JPH0581723A - Magneto-optical disk driving device - Google Patents

Abstract

PURPOSE:To prevent the erasure of data on a disk even when an MO disk capable of recording and reading-out or a CCW disk capable of writing one time and reading any number of times is provided. CONSTITUTION:A magnet 11a for generating an external magnetic field in the magneto-optical disk driving device is fixed to the magnetic field of a recording direction. Thus, an erasing function is completely eliminated. Therefore, the danger of erasing the data of the MO disk and the CCW disk is eliminated.

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 device.

[0002]

2. Description of the Related Art There is known a magneto-optical disk in which a magnetic material is used as a recording medium to record and reproduce data with a laser beam. The magneto-optical disk has both the high-density and large-capacity characteristics of an optical disk and the erasability and re-recordability of the magnetic disk.

An optical modulation method is known as a method for recording / erasing data on such a magneto-optical disk.
In this optical modulation method, a weak magnetic field is applied to the magneto-optical disk in the vertical direction by an external magnetic field. With this magnetic field alone,
The direction of magnetization does not change due to the coercive force of the magneto-optical disk. Here, when the laser beam is applied to the portion to which the magnetic field is applied, the coercive force is reduced and the magnetization is reversed even in a weak magnetic field. Therefore, if the on / off of irradiation of the laser beam is controlled by the data to be recorded, a magnetic field corresponding thereto is formed on the magneto-optical disk and the data is recorded. Further, erasing can be easily performed by reversing the direction of the external magnetic field and irradiating the laser beam again to restore the magnetization direction of the magneto-optical disk to the original direction.

By the way, a magneto-optical disk is a normal M disk that can erase, record and read data many times.
In addition to O discs, there are discs (called CCW discs) that can be written only once and read many times. CCW discs are used, for example, when only reading is required without erasing the data recorded at the beginning.

For this reason, there has been proposed a multi-function drive device which can be driven regardless of whether a MO disc or a CCW disc is loaded. In this multifunction drive device, the mounted disc is an MO disc or C
It is determined whether it is a CW disk. If the disc is determined to be an MO disc, the erasing function, the recording function, and the reproducing function are applied, and the MO disc drive device is a normal MO disc drive device. Also,
When it is determined that the disc is a CCW disc, the recording function and the reproducing function are applied, and the disc drive device is a one-time write many-time read disc drive device.

[0006]

The multifunction drive device as described above has an erasing function. For this reason, the C
When a CW disc is loaded, the user may worry that the data recorded on the disc may be erased by mistake, or the data may be erased due to a discrimination error despite the CCW disc. There is a risk that

Therefore, an object of the present invention is to provide a magneto-optical disk drive device which does not erase the data on the disk regardless of whether an MO disk or a CCW disk is loaded.

[0008]

SUMMARY OF THE INVENTION The present invention provides a magneto-optical disk drive device capable of accepting both a erasable first magneto-optical disk and an erasable second magneto-optical disk. This is a magneto-optical disk drive device in which the erasing operation is not performed regardless of whether the magneto-optical disk or the second magneto-optical disk is mounted.

[0009]

By fixing the external magnetic field in the magneto-optical disk drive to the magnetic field in the recording direction, the data recorded on the magneto-optical disk is prevented from being erased.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an outline of a magneto-optical disk drive device to which the present invention is applied. In FIG. 1, reference numeral 1 is an interface controller for interfacing an input device such as an external keyboard with a magneto-optical disk drive device. The modulator and demodulator 2 connected to the interface controller 1 modulates recorded data and demodulates reproduced data.

The modulator and demodulator 2 are connected to a recording / reproducing circuit 3 including a laser driver, an RF amplifier and the like and an address decoder 4. Recording / playback circuit 3
A servo circuit 5 is provided in association with the. The output of the address decoder 4 is supplied to the servo circuit 5. The servo circuit 5 includes a tracking servo, a focus servo, a slide servo, and a spindle servo.

