JP2005158137A - Tilt control method of optical disk recording or reproducing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tilt control method of an optical disk recording or reproducing apparatus which can record a signal on a disk with an optical pickup. <P>SOLUTION: While changing a level of a drive signal for offset sensing to be supplied to a coil for conditioning a tilt in a test writing area set up in inner periphery and periphery sides of a disk, the optical disk recording or reproducing apparatus performs reproducing operation of a signal for offset conditioning recorded after the signal for offset conditioning; detects a peak level of an RF signal to be reproduced; sets the level of the drive signals supplied to the coil for tilt conditioning as an inner periphery side offset value and a periphery side offset value, when the signals with which the peak level detected serves as the maximum are recorded; and performs tilt control by adding offset values according to record positions calculated from the inner periphery side offset value and the periphery side offset value to a tilt conditioning signal which performs tilt control. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a tilt control method for an optical disc recording / reproducing apparatus configured to record a signal on a disc by a laser beam irradiated from an optical pickup and perform a reproducing operation of the signal recorded on the disc by the laser beam. .

  Disc players that use an optical pickup to read signals recorded on a disc are widely used. In addition to the playback function, a signal can be recorded on the disc by a laser beam emitted from the optical pickup. An optical disc recording / reproducing apparatus configured so as to be able to be made has been commercialized.

  In the optical disc recording / reproducing apparatus, since it is necessary to accurately irradiate the signal track of the disc with the laser beam emitted from the optical pickup, the focus control operation and the tracking control operation are performed. Such a focus control operation is performed by supplying a drive current to a focusing coil that displaces the objective lens in the disk surface direction, and a tracking control operation is performed by applying a drive current to the tracking coil that displaces the objective lens in the radial direction of the disk. This is done by supplying.

  Recently, the recording density has been increased in order to record many signals on the disk. In order to perform a high-density recording operation, it is necessary to irradiate the disk surface with laser light in an optimum state. In order to perform such an operation, not only the above-described focus control operation and tracking control operation are accurately performed, but also an operation for correcting a relative angular deviation between the disc and the objective lens, that is, a tilt control operation is performed. An optical pickup configured to be able to be developed has been developed (for example, see Patent Document 1).

A technique for detecting the inclination of the optical pickup with respect to the disk and adjusting the inclination has been developed (see, for example, Patent Document 2).
JP 2002-197698 A JP 2001-52362 A

  The technology described in Patent Document 2 is configured to provide a tilt sensor that detects the tilt of the optical pickup with respect to the disk, and to perform a tilt adjustment operation based on a signal obtained from the tilt sensor. According to such a technique, although an accurate tilt adjustment control operation can be performed, the tilt sensor is expensive, and there is a problem that the optical disc recording / reproducing apparatus is expensive.

  In addition, the tilt adjustment coil incorporated in the optical pickup is fixed to a support member that supports the objective lens. Since there is a change over time, the tilt angle is not constant when the drive voltage is not supplied to the tilt adjustment coil. Therefore, there is a problem that accurate tilt adjustment is not performed when the tilt adjustment operation is performed in such a state.

The present invention is intended to provide a tilt control method for an optical disc recording / reproducing apparatus capable of solving such a problem.

  According to the first aspect of the present invention, after the offset adjustment signal is recorded while changing the level of the drive signal for offset detection supplied to the tilt adjustment coil in the test writing area provided on the inner peripheral side of the disc. The drive supplied to the tilt adjustment coil when the recorded offset adjustment signal is reproduced, the peak level of the reproduced RF signal is detected, and the signal with the maximum detected peak level is recorded The signal level is set as the inner circumference offset value, and the offset adjustment signal is changed while changing the level of the drive signal for offset detection supplied to the tilt adjustment coil at the outer circumference position of the signal recording area provided on the disc. After recording, the recorded offset adjustment signal is reproduced, the peak level of the reproduced RF signal is detected, and the detection is performed. The level of the drive signal supplied to the coil for tilt adjustment when the signal with the maximum peak level is recorded is set as the outer peripheral side offset value, and the inner peripheral side offset value and the tilt adjustment signal for tilt control are set. Tilt control is performed by adding an offset value corresponding to the recording position calculated from the outer peripheral offset value.

