JPH0562237A - Optical head - Google Patents

Abstract

PURPOSE:To provide a small-sized optical head by simplifying a structural member or changing the arrangement of the member. CONSTITUTION:A slider 13 supported by a hinge 2 is loaded by an objective lens prism 15 forming integrally an objective lens and a reflection prism and a magnetic field generating coil 14. The slider 13 is detached by a specified distance to a recording face by rotating a magneto-optical disk 3. A laser beam L outgoing from a fixed optical system 1 is made incident on the objective lens prism, is converged, and is deflected and a light spot is formed on a recording layer 3a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical head used in an optical disk drive device or a magneto-optical disk drive device for focusing and deflecting a light beam.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing an example of a conventional optical head used in a magneto-optical disk drive device.

The optical head is composed of a fixed optical system 1 fixed to a magneto-optical disk drive device (not shown), a moving optical system 10 fixed to a hinge 2, and the like.

The fixed optical system 1 includes a semiconductor laser as a light source, a collimating optical section for collimating the laser beam, a signal detecting section for detecting the laser beam L reflected by the magneto-optical disk 3, and the like. The hinge 2 is moved in the radial direction (arrow A direction) of the magneto-optical disk 3 by a drive unit (not shown). The moving optical system 10 includes a reflection mirror 11, an objective lens 12, a slider 13, and a magnetic field generating coil 14.
Etc.

A laser beam L emitted from the fixed optical system 1 enters a reflecting mirror 11. The reflection mirror 11 reflects the laser beam L in the direction normal to the recording surface of the magneto-optical disc 3, and the laser beam L is focused by the objective lens 12 arranged between the reflection mirror 11 and the magneto-optical disc 3. A light spot is formed on the recording layer 3a of the magneto-optical disk 3. The slider 13 is configured to be separated from the recording layer 3a of the magneto-optical disc 3 by a certain distance.
Further, the magnetic field generating coil 14 is held so as to face the recording layer 3a. The magnetic field generating coil 14 is formed in a ring shape and is arranged so that the laser beam L focused by the objective lens 12 passes through the hollow portion. The magnetic field generating coil 14 is capable of applying a magnetic field to the point where the light spot of the recording layer 3a is formed by generating a magnetic field while the laser beam L is passing through the hollow portion. The magneto-optical disk 3 is rotated by a magneto-optical disk drive device (not shown) and is moved in the radial direction by the drive unit via the hinge 2, so that a light spot is formed at a desired point on the recording layer 3a. Form or apply a magnetic field.

As the magneto-optical disk 3 rotates, an air flow having a constant flow velocity is generated on the recording surface. At this time, the slider 13 has an aerodynamic lift due to its shape, and the hinge 2 has elasticity. As a result, the slider
Numeral 13 is a state in which the hinge 2 is flexed by a certain amount and the lift force and the hinge 2 are
The elastic force of is in agreement. This allows the slider 13
Keeps a state separated from the recording surface of the magneto-optical disk 3 by a specified distance. Moreover, the slider 13 is attached to the magneto-optical disk
It is also possible to cause the operation of separating from to be performed by an actuator provided in a drive unit (not shown).

[0007]

In the optical head having the above structure, the laser beam L emitted from the fixed optical system 1 is deflected by the reflecting mirror 11 in the moving optical system 10 and then enters the objective lens 12. ing. In such a configuration, the moving optical system 10 has heights because the respective members are arranged in the height direction and the moving optical system 10 needs to secure the focal length of the objective lens 12 in the height direction. Since h cannot be lowered, it is difficult to downsize the optical head.

An object of the present invention is to provide a compact optical head by simplifying or changing the arrangement of the constituent members.

[0009]

In order to achieve the above object, the present invention provides a light source unit for emitting a light beam and a light beam emitted by the light source unit for forming a light spot on an information recording medium. And an objective lens prism for converging and deflecting.

Further, a light source section for emitting a light beam, and a mirror having a concave reflecting surface for converging and deflecting the light beam emitted by the light source section for forming a light spot on the information recording medium are provided. It is characterized by having.

Further, a light source section for emitting a light beam, an objective lens for focusing the light beam emitted by the light source section to form a light spot, and a light beam focused by the objective lens for deflecting the light beam are formed on the information recording medium. And a deflecting unit for forming a light spot.

Further, a coil for applying a magnetic field is provided at the formation point of the light spot on the information recording medium.

Further, a slider which is disposed so as to face the information recording medium and floats above the information recording medium by a fluid dynamic pressure effect, and a flexibility which supports the slider and keeps the flying height of the slider constant. And a hinge.

[0014]

According to the above means, since the optical head is provided with the objective lens prism for converging and deflecting the light beam emitted from the light source portion in order to form the light spot on the information recording medium, One member allows for focusing and deflection.

Further, since the optical head is provided with a mirror having a concave reflecting surface for converging and deflecting the light beam emitted from the light source portion to form a light spot on the information recording medium, the optical head is provided with a single mirror. One member allows for focusing and deflection.

Further, an objective lens for converging the light beam emitted from the light source unit to form a light spot, and a deflecting unit for converging the light beam by the objective lens to deflect the light beam to form a light spot on the information recording medium are provided. By having the head,
The objective lens and the deflection unit can be arranged in the optical axis direction of the light beam emitted from the light source unit.

