JPH0773531A - Magneto-optical disk drive device - Google Patents

Abstract

PURPOSE:To reduce power consumption of a bias magnet and also to simplify the structure by increasing the generation efficiency of a bibs magnetic field obliquely traversing the optical axis against a disk recording surface. CONSTITUTION:A magnetic head 01 is provided with a magnetic head coil lead 01A and a magnetic head core 01B whereon the coil is wound, and the magnetic head coil lead 01A is embedded in the notched part 01C of a slider. By embedding the lead in such a manner, a magnetic field generating part 02F at the end surface of an upper yoke 02A of the bias magnet is positioned at the end surface of the magnetic head slider, i.e., near the optical axis, thereby the magnetic field intensity on a magnetic field generating gap is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an objective lens driving device for controlling movement of an objective lens of an optical head in a seek direction, a tracking direction and a focus direction with respect to a disc-shaped magneto-optical recording medium, and an objective lens driving device. A magnetic head for applying a modulation magnetic field for magnetic field modulation recording to a minute area where laser light forms a light spot, and a bias magnetic field applying device for applying a bias magnetic field for optical modulation recording to the minute area are also provided. The present invention relates to a magneto-optical disk drive device.

[0002]

2. Description of the Related Art Conventionally, in this type of magneto-optical disk drive device, a constant magnetic field is applied to a magneto-optical recording medium by a bias magnetic field generator, and laser light modulated by applied recording information is supplied. When the information is recorded by irradiating the magneto-optical recording medium from the optical head, and when a certain laser beam is irradiated from the optical head to the magneto-optical recording medium, it is modulated by the given recording information. It is known that it can be applied to both the case of recording the information by applying a magnetic field to the magneto-optical recording medium.

For example, as shown in FIGS. 9 and 10, this is a structure in which a bias magnetic field generator for applying a constant magnetic field and a magnetic head for applying a high-speed modulated magnetic field are selectively used. Has become. Here, reference numeral 102 indicates that recording is performed by applying a constant magnetic field to the magneto-optical recording medium for optical modulation recording, and irradiating the laser light modulated based on the recording information from the optical head. A bias magnetic field generator for performing the operation, which is denoted by reference numeral 101, is a levitation type magnetic head which irradiates a magneto-optical recording medium for magnetic modulation recording with a constant laser beam and gives a high-speed modulated magnetic field. .

Here, a light source of a fixed optical system (not shown)
The laser light emitted from is reflected by a folding mirror (not shown), is condensed by the objective lens 103, and is irradiated onto the recording surface of the magneto-optical recording medium to form a light spot. The objective lens 103 is supported by a lens holder 103A, and the lens holder 103A is provided with an objective lens driving device 105 via an elastic supporting mechanism 103B such as a leaf spring.
The objective lens 103 can be focused and tracked on the recording medium by the movement control.

In the recording area of the magneto-optical recording medium including the light spot and its periphery, the magnetic head 10 for magnetic field modulation is used.
A modulation magnetic field is generated from the first magnetic field generation unit, and information can be recorded. In this case, the magnetic head 101 is fixed to the second drive mechanism 104, and the objective lens drive device 105 and the drive mechanism 104 are independently controlled to move in the disk radial direction of the recording medium. here,
When the fixed bias magnetic field generator 102 is used during the optical modulation recording, as shown in FIG. 9, the magnetic head 101 and its driving mechanism 104 are retracted in the direction of arrow c, and the fixed bias magnetic field generator 102 is moved to the arrow b. Descend in the direction. Then, a bias magnetic field is applied to the recording surface of the magneto-optical recording medium, and the modulated laser light is applied to the recording medium by the optical head to record information.

In addition, the magnetic head 1 uses the magnetic field modulation recording method.
Fixed bias magnetic field generator 1 when 01 is used
As shown in FIG. 10A, reference numeral 02 is an appropriate driving means and is retracted in the direction of arrow a. Therefore, as shown in FIG. 10B, the magnetic head 101 can move in the entire recording area of the magneto-optical recording medium, and the fixed bias magnetic field generator 102 drives the magnetic head 101 and its drive. It does not interfere with the mechanism.

[0007]

As described above, in the conventional apparatus, two types of magnetic field generators are prepared in order to deal with the optical modulation recording magneto-optical disk and the magnetic field modulation recording magneto-optical disk. When the magnetic head 101 is operating, the fixed bias magnetic field generator 102 is
Since it is configured to be retracted above 01, it is disadvantageous in reducing the size, weight and thickness of the device. In particular, the means for detecting the relative position between the optical axis of the objective lens and the magnetic head, and the mechanism for aligning them are complicated, and the structural complexity is inevitable.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent a fixed bias magnetic field generator from retracting in a magneto-optical disk device compatible with the above two types of recording methods in order to make the device compact and thin. However, it enables alternate use with magnetic heads and simplifies the structure for the retract operation.
At the same time, the arrangement of cores forming the magnetic field generating gap of the fixed bias magnetic field generating device and the gap adjusting means are optimized to provide a magneto-optical disk drive device in which the generation efficiency of the bias magnetic field at the laser spot position is improved. is there.