  According to the second aspect of the present invention, after the offset adjustment signal is recorded while changing the level of the drive signal for offset detection supplied to the tilt adjustment coil in the test writing area provided on the inner circumference side of the disc. Drive that is supplied to the tilt adjustment coil when the recorded offset adjustment signal is reproduced, the bottom level of the reproduced RF signal is detected, and the signal that minimizes the detected bottom level is recorded The signal level is set as the inner circumference offset value, and the offset adjustment signal is changed while changing the level of the drive signal for offset detection supplied to the tilt adjustment coil at the outer circumference position of the signal recording area provided on the disc. After recording, the recorded offset adjustment signal is reproduced, and the bottom level of the reproduced RF signal is detected. The level of the drive signal supplied to the coil for tilt adjustment when the signal with the lowest bottom level is recorded is set as the outer periphery side offset value, and the inner periphery side offset value and the tilt adjustment signal for performing tilt control are set. Tilt control is performed by adding an offset value corresponding to the recording position calculated from the outer peripheral offset value.

  According to the third aspect of the present invention, after the offset adjustment signal is recorded while changing the level of the drive signal for offset detection supplied to the tilt adjustment coil in the test writing area provided on the inner peripheral side of the disc. When the recorded offset adjustment signal is reproduced, the peak level and the bottom level of the reproduced RF signal are detected, and the signal that maximizes the difference between the detected peak level and the bottom level is recorded. The level of the drive signal supplied to the tilt adjustment coil is set as the inner peripheral offset value, and the offset detection drive signal supplied to the tilt adjustment coil at the outer peripheral position of the signal recording area provided on the disc is set. After the offset adjustment signal is recorded while the level is changed, the recorded offset adjustment signal is reproduced and reproduced. The peak level and bottom level of the signal are detected, and the level of the drive signal supplied to the tilt adjustment coil when the signal that maximizes the difference between the detected peak level and bottom level is recorded is set to the offset value on the outer circumference side. The tilt control is performed by adding an offset value corresponding to a recording position calculated from the inner peripheral offset value and the outer peripheral offset value to a tilt adjustment signal for performing tilt control.

The present invention records the offset adjustment after recording the offset adjustment signal while changing the level of the drive signal for offset detection supplied to the tilt adjustment coil in the test writing area provided on the inner circumference side of the disc. Signal is reproduced, the peak level or bottom level of the reproduced RF signal is detected, the signal having the maximum detected peak level, the signal having the lowest bottom level, or the peak level and the bottom level Set the level of the drive signal supplied to the tilt adjustment coil when the signal with the largest difference is recorded as the inner peripheral offset value, and further adjust the tilt to the outer peripheral position of the signal recording area provided on the disc. Record the offset adjustment signal after recording the offset adjustment signal while changing the level of the offset detection drive signal supplied to the coil. Performs the set adjustment signal playback operation, detects the peak level or bottom level of the RF signal to be played back, detects the signal with the highest peak level, the signal with the lowest bottom level, or the peak level and the bottom level The level of the drive signal supplied to the tilt adjustment coil when a signal with the largest difference is recorded is set as the outer peripheral offset value, and the inner peripheral offset value and the outer peripheral side are set in the tilt signal for tilt control. Since the tilt control is performed by adding an offset value corresponding to the recording position calculated from the offset value, it is accurate without being affected by the displacement of the mounting position of the tilt adjustment coil, the temperature change, and the change over time. Tilt adjustment can be performed.

  In particular, according to the present invention, offset adjustment is performed by calculating and setting an offset value corresponding to the recording position using the offset values set on the inner and outer peripheral sides of the disc. The tilt adjustment operation can be performed accurately.

