JP2853364B2 - Magneto-optical disk drive - Google Patents

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 drive, and more particularly to a magneto-optical disk drive for setting the intensity of a recording laser beam of a recordable magneto-optical disk in accordance with the recording radius of the disk and the operating temperature. And a technique for removing an adverse effect such as a transient response due to a change in the set value of the intensity of the recording laser light.

[Prior art]

2. Description of the Related Art In a magneto-optical disk device, for example, as disclosed in Japanese Patent Application Laid-Open No. 1-112551, the output of a recording laser beam is controlled in accordance with the recording radius of a disk and the ambient temperature of use. In such a magneto-optical disk device, a data table in which an optimum laser beam output value is recorded corresponding to a two-dimensional address of a disk radius and a use environment temperature is used, and there is a change in a recording radius and a use environment temperature. The set value of the light emission output of the laser diode was changed immediately. Further, the laser diode drive circuit has performed closed loop control so as to emit light according to such a set value.

[0003]

However, in the above-described conventional magneto-optical disk drive, if there is a change in the recording radius or the use environment temperature, the light emission output of the laser diode is reduced even during data recording. Due to the change, the light emission output of the laser diode causes a so-called step response during data recording in combination with the closed loop control of the laser diode drive circuit. For this reason, the signal recorded during the transient response section of the output of the laser diode is not recorded with the laser light output according to the set value, deteriorating the signal quality and causing the error rate to deteriorate.

SUMMARY OF THE INVENTION In view of the above-mentioned problems in the prior art apparatus, it is an object of the present invention to prevent the quality of recording data from deteriorating due to a transient response occurring when the set value of the light emitting output of a laser diode is changed. It is an object of the present invention to provide a magneto-optical disk drive capable of performing data recording with the same laser light output.

[0005]

According to the present invention, there is provided a recordable magneto-optical disk for controlling an output of a recording laser beam in accordance with a radial position of the magneto-optical disk and an ambient temperature of use. An apparatus for outputting a signal indicating an ID section in a recording track of the magneto-optical disk, wherein a setting value of an output of the recording laser light is provided.
According to the radial position of the magneto-optical disk and the operating temperature
The change is performed while the signal indicating the ID section is being output.

[0006]

In the magneto-optical disk device according to the above configuration, when the recording radius of the magneto-optical disk or the use environment temperature changes, the signal indicating the ID section is referred to,
In the section D, the setting value of the output of the recording laser light is changed immediately, but in the section other than the ID section, the setting value of the output of the recording laser light is not changed immediately. In this case, the change of the set value of the output of the recording laser light is performed in the next ID section, avoiding the data recording period. Since data is not recorded in the ID section,
Even if the set value of the output of the recording laser beam is changed, no inconvenience occurs. Further, since the set value of the output of the recording laser light is not changed during the data recording period,
Deterioration of the data recording quality due to the transient response of the laser light output is accurately prevented.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a magneto-optical disk drive according to one embodiment of the present invention. In FIG. 1, reference numeral 12 denotes a magneto-optical disk, which is set on a rotating shaft of a spindle motor 11 and is rotated at a constant angular speed, for example, at a constant speed of 3600 rpm. An optical head 5 is provided at a position facing the recording surface of the magneto-optical disk 12 so as to be movable in the radial direction. The optical head 5 irradiates a laser beam from the semiconductor laser 10 to irradiate a beam spot on the recording surface. To erase, record or reproduce. The intensity of the laser light output from the semiconductor laser 10 is controlled by a drive circuit 8, a recording signal is applied to the drive circuit 8 via a changeover switch 16, and the semiconductor laser 10 is driven by a bit “1” of the recording signal. A strong laser light output Pm is generated, and a weak laser light output Pb is generated at bit “0”.

