JPH08297874A - Magneto-optical disk device - Google Patents

Abstract

PURPOSE: To optimize recording power at the time of recording a magneto- optical disk as a recording medium. CONSTITUTION: Prior to a regular recording operation, recording of a prescribed number of blocks is performed while a recording power value is stepwise changed by a light beam power control means 11 in a test area on the recording medium, and a reproducing operation is performed by a recorded information reproducing means 12, and then an occurrent frequency of the number of blocks to become verification errors is detected by an information quality checking means 13. By this method, recording power of writing information is detected, and a characteristic of recording sensitivity is inferred from this write-out recording power by a light beam power value calculating means 14, and optimum recording power is calculated and then the regular recording operation is carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical disk device, and more particularly to a magneto-optical disk device which irradiates a recording medium with a light beam to record and reproduce information.

[0002]

2. Description of the Related Art In a conventional magneto-optical disk device, when information is recorded on a recording medium, the recording operation is performed by irradiating a light beam having a power value preset according to the type of the device and the medium. .

Further, as a conventional publicly known example for calibrating the recording power, Japanese Patent Application Laid-Open No. 3-40236 is known.

The optical recording / reproducing apparatus disclosed in Japanese Unexamined Patent Publication No. 3-40236 detects means for controlling the light emission power of a laser beam applied to a recording medium and a recording position where recording is performed on the recording medium during a recording operation. Position detection means for outputting a recording position signal and a photodetector for receiving the reproduction signal light reflected from the recording medium during the reproduction operation, and the absolute values of the positive and negative peak values of the reproduction signal output from the photodetector. Peak difference detection means for detecting the peak difference, which is the difference, and peak difference detection means obtained by reproducing the recording recorded on the recording medium with a plurality of levels of emission power. And a means for obtaining an optimum recording power, and requires a dedicated and complicated circuit for calibrating the recording power.

[0005]

In the above-mentioned conventional magneto-optical disk apparatus for irradiating with a light beam having a preset power value for recording, a change in ambient temperature, contamination of the light beam condensing lens, The optimum power value required for recording changes due to changes in recording sensitivity due to dirt on the surface of the recording medium, and variations in recording sensitivity of the device and the medium itself. When information is recorded on the recording medium by irradiation, if the preset power value is used as it is, it is possible to stably store the recording magnetization state and reproduce the recorded information on the recording medium. There is a possibility that the optimum recording magnetization state cannot be formed, a phenomenon such as a recording failure appears, and the reliability of the device is lowered.

Further, the apparatus for performing the recording power calibration, such as Japanese Patent Laid-Open No. 3-40236, requires a complicated dedicated circuit for the recording power calibration, which causes a problem that the apparatus becomes expensive.

[0007]

A magneto-optical disk apparatus of the present invention is a magneto-optical disk apparatus for recording information by irradiating a recording medium with a light beam to form a recording magnetization state on the recording medium. Therefore, the light beam power value control means for controlling the power value of the light beam, the recording information reproducing means for reproducing the recorded information from the recording medium, and the information quality of the information reproduced by the recording information reproducing means are checked. Before the normal recording operation, the information quality checking means and the light beam power value calculating means for calculating the optimum light beam power value for recording information in the optimum recording magnetization state on the recording medium are provided. In addition, the light beam power value control means performs recording while gradually changing the light beam power value at the time of recording, and the information reproduced by the recorded information reproducing means is recorded in the information quality checking means. Therefore verified, it calculates the optimum light beam power value by the light beam power value calculating means, then and performing normal recording operation.

[0008]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the magneto-optical disk device of the present invention, FIG. 2 is a flow chart for explaining the operation of the magneto-optical disk device of FIG. 1, and FIG. 3 is the magneto-optical disk device of FIG. 6 is a diagram showing the relationship between the recording power and recording quality of FIG.

In FIG. 1, the magneto-optical disk apparatus of this embodiment comprises a light beam power value control means 11 for controlling the power value of a light beam, and a recorded information reproduction means 12 for reproducing recorded information on a recording medium. , An information quality checking means 13 for checking the information quality of the information reproduced by the recording information reproducing means 12, and an optimum light beam power value for recording the information on the recording medium in the optimum recording magnetization state. And a light beam power value calculating means 14 for

Next, the operation of the magneto-optical disk device of this embodiment will be described with reference to the drawings.

In FIG. 2, first, the test area is sought (step 101), the recording power is set by the light beam power value control means 11 in FIG. 1 (step 102), the information is recorded, and the recorded information reproducing means 12 is used. The information is reproduced (step 103). Then, the information quality check means 1
The quality of the reproduced signal is judged by 3 (step 104),
The write recording power is detected (step 105). If the write-out recording power is not detected (step 105, N
o), the recording power value is changed (step 8), and the process returns to the recording power setting in step 102. When the write-out recording power is detected (step 105, Yes), the recording sensitivity is estimated by the light beam power value calculating means 14 to determine the recording power (steps 106 and 107), and the process is ended.

Next, details of the recording power determination process will be described with reference to the drawings.

In FIG. 3, 1. Pmax ... Maximum recording power set in advance (maximum emission power allowed by the device) 2. Pmin ... A preset minimum recording power (normally, it is considered that normal recording operation cannot be performed below this value). Pdef: preset recording power (normally, at this power, there is a margin for power fluctuation, and it is considered that normal recording is possible) 4. Pmat ... Recording power selected by recording power calibration 5. Pad ... Power margin below added power 1 (value for power calibration) 6. Pad …… Additional power 1 (value for power calibration) Upper power margin 7. Puni ... Change value when changing the recording power value 8. Num …… Number of recording blocks at recording power calibration 9. Num ... Threshold value of verification error number at recording power calibration Here, the vertical axis of FIG. 3 indicates that the recording sensitivity is higher toward the upper side, and the value is lower than the recording power on the horizontal axis. It indicates that the recording is being done.

When a recording command is issued from the upper device side, the recording power is optimized by performing the following recording / reproducing operation in the test area on the recording medium before performing the normal recording operation.

The recording power is decreased from the recording power value Pdef3 by the unit power value Puni7 by a prescribed number of blocks Nu.
The recording / reproducing operation of m8 is performed (step 102 to FIG. 2).
104, 105 YES, 108). At this time, the number of blocks causing a verify error by performing the verify operation that is performed during the normal recording operation as the reproducing operation is the specified value Num.
A recording power value exceeding 9 is detected (step 10 in FIG. 2).
5 YES), the power value obtained by adding the unit power Puni7 to the power value is regarded as the writing power, and the recording sensitivity is estimated. The minimum necessary value for performing this recording, that is, the value obtained by adding Pad5 to the write recording power is assumed to be the proper recording power, and the specified number of blocks Num8 is used for the recording operation with the value obtained by adding Pad6 to this power value. , Specified value Num is the block that causes verification error
Confirm that it does not exceed 9 and check that the appropriate recording power Pma
It is determined to be t4 (steps 106 and 107 in FIG. 2). By a series of these operations, it is possible to obtain a value which is considered to be optimum in terms of recording sensitivity and has a recording power margin of at least Pad5 on the lower side and Pad6 on the upper side.

If the number of verify error blocks does not exceed the specified value Num8 even if the number of verify error blocks is reduced to Pmin2,
The recording sensitivity is estimated by regarding Pmin2 as the write recording power, and the same operation is performed assuming that the value obtained by adding Pad5 to Pmin2 is the appropriate recording power. Or Pm
The recording power is further reduced to in2 or less, and the recording and reproducing operations are performed, and the recording power value in which the number of blocks causing the verification error exceeds the specified value Num9 is detected, and the recording sensitivity is estimated in the same manner as described above to determine the appropriate recording power value. To calculate.