  In the present invention, in the case of a disc in which a trial writing area is provided at the outer peripheral position, the setting operation of the outer peripheral offset value is performed using the trial writing area. This has the advantage of not affecting the signal recording operation.

  In the case of a disc in which no trial writing area is provided at the outer peripheral position, the present invention performs the setting operation of the outer peripheral offset value by using the spare area provided outside the signal recording area. Therefore, there is an advantage that there is no influence on the signal recording operation in the signal recording area.

  The present invention records the offset adjustment signal in the test writing area provided on the inner peripheral side of the disc and the outer peripheral side of the disc while changing the angle of the optical pickup with respect to the disc, thereby offset values at each position. Is to be selected.

  FIG. 1 is a circuit diagram showing an embodiment of an optical disc recording / reproducing apparatus according to the present invention, FIG. 2 is a signal waveform diagram for explaining the operation of the present invention, and FIG. 3 is a plan view showing a disc according to the present invention. .

  In FIG. 1, reference numeral 1 denotes a disk placed on a turntable (not shown) that is rotationally driven by a spindle motor (not shown). When the laser output is adjusted from the inner periphery as shown in FIG. Are provided with an inner circumference side trial writing area A, a PMA area B indicating the recorded contents of the disc, a signal recording area C, and an outer circumference side trial writing area D. The inner circumference side trial writing area A and the outer circumference side trial writing area D are areas used when the recording laser output is adjusted before performing the recording operation of the data signal in the signal recording area C. Since the method of adjusting the laser output using is well known, its description is omitted.

Further, position information data indicating the position on the disk is recorded on the disk 1 by meandering grooves called pregrooves, and the optical disk recording / reproducing apparatus records signals on the basis of wobble signals obtained from the grooves. A reproduction operation is performed. Reference numeral 2 denotes a laser diode 3 that emits laser light emitted to the disk 1 and a monitor diode (not shown) that monitors the amount of laser light emitted from the laser diode 3. An optical pickup incorporating a photodetector 4 that receives laser light reflected from the signal surface, and is configured to be moved in the radial direction of the disk 1 by a pickup feed motor (not shown). .

  Further, in the optical pickup 2, a focusing coil 5 for displacing an objective lens (not shown) in the surface direction of the disc 1, a tracking coil 6 for displacing the objective lens in the radial direction of the disc 1, and a disc of the objective lens. A tilt adjusting coil 7 for adjusting an angle with respect to 1 is incorporated.

  Reference numeral 8 denotes a focusing control operation for focusing the laser light emitted from the laser diode on the signal surface of the disk 1 based on the signal obtained from the photodetector 4 incorporated in the optical pickup 2, and the laser light as a signal. A pickup control circuit that performs a tracking control operation to follow a signal track on a surface, and is configured to output a tracking control signal based on a tracking error signal and a focusing control signal based on a focus error signal.

  Reference numeral 9 denotes a tracking coil driving circuit to which a tracking control signal output from the pickup control circuit 8 is input, and is configured to supply a driving signal to the tracking coil 6 incorporated in the optical pickup 2. . Reference numeral 10 denotes a focusing coil driving circuit to which a focusing control signal output from the pickup control circuit 8 is input, and is configured to supply a driving signal to the focusing coil 5 incorporated in the optical pickup 2. .

  Reference numeral 11 denotes an RF signal amplifying circuit which receives an RF signal obtained from the photodetector 4 incorporated in the optical pickup 2 and amplifies the signal, and outputs an RF signal having the waveform shown in FIG. It is configured. Reference numeral 12 denotes a peak level detection circuit to which an RF signal output from the RF signal amplification circuit 11 is input, and is configured to detect the level indicated by the upper solid line P in the waveform diagram shown in FIG. Has been. Reference numeral 13 denotes a bottom level detection circuit to which an RF signal output from the RF signal amplification circuit 11 is input, and is configured to detect a level indicated by a lower solid line Q, that is, a bottom level in the waveform diagram shown in FIG. Has been.

