JPH01112551A - Recording method for magneto-optical disk - Google Patents

Abstract

PURPOSE:To attain high speed control of an optimum laser beam output by using a standard magneto-optical disk device to form a standard data table, generating a real data table based on the table or the like to control the intensity of a recording laser beam. CONSTITUTION:The standard magneto-optical disk device is used at first to obtain the optimum laser beam output and the standard data table storing the output by the 2-dimensional address designation of the disk radius, and the operating temperature is generated and stored in a ROM 1 of the device in user actually. Then a changeover switch 16 is thrown to the position of a test signal generator 9. Then the actual optimum laser output is measured as to plural disk radii, then the output of the optimum laser beam in the actual device is obtained based on the optimum value, the disk radius, the operating temperature and the storage value in the ROM 1, the result is stored in a RAM 15 to generate the real data table. Then the switch 16 is thrown to the position of a recording signal to apply recording. Then the value of the optimum laser beam output corresponding thereto is read from the RAM 15 to control optimizingly the intensity of the recording laser beam.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording method for a magneto-optical disk during repetitive recording on a magneto-optical disk using a constant angular velocity force type called CAV method.

[Prior Art] A magneto-optical disk device performs thermal recording by changing the optical output of a semiconductor laser depending on the signal to be recorded. For example, NRZ (non-return
(to zero change at one) When performing recording, first, erasing is performed to set the entire disk to a bit "0" state. That is, while tracing the recording track with the head, a strong laser beam is irradiated to raise the temperature above the critical temperature (
During the cooling process, the magnet is magnetized in the direction of the erasing magnetic field generated by the external magnetic field, and the magnetization direction is uniformly aligned.

When recording the state of bit "1" of the recording signal after such erasure, the semiconductor laser light is emitted strongly as shown in the state of optical output Pm shown in FIG. It is heated above a critical temperature, and during the cooling process, the direction of magnetization by an external magnetic field (opposite to the erased magnetization direction) is reversed to record the state of bit "1". Further, when recording the rOJ state of the recording signal, the semiconductor laser light is weakly emitted like the state of the optical output Pb, the temperature of the irradiated part is not raised, and the magnetization direction is not reversed.

By the way, in a magneto-optical disk device of a constant angular velocity force type, the linear velocity changes for each radial position of the disk, so for example, an NRZ signal with a constant bit rate that repeats 1010... is recorded with a constant laser light output. In some cases, the size of the recorded bits differs depending on the radial position of the disk.

Assuming that the amount of energy per unit area of the laser beam is constant, the recording bit length (the length of the inverted portion of LA) due to the laser beam output Pm changes depending on the radial position of the disk, and as a matter of course, The bit length of the outer track is longer than the bit length of the inner track.

However, when the laser beam is kept constant, the amount of energy received by the outer track is smaller than the amount of energy per unit area received by the inner track from the laser light due to the difference in linear velocity. Therefore, the duty ratio of the reproduced signal is 50% at the reference track at the intermediate position in the radial direction.
When recording is performed on a track outside the reference track with a constant laser beam output such that The reproduction period T1 is shorter than the period T1, and conversely, the reproduction period T1 is longer for tracks located inside the reference track. FIG. 12 shows this situation.

[Problems to be solved by the invention] When the output of the recording laser beam is kept constant in this way,
The duty ratio (Tl) of the reproduced signal corresponding to the recording bit length
/T) is not always 50% on the outer or inner track, which has the disadvantage that the reproduced signal has a secondary amount.

Therefore, conventional methods for controlling laser light output during recording on a magneto-optical disk include methods of controlling the laser light output by dividing the disk into several recording areas according to the radial position of the disk, and methods of controlling the laser light output while keeping the laser light output constant. A method has been proposed in which the write pulse width is changed while the write pulse width remains unchanged. As the latter prior art, for example, Japanese Patent Publication No. 59-24452
Public notice is known.

However, although such conventional methods alleviate the above-mentioned drawbacks, they cannot sufficiently eliminate them.

To explain this in more detail, the characteristics of semiconductor laser light vary widely; for example, the threshold current is 60 mA to 80 mA, and the differential efficiency is 0.5 to 1.1, which has a considerably large characteristic distribution. Therefore, even if each magneto-optical disk device is controlled using predetermined control data, sufficient control is not possible.

