JP2005050394A - Optical disk unit, focal offset adjustment method and focal offset adjustment program therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a focal offset setting technique realizing stable recording even to an unrecorded disk in an optical disk unit. <P>SOLUTION: Test writing is performed in a predetermined area of an optical disk by obtaining a maximum signal amplitude position and a minimum reproduced error signal position of an RF signal by varying a focal offset, setting the focal offset between both positions, and controlling an optical head based on the set focal offset. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for adjusting a focus offset in an optical disc apparatus.
[0002]
[Prior art]
As a prior art related to the present invention, there is one described in Japanese Patent Laid-Open No. 6-139583 (Patent Document 1), for example. In this publication, in order to obtain an appropriate focus offset in an optical disc apparatus, a focus servo is placed between the offset amount at which the modulation degree of the reproduction signal is maximized and the offset amount at which the peak value of the tracking error signal is maximized. A configuration for setting the offset amount is described.
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 6-139583
[0004]
[Problems to be solved by the invention]
In the above prior art, a reproduction operation for obtaining a reproduction signal is required. For this reason, it cannot be applied to an optical disc that cannot be reproduced, that is, an unrecorded disc. When performing continuous recording, the data in the recorded area is read, and recording is started based on the data. In the apparatus, the conventional amount of focus offset is not in a state suitable for reproduction, and there are many reproduction errors, and data in the recorded area cannot be read, and there is a possibility that continuous recording cannot be performed.
The problem of the present invention is that, in view of the situation of the above-mentioned prior art, in an optical disc apparatus, even a completely unrecorded disc having only groove information can be recorded with good wobble information including splice recording. To achieve the focus offset.
An object of the present invention is to provide a technique capable of solving such problems.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, in the present invention, basically, in an optical disc apparatus, the focus offset is varied to obtain the maximum position of the signal amplitude of the RF signal and the minimum position of the reproduction error signal. A focus offset position is set, the optical head is controlled based on the set focus offset, and trial writing is performed on a predetermined area of the optical disc prior to recording. Specifically, the present invention proposes an optical disc apparatus having the above-mentioned basic requirements, a focus offset adjustment method thereof, and a focus offset adjustment program.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
1 to 3 are explanatory views of a first embodiment of the present invention. FIG. 1 is a diagram showing a configuration example of an optical disc apparatus as a first embodiment of the present invention, FIG. 2 is an operation example diagram of focus offset adjustment in the optical disc apparatus of FIG. 1, and FIG. 3 is a focus in the optical disc apparatus of FIG. It is explanatory drawing of the setting position of offset.
[0007]
In FIG. 1, 1 is an optical disk, 2 is an optical head that irradiates the optical disk 1 with laser light, and records data on the optical disk 1 or reads recorded data. , 4 is a spindle motor for rotationally driving the optical disc 1, 6 is a laser power control circuit as a recording power control means for controlling the power of the laser light emitted from the optical head 2, 7 is a modulation circuit that modulates identification data for identifying the optical disc 1, and 8 is a focus error signal and tracking for controlling the optical head from a signal read from the optical disc 1 by the optical head 2 (hereinafter referred to as a read signal). From focus error detection circuit and tracking error detection circuit to detect servo error signal which is error signal A servo signal detection circuit 9 for filtering the servo error signal from the servo signal detection circuit 8 and controlling the optical head 2 so that the laser beam is focused at a predetermined position on the optical disc 1. An optical head control circuit 10 serving as a head control means is used for detecting reproduction error information such as a C1 error in a CD, a PI error in a DVD, and a phase error amount of data PLL from a reproduction signal. A detection circuit, 11 is a reproduction signal demodulation circuit that demodulates an RF signal from a read signal of the optical head 2, and 12 is a device that includes a microcomputer and controls the entire apparatus including setting of a focus offset as focus offset setting means The control circuit 13 receives an OPC (Optimum Power Calibration) from the read signal of the optical head 2. on) (an OPC information detection circuit for detecting information (OPC information) for performing trial writing of data in the trial writing area of the optical disc 1 and obtaining the optimum recording power by evaluating the trial written data) An address information demodulating circuit that demodulates address information that is data recording position information from a read signal of the optical head 2, 15 is a tracking offset variable circuit that varies the tracking offset, and 16 is a focus offset variable circuit that varies the focus offset. is there.