  14 is a signal detected and output by the peak level detection circuit 12 and the bottom level detection circuit 13, that is, a peak level and a bottom level value obtained from the RF signal are input and output from the focusing coil drive circuit 10. A tilt control circuit for performing a tilt control operation based on a tilt adjustment signal obtained from the drive signal, and a tilt coil drive circuit whose operation is controlled by a signal output from the tilt control circuit. A tilt adjustment drive signal is supplied to a tilt adjustment coil 7 incorporated in the optical pickup 2.

  Reference numeral 16 denotes an offset detection circuit that is in an operation state during an offset value detection operation performed before the recording operation. The tilt control circuit 14 tilts the tilt coil drive circuit 15 stepwise, that is, the objective lens with respect to the disk 1 is moved. A signal for causing the tilt adjustment coil 7 to output a drive signal for offset detection for changing the tilt is output. Reference numeral 17 denotes a memory circuit for storing an offset value detected by an offset value detection operation, which will be described later, and is added to a tilt adjustment signal obtained from the focusing coil drive circuit 10 when performing a tilt control operation in the recording / reproducing operation state. The tilt control circuit 14 is configured to generate the offset signal based on the offset value stored in the memory circuit 17.

Reference numeral 18 denotes a laser drive circuit for supplying a drive signal to the laser diode 3 incorporated in the optical pickup 2. Reference numeral 19 encodes a signal for recording a recording signal on the disk 1 and supplies the signal to the laser drive circuit 18. It is a signal recording circuit and is configured to output an offset adjustment signal during an offset value detection operation.

  As described above, the optical disk recording / reproducing apparatus according to the present invention is configured. Next, the operation will be described. In a state where a normal recording operation or reproduction operation is performed, a focus error signal or a tracking error signal is generated from a signal obtained from the photodetector 4 incorporated in the optical pickup 2, and the generated error signal is generated. The pickup control circuit 8 performs a control operation for performing a focusing control operation and a tracking control operation based on the control.

  When each control operation by the pickup control circuit 8 is performed, a control signal is output from the pickup control circuit 8 to the focusing coil drive circuit 10 and the tracking coil drive circuit 9. As a result, a driving signal is supplied from the focusing coil driving circuit 10 and the tracking coil driving circuit 9 to the focusing coil 5 and the tracking coil 6. Such a drive signal displaces the objective lens in a direction to reduce the level of the focus error signal or tracking error signal, so that focusing control for focusing the laser light emitted from the optical pickup 2 on the signal surface on the disk 1 It is possible to perform a tracking control operation that follows the operation and the signal track.

  As described above, the focusing control operation and tracking control operation by the pickup control circuit 8 are performed. Next, the tilt control method which is the gist of the present invention will be described.

  In the optical disc recording / reproducing apparatus according to the present invention, an offset value setting operation necessary for accurately performing the tilt control operation is performed before performing the recording operation. In the operation for such setting, a signal for performing an operation for setting an offset value from the offset detection circuit 16 to the tilt control circuit 14 is output.

  Such an operation is a control operation in which a control signal for changing the tilt angle step by step is output from the tilt coil driving circuit 15 to the tilt adjusting coil 7 step by step in a state where the normal tilt control operation is not performed. Is done. When such a control signal is output from the tilt control circuit 14, the tilt of the objective lens from the tilt coil driving circuit 15 to the tilt adjusting coil 7 is stepped from the position where the objective lens is most inclined to the other direction. A drive signal for offset detection for changing is supplied. As a result, the objective lens is tilted step by step in the direction of tilt adjustment by the drive operation of the tilt adjustment coil 7.

