JP3731445B2 - Disc player and initial adjustment method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disc reproducing apparatus and an adjustment method capable of appropriately adjusting the tilt angle of an objective lens optical axis and the position of a movement locus of the objective lens optical axis.
[0002]
[Prior art]
With the widespread use of music CDs (compact discs) and the like, disc playback devices represented by CD players have become one of the most popular music playback devices. In this disk reproducing apparatus, an optical pickup irradiates a generated laser beam on a recording surface of a disk via an objective lens, and condenses reflected light from the disk on a light detection element via the same objective lens. Reading the data recorded on the disc.
[0003]
Such a disc reproducing apparatus accurately irradiates a target track provided on the recording surface of the disc with a laser beam, and accurately condenses the reflected light from the disc at a predetermined position of the light detection element. The optical axis of the objective lens is adjusted in advance so as to be perpendicular to the recording surface of the disc.
In addition, a disk reproducing apparatus that performs tracking control by the three-spot method is adjusted in advance so that the movement locus (on the extension line) of the optical axis of the objective lens coincides with the position of the center of the disk. That is, when the preceding spot, the main spot, and the subsequent spot (three spots) are translated in the feed direction of the optical pickup, no deviation occurs between the spot pitch interval and the track pitch interval. The movement trajectory is adjusted to overlap the center of the turntable.
[0004]
Hereinafter, a conventional disk reproducing apparatus will be described with reference to FIG. FIG. 5 is a perspective view showing a configuration of an optical pickup or the like provided in a conventional disc reproducing apparatus.
The disc reproducing apparatus shown in FIG. 5 includes an optical pickup 101 provided with an objective lens 102, and a main guide shaft 103 and a sub guide shaft 104 that hold the optical pickup 101 movably in the radial direction of the disc (Y direction in the figure). And a bearing 105 fixed on a traverse chassis (not shown).
[0005]
In such a disk reproducing apparatus, since the main guide shaft 103 and the like are fixed to the traverse chassis via the bearing 105, the position of the optical axis L of the objective lens 102 and the disk mounted on the turntable (not shown). The relationship is determined by the dimensional accuracy of the component parts, the assembly accuracy, and the like.
Since the dimensional accuracy and the like of the component parts are naturally limited, such a disk reproducing apparatus is provided with a predetermined adjusting mechanism in the bearing 105. That is, the bearing 105 is provided with an adjusting mechanism including at least one set of spring member 111 and adjusting screw 112 as shown in FIG. 6A is a cross-sectional view of the bearing 105, and FIG. 6B is a perspective view of the bearing 105.
[0006]
The spring member 111 is embedded in the bearing 105, and biases the abutting main guide shaft 103 and the like with a predetermined elastic force.
The adjustment screw 112 is screwed into a position facing the spring member 111 with the main guide shaft 103 or the like interposed therebetween, and presses the main guide shaft 103 or the like.
[0007]
The positional relationship between the optical axis L of the objective lens 102 and the disk is adjusted by the adjusting mechanism provided in the bearing 105.
Specifically, the inclination angle of the main guide shaft 103 and the like is adjusted according to the degree of rotation of the adjustment screw 112, and the inclination angle and the like of the optical pickup 101 are adjusted accordingly. That is, the adjustment screw 112 is adjusted so that the optical axis L is perpendicular to the recording surface of the disk and the movement locus of the optical axis L overlaps the center of the turntable.
[0008]
[Problems to be solved by the invention]
However, the conventional disk reproducing apparatus as shown in FIG. 5 may not be able to properly adjust the inclination angle of the optical axis L and the position of the movement locus of the optical axis L.
This is affected by the further miniaturization of the disc to be played back. That is, in order to perform stable data reproduction from a disk that has been miniaturized, it is necessary to adjust the tilt angle with higher accuracy.
On the other hand, in the disc reproducing apparatus of FIG. 5, the adjustment screw 112 is adjusted by an operator or the like, but in this case, the inclination angle of the optical axis L may not be adjusted properly. .
[0009]
Even if it is adjusted once, there may be a deviation in the inclination angle of the optical axis L or the like due to the displacement of the characteristics received from the usage environment or the secular change. In this case, it is necessary to adjust the adjustment screw 112 again, which is very complicated.