In addition to the configuration of such a magneto-optical disk device, a ROM 1 for storing a standard data table for determining a laser beam output, and an RA for storing an actual data table.
M15, a computer 4 for optimally controlling the laser beam output at the time of recording, a D / D for Pm for converting the strong optimal laser beam output Pm given from the computer 4 into an analog signal
An A converter and a Pb D / A converter 7 for converting the weak optimum laser light output Pb into an analog signal are provided. Further, the apparatus shown in FIG. 1 includes a temperature sensor 2 for detecting a use environment temperature, an A / A converter for converting an analog signal detected by the temperature sensor 2 into a digital signal and outputting the digital signal to a computer 4.
Drive circuit 8 via D converter 3 and changeover switch 16
A test signal generator 9 for supplying a test signal to the optical disk 12, a light receiving element 13 for receiving a reproduced signal obtained from the optical head 5 in recording and reproducing the test signal on and from the magneto-optical disk 12, Secondary distortion detection circuit 1 for detecting distortion
4 is provided.

The computer 4 also receives an ID section detection signal and a disk radius position detection signal.
The ID section detection signal can be easily obtained from a data section detection gate pulse or an ID section detection gate pulse when a recording signal to be applied to the changeover switch 16 is created. The disk radial position detection signal can be obtained by a known method by using a linear scale (not shown) for detecting the position of the optical head 5 in the radial direction.

FIG. 2 shows an ISO format as an example of a sector format of a 5 inch magneto-optical disk. In the format shown in the figure, one track is divided into 17 sectors, and each sector has a recording capacity of 1360 bytes. The first 52 bytes of the 1360 bytes are the sector mark SM and the ID.
Section, which is pre-formatted,
This part is not used for recording data. The sector mark SM (5 bytes) is a mark indicating the head of a sector, and has another section (VFO1 to BUFFER in FIG. 2).
It consists of unique patterns that do not appear in. The magneto-optical disk device usually has a gate pulse for distinguishing this ID section from other data recording sections. The gate pulse is triggered by a detection signal generated by detecting the sector mark SM. The gate pulse continues to be generated while counting 47 bytes (the length of the ID section). This gate pulse is used for generating the ID section detection signal shown in FIG. The ID section detection signal is, for example, a signal having a high level (H) in an ID section and a low level (L) in other sections, and is supplied to the computer 4 in FIG. 1 as described above.

In the magneto-optical disk drive having the above-described configuration, when data is recorded, similar to the apparatus described in Japanese Patent Application Laid-Open No. 1-112551,
An actual data table is created based on a standard data table stored in the ROM 1 and indicating the relationship between the optimum laser light output corresponding to the use environment temperature and the radial position. That is,
To create the actual data table, a signal from the test signal generator 9 is supplied to the drive circuit 8 via the changeover switch 16, and the semiconductor laser 10 is driven and recorded on the magneto-optical disk 12. Then, the test signal is transmitted to the optical head 5 and the light receiving element 13.
Through the computer, the secondary distortion is detected, and the computer 4
To enter. The computer 4 obtains an optimum laser light output that minimizes the secondary distortion, stores the output value in the RAM 15 in correspondence with the two-dimensional address of the disk radius and the use environment temperature, and creates and stores an actual data table. .

After the actual data table is created in this manner, when recording signals actually input via the changeover switch 16 are to be recorded, the operating environment temperature and the disk radius detected by the temperature sensor 2 are recorded. Based on the position detection signal, a corresponding optimum laser light output value is read from the actual data table in the RAM 15.

The computer 4 retrieves the intensity of the recording laser beam corresponding to the disk radial position and the operating environment temperature from the temperature sensor 2 in this manner, and stores the data "1" in each of the D / A converters 6 and 7. Driving signals corresponding to "" and "0" are input, and these driving signals are applied to the driving circuit 8 via the respective D / A converters 6 and 7. The drive circuit 8 selects one of the signals from the D / A converters 6 and 7 according to the value “1” or “0” of the recording signal, and drives the semiconductor laser 10 according to this signal. In this way, recording is performed with the optimum laser light output according to the use environment temperature and the disk radial position.