[0008]
In the above configuration, the optical disk 1 is rotated at a predetermined rotational speed by the spindle motor 4. Laser light controlled to a predetermined light emission power by the laser power control circuit 6 is emitted from the optical head 2 toward the optical disk surface in the rotating state. The movement position of the optical head 2 is controlled by the optical head control circuit 9 and the sled mechanism 3, and the emitted laser light is irradiated to a predetermined position on the optical disk 1. Reflected light from the optical disc 1 is received by the optical head 2 and information recorded on the optical disc 1 is read out as a signal. From the read signal (read signal), an RF signal, an address signal, a servo error signal for controlling the optical head (focus error signal, tracking error signal), and the like are obtained. The RF signal is input to the reproduction signal demodulation circuit 11, and the address signal is input to the address information demodulation circuit 14 and demodulated. The demodulated RF signal is input to the device control circuit 12. The servo error signal is input to a servo signal detection circuit 8, and the servo signal detection circuit 8 detects a focus error signal and a tracking error signal. In addition to the demodulated RF signal, a disk ID is output from the reproduction signal demodulating circuit 11 and input to the device control circuit 12. The optical head control circuit 9 controls the optical head 2 according to the servo error signal obtained from the servo signal detection circuit 8.
[0009]
When data is recorded on the optical disk 1, the optical head control circuit 9 controls the optical head 2 according to a command from the apparatus control circuit 12, and the laser beam is condensed at a predetermined position of the optical disk 1 to be recorded. The recording data is sent from the apparatus control circuit 12 to the modulation circuit 7 and converted into data suitable for recording on the optical disc 1. Next, laser light having an emission intensity corresponding to the data is output from the optical head 2, and data is recorded on the optical disk 1.
[0010]
The OPC information detection circuit 13 detects the light reflected from the optical disk when the recording is performed while changing the recording power and when the recorded area is reproduced, by converting the reflected light into an electric signal. For example, when the optical disc 1 is a CD-R, the OPC information detection circuit 13 detects the signal level of the electric signal converted from the reflected light at the time of recording, and is converted from the reflected light of the recording mark and space at the time of reproduction. The signal level of the detected electrical signal is detected. For example, in the case of recording in the case of a CD-R, in the case of an optical disk to be used for the first time (unrecorded disk), OPC by trial writing is performed in order to properly record data. By performing OPC, the optimum recording power and the electric signal level by the reflected light at that time are obtained.
[0011]
During recording, the focus offset is adjusted before the OPC. The focus offset is adjusted by setting the focus offset amount to a value suitable for both recording and reproduction by the apparatus control circuit 12. When setting the focus offset, if the target optical disc is not an unrecorded disc and the recorded portion can be reproduced, the focus offset variable circuit 16 basically changes the focus offset amount. Thus, the focus offset position where the amplitude of the RF signal based on the output of the optical head 2 is maximized and the focus offset position where the reproduction error signal is minimized are obtained, and the focus offset is set between the obtained positions. It is set by the control circuit 12. The device control circuit 12 further controls the optical head 2 via the optical head control circuit 9 based on the set focus offset. Test writing is performed on a predetermined area of the optical disc 1 with the controlled optical head, and OPC is executed. After OPC execution, recording or connection recording is performed. Further, when the target optical disk is not an unrecorded disk and an already recorded portion cannot be reproduced, the focus offset amount is varied by the focus offset variable circuit 16, thereby being based on the output of the optical head 2. A focus offset position at which the amplitude of the RF signal is maximized is obtained, and the focus offset position is set by the apparatus control circuit 12 between the obtained focus offset position and the focus offset position at which the offset of the focus error detection circuit becomes zero. .
