JPH08167149A - Rewritable optical recording/reproducing device - Google Patents

Abstract

PURPOSE: To provide a rewritable optical recording/reproducing device capable of dissolving a long time problem of a processing time and the mismatch of set recording power by deciding optimum recording power with the number of minimum recording times. CONSTITUTION: A test recording control circuit 11 performs the setting of lower limit recording power being a result subtracting a prescribed low band margin value from a prescribed initial recording power value read out from a memory circuit 13 and the output instruction of a recording current (b) equivalent to the power value to a laser drive circuit 2, and supplies the test data g to a recording pulse correction circuit 1, and executes test recording to a relevant test, track by operation similar to regular information recording processing. The test recording control circuit 11 is inputted with an error rate decision signal from a regenerative error rate decision circuit 10, and performs test recording/reproducing at upper limit recording power when the decision result of a regenerative error rate is normal, and performs the search processing of the optimum recording power when abnormal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rewritable optical recording / reproducing apparatus, and more particularly to recording / reproducing binary digital information on an optical recording medium by using optical means and rewriting information on the medium. The present invention relates to a rewritable optical recording / reproducing device having a function, such as a magneto-optical disk device.

[0002]

2. Description of the Related Art In a rewritable optical recording / reproducing apparatus such as a magneto-optical disk apparatus, laser light having a semiconductor laser diode or the like as a light source is used as an information recording / reproducing means. It is focused on and irradiated onto a recording medium.

At the time of recording information, the medium surface is irradiated with laser light whose intensity is modulated in accordance with the supplied recording data, while an external magnetic field is supplied to the medium surface, and the laser light causes local irradiation. Information is recorded by forming a magnetization reversal mark on the portion of the surface of the medium whose temperature has been raised. Further, at the time of reproducing information, the medium surface is irradiated with a laser beam of a predetermined constant intensity that does not disturb the stored information, and the polarization plane change of the reflected light corresponding to the magnetization reversal mark is detected as an electric signal,
After conversion into a binary signal, information reproduction is performed from reproduction timing discrimination using the reproduction clock signal as a discrimination reference.

In the above-described recording / reproducing process, the task is to ensure how low the error rate at the time of reproducing information is as a result. Particularly, at the time of recording, it is required that the recording power intensity of the laser beam be adapted to the recording sensitivity characteristic of the actually used medium to obtain stable mark formation.

Incidentally, under the condition that the recording power intensity is lowered from the appropriate value in the medium characteristics, the S / N ratio is deteriorated due to the reproduction signal level lowering due to unsaturated recording, and under the power condition increased from the appropriate value. The increase in signal interference causes a decrease in resolution and a shift in mark position, and in either case, the reproduction error rate increases.

Conventionally, the recording power in this rewritable optical recording / reproducing apparatus is determined in consideration of the variations in the recording sensitivity of the medium, variations in the apparatus such as focus shift, etc. However, since the margin can be secured relatively easily, A recording power value that allows the above variation is determined based on experimental verification, and this recording power value is fixedly used in the information recording process of the actual device.

However, with the recent trend toward higher recording densities or higher speeds in response to the demand for higher capacity / higher performance, the margin for the above recording power tends to decrease. In some cases, test recording / playback is performed using a test area outside the user's usage area on the medium, and the recording power optimization setting processing method that adapts the above recording power to the actually used medium by using the playback signal quality as a criterion is adopted. Is being started.

As an example, in Japanese Patent Laid-Open No. 3-171437, the recording power is gradually increased to perform test recording / reproduction, and the reproduction signal is first judged to be good from the judgment of the reproduction signal quality such as bit error. A method has been proposed in which a recording power (lower limit recording power) is detected and an optimum recording power is obtained by adding a predetermined power to the detected lower limit recording power.

The test area is not specified in the above-mentioned publication, but as an example, the specification of a 130 mm rewritable optical disk cartridge (ISO) by the International Electrotechnical Commission (IEC) of the International Organization for Standardization (ISO) is specified. / IEC10089 (JIS X 627
According to the format condition, as shown in FIG. 4, according to (1)), the inner peripheral area (29.80 mm to 30.
00mm) is defined as the manufacturer test area and the protective area,
And outer peripheral area (60.00mm-60.15mm)
Are defined as manufacturer test areas, and these inner and outer peripheral areas can also be used as the above test areas.

