JPS5853034A - Driving device for optical system - Google Patents

Abstract

PURPOSE:To make the optical system light weighted, to quicken and make various operations stable, by providing a sub-arm for a main arm having the 1st optical system, and a sub-drive means and the 2nd optical system having a condenser lens opposing to the 1st optical system for the sub-arm. CONSTITUTION:The radial feeding is performed by a main driving means 1. The beam of the 1st optical system 3 is made incident to a condeser lens of the 2nd optical system 5 at the opposing position and forms the spot of a disc. Thus, the spot can be moved with the main drive means 1. The reflected beam returns to the 1st optical system 3 via the 2nd optical system 5 and obtains recording information and a control signal. A sub-drive means 7 receives the said control signal for focusing and tracking. This drive is performed with coils 9,10 and 11 for three axis drive fitted with a driving arm 8 of a sub-arm.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a former academic drive JI21fI used for reading recorded information from, for example, a video disc, an audio disc, or the like, or conversely for importing information.

In an optical video disk drive system, a laser beam emitted from a laser light source scans the disk tJ to record information t-a.
The disc can be used semi-permanently to read the data. C, it is said to be the most excellent system, and various proposals have been made for optical system drive devices used particularly in this field. However, an optical system drive device that can perform a single focusing operation or tracking operation at high speed and can stably perform radial feeding has not yet been realized.

The present invention has been made in view of the above points, and its purpose is to realize an optical system drive device f that is capable of high-speed focusing and tracking operations, stable radial feed, and has a simple structure. There is a particular thing.

The present invention will now be described in detail with reference to FIG.

FIG. 1 is a perspective view showing an embodiment of an optical system driving device according to the present invention, and this embodiment is embodied as a pickup device for reading 6-bit information from a disk.

In the figure, lrs is the main drive means, which consists of a pulse motor, a torque motor, etc. The main arm is rotated by the main driving means, and the first optical system 3 is attached to the main arm. This first optical system 3 is composed of a laser light source, a light receiving section, a lens, and the like. A first optical system j having a converging lens on the sub-arm supported by the main arm pri is mounted in a positional relationship opposite to the seventh optical system 3. The support of the sub-arm by the main arm is specifically carried out by a support B made of an elastic material. 7 is an auxiliary drive means, preferably X +
The first optical system in the 3-axis direction of 71 m! It is possible to drive For example, as shown in FIG. 2, this sub-driving means 7 includes a driving arm If provided at the other end of the sub-arm 3, and three coilers for adding a sword in three axial directions to this arm T.
io and ti are attached, and a permanent magnet (not shown) for placing the moving coils 2 to 1 in a certain magnetic field is attached to the other end of the main arm. If this is done, the permanent magnet will form part of the 7 ohm motor and will act as a counter-quaight for the optical system 3 of the SI.

Stable operation of the main armco and stable layer lI of the first optical system 3
You can aim for J.

In the embodiment described above, the radial feed 9 is performed by the main drive means l. The mountain bark laser beam from the light source in the seventh optical system 3 passes through the half mirror, lens, etc. of the optical system 3, and then enters the first optical system! The light is incident on the converging lens which forms a focusing lens to form a spot on the disk, and this spot is moved in the radial direction by the main driving means l. The reflected beam on the disk surface returns to the first optical system 3 again via the first optical system jt-, and reaches its light receiving section. This provides recording information as well as control signals for performing necessary focusing and tracking operations. The sub-drive means 7 receives the control signal and performs focusing and tracking.

In the above embodiment, the sub-arm l was supported by the elastic support t, but it may be supported by other means such as a knife edge, etc. Also, the sub-driving means 7 may be supported at any point on the arm. It may be something that acts on the sword, but it is directly the first Oaza system! It can also be something that exerts force on

Furthermore, although the above description is about the case where the main arm λ rotates, the above effect can be obtained even if the main arm λ does not rotate but moves in parallel, for example, on a rail.

As explained above, the present invention provides an optical system in which the first optical system including at least a light source is attached to the main arm, the main arm is moved to perform radial transport, and the optical system has at least four focusing lenses tM. attached to the secondary arm supported by the main arm.

This movement of the sub-arm performs focusing and tracking64), making it possible to reduce the depth of the sub-arm and the first optical system, thereby achieving faster focusing and tracking.

Since radial feeding is performed by a drive means separate from driving for focusing, etc., stable radial feeding can be performed without interference.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the optical system drive unit according to the present invention, which is embodied as an optical pickup, and Fig. 2 is a main part configuration showing an example of the sub-drive means in Fig. 1. It is a diagram. l...Main drive means λ...Main arm 3...
5gt optical system Hiroshi... secondary arm! ...First optical system t...Support 7,...Sub-driving means
l...driving arm, 10. //... Moving coil% Koto Kende Foster Electric Co., Ltd. agent Masuji Ijima Sukiji

Claims (1)

[Claims] a main drive means, a main arm driven by the main drive means, a first optical system attached to the main arm and having at least a light source inside, a sub arm supported by the main arm, and a main arm; K11r An optical system of gλ installed in a positional relationship opposite to the first optical system and having at least a focusing lens inside, and a sub-driving means for driving the first optical system or the rigid arm. An optical system section llb device comprising: