JP4479583B2 - Optical disk device - Google Patents

Description

  The present invention relates to an optical disc apparatus, and more particularly to optimization of a recording strategy.

  When data is recorded on a recordable optical disk such as a DVD-R / + R disk, DVD-RW / + RW disk, or DVD-RAM, trial writing is performed in a test area provided on the inner circumference side of the optical disk, and a recording strategy is recorded. A technique for optimizing the above is known. Usually, in the development stage of an optical disc drive, a recording strategy is set for every optical disc provided on the market, stored in a nonvolatile memory in the optical disc drive, and an identification data ID of the optical disc is read and a corresponding recording strategy is set. The recording strategy can be optimized by reading from the memory. However, since there are optical discs in which the recording strategy is not stored in the memory, it is necessary to perform trial writing in the test area for such an optical disc to search for the optimum recording strategy.

  In the following patent document, as a recording strategy, paying attention to the pulse width of the first pulse, the pulse width of the subsequent pulse, and the recording power when recording data with multi-pulses, various combinations of these are changed and test writing is performed. And a technique for optimizing the pulse width of the leading pulse, the pulse width of the subsequent pulse, and the recording power is disclosed.

JP 2000-207742 A

  However, even if the recording strategy is optimized by focusing on the pulse width of the first pulse, the pulse width of the subsequent pulse, and the recording power as the recording strategy, it takes time to search for all combinations, and the test area It is necessary to secure a large area. Therefore, even if the recording strategy is limited to the pulse width of the first pulse, the pulse width of the subsequent pulse, and the recording power, a technique for searching for the optimum recording strategy more efficiently is desired.

  For optical disks that have been put on the market after the development of the optical disk drive, it may be possible to download firmware including the optimum recording strategy for the optical disk via the net and additionally store it in memory, but the download itself is complicated. There is a problem.

  An object of the present invention is to provide an apparatus capable of optimizing a recording strategy in a short time and with a small test area even for an arbitrary optical disk, particularly an optical disk in which an optimal recording strategy is not previously stored in a drive memory. is there.

The present invention is an optical disc apparatus for recording data with a recording strategy corresponding to an optical disc, wherein a leading pulse width Ttop and a succeeding pulse width Tmp in a plurality of parameters constituting the recording strategy are set to a predetermined Ttop and a predetermined Means for recording test data by changing the recording power as Tmp, and detecting the provisional optimum recording power by reproducing the test data; and fixing the Ttop and setting the Tmp within a predetermined range based on the predetermined Tmp The test data is recorded by changing the provisional optimum recording power so that the energy applied to the optical disc becomes the same, and the optimum subsequent pulse width is detected by reproducing the test data. means and the optimal succeeding pulse width was fixed, the Tt said predetermined Ttop as a basis for p is changed stepwise within a predetermined range, and the test data is recorded by changing the provisional optimum recording power so that the energy applied to the optical disk becomes the same, and the test data is reproduced to reproduce the optimum head. Means for detecting a pulse width; means for detecting the optimum recording power by fixing the optimum head pulse width and the optimum succeeding pulse width, changing the recording power, recording test data, and reproducing the test data; And means for recording data using the optimum head pulse width, the optimum subsequent pulse width and the optimum recording power as an optimum recording strategy.

Further, the present invention is an optical disc apparatus for recording data with a recording strategy corresponding to an optical disc, wherein a leading pulse width Ttop and a succeeding pulse width Tmp in a plurality of parameters constituting the recording strategy are respectively set to a predetermined Ttop and Means for recording test data by changing the recording power as a predetermined Tmp, and detecting the provisional optimum recording power by reproducing the test data; and fixing the Tmp and setting the Ttop with the predetermined Ttop as a reference By changing the provisional optimum recording power so that the energy irradiated to the optical disc is the same within a predetermined range and recording the test data, and reproducing the test data, the optimum leading pulse width is obtained. It means for detecting, the optimum top pulse width is fixed, before the predetermined Tmp based By changing Tmp stepwise within a predetermined range and changing the provisional optimum recording power so that the energy applied to the optical disc is the same, the test data is recorded, and the test data is reproduced to obtain the optimum succession. Means for detecting a pulse width, means for fixing the optimum head pulse width and the optimum succeeding pulse width, recording test data by changing recording power, and detecting optimum recording power by reproducing the test data And means for recording data using the optimum head pulse width, the optimum subsequent pulse width and the optimum recording power as the optimum recording strategy.