As a result, in the rewritable optical recording / reproducing apparatus, which is particularly aimed at large capacity / high performance, the test recording / reproduction in the test area to the recording power optimization setting process are executed, and it is suitable for the medium to be actually used. Information recording with a low reproduction error rate is achieved from the setting of the optimum recording power.

[0011]

However, in the above-described conventional rewritable optical recording / reproducing apparatus, the number of recordings in the test recording / reproduction is particularly reduced, although the test area is usually limited to a small area. The processing power is not taken into consideration as much as possible, and the optimally set recording power has a drawback that it is insufficient in confirming the optimality from the viewpoint of securing a margin.

That is, first, the recording power optimization setting process is executed under the starting conditions such as medium loading, power-on, and specified temperature change. The rewritable optical recording / reproducing apparatus is characterized by medium exchangeability. In consideration of only loading the medium, the recording power optimization setting process is frequently activated.

Further, in the processing method by the conventional apparatus, the initial value of the lower limit recording power is a fixed setting value determined from the design conditions, and in consideration of variations in the apparatus and recording sensitivity of the medium, it is inevitable that it will be repeated many times from one start. Test recording / reproduction is required. Therefore, a situation occurs in which the total number of test recordings in the test area is much larger than the total number of recordings in the actual user area.

On the other hand, the medium characteristics show characteristic deterioration as the number of recordings increases. Therefore, in the recording power optimization setting under the situation where the number of recordings in the test area is significantly larger than that in the user area as described above, optimum recording results. A situation arises in which the power does not match the medium characteristics of the user area originally intended for optimization. In the conventional device described in the above-mentioned publication, the number of recordings is managed as a measure against the characteristic deterioration of the test area. However, the function of the device is complicated, and the test area is finite. The deterioration of medium characteristics is not basically solved.

Further, in the recording power optimization setting process of the conventional apparatus, since the test recording / reproduction is executed almost unconditionally many times as described above, the processing time required for the optimization setting becomes long. It also has points.

Further, in the recording power optimization setting process of the conventional apparatus, the optimum recording power is determined from the addition of the predetermined power after the detection of the lower limit power, so that it is certain that the desensitization factor such as the focus deviation is caused. Although it is possible to secure a margin corresponding to the above-mentioned predetermined power, there is also a drawback that a margin is not guaranteed at all with respect to sensitivity increase factors such as variations in medium recording sensitivity.

The present invention has been made in view of the above points,
An object of the present invention is to provide a rewritable optical recording / reproducing apparatus capable of solving the problem of lengthening the processing time and incompatibility of the set recording power by determining the optimum recording power with the minimum number of recordings.

[0018]

In order to achieve the above-mentioned object, the present invention uses a light beam to record test data in a predetermined area on a rewritable optical recording medium at a specified recording power, Test recording / reproducing means for reproducing the test data, reproduction quality judging means for judging the reproduction quality by comparing the test data reproduced from a predetermined area with the recording test data, and a predetermined initial recording power to a predetermined low range margin power. And a test recording control means for instructing the test recording / reproducing means as the recording power to which the lower limit recording power obtained by subtracting is applied, and for performing the recording power optimization setting according to the reproduction quality judgment result by the reproduction quality judging means. Is.

The test recording control means of the present invention includes at least the recording power optimization set value in the recording power optimization setting process executed immediately before as the predetermined initial recording power, and the reproduction quality judgment result at the lower limit recording power. If it is determined that the recording power is good, the initial recording power is set to the optimum recording power in the recording power optimization processing.

Further, the test recording control means of the present invention, when the reproduction quality judgment result at the lower limit recording power is good,
Subsequently, test recording / reproduction is also performed at the upper limit recording power obtained by adding a predetermined high band margin power to the initial power, and when the reproduction quality determination result is determined to be good, the initial recording power is set to the recording power optimization setting. The optimum recording power is set in the processing.

