JPS59224252A - Polishing device - Google Patents

Abstract

PURPOSE:To form various kinds of lenses having different radii of curvature with a high degree of accuracy, corresponding to the diameters of the cylindrical bodies, by providing such an arrangement that a workpiece held in a holder is pressed against the inner wall of a cylindrical body, and the holder is reciprocated while the cylindrical body is rotated. CONSTITUTION:A cylindrical body 100 having its inner wall lined with polyurethane 300 is set on a rotary roller 6 which is rotated in the direction 7 to rotate the cylindrical body 100 in the direction 8. A workpiece holder 9 is reciprocated in the directions to and from the cylindrical body 100 by an eccentric cam 11 through a reciprocating motion generating device 12 under repulsion of a spring 13. Then, a lens 200 as a workpiece is held in the holder 9, and is pressed against the polyurethane 300 lined to the cylindrical body 100 and as well against abrasive or the like applied to the inner surface of the cylindrical body 100 under rotary motion of the cylindrical body 100 and reciprocating motion of the holder 9, thereby a cylindrical lens 200 having a curved surface whose radius of curvature equals to the radius of the inner wall of the cylindirical body 100.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a mirror polishing apparatus for optical cylindrical lenses.

Conventional Structures and Problems With the spread of compact desk players, cylindrical lenses are being used in optical pickup mechanisms. For example, a cylindrical lens is used in the astigmatism method of focus servo of a pickup.

Figure 1 shows a typical manufacturing method for cylindrical lenses.
It was created using the method shown in Figure 2.

Fig. 1 shows a side view of the main parts of the cylindrical grinding device. 1 is a rotating grindstone, 2 is a rotating jig, 3 is a cylindrical lens, 4 is a fixed jig, 5 is a rotation direction, and R is a radius of curvature of the lens. .

When this device is used, the work of replacing the rotary grindstone 1 and the work of fixing the lens during the lens polishing process are cumbersome, and the grinding device is still expensive.

FIG. 2 shows a method of cutting out a cylindrical lens. The cylindrical lens 10 is cut from points A and A', and the main surface of the cut is polished.

This method has the disadvantage that as the curvature half 8R of the lens becomes thicker, it becomes difficult to cut A and A'.

OBJECTS OF THE INVENTION The present invention eliminates the above-mentioned conventional drawbacks and provides a polishing device that can produce cylindrical lenses with high precision.

Structure of the Invention The polishing device of the present invention includes a cylindrical body having openings at both ends;
A polyurethane vent provided on the inner wall surface of the cylindrical body,
A workpiece holder for holding a workpiece, means for pressing the workpiece held by the workpiece holding part against an inner wall of the cylindrical body, and means for rotating the cylindrical body around an axis. , means for reciprocating the workpiece holding part in the axial direction of the cylinder, using a polishing agent on the inner wall of the cylinder,
The main plane of the workpiece is polished into a curved mirror surface.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described below with reference to the perspective view shown in FIG. In the figure, a cylindrical body 1o○ whose inner wall is pasted with a polyurethane material is placed on a rotating roller 6, and as the rotating roller 6 rotates in the direction of 7, the cylindrical body 100 rotates in the direction of 8. . Workpiece holding part 9
Due to the rotation of the eccentric cam 11, reciprocating motion is generated in the cylindrical axis direction 14 of the cylindrical body 1o○ by the repulsion of the reciprocating motion generating section 12 and the spring 13. 15 and 16 are connecting rods for transmitting reciprocating motion, and 17 is a connecting hole thereof.

FIG. 4 shows a front view of the main part of the polishing process shown in FIG. 3.

In the figure, a lens 200, which is a workpiece, is held by a workpiece holding section 9 by adhesive. The lens 200 is pressed against the polyurethane material 300 of the cylindrical body 100 and the polishing agent etc. by the rotational movement of the cylindrical body 1000 and the reciprocating movement of the workpiece holding part 9, and the radius R of the inner wall of the cylindrical body 1o○ is
Cylindrical lens 20 with the same curved surface (R surface) as
0 is obtained. The radius R of both chambers of the lens can be set by the radius R of the cylindrical body, and when changing the curvature of the lens, it is only necessary to prepare a cylindrical body of the required diameter, which can be said to be economically advantageous.

FIG. 5 shows a perspective view of the cylindrical lens 200 produced in this example.

As described in detail of the invention, when processing a cylindrical lens using the polishing apparatus of the present invention, various types of lenses with a radius of curvature H can be created by simply selecting the desired diameter of the cylindrical body, reducing manufacturing costs. There is a dog that can be used to reduce emissions, and it is useful in industry.

[Brief explanation of the drawing]

Fig. 1 is a side view of main parts of a conventional cylindrical grinding device for processing cylindrical lenses, Fig. 2 is a perspective view of a conventional example in which a 7-lindrical lens is made from a cylindrical lens, and Fig. 3 is a perspective view of a cylindrical grinding device according to the present invention. FIG. 4 is a perspective view of the polishing apparatus of the embodiment, FIG. 4 is a front view of the essential parts of the polishing apparatus of FIG. 2, and FIG. 5 is a perspective view of a cylindrical lens produced according to the present invention. 100...Cylindrical body, 6...Rotating roller, 7,8°14...Rotation and reciprocating direction, 9
... Workpiece holding part, 11 ... Eccentric cam, 12
．． 13...Reciprocating motion generating part and spring material, 15.1
6... Reciprocating movement connecting rod, 17... Connection hole, 200
...Cylindrical lens, 300...--Polyurethane material. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (1)

[Claims] A cylindrical body with openings at both ends, a polyurethane sheet provided on the inner wall surface of the cylindrical body, a workpiece holding part for holding a workpiece, and a workpiece held by the workpiece holding part. The cylindrical body includes means for pressing a workpiece against an inner wall of the cylindrical body, means for rotating the cylindrical body around an axis, and means for reciprocating the workpiece holding part in the axial direction of the cylinder. 1. A polishing device characterized in that a polishing agent is used on the inner wall of the polishing device to process the main plane of the workpiece held in the workpiece holding portion into a curved mirror surface.