JPH0612722A - Magneto-optical recorder - Google Patents

Abstract

PURPOSE:To prevent the reduction in the reliability of a regenerative signal for a verification caused by the leakage of an original signal by providing a gain adjusting means and a recording means for recording the gain obtained by the gain adjusting means. CONSTITUTION:A controller 324 repeatedly adjusts a gain until the output values of regenerative signal level detectors 311 and 315 are settled in an allowable region against a prescribed reference value. At this time, the setting values of voltage control amplifiers 307 and 309 are stored in a first and a second addresses of data E<2>PROM 325. In the next step, signals are beforehand recorded in order to detect the amount of leakage of the original signal and the gain is adjusted so as to detect the amount of leakage of the original signal when the signals are erased and to minimize it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical recording apparatus for recording information by the interaction of light and magnetism, and more particularly to a magneto-optical recording apparatus capable of simultaneously recording and verifying with one light beam.

[0002]

2. Description of the Related Art In recent years, a magneto-optical recording device as a large-capacity external memory has been actively developed along with the development of computer technology. Such a magneto-optical recording apparatus magnetically records information by utilizing a local temperature rise of a magnetic thin film due to spot irradiation of laser light, and reproduces information by utilizing a magneto-optical effect, particularly a Kerr effect. It has the feature that information can be erased and rewritten. However, in spite of having such an excellent advantage, in the process of recording information, three processes are required, such as erasing the already recorded old information, recording new information, and verifying the recorded information. There was a problem that the recording speed was slow.

Therefore, as a solution to such a problem, there is a direct verify in which verify is performed at the same time as recording, as proposed in Japanese Patent Laid-Open No. 3-73448. The direct verification will be described below with reference to FIG. In FIG. 7, 101
Is a disk-shaped magneto-optical recording medium, which is rotationally driven in a fixed direction while being held on the turntable 102. The laser light emitted from the laser light source 103 is collimated by the collimator lens 104, transmitted through the beam splitter 105, and then passed through the objective lens 106 to produce the magneto-optical medium 1.
Focused on 01. A magnetic field generating means 107 is arranged on the back side of the light beam irradiation portion with respect to the magneto-optical recording medium 101, and a magnetic field that changes according to information to be recorded, that is, an information modulating magnetic field is generated from this magnetic field generating means 107. . The information modulating magnetic field is applied to the magneto-optical recording medium 1
Information is recorded on the magneto-optical recording medium 101 by being applied to the light beam irradiation unit 01. At this time, the erasing operation of the old information in the recording area to be written is performed at the same time as the above recording operation. That is, the old information is erased simultaneously with recording by the magnetic field modulation type overwrite technology.

On the other hand, when the above-mentioned overwrite operation is performed, at the same time, the reflected light from the magneto-optical recording medium 101 is again guided to the beam splitter 105 through the objective lens 106. Then, the reflected light from the recording medium 1 is reflected by the beam splitter 105, and the half-wave plate 1
After passing 08, the polarization beam splitter 109
It is split into two light beams. One light beam is a convex lens 111,
After passing through the cylindrical lens 112, it is received by the four-division light receiving element 113. Each detection signal of the four-division light receiving element 113 is output to an autofocus / autotracking control circuit (not shown), and autofocus / autotracking control is performed based on this detection signal. The other light flux is received by the light receiving element 114 via the convex lens 110, and the total output of the four-divided light receiving element 113 and the light receiving element 1 are received.
By differentially detecting the output of 14, the recorded information is reproduced as a magneto-optical signal. That is, the recorded information is reproduced in real time, and the verification is performed using this reproduced signal. Therefore, in addition to the overwrite technique, the one-pass write operation of erasing, recording, and verifying once can be performed.