Further, the test recording control means of the present invention includes, as the predetermined initial recording power, at least the recording power optimization setting value in the recording power optimization setting process executed immediately before, and appropriately changes the low frequency margin power. Test recording and reproduction are repeatedly performed to detect the maximum low range margin power value at which the reproduction quality determination result is determined to be good, and the low range margin power initial setting value is subtracted from the low range margin power maximum value. The recording power correction value is calculated, and the optimum recording power search process for obtaining the updated recording power from the result of subtraction correction of the predetermined initial recording power by the recording power correction value is executed, and the updated recording power is set in the recording power optimization setting process. The optimum recording power may be set.

Further, the test recording control means of the present invention, following the optimum recording power search processing, uses the upper limit recording power obtained by adding the predetermined high frequency margin power to the update recording power as the recording power to the test recording / reproducing means. After instructing and performing test recording, reproduction is performed at a predetermined power, and when the reproduction quality judgment result by the reproduction quality judgment means is good, the updated recording power is set to the optimum recording power in the recording power optimization setting process. You may do it.

Further, the test recording / reproducing means of the present invention reproduces the test data after recording and reproducing the test data in each of the inner peripheral side area and the outer peripheral side area of the user use area of the disc-shaped optical recording medium. , The inner circumference optimum recording power obtained by the recording power optimization setting processing in the inner circumference side area and the outer circumference optimum recording power obtained by the recording power optimization setting processing in the outer circumference side area in the radial direction of the optical recording medium. The optimum recording power at each track position is set based on the result of interpolation calculation from the radial position at each track position.

The reproduction quality judging means of the present invention calculates the reproduction error rate and judges that the reproduction signal quality is good when the reproduction error rate is within a predetermined value.

Further, the reproduction quality judgment means of the present invention reproduces the respective test data reproduced from each of the plurality of sectors after the test recording / reproduction means recorded the plurality of sectors of the predetermined area with the same recording power. Find the error rate,
The average reproduction error rate is detected from those average values, and the reproduction signal quality is determined to be good when the average reproduction error rate is within a predetermined value.

Further, the reproduction quality judging means of the present invention is configured such that the test recording / reproducing means records the test data on the odd sectors in a plurality of predetermined areas with the same recording power and then reproduces the respective test data from each of the odd sectors. A reproduction error rate is obtained for each of the cases, and when the reproduction error rate is within a predetermined value set in advance, it is determined that the sector is good, and when the number of good determination sectors is a majority, the reproduction signal quality is determined to be good. May be.

[0027]

According to the present invention, the test data is recorded in the predetermined area of the optical recording medium with the lower limit recording power obtained by subtracting the predetermined low band margin power from the predetermined initial recording power, and this is reproduced, and the reproduction quality judgment is made by the reproduction quality judgment means. Since the recording power optimization setting is executed according to the result, it is possible to significantly reduce the number of times of recording / reproducing of test data, as compared with the conventional apparatus which requires unconditionally a large number of times of test recording / reproducing. .

Further, in the present invention, the predetermined initial recording power includes at least the recording power optimization setting value in the recording power optimization setting process executed immediately before, and the reproduction quality determination result at the lower limit recording power is determined to be good. In this case, the initial recording power is set as the optimum recording power in the recording power optimization process, and then the test recording / reproduction is also executed at the upper limit recording power obtained by adding the predetermined high frequency margin power to the initial power, and the reproduction quality concerned. When it is determined that the determination result is good, the initial recording power is set to the optimum recording power in the recording power optimization setting process, and therefore the first determination can be made by a total of two test recordings.

Further, according to the present invention, the difference between the maximum low band margin power value at which the reproduction error rate is determined to be good and the initial low band margin power predetermined value is obtained from the test recording / reproduction in which the low band margin power is changed. Is detected and the initial recording power is corrected by the difference value to obtain the optimum recording power, thereby shortening the processing time related to the optimization setting processing.