  According to the present invention, when recording test data with a combination of the leading pulse width and the succeeding pulse width, the process of optimizing by fixing one and changing the other is performed, and the irradiation energy in each combination is the same. Since the temporary optimum recording power is changed so as to be recorded, the optimum recording strategy can be searched efficiently and with high accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows an overall configuration diagram of an optical disc apparatus according to the present embodiment. An optical disk 10 such as a DVD-R or DVD-RW is rotationally driven by a spindle motor (SPM) 12. The spindle motor SPM 12 is driven by a driver 14, and the driver 14 is servo-controlled by a servo processor 30 so as to have a desired rotation speed.

  The optical pickup 16 includes a laser diode (LD) for irradiating the optical disk 10 with laser light and a photodetector (PD) that receives reflected light from the optical disk 10 and converts it into an electrical signal, and is disposed opposite to the optical disk 10. . The optical pickup 16 is driven in the radial direction of the optical disk 10 by a thread motor 18, and the thread motor 18 is driven by a driver 20. The driver 20 is servo-controlled by the servo processor 30 similarly to the driver 14. The LD of the optical pickup 16 is driven by a driver 22, and the driver 22 is controlled by an auto power control circuit (APC) 24 so that the drive current becomes a desired value. The APC 24 controls the drive current of the driver 22 so that the optimum recording power selected by OPC (Optimum Power Control) executed in the test area (PCA) of the optical disc 10 is obtained. The OPC is a process of recording test data on the PCA of the optical disc 10 by changing the recording power in a plurality of stages, reproducing the test data, evaluating the signal quality, and selecting a recording power that can obtain a desired signal quality. It is. For the signal quality, β value, γ value, modulation factor, jitter, etc. are used.

  When data recorded on the optical disk 10 is reproduced, a laser beam of reproduction power is irradiated from the LD of the optical pickup 16, and the reflected light is converted into an electric signal by the PD and output. A reproduction signal from the optical pickup 16 is supplied to the RF circuit 26. The RF circuit 26 generates a focus error signal and a tracking error signal from the reproduction signal and supplies them to the servo processor 30. The servo processor 30 servo-controls the optical pickup 16 based on these error signals, and maintains the optical pickup 16 in an on-focus state and an on-track state. Further, the RF circuit 26 supplies the reproduction signal to the address decoding circuit 28.

  The address decoding circuit 28 demodulates the address data from the reproduction signal and supplies it to the servo processor 30 and the system controller 32.

  Further, the RF circuit 26 supplies the reproduction RF signal to the binarization circuit 34. The binarization circuit 34 binarizes the reproduction signal and supplies the obtained modulation signal to the encoding / decoding circuit 36. The encode / decode circuit 36 demodulates the binary signal and corrects an error to obtain reproduction data, and outputs the reproduction data to a host device such as a personal computer via the interface I / F 40. When the reproduction data is output to the host device, the encoding / decoding circuit 36 temporarily stores the reproduction data in the buffer memory 38 and outputs it.

