JPH08132340A - Grinding and polishing of lens - Google Patents

Abstract

PURPOSE: To increase working efficiency by conducting first rough grinding by means of a forced cutting method in which a spherical surface generator (CG) is employed, conducting next fine grinding by means of a CG-employed forced cutting method, and then conducting constant-pressure cutting type copypolishing in which a polishing machine is employed, thereby reducing working stages of constant-pressure cutting type copying work, which requires much labor and a high level of skill. CONSTITUTION: In a rough grinding stage by means of a spherical surface generator (CG), a diamond-cup type grindstone is employed and grinding work is conducted by a forced cutting method. In a subsequent fine grinding stage by means of CG, the diamond-cup type grindstone is employed and grinding work is conducted by a forced cutting method. In the last polishing stage, a sheet bowl that is prepared by sticking a polyurethane sheet on a bowl is employed, and polishing work is conducted by a constant-pressure cutting type copying method, employing a polishing machine and supplying slurry.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for grinding and polishing optical elements such as lenses.

[0002]

2. Description of the Related Art Conventionally, in grinding / polishing optical elements such as lenses, "Optical element processing technology" (published by the Optical Industry Technical Association S56.10.10), page 197, "5.1 Lens production process" , As shown in the example of "recessed flash high-speed polishing", the spherical grinding / polishing process is performed by the spherical grinding process performed by the forced cutting process by the spherical surface generator (CG) and the constant pressure cutting profile process by the fine grinding machine. It was performed in three steps, a precise grinding step and a polishing step performed by a constant-pressure incision copying process by a polishing machine (see FIG. 4).

[0003]

However, in the above-mentioned conventional technique, there are two steps of constant-pressure incision copying in three steps, and a grindstone having a highly accurate spherical surface is required for two steps.
There is a problem that a great number of man-hours are required for setup. In addition, a great deal of man-hours and a high degree of skill are required to control the process accuracy during processing.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a lens grinding / polishing method having a high processing efficiency by reducing the constant pressure cutting profile processing step which requires a great number of steps and a high degree of skill. To aim.

[0005]

To achieve the above object, the lens grinding / polishing method of the present invention comprises a rough grinding step performed by a forced cutting method using a spherical surface generator (hereinafter referred to as CG), and a CG
It is characterized in that it comprises a fine grinding process performed by the forced cutting method by the above and a polishing process performed by the constant pressure cutting copying method by a polishing machine.

In this case, as described in claim 2, the bond material of the grindstone used in the fine grinding step is preferably made of metal, metal resin or resin.

Further, as described in claim 3, the tool used in the polishing step is preferably a sheet dish or a fixed abrasive polishing wheel.

[0008]

The operation of the lens grinding / polishing method of the present invention having the above construction will be described in detail with reference to FIG.

FIG. 1 shows a lens grinding / polishing process. That is, the precision grinding process, which has been conventionally performed by the constant-pressure incision copying process by the fine grinding machine, is performed by the CG forcible cutting process by using a cup-shaped grindstone of a high mesh having a small abrasive grain size. As a result, a large number of man-hours and highly skilled work that occur in constant-pressure incision copying are reduced.

[0010]

Embodiments of the lens grinding / polishing method according to the present invention will be described below with reference to the accompanying drawings.

(Embodiment 1) FIG. 2 shows a lens grinding / polishing method according to Embodiment 1. In the figure (a), lens grinding
It is a flow of a polishing process, and FIG. 9B shows a tool used in the polishing process.

(Structure) In the rough grinding process using CG, a diamond cup type grinding wheel having a grain size of # 325 is used to perform a total cutting amount of 0.6 mm by a forced cutting method.

In the following fine grinding by CG, the abrasive grain size is # 12.
Using a diamond cup type grindstone of No. 00, a total cutting amount of 0.1 mm is processed by a forced cutting method.

In the final polishing step, the sheet tray shown in FIG. 2 (b) in which the polyurethane sheet 1 is attached to the tray 2 is used, and slurry (abrasive material is cerium oxide) is supplied by a polishing machine. , 4μ total machining allowance with constant pressure cutting
Process m.

The above processing steps are applied to both surfaces of the lens.

(Function) A biconcave lens made of a glass material FKO1 having a processing diameter of φ20 was processed in the processing steps having the above-described structure.

In the rough grinding process using CG, the roughness is 15 μm.
A machined surface of Rmax was obtained, and in the fine grinding step by CG, a machined surface of roughness 1 μm Rmax was obtained. In the final polishing step, a processed surface having a quality usable as a lens was obtained.

(Effect) According to this embodiment, lens grinding
The processing efficiency of polishing can be improved.

In this embodiment, in the fine grinding step using CG, the metal-bonded grindstone is used as the cup-shaped grindstone, but the present invention is not limited to this, and the same effect can be obtained by using a metal resin-bonded grindstone or a resin-bonded grindstone. Is obtained.

(Second Embodiment) FIG. 3 shows a tool used in the second embodiment. Note that FIG. 2A is used as the basic configuration of the processing step.

(Structure) The basic structure of the processing steps is the same as in the first embodiment.
Is almost the same as A different point is that a fixed abrasive grain grindstone 1 in which cerium oxide is hardened with a resin is used for a plate 2 as a tool used in the polishing process.

(Operation) With the above construction, since the tool used in the polishing step is a fixed-abrasive grindstone, the sheet of the sheet dish is not worn out and cannot be used, and the durability is remarkably increased by 3 to 4 times. Improved. Furthermore, even for small-lot production parts, from production to the next production,
By simply storing the tool in the water, it can be used for production as soon as it is taken out, which has significantly reduced the setup work required for machining.

(Effect) According to this embodiment, lens grinding
The processing efficiency of polishing can be improved.

[0024]

As described above, according to the lens grinding / polishing method of the present invention, the constant pressure cutting profile machining step requiring a great number of man-hours and high skill is reduced by one step. The processing efficiency of can be greatly improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a lens grinding / polishing method according to the present invention.

FIG. 2 is a block diagram (a) showing a lens grinding / polishing method according to Embodiment 1 of the present invention and a tool (b) used therein.

FIG. 3 is a view showing a tool used in Example 2 of the present invention.

FIG. 4 is a block diagram showing a conventional lens grinding / polishing method.

[Explanation of symbols]

 1 Polyurethane sheet or fixed abrasive whetstone 2 plates

Claims (3)

[Claims] 1. A rough grinding process performed by a forced cutting method using a spherical surface generator (hereinafter referred to as CG), a fine grinding process performed by a forced cutting method using CG, and a polishing process performed by a constant pressure cutting copying method by a polishing machine. Lens grinding / polishing method characterized by: 2. The lens grinding / polishing method according to claim 1, wherein the bond material of the grindstone used in the fine grinding step is one of metal, metal resin and resin. 3. The lens grinding / polishing method according to claim 1, wherein the tool used in the polishing step is a sheet dish or a fixed-abrasive grinding stone.