[0030]

Next, an embodiment of the present invention will be described. FIG. 1 is a block diagram of an embodiment of a rewritable optical recording / reproducing apparatus according to the present invention. In this embodiment, a recording pulse correction circuit 1, a laser drive circuit 2, an optical head 3, an optical disk 4, a spindle motor 5, an amplification circuit 6, a reproduction equalization circuit 7, a reproduction pulse conversion circuit 8, a reproduction data discrimination circuit 9, a reproduction circuit. Error rate determination circuit 10, test recording control circuit 11, track control circuit 1
2 and a memory circuit 13.

The optical head 3 has a laser diode (L
D) 301 and photodetector (PD) 302, and is configured to be movable in the radial direction of the optical disc 4 by a transfer mechanism (not shown). The optical disc 4 is a magneto-optical disc, and the magnetic reversal mark 401 is formed on the magnetic film.
Are formed. The spindle motor 5 has its motor shaft fixed to the center hole of the optical disc 4, and rotates the optical disc 4 based on the output of a rotation control means (not shown) so that the linear velocity with the optical spot of the optical head 3 becomes constant, for example. .

Next, the operation of this embodiment will be described.
First, a recording / reproducing operation for normal user information will be described. At the time of writing information, the write data signal a is supplied to the recording pulse correction circuit 1, where the stable magnetization of the optical disk 4 is performed depending on the medium recording sensitivity characteristic or the linear velocity condition of the track position (medium radial position) to be recorded. Recording waveform shaping and timing correction are performed so as to form the inversion mark 401.

The write data signal extracted from the recording pulse correction circuit 1 is supplied to the laser driving circuit 2 and corresponds to the recording laser light intensity optimized for the medium recording sensitivity and the like as described later. After being converted into the recording current b, it is supplied to the LD 301 in the optical head 3 and is current-driven.

The LD 301 emits a laser beam having a light intensity proportional to the supplied recording current b. This laser light is condensed by an optical lens (not shown) provided in the optical head 3, forms a light spot on the medium surface of the optical disc 4 which is rotationally driven by the spindle motor 5, and is irradiated. .

On the other hand, although not shown in FIG. 1, an external magnetic field having a polarity different from that at the time of erasing is applied on the medium surface of the optical disk 4 at the time of recording by a magnetic field generating means such as a bias coil. The temperature locally rises only in the medium portion where the light spot is formed, and the magnetization reversal mark 401 in the same direction as the external magnetic field is formed, whereas in the portion where the light spot is not formed, the temperature does not rise and the magnetization is reversed. Since the reversal is not performed, the magnetization direction of the magnetic film remains in the same direction as that at the time of erasing.

As described above, the light intensity of the laser light is modulated by the write data signal a, and light spots are substantially intermittently formed on the medium surface of the optical disc 4. For this reason, the magnetization reversal marks 401 in a minute region that is approximately the same size as the light spot are intermittently formed, so that the write data a is recorded on the optical disc 4 as a change in the magnetization direction.

Next, the operation of reproducing information will be described. First, the laser drive circuit 2 supplies a drive current corresponding to a predetermined constant intensity optical output that does not disturb the recorded information on the optical disc 4 to the LD 301 and current-drives it. As a result, the laser light having the predetermined constant light intensity emitted from the LD 301 is reflected after being irradiated onto the medium surface of the optical disc 4.

Since the plane of polarization of this reflected light rotates in accordance with the direction of magnetization due to the Kerr effect, the optical head 3 has a well-known polarization plane detecting means (not shown) provided inside thereof to polarize the reflected light. The change in the surface is taken out as a change in the amount of light and is incident on the PD 302, thereby converting it into an electric signal.

The electric signal taken out from the PD 302 is inputted to the amplifier circuit 6 as a reproduced analog signal c corresponding to the recorded information, amplified to a required level, and reproduced by the reproduction equalizer circuit 7 due to waveform interference. After distortion compensation equalization is performed, it is supplied to the reproduction pulse conversion circuit 8. The reproduction pulse conversion circuit 8 compares the input reproduction analog signal after reproduction equalization with the threshold level to generate a reproduction data pulse d which is a binary digital signal. The reproduction data pulse d is supplied to the reproduction data discriminating circuit 9, and the read data signal e is detected from the reproduction timing discrimination using the reproduction clock signal phase-synchronized with the reproduction signal as a discrimination reference to reproduce information.