  During the offset value detection operation, as described above, the operation of changing the tilt of the objective lens step by step by the signal output from the offset detection circuit 16 is performed. This operation is performed on the inner circumference side of the disc 1. This is performed while recording the offset adjustment signal in the provided inner circumference side trial writing area A and outer circumference side trial writing area D.

  First, a case where an offset adjustment signal is recorded in the inner circumference side trial writing area A in order to set the inner circumference side offset value will be described. The operation of outputting an offset adjustment signal from the signal recording circuit 19 to the laser driving circuit 18 and recording the signal in the test writing area A on the inner circumference side of the disk 1 by the laser light emitted from the laser diode 7 is tilted. This is done while changing the angle step by step. When such an offset adjustment signal recording operation is performed, the relationship between the recording position and the level of the signal output from the offset detection circuit 16 is stored in the memory circuit 17 or the like.

  When the objective lens tilt changing operation based on the signal output from the offset detection circuit 16 is completed, the recording operation of the offset adjustment signal on the disk 1 is also stopped. When such an operation is completed, the optical pickup 2 is moved to the position where the recording operation of the offset adjustment signal in the inner periphery side test writing area A is started, and then the recorded offset adjustment signal is reproduced. Such a reproduction operation is performed in a state where a drive signal is not supplied to the tilt adjustment coil 7, that is, in a state where the objective lens is in a neutral position.

  When the recorded offset adjustment signal is reproduced while changing the angle of the objective lens with respect to the disk 1, the level of the RF signal obtained from the laser light reflected from the disk 1 changes. The offset adjustment signal recorded in the inner periphery side trial writing area A of the disk 1 is amplified by the RF signal amplification circuit 11 and then input to the peak level detection circuit 12 and the bottom level detection circuit 13.

  As the inclination of the optical pickup 2 with respect to the signal surface of the disk 1 is adjusted in the correct direction, the peak level in the RF signal increases and the bottom level decreases on the contrary. Therefore, when the recorded offset adjustment signal is changed while the tilt is changed stepwise, the peak level decreases after reaching the maximum and the bottom level increases after reaching the minimum.

  When the recorded offset adjustment signal is reproduced while stepwise changing the level of the drive signal supplied to the tilt adjustment coil 7, the peak level and the bottom level of the RF signal as the reproduction signal change. Will do. When the drive voltage at the position where the offset adjustment signal at which the peak level is maximized is recorded or the position at which the offset adjustment signal at which the bottom level is minimized is recorded is supplied to the tilt adjustment coil 7, tilt is performed. An operation of storing the value of the control signal output from the control circuit 14 in the memory circuit 17 as the inner peripheral offset value is performed.

  The setting operation of the inner periphery side offset value described above is a case of utilizing the characteristic that the peak level of the RF signal is maximized or the bottom level is minimized. You can also use the difference. That is, when a signal recorded with the objective lens tilt optimally on the signal surface of the disk 1 is reproduced, there is a characteristic that the difference between the peak level and the bottom level becomes the largest, so this difference becomes the largest. When the drive voltage at the position where the offset adjustment signal is recorded is supplied to the tilt adjustment coil 7, the value of the control signal output from the tilt control circuit 14 is stored in the memory circuit 17 as the inner peripheral offset value. Operation is performed.

  As described above, the setting operation of the inner periphery side offset value using the inner periphery side test writing area A is performed. In the present invention, the outer periphery side test writing area D provided on the outer periphery side of the disk 1 is set. The setting operation of the outer periphery side offset value is performed. Such an operation is performed by moving the optical pickup 2 to the outer peripheral side test writing area D based on the position information data recorded as a wobble signal on the disk 1 and then the offset value in the inner peripheral side test writing area A described above. Since it can be performed by performing the same operation as the detection operation, the description thereof is omitted. Then, the outer periphery side offset value set in the outer periphery side test writing area D is stored in the memory circuit 17.

  As described above, the inner peripheral offset value and the outer peripheral offset value are stored in the memory circuit 17. Next, the tilt adjustment operation will be described.