[0012]
On the other hand, during reproduction, the focus offset is set so that the reproduction error signal is minimized. When the minimum of the reproduction error signal cannot be obtained, a focus offset at which the focus error detection circuit offset is zero is set. In particular, since a reproduction signal cannot be obtained on an unrecorded disc, a focus offset position where the amplitude of the tracking error signal is maximized and a focus offset position where the focus error detection circuit offset is zero are obtained. The apparatus control circuit 12 sets a focus offset (first focus offset), performs test writing in the test writing area under the set focus offset, and then reproduces the area so that the amplitude of the RF signal is maximized. And a focus offset that minimizes the reproduction error signal. If the focus offset that maximizes the RF signal amplitude or the minimum reproduction error signal cannot be obtained, such as when recording by trial writing is not performed, the focus offset during reproduction is the focus error detection. The focus offset is set so that the circuit offset becomes zero. Also, since the recording power is recorded in the trial writing area with variable recording quality, the quality of the reproduction signal is not uniform. Therefore, recording is performed in the trial writing area with the power obtained by OPC, and recording is performed in the area. A focus offset that maximizes the amplitude of the RF signal and minimizes the reproduction error signal may be obtained.
[0013]
FIG. 2 is a diagram illustrating an operation example of focus offset adjustment during recording in the optical disc apparatus of FIG. The same reference numerals as those in FIG. 1 are used for the components in FIG. 1 used in the description of FIG.
In FIG. 2, the focus offset adjustment operation is as follows.
(1) A recording mode instruction is issued (step S201).
(2) It is determined whether or not the target optical disc is an unrecorded disc (step S202).
(3) As a result of the determination in step S202, if the disc is an unrecorded disc, the focus offset amount is varied by the focus offset variable circuit 16, and the focus offset position where the amplitude of the tracking error signal is maximized, and the focus error A focus offset position at which the detection circuit offset becomes zero is obtained, and a focus offset (first focus offset) is set between the two positions by the apparatus control circuit 12 (step S203). At this time, when the focus offset position where the amplitude of the tracking error signal is maximum is within a certain amount of deviation from the focus offset position where the focus error detection circuit offset is zero, the focus error detection circuit offset is zero. The focus offset position may be set as follows.
(4) Based on the set focus offset, the apparatus control circuit 12 controls the optical head 2 via the optical head control circuit 9. Trial writing is performed on a predetermined area of the optical disc 1 with the controlled optical head, and OPC is executed (step S204). This is because if the deviation of the focus offset is large, a recording mark may not be formed if recording is performed with a preset reference recording power (default power).
(5) Further, a plurality of sectors are recorded with the controlled recording power (step S205). That is, the same sector as OPC is distributed and recorded in the next OPC area. Since processing can be performed in the same manner as OPC, it is not necessary to add special processing.
[0014]
(6) By varying the focus offset amount by the focus offset variable circuit 16, the amplitude of the RF signal based on the output of the optical head 2 and the reproduction error signal are measured (step S206). The focus offset amount is varied by dividing the focus offset position where the amplitude of the tracking error signal becomes maximum and the focus offset position where the focus error detection circuit offset becomes zero, for example, into five. Instead of a playback error signal (for example, CD C1 error, DVD PI error, playback error rate, PLL phase error detection signal indicating playback jitter, etc.), the playback signal jitter or error rate may be used. However, the measurement is performed after the PLL is stably synchronized.
(7) Based on the measurement result in step S206, the focus offset position where the amplitude of the RF signal is maximized and the focus offset position where the reproduction error signal is minimized are obtained, and the focus offset ( The second focus offset) is set by the apparatus control circuit 12 (step S207). When the focus offset position at which the amplitude of the RF signal becomes maximum cannot be obtained, the focus offset position at which the amplitude of the tracking error signal becomes maximum is used instead. When the focus offset position where the reproduction error signal is minimized cannot be obtained, the focus offset position where the focus error detection circuit offset is zero is used instead.
(8) The apparatus control circuit 12 further controls the optical head 2 via the optical head control circuit 9 based on the set focus offset, performs test writing on a predetermined area of the optical disc 1 and executes OPC ( Step S208).
(9) Next, it is determined whether or not the connection recording (link recording) is performed (step S209).
(10) In the case of connection recording (link recording), the information of the connection destination (link destination) is reproduced (step S210).
[0015]
(11) Thereafter, predetermined information is recorded at a predetermined position (step S211).