[0010]
Furthermore, the disk reproducing apparatus for mechanically adjusting the main guide shaft 103 and the like as shown in FIG. 5 has a complicated mechanism in the first place, which is very disadvantageous for cost, quality, and downsizing of the apparatus (unit). There was a problem of becoming.
[0011]
The present invention has been made in view of the above circumstances, and provides a disc reproducing apparatus and an adjusting method capable of appropriately adjusting the inclination angle of the objective lens optical axis and the position of the movement locus of the objective lens optical axis. With the goal.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, a disc player according to the first aspect of the present invention provides:
A disk playback device that reads information recorded on a disk by an optical pickup supported movably by a guide shaft,
A first pressing member that is embedded in a bearing that supports the guide shaft and presses the contacting guide shaft toward the optical axis direction of the optical pickup in accordance with an applied drive voltage;
A second pressing member that is embedded in a bearing that supports the guide shaft and presses the contacting guide shaft in a direction orthogonal to the optical axis of the optical pickup in accordance with an applied drive voltage;
Skew adjustment control means for controlling the drive voltage applied to the first pressing member so that the optical axis of the optical pickup is perpendicular to the recording surface of the disc in accordance with the RF output supplied from the optical pickup;
In accordance with the E output indicating the reflected light of the preceding spot and the F output indicating the reflected light of the subsequent spot supplied from the optical pickup, the extension line of the movement locus of the optical axis of the optical pickup is overlapped with the center of the turntable. EF phase difference adjustment control means for controlling the drive voltage applied to the second pressing member;
Storage means for storing drive voltages applied to the first and second pressing members controlled by the skew adjustment control means and the EF phase difference adjustment control means in a nonvolatile manner as skew adjustment values and EF adjustment values;
It is characterized by providing.
[0014]
The skew adjustment control means controls a drive voltage applied to the first pressing member so that fluctuation of the RF output supplied from the optical pickup is minimized,
The EF phase difference adjustment control unit may control a driving voltage applied to the second pressing member so that a phase difference between the E output and the F output approaches 180 degrees.
[0016]
In order to achieve the above object, a disc player according to the second aspect of the present invention provides:
A disk reproducing device for reading information recorded on a disk by an optical pickup supported movably by a main guide shaft and a sub guide shaft,
A first piezoelectric element that is embedded in a bearing that supports the main guide shaft and presses the main guide shaft that abuts in the direction of the optical axis of the optical pickup in accordance with an applied drive voltage;
Third and fourth piezoelectric elements embedded in a bearing supporting the sub guide shaft and pressing the sub guide shaft in contact with the applied drive voltage in the direction of the optical axis of the optical pickup;
Drive voltage applied to the first piezoelectric element and the third and fourth piezoelectric elements so that the optical axis of the optical pickup is perpendicular to the recording surface of the disk in accordance with the RF output supplied from the optical pickup. Skew adjustment control means for controlling
Embedded in a bearing that supports the main guide shaft, and in accordance with an applied drive voltage, the second and fifth piezoelectric elements that press the contacting main guide shaft in a direction perpendicular to the optical axis of the optical pickup;
According to the E output indicating the reflected light of the preceding spot and the F output indicating the reflected light of the subsequent spot supplied from the optical pickup, the extension line of the movement path of the optical axis of the optical pickup is overlapped with the center of the turntable. EF phase difference adjustment control means for controlling a drive voltage applied to the second and fifth piezoelectric elements;
A drive voltage applied to the first, third, and fifth piezoelectric elements and the second and fifth piezoelectric elements controlled by the skew adjustment control means and the EF phase difference adjustment control means is a skew adjustment value and Storage means for storing in a nonvolatile manner as an EF adjustment value;
It is characterized by providing.