When the optical disk recording / reproducing apparatus is in a reproduction state or a recording state, when the relationship between the optical pickup 2 and the disk 1 needs to be adjusted, tilt adjustment coil 7
A drive signal for changing the tilt of the objective lens is supplied from the tilt drive circuit 15. The adjustment operation of the tilt adjustment signal for changing the tilt is supplied from the focusing coil drive circuit 10 to the focusing coil 5. The driving signal is used.

  The drive signal supplied to the focusing coil 5 from the focusing coil drive circuit 10 is a signal in which an AC signal is superimposed on a DC voltage. That is, the DC voltage is a signal for displacing the position of the objective lens to the operating position, and the AC signal is a signal for displacing the objective lens by following the fast movement of the disk 1. The DC voltage described above is a signal for displacing the objective lens to the operating position in accordance with the positional relationship between the signal surface of the disk 1 and the optical pickup 2, and tilt adjustment is performed by utilizing the change in the DC voltage. I can do it.

  That is, since the DC voltage included in the drive signal supplied to the focusing coil 5 indicates the positional relationship between the objective lens and the signal surface of the disk 1, the DC voltage that changes corresponding to the position change on the disk. Indicates the tilt relationship between the objective lens and the disk 1. Accordingly, a change in the DC voltage included in the drive signal supplied from the focusing coil drive circuit 10 to the focusing coil 5 is extracted as a tilt adjustment signal, and the extracted signal is stored in the memory circuit 17. The tilt adjustment operation can be performed by supplying the tilt coil driving circuit 15 with a signal obtained by adding the offset value calculated from the peripheral offset value and the offset value calculated as the peripheral offset value as a tilt control signal.

  The offset value added to the signal extracted from the focusing coil drive circuit 10 is calculated and set according to the recording position from the inner peripheral offset value and the outer peripheral offset value. That is, the position on the outer periphery side test writing area D where the outer periphery side offset value is set and the position on the inner periphery side test writing area A where the inner periphery side offset value is set are obtained from the position information data. The optimum offset value at the position on the disk 1 can be calculated from the distance between them and the change in the offset value.

  As a result of the tilt adjustment operation described above, the tilt coil drive circuit 15 supplies the tilt adjustment drive signal with the optimum tilt adjustment to the recording / reproducing position to the tilt adjustment coil 7. An operation for adjusting the angle to an optimum state, that is, a tilt adjustment operation can be accurately performed.

  In the present embodiment, the case where a disc in which the outer peripheral side test writing area D is provided on the outer peripheral side of the signal recording area C has been described. However, in the case of a disc in which the outer peripheral side test writing area D is not provided. The spare area provided as a spare at the outer peripheral side of the signal recording area C, that is, the outermost peripheral position can be used.

  In the present embodiment, the tilt adjustment signal is obtained from the drive signal supplied to the focusing coil 5. However, the tilt adjustment signal is used for an apparatus configured to perform tilt adjustment using the level change of the RF signal. You can also

It is a circuit diagram which shows one Example of the optical disk recording / reproducing apparatus based on this invention. It is a signal waveform diagram for demonstrating operation | movement of this invention. It is a top view which shows the disk based on this invention.

Explanation of symbols

1 disc
2 Optical pickup
3 Laser diode
4 photodetectors
5 Focusing coil
6 Tracking coil
7 Coil for tilt adjustment
DESCRIPTION OF SYMBOLS 8 Pickup control circuit 10 Focusing coil drive circuit 11 RF signal amplification circuit 12 Peak level detection circuit 13 Bottom level detection circuit 14 Tilt control circuit 15 Tilt coil drive circuit 16 Offset detection circuit 17 Memory circuit 18 Laser drive circuit 19 Signal recording circuit

Claims (5)