  When recording data on the optical disk 10, data to be recorded from the host device is supplied to the encode / decode circuit 36 via the interface I / F 40. The encode / decode circuit 36 stores data to be recorded in the buffer memory 38, encodes the data to be recorded, and supplies the data to the write strategy circuit 42. The write strategy circuit 42 converts the modulation data into a multi-pulse (pulse train) according to a predetermined recording strategy, and supplies it to the driver 22 as recording data. Although there are a plurality of parameters that define the recording strategy, the present embodiment uses the pulse width of the first pulse, the pulse width of the subsequent pulse, and the recording power in the multi-pulse as in the above-described conventional technique. The recording strategy is set during OPC. When the recording strategy corresponding to the optical disc 10 is stored in advance in the nonvolatile memory of the system controller 32, the recording strategy is set as the optimum recording strategy. When the corresponding recording strategy does not exist in the memory, The system controller 32 searches for an optimum recording strategy by optimizing the leading pulse width and the like during OPC. The laser light whose power is modulated by the recording data is irradiated from the LD of the optical pickup 16 and the data is recorded on the optical disk 10. Data recording is in units of packets. After recording the data in packet units, the optical pickup 16 reproduces the recorded data by irradiating the laser beam with the reproduction power, and supplies it to the RF circuit 26. The RF circuit 26 supplies the reproduction signal to the binarization circuit 34, and the binarized modulation data is supplied to the encode / decode circuit 36. The encode / decode circuit 36 decodes the modulated data and collates it with recorded data stored in the buffer memory 38. The result of the verification is supplied to the system controller 32.

  FIG. 2 and FIG. 3 show parameters to be noted in the recording strategy. FIG. 2 shows a recording strategy corresponding to a data length 3T (T is a reference data length), and FIG. 3 shows a recording strategy corresponding to a data length 6T. Focusing on the pulse width Ttop of the first pulse, the pulse width Tmp of the subsequent pulse, and the recording power P as the recording strategy, these three parameters are optimized according to the optical disc. In FIG. 2, the data length 3T is recorded by only the head pulse, and the data length 6T is recorded by the head pulse and a plurality of subsequent pulses. In addition to these three parameters, the recording strategy includes the leading edge rising timing depending on the space length. The applicant of the present application, among the plurality of parameters constituting the recording strategy, has the leading pulse width and the trailing pulse. Experiments have confirmed that reproducible data recording can be performed by adjusting three parameters of width and recording power. Hereinafter, a method for optimizing these three parameters in the present embodiment will be described.

First, for every possible optical disc, the possible range of the leading pulse width and the range of the subsequent pulse width are equally divided, for example, into five equal parts. Specifically, the range of the first pulse width is 1.500T to 1.700T, the range of the subsequent pulse width is 0.600T to 0.700T, and each range is divided into five equal parts.
First pulse width:
1.500T, 1.550T, 1.600T, 1.650T, 1.700T
Subsequent pulse width:
0.600T, 0.625T, 0.650T, 0.675T, 0.700T
It is. The range of the pulse width defined in the DVD standard may be used as it is.

  FIG. 4 shows combinations of values that can be taken by the leading pulse width and the succeeding pulse width in a tabular form. A total of 25 combinations of the first pulse width 5 samples and the subsequent pulse width 5 samples are obtained. In FIG. 4, each combination is shown as “condition i” (i is 1 to 25). For example, “condition 13” is a condition with a leading pulse width of 1.600 T and a trailing pulse width of 0.650 T.

  After setting a plurality of conditions, an arbitrary condition of the conditions i is set as a start condition, and the optimum recording power under the conditions is searched. For example, the condition 13 which is the central condition among the conditions 1 to 25 is set as the start condition, and the recording power is changed stepwise by the head pulse width and the subsequent pulse width specified by the condition 13 to test the optical disc 10. Test data is recorded in the area, and a reproduction signal quality obtained by reproducing the test data, for example, a β value is evaluated to search for an optimum recording power in the condition 13. Note that the optimum recording power searched in this way is only the optimum recording power under the condition 13, and is not necessarily guaranteed to be the optimum recording power in the optimum recording strategy. ". After searching for the provisional optimum recording power under the condition 13, the process proceeds to the optimum search algorithm for the first pulse width and the subsequent pulse width.