[0018]
In order to achieve the above object, an initial adjustment method according to a third aspect of the present invention includes:
Skew adjustment of the optical pickup that is movably supported by the guide shaft, and have rows EF phase difference adjustment, a initial adjustment method for storing in a predetermined nonvolatile memory,
An RF output acquisition step of acquiring, as an RF output, a signal component of reflected light from a disk incident on a predetermined photodetector;
According to the RF output acquired in the RF output acquisition step, the guide shaft that comes into contact with the first piezoelectric element embedded in the bearing that supports the guide shaft is pressed toward the optical axis direction of the optical pickup. A skew adjustment control step for controlling the drive voltage to be applied;
An E output acquisition step of acquiring reflected light of a preceding spot incident on a predetermined light detection element as an E output;
An F output acquisition step of acquiring reflected light of a subsequent spot incident on a predetermined light detection element as an F output;
In accordance with the E output and F output acquired in the E output acquisition step and the F output acquisition step, the guide shaft that comes into contact with the second piezoelectric element embedded in the bearing that supports the guide shaft is used as the light of the optical pickup. An EF phase difference adjustment control step for controlling a drive voltage applied to press in a direction orthogonal to the axis, and
In the skew adjustment control step, the drive voltage applied to the first piezoelectric element is controlled so that the optical axis of the optical pickup is perpendicular to the recording surface of the disk, and applied to the controlled first piezoelectric element. A drive voltage to be stored as a skew adjustment value in the nonvolatile memory,
In the EF phase difference adjustment control step, the driving voltage applied to the second piezoelectric element is controlled so that the extension line of the movement locus of the optical axis of the pickup overlaps the center of the turntable, and the second piezoelectric element controlled is controlled. A drive voltage applied to the element is stored in the nonvolatile memory as an EF adjustment value .
It is characterized by that.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
A disk playback apparatus according to an embodiment of the present invention will be described below with reference to the drawings.
[0021]
FIG. 1A is a plan view showing an example of an optical pickup or the like provided in a disk reproducing device applied to the embodiment of the present invention. FIG. 1B is a side view thereof.
As shown in FIG. 1, the disk reproducing apparatus includes an optical pickup 1, an objective lens 2, a main guide shaft 3, a sub guide shaft 4, bearings 5a to 5d, a turntable 6, a clamper 7, and a spindle. A disk 9 including a motor 8 and made of a CD (compact disk) or the like mounted on the turntable 6 is reproduced.
[0022]
The optical pickup 1 is moved in the radial direction of the disk (Y direction in the figure) by the main guide shaft 3 and the sub guide shaft 4 so that data can be appropriately read from the disk 9 mounted on the turntable 6. It is supported freely.
[0023]
The objective lens 2 is embedded in the surface portion of the optical pickup 1 and irradiates a laser beam generated by a laser diode or the like toward the recording surface of the disk 9. Further, the reflected light from the disk is collected on a photodiode to be described later.
[0024]
The main guide shaft 3 is supported by a bearing 5a and a bearing 5b. The sub guide shaft 4 is supported by a bearing 5c and a bearing 5d.
The main guide shaft 3 and the like support the optical pickup 1 so as to be movable in the radial direction of the disk.
[0025]
The bearings 5 a to 5 d are fixed on a traverse chassis (not shown) and support the main guide shaft 3 and the sub guide shaft 4. Specifically, the bearings 5 a and 5 b support the main guide shaft 3, and the bearings 5 c and 5 d support the sub guide shaft 4. Hereinafter, the bearings 5a to 5d will be described with reference to the cross-sectional view of FIG.
[0026]
As shown in FIG. 2A, the bearing 5 a includes piezoelectric elements 11 a and 11 e and a spring member 12.
The piezoelectric elements 11 a and 11 e are embedded at predetermined positions inside the bearing 5 a and abut against the main guide shaft 3. The piezoelectric elements 11a and 11e are controlled in driving voltage or the like by a microcomputer to be described later, generate a predetermined distortion in accordance with the applied driving voltage or the like, and press the main guide shaft 3 in contact therewith.
[0027]
Specifically, as shown in FIG. 2A, the piezoelectric element 11a abuts on the main guide shaft 3 in the Z-axis direction (perpendicular to the turntable 6) and follows the applied drive voltage. 3 is pressed in the Z-axis direction.
2A, the piezoelectric element 11e contacts the main guide shaft 3 in the X-axis direction (the horizontal direction with respect to the turntable 6), and causes the main guide shaft 3 to move according to the applied drive voltage. Press in the X-axis direction.
[0028]
The spring members 12 are respectively embedded in positions facing the piezoelectric elements 11a and 11e across the main guide shaft 3, and urge the main guide shaft 3 with a predetermined elastic force. The spring member 12 suppresses rattling of the main guide shaft 3 by urging the main guide shaft 3 pressed by the piezoelectric elements 11a and 11e from the opposite direction.
[0029]
As shown in FIG. 2B, the bearing 5b includes a piezoelectric element 11b and a spring member 12 embedded in a predetermined position.
