JP4565340B2 - Write strategy setting method, write strategy setting device, recording medium driving device, and pickup module - Google Patents

Description

The present invention, the write strategy setting method, the write strategy setting device, relates to a recording medium drive and the pickup module, and more particularly, is suitably applied to an optical disc drive of the recording and reproducing type.

  Conventionally, an optical disk drive irradiates a recording film of an optical disk as a recording medium with laser light, forms a recording mark having a mark length defined by a standard on the recording film, and records data on the optical disk. As shown in FIG. 7, this optical disc drive has a write strategy that defines the control timing of the laser beam, and generates a timing control signal from an EFM (Eight to Fourteen Modulation) signal based on this write strategy. Thus, the laser beam is precisely controlled so as to raise the recording film of the optical disk to a predetermined temperature.

  As this write strategy, for example, a multi-pulse recording method in which laser light is divided and irradiated in a pulse shape, a block recording method in which laser light is divided and irradiated in a block shape, and both before and after the pulse by controlling both power and time axis Various methods are known, such as a castle style method in which power is increased at the end to irradiate in a castle shape, and the method is appropriately selected according to various recording conditions such as the type of optical disk and the recording speed of the optical disk drive.

  On the other hand, since the recording characteristics of the optical disc vary depending on the manufacturer, etc., if the recording mark is uniformly formed using one write strategy, the mark length of the recording mark formed on the recording film varies. Will occur. For this reason, it is required to increase the accuracy of the recording mark by adjusting the write strategy according to the characteristics of the optical disk.

For this reason, the recording mark is test-recorded in accordance with a pre-stored write strategy, and the reproduction RF signal reproduced from the test recorded recording mark is compared with a preset setting reproduction RF signal. An optical disc drive that optimizes the write strategy has been proposed (see, for example, Patent Document 1).
JP2003-271630

  By the way, in the optical disk drive having such a configuration, recording marks having 10 mark lengths (hereinafter referred to as standard mark lengths) of 3T to 10T, 11T, and 14T defined in the standard corresponding to the optical disk are formed. Hereinafter, a mark having a standard mark length n is referred to as an nT mark (3T mark to 14T mark), and is simply referred to as a mark when the standard mark length is not particularly limited.

  The reproduction RF signal read from this mark shows a waveform as shown in FIG. At this time, the peak of the reproduction RF signal corresponding to the smallest 3T mark is smaller than the waveform of the reproduction RF signal corresponding to the 4T mark, and therefore, as shown in FIG. The slope near ZL is gentle.

  That is, when the waveform of the reproduction RF signal is shifted downward with respect to the zero level ZL due to noise due to disturbance, intersymbol interference, etc., and changes to a positional relationship such as the zero level ZL ′ indicated by a broken line, the 4T mark Compared with the shift amount SH4 in the time axis direction when the zero-cross point ZC4 of the reproduction RF signal according to the shift to the zero-cross point ZC4 ′, the zero-cross point ZC3 of the reproduction RF signal according to the 3T mark is the zero-cross point ZC3 ′. There is a problem that the shift amount SH3 in the direction of the time axis in the case of shifting to is large, and the quality of the reproduction RF signal is greatly deteriorated.

The present invention has been made in view of the foregoing, it is intended to propose write strategy setting method of improving the quality of the reproduced RF signal, a write strategy setting device, the recording medium drive and the pickup module.

In order to solve this problem, the write strategy setting method of the present invention includes a recording step of forming a predetermined recording mark on an optical disc by irradiating the optical disc with laser light based on the initial write strategy, and an optical disc. A reproduction step for reading out the recording mark formed by the reproducing means and generating a reproduction signal corresponding to the recording mark, and an actual mark length of the recording mark based on the reproduction signal and a standard mark length defined by a predetermined standard In accordance with the difference , a correction step for correcting the initial write strategy by the correcting means so that the actual mark length matches the standard mark length, and a correction write strategy obtained as a result of correcting the optical disc by the correction step setting means as the set write strategy for the optical disc Comprising a setting step to further set, in the correction step, of the recording marks, the minimum actual mark length of the recording mark having a standard mark length, the initial write strategy to be longer by a predetermined additional length than standard mark length I corrected it.

