JPH0793781A - Optical pickup - Google Patents

Abstract

PURPOSE:To obtain an optical pickup constituted so that the positional accuracy of a magnet is enhanced and the fixing position thereof is accurately controlled when it is loaded. CONSTITUTION:This optical pickup for reproducing or recording information from/on an information recording medium makes a current flow to coils 8 and 9 and moving a lens 2 for guiding light by a magnetic field generated between the magnet 12 fitted to a yoke 10. Then, the yoke 10 is provided with a positioning means 30 for positioning the magnet 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup suitable for an optical disk device such as a magneto-optical disk (eg MD).

[0002]

2. Description of the Related Art An optical pickup is attached to an optical disk device such as a magneto-optical disk (for example, MD). In this optical pickup, in order to allow the objective lens for guiding light to follow the warp and surface deflection of the optical disc, the eccentricity of the optical disc, etc., an electric current is passed through the coil and generated between the magnet and the magnet attached to the yoke. By the magnetic field
The objective lens can be moved, for example, in the focus direction and the tracking direction.

This optical pickup passes laser light or the like through an objective lens to reproduce information recorded on an optical disk such as a magneto-optical disk or record information on a magneto-optical disk. .

[0004]

However, although this magnet is fixed to the yoke with, for example, an adhesive, it is difficult to accurately position this small magnet with respect to the yoke. Workability is poor.

For this reason, depending on the position where the magnet is fixed to the yoke, there is a possibility that the characteristics of the optical pickup cannot be stabilized (for example, balance characteristics and resonance characteristics).

Therefore, the present invention has been made to solve the above-mentioned problems, and an optical pickup capable of improving the positional accuracy when the magnet is mounted and managing the fixed position of the magnet with high accuracy. Is intended to provide.

[0007]

SUMMARY OF THE INVENTION In the present invention, the above object is achieved by applying a current to a coil and moving a lens for guiding light by a magnetic field generated between the coil and a magnet attached to a yoke. In an optical pickup for reproducing information on an information recording medium or recording information on an information recording medium, this is achieved by an optical pickup including a positioning means for positioning the magnet on the yoke.

In the present invention, the yoke is preferably marked as the positioning means. Also, preferably, the marking is a groove formed in the yoke.

[0009]

According to the above construction, the mounting position of the magnet is managed by the positioning means.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the examples described below are suitable specific examples of the present invention, and therefore, various technically preferable limitations are given, but the scope of the present invention particularly limits the present invention in the following description. Unless otherwise stated, the present invention is not limited to these modes.

FIG. 1 is a plan view showing a preferred embodiment of the optical pickup of the present invention. 2 is a side view of the optical pickup of FIG. 1, and FIG. 3 is a rear view of the optical pickup.

The optical pickup shown in FIGS. 1 to 3 is attached to, for example, an optical disc recording / reproducing apparatus for a magneto-optical disc. 1 to 3, the optical pickup has the following structure. The optical pickup has a bobbin 1. The bobbin 1 is provided with an objective lens 2. The objective lens 2 guides the laser light to the magneto-optical disk, or guides the return light reflected on the surface of the magneto-optical disk to the optical system. The bobbin 1 is provided with a focus coil 8 and a tracking coil 9.

On the other hand, as shown in FIGS. 4 to 6, the XY base 11 has a yoke 10. Magnets 12 and 12 are fixed to the yoke 10 via, for example, an adhesive.

Further, as shown in FIGS. 4 to 6, XY
Two yokes 22 are provided on the base 11. These yokes 22 are the focus coils 8 shown in FIG.
It is located between eight. The lead flexible substrate 3 shown in FIG. 1 is connected to the bobbin 1 and also to the arm 4.

By selectively supplying power to the above-mentioned focus coil 8 and tracking coil 9 via the lead flexible substrate 3, it is possible to follow warp and surface wobbling of the optical disc, eccentricity of the optical disc, and the like. The objective lens 2 can be moved along the tracking direction TRK and the focus direction FCS. That is, this optical pickup is a biaxial actuator.

Thus, in order to read information from the magneto-optical disk, the objective lens 2 can be moved in the focus direction FCS and the tracking direction TRK so that the objective lens 2 can follow the warp or surface wobbling of the optical disk or the eccentricity of the disk. Of.

By energizing the focus coil 8 and the tracking coil 9 in this way, a magnetic field is formed between the focus coil 8 and the tracking coil 9 and the magnets 8 to move the objective lens 2 into the focus direction FC.
It is possible to move in S and the tracking direction TRK.

As shown in FIGS. 7 to 9, the magnet 12 is fixed to the yoke 10 with an adhesive. In order to accurately position and bond the small magnet 12 to the yoke 10 at a predetermined position, a reference marking 30 serving as a reference for the positioning is formed on the yoke 10. This marking is preferably a V-shaped cut groove formed by pressing or the like, as shown in FIG. This V-shaped reference marking 3
By forming 0 and 30 on the two yokes 10, the magnet 12 can be correctly positioned and attached to the yoke 10.

Thus, when the magnet 8 is mounted on the yoke 10, it not only serves as a reference for accurately detecting the variation in the position of the magnet 8 on the yoke 10, but also the accuracy of the position when the magnet is mounted. It is possible to improve. By accurately positioning and fixing the magnet 8 with respect to the yoke 10 using the reference markings 30 and 30, it is possible to stabilize the characteristics required in advance as a so-called biaxial actuator (balance characteristics and resonance characteristics). It is possible to obtain.

The present invention is not limited to the above embodiment. For example, as the reference marking 30, in FIGS. 7 to 9, a V-shaped groove is formed. Not limited to this, a simple line may be written on the yoke as a positioning means for positioning the magnet with respect to the yoke. Further, as the positioning means, a protrusion may be formed on the yoke.

Further, the present invention can be applied to an optical disk device for recording / reproducing a magneto-optical disk (eg MD, mini disk) or an optical disk device for reproducing a magneto-optical disk (eg MD, mini disk). But,
Not limited to this, the optical pickup of the present invention can be applied to, for example, an optical disc device for recording and / or reproducing an optical disc (compact disc).

[0022]

As described above, according to the present invention, it is possible to improve the positional accuracy when the magnet is mounted, and it is possible to accurately control the fixed position of the magnet.

[Brief description of drawings]

FIG. 1 is a plan view showing a preferred embodiment of the optical pickup of the present invention.

FIG. 2 is a side view of the optical pickup shown in FIG.

FIG. 3 is a rear view of the optical pickup shown in FIG.

FIG. 4 is a plan view showing a base of the optical pickup of FIG. 1, a yoke integrated with the base, and a magnet attached to the yoke.

5 is a side view of the base of FIG.

6 is a rear view of the base of FIG.

FIG. 7 is a front view showing an example of reference markings for positioning a magnet with respect to a yoke.

FIG. 8 is a plan view of the yoke and the magnet of FIG.

9 is a perspective view of a yoke and a magnet shown in FIG.

[Explanation of symbols]

 1 Bobbin 2 Lens 8 Focus Coil 9 Tracking Coil 10 Yoke 11 XY Base 12 Magnet 30 Reference Marking (Magnet Positioning Means)

Claims (3)

[Claims] 1. A current is passed through a coil, and a lens for guiding light is moved by a magnetic field generated between the coil and a magnet attached to a yoke to reproduce information on the information recording medium or to record information on the information recording medium. In the optical pickup for recording data, the yoke is provided with a positioning means for positioning the magnet. 2. The optical pickup according to claim 1, wherein the yoke is marked as the positioning means. 3. The optical pickup according to claim 1, wherein the marking is a groove formed in the yoke.