FIG. 8 shows the state of the light spot on the magneto-optical recording medium 101 on which recording is performed by the magnetic field modulation method and the magnetized state of the magneto-optical recording medium 101 during information recording. The arrow in the figure indicates the relative movement direction of the light spot with respect to the magneto-optical recording medium 101, and the circle at the right end represents the light spot. The crescent-shaped region indicated by diagonal lines in this light spot is a low-temperature region that has not been sufficiently heated yet, and the reversal of the magnetic field is indefinite depending on the recording medium. The above-described direct verify operation may not work for such a medium in some cases, and in order to solve this, a reproduction signal detection system shown in FIG. 9 has been proposed. In the conventional device shown in the same figure, two two-divided light receiving elements 131 and 13 for receiving a reflected light beam from a magneto-optical recording medium and detecting a magneto-optical signal.
Two are provided. That is, in each of the two-divided light receiving elements 131 and 132, the low temperature region in the shaded area where the reflected light flux from the magneto-optical recording medium is not sufficiently heated (see FIG. 8).
Element pieces 31a, 32 for receiving the reflected light flux corresponding to
a and element pieces 31b and 32b for receiving the reflected light flux corresponding to the high temperature region where heating is sufficiently performed. Then, the element pieces 31a, 32a, 31b, 3
Each output S ₆ from 2b, S _9, S _7, the reproducing magneto-optical signal on the basis of the _{S 8 (S 6 + S 7} ) - (S 8 + S 9) together is obtained, verifying light magnetic signal (S ₈ -S ₇ ) is obtained.

[0006]

However, in the above conventional device, the verify signal obtained from the light-receiving element pieces 31b and 32b is shaded even if a two-divided sensor as shown in FIG. 9 is used. It will inevitably include part of the low temperature region shown in. Therefore, the signal component in the low temperature region becomes a noise factor with respect to the verify signal, and it is difficult to accurately detect the verify signal. The leakage of the old signal into the verify signal is 2
When the drive device is manufactured, the degree of leakage of old signals from the individual drive devices will differ, and the quality of the verify signal will vary from drive device to drive device. There was a problem that it would occur.

The present invention has been made to solve the above problems, and its purpose is to obtain an accurate verify signal without requiring highly accurate sensor position adjustment. To provide a device.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to divide a light beam reflected from a magneto-optical recording medium into two light beams in a plane including the track direction, and detect the two light beams by a two-division light receiving element. In addition, in the magneto-optical recording device for generating a reproduction signal for verification by taking the signal difference between the respective two-divided light receiving elements, amplification for varying the signal level of each of the two-divided light receiving elements. Means, a gain adjusting means for adjusting the gain of each of the amplifying means to determine a gain that minimizes leakage of an old signal component into the two-divided light receiving element, and a gain obtained by the gain adjusting means. The present invention is achieved by a magneto-optical recording device, which is provided with a storage means for storing

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings. First, a configuration example of an optical system in the magneto-optical recording apparatus of the present invention will be described with reference to FIG. In FIG. 2, reference numeral 1 denotes a semiconductor laser provided as a recording light source. A divergent laser beam emitted from this semiconductor laser 1 is collimated by a collimator lens 2 and then enters a objective lens 4 through a compound prism 3. . Then, the laser light flux is focused by the objective lens 4 and imaged as a minute light spot on the magneto-optical recording medium 5. The light beam thus irradiated is reflected by the magneto-optical recording medium 5 and again passes through the objective lens 4 to enter the compound prism 3. Part of this reflected light flux is extracted from the cemented surface 3a of the compound prism 3, passes through the convex lens 7 and the cylindrical lens 8, and reaches the servo sensor 9. The detection signal of the servo sensor 9 is
It is output to the auto-tracking control circuit, and auto-focus and auto-tracking control are performed based on this signal. Further, when the light flux extracted from the cemented surface 3b of the composite prism 3 is transmitted through the Wollaston prism 10, it is separated into two light fluxes 13 and 14 composed of linearly polarized components which are orthogonal to each other, and then the convex lens 11 causes the RF sensor. 12 is focused. Here, the light flux of the semiconductor laser 1 is a linearly polarized light composed of a polarized component vibrating in the plane of the paper.

On the other hand, the Wollaston prism 10 comprises two cemented quartz prisms, and the optical axes of the quartz prisms are in the reference plane orthogonal to the parallel light flux extracted from the cemented surface 3b, and are orthogonal to each other. , One of them forms an angle of 45 ° with respect to the paper surface. Therefore, the light flux 13 is in the reference plane and is 45
If the linearly polarized light oscillates in a direction forming an angle of °, the light beam 14 becomes a linearly polarized light that oscillates in a direction forming an angle of 135 ° with the paper surface.
An optical head 30 is configured by integrating the above optical elements. In this embodiment, it is assumed that the magneto-optical recording medium 5 is moving in the arrow A direction on the paper surface with respect to the objective lens 4, and therefore the two light fluxes 13 and 14 are in the track direction (arrow A).
Is in the plane including (inside the paper). In addition, examples of a magneto-optical recording medium suitable for using the above optical system include an exchange-coupling type two-layer film structure. Further, reference numeral 6 in the figure denotes a magnetic head for generating a recording magnetic field.