[0009]

Therefore, in the present invention,
The objective lens driving device that controls the movement of the objective lens of the optical head in the seek direction, the tracking direction, and the focus direction with respect to the disc-shaped magneto-optical recording medium, and the small area where the laser light from the objective lens forms a light spot. On the other hand, in a magneto-optical disk drive device equipped with a magnetic head for applying a modulation magnetic field for magnetic field modulation recording, and a bias magnetic field applying device for applying a bias magnetic field for optical modulation recording to the minute region as well; The head and the bias magnetic field applying device are configured integrally with the objective lens driving device and are movable in the radial direction of the magneto-optical recording medium; the objective lens driving device forms the objective lens driving magnetic circuit. A state in which a part of the yoke is circulated near the objective lens and is substantially parallel to the disk surface of the recording medium. The magnetic head is provided with a magnetic field generating portion on a flying slider, and is supported so as to face the magneto-optical recording medium and float or slide in the cartridge opening of the recording medium; The bias magnetic field applying device is configured such that its magnetic circuit includes an electromagnet, a core member, and a part of a yoke that circulates in the vicinity of the objective lens described above, and has a substantially ring shape having a gap in part as a whole. So that the light spot is located in the gap between the end of the core member and the yoke so that both of them face each other on the front and back sides of the recording medium; It is divided in the middle, and one of the cores is located at the joint so that it can rotate with respect to the other core in a plane parallel to the recording surface of the magneto-optical recording medium. The core, which is rotatably supported, is fixed to the magnetic head in a state in which the tip end portion of the core is positionally adjusted in a substantially circumferential tangential direction or a substantially radial direction of the magneto-optical recording medium. It is characterized by being.

Further, the yoke that circulates in the vicinity of the objective lens has an opening through which the laser light from the objective lens passes through the center, and the opening defines a light spot on the recording surface of the magneto-optical recording medium. It is characterized in that the portions facing each other are closer to the end portion of the core member toward the optical axis side of the laser light than other portions.

[0011]

Embodiments of the present invention will be specifically described below with reference to FIGS. FIG. 1 shows a magneto-optical disk drive device of the present invention. This device uses a magnetic head 01 for a magnetic field modulation recording system and a bias magnet 02 for an optical modulation recording system as an optical head carriage. It is installed in 06. Here, a magneto-optical disk (recording medium) 03 is controlled to rotate by a spindle motor 04.
Optical head carriage 06 for irradiating 3 with laser light
Is supported by a guide 08, and a linear motor 07 and a linear motor coil 07A mounted on the carriage perform seek operation in the radial direction of the disk to access a required recording area.

Further, the optical head carriage 06 includes
Actuator 05 for auto-focusing and auto-tracking the laser beam on the disc
Is installed. Further, as shown in FIG. 2, the magnetic head 01 is operated by the solenoid 10 at the time of optical modulation recording,
By moving the evacuation guide 09 downward, (B)
As shown in (C) and (C), the recording surface of the magneto-optical disk 03 is retreated.

Here, at the time of magnetic field modulation recording, as shown in FIG. 2B, the magnetic head 01 is loaded on the magneto-optical disk 03, and at the same time, the magneto-optical disk 03 is rotated by the spindle motor 04, and depending on the recorded information. The modulated magnetic field is applied from the magnetic head 01 to the magneto-optical disk, and as a result, information is recorded in the circumferential direction of the recording surface of the magneto-optical disk.

At the time of optical modulation recording, as shown in FIG. 2C, the retracting guide 09 is moved downward by the solenoid 10 so that the magnetic head 01 moves upward from the recording surface of the magneto-optical disk 03. A bias magnetic field is applied to the magneto-optical disk by the bias magnet 02, and a laser beam modulated by recording information is applied to the disk 03 surface by the actuator 05 mounted on the optical head carriage 06. Then, the information is recorded.

In the above structure, as shown in FIG.
The bias magnet 02 includes an upper yoke 02A located above the magneto-optical disk, a lower yoke 02B located below the magneto-optical disk, and an upper yoke 02A.
It is composed of a magnet coil 02C wound around. Then, the upper yoke 02A and the lower yoke 02B are joined at the joint portion 02D, and the upper yoke 02A is rotated in a plane parallel to the disc surface by the pin 02E provided at the joint portion 02D. The magnetic field generation unit 02F is movably supported, and its position is adjusted with respect to the magnetic head 01 as shown in FIG. 3A, and is provided to the actuator 05 as shown in FIG. 3C. The light flux escape ring portion 05B in the upper yoke 05A and the upper yoke 0A.
The bias magnetic field generation gap formed by the 2A magnetic field generation unit 02F is adjusted to the shortest distance as shown in FIG.

As another embodiment, the bias magnet 02 shown in FIG. 4 supports the lower yoke 02B thereof so as to be movable in the radial direction of the disk, as shown in FIG. 4 (B). 4, the skew adjustment gap of the actuator objective lens 05C with respect to the disk, which is provided between the lower yoke 02B and the actuator upper yoke 05A, is adjusted. As shown in B), the movement is adjusted in the disk radial direction and the actuator is brought into close contact with the upper yoke 05A, and as a result, the magnetic field generating portion 02 of the upper yoke 02A is moved.
The magnetic field strength in the bias magnetic field generation gap formed between F and the upper yoke 05A of the actuator is increased.

Further, as another embodiment, the magnetic head 01 shown in FIG. 5 has a magnetic head coil lead 01A, and
A magnetic head core 01B around which a coil is wound is provided, and the magnetic head coil lead 01A is embedded in the slider cutout portion 01C. By thus embedding the leads, the upper yoke 02A of the bias magnet can position the magnetic field generating portion 02F on the end face thereof near the end face of the magnetic head slider, that is, near the optical axis. The magnetic field strength at can be increased.

The embodiment shown in FIG. 6 is a modification of the embodiment shown in FIG. 3, in which the upper yoke 05A of the actuator (the yoke that circulates in the vicinity of the objective lens) is the laser light from the objective lens. Has an opening of a truncated circular shape that passes through the center thereof, and the opening has a portion 5B facing each other with a light spot on the recording surface of the magneto-optical disk interposed therebetween, as compared with other portions. The magnetic field generating gap is formed by the upper yoke magnetic field generating portion 02F and the upper yoke 05A, which is close to the upper yoke magnetic field generating portion 02F (end portion of the core member) of the bias magnet 02 toward the optical axis side of light. Is configured to be the shortest distance.

As another embodiment, the bias magnet 02 shown in FIG. 7 has an upper yoke magnetic field generator 02F.
And the upper yoke 05A of the actuator, the bias magnetic field generation gap of the light flux escape ring portion (the above-mentioned opening), and the yoke thickness in the optical axis direction of the portion 05B which is the bias magnetic field generation gap forming portion is set to the non-bias Region 05 for forming a magnetic field generation gap (leakage magnetic field generation gap)
It is thicker than the yoke thickness in the vicinity of C, and the yoke thickness on the non-bias magnetic field generation gap side is made sufficiently thin so that the transmitted magnetic flux becomes supersaturated. It increases strength.

As another embodiment, the pias magnet 02 shown in FIG. 8 has an upper yoke magnetic field generator 02F.
Regarding the bias magnetic field generating gap of the light flux escape annular portion (the above-mentioned opening) formed by the actuator and the upper yoke 05A of the actuator, the edge shape of the upper yoke magnetic field generating portion is specially considered. That is, a leakage that generates a magnetic field (indicated by a dotted arrow) without crossing the optical axis with respect to an edge A that forms a bias magnetic field generation gap that generates a magnetic field (indicated by a solid arrow) in the upper yoke across the optical axis. The edge of the upper yoke magnetic field generating portion is formed so that the edge B forming the magnetic field generating gap is located closer to the disk in the optical axis direction. As a result, from the edge B to the upper yoke 05 of the actuator.
The leakage magnetic field to A can be reduced, and the magnetic field strength from the edge A crossing the optical axis to the yoke 05B is increased.

[0021]

The present invention is as described above in detail,
The power consumption of the bias magnet can be reduced by increasing the generation efficiency of the bias magnetic field that crosses the optical axis diagonally with respect to the disk recording surface, and the bias magnet can be fixedly configured, so the structure is simple. Therefore, it is possible to obtain the excellent effects that the size, the weight and the thickness can be reduced as a whole.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of the present invention.

FIG. 2 is a schematic plan view showing each of the embodiments (A), (B), and (C), and a schematic side view of two operation modes.

FIG. 3 shows (A), (B), (C) the main parts of the embodiment.
FIG. 6B is a plan view, an end view, and a perspective view, respectively.

4A and 4B are a plan view, an end view, and a plan view, respectively, showing the main parts of the bias magnet and the optical head actuator of the embodiment in FIGS.

5A and 5B are an enlarged plan view and an end view, respectively, of a main part of the embodiment.

FIG. 6 is a plan view and an end view showing another embodiment of the present invention.

FIG. 7 is a plan view and an end view showing still another embodiment of the present invention.

FIG. 8 is a plan view and an end view showing another embodiment of the present invention.

FIG. 9 is a perspective view showing a conventional example.

