JPH11245152A - Polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform highly accurate finish polishing for the surface shape of an optical curved surface and to increase the efficiency of polishing work for the optical curved surface. SOLUTION: A polishing device polishes the optical curved surface 1a of a work 1 attached to a work holder 10. In this case, the device is provided with a polishing head 20 having a polisher 20 provided in its tip for machining the optical curved surface 1a of the work 1 while rotating it, a slider 18a for arranging the polishing head 20 and pressing the polisher 20 in the normal direction of the optical curved surface 1a, a motor 28 for rotating the polisher 21, a Z axis mechanism section 12 for moving the polisher 21 provided in the polishing head 20 arranged in the slider 18a in contact with or away from the optical curved surface 1a of the work 1, and a non-contact displacement gauge attached to the polishing head 20 and moved together with the polishing head 20. While the polisher 21 is in contact with the optical curved surface 1a, a distance is measured between the optical curved surface 1a and the non- contact displacement gauge, and the optical curved surface 1a is polished to have a desired shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus for polishing an optical curved surface of a workpiece by a polishing head, and more particularly, to rotating a polisher provided on the polishing head while moving the polishing head along the workpiece. And a polishing apparatus for polishing an optical curved surface.

[0002]

2. Description of the Related Art Generally, when polishing an optical curved surface of a surface to be processed, a polishing apparatus and a polishing method differ greatly depending on whether the optical curved surface has a spherical shape or another aspherical shape. Recently, as an apparatus for polishing an aspherical optical curved surface, a small tool polishing method using a small-diameter polishing tool is often used.

Conventionally, a polishing apparatus for polishing a rotationally symmetric aspheric optical curved surface is disclosed in Japanese Patent Publication No. 50152/1992. As a polishing apparatus for polishing an aspherical (free-form surface) optical curved surface other than the above-mentioned aspherical surface, there is one described in JP-A-6-126607.

First, a polishing apparatus disclosed in Japanese Patent Publication No. 4-50152 will be described with reference to FIGS. 8 is a perspective view, and FIG. 9 is a sectional view of a main part.

[0005] In this polishing apparatus, as shown in FIG. 8, a workpiece 50 as a workpiece is fixed to a work chuck 52 on a rotary table 51.
It is rotatable around one rotation axis. The rotary table 51 is mounted on an X-axis mechanism 53 that can be moved and positioned in the horizontal direction (X-axis direction).
0 can be moved in the horizontal direction by the X-axis mechanism 53.

A work 5 fixed to a work chuck 52
A tool 54 for polishing 0 is attached to the tip of a spindle 55 located above the work 50 and is rotatable. The spindle 55 is supported by a slider 58 mounted on an R-axis mechanism 57 which is one end surface of the θ mechanism 56. The θ-axis mechanism 56 is attached to the Z-axis mechanism 59, which is movable in the vertical direction (Z-axis direction) perpendicular to the X-axis direction, in a freely rotatable manner. It is possible to incline a predetermined angle (θ in the figure) so that the axis of the spindle 54 coincides with the normal line direction at the X and Z points of the surface (optical curved surface) of 50. A compression spring 60 for applying a spring force in the axial direction of the tool 54 is interposed between the spindle 55 and the slider 58, so that the pressure at which the tool 54 contacts the workpiece 50 can be adjusted. .

With such a configuration, the tool 54 and the work 50
Is relatively positioned in three axes of X, Z, and θ, and the tool 54 is brought into contact with the workpiece 50 at a constant pressure and polished, thereby enabling highly accurate aspherical mirror processing.

On the other hand, a polishing apparatus disclosed in Japanese Patent Application Laid-Open No. 6-126607 will be described with reference to FIG. FIG. 10 is a sectional view of the polishing apparatus.

In this polishing apparatus, a disk-shaped tool 62 for processing a processing surface (optical curved surface) 61 a of a workpiece 61 is rotatably supported by a polishing head 64 via a tool rotation shaft 63. The tool rotating shaft 63 is rotationally driven by a driving device 65, and is fixed to the tool rotating shaft 63.
Is rotatable about a tool rotation shaft 63.
Further, an NC table 66 that swings the polishing head 64 so that the tool rotation shaft 63 is parallel to the tangent C at the processing point is provided.