FIG. 3 is a circuit diagram showing a signal detection circuit for detecting a reproduction signal based on the output signal of the RF sensor 12. The RF sensor 12 includes a first two-divided sensor 15 including light receiving portions 15a and 15b and light receiving portions 16a and 16b.
The second two-divided sensor 16 is composed of
The first and second two sets of the two-divided sensors 15 and 16 are each divided into two in the track direction, and the light flux 13 is divided into the divided light receiving portions 15.
The light beam 14 is arranged so as to enter the light receiving portions 16a and 16b, and the light beam 14 also enters the divided light receiving portions 16a and 16b. The light amount center of the light flux does not have to match the center of the split sensor. The signals of the respective light receiving portions 15a and 15b of the first two-divided sensor 15 are added by the adder 24 and then output to the differential amplifier 28, and the signals of the light receiving portions 16a and 16b of the second two-divided sensor are also added. After being added by the device 26, it is output to the differential amplifier 28. The differential amplifier 28 differentially detects the two added signals, and the obtained signal is used as the reproduction signal 17 at the normal time. On the other hand, the signals of the light receiving portions 15a and 15b of the first two-divided sensor 15 are adjusted in gain by the gain adjusting mechanisms 19 and 20, respectively, and then differentially detected by the differential amplifier 23. The signals of the light receiving portions 16a and 16b of the second two-divided sensor 16 are also differentially detected by the differential amplifier 25 after the gains thereof are adjusted by the gain adjusting mechanisms 21 and 22. The signals of the differential amplifiers 23 and 25 are further differentially detected by the differential amplifier 27, and the obtained signal becomes the verification reproduction signal 18 at the time of information recording. At the time of information recording, the verification reproduction signal 18 is reproduced at the same time as the information recording, and the obtained verification reproduction signal 18 is sent to a verification determination circuit (not shown). Then, by comparing the recorded data with the recorded data, the direct verification is performed at the same time as the recording. In the gain adjusting mechanisms 19, 20, 21, and 22, the gains are G1 and G1, respectively.
It is adjusted to G2, G3, and G4, and this adjustment operation will be described later in detail.

Next, the principle of gain adjustment when reproducing the verification reproduction signal 18 will be described. First, in the light spot 13 shown in FIG. 3, the ratio of the spot low temperature region leaking to the light receiving portion 15a is J, the ratio of the spot high temperature region leaking to the light receiving portion 15b is K, and similarly, spot 1
4, the ratio of the spot low temperature region leaking to the light receiving part 16a is L, and the ratio of the spot high temperature region leaking to the light receiving part 16b is M. For the sake of simplicity, the loss due to the dead zone of the two-divided sensor is ignored, and all output signals obtained from the high temperature region in the light spot 13 in the first two-divided sensor 15 are V1 and all output signals obtained from the low temperature region are R1, 15
The signal output of a is v1, and the signal output of 15b is r1.
Similarly, in the second two-divided sensor 16, all output signals obtained from the high temperature region in the light spot 14 are V2, all output signals obtained from the low temperature region are R2, 15a signal outputs are v2 and 15b signal outputs. Let r2 be the first 2
For the divided sensor 15, r1 = (1−J) R1 + K · V1 (1) v1 = J · R1 + (1−K) V1 (2) Regarding the second two-divided sensor 16, r2 = (1−L) R2 + M · V2 (3) v1 = L · R2 + (1−M) V2 (4) holds. When R1 is erased from the equations (1) and (2), it becomes V1 = ((1-J) v1-J · r1) / (1- (J + K)) (5). Similarly, when R2 is deleted from the equations (3) and (4), V1 = ((1-L) v1-L · r1) / (1- (L + M)) (6) is obtained. Therefore, if the above gains are set according to the equations (5) and (6) as follows: G1 = 1-J, G2 = J (7) G3 = 1-L, G4 = L (8) 23 difference signals (15a × G1-1
5b × G2) and the difference signal between the differential amplifier 25 (16a × G3)
It is possible to remove the leak signal from the low temperature region from −16b × G4).

The above is the principle explanation, but as described above, since the leak rate actually changes depending on the positional relationship between the sensor and the beam entering the sensor, it depends on the mounting accuracy of the sensor and the beam. The rate of leakage differs depending on the drive (device). Therefore, it is necessary to measure the degree of leakage for each drive and set the gains G1, G2, G3, and G4 to the gains corresponding to the values.