  The optimum search algorithm for the head pulse width and the subsequent pulse width is composed of the following two steps. The first step is to search for the optimum subsequent pulse width by changing the succeeding pulse width while fixing the leading pulse width, and the second is to fix the succeeding pulse width to the optimum succeeding pulse width and changing the leading pulse width. In this step, the optimum head pulse width is searched. In FIG. 4, the first step starts from condition 13 and changes in the horizontal direction, that is, conditions 11, 12, 12, and 15 to search for the optimum value of the subsequent pulse width. The step is a step of searching for the optimum head pulse width by changing the conditions in the vertical direction.

  Here, when the conditions are changed, the provisional optimum recording power is also changed at the same time. This is because when the value of the head pulse width or the subsequent pulse width changes, the energy irradiated to the optical disk changes if the irradiation power is kept at a fixed value, and the change in the reproduction signal quality obtained by reproducing the test data is This is because it cannot be identified whether it is caused by changing the conditions or if it is caused by changing the irradiation energy. In the present embodiment, in view of such circumstances, the energy applied to the optical disc is kept the same between the conditions by changing the conditions and changing the recording power applied to the optical disc. Specifically, since the irradiation energy is determined by recording power × irradiation time, when changing from one condition to another, it is only necessary to change the recording power so as to compensate for the time change accompanying the change in the condition. . The change in recording power will be further described later.

  FIG. 5 shows the first step, that is, the subsequent pulse width optimization process (Tmp determination flow). The system controller 32 sets the condition 13 as a start condition, and changes the recording power stepwise in the test area of the optical disc 10 at a start pulse width of 1.600 T and a subsequent pulse width of 0.650 T specified by the condition 13 for recording. The test data is reproduced to calculate the β value for each recording power. The β value for each recording power is compared with the target β value stored in advance in the memory, and the recording power at which the β value closest to the target β value is obtained is set as the provisional optimum recording power.

  After detecting the provisional optimum recording power in the condition 13, the test data is recorded again for one ECC block with the condition 13 and the provisional optimum recording power, and the jitter is measured by reproducing the test data. The jitter amount obtained by recording the test data with the condition 13 and the provisional optimum recording power is “13J”. The recorded test data may be reproduced when the provisional optimum recording power is detected, and the jitter amount may be measured. Thereby, the test data re-recording process with the condition 13 and the temporary optimum recording power can be omitted.

  After measuring the jitter amount “13J” under the condition 13 and the provisional optimum recording power, next, test data is recorded for one ECC block with the head pulse width and the subsequent pulse width specified by the condition 12. The leading pulse width of condition 12 is the same as the leading pulse width of condition 13. When changing the subsequent pulse width, the recording power is not the temporary optimum recording power, but test data is recorded by changing the temporary optimum recording power so that the irradiation energy in the condition 12 is the same as the irradiation energy in the condition 13. Test data is recorded with the condition 12 and the temporary optimum recording power after the change, and the amount of jitter obtained by reproducing the test data is measured. The obtained jitter amount is set to “12J”.