On the other hand, for magneto-optical disks, for example, the environmental temperature T is 0°C to 50°C.
℃, and magneto-optical disk devices perform thermal recording by converging laser light. Therefore,
Even a slight change in the environmental temperature T changes the recording sensitivity of the recording medium. Furthermore, the characteristics of semiconductor laser light also change significantly with temperature changes; for example, the threshold current increases from 50 mA at 0°C to 70mA at 50°C. From the above, it is necessary to finely control the semiconductor laser light even in response to changes in the environmental temperature T.

Therefore, in order to create optimal recording conditions, the operating environment temperature cannot be ignored. For example, magneto-optical disk drives should be used in a constant temperature bath or in a room with strict room temperature control so that they are not affected by the environmental temperature. Although it is possible to do so, it increases the size of the device and limits the place where it can be used.
Disadvantages such as increased costs cannot be avoided.

That is, in a magneto-optical disk device, recording is performed by converging a laser beam onto a recording bit using a servo system such as auto-tracking or auto-focus, and increasing the temperature of the converged portion as described above. The state of the optical output Pb shown in FIG. 7 is the minimum optical output necessary to operate the servo system stably, and recording is not performed in this state. On the other hand, the state of optical output Pm is a high optical output and recording is performed. Therefore, the optical output Pb can be kept at a constant laser output, but the optical output pm has a large effect on the shape of the recording bits, so it is necessary to carefully control it in response to changes in the disk radial position and environmental temperature. There is.

[Means for Solving the Problems] The present invention has been made in view of such conventional problems, and in a magneto-optical disk capable of repeated recording, changes in the disk radius during recording and changes in the disk radius during recording. The recording laser light output can be controlled to the optimum value so that a reproduction signal without secondary particles is always obtained even if the environmental temperature changes, and the calculation processing for this optimum control can also be performed at high speed and easily. The purpose of the present invention is to provide a recording method for a magneto-optical disk.

In order to achieve this object, in the magneto-optical disk recording method of the present invention, first, a standard magneto-optical disk device is used to set the disk radius and operating environment temperature using parameters for a magneto-optical disk that can be repeatedly recorded. A standard data table is created in which the value of the optimum laser light output is stored by specifying the two-dimensional address of the disk radius and operating environment temperature, and the value of the magneto-optical disk device to be actually used is calculated. Store in ROM.

In a magneto-optical disk device having a ROM in which a standard data table is stored in this way, the corresponding optimum laser beam obtained from the standard data table is used for multiple locations at different disk radial positions through preliminary recording and reproduction prior to use. Actual reproduction/recording is performed using the optical output as an initial value, and the value of the actual optimum laser optical output that does not generate secondary particles is measured.

Once the actual optimum laser light output power can be measured for multiple disk radii in this way, the disk radius and use in the actual device can be determined based on this optimum value, the disk radius, the operating environment temperature, and the stored values in the standard data table. The optimum output value of the laser beam is determined using the environmental temperature as an instruction parameter, and this output value is stored in the RAM by specifying a two-dimensional address of the disk radius and the operating environment temperature to create and store an actual data table.

For recording after the actual data table is created in this way, the corresponding optimum laser light output is determined from the actual data table by specifying a two-dimensional address by detecting the disk radius corresponding to the operating environment temperature and head position at that time. The intensity of the recording laser beam is controlled to the optimum value by reading the value.

[Function] In the magneto-optical disk recording method of the present invention, the optimum laser light output to be used in the actual device is determined based on a standard data table through preliminary recording and reproducing processing prior to use of the device. For the actual recording operation to be performed afterwards, the optimal laser beam can be immediately determined by referring to the actual data table by detecting the disk radius corresponding to the operating environment temperature and head position at that time. Optimum control can be performed by reading the output value, and all you need to do is refer to the actual data table.
No arithmetic processing is required to find the optimum value, and control of the optimum laser light output can be achieved quickly and easily.

[Embodiment] FIG. 1 is a block diagram showing an embodiment of a magneto-optical disk device to which the recording method of the present invention is applied.

In FIG. 1, reference numeral 12 denotes a magneto-optical disk, which is set on the rotating shaft of a spindle motor 11 and rotated at a constant angular velocity, for example, 3600 rpm.