In such a configuration, the polishing head 64 is swung to make the tool rotation shaft 63 parallel to the tangent at the processing point, so that the processing surface 61a of the workpiece 61 is provided on the outer peripheral surface of the disk-shaped tool 62. Is pressed against the disk-shaped tool 62 and the processing surface 6.
The relative speed at the contact portion with 1a becomes uniform, and polishing can be performed with high accuracy.

[0011]

In general, the optical curved surface after polishing is required to have high shape accuracy, and in order to satisfy such a requirement, it is necessary to measure the shape of the optical curved surface during processing and obtain a desired shape. The shape is finished.

However, in the above-mentioned conventional polishing apparatus,
It is necessary to measure the shape of the optical curved surface with a shape measuring machine arranged at a position different from the polishing device, but in order to polish to the desired shape, remove the workpiece from the polishing device several times and It is necessary to repeatedly polish the optical curved surface while positively correcting the shape error from the desired curved surface shape by measuring the shape of the optical curved surface, and to make the optical curved surface shape accuracy the desired accuracy. Therefore, there is a problem that the processing time is lengthened because polishing and measurement of the processed shape are repeatedly performed while attaching and detaching between the polishing apparatus and the shape measuring machine.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and is capable of finishing and polishing a surface shape of an optical curved surface with higher accuracy and improving the efficiency of polishing of the optical curved surface. It is intended to provide a device.

[0014]

According to a first aspect of the present invention, there is provided a polishing apparatus for polishing an optically curved surface of a workpiece attached to a work holder. A polishing head having a polisher at its tip for processing while rotating an optical curved surface of a workpiece, pressing means for disposing the polishing head and pressing the polisher in a normal direction of the optical curved surface, and rotating the polisher Rotating means for moving, a moving means for moving a polisher provided on a polishing head provided on the pressing means so as to abut or separate from an optical curved surface of a workpiece, and the polishing head or the polishing head are provided. A non-contact displacement meter attached to the pressing means and moved together with the polishing head, and the distance between the optical curved surface and the non-contact displacement meter in a state where the polisher is in contact with the optical curved surface. Measured to measure the shape of the optical curved surface.

According to a second aspect of the present invention, in the polishing apparatus according to the first aspect, the non-contact displacement meters are respectively disposed before and after in the scanning direction of the polishing head.

Further, in the polishing apparatus of the present invention according to a third aspect, in the configuration of the first aspect, a hollow hole is provided in a rotation center axis of the polishing head, and a laser length measuring device is disposed above the hollow hole. .

That is, in the polishing apparatus according to the first aspect, the polisher provided in the polishing head is rotated by the rotating means for rotating the polisher, and the polisher is brought into contact with the optical curved surface of the workpiece by the moving means, and the pressing means is provided. Applies a constant processing pressure to the polisher. Then, while scanning a predetermined optical curved surface shape in this state and polishing with a polisher,
The distance to the optical curved surface is detected by a non-contact displacement meter attached to the polishing head or a pressing means provided with the polishing head. Then, polishing is performed while optimizing the polishing conditions based on the data, and the polishing is completed by setting the distance between the non-contact displacement meter and the optical curved surface to a predetermined value.

Further, in the polishing apparatus according to the present invention, the distance between both the unpolished surface portion and the polished surface portion on the optical curved surface is determined by the non-contact displacement meters arranged before and after in the scanning direction of the polishing head. Detecting and polishing while grasping the polishing status in real time.

Further, in the polishing apparatus according to the third aspect, a hollow hole is provided in the rotating shaft of the polishing head, and a laser beam is radiated from a laser length measuring device to the optical curved surface through the hollow hole above the hollow hole. The distance from the optical curved surface is measured, and the optical curved surface is polished into a desired shape as in the first aspect.

[0020]

[First Embodiment] A first embodiment of the present invention will be described with reference to FIGS. 1 to 3 show a polishing apparatus to which the present embodiment is applied. FIG. 1 is a front view, FIG. 2 is a left side view of FIG. 1, and FIG. 3 is a sectional view of a main part of a polishing head.

The polishing apparatus includes an X-axis mechanism section 2 and a Y-axis mechanism section which allow a workpiece 1 having an optical curved surface 1a to be polished as a workpiece to be moved in a horizontal direction (X-axis direction and Y-axis direction). 3 are provided.

The X-axis mechanism 2 includes a base 2 of the X-axis mechanism 2.
A moving table 2a is provided on the guide rail 2d to move linearly in the X-axis direction on the guide rail 2d in the horizontal plane (hereinafter, referred to as a horizontal plane). Moving table 2a
Is a stepping motor 2 attached to the side wall of the base 2b.
With c, it can be moved to a predetermined position, stopped and positioned.

The Y-axis mechanism 3 has a second base 3b mounted on a moving table 2a of the X-axis mechanism 2, and a guide rail (not shown) in the second base 3b is located on a horizontal plane. , A Y-axis moving table 3a capable of linearly moving in the Y-axis direction is provided. The Y-axis moving table 3a is moved in a Y-axis direction orthogonal to the moving direction of the moving table 2a by a stepping motor 3c mounted on a side wall of the second base 3b, and is stopped at a predetermined position and can be positioned.

The Y-axis mechanism 3 is provided with a θ-axis mechanism 5 that enables the rotation center axis 4 of the work 1 to be tilted in a plane perpendicular to the horizontal direction. The θ-axis mechanism 5 includes
As shown in FIG. 2, an L-shaped pedestal 5a fixed on the Y-axis moving table 3a is provided. The pedestal 5a can be moved to any position in the horizontal plane by the moving table 2a and the Y-axis moving table 3a. Can be moved and stopped. The motor 6 is mounted on the rear surface of the rising side surface of the pedestal 5a. A work spindle fixing plate 7 disposed on the front surface of the rising side surface of the pedestal 5a is attached to the drive shaft 6a of the motor 6. Drive shaft 6 of motor 6
“a” is rotatable about a horizontal axis 8 extending in the Y-axis direction and perpendicularly intersecting the rotation center axis 4 of the work 1.
The intersection between the rotation center axis 4 and the horizontal axis 8 is set to be the spherical center O (the center of the radius of curvature of the optical curved surface 1a) of the optical curved surface 1a to be polished of the work 1, and the work spindle fixing plate 7 Can be swung by a motor 6 around a horizontal axis 8, that is, a ball center O within a predetermined swing angle range.

A work spindle 9 is attached to the work spindle fixing plate 7. Work spindle 9
, A work holder 10 that rotates about the rotation center axis 4 of the work 1 is rotatably held. A motor 11 is connected below the work spindle 9.
1, the work holder 10 is rotated.

The work 1 can be removably attached to the work holder 10 with the optical curved surface 1a facing upward. The work 1 is attached and detached by moving a holding chuck (not shown) that can be freely opened and closed from the outer circumferential direction of the work 1.

On the base 2b of the X-axis mechanism 2, a stand 13 constituting a part of the Z-axis mechanism 12 is provided upright behind the moving table 2a of the X-axis mechanism 2. The Z-axis mechanism 12 moves the polishing head 20 having a polisher 21 for polishing the optical curved surface 1a of the work 1 attached to the work holder 10 in the vertical direction (Z-axis direction). A pair of guides 14 provided on both upper side surfaces of the stand 13,
And a slide plate 15 that is guided in the vertical direction and moves vertically. That is, the Z-axis mechanism 12 is
Of the optical curved surface 1a so as to contact or separate from the optical curved surface 1a.

A motor 16 is mounted on the upper end of the stand 13 via a mounting 16b. The drive shaft of the motor 16 has a ball screw 16 screwed to the slide plate 15.
is connected so as to extend in the Z-axis direction, and the vertical movement of the slide plate 15 is performed by the rotation of a ball screw 16 a driven by a motor 16.

A static pressure slide 18 is mounted on the slide plate 15 via a bottom plate 17. Static pressure slide 1
8 is provided with a slider 18a that can move in the same Z-axis direction as the slide plate 15, and a polishing head 20 having a polisher 21 at the front end via a holding table 19 is optically mounted on the front surface of the slider 18a. It is fixed so as to face the spherical center O of the curved surface 1a. The static pressure slide 18 is operated by a static pressure control device (not shown), and at the time of polishing, the polishing head 2 is controlled via a slider 18a by a constant pressure copying control device 18b which controls the processing pressure to be constant.
0 is controlled so that a constant load is always applied to the work 1. Here, the slider 18a is the polishing head 2
0 is provided to constitute a pressing means for pressing the polisher 21 in the normal direction of the optical curved surface 1a.

The polishing head 20 has a tool base 22 and a polisher shaft 23. As shown in FIG. 3, the tool base 22 has a large-diameter portion 22a in the upper half and a small-diameter tip shaft 22b in the lower half.
2 a is fixed to the holding table 19. At the center of the tool base 22, which is the rotation center axis of the polishing head 20, there is provided a hollow hole 24 penetrating through the inside of the large-diameter portion 22a and the tip shaft 22b in the Z-axis direction.

The polisher shaft 23 has a hole into which the tip shaft 22b of the tool base 22 can be inserted.
5 is rotatably attached to the distal end shaft 22b via bearings 26 arranged vertically. The bearing 26 is a fixing ring 27 attached to the polisher shaft 23.
Is held by A ring-shaped polisher 21 is held at the tip of the polisher shaft 23. Polisher 21
Is a columnar shape, and has a hole at the center thereof into which a tip shaft 22b of the tool base 22 can be inserted. The polisher 21 is made of an elastic material, but may be a fixed abrasive or a solid abrasive member.

A polisher 21 is provided on the outer periphery of the polisher shaft 23.
A belt 29 is wound around a drive shaft of a motor 28 as a rotating means for rotating the polisher 21. The motor 28 can rotate the polisher 21 together with the polisher shaft 23. The motor 28 is fixed to the slider 18a.

In the hollow hole 24 of the tool base 22,
A non-contact displacement meter 30 is fixed to the distal end side of the distal end shaft 22b independently of the rotation of the polisher shaft 23. The tip of the non-contact displacement meter 30 is set at a position retracted from the polished surface (tip surface) of the polisher 21, and is arranged in a non-contact state with the optical curved surface 1 a of the work 1. The non-contact displacement meter 30 is of a static capacity type, and the work 1
Can be measured with respect to the optical curved surface 1a. The signal detected from the non-contact displacement meter 30 is a code 3
1 and detected by the amplifier 32, and the data
It is taken into the PU33.

Next, the operation of the polishing apparatus having the above configuration will be described. When the polishing head 20 performs polishing, the work 1
The trajectory for scanning the optical curved surface 1a is based on an NC program in which the CPU 33 simultaneously controls the X-axis mechanism 2, the θ-axis mechanism 5, and the Z-axis mechanism 12 according to the processing shape of the workpiece 1. The distance between the optical curved surface 1a of the work 1 and the non-contact displacement meter 30 at the time of scanning is calculated as a target value in advance so that the optical curved surface 1a of the work 1 becomes a predetermined distance when the optical curved surface 1a is processed into a desired curvature. Keep it. Therefore, before machining the work 1, the optical curved surface 1a
The distance between the workpiece 1 and the non-contact displacement meter 30 is long, and becomes a target value when the workpiece 1 has a desired curvature. That is, when the distance between the tip of the non-contact displacement meter 30 and the polished surface of the polisher 21 reaches a target value, the optical curved surface 1a of the work 1 is processed to have a desired curvature.

First, the work 1 which is a workpiece is fixed to the work holder 10. Next, by executing a preset NC program by the CPU 33, the work holder 10 is rotated by the motor 11 via the work spindle 9 and the polisher shaft 23 is rotated by the motor 28 via the belt 29, respectively. The polished surface of the polisher 21 is brought into contact with the optically curved surface 1a of the workpiece 1 while rotating both of them. At this time, a constant pressure is applied to the polishing pressure of the polishing head 20 by the slider 18a by the operation of the constant pressure copying control device 18b. Then, in this state, the X-axis mechanism 2, the θ-axis mechanism 5, and the Z-axis mechanism 5
The shaft mechanism 12 is simultaneously controlled, and polishing is advanced by the polisher 21 so that the optical curved surface 1a of the work 1 becomes a desired optical curved surface 1a.

During the polishing, the polishing head 20
The non-contact displacement meter 30 disposed in the inside detects the distance from the optical curved surface 1a of the workpiece 1 being polished, and transfers the distance to the CPU 33 via the amplifier 32. Once polishing is completed, CP
It is calculated whether the displacement transferred to U33 is a desired displacement (target value), and the NC program is corrected by the CPU 33 so that the desired displacement is obtained, and polishing is repeatedly performed.

According to the present embodiment, the non-contact displacement meter 3 disposed inside the polishing head 20 while polishing the optical curved surface 1a of the work 1 with the polisher 21 provided on the polishing head 20.
The distance from the optical curved surface 1a of the work 1 is detected based on 0, and the optical curved surface 1a can be polished while optimizing the polishing conditions based on the data. Therefore, the number of times the shape measurement of the optical curved surface 1a of the work 1 is performed while the work 1 is in contact with the polisher 21 without removing the work 1 from the work holder 10 during the polishing process is minimized. Therefore, polishing can be efficiently performed by shortening the polishing processing time, and the processing cost can be reduced.