  Next, test data is recorded with the head pulse width and the subsequent pulse width defined by the condition 14. Also in this case, the recording power is not the temporary optimum recording power, but the temporary optimum recording power is changed so that the irradiation energy in the condition 14 and the irradiation energy in the condition 13 are the same. Test data is recorded with the condition 14 and the temporary optimum recording power after the change, and the jitter is measured by reproducing the test data. The obtained jitter amount is set to “14J”. After measuring the jitter amounts 12J, 13J, and 14J of the conditions 12 and 14 adjacent to the conditions 13 and 13, the magnitudes of these three jitter amounts are compared. When 13J is the smallest among 12J, 13J, and 14J, or when these three jitter amounts are substantially equal, the condition 13 that is the start condition is assumed to be the optimum condition, and the subsequent conditions defined by the condition 13 The pulse 0.650T is the optimum subsequent pulse. On the other hand, when 12J is the smallest among 12J, 13J, and 14J, it means that an optimum value may exist in the direction of condition 12 when viewed from condition 13 in FIG. Test data is recorded with the first pulse width and the subsequent pulse width. Even in this case, the provisional optimum recording power is changed so that the irradiation energy in the condition 11 and the irradiation energy in the condition 13 are the same. The test data is recorded with the condition 11 and the provisional optimum recording power after the change, and the jitter amount obtained by reproducing the test data is “11J”. After measuring the jitter amount 11J under condition 11, 11J and 12J are compared in size. If 11J is smaller than 12J as a result of the size comparison, the subsequent pulse width 0.600T defined by condition 11 is set as the optimum subsequent pulse width. On the other hand, when 11J is 12J or more, the subsequent pulse width 0.625T defined by the condition 12 is set as the optimum subsequent pulse width. In addition, when 14J is the smallest among 12J, 13J, and 14J, it means that there is an optimum value in the direction of condition 14 when viewed from condition 13, and therefore, the leading pulse width and the following that are defined in condition 15 Record test data with pulse width. Also in this case, the provisional optimum recording power is changed so that the irradiation energy of the condition 15 and the irradiation energy of the condition 13 are the same. It is assumed that the jitter amount obtained by recording the test data with the condition 15 and the temporary optimum recording power after the change and reproducing the test data is 15 J ”. After measuring the jitter amount 15J under the condition 15, 14J and 15J are compared in size. When 15J is smaller than 14J, the subsequent pulse width 0.700T defined by the condition 15 is set as the optimum subsequent pulse width. When 15J is 14J or more, the subsequent pulse width 0.675T defined by the condition 14 is set as the optimum subsequent pulse width. With the above processing, the optimization of the subsequent pulse width is completed. The subsequent pulse width can be optimized by recording test data up to four times.

  FIG. 6 shows the second step, that is, the head pulse width optimization process (Ttop determination flow). The head pulse width optimization process is the same as the subsequent pulse width optimization process described above. Test data is recorded under adjacent conditions centered on the condition of the subsequent pulse width optimized in the subsequent pulse width optimization process, and the jitter Measure the amount and compare the amount of jitter to determine the direction of the optimization search. FIG. 6 shows a process when the condition 15 is determined as the optimum condition of the subsequent pulse width in the process of FIG. First, test data is recorded with the head pulse width and the subsequent pulse width specified by the condition 10 adjacent to the condition 15, and the jitter amount obtained by reproducing the test data is set to “10J”. The subsequent pulse width of condition 10 is the same as the subsequent pulse width of condition 15, and the leading pulse width is different. Needless to say, when changing the leading pulse width, the provisional optimum recording power is changed so that the irradiation energy becomes the same. Next, test data is recorded with the head pulse width and the subsequent pulse width specified by the condition 20, and the jitter amount obtained by reproducing the test data is set to “20J”. After obtaining three jitter amounts, 10J, 15J, and 20J, the magnitude comparison of 10J, 15J, and 20J is performed. When 15J is the smallest among 10J, 15J, and 20J, the head pulse width 1.600T defined by the condition 15 is set as the optimum head pulse width. On the other hand, when 10J is the smallest among 10J, 15J, and 20J, the test data is further recorded with the head pulse width and the subsequent pulse width specified by the condition 5, and the jitter amount “5J” obtained by reproducing the test data is recorded. Is compared with 10J. Of the condition 5 and the condition 10, the head pulse width under the condition that a smaller jitter amount is obtained is set as the optimum head pulse width. Further, when 20J is the smallest among 10J, 15J, and 20J, the test data is further recorded with the head pulse width and the subsequent pulse width specified by the condition 25, and the jitter amount “25J” obtained by reproducing the test data is recorded. "Is compared with 20J in size. Of the conditions 20 and 25, the head pulse width under the condition that a smaller jitter amount is obtained is set as the optimum head pulse width. With the above processing, the leading pulse width is optimized. The head pulse width optimization process can be performed up to three times of test data recording. Eventually, the head pulse width and the subsequent pulse width are both optimized by a maximum of seven test data recordings.

