefficient K from an output of the TE detection means in FIG. 1 and subtracting an output of the amplification means.

FIG. 5 is an explanatory diagram showing that an objective lens is displaced by applying a voltage to the tracking actuator of FIG. 1;

FIG. 6 is an explanatory diagram showing a change in a tracking error signal after a series of operations of a tracking balance deviation detecting unit, a tracking balance adjusting unit, and a tracking balance setting unit of FIG. 1 are completed.

FIG. 7 shows tracking balance adjustment, AB gain adjustment,
Explanatory drawing showing a series of offset removal contents of tracking balance adjustment

FIG. 8 is an explanatory diagram of a light receiving area for generating a tracking error signal when tracking balance adjustment is incorporated.

FIG. 9 is a block diagram showing a configuration of a conventional optical disc automatic adjustment device.

[Explanation of symbols]

Reference Signs List 1 optical disk 2 turntable 3 motor 4 objective lens 5 tracking actuator 6 tracking control means 7 light spot 8 push-pull area 9 light receiving element 10, 11 dividing line 12 light spot displacement detecting means 13 tracking error detecting means 14 amplifying means 15 offset correcting means Reference Signs List 16 tracking balance setting means 17 tracking balance deviation detecting means 18 tracking balance adjusting means 19 voltage applying off means 20 objective lens driving means 21 coefficient adjusting means 22 TE balance / AB gain switching switch 23 tracking actuator driving voltage switching switch

Claims (5)

[Claims] A rotating means for rotating an optical disc on which information is recorded in a predetermined track shape; an objective lens for condensing a light beam on the optical disc; condensing light by the objective lens and reflecting off the optical disc; A first dividing means for forming a light spot with the light spot, dividing the light spot substantially perpendicular to a direction corresponding to a track, and forming the light spot into an end region and a middle region with respect to the center thereof; A second dividing unit that further divides the light spots in the end region and the middle region substantially parallel to a direction corresponding to the track, and is divided by the first dividing unit and the second dividing unit. A light receiving element having a plurality of light receiving cells for receiving light in the divided area, and an output of the light receiving cells for receiving light in the end area divided by the second dividing means. And a light spot shift signal detecting means for detecting a relative displacement of the light spot on the light receiving element, and outputs of the light receiving cells for receiving the light in the middle area divided by the second dividing means. A tracking error detecting means for detecting a relative displacement between the track and the objective lens; a multiplying means for multiplying an output signal of the light spot displacement signal detecting means by a predetermined coefficient; and an output of the multiplying means. Offset correction means for correcting the offset of the tracking error signal by calculating the difference between the output signal of the tracking error detection means and a function of performing tracking adjustment processing for adjusting the balance of the output signal of the offset correction means. Applying a voltage or the like to the tracking balance adjusting means and the actuator of the objective lens, Objective lens driving means for displacing the lens to a predetermined position; and lens shift adjustment processing for adjusting the predetermined coefficient so as to remove the offset of the tracking error signal while the objective lens is displaced to the predetermined position. An optical disc comprising: a light spot shift signal coefficient adjusting means; a tracking balance adjusting means; and a tracking control means forming a tracking control system for the tracking error signal corrected by the light spot shift signal coefficient adjusting means. Automatic adjustment device. 2. The optical disk automatic adjusting apparatus according to claim 1, wherein a lens shift adjusting process is performed after the tracking balance adjusting process is completed. 3. After ending the lens shift adjustment processing,
2. The optical disk automatic adjusting apparatus according to claim 1, wherein a tracking balance adjusting process is performed. 4. The automatic optical disc drive according to claim 1, wherein a lens shift adjustment process is performed after the tracking balance adjustment process is completed, and a tracking balance adjustment process is further performed after the lens shift adjustment process is completed. Adjustment device. 5. A method of automatically applying a predetermined voltage to a tracking actuator, or not applying a predetermined voltage automatically, or using a tracking balance adjusting means and a light spot shift coefficient adjusting means. The output of the tracking balance deviation detecting means is automatically given as an input to the tracking control means when the processing which has been completed is completed, and a means is provided for automatically applying the output voltage of the tracking control means to the actuator of the objective lens. 2. The automatic optical disk adjusting device according to claim 1, wherein: