JPH0430961A - Device and method for working lens in toric shape and nonspherical shape - Google Patents

Abstract

PURPOSE:To finish with polishing automatically toric and non-spherical shaped bodies of high shape accuracy, by providing the mean which uses two mounting rotating grinding wheel for rough and finishings and the mean which moves a grinding wheel spindle in its axial direction and which automatically operates from rough finishing up to finishing. CONSTITUTION:Two mounting rotating grinding wheel 5 are used and made in the same outer diameter by dressing them simultaneously. First, a grinding wheel spindle 6 is moved in its axial direction, after completion of rough finishing by a grinding wheel 5a for rough finishing and finishing is started with a finishing grinding wheel 5b. Then the relative relation of the grinding wheels 5 and a work 1 becomes constant without its fluctuation without rearrangement- changing the rough finishing grinding wheel 5a to finishing grinding wheel 5b, so the toric shape and nonspherical shape bodies having a high shape accuracy can be polished.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an apparatus for processing toric and aspherical objects suitable for forming toric lenses and aspherical lenses.

[Background of the invention]

Traditionally, toric lenses were processed using Japanese Patent Application Laid-Open No. 62-203.
As described in 744, a polishing plate is processed in advance into a shape that has a reciprocal relationship with the shape of the lens to be processed, and this polishing plate is pressed against a glass material, and the abrasive grains are spread between the gap between the polishing plate and the glass material. The above-mentioned conventional technique, which uses an optical polishing method in which the material is supplied and rubbed, can only process toric shapes as shown by the broken line in Figure 3. However, in applications such as laser beam printers, for example, it is possible to process It has been found that optical imaging performance can be improved by using a modified toric lens having a slightly deviated surface as shown by the solid line in the figure. FIG. 2 shows the configuration of the toric surface and aspheric surface processing apparatus.

A workpiece (workpiece) 1 is provided on a rotary table 2 that is rotated by a motor 12, and the rotary table 2 is provided on a linear table 3 that is movable back and forth. In order to drive this linear table 3, a piezo actuator 4 is used.
is used. On the other hand, in order to process the workpiece 1, a grindstone 5 is used, and this grindstone 5 is attached to an air spindle 6. What rotation speed is OOOrpm?
Rotates with high precision. Further, the air spindle 6 is configured to be able to swing in an arc shape by a worm 7 and a worm wheel 8 around an air spindle holding shaft 9 installed parallel to its rotation axis. The air spindle holding shaft 9 is fixed at both ends by support members 20a and 20b via angular contact type rolling bearings 21.

In the processing apparatus described above, two steps, rough processing and finishing processing, are performed to process toric-shaped and aspherical objects. Between these two processes, the positional fluctuation between the grinding wheel and the workpiece caused when the roughing grinding wheel and the finishing grinding wheel are exchanged causes variations in the depth of cut during finishing processing, which affects the shape accuracy of the surface shape of the workpiece. I will give you.

The present invention eliminates positional fluctuations between the grinding wheel and workpiece that occur during the transition from rough machining to finishing machining, and by keeping the relative relationship between the grinding wheel and workpiece constant, the toric surface and aspheric surface with high shape accuracy can be produced. It is an object of the present invention to provide a processing apparatus for toric and aspheric lenses suitable for processing lenses.

[Purpose of the invention]

In order to achieve the above object, the present invention provides a means for using two rotary grindstones for rough machining and finish machining in the above-mentioned apparatus, and for moving the abrasive spindle in the axial direction of the grindstone spindle, from rough machining to rough machining. It is equipped with a means for automatic movement up to finishing machining.

[Summary of the invention]

In the above-mentioned apparatus, the two-piece rotary grindstone is used and the two-piece rotary grindstone is simultaneously dressed to have the same outer diameter. First, after rough machining is completed using a rough machining whetstone, the above-mentioned whetstone spindle is moved in the axial direction of the whetstone spindle, and finishing machining is started. This allows the relative relationship between the grindstone and the workpiece to remain constant without changing without changing the roughing wheel to the finishing wheel, making it possible to process toric and aspherical objects with high shape accuracy. .

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 shows the configuration of an aspheric lens processing apparatus according to the present invention. The numbers in the figure correspond to those in FIG.