The servo circuit 5 allows the slide motor 6,
The optical head 7 and the spindle motor 9 are controlled. The slide motor 6 is for moving the optical head 7 in the radial direction of the magneto-optical disk 8. The optical head 7 irradiates a magneto-optical disk 8 with a laser beam for recording or reading, and detects a return beam from the magneto-optical disk 8. As the magneto-optical disk 8, either an MO disk or a CCW disk can be mounted. The recording signal from the recording / reproducing circuit 3 is supplied to the optical head 7, and the reproducing signal detected by the optical head 7 is supplied to the recording / reproducing circuit 3.

A drive control unit 10 connected to the recording / reproducing circuit 3 and the servo circuit 5 controls a magnet 11 which is disposed close to the surface of the magneto-optical disk 8 and which vertically generates an external magnetic field. To do. This magnet 11
It is fixed in the recording direction (for example, the side close to the surface of the magneto-optical disk 8 is the S pole and the opposite side is the N pole). The interface controller 1, modulator and demodulator 2, address decoder 4, drive controller 1
0s are connected to each other via a bus.

At the time of recording, the input data is modulated by the modulator and demodulator 2 and supplied to the laser driver of the recording / reproducing circuit 3. This drives the laser driver. Then, the laser beam output from the optical head 7 to the magneto-optical disk 8 is modulated with the recording data. Also, the servo circuit 5
The focus and tracking of the optical head 7 are controlled by the control signal from the.

At the time of reproduction, the signal recorded on the magneto-optical disk 8 is read by the laser beam from the optical head 7, and the reproduction signal is supplied to the RF amplifier of the recording / reproducing circuit 3. The output signal of the recording / reproducing circuit 3 is demodulated by the modulator and demodulator 2. Then, it is taken out from the external device connected to the interface controller 1.

FIG. 2 is a diagram showing a part of the above-described embodiment (around the optical head 7). As shown in FIG. 2A, when the magneto-optical disk 8 is rotated by the spindle motor 9, a magnet 11a for generating an external magnetic field is arranged vertically and close to the magneto-optical disk 8. Then, the optical head 7 emits a laser beam. The magnet 11a is fixed in the direction of the magnetic field used for recording data (for example, the side close to the surface of the magneto-optical disk 8 is the S pole, and the opposite skin is the N pole). Therefore, the direction of the magnetic field used for erasing is not reversed. Therefore, regardless of whether an MO disc or a CCW disc is loaded, the recorded contents of these discs will not be erased.

FIG. 2B uses an electromagnet 11b to generate an external magnetic field. The optical head 7, the magneto-optical disk 8 and the spindle motor 9 are the same as those shown in FIG. 2A.
Similar to that of. The drive current Iw for generating an external magnetic field is supplied from the drive circuit 12 to the electromagnet 11b. At the time of erasing, it is necessary to supply a current in the opposite direction to the current Iw at the time of recording to the electromagnet. In this embodiment, the drive circuit 12 is configured so that only the current Iw at the time of recording is generated. Therefore, regardless of whether an MO disc or a CCW disc is loaded, the recorded contents of these discs will not be erased.

[0018]

According to the present invention, the erasing function is completely removed by fixing the external magnetic field in the magneto-optical disk drive device. Therefore, MO disk and CCW
There is no risk of erasing data on the disc. Also,
Since it is not necessary to invert the external magnetic field, a circuit or the like for reversing is unnecessary, and the device can be downsized. Further, a magneto-optical disk recorded by an erasable device can also be mounted in the magneto-optical disk drive device according to the present invention.

[Brief description of drawings]

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

FIG. 2 is a diagram showing an example of the present invention.

[Explanation of symbols]

 8 Magneto-optical disk 11a Magnet 11b Electromagnet

Claims (1)

[Claims] 1. A magneto-optical disk drive device capable of accepting both a erasable first magneto-optical disk and an erasable second magneto-optical disk, comprising: the first magneto-optical disk and the second magneto-optical disk. A magnetic disk drive device in which an erasing operation is not performed even if any of the magneto-optical disks is mounted.