FIG. 1 is a block diagram showing the essential structure of a magneto-optical recording apparatus according to the present invention. That is, it is a block diagram showing an embodiment of a gain automatic adjustment circuit for automatically adjusting the gain according to the mounting position accuracy of the sensor and the beam. In FIG. 1, reference numerals 301 and 302 denote RF signal detecting two-division sensors attached to an optical head (not shown).
The configuration is as shown in FIG. 303-30
Reference numeral 6 is a low-noise current-voltage conversion amplifier with fixed conversion gain for converting the signal current detected by the RF sensors 301 and 302 into a voltage, and 307 and 310 are voltage controls connected to the current-voltage conversion amplifiers 303 to 306, respectively. Amplifier 311 is a signal level detector connected to this amplifier 307, 312 is a differential amplifier for taking the difference between the outputs of the amplifiers 307 and 308, and 313 is a signal level for detecting the output level of the differential amplifier 312. A detector 314 is a summing amplifier for adding the outputs of the amplifiers 307 and 308, a signal level detector 315 is for detecting the signal level of the output of the amplifier 309, and a reference numeral 316 is an amplifier 309, 3.
10 is a signal level detector for detecting the output level of the differential amplifier 316, 318 is a summing amplifier for obtaining the sum of the outputs of the amplifiers 309, 310. Is connected to the gain control inputs of the amplifiers 307 and 310, and is a 4-channel D / A for outputting a control voltage to the amplifiers by a signal from the drive controller 324 which controls the entire drive.
A converter, 320 is a differential amplifier for taking a difference between outputs of the differential amplifiers 312 and 316, and 321 is a summing amplifier 31.
A differential amplifier for taking the difference between the outputs of 4, 318, 322
Is an addition amplifier for adding the outputs of the addition amplifiers 314, 318, and 323 is a signal level detector 311, 313.
A four-channel A / D converter 325, which is connected to the outputs of 315 and 317, converts each signal level into a digital value and sends it to the drive controller 324, is connected to the CPU section in the drive controller 324, and the optical head An electrically rewritable E ² PROM 326 arranged on the unit is a check mode switch for turning the drive controller 324 into the check mode by turning it on.

The operation will now be described. First, the voltage control amplifiers 307 to 310 of FIG. 1 correspond to the gain adjusting mechanisms 19 to 22 shown in FIG. 3, respectively, and the gains G1 to G4 are adjusted by these voltage control amplifiers 307 to 310. It should be noted that the level of the signal in the preformat section can be adjusted by adding the gain after adjusting the gain in the addition part. The MO signal output shown in FIG. 1 corresponds to the verify reproduction signal 18 shown in FIG. 3, and the RF signal corresponds to the reproduction signal 17 shown in FIG. In the present embodiment, as described above, it is difficult to reduce the leakage of the old signal to the level required for the verify operation by the adjustment relying on the mechanical mounting accuracy. Detected, and depending on the amount, G1 to G4 in FIG.
By setting the gain of, the leakage of the old signal is almost completely removed. During the manufacturing of the drive device, mechanical and optical position adjustment of each sensor for laser, RF signal, servo signal, and laser power detection, adjustment of servo system gain, offset, and the like are performed. However, the gain adjustment of the present embodiment is performed after the end thereof.

When performing the above gain adjustment, first, the check mode switch 326 is turned on to put the drive device in the check mode. As a result, the drive device starts a series of balance adjustment operations in the RF system. Here, the E ² P connected to the drive controller 324
The ROM 325 is configured to be recordable only in this check mode, and stores data for each sensor necessary for gain setting. The disc used for this adjustment has standard values for the characteristics related to the reproduction signal amplitude such as reflectance, recording sensitivity, optical phase difference, etc. in advance even within the specifications of the disc to be used. It is a disc that serves as a standard for manufacturing drive devices. Hereinafter, this disc is referred to as a reference disc. In this case, when the drive device is started (before turning on the power and starting this automatic adjustment),
Data of an average value that is experimentally determined in advance is set as a default value from the controller 324 to each channel of the 4-channel D / A converter 319, and each value is set to a level necessary for performing a recording operation. The gains of the voltage controlled amplifiers 307 to 310 are set.