As illustrated, the piezoelectric element 11b abuts on the main guide shaft 3 in the X-axis direction (horizontal direction with respect to the turntable 6), and presses the main guide shaft 3 in the X-axis direction according to the applied drive voltage.
The spring member 12 suppresses rattling of the main guide shaft 3.
[0030]
The bearing 5c includes a piezoelectric element 11c and a spring member 12 as shown in FIG. 2 (c), and the bearing 5d includes a piezoelectric element 11d and a spring member 12 as shown in FIG. 2 (d). Yes.
The piezoelectric elements 11c and 11d are in contact with the sub guide shaft 4 in the Z-axis direction (perpendicular to the turntable 6) and press the sub guide shaft 4 in the Z-axis direction according to the applied drive voltage, as shown in the figure. To do.
The spring member 12 suppresses rattling of the sub guide shaft 4.
[0031]
The inclination angles of the main guide shaft 3 and the sub guide shaft 4 are adjusted by the piezoelectric elements 11a to 11e embedded in the bearings 5a to 5d. Accordingly, the inclination angle of the optical pickup 1 is adjusted accordingly.
[0032]
Returning to FIG. 1, the turntable 6 is pivotally supported by the spindle motor 8 and is driven to rotate as the spindle motor 8 rotates with the disk 9 mounted.
[0033]
The clamper 7 presses the disk 9 mounted on the turntable 6 with a predetermined urging force so that the disk 9 is brought into close contact with the turntable 6.
[0034]
The spindle motor 8 supports the turntable 6. Then, it is controlled by a predetermined spindle servo circuit, and the turntable 6 on which the disk 9 is mounted is driven to rotate so that the angular velocity or linear velocity is constant.
[0035]
Hereinafter, a circuit configuration for controlling the piezoelectric elements 11a to 11e and the like in the disk reproducing apparatus described above will be described with reference to FIG. FIG. 3 is a block diagram showing an example of a control circuit in a disc reproducing apparatus employing a three-spot method (preceding spot, main spot, and trailing spot).
[0036]
As shown in the figure, the disk reproducing apparatus includes a pickup 1, an objective lens 2, a coil 21, a magnet 22, photodiodes 23 to 25, piezoelectric elements 11a to 11e, and a microcomputer 31. The
[0037]
For example, the coil 21 is wound around a bobbin on which the objective lens 2 is mounted, and moves the objective lens 2 in the focus direction or the like according to a drive voltage or the like controlled by the microcomputer 31.
[0038]
The magnet 22 is disposed at a position facing the coil 21, and moves the objective lens 2 according to a current flowing through the coil 21.
[0039]
The photodiode 23 is divided into four sections and receives the reflected light of the main spot collected by the objective lens 2. The photodiode 23 supplies the microcomputer 31 with outputs (A to D outputs) corresponding to the amount of light incident on each section.
[0040]
The photodiode 24 receives the reflected light of the preceding spot collected by the objective lens 2. The photodiode 24 supplies an output (E output) corresponding to the amount of incident light to the microcomputer 31.
[0041]
The photodiode 25 receives the reflected light of the subsequent spot collected by the objective lens 2. The photodiode 25 supplies the microcomputer 31 with an output (F output) corresponding to the amount of incident light.
[0042]
The microcomputer 31 includes, for example, an EPROM (Erasable and Programmable Read Only Memory), a RAM (Random Access Memory), a CPU (Central Processing Unit), a driver circuit, and the like, and applies them to the coil 21 and the piezoelectric elements 11a to 11e. Control drive voltage and so on.
That is, the microcomputer 31 monitors the focal position of the main spot on the recording surface of the disk 9 in accordance with the A to D outputs sent from the photodiode 23, and controls the drive voltage applied to the coil 21, etc. The focus of the lens 2 is adjusted.
[0043]
Specifically, the microcomputer 31 controls the drive voltage and the like applied to the coil 21 so that the A to D outputs satisfy Formula 1.
[0044]
[Expression 1]
(A + B)-(C + D) ≈0
A to D: Outputs from the photodiode 23
Further, the microcomputer 31 monitors the inclination of the optical axis of the objective lens 2 in accordance with the RF signal (I pattern) sent from the optical pickup 1 and controls the drive voltage applied to the piezoelectric elements 11a, 11c, and 11d. Thus, the skew (radial skew and tangential skew) is adjusted so that the optical axis of the objective lens 2 is perpendicular to the recording surface of the disk 9.