10 (A) and 10 (B) are perspective views showing a usage mode of a conventional example.

[Explanation of symbols]

 01 magnetic head 01A magnetic head coil 01B magnetic head core 01C slider notch 02 bias magnet 02A upper yoke 02B lower yoke 02C magnet coil 02D joint 02E pin 02F magnetic field generator 03 magneto-optical disk 04 spindle motor 05 actuator 06 optical head carriage 07 Linear motor 07A Linear motor coil 08 Guide 09 Evacuation guide 10 Solenoid

Claims (6)

[Claims] 1. A disk-shaped magneto-optical recording medium,
Applying a modulation magnetic field for magnetic field modulation recording to the objective lens driving device that controls the movement of the objective lens of the optical head in the seek direction, the tracking direction, and the focus direction, and the minute area where the laser light from the objective lens forms a light spot. And a bias magnetic field applying device for applying a bias magnetic field for optical modulation recording to the minute region, wherein the magnetic head and the bias magnetic field applying device are the objective lens. The objective lens driving device is configured to be integrated with a driving device and is movable in the radial direction of the magneto-optical recording medium, and the objective lens driving device orbits a part of a yoke forming the objective lens driving magnetic circuit in the vicinity of the objective lens. Along with, it is arranged in a state substantially parallel to the disk surface of the recording medium, the magnetic head, The magnetic field generation part of is provided in a floating slider, and is supported so as to face the magneto-optical recording medium and float or slide in the cartridge opening of the recording medium. , The electromagnet, the core member, and a part of the yoke that circulates in the vicinity of the objective lens described above, and is generally in the shape of a ring having a gap in part, and the end of the core member Both of them are positioned so as to face each other on the front and back sides of the recording medium so that the light spot is positioned in the gap between the yoke and the core member, and the core member is divided in the middle thereof, and one of them is divided. The core is supported at the joint so as to be rotatable with respect to the other core in a plane parallel to the recording surface of the magneto-optical recording medium, and is rotatably supported. The core is formed integrally with the objective lens driving device in a state where the tip end portion of the core is adjusted in position in a substantially circumferential tangential direction or a substantially radial direction of the magneto-optical recording medium. Magneto-optical disk drive device. 2. The core that forms the gap between the yoke and the yoke, so that the end portion of the core can be adjusted with respect to the yoke in a plane parallel to the recording surface of the magneto-optical recording medium, The magneto-optical disk drive device according to claim 1, which is supported. 3. The apparatus according to claim 1, wherein the flying slider is provided with a notch portion including a lead wire of the magnetic head coil at a position near the magnetic head core in which the magnetic head coil is arranged, 2. The magneto-optical disk drive device according to claim 1, wherein an end portion of the core member is arranged close to the cutout portion. 4. A disk-shaped magneto-optical recording medium,
Applying a modulation magnetic field for magnetic field modulation recording to the objective lens driving device that controls the movement of the objective lens of the optical head in the seek direction, the tracking direction, and the focus direction, and the minute area where the laser light from the objective lens forms a light spot. And a bias magnetic field applying device for applying a bias magnetic field for optical modulation recording to the minute region, wherein the magnetic head and the bias magnetic field applying device are the objective lens. The objective lens driving device is configured to be integrated with a driving device and is movable in the radial direction of the magneto-optical recording medium, and the objective lens driving device orbits a part of a yoke forming the objective lens driving magnetic circuit in the vicinity of the objective lens. Along with, it is arranged in a state substantially parallel to the disk surface of the recording medium, the magnetic head, The magnetic field generation part of is provided in a floating slider, and is supported so as to face the magneto-optical recording medium and float or slide in the cartridge opening of the recording medium. , The electromagnet, the core member, and a part of the yoke that circulates in the vicinity of the objective lens described above, and is generally in the shape of a ring having a gap in part, and the end of the core member The light spot is positioned so as to be located in the gap between the yoke and the yoke so as to face both sides of the recording medium. The laser light has an opening portion that passes through the center, and the opening portion is a portion facing each other across a light spot on the recording surface of the magneto-optical recording medium, as compared with other portions, A magneto-optical disk drive device which is close to the end of the core member toward the optical axis side of the laser light. 5. The yoke that circulates in the vicinity of the objective lens has an objective lens circling yoke portion that is opposite to the other with a light spot on the surface of the magneto-optical recording medium sandwiched from the core end portion that forms the ring-shaped core gap. 5. The magneto-optical disk device according to claim 4, wherein the yoke portion is thicker in the optical axis direction of the yoke portion. 6. The core end portion forming the ring-shaped gap has a shape in which a portion close to the optical axis is close to the disc-shaped magneto-optical recording medium in the optical axis direction with respect to a portion away from the optical axis. The magneto-optical disk device according to claim 4, which is characterized in that.