Here, as an example, the magneto-optical disk 12 has a radius of 3Qcm and a recording area having a radius of 5 to 15cm. An optical head 5 that is movable in the radial direction is provided at a position facing the recording surface of the magneto-optical disk 12, and the optical head 5 focuses the laser light from the semiconductor laser 10 and irradiates the recording surface with a beam spot. Erase, record or play. The intensity of the laser light output from the semiconductor laser 10 is determined by the drive circuit 8.
A recording signal is applied to the drive circuit 8 via the changeover switch 16, and the semiconductor laser 10 produces a strong laser light output pm at bit "1" of the recording signal, and a weak laser light output at bit rOJ. Produces Pb.

In addition to the configuration of such a magneto-optical disk device, in order to apply the recording method of the present invention, a ROM 1 for storing a standard data table, a RAM 15 for storing an actual data table,
A computer 4 for optimally controlling the laser light output during recording, a pm D/A converter 6 for converting the strong optimum laser light output pm given from the computer 4 into an analog signal, and a weak optimum laser light output Pb into an analog signal. A converter 7 for converting PB, a temperature sensor 2 that detects the operating environment temperature, and an A/A converter that converts the detected analog signal of the temperature sensor 2 into a digital signal and outputs it to the computer 4.
Drive circuit 8 via D converter 3 and changeover switch 16
A test signal generator 9 supplies a test signal to the magneto-optical disk 12, a light receiving element 13 receives the reproduced signal obtained from the optical head 5 during reproduction of the test signal recorded on the magneto-optical disk 12, and a secondary signal is generated from the light receiving output of the light receiving element 13. Secondary distortion detection circuit 1 that detects
4 are provided.

Regarding a magneto-optical disk device to which such a recording method of the present invention is applied, a method for creating a standard data table stored in the ROM 1 will be described first.

FIG. 2 is a flow diagram showing the process of creating a standard data table used in the present invention.

That is, the standard data table is created using a standard disk prepared in advance and a standard magneto-optical disk device.

First, as shown in step S1 in FIG. 2, at an arbitrary environmental temperature T1, for example, T=25.degree. C., the optimum laser light output at each disk radius is measured for a number of locations on a standard disk with different disk radii.

For example, the disk radius rl = 7cm at two locations, r2
-14cm, and each disk radius r1. The head is positioned at position Pr1.r2 and the optimum laser light output Pr1. Measure Pr2. This optimum laser light output pr1. The measurement of pr2 is based on a recording signal consisting of a predetermined bit configuration, for example, repeating "10", and a strong laser light output pm is determined at bit "1".
On the other hand, when bit "0" is irradiated with a weak laser light output Pb, the magnetization direction remains the same as the magnetization direction at the time of erasing, and after recording such a test signal, a weak laser light is applied. The recorded signal is reproduced by irradiation, and the laser light output Pm when there are no secondary particles included in the reproduced signal is determined as the optimum laser light output pr1. Measure as pr2.

The disk radii rl, r in such step S1
By measuring the optimum laser light outputs prl and pr2 for 2, the relationship between the disk radius and the optimum laser light output at an environmental temperature T=25°C is determined as shown in step S2, and the characteristic graph shown in FIG. 3 is obtained.

Once the relationship between the disk radius and the optimum laser light output at a specific usage environment temperature T=25° C. is determined in step S2, the disk radius rl is then determined as shown in step S3.
, r2, the optimum laser light output Pr is measured by changing the operating environment temperature T, and the relationship between the two is determined. As a result, for example, as shown in FIG. 4, the disk radius r1=7c
The relationship between the optimum laser light output Pr and the operating environment temperature T is obtained for m and disk radius r2=14 cm.

Subsequently, as shown in step S4, the third . From the characteristic graph of FIG. 4, the relationship between the disk radius r and the optimum laser light output Pr is determined using the operating environment temperature T as a parameter.

The relationship in step S4 is as shown in the graph of FIG. 5, for example. Specifically, for each of the characteristic curves for disk radius r1 = 7 cm and disk radius r2 = 14 cm shown in Fig. 4, the operating environment temperature T = 12.5.1.
7.5. ...The optimum laser light output at each temperature of 42.5°C is extracted and plotted as shown in Fig. 5, and the characteristics shown in Fig. 5 are obtained as a straight line connecting the two points of disk radius r1 and r2 at the same usage environment temperature. You can get a graph.

Note that the applicable environmental temperature in this case is 10°C to 45°C.