When the number of verify errors exceeds the specified value Num2 at the start recording power Pdef3, the recording power is decreased by the unit power Puni7 to perform the recording / reproducing operation, and the recording power whose verify error number is below the specified value Num9 is detected. Further, the recording power is lowered to perform the recording / reproducing operation, the recording power in which the number of verify errors exceeds the specified value Num9 is detected, and the same operation as the above operation is performed to calculate the appropriate power value.

Next, if the verify error exceeds the specified value Num9 for all of Pdef3 to Pmin2, the recording power is increased by the unit power value Puni7 from the recording power value Pdef3 to perform the recording / reproducing operation, and the number of blocks causing the verify error. Is detected as a recording power value below the specified value Num9, that is, the write recording power value is detected, and Pad5 is added to the recording power value to assume the appropriate recording power, and a value obtained by adding Pad6 to this recording power value is a specified number of blocks. The recording operation of several Num8 is performed, and it is determined that the block having the verify error does not exceed the specified value Num9, and the proper recording power Pmat4 is determined.

When Pmat ≧ Pmax is calculated as a result of the above recording power calibration, the margin is reduced and Pmat = Pmax is set to terminate the calibration, or it is determined that the sensitivity is abnormal and the calibration is terminated. Select one.

As described above, the recording power is optimized by using only the existing device configuration.

FIG. 4 is a diagram showing the recording sensitivity characteristic of the relationship between the recording power and the recording amplitude at the minimum recording frequency and the maximum recording frequency of the magneto-optical disk device of FIG. 1, and the recording power Pmin1, Pdef3, Pmax1 in the recording sensitivity characteristic.
Is the setting value of.

The recording power is calibrated as described above in order to cope with this variation in recording sensitivity.

As described above, the optimum recording power can be calibrated easily and inexpensively by using the existing circuit configuration for judging the quality of the recording state.

[0025]

As described above, in the magneto-optical disk apparatus of the present invention, when recording information on the recording medium, the recording operation is performed by selecting the optimum light beam power value and performing the recording operation. There is an effect that a recording magnetization state in which the state can be stored and the recorded information can be reproduced stably can be obtained and the reliability of the apparatus can be improved.

Further, in the magneto-optical disk device of the present invention,
When deciding the quality of the recording state and calibrating the recording power, there is an effect that the existing circuit configuration can be used to easily and inexpensively calibrate the optimum recording power.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a magneto-optical disk device of the present invention.

FIG. 2 is a flow chart for explaining the operation of the magneto-optical disk device of FIG.

FIG. 3 is a diagram showing a relationship between recording power and recording quality of the magneto-optical disk device of FIG.

4 is a diagram showing the recording sensitivity characteristic of the relationship between the recording power and the recording amplitude at the minimum recording frequency and the maximum recording frequency of the magneto-optical disk device of FIG.

[Explanation of symbols]

 1 Pmax 2 Pmin 3 Pdef 4 Pmat 5 Pad 6 Pad 7 Puni 8 Num 9 Num 11 Light beam power value control means 12 Recording information reproducing means 13 Information quality checking means 14 Light beam power value calculating means

Claims (1)

[Claims] 1. A magneto-optical disk device for recording information by irradiating a recording medium with a light beam and forming a recording magnetization state on the recording medium, wherein the power value of the light beam is controlled. Optical beam power value control means, recording information reproducing means for reproducing recording information from the recording medium, information quality checking means for checking information quality of information reproduced by the recording information reproducing means, and the recording medium And a light beam power value calculating means for calculating a light beam power value optimum for recording information in the optimum recording magnetization state, and controlling the light beam power value before starting a normal recording operation. Recording is performed while gradually changing the light beam power value at the time of recording by means, and the information reproduced by the recorded information reproducing means is verified by the information quality checking means. A magneto-optical disk device characterized in that an optimum light beam power value is calculated by the light beam power value calculating means, and then a normal recording operation is performed.