In order to process the workpiece 1, a two-piece rotary grindstone 5 is used, which is a rough processing grindstone 5a and a finishing grindstone 5b.This grindstone 5 is attached to an air spindle 6, and 10.
OOOrpm rotates with high precision at which rotation speed. These two mounted rotary grindstones 5 have the same outer diameter by dressing the two at the same time. In addition, the air spindle 6 is
Air spindle holding shaft 9 installed parallel to its rotation axis
It is configured to be able to swing in an arc shape with a worm 7 and a worm wheel 8 as the center. The air spindle holding shaft 9 is fixed at both ends by support members 20a and 20b via angular contact type rolling bearings 21. These are spindle base 30
This spindle base 30 is moved in the axial direction of the grindstone spindle by a spindle base feed motor 32 via a groove guide 31. At this time, the position is detected by the photomicrosensor 33.

Now, in machining toric and aspherical objects, after rough machining, the spindle base feed motor 32
The grindstone spindle can be moved in the axial direction of the grindstone spindle at , and finishing processing can be started. This allows the relative relationship between the grindstone and the workpiece to remain constant without changing the rough machining whetstone for a finishing whetstone, making it possible to machine toric and aspherical objects with high shape accuracy. .

Here, the present invention is applied to a two-piece rotary whetstone 5, which is a rough machining whetstone 5a and a finishing whetstone 5b, but the present invention can also be applied to a multiple-width rotary whetstone or a single rotary whetstone used at several locations. The present invention can be applied.

〔Effect of the invention〕

According to the present invention, automatic machining from rough machining to finishing machining of toric and aspherical objects with high shape accuracy is possible, and it is possible to put such lens machining into practical use.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an aspherical lens processing apparatus of the present invention, FIG. 2 is a perspective view showing an aspherical lens processing apparatus, and FIG.
The figure is a perspective view showing the shape of an aspherical lens. In the figure, 1 is a workpiece, and 2 is a rotary table. 3 is a linear table, 4 is a piezo actuator, 5a is a roughing grindstone, 5b is a finishing grindstone, 6 is an air spindle, 7 is a worm, 8 is a worm wheel, 9 is a spindle holding shaft, 11 is processing data, 12 is the motor, 13
The rotary encoder 14 is a pulse motor, 15 is a non-contact displacement meter, 16 is a lens, 20a and 20b are support members,
21 is an angular contact type rolling bearing, 30 is a spindle base, 31 is a V-groove helical guide, 32 is a spindle base feed motor, and 33 is a photomicrosensor.揉f"-'! II A # $ f 4゛J'l m
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Claims (1)

[Scope of Claims] 1. A grindstone spin drill equipped with a rotating device for a workpiece, a rotary grindstone for processing the workpiece, a means for moving an axis of the grindstone spindle in an arc, and a rotation device for the workpiece. means for changing the distance between a shaft and a central axis of the circular motion of the grindstone spindle; a detector for detecting the rotational angular position of the workpiece; and a means for detecting the angular position of the circular motion of the grindstone spindle; Corresponding to these two detected angular position signals, the control data stored in advance in the storage means is read out,
In a processing device for toric and aspherical lenses having a control device configured to change the distance between the axes based on the read control data, a two-wheel mounted rotary grindstone for rough processing and finishing processing is provided. What is claimed is: 1. A processing device for toric and aspheric lenses, characterized in that a means for moving the grindstone spindle in the axial direction of the grindstone spindle and automatically operating from rough machining to finishing machining is provided. 2. A rotation device that holds and rotates a workpiece, a grindstone spindle equipped with a rotary grindstone that processes the workpiece, a means for moving the axis of the grindstone spindle in an arc, and a rotation axis of the workpiece. and a means for changing the distance between the center axes of the circular arc motion of the grinding wheel spindle, a detector for detecting the rotational angular position of the workpiece, and a means for detecting the angular position of the circular arc motion of the grinding wheel spindle. Corresponding to these two detected angular position signals, the control data stored in the storage means is read out, and the control data configured to change the distance between the axes based on the read control data is read out. In a processing device for toric and aspherical lenses, two rotary grindstones for rough processing and finishing are mounted on the grindstone spindle, and then dressed simultaneously to give the same external shape, and the rough processing grindstone A method of machining toric and aspheric lenses, which comprises rough machining the workpiece and then moving the grindstone spindle in the axial direction to perform finishing machining.