(12) As a result of the determination in step S209, if it is not continuous recording (link recording), the process proceeds to step S211 and predetermined information is recorded at a predetermined position.
(13) If the recording target optical disk is not an unrecorded disk in the determination in step S202, it is determined whether or not the already recorded portion can be reproduced (step S212).
(14) If the recorded portion can be reproduced as a result of the determination in step S212, the focus offset amount is varied by the focus offset variable circuit 16 in the same manner as in step S206, so that the amplitude and reproduction of the RF signal are reproduced. The error signal is measured (step S213). The focus offset amount is varied by dividing the focus offset position where the amplitude of the tracking error signal becomes maximum and the focus offset position where the focus error detection circuit offset becomes zero, for example, into five. Instead of a playback error signal (for example, CD C1 error, DVD PI error, playback error rate, PLL phase error detection signal indicating playback jitter, etc.), the playback signal jitter or error rate may be used. However, the measurement is performed after the PLL is stably synchronized.
(15) Based on the measurement result of step S213, the focus offset position where the amplitude of the RF signal is maximized and the focus offset position where the reproduction error signal is minimized are obtained, and the focus offset ( A second focus offset) is set by the apparatus control circuit 12 (step S214). When the focus offset position at which the amplitude of the RF signal becomes maximum cannot be obtained, the focus offset position at which the amplitude of the tracking error signal becomes maximum is used instead. When the focus offset position where the reproduction error signal is minimized cannot be obtained, the focus offset position where the focus error detection circuit offset is zero is used instead.
[0016]
(16) Thereafter, through OPC execution in step S208, determination of whether or not to perform connection recording in step S209, and reproduction of the connection destination in step S210, predetermined information is recorded in a predetermined position in step S211 or After the determination in step S209, the process proceeds to the recording operation in step S211 to record predetermined information at a predetermined position on the disc.
(17) Further, as a result of the determination in step S212, if the already recorded portion cannot be reproduced, the focus offset amount is varied by the focus offset variable circuit 16 and the amplitude of the RF signal is measured (step S215). ).
(18) Based on the measurement result of step S215, a focus offset position where the amplitude of the RF signal is maximum and a focus offset position where the focus error detection circuit offset is zero are obtained, and the focus is between the obtained positions. An offset (third focus offset) is set by the apparatus control circuit 12 (step S216). When the focus offset position at which the amplitude of the RF signal becomes maximum cannot be obtained, the focus offset position at which the amplitude of the tracking error signal becomes maximum is used instead.
(19) After that, as in (16) above, through OPC execution in step S208, determination as to whether or not to perform connection recording in step S209, and reproduction of the connection destination in step S210, predetermined information is stored in a predetermined position in step S211. Or after the determination in step S209, the process proceeds to a recording operation in step S211 to record predetermined information at a predetermined position on the disc.
[0017]
In the case of reproduction, the focus offset is set so that the reproduction error signal is minimized during reproduction of normal recording data other than during link operation or OPC reproduction. When the minimum reproduction error signal cannot be obtained, the focus offset is set so that the focus error detection circuit offset becomes zero.
[0018]
All the operations in the focus offset adjustment, focus offset setting, OPC execution, recording start and the like are all performed by the microcomputer in the apparatus control circuit 12 executing the procedure of the operation according to a preset program. Done. It is assumed that the program is stored in advance in a memory in the optical disk device or a connected host computer.
[0019]
FIG. 3 is an explanatory diagram of a focus offset setting position in the optical disc apparatus of FIG. Also in FIG. 3, the same reference numerals as those in FIG. 1 are used for the components in FIG. 1 used in the description.