In such an operation, the computer 4
When there is a change between the use environment temperature data input from the temperature sensor 2 and the disk radius position detection signal, first, the ID section detection signal is referred to, and there is a change in the above two signals outside the ID section. Also, the set value of the laser light output is not changed. Then, when it is detected from the ID section detection signal that the disc has entered the ID section, the RAM 15 is used in response to the disk radial position signal and the use environment temperature signal input from the temperature sensor 2 via the A / D converter 3. Is updated, ie, the address of the actual data table stored in the. As a result, the updated set value of the laser light output is output to each of the D / A converters 6 and 7 for the first time after entering the I / D section. Thereby, the set value of the laser beam output does not fluctuate during data recording.

FIG. 3 shows a schematic configuration of a magneto-optical disk drive according to a second embodiment of the present invention. In the apparatus shown in FIG. 1, a data holding circuit 17 is connected to the output of the computer 4 in the apparatus shown in FIG. 1, and the set value of the output of the recording laser light is transmitted via the data holding circuit 17 to each D / A converter 6 and 7 is supplied. The ID section detection signal input to the computer 4 in the embodiment of FIG. 1 is input to the data holding circuit 17 in the second embodiment of FIG.
Indicates that the input data is retained in areas other than the ID section, and the input data is passed to the output only in the ID section. Other parts are similar to those of the embodiment of FIG. 1 and are indicated by the same reference numerals.

In the apparatus shown in FIG. 3, during data recording, the computer 4 changes the disk radial position and / or the use environment temperature based on the disc radius position detection signal and the signal indicating the use environment temperature from the temperature sensor 2. The data table recorded in the RAM 15 is immediately searched, and a new set value of the laser beam output is read and input to the data holding circuit 17. The data holding circuit 17 allows the input data to pass through the output in the ID section as described above,
Data other than the ID section is held until the next ID section.
Therefore, the set value of the laser beam output input to the data holding circuit 17 is immediately supplied to each of the D / A converters 6 and 7 in the ID section, and is held until the next ID section in other than the ID section, and then held in each D / A converter. It is supplied to converters 6 and 7.
As a result, during data recording, the disc radial position and / or
Alternatively, the set value of the laser light output does not change even when the use environment temperature changes, and the laser light output does not change during data recording.

[0017]

As described above, according to the present invention, the set value of the recording laser light output corresponding to the change in the radial position of the disk and / or the change in the use environment temperature is changed only in the ID section, and the data recording is performed. The laser beam output does not fluctuate during data recording. Therefore, there is no deterioration in signal quality due to a transient response or the like, and data recording is performed with the laser beam output as set. Therefore, a reduction in the error rate of the recorded data is properly prevented, and a highly reliable magneto-optical disk device can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a magneto-optical disk device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a signal recording format used in a magneto-optical disk device according to the present invention.

FIG. 3 is a block diagram showing a schematic configuration of a magneto-optical disk device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ROM 2 Temperature sensor 3 A / D converter 4 Computer 5 Optical head 6, 7 D / A converter 8 Drive circuit 9 Test signal generator 10 Semiconductor laser 11 Spindle motor 12 Magneto-optical disk 13 Light receiving element 14 Secondary distortion detection circuit 15 RAM 16 selector switch 17 data holding circuit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) G11B 7/00 G11B 7/125 G11B 11/10 551 G11B 11/10 586

Claims (1)

(57) [Claims] 1. A recordable magneto-optical disk device for controlling the output of a recording laser beam in accordance with a radial position of a magneto-optical disk and a use environment temperature, and shows an ID section in a recording track of the magneto-optical disk. Means for outputting a signal, wherein the set value of the output of the recording laser light is a radial position of the magneto-optical disk and a working ring.
Magneto-optical Di, characterized in that performing during the signal changes according to boundary temperature indicating the ID section is output
Disk device .