  After searching for the optimum head pulse width and the optimum subsequent pulse width, the true optimum recording power is searched for next. That is, the test data is recorded by changing the recording power stepwise with the optimum head pulse width and the optimum subsequent pulse width, and the recording power that minimizes the jitter amount of the test data is set as the true optimum recording power. Note that the true optimum recording power is set so that the irradiation energy under the condition defined by the optimum head pulse width and the optimum subsequent pulse width (for example, condition 15) is the same as the irradiation energy under the condition 13 and the provisional optimum recording power. Although it is possible to calculate, since there is no guarantee that the start condition condition 13 is the optimum condition, the temporary optimum recording power is not changed or corrected, but the recording power is optimized again under the optimum condition. Is preferred.

  In this way, the head pulse width, the subsequent pulse width, and the recording power are optimized in a short time and with a small number of test data recording times, and the optimum recording strategy of the optical disc 10 is set.

  Hereinafter, a method for changing the provisional optimum recording power when recording test data under different conditions will be described. Irradiation energy is calculated as irradiation energy = irradiation recording power × time. In addition to the target of all data lengths as irradiation time, the appearance frequency (ratio) such as 3T to 5T or 3T to 6T is a predetermined value or more. It is efficient to use only the irradiation time of the data length that is high and appears frequently in the data. In the present embodiment, the irradiation energy is calculated using an integrated irradiation time with a data length of 3T to 6T.

FIG. 7 shows the irradiation time of the data length 3T to 6T, that is, the integration of the head pulse width and the subsequent pulse width for each condition shown in FIG. For example, in condition 13, the irradiation time (μs) for the data length 3T is 1.6, the irradiation time for the data length 4T is 2.25, the irradiation time for the data length 5T is 3.55, and the irradiation time for the data length 6T is 5 Therefore, the integrated irradiation time of the data length 3T to 6T is 12.9 of these totals. Under condition 12, the irradiation time for data length 3T is 1.6, the irradiation time for data length 4T is 2.225, the irradiation time for data length 5T is 3.475, and the irradiation time for data length 6T is 5.35. Therefore, the total irradiation time of the data length 3T to 6T is 12.65 of the total of these. Therefore, when the test data is recorded with the head pulse width and the subsequent pulse width specified in the condition 12, the temporary optimum recording power T0 in the condition 13 is
P1 = P0 × 12.9 / 12.65
The recording power P1 may be changed.

Similarly, when recording test data under condition 11,
P1 = P0 × 12.9 / 12.4
The recording power P1 may be changed. The system controller 32 stores the accumulated irradiation time of data length 3T to 6T corresponding to each condition shown in FIG. 7 in the memory.

  In this way, by changing the irradiation recording power under each condition so that the irradiation energy of a specific data length is the same, the leading pulse width and the subsequent pulse width can be optimized efficiently.

  As mentioned above, although embodiment of this invention was described, this invention is not restricted to this, A various change is possible.

  For example, in this embodiment, the jitter amount is used as the reproduction signal quality of the test data under each condition, but the evaluation may be performed using an error rate.

  Further, in the present embodiment, the condition 13 is the start condition, but the process can be started from an arbitrary condition. The applicant of the present application has confirmed that almost all optical discs can be covered under the conditions 1 to 25 shown in FIG. In addition, among the conditions 1 to 25 shown in FIG. 4, an optical disk of a certain type (manufacturer) concentrates particularly in the vicinity of conditions 1, 2, 3, 6, 7, 8 and another type (manufacturer) In particular, it has been confirmed that optimum conditions are concentrated in the vicinity of conditions 18, 19, 20, 23, 24, and 25 for optical disks. Therefore, the type of the optical disk may be detected, and the condition to be searched for among the conditions 1 to 25 may be further limited according to the type.