In FIG. 3, (1) is a characteristic curve of OPC power, (2) is a characteristic curve of CD C1 error, (3) is a characteristic curve of Atip jitter, (4) is a characteristic curve of amplitude of RF signal, (5) ▼ is a characteristic curve of the amplitude of the tracking error signal (Push-Pull signal). All the characteristics are expressed with the focus offset amount on the horizontal axis. Point A on the characteristic curve (5) is the maximum amplitude of the tracking error signal, point B on the characteristic curve (4) is the maximum amplitude of the RF signal, and point C on the characteristic curve (2) is the reproduction. The minimum point of the error signal, D, is the point where the focus error detection circuit offset is zero. The Tip information (time information, recording power setting information, recording pulse information, etc.) encoded in the wobble signal in the characteristic curve {circle around (3)} is reproduced better as the Tip jitter is smaller. Obtaining a wobble signal with good quality enables normal rotation control during recording and allows normal recording in a state where increase in recording power is suppressed. On the other hand, in the area where the reproduction error such as the C1 error is small, the recorded data is reproduced favorably.
[0020]
In the present invention, in order to reproduce Atip jitter satisfactorily and perform recording operation in a satisfactory state, and also to reproduce recording data satisfactorily, the focus offset is set to A in FIG. -D, B-C or B-D. That is, in step S203 in FIG. 2, the first focus offset is set to a value between A and D in FIG. 3, and in step S207 and step S214, the second focus offset is set. A value between B and C is set, and in step S216, the third focus offset is set to a value between B and D. Thereby, stable recording and reproduction are possible.
[0021]
According to the first embodiment, in the optical disc apparatus, even a completely unrecorded disc having only groove information can be stably recorded in a state where wobble information is good including splice recording. Also, stable reproduction is possible.
[0022]
FIG. 4 is a diagram showing an example of the configuration of an optical disc apparatus as a second embodiment of the present invention. The second embodiment is different from the first embodiment in that first and second memories connected to the device control circuit and an arithmetic unit are provided.
In FIG. 4, reference numeral 17 denotes a focus offset position set between the maximum point of the RF signal amplitude (point B in FIG. 3) and the minimum point of the reproduction error signal (point C in FIG. 3). A first memory 18 for storing a deviation from the maximum amplitude of the tracking error signal (point A in FIG. 3), 18 is the tracking error signal of the minimum point (point C in FIG. 3) of the reproduction error signal. A second memory 19 for storing a deviation from the maximum amplitude point (point A in FIG. 3), 19 stores the optimum recording power at the position stored in the first memory 17 and the second memory 18. This is an arithmetic unit for calculating the optimum recording power at the position where the recording is performed. The structure of the other parts is the same as that of the first embodiment shown in FIGS.
[0023]
In the configuration of FIG. 4 described above, for example, at the time of manufacturing the apparatus, the focus offset is changed by the focus offset variable circuit 16, and the maximum point of the tracking error signal, the maximum point of the RF signal, and the minimum point of the reproduction error signal are determined. The first memory 17 stores the offset of the intermediate value between the maximum point of the amplitude of the RF signal and the minimum point of the reproduction error signal from the maximum point of the amplitude of the tracking error signal. deep. When recording on the disc, the focus offset is changed by the focus offset variable circuit 16 at the time of starting the disc, and an offset value at which the amplitude of the tracking error signal is maximized is obtained and stored in the first memory 17. The correction offset amount is added, and the offset amount after the addition is set as the focus offset amount at the time of recording. The intermediate value may be shifted to either side as long as the apparatus can perform stable recording and reproduction. Further, the second memory 18 stores how much the minimum point of the reproduction error signal is offset from the maximum amplitude of the tracking error signal, and when recording on the disk, when the disk is started, The focus offset is changed by the focus offset variable circuit 16 to obtain an offset value that maximizes the amplitude of the tracking error signal, and the correction offset amount stored in the second memory 18 is added to the offset value, and the offset after the addition is added. The amount is the focus offset amount at the time of recording. As a result, it is possible to perform good reproduction without performing offset adjustment particularly during reproduction.