The above is the same recording / reproducing operation as the conventional one, but in the present embodiment, the discrimination margin in the data discriminating circuit 9 is reduced as the recording density is increased and the recording / reproducing process is speeded up. In view of the fact that the laser light intensity during recording (hereinafter referred to as recording power) has a great influence, test recording / reproduction is performed in a test area outside the user data area, and the recording power is set to the recording sensitivity of the actual medium used. The recording power optimization setting process adapted to the variation is performed.

In this case, first, the test start signal f is set to the test recording control circuit 1 with the power-on of the apparatus, the loading of the medium, the temperature change above the specified value, or the recording error as the starting condition.
1, the test recording control circuit 11 performs track selection in a test area composed of a plurality of tracks, drives the track control circuit 12, and specifies the light beam position of the optical head 3 on the test track. Set to position.

After that, the test recording control circuit 11 reads out a predetermined initial recording power from the memory circuit 13,
The lower limit recording power, which is the result of subtracting the predetermined low-range margin power value from the initial recording power value, and the instruction to output the recording current b corresponding to the same power value to the laser drive circuit 2 and the recording of the test data g The pulse correction circuit 1 is supplied, and the test recording on the test track is performed from the same operation as the normal information recording process.

As for the initial recording power, when there is no actual record of the recording power optimization setting in the same apparatus such as power-on or first medium loading, the fixed setting initial value determined from the experimental result is used. The value is read from the memory circuit 13 and used. If the recording power optimization setting has already been executed in the past with the temperature change, elapsed time, recording error, etc. as the start conditions, the optimization with the recording power optimization setting executed immediately before is performed. The recording power value is read from the memory circuit 13 and used.

Further, as the low frequency margin power, a fixed value determined based on an experiment is usually used for the purpose of ensuring a margin for recording sensitivity variation in the medium surface, recording power setting variation and the like. . However, the fixed value is not limited to this, and the fixed value may be changed in the retry when the recording power optimization process fails.

Next, the test data recorded on the test track with the lower limit recording power is read by the same procedure as the above-mentioned normal information reproduction, and is read out from the reproduction data discriminating circuit 9 as a binary read data signal e. It is supplied to one input terminal of the reproduction error rate determination circuit 10. The reproduction error rate determination circuit 10 is supplied with the test data g itself used for the test recording to the other input terminal. Here, after detecting the reproduction error rate from the comparison between the two, this detected reproduction error rate is It is determined whether or not it is within a predetermined prescribed value determined in advance, and an error rate determination signal h indicating the determination result is generated.

The test recording control circuit 11 receives the error rate judgment signal h and executes any of the following controls according to the judgment result of the reproduction error rate.

When the reproduction error rate is judged to be good within the specified value, the upper limit recording power, which is the result of adding the predetermined high frequency margin power to the initial recording power, is continued in the test recording control circuit 11. Then, the laser drive circuit 2 is instructed to output the recording current b corresponding to, and the same test recording / reproducing as the test recording / reproducing at the lower limit recording power is executed. As a result, only when it is determined that the reproduction error rate at the upper limit recording power is good, the initial recording power is recognized as the optimum recording power in the main recording power optimization setting process, and the process ends. On the other hand, when a good result is not obtained by the reproduction error rate determination, the process shifts to the optimum recording power search process as in the following case.

The high band margin power is set through an experimental study for the purpose of securing a margin in the high power band against variations in recording power setting, like the low band margin power. FIG. 2 schematically shows an example of reproduction signal amplitude characteristics with respect to recording power, and FIG. 3 schematically shows an example of reproduction error rate characteristics with respect to recording power. Since the reproduction signal amplitude has not dropped below the specified value and the reproduction error rate has not increased above the specified value, it has been confirmed that the test recording / reproduction at the lower limit recording power ensures a margin in the low power range. In addition, it is possible to further ensure the optimality of the initial recording power by confirming that the margin is secured in the high power range from the test recording / reproducing at the upper limit recording power.

When the reproduction error rate is not equal to or higher than the specified value and is not judged to be good, the process shifts to the optimum recording power search process described in detail below.