As a result, when the initial write strategy is corrected so that the actual mark length matches the standard mark length, the actual mark length of the recording mark having the minimum standard mark length is longer than the standard mark length by a predetermined additional length. since the initial write strategy can be corrected as, steeply to noise immunity than prior deskew a zero level near the No. re Namashin can be improved.

Further, the write strategy setting device, the recording medium driving device, and the pickup module of the present invention include a recording unit that forms a predetermined recording mark on the optical disc by irradiating the optical disc with laser light based on the initial write strategy, A reproduction means for reading a recording mark formed on an optical disc and generating a reproduction signal corresponding to the recording mark, and a difference between an actual mark length of the recording mark based on the reproduction signal and a standard mark length defined by a predetermined standard Accordingly , a correction unit that corrects the initial write strategy so that the actual mark length and the standard mark length match, and a correction write strategy that is obtained as a result of correction by the correction unit is set for the optical disc. comprising a setting means for setting a write strategy correction means, the recording Of over click, the actual mark length of recording marks having a minimum standard mark length and to correct the initial write strategy to be longer by a predetermined additional length than standard mark length.

As a result, when the initial write strategy is corrected so that the actual mark length matches the standard mark length, the actual mark length of the recording mark having the minimum standard mark length is longer than the standard mark length by a predetermined additional length. since the initial write strategy can be corrected as, steeply to noise immunity than prior deskew a zero level near the No. re Namashin can be improved.

According to the present invention, when the initial write strategy is corrected so that the actual mark length matches the standard mark length, the actual mark length of the recording mark having the minimum standard mark length is a predetermined additional length than the standard mark length. Since the initial write strategy can be corrected so that it becomes longer, the slope near the zero level in the playback signal can be steeper than before correction to improve noise resistance, thus improving the quality of the playback signal. strategy setting method, the write strategy setting device, the recording medium drive and the pickup module can be realized.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

(1) Overall Configuration of Optical Disk Drive In FIG. 1, reference numeral 1 denotes an optical disk drive as a whole. In this optical disk drive 1, a CPU (Central Processing Unit) 3 of the control IC 2 controls each part of the optical disk drive 1. The CPU 3 executes various processes such as a writing process and a write strategy setting process (to be described later) based on various basic programs and a write strategy setting program stored in advance in a storage unit 4 such as a RAM (Random Access Memory). To do. The storage unit 4 stores a write strategy used in the writing process, calibration data used in the write strategy setting process, and the theoretical signal length MT.

  The CPU 3 rotates the spindle motor 6 via the servo circuit 5 and rotationally drives the optical disk 20 placed on a turntable (not shown). Further, the CPU 3 rotates the sled motor 7 via the servo circuit 5 to move the optical pickup 8 in the tracking direction of the optical disc 20. Further, the CPU 3 controls the biaxial actuator 8E of the optical pickup 8 to drive the objective lens 8C of the optical pickup 8 in the tracking direction and the focus direction.

  The optical pickup 8 emits a light beam from the laser diode 8B, and irradiates the optical disk 20 with the light beam via the objective lens 8C. When the optical pickup 8 receives the reflected light beam formed by reflecting the light beam by the optical disc 20 by the photodetector 8D, the optical pickup 8 photoelectrically converts the received reflected light beam into an electrical signal corresponding to the amount of reflected light. The signal is sent to the signal processing unit 9.

  In the reading process, the write strategy generation unit 10 generates a control signal for controlling the laser power, thereby reading the data recorded on the optical disc 20 while controlling the laser diode 8B via the laser driver 8A.