[0024]
The address information demodulating circuit 14 has a function of correcting an error at the time of address demodulation, and has a configuration capable of performing correct demodulation even when there is an error due to poor signal quality. By using this error correction function, it is possible to search for a position where the reproduction error signal of the address information is minimized by changing the focus offset during recording. In this case, for example, when the apparatus is manufactured, the focus offset amount is changed by the focus offset variable circuit 16, and the address of the tracking error signal, the maximum point of the amplitude of the RF signal, the maximum point of the amplitude of the RF signal, and the minimum point of the reproduction error signal are combined. The minimum point of the reproduction error signal of the information is also measured, and the intermediate value between the minimum point of the reproduction error signal of the address information and the minimum point of the reproduction error signal is changed from the maximum point of the amplitude of the tracking error signal. The offset is stored in the first memory 17. When recording on the disc, the focus offset is changed by the focus offset variable circuit 16 at the time of starting the disc, and an offset value at which the amplitude of the tracking error signal is maximized is obtained and stored in the first memory 17. The correction offset amount is added, and the offset amount after the addition is set as the focus offset amount at the time of recording. The intermediate value may be shifted to either side as long as the apparatus can perform stable recording and reproduction.
[0025]
In some cases, the correction amount recorded in the first memory 17 and the second memory 18 can be stably recorded and reproduced even if the correction amount is fixed in each device or each optical disk medium. In this case, a correction amount may be set in advance in a program of a microprocessor that controls the apparatus, and may be recorded in the first memory 17 and the second memory 18.
[0026]
According to the second embodiment, by storing an appropriate focus offset at the time of recording in the first memory 17 in advance, it is possible to shorten the time until the start of recording. Further, as in the case of the first embodiment, stable recording can be performed even on a completely unrecorded disc in a state where wobble information is good, including continuous recording. Also, stable reproduction is possible.
[0027]
【The invention's effect】
According to the present invention, stable recording and reproduction can be performed on an unrecorded disc in the optical disc apparatus.
[Brief description of the drawings]
FIG. 1 is a configuration example diagram of a first embodiment of the present invention.
2 is an operation example diagram of focus offset adjustment in the configuration of FIG. 1; FIG.
FIG. 3 is an explanatory diagram of a focus offset setting position in the configuration of FIG. 1;
FIG. 4 is a configuration example diagram of a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Optical disk 2 ... Optical head 3 ... Thread mechanism 4 ... Spindle motor 6 ... Laser power control circuit 7 ... Modulation circuit 8 ... Servo signal detection circuit 9 ... Optical head control circuit 10 ... Reproduction error Information detecting circuit 11... Reproduction signal demodulating circuit 12... Device control circuit 13. OPC information detecting circuit 14. Address information demodulating circuit 15 Tracking variable variable circuit 16 Focus offset variable circuit 17 First Memory 18 ... Second memory 19 ... Calculator.

Claims (8)

An optical disc apparatus that records and / or reproduces information on an optical disc,
An optical head that records or reads information by irradiating the optical disk with laser light;
Means for varying the focus offset, obtaining the maximum signal amplitude of the RF signal and the minimum reproduction error signal based on the output of the optical head, and setting the focus offset between the two;
Optical head control means for controlling the optical head based on the set focus offset;
Trial writing playback means for performing trial writing in the trial writing area of the recording medium;
Laser power discrimination means for discriminating the power of laser light suitable for data recording based on the trial writing reproduction information obtained from the test book reproduction means,
Recording power control means for controlling the recording power based on the laser power discrimination means;
An optical disc apparatus characterized by performing trial writing on a predetermined area of the optical disc with the setting of the focus offset prior to recording or joint recording of information on the optical disc. An optical disc apparatus that records and / or reproduces information on an optical disc,
An optical head that records or reads information by irradiating the optical disk with laser light;
Change focus offset, all or part of maximum tracking error signal amplitude, focus error detection circuit offset zero, maximum signal amplitude of RF signal based on optical head output, minimum reproduction error signal A first focus offset is set between the maximum amplitude of the tracking error signal and the focus error detection circuit offset zero, and the maximum signal amplitude of the RF signal and the minimum of the reproduction error signal are set. A second focus offset, and a focus offset setting means for setting a third focus offset between the maximum signal amplitude of the RF signal and the focus error detection circuit offset;
An optical head control means for controlling the optical head based on the set first and second focus offsets;