In the search process for the optimum recording power, first, the test recording control circuit 11 appropriately changes the value corresponding to the low band margin power (in the case where the reproduction error rate is not judged to be good at the above upper limit recording power, the lower limit is successively increased / decreased). When the reproduction error rate is not determined to be good by the recording power, the lower limit recording power is determined by subtracting it from the initial recording power.

After that, the test recording / reproducing with the lower limit recording power is executed in the same manner as described above, and the reproducing error rate judging circuit 1
It is repeatedly executed while changing the low range margin power so as to detect the maximum low range margin power for obtaining a good judgment from the reproduction error rate determination result from 0, in other words, the minimum lower limit recording power.

Next, the test recording control circuit 11 subtracts the initial predetermined low band margin power from the low band margin power maximum value obtained as a result of the above processing to calculate the recording power correction value, and further, from the initial recording power. The recording power correction value is subtracted to determine the updated recording power.

Subsequently, the test recording control circuit 11 sets the upper limit recording power from the addition of the predetermined high band margin power to this updated recording power, and similarly the test recording / reproduction at the upper limit recording power to the reproduction error rate determination. In this case, the updated recording power is obtained as the optimum recording power in the recording power optimization setting process, and the process is terminated. The test recording control circuit 11 stores the optimum recording power in the memory circuit 13 or performs an updating process prior to the end of the process, and this recording power is used in the subsequent user information recording process.

Even in the above-described optimum recording power search process, if normal processing cannot be completed,
Change test track or low range margin power /
Retry is executed including the change of the high frequency margin power, but if the normal termination is still not obtained, the warning display of abnormalities or the recording process under abnormal recording power condition from the upper report is avoided. Measures are taken.

As can be seen from the above-described embodiments, in the present invention, when the recording power is optimized, the initial value determined from the design conditions or the optimum recording power value in the immediately previous optimization setting is used. Then, the test recording / reproduction is performed at the lower limit recording power and the upper limit recording power, and the first judgment is made by a total of two test recordings.

Normally, unless there is a sudden deterioration in the device state,
In particular, the optimum recording power does not largely deviate from the optimum value of the immediately preceding execution, and in this sense, it is often the case that the recording power optimization setting process ends in the first determination.
Compared with the conventional method that requires a large number of test recordings almost unconditionally, the processing can be significantly shortened. In addition, even when the search process for the optimum recording power becomes necessary, the optimum value in the immediately preceding optimization setting can be set in comparison with the conventional method in which the recording power is unconditionally sequentially increased from the fixedly set initial value. It is apparent that the present invention in which the lower limit recording power is searched by changing the margin power on the basis of the standard has a high processing speed, and the effect of reducing the number of test recordings can be obtained.

Further, in the above embodiment, the margin check in the high power range is executed from the test recording / reproduction at the upper limit recording power obtained by adding the predetermined high range margin power to the initial recording power or the update recording power. However, if the high power margin is sufficiently secured in the design conditions, it can be deleted. In this case, it is possible to further reduce the number of recordings and the processing time. .

Although the optimum recording power in the test area is determined from the recording power optimization setting processing operation described above, in an apparatus for rotating a disk-shaped medium at a constant rotation speed, the linear velocity on the medium is determined. Due to the difference, the recording sensitivity is not uniform, and the optimum recording power usually varies depending on the medium radial position.

Therefore, test areas are provided in the innermost and outermost areas outside the user use area (for example,
The test recording control circuit 11 drives the track control circuit 12 to set the light beam position of the optical head 3 to each test track position and to set the optimum recording power. The process is executed to determine the optimum inner recording power and the optimum outer recording power. After that, the optimum recording power at each radial position is determined by the following linear interpolation calculation.

Now, assuming that the inner and outer circumference test track radial positions are R1 and R0, the inner and outer circumference optimum recording powers are P1 and P0, respectively, and the radial position of an arbitrary track is r, the optimum recording at the r position is performed. The power P is expressed by the following equation P = P1 + (P0-P1) * (r-R1) / (R0-R
It is represented by 1).