  Further, in the writing process, the write strategy generation unit 10 performs light based on the write strategy (initial write strategy, correction write strategy, and set write strategy) that defines the control conditions of the laser diode 8B stored in the storage unit 4. A timing control signal for controlling the irradiation timing and laser power of the laser diode 8B of the pickup 8 is generated, and the laser diode 8B is driven and controlled via the laser driver 8A based on the timing control signal, thereby writing data on the optical disc 20. It is made like that.

  Incidentally, the optical disc drive 1 forms recording marks having ten standard mark lengths defined in the standard corresponding to the optical disc 20. Hereinafter, a recording mark having a standard mark length n is referred to as an nT mark (3T mark to 14T mark), and is simply referred to as a mark when the standard mark length is not particularly limited.

(2) Write strategy setting process Next, a write strategy setting process used in the above-described writing process will be described.

  The optical disc drive 1 is an optical disc 20 such as a DVD-R (Digital Versatile Disc-Recordable) or a DVD + R based on an initial write strategy (hereinafter referred to as an initial write strategy) stored in the storage unit 4 in advance. Correction write strategies (first to third correction write strategies) corresponding to the characteristics of the optical disk 20 based on the type of the optical disk 20 and the manufacturer of the optical disk 20 or the like are generated. It is designed to set a write strategy.

  When the CPU 3 of the optical disk drive 1 recognizes that the user has requested to set the write strategy by operating the operation unit (not shown), the objective lens 8C of the optical pickup 8 is connected to the PCA (Power Move to the Calibration Area area. Then, the CPU 3 reads out the calibration data stored in the storage unit 4 in advance, and generates an EFM (Eight to Fourteen Modulation) signal based on the calibration data.

  Here, the initial write strategy is stored in the storage unit 4 in advance. In this initial write strategy, control conditions for generating three timing control signals for controlling the laser diode 8B from the EFM signal are defined.

  As shown in FIG. 2, when the CPU 3 reads this initial write strategy from the storage unit 4, the CPU 3 sets the initial write strategy in the write strategy generation unit 10. The write strategy generation unit 10 generates three timing control signals (a write timing signal WT, an overdrive timing signal OT, and a cooling timing signal CT) based on the EFM signal and the initial write strategy, and sends them to the laser driver 8A. To do.

  The write timing signal WT indicates the timing for controlling the laser power of the light beam 30A to the mark forming write power WP, the over timing signal OT indicates the timing for controlling the overdrive power OP with the largest laser power, The cooling timing signal CT represents the timing for controlling the cooling power CP for cooling with the smallest laser power. Note that when the write timing signal WT and the over timing signal OT fall and the cooling timing signal CT rises, the read power RP is controlled.

  The laser driver 8A generates a drive current for the laser diode 8B according to these timing control signals so as to obtain four levels of current values of write power WP, overdrive power OP, cooling power CP, and read power RP.

  The laser driver 8A drives the laser diode 8B according to this drive current, thereby irradiating the laser diode 8B with a light beam with a light emission waveform as shown in FIG. Record in the area.

  Next, the CPU 3 executes the above-described calibration mark reading process. At this time, the write strategy generation unit 10 emits a light beam from the laser diode 8B in a state where the laser power is the read power RP. As a result, the signal processing unit 9 generates a reproduction RF signal from the electrical signal corresponding to the reflected light beam reflected by the optical disc 20 supplied from the photodiode 8D.

  The signal processing unit 9 generates a binarized reproduction signal from the reproduction RF signal, and the write strategy generation unit 10 measures the length of the portion corresponding to the mark (3T to 14T mark) in the binarized reproduction signal. This is the actual signal length MR representing the actual length of the mark.

  Further, the CPU 3 reads the theoretical signal length MT representing the length of the binarized reproduction signal when each mark is recorded on the optical disc 20 according to the standard mark length, and sends it to the write strategy generation unit 10.

  When the actual signal length MR and the theoretical signal length MT are supplied, the write strategy generation unit 10 based on the difference between the actual signal length MR and the theoretical signal length MT, makes the initial write strategy so that they match. Is corrected to generate a first corrected write strategy.

  Next, the CPU 3 re-records a calibration mark on the optical disc 20 based on the first correction write strategy by the same process as in the initial write strategy, and performs the second correction based on the reproduction RF signal corresponding to the mark. When the write strategy is generated, the same process is repeated once more based on the second corrected write strategy to generate the third corrected write strategy.

  As a result, the CPU 3 repeats a loop for generating a new corrected write strategy using a write strategy corresponding to the characteristics of the optical disc 20 by a predetermined number of repetitions (for example, three times), thereby generating the newly generated corrected write strategy. Since the result can be fed back to the corrected write strategy to be generated next, the characteristics of the optical disc 20 are reflected in the finally generated third corrected write strategy so that a highly accurate mark can be recorded on the optical disc 20. Has been made.

  Then, the CPU 3 stores the third correction write strategy and the set write strategy corresponding to the optical disc 20 by storing the third correction write strategy in correspondence with the ID information unique to each optical disc 20 in the storage unit 4. Has been made to set as.

  Here, as described above with reference to FIG. 8B, the waveform of the reproduction RF signal corresponding to the shortest 3T mark has a problem that the slope near the zero level ZL is gentle and noise resistance is low. .

  Therefore, even if the 3T mark can be formed accurately, the waveform of the reproduction RF signal corresponding to the 3T mark still has the problem that the noise resistance is low.

  For this reason, in the optical disc drive 1 of the present invention, the 3T mark is recorded so that the actual mark length of the 3T mark (hereinafter referred to as the actual mark length) is longer than 3T by T / 16. The noise resistance of the reproduction RF signal corresponding to the 3T mark can be improved.

  That is, as shown in FIG. 7, the conventional optical disk drive records 3T to 14T marks so that the actual mark length is 1T × n (n = 3 to 14) with 1T as a unit. In the optical disc drive 1 of the invention, as shown in FIG. 4, the 4T to 14T marks are recorded so that the actual mark length is 1T × n (n = 4 to 14) as in the prior art, while the 3T marks are actually recorded. Recording is performed so that the mark length is 3T + T / 16.

  Specifically, the CPU 3 sets the theoretical signal length MT for the 4T mark to 14T mark to the length of the binarized reproduction signal generated when the mark is recorded with the actual mark length 4T, 5T,. And the theoretical signal length MT for the 3T mark described above is set to the length of the binarized reproduction signal generated when the mark is recorded with the actual mark length 3T + T / 16.

  As a result, as shown in FIG. 5A, the actual mark length in the 3T mark is longer by T / 16 than 3T, and the peak portion in the reproduction RF signal corresponding to the 3T mark is increased by this T / 16. Therefore, as shown in FIG. 5B, the slope of the reproduction RF signal near the zero level ZL can be made steep, and the time axis of the zero cross point ZC3 when the reproduction RF signal is shifted in the vertical direction. Since the shift amount in the direction can be reduced, jitter in the reproduction RF signal can be reduced, and noise tolerance in the reproduction RF signal corresponding to the 3T mark can be improved.

(3) Write Strategy Generation Processing Procedure Next, the write strategy generation processing procedure executed based on the write strategy generation program will be described with reference to the flowchart of FIG.

  When the CPU 3 of the optical disc drive 1 makes a request to generate a write strategy from the user, the CPU 3 enters from the start step of the write strategy setting processing procedure RT1 and proceeds to the next step SP1.

  In step SP1, the CPU 3 records calibration data on the optical disc 20 by recording calibration data on the optical disc 20 based on the initial write strategy.

  In step SP2, the CPU 3 reproduces the calibration data recorded in step SP1, thereby generating a binarized reproduction signal corresponding to the calibration mark.

  In step SP3, the CPU 3 generates a correction write strategy so that both coincide with each other based on the difference between the actual signal length MR (FIG. 3) and the theoretical signal length MT in the binarized reproduction signal generated in step SP2. Then, the process proceeds to the next step SP4.

  At this time, the CPU 3 corrects the actual mark length so that the actual mark length becomes 3T + T / 16 for the 3T mark and the actual mark length becomes 4T to 14T for the standard mark lengths 4T to 14T by setting the theoretical signal length MT. Generate a write strategy.

  In the next step SP4, the CPU 3 determines whether or not the corrected write strategy has been generated three times, which is a predetermined number of times.

  If a negative result is obtained here, the CPU 3 returns to the next step SP1 at this time, re-forms a calibration mark based on the latest correction write strategy generated in step SP3, and determines the correction write strategy. Continue the generation process.

  On the other hand, if an affirmative result is obtained in step SP4, this means that the third corrected write strategy in which the characteristics of the optical disk 20 are sufficiently fed back has been generated. Then, the process proceeds to the next step SP5, and when the third corrected write strategy is set as the set write strategy for the optical disc 20, the process is terminated.

(4) Operation and Effect In the above configuration, the CPU 3 of the optical disc drive 1 according to the present invention controls the laser diode 8B by the control timing signal based on the initial write strategy which is a predetermined write strategy, thereby the initial write strategy. A calibration mark having a standard mark length of 3T to 14T defined by a standard corresponding to the optical disc 20 which is a predetermined standard is formed by irradiating the laser beam based on the above. Then, the CPU 3 reads a mark that is a recording mark, generates a binarized reproduction signal that is a reproduction signal corresponding to the mark, and an actual signal length MR that represents the actual mark length of the mark in the binarized reproduction signal. When the initial write strategy is corrected by generating the first correction write strategy based on the difference that is the difference between the standard signal length MT and the theoretical signal length MT representing the standard mark length, The theoretical signal length MT for a 3T mark having a small size is set in advance to the length of the binarized reproduction signal corresponding to the mark of the actual mark length 3T + T / 16, whereby the 3T mark has a predetermined additional length T / The first correction write strategy is generated so that the actual mark length is 3T + T / 16 longer by 16.

  As a result, the CPU 3 can form a 3T mark on the optical disc 20 with an actual mark length of 3T + T / 16, so that an increase in jitter in the time axis direction due to the length of the 3T mark being increased by T / 16 in the reproduction RF signal. As a result, it is possible to increase the effect of reducing jitter caused by the increase in the slope near the zero level ZL due to the increased peak portion, and as a whole, the jitter in the reproduced RF signal can be reduced.

  Further, the CPU 3 can reduce the jitter in the reproduction signal in the low laser power region by increasing the peak portion in the reproduction RF signal of the 3T mark, so that the target range where the jitter in the reproduction signal is equal to or less than a predetermined value. Can be expanded in the direction of low laser power, and the optimum power value at the center of the target range can be reduced.

  Further, the CPU 3 repeats the step SP1, which is a recording step, the step SP2, which is a reproduction step, and the step SP3, which is a generation step, using a correction strategy generated immediately before, over a predetermined number of repetitions. The obtained third corrected write strategy is stored in the storage unit 4 in association with the optical disc 20, so that it is set as the set write strategy.

  Thereby, since the CPU 3 can feed back the correction result of the write strategy, it is possible to reduce the jitter of the reproduction signal corresponding to the 3T mark and to further improve the noise tolerance.

  According to the above configuration, the CPU 3 of the optical disc drive 1 of the present invention irradiates the optical disc 20 with laser light based on the initial write strategy, and calibrates standard mark lengths 3T to 14T defined by the standard corresponding to the optical disc 20. A binarized reproduction signal which is a reproduction signal is generated by reading processing of the mark, and an actual signal length MR and a standard mark length representing the actual mark length of the mark in the binarized reproduction signal When the first correction write strategy is generated based on the difference that is the difference from the theoretical signal length MT representing the first correction write strategy, the 3T mark is set to the actual mark length 3T + T / 16 which is longer by T / 16. By doing so, the quality of the reproduction RF signal can be improved.

(5) Other Embodiments In the above-described embodiment, the case where the optical disk 20 is used has been described. However, the present invention is not limited to this, and examples of the optical disk 20 include a DVD and a Blu-ray disc. Various optical discs such as (Blu-ray Disc), CD (Compact Disc), and HD (High Definition) disc can be used.

  In the above-described embodiment, the case where the actual mark length of the 3T mark is set to be longer than 3T has been described. However, the present invention is not limited to this, and the standard mark smaller than the predetermined length depending on the state. The actual mark length may be increased. For example, the actual mark length may be increased for the 3T mark and the 4T mark. For example, in a Blu-ray disc using a 2T mark, the actual mark length of the 2T mark may be increased, or the actual mark length of two or more marks (for example, 2T and 3T marks) may be increased.

  In the above-described embodiment, the case where the actual mark length of the 3T mark is set to be longer than 3T by T / 16 has been described. However, the present invention is not limited to this, and is longer by T / 16 to T / 32. By doing so, the same effect as the embodiment can be obtained.

  Further, in the above-described embodiment, the case where the generation of the correction write strategy is executed over a predetermined number of repetitions has been described. However, the present invention is not limited to this, and may be executed only once. good. In this case, since the number of processes of the CPU 3 can be reduced, the processing load on the CPU 3 can be reduced and the processing time can be shortened.

  Furthermore, in the above-described embodiment, the case where the generation of the correction write strategy is executed over a predetermined number of repetitions has been described. However, the present invention is not limited to this, and the actual signal length MR of each mark is determined in advance. You may make it repeat the production | generation of the correction | amendment write strategy mentioned above until it enters in the error threshold value range of the set theoretical signal length MT. As a result, the CPU 3 can set a high-accuracy corrected write strategy that surely falls within the error threshold range in which the actual signal length MR is set as the set write strategy for the optical disc 20.

  Further, in the above-described embodiment, the case where the optical disc drive 1 executes the above-described write strategy setting process has been described. However, the present invention is not limited to this, and the write strategy setting program is stored in the storage unit 4. Alternatively, an external write strategy setting device having the control IC 2 may execute the write strategy setting process.

  In this case, for example, the write strategy setting device executes a setting process for the write strategy stored in the optical disc drive 1 or the optical pickup 8 before product shipment. That is, the write strategy setting device forms a mark based on the write strategy stored in the storage unit built in the optical disk drive 1 or the optical pickup 8 and corrects based on the reproduction signal acquired from the optical disk drive 1 or the optical pickup 8. A write strategy is generated, and the correction strategy is stored as an initial setting value in a storage unit built in the optical disc drive 1 or the optical pickup 8.

  Further, in the above-described embodiment, the recording medium includes the optical pickup 8 as the recording unit, the signal processing unit 9 as the reproducing unit, the write strategy generating unit 10 as the correcting unit, and the storage unit 4 as the setting unit. Although the case where the optical disk drive 1 as a driving device is configured has been described, the present invention is not limited to this, and the recording medium includes a recording unit, a reproducing unit, a correcting unit, and a setting unit according to various other configurations You may make it comprise a drive device, an optical pick-up module, and a light strategy setting apparatus.

  The write strategy setting method, the write strategy setting device, the recording medium driving device, the pickup module, and the recording medium of the present invention can be used for setting the write strategy for various optical disks such as an optical disk and a Blu-ray disk.