[0046]
Specifically, the microcomputer 31 controls the drive voltage applied to the piezoelectric elements 11a, 11c, and 11d so that the fluctuation of the I pattern (the amount of displacement in the time axis direction) is minimized.
[0047]
Further, the microcomputer 31 monitors the position of the optical pickup 1 in the track direction (positional relationship between the three spots and the track) in accordance with the E output and F output sent from the photodiodes 24 and 25, and applies the piezoelectric elements 11b and 11e to the piezoelectric elements 11b and 11e. By controlling the applied drive voltage or the like, the EF phase difference is adjusted so that the movement locus of the optical axis of the objective lens 2 overlaps the center of the turntable.
[0048]
Specifically, the microcomputer 31 controls the drive voltage applied to the piezoelectric elements 11b and 11e so that the phase difference between the E output and the F output is approximately 180 degrees.
[0049]
The operation of the disc reproducing apparatus according to the embodiment of the present invention will be described below with reference to FIG.
FIG. 4 is a flowchart for explaining the initial adjustment process performed by the microcomputer 31. The adjustment process shown in FIG. 4 is started, for example, when a predetermined reset signal for instructing the initial adjustment is supplied to the disk reproducing apparatus.
[0050]
First, the microcomputer 31 drives the objective lens 2 in the focus direction and monitors the output from the photodiode 23 (step S11). That is, the microcomputer 31 samples the A to D outputs.
The microcomputer 31 adjusts the drive voltage applied to the coil 21 (step S12).
The microcomputer 31 determines whether or not the sampled A to D outputs satisfy the condition of Equation 1 described above (step S13).
[0051]
If the microcomputer 31 determines that the A to D outputs do not satisfy the condition of Equation 1, the microcomputer 31 returns the process to step S11 and repeats the processes of steps S11 to S13 described above.
On the other hand, when it is determined that the A to D outputs satisfy the condition of Expression 1, the microcomputer 31 stores the focus adjustment value (step S14). That is, the current drive voltage applied to the coil 21 is stored in the EPROM as a focus adjustment value.
[0052]
Next, the microcomputer 31 monitors the RF output (I pattern) from the optical pickup 1 (step S15).
The microcomputer 31 adjusts the drive voltage applied to the piezoelectric elements 11a, 11c, and 11d (step S16).
The microcomputer 31 determines whether or not the fluctuation of the I pattern is minimum (step S17). That is, the microcomputer 31 determines whether or not the displacement amount of the I pattern in the time axis direction is the minimum.
[0053]
If the microcomputer 31 determines that the fluctuation of the I pattern is not minimum, the microcomputer 31 returns the process to step S15 and repeats the processes of steps S15 to S17 described above.
On the other hand, when it is determined that the fluctuation of the I pattern is the minimum, the microcomputer 31 stores the skew adjustment value (step S18). That is, the microcomputer 31 stores the current drive voltage applied to the piezoelectric elements 11a, 11c, and 11d as a skew adjustment value in the EPROM.
[0054]
Next, the microcomputer 31 monitors the outputs from the photodiodes 24 and 25 (step S19). That is, the microcomputer 31 monitors the phase difference between the E output and the F output.
The microcomputer 31 adjusts the drive voltage applied to the piezoelectric elements 11b and 11e (step S20).
The microcomputer 31 determines whether or not the phase difference between the E output and the F output is approximately 180 degrees (step S21).
[0055]
When the microcomputer 31 determines that the phase difference between the E output and the F output is not 180 degrees, the microcomputer 31 returns the process to step S19 and repeats the processes of steps S19 to S21 described above.
On the other hand, when it is determined that the phase difference between the E output and the F output is approximately 180 degrees, the microcomputer 31 stores the EF adjustment value (step S22). That is, the microcomputer 31, the piezoelectric element 11b, and the current drive voltage applied to 11e as EF adjustment value stored in the E PROM.
[0056]
Using the skew adjustment value and the EF adjustment value obtained by such initial adjustment processing, the microcomputer 31 controls the drive voltage applied to the piezoelectric elements 11a to 11e at the normal time.