  In this embodiment, the subsequent pulse width is first optimized and then the head pulse width is optimized. However, the subsequent pulse width may be optimized after the head pulse width is optimized.

  Furthermore, in the present embodiment, the temporary optimum recording power is changed using 3T to 6T as the data length that appears at a frequency (ratio) greater than or equal to a predetermined value, but 3T to 4T may be used, and 3T may be multi-valued. When recording with pulses, it is possible to use only 3T.

1 is a block diagram illustrating a configuration of an optical disc device. It is explanatory drawing of a recording strategy of recording data length 3T. It is explanatory drawing of a recording strategy of recording data length 6T. It is combination explanatory drawing of a start pulse width and a succeeding pulse width. It is explanatory drawing which shows the optimization algorithm of a subsequent pulse width. It is explanatory drawing which shows the optimization algorithm of a head pulse width. It is explanatory drawing which shows the change method of temporary optimal recording power.

Explanation of symbols

  10 optical disk device, 16 pickup, 32 system controller, 42 write strategy circuit.

Claims (4)

An optical disk device for recording data with a recording strategy corresponding to an optical disk,
Recording test data by changing the recording power with the first pulse width Ttop and the subsequent pulse width Tmp being a predetermined Ttop and a predetermined Tmp, respectively, among a plurality of parameters constituting the recording strategy, and reproducing the test data Means for detecting the provisional optimum recording power at
The Ttop is fixed, the Tmp is changed stepwise within a predetermined range with the predetermined Tmp as a reference, and the provisional optimum recording power is changed so that the energy irradiated onto the optical disc becomes the same. Means for detecting the optimum subsequent pulse width by reproducing the test data;
The optimum optimum pulse width is fixed, the Ttop is changed stepwise within a predetermined range on the basis of the predetermined Ttop, and the provisional optimum recording power is changed so that the energy irradiated to the optical disc becomes the same. Means for recording the test data and reproducing the test data to detect the optimum head pulse width;
Means for fixing the optimum head pulse width and the optimum subsequent pulse width, changing the recording power to record test data, and reproducing the test data to detect the optimum recording power;
Means for recording data using the optimum head pulse width, the optimum subsequent pulse width and the optimum recording power as an optimum recording strategy;
An optical disc apparatus comprising: An optical disk device for recording data with a recording strategy corresponding to an optical disk,
Recording test data by changing the recording power with the first pulse width Ttop and the subsequent pulse width Tmp being a predetermined Ttop and a predetermined Tmp, respectively, among a plurality of parameters constituting the recording strategy, and reproducing the test data Means for detecting the provisional optimum recording power at
The Tmp is fixed, the Ttop is changed stepwise within a predetermined range with the predetermined Ttop as a reference, and the temporary optimum recording power is changed so that the energy applied to the optical disc is the same, and the test data Means for detecting the optimum head pulse width by reproducing the test data;
The optimum head pulse width is fixed, the Tmp is changed stepwise within a predetermined range with the predetermined Tmp as a reference, and the provisional optimum recording power is changed so that the energy applied to the optical disc is the same. Means for recording the test data and detecting the optimum subsequent pulse width by reproducing the test data;
Means for fixing the optimum head pulse width and the optimum subsequent pulse width, changing the recording power to record test data, and reproducing the test data to detect the optimum recording power;
Means for recording data using the optimum head pulse width, the optimum subsequent pulse width and the optimum recording power as an optimum recording strategy;
An optical disc apparatus comprising: The apparatus according to claim 1,
An optical disc apparatus, wherein the provisional optimum recording power is changed so that irradiation energy of a recording data length having an appearance frequency equal to or greater than a predetermined value is the same. The apparatus of claim 3.
An optical disc apparatus characterized in that the provisional optimum recording power is changed so that irradiation energy of a recording data length equal to or less than 6T (T is a reference data length) is the same.

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