In the above interpolation calculation, linear interpolation is shown as an example, but the invention is not particularly limited to this, and an approximate calculation formula which is obtained by performing characteristic approximation from experimental evaluation under actual device conditions is used. It may be used.

Furthermore, the recording format in these devices is
It is general that a track corresponding to one round of the medium is divided into a plurality of blocks called sectors, and recording / reproduction is performed in sector units, and the above-described recording power optimization setting process is also performed in sector units. Is desired. However, since the recording sensitivity of the medium does not guarantee uniform characteristics within the medium surface, especially within one round, determining the optimum recording power from test recording / reproduction in a single sector is a consideration for variations. In that respect, it is not preferable. For this reason,
It is necessary to average the reproduction error rate within the track, and the following method is adopted.

In the first method, the test recording control circuit 11 performs test recording / reproduction on a plurality of sectors under the same recording power condition, totals the reproduction error rate in each sector, and calculates the average reproduction error rate. This is a method of calculating and using as a judgment criterion whether or not this average reproduction error rate is within a predetermined prescribed value.

In the second method, the test recording control circuit 11 executes the same test recording / reproduction on a plurality of odd-numbered sectors under the same recording power condition, and the reproduction error rate judgment result in each sector is sector-by-sector unit. This is a method in which the quality is totaled and a criterion is obtained from a secondary determination result as to whether or not the number of sectors determined to be good satisfies a majority.

Further, in the above-mentioned embodiments, the reproduction error rate judgment circuit 10 is used when the recording power is optimized.
The criterion is that the reproduction error rate is within a specified value, but it is not particularly limited as long as it is a means for judging the signal quality of the reproduced signal. It is also possible to make a determination when the resolution (the reproduction signal amplitude ratio at the highest recording density and the lowest recording density) is within a specified range. The object is achieved by providing a reproduction signal amplitude determination circuit when the reproduction signal amplitude is the determination reference and a reproduction resolution determination circuit when the resolution is the determination reference instead of the reproduction error rate determination circuit 10.

In the above embodiments, a rewritable optical recording / reproducing apparatus using a magneto-optical recording medium as a recording medium is shown, but a phase change type recording information based on the state transition between crystalline and amorphous. Even when targeting a recording medium, it is possible to achieve the optimum setting of the recording power with the same circuit configuration requirements.

[0067]

As described above, according to the present invention,
If a predetermined margin power is secured in the recording power optimization setting process, the lower limit recording power is included as the predetermined initial recording power including at least the recording power optimization setting value in the recording power optimization setting process executed immediately before. If it is determined that the reproduction quality is determined to be good, the initial recording power is set to the optimum recording power in the recording power optimization process, and then the upper limit recording power obtained by adding the predetermined high frequency margin power to the initial power is selected. When the test recording / reproduction is also executed and the reproduction quality judgment result is judged to be good, the initial recording power is set to the optimum recording power in the recording power optimization setting process, or the low-pass margin power is changed. From the test recording / reproduction, the maximum low range margin power value at which the reproduction error rate is judged to be good and the initial low range mar Detecting a difference between Npawa predetermined value,
By setting the optimum recording power as the result of correcting the initial recording power with the difference value, the number of times of recording / reproducing test data can be significantly reduced compared to the conventional device that requires unconditionally many times of test recording / reproducing. Therefore, the processing time associated with the optimization setting processing is shortened, so that it is possible to prevent the deterioration of the medium characteristics in the test data recording / reproducing area due to an increase in the number of unnecessary test recordings. As a result, it is possible to set the optimum recording power that matches the characteristics of the user area of the actually used medium, and it is possible to always achieve information recording / reproduction with a low reproduction error rate.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a diagram showing an example of recording power versus reproduction signal amplitude characteristics.

FIG. 3 is a diagram showing an example of recording power versus reproduction error rate characteristics.

FIG. 4 is a diagram showing an example of a specified area of an optical disc.