In step S4, if the relationship between the disk radius r and the optimum laser light output Pr is obtained with the environmental temperature T as a parameter shown in FIG. By specifying a two-dimensional address (r, T) consisting of temperature T, a standard data table can be created by obtaining the value of the corresponding optimum laser light output pr obtained from the characteristic graph of FIG. 5 and inputting it. Specifically, the optimum laser light output pr is stored in a memory address with the disk radius as the upper bit and the operating environment temperature as the lower bit.

Once ROM1 storing the standard data table created according to the processing flow shown in FIG. 2 has been created, the 6th
The actual recording operation in the magneto-optical disk device is performed according to the operational flow shown in the figure.

The processing of steps 81 to 316 in FIG. 6 is executed by the RAM in FIG.
15, this actual data table creation process is a preliminary recording and reproducing operation prior to the actual recording and reproducing operation, that is, recording and reproducing using the test signal from the test signal generator 9. produced by action.

That is, when the selector switch 16 in FIG. 1 is switched to the test signal generator 9 side to set the kitten mode, the computer 4 starts processing for creating an actual data table for the RAM 15.

First, as shown in step S1 in FIG. 6A, the operating environment temperature Tf detected by the temperature sensor 2 is converted into a digital signal by the A/D converter 3 and read into the computer 4 as T=Ti.

Subsequently, in step S2, a plurality of disk radial positions for obtaining the optimum laser light output are specified to the computer 4.

For example, specify the disk radii rl and r2. This disk radius r1. Upon receiving the designation of r2, the computer 4 creates a two-dimensional address (rl) based on the operating environment temperature Ti at that time.
, Ti) and (r2.Ti), the corresponding optimum laser light outputs Pr1 and Pr2 are read from the ROMI standard data table.

Subsequently, in step S3, the optical head 5 is first moved to the position of the disk radius r1, and in the next step S4, the optical head 5 is moved to the position of the disk radius r1.
The optimal laser light output Prl obtained in step 1 is set as a strong laser light output pm, and a test signal from the test signal generator 9 is recorded on a track of disk radius r by the optical head 5 under the control of the semiconductor laser 10 by the drive circuit 8.

In addition, the weak optimum laser light output Pb corresponding to the bit rOJ
, the drive circuit 8 adjusts P so as to maintain a constant laser light output based on the environmental temperature Ti detected by the temperature sensor 2.
It is controlled in response to the output of the D/A converter 7 for b. When the recording on the track of the disk radius r1 of the magneto-optical disk 12 based on the optimum laser light output Pr1 is completed in this way, the apparatus is switched to the reproduction mode and the optical head 5
The reflected light obtained is converted into an electric signal by the light receiving element 13, and the second-order distortion is detected by the second-order distortion detection circuit 14 and outputted to the computer 4, and the second-order distortion is detected from the reproduced signal as shown in step S5. If not, it is assumed that the optimum laser light output is reached and the process proceeds to the next step S7. On the other hand, if second-order distortion is included, the process proceeds to step S6, where the laser light output pr1 is increased or decreased by a predetermined amount ΔP, and then step 34 is performed again.
．． At step 35, the process of determining whether or not the laser light output is optimal through recording and reproducing the test signal is repeated.

Here, the detection output from the second-order distortion detection circuit 14 is as follows.

(a) When the duty ratio of the reproduced signal is greater than 50% (
)(H).

(b) When the duty ratio of the reproduced signal is less than 50% (
)-IL).

(C) When the duty ratio of the reproduced signal is 50% (LL>
.

In the process of step S6, if the duty ratio of the reproduced signal is greater than 50%, a predetermined value of 6 is subtracted to lower the laser light output, so that the duty ratio of the reproduced signal becomes 50%.
%, a predetermined value ΔP is added to increase the laser light output.

When the optimum laser light output without secondary distortion with a duty ratio of 50% is determined in step S5, the next step S
In step 7, the laser light output P1 is determined as the optimum value for the disk radius r1 and the operating environment temperature Ti.

Subsequently, in step S8, the optical head 5 is moved to the disk radius r2.
Then, in step S2, a test signal is similarly recorded on the magneto-optical disk 12 using the optimum laser light output Pr2 obtained from the standard data table as the initial value, and whether or not second-order distortion can be obtained from the reproduced output is determined. In step S10, it is determined whether the value is the optimum value or not. If it is not the optimum value, the process proceeds to step S11, where a predetermined value ΔP is added or subtracted depending on the magnitude relationship with respect to the duty ratio of 50%, and until the optimum value is obtained, step 89 Repeat the steps 311 to 311.