Second Embodiment A second embodiment of the present invention will be described with reference to FIGS. 4 and 5 show a polishing apparatus to which the present embodiment is applied. FIG. 4 is a front view, and FIG. 5 is a left side view of FIG. The same elements as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The polishing apparatus according to the present embodiment has a slider 18a provided on the static pressure slide 18 and movable in the Z-axis direction.
A polishing head 40 is provided on the front surface of the device via a holding table 39. The polishing head 40 is disposed so as to be inclined at approximately 45 ° in the Y-axis direction with respect to the rotation center axis 4 of the work 1. A motor (not shown) is provided inside the polishing head 40. At the tip of the drive shaft 41 of this motor,
A spherical polisher 42, which is in contact with the optical curved surface 1a of the work 1 and is polished, is attached. The polisher 42 is rotatable about a rotation shaft 43 by driving a motor.

In the vicinity of the polisher 42 of the polishing head 40, a pair of non-contact displacement meters 44 and 45 are arranged in the X-axis direction which is before and after the polishing head 40 in the scanning direction of the polishing head 40.
Are arranged. The pair of non-contact displacement meters 44 and 45
Is an L-shaped holder 46 fixed to the front surface of the slider 18a.
And are arranged in parallel with the polisher 42. The pair of non-contact displacement meters 44 and 45 each measure the distance to the optical curved surface 1a of the work 1 in a non-contact manner, and the signals are taken into a CPU (not shown) via two amplifiers (not shown) connected to the respective sensors. It has become.

Next, the operation of the polishing apparatus having the above configuration will be described. The operation of polishing the work 1 is the same as that of the first embodiment, and the description is omitted. At this time, a pair of non-contact displacement meters 44 and 45 detect the distance from the optical curved surface 1a before and after the optical curved surface 1a of the workpiece 1 to be polished by the polisher 42.

According to the present embodiment, the pair of non-contact displacement gauges 44 and 45 are configured such that the polisher 42
Since a is arranged before and after in the scanning direction for processing a, it is possible to detect the distance between the surface of the unprocessed portion and the surface in the completed state. Therefore, it is possible to detect in real time whether the polishing state has a desired accuracy, specifically, whether the difference between the front and rear surfaces in the scanning direction is small and coincides with each other, or whether the polishing state is within a predetermined range. it can.
This enables high-precision polishing,
As in the first embodiment, the efficiency of the polishing process can be improved, and the processing cost can be reduced.

Third Embodiment A third embodiment of the present invention will be described with reference to FIGS. 6 and 7 show a polishing apparatus to which the present embodiment is applied. FIG. 6 is a front view, and FIG. 7 is a sectional view of a main part of a polishing head. The same elements as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the polishing apparatus of this embodiment, a polishing head 20 is mounted on the front surface of a slider 18a movable in the Z-axis direction, as in the first embodiment. The polishing head 20 has the same configuration as that of the first embodiment, as shown in FIG. In the present embodiment, the hollow hole 24 provided in the center of the polishing head 20 is vertically penetrated. Above the hollow hole 24 of the polishing head 20, a laser length measuring device 48 fixed to the front surface of the slider 18a is arranged. The laser length measuring device 48 may be directly attached to the upper end of the polishing head 20 and may be disposed above the hollow hole 24.

Next, the operation of the polishing apparatus having the above configuration will be described. The operation of polishing the work 1 is the same as that of the first embodiment, and the description is omitted. At the time of polishing, a laser beam is radiated from the laser length measuring device 48 to the optical curved surface 1a of the work 1 through the hollow hole 24, and the distance to the optical curved surface 1a is detected.

According to the present embodiment, the optical curved surface 1a of the work 1 is polished by the polisher 21 and the optical curved surface 1a of the work 1 is
The optical curved surface 1a can be polished while detecting the distance to a and optimizing the polishing conditions based on the data. Therefore, the number of times the shape measurement of the optical curved surface 1a of the work 1 is performed can be minimized without removing the work 1 from the work holding tool 10 during the polishing process. Can be polished efficiently,
Processing cost can be reduced.

In the first, second, and third embodiments, the case where the optically curved surface 1a of the work 1 is polished to have a curved surface symmetrical with respect to the rotational axis has been described. A curved surface having an asymmetrical rotation axis can be polished by NC control of the X-axis mechanism unit 2, the Y-axis mechanism unit 3, the θ-axis mechanism unit 5, and the Z-axis mechanism unit 12, and the same effect as in the first embodiment can be obtained. Can be obtained.

The technical idea having the following configuration is derived from the above-described specific embodiment. (Supplementary Note) (1) In a polishing method for polishing an optical curved surface of a workpiece attached to a work holder, a non-contact displacement meter arranged on a polishing head while polishing the optical curved surface with a polisher provided in the polishing head. And measuring the distance between the optical curved surface and the non-contact displacement meter, and correcting the residence time of the polishing head based on the data to polish the optical curved surface into a desired shape.

According to the polishing method described in the appendix (1), by measuring the distance from the optically curved surface being polished by the non-contact displacement meter, the optics of the workpiece can be removed without removing the workpiece from the polishing apparatus. The curved surface can be polished to the desired shape,
Polishing efficiency can be improved.

[0050]

According to the polishing apparatus of the first aspect, the polisher provided on the polishing head is rotated by the rotating means for rotating the polisher, and the polisher is brought into contact with the optical curved surface of the workpiece by the moving means, and is pressed. When the optical curved surface is polished by applying a constant processing pressure to the polisher by the means, the distance from the optical curved surface can be detected by a non-contact displacement meter. Therefore, the optical curved surface can be polished while measuring the shape displacement of the optical curved surface at the time of processing without removing the workpiece from the work holder, and the polishing efficiency can be improved.

In the polishing apparatus according to the second aspect, in addition to the effect of the first aspect, the non-polished surface portion and the polished surface portion on the optical curved surface are provided by non-contact displacement meters respectively disposed before and after in the scanning direction of the polishing head. Can be polished while detecting the distance to both surfaces and grasping the polishing state in real time.

Further, in the polishing apparatus according to the third aspect, a hollow hole is provided in the rotating shaft of the polishing head, and a laser beam is irradiated from a laser length measuring device onto the optical curved surface through the hollow hole above the hollow hole. By measuring the distance to the curved surface, the same effect as in claim 1 can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view showing a polishing apparatus to which Embodiment 1 of the present invention is applied.

FIG. 2 is a left side view showing the polishing apparatus to which Embodiment 1 of the present invention is applied.

FIG. 3 is a fragmentary cross-sectional view showing a polishing head of the polishing apparatus to which Embodiment 1 of the present invention is applied.

FIG. 4 is a front view showing a polishing apparatus to which Embodiment 2 of the present invention is applied.

FIG. 5 is a left side view showing a polishing apparatus to which Embodiment 2 of the present invention is applied.

FIG. 6 is a front view showing a polishing apparatus to which a third embodiment of the present invention is applied.

FIG. 7 is a fragmentary cross-sectional view showing a polishing head of a polishing apparatus to which Embodiment 3 of the present invention has been applied.

FIG. 8 is a perspective view showing a conventional polishing apparatus.

FIG. 9 is a sectional view of a main part of a conventional polishing apparatus.

FIG. 10 is a sectional view showing a conventional polishing apparatus.

[Explanation of symbols]

 Reference Signs List 1 work 1a optical curved surface 2 X-axis mechanism 3 Y-axis mechanism 5 θ-axis mechanism 12 Z-axis mechanism 18 Static pressure slide 18a Slider 18b Constant-pressure copying controller 20, 40 Polishing head 21 Polisher 28 Motor 29 Belt 30, 44 , 45 Non-contact displacement meter 48 Laser length measuring instrument

Claims (3)

[Claims] 1. A polishing apparatus for polishing an optical curved surface of a workpiece attached to a workpiece holder, the polishing head having a polisher at a tip for rotating and processing the optical curved surface of the workpiece; Pressing means for disposing a head and pressing the polisher in the normal direction of the optical curved surface; rotating means for rotating the polisher; A moving means for moving so as to abut or separate from the curved surface, and a non-contact displacement meter attached to the polishing head or a pressing means provided with the polishing head and moved together with the polishing head; A polishing apparatus for measuring a shape of an optical curved surface by measuring a distance between an optical curved surface and a non-contact displacement meter while the polisher is in contact with the polishing machine. 2. The polishing apparatus according to claim 1, wherein the non-contact displacement meters are respectively arranged before and after in a scanning direction of the polishing head. 3. The polishing apparatus according to claim 1, wherein a hollow hole is provided in a rotation center axis of the polishing head, and a laser length measuring device is disposed above the hollow hole.