Next, the reference disk is attached to the drive device, the drive device is started up, and a weight state (a state where it remains on one track) is set at a certain predetermined track. In this state, the laser power is set to the reproduction power, and the absolute amplitude of the reproduction signal is adjusted as the first step. The output waveforms of the voltage controlled amplifiers 307 and 309 are shown in FIG. When adjusting the amplitude of the reproduction signal, first, the amplitude of the preformat section indicated by X in the figure is detected by the level detectors 311 and 315. Then, the amplitude value is set to A / D by the A / D converter 323.
After being D-converted, it is taken into the drive controller 324. The disc used here is a reference disc whose features are clearly defined.Therefore, by adjusting the gain so that the playback signal amplitude of this disc has a certain value, the absolute value between each drive is adjusted. It is possible to eliminate the difference in gain.

Therefore, the drive controller 324 compares the reproduction signal amplitude data of the preformat section reproduced by the gain set with the default setting value with the reference value stored in the controller 324 in advance,
The gains of the voltage control amplifiers 307 and 309 are reset according to the difference. Further, the controller 324 repeatedly adjusts the gain until the output values of the reproduction signal level detectors 311 and 315 described above fall within an allowable range with respect to a predetermined reference value. Here, the voltage control amplifier 30 at this time
The data of the set values to the 7, 309 are stored in the first and second addresses of the E ² PROM 325. This completes the adjustment of the absolute light amount. In the next step, the signal is recorded in advance in order to detect the amount of leakage of the old signal, the amount of leakage of the old signal when deleting it is detected, and the gain is adjusted to minimize it. Adjust. Less than,
This will be specifically described.

First, under the control of the drive controller 324, a repetitive signal which becomes a pit larger than the pit length which is the minimum recording pit normally recorded on the disc over a certain area of the disc over several tracks. To record. For example, when pit edge recording or 1-7 modulation is used, a 3T pattern repeating signal or the like is recorded. Next, the drive controller 324 sets the laser power to the recording power and then controls the current so that the magnetic head generates a constant magnetic field in the erasing direction (the direction opposite to the direction in which pits are recorded). FIG. 5 is a diagram showing current waveforms of the two-divided sensors 301 and 302 at this time. Two
The split sensor 301 is the first two-split sensor 1 shown in FIG.
5, the two-divided sensor 302 corresponds to the second two-divided sensor 16, respectively. Further, the sensors 301a and 301b of the two-divided sensor 301 correspond to the sensors 15a and 15b,
The sensors 302a and 302b of the two-divided sensor 302 correspond to the sensors 16a and 16b, respectively.

FIG. 5A shows this sensor 301a, FIG.
5B is a sensor 301b, and FIG. 5C is a sensor 302.
FIG. 5A is a diagram showing the current of the sensor 302b. Here, the signals of the sensors 301a and 302a are the light reception signals of the light reflected from the region sufficiently heated by the light spot, and the signals of the sensors 301b and 302b are the light reception signals of the light reflected from the low temperature region where heating is insufficient. Is. In addition, the sensors 301a and 302a and the sensor 30
1b and 302b are signals whose phases are inverted. When erasing a signal recorded at a constant frequency as described above, the sensors 301a and 302a are in a high temperature region, that is, the currently recorded signal (in this case, a constant level of direct current because of erasing) + leakage of the old signal. Is detected, the sensors 301b and 302b detect a low temperature region, that is, the leaked portion of the old signal + recording signal (DC level). Based on the sensor output thus detected, the gain of the voltage controlled amplifier is adjusted. The gains of the voltage controlled amplifiers 307 and 309 have already been set in the first step, and the voltage controlled amplifiers 308 and 310 are set here.

First, the voltage control amplifiers 308 and 310 are previously set.
Even if the leakage of the old signal is small by mechanically adjusting the gain of the voltage control amplifier 308, the voltage control amplifier 308 is overcompensated, that is, the signal for removing the leakage is increased and the component of the old signal is increased. , 310 is set to a large gain. Next, the gains of the voltage control amplifiers 308 and 310 are set to the D / A converter 31 for each sector.
The level detector 313, 317 detects the amplitude (AC component) of the old signal component of the output amplitude of the differential amplifier 312, 316 for each sector. Then, the value is A / D converted by the A / D converter 323 and taken into the controller 324. The relationship between the amplitude value of the old signal leakage component and the gain obtained here is as shown in FIG. Therefore, the amplitude data is compared with the sectors before and after, and the set value to the D / A converter 319 of the sector determined to be the minimum is set in the E ² PROM 32.
It is stored in the third and fourth addresses of No. 5.