A tilt control method for an optical disc recording / reproducing apparatus using an optical pickup equipped with a tilt adjustment coil for adjusting the tilt of an objective lens. The tilt adjustment coil is provided in a test writing area provided on the inner circumference side of the disc The offset adjustment signal is recorded while changing the level of the offset detection drive signal to be supplied, and then the recorded offset adjustment signal is reproduced and the peak level of the reproduced RF signal is detected and detected. Set the level of the drive signal supplied to the tilt adjustment coil when recording a signal with the maximum peak level as the inner offset value, and then tilt it to the outer peripheral position of the signal recording area on the disc. Record the offset adjustment signal while changing the level of the offset detection drive signal supplied to the adjustment coil. After that, the recorded offset adjustment signal is reproduced, the peak level of the reproduced RF signal is detected, and the signal with the maximum detected peak level is recorded. The drive signal level is set as the outer peripheral offset value, and the tilt adjustment signal for tilt control is added by adding the offset value corresponding to the recording position calculated from the inner peripheral offset value and the outer peripheral offset value to the tilt adjustment signal. A tilt control method for an optical disc recording / reproducing apparatus, wherein control is performed. A tilt control method for an optical disc recording / reproducing apparatus using an optical pickup equipped with a tilt adjustment coil for adjusting the tilt of an objective lens. The tilt adjustment coil is provided in a test writing area provided on the inner circumference side of the disc The offset adjustment signal is recorded while changing the level of the offset detection drive signal to be supplied, and then the recorded offset adjustment signal is reproduced, and the bottom level of the reproduced RF signal is detected and detected. Set the level of the drive signal supplied to the tilt adjustment coil when recording a signal with the lowest bottom level as the inner peripheral offset value, and then tilt it to the outer peripheral position of the signal recording area provided on the disc Record the offset adjustment signal while changing the level of the offset detection drive signal supplied to the adjustment coil. After that, the recorded offset adjustment signal is reproduced, the bottom level of the reproduced RF signal is detected, and the signal that minimizes the detected bottom level is recorded and supplied to the tilt adjustment coil. The drive signal level is set as the outer peripheral offset value, and the tilt adjustment signal for tilt control is added by adding the offset value corresponding to the recording position calculated from the inner peripheral offset value and the outer peripheral offset value to the tilt adjustment signal. A tilt control method for an optical disc recording / reproducing apparatus, wherein control is performed. A tilt control method for an optical disc recording / reproducing apparatus using an optical pickup equipped with a tilt adjustment coil for adjusting the tilt of an objective lens. The tilt adjustment coil is provided in a test writing area provided on the inner circumference side of the disc The offset adjustment signal is recorded while changing the level of the offset detection drive signal to be supplied, and then the recorded offset adjustment signal is reproduced, and the peak level and the bottom level of the reproduced RF signal are detected. The level of the drive signal supplied to the coil for tilt adjustment when a signal that maximizes the difference between the detected peak level and bottom level is recorded is set as the inner peripheral offset value, and is further provided on the disc. The level of the drive signal for offset detection supplied to the tilt adjustment coil is changed to the outer periphery of the signal recording area. After the offset adjustment signal is recorded, the recorded offset adjustment signal is reproduced, the peak level and bottom level of the reproduced RF signal are detected, and the difference between the detected peak level and bottom level is detected. Set the level of the drive signal supplied to the coil for tilt adjustment when the signal that maximizes is recorded as the outer offset value, and the inner offset value and the outer offset value in the tilt adjustment signal for tilt control A tilt control method for an optical disc recording / reproducing apparatus, wherein tilt control is performed by adding an offset value corresponding to a recording position calculated from 4. A disk having a test writing area at an outer peripheral position, the setting operation of the outer peripheral offset value is performed in the test writing area at the outer peripheral position. Tilt control method. 2. The disk having no test writing area at the outer peripheral position, the setting operation of the outer peripheral offset value is performed in a spare area provided outside the signal recording area. The tilt control method according to claim 3.

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