JPS6282519A - Optical pickup light beam angle adjustment mechanism - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a mechanism for adjusting the angle of light irradiation with respect to a disc in a pickup for an optical disc player.

FIG. 3 is a plan view of the disc and pickup in the optical disc player. FIG. 4 is a front view of the same.

In these figures, 3 is a pickup and 13 is a disk. The pickup 3 is shown in FIG.
By moving along the radial direction of the disk 13, information is recorded and reproduced from the inner circumference of the disk 13 to the outer circumference (or vice versa).

However, when the player is finished assembling,
When the disk 13 is set on a turntable (not shown), the disk is tilted by an angle θ with respect to the horizontal position (centered on the V-V' direction), as shown at 13a in FIG. , the entire structure is constructed.

The pickup 3 is positioned so that when the disk 13 is in the correct horizontal position (13 in Figure 4), it will correctly irradiate the laser beam to the disk, so even if the disk is tilted as shown at 13a. In this case, the laser beam cannot be irradiated correctly.

In this case, the irradiation angle of the laser beam toward the pickup 3 is set to θ
adjustment is made to correspond to the inclination of the disc.

The present invention relates to a mechanism (hereinafter sometimes referred to as a pickup angle adjustment mechanism) for adjusting the irradiation angle of a laser beam with respect to a disk of a pickup provided in a player based on such a need.

[Background of the invention]

As such conventional pickup angle adjustment mechanisms, those described in Japanese Utility Model Application Publications No. 58-109835 and 109836 are known, but in these conventional mechanisms, the angle of adjustment screws, fixing screws, etc. It is necessary to use special parts for adjustment, which has the disadvantage of increasing the number of required parts. Further, the adjustment work must be done from below the player, which has the disadvantage of poor workability.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a light irradiation angle adjustment mechanism for an optical pickup that has high precision and good workability without requiring the addition of special parts.

[Summary of the invention]

A shaft is inserted through one end of the pickup to guide the pickup while restricting its moving direction to one direction (radial direction of the disk), and a roller is tilted and pivotally supported at the other end of the pickup. When the pickup is guided by the shaft and moves, the roller supports the pickup diagonally and rotates on the floor in an inclined state. When the pickup is moved in a direction that intersects with the direction of movement, the pickup rotates around the shaft.
The light irradiation angle can be changed.

The present invention is based on this operating mechanism.

[Embodiments of the invention]

Next, an embodiment of the present invention will be described with reference to the drawings.

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

In the figure, 1 is a frame, 2 is a sliding surface, 3 is a pickup, 4 is an objective lens, 5 is an actuator, 6 is a roller, 7 is a shaft, and 8 is formed at the tip of the shaft 7 and is screwed with the pickup 3. 9 is a collar, 10 is a guide shaft, 13 is a disk, and 14 is a drive motor for the disk 13.

Note that parts not directly related to the present invention are omitted.

Now, an actuator 5 is incorporated in the pickup 3, and when the roller 6, which supports one end of the pickup 3 via a shaft 7 and a collar 9, rotates on the sliding surface 2, the other end of the pickup 3 is inserted into the actuator 5. The guide shaft 10 is moved along the guide shaft 10.

Of course, the direction of movement is along the radial direction of the disk 130.

The disk 13 shown by the broken line is used by being placed on a turntable (not shown) that is arranged concentrically with the shaft of a disk drive motor 14 fixed to the frame 1. disk 13
Needless to say, the laser beam for reading the optical axis recorded on the disk is irradiated onto the disk surface through the objective lens 4 attached to the actuator 5.

FIG. 2 is a cross-sectional view of FIG. 1 viewed from the A-A direction,
The optical axis l indicates that the laser beam is incident perpendicularly to the disk 13, and β' and l'' indicate that it is not incident perpendicularly.

Here, due to the action of the stopper 11 fixed to the shaft 7 which is screwed to the pickup 3 by the threaded part 8 and the compression spring 120, the roller 6 is always moved to the collar part 9 formed integrally with the shaft 7.
It is held in a pressed position. This position does not change even if the pickup 3 moves in the radial direction of the disk 13 (in the direction perpendicular to the plane of the paper in FIG. 2).

However, if the laser beam does not enter the disc surface perpendicularly to the optical axis l due to variations in the dimensions of the parts that make up the player or the inclination of the turntable surface, tighten the screw part 8. Rotate the shaft 7 using a screwdriver or the like in such a way as to loosen or loosen it. Then, the collar portion 9 advances or retreats as the threaded portion 8 advances or retreats, so that the roller 6 eventually moves on the sliding surface in a direction intersecting the sliding direction (in the left-right direction in the figure).

As a result, the pickup 3 rotates slightly around the shaft 10 in the direction of the arrow Y, so that the optical axis of the laser beam can be tilted in the l' or l'' direction.

By rotating the shaft 7 and adjusting it to advance or retreat relative to the pickup 3 in this way, it is possible to adjust the light irradiation angle of the pickup so that the laser beam is incident perpendicularly to the disk surface. Also, since this adjustment work can be done from the side of the pickup 3, the workability is superior to that of the prior art, which is done from below.

〔Effect of the invention〕

According to the present invention, a simple pickup angle adjustment mechanism can be realized by only partially changing the shape of the roller shaft, frame, etc. conventionally used in optical disc players, without requiring the addition of new parts. can do. Furthermore, if the inclination angle of the shaft supporting the roller is made gentle, the change in the light irradiation angle of the pickup with respect to the amount of rotation of the screw portion becomes small, so that the light irradiation angle can be easily finely adjusted. Furthermore, since adjustments can be made from the side of the pickup, work efficiency is also improved.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing essential parts of an embodiment of the present invention, Fig. 2 is a sectional view taken from the direction A-A in Fig. 1, and Fig. 3 is a plan view of a disc and a pickup in an optical disc player. , and FIG. 4 is a front view of the same. Description of symbols 1... Frame, 2... Sliding surface, 3... Pickup, 4... Objective lens, 5... Actuator, 6...
...Roller, 7...Shaft, 8...Threaded portion, 9...Brim portion, 10...Guide shaft, 11...Stopper, 12...Compression spring, 13...Disk, 14...
・Disk drive motor representative Patent attorney Akio Namiki Figure 1 M 2 Figure 1g35!3 114 Figure

Claims (1)

[Claims] 1) A guide shaft that is a mechanism for adjusting the angle of light irradiation with respect to a disk of an optical pickup, and that slidably engages one end of the pickup that moves along the radial direction of the disk and guides the movement; A screw member screwed onto the other end of the pickup in a direction inclined with respect to the light irradiation surface of the pickup is attached as a shaft, and when the pickup slides along the guide shaft,
a roller that supports the pickup obliquely on the other end side and rotates on the floor in an inclined state, and rotates the screw member at the threaded portion of the screw member with respect to the other end of the pickup. The roller, which is attached to the threaded member as an axis, is moved on the floor surface in an inclined state in a direction intersecting the moving direction of the pickup, thereby rotating the pickup in the vertical direction about the guide shaft. A light irradiation angle adjustment mechanism for an optical pickup, characterized in that the light irradiation angle with respect to a disk is adjusted by