[Explanation of symbols]

 1 recording pulse correction circuit 2 laser drive circuit 3 optical head 4 optical disk 5 spindle motor 7 reproduction equalization circuit 8 reproduction pulse conversion circuit 9 reproduction data discrimination circuit 10 reproduction error rate judgment circuit 11 test recording control circuit 12 track control circuit 13 memory circuit

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G11B 20/18 501 501940-5D

Claims (9)

[Claims] 1. A test recording / reproducing device for reproducing test data with a predetermined power after recording the test data with a light beam in a predetermined area on a rewritable optical recording medium with a designated recording power. Reproduction quality judgment means for judging reproduction quality by comparing the test data reproduced from the area with the recording test data, and the lower limit recording power obtained by subtracting a predetermined low band margin power from a predetermined initial recording power, the test recording / reproducing means And a test recording control means for executing recording power optimization setting according to the reproduction quality judgment result by the reproduction quality judgment means. 2. The test recording control means includes, as the predetermined initial recording power, at least a recording power optimization setting value in a recording power optimization setting process executed immediately before,
2. The rewritable optical recording according to claim 1, wherein when the reproduction quality determination result at the lower limit recording power is determined to be good, the initial recording power is set to the optimum recording power in the recording power optimization processing. Playback device. 3. The test recording control means, when the reproduction quality judgment result at the lower limit recording power is good, subsequently the test recording / reproduction at the upper limit recording power obtained by adding a predetermined high frequency margin power to the initial power. 3. When the reproduction quality determination result is determined to be good, the initial recording power is set to the optimum recording power in the recording power optimization setting process.
The rewritable optical recording / reproducing apparatus described. 4. The test recording control means includes at least a recording power optimization setting value in a recording power optimization setting process executed immediately before as the predetermined initial recording power,
Test recording / reproduction is repeatedly performed by appropriately changing the low-range margin power, and a maximum low-range margin power value at which the reproduction quality determination result is determined to be good is detected. A recording power correction value is calculated by subtracting the initial setting value of the area margin power, and an optimum recording power search process for obtaining an updated recording power from the result of subtraction correction of the predetermined initial recording power with the recording power correction value is executed, The rewritable optical recording / reproducing apparatus according to claim 1, wherein the update recording power is set to an optimum recording power in the recording power optimization setting process. 5. The test recording control means, following the optimum recording power search processing, sets an upper limit recording power obtained by adding a predetermined high frequency margin power to the update recording power to the test recording / reproducing means. , Make a test recording and then play back at a predetermined power,
5. The rewritable optical recording / reproducing apparatus according to claim 4, wherein the update recording power is set to the optimum recording power in the recording power optimization setting process when the reproduction quality judgment result by the reproduction quality judgment means is good. 6. The test recording / reproducing means records and reproduces the test data in each of an inner peripheral area and an outer peripheral area of a user-use area of the disc-shaped optical recording medium, and reproduces the test data. Is the optimum inner circumference recording power obtained by the recording power optimization setting processing in the inner circumference side area and the outer circumference optimum recording power obtained by the recording power optimization setting processing in the outer circumference side area. 2. The rewritable optical recording / reproducing apparatus according to claim 1, wherein the optimum recording power at each track position is set based on the result of interpolation calculation from the radial position at each track position in the radial direction. 7. The reproduction quality determination means calculates a reproduction error rate and determines that the reproduction signal quality is good when the reproduction error rate is within a predetermined value.
The rewritable optical recording / reproducing apparatus described. 8. The reproduction quality judgment means records the test data reproduced from each of the plurality of sectors after the test recording / reproduction means records the plurality of sectors of the predetermined area with the same recording power. A reproduction error rate is obtained, an average reproduction error rate is detected from the average value thereof, and the reproduction signal quality is judged to be good when the average reproduction error rate is within a predetermined value set in advance. Item 1. The rewritable optical recording / reproducing apparatus according to item 1. 9. The reproduction quality determination means records each test in the plurality of predetermined areas with the same recording power by the test recording / reproduction means on an odd sector and then reproduces each test from each of the odd sectors. Obtain the reproduction error rate for each data, determine that the sector is good when the reproduction error rate is within a predetermined value, and determine that the reproduction signal quality is good when the number of good determination sectors is a majority. The rewritable optical recording / reproducing apparatus according to claim 1.