When the optimum value for the disk radius r2 is obtained in step SIO, as shown in step 312, the disk radius r
2 and the laser light output P as the optimum value of the operating environment temperature Ti.
Determine 2.

Subsequently, in step 313, the relationship between the operating environment temperature T and the optimum laser light output at the disk radius r1 is determined using the ROMI standard data table. Fig. 7 shows the optimum laser light output for the operating environment temperature T determined for the disc radius rl = 7 cm in the processing of the tube S13, and the optimum laser light output in Fig. 8 is (Pm - P
b). The relationship shown in FIG. 7 in step S13 can be determined as follows.

That is, as shown in FIG. 9, the standard data table stored in the ROM 1 stores the standard characteristic of the optimum laser light output with respect to the operating environment temperature T at the disk radius rl=7cIIl. S
The operating lA ambient humidity temperature i determined in step 7, for example T i =
The optimum laser light output P1=3 mW at 25° C. is plotted. Note that the optimum laser light output P1 determined in step S7 is P1=Pm-Pb, where Pb=4mW
Then, the optimum laser light output at Ti=25°C is 3
It is plotted as point P with mW+4mW=7mW.

If the point P determined by the optimum laser first cuff mW at a specific usage environment temperature T i =25°C in such an actual magneto-optical disk device is given, then By drawing a characteristic curve, the relationship between the operating environment temperature T and the optimum laser light output at a disk radius rl=7 cm can be determined as a practical characteristic.

Specifically, the deviation ΔPS between the P point of the practical characteristics and the PO point of the standard characteristics when T i = 25°C is calculated, and each value stored in the area of the disk radius rl = 7 cm of the standard data table giving the standard characteristics is calculated. By subtracting the deviation ΔPS from the optimum value for each operating environment temperature, it is possible to obtain the numerical value of the optimum laser light output that provides the actual characteristics.

Referring again to FIG. 6A, in the next step S14, the disk radius r2 is determined using the same standard data table.
The relationship between the operating environment temperature T and the optimum laser light output is determined. Through the processing in step S14, for example, the relationship between the optimum laser light output and the operating environment temperature T at the disk radius r=14 cm in FIG. 8 can be determined.

That is, No. 7.8 obtained in steps 313 and 314
The characteristic graph shown in the figure corresponds to the characteristic relationship shown in FIG. 5, which was obtained for a standard disk, obtained for an actual device.

Next, the process proceeds to step S15, and the disk radius r is determined using the operating environment temperature T as a parameter based on the characteristic relationships shown in FIGS. 7 and 8 obtained in step S13 and step 314.
The relationship between and the optimum laser light output P is determined. That is, the 10th
The relationship shown in the figure is required.

Incidentally, the dotted line in FIG. 10 indicates the characteristics of the standard disk shown in FIG.

If the characteristics shown in FIG. 10 are obtained in step 515, the optimum laser light output corresponding to the disk radius r and the operating environment temperature Ti is determined for this FIG. 10, and the two-dimensional address (r, Ti> Corresponding laser light output P@RA
An actual data table can be created by writing to M15.

Regarding the operating environment temperature Ti when creating the actual data table in the RAM 15, the applicable temperature range 10 to 45°C is divided into 5° increments as shown in Figures 7 and 8, and the center temperature of each division is (representative temperature) is used as address data. As a result, for example, when the temperature detected by the temperature sensor 2 is between 25°C and 30°C, the address data is converted to the central representative temperature of 27.5°C.
It will be used for AM15 addressing.

Once the actual data table has been created in the RAM 15 in this way, as shown in steps 81 to S16 in FIG. 6A, the process proceeds to FIG. 6B.

In the process shown in FIG. 6B, first, in step S17, it is checked whether or not disc recording has ended. If disc recording has not ended, the selector switch 16 in the embodiment shown in FIG. 1 is switched to the recording signal side. , steps 818-3
21 is performed.

That is, first, in step 318, the operating environment temperature Ti is measured by the temperature sensor 2, then in step S19, the disk radius ri where the optical head 5 is located is detected, and in step 320, the two-dimensional address (ri, l'- i) refers to the actual data table in the RAM 15 and extracts the corresponding optimum laser light output Pi.

