JPH0684191A - Optical-head carriage driving gear - Google Patents

Abstract

PURPOSE:To simplify each driving mechanism and to perform a highspeed access operation by a comparatively simple constitution. CONSTITUTION:An optical head 2 is supported by a base 13 via a support member 6, and the base 13 is arranged on a carriage rail 10 so as to be freely movable by a carriage roller 11. A magnet 9 and a yoke 15 are arranged at the outside of the carriage rail 10. In addition, a coil 7 for focusing use and a coil 8 for tracking use are arranged in a part faced with the magnet 9 of the base 13, and the magnet 9 is used as a common magnetic circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive coil and a carriage mechanism of an optical optical head used in an optical disk recording / reproducing apparatus for recording information on a rotating flat disk or reproducing already recorded information. It is a thing.

[0002]

2. Description of the Related Art As an apparatus for optically recording information on a concentric circle or a spiral track formed on a rotating disk, or for optically reading and reproducing already recorded information, , Compact discs and optical video discs that record information in the form of irregularities and irradiate it with a light beam to reproduce by utilizing the interference of light, or magneto-optical discs that record and reproduce using the magneto-optical effect. The device has already been put to practical use.

In addition, the optical head optical system as shown in FIG. 3 is constructed by a waveguide to reduce the weight and size. For example, this carriage driving mechanism enables focusing and tracking of the optical head 23. Like parallel leaf spring 21
It is supported by a biaxial actuator composed of a combination of a hinge 22 and a hinge 22 so that a beam spot 26 from the optical head 23 is irradiated to a predetermined position on the disk. The shaft actuator is driven to a predetermined position by a carriage driving means such as a linear motor 30.3.

Therefore, although the optical head can be made smaller and lighter by making the optical head a waveguide type from ordinary optical elements such as prisms and lenses, a biaxial actuator is used for driving and controlling the beam spot. By mounting it on the disk, a biaxial magnetic circuit, that is, a coil and a magnet, a yoke and the like and a coil for driving the carriage are mounted, and it has been impossible to make a revolutionary reduction in size and weight.

[0005]

As described above, in the conventional optical head, the mechanism for driving the beam spot in two axes and the mechanism for driving the carriage are attempted to reduce the weight of the movable portion in order to achieve high-speed access. Therefore, it is necessary not only to reduce the size and weight of the optical head only, but also to reduce the size and weight of each drive mechanism.

[0006]

In order to solve the above problems, according to the present invention, a light source, a deflecting element, a condensing element, a detector and the like are provided and a waveguide type optical head is provided between a carriage base and a supporting member. Provided is an optical head carriage driving method which is characterized in that it supports and can drive focusing and tracking by at least two kinds of coils, and the driving force of these coils is constituted by a common magnetic circuit.

[0007]

With the above construction, the weight of the movable portion can be reduced, the number of parts can be reduced at the same time, and low cost and high speed access can be achieved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 1 is a perspective view of an optical head carriage drive system of the present invention.

FIG. 2 is a cross-sectional view of the optical head carriage drive system of the present invention.

The optical head 2 is supported by at least two supporting members 6 made of, for example, leaf spring members, and is movable in the distance direction to the disk.

Further, the focusing coil 8 and the tracking coil 8 are provided so that the coil wire rods of the effective portions are orthogonal to each other. For example, as shown in the figure, in the focus coil 7, a coil wound in a plane circumferential shape is bent at least at one place, and a winding portion in the track direction is used as an effective portion.
The track coil 8 has a configuration of a coil wound in a cylindrical shape and uses the magnet 19 side as an effective portion.

The optical head 2 comprises a light source 3, a deflection element 5, a diffraction grating 4, a detector 3 ', etc. on a waveguide.

That is, the light emitted from the light source 3 passes through the waveguide, passes through the deflection element 5, and enters the diffraction element 5. The light diffracted by the diffraction grating 5 becomes the focused light 12 and becomes the waveguide surface. It is emitted perpendicularly to and is condensed on the disk 1.

The light reflected by the disk enters the waveguide in the reverse path, separates the signal light and the like by the deflecting element 5, and enters the detector 3 '. The light detected by the detector 3'is various signals. Become light.

The optical head 2 is supported by a supporting member 6,
The base 13 is provided with carriage rollers 11 at six positions above and below the carriage rail 10, for example, and is supported in the horizontal direction (track direction) with high accuracy and with low frictional resistance.

A magnet 9 and a yoke 15 are arranged on both sides outside the carriage rail 10 to form a common magnetic circuit for driving the optical head in the focus direction and the track direction.

Therefore, since the members from the movable base 13 to the light beam 12 do not need to have a magnetic circuit such as a magnet or a yoke, the weight reduction is realized.

[0019]

As described above, according to the present invention, it is possible to reduce the weight of the movable portion of the optical head using the waveguide. Further, since the magnetic circuit is configured on the fixed side other than the movable side, Even if the size is increased, the weight of the moving part is not affected. That is, by making the magnetic circuit strong, it is possible to obtain high sensitivity and high-speed access.

[Brief description of drawings]

FIG. 1 is a perspective view of an optical head carriage drive mechanism according to an embodiment of the present invention.

2 is a cross-sectional view of FIG.

FIG. 3 is a configuration diagram of a conventional carriage drive using a waveguide type optical head.

[Explanation of symbols]

 1 Disk 2 Optical Head 3 Light Source 3'Detector 4 Diffraction Element 5 Deflection Element 6 Support Member 7 Focusing Coil 8 Track Coil 9 Magnet 10 Carriage Rail 11 Carriage Roller 12 Light Beam 13 Base 20 Base 21 Parallel Leaf Spring 22 Hinge 23 Optical Head 24 Focusing Coil 25 Track Coil 26 Light Beam 27 Magnet 28 Carriage Roller 29 Carriage Rail 30 Coil 31 Linear Motor Yoke

Claims (2)

[Claims] 1. A magnetic circuit is provided in an optical head having a light source and an element having a deflection function on a waveguide, a mirror for reflecting light from the light source in a vertical direction, and a diffraction grating for condensing the light on a disk. , An optical head carriage driving device capable of focusing for controlling a distance from a disk. 2. The optical head carriage driving device according to claim 1, wherein the magnetic circuit for driving in the tracking direction is common to the driving in the focusing direction.