With the above, the gain adjustment is completed, the check mode switch 326 is turned off, and the writing of data to the E ² PROM 325 is prohibited. After that, when using the drive device normally, E ² P
The data stored in the addresses 1 to 4 of the ROM 325 is sent to the D / A converter 319, and the voltage control amplifiers 3
The gains of 07 to 310 are set to the previously determined optimum gains.

As described above, the gain of the signal of the light receiving portion of each two-divided sensor can be automatically adjusted according to the degree of leakage which differs depending on the mounting accuracy of the sensor and the light beam. Therefore, it is possible to reliably remove the leakage component from the low temperature side in the light spot irradiation unit, that is, the old information component, from the reproduction signal for verification, and the quality of the reproduction signal for verification, which has been a problem of conventional direct verification, can be reduced. The reduction can be significantly improved.

In the above description, the gain adjustment between the sensors was performed using the reference disk when the drive device was manufactured. However, after the drive device is assembled, it is used every time the disk is attached to the drive during normal use. The same gain adjustment as described above may be performed by using a disc that is used. In this case, each data is stored in the RAM in the drive controller instead of the E ² PROM on the optical head.

[0025]

As described above, according to the present invention, a signal is recorded in a predetermined area, and when the location is erased, the difference in signal level between the divided elements of each two-divided sensor is reduced. By adjusting the gain of each gain adjusting unit to the minimum and storing the gain adjustment amount for each divided sensor in the storage unit, it is not necessary to adjust the position of the sensor with high precision, and verification by leaking of old signal is performed. It is possible to prevent the reliability of the reproduction signal for use from decreasing. Further, by incorporating the storage means in the head unit, there is an effect that the readjustment becomes unnecessary even when the head unit is replaced.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of an automatic gain adjustment circuit in a magneto-optical recording apparatus of the present invention.

FIG. 2 is a diagram showing a configuration example of an optical system of the magneto-optical recording apparatus of the present invention.

FIG. 3 is a diagram showing a light spot on an RF sensor and a signal detection circuit for reproducing a signal by the sensor output.

FIG. 4 is a diagram showing output signals of voltage controlled amplifiers 307 and 309.

FIG. 5 is a diagram showing currents of sensors 301a, b and 302a, b.

FIG. 6 is a diagram showing a relationship between an old signal leakage amplitude and a gain of a voltage controlled amplifier.

FIG. 7 is a diagram showing a schematic configuration of a conventional magneto-optical recording device for performing direct verification.

FIG. 8 is a diagram showing a light spot on a magneto-optical recording medium and its magnetization state.

FIG. 9 is a diagram showing a reproducing optical system improved in order to favorably perform direct verification in a conventional example.

[Explanation of symbols]

1 semiconductor laser 5 magneto-optical recording medium 9 servo sensor 12 RF sensor 30 optical head 15 first two-divided sensor 16 second two-divided sensor 19-22 gain adjusting mechanism 301,302 two-divided sensor 307-310 voltage control amplifier 311 , 313, 315, 317 Level detector 319 D / A converter 323 A / D converter 324 Drive controller 325 E ² PROM

Claims (5)

[Claims] 1. A light beam reflected from a magneto-optical recording medium is divided into two light beams within a plane including the track direction, and these two light beams are detected by a two-divided light receiving element, and In a magneto-optical recording apparatus that generates a reproduction signal for verification by taking a signal difference between elements, an amplification unit for varying the signal level of each of the two-divided light receiving elements and a gain of each amplification unit are set. Gain adjusting means for adjusting the gain that minimizes leakage of the old signal component into the two-divided light receiving element, and storage means for storing the gain obtained by the gain adjusting means are provided. A magneto-optical recording device characterized by the above. 2. The gain adjusting means records a signal in a predetermined area of a recording medium, and at the time of erasing the signal, the amplifying means is adapted to minimize a level difference between elements of the two-divided light receiving element. 2. The magneto-optical recording device according to claim 1, wherein the gain of the device is adjusted. 3. The magneto-optical recording apparatus according to claim 1, wherein the gain is determined by the gain adjusting means when the apparatus is manufactured. 4. The magneto-optical recording apparatus according to claim 1, wherein the gain is determined by the gain adjusting means when the recording medium is mounted on the apparatus. 5. The magneto-optical recording apparatus according to claim 1, wherein the storage means is provided on a unit including an optical head.