An optical disc apparatus characterized in that, when the optical disc is in an unrecorded state, trial writing is performed in a predetermined area of the optical disc by setting the first and second focus offsets before recording or joint recording. An optical disc apparatus that records and / or reproduces information on an optical disc,
An optical head that records or reads information by irradiating the optical disk with laser light;
The focus error is changed to obtain the maximum tracking error signal amplitude, the focus error detection circuit offset zero, the maximum signal amplitude of the RF signal based on the output of the optical head, and the minimum reproduction error signal. A first focus offset is set between the maximum signal amplitude and the focus error detection circuit offset, and a second focus is set between the maximum signal amplitude of the RF signal and the minimum reproduction error signal. A focus offset setting means for setting a third focus offset between the maximum signal amplitude of the RF signal and the focus error detection circuit offset zero;
An optical head control means for controlling the optical head based on the set first, second or third focus offset;
When the optical disc is in an unrecorded state, prior to recording or joint recording, trial writing is performed in a predetermined area of the optical disc with the first and second focus offset settings, and the optical disc is not in an unrecorded state. In some cases, the optical disc apparatus performs trial writing on a predetermined area of the optical disc by setting the second or third focus offset. First memory means for storing a first difference amount of the focus offset that maximizes the second focus offset and the tracking error amplitude; and a second difference amount of the focus offset that maximizes the tracking error amplitude. And a second memory means for obtaining a point at which a tracking error amplitude is maximized and a reproduction error signal is minimized by changing a focus offset in a previously recorded disk, and the first memory means and the second memory Means for recording the first difference amount and the second difference amount in the means, and when reproducing, recording, and joint recording on a disc different from the above, the first memory recorded in the first memory means The focus offset is changed to the difference amount, and the focus offset that maximizes the tracking error amplitude is added. A focus offset setting means for setting a fourth focus offset; and an optical head control means for controlling the optical head based on the set fourth focus offset. When the data recorded on the disc is reproduced by trial writing in the setting area, the focus offset is changed to the second difference amount recorded in the second memory means, and the maximum tracking error amplitude is set. A focus offset setting means for setting the fifth focus offset, and an optical head control means for controlling the optical head based on the set focus offset of the above-mentioned margin 5 to reproduce data. An optical disc according to claim 2 or claim 3, Apparatus. 5. The optical disk apparatus according to claim 4, wherein the first memory means and the second memory means are configured in a program in a microprocessor. A method for adjusting a focus offset of an optical disk apparatus that records or reproduces information on or from an optical disk,
Irradiating the optical disc with laser light;
Varying the focus offset to determine the maximum signal amplitude of the RF signal and the minimum reproduction error signal based on the output of the optical head;
Setting a focus offset between the maximum signal amplitude of the obtained RF signal and the minimum reproduction error signal;
Controlling the optical head based on the set focus offset;
Performing test writing on a predetermined area of the optical disc in the controlled optical head state;
And a focus offset adjustment method for adjusting the focus offset prior to the recording of information on the optical disc or the linkage recording. A method for adjusting a focus offset of an optical disk apparatus that records or reproduces information on or from an optical disk,
Irradiating the optical disc with laser light;
Changing the focus offset to obtain the maximum amplitude of the tracking error signal, the focus error detection circuit offset zero, the maximum of the signal amplitude of the RF signal, and the minimum of the reproduction error signal;
A first focus offset is set between the obtained maximum amplitude of the tracking error signal and the focus error detection circuit offset zero, and the maximum signal amplitude of the RF signal and the minimum reproduction error signal are set. In the meantime, setting a second focus offset;
Controlling the optical head based on the set first or second focus offset;
Performing test writing on a predetermined area of the optical disc with the controlled optical head;
Then, when the optical disc is in an unrecorded state, the focus offset is adjusted prior to recording or continuous recording. A focus offset adjustment program for an optical disk device that records or reproduces information on or from an optical disk,
To the microprocessor
A procedure for varying the focus offset to obtain the maximum signal amplitude of the RF signal and the minimum reproduction error signal;
A procedure for setting a focus offset between the maximum signal amplitude of the obtained RF signal and the minimum reproduction error signal;
A procedure for controlling the optical head based on the set focus offset;
A procedure for performing test writing on a predetermined area of the optical disc in the controlled optical head state;
The program for adjusting the focus offset of the optical disc apparatus is characterized in that the focus offset can be adjusted prior to the recording of information on the optical disc or the linkage recording.

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