Further, since each of the above-mentioned optical heads is provided with a coil for applying a magnetic field to the formation spot of the optical spot on the information recording medium, the optical spot can be formed on the information recording medium or the magnetic field can be applied. Since the slider for flying above the recording medium and the flexible hinge for supporting the slider are provided, the optical head can be separated from the information recording medium by a predetermined distance.

[0018]

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

In each of the following drawings, members corresponding to those described in FIG. 4 are designated by the same reference numerals, and their description will be omitted or simplified.

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

An objective lens prism 15 is mounted on the slider 13 of the moving optical system 10. Objective lens prism
Reference numeral 15 denotes an objective lens and a reflecting prism which are integrally formed. The laser beam L incident on the incident surface 15a formed in a convex shape is focused and further reflected by the reflecting surface 15b to be recorded on the recording layer 3a. Form a light spot.

In the optical head having the above structure, the objective lens prism 15 can focus and deflect the laser beam L,
Further, since the laser beam is bent in the moving optical system 10, it is not necessary to secure the focal length on a straight line. Therefore, the height of the moving optical system 10 can be reduced, and a small optical head can be provided.

FIG. 2 is a block diagram of the second embodiment of the present invention.

A concave mirror 17 is mounted on the slider 13 of the moving optical system 10. The concave mirror 17 has a reflecting surface 17a.
The laser beam L incident on the reflecting surface 17a is focused and reflected simultaneously to form a light spot on the recording layer 3a. Further, the reflecting surface 17a is formed as an aspherical concave surface so that the light spot is not distorted.

In the optical head having the above structure, the concave mirror 17 can focus and deflect the laser beam L. Therefore, the height of the moving optical system 10 can be reduced, and a small optical head can be provided.

FIG. 3 is a block diagram of the third embodiment of the present invention.

An objective lens 12 and a reflection mirror 11 are mounted on a slider 13 of the moving optical system 10. Objective lens
Reference numeral 12 is arranged so that its optical axis coincides with the optical axis of the laser beam L emitted from the fixed optical system 1. The reflection mirror 11 reflects the laser beam L focused by the objective lens 12 and forms a light spot on the recording layer 3a.

In the optical head having the above structure, the objective lens 12 and the reflection mirror 11 are arranged in the horizontal direction, and the reflection mirror
Reference numeral 11 reflects the laser beam L focused by the objective lens 12 and bends it in the direction normal to the magneto-optical disk 3,
In the moving optical system 10, it is not necessary to secure the focal length on a straight line. Therefore, the height of the moving optical system 10 can be reduced, and a small optical head can be provided.

In each of the above embodiments, the magneto-optical disk 3 is used.
Fixed optical system 1 for tracking information tracks
By providing a deflecting member such as a galvanometer mirror in the inside, it can be performed with high accuracy.

[0030]

As described above, according to the present invention,
An objective lens prism for converging and deflecting the light beam emitted by the light source unit to form a light spot on the information recording medium, or a mirror having a concave reflecting surface, or the light emitted by the light source unit By providing an objective lens that converges the beam to form a light spot and a deflection unit that deflects the light beam collected by the objective lens to form a light spot on the information recording medium, downsizing can be achieved, and information can be reduced. By providing a coil for applying a magnetic field at the formation point of the optical spot of the recording medium, it can be used for magneto-optical recording, and by providing a slider and a flexible hinge, the optical head can be moved from the information recording medium. It is possible to provide an optical head capable of reducing the cost because a member such as an actuator that separates and adjusts the separation distance is unnecessary.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a third embodiment of the present invention.

FIG. 4 is a configuration diagram showing an example of a conventional optical head used in a magneto-optical disk drive device.

[Explanation of symbols] 1 ... Fixed optical system, 2 ... Hinge, 3 ... Magneto-optical disk, 3a ... Recording layer, 10 ... Moving optical system, 11 ... Reflective mirror, 12 ... Objective lens, 13 ... Slider, 14 ... Magnetic field Generator coil, 15 ... Objective lens prism, 17 ... Concave mirror.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuichi Honda 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Hideaki Kibune 1-3-6 Nakamagome, Ota-ku, Tokyo In stock company Ricoh (72) Inventor Haruhiko Kono 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh stock company (72) Intaker Takehide Ono 1-3-6 Nakamagome, Tokyo Ota-ku Ricoh company (72) Inventor Takashi Ogawa 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd.

Claims (5)

[Claims] 1. A light source unit for emitting a light beam, and an objective lens prism for focusing and deflecting the light beam emitted by the light source unit for forming a light spot on an information recording medium. And an optical head. 2. A light source section for emitting a light beam, and a mirror having a concave reflecting surface for converging and deflecting the light beam emitted by the light source section for forming a light spot on an information recording medium. An optical head characterized by having. 3. A light source section for emitting a light beam, an objective lens for focusing the light beam emitted by the light source section to form a light spot, and a light beam focused by the objective lens for deflecting the light beam on an information recording medium. An optical head, comprising: 4. The optical head according to claim 1, further comprising a coil for applying a magnetic field to a formation point of a light spot on the information recording medium. 5. The recording medium is arranged so as to face the information recording medium,
4. A slider, which floats above an information recording medium by a fluid dynamic pressure effect, and a flexible hinge, which supports the slider and keeps a floating amount of the slider constant. 4. The optical head according to any one of 4 above.