Therefore, a drive voltage is applied to the piezoelectric elements 11a, 11c, and 11d so that the optical axis of the objective lens 2 is perpendicular to the recording surface of the disk 9, and the extension line on the movement locus of the optical axis is on the turntable. A driving voltage is applied to the piezoelectric elements 11b and 11e so as to overlap with the center of the piezoelectric element 11b.
As a result, the inclination angle of the objective lens optical axis and the position of the movement locus of the objective lens optical axis can be appropriately adjusted.
[0057]
In addition, since the main guide shaft 3 and the like are not mechanically adjusted, it is possible to prevent the reproduction performance of the optical disk from being deteriorated due to variations in component parts and variations in assembly thereof.
Further, since the main guide shaft 3 and the like are not mechanically adjusted, it is possible to suppress the displacement of the characteristics and the secular change that are received from the use environment, and to prevent the reproduction performance of the optical disc from being deteriorated.
Furthermore, even when the displacement of the characteristic received from a use environment and the secular change have arisen, it can readjust accurately in a short time.
[0058]
In the above-described embodiment, two piezoelectric elements 11a and 11e are disposed on the bearing 5a, one piezoelectric element 11b is disposed on the bearing 5b, and one piezoelectric element 11c and 11d is disposed on each of the bearing 5c and the bearing 5d. However, the number and arrangement direction of the piezoelectric elements (direction in which the main guide shaft 3 and the like are pressed) are arbitrary.
For example, either the skew or the EF phase difference may be adjusted by reducing the number of arranged piezoelectric elements. In addition, when the skew adjustment and the EF phase difference adjustment do not require so high accuracy, the number of piezoelectric elements arranged may be reduced.
[0059]
In the above-described embodiment, the inclination angles and the like of the main guide shaft 3 and the sub guide shaft 4 are adjusted using the piezoelectric elements 11a to 11e. However, the volume, hardness, etc. are electrically replaced with the piezoelectric elements 11a to 11e. The same effect as described above can be obtained even by using an element having a characteristic of displacing.
Furthermore, the skew adjustment and the EF phase difference adjustment were performed by adjusting the inclination angles and the like of the main guide shaft 3 and the sub guide shaft 4 using the piezoelectric elements 11a to 11e. By adjusting, the skew and the EF phase difference may be adjusted.
[0060]
Further, in the above embodiment, a disc playback device for playing a CD has been described. However, a playback target medium is not limited to a CD, and other media such as an MD (mini disc) and a DVD (digital video disc) are played back. It can be applied to a disc playback apparatus.
[0061]
【The invention's effect】
As described above, according to the present invention, the inclination angle of the objective lens optical axis and the position of the movement locus of the objective lens optical axis can be appropriately adjusted.
[Brief description of the drawings]
FIGS. 1A and 1B are diagrams showing an example of a disk reproducing apparatus (main part) according to an embodiment of the present invention, where FIG. 1A is a plan view and FIG. 1B is a side view;
FIGS. 2A, 2B, 2C, and 2D are cross-sectional views for explaining the internal structure of the bearing.
FIG. 3 is a circuit block diagram showing an example of a disc playback apparatus (main part) according to an embodiment of the present invention.
FIG. 4 is a flowchart for explaining initial adjustment processing according to the embodiment of the present invention;
FIG. 5 is a perspective view showing an example of a conventional disk reproducing device (main part).
6A and 6B are diagrams for explaining an adjustment mechanism in a conventional disk reproducing device, in which FIG. 6A is a cross-sectional view, and FIG. 6B is a perspective view.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Optical pick-up 2 Objective lens 3 Main guide shaft 4 Sub guide shaft 5a-5d Bearing 6 Turntable 7 Clamper 8 Spindle motor 9 Disk 11a-11e Piezoelectric element 12 Spring member 21 Coil 22 Magnets 23-25 Photodiode 31 Microcomputer

Claims (4)

A disk playback device that reads information recorded on a disk by an optical pickup supported movably by a guide shaft,
A first pressing member that is embedded in a bearing that supports the guide shaft and presses the contacting guide shaft toward the optical axis direction of the optical pickup in accordance with an applied drive voltage;
A second pressing member that is embedded in a bearing that supports the guide shaft and presses the contacting guide shaft in a direction orthogonal to the optical axis of the optical pickup in accordance with an applied drive voltage;
Skew adjustment control means for controlling the drive voltage applied to the first pressing member so that the optical axis of the optical pickup is perpendicular to the recording surface of the disc in accordance with the RF output supplied from the optical pickup;
According to the E output indicating the reflected light of the preceding spot supplied from the optical pickup and the F output indicating the reflected light of the subsequent spot, the extension line of the movement locus of the optical axis of the optical pickup is overlapped with the center of the turntable. EF phase difference adjustment control means for controlling the drive voltage applied to the second pressing member;
Storage means for storing drive voltages applied to the first and second pressing members controlled by the skew adjustment control means and the EF phase difference adjustment control means in a nonvolatile manner as skew adjustment values and EF adjustment values;
A disc playback apparatus comprising: The skew adjustment control means controls a drive voltage applied to the first pressing member so that fluctuation of the RF output supplied from the optical pickup is minimized,
The EF phase difference adjustment control unit controls a driving voltage applied to the second pressing member so that a phase difference between the E output and the F output approaches 180 degrees.