1 is a schematic diagram showing an overall configuration of an optical disc drive. It is an approximate line figure used for explanation of generation of a timing control signal. It is a basic diagram with which it uses for description of the production | generation of a reproduction signal. It is a basic diagram with which it uses for description of the production | generation of the timing control signal in this Embodiment. It is a basic diagram with which it uses for description of the effect of + T / 16. It is a basic diagram which shows the write strategy setting process sequence. It is a basic diagram with which it uses for description of the production | generation of the conventional timing control signal. It is a basic diagram with which it uses for description of the waveform of reproduction | regeneration RF signal.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Optical disk drive, 2 ... Control IC, 3 ... CPU, 4 ... Memory | storage part, 8 ... Optical pick-up, 9 ... Signal processing part, 10 ... Laser driver, 8A ... Write strategy production | generation part.

Claims (5)

A recording step of forming a predetermined recording mark on the optical disc by irradiating the optical disc with laser light based on an initial write strategy by the recording means;
A reproduction step of reading out the recording mark formed on the optical disc by a reproducing means and generating a reproduction signal corresponding to the recording mark;
The initial write strategy is set so that the actual mark length matches the standard mark length according to the difference between the actual mark length of the recording mark based on the reproduction signal and the standard mark length defined by a predetermined standard. A correction step for correcting by the correction means;
A setting step of setting a correction write strategy obtained as a result of correction by the correction step with respect to the optical disc as a setting write strategy for the optical disc by a setting means,
In the above correction step,
A write strategy setting method for correcting the initial write strategy so that an actual mark length of a recording mark having the minimum standard mark length among the recording marks is longer than the standard mark length by a predetermined additional length. In the above write strategy setting method,
The write strategy setting method according to claim 1, wherein the flow of the recording step, the reproducing step and the correcting step is repeated a plurality of times. A recording means for forming a predetermined recording mark on the optical disc by irradiating the optical disc with laser light based on an initial write strategy;
Reproduction means for reading out the recording mark formed on the optical disc and generating a reproduction signal corresponding to the recording mark;
In accordance with the difference between the actual mark length of the recording mark based on the reproduction signal and the standard mark length defined by a predetermined standard, the initial write strategy is set so that the actual mark length matches the standard mark length. Correction means for correcting;
Setting means for setting a correction write strategy obtained as a result of correction by the correction means for the optical disc as a setting write strategy for the optical disc,
In the correction means,
A write strategy setting device for correcting the initial write strategy so that an actual mark length of a recording mark having a minimum standard mark length among the recording marks is longer than the standard mark length by a predetermined additional length. Drive means for rotationally driving the optical disc;
Recording means for forming a predetermined recording mark on the optical disc by irradiating the optical disc with a laser beam based on an initial write strategy;
Reproduction means for reading out the recording mark formed on the optical disc and generating a reproduction signal corresponding to the recording mark;
The initial write strategy is set so that the actual mark length matches the standard mark length according to the difference between the actual mark length of the recording mark based on the reproduction signal and the standard mark length defined by a predetermined standard. Correction means for correcting;
Setting means for setting a correction write strategy obtained as a result of correction by the correction means for the optical disc as a setting write strategy for the optical disc,
In the correction means,
A recording medium driving apparatus that corrects the initial write strategy so that an actual mark length of a recording mark having the minimum standard mark length among the recording marks is longer than the standard mark length by a predetermined additional length. Recording means for forming a predetermined recording mark on the optical disc by irradiating the optical disc with laser light based on an initial write strategy;
Reproduction means for reading out the recording mark formed on the optical disc and generating a reproduction signal corresponding to the recording mark;
The initial write strategy is set so that the actual mark length matches the standard mark length according to the difference between the actual mark length of the recording mark based on the reproduction signal and the standard mark length defined by a predetermined standard. Correction means for correcting;
Setting means for setting a correction write strategy obtained as a result of correction by the correction means for the optical disc as a setting write strategy for the optical disc,
In the correction means,
A pickup module that corrects the initial write strategy so that an actual mark length of a recording mark having the minimum standard mark length among the recording marks is longer than the standard mark length by a predetermined additional length.

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