Next, in step 321, when the recording signal bit is "1", the optimum laser light output P obtained by subtracting 1q from the actual data table is calculated.
The drive circuit 8 controls the drive current of the semiconductor laser 10 so that the optical head 5 performs recording and writes signals onto the magneto-optical disk 12, and the above process continues until the end of disk recording is determined in step S17. Repeat the process.

In the embodiment shown in FIG. 1, the RAM 15 is used as a storage means for the actual data table, so when the power of the device is turned off, the actual data table created through preliminary recording and reproduction is erased. However, by maintaining the recorded contents of RAM 15 with power supplied by the built-in battery, 1
Once the actual data table has been created, the optimum laser light output may be controlled using the same actual data table the next time it is used.

Of course, when used for a certain period of time, the operating characteristics of the semiconductor disk 10 will change over time, so in that case, the RAM
It is sufficient to delete the 15 actual data tables and create a new actual data table through preliminary recording and reproduction.

[Effects of the Invention] As explained above, according to the present invention, during recording, an actual data table created in advance based on a standard data table is used as a two-dimensional address based on the disk radius determined by the operating environment temperature and the head position at that time. It can be read out and controlled to the optimum value according to the specification, and there is no need for arithmetic processing to obtain the optimum laser light output each time, so processing time can be significantly shortened, and the burden of control processing on the computer is also reduced. , it is possible to repeat many processing cycles to obtain the optimum laser light output, and as a result, it is possible to finely adjust the laser light output, and it is possible to reliably record data without secondary particles.

[Brief explanation of the drawing]

Figure 1 is a block diagram of a magneto-optical disk device to which the recording method of the present invention is applied, Figure 2 is a flow diagram showing the process of creating a standard data table used in the present invention, and Figure 3 is a block diagram of a magneto-optical disk device to which the recording method of the present invention is applied. Fig. 4 is a characteristic graph of the operating environment temperature and optimum laser output obtained from a standard disc, and Fig. 5 is a characteristic graph of the operating environment temperature obtained for creating a standard data table. A characteristic graph of the disk radius as a parameter and the optimum laser light output, Fig. 6A is a flow diagram showing the process of creating an actual data table in the embodiment of Fig. 1, and Fig. 6B shows the optimum laser light output based on the actual data table. Fig. 7 is a characteristic graph of the operating environment temperature and optimum laser light output at radius r = 7 cm when creating the actual data table, and Fig. 8 is the characteristic graph for creating the actual data table. Characteristic graph of operating environment temperature and optimum laser light output at disk radius r2 = 14 cm. Figure 9 is a characteristic graph showing the principle of creating the characteristics of Figure 7 from a standard data table. Figure 10 is a graph of creating an actual data table. A characteristic graph showing the relationship between the disk radius and the optimum laser light output using the operating environment temperature as a parameter, Fig. 11 is an explanatory diagram of the conventional recording laser light output, and Fig. 12 shows the inner and outer tracks relative to the reference track. FIG. 3 is an explanatory diagram showing the duty ratio of each reproduced signal. 1: ROM (standard data table) 2: Temperature sensor 3: A/D converter 4: Computer 5: Optical head 6: Pm D-A converter 7: Pb D-A converter 8: Drive circuit 9: Test signal generation Device 10: Semiconductor laser 11 Spindle motor 12: Magneto-optical disk 13: Light receiving element 14: Secondary distortion detection circuit 15: RAM (actual data table) 15: Changeover switch Patent applicant Nippon Kogaku Kogyo Co., Ltd.

Claims (1)

[Claims] In a magneto-optical disk that can be repeatedly recorded, the value of the optimum laser light output obtained using a standard magneto-optical disk device is calculated using a two-dimensional address of the disk radius and operating environment temperature. It has a standard data table stored according to specifications, and initializes the corresponding optimum laser light output obtained from the standard data table for multiple locations at different radial positions of the magneto-optical disk through preliminary recording and reproducing at a certain environmental usage temperature. Measure the actual optimum laser light output as a value, determine the optimum laser light output value in the actual device based on the actual optimum laser light output, disk radius, operating environment temperature, and the stored value of the standard data table, An actual data table is created in which the output value is stored by specifying a two-dimensional address of the disk radius and operating environment temperature, and after the actual data table is created, it is stored according to the disk radius corresponding to the operating environment temperature and head position at that time. A method for recording a magneto-optical disk, characterized in that the intensity of a recording laser beam is controlled by reading the value of the optimum laser light output from the actual data table using a two-dimensional address.