The disc reproducing apparatus according to claim 1, wherein: A disk reproducing device for reading information recorded on a disk by an optical pickup supported movably by a main guide shaft and a sub guide shaft,
A first piezoelectric element that is embedded in a bearing that supports the main guide shaft and presses the main guide shaft that abuts in the direction of the optical axis of the optical pickup in accordance with an applied drive voltage;
Third and fourth piezoelectric elements embedded in a bearing supporting the sub guide shaft and pressing the sub guide shaft in contact with the applied drive voltage in the direction of the optical axis of the optical pickup;
Drive voltage applied to the first piezoelectric element and the third and fourth piezoelectric elements so that the optical axis of the optical pickup is perpendicular to the recording surface of the disk in accordance with the RF output supplied from the optical pickup. Skew adjustment control means for controlling
Second and fifth piezoelectric elements embedded in a bearing that supports the main guide shaft and pressing the main guide shaft that abuts in a direction orthogonal to the optical axis of the optical pickup according to an applied drive voltage;
According to the E output indicating the reflected light of the preceding spot and the F output indicating the reflected light of the subsequent spot supplied from the optical pickup, the extension line of the movement path of the optical axis of the optical pickup is overlapped with the center of the turntable. EF phase difference adjustment control means for controlling the drive voltage applied to the second and fifth piezoelectric elements;
A drive voltage applied to the first, third, and fifth piezoelectric elements and the second and fifth piezoelectric elements controlled by the skew adjustment control means and the EF phase difference adjustment control means is a skew adjustment value and Storage means for storing in a nonvolatile manner as an EF adjustment value;
A disc playback apparatus comprising: Skew adjustment of the optical pickup that is movably supported by the guide shaft, and have rows EF phase difference adjustment, a initial adjustment method for storing in a predetermined nonvolatile memory,
An RF output acquisition step for acquiring, as an RF output, a signal component of reflected light from a disk incident on a predetermined photodetector;
In accordance with the RF output acquired in the RF output acquisition step, the guide shaft that comes into contact with the first piezoelectric element embedded in the bearing that supports the guide shaft is pressed toward the optical axis direction of the optical pickup. A skew adjustment control step for controlling the drive voltage to be applied;
An E output acquisition step of acquiring reflected light of a preceding spot incident on a predetermined light detection element as an E output;
An F output acquisition step of acquiring reflected light of a subsequent spot incident on a predetermined light detection element as an F output;
In accordance with the E output and F output acquired in the E output acquisition step and the F output acquisition step, the guide shaft that comes into contact with the second piezoelectric element embedded in the bearing that supports the guide shaft is used as the light of the optical pickup. An EF phase difference adjustment control step for controlling a drive voltage applied for pressing in a direction perpendicular to the axis,
In the skew adjustment control step, the drive voltage applied to the first piezoelectric element is controlled so that the optical axis of the optical pickup is perpendicular to the recording surface of the disk, and applied to the controlled first piezoelectric element. A drive voltage to be stored as a skew adjustment value in the nonvolatile memory,
In the EF phase difference adjustment control step, the driving voltage applied to the second piezoelectric element is controlled so that the extension line of the movement locus of the optical axis of the pickup overlaps the center of the turntable, and the second piezoelectric element controlled is controlled. A drive voltage applied to the element is stored in the nonvolatile memory as an EF adjustment value .
An initial adjustment method characterized by that.

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